Abstract:
An inhaler for powdered medicaments contained in a capsule which is inserted when needed into an elongated recess by rotatably moving two component portions out of register, perforated by means of biasedly attached piercing devices, and emptied by spinning within a cylindrical spinning chamber when air is drawn through tangentially disposed intake passages, the component portions being held in register by a latching device.

Description:
FIELD OF THE INVENTION 
     The present invention relates to inhalers, and particularly relates to an inhaler for the administration of powdered medicaments. 
     SUMMARY OF THE INVENTION 
     According to the present invention, there is provided an inhaler for the adminstration of powdered substances comprising a body portion having a chamber for receiving a capsule containing powdered substances, piercing devices on the body portion operable to perforate a capsule in the capsule chamber, and air intake passages communicating with the capsule chamber and positioned in such a manner that air drawn therethrough when inhaling air through an inhaler passage leading from the chamber imparts a rotary and shaking motion to a capsule in the capsule chamber. 
     Embodiments of the present invention can be constructed in two main parts, a body portion of the inhaler and a tubular portion or mouth-piece: these two portions are rotatably connected and releasably latched to each other to allow access to the interior of the body portion so as to place a capsule containing the substance for inhalation in position in the capsule chamber. Following perforation of the capsule by the piercing devices, inhalation by the patient through the tubular portion or mouth-piece causes the powder to be drawn out of the capsule and entrained in the inhaled air. 
     Preferably, the air intakes are positioned so that intake air passes tangentially into the capsule chamber. In the preferred embodiment of the invention, the capsule chamber has an elongated recess in the bottom wall thereof, in which recess the capsule in the chamber rests when the inhaler is not in use, and the air intake is drawn from the recess into the capsule chamber by the air passing through the capsule chamber from the intake passages to the inhalation passage upon inhalation. The inhaler of the present invention is convenient and simple to use, of constant efficiency thereby ensuring a consistent dosage, and of small size. 
     The body portion and tubular portion are preferably pivotally attached together, and in the preferred embodiment this is effected by means of a pivot pin, the axis of which is parallel to the axis of the tubular portion by which is eccentrically placed on one side thereof to allow disengagement or locking by a simple revoloution of one portion with respect to the other about an axis parallel to the axis of the tubular portion of the inhaler. 
     Preferably, the piercing devices comprise movable pushbuttons, each carrying a set of elongated spikes positioned to enter a capsule in the recess within the capsule chamber and to effect perforation thereof upon depression of a push button. In the preferred embodiment, there are two such push buttons, each being maintained in a normal position by four independent springs, and each being held in place by rims on the body portion which engage cooperating shoulders on each push button. Each of the push buttons supports four elongated metal spikes. Perforation of a capsule in the elongated recess at the bottom of the capsule spinning chamber is thus simply effected by a simple pressure on one or both of the push buttons. 
     The shape of the elongated recess in the bottom wall of the capsule is preferably substantially the same as that of a conventional medicament capsule, the recess being generally rectangular with rounded ends. Preferably the spikes or pins of the piercing devices are coaxial with the recess so that a capsule is perforated at its ends. The capsule chamber is preferably circular so that a pierced capsule is caused to rotate solely by the tangential intake air upon inhalation. The intake air also acts to draw the capsule out of the recess upon inhalation so that operation is effectively automatic. The diameter of the capsule chamber is slightly larger than the length of a conventional medicament capsule so that there is a small clearance between the chamber and the ends of the capsule as it rotates; this causes a shaking of the capsule as it strikes against the cylindrical wall of the capsule chamber, thereby urging the powder out from the capsule and causing it to be mixed with the intake air upon inhalation. 
