US902763A - Wire-stretcher. - Google Patents

Description

S. S'. ROBERTS.

WIRE STRETGHER.

APPLICATION FILED MAR. 27, 190B.

Patented Nov. 3, 1908.

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THE NORRIS PE Rs co STEPHEN S. ROBERTS, OF MEXICO, MISSOURI.

WIRE-STBETCHER.

Specification of Letters Patent.

Patented Nov. 3, 1908.

Application filed March 27, 1908. Serial No. 423,728.

To all whom it may concern:

Be it known that I, STEPHEN S. RoBER'rs, a citizen of the United States, residing at Mexico, in the county of Audrain, State of Missouri, have invented certain new and useful Improvements in VVire-Stretchers; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to improvements in wire-stretching devices, and it has for its primary object the provision of an exceedingly simple, readily operated and comparatively inexpensive device for simultaneously stretching two wires extending in opposite directions from a pair of relatively adjacent fence posts.

To this end, the invention resides in the provision of a casing or shell supported upon a horizontally-(lisposed strap adapted to be secured to one of the posts, the casing carrying a power shaft upon which a sprocket wheel and a ratchet wheel are mounted, the first mentioned wheel operatively engaging a pair of sprocket chains which extend in opposite directions and are provided at their outer ends with gripping devices for engaging the wires.

The invention further resides in the provision of a spring pressed pawl which normally engages the ratchet wheel to prevent retrograde movement thereof, but which is adapted to be raised bodily out of engagement with said wheel to permit such movement thereof for returning the chains to their initial position.

The above mentioned and other features will be readily understood from a consideration of the following detailed description, their preferred embodiment being illustrated in the accompanying drawings, in which corresponding parts are designated by the same reference numerals throughout the several views.

Of the said drawings: Figures 1 and 2 are respectively, front and rear elevations of the complete invention. Fig. 3 is an enlarged vertical section through the stretcher. Fi 4 is a plan view of the stretcher.

Referring more particularly to the drawings, 7 designates generally the stretching device; 8 the support therefor, which support is attached to the post 9, as hereinafter described; and. 10 and 11 the oppositely-extending wires which are engaged by the stretcher and cross the post 9 above referred to and the second post 12 adjacent thereto.

The support 8 which carries the stretcher consists, as shown, of a flat horizontally-disposed metal strap 13, to the end of which adjacent the post 9, is secured a rotatable key 14: provided with a ratchet 15 and a sprocket 16, the former of which is engaged by the laterally-bent end of a dog 17 which is likewise secured to said strap. The sprocket carried by said key engages a sprocket chain 18 adapted to be looped around the post 9, one end of the sprocket chain carrying a barbed hook 19 adapted to be driven into the post. By reason of this construction, it is possible, upon rotating the key 14, to tighten the sprocket chain around the post, thus cooperating with the brace rods 20 with which the strap 13 is provided, in retaining the support as a whole in proper position. The specific construction of the support however, forms no positive part of the present invention, inasmuch as it will form the subject of a separate application to be hereinafter filed.

The stretching mechanism which is supported as stated by the devices described above, comprises a hollow shell or casing 21, whose back has formed thereon upper and lower pairs of spaced cars 22, while its front edge is provided with an integral tongue 28, which projects forwardly for a slight distance and is then bent downwardly, said tongue being provided with a perforation which alines with a perforation formed centrally in the back of the casing, through which perforations extend the ends of the power shaft 24., the squared front end of which carries a crank handle 25, by means of which its rotation is efiected. The pairs of ears 22 above referred to engage the upper and lower edges of the strap 13 as shown in Fig. 2.

