US2442679A

US2442679A - Wire strapping tool

Info

Publication number: US2442679A
Application number: US576054A
Authority: US
Inventors: Harold K Embree; Burton L Watt
Original assignee: Griplock Inc
Current assignee: Griplock Inc
Priority date: 1945-02-03
Filing date: 1945-02-03
Publication date: 1948-06-01
Anticipated expiration: 1965-06-01

Description

June 1, i948. H. K. EMBREE ETAL.

WIRE STRAPPING TOOL 2 Sheets-Sheet 1 Filed Feb. 3, 1945 7 INVENTORS. /C 'M a aw M June 1, 194. H. K. EMBREE ETAL WIRE STRAPPING TOOL 2 Sheets-Sheet 2 Filed Feb. 3, 1945 Patented June 1, 1948 UNITED STATES PATENT OFFICE WIRE STRAPPDIG TOOL ration of Delaware Application February 3, 1945, Serial No. 576,054

12 Claims. (Cl. 140-93) This invention relates to a wire strapping tool designed for tensioning and fastening around packages straps composed of wire or the like; and it is particularly intended to be used in combination and cooperation with a wire strap which has been formed with one end of the wire turned back and coiled around the body of the wire so that the knot or fastening may be made by passing the other end of the wire strap through the said coil and. then crushing or flattening the coil so as to deform it and the parts of the wire strap therewithin into a firm interlocking engagement. Simultaneously with this knotting of the strap, the excess of its free end is severed, to improve the appearance of the result, and to eliminate the long end, which might present a hazard in subsequent handling and shipment.

The object of the invention is to provide certain improvements and modifications in the structure and arrangement of the tool shown in United States patent to Burton L. Watt and James J. Smith, No. 2,124,991, issued July 26, 1938, whereby facility of operation, accuracy, efficiency and durability are enhanced.

Another object is to promote economy in manufacture, ease in assembly, and simplicity in repair.

A further object is to provide certain improvements in the form, construction and arrangement of the parts whereby the above named and other objects inherent in the construction may be eiiectively attained and the general efficiency of the tool increased.

A practical embodiment of the invention is represented in the accompanying drawings, in which Fig. 1 represents a top plan view of the tool, partly broken away;

Fig. 2 represents a side elevation of the tool, partly broken away, in association with the ends of the wire strap which are in operative position preliminary to the steps of tensioning, knotting, and severing the surplus wire;

Fig. 3 represents a side elevation of the tool opposite to Fig, 2, partly broken away, with the parts in the same position as in Fig. 2 but with the wire strap omitted;

Fig. 4 represents a side elevation of the tool corresponding to Fig. 3, partly broken away, with the parts shown in the position taken immediately after the completion of the knotting and severing steps;

Fig. 5 represents an end elevation of the tool, partly broken away, with the parts in the position shown in Fig. 3;

Fig. 6 represents a detail section taken in the plane of the line VIVI of Fig. 5, looking in the direction of the arrows;

Fig. '7 represents a detail side view with parts removed to expose the crushing or knotting and severing or cutting elements; and

Fig. 8 represents a detail horizontal section taken in the plane of the line VlII-VIII of Fig. '7, looking in the direction of the arrows.

The tool which constitutes the subject matter of this invention is of that class designed for cooperative use with wire straps such as hereinabove described, in order rapidly and securely to bind packages which may consist of a group or pile of separate articles, or a container in which articles have been placed, or any other form of package around which it is desired firmly to clasp a binding element. The tool is adapted to be associated with a package around which such a wire strap has been loosely placed, and it includes mechanism for thereupon tensioning or binding the strap, and thereafter deforming the coiled end and contacting parts of the strap by a crushing pressure to form the desired knot which fastens the strap in its tensioned condition, with simultaneous severing of the excess or surplus end of the strap.

Those portions of the strap which cooperate with and are acted upon by the tool are shown in Fig. 2, where the body of the strap is denoted by A; its coil by B; and its end, which is passed through the coil for knotting and subsequent severing of the excess, is marked C. It will be understood that the broken away part of the strap which is not seen in the figure consists of the main body thereof which has been passed around the package before the tool has been placed in operative position.

To a substantial extent the main elements of the tool are similar in form, arrangement and operation to corresponding elements disclosed in; the above named Patent No. 2,124,991 and, as the Said elements, their mutual arrangement, and operation are fully shown and described in the said patent, and to that extent constitute no part of the present invention, the present description will not go into detail with respect thereto but will rely upon reference to said patent as an adequate disclosure thereof. However, the elements will be identified by name and general function and numbered to correspond with said patent in order to establish a background for detailed description of the present inventive features.

