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US3055362A - Hypodermic injection apparatus - Google Patents

️Tue Sep 25 1962

Sept. 25, 1962 J. w. H. UYTENBOGAART f 3,055,362

A 4 HYPODERMIC INJECTION APPARATUS Filed May 16, 1956 3 Sheets-Sheet 1 I ATTORNEYS Sept. 25, 1962 1. w. H. UYTl-:NBOGAART 3,055,362

HYPODERMIC INJECTION APPARATUS Filed May 16, 1956 3 Sheets-Sheet 2 l INVENTOR g Jvhuunzs /Y/l Vgmggaar Y kw, 5M MKM ATTORNEYS Sept. 25, 1962 J. w. H. UYTENBOGAART 3,055,362

HYPQDERMIC INJECTION APPARATUS 3 Sheets-Sheet 3 Filed May 16, 1956 Netherlands, assigner to Auguste Reoseboom, New Yorlk,N.Y.

Filed May 16, 1956, Ser. No. 585,284 8 (liaims. (Cl. 12S--218) This invention relates to a structurally and function- `ally improved hypodermic injection device which, according to certain aspects, will embrace alternative and/or improved structure over lthat disclosed in my prior application for United States Letters Patent, Serial No. 410,662, filed on February 16, 1954, now Patent No. 2,960,087.

By means of the present teachings, ian apparatus is furnished which may readily be loaded, discharged and reloaded, the entire cycle being accomplished by a power mechanism which may be repeatedly operated, either by `the attending physician or the patient. Moreover, in the discharge phase of the operation, it will be feasible for `the operator to secure an automatic functioning of the parts under which needle penetration and aspiration will initially occur. Thereupon, the cycle will be automatically interrupted to enable a user to determine whether the needle has lodged in a vein.

After this has been determined, the functioning of the apparatus may be re-initiated to assure of a discharge of medicament through the lumen of the needle and an `automatic withdrawal of the latter from the tissues. That discharge may be controlled so that a complete or an elected fractional dosage of medicament is injected.

Moreover, by the present teachings, a mechanism is provided in which the parts may be set by the user to dispense with any aspirating function. Under these circumstance-s, the discharge phase of the mechanism will embrace needle penetration of the epidermis and underlying tissue, a discharge of the medicament upon the needle having reached a proper depth and an automatic withdrawal of the needle from the tissue, all in response to a single actuation of the triggering mechanism.

Thereupon, an operator may open the apparatus and remove the spent ampule and used needle therefrom; these being replaced by 'a fresh ampule-needle unit. Regardless of the manner in which the apparatus is actuated, the patient will experience only a minimum amount of pain and the injection will be achieved with maximum efficiency.

Among other objects of the invention are those of furnishing =a device of this type which will include relatively few parts, each individually simple and rugged in construction; those parts being capable of ready assemblage to furnish a unitary apparatus functioning over long periods of time with freedom from all difficulties. As part of the assembly, a medicament-containing ampule assembly will be included which will have novel and desirable characteristics.

With these and other objects in mind, reference is had to the attached sheet-s of drawings illustrating one practical embodiment of the invention and in which:

FIG. l is an edge view of the apparatus;

FIG. 2 is a side elevation thereof;

FIG. 3 is a rear view of the unit;

FIG. 4 is a front view of the same;

FIG. 5 is a fragmentary sectional elevation of the rear portion of the apparatus with certain of the parts removed or broken away to disclose underlying elements.

FIG. 6 is a sectional plan view taken along the line 6-6 in the direction of the arrows as indicated in FIG. 5,

FIG. 7 is a sectional side view taken along the line 7-7 in the direction of the arrows as shown in FIG. 1;

aten

FIG. 8 is a sectional plan view in enlarged scale and showing the operation of loading the unit;

FIGS. 9 and 10 lare transverse sectional views taken along the lines 9-9 and 10--10 respectively in the direction of the arrows as indicated in FIG. 8;

FIG. 11 shows the position `assumed by the parts during the discharge of medicament;

FIG. l2 is a partly sectional side View of the coupling mechanism whereby fractional dosages may be achieved in addition to permitting of an aspirating function; and

FIG. 13 is a side elevation of certain of `the parts as shown in FIG. 12.

