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Publication numberUS164100 A
Publication typeGrant
Publication dateJun 8, 1875
Filing dateFeb 25, 1875
Publication numberUS 164100 A, US 164100A, US-A-164100, US164100 A, US164100A
InventorsSebastiah Plymale
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Improvement in dynamic wrenches
US 164100 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)


Dynamic Wrench.

* Pat entedjune 8,l875.

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Specification forming part of Letters PatentNo. 164, 100, dated June 8,-1875 application filed February 25, 1875.

To all whom it may concern:

Be it known that I, SEBASTIAN PLYMALE, of Portland, in the county of Multnomah, in the State of Oregon, have invented an Improvement in Dynamic Wrenches, of which the following is a specification:

My invention consists in the application of certain levers, springs, 850., 'to a movable ratchet held in the case of a wrench and consists, substantially, of the parts represented in the drawings by Figs. 1 and 2.

Figurel shows a section in a lateral and longitudinal manner through the middle of the wrench-case, and Fig. 2 shows the exterior of the same with the indicator, dial, 850.

The ratchet A has in its center a square five or six side mortise, corresponding to the bolthead or nut to be used. The ratch-cuts do not run entirely across the face of the piece A, but are made in such a way that a web'is left on either edge, forming a cylindrical bearing, and fitting into the case J neatly, or in such a way that it may turn freely in it when a vibratory motion is given it by the handle screwed into the smaller end; also, in the piece A a number of small round holes are bored, into which the pin M fits for certain uses. B is a pawl, whose back end forms a fulcrum, against which one end of the lever D works, and is connected to D by'a link, 0. In the larger end ofD a short rock-shaft-isformed in the solid casing, whose ends are held by the wrench-case J, and at the smaller end of D a second fulcrum, E, is placed loosely between the levers D and F. The circumferential end of F isformed into a circular rack, which engages with the index-pinion G.

The weighing-spring H presses the whole system of levers and fulcrums firmly together and against the adjusting-screw L. In addition to these a small U-shaped spring is used to press the pawl B into theratch. By means of these parts the index p ipion G gives motion to the indicator on the face of the dial I, Fig. 2.

The screw L is used to set the indicator at any given number of pounds, when the wrench is used as an ordinary wrench, until the pressure becomes great enough to move the indicator. As soon as this is noticed the opera tion of turning the nut ceases, as it shows that the desired tension on the bolt has been reached.

The strength of the spring H is ascertained by experiment, and the dial I graduated accordingly.

Simply turning the screw L compresses the spring H, and at the same time turns the indicator, showing the number of pounds represented by the compression, and, as a matter of course, the'force represented in turning the handle of the wrench, and communicated through the pawl B to the ratch A, is instantly registered, when the force used in turning becomes greater than the influence of the spring H acting against the levers F and D.

Screws K hold the face of the case on.

This wrench is useful wherever nuts and screws are used, as, by means of it, bolts may be made to carry a uniform load, and the exact weight or pressure they are holding ascertained in pounds; more especially useful in the case, of suspension rods of bridges,- roofs, and suspended structures; for ascertaining the strain on cables attached to screws, orcapstans fitted for this purpose.

When it is desired to fix the ratch A firmly in the case J, the pin=M is inserted in one of the holes in ratch A, and turned partially round, or until a groove cut across the pin looks it fast behind the wire N To unloose it the operation is reversed, and a spiral spring around the pin M, and between the milled head of M and the wrench-case, returns it to its first or unengaged position.

The wear of any of the parts will not essentially interfere with the weighing apparatus, as all such wear is compensated by means of the spring H and the screw-pin L, against which the system bears.

I claim- The ratch A, pawl B, link 0, levers D and F, fulcrum E, spring H, screw L, and pin M, operating in a case, J, on an indicator, G, over a dial, I, substantially as described, and for the purpose set forth.



GHAs. B. TALBOT, Rrcnn. M. TABon.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2417402 *Sep 29, 1944Mar 11, 1947Apco Mossberg CompanyRatchet torque screw driver
US2529947 *Nov 22, 1946Nov 14, 1950Johnson Richard AClutch-head torque indicating wrench
US2838270 *Sep 8, 1952Jun 10, 1958All Power Mfg CoHandle structures for valves and the like
US7320254Sep 7, 2005Jan 22, 2008Wendell MartinHand-held torque measuring device
Cooperative ClassificationB25B23/1427