Straw charging and feeding apparatus
United States Patent 1 Randolph et al.  
 [ Apr. 29, 1975 STRAW CHARGING AND FEEDING Primur E.\&#39;aminerHoust0n 3. Bell. Jr.  
  APPARATUS Attorney. Agent. or FirmGregg, Hendricson, Caplan [76] Inventors: Arthur J. Randolph, 47l l 1 Sonoma &amp; Becker Hwy; Albertus G. Horsting, 6685 Sonoma Hwyx, both of Santa Rosa. [57] ABSTRACT Calif. 95405 Apparatus for moving successive. small. hollow cylin- [22] Filed: Aug. 2,1973 drical straws from a hopper to a charging station [21] Appl No: 384,937 whereat the straws are charged with a liquid and thence to a pickup station for removal of the straws for use. Straw charging is accomplished by hypoder- [52] US. Cl. l4l/l75; l4l/325; 128/1 mic syringe mounted on a carriage moved back and [5 1] Int. Cl B65b 43/48 forth to insert the syringe needle into successi e [58] Field of Search l4l/l29l9l. straws at the charging station and discharge of liquid l4l/325; lZtl/l 234; 23/253 259 from the syring is accomplished by a syringe operator including a piston actuated ratchet engaging a [56] References Cited threaded shaft contacting the syringe plunger with the UNITED STATES PATENTS operator moving with the syringe carriage and with re- ?&#34;572155 [0/195] Hoyt H max/234 spect thereto as the threaded shaft is advanced during 1899789 8/1959 Smith I y V I V I |4m73 each liquid ejection. The invention is particularly ap- 3343 539 9/!967 Moorhousc 128/234 plicable to filling straws with avian species semen for 1591761 7/1971 Lorcnz l4l/I55 insemination. 1683.977 8/1972 Crowe ct al. l4l/l30 [0 Claims, 18 Drawing Figures FATENTED APR 2 91975 SHEHIBF 8 PATENTEDAPRZSIBTS FIG- 3 SHEEI 3 BF 8 PATENTEmPazsmrs 3,880.21 0  
 sum 5 or a FMENTED APR 2 91975 SHEET 7 BF 8 STRAW CHARGING AND FEEDING APPARATUS BACKGROUND OF INVENTION In the artificial insemination of fowl, such as turkeys. it has been conventional to employ small. hollow cylinders, commonly termed straws. which are manually filled with turkey semen and are then employed for applying the straw charge to a hen turkey. These straws are utilized in order to accomplish a relatively uniform semen application to each hen.  
  It is known that, in the handling of turkey semen. it is necessary to maintain controlled temperature conditions and also it is advantageous to maintain sterile conditions. Inasmuch as artificial turkey insemination is commonly carried out under a wide variety of circumstances and in various locations. including open fields. accomplishment ofthe foregoing objectives has proven difficult. Naturally manual handling ofthe semen or apparatus employed therewith is to be avoided. It is furthermore necessary or at least advantageous for the semen to be applied to the hen turkey as soon as possible after obtaining the semen from the tom turkey. Any delays in charging straws are naturally disadvantageous. Present day methods of filling straws or the like for artificial turkey insemination are cumbersome and time-consuming.  
 SUMMARY OF INVENTION The present invention provides an automated straw feed and delivery mechanism particularly adapted for use in the field of artificial turkey insemination. The plurality of small, hollow glass or plastic tubes. hereinafter termed straws. are placed in a hopper and a piston operated slide plate engages the hopper to pick up a single straw therefrom and first move the straw to a charging station. A hypodermic syringe adapted to contain a liquid such as turkey semen is mounted on a piston operated carriage for movement ofthe syringe needle into and out of a straw at the discharge station. The syringe plunger is advanced an adjustable predetermined amount each time that the syringe needle is inserted in the straw and this is herein accomplished by a threaded shaft engaging the syringe plunger and ro tated in threads by a piston operated ratchet means a predetermined degree of rotation for each actuation. Operation of the charging means is automatically terminated when the syringe is empty and provision is made for easily replacing the syringe and returning the threaded shaft to an adjusted initial position to operate upon the next filled syringe inserted in the apparatus.  
  Each charged straw is moved from a charging station to a pickup station whereat the apparatus is automatically inactivated and remains is such condition until the straw is removed as by means of attachment to a flexible tube or the like which is employed for actual insemination operations. Removal ofa charged straw reactivates the mechanism hereof to return the slide plate by piston operation to engage another straw at the hopper and to move same to the charging station. Following charging, the charged straw is then moved to the pickup station and the sequence of events repeats. The entire apparatus hereof is enclosed in a housing to protect the apparatus and the semen from contaminating influences and is provided with heat control means for maintaining a desired temperature within the housing for minimizing deleterious effects upon the semen employed therein.  
 DESCRIPTION OF FIGURES The present invention is illustrated as to preferred embodiments thereof in the accompanying drawings wherein:  
  FIG. 1 is a plan view of a preferred embodiment of the apparatus of the present invention;  
  FIG. 2 is a sectional elevational view taken in the plane 22 of FIG. 1;  
  FIG. 3 is an elevational view taken in the plane 33 of FIG. 1 and illustrating the straw feed mechanism;  
  FIGS. 4 and 5 are schematic illustrations of the straw feed mechanism in different positions of operation;  
  FIG. 6 is an end elevational view of the straw release mechanism taken in the plane 66 of FIG. 2;  
  FIG. 7 is a plan view of the mechanism of FIG. 3 taken in the plane 77 of FIG. 2;  
  FIGS. 8 and 9 are views taken in the same planes as FIGS. 6 and 7, respectively, and showing the apparatus in a different stage of operation;  
  FIG. 10 is a partial central sectional view taken longitudinally through serum injection means and taken in the plane 10-10 of FIG. 1&#39;.  