Referring primarily to FIGS. 1 and 2, the

numeral

15 indicates a casing preferably formed of metal and in line with an upper edge of which an

injection tube

16 is secured. The latter provides adjacent its outer end a nose or

contact portion

17 which may be formed of a material other than metal `and has its surface ridged. At a point adjacent the outer end of this tube,

openings

18 are formed therein. The lower portion of

casing

15, as viewed in FIG. 2, supports on its `forward face a

cap

19. Extending from its rear face is the actuating

head

20 of `a valve member positioned within

casing

15.

A control or trigger mechanism terminates in a

head

21 extending beyond the rear of

casing

15 and providing a shiftable actuator. This head is connected to a stem provided with a notch 22 (FIG. 7). A safety is furnished by conveniently employing a

plate member

23 pivotally supported as at 24 on the rear face of

casing

15 and provided with an opening, the edge of which may enter notch 22 to thereby obstruct an inward shifting of

head

21. As especially shown in FIG. 5,

plate

23 carries a

pawl

27 in the form of a spring. This engages with the teeth of an

annular ratchet

28. These teeth 'are also engaged by a

holding pawl

29 having its end secured against movement with respect to

casing

15. Therefore, a retrograde movement of the ratchet around

pivot pin

30 is prevented. A

plate

31 is attached to the ratchet conveniently by

bolts

32. This plate may carry

suitable indicia

34 capable of being registered with an

index mark

35 associated with the face of the casing.

Thus, it is apparent :that if

plate

23 occupies a position at which one end of its

slot

26 is engaged by the shank or stem of

screw

25, that plate will rest within notch 22 of the trigger element. Now, when

plate

23 is shifted around

pivot

24 to a point where the stem of

element

25 abuts the opposite end of

slot

26,

pawl

27 engaging one of the

teeth

28 of the ratchet will shift the latter around its

30. A return movement will be prevented by means of

pawl

29. So shifted,

plate

31 will be rotated to register a'graduation

lof indicia

34 with

mark

35 which indicates that the plate has been advanced, for example, the distance of one pawl tooth.

4Attention is next invited to FIG. 7 in which it will be seen that intervening

cap

19 and

actuator

20, a space is provided within

casing

15. Within this space, a

cartridge

36 is disposed. That cartridge may embrace a small flask containing liquid Freon. a certain :amount of which may have been converted to a gas. The

flask

36 supports la Sealing cap or extension 37, terminating in a pierceable diaphragm portion. A valve is provided by employing a 'body 38 which is threaded to cooper-.ate with threads formed in

casing

15. This body carries an O-

ring

49 having face contact with the adjacent cavity surface when body 38 is fully projected in an inward direction. As will be understood in connection with the

flask

36, when the diaphragm of the latter is punctured, Freon gas escapes therefrom and expands thereby reducing the internal pressure within the flask. This results in more liquid within the latter converting into gas to bring the pressure up to substantially the original value. This operation may be continued until all of the liquid is exhausted. Thereupon, the pressure of the Freon gas diminishes. Obviously, the ask should be mounted in a manner such that liquid Freon does not directly discharge therefrom under normal manipulation of the parts.

Body 38 is affixed to

actuator

20 and has a pointed extension which serves to perforate the end of tip 37 and to cooperate with the thus formed opening and adjacent casing surfaces as a valve. Extending from part 38, a passage 39 is provided which communicates with a bore 40. The stem supporting

actuating head

21 is continued at 41 within bore 40. A spring 42 within this bore serves to normally maintain this stem in a projected position. A passage 43 extends from bore 40 to a

bore

44 in line with

injection tube

16.

