Abstract
A weighing device is disclosed which includes a chassis, a load cell, and a weighing pan functionally coupled to the load cell. The weighing device includes a locking device adapted and configured to selectively fix the weighing pan relative to the chassis of the weighing device. The locking device may be used to fix the weighing pan relative to the chassis of the weighing device prior to placing objects onto the weighing pan and prior to removing objects from the weighing pan, so as to inhibit inducing swings of the weighing pan, impulses and shocks on the load cell, and other detrimental effects by loading and unloading the weighing pan. A system comprising the weighing device and a method for weight determination are further disclosed.
Claims
1. A weighing device comprising: a chassis; a load cell; a weighing pan functionally coupled to the load cell; and a locking device adapted and configured to selectively fix the weighing pan relative to the chassis of the weighing device.
2. The weighing device of claim 1, wherein: the weighing pan is a hanging weighing pan which is suspended by a suspension structure at a position above a top face of the weighing pan.
3. The weighing device of claim 1, wherein: the locking device is a locking mechanism and comprises an actuation device configured to actuate at least one element of the locking mechanism.
4. The weighing device of claim 3, wherein: the at least one element of the locking mechanism comprises at least one pivotable lever connected to and pivotable by the actuation device.
5. The weighing device of claim 1, wherein: the locking device is configured to selectively lift and at least partially support the weighing pan and decouple the weighing pan from the load cell.
6. The weighing device of claim 5: wherein the weighing pan is a hanging weighing pan which is suspended by a suspension structure at a position above a top face of the weighing pan; and the weighing device further comprises a suspension arrangement to which the suspension structure links and which is configured to functionally couple the weighing pan to the load cell, wherein the locking device comprises a lifting gear which is arranged and configured to selectively lift and support the suspension structure, thereby decoupling the weighing pan from the load cell.
7. The weighing device of claim 1, wherein: the locking device is adapted and configured to lock the weighing pan by at least one of positive locking and clamping; the locking device is adapted and configured to effect a positive lock or clamping with at least one of the weighing pan and/or the suspension structure.
8. The weighing device of claim 7 wherein: the locking device is adapted and configured to lock the weighing pan by positive locking; at least one element of the locking mechanism which is actuatable by the actuation device comprises a form lock feature for effecting the positive locking for fixing the weighing pan and/or the suspension structure relative to the chassis.
9. The weighing device of claim 8, wherein: the form lock feature is shaped so as to fix the weighing pan and/or the suspension structure in a well-defined, unique position when positive locking is effected.
10. The weighing device of claim 1, wherein: the weighing device further comprises at least one weight preparation table; the at least one weight preparation table and the weighing pan are displaceable relative to each other along at least two linear axes; a first one of the at least two linear axes is a horizontal axis and a second one of the at least two linear axes is a vertical axis; displaceability is restricted to purely linear translational displacement along the at least two linear axes; the displacement along the first one of the at least two linear axes is a horizontal displacement and the displacement along the second one of the at least two linear axes is a vertical displacement; the horizontal displacement is such that the at least one weight preparation table is positionable in at least two different positions relative to the weighing pan; in a first one of the at least two different positions the at least one weight preparation table is laterally offset from a center of the weighing pan in a vertical view; in a second one of the at least two different positions the at least one weight preparation table is overlapping the center of the weighing pan in the vertical view; and the vertical displacement is such that a top face of the at least one weight preparation table is positionable at a vertical position which is above a top face of the weighing pan as well as the top face of the at least one weight preparation table is positionable at a vertical position which is below the top face of the weighing pan.
11. The weighing device of claim 10, wherein: the weighing pan and the at least one weight preparation table are enclosed within a weighing chamber of the weighing device; the weighing device is configured to restrict the any motion of the at least one weight preparation table and of the weighing pan that contributes to the relative displacement between the at least one weight preparation table and the weighing pan to within the weighing chamber.
