CA1075102A

CA1075102A - Automatic injecting apparatus

Info

Publication number: CA1075102A
Application number: CA297,651A
Authority: CA
Inventors: Carl W. Walden
Original assignee: Agri Bio Corp
Current assignee: Agri Bio Corp
Priority date: 1977-02-25
Filing date: 1978-02-24
Publication date: 1980-04-08
Also published as: ES475620A1; JPS641142B2; GB1582512A; FR2401651B3; BR7801178A; MX145685A; HU179577B; FR2401652A1; GB1582513A; GB1582515A; ES475619A1; FR2401650A1; JPS53107987A; FR2401651A1; US4108176A; NL7802109A; GB1582514A; DE2808098C2; FR2401652B3; ES475622A1

Abstract

ABSTRACT OF THE DISCLOSURE
An automatic injection device for small animals. The device comprises a work plate on which an animal to be injected can be positioned, a syringe mounted on the opposite side of the work plate from the side on which the animal to be injected is positioned during use of the device, first means for moving the syringe back and forth between a first position in which the syringe needle is entirely withdrawn on said opposite side of the work plate and a second position in which the syringe needle protrudes through an aperture in the work plate, and second means for detecting the presence of an animal to be injected in position on the work plate and for activating the first means. The first means comprises a single-action pneumatic motor and means for retaining the syringe in its second position while the mounting of the syringe is adjusted. Means for venting an accidental increase in pressure in the pneumatic supply means for indicating the completion of a preset number of injections, means permitting the quick replacement of the syringe, and a transparent valve plate permitting the user to view at least a portion of the second means are provided.

Description

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BACKGROUND OF THE INVENTION

This invention relates to a device for sequentially injecting a large number of small animals, such as chicks, duck-lings; young turkeys, and guinea fowl with a desired substance.
Such devices'are in common use, particularly in the hatchery industry, and representative examples of such devices are dis-closed, for instance, in U.S. Patents nos. 3,641,998 to Lyon et al. and 3,S64,481 to Gourlandt et al.

Devices of this general type typically comprise a work plate on which an animal to be injected can be position, a needle-type syringe (spray-type syringes may also be'used in functionally similar devices) mounted on the opposite side of the work plate from the side on which the animal to be'injected is positioned during use of the device, first means for moving the ~yringe back and for~h between a first position in which the syringe needle is entirely withdrawn on the opposite side of the work plate and a second position in which the syringe needle protrudes through an aperture in the work plate, and second means for detecting the presence of an animal to be injected in position on the work plate and for activating the first means. In the past, the first means has been an electric motor, but such motors have proved to be not entirely satisfactory for several reasons. In the first place, such mOtorS have caused some saety problems~ particularly in the wet environment of hatcheries. In the second place, while such ' machines may be portable, they can be used only in the vicinity of a source of wall current. And, in the third : : .
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place, such ~t~rs have imposed a lI~itation on t~e number of anim31s ~Lich can be injected per unit of time which is less than the rate which a skilled operator is capable of achiev mg. ~ccordingly, it has long been knc~n that it w~uld be clesirable to firld an alt ~ nate syringe actuator not suffering frc~ these clraw~acks.
It is known in the art that: sc~etimes variations of penetxation and/or closage is re~Lired, as in successive treatments or for different sizes and ages of the animals being injected, and various means æ e employed to permit such variations. However, the n~ans nc~ in use have been ~ound to be unduly c~plex, not completely accurate, and to be scmewhat lacking reliability, F~rtic~larly with respect to variatior~ in the extent of penetration.
Despite the best efforts of the user of such devices, the env;ron-me~t in which they are used is typically far ~rc~ clean, and the devices are often sub~ect to rough usage. Accordingly, it has often been necessary to open up the device to ir~ect and, if necessary, clear or repair operative components. This operation, of course, takes time ar~ is particularly irritating when, after opening up the machine, it is found that no cleaning or repairing is necessary. ~ ;
The syringe has bo be taken out, cleaned, sterilized, and replaced - one or tw~ times daily. Accordingly, it is imperative that the ~ringe be _ 3 _ ~: : ..

