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Patent Searching and Data


Title:
DISPENSER
Document Type and Number:
WIPO Patent Application WO/1994/019252
Kind Code:
A1
Abstract:
A dispenser for viscous extrudable fluids comprising a casing (1) for a collapsible container (3) of the fluid; a roller (7) located within the casing (1) capable of travel along the casing (1) and of causing collapse of the collapsible container (3); and one or more sliders (12, 13) which cooperate with the roller (7) in a one-way action by the intermeshing cooperation of resilient tongues (14) on respectively the slider(s) (12, 13) or the roller (7) so that the roller (7) preferentially moves in the dispensing direction.

Inventors:
HALM HANS (DE)
Application Number:
PCT/EP1994/000437
Publication Date:
September 01, 1994
Filing Date:
February 15, 1994
Export Citation:
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Assignee:
LINGNER & FISCHER GMBH (DE)
HALM HANS (DE)
International Classes:
B65D35/28; (IPC1-7): B65D35/28
Foreign References:
US2261877A1941-11-04
US4575375A1986-03-11
US2712400A1955-07-05
US3780911A1973-12-25
US1695599A1928-12-18
AU9116682B
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Claims:
Claims:
1. A dispenser for viscous extrudable fluids comprising a casing to support in a dispensing position a collapsible container containing a viscous extrudable fluid open at a dispensing end and closed at the other end; a roller located within the casing capable of longitudinal travel along at least part of the length of the casing and of causing compressive collapse of the collapsible container in the course of this travel toward the dispensing end; and one or more sliders slideably mounted on the wall of the casing, the slider(s) being adapted to cooperate with the roller and thereby urge the roller into travel, the urging cooperation between the roller and the slider(s) being by the intermeshing cooperation when the slider(s) move(s) in the dispensing direction of resilient tongues on, or portions connected by resilient tongues to, the roller or the slider(s) with cooperating portions on respectively the slider(s) or the roller, said resilient tongues being adapted to fold when the slider(s) move(s) in the reverse direction to the dispensing direction so that said intermeshing urging cooperation is completely or substantially reduced.
2. A dispenser according to claim 1, wherein the resilient tongues are on the slider(s) rather than on the roller.
3. A dispenser according to claim 1 or 2 wherein the cooperating portions on the roller are teeth on the roller.
4. A dispenser according to claim 1 or 2 wherein resilent tongues on the slider(s) intermesh directly with teeth on the roller, and the tongues are such that when the slider move in the dispensing direction said tongues intermeshingly cooperate with the teeth on the roller so as to urge the roller to travel in the dispensing direction, and such that when the slider slides in the reverse direction the tongues fold on contact with the teeth on the roller to reduce partly or completely the urging cooperation between the tongues on the slider and the teeth on the roller.
5. A dispenser according to claim 4 wherein the tongues are angled in the dispensing direction so that there is an angle of less than 90° between the side of the tongue facing the dispensing direction and the slider.
6. A dispenser according to claim 1, 2 or 3 wherein the slider comprises parallel first and second longitudinal strips connected together by resilient tongues, a first strip having teeth thereon, said teeth being adapted such that when the slider slides in the dispensing direction said teeth intermeshingly cooperate with teeth on the roller so as to urge the roller to travel in the dispensing direction, and such that when the slider slides in the reverse direction the tongues fold on contact of the teeth on the slider with those on the roller to reduce partly or completely the urging cooperation between the teeth on the roller and the teeth on the first strip.
7. A dispenser according to claim 6 wherein the tongues are angled in the dispensing direction so that there is an angle of more than 90° between the side of the tongue facing the dispensing direction and the longitudinal direction of the first strip.
8. A dispenser according to any one of the preceding claims wherein the roller is capable of rolling travel along the casing in the dispensing direction.
9. 9! A dispenser according to any one of the preceding claims being openable to enable a tube to be inserted therein, and removed and replaced when empty.
10. A dispenser according to any one of the preceding claims wherein the dispenser is provided with two sliders in parallel.
11. A dispenser according to any one of the preceding claims wherein at least part of the slider, or part of the second strip, or a handle thereon which may be integral with the strip or attached to the strip, extends through the wall of the of the casing so as to allow the slider to be operated by hand action whilst the casing is being held in the hand, or wherein a handle is provided which is pivoted about a fulcrum on the casing and arranged to cooperate with the slider so that application of force to the handle operates the slider via a lever action of the handle.
12. A dispenser according to any one of the preceding claims wherein the casing is provided with a closure which is interconnected with the slider(s) so that movement of the slider(s) causes the closure to move to unseal the open end of the tube, and a subsequent movement of the slider(s) causes the closure to reseal the open end, or alternatively the interconnection of the slider(s) and closure are arranged that operation of the closure to unseal the open end of the tube causes movement of the slider(s) in the dispensing direction, and vice versa.
13. A dispenser according to any one of the preceding claims wherein the cooperation between the slider(s) and the roller has a geared relationship.
14. A dispenser according to any one of the preceding claims wherein there is located on one wall of the casing, preferably in the same wall as the slider(s) at least one longitudinal third strip, connected to the wall of the casing by resilient tongues angled in the dispensing direction such that there is an angle of more than 90° between the side of the tongues facing in the dispensing direction and the wall of the casing, the third strip having teeth thereon adapted to cooperate with the teeth on the roller.
15. A dispenser according to any one of the preceding claims, substantially as hereinbefore described, with reference to the accompanying drawings.
16. A method of making a dispenser for tubes of viscous extrudable fluids, comprising the step of making a dispenser according to any one of the preceding claims.
17. A method of dispensing a viscous extrudable fluid, comprising the step of using a dispenser according to any one of claims 1 to 16.
Description:
Dispenser.

