Inhalation-initiated Aerosol Dispenser

Abstract

For dispensing to a respiratory patient single discharges of metered aerosol medication, a conventional aerosol container designed to deliver in response to a single actuation a metered amount of aerosol compound, is combined with a chamber partly formed by a breath-operated membrane linked with a spring-retained catch and latch actuator which on release by the inhalation-deflected membrane presses on the metering valve of the container delivering a single discharge in exactly timed relation with the patient's breathing, and also opens a valve communicating with the outside, to admit free air during the final part of the aerosol discharge for continued inhalation. The actuator linkage and the air valve have to be reset by hand to ready the device for the next cycle of operation. In an especially compact embodiment, a unitary housing fully encloses the aerosol bottle which is inserted through an opening closed by a retention cover hinged to the housing. A flexible strap serves as a protective cover for the mouthpiece and the air ingress valve, as well as for resetting the mechanism which it locks when covering the valve and the mouthpiece. The actuator linkage has two straight levers at right angles with the catch and latch at their intersection, and the spring tangentially correlated with the breath-responsive membrane.

Parent Case Text

The present invention is a continuation-in-part of the copending application of Willis A. Kropp, Ser. No. 759,652, filed Sept. 13, 1968, now abandoned.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to medicators of the type which dispense an atomized compound from an aerosol container for inhalation such as by respiratory tract patients.

2. Description of the Prior Art

It is now fairly common practice to dispense pharmaceutical compounds from aerosol devices which upon triggering by finger depression of their valves eject a metered amount of the pressurized compound. Such finger-operated devices are less than fully satisfactory because of the difficulty of obtaining exact correlation of their control with the breathing rhythm of the patient. Especially in the case of children and aged people, the patient is in many instances unable to coordinate his breathing with the valve manipulation. Also, conventional devices of this type do not sufficiently guard against the application of overdosages of respiratory drugs which are sometimes very potent and may produce unwanted side effects. Dangerous overdosage is not at all uncommon with such conventional devices because their users are mainly patients who are short of breath and liable to experience confused breathing of irregular cycle. Such patients are tempted to provide additional inhalation by triggering their device when they sense that their breathing is not deep enough or that the previously discharged inhalation was not applied at the most advantageous portion of the breathing cycle.

SUMMARY OF THE INVENTION

Objects of the present invention are to avoid the above-mentioned difficulties with conventional aerosol respiratory devices, by positively providing a single exactly metered discharge when the inhalation force has reached the most suitable level for accepting medication, and by allowing for the deepest possible penetration into the patient's respiratory tract.

Specifically, the operational object of this invention includes control by optimizing two factors. On the one hand, the preferred embodiment affords sufficient breath-actuated pressure resulting from adequate area so as to make available sufficient force to operate the release valve with ample safety factor. On the other hand, sufficient breath potential or differential with respect to atmosphere is required to initiate operation and subsequent rapid passage of air and pressurized medicament into the respiratory area as the two pressure differentials are equalized which may be likened to an implosion wherein air under ambient pressure rushes to fill a void or partial void. This implosion principle facilitates deeper medicament penetration. In addition the present invention provides any desired degree of volume so that operation is limited to lung inhalation rather than sucking which is caused by cheek contraction which is high in pressure differential but low in volume. Evidence of sufficient volume within the breath chamber responds to the relatively low pressure differential and high volume of lung inhalation and this precludes operation by sucking even though sucking force is much higher than inhalation force.

Further objects are to minimize overdosage by requiring manual resetting previous to each discharge, to amplify prior to use the minimal power source which an average person can produce by way of an inhalation pressure, namely approximately one-half p.s.i.g. to make operation independent of correlation between spontaneous breathing and conscious valve operation, and to utilize the metering provisions of readily available aerosol devices which provide the metered recharge immediately upon each previous discharge without a special metering manipulation.

Objects peculiar to the second embodiment described are optimal compactness, built-in provisions whose use is inherently induced after completed inhalation for the purpose of resetting the mechanism as well as completely closing all openings of the dispenser permitting it to be carried in a pocket or bag, and, in spite of complete safety and effectiveness in operation, inexpensive construction and manufacture which permit use either as a disposable or as a reusable appliance.