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easily and quickly removed and replaced, and various "quick connect" devices for attaching the syringe to the activatlng apparatus have been proposed.
All, however, have been more or less unsatisfactory due to excessively compli-cated parts, excessive operation time, and/or a tenden~y to cause bending of the syringe shafts during use.
The problems suggested in the preceding are not intended to be exhaustive, but rather are among many which tend to reduce the effectiveness of prior in~ection devices. O~her noteworthy problems may also exist; how-ever, those presented above should be sufficient to demonstrate that injection devices appearing ln the prior art have not been altogether satisfactory.
According to the invention there is provided an automatic in~ection device comprising: a work plate on which an animal to be in~ected can be positioned, said work plate having an aperture therein; a syringe mounted on the opposite side of said work plate from the side o~ which the animal to be injected is positioned during use of the device; first means for moving said syringe back and forth between a first position wherein said syringe is entire-ly withdrawn on said opposite side of said work plate and a second position wherein the needle of said syringe protrudes through the aperture in said work plate; wherein said first means comprises: a fluid motor; third means for filtering the fluid input to said fluid motor; fourth means for controll-ing the pressure of the fluid input to said fluid motor; and second means for detecting the presence of an animal to be injected in position on said work plate and for activating said first means.
It is an object of the invention to provide such a devlce which will operate safely and rellably in the wet environment of hatcheries.
It is a further object of the invention to provide such a device which is both portable and capable of operation wherever the user desires to use it.
It is yet a further object of the invention to provide such a device which is capable of being operated at a faster rate than the prior art, elec-trically powered devices.

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Other Eeatures and advantages will become apparen~ from the follow-ing detailed description of a preferred em~odiment taken in conjunction with the accompanying drawings.
In the drawings, FIGURE 1 is a perspective view of the presently preferred em~odiment of the invention, showing a chick in position for an injection.
FIGURE 2 is a side cross-sectional view taken generally along the lines 2-2 in FIGURE 1.
FIGURE 3 is a top elevational v:Lew with the cover ~roken away to expose the interior of the device.
FIGURE 4 which appears on the same sheet as FIGURE 1, is a top elevational view of the "CLEAN-VUE"TM valve plate taken generally along the line ~ in FIGURE 2.
FIGURE 5 is a sectional view taken generally along the line 5-5 in FIG~RE 2.

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FIGURE 6 is a sectional view taken yenerally along the line 6-6 in FIGURE 2.
FIGURE 7 is a sectional v;.ew taken generally along the l.ine 7-7 in FIGURE 2.
FIGURE 8 is a schematic drawing of the air logic of the embodiment shown in FIGURES 1-7.
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DEI~IIED'DESCRIPTION
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Referring now particularly to FIGURE 1, there will be seen an autL~
matic injection device ccmprising a work plate 10 on which a chick 12 is shcwn : 10 positioned rea~y f.or an injection, means 14 for detecting th~ presence of the animal to be injected in position on the work plate 10 and for actuating means (not visible in FIGURE 1) for injecting the animal~ a container 16 ~or a . liquid, such as a vaocine,-to be injected into the animal, a tube 18 for .- conducting the liquid frcm the container'16 to a syringe tnot visible in FIGURE 1), a pressure regulator oontrol 20, a pressure gauye 22~ an on-o~f switch 24, a batch counter 26, a batch reset button 27r an accumulative counter 28, an accumulator reset button 29, and a test switch 30 -the purpose of which .
: ~ ~ill be descr.ib2d hereinafter'.
.. : Turning next to FIGURE 2, there will be seen a syringe 32 of -~he :~. 20 ~eedle-variety mount~d on the'opposite side of the work plate 10 from the side ~n which the animal to be injected lS position0d duri.ng use of the device and : ~ithin a stainless st~el cabinet 34, motor means 36 for m~ving the syringe 32 ~ ~ack and forth between a ~irst position in wXich the syringe needle 38 is ; ' - 6 -'''~` ,::
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entirely withdr~wn within the cabinet 34 and a second position in ~ich the syringe needle 38 protrudes through an aperture 40 in the wo.rk plate 10, a high-pressure connector 42 (which may be connected to any convenient external source of high-pressure air, including a portable tank of high-pressur air), an air filter and pressure control mechanism 44 with a safety valve 46 u~Lich vents accidental increases in pressure in the high-pressure air, and an indicator whistle 48 the purpose of whieh will be explained hereinafter.
It will also be seen that the work plate 10 is mounted on the cabinet 34 by means of hinges 50 ar~ held in place during use of the device by a conventional latch mechanism 52. '~e motor means 36 ccn~prises a pneumatic motor which, in the preferred em~odinY~It, is an a.~r cylinder 54 connected to the air filter and pressure cont~ol meehanism 44 pneumatie circuitry described hereinafter, and an actuator 56 (shown only in FIGURE 8) which produces a ;hort, phased motion of .
the cylinder rod 58 regardless of hew long the means 14 is actuated. Such actuators are conventional elements in pne~matic circuitry, and accordingly it is not believed necessary to describe them in further detail. rrhe air .
cylinder 54 is m~unted in a motor supp~rt 5g whieh in turn is mounted on a slotted block 86 the purpose of whieh will be described hereinafter. ..
rrhe purpose of the air control and filter mechanism 44 is to make sure that the air entering the pneumatic cireuitry is clean and at the desired operating pressure regardless of the condition o~ the air entering the machine.
Its filter section has a mesh, the gauge of which is 40 microns in the presentl , preferred e~bodiment, to exclude dirt, dust, and oil frcm the system, and its : regulator section can be used to adjust incom.Lng pres~re to the desired level, -~ 25 w ich is 30 to 60 psi in the presently preferred embcdiment.