This invention relates to a dispenser for viscous extrudable fluids contained in collapsible containers. Various viscous extrudable fluids are supplied contained in collapsible containers, such as collapsible tubes, from which they can be dispensed by squeezing through a nozzle at one end ("the dispensing end"), the other end being closed. Examples of such fluids are toothpastes, creams, ointments, adhesives, food products, paints, sealing materials, modelling materials, fillers etc. Although such fluids are usually extruded simply by squeezing the tube by hand, dispensers are known whereby the tube can be squeezed by mechanical action, eg. by pinching the closed end of the tube between rollers that progress along the length of the tube. Such dispensers are generally provided for the purpose of hygiene, more accurate metering of the quantity of fluid extruded or simply for aesthetic reasons. Dispensers of this type are for example disclosed in GB 2088818A, GB

602639, GB 461299, GB 1202703, AU 9166/82, US 4575375, 4226336, 4331265, US 4019655, DE 3610268A and DE 2340073A.

According to this invention a dispenser for viscous extrudable fluids comprises a casing to support in a dispensing position a collapsible container containing a viscous extrudable fluid open at a dispensing end and closed at the other end; a roller located within the casing capable of longitudinal travel along at least part of the length of the casing and capable of causing compressive collapse of the collapsible container in the course of this travel toward the dispensing end; and one or more sliders slideably mounted on the wall of the casing, the slider(s) being adapted to cooperate with the roller and thereby urge the roller into travel, the urging cooperation between the roller and the slider(s) being by the intermeshing cooperation when the slider(s) move(s) in the dispensing direction of resilient tongues on, or portions connected by resilient tongues to, the roller or the slider(s) with cooperating portions on respectively the slider(s) or the roller, said resilient tongues being adapted to fold when the slider(s) move(s) in the reverse direction to the dispensing direction so that said intermeshing urging cooperation is completely or substantially reduced. The term "fluid" used herein refers to fluids of any viscosity between mobile liquids and this packs, for example toothpastes, including viscous toothpastes of the conventional type, and the newer so called "liquid toothpastes". The term "collapsible container" includes containers of all types which can collapse under compressive pressure to extrude their contents, but particularly includes collapsible tubes such as those from which toothpastes, ointments, creams, cosmetic products are commonly dispersed from.

Preferably the resilient tongues are on the slider(s) rather than on the roller.

Suitably the cooperating portions on the roller are cooperating teeth on the roller.

In one embodiment of this dispenser resilient tongues on the slider(s) intermesh directly with teeth on the roller, and the tongues are such that when the slider moves in the dispensing direction said tongues intermeshingly cooperate with the teeth on the roller so as to urge the roller to travel in the dispensing direction, and such that when the slider slides in the reverse direction the tongues fold on contact with the teeth on the roller to reduce partly or completely the urging cooperation between the tongues on the slider and the teeth on the roller.

