Abstract
The invention relates to a pipetting apparatus for pipetting laboratory samples into a pipetting container which can be connected to the pipetting apparatus, which pipetting container is in particular designed according to the invention, comprising a container side and a first connection section, by means of which the pipetting container can be connected to the pipetting apparatus, and comprising an information carrying device with at least one information section, which carries information, on this container side; the pipetting apparatus comprising an electric information reading device, by means of which information contained on the information reading device can be read when the pipetting container is connected to the pipetting apparatus, and which comprises at least one electric sensor device, which comprises at least one sensor section, opposite to which a measuring space is formed, wherein the sensor device is configured to read the information content of at least one information section when the latter is arranged in the measuring space. The invention furthermore relates to the pipetting container or adapter element, which can be used with the pipetting apparatus, and a method for the production thereof.
Claims
1. A pipetting apparatus (1; 20) for pipetting laboratory samples into a pipetting container (2; 2′; 140) which can be connected to the pipetting apparatus, which pipetting container comprises a container side (11; 11′; 34) and a first connection section (12; 12′; 32, 33), by means of which the pipetting container can be connected to the pipetting apparatus, and which pipetting container comprises, on the container side, an information carrying device with at least one information section (14; 14′; 35; 92; 141), which carries information, the pipetting apparatus having a connection device (42, 43), by means of which, in a connection position, the first connection section of the pipetting container can be connected to the pipetting apparatus, and an electric information reading device (44; 44a-i; 70a-c), by means of which the information can be read in the connection position, wherein the information reading device comprises at least one electric sensor device (46; 46a-h; 46i′, 46i″; 60a-e; 73a-b) which comprises at least one sensor section (46b′; 46a-h; 46i′, 46i″; 61a-d; 61d′, 61d″; 61e′, 61e″; 73b′, 73b″; 73c′, 73c″) having a sensor area (47; 67a; 67b), which is substantially planar, and, opposite to the at least one sensor section and adjoining the sensor area, at least one measuring space (50; 50′, 50″, 50′″), which is a clear space, in which the at least one information section of the pipetting container, in the connection position is arranged without the transmission of mechanical forces from the pipetting container to the sensor device, wherein the sensor device is configured to carry out a measurement which is influenced by the at least one information section in the at least one measuring space, by means of which this information can be established.
2. The pipetting apparatus according to claim 1, wherein the pipetting apparatus has a spacing device (38, 48), which, in the connection position, spaces the information carrying device at a predetermined distance of at least D=D_min from the sensor device, where 0.000 mm<=D_min<5.000 mm.
3. The pipetting apparatus according to claim 1, wherein the information reading device comprises a number N>1 of sensor devices, the sensor sections of which have a common sensor area adjoining the at least one measuring space, which sensor area has a substantially planar design.
4. The pipetting apparatus according to claim 1, wherein a cover device is arranged above the sensor area.
5. The pipetting apparatus according to claim 1, which comprises an electric control device, which is connected to the information reading device, which has a number N>1 of sensor devices, wherein the control device is configured to read out the information according to a readout method by means of the information reading device, which readout method provides for querying the sensor device sequentially in time.
6. The pipetting apparatus according to claim 1, wherein the at least one sensor device is configured to measure three distinguishable measured values, wherein a measured value can be uniquely assigned to a measurement state M of an information section.
7. The pipetting apparatus according to claim 1, wherein the at least one sensor device is configured to measure a capacitance, in particular the capacitance in the measuring space.
8. The pipetting apparatus according to claim 1, wherein the at least one sensor device is configured to measure an optical property of the information section, in particular an optical signal reflected by an information section.
9. A pipetting container (2; 2′; 140) which comprises a container side (11; 11′; 34) and a first connection section (12; 12′; 32, 33), by means of which the pipetting container can be connected to a pipetting apparatus, and an information carrier device arranged on the container side, which information carrier device has at least one information section (14; 14′; 35; 92; 141), wherein the pipetting container (2; 2′; 140) is configured for being connected with a pipetting apparatus (1; 20) in a connection position, the pipetting apparatus having a connection device (42, 43), by means of which, in a connection position, the first connection section of the pipetting container can be connected to the pipetting apparatus, and an electric information reading device (44; 44a-i; 70a-c), by means of which the information can be read in the connection position, wherein the information reading device comprises at least one electric sensor device (46; 46a-h; 46i′, 46i″; 60a-e; 73a-b) which comprises at least one sensor section (46b′; 46a-h; 46i′, 46i″; 61a-d; 61d′, 61d″; 61e′, 61e″; 73b′, 73b″; 73c′, 73c″) having a sensor area (47; 67a; 67b), which is substantially planar, and, opposite to the at least one sensor section and adjoining the sensor area, at least one measuring space (50; 50′, 50″, 50′″), which is a clear space, in which the at least one information section of the pipetting container, in the connection position, is arranged without the transmission of mechanical forces from the pipetting container to the sensor device, wherein the sensor device is configured to carry out a measurement which is influenced by the at least one information section in the at least one measuring space, by means of which this information can be established.
10. The pipetting container according to claim 9, wherein the at least one information section is configured for a predetermined reflection, in particular for an at least partial or substantially complete total internal reflection, of a predetermined optical signal.
11. The pipetting container according to claim 10, wherein the at least one information section is configured for a predetermined change in the capacitance of the measuring space of the pipetting apparatus, in which the information section is arranged.
12. A method for producing the pipetting container according to claim 9, the method comprising: providing a polymer; and using the polymer to produce a pipetting container according to claim 9 by a polymer casting process.
Description
(1) Further preferred embodiments of the pipetting apparatus according to the invention and the pipetting container according to the invention, and further aspects of the invention, emerge from the following description of the exemplary embodiments in conjunction with the figures. The same reference signs substantially denote the same components.
(2) FIG. 1 shows an exemplary embodiment of the pipetting apparatus according to the invention, which in this case is an electric dispenser, to which a pipetting container according to the invention, embodied as dispenser tip, is connected.
(3) FIG. 2a shows the dispenser tip from FIG. 1.
(4) FIG. 2b shows a further exemplary embodiment of a pipetting container according to the invention.
