AU705258B2

AU705258B2 - A tablet dispenser

Info

Publication number: AU705258B2
Application number: AU64341/96A
Authority: AU
Inventors: Alfonso Segura
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-09-01
Filing date: 1996-08-29
Publication date: 1999-05-20
Anticipated expiration: 2016-08-29
Also published as: AU6434196A

Description

-1- A TABLET DISPENSER Technical Field The present invention relates to dispensers to dispense predetermined numbers of tablets.

Background of the Invention Machines which dispense tablets are relatively complex and are therefore expensive and difficult to maintain. More particularly, they are directed to large commercial operations and are not well suited to applications in which smaller numbers of sets of tablets are required.

Object of the Invention It is the object of the present invention to overcome or substantially ameliorate the above disadvantages.

Summary of the Invention 0o0. There is disclosed herein a tablet dispenser to dispense a predetermined number of tablets, said dispenser comprising: 20 a base; *0 a tray to receive tablets to be dispensed, said tray being mounted for angular **00 Soo• reciprocation about a generally vertical axis and generally vertical reciprocation relative :to said base, said tray providing a generally horizontal dispensing path extending angularly about said axis, which path extends to a dispensing outlet in the tray; reciprocation means to cause said vertical and angular reciprocation; •means to detect tablets passing through said outlet; and 0 control means to control said reciprocation means so that said tray is moved to *0 dispense a predetermined number of tablets.

Brief Description of the Drawings A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings wherein: Figure 1 is a schematic parts exploded perspective view of a tablet dispenser; and Figures 2A to 2C are a block diagram, schematic circuit and timing diagram relating to the control device employed in the dispenser of Figure 1.

[N:\LIBTT]00999:mff -2- Detailed Description of the Preferred Embodiment In the accompanying drawing there is schematic depicted a dispenser 10 to dispense a predetermined number of tablets. The dispenser 10 includes a base 11 with which there is associated an outer casing consisting of casing halves 12.

The base 11 includes four pedestals 13 which support a platform 14.

Supported on the platform 14 is a tray assembly 15 including a tray base 16, a tray 17 and a cover 18. The tray 17 is mounted on the base 16 by means of flanges 19, while the base 16 is supported on the platform 14 by resilient members 20. The members each include a pair of end flanges 21 and 22, with the flanges 21 being attached to the platform 14, and the flanges 22 being attached to the base 16. There is an inclined portion 23 extending between each associated pair of end flanges 21 and 22. In this embodiment, the resilient members 20 are formed of spring steel and are bent metal strip.

Attached to the platform 14 is a motor assembly 24 including a permanent 15 magnet 25. The magnet 25 is directly supported by a generally annular support member 26 attached to the platform 14. Mounted internally of the motor assembly 24 S is a coil, which when activated by an alternating current vibrates vertically. The coil is connected via a shaft to the base 16 so that it is caused to vibrate vertically. This vertical vibration is also translated into angular vibration due to the configuration of the resilient members 20, that is the inclination of the portions 23. Accordingly, the tray 17 is caused to vertically oscillate, as well as angularly oscillate about the axis 27.

The tray 17 defines a generally annular path 28 about which the tablets move so that the tablets are delivered one at a time to an outlet opening 29 in the tray 17.

The outlet opening 29 is associated with a chute The chute 30 is mounted on the platform 14 and there is associated therewith a pair of flanges 31 and 32 which receive sensors to determine when a tablet is dispensed down the chute The operation of the motor assembly (or more simply the vibrator) 24 by a control circuit 50 will now be described with reference to Figs. 2A to 2C. In the preferred embodiment of the invention, the vibrator 24 can be operated programmably using a general purpose computer or the like, or manually using a manual input device.

As shown in Fig. 2A, the vibrator 24 is operated by a control circuit coupled thereto. The control circuit 50 consists of three functional modules: tablet detected signal processing circuit 50A, actuation circuit 50B, and control signal processing circuit 50C. The tablet detection circuit 80 is coupled to control circuit and provides a tablet detected signal 82 to the tablet detected signal processing circuit of control circuit 50. As will be described below, the tablet detection circuit preferably consists of two photo diodes oppositely positioned in the upper portion of the chute 30 in the vicinity of the outlet opening 29. The pair of photo diodes are [N:\LIBTT]0O999:MMC connected to the flanges 31 and 32, respectively and provide a pulse in the tablet detected signal 82 to the control circuit 50 when a tablet is detected passing through the outlet opening 29 and falling down the chute The control circuit 50 also receives a number of inputs to the control signal processing circuit 50C including: a programmable input signal 51, a manual input 52, and a vibration input 53.