In this embodiment the tongues are preferably angled in the dispensing direction so that there is an angle of less than 90° between the side of the tongue facing the dispensing direction and the slider.

In a second embodiment of this dispenser the slider comprises parallel first and second longitudinal strips connected together by resilient tongues, a first strip having teeth thereon, said teeth being adapted such that when the slider slides in the dispensing direction said teeth intermeshingly cooperate with teeth on the roller so as to urge the roller to travel in the dispensing direction, and such that when the slider slides in the reverse direction the tongues fold on contact of the teeth on the slider with those on the roller to reduce partly or completely the urging cooperation between the teeth on the roller and the teeth on the first strip. In this second embodiment the tongues are preferably angled in the dispensing direction so that there is an angle of more than 90° between the side of the tongue facing the dispensing direction and the longitudinal direction of the first strip.

In the dispenser of this invention the folding of the resilient tongues reduces the ability of the slider to urge the roller to travel, ideally completely or to a practical minimum, so that an overall one-way non-return action on reciprocal sliding of the slider is provided, by which the roller is caused to travel in the dispensing direction within the casing. Although as a result of inefficiency some travel of the roller in the reverse direction to the dispensing direction may occur the overall movement of the roller will be in the dispensing direction, causing the collapsible container to be progressively pinched between the roller and the wall of the casing resulting in collapse of the tube and extrusion of its fluid contents.

The casing is preferably openable to enable a collapsible container to be inserted therein, and removed and replaced when empty. For example the casing casing may be made in two hinged shells which can be held closed by for example a snap-fit or clasp.

The casing may also have attached thereto or integral therewith a compartment for storage of accessories, for example to store a toothbrush in the case of a dispenser for toothpaste or applicators for adhesives etc. The casing may also have a nozzle at the dispensing end arranged to direct the flow of fluid extruded from

the open end of the collapsible container and/or a removeable closure.

The roller may be of any shape which allows it to travel along the casing in the dispensing direction. The roller may simply slide along inside the casing, e.g. having a generally wedge-shaped face towards the dispensing end, but is preferably capable of rolling travel, e.g. being of circular section, and the co-operating portions on the roller are suitably circumferential teeth.

The roller is preferably cylindrical, but other alternative shapes may be used. Preferred alternative shapes include spherical, oblate spherical or ellipsoidal. Other alternative shapes include bi-conical, with the cones joined at their bases or apexes. Other modifications of these shapes, or further alternatives will be apparent to those skilled in the art

Whatever shape the roller is, the cross section of the casing should be adapted to the shape of the roller so that there is a minimum of cross sectional clearance between the walls of the casing and the roller so that the collapsible container is pinched to the maximum practical extent between the roller and the walls of the casing to ensure efficient extrusion of the contents. For example a square or rectangular cross sectioned casing is suitable for a cylindrical roller, and a circular or "U" sectioned casing is suitable for a spherical roller. The roller may have projecting axles which cooperate with guides, eg. grooves, in the walls of the casing and this is particularly desirable in the case of a spherical roller.

The teeth on a circular section roller may occupy the whole circumferential surface of the roller, or a portion thereof. Alternatively the teeth may be circumferentially located on an axle of the roller. To assist the non-return action the teeth on the roller are preferably asymmetrically edged, the edge cooperating with the tongues or with the teeth on the first strip when the slider slides in the dispensing direction forming a steeper angle with the circumference of the roller than the other edge.

For the same reason the teeth on the first strip on the preferred embodiment are also preferably asymmetrically edged, the edge facing the dispensing direction forming a steeper angle with the strip than the edge facing the reverse direction. The slider may occupy a substantial part of the width of the casing. Alternatively the dispenser may be provided with two sliders in parallel, for example joined by a bridge, their tongues cooperating with teeth on the roller occupying the entire surface of the roller or alternatively on portions thereof corresponding with the two sliders. These two arrangements are advantageous in steering the roller in its .travel along the casing, so as to prevent sideways movement of the roller and consequent jamming.

The slider may be operated in various ways. In one embodiment at least part of the slider, or in the preferred embodiment part of the second strip, or a handle

thereon which may be integral with the strip or attached to the strip, extends through the wall of the of the casing eg. via a slot or hole so as to allow the slider to be operated by hand action, eg. by the thumb or a finger whilst the casing is being held in the hand. In another embodiment a handle may be provided which is pivoted about a fulcrum on the casing and arranged to cooperate with the slider so that application of force to the handle operates the slider via a lever action of the handle. Such arrangements allow convenient single hand operation.

