US3900138A

US3900138A - Medicament dispenser

Info

Publication number: US3900138A
Application number: US430219A
Authority: US
Inventors: Robert E Phillips
Original assignee: Minnesota Mining and Manufacturing Co
Current assignee: 3M Co
Priority date: 1972-08-07
Filing date: 1974-01-02
Publication date: 1975-08-19
Anticipated expiration: 1992-08-19

Abstract

A dispenser for dispensing inhalable medicaments which dispenser dispenses the liquid medicaments in a mist by nebulizing a metered amount of the liquid. The liquid is metered by a rotary piston pump and a piston and cylinder arrangement within the dispenser compresses a small amount of air when a release mechanism is triggered to carry the dispensed liquid such that the patients will inhale a mist.

Description

United States Patent Phillips Aug. 19, 1975 MEDICAMENT DISPENSER 3.168.213 2/1965 De Gon 222/340 x [75] inventor: Robert E. Phillips, Studio City,

Calif- Primary E.\'uminer-Stanley H. Tollberg [73) ASS-lgnec: Minnesota Mining and AA'A'lAItUl! Examiner-Budd Lane Manu'afluring Company. St Paulv Atlurnt). Agenl, or Firm-Alexander, Sell, Steldt & Minn- DeLuHunt [22] Filed: Jan. 2, I974 [211 App]. No.: 430,219 [57] ABSTRACT Related Applica'ion Dam A dispenser for dispensing inhalable medicaments i 1 Divisim of l973- which dispenser dispenses the liquid medicaments in a lmsyogmist by nebulizing a metered amount of the liquid. a 9 7 S The liquid is metered by a rotary piston pump and a [52] 222/340 /338- U0 piston and cylinder arrangement within the dispenser lift. Cl. 1 i .T compresses a Small amount f air when a release 8] new or Search 222/3401 2 mechanism is triggered to carry the dispensed liquid 222/384; 417/500; "39/338 such that the patients will inhale a mist.

[56] Rderences cued 3 Claims, 7 Drawing Figures UNITED STATES PATENTS 2,898.00) t l/I959 Green 222/340 X 1 I I I E' 148 I d 60 4/ as 6 '64 45/ 40" n 45 1 r r\ 4/ 1' 5-5 42 43 7 36 '70 7 i 2% 1 a; 1 4a 3; "(523/ 52 ady; 2 5 i he /4 7 24359 {5 *3 9 19 vvg PATENTED AUG] 9 I975 saw 2 0f 2 MEDICAMENT DISPENSER This is a division of application Ser. No. 278,538. filed Aug. 7, 1972. now US. Pat. No. 3.818.908, issued June 25, I974.

BACKGROUND OF THE INVENTION This invention relates to a dispenser for medicaments to be inhaled by the patient. and in one aspect to a dispenser which will provide the liquid in a mist form such that it is easily inhaled without the necessity of having the medicine combined with a liquid propellant.

Examples of the dispensers for medicaments which are packaged in containers with a propellant are illustrated in US. Pat. Nos. 3,] 57.l79 and 3,456,644. While these patents are only examples of numerous patents relating to dispensers where the medicament is either a solid or a liquid and soluble or insoluble in the propellant such as the Freon" types of propellants they show the present state of the art on inhalation dis pensers. An alternative dispensing device is shown in US. Pat. No. 2.951.644, wherein an appropriate gas under pressure in a container is used to atomize the medicaments from a reservoir so long as the container is open to allow the gas to develop a partial vacuum over a tube. The tube extends into the reservoir for the fluent and discharges it by atomization.

These prior art devices however all utilize the propellants in some manner to discharge the medicament. The propellant requires careful packaging and it is the purpose of the present invention to avoid the necessity of using propellants in dispensing the medicament and to avoid the packaging requirements which are inherent with the use of pressurized medicaments.

Other prior art exists where atomizers are used to inject a medicament or breath freshener into the oral cavity. These devices have not provided any means for expelling measured amounts of the liquid. It is only coincidental if equal amounts are expelled by different persons operating the devices. Measured amounts to afford prescribed treatment is an essential element of most medicament dispensers.

