Needleless Inoculator

Abstract

A needleless injector is provided with a body portion having a chamber for receiving a vial containing a fluid material. Adjustable force applying means are positioned coaxially with the vial in order to discharge the contents thereof through a bore and into an injection head. Improved electrically operated means are provided for cocking a spring member which is released by a manually operable trigger for dispensing the fluid from the head.

Description

The aforementioned Abstract is neither intended to define the invention of the application which, of course, is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to fluid injection means but more particularly to an improved needleless injector.

2. Description of the Prior Art

The patent literature is replete with many examples of needleless injectors. Perhaps the best example of this type of device heretofore available is the structure shown in the Zimmet et al. U.S. Pat. No. 3,461,867, granted on Aug. 19, 1969. The Zimmet et al. patent teaches the use of a body member having means for supporting a vial and means coaxial with the vial for expressing the fluid therefrom. The injector is provided with means for controlling the fluid issuing from the vial under pressure. On a second and parallel axis there is also provided a chamber in fluid communication with the vial, as well as a plunger for forcing the fluid from the second chamber into a discharge head that includes still another valve. A hand operated lever is provided for loading a spring that actuates the plunger into the second chamber.

While the Zimmet et al patent does teach relatively effective means for injecting fluid without a needle, there are several shortcomings in the device. First of all, the hand operated lever for loading the plunger spring is somewhat awkward to use in that two hands are required. That is, one hand must grip and securely hold the body of the device while the other hand must be used to pivot the lever about a pin. Secondly, separate forces on two different parallel axes must be applied in order to discharge the fluid from the vial and then discharge the fluid from the head.

SUMMARY OF THE INVENTION

By way of contrast, the present invention provides a relatively simple, hand-held device that may be cocked electrically and which requires the use of only one hand for this purpose. An elongated tubular body is provided with a spring-loaded, magnetizable core member that is adapted to be inserted within an electrically energizable coil. When current is passed through the coil, a magnetic field will be induced and the core member will be axially displaced thereby while a spring loaded trigger and latch will automatically lock the core member in its displaced position. The device is then operated merely by depressing the trigger so as to free the core member from the latch. When the core member is displaced a plunger carried thereby is coaxially inserted into a vial containing the fluid. A valve that is coaxial with and downstream of the vial controls the flow of fluid therefrom to a discharge head which is also provided with a vial for metering the quantity of fluid that is to be discharged.

One embodiment of the present invention was built to operate at nominal 120 volts A.C. and delivered a volume of fluid which was adjustable from 0 to 0.6 cc's. The device is completely divorced from electrical sources when applied to the patient and thus avoids accidental electrical shocks. The power pack section is readily removable and reattachable to the head and vial support sections. The use of a solenoid type device for cocking the instrument provides inherently durable structure.

Accordingly, it is an object of the present invention to provide improved injection apparatus that does not require the use of a needle for piercing tissue.

It is another object of the present invention to provide an improved electrical cocking structure for the needleless injector comprising the present invention.

A feature of the present invention is that the vial containing fluid and the plunger for discharging the fluid are located on a common axis.

Still another feature of this invention is that the vial support section and the discharge head are readily separable and interchangeable with respect to the power pack section.

These and other objects, features and advantages of the invention will, in part, be pointed out with particularity, and will, in part, become obvious from the following more detailed description of the invention, taken in conjunction with the accompanying drawing, which forms an integral part thereof.

BRIEF DESCRIPTION OF THE DRAWING

In the various figures of the drawing like reference characters designate like parts.

In the drawings:

FIG. 1 is an elevational view, partially broken away and partially in section, illustrating the structure of the present invention;

FIG. 2 is an elevational view, partially broken away and partially in section, illustrating the injector comprising the present invention;

FIG. 3 is a longitudinal, sectional view illustrating a portion of the power pack section of the present invention;

FIG. 3A is a fragmentary, longitudinal, sectional view illustrating a constructional feature of the power pack section of this invention;

FIG. 4 is an end elevational view taken along the line 4--4 of FIG. 3;

FIG. 5 is a longitudinal, exploded view, partially broken away and partially in section, illustrating the components of the power pack section comprising this invention;

FIG. 5A is a transverse, sectional view, taken along line 5A--5A of FIG. 5;

FIG. 6 is a view in elevation of one of the components of the power pack section of the present invention;