(5) FIG. 3 schematically shows the design of the pipetting apparatus according to the invention in one exemplary embodiment.
(6) FIG. 4a schematically shows the connection section from the pipetting apparatus of FIG. 3, and shows a further exemplary embodiment of a pipetting container according to the invention.
(7) FIG. 4b corresponds to FIG. 4a, wherein the pipetting container is arranged in the connection position and connected to the pipetting apparatus.
(8) FIGS. 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h and 5i respectively show a preferred embodiment of the arrangement of sensor devices in relation to an information reading device of a pipetting apparatus according to the invention.
(9) FIGS. 6a, 6b, 6c, 6d and 6e respectively show a preferred embodiment of a sensor device of an information reading device of a pipetting apparatus according to the invention.
(10) FIGS. 7a, 7b and 7c respectively show a view of a preferred embodiment of an information reading device of a pipetting apparatus according to the invention, with an annular carrier substrate and sensor devices arranged along an annulus.
(11) FIG. 8a shows an arrangement of sensor devices, in which optical sensor devices are arranged in accordance with the first preferred embodiment of the pipetting apparatus according to the invention.
(12) FIG. 8b shows an optical sensor device for measuring a characteristic light reflection, which can be used in the first preferred embodiment of the pipetting apparatus according to the invention.
(13) FIG. 9a shows different measurement states of the optical sensor device from FIG. 8b, respectively with a different preferred embodiment of an information section, not transparent to light, for a pipetting container according to the invention.
(14) FIG. 9b shows different measurement states of the optical sensor device from FIG. 8b, respectively with a different preferred embodiment of an information section, transparent to light, for a pipetting container according to the invention.
(15) FIG. 10a shows an isometric view of an information reading device, which comprises the arrangement of sensor devices as per FIG. 8a and the sensor devices as per FIG. 8b.
(16) FIG. 10b shows an isometric view of the information reading device from FIG. 10a with a protective cap arranged thereabove.
(17) FIG. 10c corresponds to FIG. 10b, wherein the protective cap is arranged in its assembly position.
(18) FIG. 10d corresponds to FIG. 10c, wherein a spacing device is additionally shown.
(19) FIG. 10e isometrically shows the information reading device from FIG. 10a, and a portion of a pipetting container according to the invention which is arranged in the connection position.
(20) FIG. 10f is a side view of FIG. 10e, with the beam path during the optical measurement of a sensor device being shown.
(21) FIG. 11a shows an arrangement of sensor devices, in which capacitive sensor devices are arranged in accordance with the second preferred embodiment of the pipetting apparatus according to the invention.
(22) FIG. 11 b shows a cross section of the design of a capacitive sensor device, which can be used for the second preferred embodiment of the pipetting apparatus according to the invention.
(23) FIGS. 12a, 12b and 12c respectively show a lateral cross section and a view of a preferred embodiment of the electrode arrangement of a capacitive sensor device, which can be used for the second preferred embodiment of the pipetting apparatus according to the invention.
(24) In the figures explained below, use is made of a Cartesian coordinate system in order to explain the relative positions of the components of the pipetting apparatus according to the invention and of the pipetting container according to the invention. The directional designation “up” corresponds to the direction of the positive z-axis.
(25) FIG. 1 shows an exemplary embodiment of the pipetting apparatus according to the invention, which in this case is an electric manual dispenser 1 for aspiring and dispensing liquid laboratory samples, to which a pipetting container according to the invention, designed as a dispenser tip 2, is connected. The dispenser 1 comprises a main body 3, which, in its upper section 4, comprises an optical display 5, by means of which the user obtains e.g. information in respect of the identified pipetting container, in respect of the sample volume of the liquid laboratory sample contained in the pipetting container and in respect of the set dispensing volume, which should be dispensed in a dispensing step, or other information. The dispenser 1 is configured to read out information contained on the information carrying device of the dispenser tip 2 by means of the information reading device. From this information, the dispenser 1 automatically determines the type of dispenser tip 2, in particular the maximum volume thereof. As a result of this information, the pipetting apparatus 1 is able, in particular, to calculate the required plunger stroke from a dispensing volume prescribed by the user. Said plunger stroke depends, in particular, on the cross section (perpendicular to the z-axis) of the cylindrical internal volume of the container of the dispenser tip 2. By means of the actuation element 6, the user can start the dispensing of the dispensing volume or the take-up of a volume. The dispensing process and the take-up process are moreover controlled automatically by the dispenser 1. A movement device (not shown) in the interior of the main body 3 moves the plunger arranged in the dispenser tip 2, as a result of which a liquid is dispensed or taken up by means of a pressure change in the interior volume of the container.
(26) In a connection position, the dispenser tip 2 is fixedly connected to the main body 3 of the pipetting apparatus. By means of a connection device (not shown here), the dispenser tip 2 can be plugged onto the connection section of the pipetting apparatus 1 by the user. The connection can be released by the user by means of the unlocking button 7 of the pipetting apparatus.
(27) FIG. 2a shows the dispenser tip 2 from FIG. 1 with a maximum volume of 50 ml. The dispenser tip 2 has a cylinder-like container 8, at the lower end of which a hollow cone-shaped tip 9 with a container opening 10 is arranged. Opposite to the container opening 10, the dispenser tip comprises the adapter element 17, which forms the end wall 11, embodied as cover section, of the pipetting container and which is detachably connected to the container 8. However, the end wall of the container can also be integrally connected to the container 8 and the adapter element can be arranged parallel to this end wall. The cover section 11 has a cylinder-like extension projection 13, at the end of which the connection section, embodied as connection flange 12, is formed integrally. Hence the connection section 12 is fixedly connected to the adapter element 17, and the adapter element 17 is fixedly connected to the container 8 of the pipetting container 2.
(28) FIG. 2b shows another exemplary embodiment of the pipetting container 2′, the dispenser tip 2′ with a maximum volume of 10 ml, in which the information carrying device is integrally connected to the container 8′ of the pipetting container 2′. The dispenser tip 2′ has a cylinder-like container 8′, at the lower end of which a hollow cone-shaped tip 9′ with a container opening 10′ is arranged. Opposite to the container opening 10′, the dispenser tip comprises the end wall 11′ (not visible) of the container, which is integrally connected to the container 8′. The connection section, embodied as connection flange 12′, is formed integrally onto this end wall 11′.