  FIG. 11 is a central longitudinal sectional view of serum feed means and taken in the plane 11-11 of FIG. 1;  
  FIG. 12 is an end elevational view of syringe drive means taken in the plane 12-12 of FIG. 1;  
  FIG. 13 is a transverse sectional view taken in the plane 13-13 of FIG. 11;  
  FIG. 14 is a view taken in the same plane as FIG. 10 and showing the syringe inserted in a straw at the charging station;  
  FIG. 15 is a vertical sectional view taken transversely through the control means in the plane 15-15 of FIG.  
  FIG. 16 is a schematic piping and wiring diagram of an alternative embodiment of the present invention;  
  FIG. 17 is a sectional elevational view of the alternative embodiment of FIG. 16; and  
  FIG. 18 is a top plan view of the embodiment of FIG. 16.  
 DESCRIPTION OF PREFERRED EMBODIMENT Referring now to FIGS. 1 and 2 of the drawings, it will be seen that there are generally provided a hopper 21 adapted to contain straws which may be formed as small, hollow glass or plastic cylinders which are moved by a slide plate 23 from the hopper first to a charging station 24 and then to pickup station 26. Movement of the slide 23 is accomplished by piston drive means 27 in a controllable fashion as described below.  
  Individual straws are charged by hypodermic charging means 31 reciprocally moved into and out of engagement with successive straws by a piston 32. A predetermined amount of liquid is ejected from the charging means in engagement with a straw by syringe operator 33.  
  The illustrated embodiment of the present invention is preferably pneumatically operated, although it will, of course, be appreciated that a hydraulic system may be employed, and there is illustrated at 34 sequencing means for the apparatus driven by an electric motor 36.  
  Considering now the movement of an individual straw from the hopper to the charging station and thence to the pickup station, reference is made to FIGS. 2, 3, 4 and 5 of the drawings. The hopper 21 is provided with an inclined lower floor 41 which is open for a short distance to the front wall of the hopper with the slide plate 23 disposed in sliding relation beneath this floor across the opening 42. A triangle block 45 is disposed across the hopper at the lower front end thereof, as shown. The slide plate 23, as shown in FIG. 2. is inclined and has a transverse slot 43 thereacross adjacent the lower end of the slide plate. A pair of bars 44 and 46 are secured to the under side of the slide plate in extension longitudinally thereof and each bar carries a pair of wheels 47 and 48 mounted for rotation beneath the bars on axles normal to the bars. The wheels 47 and 48 are formed with V-shaped peripheries and engage V-shaped rails 49 mounted on a support plate 51 secured as by brackets 52 to the side walls of the hopper 21. It will be seen that the slide plate is thus mounted for movement along the tracks 49 between an upper position wherein the slide plate groove 43 is dis posed within the hopper to receive a straw and the pickup position of the slide plate illustrated in FIG. 2. It is noted in this respect that there is provided a leaf spring 53 secured to the front wall of the hopper and bearing upon the upper surface of the slide plate. This spring will then extend over the slide plate groove 43 at the charging station 24 for reasons discussed below. Controlled movement of the slide plate along the tracks is herein accomplished by the drive means 27 via drive bar 56 secured across the outer ends of the bars 44 and 46 and attached by a clevis connection 57 to a piston rod 58 extending alongside and longitudinally of the slide plate 23. The piston rod 58 extends from a pneumatic cylinder 61. It is herein provided that the slide plate shall be moved first to the charging station and then to the pickup station and thus this two displacement movement is provided for herein by a second pneumatic cylinder 62. In the illustrated embodiment of the present invention the cylinders 61 and 62 are disposed in side by side relationship with the upper ends of the two cylinders fixed together by linkage 63. The cylinder 62 is shown to be disposed beneath the cylinder 61 and rests upon an angle iron or the like 64 secured to the side of the hopper 21. The piston rod 66 of cylinder 62 is coupled by adjusting means 67 to an adjusting bolt 68 secured to a fixed bracket 69 mounted on the side wall of the hopper. It will be seen that actuation of the cylinder 62 will thus move the cylinder itself upwardly along the angle iron 64 to conse quently move the other cylinder 61 in the same direction. Conversely. actuation of cylinder 62 to lower it along the angle iron 64 will also lower the cylinder 61. A retainer 71 is secured to the side of the angle 64 and bears on the upper surfaces of the cylinders 61 and 62 in order to prevent any movement of the cylinders 61 and 62 except longitudinally of the angle iron 64.  