The casing may be provided with a closure, eg. a cap or plug arranged to seal the open end of the collapsible container when dispensing of the fluid is not required, and this closure may be interconnected with the slider(s) so that movement of the slider(s), particularly in the dispensing direction, causes the closure to move to unseal the open end of the container, and a subsequent movement of the slider(s), particularly in the reverse direction, causes the closure to reseal the open end. Alternatively the interconnection of the slider(s) and closure may be arranged that operation of the closure to unseal the open end of the container causes movement of the slider(s) in the dispensing direction, and vice versa.

Conveniently when a handle is provided for operation of the slider whether by a lever action or otherwise, the closure may also be arranged to be operated to the handle, for example by being cooperatingly connected to the handle. Additionally or alternatively the closure may be mounted on the handle or the casing in such a position that the closure may be independently operated by hand action as the handle is operated, either simultaneously with the operation of the handle, or preferably immediately before the handle is operated to minimise the possibility of extrusion of the contents of the collapsible container commencing before the closure is opened. In all embodiments when a closure is provided which is interconnected with the slider(s) it is desirable that the slider(s) cannot be operated independently of the closure, so that compression of a tube sealed by the closure cannot occur.

The cooperation between the slider(s) and the roller may have a geared relationship, so that by selecting the relative size of the teeth on the roller and the teeth on the first strip a convenient movement of the slider(s) may result in extrusion of a desired amount of the fluid. For example about 1 to 3, eg, 2 cm of movement of a slider resulting in extrusion of a typical dose of toothpaste from a tube thereof may be convenient in a dispenser intended to be held in one hand and operated by the thumb of the same hand. The geared relationship facilitates metered extrusion of fluids, for example by incorporating a metering scale on the slider(s) and/or the wall of the casing. Metering may be useful in for example the extrusion of two part adhesives where one part is the adhesive and the other is a hardening catalyst, and extrusion of a relatively precise quantity of each is important for achieving or controlling hardening.

Methods of slideably mounting the slider(s) on the wall of the casing will be apparent to skilled in the art, for example the wall of the casing may have one or more longitudinal grooves into which a corresponding portion of the slider(s) slideably fits. To improve the non-return action in the preferred embodiment there may be located on one wall of the casing, preferably in the same wall as the slider(s) at least one longitudinal third strip, connected to the wall of the casing by resilient tongues angled in the dispensing direction such that there is an angle of more than 90° between the side of the tongues facing in the dispensing direction and the wall of the casing, the third strip having teeth thereon adapted to cooperate with the teeth on the roller. The teeth on the strip are preferably asymmetrically edged, the edge facing the dispensing direction forming a steeper angle with the strip than the edge facing in the reverse direction. The shape of this longitudinal third strip, its tongue and teeth, may be the same as, or substantially the same as, those on the first strip of the slider(s). The dispenser is preferably made of plastics materials, which lend themselves to manufacture of the dispenser in an aesthetic design and colour, for example in the case of a toothpaste dispenser matching bathroom accessories such as toothbrush, soap dish etc. in a coordinated set

The invention also provides a method of making a dispenser for tubes of viscous extrudable fluids, comprising the step of making a dispenser as described above.

The invention also provides a method of dispensing a viscous extrudable fluid, which involves the use of a dispenser as described above.

The invention will now be described by way of example only with reference to the following figures.

Fig 1 shows longitudinal and cross sectional views of a dispenser having a cylindrical roller.

Fig 2 shows longitudinal and cross sectional views of a dispenser having a spherical roller, and a suitable roller. Fig 3 shows in longitudinal section the general operation of the dispenser of

Figs 1 and 2.

Fig 4 shows a cross section through the dispenser of Fig 1 when provided with further toothed strip.

Fig 5 shows the single handed operation of the dispenser of Fig 1. Fig 6 shows two types of openable casing.

Fig 7 shows in longitudinal section a dispenser provided with a handle for operation of the slider, and having a closure.

Fig 8 shows part of a dispenser in which resilient tongues on the slider intermesh directly with teeth on the roller.

