Media Dispenser for Dispensing a Dosed Medium in a Gas Flow

The invention relates to a discharge apparatus for media, which is suitable for a single medium and a separately stored, identical or non-identical, flowable media, optionally having a different aggregate state, in which the medium is preferably at least partly liquid pulverulent as powdery. Appropriately, the discharge apparatus is constructed in such a way that the medium is fed or torn out of one or more medium chambers with a gas flow. The medium chamber can be formed by a medium reservoir.

Such dispensers are known as inhalers for pulverulent substances. In the latter, a powder-containing capsule is opened by destruction, and its content is sucked in with the respiratory air of the inhaling person.

Discharge apparatuses are also known in which liquid or pulverulent substances are atomized, dispersed and mixed by means of a compressed gas flow for producing an aerosol. However, the discharge apparatus must be connected to an external compressed gas source, which greatly restricts the usability thereof.

European patent application 309 010 also discloses a discharge apparatus combined with an air pump which has proved very satisfactory. However, the medium with the compressed air flow is not fed out of a chamber, and instead, the compressed air flow is merely supplied separately to a discharge nozzle, where mixing takes place; i.e., initially the medium is conveyed independently of the air flow and via a separate pump to the discharge nozzle.

An object of the invention is to provide a dispenser of the aforementioned type, which avoids the disadvantages of known constructions. Another object is to independently of external compressed gas sources ensure an effective delivery of the medium from a reservoir-like medium chamber. Further objects will be apparent from the effects and advantages described.

According to the invention, the dispenser has a manually operable device for producing the compressed gas, which can be at least partly supplied to a zone, where it receives an initially stationary medium, picks it up and then delivers it to the outside. Thus, the discharge apparatus can be used at any time; can have a very compact construction, and permits an aerosol-like discharge of varied substances with different aggregate states, particularly pharmaceutical, cosmetic and similar substances.

Appropriately, the apparatus either has an injector directed against or along a storage device for the medium or a turbulent channel, in whose vicinity it is possible to achieve, by cross-sectional constriction, relatively high gas flow turbulences and flow rates, so that the medium is picked up in very finely divided, mixed form. A compressed gas opening can be directed roughly counter to the flow direction out of said region or the medium can be supplied solely as a result of its flow characteristics via grid-like transverse channels to the area of the gas flow and can be received by the latter through vacuum in the transverse channels.

Advantageously, a dosing mechanism is provided for the medium, so that as a function of the manual actuation, only a specific medium quantity is delivered and discharged. Appropriately, the dosing mechanism is directly connected to a medium reservoir via a flow section and, apart from weight action, can also be fed into a dosing chamber in that a limited vacuum is produced in the corresponding area by the gas flow. After filling, the dosing chamber can be closed at the inlet side as a function of the operating path of the dosing mechanism, while no valve is required between the dosing chamber or medium storage device and the discharge opening leading into the open or into a mouthpiece.

As a result of the inventive construction, only a single pump is required, namely that for producing compressed air. It is also possible for several pumps, reservoirs, dosing mechanisms, injectors and associated means defined in the claims to be connected in series or in parallel.

Although other actuating movements are conceivable, the discharge apparatus is appropriately exclusively operated by a roughly linear stroke movement, and its outer end faces remote from one another can be formed by two telescopically interengaging components form the handle. One of the components can form an at least partly exposed medium reservoir, refillable by means of a closable opening, and which carries a pump piston, which engages in the other component, which defines the pump chamber. Both components are fixed to one another in simple manner by snap connections, so that a very simple construction is obtained.

These and other features can be gathered from the claims, description and drawings and the individual features, either singly or in random subcombinations, can be realized in an embodiment of the invention and in other fields and can represent advantageous, independently protectable constructions, for which protection is hereby claimed. Two embodiments of the invention are described hereinafter relative to the drawings, wherein show:

FIG. 1 An inventive discharge apparatus in axial section.

FIG. 2 Another embodiment in a representation corresponding to FIG. 1.

The discharge apparatus 1 only comprises two prefabricated subassemblies 2, 3 assembled by a plug connection and has a medium reservoir 4 from which is discharged during each actuating stroke a partial quantity. Another subassembly 2 forms with its outer casing or jacket 5 the external boundary of the medium reservoir 4 and the associated longitudinal portion of the discharge apparatus. A hollow body is formed by the jacket 5 with a one-piece, circular disk-like end wall 6 at one end and a substantially completely countersunk cover 7 at the other. An eccentric filling opening 8 for the medium reservoir 4, to be closed with a stopper, is provided in the snapped-in cover 5. The two subassemblies 2, 3 form the two components of a pump 9 displaceably mounted against one another by means of a pump stroke, and its pump chamber 10 is bounded by the facing ends of the two subassemblies 2 and 3 and the outer jacket 11 of the subassembly 3, into whose open end is inserted the subassembly 2. The medium reservoir 4 and pump chamber 10 are cross-sectionally circular, the internal cross-section and the external width or diameter of the pump chamber 10 being larger than that of the medium chamber 4. The jacket 11 is constructed in one piece with an end wall 12 forming the other end of the discharge apparatus 1 and receives, as the piston path, a circular pump piston 13 facing the same and which is mounted on the subassembly 2 and is directly adjacent to the end wall 6.