  Considering now operation of the drive means 27, reference is made to FIGS. 4 and 5. In FIG. 4 the cylinder 62 is illustrated to be actuated to extend the piston rod 67 therefrom for holding the cylinders 61 and 62 in their uppermost position with the piston rod 58 of the cylinder 61 retracted. This then disposes the slide plate groove 43 in position to receive a straw from the hopper. the groove being disposed immediately beyond the triangle plate 45, as shown. Operation of the cylinder 62 to draw the piston rod 67 therein lowers the assembly to dispose the slide plate groove 43 at the charging station 24. As illustrated in FIG. 5, further movement of the straw to the pickup station 26 is accomplished by actuating the cylinder 61 to extend the piston rod 58 therefrom. Return of the slide plate 23 to place the groove 43 thereof in the hopper 21 is accomplished by actuating cylinder 62 to extend the piston rod 66 therefrom and actuating cylinder 61 to withdraw the piston rod 58 therein.  
  At the pickup station 26 provision is made for removing a straw 22 from the slide plate 23 and in this respect reference is made to FIGS. 6, 7, 8 and 9. The outer end of the slide plate 23 is provided with a lateral indentation 71 on the outer side thereof at the groove 43, as best shown in FIGS. 7 and 9. The slide plate is also provided with a longitudinal slot 72 extending from the outer end thereof past the groove 43 so that the straw 22 bridges the slot 72. There is provided a valve 76 in position for operation by the slide bar as the groove 43 reaches the pickup station 26. This valve 76 may be mounted on the lower end of the support plate 51 with the valve actuator engaged, for example, by the drive bar 56. A piston block 77 is mounted on a bracket 78 secured to the under side of the support plate 51 at the outer end thereof and is bored to contain a piston 81 having a compression spring 82 urging the piston out of the block. The piston 81 has a piston rod 83 extending through a seal in the block exteriorly thereof and the valve 76 is connected to the bore in the block so that actuation of the valve 76 by the slide bar apparatus applies air pressure, for example. above the piston to compress the spring 82. The block 77 is also bored to slidably accommodate a switch rod 86 extending parallel to the piston rod 83 and a crosspiece 87 is connected between the piston rod and switch rod. A leaf spring 88 is connected to and extends at an angle from the crosspiece 87 above the slide bar 23 in extension into the end longitudinal slot 72 in this slide plate.  
  Also carried on the bracket 78 beneath the block 77 is an electrical switch 91 having an actuator 92 extending upwardly therefrom beneath the switch rod 86. It will thus be seen that, in the position illustrated in FIGS. 6 and 7, the slide plate mechanism has just arrived at the position where it will then actuate the valve 76 so that the leaf spring 88 is disposed above the slide plate and the switch 91 is not actuated. In FIGS. 8 and 9 the apparatus is illustrated after the valve 76 is actuated to force the piston 81 downwardly for compression of the spring 82 and thus to draw the leaf spring 88 down into engagement with the straw 22. This will be seen to dispose a concave end 96 of the leaf spring about the upper surface of the straw 22 so as to hold the straw against movement to the left in FIG. 8, for example. Removal of the straw 22 from the slide plate 23 may be accomplished by slipping the end of a small rubber tube 97 over the end of the straw 22 exposed at the notch 71 in the side of the slide plate 23. The tube grips the end of the straw, as illustrated in FIG. 8, and thus withdrawal of the tube will withdraw the straw inasmuch as the leaf spring 88 merely presses lightly on the upper surface of the straw. The piston 81 and switch rod 86 are maintained in the position illustrated in FIG. 8 by pressure of the leaf spring 88 on the straw. however, as the straw is removed. the leaf spring is then free to move downwardly into the slide plate slot 72 and thus the piston and switch rod 86 move downwardly somewhat further so that the switch rod engages the switch actuator 92 to operate the switch.  
  Considering now the charging of individual straws by the apparatus of the present invention. reference is first made to FIG. 1 wherein there is illustrated a hypodermic syringe 101 mounted on a carriage 102 controllably moved by the piston 32. As illustrated in FIGS. 10, l l and 12, the carriage moves on tracks 103 by wheels 104 mounted on vertical axles beneath the carriage and having notched periphery engaging the V-shaped tracks. The tracks 103 are suitably mounted on a base 106 which also carries the hopper 21 and previously described elements of the present invention. The cylinder 32 has one end thereof secured to a bracket I07 mounted on the base 106. The piston rod of the cylinder 32 is connected to a lag extending laterally from the carriage 102 so that operation of the piston 32 controllably moves the carriage along the tracks 103.  
  On the upper surface of the carriage 102 there is mounted a longitudinally extending block 111 having a groove therein in which there is disposed the hypodermic syringe 101. As shown in FIG. 10. a transverse slot 112 in the block 111 accommodates the flanged end of the syringe cylinder. A cap 113 is removably mounted on the block to engage the syringe and hold it in position. again as illustrated in FIG. 10. The syringe 101 includes a hypodermic needle 114 in extension from the outer end thereof for axial alignment with the slide plate groove 43 at the charging station 24. The carriage is moved by the cylinder 32 toward the slide plate to insert the needle 114 in a straw for charging the straw, as illustrated in FIG. 14. After charging of the straw, the carriage is retracted by the cylinder 32 to remove the needle from the straw so that the straw may then be moved on to the pickup station 26. A stop plate 116 mounted on the hopper 21 extends alongside the opposite side of the slide plate 23 from the needle 114 at the charging station to prevent movement of the straw when the needle is inserted therein. An adjustable stop means 117 is mounted on the carriage 102 to engage a side of the hopper 21 at the position that the needle is inserted in a straw in order to prevent any possible overtravel.  