Bore

44 is enlarged adjacent its forward end to provide a

cylinder portion

45. Within the latter, the rear end of a

piston assembly

46 is disposed. A

spring

47 of the contraction type has one of its ends secured to this assembly. Its opposite end is attached to an anchoring unit 48 adjacent the rear end of

casing

15.

Suitable packing such .as vO-

rings

49 may be associated with the several parts to prevent leakage of fluid under pressure into the outer atmosphere. These packings also serve in association with stem 41 as a valve to control the ow of liuid from passage 39 to passage 43. It will be observed, having in mind the proportions of stem 41 and the arrangement of the packing, that a balanced cone dition will prevail, such that the operator will not have to overcome pressures when desiring to project the

actuator

21. Rather, with the shifting of

plate

23 to a point where it does not extend into notch 22, merely spring 42 will urge stem 41 in an outward direction. As the stem shifts to compress this spring, gas will of course be free to flow past valve 38 to the

bore

44 if the actuating head or

part

20 of that valve 38 has been shifted to retract the parts to permit an escape of fluid from

flask

36. The packing 49 in association with

piston portion

46 also serves to prevent a seepage of fluid under pressure past that piston. As illustrated in FIG. 7, a spring-pressed

detent

50 may bear against the rear face of

plate

23 to normally retain the latter in a position where a shifting of stem 41 is prevented.

Medicament is dispensed by the present apparatus by means of an ampule-needle assembly, a preferred form of which is illustrated in its initial condition in FIG. 8. It will be seen that the `ampule conveniently involves a

transparent tube

51 of glass which has its forward end reduced to define a

flange

52 beyond which a

neck portion

53 extends. This neck portion terminates in a bead or lip 54. The bore of the neck is closed by a stopper having its

plug

55 extending into the same. The head 56 of this stopper overlies the forward face of lbead or lip 54. Formed centrally of the head 56 an

extension

57 may be provided integral with the material of the stopper. A double-pointed

cannula

58 has secured to it, at a location short of its inner end, a

hub

59. This hub is enlarged to provide a rear portion 60 which has a diameter such that it may slidably receive the head 56 of the stopper as well as the bead 54. Its length should be such that its inner edge will lie immediately adjacent shoulder or

ange

52 when the hub is fully seated. At points short of this inner edge, hub portion 60 is formed with slits defining tongues or

pawls

61. The hub being made of metal and these tongues being biased to have their free ends tend to occupy a space within hub portion 60, it follows that with these ends extending in the direction of

hub portion

59, they may cam against and override bead 54. Their length being properly proportioned, such overriding will occur when

neck

53 is substantially completely ensleeved within hub portion 60. As they are moved in this manner, it is apparent the pawls or tongues will spring to positions to the rear of bead 54 l as shown in FIG. 11 and thus prevent a detachment of the hub and needle from the ampule.

The rear end of the

ampule

51 is closed by a

stopper

62. Similarly, to stopper 55-56, this stopper may be formed of natural or synthetic rubber. It has a diameter slightly less than that of the bore of

body

51. Adjacent its forward end, it is provided with a sealing ring by forming it with an

annular ridge

63 which in section may be rounded or V-shaped. The diameter of this ring is-in uncompressed conditi0n-slightly greater than the bore of

ampule

51. The rear face of

stopper

62 is interrupted by slits 64 which when this Zone of the stopper is expanded, may be V-shaped. Its central portion is recessed as especially shown in FIG. ll. Between

stoppers

55 and 62, a body of

medicament

65 is confined within .

ampule

51. Finally, with reference to the structure of this assembly, it will be noted that the outer zone of the needle extending beyond

hub portion

59 is protected by an enclosing sheath 66 of plastic or other suitable material. The base of this sheath is expanded around

hub portion

59 in sealing contact therewith to maintain the sterility of the needle.

