WO2004101392A1

WO2004101392A1 - Blister pack dispensing device

Info

Publication number: WO2004101392A1
Application number: PCT/GB2004/002092
Authority: WO
Inventors: Christopher John Hurlstone; Andrew John POCOCK
Original assignee: Team Holdings (Uk) Limited
Priority date: 2003-05-15
Filing date: 2004-05-14
Publication date: 2004-11-25
Also published as: GB0525039D0; GB0311143D0; GB2417484A; GB2417484B

Abstract

A blister pack dispensing device comprising a housing (1) for accommodating the blister pack (5). The housingcomprises a first wall (2) provided with a plurality of apertures (3) arranged to correspond to blisters on the blister pack. A second opposing wall (6) carries at least part of a corresponding plurality of actuating devices(7). Means is provided for changing the state of one or more of the actuating devices (7) between a first state in which on operation it is effective to dispense the contents of a blister (4) and a second state in which on operation it is not effective to dispense the contents of a blister (4). One example of the state changing means is to allow movement of an actuating device in the form of a button (7) from a first state in which the button is in a first position to a second state in which the button (7) is in a second position.

Description

Blister Pack Dispensing Device

The invention relates to a blister pack dispensing device.

There is a requirement for devices to allow safe and simple dispensing of tablets and to prevent as far as possible young children obtaining access but to allow access by older and less dextrous persons, for example those suffering from conditions such as arthritis or whose grip is weak.

Medicines are often packaged in blister packs which comprise a plastic sheet having plurality of moulded receptacles (or blisters) in which one or more tablets are placed covered by a foil which is pierced or burst to obtain access to the contents of the blister. Such blister packs are known in two forms, a standard form with a burstable foil which can be easily "popped" and a child resistant form which has a thicker non-burstable foil. The non-burstable foil is normally peeled off to expose a standard burstable foil. This peeling process may be difficult for persons suffering from arthritis or having a weak grip so cutting tools have been provided to pierce the foil. A more dangerous alternative is to use a pair of scissors.

US-A-51504793 discloses a device for inhibiting removal of an article from a blister-type container having at least one blister. The device includes a housing surrounding at least a portion of the container sized to permit movement of the container between the first and second positions. The housing has a base positioned facing the blister-type container with at least one base opening in registry with the blister when the container is in the first position. The base opening is sized to permit passage of the article therethrough. The device also includes a biasing member for biasing the container toward the second position. When the container is in the second position, the base of the housing is positioned to inhibit removal of the article from the container. When the container is moved by an individual against the bias of the biasing member to the first position, the blister is in registry with the base opening to permit removal of the article by applying pressure to the outside surface of the blister to force the article to rupture the container and pass through the base opening.

US-A-5244081 discloses a device for inhibiting removal of a first article from a first blister-type container having at least one blister. The device includes a first member or second blister-type container positioned facing the first blister-type container with at least one opening in the second container in registry with the blister when the second container in the first position. The first container likewise may include an opening in registry with a second blister of the second container when the second container is in the first position. The openings in the first and second containers are sized to permit passage of the respective articles therethrough^'. When the second container is in the second position, the second container is positioned to inhibit removal of a first article from the first container and the first container is positioned to inhibit removal of a second article from the second container. The device may also include a first member for permitting movement of the second container between the first and second positions and a second member for maintaining the second container proximate the container and permitting movement of the second container between the first and second positions. A locking member may be provided for locking the containers in the second position.

The invention provides a blister pack dispensing device comprising a housing for accommodating the blister pack, the housing comprising a first wall provided with a plurality of apertures arranged to correspond to blisters on the blister pack, a second opposing wall carrying a corresponding plurality of actuating devices, and means for changing the state of one or more of the actuating devices between a first state in which, on operation, it is effective to dispense the contents of the blister and a second state in which, on operation, it is not effective to dispense the contents of a blister.

Our co-pending PCT application PCT/GB2002/OO5149 describes a blister pack dispensing device comprising a housing for accommodating the blister pack, the housing comprising a first wall provided with a plurality of apertures arranged to correspond to blisters on the blister pack, a second opposing wall carrying a corresponding plurality of buttons or actuating devices, and a manually operable locking mechanism for enabling or disabling depression of the buttons, the locking mechanism comprising a moveable stop member, the stop member being moveable between a first position in which one or more of the buttons is/are enabled to be operated to dispense the contents of a blister through an aperture and a second position in which the button is prevented from being operated to dispense the contents of the blister.