12. A system comprising: the weighing device of claim 1; a robotic device; and at least one of a storage area and a preparation area; wherein the robotic device is adapted and configured to move an object from the storage area, if present, or the preparation area, if present, onto the weighing pan and remove an object from the weighing pan and place it in the storage area or on the preparation area; the weighing pan is placed inside a weighing chamber of the weighing device and the robotic device, the storage area, if present, and the preparation area, if present, are placed outside the weighing chamber.
13. A system comprising: the weighing device of claim 10; a robotic device; and at least one of a storage area and a preparation area; wherein the robotic device is adapted and configured to move an object from the storage area, if present, or the preparation area, if present, onto the at least one weight preparation table and remove an object from the at least one weight preparation table and place it in the storage area or on the preparation area; wherein the weighing pan and the at least one weight preparation table are placed inside a weighing chamber of the weighing device and the robotic device, the storage area, if present, and the preparation area, if present, are placed outside the weighing chamber of the weighing device.
14. A method for weight determination, comprising: placing at least one object onto a weighing pan which is functionally coupled to a load cell; taking a reading from the load cell; removing the object from the weighing pan; fixing the weighing pan relative to a chassis of the weighing device by a locking device prior to placing the at least one object onto the weighing pan; releasing the weighing pan after the at least one object has been placed onto the weighing pan and prior to taking the reading from the load cell; and further fixing the weighing pan relative to the chassis of the weighing device by the locking device after the reading from the load cell has been taken and prior to removing the at least object from the weighing pan.
15. The method of claim 14, wherein: fixing the weighing pan relative to a chassis of the weighing device comprises lifting the weighing pan and functionally decoupling the weighing pan from the load cell; and further releasing the weighing pan after the at least one object has been placed onto the weighing pan comprises lowering the weighing pan and re-establishing the functional coupling of the weighing pan to the load cell.
Description
BRIEF DESCRIPTION OF DRAWINGS
[0053] The subject matter of the present disclosure is now to be explained in more detail by means of selected exemplary embodiments shown in the accompanying drawings. The figures show:
[0054] FIG. 1 a first exemplary embodiment of a weighing device as herein suggested;
[0055] FIG. 2 a detailed view of the locking mechanism of the weighing device of FIG. 1;
[0056] FIG. 3 a first exemplary embodiment of a weighing device as herein suggested, further comprising weight preparation tables and a weighing chamber;
[0057] FIG. 4 a detail of the weighing device of FIG. 3, illustrating details of the weighing pan and a weight preparation table;
[0058] FIG. 5 a detail of a weighing device comprising a further embodiment of a locking device which comprises a lifting gear configured for lifting the weighing pan and decoupling the weighing pan from the load cell; and
[0059] FIG. 6 a diagram outlining an exemplary embodiment of the herein suggested method.
[0060] It is understood that the drawings are highly schematic, and details not required for instruction purposes may have been omitted for the ease of understanding and depiction. It is further understood that the drawings show only selected, illustrative embodiments, and embodiments not shown may still be well within the scope of the herein disclosed and/or claimed subject matter.
DESCRIPTION OF EMBODIMENTS
