Automated dosage-dispensing system for powdery substances, and method of ascertaining that the system is ready for operation

Abstract

A system (1) dispenses dosages of a powdery substance. It has a robotic handler (2), a weighing module (8) with a weighing pan (9), at least one storage rack (4) for holding a plurality of dispensing heads (3) and at least one storage rack (6) for holding a plurality of vials (5), a dosage dispenser unit (11) with a dispensing head receiver (12), a vial handling tool (17) and a dispensing head handling tool (18), a tool-docking station (19) for the handling tools, and a controller terminal unit (20). Different weighing pan adapters (15) adapt the weighing pan to different shapes and sizes of vials. Relative to a vertical working orientation, tlower portions of the weighing pan adapters are identical, to fit the weighing pan, but upper portions are different, to accommodate different shapes and sizes of vials. A station (16) is provided for storing the weighing pan adapters.

Claims

1. A system for dispensing dosages of a powdery substance from a selected one of a plurality of dispensing heads into a selected one of a plurality of vials, the system comprising: a weighing module having a weighing pan; a plurality of weighing pan adapters that adapt the weighing pan to receive vials of different shapes and sizes, wherein the weighing pan adapters, relative to a working orientation thereof, have lower portions that are identical and are configured to fit the weighing pan, and upper portions that are different from each other by each weighing pan adapter having a unique combination of a predetermined vial-gripping height h.sub.v and an adapter-gripping width w.sub.v and are configured to accommodate different shapes and sizes of the vials, the plurality of weighing pan adapters consists of n weighing pan adapters that are assigned identifying numbers i=1 . . . n, wherein each weighing pan adapter i is distinguished from the other weighing pan adapters by at least one of the adapter-gripping height hi; and the adapter-gripping w.sub.i; a robotic handler; a storage rack for holding a plurality of the dispensing heads; a second storage rack for holding a plurality of the vials; a unit for dispensing dosages, having a rest position and a dispensing position, the unit for dispensing dosages comprising: a receiver for holding and actuating a selected one of the dispensing heads; a tool for handling a selected one of the vials, so that, when fitted with the tool for handling a predetermined vial, the robotic handler is operative to grip the vial at a predetermined vial-gripping height h.sub.y and with a vial-gripping width w.sub.v, and the robotic handler is further operative to grip each weighing pan adapter i at a predetermined adapter-gripping height h.sub.i and with an adapter-gripping w.sub.i; a tool for handling a selected one of the dispensing heads; and a station for docking the tool for handling a selected one of the vials and the tool for handling a selected one of the dispensing heads; and a controller terminal unit, configured to: control mechanical manipulations of the robotic handler in picking up and transporting selected dispensing heads and selected vials; control the movements of the unit for dispensing dosages between the respective rest and dispensing positions; and receive weight signals from the weighing module; control the unit for dispensing dosages in actuating the selected dispensing head being held by the dispensing head receiver, in response to a received weight signal; and a storage station for the plurality of the weighing pan adapters; wherein the weighing pan adapters are configured for being picked up and transported between the weighing pan adapter storage station and the weighing pan by the robotic handler with the tool for handling a selected one of the vials.

2. The system of claim 1, wherein: the weighing pan has the shape of a bottomless cylindrical cup such that, relative to the working orientation, a cylinder axis of the cup is oriented vertically; and the weighing pan has an internal wall contour comprising, from the bottom upward, a first cylindrical internal wall section with a first diameter, a second cylindrical internal wall section with a second diameter larger than the first diameter, and a conically chamfered internal border section with an upward-widening diameter, ending in a flat horizontal rim at a top thereof.

3. The system of claim 2, wherein: the lower portion of the respective weighing pan adapters is configured substantially as a hollow cylindrical tube sized and shaped for setting the weighing pan adapter into the weighing pan with the cylinder axis of the hollow tube orientated vertically.

4. The system of claim 3, wherein: the lower portion of the respective weighing pan adapters has an outside contour with a convex-rounded bottom part, a meridian curve thereof designed to position the weighing pan adapter with a desired degree of accuracy within the first cylindrical internal wall section of the weighing pan when the weighing pan adapter is lowered and set into the weighing pan; wherein, from the convex-rounded bottom part, the outside contour continues upward into a first cylindrical part having a first cylinder diameter dimensioned to ensure clearance between the first cylindrical part and the second cylindrical internal wall section of the weighing pan when the weighing pan adapter is lowered and set into the weighing pan; wherein, from the first cylindrical part, the outside contour of the identical lower portion continues upward through a tapered increase in diameter to a second cylindrical part having a second cylinder diameter dimensioned to keep a narrow clearance gap between the second cylindrical part and the second cylindrical internal wall section of the weighing pan that the weighing pan adapter will return from an accidentally tilted position to the upright position; and wherein, upward of the second cylindrical part, the outside contour of the lower portion ends in a shoulder designed to seat itself on the flat horizontal rim of the weighing pan when the weighing pan adapter is lowered and set into the weighing pan.