(29) On the side facing away from the container, the connection section 12 (or 12′) comprises a multiplicity of information sections 14 (or 14′) of the information carrying device of the dispenser tip. The information sections are arranged along a circular path on the connection section in such a way that they concentrically surround the plunger 15 (or 15′). FIG. 2a and FIG. 2b only show the upper end of the plunger of the dispenser tip, which is configured as an attachment section serving for the attachment with the movement device of the dispenser. The information is coded onto the information sections in such a way that it can be read out and captured around the z-axis, independently of the angular position of the rotation of the pipetting container. The information contained on the information sections of the pipetting container denotes the type of pipetting container, in particular the pipetting container-specific maximum volume thereof.
(30) FIG. 3 schematically shows the design of the manual pipetting apparatus 20 according to the invention, in an exemplary embodiment. The pipetting apparatus 20 has a main body 21, which is designed as a handle section and extends along an imagined axis with the axial direction A and on the upper end of which an actuation element 22 which can be operated manually by the user is provided. The pipetting apparatus 20 has an electric control device 23. The control device comprises a signal processing device for processing measurement signals from the sensor devices arranged in the lower region 25 of the main body, which sensor devices are connected to the control device by a signal line device 24. The control device furthermore has a data processing device for digital processing of data, which, in particular, serves as evaluation device for evaluating the measurement signals. The control device is furthermore designed to determine the information from the measurement signals which allows a unique inference to be drawn in respect of the pipetting container connected to the pipetting apparatus 20. Furthermore, the control device is designed to control precisely the process of dispensing a liquid volume and of taking up a liquid volume, depending on parameters which are entered by the user by means of the user interface 26.
(31) The second connection section of the pipetting apparatus is situated in the lower region 25 of the main body of the pipetting apparatus 20, in which section a connection device is provided to connect a pipetting container according to the invention to the pipetting apparatus 20.
(32) FIG. 4a schematically shows a connection section, which, for example, can be provided on the pipetting apparatus 20 from FIG. 3, and shows a further exemplary embodiment of a pipetting container 30 according to the invention. The pipetting container 30 comprises a container 31 with a hollow cone-shaped tip 36 with the container opening 37, through which opening a liquid laboratory sample can be suctioned into the container and re-dispensed therefrom. Connection elements 32, 33 are provided on at least two opposing sides of the container 31, by means of which connection elements the pipetting container 30 can, in a connection position, be fixedly locked to complementary connection elements 42, 43 of a pipetting apparatus. In a preferred design of the connection device between pipetting apparatus and pipetting container, the former preferably comprises a connection flange (see FIG. 2a, FIG. 2b) and preferably comprises a latching device on the pipetting apparatus, wherein the latching device can comprise sprung clamping jaws. The container 31 comprises an end side 34, to which a number of information sections are fixedly connected. This end side lies opposite the multiplicity of sensor devices of the information reading device when the pipetting container 30 is connected to the pipetting apparatus by a connection movement along the direction B and plugged onto the pipetting apparatus.
(33) The information reading device 44 comprises a carrier plate 45, on which a number of sensor devices 46 are arranged lying next to one another in a plane. A sensor device 46 comprises a substrate 46a′, on which a sensor section 46b′ is arranged. The sensor section 46b′ serves to carry out a measurement on an information section 35 when the latter is arranged in the connection position in the measuring space 50 and arranged lying perpendicularly opposite to the sensor section 46b′. The sensor devices are connected to the control device of the pipetting apparatus by means of an electric line device 46c′, preferably an I.sup.2C data bus.
(34) At least several sensor sections 46b′ are covered by a cover layer 47 and separated from the measuring space 50 by the latter. In this case the cover layer 47 is associated with the information reading device 44 and forms the common sensor area of the sensor sections 46b′ of the sensor devices. The cover layer 47 protects the mechanically sensitive sensor sections against mechanical impairment, dirt or chemical changes by aggressive liquids or vapours, which can originate from the pipetted laboratory samples. The cover layer is preferably made of a chemically inert material, or comprises the latter, wherein the material moreover substantially does not interfere with the measurement by the sensor devices. The material selection can therefore depend on the measurement principle realized by the sensor device. Delimiting walls 48 extend perpendicular to the plane in which the sensor devices are arranged. Said walls protect the measuring space 50 against impairments in the radially inward direction in relation to the axis A, for example against radiation or dirt. This renders the measurement by the sensor devices more reliable.
(35) In the interior volume sheathed thereby, the connection section 41 of the pipetting apparatus contains substantially all of the important components by means of which the pipetting container 30 can be connected to the pipetting apparatus in a predetermined connection position. The connection elements 42, 43 are part of a connection device, by means of which the pipetting container can be connected fixedly, but in a manner detachable by the user, to the pipetting apparatus. In this case, the delimiting walls 48 assume two additional important functions.
(36) On the one hand, the delimiting walls 48 serve as guide device, by means of which the pipetting container 30 is guided during the connection movement B into the connection position, by virtue of complementary guide sections 39 of the pipetting container 30 gliding along the inner side of the delimiting walls. The guide device preferably serves to guide the movement in the connection direction B—along the axis A of the pipetting apparatus in the present case. This is how the connection position is reached in a precise manner. The connection position is shown in FIG. 4b.
(37) On the other hand, as shown in FIG. 4b, the delimiting walls 48 serve as spacing device. What the spacing device achieves is that the information sections 35 of the information carrier device of the pipetting container are situated at a minimum distance D_min from the surface of the information reading device, namely the sensor area 47, in the connection position, which is also the measuring position in this case. To this end, the delimiting walls 48 serve as stop elements, against which complementary stop elements 38 on the pipetting container 30 abut, as shown in FIGS. 4a and 4b. What the spacing device achieves is that the sensor devices in the measuring position are situated at a defined distance from the information sections and, by means of the function of the guide device, are generally situated in a defined relative position in relation to the information sections. For many types of sensor devices, a distance in the region 0.000 mm<=D_min<=5.000 mm is suitable for carrying out reliable measurements and uniquely capturing the measurement states to be identified. The distance D_min should be selected in such a way that the plugging of the pipetting container onto the pipetting apparatus does not lead to a mechanical load on the sensor area 47, wherein contact with the sensor area (D_min=0.000 mm) may be permitted. The spacing device absorbs mechanical shocks and protects the sensor devices in this manner.
