TABLET DISPENSER

Abstract: Tablets are dispensed one at a time from a dispenser in which the tablets are randomly orientated in a reservoir (29) and pass first into a triangular chamber (10), and then along a passageway (15) of such a width that only a single column of abutting tablets can be accommodated. The chamber and passageway are formed in an inner member (5) which moves from a first non-dispensing position to a second dispensing position within the casing of the dispenser. When the inner member moves from the first to the second position, the lowermost tablet in the passageway enters a gate and from there falls into a predispensing chamber as the inner member is urged towards its first position by a spring 6. When the inner member is again moved to the second position the tablet in the predispensing chamber is dispensed.

Description: The present invention relates to containers for the storage and dispensing of tablets. Such containers are hereinafter referred to as dispensers and are intended to dispense the tablets contained therein one at a time. The dispenser may be used for medicinal tablets or for tablets containing an artificial sweetening agent, for example, saccharin or aspartame. In order that the medicinal dose or the degree of sweetening can be controlled, a dispenser is required which dispenses tablets one at a time. The present invention aims to provide such a dispenser. US-A-4230236 describes tablet dispensers which comprise an outer casing containing a reservoir for holding tablets to be dispensed, a slidable inner member which has means to transfer tablets from the reservoir into a dispensing passageway from where they pass to tablet controlling means which allow a single tablet to pass into a dispensing gate when the slidable inner member is moved into the outer casing and then allows the tablet to be dispensed when the inner member is moved to a second position. EP-A-93087 describes a tablet dispenser in which a tablet is transferred from a reservoir to a dispensing passageway and then into a predispensing chamber from which it is dispensed when a slidable inner member is moved into the outer casing. The present invention relates to a dispenser for dispensing tablets one at a time which comprises (a) an outer casing containing a reservoir in which the tablets are randomly orientated, (b) a slidable inner member which slides within the outer casing from a first non-dispensing position to a second tablet-dispensing position and which is urged towards its first position by a spring member (6), (c) means on the slidable inner member for causing tablets to be transferred from the reservoir and to become arranged in a single layer in a chamber which feeds the tablets into a dispensing passageway which is of such a width that only a single column of abutting tablets can be accommodated, (d) tablet-controlling means fixed relative to the outer container which retain the lowermost tablet in the dispensing passageway when the slidable inner member is on its first position and which comprise a gate into which said lowermost tablet passes when the slidable inner member is in its second position, characterised in that the dispenser comprises a predispensing chamber (33) in which the lowermost tablet is stored after it has passed into said gate, said tablet entering the pre-dispensing chamber as the slidable inner member moves from the second to the first position and tablet-retaining means which retain said tablet in the predispensing chamber when the slidable inner member is in its first position but permit the tablet to be dispensed when the slidable inner member is in its second position said dispenser being and in that the slidable inner member is provided with a channel running parallel to the direction of movement of the slidable inner member, said channel facing a second inner member fixed in position within the outer casing, said channel receiving therein elongate projections extending from the central wall of the second inner member to guide the inner member as it slides between its first and second positions and the channel is provided on its base with a wedge shaped projection, the scarp face of which contacts one of the elongate projections when the slidable inner member is in its first position. Preferably the slidable inner member comprises (a) a sloping ramp surface (b) a generally triangular chamber at the lower end of the ramp surface defined between a lower central wall of the slidable inner member, a central wall of the second inner member and projections extending from the central wall of the slidable inner member towards the second inner member, the separation between the central walls of the two inner members being such that only a single layer of tablets can be accommodated in the chamber and (c) a dispensing passageway extending downwardly across the face of the central wall of the slidable