The present invention provides an alternative to that described in our co-pending application. The principle of the present invention is to change the state of the actuating devices between a first state where on depression of at least part of an actuating device it collapses the blister to eject the contents of the blister and a second state where on depression it is not effective to collapse the blister; rather than preventing or enabling depression of buttons.

The actuating device may comprise a button, wherein in the first state the button is in a first position and in the second state the button is in a second position.

Thus as compared with our co-pending application PCT/GB2002/005149 the button is moved between a first position where on depression it causes a blister to collapse and a second position where on depression it does not cause the blister to collapse rather than being allowed or prevented from being fully depressed.

The button may move along a fixed path that may be defined by a slot and may be a linear path. An alternative form of movement is to rotate the button between the first and the second position.

A biassing means may be provided to bias the button towards the second position. The biassing means may be separately provided for each button or may act on a plurality of buttons simultaneously.

While providing a biassing means which operates on a plurality of buttons simultaneously may enable the dispensing device to be constructed from fewer components there may also be operating advantage in reducing the number of buttons which may be operated when the biassing means is brought in to play. Thus, if the biassing means enables the operation of a single button only this prevents a plurality of tablets of being dispensed with a single operation of the biassing means. This makes it more difficult for a child to gain access to the tablets in a large number of the blisters making the packaging safer. In normal use it would be unusual to require the dispensing of the contents of a large number of blisters at one time .

The actuator may be of a form in which it has a first shape when in the first state and a second shape when in the second state.

The means for changing the state of the actuating device may comprise a button having an inflatable portion and means for inflating or deflating the inflatable portion, the button on depression being capable of dispensing the contents of the blister only when the inflatable portion is inflated.

The actuation device may further comprise a fluid reservoir that intercommunicates with the inflatable portion and the state changing means may comprise means for pumping the fluid to or from the inflatable portion. The fluid may be substantially incompressible.

This comprises a convenient method of changing the shape of the actuator.

In a further embodiment of the invention the actuating device comprises a button for depression by a user, an interposing member, and means for moving the interposing member between a first position where it is located between the button and the blister and acts against the blister to dispense the contents thereof when the button is depressed and a second position where depression of the button is not effective to cause the interposing member to act against the blister. A single interposing means may enable a plurality of actuating means simultaneously.

Thus, according to the invention an actuating device is caused to change from a first state in which it can be operated to dispense the contents of a blister and a second state in which it cannot. Examples of this change of state include changing the position of at least a portion of the actuating device and changing the shape of at least a portion of the actuating device. The shape change can be achieved in a number of ways. For example, the actuator device may include an inflatable portion that causes an increase in the size of the actuator on inflation. This increase may enable the actuator device to dispense the contents of a blister by enabling it to collapse the blister only when inflated. An alternative method of changing the shape of the actuator device would be to provide a means, for example electromechanical, for adding a member to the actuating device in order to change its shape. A further example of changing the shape of the actuating device is shown in Figure 9 where the actuating device comprises the combination of the buttons and the flexible arm. The position change may also be obtained in many ways. Examples are by linear or curved motion and rotation.

The above and other features and advantages of the invention will be apparent from the following description, by way of example, of embodiments of the invention with reference to the accompanying drawings, in which:

Figure 1 illustrates a first embodiment of a blister pack dispensing device according to the invention; Figure 2 illustrates a second embodiment of a blister pack dispensing device according to the invention;

Figure 3 is a perspective view of a third embodiment of a blister pack dispensing device according to the invention;

Figure 4 is a cross-section on line X-X of Figure 3;

Figure 5 illustrates one form of moving means which operates on a plurality of buttons simultaneously.

Figure 6 shows a fourth embodiment of a blister pack dispensing device according to the invention;

Figure 7 shows a fifth embodiment of a blister pack dispensing device according to the invention;

Figure 8 shows a sixth embodiment of a blister pack dispensing device according to the invention; and

Figure 9 shows a seventh embodiment of a blister pack dispensing device according to the invention.