Referring to Fig 1 and 1A, a dispenser having a casing of rectangular cross section is shown in longitudinal part sectional view in Fig 1, and in cross section about the line A- A of Fig 1 in Fig 1 A. The casing is openable being made in two parts closed by a snap-fit join (2). The casing (1) supports a toothpaste tube (3) having an open dispensing end (4) projecting through an opening (5) in the dispensing end of the casing (1). The casing has a removeable closure (6) covering the dispensing end (4) of the tube (3).

Within casing (1) is located a cylindrical roller (7) having circumferential teeth (8) and a short axle (9) resting in a guiding ledge (10) in the walls of the casing (1). The teeth (8) are asymmetrical, having one edge (8a) meeting the circumference of the roller (8) almost tangentially and the other edge (8b) meeting the circumference almost radially.

In one wall (la) of the casing (1) is a grooved longitudinal moulding (11) in which is slideably fitted a slider consisting of a longitudinal second strip (12), connected to a first strip (13) by resilient tongues (14) angled in the dispensing direction. The side of the tongues (14) facing in the dispensing direction (shown by an arrow in Fig 1) forms an angle of greater than 90° with the longitudinal direction of the first strip (13). On the face of first strip (13) are teeth (15) which are asymmetrical, the face (15a) facing the dispensing direction meeting the strip (13) at about 90° and the face (15b) facing the reverse direction meeting the strip at a less steep angle.

At the end of the strip (12) nearest to the dispensing end of the casing (1) is provided a push button (16) extending through a slot (17) in the wall (la) of the casing (1) by means of which the slider (12, 13, 14, 15) may be operated. Referring to Fig 2, a dispenser having a casing of "U" shaped cross section

(18) is shown in longitudinal part sectional view in Fig 2a, and in cross section about the line B-B in Fig (2b). The casing (18) is again openable being made in two parts closed by a snap-fit join (19), and has a removeable closure (20) covering the dispensing end of a contained tube (not shown). The "U" shaped casing (18) is of a cross section adapted to contain a spherical roller (21) shown end-on in Fig 2A and sideways as in Fig 2B. The roller (21) has circumferential teeth (22) that are asymmetrically shaped, one edge (22a) meeting the circumference almost radially, and the other edge (22b) meeting the circumference almost tangentially. The roller (21) is provided with a short axle (23), and when the roller is in place within the casing (18) the ends of the axle rest in the guiding grooves (24) in opposite walls of the casing (18).

In one wall (18a) of the casing is a moulding (25) having a longitudinal slot (26) into which slots a slider consisting of a longitudinal strip (27) connected to a strip (28) by longitudinal tongues (29) angled in the dispensing direction. On the face

of the strip (28) are teeth (30, not all shown) which are asymmetrically shaped identically to the teeth (15) of Fig 1.

The strip (27) is formed into a "T" section, of which the upper bar of the "T" (31) is moulded into a push button (32) near the dispensing end of the dispenser. The bar (31) and consequently the button (32) extend through the wall (18a) of the casing (18) via the slot (26) and form a handle portion by means of which the slider may be operated.

Referring to Fig 3 the general mode of operation of the dispenser of Figs 1 and 2 is shown. As shown in Fig 3 A, as the strip (13, 28) is moved in the dispensing direction (shown by arrow), the teeth (15, 30) intermesh with teeth (8, 22) on the roller (9, 21) causing collapse of the pinched portion (3a) of the tube and extrusion of the contents of the tube, (not shown). As shown in Fig 3B, as the strip (13, 28) is moved in the reverse direction to the dispensing direction (shown by aιτow), when teeth (15, 30) contact the teeth (8, 22) on the roller, the tongues (14, 29) fold so that the teeth (15, 30) and (8, 22) do not intermesh and the roller (9, 21) is not urged in the reverse direction, thereby leaving collapsed tube (3b) rearward of the roller. Friction between the roller (8,21) or its axle (23) and the side wall of the casing (1,18), also serves to hinder the roller (8,21) from rolling in the reverse direction to the dispensing direction. This procedure may be repeated in a reciprocating action of the strip (13,28) to extrude a desired quantity of the tube contents.