The vibrator 24 is actuated by providing either the programmable input signal 51 from a general purpose computer or the manual input 52 to the control signal processing circuit 50C. In turn, the control signal processing circuit 50C enables the actuation circuit 50B which causes the vibrator 24 to begin vibrating and thereby angularly oscillate the tray 17. The level of vibration produced by the vibrator 24 in response to the control circuit 50 can be selected using the vibration input 53 coupled to the control signal processing circuit 50C. In this way, variable levels of vibration for the vibrator 24 can be selected so as to account for the size and/or weight of tablets to 15 be dispensed using the dispenser The vibrator 24 continues to vibrate until a tablet contained in the tray 17 o passes through the outlet opening 29 and falls down the chute 30. In this way, the tablet interrupts the light beam across the upper portion of the chute 30 between the *"*"*transmitter and the receiver (photo diodes) of the tablet detection circuit 80. The interruption of the light beam of the tablet detection circuit 80 produces a pulse in the """tablet detected signal 82, which is provided to the tablet detected signal processing circuit 50A. In response to the pulse of the tablet detected signal 82, the tablet detected signal processing circuit 58 disables the actuation circuit 50B and turns off the vibrator 24.

The dispenser 10 according to the preferred embodiment is thus able to advantageously dispense tablets while reducing the complexity and cost of the device, thereby overcoming disadvantages of the prior art. In particular, the dispenser 10 can be manually operated or programmably operated to dispense tablets. In addition, the actuation of the vibrator 24 can be controlled using a vibration input 53 provided to the control circuit 50 to account for differing sizes and/or weights of the tablets to be dispensed. In this way, smaller vibrations can be produced in the vibrator 24 for dispensing small and/or light tablets in a controlled fashion, while larger vibrations can be produced in the vibrator 24 for larger tablets.

Fig. 2B is a detailed schematic diagram of the control circuit 50 coupled to the vibrator 24, the tablet detection circuit 80, and a transformer 54 (not shown in Fig.

2A).

As shown in Fig. 2B, the control circuit 50, the tablet detection circuit 80, and the vibrator 24 are powered using a multi-step transformer 54 coupled to mains AC power supply. The transformer 54 is a step-down transformer connected to 230-240 [N:\LIBTT]00999:MMC -4volts, 50 Hz AC power on the primary side and the secondary side has four taps 54A to 54D that provide a range of voltage amplitudes. The taps 54A to 54D are selectively connected to the vibrator 24 using switch 58 to provide variable levels of vibration for dispensing tablets dependent upon the size and/or weight of the tablets to be dispensed.

The control circuit 50 is coupled to AC power from one of the taps 54A of the transformer 54 by a rectification circuit to provide supply voltage Vsupply, which is also provided to the tablet detection circuit 80. As shown, the rectification circuit consists of a diode 56 IN4001) connected to tap 54A by its anode, and the voltage Vsupply is provided at its cathode across a capacitor 57 2200pf, 16V) coupled between the cathode of diode 56 and earth. The voltage Vsupply is preferably 12 volts.

The actuation circuit 50B consists of a capacitor 67, diode 68, zener diode 69 and a relay 59 (12V, 50mA). The tablet detected signal processing circuit 50A consists of transistors 60 to 62 and capacitor 71. The control signal processing circuit consists of diode 56, capacitor 57, switch 52, and transistors 63 to is The level of vibration to be produced by vibrator 24 is selected by coupling terminal 24A of the vibrator 24 via switch 58 to one of the four taps 54A to 54D of transformer 54. When the control circuit 50 turns off the vibrator 24, the relay 59 between terminal 24B of the vibrator and earth is open circuited.