Figure 1 shows a first embodiment of a blister pack dispensing device according to the invention. Figure la is a perspective view of the dispensing device while Figures lb and lc are cross-sections on line X-X of Figure la, Figure lb showing the actuating device in the first state and Figure lc showing the actuating device in the second state. As shown in Figure 1 the blister pack dispensing device comprises a housing 1 having a first wall 2 provided with a plurality of apertures 3 arranged to correspond to blisters 4 on a blister pack 5 which is located within the housing 1. A second opposing wall 6 carries a corresponding plurality of actuating devices 7 in the form of buttons which are carried on a flexible member 20. The walls 2 and 6 are joined at one end by a further wall 8 and at the other by a wall 9. The flexible member 20 hinges about a point 21 near to the junction of the wall 6 and wall 9 and carries a slot 12 along which the actuating member 7 is slidable. A first projection 10 on the flexible member 20 engages with a second projection 11 at the junction of the walls 2 and 8 and defines the maximum depression of the actuating member 7 and flexible member 20.

It will be seen that with the actuating member 7 in the position shown in Figure lb depression of the actuating member will cause it to come into contact with the blister 4 on the blister pack 5 and further depression will cause the ejection of the contents of the blister 4 through the aperture 3. The flexible member 20 flexes about the point 21 and the extent of the movement is defined by the projections 10 and 11. When the actuating member 7 is in the position shown in Figure lc depression thereof will not cause it to come into contact with the blister 4 and while the flexible member 20 may be depressed the actuating member will not be effective to dispense the contents of the blister. Thus the actuating member 7 moves between a first position as shown in Figure la which corresponds to a first state of the actuating device and a second position as shown in Figure lb which corresponds to the second state of the actuating device. In the first state it is effective to dispense the content of the blister while in the second state it is not. In this embodiment the actuating member comprises the button 7 and the flexible member 20. In the state where the button 7 is aligned with the blister 4 depression of the button is effective to dispense the contents of the blister. In the state where the button 7 is not aligned with the blister 4 depression of the button 7 (or the flexible member 20) it is not effective to dispense the contents of a blister.

There are no biassing means shown in this embodiment to ensure that the button is normally held in the position shown in Figure lc. It would be preferable to add such a biassing means so that one or more of the buttons 7 is/are not inadvertently located in the first position shown in Figure lb and hence able to dispense the contents of the blister without requiring the button to be slid from the second position, that is without requiring to separate actions by the user. There are many possible ways to provide a biassing means. One possible implementation is a compression spring in the slot 12 acting between the button 7 and the end of the slot 12 furthest from the pivoting point 21.

A further limitation of this particular construction is that the dispensing device has to be made significantly wider than the blister pack that is contained within it so that there is space for the button when in the non- operating or second position.

Figure 2 shows a second embodiment of a blister pack dispensing device according to the invention which is similar in concept to that shown in Figure 1 and the same reference signs are used to illustrate corresponding features . In the embodiment shown in Figure 2 the button 7 slides from the opposite side of the blister 4 from the embodiment shown in Figure 1. The embodiment of Figure 2 also shows a biassing means in the form of a bias element 15 which is moulded as part of the button 7. The bias element 15 causes the button to return to a ^Λhome'^' position which is as shown in Figure 2a, that is to the left of the blister 4. In this embodiment the projections 10 are provided with recesses into which the button 7 can be located when in its second position. Thus, the embodiment of Figure 2 includes a biassing means 15 to ensure that it is necessary to hold the button 7 in the first position as well as to depress it to eject the contents of the blister. In addition, the space required on the hinge side 9 of the dispensing pack to enable the button 7 to be located in the second position is eliminated. Space at that side is merely required to enable the biassing means 15 to operate. Other biassing mechanisms may well take up less space than that shown for the particular biassing means 15 shown in Figure 2, act at the other side of the button 7, or within the slot 12 and enable a more compact form of dispensing device.

Figure 3 is a perspective diagram of a third embodiment of a blister pack dispensing device according to the invention, while Figure 4 is a cross-sectional view of line Y-Y of Figure 3. As shown in Figures 3 and 4, a blister pack dispensing device 30 comprises a first wall 32 having a plurality of apertures 33 which are aligned with blisters 34 on a blister pack 35. An opposing wall 36 carries a plurality of flexible members 37 that are hinged from the outer portion of the wall 36 where it joins the first wall 32. • An assembly 38 which carries first and second actuators 39 and 40 and button 41 forms a moving means which moves the actuators 39 and 40 between a first position and a second position. In the first position, which is shown in Figure 4b, the moving means 41 is depressed in the direction of the arrow 42 and on depression of a flexible member 37 the actuators 39 or 40 will cause deformation of the blisters 34 and eject the contents of that blister through the associated aperture 33. In the second position, which is shown in Figure 4a, depression of a flexible member 37 will cause the actuator 39 or 40 to rotate in the direction of the arrows 42 and not come into contact with the surface of the blisters 34. Hence the contents of the blister will not be dispensed through the aperture 33 when the actuator 39 or 40 is in the second position.