[0061] A first, non-limiting embodiment of the weighing device of the herein disclosed is shown in FIG. 1. Weighing device 1 comprises chassis 2, which in turn comprises housing 21 with annex 22 attached thereto. Weighing device 1 further comprises weighing pan 14. Weighing pan 14 comprises a center 23, is suspended by a suspension cradle 15, and is, through suspension cradle 15, functionally coupled to a load cell which is essentially a transducer for transforming the physical signal depending on the weight provided on weighing pan 14 to an electrical signal. The load cell is provided inside housing 21 and is thus not shown, while being familiar to a person having skill in the art. Suspension cradle 15, with weighing pan 14 attached thereto, is supported by frame 18. Frame 18, in turn, is supported on a L-shaped beam extending inside annex 22 and into housing 21, where it couples to the load cell. The L-shaped beam, as being provided inside annex 22, is not shown and is not of primary relevance to the herein disclosed subject matter. Frame 18 and said L-shaped beam jointly form a load-transmitting structure which transmits load, or gravitational forces, from a suspension arrangement 19 to the load cell. Housing 21 may further accommodate a power supply, control electronics and evaluation electronics. Annex 22 accommodates calibration weights and/or dial weights, which might be operated by rotary switches 221. Frame 18 comprises, in the exemplary embodiment, a bearing body which is shaped as a waisted body of revolution, which essentially resembles two cones meeting at their thinner ends. Suspension cradle 15, at its upper side, also comprises a waisted body of revolution bearing on the bearing body of frame 18, wherein the axes of the two waisted bodies of revolution lie transverse to each other and the waists of the bearing bodies are received withing each other. Jointly, the two waisted bodies form suspension arrangement 19, as is outlined in more detail in connection with FIG. 5. Suspension arrangement 19 provides a mobile support of the weighing pan by the frame such that weighing pan 14 is free to move around the point of attachment or pivot point and relative to the chassis within relatively wide set limits, which is important for the measurement accuracy. Annex 22 further accommodates a locking device which is provided as a mechanical locking mechanism 3. Locking mechanism 3 is adapted and configured to selectively fix and lock weighing pan 14 relative to annex 22 and thus to chassis 2. As noted above, the term locking mechanism shall be applied when locking device 3 is provided as a mechanical mechanism. More in detail, locking device, i.e., locking mechanism, 3 is adapted and configured to selectively engage with pins 39 and release pins 39 provided on the bottom of weighing pan 14, wherein only one of pins 39 is visible in the present depiction. As will be appreciated, when pins 39 are engaged by locking mechanism 3, the position of weighing pan 14 is horizontally fixed and locked relative to chassis 2 such that swinging movements of the weighing pan are inhibited. As will further be appreciated, when the position of weighing pan 14 is locked with respect to chassis 2, objects can be placed onto weighing pan 14, or can be removed from weighing pan 14, without deflecting weighing pan 14 from its resting position or otherwise inducing oscillating swings of weighing pan 14.
[0062] In embodiments, it may be provided that locking device 3 is adapted and configured to be reversibly brought into contact with a bottom face of the weighing pan and into a support relationship with the weighing pan in which it supports the weighing pan. This may include lifting weighing pan 14 if such degree of freedom is provided by the functional weighing pan support of the weighing device. In the present exemplary embodiment, for instance, the waisted body of revolution of suspension cradle 15 which in a functional weighing mode of the weighing device bears on the bearing body of frame 18 may be lifted off the bearing body of frame 18 by locking device 3 and while weighing pan 14 is supported by locking device 3, thereby disconnecting suspension arrangement 19. Consequently, weighing pan 14 is completely disconnected from frame 18, and thus eventually from the load cell. If weighing pan 14 is lowered again, the waisted bodies forming suspension arrangement 19 will self-center with each other and hence again functionally couple weighing pan 14 to the load cell.
[0063] As noted above, the skilled person will readily appreciate that a bottom and top side of weighing device 1, just like that of any weighing device of the herein disclosed type, are uniquely defined and identifiable by a skilled person by the setup of the weighing device, and thus terms referring to a vertical orientation of a weighing device, like top, bottom, above, below, higher, lower and so forth, are readily identified by virtue of the structure of the weighing device and thus have a clear and unique meaning to a person having ordinary skill in the art in the context of a weighing device.