Secured to the power shaft and. located interiorly of the casing are a ratchet wheel 26 and a sprocket wheel 27, the latter wheel operatively engaging at diametrically-opposite points a pair of sprocket chains 28 and 29, whose outer ends are provided with gripping devices 30 for engagement with the wires 10 and 11. It will be apparent from the foregoing, therefore, that when the power shaft is rotated in one direction, the gripping devices will be drawn towards each other, thus stretching the wires with which they are engaged, backward rotation of the shaft during such operation being prevented by the engagement with the ratchet wheel, of a dog 33, which is normally held in operative position by a coil spring 84. The dog extends through alining openings formed in the top of the casing and in an ear 85 which projects laterally from one side of an upwardly extending post 36 mounted upon the casing and formed integral therewith, the upper end of the dog being pivotally connected with the cam head of a lever 37, the cam head resting against the ear 35 under the action of the coil spring. The dog can therefore, be raised bodily into inoperative position by a movement of the cam lever, as will be understood, whereupon the backward rotation of the power shaft incidental to returning the sprocket chains to their initial position, at the completion of the stretching operation, is possible. The opposite side of the post 36 is provided likewise with a laterally-projecting ear 38 which serves as a support across which the stretched wire or wires are passed prior to the return movement above referred to of the sprocket chains, the wires being engaged by the serrated cam face of a lever 39 pivoted to the post slightly above said ear. The provision of this lever, as will be apparent, prevents the stretched wire or wires from becoming loosened when the gripping devices carried by the chains are released from engagement with the wires, and the dog from engagement with the ratchet wheel, both of which operations take place prior to the movement of the chains away from each other to their initial position and the subsequent reengagement of the gripping devices with the wires. The inner ends of the chains are provided with rings 40, or similar stops, which. prevent the complete passage of the chains through the casing and their consequent disengagement from the sprocket wheel.

That is claimed is 1. In a wire stretching device, the combination, with a casing, of a power shaft mounted in the casing; a sprocket wheel secured to said shaft; a pair of oppositely-extending sprocket chains operatively engaged with said sprocket wheel; a wire-gripping device secured to the outer end of each chain; and means for rotating said shaft, to draw said gripping devices simultaneously towards said sprocket wheel and stretch the wires.

2. In a wire stretching device, the combination, with a casing, of a power shaft mounted in the casing; a sprocket wheel and a ratchet wheel secured to said shaft interiorly of the casing; a pair of oppositelyextending sprocket chains operatively engaged with said sprocket wheel; a wire-gripping device secured to the outer end of each chain; means for rotating said shaft in one direction, to draw said devices simultaneously towards the sprocket wheel; means normally engaged with the ratchet wheel, for preventing rotation of said shaft in a backward direction; and means for bodily disengaging said last-mentioned means from said ratchet wheel, to permit such backward rotation.

3. In a wire stretching device, the combination, with a casing, of a .power shaft mounted in the casing, a sprocket wheel and a ratchet wheel secured to said shaft interiorly of the casing; a pair of oppositelyextending sprocket chains operatively engaged with said sprocket wheel; a wire gripping device secured to the outer end of each chain; means for rotating said shaft in one direction to draw said devices simultaneously towards the sprocket wheel; a springpressed dog normally engaged with the ratchet wheel, for preventing backward rotation of said shaft; and means for bodily disengaging said dog from said ratchet wheel, to permit such backward rotation.

4. In a wire stretching device, the combination, with a casing, of a power shaft mounted in the casing; a sprocket wheel and a ratchet wheel secured to said shaft interiorly of the casing; a pair of oppositely-extending sprocket chains operatively engaged with said sprocket wheel; a wire-gripping device secured to the outer end of each chain; means for rotating said shaft in one direction, to draw said devices simultaneously towards the sprocket wheel; a springpressed dog normally engaged with the ratchet wheel, for preventing backward rotation of said shaft; and a cam lever pivotally connected with said dog, for bodily withdrawing the same from engagement with said ratchet wheel to permit such backward rotation.

5. In a wire stretching device, the combination, with a casing, of a power shaft mounted in the casing; a sprocket wheel and a ratchet wheel secured to said shaft interiorly of the casing; a pair of oppositelyextending sprocket chains operatively engaged with said sprocket wheel; a wire-gripping device secured to the outer end of each chain; means for rotating said shaft in one direction, to draw said devices simultaneously towards the sprocket wheel; means normally engaged with the ratchet wheel, for preventing rotation of said shaft in a backward direction; means for bodily disengaging said last mentioned means from said ratchet wheel, to permit such backward rotation; and a separate gripping device for engaging the stretched wiires during the backward rotation of said shaft.

6. In a wire stretching device, the combination, with a casing, of a power shaft mounted in the casing; a sprocket wheel and a ratchet wheel secured to said shaft interiorly of the casing; a pair of oppositelyfrom said sprocket wheel, to permit the backward rotation of said shaft; and a separate gripping device carried by said member for engaging the stretched wires during the backward rotation of said shaft.

M In testimony whereof, I my signature, in presence of two witnesses.

STEPHEN S. ROBERTS.

l Vitnesses R. N. ARMSTRONG, E. S. CLEVELAND.

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