inner member leading to the gate, said passageway being defined by said central walls and by projections extending from the central wall of the slidable inner member towards the second inner member. One of the elongate projections may extend into the chamber to agitate the tablets therein when the slidable inner member is moved between its first and second positions. The gate may be formed between two gate-forming projections extending from the central wall of the second inner member, the gate-forming projections being positioned so that when the slidable inner member is in its first position one of the gate-forming projections at least partially occludes the passageway preventing the egress of the lowermost tablet from the passageway and when the slidable inner member is in its second position the lowermost tablet in the passageway passes into the gap between the gate-forming projections. The slidable inner member may be provided with a downwardly directed projection which extends into the aperture in the base of the outer casing through which tablets are to be dispensed, said downwardly-directed projection being provided with a tablet-retaining projection which cooperates with the other of the gate-forming projections to retain the tablet in the predispensing chamber when the slidable inner member is in its first position and which is moved away from said other of the gate-forming projections as the slidable inner member is moved to its second position to provide a gap between the tablet-retaining projection and said other of the gate-forming projections, said gap being of sufficient size to enable a tablet held in the predispensing chamber to pass through. The slidable inner member may be a steel strip folded along its length to give a shallow inverted 'V' shape, one end of said strip being held in a housing in the second inner member and the other end being supported on supporting means fixed within the outer casing of the dispenser, said strip extending through an aperture in the slidable inner member. The invention will be illustrated by the following description of one embodiment thereof. The description is given by way of example only and has reference to the accompanying drawings in which:- Figure 1 is a cross-sectional view of a tablet dispenser (taken along the line I-I shown in Figure 2) in which the inner member is in the first position, Figure 2 is a cross-sectional view taken along the line II-II of Figure 1, and Figures 3a to 3d are partial cross-sectional views illustrating the operation of the tablet dispenser. The tablet dispenser comprises an outer casing 1 which comprises a right cylindical side wall 2 and a base 3. The side wall extends beyond the base 3 to form an annular wall 3 a . The base 3 has a dispensing aperture 4 through which tablets are dispensed one at a time. An inner member 5 slides within the casing 1 from a first position shown in Figures 3a and 3c to a second tablet-dispensing position shown in Figures 3b and 3d. The inner slidable member 5 is urged towards its first position by a spring member 6 and comprises a hemi-cylindrical upper wall 8. The outer end is closed by a cap 7. A sloping ramp surface 9 extends inwardly from the base of the upper wall 8 and leads to a chamber 10 defined between a lower central wall 11 of the slidable inner member 5, raised portions 12, 13 extending inwardly from the central wall 11 and a second inner member 14 which is fixed in position within the casing 1. The height of the chamber 10 is such that only a single layer of tablets can be accommodated. A dispensing passageway 15 extends downwardly across the inner face of the central wall 11. The passageway is defined by the projection 13, projection 12a and the central walls of the slidable inner member 5 and the second inner member 14. The distance between the projections 13, 12a is only slightly larger than the diameter of the tablets to be dispensed so that only a single column of abutting tablets can be accommodated in the passageway 15. The slidable inner member 5 has a projection 16 running parallel to a vertical side wall of the projection 13 defining therebetween a channel 17 containing a wedge-shaped projection 18, the scarp face of which faces upwards as shown in Figure 1. Elongate projections 19, 20 extend inwardly into the channel 17 from the central wall of the second inner member 14 and cooperate with the channel to guide the slidable inner member 5 as it moves between its first and second positions. In the first position the scarp face of the wedge shaped projection 18 abuts the elongate projection 19 thus restricting any further movement in an upward direction as shown in Figure 1. A gate-forming projection 21 and a tablet retaining projection 22 also extend inwardly from the second inner member. The projections 19 to 22 are fixed in relation to the casing 1 and the slidable inner member 5 moves