This invention relates to a novel device, being an oral inhaler by means of which a volatile material may be inhaled.

Oral inhalers of this general type are known, for example as used by asthma sufferers etc for the inhalation of a medicament as a vapour or as a stream o air-carried particles or droplets. It is desirable that such inhalers are convenient enough to be easily carried, for example in a pocket or handbag etc, for use when needed, that they should be cheap and robust, and that they should be capable of being closed so as to restrict ingress of contamination, or evaporation of volatile contents. One known type of inhale is that described in ES-1007117-U (Calmante Vitaminado S.A.).

The present invention provides an oral inhaler which to some extent at least provides these desirable features in a particularly convenient form of device.

Accordingly this invention provides an oral inhaler comprising;

a box member having two side walls separated by an edge distance less than the length and width dimensions of each side wall, and having at least one edge (hereinafter termed the "front edge") which has at least one inhalation opening therein for inhalation therethrough, the box member having at leas one additional opening for the ingress of air;

said box member being at least partly contained within a substantially conforming casing;

said casing being slideably mounted upon the box member and being capabl of being slid relative to said box member into a first position in which the said openingCs) in the front edge of the box member is/are covered, and into second position in which the opening(s) is/are uncovered;

said box member containing or being capable of containing a volatile materi for inhalation.

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The side walls are suitably substantially parallel and substantially planar, and are suitably generally rectangular in shape. The term "rectangular" used herein includes "square", and also includes shapes which are generally rectangular but have rounded or iamfered corners, but which do not detract from the generally rectangular shape, for example lozenge shapes.

The box member is preferably substantially tetragonal in general shape, although its walls may meet its edges with sharp corners, rounded corners or chamfered corners which themselves may meet the walls and edges with curves. In such a substantially tetragonal box member the front edge, and the opposing edge may for example be profiled though without detracting from the overall generally tetragonal shape,. For example these edges may be curved, so that a cross section through the walls and these edges may be lozenge-shaped.

Suitably the edge distance is substantially less than the length or width dimension of the side walls. Suitably the edge distance may be 0.25 or less, eg 0.2 or less, eg 0.1 or less of the length dimension of the box member. Suitable ratios of side wall length : side wall width : edge distance of the box member are 6-10 : 6-10 : 1. A suitable edge dimension for the box member is around 5 +/- 2 mm.

The front edge may be completely open, or it may comprise an edge wall having one or more orifices therein, of suitable dimensions to allow an easy inhalation of air without undue sucking effort. These openings may suitably total about 20 - 50 mm** ^* * in area. The edge opposing the front edge, and the remaining edges, ie in a substantially tetragonal box member the edges at right angles to the front edge, ie end edges, may be closed, or maybe partly or completely open.

The additional opening for the ingress of air, ie during the inhalation of air through the opening(s) in the front edge may be located in any position in the box member. For example the additional openings may be provided as openings in a rear edge opposing the front edge accross the width of the box

member, or in the side walls, or in the ends. The additional openings may for example be in one or both of the end edges of the box member, which may for example be completely open, however in such an embodiment the conformity of the box member and the casing should not be such as to restrict the flow of ingress air between the box member and the casing.

The substantially conforming casing may also be substantially tetragonal, and may optionally have rounded or chamfered edges and/or corners, eg for safety (ie avoiding sharp corners) or for aesthetic appearence.

Suitably the box member may be completely contained within the casing when the casing is slid into its first position, and partly contained when the casing is slid into its second position. In this way the casing can prevent evaporation of the volatile material and contamination.

The casing is suitably slideably mounted such that it may slide in a direction parallel to the front edge. Slideable mounting may be achieved by the use of a casing which conforms very closely to the box member, so that there is some degree of friction between the box member and the casing, so that when the casing has been slid into the first or second position, or into an intermediate position there is some frictional resistance to sliding. This resistence can help to retain the casing in a desired position on the box member.

The surfaces of the box member, and the casing, eg the walls and edges which slide across each other may be provided with guide means, for exampl to assist smooth sliding and to help prevent jamming for example if the box member and the casing should twist out of alignment during sliding.

Suitably the guide means may comprise interlocking ridges and corresponding grooves on the box member and the casing, running parallel to the direction of sliding. The extent of such interlocking may help in providin the above - mentioned degree of friction between the box member and the casing.

