US2404118A - Method of making triggers - Google Patents

Description

y 16 i946. 'v. G. YAWMAN- 2,404,118

METHOD OF MAKING TRIGGERS Filed May 10, 1945 INVENTOR. n 4 I/ofar 6I I/za/man i Patented July 16, 1946 UNITED STATES PATENT OFFICEv METHOD oF MAKING TRIGGERS Victor G. Yawman, Rochester, N. Y., assign'or to Yawman Metal Products, Inc., Rochester, N. Y., a corporation of New York Application May 10, 1943, Serial No. 486,442

6 Claims.

This invention relates to a method of making triggers.

In the past, it has been the practice to make a trigger for a Colt automatic pistol by subjecting a single block of metal to a series of expensive and exacting machining operations to insure rigidity and accuracy of the nished product. While it has been proposed to make such triggers by welding certain parts thereof together, such welded construction has not been acceptable owing to the fact that certain of the parts, made of thin stock, had to be welded to parts made of necessarily thicker stock, with resulting unsatisfactory joints. Furthermore, the welding operation produced irregular surfaces which had to be ground smooth in order to produce a satisfactory finish.

In accordance with one feature of the present invention, there is provided a trigger having a saddle-shape linger-engaging portion with a channel at its rear to receive a loop-like extens1on.

In accordance with another feature of this invention there is provided a novel method according to which a trigger is made from sheet metalv parts by a series of blanking and forming operations followed by the assembly and staking of the parts together to produce a. trigger unit having all the strength and accuracy of a trigger machined from a single block of metal.

In the drawing:

Figs. 1 to 6 inclusive show the successive steps of making the linger engaging portion of a trigger from a blank of material, Fig. 5 being a section taken on the line 5-5 of Fig. 4;

Figs. 7, 8 and 9 show successive steps in the blanking and forming of the trigger extension;

Figs. 10 and 11 are respectively a side view and a top view showing the shape of the trigger extension after the final forming operation;

Fig. 12 shows the linger engaging portion and the trigger extension assembled together ready for the staking operation;

Fig. 13 is a side elevation of the nished trigger after the staking operation; and

Fig. 14 is a sectional view taken on the line I4-I4 of Fig. 13, particularly showing how the staking serves to hold the parts of the trigger in assembled relation.

The trigger of the present invention comprises a saddle-shaped, finger-engaging portion I, with a knurled front 2, with a rear channel 3 extending from the top to the bottom thereof. This channel has mounted therein the pairs of opposltely extending lugs 4 on the registering ends of the loop-like trigger extension 5" (Figs. 11 and 13). While the parts may be secured together in any suitable manner, it is preferred to upset" parts 6 of the nger portion to engage the rear sides of the lugs 4 with their front sides in contact with the rear surface of the finger portion as shown in Figs. 13 and 14.

According to the iirst step of the present method of making this novel trigger, the finger engaging portion I thereof is stamped from sheet metal to have the outline indicated in Fig. '1.-

In the next stop, shown in Fig. 2, one surface of the blank I is formed with a knurled strip 2 extending longitudinally along a'rnedialv poring this step, the now arcuate blank is bent into saddle-shaped or U-shaped form about its'longitudinal depression, in fact, thisl depression'iinsure's proper bending of the blank and thedesired -low of metal during this forming operation. It will be noted that as a Vresult of this.

forming operation, the blank now is provided at each end thereof, with a pair of ears 9, resulting; from the excess material found desirable in holding the arcuate blank during this last-mentioned v forming operation. However, in the finished trigger, these ears are unnecessary and consequently the saddle-shaped blank is subjected to a broaching operation which removes them and provides both ends of the formed blank with straight, parallel surfaces I0. The blank thus formed may be subjected to the usual finishing operations to remove burrs and the like.