SUMMARY OF THE INVENTION The present invention provides a dispenser for medicaments such that metered amounts of the medicament will be discharged in a nebulized state and available for inhalation by a patient. The dispenser comprises a tubular housing having a generally cylindrical shape and formed with a laterally extending mouthpiece. Into the housing is assembled a piston like body having a reservoir for the liquid, a metering pump having an inlet communicating with said reservoir and an outlet communicating with the mouthpiece of the housing. An operator is provided for operating a movable piston in the metering pump to dispense a metered amount of said liquid from the outlet under pressure. A mechanical actuator actuates the operator upon the triggering of resettable release means which release said mechanical actuator. Also provided within the housing is a cooperating structure for compressing air and directing the air toward said outlet of the metering pump. This air compressing means is also operated by the mechanical actuator and carries the fluid discharged from the pump outlet through the mouthpiece and nebulizes the same to make it available for inhalation by the patient.

The present invention provides a novel dispenser where the medicament does not have to be packaged with a propellant and one wherein the ambient air is used for discharging the medicament from the dispenser in a mist or nebulous condition. The medicament may be supplied in a replaceable canister including a metering pump or in a replaceable cartridge.

DESCRIPTION OF THE DRAWING The dispenser of the present invention and the advantages thereof will be more fully understood after a perusal of the following description which refers to the accompanying drawing wherein:

FIG. 1 is a perspective view of a dispenser constructed according to the present invention;

FIG. 2 is an exploded view showing the several parts of the dispenser;

FIG. 3 is a vertical sectional view of the dispenser in a set position;

FIG. 4 is a vertical sectional view of the dispenser during operation of the dispenser;

FIG. 5 is a vertical sectional view of the dispenser upon completion of the operation of the dispenser to dispense a metered amount of liquid;

FIG. 6 is a transverse sectional view taken along the lines 66 of FIG. 3; and

FIG. 7 is a transverse sectional view taken along line 7-7 of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing wherein like parts in the several views have similar reference numerals, there is disclosed a dispenser I comprising a tubular housing II formed with a hollowed laterally projecting discharge passageway or mouthpiece I2 to aid the patient in inhaling the discharge from the dispenser. As illustrated the inner diameter of the housing I1 is changed to form a shoulder 14 intermediate the length thereof. The diameter is smaller at the end near the mouthpiece I2. Into the smaller diameter end of the housing is fitted a base 15 which is secured by a bayonet joint. The base I has a first large bore 16 which receives the body 17 defining a replaceable canister. An opening 18 in the side wall of the base will communicate with the mouthpiece 12. The opening 18 as shown in FIGS. 3, 4, and 5 also communicates with a small diameter passageway 19 leading from an axially extending bore 20 having a smaller diameter than that of the bore 16. The passageway I9 is part of the air compression means which will be hereinafter described.

The canister I7 is generally cylindrical and is formed with a first axially extending bore 22 forming cylindrical walls defining a reservoir for a quantity of liquid and a second bore 23 which when the canister 17 is in position will align and communicate with the bore 20 in the base 15. A transverse bore 24 formed in the canister 17 defines a portion of a rotary piston pump for metering the liquid. The bore 24 communicates by an axially extending passage 25 with the reservoir 22 to define an inlet into the pump and an opposed passage 26 communicates with the opening 18 in the base I5 to define an outlet from the pump. A tube or nozzle may be fitted at the end of passage 26 to direct and change the discharge. A recess 28 formed about the bore 24 receives a compression spring 29 which drives a flange 30 secured to a piston 3| toward a charge ormetering position for the rotary piston pump. The piston 3| has a pair of obliquely positioned rings 32 surrounding the piston which 0 rings seal with the bore 24. On the extended end of the piston 31 is a cam follower 33 engageable by an operator 36 defining means for reciprocating and sequentially oscillating the piston through a given angle of rotational movement. The amount of rotation is preferably less than 90 but can be about 180. The reservoir 22 is sealed and vented by a suitable stopper 35.

The operator 36 has the form of a long slender rod having an axially extending tapered cam 37 formed adjacent one end, which upon reciprocation of the rod will cause a reciprocation of the piston 31. At opposite ends of the axially extending cam 37 are

cam surfaces

38 and 39 which cooperate with the cam follower 33 on the extended end of the piston 31 causing the same to rotate about its axis in one direction or the other. Rotation of the piston 31 changes the position of the oblique 0 rings 32 relative to the inlet 25 and outlet 26 such that liquid may be properly metered by the pump and discharged from the pump. The end of the operator 36 opposite the end formed with the cams is formed with a head 40. The head is placed in a key hole slot 51 to secure the rod 36 to a cylindrical body 42 to be here inafter described. Intermittent the ends of the operator 36 is a slot 43 which receives a set screw limiting its travel and preventing rotation of the same during operation. An axially extending groove 41 in the rod 36 provides an air passage from the top of the canister 17 along the rod to the bore and to the air passage 19.