  The hypodermic syringe 101 includes a plunger 12] fitting in a barrel 122 of the syringe. This plunger is controllably moved for each ejection of liquid from the syringe by threaded shaft 123 maintained in axial alignment with the syringe by slidable extension through a bore in a raised portion 124 of the block 111. This threaded shaft engages the outer end of the plunger 121 and is controllably moved axially of the syringe a predetermined distance each time that the needle 114 enters a straw for charging the straw with a liquid 126 carried in the syringe barrel. Movement ofthe threaded shaft 123 is accomplished by a ratchet mechanism best illustrated in FIGS. 1 and 12. The shaft 123 has a knob 127 on the outer end thereof for initially setting the shaft position. as further noted below.  
  The syringe operator 33 includes a side plate 131 car rying a cylinder 132. The cylinder 132 is pivotally connected to a pair of upright supports 133 on the outer end of the plate 131. The outer end of the threaded shaft 123 is not threaded and a pair of bearings 136 and 137 are disposed about this unthreaded portion of the shaft and the bearing mounts are secured to the plate 131. The plate 131 rests upon the smooth side rod 138 mounted on the upper surface of the carriage 102 in parallel spaced relationship to the threaded shaft 123.  
  The threaded shaft is rotated by the cylinder 132 for advancing the shaft a predetermined amount for each actuation of the mechanism. A piston rod 139 is linked by a clevis 141 to an arm 142 rotatably mounted on the threaded portion of the shaft 123 between the bearings 136 and 137. Adjacent the arm 142 there is affixed to the shaft a ratchet wheel 143 and pawl 144 is pivotally 5 mounted on the arm 142 above the ratchet wheel 143, as illustrated in FIG. 12. Actuation of the cylinder 132 to extend the piston rod 139 therefrom will pivot the arm 142 in a clockwise direction of FIG. 12 so that the pawl 144 will engage the teeth on the ratchet wheel 143 to rotate the threaded shaft 123. It is important to provide a controlled and invariable shaft rotation for each operation of the cylinder 132 and to this end there is provided an adjusting bolt 146 threaded through an upright bracket 147 and directed toward the backside of the arm 142 for engaging a flat surface thereon to limit counterclockwise movement of the arm. A lock nut 148 secures the adjusting bolt 146 in adjusted position. The cylinder 132 is operated as by air pressure to move the piston rod 139 the maximum amount out of the cylinder and then return the piston rod until the arm 142 engages the adjusting bolt 146. This then provides a predetermined and adjustable piston stroke so that the threaded shaft is rotated through a predetermined angle for each operation of the cylinder 132.  
  The syringe operator 33 is provided for the purpose of advancing the threaded shaft 123 a predetermined amount for each actuation in order to move the syringe plunger a predetermined amount for forcing a known amount of liquid from the syringe into the straw. There has been described above mechanism for precisely rotating the threaded shaft 123 and provision is herein made for changing this rotation into shaft translation. In this respect reference is made to FIGS. 11 and 13 wherein there is shown an arm pivotally mounted in a slot 152 transversely across the top of the raised block portion 124 of the carriage. The arm 151 has a half cylindrical identation 153 thereacross which is threaded to engage the upper portion of the threaded shaft at the slot 152. Firm engagements of the arm threads and threads on the shaft 123 are ensured by a tension spring 154 connected between the carriage 102 and the arm 151 on the opposite end thereof from the pivotal connection of same with the block portion 124. The arm 151 is furthermore provided with an extension 156 so that an operator may press on this extension to pivot the arm upwardly out of threaded engagement with the shaft 123 for reasons described below.  
  Further with regard to the syringe operator there is provided an adjustable switch actuator 157 on the side of the side plate 131 toward the syringe 101 for engag ing the arm of an electrical switch 158 mounted on the carriage 102. This switch is provided for the purpose of terminating operation of the apparatus when the liquid in the syringe has been exhausted.  
  Considering now briefly the operation of the syringe operator and referring to FIGS. 1 and 10 to 14, it will be seen that operation of the cylinder 132 to extend the piston arm 139 therefrom will rotate the shaft 123 a predetermined amount. This shaft in rotation causes the shaft to move to the right in FIG. 1 by virtue of the threaded engagement of the shaft with the arm 151. With the syringe loaded and the plunger 121 thus extended from the syringe barrel. the shaft 123 engaging the piston will thus move the piston to the right in FIGS. 10 and 14, for example, to thus force a predetermined amount of liquid from the needle 114 of the syringe. With this needle inserted in a straw. as illustrated in FIG. 14. this liquid is then forced into the straw to charge the straw. In is noted that the needle is inserted in the straw by operation of the carriage drive piston 32 to move the carriage 102 to the right in FIG. 1. Following charging of the straw the carriage is returned to the left to withdraw the needle from the straw. It will be seen that the syringe operator must move relative to the carriage inasmuch as it moves with the threaded shaft 123. To this end the operator rides on the slide rod 138. Thus, the syringe operator is movable with the carriage 102 but also moves with respect to the carriage 102.  