For accomplishing these and other objects, the invention combines a conventional aerosol container designed to furnish upon pressure exertion on its nozzle member a single metered discharge, with discharge-actuating mechanism within a control chamber which receives the nozzle member through a sealed opening. The control chamber has, in addition to a sealing opening for the aerosol container, a movable wall portion (such as a membrane, bellows, or piston component) of appreciable area to provide ample unit pressure, an inhalation and discharge aperture for the user, and an air admission valve port. The discharge-actuating mechanism within the chamber is capable of storing energy for release as a force operating the valve nozzle member, and a valve body for closing the valve port during energy-storing condition. The actuating mechanism releases the operating force responsive to movement of the said wall portion in response to a pressure transfer member, when the pressure within the chamber is reduced by inhalation at the discharge aperture. In the embodiment described, the actuating mechanism includes a catch which upon movement by the breath-deflectable member releases a normally engaged latch in response to a deflecting inhalation. The released latch puts into action a spring which causes the mechanism to press on the nozzle member of the aerosol container to release a single metered discharge, and to move the valve body to open the valve port. The actuating mechanism is very compact so that the control chamber can have ample volume with a large breath-responsive wall portion, giving the beneficial effect herein explained.

Repetition of the single discharge cycle is possible only upon reengagement of catch and latch and tensioning of the spring by manual resetting of the mechanism, such as by a flexible member projecting from the valve body through the valve port.

The breath-deflectable wall portion exerts unit pressure on a transmitting member and triggers the actuating mechanism, whereas the nozzle pressure force is supplied by the spring.

In one embodiment described, the latch and the catch are carried at adjacent ends of levers such as two bellcranks pivoted on the chamber wall, the spring is floatingly arranged between the two cranks, and the breath-deflectable member is a membrance stretched over a window of the chamber which membrane is force transmittingly associated with the catch lever by way of a pressure plate that is linearly guided within the chamber.

In the second embodiment described, the latch and the catch are disposed on straight levers arranged at right angles with the latch and the catch at their intersection, the catch responding to the breath-actuated wall portion. This mechanism is actuated by a spring which, upon release by the catch of one lever, of the latch of the other lever, forces the latter to impinge on the nozzle piece of the aerosol dispenser associated therewith. The spring biases the movable wall portion directly, by tangential contact therewith. The resetting mechanism is a strap wide enough to serve as a cover for the air admission valve port and for the inhalation aperture on which it can be locked. This strap, when pulled without closing aperture and valve, resets the actuating mechanism to tensioned position ready for inhalation release. However, when the inhalation aperture and the value port are closed, the unit will not operate, since the closing of aperture and port serves the dual purpose of sealing and preventing spurious operation while in transit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation of the device according to a first embodiment of the invention, seen from the side of the mouthpiece;

FIG. 2 is a section on lines 2--2 of FIG. 1;

FIG. 3 is a section similar to FIG. 2 of the control compartment only, with the air valve open, the latch and catch levers disengaged upon actuation of the membrane, and with the aerosol container discharging;

FIG. 4 is a section on lines 4--4 of FIG. 2;

FIG. 5 is a section on lines 5--5 of FIG. 2;

FIG. 6 indicates a modification with undivided casing;

FIG. 7 is a fragmentary section on line 2--2 indicating a modification with a bellows device instead of the membrane of FIGS. 2 to 5;

FIG. 8 is a fragmentary section on line 2--2 indicating a further modification with a piston instead of the membrane;

FIG. 9 is a side elevation and FIG. 10 is a top view of a second embodiment of the invention;

FIG. 11 is a section on lines 11--11 of FIG. 9 showing the resetting and cover mechanism in locked position, with the latch slightly beyond cocking position to permit return to latch and catch engagement after accidental depression of the membrane;

FIG. 12 is a fractional section similar to FIG. 11 but showing latch and catch in cocked position upon unlocking and release of the resetting strap;

FIG. 13 is a section similar to FIG. 11, showing the dispenser in operation during inhalation;

FIG. 14 is a section on lines 14--14 of FIG. 11;

FIG. 15 is a section on lines 15--15 of FIG. 11;

FIG. 16 is a fractional section on line 16 of FIG. 11, showing the hinge of the bottle holder;

FIG. 17 is a view of the multiple purpose strap;

FIG. 18 is a front elevation of the discharge nozzle;

FIG. 19 is a bottom view of the discharge nozzle; and

FIG. 20 is an elevation of the linking lever.