An air compressing means is provided in the dispenser to deliver a charge of compressed air upon operation of the dispenser. This charge of compressed air is directed toward the liquid outlet of the rotary piston pump to nebulize the liquid discharged. The air compressing means comprises the cylinder 42 which is formed with a cylindrical inner bore 45 slidably fitting about the canister 17 in a cylinder and piston arrangement. The inner bore 45 forms the air chamber when the cylinder 42 is in a first position relative to the canister body 17 and the cylinder 42 is driven downward over the canister 17 to compress the air. This air compressing means also comprises the narrow groove 41 formed in the operator 36, which permits the compressed air to move downward through the bore 23 and the bore 20 into the passageway l9 to be directed toward the outlet. Surrounding the open end of the cylinder 42 is a flange 48. This flange slides along the inner bore of a cap 50 to be hereinafter described and is driven toward the shoulder 14 of the housing H. The closed end of the bore 45 is formed with the key hole slot 51 in which the head 40 of the operator 36 may be received and placed in a fixed position. A limit screw 52 cooperating with the slot 43 for determining the position of the operator 36 is threadably received through the wall of the canister body 17 into slot 43.

Mechanical actuating means are provided for moving the cylinder 42 relative to the canister 17. In the illustrated embodiment the mechanical actuator means comprises a compression spring 55 which surrounds the cylinder 42 and bears against a flange 56 formed on a second sleeve 58 which triggers the resettable release means to actuate the actuator to drive the air compressing means and the operator. The sleeve 58 is cylindrical having a closed end wall 59 and is manually reciprocated in the dispenser. The sleeve 58 is formed with axially extending slots 60 and 6] in its side walls to afford limited movement of the sleeve to compress spring before unlocking the release means and the energy of the actuator. The slots and 6] do not extend down to the flange 56.

The resettable release means comprise a pair of

detents

63 and 64 which are received in a diametrical bore 65 in the closed end of the cylinder 42. The

detents

63 and 64 are spring biased outwardly by a compression spring 66 toward the interior walls of the shell 58 and extend through the

slots

60 and 61 toward the inner cylindrical surface of cap 50 to seat above an inwardly projecting rib 68 formed in the cap 50. The cap 50 is seated in the top of the housing 1] and extends down to the shoulder 14. The cap 50 holds the

sleeve

58 and 42 in place between the shoulder 14 and rib 68. The detents are placed in locked position by lifting the sleeves 58. The detents are biased inwardly by the rib 68 engaging beveled ends thereof and then are snapped into place above the rib 68 when the bottom edge of the

slots

60 and 61 reach a position above rib 68.

A keyway 69 in the cap 50 and a pin 70 in the flange 48 of the sleeve 42 prevent rotation of the sleeve and displacement of the operator 36 from the key hole slot 51.

In the set or readied position (FIG. 3 the

detents

63 and 64 are positioned above the rib 68 and the spring 55 is in its expanded position between the

flanges

56 and 48. The piston 31 has been rotated by the dam 39 and follower 33 to close the inlet 25 and the outlet 26 is open. The operator wishing to expel] a metered amount of the medicament then places the thumb against the base 15 and the forefinger and/or the index finger upon the end wall 59 of the sleeve 58 to force the sleeve 58 into the cap 50. The operator should be covering the mouthpiece l2 and beginning to inhale. Continued movement of the sleeve 58 thus causes compression of the spring 55 and eventually the top edges of the

slots

60 and 61 engage the beveled surfaces of the

detents

63 and 64 driving them inward and off of the rib 68. When the detents disengage the rib 68 the energy of the compressed spring 55 (FIG. 4) drives the sleeve 42 down over the canister 17. The pressure upon the shell 58 to compress the spring 55 and then the continued pressure or follow through provided by the operator affords complete movement of the shell 42 and actuates the operator 36 forcing the operator down into the

bores

23 and 20. This drives the piston 31 inward into the bore 24 forcing the medicament therein out through the outlet 26. During the time the compressed air between the top of the canister l7 and the inner cylinder of the shell 42 is forced down through the groove 41 into the bore 20 and through the passageway 19 the medicament is expelled under pressure through the outlet 26 to be struck by the air discharged from the passageway 19 when the air pressure is highest. The medicament is thus carried by the air out through the opening 18 into the passageway of the mouthpiece l2 and into the mouth and air canals of the operator.