The two subassemblies 2, 3 are fixed against one another axially and to prevent rotation by at least one snap connection 14. Each snap connection 14 has, on the outer circumference of the jacket 5, a projecting snap cam, and for its engagement in the jacket or casing 11, an axial slot, the piston path being connected up to the end wall 12 to the axial slots. The cup-shaped pump piston 13, whose edge forms a sealing lip and which is also fixed by means of a snap connection 15, is provided radially outside its snap fastening in the bottom with at least one gas intake 16 for the pump chamber 10, which can draw in by means of the axial slots and which is provided with a not shown, spring-free check valve. Within the snap connection 15 in the bottom of the pump piston 13, at least one gas outlet 17 is provided passing through the same and by means of which, during the pump stroke, the air from the pump chamber 10 is forced downwards into a circular flow channel 18. The latter is bounded by a channel jacket 19 located within the medium reservoir 4 and bounding the inner circumference thereof and which passes through the end wall 6, and at its associated end fixes the pump piston 16 to the snap connection 15. Substantially all the aforementioned components are located in a central axis 20 of the discharge apparatus 1.

Within the flow channel 18 in contact-free manner a narrower outlet channel 21 is provided, which is bounded by two channel parts 22, 23 which are telescopically axially displaceable against one another with the subassemblies 2, 3. A channel part 22, which bounds on the inner circumference the circular flow channel 18, is fixed by one end radially within the gas outlet 17 in a central opening of the pump piston 13, and in the same way as the channel jacket 19, projects from the pump piston or the end wall 6 freely into the medium reservoir 4. The other channel part 23 guided with a sealing lip on the inner circumference of the channel part 22 is fixed by its corresponding end, and a snap connection to the end wall 12 via an end portion of the outlet channel located therein the channel part 23 leads to an outlet opening 24, which can be positioned in the axis 20 or directed at right angles thereto.

For measuring a medium charge to be discharged with one piston stroke, a dosing mechanism 25 is provided in the bottom region of the medium reservoir 4, which has a dosing chamber 26 constituted by two chamber parts 27, 28 opened and closed as a function of the pump stroke. One chamber part 27 is substantially cup-shaped and is formed by the associated end wall or the cover 7 of the medium reservoir 4. The other chamber part 28 is formed by the associated end portion of the channel jacket 19 which, up to abutment with the bottom face 29, is insertable in closely adapted manner into the jacket of the chamber part 27 and bounds with the latter in the starting position a ring slot-like transfer opening. An obtuse-angled, conical discharge hopper 30 is radially connected to the jacket or bottom surface of the chamber part 27, and its radially inner area forms one boundary of the transfer opening and by means of which the medium can flow out of the medium reservoir 4 onto the bottom surface 29. The bottom surface 29 is appropriately raised towards the center, so that the medium thereon comes to rest in a circular storage means, which is roughly congruent with the flow channel 18.

The chamber part 28 is mounted on the end wall 6 with a mounting support 31 for the channel jacket 19 so as to be displaceable axially between the closed position for the transfer opening and the starting position. An inverted jacket 32 is fixed with its radially outer jacket portion in the passage opening of the end wall 6 and with its radially inner jacket portion to the outer circumference of the end of the channel jacket 19 of the pump piston 13. The two jacket portions pass into one another via a ring portion at their ends remote from the pump piston 13 and located within the medium reservoir 4. Between the two jacket portions, a bearing spring is located on the outer circumference of the channel portion 19 and bears with one end on the ring portion of the inverted jacket 32 and can optionally constitute a restoring spring 34 for restoring the chamber part 28 to the starting position. This restoring spring 34 acting axially with its other end on the pump piston 13 is opposed by a stronger restoring spring 33, which is pretensioned between the end wall 12 and the pump piston 13 about the channel part 23 in the pump chamber 10. The restoring force acting on the chamber part 28 is at least sufficiently large to allow the opening of the dosing mechanism 25 when the restoring spring 33 is in the starting position. As a function of the matching of the two opposing restoring forces, the dosing mechanism 25 can be closed at the start of the pump stroke, or dependent on the pressure of the pump 9, only after a first part of said stroke.

The lower end of the flow channel 18 forms a circular opening 35 which is directed against the bottom surface 29 and which is bounded on the outer circumference of the chamber part 28, on an end of the depressed ring zone of the bottom surface 29 and on the inner circumference by the associated end of the channel part 22, which, when the dosing mechanism 25 is closed, faces with a gap the frustum-shaped, central region of the bottom surface 29. This end of the channel part 22 simultaneously forms a central outlet 36 for the medium to be fed out of the storage or dosing chamber 26 through the outlet channel 21 or the inlet of the outlet channel 29. As a result of the described construction, in the vicinity of the ring opening 35, which in the pump position is significantly constricted compared with the cross-sections of the ring channel 18, an injector 37 is formed with a deflection of the gas flow at the bottom surface 29 by approximately 180.degree.. By the opening area, the closed dosing chamber and the outlet area, a turbulence chamber 38 is also formed for whirling up the medium.