FIG. 7 is a longitudinal, elevational view of the combined vial support section and discharge head of the present invention;

FIG. 7A is an end elevational view taken along line 7A--7A of FIG. 7;

FIG. 8 is a longitudinal, exploded view, partially broken away, illustrating internal structure of the vial support section;

FIG. 9 is a longitudinal, sectional view illustrating additional internal structure of the vial support section;

FIG. 9A and FIG. 9B are fragmentary, longitudinal views on an enlarged scale and partially in section, illustrating further details of the structure shown in FIG. 9;

FIG. 10 is an enlarged, sectional view of the discharge head comprising this invention;

FIG. 11 and FIG. 11A are end elevational views of alternative embodiments of the discharge head of this invention; and

FIG. 12 is a transverse, sectional view taken along line 12--12 of FIG. 2.

Referring now to the drawing and specifically to FIG. 1, there is shown an improved, needleless, hypodermic injector 20 comprising the present invention. The injector 20 is comprised of three basic sections. The first section is the power pack 22, the second or intermediate section is the vial support 24 while the third section is the discharge head portion 26. The power pack section 22 and the vial support section 24 are removably coupled to each other by means of a bayonet arrangement comprising radially inwardly directed pins 28 and 30 of different sizes (FIG. 3) that mate with suitably sized, shaped and located L-shaped slots 32 and 33 (FIG. 7). For purposes to be disclosed subsequently, there is also provided a guide pin 34 extending radially outward. In the embodiment illustrated the guide pin 34 is a screw that is threadably received in a tapped hole 35.

Turning now to FIGS. 3-6, it will be seen that the power pack section 22 is comprised of a tubular housing 36, which, for purposes to be disclosed hereinafter, includes an aperture 38 through one wall thereof, a pair of internal, axially spaced apart annular grooves 40, a second aperture 42 formed in one wall thereof intermediate the annular grooves 40 and an elongated, axially extending slot 44. A trigger 46 is provided that includes a recess 48 on the underside thereof at one end, a transversely extending lip 50 at the other end and a downwardly depending ear 52 intermediate the recess 48 and the lip 50. The trigger 46 is pivotally mounted within the slot 44 by means of a pin 54 that extends through a hole 56 formed in the ear 52 and a chordally directed pair of aligned holes 58 formed in the wall of the housing 36. The axis of the pin 54 is substantially parallel to the transversely extending lip 50. A blind recess 62 is formed in the wall of the housing 36 in order to receive one end of a generally radially oriented, external compression spring 64. The other end of the compression spring 64 is received in the recess 48 formed in the underside of the trigger 46. For esthetic reasons, the ends of the holes 58 may be plugged after the mounting pin 54 is inserted therethrough. Finally, the housing 36 is provided with an internal, transverse wall 66 positioned approximately at the location of the pair of holes 58. An axially extending bore 68 is formed in the transverse wall 66 for reasons which will become apparent hereinafter.

Continuing with the description of the power pack section 22, there is also provided, as shown in FIG. 5, a central, tubular core, generally designated by the reference character 70, which is located within the housing 36. The tubular core 70 is comprised of an elongated, axially extending cylindrical portion 72 terminating in a first transversely enlarged diameter portion 74. There is also provided a second enlarged diameter portion 76 as well as two additional portions 78 and 80 having relatively smaller diameters. A pair of transverse walls 82 and 83 are defined between the diametrical portions 78 and 80 and between the diametrical portions 76 and 78, respectively. The core member 70, as shown, for example, in FIG. 5, terminates at one end in a transverse wall 84 having an axially oriented bore 86 therethrough. The opposite end of the core 70 is provided with external threads 88.

A hollow, axially movable rod 90 is positioned within the core 70 and is provided with an enlarged, first head portion 92 at one end thereof. The opposite end of the rod 90 is also provided with a second head portion 94. In the embodiment illustrated the second head portion 94 is formed by a screw that is threadably received within the end of the rod 90. Thus, the rod 90 is axially slidable within and relative to the core 70 but, by virtue of the head portions 92 and 94 at its opposite ends, is captured and the axial movement thereof is limited.