  The present invention incorporates a plurality of pneumatic or hydraulic cylinders, as described above, and these are sequentially operated to carry out the functions of the present invention by the sequencing means 34., generally illustrated in FIGS. 1 and 15. The small electric motor 36 is connected as by a drive chain 161 to a cam shaft 162 of the sequencer 34. This sequencer includes a plurality of control valves 163 having actuators in the form of cam followers 164 riding on the cams and the cam shaft 162. The valves 163 are connected to the cylinders 61, 62, 32 and 132, described above. The valves 163 are connected to a source of pressurized air for pneumatic operation and are sequentially operated to apply air pressure to the above-noted cylinders and to exhaust the cylinders in accordance with the desired sequence of operations as set by the configurations of the cams of the sequencer. The sequence of operations is .described below.  
  The apparatus of the present invention is enclosed in a housing or cover 166 which is preferably formed of a heat insulating material. Additionally there is provided a cover 167 extending about the pickup station 126 which will be seen to be disposed below and in front of the housing 166. An opening 168 in the side of the cover 167 affords access of the discharge station whereby an operator may remove a charged straw from the slide plate. Further with regard to this removal and utilization of the charged straw, it is noted that the flexible tube 97 of FIG. 9 may be connected through a valve 171 to a source of low pressure air 172. An operator having the tube 97 in his hand then slips the tube over the end of the straw at the notch 71 of the slide plate so that the tube grips the straw, as illustrated in FIG. 8. He then withdraws the straw or tube which readily slides from the groove 43 in the slide plate and, with a hen turkey in position, then places the straw in the proper location for semen discharge therefrom and actuates the valve 171 so that the low air pressure in the tube pushes the semen from the straw. The straw is then discarded and the operator reaches the tube into the pickup station 26 and attaches it to the charged straw which has been moved into that station while the actual insemination operation was being carried out. It will be appreciated that movement of the straw from the charging station to the pickup station is advantageous in placing the charged straw in an available position for retrieval or pickup. Commonly, the apparatus of the present invention may be mounted above an insemination station with the pickup station hereof extending downwardly so that an operator may readily reach upwardly and engage the flexible tube with a charged straw and then bring a tube back down with a charged straw thereon for turkey insemination. It is also noted that separation of the pickup station from the charging station facilitates construction of the apparatus in that complications of the charging station are thereby minimized.  
  A sequence of operations of the present invention is initiated by removal of a charged straw from the pickup station 26. As the straw is removed, the leaf spring 88 moves downwardly into the slide plate slot 72 so that the switch actuator rod 86 moves downwardly in the cylinder block 77 to operate the switch 91. This switch initiates operation of the drive motor 36 to rotate the cam shaft 162 of the sequencer 34. The sequencer 34 then applies air pressure to the lower end of the cylinder 61 to withdraw the piston rod 58 therein and to the upper end of cylinder 62 to force the cylinders 61 and 62 upwardly in the angle 64. This withdraws the slide plate to its uppermost position whereat the groove 43 therein is disposed well within the hopper 21 so that a straw drops into this groove. The sequencer then reverses the application of air to the cylinder 62 to apply air pressure to the lower end thereof whereby the cylinders 61 and 62 move downwardly in the angle 64 to move the slide plate downwardly and align the groove 43 and straw therein with the needle 114 of the syringe at the charging station 24. The straw is held in the groove at this station by leaf spring 53 and when the slide plate stops in this position. the sequencer then applies air pressure to the cylinder 62 for driving the carriage 102 to the right of FIG. 1 and inserting the needle of the syringe in the straw in the position of FIG. 14. The extent of travel of carriage 102 is limited by the adjustable stop 117 on the carriage engaging the side of the hopper 21. The sequencer 34 then applies air pressure to the left side of cylinder 132, as viewed in FIG. 12, to force the piston rod 139 outwardly therefrom and to consequently rotate the arm 142 and by means of the pawl 144 rotate the ratchet wheel 143 attached to the shaft 123 is rotated by engagement with the halfthreaded arm 151 in the raised portion 124 of the block 111. This moves the threaded shaft to the right as in FIG. 10, for example, and, inasmuch as the shaft bears on the plunger 121 of the syringe, the plunger will be moved into the syringe barrel a predetermined distance to thus force a predetermined amount of liquid such as turkey semen from the needle 114 into the straw 22. The sequencer then reverses the application of air pressure to the piston 32 while applying air to the right hand side thereof, as viewed in FIG. 1, so that the piston rod of the cylinder is retracted and the carriage 102 is moved to the left in FIG. 1 for retracting the needle from the straw. At the same time the air pressure is removed from piston 132 so that the spring 149 swings the arm 142 to the left of FIG. 12. The pawl 144 rides upon the teeth of the ratchet wheel during this direction of movement of the arm 142 and, at the end of the arm travel as determined by the adjusting bolt 146, the pawl drops to engagement with a ratchet tooth and is ready for return movement. It will be appreciated that during this operation the syringe operator has moved on the carriage inasmuch as the operator is carried by the threaded shaft 123 and this movement is accomplished by sliding along the slide rod 138 of the upper surface of the carriage. The sequencer then reverses the application of air pressure to the cylinder 61 to apply air to the upper end thereof for forcing the piston rod 58 outwardly of the cylinder and this then moves the slide plate 23 downwardly along the tract 49 until the slide plate or members carried thereby engages the actuator of the valve 76 at the end of slide plate travel.  