This unit comes to the physician or ultimate user with the

ampule

51 filled with

medicament

65; the body of medicament being sealed against contact with the air by the Stoppers at the opposite ends. The rear portion of

stopper

62 extends slightly beyond the rear edge of ampule 51 (FIG. 8). The inner end of

needle

58 is embedded within

stopper

55 and thus maintained in sterile condition. The user, by gripping sheath 66 adjacent the

hub portion

59 is able to push that hub portion to a point where

pawls

61 override bead 54 and lock behind the same. With such movement of the parts, the inner needle end is caused to penetrate the diaphragm or remaining portion of

plug

55 so that this end is immersed within the medicament Aat a point immediately beyond the inner end of

stopper plug

55. With this movement of the parts, the flange intervening

hub portions

59 and 60 will bear against the head 56 of the stopper and slightly compress the same. Therefore, that head will exert a slight tension on the hub assuring that the free ends of the pawls will remain in fixed engagement with the bead 54 or its equivalent. Simultaneously, the projecting

portion

57 of the stopper will enter the interior of

hub part

59. Under these circumstances, it will be seen that the needle will be iirmly mounted against all undesired movements with respect to the

ampule

51. Before releasing the sheath 66, the operator may impart to the base portion of the same a slight twisting movement. This will free the inner face of the sheath from

hub portion

59 so that a subsequent pull on the sheath will unseat the latter.

In the embodiment under consideration, it will be observed that

piston

46 is formed with a

groove

68 adjacent its forward end. Secured to the forward face of casing 15 by a

bolt

70 is a catch plate 69 (FIGS. 1 and 2). The latter is shiftable transversely of the longitudinal axis of the apparatus, and with the removal of the

injection tube

16, will partially overlap the opening thus exposed. Therefore, if

piston

46 is moved to a position where the

groove

68 is immediately in line with the forward face of

casing

15, the catch may be swung around its pivot 7i) to enter that groove. Under these circumstances, the piston will be maintained in projected position.

By means of the present teachings, it is feasible to operate the apparatus so that only a portion of the

medicament dosage

65 will be injected. For example, assuming that

ampule

51 contains one cubic centimeter of the liquid, the parts may be related so that only onequarter, one-half, or three-quarters of a cubic centimeter will be discharged through the lumen of

needle

58. Of course, if no adjustment or restraint is resorted to, then the entire charge of one cubic centimeter will be dispensed. To obtain this result, the following structure may be employed:

Piston

46 may be reduced adjacent its forward end to be encircled by a

sleeve

71. In turn encircling that sleeve is a

second sleeve

72. These provide an extension of the piston. The latter, as especially shown in FIG. 8, is conveniently formed with a series of

notches

73 axially spaced from each other and connected by a

slot

74. Adjacent thereto and in line with these notches are

markings

75 which may, for example, read 1%1, 1/2, 5%1," and "1 cc. A pin or

bolt

76 is carried by

sleeve

71 and has a head of an area such that it may ride selectively into one of the

notches

73 through the

slot

74. As will be understood, with

76 in the notch designated as l cc. and as shown in FIG. 8,

sleeve

72 Will be retracted to a maximum extent. Depending upon the

notch

73, within which

bolt

76 is disposed to the rear of the first-named notch,

sleeve

72 will be increasingly projected with respect to the body of

piston

46 and

sleeve

71. By exerting a pull on

piston

46, it may be projected to permit

plate

69 to enter

groove

68. Thereupon, the desired adjustment may be made, after which catch 69 will be released. With such release,

piston

46, under the retracting influence exerted by

spring

47, will be drawn back into the bore of body until the parts finally assume the positions shown in FIGS. 7 and 8. Before departing from a consideration of this particular structure, it will be observed as especially shown in FIGS. 8 and l2, that the forward end of

sleeve

72 extends materially beyond the adjacent end of

sleeve

71 and presents an inwardly tapered

surface

77 terminating in a

shoulder

78 spaced from the edge of

sleeve

71.