In this embodiment the actuating devices comprise the assembly 38 and the flexible members 37 and the first state corresponds to the position shown in Figure 4a where the button 41 is depressed while the second state corresponds to the position shown in Figure 4b where the button 42 is not depressed.

It will be appreciated that the height of the dispensing device has to be sufficient to allow the actuators 39, 40 to remain clear of the blisters when the tabs 37 are depressed. The device of Figures 3 and 4 is designed for dispensing the contents of blister packs where the blisters are arranged in two rows.

As shown in Figures 3 and 4 each pair of buttons is carried by a separate moving means 38. This has the advantage that only one pair of flexible members 37 will be operative to dispense the contents from the blisters. In addition, each member of the pair is located on a different side of the dispenser and thus it is relatively difficult to dispense from both apertures at the same time, since this requires three separate operations, that is depression of the button 41 and two separate flexible members 37 that are located on opposite sides of the button 41. In this way the accidental dispensing of more than one blister will be less likely to occur. Figure 5 shows a mechanism which could be used to enable all the actuating members 41 shown in Figure 4 to be operated simultaneously should there be a desire to enable the contents of any of the blisters to be dispensed at one time. The mechanism comprises a rod-like member 50 which has a number of inclined projections 51. The assembly 38 that carries actuators 39 and 40 on which the flexible members 37 operate has the button 41 replaced by a projection 45 having an inclined upper portion 53 that engages with the corresponding inclined projections 51 when the rod-like member 50 is moved from left to right as shown by the arrow 54 in Figure 5. This gives the same effect as depressing the button 41 in the embodiment of Figures 3 and 4 but will enable all of the actuators 39 and 40 simultaneously. This gives access to any of the blisters with only one movement of the rod-like member 50. The member 50 may be arranged to slide within the dispensing device 30 and project from one end thereof. The inclined projection 51 would provide some restoring force but additional biassing means may also be provided, for example a compression spring bearing on the opposite side of the wall from that from which the rod-like member 50 projects. Further the projections 51 may have an alternative profile. Only one of the projections 51 and 45 needs to be provided with an inclined surface over which the other can ride to provide a force having a component perpendicular to the movement of the member 51. There are, of course, many other ways of converting linear motion into motion having a component perpendicular thereto such as gears, cams, etc. In addition, the rodlike member could be arranged to rotate rather than move linearly to provide the necessary force to cause the assembly 38 to move between the first and second states. Figure 6 shows a fourth embodiment of a blister pack dispensing device according to the invention. Figure 6a is a perspective view of a dispensing device 60 having a conical upper wall 61 carrying a plurality of flexible members 62. A lower wall (not shown) has a plurality of apertures through which blisters from a blister pack housed within the housing 60 may be dispensed. An assembly 64 as shown in Figure 6b, which is equivalent in form to the assembly 38 of the embodiment of Figure 3, comprises a plurality of arms 65 which terminate in actuators 66. A button 67 is provided which projects through an aperture at the apex of the cone-shaped wall 61.

In operation the button 67 is depressed and the flexible member 62 can then depress the actuator 66 against a blister of the blister pack housed within the housing 60 in a similar manner to that shown in and described with reference to Figures 3 and 4. It will be seen in this embodiment that the actuating device comprises the assembly 64 and the flexible members 62. In the first position where the button 67 is depressed the actuating device is effective to dispense the contents of a blister when the flexible member 62 is depressed and this is the first state of the actuating device. The second state of the actuating device corresponds to the situation where the button 67 is not depressed in which case depression of the flexible member 62 will not be effective to dispense the contents of a blister since the actuator 66 will remain out of contact with the blister. Figure 6c shows a similar construction to that shown in Figures 6a and 6b with the exception that the single button 67 is replaced by separate buttons for each of the blisters. Thus depression of a flexible member 62 will only be effective if the corresponding button 67 is also depressed at the same time. This has the effect of moving the actuator 66 into alignment with the blister when depressed by the actuating member 62 when the button 67 is depressed or causing it to be out of alignment with the blister when the button 67 is not depressed.

As can be seen from the embodiment of Figure 6 it is not necessary that the blisters are arranged in straight lines on the blister pack. In practice, embodiments can designed which will enable the blister pack dispensing device to dispense blisters from blister packs of any arbitrary shape. The only constraint is that it must be possible to align individual actuators with the individual blisters and to be able to change the state of the actuating device so that it can be changed from the first to second state.

