US2592369A - Powder inhaler - Google Patents

Description

April 8, 1952 H. H. YOUNG ET AL POWDER INHALER 2 SHEETSSHEET 1 Filed 001;. 15, 1948 INVENTORS.

fig/ozaz as 1 April 8, 1952 H. H. YOUNG ETAL 2,592,369

POWDER INHALER Filed OCt. 15, 1948 2 SHEETS-SHEET 2 1NVENTORS Patented Apr. 8, 1952 POWDER INHALER Howard H. Young, Waukegan, and Douglas A.

Loper, Hubbard Woods, 111., assignors to Abbott Laboratories, North Chicago, 111., a corporation of Illinois Application October 15, 1948, Serial No. 54,792

Our invention relates to the administration of air-borne powdered medicament and includes A among its objects and advantages an especially compact administration device containing no valves or moving parts but functioning automatia powder cartridge;

Figure 5 is an end view of the same cartridge;

Figure 6v is a side elevation of a mouthpiece attachment; and

Figure 7 is an end view of the same mouthpiece attachment.

In the embodiment of the invention selected for illustration, the one-piece plastic body includes the main barrel portion I9 having a slight taper,

the mouthpiece gripping band l2, a bulb-shaped end l4 for contact with a nostril, and a cylindrical bottom socket IE to receive the powder cartridge indicatedas a whole by the reference character l8.

The powder container is a single piece of plastic comprising an operating handle 26 having a knurled end 22, a cylindrical powder-receiving portion 24 having a substantially hemispherical bottom 26 and a fastening flange 28 having two diametrically opposite projecting lugs 30. The open end of the chamber, before filling with the powder charge indicated at 32, has a peripheral lip 34 extending up as indicated in dotted lines at 36. After the powder charge is in place the wire mesh screen 38 is set in place and the lip 36 is subjected to gentle heating and melts down substantially flush with the wire screen, leaving a structure with a smooth top and with the wir screen cemented in place.

Means are provided for introducing a gentle peripheral annular current into the powder receiver and withdrawing the same volume of air at a higher velocity along the axis of the container. For this purpose the chamber 16 is formed with an annular manifold 46, in the nature of a groove fed by a plurality of inlets 42, which extend a short distance parallel to the axis and then debouch through radial passages 44 of greater diameter than the passages 42.

6 Claims. (01. 128"-206) The effective delivery area of the groove manifold 40 is about two and a half times the cross section of the axial delivery bore 46. Air coming from the manifold tends to travel gently downward in an annular body until it reaches the surface of the mass of powder 32, where it is turned inwardly into a half torus and goes back up axially at considerably higher speed, achieving a final speed, on entering the delivery bore 46, about two and a half times as great as the speed of its original entry. The air thus generates what might be likened to a gentle water-spout and tends to pick up powder from the surface of the mass 32 a little at a time. As the charge is exhausted the natural inertia of the entering air will cause the half torus to move down and stay close to the mass of powder so that eventually practically all the powder is withdrawn.

In the size best for human-use, the body of Figure 1 is about two inches long and the delivery bore 46 has an internal diameter of one-eighth of an inch.

In such a size, with the parts of the approximate proportions shown, it is desirable to reduce the rate of withdrawing the powder charge and simultaneously dilute the air stream inhaled by the patient. We have illustrated two bleed passages 48 above the passages 44. Passages 44 and 48 all have a slight taper, but the effective minimum cross section of passages 48 is about one and a half times that of passages 44.

The air entering through passages 48 not only dilutes the powder content of the air stream but it tends to encircle the already fairly well stabilized air flow in the bore 46 with a peripheral envelope of relatively pureair.

To make sure that the screen 38 can be well seated over and against the end of the bore 46, the pocket I6 is counterbored at 50 to define a rabbet and the internal surface of the rabbet is formed with two oppositely spaced slightly eccentric arcs 52 defining very gently tapered cam surfaces against which the ears 30 can be forced into firm wedging contact. By inserting the container with the ear in the dotted line position of Figure 3 and then rotating the container clockwise as viewed in Figure 3, while pushing on it gently in an axial direction to keep the screen 38 seated against the opening in the bore 46, the container is finally anchored with the screen 38 snugly pressed into the -bottom of the socket Hi.

It not infrequently happens that an inexperienced user will occasionally blow through the apparatus instead of sucking, either because of an accidental paroxysm such as a sneeze, or out of mere curiosity. When this occurs, the air passin down the bore 46 in the wrong direction is moisture-laden, but because of the peculiar configuration of the parts, such reverse flow of moisture-laden air does not dampen the screen 38 to such an extent as to cause the apparatus to clog and function erratically.

There are several reasons for this action. First, the stream through the bore 46 entering the powder chamber tends to generate a complete torus, from which air leaves with minimum velocity by getting into the manifold 40, but in which there is a slowing down and a steep curvature in the path of flow at the other end of the torus at some such point as indicated at 53 in Figure 4. Accordingly, most of the powder that would otherwise circulate in the torus is drawn out of the stream and deposited at such a point as 53, so that the passage of a given amount of air through the device in reverse flow discharges a much smaller quantity of the powdered medicament than is picked up by the same amount of air going through in th right direction. Because the velocity in the torus adjacent the manifold 40 is also low, a little powder tends to deposit at this point also, and because of the low velocity the powder can and apparently does materially obstruct the air exit so that a much larger proportional amount of the reverse flow will exit through the passages 48 than the proportion that enters through the passages 48 in normal use.