The box member and casing may be provided with end stop means to prevent the casing from being easily removed from the box member, eg to prevent it

falling off. Suitable end stop means may comprise one or more grooves in one or more walls of the box member and or casing, into which one or more cooperating projections on the casing and or box member fit. Such groove(s) may be alligned parallel to the front edge. If such grooves do not run for the entire length of the wall(s) so that the projections) is/are only allowed a limited amount of travel, the end of the groove(s) may function as an end stop means. Conveniently if the groove(s) is/are in the form of slot openings in the wall(s) of the box member, it they may comprise the additional opening(s) for the ingress of air. Other end stop means will be apparent to those skilled in the art, for example projections on the box member which may end stop against corresponding projections on the casing.

The casing may comprise a single casing element slideably mounted on the box member. In its first, covering, position such a single element may butt up against a flange on the box member to provide sealing against evaporation and contamination.

Alternatively the casing may comprise two casing elements slideably mounted on the box member. In their first, covering, position these two elements may butt up against each other or may fasten together, eg in a snap-fit or frictional interlocking, suitably meeting around the mid point of the length of the box member. The two elements may be independently slideable toward opposite ends of the box member, so that in the second, uncovered position the opening(s) in the front edge are located between the two casing elements.

The use of two casing elements in the above-described manner is particularly convenient, as the two casing elements, when in their second position, may be held by the fingers, and may thus form a handle, allowing the user to hold the inhaler in a manner similar to the use of a "mouth organ" or harmonica. This manner of use conveniently avoids the posibility of contamination of the vicinity of the front edge by contact with the hands.

The casing may be made of a size only slightly larger than the box member, so that the entire inhaler may be made in a "credit card" size and shape.

Conveniently the entire box member and casing may be made of plastics materials such as polystyrene, polythene, or polypropylene.

An inhaler of the above-described type has the further advantage that in contrast to many present oral inhalers there is no separate removeable cover for the inhalation openings, which may easily be lost on opening, or suffer contamination if put down somewhere.

The volatile material for inhalation m ay comprise a known material for the easing of various respiratory symptoms, for example menthol. The material may be present as a solid, eg a pellet or encased within an air-permeable container or capsule, or may be a liquid, such as terpenoid oils, which may be impregnated on a wicking material or into a solid matrix.

To assist indroduction of the volatile material into the box member, the latter may be made in an openable form, so that it can be manfactured in an open form, the volatile material inserted, and the box member then closed before insertion into the casing. When the volatile material is in the form of a liquid impregnated into a pad of wicking material, the box member may include internal positioning means to ensure that the pad is securely and correctly located within the box member.

The invention will now be described by way of example only with reference to the following drawings, in which:

Fig. 1 shows an overall perspective view of an inhaler with its casing in the second position.

Fig. 2 shows an overall perspective view of an inhaler with its casing in the first position. Fig. 3 is a sectional view through the inhaler about the line A-A of Fig.

1 looking in the direction of the arrows.

Fig. 4 is a section through the inhaler of Fig. 1 about the line B-B. Fig. 5 shows an overall perspective view of an alternative form of inhaler.

Figs. 6 and 7 show overall perspective views of alternative forms of box member.

Fig 8. shows a part sectional view of an inhaler of the invention incorporating a box member as shown in Fig 7.

Referring to Fig. 1 an inhaler is shown overall. The inhaler comprises a box member (1), having two substantially parallel, planar, substantially rectangular walls (2), and being of generally tetragonal shape. The box member (1) has a front edge (3), in which there are a number of openings (4) in the for of circular holes.

The box member (1) is partly contained within a casing in the form of two casing elements (5A,5B), and the part of the box member (1) which is partly contained is shown in Fig. 1 by dotted lines. Elements (5A,5B) are slideably mounted on box member (1) and are capable of sliding movement in the direction shown by the arrows. The box member (1) has slots (6) in its walls (2) which pass completely through the wall(s) (2), and which are parallel to the front edge (3) but do not run for the entire length of wall (2), teπninating at slot ends (6A). The elements (5A,5B) have pins (7) projecting inwardly and which fit into slots (7). The pins (7) are for clarity shown as projecting through the wall of the elements (5A,5B), but are conveniently integrally moulded with elements (5A,5B). The elements (5A,5B) are thereby permitted to slide into the position shown in Fig. 1, but not to easily be separated from box member (1), by means of the end-stop interaction between pins (7) and slot ends (6A). The slots (6) serve an additional function of forming additional openings for the ingress of air during inhalation through openings (4).

Referring to Fig. 2, the inhaler of Fig. 1 is shown with the casing (5) in its first, covering, position, in which elements (5A,5B) have been slid together to meet at approximately the mid point of the length of walls (2), and to cover openings (4). The casing (5) substantially conforms in size and shape to the box member (1), and is of generally tetragonal shape but having rounded corners. The box member (1) contained within the casing (5) is shown with dotted lines in Fig. 2.

