DEVICE AND METHOD FOR CALIBRATION OF VELOCITY AND BREAKING FORCE OF A TABLE TESTING DEVICE

Abstract

The invention relates to a device for fitting a tablet testing device with a calibration unit. The calibration unit allows of calibrating and adjusting the velocity or breaking force of a breaking jaw of such tablet testing device, for determining the breaking hardness of tablets. The invention allows of calibrating the velocity of movement of the breaking jaw and the breaking hardness applied in timely intervals, as to comply with modern quality control standards for pharmaceutical instruments of measurement. The device is employed for temporarily fitting a tablet testing device for calibration, and is mounted onto the tablet testing device only for the purpose of conducting calibration runs, whilst storing the bulky and huge calibration device separate from the tablet testing device during times of normal operation.

Claims

1. Device for calibrating a tablet testing device which is a measuring system for velocity and breaking force of a breaking jaw in a tablet testing device, comprising at least one measuring device for measuring velocity and breaking force of a breaking jaw of said tablet testing device; a computer unit for reading and evaluating the data from measurement Characterized in that said computer unit comprises a communication interface to a tablet testing device the latter of which comprises a display unit and a data entering unit, and connections means between the one or several measuring devices, the computer unit and the communication interface, such as that the device can be connected via the communication interface with the tablet testing device, and wherein the data obtained from the measuring units can be transmitted to the tablet testing device via the communication interface, and whereby these data can be made visible on the display unit and can be processed via the data entering unit of the tablet testing device, and the computer unit can be employed for evaluating the data obtained by measuring velocity and breaking force and whereby the actuator of the breaking force of the tablet testing device can be controlled and calibrated.

2. Device according to claim 1, characterized in that at least one of said at least one measuring device is at least one of a distance measuring unit and a load cell.

3. Device according to claim 2, characterized in that the distance measuring unit is selected from the group of an optical measuring device and a laser-guided measuring device.

4. Device according to claim 2, characterized in that the distance measuring unit is a series of electric contacts which serve to measure the distance of travel of the breaking jaw.

5. Device according to claim 1, characterized in that the communication interface to a tablet testing device is USB plug-in connection.

6. Device according to claim 1, characterized in that the connection means between the one or several measuring devices, the computer unit and the communication interface are electric wires.

7. Device according to claim 1, characterized in that the computer unit is a computer that evaluates the data obtained by measuring velocity and breaking force autonomously and transmits them to the display unit and the data entering unit of the tablet testing device.

8. Device according to claim 1, characterized in that the computer unit is a junction box which transmits the data obtained from measuring velocity and breaking force to the computer of the tablet testing device.

9. Device according to claim 1, characterized in that said device allows of calibrating velocity or breaking force or both.

10. Device according to claim 1, characterized in that the device allows for at least one of recording velocity and breaking force.

11. Device according to claim 1, characterized in that that the device can be mounted onto a tablet testing device for the purpose of calibration.

12. Method of calibrating the velocity or breaking force of a breaking jaw of a tablet testing device, wherein in a tablet testing device an individual tablet to be measured is placed in a testing chamber between an opposing jaw and a breaking jaw of the tablet testing device, the breaking jaw is moved at a preset speed onto the opposing jaw of the tablet testing device, characterized in that the tablet testing device is connected to a calibration device which comprises at least a measuring unit for measuring velocity or breaking force of a breaking jaw, a computer unit, a communication interface, a connection means between the one or several measuring units, the computer unit and the communication interface, measuring the distance of travel of the breaking jaw per time unit or the breaking force and whereby the velocity or the breaking force of the breaking jaw is determined and is calibrated versus prestored values, and the tablet testing device is disconnected again from the calibration device after calibration.

13. Method according to claim 12, characterized in that the method for breaking force and velocity of the breaking jaw is measured and calibrated versus prestored values.

14. Method according to claim 12, characterized in that the calibration is conducted versus benchmarked calibration values that are stored in the computer unit.

15. Method according to claim 12, characterized in that the calibration values versus which one does calibrate are stored on an external computer and the calibration device is connected with the external computer and the with the computer of the tablet testing device, for conducting a calibration.

16. Method according to claim 12, characterized in that the velocity of the breaking jaw is adjusted at a value of from 0.1 mm/sec to 3.0 mm/sec by calibrating.

17. Method according to claim 12, characterized in that that when calibrating, a measurement for linearity deviation is done by measuring within the distance of travel of the breaking jaw up to three points in a line.

18. Method according to claim 12, characterized in that the device is mounted onto the tablet testing device during calibration.

19. Method for measuring tablets, comprising the step of using a tablet testing device calibrated by means of a device for calibrating a tablet testing device which is a measuring system for velocity and breaking force of a breaking jaw in a tablet testing device, comprising at least one measuring device for measuring velocity and breaking force of a breaking jaw of said tablet testing device; a computer unit for reading and evaluating the data from measurement Characterized in that the computer unit comprises a communication interface to a tablet testing device the latter of which comprises a display unit and a data entering unit, and connection means between the one or several measuring devices, the computer unit and the communication interface, such as that the device can be connected via the communication interface with the tablet testing device, and wherein the data obtained from the measuring units can be transmitted to the tablet testing device via the communication interface, and whereby these data can be made visible on the display unit and can be processed via the data entering unit of the tablet testing device, and the computer unit can be employed for evaluating the data obtained by measuring velocity and breaking force and whereby the actuator of the breaking force of the tablet testing device can be controlled and calibrated.

