US1982076A - Lock washer - Google Patents

Description

Nov. 27, 1934. c. .1. SPAHN 1,982,076

LOCK WASHER Filed April 10, 1934 mi "u INVENTOR C. J. S/JCt/ZIZ- ATTORNEY Patented Nov. 27, 1934 UNETED STATES LOCK wssmm Chester J. Spahn, Folsom, Calif., assignor of onehalf to James H. Cavitt, Folsom, Calif.

7 Application April 10, 1934, Serial N 719,865

1 Claim.

This invention relates to lock washers for bolts, and particularly for button head carriage bolts such as are used in connection with wooden parts and which are prevented from turning in the wood by the squared shank portion immedi ately under the head and driven into the wood.

It sometimes happens however, especially when the bolts are drawn up tight, when in soft wood, or when the bolt hole is relatively large and provides little stock for holding engagement with the spared portion, that the bolts turn or the heads become drawn into the wood. This either prevents the proper tightening up of the nut or in the event of the head ultimately drawing into the wood, causes the parts tied together by the bolt to become loose relative to each other.

The principal object of my invention therefore is to eliminate these undesirable occurrences by the provision of a simple and inexpensive form of lock washer for bolts of this character designed to both positively prevent rotation of the bolt and also the drawing of the head of the same into the wood.

The above object I attain by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claim. 1

In the drawing similar characters of reference indicate corresponding parts in the several views:

Figure 1 is a diametral section of a washer as applied about a carriage bolt shown mounted in connection with a wooden beam.

Figure 2 is a perspective view of a two-prong washer.

Figure 3 is a similar view of a three-prong washer.

Figure 4 is a similar view of a modified form of washer.

Referring now more particularly to the characters of reference on the drawing, the type of bolt to which my improved washer is designed to be applied comprises a shank 1 having a button head 2 and a square portion 3 immediately under the head whose width across the flatsis thesame as the diameter of the shank, so that the corners of said portion project beyond the periphery of the shank for engagement with the wood 4 outwardly of the bolt hole 5.-

The washer as shown in Figures 1 and 2 comprises a circular body 6 larger than the bolt head having a square hole 7 tofit the shank portion 3. Depending from the body at opposed points outwardly of the periphery thereof and at an outward angle to the axis of the bolt and washer 4 also to the turning of the same.

are stiff sharp pointed prongs 8. These draw into the wood as a longitudinal pulling pressure is placed on the bolt and prevent the bolt from turning without relying on the'engagement of the squared portion 3 with the wood. The angular setting of the prongs relative to the direction of axial movement of the washer, and the placing of the same outwardly of the periphery of the body of the washer adds to the resistance of movement of the washer into the wood and A bolt equipped with a washer of this character therefore is practically held immune from any rotative or axial movement once the nut has been properly. tightened. v

The construction in Figure 3 is the same except that the washer body 6a has three evenly spaced prongs 8a; this type of washer being preferably used in connection with relatively large bolts or where the wood is quite soft.

The type of washer disclosed in Figure 4 is the same generally as either of the above described types, but instead of the prongs the washer body 6b has a plurality of short spikes 9 depending therefrom inwardly of the periphery of the body and in evenly spaced relation about the bolt opening asplainly shown.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail th present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claim;

Having thus described my invention what I claim as new and useful and desire to secure by

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