A plurality of belleville washers 96 are mounted on the tubular portion 72 in abutment at one end with the diameter 74 in order to form a resilient, spring-like biasing member. A collar 97 having a single flat surface 98 formed on the periphery thereof, is loosely mounted on the tubular portion 72 in order to capture the belleville washers 96. Undercuts 100 are formed on axially opposite sides of the collar 97 and receive resilient washers 102. In the assembled condition within the housing 36, the enlarged diameter portion 76 abuts the transverse wall 66 and two retaining rings 104 that are received in the annular grooves 40, are mounted about the collar 97 proximate the axially spaced ends thereof. Thus, the collar 97 is prevented from moving axially. A radially extending pin 106 extends through the opening 42 in the housing 36 and is provided with a headed inner end 108 that bears against the flat peripheral surface 98 of the collar 97. This construction also prevents rotational movement of the collar 97. However, the core 70 is slidable in an axial direction relative to the collar 97.

An elongated compression spring 110 is positioned within the tubular rod 90 and also extends through the tubular core 70 for biasing the rod 90 with respect to the core 70. The left hand end of the compression spring 110 is provided with an internal stiffening rod 112 as shown in FIG. 5. A magnetizable cap member 114 is provided with internal threads 116 that mate with the threads 88 formed on the core member 72 in order to form an integral but separable unit. A conical seat 118 is also provided in the cap member 114 in order to receive the left hand end of the stiffening rod 112. In the assembled condition the cap member 114 bears against one of the resilient washers 102 and is telescopingly positioned within the housing 36. On the outside surface of the cap member 114 there is provided a plurality of indicia 119 which, in the embodiment illustrated, take the form of consecutive numbers. The indicia 119 are positioned along a helical path and are arranged to register through the opening 38 formed in the housing 36 so as to provide an indication of the dosage to be discharged. This setting determines the travel of member 70 when the spring pressure is released as described hereinafter. As shown in FIGS. 7 and 8, the vial supporting section 24 is comprised of a housing 120 on one end of which the bayonet slots 32 and 33 are formed. The bayonet type coupling renders it a simple matter to uncouple the vial support section 24 from the power pack section 22 when the vial V must be replaced. This construction also facilitates sterilization of the discharge head section 26. The housing 120 is further provided with an internal, annular lip 121 and a pair of diametrically opposed, axially extending slots 122 through which the contents of a vial V are visible. Internally of the housing there is provided a tubular sleeve 124 having a pair of diametrically opposed, axially extending slots 125 aligned with slots 122 and a transverse wall 126 formed at one end thereof. A threaded opening 128 is formed in the wall 126. The sleeve 124 is further provided with a relatively narrow and relatively short axially extending slot 130 near the end opposite the wall 126. The slot 130 is angularly offset from the diametrically opposed slots 122 and receives the guide pin 34 for preventing rotation of the sleeve 124. As shown in FIG. 12, the guide pin 34 does not touch the vial V which has a pierceable head end H, an axially movable integral plug P and which is positioned internally of the sleeve 124. In the assembled condition, the left hand end surface 132 of the sleeve 124 abuts the transverse wall 82 formed between the diametrical portions 78 and 80 of the member 70.

A tubular rod 134 (FIG. 9) is provided with external threads at one end thereof that mate with the threads 128 formed in the sleeve 124. A plug 136, having a fine, central bore 138, is provided with a tubular piercing member 140 that is in fluid communication with the bore 138. An elongated compression spring 137 is positioned about the tubular rod 134. One end of the spring 137 bears against the end wall 126 of the sleeve 124 while the other end of the spring 137 bears against the annular lip 121 of the housing 120. In the assembled condition, the piercing member 140 extends through the end H of the vial V in order to receive the fluid therein. At this time, it should be noted that the head portion 94 of the rod 90 bears against and axially pushes the plug P within the vial V so as to force the fluid into and through the piercing member 140 and the bore 138. The plug 136 is captured within the tubular rod 134 by means of mating threads 142 and is also provided with a sealing ring 144 that is secured in an annular groove 146 formed on the outside surface of the plug 136. The sealing ring 144 is positioned within a counterbored recess 148 formed in the left hand end of the tubular rod 134 as shown in FIG. 9.