(38) FIGS. 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h and 5i respectively show a preferred embodiment of the arrangement of sensor devices in relation to an information reading device of a pipetting apparatus according to the invention. In contrast to the illustrations in FIGS. 4a and 4b, the sensor devices are shown directed upward in this case.
(39) FIG. 5a shows the information reading device 44a, comprising a substrate 45a with sensor devices 46a, which are arranged parallel and next to one another in a plane, and comprising the measuring space 50, which is arranged above the sensor devices and which comprises regions which in each case lie perpendicularly opposite to the planar surface of the sensor devices 46a. Here, the sensor devices 46a are arranged on the surface of the substrate 45a. Here, the measuring space 50 directly adjoins the surface of the sensor sections 46a. Such an arrangement enables sensitive and accurate measurements. Furthermore, it is easy to inspect and service the arrangement.
(40) FIG. 5b shows the information reading device 44b, comprising a substrate 45b with sensor devices 46b, which are arranged parallel and next to one another in a plane, and comprising the measuring space 50, which is arranged above the sensor devices and which comprises regions which in each case lie perpendicularly opposite to the planar surface of the sensor devices 46b. Here, the sensor devices 46b are arranged on the surface of the substrate 45b. Provision is made for a cover layer 47b, which respectively contacts the surfaces of the sensor sections and protects these. The cover layer 47b serves as common sensor area and protects the sensor sections lying therebelow. Such an arrangement can easily be cleaned, inspected and serviced.
(41) FIG. 5c shows the information reading device 44c, comprising a substrate 45c with sensor devices 46c, which are arranged parallel and next to one another in a plane, and comprising the measuring space 50, which is arranged above the sensor devices and which comprises regions which in each case lie perpendicularly opposite to the planar surface of the sensor devices 46c. Here, the sensor devices 46c are embedded into the substrate 45c. The surfaces of the sensor sections lie in the same plane in which the surface of the substrate lies as well. Such an arrangement can easily be cleaned, inspected and serviced.
(42) FIG. 5d corresponds to FIG. 5c. Provision is additionally made for a cover layer 47d, which respectively contacts the surfaces of the sensor sections and protects these. The cover layer 47d serves as common sensor area and protects the sensor sections lying therebelow. Such an arrangement can easily be cleaned, inspected and serviced.
(43) FIG. 5e shows the information reading device 44e, comprising a substrate 45e with sensor devices 46e, which are arranged parallel and next to one another in a plane, and comprising the measuring space 50, which is arranged above the sensor devices and which comprises regions which in each case lie perpendicularly opposite to the planar surface of the sensor devices 46e. Here, the sensor devices 46c are arranged sunk into the substrate 45e. The surfaces of the sensor sections lie below the plane in which the surface of the substrate lies. Sections 49e, 51e are arranged in the plane, laterally outside of the sensor sections, and sections 52e are arranged in the plane between the sensor sections. The sections 49e, 51e and 52e of the substrate, which extend substantially perpendicular to this plane, respectively form a delimiting wall of the portions of the measuring space 50 and protect these portions from the outside or from one another. Such an arrangement can easily be inspected and serviced and enables interference-free and accurate measurements.
(44) FIG. 5f corresponds to FIG. 5a, with provision being made for sections 49f and 51f, which extend substantially perpendicular to the plane of the sensor areas and are arranged laterally outside of the sensor sections and serve as delimiting walls of the measuring space 50 to the outside. Such an arrangement can easily be inspected and serviced and enables interference-free and accurate measurements.
(45) FIG. 5g corresponds to FIG. 5a, with provision being made for sections 52g, which extend substantially perpendicular to the plane of the sensor areas and are arranged between the sensor sections and serve as delimiting walls of the measuring space 50 toward the inside such that the different portions of the measuring space above different sensor devices do not interfere with one another. Such an arrangement can easily be inspected and serviced and enables interference-free and accurate measurements.
(46) FIG. 5h corresponds to FIG. 5a, with provision being made for sections 49h, 51 h and 52h, which extend substantially perpendicular to the plane of the sensor areas, serve as delimiting walls of the measuring space 50 and additionally subdivide the measuring space 50 into three individual measuring spaces 50′, 50″ and 50′″ such that the different measuring spaces above different sensor devices do not interfere with one another. Such an arrangement can easily be inspected and serviced and enables interference-free and accurate measurements.
(47) FIG. 5i shows the information reading device 44i, comprising a substrate 45i with sensor devices 46i arranged parallel to one another. A sensor device in each case comprises a first sensor section 46i′ and a second sensor section 46i″, which are arranged parallel to one another and lie opposite one another. Arranged between the first and second sensor section is a measuring space 50′, 50″ or 50′″, into which an information section can engage from above. Such an arrangement of a sensor device is suitable in particular for realizing a photoelectric-barrier principle. Here, the measuring space in each case directly adjoins the surface of the first and second sensor sections, which could respectively also be protected by a cover layer or cap. Such an arrangement enables interference-free and error-reduced measurements. Furthermore, it is easy to inspect and service the arrangement. The sensor sections can be attached to individual sensor substrates, at least in part, or can all be attached on common sensor substrates and, in particular, on sections of the substrate 45i.
(48) FIGS. 6a, 6b, 6c, 6d and 6e respectively show a preferred embodiment of a sensor device of an information reading device of a pipetting apparatus according to the invention. In contrast to the illustrations in FIGS. 4a and 4b, the sensor devices are also shown directed upward in this case.