5. The system of claim 3, wherein the upper portion of each of the weighing pan adapters is of hollow cylindrical configuration, such that the diameter of the inside cylinder wall corresponds to the different sizes of the vials and the diameter of the outside cylinder wall may differ from the outside diameter of the lower portion of the weighing pan adapter.

6. The system of claim 5, wherein the inside cylinder wall of the upper portion of each of the weighing pan adapters is bordered at the top by a conically chamfered edge.

7. The system of claim 5, wherein each of the weighing pan adapters, inside the upper portion thereof, comprises pins which lie in a plane that extends orthogonally to the cylinder axis, protruding radially on the inside of the upper portion, the pins serving to delimit a seating depth of a vial inserted therein, such that the top of such an inserted vial protrudes sufficiently from the weighing pan adapter to allow the vial handling tool to grip the vial.

8. The system of claim 7, wherein the pins delimit the seating depths for vials of different heights, so that a top height (H) of an inserted vial, measured from the bottom of the weighing pan adapter to the top of the inserted vial is the same for all of the weighing pan adapters.

9. The system of claim 3, further comprising: a gripping area on the outside wall contour of each of the upper portions of the weighing pan adapters, configured to allow the tool for handling a selected one of the vials to grip the weighing pan adapter.

10. The system of claim 9, wherein: the gripping area is cylindrical and has a slightly smaller diameter than the rest of the outside wall of the upper portion, with beveled transitions from the gripping area to the adjacent wall portions above and below the gripping area.

11. A method for ascertaining the operational readiness of the dosage-dispensing system of claim 1, wherein consecutive numbers i=1 . . . n are assigned to the weighing pan adapters in order of decreasing gripping height h.sub.i and/or decreasing gripping width w.sub.i, characterized in that prior to starting a job lot of vials for which a specific weighing pan adapter i* is required, the unit for dispensing dosages dosage under the command of the controller terminal executes a test routine comprising a sequence of binary yes/no decisions as follows: a) check whether any vial is present on the weighing module and, if yes, remove said vial; b) in sequential order of i, determine if the weighing pan adapter that is present on the weighing pan is the weighing pan adapter with the number i and, if yes, continue at step c), else increase the number i by 1 and continue at step e); c) check whether i=i* and, if yes, end the test routine, else continue at step d); d) remove the weighing pan adapter that is currently on the weighing pan and store it in the weighing pan adapter storage station, pick weighing pan adapter i* from the weighing pan adapter storage station and set it on the weighing pan, end the test routine; and e) check whether i<n and, if yes, continue at step b), else continue at step c).

12. The method of claim 11, wherein the step a) of checking for the presence of a vial comprises the following substeps: ascertaining that the robotic handler is fitted with the tool for handling a selected one of the vials; moving the robotic handler so that the tool for handling a selected one of the vials is positioned above the weighing pan, setting the weighing module to zero, lowering the tool for handling a selected one of the vials tool to the vial-gripping height h.sub.v, closing the tool for handling a selected one of the vials to the vial-gripping width w.sub.v, raising the tool for handling a selected one of the vials tool, and receiving a weighing result from the weighing module and, if said weighing result indicates that a weight was lifted from the weighing pan, conclude that a vial was present and that the binary decision result is yes.

13. The method according to claim 12, wherein the step b) of checking for the presence of weighing pan adapter i comprises the following substeps: moving the robotic handler so that the tool for handling a selected one of the vials is positioned above the weighing pan; set the weighing module to zero; lowering the tool for handling a selected one of the vials to the gripping height h.sub.i; closing the tool for handling a selected one of the vials to the gripping width w.sub.i; raising the tool for handling a selected one of the vials; and receiving a weighing result from the weighing module and, if said weighing result indicates that a weight was lifted off the weighing pan, conclude that the weighing pan adapter i was present and that the binary decision result is yes.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The automated dosage-dispensing system according to the invention will be described hereinafter through embodiments shown schematically in the drawings, wherein:

(2) FIG. 1 represents a perspective overview of an automated dosage-dispensing system according to the invention;

(3) FIG. 2 shows portions of the weighing module and the dosage-dispenser unit and illustrates how the vial, the weighing pan adapter and the weighing pan fit inside each other;

(4) FIG. 3 illustrates the details of a weighing pan adapter according to the invention;

(5) FIG. 4 shows details of an example of a vial-handling tool; and

(6) FIG. 5 represents a flowchart of the method according to the invention applied to a dosage-dispensing system with three weighing pan adapters.