An internal chamber or cavity 150 is provided in the tubular rod 134 so as to be in communication with the bore 138. A bore 152 is also formed in the tubular rod 134 and is in fluid communication with the cavity 150 and thus with the bore 138. A rod 154 is slidably positioned within the cavity 150 and, at one end thereof, is provided with a conical neck portion 156 on which is mounted a resilient sealing member 158. As shown in FIG. 9A, the left hand end of the neck 156 abuts the right hand end of the plug 136 and the sealing member 158 is positioned about the bore 138. At the opposite end of the rod 154, as shown in FIG. 9, there is provided a reduced diameter portion 160 that forms a transverse wall 162 in combination with the body portion 154. A compression spring 164 that normally urges the rod 154 and the sealing member 158 to the left (FIG. 9), is positioned about the reduced diameter portion 160 and extends between the transverse wall 162 of the rod 154 and the transverse end wall of the cavity 150.

The right hand end of the tubular rod 134 (FIG. 9) terminates in a first diametrical portion 166, an annular undercut 168 and a conical tip 170. The bore 152 extends through the tip 170. A first plastic washer 172, which may be made of Teflon, is positioned about the diametrical portion 166 and a resilient, elastomeric washer 174 is mounted on the undercut 168. A plastic cap member 176, which also may be made of Teflon, is slipped over the washer 174. As shown in FIG. 9B, the cap member 176 is also captured within the undercut 168. The conical tip 170 serves to capture the cap member 176 which is provided with a conically diverging bore 180. As shown in FIG. 9B, the cap member 176 extends axially beyond the conical tip 170.

The head portion 26 comprising the present invention may best be seen in FIG. 10. A housing 182 having a channel 184 formed therein is secured integrally to the housing 120 by any convenient means such as brazing or the like whereby the channel 184 is in fluid communication with the bore 152. A counterbored hole, defined by bores 186 and 188 as well as a transverse interface 190 therebetween, is formed in the housing 182 with the bore 186 being in communication with the channel 184.

A first tubular sleeve 192, having a transverse flange 194 is positioned within the housing 182 such that a sealing ring 196 is captured between the flange 194 and the transverse wall 190. The sleeve 192 is further provided with an internal chamber 198 that communicates with a fine bore 200 having a conical orifice 202. A plurality of radially extending holes 204, for example three, are formed in the sleeve 192 so as to be in communication with the chamber 198. The head end of the sleeve 192 is defined by an end portion 206 in which an undercut 208 is formed in order to receive a resilient sealing ring 210.

A piston 214 is slidably received within the sleeve 192 and includes a piston head 220. A pair of sealing rings 216 and 218 are located near the head end 220 A plug 222 is threaded into the housing 182 in order to capture a spring 224 that is arranged to bear against the head end 220 of the piston 214. Plug 222 captures O-Ring 215 and squeezes it against head end 220 and also forces sleeve 192 to squeeze O Ring 196 against wall 190 thereby sealing off the contents of sleeve 192. A sealing ring 226 is positioned within the chamber 198 about the bore 200 and adjacent the left hand end of the piston rod 214 as shown in FIG. 10. An elastomeric sleeve 228 is mounted on the outer end of the piston 192 and surrounds the conical orifice 202. It will be noted that the sleeve 228 extends axially to the left of the orifice 202 as shown for example in FIG. 10.

Alternative embodiments of the present invention are shown in FIG. 11 and FIG. 11A. Instead of providing a single, centrally located bore such as shown by reference character 200 in the first embodiment (FIG. 11), there may also be provided a plurality of bores 230 that are equally spaced apart on a common radius (FIG. 11A). In both embodiments the bores 200 or 230 are in the order of 0.003 inches diameter.

MODE OF OPERATION

Reference may be had once again to FIG. 1 for a better understanding of the means used for cocking the injector 20. There is provided a housing 232 comprised of a base member 234 and an integral, vertically extending support column 236. A bore 238 extends through the column 236 and the base member 234 and has concentrically positioned thereabout, in the vicinity of the base member 234, a coil 240 that is suitably secured in the base member 234. The coil 240 is connected in series with an electrical power source. A manual switch 242 and a conventional trigger circuit 244 for generating large pulses of current. A suitable fuse 246 may also be provided.

When the power pack section 22 of the injector 20 is inserted in the bore 238 and the switch 242 is closed, the magnetizable core 70 will be drawn downwardly as would be the armature of a solenoid. This causes the belleville washers 96 to be compressed between the axially movable diametrical portion 74 and the axially secured collar 97. Energy is thus stored in the belleville washers 96.