Referring to Fig 4A, a cross sectional view of a casing (32) is shown, on a wall (32a) of which are located two sets of grooved longitudinal mouldings (33) in which are slideably fitted two respective longitudinal second strips (34) connected by resilient tongues (35) to toothed first strips (36). Mouldings (33), strips (34) and (36) and tongues (35) are identical to mouldings (11), strips (12) and (13) and tongues (14). Between mouldings (33) is mounted a toothed third strip (37) of identical construction to first strips (36) and connected to the wall (32a) by resilient tongues

(35) which are angled in the dispensing direction. Figs 4B and 4C show respectively sections about lines B-B and C-C along part of the length of strip (36) and (37) viewed from the direction of the arrow, showing the identical shape of toothed strips

(36) and (37) and the angling of the resilient spines (35), (38) in the dispensing direction shown by the arrow in Figs 4B and 4C.

Referring to Fig 5, the single handed operation of the dispenser of Fig 1 is shown, in which the push button (16) of the dispenser of Fig 1 is being reciprocally moved by the thumb (39), to cause an overall movement of the roller (9) in the dispensing direction to cause extrusion of the toothpaste contents (40).

Referring to Fig 6A and 6B, two methods of making the casing openable are shown, the casing (1), (18) is shown made in two shells joined by a hinge (41), (42) respectively at the reverse end to the dispensing end and longitudinally, so that the

casing (1), (18) may be opened and a replacement tube inserted.

Referring to Figs 7 A, 7B and 7C, a dispenser is shown having a casing (1), a roller (9) and a slider in the form of a first strip (13) having teeth (15), connected to a second strip (12) by resilient tongues (14) in an arrangement identical to that of Figs 1-6. The second strip is slideably mounted in a wall of the casing (1) by means not shown. The casing contains a toothpaste tube (3), having a nozzle (4) projecting from the dispensing end of the dispenser. The rearward end (3b) of the tube has been compressed by the roller (9).

Near the dispensing end of the dispenser is a handle (41), pivotally mounted in the walls (not shown) of the casing (1) by an axle (42) forming a fulcrum. Part (41a) of the handle (41) extends outside the casing (1) through an aperture (43). Another part (41b) of the handle (41) is pivotally connected to the second strip (12) by a pivot (44) passing through a corresponding hole (not shown) in the second strip (12).

A closure (45) is pivotally mounted on the handle (41) and seals the nozzle (4) of the tube (3). The closure (45) has a handle portion (45a). Referring to Fig 7B, by thumb action applied to the handle portion (44a) the closure (44) has been caused to pivot in the direction of the arrow and unseal the nozzle (4).

Referring to Fig 7C, further thumb action has been applied to the part (41a) of the handle (41) extending outside the casing (1). This has caused the handle (41) to pivot about the pivot (42), moving in the direction of the arrows. This movement has caused the slider (12, 13, 14, 15) to move in the dispensing direction, causing the roller (9) to roll in the direction of the arrow, to further compress the tube (3), and extrude toothpaste (46) from the nozzle (4).

On pivoting the handle (41) in the reverse direction to that of the arrows, the handle may be returned to the position shown in Fig 7B, causing the slider (12, 13, 14, 15) to move in the reverse direction to the dispensing direction, and the tongues (14) to fold as explained above so that the teeth (15) do not intermesh with those (not shown) on the roller (9). This procedure may then be repeated by a rocking motion of the handle (41) about pivot (42) so that a reciprocal movement of the slider (12, 13, 14, 15) occurs and a desired amount of toothpaste (46) can be extruded, subsequent to which the closure (45) may be returned to the position shown in Fig 7A thereby sealing the nozzle (4).

Referring to Fig 8, part of the mechanism of a dispenser is shown having a slider (81), from which project resilient tongues (82) angled in the dispensing direction indicated by the arrow in Fig 8A, and a roller (83) having circumferential teeth (84) thereon. Only those teeth 84 in the vicinity of slider (81) are shown for convenience. The teeth 84 are asymmetrical, having one edge (84a) meeting the circumference of the roller (82) at a steeper angle than the other (82b).

When the slider is moved in the dispensing direction indicated by the arrow in

Fig 8A, the tongues (82) intermeshingly cooperate with the teeth (84), one part (82a) of the tongues (82) being shaped so as to enhance the cooperation. The roller (81) is consequently urged to rotate and roll in the direction of the arrow in Fig 8A.

When the slider is moved in the reverse direction to the dispensing direction, i.e. in the direction indicated by the arrow in Fig 8B, the tongues (82) fold as shown (82b) out of intermeshing cooperation with the teeth (84), and the roller does not rotate.