DESCRIPTION OF A FIRST EMBODIMENT

As shown in FIGS. 1 and 2, the apparatus according to this embodiment of the invention is completely enclosed in a casing 10 which is divided into a control and discharge chamber 11 and a container shell 12. The chamber 11 and the shell 12 are joined by means of a bayonet joint as indicated at 14 of FIG. 1. The shell carries a pin and the chamber a corresponding slot 14.1 which constitute the said bayonet connection. The shell 12 has an elastic member, such as rubber biasing cushion 15 (FIG. 2) and the chamber has a sealing gasket 16 which together securely hold the conventional aerosol bottle 20 within the shell, between the shell bottom 12.1 and the ledge 21 of the chamber which surrounds an opening 20.1 for the neck of the bottle. The discharging valve nozzle 21.1 of the container, on stem 21.2, reaches well into the chamber into the proximity of, and for actuation by the projection 68 of lever 61, as will be described below. The compartment 11 has four indentations 18.1, 18.2 (FIGS. 1, 2, 3 and 4) and 19.1, 19.2 (FIGS. 2, 4) which form interior recesses accommodating the actuating mechanism and provide walls for mounting pins, as will be described below.

The control and discharge chamber 11 has the above-mentioned bottle-holding ledge and indentations, and in addition a mouthpiece 22 constituting a suction and discharge aperture, an actuator window 23, and a valve port 24. The actuator window is covered by an air-pressure-deflectable member such as a plastic membrane 26 stretched over the opening of window 23 and suitably sealed to the adjacent rim 23.1 of the compartment.

A pressure member 31 has a flat disc-shaped portion 32 in force-transmitting relationship with the air-pressure-deflectable member such as membrane 26. Two arms 33 and 34 extend downwardly from the disc 32. These arms carry pins 36 and have slots 37, 38 (FIGS. 2, 3, and 5). The slots 37, 38 slide on a pin 39 pressed into the walls 41, 42 formed by the indentations 19.1, 19.2, as indicated in FIGS. 2, 4 and 5. As shown in FIGS. 2, 3, 4 and 5 the pin 39 also serves as a pivot for the hub 62 of the actuating lever to be described hereinbelow, in addition to guiding the slots 37 and 38 of arms 33 and 34.

A linking lever 51 is pivoted on pin 52 fixed on the walls 43, 44 of the indentations 18.1, 18.2 mentioned above, as shown in FIG. 4. This linking lever is a bellcrank with a hub 53 (FIG. 4) for pin 52. One arm 51.5 has at its end a catch surface 55 (FIGS. 2 and 3). The other arm 51.2 is forked at its end as indicated at 51.21 and 51.22 (FIGS. 3 and 4). Each tine 51.21, 51.22 is slotted to provide insertion of articulating pins 36 of the arms 33, 34 of the pressure member 31.

An actuating lever 61 in the shape of a bellcrank similar to the linking lever 51, is pivoted with a hub 62 on the pin 39 which, as mentioned above, also guides the arms 33, 34 of the pressure member 31. At the end of its arm 61.1, the actuating lever 61 has a latch 64 (FIG. 5). The other arm 61.2 of the actuating lever 61 carries a stud 63 with a valve body 65 (FIGS. 2 and 4). This valve body 65 is made of material capable of sealing the valve opening 24, such as soft rubber. The stud 63 has attached thereto a cord 66 with suitable gripping means such as a ball 67 which permits one to reset the mechanism by pulling thereon, as will be described. A projection 68 of the latch arm 61.1 of actuating lever 61 is arranged for contacting the valve nozzle 21.1, fitting over the conventional stem 21.2, both being conventional parts of the aerosol container 20.

A spring or similar force-exerting means 71 is stretched between the actuating lever and the linking lever, biasing the actuating latch bellcrank 61 as well as the linking bellcrank 51 in clockwise direction, normally retaining the catch and latch portions 55, 64, in contact. It will be noted that the clockwise torque on 51 is slight as compared to that of 61. The valve member 65 is made of material having considerable compression latitude so that the relative positions of the latch and catch members are not critical.

As shown in FIG. 6, the shell can be made integral with the aerosol bottle as indicated at 12.1 and provided with bayonet slots 14.1 to fit corresponding pins of the compartment with the mechanism. This arrangement makes the bottle proper a supplementary part of the valve, precludes the use of undesirable compounds and facilitates labeling.