Referring to Fig. 3, the close conformity of shape and size of the casing (5 A) to the contained box member (1) is shown. The pins (7) are shown as integral with the casing (5A). Within box member (1) is shown a pellet of a volatile solid material, being a medicament (8). The front edge (3) is curved, giving a lozenge-shaped cross section to the box member.

Referring to Fig. 4, an end edge (9A) of the box member is shown as open, and an alternative arrangement in which an end edge (9B) is closed is also shown. Elements (5A,5B) are shown as being provided with interlockable portions (10A,10B) of a generally known type.

Referring to Fig.5, an alternative form of inhaler is shown, having a box member (1), walls (2), a front edge (3), openings (4) and slot(s) (6) corresponding in form and function to that shown in Fig. 1. The inhaler is provided with only one casing member (5C), having pins (7), and corresponding in form and function to (5B) shown in Fig. 1.

One end (11) of box member (1) is closed and is formed into an integral flange (12), against which end (13) of casing element can butt when the element is in its first, covering, position. Flange (12) and end (13) may be provided with interlocking portions (not shown) similar to those (10A,10B) shown in Fig. 4.

Referring to Fig 6, an alternative form of box member (1) overall is shown, having one of its walls (2A) hinged by a film hinge (14) to an end edge wall (15). The wall (2A) is also provided with a clip (15) capable of engaging in a snap-fit with a corresponding slot (16) in end edge wall (17) to enable the box member (1) to be closed. The box member (1) has a front edge wall (3) having inhalation openings (4) therein, and a rear edge wall (18) having openings (19) therein for the ingress of air. The front and rear edge walls (3, 18) are formed on closing the box member (1) about the hinge (14) by part edge walls (3A, 3B, 18A, 18B) on walls ((2A, 2B). On wall (2B) are positioning projections (20) which enable correct and secure positioning of a pad (21) of a wicking material impregnated with a volatile material for inhalation.

Referring to Fig 7, another alternative form of box member (1) overall is shown. As will be apparent the general construction of this box member is similar to that shown in Fig 6, and common features are numbered correspondingly.

Li wall (2B) of box member (1) is formed a socket (22), of generally castellated shape. Socket (22) is positioned and shaped so as to engage with aperture (23) in pad (21) when pad (21) is inserted into box member (1) and thereby retain pad (21) in place. Socket (22) is also provided with teeth (22A) on the free ends of its castellations, which are capable of engaging with a corresponding lip (24A) on a plug (24) which may be inserted through aperture (25) in wall (2A) when box member (1) is folded closed about hinge (14), so as to assist in holding box member (1) closed.

When the box member (1) is folded closed about hinge (14), end walls (17) are formed by the coming together of part end walls (17A, 17B, 17C, 17D). Part end walls (17A and 17B) are held together when the box member (1) is closed by interlocking catch members (26A, 26B).

At each end of the part edge walls (3 A, 18 A) are end stop members (27) each in the form of a resilient tongue (27A) having at its free end a tooth (27B). In the side wall of casing member (5A) is a corresponding tooth (28). Teeth (27B) are so positioned and shaped so that as the closed box member (1) is inserted into casing (5A) it can ride over corresponding tooth (28) in the side wall of casing (5A), but on attempted removal of closed box member (1) from casing (5) teeth (27B) and (28) engage so as to prevent removal of box member (1) from casing (5A).

Referring to Fig. 8, a partial cross sectional view through an inhaler incorporating the box member illustrated in Fig 7 is shown. The plug (24) has engaged with the socket (22). Edge wall (3) has been formed by engagement of part edge walls (3 A, 3B) on closing of the box member (1). The profile of the edge wall (3) includes projecting ridges (29) which engage with corresponding grooves (30) in the edge walls of the casing element (5A).

The method of use of all of the inhalers described above is similar. In use the inhaler is normally supplied to the user with the casing elements (5A,5B,5C) in the first, covering, position, for example as shown in Fig. 2. The elements (5A,5B,5C) may then be slid by hand action in the directions shown by the arrows in Figs. 1 and 5 into the second, uncovered, position, eg as shown in Fig. 1, further sliding of the elements (5A,5B,5C) being prevented by the end stopping of the pins (7) against slot ends (6A), or of teeth (27B) against teeth (28). The user may then hold the inhaler in the manner of a mouth organ to inhale air laden with the vapour of volatile material by sucking through openings (4). After use the elements (5A,5B,5C) may be slid in the reverse direction into the first, covering position, eg as shown in Fig. 2 to prevent contamination and evaporation of the volatile material.