relative to them as will be described hereinafter with reference to Figures 3a to 3d as the dispenser is operated. The central wall 11 of the slidable inner member 5 is substantially rectangular and has a downwardly-directed rectangular projection 23 extending from its bottom edge. In the assembled dispenser as shown in Figures 1, 2 and 3, the projection 23 extends into the dispensing aperture 4 on the base 3 and is provided with a second inwardly extending tablet-retaining projection 24. The slidable inner member 5 has a slit-shaped aperture 25 through which the spring member 6 passes. The aperture 25 has a sloping upper surface as is shown in Figure 2 so that the slidable inner member 5 contacts the spring at a sharp edge on the inwardly directed face of the lower central wall 11. The spring member 6 is manufactured from steel and is folded along its length to give the shallow-inverted 'V' shape shown in Figure 1. One end of the spring member 6 is located in a housing 26 integrally moulded with the second inner member 14. The other end of the spring member is supported on supports 27 integrally moulded with the casing 1. As the slidable inner member 5 is moved from one position to another the spring member 6 is deformed in such a way that an audible click is produced. The second inner member 14 is formed with a semi-circular inwardly sloping ramp surface 28 which, together with the ramp surface 9 formed in the slidable inner member 5, forms the base of the reservoir 29 in which the tablets are randomly orientated. Preferably the central edge of the ramp surface 9 is higher than the central edge of th ramp surface 28 by an amount equal to half the diameter of the tablets to be dispensed. The two inwardly sloping ramp surfaces cause tablets to pass from the reservoir 29 into the chamber 10 and then into the dispensing passageway 15. The ramp surface 28 is supported by a web 30 extending from the housing 26 to the underside of the ramp surface 28. In a similar manner the ramp surface 9 is supported by a web 31 extending from the outward facing surface of the central wall 11 to the underside of the ramp surface 9. To prevent movement of the lower central wall 11 away from the second inner member 14, the slidable inner member 5 is provided with an outwardly directed stud 32, the outer end of which contacts the supports 27. The casing and the inner members 5, 14 may conveniently be moulded from a suitable plastics material such as polystyrene. In the embodiment illustrated the dispenser has circular cross-section though it will be evident to those skilled in the art that the cross-section may be of any desired shape. The operation of the tablet dispenser of the present invention will now be described by reference to Figures 3a to 3d. In Figure 3a, is shown the position in which the dispensing channel 15 contains a single column of tablets which are prevented from passing into the pre-dispensing chamber 33, which is defined by the projections 24 and 22 and which at this stage contains no tablet, by the projection 21. As the slidable inner member 5 is urged to slide into the casing 1 to its second position, the dispensing passageway 15 is moved downwardly until the lowermost end of the dispensing passageway 15 is aligned with the gap between the gate-forming projection 21 and the tablet retaining projection 22. The lowermost tablet A then enters this gap as is shown in Figure 3b. As the slidable inner member 5 is returned to its first position (figure 3c) by the spring member 6, the tablet A falls into the pre-dispensing chamber 33 and the tablet B is retained in the dispensing passageway 15 by the projection 21. The gap between the projection 22 and the projection 24 is not sufficient for the tablet A to pass through the dispensing aperture 4. As the slidable inner member 5 is again urged to slide into the casing 1 to the position shown in Figure 3d, the tablet A is urged into the recess 33 above the projection 24 by the projection 22. When the position shown in Figure 3d is reached the tablet A is dispensed through the dispensing aperture 4. As the slidable inner member is moved from its first position shown in Figure 3c to its second position shown in Figure 3d, the tablet B passes into the gap between the projections 21, 22 as described above for tablet A. After the first operation of the dispenser, each subsequent operation will result in the tablet in the pre-dispensing chamber being dispensed as the operator pushes on the cap 7 to urge the slidable inner member to its second position. Each time the dispenser is operated the dispensing passageway 15 and chamber 10 are moved towards the base of the dispenser. The upper part of the elongate projection 19 agitates the tablets in the chamber thus facilitating the arrangement of the tablets in the single layer in the chamber 10 and their subsequent passage into the dispensing passageway 15.