Disposed for movement within the

injection tube

16 is an

ampule holder

79 in the form of a cylinder having slitted

side portions

88.

Spring arms

81 are secured adjacent their .forward ends to the inner face of the

holder

79 and have inwardly bent portions which, due to the resiliency of these arms, extend into the bore of the holder. The rear ends of

arms

81 terminate in pawl or

hook portions

82. The latter extends to the rear of the

holder

79. When an

ampule

51 is Within that holder, the outer face of the former bears against the inner edge portions of

arms

81 and swings the

portions

82 thereof outwardly so that they occupy a position spaced from each other a distance equal to the diameter of

shoulder

78.

Piston

46 is continued in the form of a

stem

83 of reduced diameter. That stem is encircled by the extension provided by

cylinder

72. The end of the stem is bored. It receives a

post

85 which mounts a collar 86 at a point short of its outer end. Beyond this collar, a

head portion

87 defines the forward end of the post. 'Ihis head portion is conveniently in the form of a truncated cone and conforms generally to the interior recess provided in the rear surface of

stopper

62 with the notches 64 in expanded condition. This

post

85 provides an ampule plunger. It is secured to but has lost motion with respect to stem 83. To connect the parts, land as shown in FIGS. ll and l2, post l85 is formed with a

slot

88. A

89 extends transversely through this slot and is mounted by

stem

83.

The rear end of the

ampule holder

79 is reduced as at 90 to provide a sleeve (FIG. 13) portion slidably encircling

stem

83. This -sleeve is formed With a

slot

91 through which the end of

89 extends. Encircling sleeve portion '90 is a

second sleeve

92. The latter is conveniently formed with an outstanding and knurled ange '93 so that it may readily be gripped and turned by the lingers of an operator. By means of a pin and

slot coupling

94, between these elements, relative rotation is limited,

Sleeve

92 is formed with a U-shaped slot, one

arm

95 of which terminates short of

flange

93. The other arm. 196 extends through

flange

93 to the edge of the

sleeve

92. A

spring

97 has one of its ends attached to the rear end of

sleeve

98. Its opposite end is secured to

sleeve

92. This spring tends to maintain

arm

96 of the slot in registry with the

slot

91 of

sleeve

90 so that

89 may ride Within these slots. However, with

89 disposed adjacent the base of the U-shaped slot,

sleeve

92 may be turned against the resistance of

spring

97 so as to register

89 with

arm

95 in the manner shown in FIG. 13 where that pin is illustrated adjacent the end of such arm.

The windows or

sight openings

18 are normally obstructed by a

ring

98 which is slidably mounted within the bore of

injection tube

16, as in FIG. ll. -This ring is provided adjacent its inner end with a

flange

99 which defines a diameter greater than that of

hub portion

68 but less than the maximum diameter of

ampule

51. A

spring

100 is interposed between this ange and the forward end of

tube

16, and thus maintains

ring

98 in the position shown in FIG. 7 unless it is deliberately shifted.

Tube

16 is provided with an

opening

101. A spring arm 182 has its rear end secured to the base of

tube

16 and extends adjacent the outer surface of that unit. At its opposite end, a pawl or latch 103 is affixed .tot this arm and projects through

opening

101 into the bore of the

tube

16.

In using the apparatus,

cap

19 is removed. A

flask

36 is introduced into the exposed bore so that the diaphragm portion at the outer end of tip 37 is adjacent the point of valve 38. That valve, by its actuator 2t), should be shifted to fully projected or closed position. With

cap

19 reapplied to its threads and tightened to fully seated position, it will cause

flask

36 to be projected so that point or Valve 38 will penetrate the diaphragm of its tip. Conveniently at this time, dial 31 is shifted to a position where its Zero indicia mark is in registry with

line

35. During this operation, the safety provided by

plate

23 or functionally equivalent structure will, of course, be maintained in a position where the trigger or actuator of the assembly may not be shifted.