As mentioned above, the vibrator 24 can be actuated by a manual input S. 20 through the control circuit 50 or by applying an input signal 51 from a programmable control device such as a computer. In the case of manual input, switch 52 is closed connecting an input of the relay 59 to earth and thereby causing the relay 59 to connect terminal 24B of the vibrator 24 to earth. Alternatively, a programmable input signal 51 such as that shown in Fig. 2C in which the signal has a nominal level of -12 volts and a short pulse which has an amplitude of zero volts can be applied to the control signal processing circuit 50C. In particular, the DC-blocked pulse of the input signal 51 is applied to the base of transistor 65 causing it to conduct and discharging capacitor 73, which is coupled between the base of transistor 64 and earth. In turn, the transistor 64 is turned off and transistor 63 is turned on and thereby actuating relay 59 to connect terminal 24B of the vibrator 24 to earth. In this manner, the vibrator 24 is actuated to begin dispensing a tablet from the tray 17 (not shown) through the outlet opening 29 and down chute The actuation circuit 50B continues to actuate the vibrator 24 until a tablet passing into chute 30 is detected by the tablet detection circuit Light emitted by photo diode 88 is normally detected by receiving photo diode However, when a tablet passes through the outlet opening 29 into the chute the tablet interrupts the light beam by passing between transmitting and receiving photo diodes 80A and 80B of the tablet detection circuit 80 producing a pulse in the tablet detected signal 82 which is provided to the base of transistor 60. Transistors 60 and 61 [N:\LIBTT]OO999:MMC amplify the tablet detected pulse and provide it to the base of transistor 62, which has a capacitor 71 coupled between the base 71 and earth. Transistor 62 in turn actuates relay 59 causing it to become open circuited and thereby interrupting the connection between terminal 24B of the vibrator 24 and earth to turn the vibrator, or motor assembly, 24 off. Accordingly, the dispenser 10 can be operated manually or programmably using a computer or the like to dispense tablets by actuating the vibrator using the control device illustrated in Figs. 2A and 2B Thus, a detailed schematic diagram of the control circuit 50, tablet detection circuit 80, vibrator 24 and supply transformer are shown in Fig. 2B. However, it will be apparent to a person skilled in the art that the control circuit 50 and tablet detection circuit 80 shown in Fig. 2A can be implemented with modifications without departing from the scope and spirit of the invention.

Furthermore, it is to be understood that the words which have been used are words of description, rather than limitation and that changes can be made without 15 departing from the scope and spirit of the invention.

p p P* p [N:\LIBTT]OO999:MMC The claims defining the invention are as follows:- 1. A tablet dispenser to dispense a predetermined number of tablets, said dispenser comprising: a base; s a tray to receive tablets to be dispensed, said tray being mounted for angular reciprocation about a generally vertical axis and generally vertical reciprocation relative to said base, said tray providing a generally horizontal dispensing path extending angularly about said axis, which path extends to a dispensing outlet in the tray; reciprocation means to cause said vertical and angular reciprocation; means to detect tablets passing through said outlet; and control means to control said reciprocation means so that said tray is moved to dispense a predetermined number of tablets.

2. The dispenser of claim 1 wherein said means to cause said vertical and angular reciprocation includes a vibrator to provide a source of vertical vibration, and resilient means connecting said tray to said vibrator which resilient means which when vertically vibrated cause the angular and vertical reciprocation of the tray.

3. The dispenser of claim 2, wherein said resilient means are resilient strips which extend vertically and horizontally between the vibrator and the tray.

The dispenser of claim 1, 2 or 3, wherein said tray includes a 20 horizontally orientated generally annular path to receive the tablets and along which path the tablets move, said tray having an outlet opening through which tablets are dispensed one at a time to a chute.

0 5. The dispenser of claim 4, wherein said control means further includes means to detect tablets passing down said chute.

6. The dispenser of claim 1, wherein said means to cause vertical and angular reciprocation comprises a permanent magnet, a coil operatively associated with o said magnet and means to deliver a current to said coil to cause vibration thereof, and •means connecting said coil with said tray.

7. The dispenser of claim 6, wherein said control means controls 30 delivery of electric power to said coil to regulate the vertical and angular oscillation of said tray.

8. A tablet dispenser substantially as hereinbefore described with •reference to the accompanying drawings.

*S

DATED this TWENTY-NINTH day of MARCH 1999 Alfonso Segura Patent Attorneys for the Applicant SPRUSON FERGUSON [N:\LIBTT]OO999:mff