The tool comprises a base I which has inte rally formed therewith an uprising web 2 which forms.

a support for a head 3 that provides a housing and bearings for certain of the operative elements.

The gripping mechanism which seizes the body A of the wire at a point adjacent the coil B dur ing the tensioning step, includes a serrated law 4 which is secured to the side of base I by screws such as 5, and cooperates with a movable jaw 6 which is arranged to be slid into and out of operative relationship with respect to the fixed jaw 4 by an arm l9 that is controlled by a hand lever l9 and slidable rod 28, as isfully described in said Patent 2,124,991. 7 V

A tensioning hub 2i is journaled in'extensions 22 and 23 that are integral with and connect the base I and head 3; the said hub 2| being secured in position by nut 24 which is threaded, onto an end thereof. The said hub 2| is provided with teeth 46 that project laterally from: the face thereof and are intended to receive between them the free end C of the wire strap, which latter also passes through a hook 31 which is carried by the moving jaw 6 and located intermediate the tensionin hub 2| and the point at which theknotting and'severing of the strap takes place; said hook serving the purpose of urging the strap into engagement with the teeth 46 on hub 2 I.

Secured to the hub 2! is a ratchet wheel 2:: which is actuated by a pawl 41 that is carried by the hand lever l9, and held against opposite motion by another pawl 48 fixed on the web 2. The result of the'arrangement just described is that manual reciprocation of the hand lever is will at first cause the jaws 4 and 6 to grip the portion A of the wire strap, and thereafter tension the said strap around the package by rotation of the hub 2| with the teeth of which the free end of the wire strap is engaged; all as more fully and in detail described in said Patent No. 2,124,991.

It is the customary practice for the operator to pass the wire strap loosely around the package to be bound and lead the free end C through the coil B. Thereupon, the tool is placed upon the package and moved at first laterally and then to the left (Fig. 2) with respect to the strap; following which the free end C of the strap'is passed through the hook 31 and engaged with the teeth :36 on the tensioning hub- 2|. The parts are now in the position illustrat ed in Fig. 2 and the tensioning operation already described may proceed, following which it is in order to knot the tensioned strap by a crushing or deforming operation and, simultaneously therewith, to sever the excess wire.

The crushing or deforming of the coil B and V contacting parts of the strap is accomplished by depressing a crushing block 62 which is directly actuated by a pair of thrust bars 60, 6| withwhich the block 62 is held in contact by a re tractile coil spring 63, one end of which is fastened to the block and the other end to the head 3 of the tool. A spacing leaf spring 64 is sus' pended from the fastening point of spring 63' in the head 3 and arranged so that its free ends engage the inner sides of thrust bars 68, 6| in order yieldingly to urge them apart and steady. them during operation.

Manually operated

crushing levers

53, 54 have their inner ends curved and mounted on a pair of similarshafts 51, 51 to which the said levers are keyed. The said shafts 51 are formed with

eccentric portions

59, 59 which contact the thrust bars 60, BI and serve to depress ands 4 elevate the crushing block 62 as the

levers

53, 54 are moved in one direction or the other. Theconstruction, arrangement and operation of the crushing block 62 and associated parts, to whichbrief reference has just been made, are set forth' in detail in said Patent No. 2,124,991; so thatfurther description herein is regarded as unnecessary.

The manually operated

crushing levers

53, 54 have intermeshing partial gears 69, 79 formed on their inner ends, which gears compel the said levers to operate in unison and, in effect, increase or compound the crushing force exerted thereby. While, for the sake of simplicity in description, thesame reference numerals have been applied to thesaid gears herein shown as to the gears on levers 5,3 and 5- 3 of Patent 2,12%,991, there is a marked and important difference between the gears of the present application and those of the patent in both form and function; the said difference residing chiefly in the provision of smaller and more numerous teeth on the gears in the present tool, which constitutes a substantial improvement and forms part of the present invention.

It will be appreciated that the crushing or knotting operation of the tool must be very precise and exact and that it is essential to avoid variation in the same such as might arise, for instance, from human fatigue or other vicissitudes of frequently repeated day in and day out operation. The movement of the crushing block to establish the knotting effect is slight and its function must be completely and evenly performed at each manipulation of the tool if the strap is to be securely bound around the package and be able to Withstand not only the constant strain of the tension which has been placed upon it but also the inevitable stresses and blows during loading, transportation, unloading and delivery. To this end, it is of prime importance to increase or enhance the capacity of the tool for substantially perfect and uniform functioning in the hands of operators varying in skill, physical strength, care, fatigue, etc. In other words, an increase in the extent to which the human equation is eliminated greatly enlarges the utility and value of the tool.