Instead of the above-described membrane constituting a movable wall portion of the chamber 11, a bellows device such as shown in FIG. 7 can be used. In that figure, the rim of the chamber window 23.1 carries, suitably sealed thereto, a commercially available bellows ring 26' which is on its inner periphery similarly sealed to a plate 32' which is somewhat larger than the disc 32 of FIG. 2.

A further modification is shown in FIG. 8. In this figure, the chamber 11 has an extended cylindrical rim portion 23', and the plate 32" has an inwardly extending sleeve 26". In order to obtain the desirable sensitivity, sufficient sealing without excessive friction has to be provided to fulfill the requirement of easy response to inhalation without resort to sucking.

The operation of the above-described device is as follows.

In normal position the control apparatus within the chamber 11 is in the position shown in FIG. 2, with the catch 55 and the latch 64 engaged, the valve 24, 65 closed and the pressure extension 68 of crank 61 distanced from the nozzle portion 21.1 of the aerosol device 20.

When the patient inhales through the mouthpiece 22, the membrane 26 is deflected inwardly, the inhalation force being dependent upon the area of the membrane. Upon moving inwardly, the membrane presses against the disc 32 of the pressure member 31 which causes the bellcrank 51 to rotate counterclockwise against the force of spring 71, which however in this leverage position exerts only a minimal torque. Upon the counterclockwise rotation of bellcrank 51 the catch 55 releases the latch 64 and the bellcrank 61 thereupon is moved clockwise by the spring. This movement takes place with considerable force and the projection 68 of 61 presses on the top surface of the aerosol valve 21.1, causing it to deliver its single metered discharge. At the same time, with bellcrank 61 rotating clockwise, the valve body 65 is lifted from the seat 24 allowing free air to enter the inside of the chamber and this air is inhaled by the patient somewhat subsequently to the discharge proper. The inhalation vacuum level required for operating the device and the ingress of atmosphere through the valve 24, 65 can be readily predetermined to facilitate deep penetration of medicament into the respiratory tract of a patient.

Upon delivery of this single discharge which cannot be repeated by consecutive inhalations, the device has to be reset by pulling the ball 67 which rotates bellcrank 61 counterclockwise, closes the valve 24, 65 and reengages the latch and catch members of the two bellcranks, and lifts the actuating projection 68 from the nozzle member 21.1 of the aerosol container. The device is thereupon ready for the next discharge.

DESCRIPTION OF A SECOND EMBODIMENT

This embodiment has an ultimately integral casing indicated at 100 in FIGS. 9, 10 and 11, consisting initially of two shells 101, 102, respectively, which after assembling the internal mechanism are temporarily joined by interlocking the tongue and groove profiles indicated at 100.1 in FIGS. 14 and 15. These profiles are molded around the shell edges, excepting the five openings to be described below. The two shells are mirror images of each other, excepting for a few details such as locating pins which are standard expedients in this technique of fabricating molded articles.

As indicated in FIGS. 10, 11, 13, 14 and 15, the housing which will now be treated as an entirety such as after permanent sealing of the two shells, has two sidewalls 105, 106, a front wall 107, a partition 108, a mouthpiece 122, a valve port 124, and an insertion opening 125 for the aerosol container. The housing wall opposite the partition 108 is initially open with a peripheral groove 101.1 and a lip 101.2 (FIG. 11) to which the air-deflectable member such as the membrane 126 is sealed upon completion of the assembly. The partition 108 leads into the front wall 107 with a ledge portion 121 which surrounds an opening 120.1 for the neck of the aerosol container 120. As compared to the first embodiment which is shown with a normally upright aerosol container, in this embodiment the container is shown as being inserted with its discharging valve nozzle block 121.1 and stem 121.2 pointing downwardly. The nozzle block reaches into the actuating lever 161 as will be described below.

In addition to the above-described openings, the housing has a slit 124.1, next to the valve port 124, for insertion of a resetting strap 182 to be described below.

The opening 125 for inserting the bottle is provided with a bottle-holding lid 112 which is hinged to the sidewalls 105, 106 by means of two stubs 112.1 (FIG. 16), one extending on each side, which are pivoted in corresponding recesses 112.2 of the walls. At the other end of the lid 112 is a ratchet lock with a grip handle 112.5 and teeth 107.1, 107.2 on either side thereof (FIG. 10) which engage corresponding teeth 107.5, 107.6 on either side of a cutout 107.8 (FIGS. 10 and 11) of the wall 107. By means of the grip 112.5, the respective teeth can be engaged thereby firmly pressing the aerosol container 120 against the ledge 121 thus securely attaching and satisfactorily sealing it to the housing. This ratchet lock of the bottle holder accommodates a generous tolerance latitude for somewhat varying lengths of bottle 120. It will be noted that crevices around the bottle-holding lid 112 are pneumatically inconsequential because the bottle compartment is sealed from the rest of the housing at the ledge 121.