DETAILED DESCRIPTION OF THE DRAWINGS

(7) To provide an overall orientation, FIG. 1 shows a perspective overview of an automated dosage-dispensing system 1 according to the invention with a robotic handler 2 movable in mutually orthogonal directions X, Y, Z. Dosage-dispensing heads 3 are stored in a dispensing head rack 4. Receiving vessels in the form of vials 5 are stored in vial racks 6 which are seated in vial rack cradles 7. In the view of FIG. 1, the weighing module 8 is arranged to the left of the dispensing head rack 4. The weighing pan 9 is not visible in FIG. 1 inside the draft shield-enclosed weighing chamber 10, but can be seen clearly in FIG. 2. The dosage-dispenser unit 11 with the dispensing head receiver 12 is slidably supported on an understructure 13 which straddles a rear portion of the weighing module 8 (see FIG. 2). An air ionizer 14 which serves to neutralize electrostatic charges is arranged in front of the weighing chamber 10. Weighing pan adapters 15 are stored in the weighing pan adapter storage station 16. The vial-handling tool 17 and the dispensing head handling tool 18 are parked in the handling tool docking station 19. The controller terminal 20 is operatively connected to the robotic handler 2, to the weighing module 8, and to the dosage dispenser unit 11 to control their respective operating functions.

(8) The essential operating functions of the robotic handler 2 include:

(9) connecting itself to the vial-handling tool 17 or the dispensing head handling tool 18 as needed to subsequently handle a vial 5, a weighing pan adapter 15, or a dosage-dispensing head 3;

(10) picking up and transporting a weighing pan adapter 15 between the weighing pan adapter storage station 16 and the weighing pan 9;

(11) picking up and transporting a vial 5 between a vial rack 6 and a weighing pan adapter 15 that is currently seated on the weighing pan 9; and

(12) picking up and transporting a dosage-dispensing head 3 between the dispensing head rack 4 and the dispensing head receiver 12 of the dosage dispenser unit 11.

(13) The primary operating function of the weighing module 8 is to continuously weigh the vial 5 on the weighing pan 9 while powder is being dispensed into the vial 5 during a dispensing process, and to send a corresponding continuously updated weight signal to the controller terminal 20.

(14) The essential operating functions of the dosage dispenser unit 11 include:

(15) moving back and forth in the X-direction between a rest position as required to exchange dispensing heads 3, vials 5 and weighing pan adapters 15, and an operating position as required to dispense dosage material from the dispensing head 3 currently seated in the dispensing head receiver 12 into the vial 5 seated in the weighing pan adapter 15 that is currently in place on the weighing pan 9;

(16) actuating an aperture-control device of a delivery orifice (not shown in the drawings) of the dispensing head 3 currently seated in the dispensing head receiver to regulate the flow rate and shut off the flow of powder from the dispensing head 3 into the vial 5 as directed by the controller terminal 20 in response to weight signals received from the weighing module 8; and

(17) actuating any stirrer, shaker or other agitator elements of the dosage dispenser unit 11 and/or of the dispensing head 3 that serve to loosen the dosage material and promote the flow of dosage material through the delivery orifice.

(18) FIG. 2 shows details of the weighing module 8 and the dosage dispenser unit 11 and illustrates how the vial 5, the weighing pan adapter 15 and the weighing pan 9 fit inside each other. A spirit level 21 is mounted at the front of the weighing module 8. A rear portion 22 of the weighing module 8 contains the weighing cell (not shown). Connected to the weighing cell is the load receiver arm 23 which reaches by way of a pass-through opening 24 into the weighing chamber 10 (shown here with the draft shield removed) and carries the weighing pan 9. The dosage dispenser unit 11 is supported by the understructure 13 which is arranged on top of the rear portion 22 of the weighing module 8. The dosage dispenser unit 11 is slidably supported on the understructure 13 by means of slide rails 25 aligned in the X-direction which allow the dosage dispenser unit 11 (under the control of the controller terminal 20) to move backward into the rest position (shown here) and forward into the operating position. The dispensing head receiver 12 in the form of a four-pronged holder bracket is shown here without a dosage-dispensing head 3 in place. In the rest position, the sheet metal cover 26 is retracted from the weighing chamber 10, so that the air space above the weighing pan 9 is accessible for the robotic handler 2 with the vial-handling tool 17 to exchange vials 5 and weighing pan adapters 15. In the operating position, the sheet metal cover 26 is positioned over the weighing chamber 10 with the flow stream passage opening 27 centered above the vial 5.