Figure 7 illustrates a fifth embodiment of a blister pack dispensing device according to the invention. This embodiment is similar to those shown in Figures 1 and 2 and corresponding elements thereof will be given the same reference signs. As shown in Figure 7 an actuator 70 is mounted on the flexible member 20. In this embodiment the actuator 70 is rotated about an axis 71. The actuator 70 is asymmetric and when rotated to the position shown in Figure 7a on depression of the flexible member 20 the surface of the actuator will project sufficiently far below the flexible member 20 that it collapses the blister on depression of the flexible member 20 and ejects the contents through the aperture 3. In the position shown in Figure 7b the actuator 70 does not project sufficiently below the flexible member 20 to enable it to compress the blister. The extent of depression of the flexible member 20 is determined by the projections 10 and 11. Thus in this embodiment the actuating device is the flexible member 20 and actuator 70 and in the first state shown in Figure 7a it is effective to dispense the contents of a blister 4 and in the second position is not effective to dispense the contents of the blister 4. The first position of the actuator 70 corresponds to the first state of the actuating device while the second position of the actuator 70 corresponds to the second state of the actuating device.

Figure 8 illustrates as sixth embodiment of a blister pack dispensing device according to the invention. The form of the sixth embodiment is similar to that of the fifth embodiment and features corresponding to those in the fifth embodiment have been given the same reference signs. The main difference between the fifth and sixth embodiments is in the form of the actuator. As shown in Figure 8 the actuator 80 is capable of changing shape. Thus in the shape shown in Figure 8a depression of the flexible member 20 will cause the lower surface of the actuator 80 to contact the upper surface of the blister 4; further depression of the flexible member 20 will cause the actuator 80 to collapse the blister 4 and eject the contents of the blister through the aperture 3. When the actuator 80 takes the form shown in Figure 8b the lower surface of the actuator 80 fails to collapse the blister 4 even at maximum depression of the flexible member 20. The maximum depression of the flexible member 20 is defined by the projections 10 and 11.

A convenient method of causing the actuator 80 to change shape is to form a chamber within the actuator 80 which has flexible walls and to pump a fluid into the chamber to expand the actuator 80 to the form shown in Figure 8a. It is preferable that the fluid that is pumped into the chamber in the actuator 80 is relatively incompressible. The method of pumping the fluid into the chamber may simply be a bulb which is pressed by the user when wishing to eject the contents of a blister. Thus the two operations of pressing the bulb to expand the actuator 80 and then depressing the flexible member 20 provides an element of child resistance to the dispensing of the contents of the blister pack. In this embodiment the first state of the actuating device is as shown in Figure 8a and the second state the different shape shown in Figure 8b. Thus the actuating device changes shape to enable or disable the dispensing of the contents of a blister.

Figure 9 shows a seventh embodiment of a blister pack dispensing device according to the invention. Figure 9a is a plan view of the dispenser while Figure 9b is a cross-sectional view on an enlarged scale on line Z-Z of Figure 9a. The dispensing device comprises a housing 90. The housing 90 comprises a first wall 91 having a plurality of apertures 92 arranged to correspond to blisters 93 on a blister pack 94 contained within the housing 90. A second opposing wall 95 carries a corresponding plurality of buttons 96 aligned with the apertures 92. Two side walls 97 and 98 join the two walls 91 and 95 to form the housing 90. A slider 100 is mounted on the wall 95 in a slot 99. The buttons 96 are arranged in pairs and the slot 99 is arranged between the pairs. The slider 100 is provided with two flexible arms 101 and 102. When the slider 100 is aligned with a pair of buttons 96 the flexible arms 101 and 102 are interposed between the bottom of the buttons 96 and the top of the blisters 93. With the slider in this position depression of one of the pair of buttons 96 against a restoring device 103 will cause the button to force the flexible arm 101 or 102 against the corresponding blister 93 and cause the contents of the blister to be dispensed through the corresponding aperture 92. The travel of the buttons 96 is such that the bottom of the button will not cause the blister 93 to collapse if the flexible arms 101 or 102 are not interposed between the buttons and the blister. Thus the flexible arms 101 and 102 effectively form a further part of the buttons 96 which may be present or not present depending on where the slider is along the slot. Thus the actuating device comprises the button 96 and the flexible arms 100 or 101 and will change state depending on the position of the slider 100. It is advantageous to provide a rest position for the slider 100 where it is not aligned with any of the buttons 96 and preferably the slider 100 should be biassed towards that position. Thus movement of the slider is required in addition to depression of a button 96 in order to dispense the contents of a blister through the corresponding aperture 92. As shown in Figure 9a the slot 99 extends to a portion of the housing where no buttons 96 are provided. This provides a "rest" or non-operative position for the slider 100 where depression of any of the buttons 96 will have no effect in dispensing the contents of a blister. This "rest" or non-operative position could be provided at other points on the housing, for example in a space between the buttons 95.

