my invention generally provides elongate body 9 having band fastening structure 10 in the forward portion of the body with yoke structure 11 extending forwardly therefrom and stretching mechanism 12 carried in the rearward portion of the body to extend forwardly to the yoke structure . body 9 provides elongate body beam 13 defining laterally extending fastening ears 14 in its rearward end portion for interconnection of a handle structure by fasteners 15 extending fastenably therebetween . the forward end portion of body beam 13 carries annular support 16 defining medial channel 17 extending therethrough to allow passage of a tensioning rod and interconnected elastic band while providing guidance limits for their positional maintenance and a chamber for containment and deformation of a fastening clip . the rearward portion of body beam 13 interconnects handle body 18 carrying structurally joined depending handle 19 . handle body 18 defines forwardly extending connector plate 20 , of similar peripheral configuration to fastening ears 14 of the body beam 13 , to receive fasteners 15 extending in threaded engagement into the connector plate 20 to structurally interconnect the handle body and body beam . the handle body 18 defines medial cavity 21 to receive and carry portions of band stretching mechanism 12 . the forward wall of handle body 18 defines tensioning rod hole 23 to allow slidable passage of a tensioning rod through the handle body . handle 19 preferably supports forwardly extending grip portion 22 to make the handle more easily and comfortably grippable by a user . band fastening structure 10 of this tool is substantially the same as the structure disclosed in my prior u . s . pat . no . 5 , 188 , 637 and the fastening clip 65 used in the structure is also substantially the same as the fastening clip there disclosed . the channel for holding the fastening clip 65 is defined by the appropriate configuration of the inner wall of annular support 16 that defines the medial channel 17 therein . the annular support 16 defines axially aligned slot 66 to allow passage of the forward part of crimping lever 67 therethrough to fastenably deform a fastening clip . the medial forward part of the crimping lever 67 is pivotally carried on pivot pin 68 supported in the lower forward portion of body beam 13 for pivotal motion to allow the forward part of the crimping lever to move through slot 66 and into medial channel 17 to crimp a fastening clip in the channel upon a fastening band passing through the fastening clip . yoke structure 11 provides a generally flat , u - shaped band holding yoke formed by back 24 interconnecting forwardly and laterally outwardly extending legs 25 . back 24 of the yoke is structurally carried by the forward end portion of body beam 13 immediately rearwardly of annular support 16 . the forward outer end portions of each leg 25 carry band fastening dogs 26 pivotally mounted on the undersurface of the legs 25 by fasteners 27 extending through both elements . each band fastening dog 26 defines fastening groove 28 on its forward laterally outer edge to aid positional maintenance of an elastomeric band extending between the fastening dogs and defines a rearwardly protruding fastening lug 29 on its laterally inner edge to aid positional maintenance of the fastening dog against rotation . band release yoke 30 , 31 defined by back 30 and forwardly and laterally outwardly extending legs 31 is of a configuration similar to band holding yoke 24 , 25 except that the forwardly extending legs are somewhat shorter to avoid interference with fasteners 27 of the band holding yoke . the band release yoke 30 , 31 is carried for limited slidable motion in an elongate direction on the upper surface of the band holding yoke 24 , 25 by plural threaded fasteners 32 extending through plural elongate slots 33 defined through the band release yoke and into threaded engagement in cooperating holes defined in appropriate positions in legs 25 of the band holding yoke , so that the band release yoke may move forwardly and rearwardly for a limited distance relative to the band holding yoke . fastening pins 34 are carried by the forward portion of each leg 31 of the band release yoke 30 . 31 to depend through elongate slots 69 defined in appropriate position in each leg 25 of the band holding yoke , and project spacedly beneath the band holding yoke to contact fastening lugs 29 of the band fastening dogs 26 for selective positional maintenance of the fastening dogs against rotation . back 30 of the band release yoke 30 , 31 carries similar opposed upstanding release lever brackets 35 that support laterally extending release lever pin 36 therebetween . angulated release lever 37 is pivotally carried on the release lever pin 36 rearwardly of annular support 16 , with depending arm 37a adjacent to the annular support and manipulation arm 37b extending rearwardly and upwardly therefrom . with this structure as the angulated manipulation arm 37b is pivoted downwardly , the depending arm 37a will not move by reason of support against the rearward surface of annular support 16 and the band release yoke 30 , 31 will responsively move rearwardly to remove support of fastening pins 34 from fastening lugs 29 to allow pivotal motion of the band fastening dogs 26 to release a tensioned elastic band supported between the fastening dogs . band stretching mechanism 12 provides elongate stretching rod 38 slidably supported in holding block 41 that is carried in medial cavity 21 defined in handle body 18 . the stretching rod 38 has a length to extend from a point spacedly rearwardly of holding block 41 forwardly to the band fastening dogs 26 . the stretching rod defines band holding notch 39 in its forward end portion and structurally carries &# 34 ; d &# 34 ; ring 40 in its rearward end portion to aid manipulation . the stretching rod is carried for slidable motion in channel 64 defined in holding block 41 and in channel 17 of annular support 16 for some positional restraint of its forward portion . the stretching