When the shell 42 meets the limit of its travel by contact with the upper surface of the canister 17 the operator 36 has driven the piston 31 to its full inward position and the cam follower 33 on the extended end of the piston has contacted the cam surface 38. Cam 38 causes the cam follower to rotate the piston 3| and the 0 rings 32 to assume the position shown in FIG. 5. The operator will now raise the shell 58, lifting with it the sleeve 42 and the operator 36. As this is done the spring 29 reciprocates the piston 31 outwardly and the pump again communicates with the inlet 25 and a metered amount of the medicament is drawn into the cylinder 24 forward of the O ring 32. As the shell 58 is lifted the

detents

63 and 64 are forced inwardly by rib 68 engaging their beveled edges and then are forced outwardly again to seat on the upper side of the rib 68 in the cap 50. Cam 39 again contacts the follower 33 to rotate the piston 31. turning the rings 32 to a position cutting off communication between the pump and the inlet 25. The device is now positioned for a subsequent operation.

In an operative example, the air discharged from the passageway 19 to nebuiize the liquid can be at pressures between and 8 pounds per square inch at standard temperature and atmospheric pressure The bore 45 of the shell 42 has a diameter of about 0.85 inch and it travels a total of 0.8 inch. The shell travels about 0.4 inch to release the spring and when released the pressure therein is about 8 pounds. The spring and the continued movement maintained by the operator then drives the shell 42. The amount of liquid dispensed may be about 5, 6, or 7 microliters. depending on pump capacity.

For preferred operation, a predetermined amount of air under a predetermined amount of pressure is directed at the discharged liquid. The predetermined amount of liquid is introduced into the air stream when the air is at its peak pressure.

Having thus described the invention with respect to a preferred embodiment, it will be understood that certain modifications can be made without departing from the spirit of this invention.

What is claimed is:

l. A canister for supplying medicament to a dispenser comprising:

a cylindrical shaped body member having a first axially extending bore extending toward one end and forming a reservoir. a second bore extending axially through said body member, said body having a third bore with a closed end extending generally diametrically thereto and communicating through axially aligned passageways with said reservoir and with said one end. piston slidably fitted in said third bore to form a pump. said piston having means affording selective communication of said third bore with said reservoir in a set position and with said one end in an expel position,

an axially movable operator having a cam surface positioned in said second bore for moving said piston,

a spring positioned about said piston normally urging it from said bore to engage said operator, and

a medicament stored in said reservoir.

2. A canister according to claim I wherein said piston is provided with an extended end having thereon cam follower means for reciprocating and imparting rotational movement to said piston affording said selectivity in communicating with said reservoir and said one end upon movement of said operator.

3. A canister according to claim 1 wherein said means affording selective communication of said third bore with said reservoir and said one end comprises an obliquely positioned O-ring positioned about said piston and cam follower means for imparting reciprocation and axial rotation to said piston affording said desired selectivity and to expel metered amounts of said medicament from said one end upon movement of said operator.

* a: a k

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3 900 138 DATED August 19, 1975 INVENTOR(S) Robert E. Phillips It is certified that error appears in the above-identified patent and that sard Letters Patent are hereby corrected as shown below:

The Assignee in this patent should be changed from Minnesota Mining and Manufacturing Company, St. Paul, Minnesota to Riker Laboratories, Inc., Northridge, California Signed and Scaled this ninth Day of December1975 '[SEAL] Arrest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner ufParenls and Trademarks

Claims

1. A canister for supplying medicament to a dispenser comprising: a cylindrical shaped body member having a first axially extending bore extending toward one end and forming a reservoir, a second bore extending axially through said body member, said body having a third bore with a closed end extending generally diametrically thereto and communicating through axially aligned passageways with said reservoir and with said one end, a piston slidably fitted in said third bore to form a pump, said piston having means affording selective communication of said third bore with said reservoir in a set position and with said one end in an expel position, an axially movable operator having a cam surface positioned in said second bore for moving said piston, a spring positioned about said piston normally urging it from said bore to engage said operator, and a medicament stored in said reservoir.

2. A canister according to claim 1 wherein said piston is provided with an extended end having thereon cam follower means for reciprocating and imparting rotational movement to said piston affording said selectivity in communicating with said reservoir and said one end upon movement of said operator.