Clearly the embodiment of Figure 9 could be modified by providing a dispenser for a single row of blisters on a blister pack, in that case only one flexible arm 101 or

102 would be required on the slider 100. In addition, the slot 99 need not be linear, it could take any desired shape depending on the layout of the blisters on the blister pack. In a further modification the housing 90 could be made circular in plan. In this case the slider 100 would be replaced by a rotatable device carrying arms 101 and/or 102 in a similar manner, the housing being rotated relative to the rotatable device to align a particular button 96 with the flexible arm 101 or 102 to enable dispensing of the contents of the blister. Again it would be preferable for the rotatable device to be biassed to an off" position where it is not aligned with any of the buttons 96.

It will be apparent to the skilled person that many arrangements of blisters on a blister pack can be accommodated by appropriately modifying the action and location of the activating devices and that the above described embodiments are only particular examples. Other configurations will be readily apparent to the skilled person and fall within the scope of the appended claims. In addition there are many possible arrangements for changing the positions and/or shapes of the actuating devices in addition to those shown in the embodiments that will be readily apparent to the skilled person and the scope of , the claims is not limited to the arrangements described in the embodiments. These are merely examples of possible arrangements.

Claims

1. A blister pack dispensing device comprising a housing for accommodating the blister pack, the housing comprising a first wall provided with a plurality of apertures arranged to correspond to blisters on the blister pack, a second opposing wall carrying at least part of a corresponding plurality of actuating devices, and means for changing the state of one or more of the actuating devices between a first state in which on operation it is effective to dispense the contents of a blister and a second state in which on operation it is not effective to dispense the contents of a blister.

2. A device as claimed in Claim 1 in which the actuating device comprises a button, wherein in the first state the button is in a first position and in the second state the button is in a second position.

3. A device as claimed in Claim 2 in which the button moves along a fixed path between the first and second positions.

4. A device as claimed in Claim 3 in which the fixed path is linear.

5. A device as claimed in Claim 2 in which the button rotates from the first to the second position.

6. A device as claimed in any of Claims 2 to 5 in which the buttons are biassed towards the second position.

7. A device as claimed in Claim 6 comprising biassing means that operates on a plurality of buttons simultaneously.

8. A device as claimed in any preceding claim comprising moving means for moving at least part of the actuating means from the first to the second position.

9. A device as claimed in Claim 8 in which the moving means operates on a plurality of actuating means simultaneously .

10. A device as claimed in any preceding claim arranged to accommodate a blister pack having blisters arranged in pairs to form two rows, wherein the moving means operates separately on each pair of actuating devices

11. A device as claimed in any of Claims 8 to 10 in which the moving means forms part of the actuating device.

12. A device as claimed in Claim 1 in which in the first state the actuator has a first shape and in the second state the actuator has a second shape

13. A device as claimed in Claim 12 in which the means for changing the state of the actuating device comprises a button having an inflatable portion and means for inflating or deflating the inflatable portion, the button on depression being capable of dispensing the contents of the blister only when the inflatable portion is inflated.

14. A device as claimed in Claim 13 in which the actuation device further comprises a fluid reservoir that intercommunicates with the inflatable portion and the state changing means comprises means for pumping the fluid to or from the inflatable portion.

15. A device as claimed in Claim 13 or Claim 14 in which the fluid is substantially incompressible.

16. A device as claimed in Claim 1 in which the actuating device comprises a button for depression by a user, an interposing member, and means for moving the interposing member between a first position where it is located between the button and the blister and acts against the blister to dispense the contents thereof when the button is depressed and a second position where depression of the button is not effective to cause the interposing member to act against the blister.

17. A device as claimed in Claim 16 in which a single interposing means enables a plurality of actuating devices simultaneously.

18. A device as claimed in any preceding claim wherein the actuating device comprises a button, the button being carried on a flexible member.