Tube

16 is now removed to expose the

ampule carrier

79. An ampule-needle assembly as shown in FIG. 8 is introduced into the carrier so that the rear edge of

tube

51 bears against the shoulder intervening the

carrier

79 and its reduced

portion

90. Under these circumstances,

head

87 will bear in engagement with the surfaces of the cavity in the rear face of

stopper

62. Therefore, the rear part of this piston stopper will be expanded as shown in FIG. 8. After the introduction of the ampule into the holder, the user will shift hub 60 rearwardly with respect to

neck portion

53. This wil-l result in a locking of the needle assembly against removal or substantial movement with respect to the ampule body and will also cause the inner end of the needle to penetrate the diaphragm portion of

stopper plug

55. At this time, sheath 66 may be turned with respect to

hub portion

59 so as to free it for subsequent complete removal.

It will be assumed that the full dosage of the

medicament body

65 is to be injected. Also, it Will be assumed that an aspirating action is to be achieved. In the latter connection, it will be necessary to elect relative movements of sleeves and 92 so that

89 will lie Within the leg of the U-shaped slot in the latter sleeve. It is to be noted, regardless of the type of injection which is to be given, that with the complete introduction of the

ampule body

51 into the

carrier

79, the rear edge of the for-mer will bear against

arms

81 to swing their catch or pawl-shaped ends 82 outwardly. Therefore, as

carrier

79 abuts sleeve 72 (see FIG. ll), the

pawls

82 will interlock with

shoulder

78 to couple the parts.

Tube

16 is now again mounted on

body

15 and the parts will be disposed in the positions shown in FIG. 7, taken in con junction with FIG. l1, after sheath 66 is Withdrawn through the outer opening of

nose portion

17.

The site of injection having been selected the safety provided by

plate

23 will have been shifted.

Nose piece

17 will be brought into iirm contact with the epidermis at the desired zone. Prior to this, valve actuator 28' will have been turned so as to retract the point of `the valve from the end of tip 37 and to unseat the plug portion 38 of its body from the adjacent cavity surface. Accordingly, if liquid Freon is used within flask or

cylinder

36, that material will convert to gas under pressure and flow through passage 39 into the bore 40. Within that bore it will act with equal force upon both of the rings or

packings

49 associated with stem 41 at points to opposite sides of the exit end of passage 39. Therefore, an operator will merely have to overcome the force of `spring 42 to project

actuator

21.

With such projection, communication will be established between passages 39 and 43. Therefore, fluid under pressure Will flow through

bore

44 into

cylinder

45 and act

yagainst piston

46. That piston will now be rapidly projected. With such projection,

needle

58 will plunge into the tissues to the desired depth which will correspond to the length of the needle exposed `beyond

nose portion

17 after hub portion 60 has engaged the restricted end of

tube

16. Coincident with this projection,

ring

98 will be projected against the action of spring S to move `beyond

opening

18. Also, catch 103 will have latched against the rear edge of

carrier

79 to prevent its retraction.

It is of course understood that in this stroke, the coupling between the

carrier

79 and

piston

46 is furnished incident to pin S9 bearing against the forward end of

arm

95 of the U-shaped slot. The parts will remain in this fully projected position as long as the

actuator head

21 is maintained in depressed condition. Upon the release of this actuator, the fluid under pressure within

cylinder

45 and bore 44 will be free to drop to yatmospheric pressure because the packing 49 adjacent the forward end of stem 41 will have moved to the rear of passage 43 as shown in FIG. 7. Under these circumstances, the compressed fluid may escape through the vent opening provided at the forward end of

bore

46.

When this occurs,

spring

47 will retract

89 until that pin bottoms in

slot

88. Thereupon, post 85 will retract thereby retracting

piston

62. As a result of this functioning, it is obvious that if the needle be closed by tissues preventing aspiration, the apparatus will still function because

sleeve

92 will rotate in any event `during this phase of the operative cycle. Therefore, that cycle may `be continued through to termination even with the lumen of the needle blocked. Normally, however, with the rearward movement of

stopper

62, suction will be exerted through the lumen of

needle

58. I-f the outer point of that needle be lodged in a vein, then this will be evident by blood flowing from the inner end -of the needle.

ampule

51 is transparent and

openings

18 are unobstructed. Therefore, by looking through the latter, an observer will be able to determine whether blood is being discharged by the inner needle end.

