GB2436559A

GB2436559A - Tablet dispenser

Info

Publication number: GB2436559A
Application number: GB0605104A
Authority: GB
Inventors: Terence Edward Weston
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-03-15
Filing date: 2006-03-15
Publication date: 2007-10-03
Also published as: GB0605104D0

Abstract

A device for dispensing tablets and capsules from blister packs, comprising a resilient clip 3 with a hole 6 to locate and retain an individual blister, a punch portion 5 on a resilient cantilever arm 4 and a base member 2 comprising a die 7. The top surface of the base around the die has a depression 9, generally of concave form, which encourages the backing sheet of the blister to stress under tension when pressure is applied by the punch head on the tablet compartment 10. The cantilever arm may be fixed at the same end as the resilient clip or made as an extension of it as shown in Fig.4. A further accessory to provide more leverage or mechanical advantage is shown in Fig.3

Description

ackground to the invention.

Many products are made in capsule and tablet form, and packed individually in blister packs -for example, pharmaceutical tablets and capsules are usually packed this way.

The most familiar form of blister pack is that where a blister or bubble shape is formed in a thin plastic sheet to contain the tablet, and a flat sheet of frangible thin metal foil, paper, or plastic, is sealed against the base of the blister to retain the tablet and prevent ingress of contaminants. Typically, the whole pack will comprise a number of blisters bonded to the backing sheet. To remove a tablet, the user presses on the blister to deform it and force the tablet to rupture the flat foil backing sheet and thus be released from the pack. However, whilst this packaging method has a number of advantages in maintaining the integrity of the contents, for many users, particularly the elderly, it can be difficult to dispense a tablet. This is because the user must press fairly accurately on the blister without pressing on adjacent blisters, and at the same time as supporting the flat side of the pack closely to the rupture area from where the tablet is to be dispensed. In fact, if the dispensing action is watched carefully, most users also bend the backing sheet, which puts it in tensile stress -in other words, bending the pack stretches the backing sheet. By pre-stressing the backing sheet this way, it is easier to rupture it by the small additional force created by pressing the tablet against it, and the backing sheet tears to form a flap which remains attached to the sheet.

A number of devices have been invented to assist in dispensing tablets. For example, WO 03042066A1 discloses a device in which the sheet of blisters is placed in a housing having an array of push-buttons aligned with the blisters. To dispense a tablet, the user merely presses one of the buttons, which punches the tablet from its blister. A drawback of this device is that it must be dedicated to a particular array of blisters. There are no standards for pitch, size and number, so it is impossible to design a universal dispenser on this principle. Again, US 4,627,432 (Newell et al) discloses a dispenser which requires the blister pack to be circular, and clearly, the device and the blister pack must be designed to be dedicated. One thing all have in common is the use of a punch, other examples being. US 4,428,709 (Peters), US 5,009,561 (Lombardino et al), and US 5,472,115 (Whiton). The device disclosed by Whiton is in effect a universal dispenser in that it will punch a tablet from most sheets of blisters, regardless of pitch or sheet size. However, that device is relatively large and expensive. Many prior art devices include some means of increasing the mechanical advantage, because the force required to rupture the backing sheet by applying a straight push on the blister is fairly high -US 5,472,115 is a typical example, where pliers have been adapted to provide a punch and die to dispense individual tablets. Part of the reason for the high punch force needed with most of these devices is that the punch is designed to shear the backing sheet crudely by pushing the tablet onto it, and trying to shear the entire area of the backing sheet supporting the blister.

Because of the size and or complexity of the prior art devices, they are not in common usage, although clearly there is a demand for such. And if the dispensing aid is made sufficiently small and inexpensive, it could be packed with the blister pack as a throwaway tool.

The present Invention The present invention seeks to overcome the drawbacks of the prior art by providing a device having means for bending the pack to create a tensile stress in the backing sheet, and a means for punching the tablet out from the blister and eject it through the ruptured backing sheet. A lower force is required if the backing sheet is torn by pressing the tablet at an angle, and by this combination of bending and punching at an angle, little or no additional mechanical advantage is required, and the design of the device is simplified to the extent that it can be manufactured as a single part, with the consequent benefits of low cost.