. As best seen in FIGURE 5, the s~ringe 32 is journaled for rapid trans-: la ;onal movement in an op~n-topped slot 60 in an uFwardly extending ~lock 62 _ 7 _ 1~75~

mol~ted on the ~lotted bloc;k 86. The block 62 is made of a resilient material such as a resili~t plastic~ so that the syringe 32 is snapp0d into place in the block 62 and held in place by the resiliency of the ~lock. l'he rod 58 of the air cylinder 54 is thread~d into a syringe coupling attachnent 66 which i5 slidingly supported on a block 68 mounted on the slotted block 86 as best seen in FIGURES 2 and 6. The syringe coupl.ing attachment 66 has a longitudlnal open-topped slot 70 to receive one end of a shaft 72 and a txansvexse open-topped slot 74 to receive a collar 76 caxried by the shaft 72. The open-topped slots 60 and 70 ~3gether permit the syrinye 32 an~ the sha~t 72 to be sir~ply lifted in and out of place in the block 62 and the syrinye coupling attachment 66, respectively, and the c~operation of the coll æ 76 and the trans~erse slot 74 fix the longitudinal position of the shaft 72 and the syringe 32 relative to the air cylinder 54. The shaft 72, which i5 part of the syringe plungex, is telescopically received within the syringe 32, ar~ a compression spriny 78 is carried by the shaft 72 and oonfined between the forw~rd face of the s~ringe . coupling attachment 66 and the xear face of the syringe 32.
In use, actuation of the means 14 triggers actuation of the air cylinder 54, ~hich initially causes the .rod 58, the syringe coupling attachment66, the shaft 72, and the syrLnge 32 to mo~e ~orward as a unit until the n~edle 2~ of the syringe 32 protrudes through the aper~ure 40 and into the animal by the : : desired amount At that point, a oollar 80 at the base of the s~ringe 32 oomes into abutment with the rear face of the block 62, and ~orward vement of the syringe 32~is halted. HowevP~, the rod 58, the syringe ooupling attachment 66, : and the shaft 72 cDn inue to move forward, and the shaft 72 travels tele-socpically into the butt of the syringe 32 against the force of the ooTpr ssion spring 78. Within the syringe 32, the. shaft 72 actuates a s~ringe piston to ~xpel a metered amount of liquid through the syringe needle in a n~nner kncwn : ~ ~er se. The air cylinder then reborns to its rest position under the influenoe - . . :