The membrane 126 of yielding material has a groove between two lips as indicated at 126.1 (FIGS. 11, 14 and 15), shaped to engage the corresponding peripheral groove 101.1 and lip 101.2 of the housing 100.

As shown in FIG. 15 the insides of walls 105, 106 of the housing are provided with recessed bosses 201, 202, 203, 204 serving to receive the stud fulcrums of the levers to be described below. In addition, the sidewalls have recesses, similar to the lid pivot recesses marked 112.2 in FIG. 16, to accommodate a pin 172 for the fixed end of spring 171.

The pressure-collecting member consists in this embodiment of a plate 132 (FIGS. 11 and 14) with two flanges 133, 134 which have split pivot holes 135 (FIG. 11) for receiving the pivot pin 136 of the linking lever 151. The plate 132 extends practically over the entire area of the membrane 126, as shown in FIGS. 11, 14 and 15.

The linking lever 151 (FIGS. 11, 14, 15, 20) is pivoted on two studs 151.1, 151.2 in the recessed bosses 202, 204 above described with reference to FIG. 15. The linking lever also incorporates an arcuately moving pin 136 extending on either side of the hub 136.1, engaging and pivoted in the split holes 135 of the two flanges 133, 134 of the pressure plate 132. The saddle 137 of lever 151 receives the lateral bias of the spring 171 (FIGS. 11 and 14). The other end of the linking lever 151 is molded to form between the studs 151.1 and 151.2 a catch face 155 as shown in FIGS. 11 and 20. The above-described parts of the linking lever 151 are molded in one piece.

The actuating lever 161 (FIGS. 11, 14 and 15) has two flanges 161.1 and 161.2, and a web 161.3 with a cross bridge 162.4. The web 161.3 has a bulge or cam projection 168 for contacting the nozzle block 121.1 of the aerosol container during operation as indicated in FIG. 13. The actuating lever 161 is pivoted on two studs 161.6 and 162.7 (FIG. 15) in the recessed bosses 201 and 203 of the housing. Opposite the pivot 161.6, 162.7, the actuating lever has latch faces 162 recessed on the two flanges 161.1, 161.2 and thus adapted to engage the catch face 155 of the linking lever 151. Opposite the bridge 162.4, the web 161.3 carries a valve body 165 of material capable of sealing the valve opening 124, such as soft rubber as described in the first embodiment. Attached to a lip 163 of the actuating lever is a cover and strap member indicated generally at 181 with a pull strap 182, a breathing aperture cap 185 and a pull tab 186 (FIGS. 9, 11, 13 and 17). The end of the strap 182 passes through the slit opening 124.1 of the housing and is scored just outside thereof as indicated at 183 in FIGS. 11 and 17. A tab portion 184 of the strap is sufficiently long and wide to cover the valve aperture 124 at the bottom of the housing as indicated in FIGS. 11 and 9 and then widens to form the cap portion 185. It ends in a tab and locking portion 186 which has a lip 187 formed to interlock with a corresponding rim 188 of the breathing aperture. If this locking arrangement is disengaged and the strap 181 hangs down, the scored strap end 182 (and a portion of 184) which is attached to the lever 161 is capable of passing through the slit 124.1, permitting the lever 161 to move inwardly.

At the swinging end of the lever 161 is provided a hole 180 for a hook at one end of the spring 171 which is at its other end attached to the pin 172 inserted between two recesses of the housing, as above described. This spring 171, stretched between the points 172 and 180, contacts the saddle 137 of the linking lever 151 at its moving pivot on the pressure plate 132, biasing the pressure plate towards the membrane 126.

The two flanges 161.1, 161.2 of the actuating lever 161 secure the nozzle block 121.1 against rotation while permitting it to be distanced from the aerosol-releasing bulge 168 of the actuating lever web 161.3. As indicated in FIGS. 18 and 19, the nozzle block has preferably on its lower face an indicator, such as an arrow 191 in order to facilitate insertion of the bottle with the nozzle 192 pointing in the correct direction.