(49) FIG. 6a shows the sensor device 60a. It is arranged on the substrate 61 of an information reading device. The sensor device comprises a sensor section 61a, which comprises a first sensor section 62a, which, in particular, is operated electrically and connected to the line 63a, and which furthermore comprises a second sensor section 64a, which, in particular, is operated electrically and connected to the line 65a. The first sensor section and the second sensor section lie next to one another and their sensor area lies in the same plane, which forms the common sensor area 67a. Situated above the sensor area 67a is the measuring space 50, which directly adjoins the sensor area. Such an arrangement is suitable for capacitive measurements, in which the change in the dielectric constant of the measuring space or of another capacitance value of the measuring space is detected. Such an arrangement is furthermore also suitable for e.g. reflection measurements. Here, the first sensor section forms a transmitter element and the second sensor section forms a receiver element. The emitted medium, e.g. an acoustic wave or an electromagnetic wave (preferably light), is reflected in a characteristic fashion on the information section arranged perpendicularly above the sensor area in the measurement position. This generates a characteristic measurement signal characteristic for the information or at least a fraction of the information.
(50) FIG. 6b shows the sensor device 60b. It is arranged on the substrate 61 of an information reading device. The sensor device comprises a sensor section 61b, which comprises a first sensor section 62b, which, in particular, is operated electrically and connected to the line 63b, and which furthermore comprises a second sensor section 64b, which, in particular, is operated electrically and connected to the line 65b. The first sensor section is arranged embedded in the second sensor section or arranged on the second sensor section. The first and the second sensor sections are preferably separated by a separation layer, which, in particular, is electrically insulating. The sensor areas of the first and second sensor section can lie in the same plane, which forms the common sensor area 67b. Situated above the sensor area 67b is the measuring space 50, which directly adjoins the sensor area. By way of example, such an arrangement is suitable for reflection measurements or capacitive measurements.
(51) FIG. 6c shows the sensor device 60c. It is arranged on the substrate 61 of an information reading device. The sensor device comprises a sensor section 61c, which comprises a first sensor section 62c, which, in particular, is operated electrically and connected to the line 63c, and which furthermore comprises a second sensor section 64c, which, in particular, is operated electrically and connected to the line 65c. The first and the second sensor section are arranged parallel and opposite to one another. They are separated by the measuring space 50, which respectively adjoins the sensor area of the first and second sensor section. A first section 61c′ of the sensor section 61c serves as carrier of the first sensor section and a second section 61c″ of the sensor section 61c serves as carrier of the second sensor section. The arrangement is suitable in particular as a photoelectric-barrier arrangement, in particular by virtue of the first sensor section serving as transmitter element and the second sensor section serving as receiver element. In the process, a measurement beam (preferably a light beam) which passes through the measuring space 50 is used, wherein the reception is interfered with in a characteristic fashion by an information section when the latter is arranged in the measuring position in the measuring space. However, the arrangement is also suitable for capacitive measurements.
(52) FIG. 6d shows the sensor device 60d. The latter is arranged on the substrate 61 of an information reading device. The sensor device is divided into two and comprises, separately from one another, a first sensor section 62d, which is carried by a first sensor substrate 61d′ which is supported by a first section 61′ of the substrate 61, and a second sensor section 64d, which is carried by a second sensor substrate 61d″ which is supported by a second section 61″ of the substrate 61. As in FIG. 6c, this arrangement can also be used as a photoelectric-barrier arrangement or for a capacitive measurement.
(53) FIG. 6e shows the sensor device 60e. It has a similar design to the sensor device 60d. Additionally, the sensor device 60e is designed for measuring with a spatial resolution, by virtue of, for example, determining the engagement depth to which an information section, which is inserted into the measuring space 50 from above, engages into the latter. To this end, an individual measuring position has been installed for each position in relation to the z-axis, along which, in this case, the connection movement B more particularly also takes place, which individual measuring position is associated with at least one sensor section in each case and which, in the present case, is more particularly associated with, in pairs, a first sensor section 62e′, 62e″, which respectively serves as receiver element, and a second sensor section 64e′, 64e″, which respectively serves as transmitter element. By way of example, if an information section non-transparent to the measurement beam engages into the measuring space up to a depth of the first measuring position M1, a logical ordered pair (1, 1) can be measured. By way of example, if an information section non-transparent to the measurement beam engages into the measuring space only up to a depth of the second measuring position M2, a logical ordered pair (0, 1) can be measured. By way of example, if an information section non-transparent to the measurement beam does not engage into the measuring space at all, a logical ordered pair (0, 0) can be measured. As a result of this, the sensor device 60e already has a measurement resolution of M=3. A further logical ordered pair (1, 0) can easily be defined by virtue of the information section having an opening or recess at the position M2, through which the measurement beam M2 can pass through unhindered. The measurement resolution of the sensor device 60e then lies at M=4. In general, a number M_L of measuring positions can be provided in order to achieve a spatial resolution or a measurement resolution of up to 2^M_L (i.e. two to the power M_L). The higher the measurement resolution is in the z-direction, the fewer sensor devices have to be provided next to one another, i.e. in the lateral direction (e.g. within the x-y plane).
(54) FIGS. 7a, 7b and 7c respectively show a view of a preferred embodiment of an information reading device of a pipetting apparatus according to the invention, with an annular carrier substrate and sensor devices arranged along an annulus. The concentric arrangement of a multiplicity of sensor devices or sensor sections at a constant distance enables the user to plug the pipetting container onto the pipetting apparatus at any rotational angle position around the direction of the connection movement B; this applies in particular in combination with a guide device and, in particular, in the case of a suitable selection of encoding the information on the information carrier device. The use of the pipetting apparatus becomes more convenient thereby.
(55) In FIGS. 7a, 7b and 8a, respectively 7 positions are arranged on the circular circumference of the information reading device. There are, for example, two logical measurement states per position: “sensor receives” “yes” or “no”. Since the rotational position of the pipetting container is arbitrary during insertion, the number of encoding options is restricted. Encoding options in which all contacts are actuated or not actuated also have to be dispensed with since there is no reference level using this. Hence, this results in a total of 11 encoding options when using the 7 sensor devices, i.e. 11 different types of pipetting container can be identified.