The extension of the trigger 5 is stamped from sheet metal to provide a blank, comprising a band terminating at each of its ends in a pair of oppositely extending lugs 4, as illustrated in Fig. 7. The extension blank is next formed into the Shape illustrated in Figs. 8 and 9 wherein the lug portions 4 thereof are bent into parallel olf-set relation with respect to the main part of the blank, being connected thereto through curved portions II. In the next forming operation, the blank thus far formed is bent sharply on the diagonal lines I2 to provide the loop-like portion with the two pairs of' lugs 4 positioned side by side, as shown in Figs. 10 and 11.

In assembling the two parts of the trigger unit together, the pairs of lugs 4 of the extension are forced into the channel space 3 in the 3 finger-engaging portion, in the position shown in Fig. l2. When thus assembled, the parts are staked together in a suitable press by having portions 6 of the finger portion upset behind the mentioned lugs. Any excess metal may be trimmed away and the parts may be suitably finished in accordance with the Well-known practice.

From the foregoing, it will be seen that this invention provides a novel trigger construction and a novel method of manufacturing the same wherein a minimum amount of metal stock is required and wherein a novel series of inexpensive blankng and forming operations suice. This novel method thereby obviates the need of inachining operations by skilled operators and greatly reduces the time required as Well as the cost of producing triggers.

What I claim is:

1. The method of making a trigger which comprises punching an elongated nger hold blank from sheet metal, forming said blank into a saddle shape to provide a rearwardly opening channel, stamping a trigger extension blank from sheet metal, forming said extension blank into a loop with its ends in registering relation, and staking the registering ends of said loop in said channel with the principal plane of the loop extending at right angles to the principal axis of said nger hold blank.

2. The method of making a trigger which comprises punching a nger hold blank having a long and a short axis, bending the blank into arcuate form about its short axis, bending the arcuate blank about its long axis .to provide a rearwardly opening channel, stamping a trigger extension blank from sheet metal, forming said extension blank into a loop with its ends in registry, and finally securing the registering ends of said loop in said channel with said loop at substantially` right angles to the long axis of said finger hold blank.

3. lThe method of making a, trigger which comprises punching a nger hold blank having a main axis and a short axis, knurling a medial strip on one surface of said blank along the main axis thereof, bending the blank into arcuate shape around its short axis, bending the arcuate blank` about its long axis into U-shaped form with said knurled strip exposed, stamping a trigger extension blank from sheet metal, forming said extension blank into a loop with each of its ends provided with a pair of oppositely directed lugs, said pairs of lugs being positioned in registry, and finally securing said lugs in the channel opening of Said finger hold blank.

4. The method of making a trigger which comprises punching a, nger hold blank having a main axis and a short axis, knurling a medial strip on one surface of said blank along the inain axis thereof, forming a long narrow depression in the other surface of said blank along the main axis thereof, bending the blank into arcuate shape around its short axis, bending the arcuate blank about said depression into U-shaped form with said knurled strip exposed, stamping a trigger extension blank from sheet metal, forming said extension blank into a loop With each of its ends provided with a pair of oppositely directed lugs, said parts of lugs being positioned in registry, and finally staking said lugs in the channel opening of said finger hold blank.

5. The method of making a trigger which comprises punching an elongated nger hold blank from sheet metal, folding said blank lengthwise to provide a longitudinal channel, stamping a trigger extension blank from sheet metal, forming said extension blank into a loop with its ends in registering relation, and staking parts of said folded finger hold blank about portions of the registering ends of the loop to hold said loop in said channel with the principal axis of the loop extending at right angles to the principal axis of said finger hold member.

6. The method of making a trigger which comprises punching from sheet metal, an elongated finger hold blank with excess end portions, folding said blank lengthwise -to provide a longitudi-` nal channel, removing said end portions to provide substantially parallel end surfaces on said finger hold, stamping a trigger extension blank from sheet metal, forming said extension blank into a loop with its ends in registering relation, and staking parts of said folded nger hold blank about portions of the registering ends of the loop to hold said loop in said channel with the principal plane of the loop extending at right angles to the principal axis of said finger hold.

VICTOR G. YAWMAN.

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