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o~ an internal spring (not shown), allowi~lg the spring 78 to separate the syringe coupling attachment 66 and the collar 80 o~ the syringe 32 and dra~ing the syringe 32 back to its rest position. As best seen in FIGURE 3, the rest posi.tion of the syringe 32 is determined by the c~butment of the forward face of c .
ecess in the block 62 and the rearward face of a collar 82 o.n the syr m ge 32.
The longitudinal position of the ~ir cylinder 54 and the rest position of the syringe 32 c~re c~dvantageously adjustable via the mechanism 84, best seen in FIG~RES 2 and 7. As shown therein, the ~chanism 84 co~rises the slotted block 86 to which the motor support 59, lthe block 68, and ~le block 62 are .~xedly m~unted and a pl~ality of bolts 88 which pass through the block 86 and .~re received in a support block 64. The slots in the block 86 æ e parallel to the direction of motion of the syringe 32, and by loosening the b~lts 88, slidinc ~he subc~bination c~mpris~lg the block 86, the air cylinder 54, and the syringe 2 along the surface of the support block 64, and then retigh*ening the bolts 88,he extent to which the.~eedle of the syringe 32 protrudes through the aperture 40 durLng use of the device can be adjusted.
~he transverse position of the ~;r cylinder 54 and the syringe 32 are advantageously adjustable via a sinilar slot-and-bolt mecha~isn 90 best seen in ~IGURE 3. As shcx*n therein, the mechanism 90 comprises slots 92 in the 3upport block 64 and a plurality of bolts 94 which pass through the slots 92 and~re received in the base o~ the cabinet 34. The slots 92 are perpendicular to he direction of m~tion of the syringe 32, and the mechanism 90 work in the same : ~nner as~the mechanism 84. Hcwever, it has been fo~ul~ un practice that, once : . ~e ~echanism 90 h~3 been set Ln the factcry, it is seldom necessary to, I jast it ~gaar~less the d is eub]ech3d ta seve e :base.

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1~ prevent rota~ion of the syringe 32 in the syrlnge coupling attach-ment 66, a projection 96 is provided on the block 62. In practice it has been ~nund that the syringe 32 tends ~o rotate by a f~7 degrees in the same ~irection each tLme the air cylinder 54 is activated, and the tube 18 quickly comes into contact with the pxojection 96, preventing further rotation of the syringe 32.
To aid the user of the device in varying the penetration of the needle 38 into the animals being injected, the previously mentioned test switch 30 is provided. Actuation of the test switch 30 causes air to be continuously fed into the air cylinder 54. Accordingly, the ~;r cylinder 54 extPnds, but it does not return to its normal position until the test switch 30 is deactivated. With the air cylinder 54 extended, the syringe 32 is also extended, and the user can visually deter~le whether or not its needle 38 extends through the aperture 40 by the desired am~unt and, if it does not, the amount b~ which it must be c~djusted in either directio~.
The means 14 ~or detecting the presence of the animal to be injected in position on the w~rk plate 10 and for actuating the air cylinder 54 is best seen in FIGURE 4. In the subject invention, this means c~mprises a microvalve 98 the actuator 99 of which is depresse~ by the body of the anImal to be injec-ted when it is correctly ~¦pos_tioned a , in-t the edge of a valve plate 100. ~hc mic~oval.e 98 i~

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operatively coupl~d to the air cylil~er 54 via the actuator 56, the batch counter 26, and the accumulative counter 28 by aF~ropriate pneumatic circuitry which causes the air cylir~er -to actuate and the counters to count one upon the depression of the microvalve~ The valve plate 100 is transversely adjustable via thumb ~crews 102 which pass through slots I04 in the valve plate 100 and are received in the work platP 10. The valve plate 100 is at least partially transparent, allowing the user of the device to view the microvalve 98, which is mounted on the outside of the work plate 10, and to visually determ ne whether or not it needs cleaning without remo~ing the thumb screws 102.
As previously mentioned, both a ba~ch counter 26 and an accumulative counter 28 are provided on the device. The batch counter 26 may be manually æt at any desired number, as for instance the number of chicks to be placed in eachbox after having b~en injected, and it coun~s down fram that number to zero.
The batch counter 26 is operatively connected to the whistle 48 to provide an audib]e indication of when the batch count is reached. As explained~hereina~ter in connection with the ~;r logic, when the whistle sounds, the machine autcmaticallshuts off to prevent extra units (chicks) frarn entering the batch, and the machine will operate again only when the batch reset butt~n 27 has been pushed.
m e accumulative counter 28 is designed to count up to rneasure the number of injections in any desired period, as for instance a da~, and it may be reset at zero by rneans of the accurnulator reset button 2~.
The air logic of the foregoing device is shcwn in FIGURE 8. As will be seen therein~ the c~npressed air supply is connected to the ~ir control and ; filter rnec~lanism 44, ~nd the internal pressure of the device may be adjus~ed by the pressure regulator control 20. Ihe air leaves the air control and filter m~chanism 44 and goes ~o the on-off switch 24. Frcrn there, the air branches into four separate paths. One path goes to the test switch 30, ,-.
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through a normally open path in the actuator 56, and from thcre to the air cylinder 5~. Thus, when the on-off switch 24 is turned to on and the test switch 30 is actuated, pressurized air flows di.rectly and continuously to the air cylinder 5~. The second path goes to the microvalve 98 and from there to the actuator 56, where it causes a normally closed gate in the actuator !;6 to open for a predetermined interval. The third pa~h goes to a pilot valve 106 wh;ch has two inputs and two outputs. One ou~put goes through the normally closed gate in the actuator 56 and :~rom there to the air cylinder 5~. The air cylinder 5~ is also connected to the batch counter 26 and thc accumu].ative counter 28, and actuation of the air cylinder causes the batch counter to count down one and the accumulative counter to count up one. The fourth path from the on-off switch 24 goes to the batch counter 26 and, when the batch counter 26 has counted down to zero, air is passed through the pilot valve 106 to the whistle 48, audibly signalling the end of the count, shutting down the machine until it is manually re-activated by the batch reset button 27.
Prom the foregoing description o an automatic injection device for small animals in accordance with a preferred embodiment of the inven~ion, those skilled in the art will recognize several advantages which singularly distinguish the subject invention from previously known devices. Some of those advantages are set forth below. However, while the following list of advantages is believed to be both accurate and representative, it does not purport to be exhaustive.
A particular advantage resides in the ability of the device to operate safely and reliably in the we~ environment of hatcheri.es.
A urther advantage of the device resides in its portability and its capability of operating wherever the user desires to use i~ -i.e., its independence from a fixed energy source.