In a first embodiment, there is provided a tablet dispenser comprising a backing sheet, blister location clip and punch, whereby the backing sheet has a concave area that allows the blister pack to be bent so as to stress the backing sheet when the punch engages with the blister.

In a second embodiment, a similar device to the first embodiment is provided, together with a frame into which the dispenser is placed, thereby to provide even easier operation, particularly for those people who have disabilities or difficulty in operating small tools.

A further embodiment is a tablet dispenser which has an offset punch to ensure that the blister and tablet are tilted to press on a small area of the backing sheet, thus reducing the force required to tear the backing sheet and dispense the tablet.

The invention will now be described in detail, with reference to the following drawings.

Figures Ia, 1 b,and Ic are a general arrangement, with figure lb as a centre-line section; figure Id is a section through a single blister containing a tablet.

Figure 2a, 2b and 2c show the sequence of loading a blister pack into the device and punching a tablet out of the blister and through the backing sheet.

Figure 3 is a schematic showing how the dispenser may be fitted into a fram having a lever to increase the mechanical advantage.

Figures 4a,4b,4c and 4d illustrate the sequence of dispensing a tablet from a blister pack, where the punch is offset to positively tilt the blister and tablet, so as to more easily rupture the backing sheet. This embodiment also shows a simple receptacle to hold the tablet after dispensing.

Like parts are given like annotation where possible. For the purposes of clarity, the terms punch and die will be used throughout, because this is the basic operating principle.

Figures 1 a to Ic are a general arrangement, and referring to figure Ia, this is a top view of the dispenser, looking onto the operating arm 4. Figure lb is a centre-line section, and figure 1 c is an underneath view. Referring to figure 1 b, the dispenser comprises a base 2, attached to a resilient cantilever operating arm 4, and having the punch 5 located at the free end of the arm 4. Approximately axial to the punch 5 is a die 7 in the base 2. The top surface of the base 2 around the die 7 has a depression 9.

Located between the base 2 and the arm 4 is a resilient cantilever clip 3, which has a blister-locating hole 6 positioned approximately axially with the punch 5 and the die 7. To enable the blister pack to be fed easily into the dispenser, the free ends of the base 2 and the clip 3 are configured to provide a tapering guide 8. For economic manufacture, the dispenser may be moulded in a resilient plastic as a one-piece moulding, although it could be feasible to make it from more parts -to have interchangeable punches and dies for example.

Figure I d is a section through a single blister, comprising a backing sheet II, which is bonded to a thin walled blister 10. The tablet or capsule 12 to be dispensed is located within the cavity of the blister 10. Normally a number of blisters bonded to a common backing sheet would be supplied, but the present invention is capable of dispensing a tablet from a sheet having a single blister.

The operating sequence is illustrated in figures 2a, 2b and 2c. In figure 2a, the blister pack ld is shown being fed through the guide 8 in the direction of the arrow X, so that the blister 10 displaces the resilient clip 3 away from the base 2. The blister pack I d is pushed in further until the blister enters the hole 6, and this allows the resilient clip 3 to snap back towards the base 2, thereby holding the blister 10 of the blister pack id in approximate axial alignment with the punch 5 and the die 7. Figure 2c shows the action of pressing in the direction of the arrow Y relative to the base 2, which forces the punch to press on the blister. The initial part of this action partly collapses the blister 10, and also stretches the backing sheet 11 of the blister pack 1 Od into the depression 9. Continuing the action causes the tablet 10 to press against the backing sheet 11 until it ruptures. The tablet will then fall from the hole thus formed in the backing sheet. In summary, the action of stretching the backing sheet 11 into the depression 9 in the base 2 lowers the force necessary to rupture the backing sheet 11.