lever mechanism provides similar opposed mounting levers 42 pivotally carried on each side of holding block 41 by inner mounting bolt 43 extending therebetween and through the holding block . the mounting levers 42 carry medial mounting bolt 44 extending therebetween spacedly above the upper portion of holding block 41 to pivotally mount similar spaced rearwardly extending stretching rod levers 45 and the inner portion of stretching lever 46 therebetween . the outer end portions of mounting levers 42 carry outer mounting bolt 47 which extends pivotally through the medial portion of stretching lever 46 . the rearward end portions of stretching rod levers 45 pivotally carry laterally extending stretching rod lever bolt 48 extending therebetween and pivotally through stretching lever block 49 . the stretching lever block 49 defines lower elongate channel 50 to slidably receive the stretching rod 38 which extends in an elongate direction through the stretching lever block 49 and an upper channel carrying canting lever fastener 51 to movably mount stretching lever block canting lever 52 forwardly of the block . canting lever 52 depends from fastener 51 to define stretching rod hole 53 to allow movable passage of the stretching rod 38 therethrough . compression spring 54 is carried about the stretching rod 38 , between the rearward surface of canting lever 52 and an adjacent surface of stretching lever block 49 , to bias the lower portion of the canting lever 52 forwardly . with this structure canting lever 52 will bind on the stretching rod 38 to require the stretching rod move rearwardly with rearward motion of the stretching lever block 49 , but will allow free forward motion of the stretching lever block on the stretching rod responsive to motion of the stretching lever . stretching rod canting lever 55 is carried in handle chamber 21 between the forward portion of holding block 41 and the rearward surface of the handle body 18 that defines the forward surface of handle chamber 21 . this canting lever 55 is vertically elongate with medial upper hole 56 defined therein to allow free slidable passage of stretching rod 38 through the canting lever . the upper portion of the forward wall of handle body 18 threadedly carries adjustment screw 57 to extend rearwardly through the handle body and into contact with the upper portion of canting lever 55 above hole 56 to provide an adjustably positional stop to limit the forward motion of the upper part of the canting lever . compression spring 58 is carried below stretching rod 38 between canting lever 55 and the adjacent portion of holding block 41 to bias the lower portion of the canting lever 55 forwardly . with this structure the stretching rod 38 may freely move rearwardly through canting lever 55 , but the canting lever prevents forward motion of the stretching rod by binding upon the rod by reason of a slight forwardly angulated relationship thereto . the stretching rod 38 may be released from this binding action to allow forward motion of the rod through the canting lever by moving the lower portion of the canting lever rearwardly , so that the lever assumes a substantially perpendicular position relative to the stretching rod and will not bind thereon . a second species of simple band holding yoke 11a having a unitary structure is shown in fig4 . the body 9 and stretching mechanism 12 of this second species of yoke are the same as those members used with the first species 11 of yoke . the yoke 11a provides a simple unitary flat u - shaped structure defined by back 60 interconnecting similar forwardly and laterally outwardly extending legs 61 . the forward end portions of legs 61 each define curvilinear band grooves 62 extending inwardly at the forward lateral portions of the legs to define band holding portions 63 extending forwardly from the laterally inward edges of the legs . an elastic band carried by this yoke is released by manual manipulation of the tool rather than by separate mechanical release structure such as provided in the first species by yoke 11 . having described the structure of my tool , its operation may be understood . a tool of the first species of fig1 - 3 , constructed according to the foregoing specification , is provided with an appropriately constituted endless elastic band 59 . the elastomeric band 59 must be of such structure and elastic nature that when stretched about the neck of the scrotal pouch of an animal and there fastened , it has sufficient elastic force to cause ligation , and at the same time it must allow expansion sufficiently for passage of the scrotal pouch and contained testicular structure of a large mature animal such as a bovine bull through the orifice defined by the stretched band without breakage . the band must also provide sufficient material to allow fastening in a tensed condition by a deformable metallic fastening clip or similar fastening structure . normally such a band formed of natural rubber will require a cross - sectional area of approximately 0 . 1 to 0 . 4 square inch when the cross - sectional configuration is of a rectangular form . such a band normally will have a relaxed diameter of from approximately one to three inches . these parameters may vary generally with the nature of the elastomeric material and particularly for specific purposes while such bands remain operative for castration , and such variant bands are within the ambit and scope of my invention . for use of the tool , band release yoke 30 , 31 is moved to its forwardmost position and band fastening dogs 26 are rotated to a position whereat fastening lugs 29 are adjacent the associated fastening pins 34 in a position that prevents inwardly directed rotary motion of the forward portion of the band fastening dogs . with the fastening dogs 26 in this position elastic band 59 is manually placed on the band holding yoke 24 , 25 to extend between fastening grooves 28 of the opposed band fastening dogs . elastic band 59 and the band holding yoke preferably for convenience are configured so that when the band is