[0064] FIG. 2 shows a plan view onto annex 22, with the weighing pan and a part of cover 222 of annex 22 removed, so as to allow a view of elements of locking mechanism 3 which are arranged inside annex 22. Locking mechanism 3 comprises an actuator device 31, which, through drive lever 32 is functionally coupled to crank arm 33. Crank arm 33 in turn is fixedly coupled to locking lever 35. Crank arm 33 and locking lever 35 are both fixedly attached to pivot axle 303, which is rotatably mounted in cover 222 of annex 22. Thus, a displacement of drive lever 32 which is induced by actuator device 31 imparts a joint pivoting action of crank arm 33 and locking lever 35 around a pivot axis defined by pivot axle 303. Actuator device 31, drive lever 32 and crank arm 33 are arranged below cover 222, or inside annex 22, respectively, while locking lever 35 is arranged on top of cover 222, or outside and on top of annex 22, respectively. Pivot axle 303 extends through cover 222 of annex 22. Second crank arm 34 and second locking lever 36 are provided mirrored to first crank arm 33 and first locking lever 35. Analogous to first crank arm 33 and first locking lever 35, second crank arm 34 and second locking lever 36 are fixedly connected to each other and rotatably mounted in cover 222 by second pivot axle 304. First crank arm 33 and second crank arm 34 are drivingly connected to each other by gearing 301. Thus, when crank arm 33 together with locking lever 35 are set in a pivoting motion by actuator device 31 through drive lever 32, second crank arm 34 together with second locking lever 36 are set in synchronous and mirrored pivoting motion, wherein the sense of rotation of the pivoting motion of first crank arm 33 together with first locking lever 35 and the sense of rotation of the pivoting motion of second crank arm 34 together with second locking lever 36 are opposite to each other. In other words, upon actuation by actuator device 31 the distal sections of locking levers 35 and 36 move in opposite direction at the same speed, or, in other words, converge towards each other or move away from each other synchronously and symmetrically. First and second locking levers 35 and 36 comprise centering locking features 37 and 38. Centering locking features 37 and 38 are generally V- or U-shaped notches or, more generally spoken, funneling concave locking features. Each of centering locking features 37 and 38 comprises an apex and two legs and thus funnel towards the apex. A freely movable counterpart element, when caught inside one of locking features 37 and 38, will be centered inside the locking feature at the apex of the respective funneling and thus centering locking feature. Hence, a counterpart element, when caught inside one of locking features 37 and 38, will be drawn into a well-defined unique position relative to the respective locking lever. A pair of pins 39 provided on the bottom of weighing pan 14, cf. FIG. 1, will thus, by further virtue of the synchronous and symmetric movement of locking levers 35 and 36, always be received in locking features 37 and 38 in a unique position and weighing pan 14 will be fixed and locked in a well-defined and unique position with respect to annex 22, and thus with respect to chassis 2. The wide mouth of each locking feature 37 and 38 allows to capture a counterpart locking element, such as pin 39 shown in FIG. 1, in a relatively large area. The locking mechanism is thus suited to capture, fix and lock the weighing pan even if the weighing pan is already in an oscillating movement. It will be appreciated that the exemplary locking device shown in FIG. 2 is not configured to be brought into a support relationship with the weighing pan. However, such embodiments are readily conceived by a person having skill in the art. For instance, means may be provided to enable a vertical movement of locking device 3, or a vertically moveable support element may be added to locking device 3.
[0065] It is understood that a weighing chamber may be provided enclosing weighing pan 14, suspension cradle 15 and frame 18, so as to protect floating weighing pan 14 from environmental interferences, like air draft, temperature changes and so forth.