This invention takes account of the foregoing and notably promotes the attainment of the desired resultby establishing the interengagement of the crushing levers 53, 54 through a comparatively large number of comparatively small teeth on the partial gears 65!, Hi. In actual practice the pitch diameter of said gears is approximately an inch and a half and I have discovered and demonstrated that teeth of a size such as would re quire eighteen for a complete gear of that pitch diameter are particularly and almost ideally effective in enabling operators of different characteristics and under different circumstances to manipulate the tool without undue effort and with almost flawless uniformity and precision. A substantially smaller number of, and hence larger, gear teeth increases the manual power required for actuating the tool, and gives rise to greater chance for wear and lost motion which, of course, tends to lead to variation in the stroke and functional effect of the crushing block; while, on the other hand, a substantially greater number of, and hence smaller, gear teeth offers an increased danger of breakage and frictional resistance in operation. Teeth of such relative or proportional size and pitch as represented by a gear of an inch and a half pitch diameter with eighteen teeth have been found to be critically effective and to import very beneficial results without offsetting disadvantages. These are known in the trade as number twelve pitch teeth, and the provision thereof in this tool has greatly increased its practical advantages and commercial value.

In order to operate the crushing block 52 for forming the knot, the operator seizes the

levers

53, 54 and moves them from the position indicated in iF'ig. 3 toward the position indicated in Fig. 4. This movement of the said levers rotates the shafts 51, 51 and causes their

eccentric portions

59, 59 to depress the thrust bars 5t, 6| and, hence, the crushing block 62, which latter flattens or crushes the coil B of the wire strap and corrugates the adjacent portions of the wire in order to form the knot, as hereinabove described.

The tool includes adjustable means for limiting the movement of the

levers

53, 54 in depressing the crushing block 52 and thereby insuring attainment of the predetermined extent of movement of the block and hence the desired result in formation of the knot. The said means constitutes one of the features of the present invention and will now be described.

levers 53, 54 firmly contact the stop at the limit of their operative movements. Separate, individually adjustable stops for the

levers

53, 54 could not afford this facility, and any inaccuracy in their adjustment might give rise to an undesirable condition in which one of the levers encountered a stop while the other was free for further movement; thereby unfavorably affecting the mechanical operability of the tool as well as its functional accomplishment.

The outer face of the housing 89 has an arch shaped socket 89 formed therein which serves as a finger grip for the operator in transporting the tool, moving it into and out of operative position, and during actuation of the lever 19 in the tensioning step. This advantage is heightened by the curved formation of the said face of the housing, as indicated at 90.

The housing not only serves the purposes hereinabove described, but also acts as a guard or shield for certain of the movable parts of the tool mechanism. It may conveniently be composed of aluminum, or the like, for the sake of lightness; and affords a desirable surface area A housing -35 is secured on the base I by a pair 7 serves to vary the extent of its protrusion from the sleeve. The headless screw 84 may be turned so as to contact the inner end of the screw 83 in any position of the latter in order to lock it against unintentional movement. The sleeve 82 has a circumferential groove 85 formed in its outer periphery which is fitted to receive a looking pin 96 which has a driven fit in a hole formed in the housing 99 and extends transversely with respect to the sleeve 82. This locking pin prevents removal of the sleeve from the housing but does not prevent a limited endwise movement of the former in the latter because the groove 85 has an axial length considerably greater than the diameter of the pin 86.

The

levers

53, 54 have

shoulders

81, 88 formed on their inner ends near the partial gears 69, 10 and, when the said levers are swung to the position shown in Fig. 4 for the purpose of depressing the crushing block 62 and forming the knot, the said shoulders contact an end of sleeve 82 and the head of screw 83, respectively, thus limiting the movement of the

levers

53, 54 and thereby terminating the downward stroke or depression of the crushing block 62. By adjusting the screw 83 in the sleeve 82, the extent of movement of

levers

53, 54 can be varied, which will likewise and correspondingly vary the travel of crushing block 62; whereby the operator can minutely adjust the functioning of the tool with the utmost precision.

An importantfeature of this adjustable stop assembly resides in the fact that it is axially movable to a slight extent in the housing 80 because the groove 85 is greater in length than the cross section of the locking pin 86. This capability permits a slight differential in the extent of movement of the lever 53 with respect to the lever 54 without at all affecting the result of the combined movement of the said levers in depressing the crushing block 62; and it also insures that both for trade-mark, serial number, and the like.