It is not infrequently desirable to administer powdered penicillin and other powdered medicaments by inhalation per 0s. The mouthpiece 54 has a cylindrical entrance mouth at 56 having a female shape withv cam surfaces 58 of slight eccentricity to receive and grip the corresponding cam surfaces constituting the band l2. Beyond the receiving end we prefer to taper the passage in one direction only so that the opening into the mouth is a narrow slit 60.

The structure affords a convenient variation in the speed of ingestion to suit the needs or whims of the patient. If one of the passages 44 is covered with a finger tip or plugged with a toothpick, the amount of medicament the air Will carry is approximately cut in half. Covering or plugging one of the passages 48 will increase the concentration of medicament substantially and covering both of them will add a further substantial increment in the concentration.

There are many brands and varieties of plastic material on the market. Those suitable for such parts as the body I 0, cartridge I8 and mouthpiece 54 have stress-strain characteristics such that when two parts, both of such material, are wedged together, there seems to be a residual reaction or resilience such that the parts spring loose accidentally during even gentle manipulation. To overcome this, we have made the contact angles of the cam surfaces I2, 52 and 58 more acute than would otherwise be expected. Specifically, the angle between the direction of relative movement and the plane of the contact surface should not exceed about five degrees, and about three and a. half degrees is the angle actually used. This angle provides a sufiicient size range to take care of size variations in question. At the same time it provides enough mechanical advantage to enable the user,by applying a normal and comfortabl'e'amount of manual .force, to strain or distort the material at the point of wedging contact to such an extent that the tendency. to snap loose almost spontaneously, is overcome.

Others may readily adapt the invention for use under various conditions of service by employing one or more of the novel features disclosed, or equivalents thereof. As at present advised with respect to the apparent scope of our invention, we desire to claim the following subject matter.

We claim:

1. An inhaler comprising, in combination, a body having a longitudinal axial bore; one end of said body being shaped for contact with a natural body orifice; a pocket in the opposite end of said body communicating with said longitudinal bore; an annular manifold in the bottom of said pocket encircling and spaced from said bore; inlets for admitting atmospheric air to said manifold, said inlets comprising a plurality of passages leading from said manifold axially away from said pocket and then radially out of said body; means for retaining a charge of powdered medicament in said pocket exposed to said manifold and to said bore; the effective area of said manifold for delivering air in the direction of said charge being about two and a half times as great as, the cross sectional area of said bore; said body having radial passages extending in to an intermediate point in said bore for peripheral dilution of the stream sucked in through said bore by the patient; said power-holding means comprising a tubular cup, shaped to fit loosely in said pocket; a wire mesh screen over the open end of said cup; a flange adjacent the bottom of said cup; radially acting cam surfaces on said flange and body, having a wedging action to anchor said cup in said pocket with said screen pressed against the bottom OI said pocket; and an axially extending portion beyond said fiange constituting a handle for insertion and anchoring of said container.

2. An inhaler comprising, combination: a body having a longitudinal bore;. one end of said body being shaped for contact'with a natural body orifice; a pocket in the opposite end of said body communicating with said longitudinal bore; an annular manifold in the bottom of said pocket encircling and spaced from said bore; inlet means for admitting atmospheric air to said manifold, said inlet means leading from said manifold axially away from said pocket and then out of said body; means for retaining a charge of powdered medicament in said pocket exposed to said manifold and to said bore; the efiective area of said manifold for delivering air in the direction of said charge being materially greater than the cross sectional area of said bore; said body having inlet means at an intermediate point in said bore for dilution of the stream sucked in through said bore by the patient; said powder-holding means comprising a tubular cup shaped to fit loosely in said pocket; a wire mesh screen over the open end of said cup; and means for anchoring said cup in said pocket with said screen against the bottom of said pocket.

3. An inhaler comprising, in combination: a body having a longitudinal bore; one end of said body being shaped for contact with a natural body orifice; a pocket in the opposite end of said body communicating with said longitudinal bore; an annular manifold in the bottom of said pocket encircling and spaced from said bore; inlet means for admitting atmospheric air to said manifold; means for retaining a charge of powdered medicament in said pocket exposed to said manifold .and to said bore; the effective area of said'mani- 'fold for delivering air in the direction of said charge being materially greater than the cross sectional area of said bore.

4. An inhaler comprising, in combination: a body having a bore; one outlet end of said bore opening through a body portion shaped for contact with a natural body orifice; said bore having an inlet end; a manifold in said body encircling and spaced from said bore; inlet means for admitting atmospheric air to said manifold; and means for confining a charge of powdered medicament adjacent the inlet end of said bore and exposed to said manifold and to said bore, whereby air moving from said manifold to said bore generates a half torus in contact with said charge and moves radially inward over the face of said charge, said torus tending to follow said charge and move down into continued contact with said charge as withdrawal of powder lowers the level of the charge.

5. An inhaler according to claim 4 in which said bore has a cross section materially smaller than the delivery area of said manifold, whereby said half torus tends to have a small high-velocity inner core moving away from said charge, and a large low-velocity outer portion moving toward said charge.

6. An inhaler comprising, in combination: a body having a bore therethrough; an end of said body being shaped for contact with a natural body orifice; a pocket in the opposite end of said body communicating with said bore; an annular manifold in the bottom of said pocket; inlet HOWARD H. YOUNG. DOUGLAS A. LOPER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 576,437 Elliott Feb. 2, 1897 1,445,068 Brown Feb. 13, 1923 2,328,246 Albion Aug. 31, 1943 2,470,296 Fields May 17, 1949 2,478,715 Schmitt Aug. 9, 1949 FOREIGN PATENTS Number Country Date 10,765 Great Britain 1889

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