[0066] FIG. 3 outlines a further exemplary, while non-nonlimiting, embodiment of the herein described weighing device. Weighing device 1 comprises weighing chamber 11 which is provided to protect mechanical measurement hardware from external interferences, like air draft, temperature changes and so forth. Generally spoken, weighing chamber 11 forms a closed volume inside which the measurement takes place. Weighing chamber 11 comprises weighing chamber door 111 which may be opened to allow access to the interior of weighing chamber 11 and transfer of objects into and out of weighing chamber 11, but shall generally be closed during measurements and, preferably, a certain time prior to measurements. As the skilled person will readily appreciate, a front wall of weighing chamber 11 has been omitted in the present depiction so as to allow a view on the interior of weighing chamber 11. Further, weighing device 1 comprises chassis 2 further comprising housing 21, which comprises, for instance, control and processing electronics. In the exemplary embodiment shown, housing 21 also houses the load cell. On the bottom of weighing device 1, weighing device 1 comprises feet 13 to support chassis 2 on a base on which weighing device 1 is placed. In any case, the structure of the weighing device clearly defines a top and a bottom of the weighing device. Thus, a vertical direction, represented by arrow z, is clearly defined with respect to the weighing device, and moreover top and bottom sides are clearly defined. Further, horizontal directions x and y may be defined, wherein horizontal is also clearly defined with respect to weighing device 1. Inside weighing chamber 11 weighing pan 14 and two weight preparation tables 16 and 17 are provided. An object or, more specifically, weight 30 is exemplarily shown on weighing pan 14. The center 23 of the weighing pan cannot be seen in FIG. 3 because weight 30 is arranged on the weighing pan 14. Weighing pan 14 is functionally coupled to the load cell which is arranged inside housing 21. Weighing pan 14, in the exemplary embodiment, is a hanging weighing pan which is suspended, for instance, at or proximate to the ceiling of weighing chamber 11, through suspension cradle 15. The balance of weighing device 1 is for instance a comparator balance which essentially compares the weight of a test object or multiple test objects, i.e., at least one test object or a set of at least one test object, to the weight of a reference weight or multiple reference weights, i.e., at least one reference weight or a set of at least one reference weight. It is understood that the at least one test object may actually comprise only one object to be weighed plus one or more offset weights of a known weight so as to shift the total weight to be measured into the measurement range of the balance. In order to increase accuracy of the measurements and assess the accuracy, it may be provided that the at least one test object and the at least one reference weight are repeatedly and alternatingly placed on weighing pan 14 and measurements taken. Each set of test weights or reference weights may be referred to as objects to be weighed. To this extent, the weight preparation tables 16 and 17 are provided inside weighing chamber 11. The test weights and reference weights, respectively, may be placed onto weight preparation tables 16 and 17 before taking the actual measurement and while weighing chamber door 111 is open. For instance, at least one test weight may be placed onto weight preparation table 16 as a first set of at least one object to be weighed, while at least one reference weight may be placed onto weight preparation table 17 as a second set of at least one object to be weighed. It is understood that as well the at least one test weight may be placed onto weight preparation table 17 while the at least one reference weight may be placed onto weight preparation table 16. That is, the objects to be weighed are prepared on weight preparation tables 16 and 17. Weight preparation tables 16 and 17 are displaceable inside weighing chamber 11 and configured to place the respective sets of at least one object provided thereon onto weighing pan 14 as well as to remove the set of at least one object from weighing pan 14 while placing them on the respective weight preparation table again. Said loading and unloading of the weighing pan may be effected in displacing the weight preparation tables in purely linear movements along horizontal axis x and vertical axis z, without applying any rotational or pivoting motion around a rotation or pivot axis. For instance, while performing a linear movement along horizontal axis x, weight preparation table 16 takes different positions relative to weighing pan 14, in which an edge 160 of weight preparation table has different distances D from an edge 140 of weight preparation table 14. Thus, after providing the sets of at least one object to be weighed on the weight preparation tables 16 and 17, weighing chamber door 111 is and remains closed and the entire measurement process, comprising repeated measurements, can take place inside the closed weighing chamber and protected from external interferences.