20. Method according to claim 19, characterized in that after calibrating the velocity and the breaking force of the breaking jaw, further the dimensions of the tablet are determined.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The invention is illustrated by four drawings wherein it is understood that the drawings are representing embodiments but are not limiting to the invention.

[0049] FIG. 1 shows a device according to the present invention, which allows of retrofitting current tablet testing devices.

[0050] FIG. 2 shows the testing chamber of a tablet testing device which is equipped with the device according to the present invention, from an inclined perspective from above.

[0051] FIG. 3 shows the testing chamber of a tablet testing device which is equipped with the instant device, from lateral view.

[0052] FIG. 4 shows a device according to the present invention which is fitted for being mounted onto a tablet testing device by pin connectors.

DETAILED DESCRIPTION

[0053] In FIG. 1 a mobile device (1) according to the present invention for calibration tablet testing devices is shown detached from a tablet testing device. It comprises a distance measurement unit (2), which is fitted with pin connectors (3), wherein the distance measurement unit (2) is connected via a wire as connection means (4) with a computer unit (5), further with a load cell (6) which is likewise connected via a wire as connection means (4) to the computer unit (5), and a USB plug-in part as communication interface (7) which is connected via a wire (4) to the computer unit (5), too. Via the USB plug-in part (7) the device (1) may be connected to the tablet testing device (8). Via the pin connector (3) the distance measurement unit may be mounted onto the tablet testing device (8). Here the distance measurement unit (2) is equipped with a laser-guided measuring device (2a) for measuring the distance of travel.

[0054] In FIG. 2 it is shown the testing chamber (9a) of a tablet testing device (8), which may be calibrated with the device (1) according to the present invention. The testing chamber (9a) is formed by a positioning surface (9) into which an individual tablet (10) is guided after thinning. The tablet (10) is aligned by a positioning device (not shown) in the testing chamber (9a) as to rest between breaking jaw (11) and opposing jaw (12). After that, the breaking jaw (119 is moving into direction of the arrow onto the opposing jaw (12) until the tablet (19) is jammed between the breaking (11) and the opposing jaw (12). The distance of travel passed by the breaking jaw (11) is determined with an optical device als distance measurement unit (2). By the residual distance to the opposing jaw (12) one dimension, e.g. in case of an oblong tablet (10) the width, may be determined. After jamming and measuring one or several dimensions of the tablet (10), the breaking force is increased up to the point that the tablet (10) finally breaks. The force applied therein is measured by a load cell (6). The breaking jaw (11) resides on a sledge (13) which can be moved into direction of the testing chamber (9a) by a rotating device (13a). The sledge (13) is propelled by an actuator (14). The latter resides at the backside of the sledge (13) and propels the sledge (13) via a belt-driven spindle (14a) and a belt (14b) wherein the sledge (13) is moved along with the breaking jaw (11) onto the opposing jaw (12) or away from it.

[0055] In FIG. 3 it is shown the tablet testing device (8) in a lateral perspective. It is shown first the testing chamber (9a), the breaking jaw (11) and the opposing jaw (12) wherein the breaking jaw (11) is connected via a connector (11a) with a load cell (6). The load cell (6) resides on a sledge (13) which is propelled by a motor als actuator (14) by means of a belt (14b). The sledge (13) is movable in direction of the arrow. Between the breaking jaw (11) and the opposing jaw (12) a tablet (10) is positioned. Upon moving the sledge (13) into direction of the arrow, the breaking jaw (11) is moved into direction of the opposing jaw (12). The movement is continued up to the point that the tablet (10) is jammed in between the breaking (11) and the opposing jaw (12). The breaking force is only raised to a point at which the tablet (10) does not break. Exemplarily, the dimensions of the tablet (10) are determined by the distance of travel. The passed distance is determined optically by an optical distance measurement unit (2). As an example, hee it is used a laser-guided distance measurement device (2a). From the distance of travel passed per time unit, the velocity is determined. The latter is stored and used for calculating an optimal value for the velocity. This optimal value is used then with all subsequent measurement runs on tablets as the benchmark for calibration.

[0056] In FIG. 4, a device for calibration according to the present invention (1) is mounted on a tablet testing device (8) into direction of the arrow. Shown is the device (1) of the distance measurement unit (2), the computer unit (5), the load cell (6), the connecting means (4) and the communication interfaces (7). Further shown is the tablet testing device (8), the testing chamber (9a), a tablet (10) in the testing chamber (9a), the breaking jaw (11), the opposing jaw (12), the sledge (13) and actuator unit for the sledge (14). The tablet testing device (8) is further equipped with a computer unit (15) for measurement. What is shown is a PC as an external computer (16) which has stored the reference values as calibration values.

[0057] For calibration a device (1) is mounted in direction of the arrow onto the tablet testing device. The device (1) is then connected via a communication interface (7), an USB plug-in part for instance, with the computer (15) of the tablet testing device (8) and the PC of the external computer (16). By means of that, calibration versus the stored benchmarked calibration values may be performed. After calibration, the device (1) for calibration is disconnected again from the tablet testing device (8), the computer of the tablet testing device (15) and the PC as an external computer (16).