  At this time in the sequence of operations the piston 81 at the receiving station is in the position illustrated in FIG. 6 and air is applied above the piston by operation of the valve 76 to force the piston downwardly into the position illustrated in FlG. 8 where-at the leaf spring 88 engages the straw at the pickup station. A sequence of operations has thus been completed for it is noted that the above-described sequence commenced with a charged straw at the pickup station. Removal of the straw from the pickup station allows the piston 81 to move further downwardly in the piston block 77 at the receiving station as the leaf spring 88 moves into the end slot 72 of the slide plate and this causes the switch rod 86 to engage the switch arm 92 and operate the switch 9] to initiate the next cycle of operation. The sequencer itself terminates operation at the end of one cycle as by a cam 176 engaging a motor stop switch 178.  
  lt is of interest to note that the mechanism of the present invention involving the hypodermic syringe 101 is particularly arranged for ready replacement of an individual syringe as it is emptied and adjustment of the mechanism to ensure full charging of the next straw from the full syringe. In this respect it will be seen that the arm 151 may be readily pivoted upwardly so that the syringe operator 33 and threaded shaft 123 may be readily slid to the left in FIG. 1 to make room for insertion of a filled syringe with the plunger extending therefrom. The cap 113 is lifted and the old syringe taken out, the other one placed in position and locked via reattachment of the cap 113. With the arm 151 pivoted upwardly, the threaded shaft is then moved into engagement with the syringe plunger and the arm released to pivot into further engagement with the shaft. The knob 127 on the left end of threaded shaft 123 is then turned to move the shaft until a bit of liquid is expelled from the needle 114.  
  it is also noted that, as the syringe is slowly emptied by successive ejections of liquid therefrom into straws by the present invention, the syringe operator 33 moves to the right in FIG. 1 as the threaded shaft 123 is advanced. When the syringe plunger is substantially entirely depressed into the syringe barrel, the switch operator 157 carried by the syringe operator engages the switch 158 to thus deactivate the entire mechanism. This may be accompanied by the lighting of a light or the like so that an operator will be apprised of the fact that the syringe is empty and replacement is necessary in accordance with the steps noted above.  
  The present invention may be modified in a variety of ways and yet retain the capability of carrying out all or at least the majority of the functions of the present invention. In this respect reference is made to the FIGS. 16, 17 and 18 illustrating an embodiment of the present invention wherein the pickup and charging stations are combined. and wherein alternative drive and control means are employed.  
  Referring first to FlG. l6, and noting that elements of the embodiment thereof which are identical to those previously described carry the same numerals as previously employed, there will be seen to be provided the slide plate 23 adapted to be moved by a single pneumatic cylinder 201. This cylinder 201 is connected by air lines to a solenoid operated reversible valve 202 having an air inlet line 203 connected to a source of air (not shown) and an exhaust line 204 connected to the atmosphere. At the charging station 24 there is provided an electrical switch 206 having a mechanically movable actuator 207 normally riding on the upper surface of the slide 23 to hold the switch 206 open, and movable into the plate notch 43 when same is at the charging station to close the switch 206. The stationary contact switch of 206 is connected through the up&#39; solenoid 207 of solenoid valve 202 to ground and the movable contact of the switch 206 is connected through the switch 158 to one movable contact of a ganged switch 208.  
  The gang switch 208 is a manually operable switch having three movable contacts 2080, 208b and 208C. The contact 208a is connected through the down&#34; solenoid 209 of valve 202 to ground. The contact 208b is connected to a power supply terminal 211 and the third movable contact 2086 is connected as noted above, through switch 158 to switch 206.  
  The embodiment of the present invention illustrated in FIG. 16 provides for electrical control of slide movement by means of an upper limit switch 216 and a lower limit switch 217. The lower movable contact 2080 of ganged switch 208 has the stationary contact thereof connected to the stationary contact of lower limit switch 217, and the movable contact of this latter switch 217 is connected with the stationary contact adapted to be engaged by the ganged switch contact 20819. The upper limit switch 216 has the stationary contact thereof connected to the stationary contact adapted to be engaged by the ganged switch movable contact 208a and has the movable contact connected to the movable contact ofswitch 217 and to the stationary contact adapted to be engaged by the movable contact 208!) of gang switch 208.  
  Actuation of the switches 216 and 217 is accomplished by switch actuators 222 and 223, respectively, carried by the slide 23. The switches are appropriately located so that movement of the slide 23 upwardly, as described below, will cause the actuator 222 to engage the movable contact of switch 216 and thus close the switch. With the manually operable gang switch 208 closed so that the system is operable, closure of switch 216 applies power through gang switch contacts 208a and 20812 to the down solenoid 209 of valve 202. This then causes air or liquid pressure to be applied to the upper portion of drive cylinder 20] so that the slide 23 is moved downwardly in the tracks thereof. As the slide moves to position wherein a straw 22 carried thereby is disposed at the charging station in line with the hypodermic needle 114, the switch actuator 223 engages the movable contact of switch 217 and closes this switch. This then in part completes the circuit from the power supply terminal 211 through the up&#34; solenoid 207 of valve 202, however the switch 206 is maintained open so that this circuit is not completed. The straw 22 in the plate 23 holds the valve actuator 207 in position to maintain switch 206 open. However, upon removal of a straw carried by the plate, switch 206 closes and thus completes the above noted circuit through the up&#34; solenoid 207 of valve 206 so that the valve reverses the application of air pressure to cylinder 201 and causes the cylinder to withdraw the piston rod and thus move the slide plate 23 upwardly in FIG. 16. It will be appreciated that valve 201 remains in the condition that it is set by energization of either the up&#34; or *down&#34; solenoids until such condition is reversed by subsequent energization of the opposite solenoid.  