[0067] FIG. 4 outlines certain detail of weighing pan 14 and weight preparation table 16 of the present non-limiting embodiment. It shall be understood that any statement made with respect to weight preparation table 16 also applies to weight preparation table 17. Weighing pan 14 comprises bars 141 which are arranged on a base plate 142. Weight preparation table 16 comprises bars 161 which cantilever from a base 162 and towards weighing pan 14. Bars 141 of weighing pan 14 are parallel to each other and parallel to bars 161 of weight preparation table 16. Bars 161 of weight preparation table 16 extend parallel to each other and parallel to bars 141 of weighing pan 14. Bars 141 of weighing pan 14 and bars 161 of weight preparation table 16 extend parallel to a horizontal displacement axis of weight preparation tables 16 and 17, which, in the present embodiment, corresponds to horizontal axis x. The top edges of bars 141 of weighing pan 14 jointly form a top face of weighing pan 14. The top edges of bars 161 of weight preparation table 16 jointly form a top face of weight preparation table 16. Bars 141 of weighing pan 14 have a width A and are arranged with voids between each pair of neighbouring bars, wherein the width of the voids between neighbouring bars 141 is denoted B. The voids have a clear height H measured from the top of a bar 141 to the base plate 142 which, in the present non-nonlimiting embodiment, corresponds to height of the bars. Bars 161 of weight preparation table 16 have a width a and are arranged with voids between each pair of neighbouring bars, wherein the width of the voids between neighbouring bars 161 is denoted b. Bars 161 of weight preparation table 16 have a height h. The width B of the voids between neighbouring bars 141 of weighing pan 14 is dimensioned such that bars 161 of weight preparation table 16 can be received within the voids between neighbouring bars 141 of weighing pan 14. That is, in the presently shown exemplary embodiment, the width B of the voids between neighbouring bars 141 of weighing pan 14 is larger than the width of bars 161 of weight preparation table 16. Likewise, the width b of the voids between neighbouring bars 161 of weight preparation table 16 is dimensioned such that bars 141 of weighing pan 14 can be received in the voids between neighbouring bars 161 of weight preparation table 16. That is, in the presently shown exemplary embodiment, the width b of the voids between neighbouring bars 161 of weight preparation table 16 is larger than the width A of the bars 141 of weighing pan 14. Further, the bars 161 of weight preparation table 16 are, along the horizontal displacement axis x of weight preparation table 16, aligned or in registry with the voids between neighbouring bars 141 of weighing pan 14, and the bars 141 of weighing pan 14 are, along the horizontal displacement axis x of weight preparation table 16, aligned and in registry with the voids between neighbouring bars 161 of weight preparation table 16. Further, the height h of the bars 161 of weight preparation table 16 is smaller than the clear height H of the voids between neighbouring bars 141 of weighing pan 14. The vertical range of motion of weight preparation table 16 is provided such that the top edges of bars 161 of weight preparation table 16 may be placed above as well as below the top edges of bars 141 of weighing pan 14. That is, the top face of weight preparation table 16 may be placed vertically higher of lower than the top face of weighing pan 14, which is, due to the above-mentioned relative dimensions of the height h of bars 161 of the weight preparation table and the height H of the voids between neighbouring bars 141 of weighing pan 14, also possible when bars 161 of weight preparation table 16 are received in the voids between neighbouring bars 141 of weighing pan 14.
[0068] Referring again to FIG. 3, weighing device 1 comprises a pair of locking jaws 41 and 42 forming part of a locking device 3. Locking jaws 41 and 42 are functionally coupled to an actuator device and to each other in a manner so as to cause a synchronous and symmetric linear displacement towards and away from each other. The actuator and gearing for effecting said synchronous and symmetric movement are not visible, but possible embodiments are well-known to a skilled person. As will be appreciated, when locking jaws 41 and 42 move towards each other they will eventually capture cradle 15. As can be seen, the regions of locking jaws 41 and 42 making the contact with cradle 15 are each shaped with an apex and two legs so as to achieve a well-defined and unique locking position of weighing pan 14 with respect to chassis 2. Thus, locking device 3, including locking jaws 41 and 42, enables to fix and lock the position of weighing pan 14 prior to placing objects onto weighing pan 14 by weight preparation tables 16 and 17 and thus to avoid that a swinging motion of floating weighing pan 14 is induced by loading and unloading weighing pan 14 through weight preparation tables 16 and 17.