As will `be apparent, the retraction of

piston

46 by

spring

47 will be limited to the length of travel of

89 within

arm

95 of the slot in

sleeve

92. As

89 reaches a point adjacent the base of the slot,

sleeve

92 will rotate around

sleeve

90 under the influence of

spring

97. With such rotation, the pin will be aligned with

leg

96 of the U-shaped slot. Therefore, if `

actuator

21 is now again thrust inwardly, fluid under pressure will project

piston

46. No obstruction to its movement will exist because

89 is now riding within `

slots

96 and 91. The ampule is incapable of further forward movement with respect to

tube

16. Accordingly,

head

87 will shift

piston stopper

62 forwardly through the bore of the ampule. In such shifting, a substantially complete expulsion of

medicament

65 will yfollow because of the seal provided by

rib

63 and the secondary seal furnished by the trailing edge zone of

stopper

62 incident to expansion by the

head

87.

It will be understood that with the cycle of operation continuing, the coupling furnished by parts 81-82 and 77-78 will lbecome effective. Under these circum- Such flow will be visible because the body of f stances,

carrier

79 will abut

sleeve

72. As these parts move adjacent latch or catch 103, that pawl will be cammed outwardly, thus rendering it inoperative to restrain a subsequent retraction of the assembly.

With the projection of stopper or

piston

62, the entire liquid content of

ampule

51 will be injected into the patient. The piston stopper will be arrested in a zone

adjacent shoulder

52 of the ampule. Thereupon, when the operator releases

actuator

21, it will return to its initial position under the influence of spring 42. Accordingly, the fluid under pressure will again escape through the vent in ybore `40.

Spring

47 will retract the piston. Incident `to the coupling afforded by

latch portions

82 against

shoulder

78, this retraction will result in the

carrier

79 and the ampule-needle assembly being retracted to thereby withdraw the needle from the tissue.

Tube

16 may now be dismounted and the ampule withdrawn from the carrier. This will result in the detachment of

stopper

62 from

head

87; it being noted that as soon as the stopper reaches a position where its rear zone is beyond the `

ampule

51, a ready separation of the parts will occur especially in view of the slits or notches 64 incorporated in the stopper as shown in FIG. 8. With such separation, the ampule may be withdrawn `from

carrier

79. This Will release pawls S2 to allow of withdrawal of the carrier.

The spent ampule may be replaced by a fresh ampuleneedle assembly. Prior to that,

plate

23 will have been shifted to a position where it has entered notch 22 to prevent an operation of the triggering mechanism. AS will be evident, each

time plate

23 is shifted, dial 3i will be indexed. This will enable the operator to determine the number of charges remaining within the capacity of

flask

36. Accordingly, there will be no danger of failure to operate incident to the exhaustion of the source of fluid under pressure.

As is apparent, if no aspirating action is desired, then

sleeve

92 will not be manually rotated to bring

89 within

leg

91. Rather, that pin will be permitted to rest within

leg

96. Under those circumstances, an actuation of

trigger

21 will result in a bodily projection of

arnpule

51 and its

needle

53 as heretofore described. However, upon the ampule reaching a position adjacent the outer end of

tube

16, the pressure on piston-

stopper

62 will continue and that piston will project through the bore of

lampule

51. Upon releasing

actuator

21, the entire ampule and needle will be retracted into the lbody of

tube

16.

Thus, among others, the several objects of the invention as specifically aforenoted are achieved. Obviously, numerous changes and rearrangements of the parts might be resorted to without departing from the spirit of the invention as defined by the claims.