  In addition to the movement of the slide plate 23 cer tain additional controls are herein provided. Such controls need not be electrically energized and may include a pneumatic valve 231 disposed in position adjacent the slide plate mechanism for engagement of the control means 232 thereof with a valve actuator 233 carried by the slide plate and engaging the valve control when the slide plate has moved a straw 22 into alignment with the syringe 114 at the charging station. Operation of valve 231 causes air to be applied therethrough from an air supply (not shown) to the rear end of the hypodermic drive piston 32 which moves the syringe 114 into the straw 22. As the syringe reaches the desired depth of penetration of the straw, a pneumatic valve 236 is operated by valve control means 237 extending therefrom engaging a valve actuator 238 on the side of the hopper 21. Actuation or opening of valve 236 causes air to be applied to hypodermic syringe operator cylinder 132 which ejects a predetermined amount of fluid from the needle 114 into the straw 22. It will be appreciated that the travel of the syringe to the right in FIG. 16 to dispose the needle 114 thereof a desired amount into the straw 22, may be mechanically terminated.  
  Physical removal of the charged straw 22 from the slide plate of the charging station 24 allows switch 206 to close and thus complete a circuit through switch 158, contact 208( of switch 208, switch 216 and switch contact 208b of switch 208 to the power supply terminal 218 so that the up solen&#39;oid 207 of valve 202 is operated. This causes the slide plate to move upwardly and and retract the slide plate groove 43 from the charging station. Slide plate movement upwardly releases control valve 231 so that pressure is applied to the opposite end of cylinder 32 for retracting the hypodermic needle. The slide plate moves upwardly until the switch actuator 222 thereon engages the movable contact of switch 216 for completing a circuit through the &#34;down&#34; solenoid 209 of valve 202 that in turn reverses the application of pressure to the cylinder 201 so that the slide plate is then moved downwardly again.  
  It will be seen that there has been described above a complete sequence of operations employing in general a nomenclature and primarily the elements described above in connection with the first embodiment of the present invention. It is to be appreciated that valve 236 operates to exhaust the cylinder 132 when the valve actuator 237 is again extended by removal from engagement with actuator 238. Additionally it is noted that switch 158 is the same as, and is operated in the same manner as, the similarly numbered switch in FIG. 1.  
  The physical construction and mounting of the slide plate 23 in the embodiment of FIGS. 16 to 18 may be similar if not identical to that of the embodiment described above in connection with FIGS. 1 to 15. Thus the slide 23 moves along tracks 49 upon wheels 47 to move the slide plate groove 43 from the interior of the hopper and an opening 42 in the lower floor 41 thereof to the charging station 24. In this embodiment of the present invention. the charging station is also the pick up station and consequently the drive means for the slide plate may be materially simplified. As noted above, only a single pneumatic cylinder 201 is provided for moving the slide plate. For many applications is adequate that the charged straw be provided only at the exterior of the hopper without requiring that the straw be moved a substantial distance either below or away from the hopper. It will be seen in FIG. 17 particularly, that the slide plate is moved along a plane which is at less of an angle to horizontal than the plane in which the slide plate is moved in the embodiment of FIG. 2. Here again it will be apparent to those skilled in the art that the angle at which the slide plate is moved is readily variable to accommodate the needs of particular applications of the present invention.  
  The switch 206 may be physically mounted upon the plate 241 secured to the front of the hopper, above the slide plate 23 as illustrated in FIG. 17. Additionally, the switch 216 may be physically mounted upon the upper end of the support plate 51 with a movable contact thereof or actuator for such contact extending in line with the switch actuator 222 carried on the upper end of the slide plate 23. The switch actuator 223 and value actuator 233 may be carried upon elongated angle arms secured to the upper end of the slide plate 23 in order to position these actuators for engaging the switch 217 and valve 231, respectively, as the slide plate arrives at a position wherein a straw carried thereby is in the charging station.  
  The same general considerations of the present invention described in some detail above in connection with FIGS. 1 to 15 in most part apply directly to the simplified embodiment of FIGS. 16 to 18. In addition to the variations between the illustrated and described embodiments of FIGS. 1 to 15 and FIGS. 16 to 18, it will be appreciated that numerous other modifications and variations are possible within the scope of the present invention.  
  Although the present invention is generally applicable to the charging of small hollow tubes or straws with a predetermined amount of liquid, the invention is particularly applicable and useful in the field of poultry insemination. In the handling of poultry semen, and in particular turkey semen, it is necessary to carefully control the ambient conditions in order to prevent damage to same. It is also noted that the present invention when employed for poultry insemination may well be physically located in a wide variety of places such as out in the middle of a field or the like, where temperatures may vary from very cold to very hot. Thus there is preferably provided, particularly for such applications, means for maintaining the present apparatus, and particularly the syringe thereof, at a controlled temperature. Such means may include one or more thermostats or temperature sensing means 301 within the housing 166 and operating or controlling heating and cooling means 302, also disposed within the housing. It is also preferable that the housing 166 be sealed to prevent the intrusion of dust or the like during straw charging. Under those conditions wherein the apparatus of the present invention is employed in remote locations there would be provided suitable power supply means such as a portable generator or the like to provide energy for the system, both to operate the electrical and fluid portions of the system and also to energize heating and cooling means as may be required.  