[0069] FIG. 5 shows a detail of a weighing device comprising a further embodiment of a locking device 3. Weighing pan 14 in this embodiment is a hanging weighing pan and is shown with object 30 placed thereon. Weighing pan 14 is suspended by suspension cradle 15. Suspension cradle 15 comprises longitudinal bars 152 and 154 extending upward from weighing pan 14. Transversely extending structures, in the present exemplary embodiment more specifically horizontal bars, 151 and 153 connect to top ends of longitudinal bars 152 and 154. Horizontal bars 151 and 153 link to suspension arrangement 19, by which weighing pan 14, via suspension cradle 15 and further via load transmitter 155, is functionally coupled to a load cell, which in turn is included in chassis 2 of the weighing device. Suspension arrangement 19 thus forms a unique point of attachment at which weighing pan 14, via suspension cradle 15 is attached to chassis 2 and to the load cell. The load cell is arranged inside housing 21 of the weighing device and is thus not shown, but is familiar to a person having skill in the art. More in detail, horizontal bars 151 and 153 of suspension cradle are fixedly connected to a first bearing body 191 of suspension arrangement 19. Horizontal bars 151 and 153 of suspension cradle 15 and first bearing body 191 may be considered to jointly form a crossbar of suspension cradle 15. The connection between horizontal bars 151 and 153 of suspension cradle 15 and first bearing body 191, the connection between horizontal bar 151 and longitudinal bar 152, the connection between horizontal bar 153 and longitudinal bar 154, and the connections between longitudinal bars 152 and 154 and weighing pan 14 are rigid connections, yielding no intentionally purposefully incorporated elasticity or movability, and thus weighing pan 14 and suspension cradle 15 jointly form a rigid functional unit. First bearing body 191 bears on second bearing body 192, which in turn is fixedly attached to and supported by load transmitter 155. Second bearing body 192 thus, via load transmitter 155, functionally connects to the load cell. Thus, when first bearing body 191 is supported on second bearing body 192, any gravitational force from first bearing body 191 is transmitted to the load cell. Bearing bodies 191 and 192 are shaped as waisted bodies of revolution, as is best seen by virtue of first bearing body 191. The shape resembles essentially that of two truncated cones joined at their lower diameter ends. First bearing body 191 and second bearing body 192 are arranged with skew axis. Thus, when first bearing body 191 is placed onto second bearing body 192, first and second bearing bodies 191 and 192 are mutually self-centering in their waists. Moreover, first and second bearing bodies 191 and 192 jointly form a pivot point for the attachment of weighing pan 14 to chassis 2. Locking device 3 is arranged proximate suspension arrangement 19, or proximate an upper end of suspension cradle 15, respectively. Locking device 3 comprises lifting gear 4. Lifting gear 4 comprises lifting actuator 44 and lifting support 45. Lifting actuator 44 is fixedly attached to chassis 2 and is configured to move lifting support 45 vertically. Lifting support 45 comprises centering pins 46 and 47, which are configured to insert into receiver holes 48 and 49. Centering pins 46 and 47 comprises truncated top cones tapering in an upward direction. The conical top end of centering pin 46 is shaped and dimensioned to fit into receiver hole 48 but not through receiver hole 48, and the conical top end of centering pin 47 is shaped and dimensioned to fit into receiver hole 49 but not through receiver hole 49. Thus, when lifting actuator 44 moves lifting support 45 upward, the top ends of centering pins 46 and 47 will eventually be received inside receiver holes 48 and 49 and center within receiver holes 48 and 49. The truncated top cones of centering pins 46 and 47 may be shaped and dimensioned such that the tips of centering pins 46 and 47 may not extent beyond the top surfaces of horizontal bars 151 and 153. Dependent on the specific design, as lifting actuator 44 moves lifting support 45 further upward, either the rims of receiver holes 48 and 49 will bear on the top cones of centering pins 46 and 47, or the bottom of horizontal bars 151 and 153 will bear on the top of lifting support 45. Upon further upward movement of lifting support 45, suspension cradle 15 with weighing pan 14 attached thereto will be supported by lifting support 45 and be lifted. Consequently, first bearing body 191 will lift off second bearing body 192. Support arrangement 19 is separated and weighing pan 14 is decoupled from the load cell. Eventually, the upper side of horizontal bars 151 and 153 will get into contact with end stop surface 441 provided on lifting actuator 44. Lifting actuator 44, via lifting support 45, exerts an upward force on horizontal bars 151 and 153 which in turn abut end stop surface 441. Horizontal bars 151 and 153 are accordingly clamped between lifting support 45 and end stop surface 441, which in turn effects a lock of the suspension cradle and the weighing pan relative to the chassis 2 of the weighing device. Once lifting actuator 44 moves lifting support 45 downward, first bearing body 191 will eventually get into contact with second bearing body 192. First and second bearing bodies 191 and 192 will, as noted above, mutually self-center in their waists, thereby re-establishing suspension arrangement 19. Lifting support 45, upon further downward movement, detaches from horizontal bars 151 and 153 and suspension cradle 15 is again supported by second bearing body 192, thereby re-establishing the functional coupling of the weighing pan to the load cell.