(19) FIG. 3 illustrates an example of a weighing pan adapter 40 seated inside the weighing pan, with a vial 50 seated in the weighing pan adapter 40. The vial 50, the weighing pan adapter 40 as well as the cup-shaped weighing pan 9 are of a rotationally symmetric configuration. Seated inside each other in their operating position, their respective axes of rotational symmetry coincide in the common vertical axis A.

(20) The weighing pan 9 has the shape of a bottomless, substantially cylindrical cup or hollow tube. The inside wall of the weighing pan 9 has, from the bottom upward, a first cylindrical internal wall section 31 with a first diameter, a second cylindrical internal wall section 32 with a second diameter larger than said first diameter, and a conically chamfered internal border section 33 with an upward widening diameter ending in a flat horizontal rim 34 at the top.

(21) The lower portion of the weighing pan adapter 40 is configured in the basic shape of a hollow cylindrical tube with an outside contour designed for setting the weighing pan adapter 40 into the cup-shaped weighing pan 9. From the bottom upward, the outside contour of the weighing pan adapter has

(22) a convex-rounded bottom part 41 whose meridian curve is designed to position the weighing pan adapter 40 with a desired degree of accuracy within the first cylindrical internal wall section 31 of the weighing pan 9;

(23) a first cylindrical part 42 with a first cylinder diameter dimensioned to ensure clearance between the first cylindrical part 42 and the second cylindrical internal wall section 32 of the weighing pan;

(24) a second cylindrical part 43 with a second cylinder diameter dimensioned to keep the clearance gap between the second cylindrical part 43 and the second cylindrical internal wall section 32 of the weighing pan 9 sufficiently narrow that the weighing pan adapter 40 will return on its own from an accidentally tilted position to the upright position; and

(25) a shoulder 44 designed to seat itself on the flat horizontal rim 34 of the weighing pan 9 when the weighing pan adapter 40 is lowered and set into the weighing pan 9.

(26) The upper portions of the weighing pan adapters 40, extending upward from the shoulder 44, are of hollow cylindrical configuration with a conically chamfered inside edge 46 at the top. The diameters of the inside cylinder walls 47 of the upper portions correspond to the different sizes of the vials 50 and, consequently, the upper portions may also differ among each other in regard to their outside diameters. Three pins 48 protrude radially from the inside wall 47 towards the cylinder axis A in a star-shaped arrangement at angles of 120 from each other. The pins 48 serve to delimit a seating depth such that the top of an inserted vial 50 protrudes sufficiently from the weighing pan adapter 40 to allow the vial 50 to be gripped by the vial handling tool 17. Furthermore, in different weighing pan adapters 40 for vials 50 of different height, the respective seating depths are set so that a vial top height H from the bottom of the weighing pan 9 to the top of any inserted vial 50 is the same for all of the weighing pan adapters 40 of the dosage-dispensing system.

(27) Upward of the shoulder 44, the weighing pan adapters 40 have outside wall contours configured to allow the weighing pan adapter 40 to be gripped by the vial handling tool 17. The outside wall contour of the upper portion includes an outside wall contour section 45 configured as a gripping area with a slightly smaller cylinder diameter than the rest of the outside wall of the upper portion, with beveled transitions from the gripping area to the adjacent wall portions above and below the gripping area. This contour shape of the upper portion ensures that the weighing pan adapter cannot slip out of the grip of the vial-handling tool during transport.

(28) FIG. 4 represents a detail view of an example of a vial-handling tool 17 with four gripping fingers 171. To lift a vial 5 out of its seat in a vial rack 6 or in a weighing pan adapter 15, or to lift a weighing pan adapter 15 out of its seat in the weighing pan adapter storage station 16 or out of the weighing pan 9, the robotic handler is moved into a position where the vial handling tool is vertically above the vial 7 or weighing pan adapter 15, with the gripping fingers 171 spread wide open. Next, the robotic handler with the vial-handling tool 17 is lowered to the appropriate gripping height for the vial 7 or weighing pan adapter 15, and the gripping fingers are closed to the appropriate gripping width to firmly grasp the vial 7 or weighing pan adapter 15. Then the robotic handler can be raised back to an appropriate height to extract the vial 7 or weighing pan adapter 15 from its seat and transport it to another location as directed by the controller terminal.

