US2620838A - Quick-acting holding block for peening gauge strip employed in shot peening processes - Google Patents

Description

Dec. 9, 1952 R. B. HUYETT ET AL 2,620,833

QUICK-ACTING HOLDING BLOCK FOR PEENING GAUGE STRIP EMPLOYED IN SHOT PEENING PROCESSES Filed Jan. 27, 1948 Patented Dec. 9, 1952 QUICK-ACTING HOLDING BLOCK FOR PEENING GAUGE STRIP EMPLOYED IN SHOT PEENING PROCESSES Robert B. Huyett, Hagerstown, Md., and Frank Newell, Chicago, Ill., assignors to Pangborn Corporation, Hagerstown, Md., a corporation of Maryland Application January 27, 1948, Serial No. 4,518

2 Claims.

This invention relates to holding blocks for peening gage strips and has for its principal object the provision of a quick acting block adapted in a single movement to clamp a peening gage strip securely to its face and in a single reverse movement to positively release the same.

Other objects and advantages of the invention will be apparent from the description hereinafter of a preferred embodiment exemplifying the invention.

The invention consists in the novel arrangements and features of construction hereinafter described and claimed.

In blast peening operations metal shot or the like is projected at high velocity against the surfaces of metal parts or sheets to improve the surface characteristics thereof. In such operations it is necessary to make periodic tests to determine that the character and quantity of the shot, and the force of impingement thereof, are so related as to impart the correct degree of peening treatment in the time allotted to the peening operation. For this purpose tests are made by subjecting standard test strips such as the Almen Peening Test Strip to the action of the peening blast. In such tests the strip is secured to a flat supporting block and passed once through the blast stream. The hammering effect of the shot on the strip increases the density of its surface and when the strip is released it is found to be deflected from its original flat form into an arc. The measure of the height of the resulting arc is a measure of the blasting intensity.

In blast peening operations as many as fifteen such intensity tests are made per hour. Each test requires the mounting of the test strip on its supporting block and its subsequent removal therefrom.

The test-strip blocks conventionally used have comprised a solid steel block by 1 /2" by 3", hardened. These blocks were drilled with four holes, and four 1%" X /8" round headed stove bolts were passed freely through the holes and provided with nuts on their projecting ends. The mounting and unmounting of the strips thus required tightening and loosening the nuts on these four bolts, while holding them by means of a screw driver inserted in their head kerfs. Aside from this, the peening operation in a short time hammered down the kerfed heads of the bolts to an extent at least rounding oil, and frequently closing, the kerfs therein so they could no longer be successfully engaged with a screw driver blade. Also the nuts were frequently dropped and lost,

and the bolts frequently Ibecame frozen into the block by dirt or as a result of the peening action, and were difficult to loosen therefrom. The use of these conventional blocks was therefore accompanied by much loss of time and required frequent replacement of the nuts and bolts therein.

The new strip holder provided by the present invention in its preferred form requires no disassembly in securing and freeing the strip, and eliminates the other difficulties of the conventional strip holder.

In the illustrative embodiment of the invention disclosed in the drawings forming a part of this specification:

Figs. 1 and 2 are back-face and front-face views of a preferred form of the new holder with the peen strip in place thereon,

Figs. 3 and 4 are plan and side views thereof,

Figs. 5 and 6 are longitudinal and transverse central sections thereof, and

Fig. 7 is a transverse section through one pair of the strip-clamping elements.

In the form of the invention shown in the drawings, the holder comprises a main block It and a pressure plate II. For accommodating a test strip A, x 3" in size, these parts may have dimensions of about by 1 by 3 and A" by 1 /2 by 3", respectively.

The main block In is provided with four symmetrically placed holes 12 (Fig. 7) through which the shanks of the headed strip clamping elements l3 are freely slidable. These four strip clamping elements are threadedly engaged in the pressure plate I l and secured in adjusted position therein by the lock nuts l4.

Threadedly engaged through the center of the pressure plate II is a jack screw IS the threaded stem of which is adjustable through the plate ll to abut the main block Ill and act as means to force apart said main block and pressure plate to draw the headed elements ['3 into strip clamping position.

In the forms shown, the jack screw member l5 has an opening therethrough and a headed member I6 passes through this opening and is threadedly engaged in the main block l0, so that retraction of the jack member I5 against the head of the member It acts as a means to draw together the main block and pressure plate and positively move the headed elements l3 into strip freeing position.

As is apparent from the drawings this assembly results in a simple and eflicient unitary structure. The several parts may be hardened for long life and may be made interchangeable and renewable. The working parts of the device, with the single exception of the clamping heads of elements l3, are all positioned rearward of the block it), and thus protected from the blastant during the blast peening of the peen strip. But a single operation is needed to securely clamp the peen strip in place, and to positively free it. The practical importance of this improvement may be appreciated when it is realized that by saving an average of only one minute in each mounting and removal of a strip as compared to the old form, fifteen man-minutes may be saved each hour, or two man-hours in an eight hour shift, so that the economic value of the new block is far above its added costs as compared to the conventional device heretofore employed.

While a preferred structure has been described to exemplify the invention, it is not limited thereto and its. scope is defined in the appended claims.

We. claim;

1. A quick acting. holder for peening gage strips, said holder comprising a main block having parallel passageways therethrough, a pressure plate therebehind, a plurality of headed strip clamping elements having shanks slidably extending through the passageways of said main block and fixedly carried by said pressure plate for bringing their heads into and out of clamping engagement with a strip positioned against the forward face of the main block, a jack screw threaded through the center of said pressure plate and bearing against the rear of said main block, said jack screw having a longitudinal passageway therethrough,, a rod extending through said longitudinal passageway and having one end fixedly connected to said main block and an abutrcent head formed on the other end behind the jack screw so that advancing of said jack screw against the back of said main block forces said bio-cl; and plate apart and draws said headed elements into strip clamping position, and retraction of said jack screw away from the main block and against the abutment head of said rod draws said 4 block and plate together and moves said headed elements into strip freeing position.

2. A peen-resisting holder for peening gage strips, said holder comprising a main block, a. pressure plate therebehind, a plurality of headed elongated strip clamping elements having shanks slidably passing through said main block and fixedly carried by said pressure plate, the heads of said elements being positioned in front of the forward face of the main block, said pressure plate having an orifice therethrough, an elongated headed member carried by said main block and having a shank extending rearwardly through said orifice with its head positioned therebehind, and bidirectional actuating structure carried by said elongated headed member between the main block and the head, said actuating structure cooperating with said plate for operation in one direction to extend through said orifice and force said main block away from said pressure plate and toward the heads of the clamping elements to clamp a gage strip under these heads, and operation in the other direction to force the head of said member away from said pressure plate and retract the main block from the heads of the clamping elements, the main block shielding the actuating structure from peening directed toward a gage strip clamped on the forward face of the main block.

ROBERT E. HUYET'I. FRANK NEWELL.

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

UNITED STATES PATENTS Number Name Date 57,447 Stockmar Aug. 21, 1866 458,276 Sherman Aug. 25, 1891 849,758 Titus Apr. 9, 1907 1,009,609 Wenneborg Nov. 21, 1911 1,412,170 Dixon Apr. 11, 1922 1,624,609 Maise Apr. 12, 1927 2,350,440 Almen June 6, 1944

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