placed between the fastening dogs it has some tension in it to create friction between the band and fastening dogs to aid positional maintenance of the band on the fastening dogs . the lower portion of canting lever 55 is then moved rearwardly to allow forward motion of stretching rod 38 therethrough and the stretching rod is moved forwardly to the elastic band 59 . one course of that band is inserted within band holding notch 39 of the stretching rod so that the band is maintained in that notch . stretching lever 46 is then manually operated with a reciprocating motion so that the rearward component of motion of the stretching lever will move stretching lever block 49 rearwardly , which in turn moves stretching rod 38 rearwardly by reason of the binding action of stretching rod canting lever 52 carried by the stretching lever block on the stretching rod . as the stretching lever 46 is moved forwardly the stretching lever block 49 will move forwardly on the stretching rod 38 because the stretching rod is prevented from forward motion by the binding force created on it by canting lever 55 . this reciprocating stretching lever motion is continued until the stretching rod is moved rearwardly a distance sufficient to create a configuration in elastic band 59 that allows placement of the band over the scrotal pouch of an animal and creates appropriate tension in the band for ligation . it is to be noted that in this stretching rod motion the band holding notch 39 and the rearward portion of the elastomeric band 59 fastened therein will be moved rearwardly through channel 17 of annular support 16 and the channel of a fastening clip 65 carried therein . the elastic band , while maintained in this stretched condition by the tool , is manually manipulated by means of the tool , and manipulation of the scrotal pouch of an animal if required , to pass the scrotal pouch and its contents through the orifice defined by the stretched band , which will be of a generally triangular shape within the yoke 11 by reason of its three point support by the yoke and the stretching rod . with the elastomeric band 59 thusly placed , it is moved to the ligation site at the neck of the scrotal pouch adjacent the animals &# 39 ; s body , and fastening clip 65 , then extending about the band at a point adjacent to the band portion about the animal scrotal pouch , is crimped to fasten the band portion about the scrotal pouch together with the existing tension in it . the band portion not about the scrotal pouch is then released from the stretching rod 38 by moving the stretching rod forewardly and rotating it appropriately if necessary to allow the release of the portion of the band from holding notch 39 . the band portion about the scrotal pouch is then released from the band holding yoke by moving the upper , rearwardly extending portion of release lever 37b downwardly to move band release yoke 30 , 31 rearwardly . the rearward motion of the band release yoke responsively moves fastening pins 34 rearwardly and out of contact with the band fastening dogs 26 to allow rotation of the forward portion of the fastening dogs inwardly toward each other by reason of the tensioned band portion extending between them and thusly releases the elastic band from the yoke . the elastic band then will be in place in position on the animal to accomplish its ligation function and the portion not about the scrotal pouch may be trimed if desired . the tool may also be removed from a placed and fastened band by releasing the band portion about the scrotal pouch from the yoke in the same fashion as described and thereafter releasing the band portion carried by the stretching rod . the placement of an elastomeric band with the second species of yoke of fig4 is accomplished in the same fashion as described for the first species of fig1 - 3 . after the band is tensioned , placed in proper position about the scrotal pouch and fastened by a clip as described , the stretching rod 38 is moved forwardly to release tension in the rearward band portion not about the scrotal pouch and the band is released from interconnection with the stretching rod . the tool then is manually manipulated by an operator to pull away from the tensioned portion of the band about the animal &# 39 ; s scrotal pouch so that the band is released from support on the forward portions of the arms of yoke 11a and remains in place to accomplish its ligation function . the foregoing description of my tool is necessarily of a detailed nature so that a specific embodiment of it might be set forth as required , but it is to be understood that various modifications of detail and rearrangement of parts might be resorted to without departing from its spirit , essence or scope .
a tool and method for continuous elastomeric band ligation type castration of larger sexually mature animals with an elastic band that must be enlarged by stretching for placement provides an elongate body having a handle at a first rearward end to aid manipulation and an elastic band supporting yoke at a second forward end . the band supporting yoke provides spaced forwardly extending legs for releasable support of the elastic band at two spaced points . band stretching mechanism carried by the body provides an elongate stretching rod that releasably interconnects one course of the elastic band carried by the yoke at a third point between the two yoke support points to stretch the band rearwardly responsive to motion of an associated compound lever mechanism to enlarge the medial orifice defined by the elastic band sufficiently to allow the band to pass over the scrotal pouch and contained testicular structure of a large animal . the elastic band is stretched rearwardly through an annular support carrying a fastening clip that is deformed about the band to maintain tension in the band portion extending about the neck of the animal scrotal pouch . release mechanism disassociates the tool from the elastic band to leave the tensioned band portion about the neck of the animal scrotal pouch at the ligation site .