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A fiIrther advantage of the device is ~he fact that it is capable of being operated at a faster rate than the prior art, electrically powered devices.
Yet a further advantage of the device is the fact that the extent of syringe needle penet~ation can be easily, accurately, and reliably ~aried.
Another ad~antage of the device is that the need for opening it up to ina~ect ~he operative component for dirt, wear, and d~mage due to other causes is lessened.
Still another advant ge of the device is that the syringe can be rem~ved and replaced with extreme rapidity and that the syringe n~ounting mecha-ni~m is extremely simple to manufacture, sturdy in use, and unli~ely to damage the syringe.
' Yet another significant aspect of the invention is that pneumatic actuation of the syringe produces an audible signal which enables an operator to facllely discern when an injection is made.
Another advantage of the device is that the necessary ad]ustments of relative parts positions are few in number and easy to make.
; Still another advantage of ~he device is that i-t insures accuracy of batch ocunts by automatlcally shutting dcwn at the end of each batch until the ~ device is reactlvated~ ~
Finally~ it should be noted that, while the present invention has been : : :
; illustrat~3d by a detailed description of a preferred e~bodi~ent thereof, it be o~Aicus to those skilled in the art tha various changes in ~orm and ; ~etail can be made therein without departlng from the true scope of the invention. For that reason, the invention must be measured by the claims ~ppended here ~ and not by the foregoing preferred e~bodiment.

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Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. An automatic injection device comprising:
(a) a work plate on which an animal to be injected can be positioned, said work plate having an aperture therein;
(b) a syringe mounted on the opposite side of said work plate from the side on which the animal to be injected is positioned during use of the device;
(c) first means for moving said syringe back and forth between a first position wherein said syringe is entirely withdrawn on said opposite side of said work plate and a second position wherein the needle of said syringe protrudes through the aperture in said work plate; wherein said first means comprises:
(1) a fluid motor;
(2) third means for filtering the fluid input to said fluid motor;
(3) fourth means for controlling the pressure of the fluid input to said fluid motor; and (d) second means for detecting the presence of an animal to be injected in position on said work plate and for activating said first means.

2. An injection device according to claim 1 wherein fifth means is provided for venting an accidental increase in the pressure of the fluid input to said fourth means.

3. A device as recited in claim 2, wherein said first means comprises means for retaining said syringe in its second position.

4. A device as recited in claim 3, comprising: sixth means for adjust-ing the amount by which the needle of said syringe protrudes through the aperture in said work plate when said syringe is in its second position.

5. A device as recited in claim 4, wherein said sixth means comprises:
a first slotted block on which said first means is carried and a plurality of bolts which pass through the slots in said first slotted block.

6. A device as recited in claim 2, comprising: sixth means for adjust-ing the amount by which the needle of said syringe protrudes through the aperture in said work plate when said syringe is in its second position.

7. A device as recited in claim 6, wherein said sixth means comprises:
a first slotted block on which said first means is carried and a plurality of bolts which pass through the slots in said first slotted block.