(56) FIG. 7a shows the information reading device 70a. It has an annular substrate 71a, in which a circular hole 74a is provided, which, in the case of a pipetting apparatus embodied as a dispenser, can serve for retreating the plunger of a pipetting container when the latter is arranged on the pipetting apparatus in the connection position. From the outer edge of the substrate 71a, a lateral delimiting wall 72a can extend upward and shield the measuring space above the sensor devices 73a. Adjacent sensor devices are arranged, respectively at the same constant distance, along an imagined circular path around the centre of the substrate 71. The sensor devices 73a respectively have a sensor area which lies parallel to the x-y plane and perpendicular to the z-axis or to the direction B of the connection movement.
(57) FIG. 7b shows the information reading device 70b, which is similar to that in FIG. 7a, wherein, in particular, the substrates 71a, 71b including the respective circular holes 74a, 74b are similar parts, and the lateral delimiting walls 72a, 72b are similar parts. However, the sensor devices 73b differ from the sensor devices 73a. The sensor devices 73b respectively have a sensor area which lies perpendicular to the x-y plane and parallel to the z-axis or to the direction B of the connection movement. A sensor device 73b has a similar design to the sensor device 60c, 60d or 60e, (see FIG. 6c, 6d or 6e) and has, in pairs, opposing sensor sections 73b′ and 73b″. In particular, it can have a vertical spatial resolution M1, M2 (or M_L) and/or a horizontal spatial resolution M1, M2 (or M_L′) such that this can result in an overall measurement resolution of (M_L*M_L′). Here, it is possible, in particular, to use a lower number of transmitter elements than receiver elements.
(58) FIG. 7c shows the information reading device 70c, which is similar to the one in FIG. 7a, wherein in particular, the substrates 71a, 71c including the respective circular hole 74a, 74c are similar parts and the lateral delimiting walls 72a, 72c are similar parts. The even number of first sensor sections 73c″, which are embodied as transmitter elements, and the even number of sensor sections 73c′, which are embodied as receiver elements, respectively have a sensor area which lies perpendicular to the x-y plane and parallel to the z-axis or to the direction B of the connection movement. The measuring radiation (preferably light) from a transmitter element is in each case aligned in such a way that it can impinge on each of the two adjacent receiver elements. Transmitter elements and receiver elements are arranged respectively alternately next to one another in the circumferential direction of the circle; a measuring space 50′, 50″, in which an information section can engage in the measuring position, is respectively situated be-tween a transmitter element and a receiver element. Adjacent pairs of transmitter element 76c (first sensor section) and receiver element 73c′ (second sensor section), as well as transmitter element 75c (first sensor section) and receiver element 73c′ (second sensor section), respectively, form one sensor device. The sensor devices respectively adjacent on the circumference can, for example, be operated successively in time in order to use a common receiver element 73c′ in each case. Alternatively, measurements can, at least in part, be taken simultaneously and the transmitter elements can use measurement radiation modulated e.g. by different modulation frequencies, which, after interaction with an information section, are evaluated per lock-in method by an evaluation device, depending on the modulation frequency, in order to obtain information characteristic to an information section. Provision can also be made for spatial resolution (M1, M2) or (M3, M4). These provisions can reduce the number of sensor sections 73c′, 73c″ required for a desired measurement resolution.
(59) FIG. 8a shows an arrangement of sensor devices, in which optical sensor devices are arranged in accordance with the first preferred embodiment of the pipetting apparatus according to the invention.
(60) In accordance with FIG. 8b, it is proposed that, as a sensor device 80, the sensor element has a light source 81, which emits in the direction of the information carrier device 90. Different geometries, which reflect the light with a different degree of reflection, are arranged on the pipetting container at the light impingement areas of the information section. Light-detecting receiver elements 82, onto which the light is reflected back to a different extent, are arranged, directly or indirectly next to the transmitter element 81, on the sensor device. The received light is converted into an electric current and associated with the respective measurement positions by evaluation electronics.
(61) The individual light sources are actuated, clocked successively in time, and the detectors are queried. As a result of the temporal assignment, the degree of reflection of the individual positions can be queried in succession and be associated with specific decision levels. Since the cycle times are only a few ms, the coding can be queried in a fraction of a second in a microprocessor-controlled fashion.
(62) In a preferred embodiment, it is proposed to use vertically emitting lasers, so-called VCSELs, as light sources. During the production of vertically emitting lasers, semiconductor coating processes similar to those of LEDs are employed, in which the laser resonator is constructed in a cost-effective manner on a wafer by several coating processes above one another and structured by mask processes in such a way that the laser light is emitted vertically with respect to the plane of the substrate. As a result of the laser-specific properties, the coherent light—preferably with a wavelength of 850 nm—is emitted with a small emission angle of approximately an aperture angle of 10 to 15° with respect to the normal, and so no additional focusing optical system is required. Vertically emitting lasers (VCSELs) furthermore have a low threshold and a high quantum yield, and so evaluable beam powers are already emitted at low currents of a few pA. As a result, the battery operation of the mobile pipetting apparatus becomes possible. Alternatively, it is also possible to use LEDs as a radiation source.
(63) PIN photodiodes lend themselves as receiver element or light detector. In order to capture the greatest possible proportion of the reflected light, it is proposed to arrange the photodiodes as closely as possible next to the VCSEL chip directly on the same carrier. In another exemplary embodiment, it is also feasible to assemble and contact the VCSEL directly on a photodiode (analogously to the arrangement in FIG. 6b). The use of components in which transmitter and receiver (VCSEL and photodiode) are integrated on a chip (analogously to the arrangement in FIGS. 6a, 6b, 6c) is also feasible.
(64) The encoding geometries on the edge of the pipette are preferably designed in such a way that they pass or reflect light with different degrees of reflection or different degrees of transmission. It is important for the evaluation that the light levels received by the detector can be associated with defined classes. Resulting from the posed object that one of the positions of the pipettes should be characterized as a reference position, the preferred embodiment of being able to detect 3 clearly differentiable levels (measurement resolution M=3) is furthermore proposed. Since the pipettes can be manufactured from different materials, which have different optical transparency to the laser light, different geometries are proposed, which, in particular, can be used for different materials.