Appropriately, the discharge apparatus 1 operates by the following process. The remote faces of the discharge apparatus 1 formed by the cover 7 and the end wall 12 serve as pressure handles 41, 42 for the one-handed, manual operation of the discharge apparatus. The discharge apparatus can have relatively small dimensions, namely, a diameter of less than 50 mm and a length of less than 80 mm. In the case of manual compression of the two subassemblies 2, 3, initially the cylinder jacket 11 is displaced with respect to the pump piston 13 in opposition to the tension of the restoring spring 33, so that a pressure builds up in the pump chamber 10. As a function of whether a spring-free check valve or a pretensioned pressure-relief valve as the control valve 40 is associated with the circular gas outlet 17 distributed over the flow channel 18, immediately after building up a corresponding overpressure, compressed air is fed into the flow channel 18. Beforehand, medium has trickled into the cup-shaped receptacle of the chamber part 27 from the medium reservoir 14, via the hopper 30, as a result of the manipulations which in any case occur. On reaching a first part of the pump stroke, the chamber part 28 is moved by the restoring spring 33 into the closed position. The air delivered in the meantime and while the transfer opening is becoming narrower, blows virtually all the medium away from the seat for the chamber part 28 until the transfer opening is closed and the chamber part 28 is fixed in stop-limited manner.

The further delivered air, accompanied by whirling up and deflection, carries the medium on the bottom surface 29 with it into the outlet 36, through the outlet channel 21 and outwards through the outlet opening 24. Towards the end of the pump stroke, the tension of the restoring spring 33 can rise to such an extent that the bottom of the chamber part 27 can slightly elastically deform under the pressure of the actuating force manually acting thereon, and it is in fact moved towards the outlet 36, so that, without closing, the opening 35 continuously becomes narrower and the flow rate correspondingly higher. This ensures a very effective and complete emptying of the dosing chamber. If subsequently the discharge apparatus 1 is released, accompanied by the closing of the valve 40, the pump 9 initially returns to its starting position, after which the dosing chamber 26 is again opened, so that immediately medium can flow again. Appropriately, other than the springs, at least one or substantially all the described components are made from plastic.

In the case of the construction according to FIG. 2, the pump 9ais located on the end of the medium reservoir 4a remote from the outlet opening 24a, so that the pump chamber 10a, does not have to be traversed by a channel. It has in the bottom wall of the pump piston 13a a gas outlet 17a directed in the discharge direction and which directly issues into one end of the substantially linear flow channel 18a, whose other end forms the outlet opening 24a. The valve 40a has a spherical valve body 43 located at least partly within the associated end of the flow channel 18a and which is spring-loaded towards the closed position with a valve spring 44 located in the flow channel 18a.

The channel jacket 19a of the flow channel 18a traverses the medium reservoir 4a and is provided with a plurality of substantially radial transverse channels 36a in the form of approximately linear jacket openings distributed over the circumference, and in its longitudinal direction and through these, medium can pass in finely divided form from the medium reservoir 4a into the flow channel 18a. In FIG. 1 a slide valve 39 for the medium is formed by the chamber parts 27, 28. In FIG. 2, a transfer control 39a is provided here and the cross-sectional shape, length, individual width and total width of the transverse channels 36a are adapted to the flow behavior of the medium to be discharged.

In this case, the piston 13a is fixed in positionally rigid manner by means of a snap connection 15a directly to the associated end of the casing of the medium reservoir 4a. The two subassemblies 2a, 3a are interconnected by means of a corresponding snap connection 14a. The two snap connections 14a, 15a can be provided on separate, sleeve-like telescoping jacket portions of the reservoir casing, whose space appropriately tapers in funnel-like manner towards the gas outlet 17a. The channel jacket 19a is fixed between the end walls of the medium reservoir 4a and traverses the cover 7a, which can be removed for refilling, and which in this case, is located at the end of the medium reservoir 4a adjacent to the outlet opening 24a. The pump chamber 10a is closed at the end remote therefrom by a corresponding, snapped-in cover 12a, which has the valve-controlled gas inlet 16a. Otherwise, in FIG. 2, corresponding parts are given the same reference numerals as in FIG. 1, but followed by a letter "a".

On operating the discharge apparatus 1a in the above described manner, firstly, a pressure is built up in the pump chamber 10a until the valve 40a opens. As a result, any residual medium which has sunk in ring-like manner around the valve body 43 is suddenly whirled up. As the air flow flows along the radially inner ends of the transverse channels 36a, medium is torn therefrom in predistributed form, further mixed by whirling up with the air flow and discharged through the outlet opening 24a.

Individual features, components and functions of the two embodiments can be provided together in a single embodiment.