The above-described embodiment is made from suitable plastic material, such as medium impact styrene for the internal mechanism and the housing proper, a softer material such as "Thermolastic" available under that trade designation from the Shell Company for the breath-responsive membrane, and polypropylene for the cover 181 with tab and cap and the bottle holder 112.

For assembling the inhaler, the mechanism with the two levers, the spring, the pins, and also the strap and bottle holder are in proper relation located in one shell, and the other shell is then snapped on by means of the tongue and groove edges. The membrane is applied in similar fashion. The two shells may then be permanently sealed to each other, and the membrane to the shells, by applying ultrasonic vibration energy in the manner well known in the art of fabricating plastic articles.

The sealed housing is essentially a parallelepiped with the membrane 126 forming one long and narrow side thereof, the container opening in one short and narrow side, the air admission port in the other short and narrow side, and the suction and discharge aperture at the edge formed by the other short and narrow side and the long and narrow side opposite the membrane. The partition 108 of the bottle compartment is parallel to the membrane 112, and the bottle-sealing ledge 121 is normal thereto.

The operation of the above-described second embodiment of the invention is as follows:

In order to make the inhaler ready for operation, the bottle holder 112 is opened, an aerosol container 120 of suitable size is inserted, and the holder 112 secured with the lock 112.5. During insertion of the container, the nozzle block is advanced through the opening 120.1 of the rim 121 until paralleled by the two flanges of the actuating lever 161 as shown in FIG. 15. Correct placement of the nozzle opening 192 is facilitated by the arrow embossed on the block, as shown in FIG. 19. The cover 184 is by its tab 186 pulled over the valve port 124 and the mouthpiece 122, and secured by engaging the tab with the lip 188. In this condition the device is secured against accidental operation including depression of the membrane 126 and can be safely carried in a pocket or bag. The disengagement of latch 162 and catch 155, as shown in FIG. 11 provides a condition which precludes inadvertent discharge and the necessity for recocking should the membrane be accidentally depressed sufficient for normal operation.

For using the inhaler, the strap 181 is released at its locking portion 187, 188 to uncover the mouthpiece 122 and also the valve port 124. Subsequent to inhalation, it will then be in the position shown in FIG. 13. As indicated by the facial silhouette in FIG. 13, prior to inhalation the opening 122 is inserted in the mouth of the patient who can easily hold the inhaler in one hand since it can be made very small, such as not more than about 4 inches high. The first inhalation will deflect the membrane 126 as indicated in FIG. 13, moving the pressure member 132 against the pressure of spring 171 at its saddle 137, which is incidental to operation but essential for resetting. The lever 151 turns on its pivots 151.1 and 151.2 and releases the catch 155 from the latch 162 of the actuating lever 161. This lever, turning on its pivots 161.6, 161.7 is pulled forcefully upwardly by the spring 171, and its impingement projection 168 pushes the nozzle block 121.1 upwardly, thus causing the aerosol container to discharge as indicated by arrows in FIG. 13. Air is simultaneously admitted through port 124.

As described above with reference to the first embodiment, the above-outlined single discharge cannot be repeated by consecutive inhalation since the latch and the catch are safely disengaged with the nozzle block 121.1 fixated by the tension of the spring 171. For repeated use, the device has to be reset by pulling on the strap 181 which will turn the lever 161 downwardly for engagement of its latch 162 with the catch 155 of the linking lever 151. The operation can then be repeated, or if the treatment is for the time being terminated, the tab 186 may again be engaged at 188 thus safely securing the lever 161 in its triggered position and at the same time closing the mouthpiece 122 with the cap 185, and the valve with the strap 182. It will be evident that storing of the cocked device with the cover 181 hanging down would be quite inconvenient, the tab reminding the user of the insecured position, and providing strong inducement to lock the cap.

Due to the present peculiar coordination of the latch and the catch, as comparatively indicated at FIGS. 11 and 12, respectively, the secured resetting strap locks the biasing member by snubbing action which prevents spurious operation, during travel for example, as follows. As indicated in FIG. 11, the catch and latch surfaces 155 and 162 are separated when the mouthpiece is closed, rendering ineffective any accidental movement of the membrane 126 and the linking lever 151. Thus, if the moving walls were accidentally depressed the mechanism will return to a position in readiness for operation when the accidental depressing force is removed. When the mouthpiece cap and resetting strap are released, the two surfaces 155 and 162 will contact as shown in FIG. 12, thus perfecting readiness for triggering by a comparatively very slight inhalation pressure pulling at the inside of the membrane.