(65) FIGS. 8a and 8b show the functional principle of such an information reading device with such sensor devices:
(66) A printed circuit board 83, which is designed as circular blank, serves as base plate. On this printed circuit board, the transmitter components as transmitter chip 81 are positioned in cavities 84 at 7 positions (P_a . . . P_g) on a circle with uniformly divided angular sectors. Respectively one receiver chip 82 is positioned directly next to the transmitter chip. The chips are respectively contacted by bonding wires 85a and 85b, which connect the electric contacts on the chip to conductor tracks 86 on the printed circuit board. The cavities are encapsulated using an optically transparent material 87 (preferably a polymer) and thus, as a cast cover layer, protect the components. The printed circuit board comprises all further components required for the electrical function (not illustrated in the schematic diagram).
(67) The pipetting container is placed onto the information reading device at a minimum distance D_min; component 90 represents a section of the edge (also referred to as lower edge), serving as information carrier device, of an end face of the pipetting container. An encoding step 92, which is realized by a specific encoding geometry (or a number M of distinguishable encoding geometries) and serves as information section, is situated in the edge of the end face of the pipetting container.
(68) The VCSEL 81 emits a light beam with a specific aperture angle. The light impinges on the surface of the pipette in the encoding step and is reflected. Here, at least some of the light reaches the receiver chip and is converted into an electric pulse (photoelectric current) therein. The reflected component is distinguished by virtue of e.g. how this encoding geometry is designed, in particular what angle it has, in particular according to the type of material and in particular according to the surface roughness.
(69) In respect of the preferred embodiment with optical sensor devices, which, in particular, are designed for reflection measurement, a further aspect of the invention consists of finding suitable encoding geometries, in which the effectiveness of the optical coupling between the transmitter element, more particularly the laser, and the receiver element, more particularly the photodiode, generates levels which are as defined as possible. It is preferable for 3 measurement states, which can be clearly distinguished from one another, to be enabled, namely represented by minimum/maximum coupling and a level situated therebetween (medium). A further preferred aspect consists of not introducing any additional manufacturing processes. The pipetting containers should be produced with the same manufacturing methods as have been practised up until now. Further outlay as a result of applying, adhering or printing the information carrying device onto the pipetting container should preferably be avoided. However, such steps are possible and are preferably also provided for in an alternative.
(70) FIGS. 9a and 9b show classifications of the encoding geometries according to the invention:
(71) The pipettes and the adapters introduced into the shaft are made from different materials; these are materials transparent to light (FIG. 9b) and materials non-transparent to light (FIG. 9a). Geometries are proposed for all of these materials, in which respectively a maximum optical coupling, a minimum optical coupling and preferably coupling effectiveness situated therebetween can be realized.
(72) Partial FIGS. 1A to 4B respectively show a section of the sensor with laser and photoreceiver chip positioned next to one another on the main printed circuit board, encapsulated by an optically transparent material. The edge of a pipette with different geometries is positioned on the upper side.
(73) What applies to non-transparent materials—variants 1A to 4A in FIG. 9a—is that the light can only be reflected at the lower edge of the pipetting container which faces the information reading device. In the geometry 1A, the light impinges on a pipette flank 20′, which is inclined at such an angle that as much of the emitted light as possible impinges on the photodiode from the VCSEL. In the variant 2A, in which as little light as possible should be coupled onto the detector, the flank is inclined in such a way that the light is preferably reflected away completely. In the variant 3A, the pipetting container has a hole such that it is likewise not possible for light to reach the receiver.
(74) In the variant 4A, the lower edge of the pipetting container has a recessed flank such that the light can only be partly reflected back onto the detector. FIGS. 9a and b in each case also specify the coupling effectiveness (in %), which was calculated by simulation and confirmed by practical trials.
(75) In the case of transparent materials, the assumption can be made that the light enters the material almost completely through the underside of the pipetting container. In the case 2A—parallel transparent wall—and 3B—hole in the pipette—only minimal light portions are reflected back in each case. In a further aspect of this preferred embodiment, a prismatic pyramid is formed on the outside as prism element in the case of transparent materials—see image 1B. If the light that entered into the pipette impinges on the inclined flank, the angle of emergence from the denser into the less dense medium (air) is greater than the angle of incidence and there is total internal reflection of most of the light. The light is once again reflected at the opposite flank and arrives back at the receiver. It was shown that up to 14 percent of the light is reflected back to the receiver in this manner.
(76) Since the laser light is not only emitted perpendicularly but partially also with other angles—the so-called aperture angle—the emission angle of some of the light is also smaller than the angle of total internal reflection. This effect is employed to generate the “medium” level (see 4B). In this case, the formed-on prism is inclined precisely in such a way that as far as possible precisely half of the light from variant 1A is reflected back. Calculations result in a flank angle of approximately 37° for the flank 22′.
(77) FIG. 10a shows an exemplary embodiment of the information reading device, FIG. 10b shows the equipped carrier printed circuit board of the information reading device, FIG. 10c shows the complete information reading device with a cover cap which is advantageous because it is protective.
(78) In a further aspect of the invention, the geometry of the main circuit board 131 is designed in such a way that it fits into a manual pipetting apparatus, more particularly into the housing of a conventional pipetting apparatus and comprises guide holes 132 to this end. Respectively 7 VCSEL (vertical cavity surface emitting laser) chips (134a to g) and, respectively at the same distance next to each one, a photodiode chip (135a to g) are situated on regular circle segments on a surrounding circle 133 with a defined central radius. The printed circuit board furthermore has conductor tracks for the electric connections and bond wires for contacting the chips (not illustrated in the drawing). These also establish the electric connection to the other components on the printed circuit board, which serve for signal processing. These are the microprocessor 136, a magnetic switch 137 and a plug-in socket 138, which establishes the electrical connection to the instrument and the power supply.
(79) FIG. 10d shows the information reading device in a closed state. A cover cap 139 is situated on the equipped sensor printed circuit board. The cap consists of a material that is transmissive for the wavelength of the lasers. It can optionally be designed in such a way that it simultaneously is non-transmissive for the wavelength of the surrounding light. The cap can also have a filter on its upper side, which is only transmissive for the transmitter wavelength.