  It will be seen that the present invention provides a truly automated mechanism for charging successive minute, hollow cylinders with a predetermined amount of liquid and moving such cylinders into position for removal from the mechanism hereof an subsequent utilization. It will be appreciated that numerous modifications and variations in the illustrated embodiment of the present invention are possible and thus it is not intended to limit the present invention to the precise terms of description or details of illustration.  
 What is claimed is:  
  1. Apparatus for charging small hollow tubes or straws with a predetermined amount of liquid comprising:  
 a hopper adapted to contain a plurality of tubes to be charged and having a slotted floor,  
 a slide plate mounted for controlled movement immediately beneath the hopper floor and having a transverse groove therein for receiving a tube from the hopper and moving the tube therefrom to a charging station,  
 a carriage mounted for reciprocal movement toward and away from said charging station parallel to the slide plate groove.  
 a syringe mounted on said carriage and having a plunger and a needle aligned with the axes of said slide plate groove at said charging station,  
 means controllably advancing said plunger in said syringe a predetermined amount of each actuation. and  
 control means operable upon positioning of a straw in said charging station by said slide plate for moving the carriage toward the charging station to insert the syringe needle into the straw and advancing said syringe plunger to inject a predetermined amount of liquid from the syringe into the straw.  
  2. The apparatus of claim I further defined by the means advancing said plunger comprising:  
 a threaded shaft extending through a threaded member on said carriage into axial engagement with said plunger and carrying a ratchet gear,  
 a pivot link carrying a pawl engaging said ratchet,  
 and  
 a fluid cylinder pivotally connected between said pivot link and means movably engaging said carriage, whereby cylinder actuation of said control means rotates said shaft a predetermined amount to advance the syringe plunger said predetermined amount and also moves said cylinder along said carriage by the same amount.  
 3. The apparatus of claim 2 further defined a first limit switch mounted on said carriage in alignment with a switch actuator carried by said shaft,  
 said switch being connected to dcenergize the apparatus upon actuation by successive shaft rotations moving the syringe to complete insertion in the syringe.  
  4. The apparatus of claim 2 further defined by said threaded member comprising a block mounted on said carriage with a bore therethrough accomodating said shaft in slidable engagement therethrough and a pivotally mounted arm disposed in a transverse slot in said block across the bore with the arm having threads thereon engaging said shaft whereby the aim may be pivoted out of engagement with the shaft so that the shaft may be slid longitudinally of the block.  
  5. The apparatus of claim 1 further defined by said carriage being mounted on tracks aligned with said charging station whereby carriage movement is limited to reciprocation axially of said charging station.  
  6. The apparatus of claim 1 further defined by track means upon which said slide plate is movably mounted for slidable engagement with the underside of said hopper. and  
 fluid cylinder means engaging said slide plate and track means for controlled movement of said slide plate between positions disposing said slide plate groove under the opening in the hopper floor and said charging station.  
 7. The apparatus of claim 1 further defined by track means mounting said slide plate in slidable engagement with the underside of said hopper and extending beneath said charging station and beyond to a pickup station first and second fluid cylinders connected together and to said slide plate for controlled movement of said slide plate along said track from a retracted position with the slide plate groove beneath the hopper to said charging station and thence to said pickup station and return to said retracted position, and  
 switch means disposed to engage a straw in the slide plate groove at said pickup station for operation by straw removal to initiate the sequence of slide plate movement.  
 8. The apparatus of claim 1 further defined by said hopper having a width substantially equal to the length of said tubes and adapted to have tubes stacked therein crosswise of the hopper and all in parallel orientation, said hopper also having a bottom inclined with respect to horizontal on the opening in the hopper floor being disposed adjacent the lower end of the floor whereby tubes in the hopper migrate to the floor opening in position to successively enter the slide plate slot for removal from the hopper.  
  9. Apparatus for automatically charging small hollow tubes or straws with a predetermined amount of liquid comprising:  
 a hopper adapted to contain straws and having an opening in a floor thereof for tube removal.  
 a slide plate mounted for movement along the underside of the hopper floor and having a groove therein for receiving a straw at the floor opening and moving the straw to a charging station by slide movement,  
 a drive cylinder connected to said slide plate and moving the plate back and forth between a retracted position of straw receipt and extended position at said charging station,  
 fluid control means connected to said drive cylinder and having electrically responsive means for reversing application of fluid pressure to said cylinder,  
 limit switches disposed for engagement by the slide plate at opposite ends of plate movement and connected to said fluid control means,  
 a syringe having an actuator and a needle mounted in alignment with said charging station for movement of the needle into a straw disposed at the charging station and retraction of the needle therefrom, and  
 control means responsive to slide plate position connected to control movement of said syringe for positioning the syringe and connected to control the syringe actuator for ejecting a predetermined amount of liquid from the needle when the needle is inserted in a straw at said charging station.  
  10. The apparatus of claim 9 further defined by a switch having an operator engaging said slide plate at said charging station to engage a straw moved to the charging station and operated by straw removal from the slide plate to complete connection of one of said limit switches to said fluid control means for moving the slide plate to retracted position.