As previously mentioned, the formation of the knot in the strap by the crushing action of the block 62 is accompanied by severing of the excess free end C of the strap; and the arrangement and timing of the parts is such that the severing or cutting takes place just prior to the completion of the downward stroke of the block 62, but not until the last named action has interlocked the ends of the strap sufiiciently to prevent slippage.

This severing is accomplished by a cutter composed of male and female members, the male member 9| being mounted in the lower part of the crushing block 52, and the female member 92 being set in a hole 93 that is formed in an anvil plate 94 fixed on the base of the tool and extends through the base. The said anvil plate is preferably composed of hardened metal to resist the crushing action of the block 92. The male member of the cutter may be of any well known and approved'form suitable for cooperation with the female member, and is preferably composed of hardened steel of such composition and temper as is well adapted for its function. The female member 92 of the cutter is centrally bored and has an enlarged head 95 which is set flush in the anvil plate 94. The inner circumference or periphery of the female member formed by the bore therein provides a cutting edge complementary to the male member, and the said cutting, edge may, in effect, be renewed from time to time by adjustment of the female member in a rotary or circumferential direction. The said female member is also composed of hardened steel, or the like, of suitable composition and temper for its purpose, and has a driven fit in the anvil plate 94 and base a l of the tool, and its rotary adjustment may be accomplished, when desired, by inserting a suitable tool into the hole 93 and loosening the said memher for such adjustmennafter which the member may be driven back to its operative seat. This adjustability enables the cutter to maintain its full efliciency for an extended period of time, and is a meritorious feature of this tool construction.

It will be understood that the depression of crushing block 62 by actuation of the hand levers 53, 54, likewise depresses the male member 5! of the cutter so as to cause it to enter the female member 92 and sever the excess end C of the strap. This same actuation of the

levers

53, 54

also serves to separate the jaws 4 and 6 and therebyrelease the grip of the tool on the main body Aof the strap. As the means for and manner of accomplishing this separation of the said jaws isfully set forth in said Patent 2,124,991 and forms no part of the present invention, the same will not be further described herein. However, it should be noted that the parts involved in this step should be arranged and adjusted so that the opening of the jaws 4, 6 and their releasing of the body A of the strap occurs simultaneously with thecompletion of the crushing or knotting operation; because, if the grip of the jaws 4, 6 were released too early in the cycle of operations, there might be loss of tension in the strap due to slip page before complettion of the crushing or knotting step. On the other hand, if the jaws 4, 6 should not release the strap concurrently with completion of the formation of the knot, the intended operation of the tool might be handicapped or defeated.

Features of substantial merit and improvement in the tool embodying the present invention include the comparative size, pitch and number of the teeth 69, m on the

levers

53, 54; the provision and form of the housing 80; the provision, construction, arrangement and function of the adjustable stop unit having the sleeve 82; the form, arrangement and relative adjustability of the cutter elements 9!, 92; and the form and manner in which the said features of novelty and advantage are embodied in and arranged with the other parts of the tool.

Inasmuch as the function and operation of the several parts of this tool have been set forth in connection with their particular description herein, and of the further fact that the operation of the tool as a whole is similar to that described in the above named Patent 2,124,991; it is regarded as not requisite here to set forth a detailed recital of the operationaluse of the tool.

We desire it to be understood that various changes may be resorted to in the form, construction, arrangement, and material of the several parts without departing from the spirit and scope of our invention, and hence do not intend to be limited to the details herein shown and described except as they may be included in the claims or required by disclosures of the prior art.

What we claim is:

1. In a device of the character described, a plurality of levers arranged for coincidental actuation, a support for said levers, and a stop mounted on said support and adapted to have its ends contacted by said levers to simultaneously limit their operative strokes, said stop comprising elements adjustable with respect to each other to vary the effective length of the stop.

2. In a device of the character described, a plurality of levers arranged for coincidental actuation, a support for said levers, and a stop mounted on said support and adapted to have its ends contacted by said levers to simultaneously limit their operative strokes, said stop comprising elements adjustable with respect to each other to vary the effective length of the stop, said stop also being bodily movable endwise upon contact by said levers to permit a differential in the extent of operative stroke of one lever with respect to another.

3. In a device of the character described, a plurality of levers arranged for coincidental actuation, a support for said levers, and a stop mounted on said support and adapted to have its ends contacted by said levers to simultaneously limit their operative strokes, said stop comprising elements adjustable with respect to each other to vary the effective length of the stop, saidstop also being bodily movable endwise in either direction upon contact by either of said levers to permit a differential in the extent of operative stroke of either lever with respect to another.