The aged or physically handicapped person can still have difficulty in manipulating the dispenser, and to make the process easier, a simple press as shown in figure 3 may be provided. A base 13 has a has an arm 15 freely pivoted at 16. The device already described by figures 1 and 2 is removably inserted into the press, so that the arm 15 engages with the cantilever arm 4. The arm 15 is longer than the arm 4, which provides a useful mechanical advantage -that is, the force required to punch the tablet from the blister will be lower. The blister pack 1 d is loaded as described earlier, and by pressing on the arm 15, the tablet will be dispensed as described. In this case, it would be useful to provide a drawer 14 or other receptacle to catch the tablet(s) as they are dispensed. By making the base 13 a substantial size and fitting non-slip feet to the underside, the arrangement shown in figure 3 will greatly ease the use of the dispenser, and even facilitate single-handed operation.

Figures 4a, 4b, 4c, and 4d show another embodiment of the invention whereby a base 2 has a resilient cantilever arm 3 attached, which continues at its free end with an operating arm 16, folded back towards the attachment of the cantilever arm 3 to the base 2. The base 2 has a die 7 therein, and a depression 9, and the resilient arm 3 has a hole 6 approximately axially aligned with the die 7 in the base 2. The operating arm 16 has a punch 18, which is offset from the axis of the die 7, but still positioned within the perimeter of the die 7. The base 2 has a boss 19 to which is clipped or frictionally attached a receptacle 17. The sequence of operation is similar to that described by figures 1 and 2, so figure 4a shows the blister pack 1 d being pushed in the direction of the arrow X into the guide area 8 formed between the resilient arm 3 and the base 2, so that the blister 10 pushes the resilient arm 3 away from the base 2.

As shown in figure 4b, further insertion of the blister pack I d causes the blister 10 to enter the hole 6 in the resilient arm 3, and the resilient arm 3 snaps back towards the base 2, thus retaining the blister 10 approximately axially aligned with the die 7.

Referring to figure 4c, by acting on the resilient aim 16 in the direction of the arrow Z, the punch 18 contacts the blister 10 to one side of the axis, and initially stretches the backing sheet 11 of the blister pack Id into the depression 9 in the base 2. Further movement of the punch depresses one side of the blister 10 and tilts the tabletl2, and the tablet 12 and the lower periphery of the blister 10 tear the backing sheet 11 on one side. Fully pressing the arm 16 pushes the tablet 12 further through the tear in the backing sheet 11, and the tablet 12 becomes free to drop into the receptacle 17. It is possible to increase the mechanical advantage of this embodiment by increasing the ratio A:B of the operating arm 16.

The depression 9 in the base 2, which is common to all embodiments, may be curved as shown, or V-shaped, or a rectangular notch, to suit the characteristics of the backing sheet.

All of the forgoing examples depict a dispenser for dispensing round tablets, but the shape of the punch and die may be altered to suit elongate tablets or capsules, or indeed, any other shape, such as rectangular, or polygonal.

Although the devices described are intended for high volume manufacture, preferably as a one-piece construction, such as a plastic moulding, or a metal pressing, it is possible to make the device from more than one part. Equally, the resilient arms may be replaced by very rigid parts, and the resilience may be provided by separate springs. Devices made from plastics may be advantageously moulded in transparent plastic, to facilitate visual alignment and insertion of the blister pack.

Claims

Patent application GB 0605104.9 Claims 1 A device for dispensing

tablets and capsules from blister packs comprising a resilient clip to locate and retain an individual blister and means for stressing the backing sheet of the blister pack and a resiliently biased punch for pressing the tablet through the backing sheet and then through a hole in the base of the device 2 A device as in claim I where the means for stressing the backing sheet is a concave area within the base which is aligned with the hole in the base into which concave area the backing sheet is pressed at the start of the dispensing procedure 3 A device as in any preceding claim where the resiliently biased punch is aligned with asymmetrically with the blister and tablet therein 4 A device as in any preceding claim where the clip punch and base are made integrally A device as in claims 1 to 3 where the clip punch and base are made separately and then assembled 6 A device as in any preceding claim where a receptacle is provided for holding the tablet or tablets dispensed 7 A device as in any preceding claim where there is provided apparatus to be used in conjunction with the dispensing device to increase the mechanical advantage 8 A device according to any preceding claim which is made entirely of a plastics material 9 A device according to any preceding claim which is made entirely from metal A device as in any preceding claim which is made from a combination of metal and plastics material