8. A device as recited in claim 6, comprising: seventh means for adjusting the position of said syringe in the horizontal plane and in the direction perpendicular to its direction of motion.

9. A device as recited in claim 7, wherein said seventh means comprises:
a second slotted block on which said first means is carried and a plurality of bolts which pass through the slots in said second slotted block.

10. A device as recited in claim 2, comprising: sixth means for adjust-ing the position of said syringe in the horizontal plane and in the direction perpendicular to its direction of action.

11. A device as recited in claim 10, wherein said sixth means comprises:
a first slotted block on which said first means is carried and a plurality of bolts which pass through the slots in said first slotted block.

12. A device as recited in claim 1, wherein: said second means comprise a microvalve carried on said work plate on the same side as the animal to be injected is positioned during use of the device and a housing carried by said work plate and containing said microvalve, at least a portion of said housing being transparent, whereby the user of the device can view said microvalve through said housing.

13. A device as recited in claim 12 wherein:
(e) said syringe is journaled for rapid translational movement in an open-topped slot in a block mounted on said opposite side of said work plate and (f) said syringe is connected to said first means by means compris-ing:
(i) a syringe coupling attachment which has a longitudinal open-topped slot and a transverse open-topped slot intersecting the longitudinal open-topped slot, said syringe coupling attachment being carried by said first means, and (ii) a shaft carried by said syringe and having a collar, said shaft being sized and positioned to fit into the longitudinal open-topped slot in said syringe coupling attachment and said collar being sized and position-ed to fit into the transverse open-topped slot in said syringe coupling attachment, whereby said syringe and said shaft can be simply lifted in and out of place in said block and said syringe coupling attachment, respectively.

14. A device as recited in claim 13, wherein: said block is made out of a resilient material and the width of the open-topped slot therein is less than the width of said syringe, whereby said syringe is held against vertical motion by the resiliency of said block.

15. A device as recited in claim 13, wherein: said first means com-prises means for retaining said syringe in its second position.

16. A device as recited in claim 1 wherein:
(e) said syringe is journaled for rapid translational movement in an open-topped slot in a block mounted on said opposite side of said work plate and (f) said syringe is connected to said first means by means com-prising:
(i) a syringe coupling attachment which has a longitudinal open-topped slot and a transverse open-topped slot intersecting the longitudinal open-topped slot, said syringe coupling attachment being carried by said first means and (ii) a shaft carried by said syringe and having a collar, said shaft being sized and positioned to fit into the longitudinal open-topped slot in said syringe coupling attachment and said collar being sized and positioned to fit into the transverse open-topped slot in said syringe coupling attachment, whereby said syringe and said shaft can be simply lifted in and out of place in said block and said syringe coupling attachment, respectively.

17. A device as recited in claim 16 wherein: said block is made out of a resilient material and the width of the open-topped slot therein is less than the width of said syringe, whereby said syringe is held against vertical motion by the resiliency of said block.

18. A device as recited in claim 2 comprising: sixth means for counting the number of times said first means has been actuated.

19. A device as recited in claim 18, wherein said sixth means comprises:
seventh means for counting down from a preset number to zero.

20. A device as recited in claim 19, and further comprising: means for providing an audible signal when said seventh means has reached zero.

21. A device as recited in claim 19 or 20 comprising: means for shut-ting off the device when said seventh means has reached zero.

22. A device as recited in claim 19 wherein said sixth means comprises eighth means for counting up from zero.

23. A device as recited in claim 18, wherein said sixth means comprises seventh means for counting up from zero.

24. A device according to claim 1 or 12 including means for producing a short phased motion of the syringe regardless of how long the second means detects the presence of an animal to be injected in position on the said work plate and means for retaining the syringe in its second position.

25. A device according to claim 1 wherein the syringe is journaled for rapid translational movement in a slot in a block mounted on the opposite side of the work plate and wherein the syringe is connected to the first means by:
a) a syringe coupling attachment which has an open recess therein and which is carried by the said first means, b) a shaft carried by the syringe and having an enlargement there-on sized and positioned to fit into the recess in the syringe coupling attachment, whereby the syringe and the shaft may be simply moved in and out of place in the block and the syringe coupling attachment, respectively.

26. A device according to claim 25 wherein said block is made out of a resilient material and the width of the slot therein is less than the width of said syringe, whereby said syringe is held by the resiliency of said block.

27. A device according to claim 25 wherein the recess in said syringe coupling attachment opens upwardly.