It will now be evident that the second embodiment facilitates manufacture and provides a particularly simple as well as accidentproof and tamperproof construction. It was found that the spring as used in the second embodiment provides strong aerosol-releasing impact energy for actuating the trigger arrangement, but provides a lesser trigger-cocking force more softly but also more effectively responsive to slight inhalation under pressure, by biasing the linking member against the side of the spring at right angles to a line subtending the spring anchorage points.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall within the scope of the appended claims.

Claims

I claim:

1. An inhalation-actuated dispensing device adapted to receive a conventional aerosol container of the type having a container body and a valve means mounted on said container body, said valve means releasing a metered amount of aerosol compound when moved toward said container body and reloading upon moving away from said container body and to actuate said valve means to release said metered amount of aerosol compound at a predetermined portion of the inhalation phase of a breathing cycle, said device comprising,

a walled chamber,

an apertured portion of said chamber forming a mouthpiece,

aperture means in said chamber in the vicinity of said mouthpiece for receiving the valve means portion of said container within said chamber in position to discharge said metered amount of aerosol compound through said mouthpiece,

means for at least temporarily retaining said aerosol container in a fixed position relative to said chamber with the body of said container outside said chamber and the valve means portion in position within said chamber,

a window in said chamber remote from said mouthpiece,

an air-deflectable member comprising a movable wall portion associated with said window and adapted to move between a first position in which said movable wall portion at least substantially fills said window and a second position toward the interior of said chamber relative to said first position,

a linking lever pivotally mounted within said chamber,

said linking lever having a catch means and a portion associated with said movable wall portion to cause said lever to move about said pivot responsive to the motion of said movable wall portion,

an actuating lever pivotally mounted within said chamber,

said actuating lever having a latch means adapted to cooperate with the said catch means on said linking member and having a portion adapted to press against said valve means on said aerosol container,

spring means to bias said movable wall portion to the said first position and correspondingly said catch toward the said latch and to move said actuating lever into pressing engagement with said valve means when said catch and said latch are released,

said movable wall portion, said linking lever, said catch, said latch, said actuating lever and said spring means together constituting an actuating mechanism,

resetting means associated with said actuating lever and passing to the outside of said chamber adapted to move said actuating lever against the force of said spring means to remove said actuating lever from pressing engagement with said valve means and to move said latch into position to contact and engage said catch,

air valve means associated with said actuating mechanism at a position remote from said mouthpiece relative to said valve means to admit air freely from the outside of said chamber responsive to the motion of said movable wall portion from said first position to said second position,

said chamber, when said movable wall portion is in said first position, being substantially isolated from the ingress of free air except through said mouthpiece,

whereby when said actuating mechanism is in a normal cocked condition with the movable wall portion in said first position and with said catch means contacting said latch means, the egress of air from said chamber through said mouthpiece as in the inhalation phase of a breathing cycle actuates said actuating mechanism by causing said movable wall portion of said air deflectable member to move from said first position to said second position thereby rotating said linking lever about its pivot releasing said catch from said latch thereby releasing said actuating lever to press against said valve member releasing a metered charge from said aerosol container, the actuation of said actuating mechanism simultaneously opening said air valve means to freely admit outside air into said chamber.

2. An inhalation-actuated dispensing device as claimed in claim 1 wherein said movable wall portion includes a plate member which substantially fills said window when in said first position with the peripheral edge of said wall portion in close proximity to but separated from the rim of said window.

3. An inhalation-actuated dispensing device as claimed in claim 1 wherein said movable wall portion includes a flexible membrane means extending over said window and affixed to the rim thereof.

4. An inhalation-actuated dispensing device as claimed in claim 1 wherein said movable wall portion includes a bellows ring means arranged in flexing relation between the periphery of said wall portion and the rim of said window.

5. An inhalation-actuated dispensing device as claimed in claim 1 wherein said means for retaining said aerosol container in a fixed position relative to said chamber includes a shell means formed integrally with said chamber, a ledge portion of said shell means surrounding said aperture means for receiving the valve means portion of said container adapted to receive in sealing engagement that portion of the container body surrounding said valve means, and means for retaining said container body and pressing the same against said ledge.