(80) The space between cap and printed circuit board is completely encapsulated by a polymer 310 transparent to the transmitter wavelength, the refractive index of which polymer is matched, more particularly adapted or equalized, to the one of the cap. Here, it is advantageous if, in particular, the beam path between the photodiode and transmitter is completely filled so that the light cannot be additionally scattered at the transition to a less-dense material (for example a cavity).
(81) On its upper edge, the cap has contours 311 with ramp elements, which correspond to structures, more particularly at least one spacing element or stop element, formed onto the pipetting container in such a way that, when the pipette is rotated, the surface of the pipetting container is pressed away from the sensor area and distanced such that scratching of the sensor surface is prevented thereby. The ramp elements are part of the spacing device.
(82) FIGS. 10e and 10f show the information reading device with a pipetting container 140 plugged thereon. In the figures, the pipetting container is separated in the middle of the shaft and only that part is illustrated which lies on a spacing device of the information reading device. On its lower shaft, the pipetting container has a formed-on prism 141 at seven locations. The cover and the cast are not illustrated in the figures. It is possible to identify the printed circuit board and the transmitter and receiver, assembled thereon, as a chip, the VCSEL 134 and the photodiode 135. The light from the VCSEL—illustrated by the arrows—radiates through the cast polymer, the cover and reaches into the lower edge of the pipetting container. The light is reflected (total internal reflection) on the inclined wall of the formed-on prism, reaches the second prism flank, is reflected there again and returns to the photodiode, which is arranged next to the VCSEL, through the cap and the polymer.
(83) In a clocked manner, the sensor queries all 7 information sections in succession by virtue of respectively actuating the VCSELs separately. Here each VCSEL has a separate actuation line. The photodiodes can be queried at the same time and be connected in series. Since it is known what VCSEL is actuated at what time, it becomes possible to infer from which photodiode the received photoelectric current originates. The received photoelectric current can only originate from the associated, adjacent photodiode.
(84) In order to determine two signal levels of two measurement states that are to be distinguished from one another, which signal levels, for reflection purposes, originate from two different symmetries on the information sections, a dynamic threshold is calculated and introduced for the received electric currents from the photodiodes. In this exemplary embodiment, provision is made for significant and characteristic levels of the measurement signal to be identified for three measurement states and for the information to be able to be derived therefrom.
(85) In specific applications, it may be necessary to eliminate interfering surrounding light when evaluating the levels. To this end, it is proposed to modulate the VCSELs during operation with a specific frequency. The receivers—photodiodes—then respectively receive the DC light on which the frequency has been superposed. The received light is amplified and demodulated. The receiver can then eliminate the DC light component and evaluate the intensity of the modulated signal.
(86) The advantages of the optical sensor in accordance with the first embodiment lie in that there is no wear of the sensor device. There are no mechanically moving parts in the information reading device which could fail. The service life of the optical components is sufficiently high. The sensor only still has a planar area, which can easily be cleaned. The solution can be extended in such a way that a third measurement state or further measurement states are introduced. Hence this increases the number of encoding options. The solution in accordance with the first preferred embodiment only has low spatial requirements since the optical components only have relatively small dimensions.
(87) FIG. 11a shows an arrangement of sensor devices, in which capacitive sensor devices are arranged in accordance with the second preferred embodiment of the pipetting apparatus according to the invention.
(88) FIG. 11b shows a cross section of the design of a capacitive sensor device, which can be used for the second preferred embodiment of the pipetting apparatus according to the invention.
(89) The use of one or more capacitive sensor devices 201 enables a reliable detection of the various information sections while having improved durability compared to a mechanical solution.
(90) Capacitive sensor devices are contactless switches. In particular, the capacitive sensor devices are based on the principle of the capacitive proximity switches. The primary sensors serving as sensor devices in this case are capacitors integrated into the substrate of the information reading device. The capacitance value of such a primary sensor changes if objects approach its surface, e.g. the information section 203 with the possible cavity 204, the dielectric constant £ r of which is greater than that of air (∈r˜1). This change is evaluated by electronics, which in this case are integrated directly on the printed circuit board of the information reading device. The primary sensors are preferably, where possible, blind in the outer region of the sensor ring 201 (where the attachment grooves are) so that guide ribs next to a recess are not erroneously detected and, as a result, the recess is not identified as such. The primary sensors likewise have to have little sensitivity towards the inside, in particular so as not to detect the passing plunger of a dispenser tip. This therefore results in the sensitivity region for the primary sensors denoted by 202 in FIG. 11b.
(91) For the preferred design of the primary sensors, it is proposed to find a compromise between two preferred but partially contradictory aspects. On the one hand, it is preferred for the sensors to be as small as possible in order to avoid erroneous detections: laterally due to guide ribs or axially as a result of a badly centred cylinder shaft, possibly with flatter, wave-shaped recesses. On the other hand, the area of the primary sensor should be as large as possible in order to enable a large change in the capacitance value and hence a good signal-to-noise ratio, even if the information carrier devices are not arranged everywhere with the same distance D (preferably D=D_min) over the ring 201. Three layout variants are under discussion for the primary sensors. These are illustrated in FIGS. 12a-12c.
(92) FIGS. 12a, 12b and 12c respectively show a lateral cross section and a view of a preferred embodiment of the electrode arrangement of a capacitive sensor device, which can be used for the second preferred embodiment of the pipetting apparatus according to the invention.
(93) In laboratory trials, a capacitance value of approximately 1 pF was measured in the case of a planar, annular capacitance in accordance with the type from FIG. 12b. In the case of a finger layout as per the type in FIG. 12a, a capacitance of approximately 5 pF was measured. An information carrier device placed over the sensor area in both cases changed the value by approximately 100 fF. The variant of the electrode arrangement in FIG. 12a is particularly preferred. It was found to be the most suitable variant in respect of the measurement sensitivity. The field lines are relatively sharply delimited by the finger structure. The lateral extent of the field and its spatial depth are correspondingly low. However, as a result of the finger arrangement, a large active surface is also obtained, which promises the best possible detection.