     The tubular portion of the inhaler consists essentially of a circular pipe having at one end a base supporting an abutment stop for locating the inhaler body. The base of the tubular portion forms, when the parts of the inhaler are assembled together, the upper part of the capsule chamber and has a slightly concave surface for facilitating the rotation of a capsule. At the opening of the inhalation passage of the tubular portion there is a grating, suitably dimensioned to optimize the air/powdered substance ratio. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     One embodiment of the invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which: 
     FIG. 1 is an axial section of the mouth-piece of an inhaler formed as an embodiment of the invention; 
     FIG. 2 is a plan view of the mouth-piece shown in FIG. 1; 
     FIG. 3 is a side view of three elements forming a spring-lock device for holding the mouth-piece and a body portion of the inhaler in operating relationship; 
     FIG. 4 is a bottom view of the body portion of the inhaler; 
     FIG. 5 is an axial section of the body portion of the inhaler taken on the line 5--5 of FIG. 4; 
     FIG. 6 is a plan view of the body portion of the inhaler; 
     FIG. 7 is a side view of the body portion of the inhaler taken on the line 9--9 of FIG. 5; 
     FIG. 8 is a sectional view of a push button which is attached to the body portion of the FIGS. 4 through 7; 
     FIG. 9 is an end view taken on the line 9--9 of the push button of FIG. 8; 
     FIG. 10 is a sectional view taken on the line 10--10 of FIG. 9; 
     FIG. 11 is an axial sectional view of an assembled inhaler; 
     FIG. 12 is an axial partially sectioned view similar to that of FIG. 11, showing the inhaler with a cap in position; and 
     FIG. 13 is a side view, taken on the line 13--13 of FIG. 12 of the inhaler with the cap in position of FIG. 12. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings, the inhaler shown comprises a body portion 21 and a mouth-piece 22. The mouth-piece 22 has an ellipsoidal tubular portion, with walls 36 and inhalation passage 35, and an enlarged basal end 23 which engages the upper face 33 of the body portion 21. The mouth-piece 22 is connected to the body portion 21 by means of a pivot pin 3, projecting from the basal end 23 of the mouth-piece 22, which fits into a hole 13 in the body portion 21. The pivot pin 3 and hole 13 are aligned with one another when the mouth-piece 22 and body portion 21 are assembled and have a common pivotpin axis. The pivot pin 3 and hole 13 are each respectively disposed eccentrically to the longitudinal axis of the mouth-piece 22 and body portion 21. 
     At the end of the pivot pin 3 is a lateral projection 3al The hole 13 has a lateral enlargement 13a and at the lower end thereof has an enlarged annular section 13b. The lateral projection 3a of the pivot pin 3 passes down the lateral part 13a of the hole 13 upon insertion of the pin 3 into the hole 13 when the pivot pin 3 and hole 13 are in register. Upon relative rotation of the body portion 21 and the mouth-piece 22, this lateral projection 3a is moved out of register with the lateral part 13a of the hole 13 and into engagement with the shoulders at the end thereof formed by the enlargement 13b. 
     The position of the lateral projection 3a and the lateral part 13a is, in each case, such that the mouth-piece 22 and body portion 21 can be relatively revolved about the pivot-pin axis of the pivot pin 3 and hole 13 between an operating position in which the basal end 23 of the mouth-piece 22 is in register with the upper face 33 of the body portion 21, and a loading position where a chamber 10 in the body portion 21 is exposed without bringing the lateral portion 3a of the pivot pin 3 into register with the lateral part 13a of the hole 13 so that, in use of the inhaler, the two portions 21 and 22 can remain fixed to one another, but the two portions 21,22 may be separated from one another entirely if desired by relative revolution of the two portions to bring the cooperating projections 3a and part 13a into register. 
     The body portion 21 of the inhaler is formed, as mentioned above, with a recess 10 having a circular cross section, in the lower wall of which there is an elongated recess 9 which has substantially the same shape as a conventional medicament capsule, as can be seen clearly in FIG. 6. There are two narrow recesses 12, 12&#39; in the upper face 33 of the body portion 21. These recesses 12, 12&#39; communicate tangentially with the recess 10, as can be clearly seen in FIG. 6. When the mouth-piece 22 and the body portion 21 of the inhaler are assembled in operating position, the lower face 34 of the basal portion 23 of the mouth-piece 22 closes the recess 10 to define a capsule spinning chamber 10. Similarly, the recesses 12, 12&#39; are closed by the lower face 34 of the basal portion 23 to form air inlets or passages 12, 12&#39; to the capsule spinning chamber 10. In other words, combining the mouth-piece 22 and the body portion 21 to form the inhaler of this invention covers the recesses 10, 12 and 12&#39; to form the chamber 10 and the air inlets 12, 12&#39;. 
     At the lower end of the inhalation passage defined by the mouth-piece 22, there is secured a grating 1 which prevents a capsule in the capsule chamber 10 from being drawn up the mouth-piece 22 upon inhalation. There is thus open communication between the inhalation passage 35 of the mouth-piece 22, the capsule chamber 10, and the air inlets 12 and 12&#39;. 
     FIG. 3 illustrates a suitable form of latching device for holding the mouth-piece 22 and body portion 21 in operating relationship. As will be seen from FIG. 1, the basal portion 23 of the mouth-piece 22 has a projection 2 on the side thereof opposite the pivot pin 3; this projection 2 is L-shaped when viewed from the right side of FIG. 1 and is obliquely disposed to the major axis 37 of the ellipsoid formed by the walls 36, as seen in phantom in FIG. 2. The projection 2 has a latching lug 2a which projects laterally. The body portion 21 has an L-shaped recess 24 which is obliquely disposed to the major axis 37 of the ellipsoidal recess 9 and has a latching slot 24a which projects laterally. The L-shaped projection 2 of the basal portion 23 of the mouth-piece 22 slides into L-shaped recess 24 in the upper part of the body portion 21 when the mouth-piece 22, viewed as in FIG. 2, is revolved clockwise around the body portion 21, viewed as in FIG. 6, and is held in position by the latching device illustrated in FIG. 3. 