(29) In the operation of the system, the robotic handler can be programmed to grip a vial 50 at a predetermined vial-gripping height h.sub.v and with a vial-gripping width w.sub.v and to grip for a weighing pan adapter 40 at a predetermined adapter-gripping height and/or adapter-gripping width. The different weighing pan adapters, identified by an index i=1 . . . n, are distinguished from each other by their different adapter-gripping heights h.sub.i and/or adapter-gripping widths w.sub.i. Consequently, if the robotic handler 2 with the vial-handling tool 17 attempts for example to grip for a weighing pan adapter i with a higher gripping height h.sub.i and/or a wider gripping width w.sub.i than the weighing pan adapter that is actually seated in the weighing pan 9, the robotic handler 2 will fail to capture the weighing pan adapter that is seated in the weighing pan and will therefore come up empty. This distinction of different adapter-gripping heights h.sub.i and/or adapter-gripping widths w.sub.i is the basis for the method that is illustrated in FIG. 5.

(30) The method illustrated by the flowchart diagram in FIG. 5 is performed prior to the start of every new job lot of vials in order to ascertain that the appropriate weighing pan adapter is in place in the weighing pan. In the general case of a system with n weighing pan adapters, consecutive numbers i=1 . . . n are assigned to the weighing pan adapters in order of decreasing gripping height h.sub.i and/or decreasing gripping width and the specific weighing pan adapter required for the new job lot of vials is identified by the index i=i*. In the specific example with three weighing pan adapters (n=3) which is shown in the flowchart, the weighing pan adapters are identified as large, medium and small. With the vial-handling tool coupled to the robotic handler 2, the actions (shown as rectangles) and decisions (shown as diamonds) of the method are:

(31) Step 101: Set the balance to zero, actuate the robotic handler with the vial-handling tool to perform the motions to grip and to lift up a vial that may be seated in the weighing pan adapter on the weighing pan.

(32) Step 102: Based on a weighing signal from the weighing module, determine whether a weight has been lifted from the balance pan and, if yes, continue at step 103, if no continue at step 104.

(33) Step 103: remove the vial from the balance pan to a predetermined vial-dump location.

(34) Step 104: Set the balance to zero, actuate the robotic handler with the vial-handling tool to perform the motions to grip and to lift up the large weighing pan adapter from the weighing pan.

(35) Step 105: Based on a weighing signal from the weighing module, determine whether a weight has been lifted from the balance pan and, if yes, continue at step 106, if no continue at step 108.

(36) Step 106: Based on the vial size specified for the upcoming job lot, determine if the large weighing pan adapter is the correct adapter for the job and, if yes, set the large weighing pan adapter back on the weighing pan and terminate the method, if no continue at step 107.

(37) Step 107: Store large weighing pan adapter at the weighing pan adapter storage station, bring required weighing pan adapter from the storage station to the weighing pan, terminate the method.

(38) Step 108: Set the balance to zero, actuate the robotic handler with the vial-handling tool to perform the motions to grip and to lift up the medium weighing pan adapter from the weighing pan.

(39) Step 109: Based on a weighing signal from the weighing module, determine whether a weight has been lifted from the balance pan and, if yes, continue at step 110, if no continue at step 112.

(40) Step 110: Based on the vial size specified for the upcoming job lot, determine if the medium weighing pan adapter is the correct adapter for the job and, if yes, set the medium weighing pan adapter back on the weighing pan and terminate the method, if no continue at step 111.

(41) Step 111: Store medium weighing pan adapter at the weighing pan adapter storage station, bring the required weighing pan adapter from the storage station to the weighing pan, terminate the method.

(42) Step 112: Based on the vial size specified for the upcoming job lot, determine if the small weighing pan adapter is the correct adapter for the job and, if yes, terminate the method, if no continue at step 113.

(43) Step 113: Store small weighing pan adapter at the weighing pan adapter storage station, bring required weighing pan adapter from the storage station to the weighing pan, terminate the method.

(44) While the invention has been described through the presentation of a specific embodiment, it is considered self-evident that numerous additional variants could be developed based on the teachings of the present invention. For example, the inventive concept could also be implemented with an articulated swivel-arm robot instead of the illustrated XYZ-system, or the vial-handling tool could be designed to approach and grasp a vial or a weighing pan adapter laterally from a side rather than from above, or the weighing pan adapters could be designed for receiving vessels other than the illustrated cylindrical vials. It should be understood that such alternative implementations of the inventive concepts fall within the bounds of protection that is hereby sought for the present invention.