At the same time the spring 64 urges the trigger 46 in a counterclockwise direction (as seen in FIG. 3) about the pin 54, so that the lip 50 of the trigger 46 abuts the transverse wall 83 whereby the core 70 is secured in its loaded or cocked position. It should be noted at this time that the spring 110 normally urges the head portion 94 longitudinally to the right into coaxial engagement with the plug P of the vial V. At the same time the spring 137 longitudinally urges the sleeve 124 that contains the vial V to the left in coaxial opposition to the spring 110. The spring 164 is simultaneously urging the rod 154 to the left in the same direction as the sleeve 124 so that the sealing member 158 will prevent fluid leakage to the bore 138.

When the trigger 46 is depressed, or moved in a clockwise direction, the lip 50 is removed from the transverse wall 83, thus permitting the belleville washers 96 to drive the core member 70 to the right, moving member 124 forward thereby pushing fluid through bore 121 and through the channel 184 formed in the discharge head 26.

Upon entering the discharge head 26 the fluid traverses the radially oriented holes 204 formed in the housing 192. It should be noted at this time that while two holes 204 are shown as being diametrically opposed to each other, this is done primarily for convenience of illustration. It will be evident that more than two holes may be provided, and in fact in one embodiment of the invention there are three equally spaced apart radially extending holes 204. The fluid then enters the chamber 198 formed intermediate the tubular housing 192 and the piston 214. This action causes the piston head 220 to be moved to the right against the force of the spring 224. This action also causes the piston 214 to move axially away from the sealing member 226 to thereby open the fine bore 200 and the conical orifice 202 so that fluid may be discharged. When all of the fluid has been discharged the spring 224 returns the piston 214 back into sealing engagement with the ring 226.

There has been disclosed heretofore the best embodiment of the invention presently contemplated. However, it is to be understood that various changes and modifications may be made thereto without departing from the spirit of the invention.

Claims

What I claim as new and desire to secure by Letters Patent is:

1. A needleless injector for discharging fluid from a sealed vial having a puncturable member at one end and an axially displaceable plug at the other end, said injector comprising:

a. a power pack section;

b. a magnetizable core slidably mounted in said power pack section for axial movement between a latched position and an actuated position;

b'. means for magnetizing said core for axial movement thereof;

c. latch means for holding said core in said latched position;

d. trigger means for disengaging said latch means;

e. first spring means for positively driving said core from said latched position to said actuated position after said trigger means disengages said latch means;

f. means coaxial with said core and axially displaceable as a result of the movement thereof for axially displacing the plug in the vial to thereby displace the fluid to the vial;

g. a vial support section and a discharge head coupled to said power pack section, said vial support section being coaxial with said core and including a piercing member for puncturing the end of the vial opposite the plug; and

h. means for providing fluid communication between the vial and said discharge head.

2. The injector in accordance with claim 1 wherein said power pack section includes means for preventing rotation of said core.

3. The injector in accordance with claim 1 wherein said power pack section includes means for varying the force of said first spring means.

4. The injector in accordance with claim 3 wherein said force varying means comprises a cap rotatably mounted on said core and having a plurality of indicia that are registrable with a non-rotatable portion of said power pack section.

5. The injector in accordance with claim 1 wherein said plunger is coaxially slidable within said core and second spring means are further included for urging said plunger against the axially movable plug of the vial for displacing the fluid therein.

6. The injector in accordance with claim 1 wherein said first spring means comprises a plurality of belleville washers positioned about said core.

7. The injector in accordance with claim 1 further including means for removably coupling said vial support section and said discharge head to said power pack section.

8. The injector in accordance with claim 1 wherein said vial support section comprises a sleeve, a tubular rod coupled to said sleeve, said piercing member being tubular and integral with said rod, first valve means in said rod, a bore in said rod for providing fluid communication between said piercing member and said discharge head, and third spring means for urging said piercing member into the puncturable member of the vial.

9. The injector in accordance with claim 8 further including means for preventing relative rotation between said sleeve and said vial support section.

10. The injector in accordance with claim 1 wherein said discharge head comprises a hollow body portion, a passageway for providing fluid communication between the interior of said body portion and the vial, piston means slidable within said body portion, at least one discharge orifice in said body portion, second valve means intermediate said discharge orifice and said piston means and fourth spring means for biasing said piston means to a position normally closing said second valve means.