     The latching device comprises a plunger 4 having a convexly curved end, a compression spring 5, and a plug 6. These elements are housed in a bore 25 in the body portion 21 which is visible in FIGS. 4 and 7. This bore 25 opens into the lower face of the L-shaped recess 24. The plunger 4 has a shoulder 4a which engages a corresponding shoulder 25a near the upper end of the bore 25 to determine the maximum amount by which the convexly curved end of the plunger 4 can project from the opening formed by the bore 25 into the L-shaped recess 24. When the mouth-piece 22 is revolved to the locked position, the lateral projection 2a extends into the latching slot 24a and displaces the plunger 4 downwardly against the action of the compression spring 5 which thus acts to lightly latch the projection 2 in place in the recess 24, thereby holding the mouth-piece 22 and body portion 21 together in the closed or operating position. 
     In line with the ends of the capsule recess 9, in the bottom of the recess 10, are located two push buttons 26 which each carry four sharpened metal pins 14 which project inwardly towards the capsule recess 9, as shown in FIG. 11-13. The body portion 21 is formed with two rectangular section galleries 7, 7&#39;, as shown in FIGS. 4 and 5, which have openings 8, 8&#39; aligned with the end of the capsule recess 9. Each push botton 26 has a pair of shoulders 15, 15&#39; which are located against the rims of an opening 8 or 8&#39; in the outer wall 38 of the body portion 21 and held in position by four biasing springs 31, 31&#39; which are mounted in respective recesses 16, 16&#39; in the push buttons 26. The inner walls 32, 32&#39; of the galleries 7, 7&#39;, between the galleries 7, 7&#39; and the capsule recess 9, are provided with four openings 11, 11&#39; aligned with the sharpened metal pins 14. 
     Pressure applied to the push buttons 26, to compress the biasing springs 31, 31&#39; which locate them in position, urges the sharpened metal pins 14 through openings 11, 11&#39; and into the capsule recess 9. When a capsule is positioned in the recess 9, it is held against movement because the recess 9 is only slightly larger than the capsule itself, and thus the sharpened metal pins 14 penetrate and perforate the two ends of the capsule, permitting the powdered medicament to pass out through these perforations after the push butttons 26 have been released. 
     As shown in FIGS. 12 and 13, the inhaler is fitted with a conventional cap 40 which covers the mouth-piece 22 and rests against the open end of the mouth-piece 22 and against the two pushbuttons 26. It is centered with respect to the 44, as is known in the art. 
     In operation of the inhaler, the mouth-piece 22 is opend in a counter-clockwise direction 45. As seen in FIGS. 2 and 6, the moth piece 22 is revolved about the hole 13 to expose the recess 10 and the capsule recess 9. A capsule is dropped into the capsule recess 9. The mouth-piece 22 and body portion 21 are then closed by clockwise revolution of the mouth-piece 22, as seen in FIG. 2, about the hole 13 in the body portion 21 until the projection 2 engages the recess 24 and the lug 2a fits into the latching slot 24a so that the projection 2 is latched in position by the plunger 4. The push bottons 26 are then depressed, either individually or together, to perforate the ends of the capsule in the capsule recess 9. 
     Administration of the powdered medicament can then take place simply by inhaling through the mouth-piece 22 which can be applied either to the mouth or to a nostril. The rush of air through the inlets 12, 12&#39; upon inhalation causes a vortex in the capsule chamber 10 due to the fact that the inlets 12 and 12&#39; are positioned substantially tangentially with respect to the circular section capsule chamber 10. The vortex in the capsule chamber 10 lifts the perforated capsule out from the capsule recess 9 and causes the capsule to spin rapidly about the longitudinal axis of the inhaler. Because the length of the capsule is slightly less than the diameter of the capsule chamber 10, there are repeated impacts between the ends of the capsule and the side wall of the chamber 10 which causes powdered medicaments from within the capsule to be drawn out through the perforations in the ends of the capsule, this being assisted by the spinning motion of the capsule itself, and the powder is entrained with the air passing through the grating 1 and along the inhalation passage 35 of mouth-piece 22. 
     Because it will be readily apparent to those skilled in the art that innumerable variations, modifications, applications, and extensions of these embodiments and principles can be made without departing from the spirit and scope of the invention, what is herein defined as such scope and is desired to be protected should be measured, and the invention should be limited, only by the following claims.