[0070] A method for weight determination applying the herein disclosed weighing device is illustrated in FIG. 6. The method comprises fixing the weighing pan relative to the chassis of the weighing device by a locking device at step 50 prior to placing at least one object onto the weighing pan at step 52. The weighing pan is released at step 54 after the at least one object has been placed onto the weighing pan and a weight reading is taken from a load cell to which the weighing pan is functionally coupled at step 56. Optionally, after the weight reading has been taken, the weighing pan is again fixed and locked relative to the chassis of the weighing device at step 58 prior to removing the at least one object from the weighing pan at step 60. Optionally, if such functionality is included in the locking device, the locking device may by brought into support relationship with the weighing pan prior to step 50 or between steps 50 and 52. In said case, the support relationship needs to be terminated prior to taking the weight reading at step 56, which termination may be performed between steps 52 and 54, or between steps 54 and 56, such that the weighing pan is fully released before taking readings from the load cell. The locking device may further be brought into locking relationship with the weighing pan before removing the at least one object in step 60, which may take place between steps 56 and 58 or between steps 58 and 60.
[0071] While the subject matter of the disclosure has been explained by means of exemplary embodiments, it is understood that these are in no way intended to limit the scope of the claimed invention. It will be appreciated that the claims cover embodiments not explicitly shown or disclosed herein, and embodiments deviating from those disclosed in the exemplary modes of carrying out the teaching of the present disclosure will still be covered by the claims.
REFERENCE SIGNS LIST
[0072] 1 Weighing device [0073] 2 Chassis [0074] 3 Locking device, locking mechanism [0075] 4 Lifting gear [0076] 11 Weighing chamber [0077] 13 Feet of weighing device [0078] 14 Weighing pan [0079] 15 Suspension structure, suspension cradle [0080] 16 Weight preparation table [0081] 17 Weight preparation table [0082] 18 Frame [0083] 19 Suspension arrangement [0084] 21 Housing of weighing device [0085] 22 Annex [0086] 23 Center of the weighing pan [0087] 30 Object [0088] 31 Actuator device [0089] 32 Drive lever [0090] 33 Crank arm [0091] 34 Crank arm [0092] 35 Locking lever [0093] 36 Locking lever [0094] 37 Locking feature [0095] 38 Locking feature [0096] 39 Pin [0097] 41 Locking jaw [0098] 42 Locking jaw [0099] 44 Lifting actuator [0100] 45 Lifting support [0101] 46 Centering pin [0102] 47 Centering pin [0103] 48 Receiver hole [0104] 49 Receiver hole [0105] 50 Method step [0106] 52 Method step [0107] 54 Method step [0108] 56 Method step [0109] 58 Method step [0110] 60 Method step [0111] 111 Weighing chamber door [0112] 140 Edge of weighing pan [0113] 141 Bar of weighing pan [0114] 142 Base plate of weighing pan [0115] 151 Transversely extending structure of suspension structure, horizontal bar [0116] 152 Longitudinal bar of suspension structure [0117] 153 Transversely extending structure of suspension structure, horizontal bar [0118] 154 Longitudinal bar of suspension structure [0119] 155 Load transmitter [0120] 160 Edge of weight preparation table [0121] 161 Bar of weight preparation table [0122] 162 Base of weight preparation table [0123] 191 Bearing body [0124] 192 Bearing body [0125] 221 Rotary switches [0126] 222 Cover of annex [0127] 301 Gearing [0128] 303 Pivot axle [0129] 304 Pivot axle [0130] 441 End stop surface [0131] a Width of a bar of a weight preparation table [0132] b Width of a void between neighbouring bars of a weight preparation table [0133] h Height of a bar of a weight preparation table [0134] x Horizontal direction [0135] x Horizontal direction [0136] y Horizontal direction [0137] z Vertical direction [0138] A Width of a bar of the weighing pan [0139] B Width of a void between two neighbouring bars of the weighing pan [0140] D Distance of edge of weight preparation table from edge of weighing pan [0141] H Clear height of a void between neighbouring bars of the weighing pan