Claims: A dispenser for dispensing tablets one at a time which comprises (a) an outer casing (1) containing a reservoir (29) in which the tablets are randomly orientated, (b) a slidable inner member (5) which slides within the outer casing (1) from a first non-dispensing position to a second tablet-dispensing position and which is urged towards its first position by a spring member (6), (c) means on the slidable inner member (5) for causing tablets to be transferred from the reservoir and to become arranged in a single layer in a chamber (10) which feeds the tablets into a dispensing passageway (15) which is of such a width that only a single column of abutting tablets can be accommodated, (d) tablet-controlling means (21,22) fixed relative to the outer container which retain the lowermost tablet in the dispensing passageway (15) when the slidable inner member is on its first position and which comprise a gate into which said lowermost tablet passes when the slidable inner member (5) is in its second position, characterised in that the dispenser comprises a pre-dispensing chamber (33) in which the lowermost tablet is stored after it has passed into said gate, said tablet entering the pre-dispensing chamber as the slidable inner member (5) moves from the second to the first position and tablet-retaining means (24) which retain said tablet in the predispensing chamber when the slidable inner member (5) is in its first position but permit the tablet to be dispensed when the slidable inner member (5) is in its second position and in that the slidable inner member (5) is provided with a channel (17) running parallel to the direction of movement of the slidable inner member (5), said channel (17) facing a second inner member (14) fixed in position within the outer casing (1), said channel receiving therein elongate projections (19,20) extending from the central wall of the second inner member (14) to guide the slidable inner member (5) as it slides between its first and second positions and the channel is provided on its base with a wedge shaped projection (18), the scarp face of which contacts one of the elongate projections (19) when the slidable inner member (5) is in its first position. A dispenser as claimed in claim 1 wherein the slidable inner member (5) comprises (a) a sloping ramp surface (9) (b) a generally triangular chamber (10) at the lower end of the ramp surface defined between a lower central wall (11) of the slidable inner member, a central wall of the second inner member (14) and projections (12,13) extending from the central wall (11) of the slidable inner member (5) towards the second inner member (14), the separation between the central walls of the two inner members (5,14) being such that only a single layer of tablets can be accommodated in the chamber (10) and (c) a dispensing passageway (15) extending downwardly across the face of the central wall (11) of the slidable inner member (5) leading to the gate, said passageway being defined by said central walls and by projections (12a,13) extending from the central wall (11) of the slidable inner member (5) towards the second inner member (14). A dispenser as claimed in claim 1 wherein one of the elongate projections (19) extends into the chamber (10) to agitate the tablets therein when the slidable inner member (5) is moved between its first and second positions. A dispenser as claimed in any one of the preceding claims wherein the gate is formed between two gate-forming projections (21,22) extending from the central wall of the second inner member (14), the gate-forming projections (21,22) being positioned so that when the slidable inner member (5) is in its first position one of the gate-forming projections (21) at least partially occludes the passageway (15) preventing the egress of the lowermost tablet from the passageway (15) and when the slidable inner member (5) is in its second position the lowermost tablet in the passageway (15) passes into the gap between the gate-forming projections (21,22). A dispenser as claimed in any one of the preceding claims wherein the slidable inner member (5) is provided with a downwardly directed projection (23) which extends into the aperture (4) in the base (3) of the outer casing through which tablets are to be dispensed, said downwardly-directed projection (23) being provided with a tablet-retaining projection (24) which cooperates with the other of the gate-forming projections (22) to retain the tablet in the predispensing chamber when the slidable inner member (5) is in its first position and which is moved away from said other of the gate-forming projections (22) as the slidable inner member (5) is moved to its second position to provide a gap between the tablet-retaining projection (24) and said other of the gate-forming projections (22), said gap being of sufficient size to enable a tablet held in the predispensing chamber to pass through. A dispenser as claimed in claim 1 wherein the spring member is a steel strip folded along its length to give a shallow inverted 'V' shape, one end of said strip being held in a housing (26) in the second inner member (14) and the other end being supported on supporting means (27) fixed within the outer casing of the dispenser, said strip extending through an aperture (25) in the slidable inner member (5).

Inventors: FULLWOOD, RICHARD LESLIE, HALLIDAY, ALFRED WILLIAM
Applicants: THE BOOTS COMPANY PLC
Application year: 1987
Main classification: B65D83
IPC codes: B65D83