I claim:

l. A hypodermic injection apparatus including in combination a casing formed with a bore having an open outer end and an opposite end furnishing a cylinder, a source of fluid pressure, said casing providing a passage extending from said cylinder to said source, a valve movable to control the flow of fluid through said passage to said cylinder and to vent fluid from the latter, a piston slidable within said cylinder, a pin shiftable with said piston, a carrier slidable within the outer end Zone of the bore, said carrier supporting an ampule carrying a hypodermic needle at one end and having at its opposite end a stopper projectible through its bore to expel medicament through the lumen of the needle, means connecting lsaid pin with said carrier to slide the latter towards the open end of said bore as said piston is projected, means secured to said casing to arrest movement of said carrier upon the latter reaching a position adjacent said open end, means for preventing a withdrawal of said carrier from such position, a stern forming a part of said piston to couple the latter with the stopper of said ampule, means for rctracting said piston to correspondingly move the stopper connected to said stem and to cause an aspirating action within said ampule, and said stem being Isubsequently again projectible towards said open end to cause the ampule stopper to be projected through the ampule bore.

2. In an apparatus as delined in claim 1, the means connecting said pin and carrier, including an axially extending slot formed in said carrier and within which said pin is disposed to engage the slot base upon said piston being projected towards the outer end of said bore, and means functioning upon said piston retracting to remove said pin from within said slot.

3. In an apparatus as defined in claim 2, said piston retracting means comprising a spring connected to said piston and casing respectively, and said pin and slot providing for lost motion on the part of said carrier with respect to said piston upon the latter reti-acting.

4. In an apparatus as defined in claim 2, a sleeve encircling a part of said carrier, said sleeve being iformed with a further slot communicating with said first-named slot and providing during projection of said piston substantially no obstruction to movement of said pin, and a spring cooperating with said sleeve to move the latter and shift said pin from said first-named to said lastnamed slot.

5. In an apparatus as dened in claim 2, and means forming a part of said piston whereby the eiective length of the latter may be varied to correspondingly vary the working stroke of said piston.

6. In an apparatus as dened in claim 4, said piston being formed with a bore, one end of said spring being connected to the end of said bore and said spring extend ing through the latter and being connected to the casing adjacent the end surface defining said cylinder.

7. A hypodermic injection apparatus including in combination a casing formed with a bore having an open outer end and an opposite end furnishing a cylinder, a source of luid pressure, said casing providing a passage extending from said cylinder to said source, a valve movable to control the ow of fluid through said passage to said cylinder and to vent fluid from the latter, a piston slidable within said cylinder, an ampule carrier slidable within said bore and connected to move with said piston, means at the open outer end of the casing preventing an ampule supported by said carrier from being projected therethrough, a sleeve, a detachable coupling for normally securing said sleeve against movement with respect to said carrier, said coupling embracing a plurality of engageable parts mounted by said carrier and sleeve and means functioning upon an ampule being removed from Said carrier to shift said parts out of engagement and render said coupling inoperative.

8. In an apparatus as defined in

claim

7, said coupling comprising an arm mounted by said carrier, a catch coupled to said arm, a surface of said sleeve providing a keeper for said catch and said arm being shiftable, upon an ampule being removed from said carrier, to release said catch from said keeper.

References Cited in the iile of this patent UNITED STATES PATENTS 1,845,036 Busher Feb. 16, 1932 2,445,477 Folkman July 20, 1948 2,472,116

Maynes lune

7, 1949 2,505,765 Grau May 2, 1950 2,605,765 Kollsman Aug. 5, 1952 2,605,766 Uytenbogaart Aug. 5, 1952 2,645,223 Lawshe et al July 14, 1953 2,679,843 May June l, 1954 2,693,183 Lockhart Nov. 2, 1954 2,752,918 Uytenbogaart July 3, 1956 2,766,755 Greene Oct. 16, 1956 FOREIGN PATENTS 505,931 France May 17, 1920