4. In a device of the character described, a support for operative elements, a pair of levers pivoted on said support for manual actuation, a housing mounted on said support below said levers, and a stop carried in said housing and located in the plane of movement of said levers, said stop being adapted to be contacted by said levers to limit their operative strokes.

5. In a device of the character described, a support for operative elements, a pair of levers pivoted on said support for manual actuation, a bored housing mounted on said support below said levers with its bore located in the plane of movement of said levers, and a stop slidably fitted in the said bore, said stop being adapted to be contacted by said levers to limit their operative strokes while permitting a differential in the extent of the operative stroke of each lever with respect to the other.

6. In a device of the character described, a support for operative elements, a pair of levers pivoted on said support for manual actuation, a bored housing mounted on said support below said levers with its bore located in the plane of movement of said levers, and a stop adjustable in length slidably fitted in the said bore, said stop being adapted to be contacted by said levels to limit their operative strokes while permitting a diiferential in the extent of the operative stroke of each lever with respect to the other.

'7. In a device of the character described, a support for operative elements, a pair of levers pivoted on said support for manual actuation, a bored housing mounted on said support below said levers with its bore located in the plane of movement of said levers, a stop adjustable in length slidably fitted in the said bore, said stop being adapted to be contacted by said levers to limit their operative strokes While permitting a differential in the extent of the operative stroke of each lever with respect to the other, and means for limiting the movement of the stop in the housing.

8. In a device of the character described, a support for operative elements, a pair of levers provided with intermeshing gears pivoted on said support for manual actuation, a bored housing mounted on said support below said levers with its bore located in the plane of movement of said levers, and a stop slidably fitted in the said bore, said stop being adapted to be contacted by said levers to limit their operative strokes while permitting a differential in the extent of the operative stroke of each lever with respect to the other.

9. In a device of the character described, a support for operative elements, a pair of levers provided with intermeshing gears pivoted'on said support for manual actuation, a bored housing mounted on said support below said levers with its bore located in the plane of movement of said levers, and a stop adjustable in length slidably fitted in the said bore, said stop being adapted to be contacted by said levers to limit their operative strokes while permitting a diiferential in the extent of the operative stroke of each lever with respect to the other.

10. In a device of the character described, a support for operative elements, a pair of levers pivoted on said support for manual actuation, a housing mounted on said support below said levers, and a stop carried in said housing and located in the plane of movement of said levers, said stop being adapted to be contacted by said levers to limit their operative strokes, and said housing serving as a guard for operative elements and as a finger grip for manual handling of the device.

11. In a device of the character described, in combination with a strap having a coiled end which is intended to be crushed and itself to deform the other end of the strap for securing the strap around a package, mechanism for crushing said coiled end for said purpose, said mechanism including a plurality of levers arranged for coincidental actuation, a support in which said levers are pivoted, and a stop comprising elements adjustable with respect to each other to vary its effective length, said stop being slidably mounted on said support for endwise bodily movement and being in position to have its ends contacted by said levers when actuated about their pivots to simultaneously limit their operative strokes.

12. In a device of the character described, in combination with a strap having a coiled end which is intended to be crushed and itself to deform the other end of the strap for securing the strap around a package, mechanism for crushing said coiled end for said purpose, said mechanism including a plurality of levers arranged for coincidental actuation, a support in which said levers are pivoted, and a stop comprising elements adjustable with respect to each other to vary its efiective length, said stop being slidably mounted on said support for endwise bodily movement and being in position to have its ends contacted by said levers when actuated about their pivots to simultaneously limit their operative strokes, said levers having interengaging gear teeth to cause them to operate in unison, said teeth being of approximately the pitch size embodied in a gear having a pitch diameter of one and one-half inches and eighteen teeth.

\ HAROLD K. EMBREE.

BURTON L. WATT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 205,527 Cohen July 2, 1878 477,066 Root June 14, 1892 490,777 Trethewey Jan. 31, 1893 496,902 Root May 9, 1893 1,401,025 Wright Dec. 20, 1921 1,776,868 Stratton Sept. 30, 1930 1,854,254 Gray Apr. 19, 1932 1,970,589 Wright Aug. 21, 1934 1,977,795 Gray Oct. 23, 1934 2,033,581 Malinge Mar. 10, 1936 2,124,991 Watt et a1 July 26, 1938 2,239,445 Martin et a1 Apr. 22, 1941 2,247,776 Gerrard July 1, 1941 2,251,087 Vincent July 29, 1941 2,348,265 Rippingile May 9, 1944