6. An inhalation-actuated dispensing device as claimed in claim 5, wherein said shell means comprises a container housing and said means for retaining said container body comprises a movable member associated with said container housing adapted to press against that portion of said container body opposite said valve means.

7. An inhalation-actuated dispensing device as claimed in claim 6, wherein said movable member comprises a container-holding lid pivotally mounted at one end to said housing and provided with a ratchet lock adapted to engage corresponding teeth on the wall of the container housing at the other end.

8. An inhalation-actuated dispensing device as claimed in claim 5, wherein said shell means is generally cylindrical in shape, is provided with end closing means including an elastic biasing member adapted to press against that portion of said container body opposite said valve means and an intermediate disconnect portion.

9. An inhalation-actuated dispensing device as claimed in claim 8, wherein said disconnect portion comprises a bayonet joint.

10. An inhalation-actuated dispensing device as claimed in claim 1 wherein said resetting means includes a pull strap and a cover means, said cover means adapted to removably cover said mouthpiece.

11. An inhalation-actuated dispensing device as claimed in claim 10, wherein said cover means includes means wherein when said cover means covers said mouthpiece there is sufficient tension on said strap to retain said latch beyond the contact point with said catch whereby accidental movement of said movable wall portion will not uncock said activating mechanism.

12. An inhalation-actuated dispensing device as claimed in claim 1, wherein said linking lever and said actuating lever are substantially straight members, said linking lever being pivotally mounted at an intermediate point with said portion associated with said movable wall portion on one face of said lever on one side of said pivot and said catch on the opposite face of said lever on the other side of said pivot and said actuating lever being pivotally mounted at one end adjacent said mouthpiece having said latch means at the end opposite said pivot and the portion adapted to press against said valve means on one face of said lever intermediate said pivot and said latch.

13. An inhalation-actuated dispensing device as claimed in claim 12, wherein said spring means extends under tension generally parallel to said linking lever between a point on said actuating lever adjacent said latch and a point associated with said wall of said chamber beyond the portion of said linking lever associated with said movable wall portion.

14. An inhalation-actuated dispensing device as claimed in claim 13 wherein the side of said spring rests against a point on said linking lever adjacent the portion of said lever associated with said movable wall portion thereby biasing said movable wall portion toward said first position.

15. An inhalation-actuated dispensing device as claimed in claim 12 wherein said air valve means comprises an air valve body mounted on said actuating lever adjacent said portion adapted to press against said container valve means but on the opposite face of said lever and an associated air admission port in the wall of said chamber.

16. An inhalation-actuated dispensing device as claimed in claim 15 wherein said resetting means is a strap member passing from the end of said actuating lever through an aperture adjacent said air admission port in the wall of said chamber, said strap member having a cover portion adapted to removably cover said mouthpiece and an intermediate widened portion adapted to cover said air admission port opening when said mouthpiece cover portion is in covering position.

17. An inhalation-actuated dispensing device as claimed in claim 1, wherein said linking lever and said actuating lever are each a bellcrank pivoted at a midpoint, wherein the portion of said linking lever associated with the movable wall portion is adjacent the end of a first arm of said linking lever bellcrank and said catch means is adjacent the end of a second arm of said linking lever bellcrank, and wherein said latch means is adjacent a first arm of said actuating lever bellcrank and said portion of said actuating lever adapted to press against said valve means is at a midportion of said first arm of said actuating lever bellcrank.

18. An inhalation-actuated dispensing device as claimed in claim 17, wherein said spring means comprises a spring mounted under tension at one end to an intermediate portion of a second arm of said actuating lever bellcrank and at the other end to the second said arm of said linking lever bellcrank adjacent the pivot thereof.

19. An inhalation-actuated dispensing device as claimed in claim 17, wherein said resetting means is located near the end of said second arm of said actuating lever bellcrank

20. An inhalation-actuated dispensing device as claimed in claim 17, wherein said air valve means comprises an air valve body mounted adjacent the end of said second arm of said actuating lever bellcrank and an associated air admission port in the wall of said chamber.

21. An inhalation-actuated dispensing device as claimed in claim 20, wherein said resetting means comprises a flexible member that passes through said air admission port.

22. An inhalation-actuated dispensing device as claimed in claim 17 wherein said movable wall portion is mounted on an arm member, which arm member is slidably engaged at its opposite end with the pivot for said actuating lever bellcrank and the end of said first arm of said linking lever bellcrank is slidingly engaged to a pin at an intermediate portion of said arm member.