US2490922A - Firearm - Google Patents

Description

Dec. 13, 1949 Filed Aug: 2'7, 1947 P. B. RUTHERFORD ETAL FIREARM a Shets-Sheet 1 mm m INVENTOR S Aim-R's. fil/fflfifofio KENNETH J. LOWE 0565A s50 BY 5) JANE A. LOWE 40mm.

ATTORNE -Dec. 13, 1949 I P. B. RUTHERFORD ETAL FIREARM 3 Sheets-Sheet 2 Filed Aug. 27, 1947 INVENTORS PETE/7 a. RUTHE/F F0190 Dec. 13, 1949 P. B. RUTHERFORD ETAL 2,490,922

FIREARM Filed Aug. 27, 1947 3 Sheets-Sheet 5 lNVENTbRS 1 675:? 5. RUTHEAFORD KEN/V5776 LAO/Vi 05654850 BY BY JANE-A. LOWE AOMRX.

Patented Dec. 13, 1949 'UNITED if s seam OFFICE 2.490.922 FIREARM Application August 27, 1947, Serial No. 770,774

11 Claims.

This invention relates to a safety mechanism for a firearm and more particularly to such a mechanism designed to lock the trigger against movement to a firing position.

It 'is'a principal object of this invention to :present a safety mechanism which is well adapted to low cost quantity production and one which, although achieving its low cost objective, has done so without sacrificing positiveness of action or other desirable functional qualities.

It is a further object of this invention to present a simple reliable safety which will positively prevent firing of the rifle from an unlocked bolt.

It is an object of a modified form of the invention to present a safety mechanism fulfilling the objects previously mentioned and which is, in addition, capable of being automatically set to Safe condition whenever the firearm is cocked.

It is contemplated that these objectives may best be attained by rotatably mounting on the rear end of the belt a trigger block carrying memher which can be located in various rotationally separated positions allowing for predetermined degrees of trigger movement.

The exact nature of the invention, as well as other objects and advantages thereof, will appear from consideration of the following specification referring to the attached drawings in which:

Figure l is a side .elevational view, partly in section, showing the working elements of the firearm.

Figure 2 is a longitudinal sectional view of the same mechanism included in Figure 1.

Figure 3 is a partial rear elevational view, the bolt being closed and the mechanism in Safe position.

Figure 4 is a partial cross-sectional view on the line 4-4 of Figure 2, the bolt being closed as in Figure .3 but the mechanism being .set in Firing position.

Figure 5 is a partial cross-sectional view, corresponding to Figure 4, with the exception that the bolt is shown in an unlocked position and the safety in Safe position.

Figure 6 is a partial crosssectional view corresponding to Figure 4, with the exception that the bolt is shown in an unlocked position and the safety in Firing position.

Figure 7 is .a side elevational view of the bolt body showing the detent opening therein.

Figure 8 is a rear elevational view, similar to Figure 3, showing a modified mechanism designed to automatically apply the safety when the bolt is unlocked. In this view the bolt is closed and the safety is -inFiring position.

2 Figure 9 is a partial cross-sectional view, corresponding to Figure 8, with the bolt in unlocked position and the safety shifted to Safe position.

Figure 10 is a partial cross-sectional view, similar to Figure 9, the bolt having been returned to closed position, carrying with it the safety in Safe position.

Figure 11 is a partial side elevational view of the modified mechanism.

Referring to the drawings by characters-o1 reference, there is shown a firearm comprising a stock I and a tubular receiver 3 mounting a barrel in usual fashion at its front end and suitably assembled to a stock. A breech bolt 4 of the upturn and pullback type is provided with a handle 5 and a locking lug 6 cooperatin with the usual locking recess and guide track in the receiver. At its chamber closing end, the breech bolt is provided with a conventional extractor and corn vention al spring loaded ejector plunger, it being noted that because .of the one-piece nature of the bolt, a clearance out is provided in the rear face of the barrel adjacent the chamber opening to permit the extractor to be rotated with the bolt relative to the barrel.

The bolt 4 is longitudinally bored to accept a striker 'l and has a slightly ofiset reduced bore to accept the firing pin 8 integrally secured to the striker. The striker is provided with an undercut flange 9 to act as a sear-engaging surface. A clearance slot is provided in the bolt to accept the sear nose ID of the trigger. In view of the fact that the whole bolt bod rotates relative to thereceiver, the rear portion of the clearance slot must be, carried around the circumference of the bolt through the same angle as the upturn of the bolt. jacent the sear nose when the bolt has been rortated to unlocked position, a slot may be carried forward to accept the sear nose during the pullback movement of the bolt. The forward terminal end of this slot is adapted to be enga ed by the forwardly facing/surface ll of the sear nose, which also acts as a bolt stop. In the usual fashion, the pulling of the trigger to an extreme rearward position when the .bolt has been pulled to the rear disengages the sear nose from the slot and permits the bolt to be withdrawn.

The trigger i2 is pivotally supported on a crosspin l3 in the receiver and a rearwardly extending arm thereon bears against a spring 14 which, at its other end, bears against a detent plunger l5. It is the function of the plunger to engage a notch l6 formed in the bolt body to prevent inadvertent opening of the bolt. This From the edge of this clearance slot ad- 3 detent also exerts enough frictional resistance to pulling back the bolt, when the trigger is pulled to clear the bolt stop, that there is little possibility of the bolt inadvertently falling clear and possibly picking up dirt or other foreign ma terial.

Within the bolt body a main spring I! bears at its forward end on the striker and at its rearward end on the inner surface of the safety E8. The safety is a caplike member suitably knurled to provide a secure gripping surface and received on the reduced rear portion of the bolt body. As seen in Figure '7, the bolt body is provided with W a detent slot 1 5 providing two semi-circular forclockwise rotation of the safety which can be facilitated by a slight forward pressure. For a right-handed shooter, the usual method of operation will be to grasp the safety between the right thumb and forefinger and the movement to Firing position will land the thumb in the of the engagement of the main spring against the inner face of the safety the screw will bear 7 against the rear face of the slot. In this way, the mainspring is retained and provides the spring force holding the safety detent into one or the other of the notches 2D or H.

Formed on the safety body is a segmental flange adapted to engage and limit the movement of'a rearwardly extending arm 23 on the trigger. The segment 24 has a great enough radial di mension that it prevents the movement of the trigger to striker releasing position when the safety is set to Safe position (Figure 3). Circumferentiaily, the segment 2e extends far enough to so oppose the trigger arm during the entire turning movement. of the bolt, in which the safety participates by reason of its engagement in the detent notch in the bolt body. See Figure 5 for the relative position of safety and trigger with the bolt unlocked.

When the safety has been rotated on the bolt body to its other or Firing position and the bolt is closed as in Figure 4, the segment 25 opposes the trigger arm 23. The maximum radial height of the segment 25 is such as to just permit the sear to disengage from the striker and the minimum radial height is that which will permit an undesirable amount of over-travel or slap in the trigger. For best performance, this height should be as near the maximum as the probable accumulation of production tolerances will permit.

With the s'afety set in Firing position, it will be apparent that rotation of the bolt toward an unlocked position will carry with it the safety and the segment 26 to oppose the trigger arm 23. This segment is of the same radial height as the segment 24 and consequently blocks striker releasing movement of the trigger. Figure 6 shows the relationship of the parts with the bolt rotated to completely unlocked position and the safety in Firing position.

It is desirable to adjust any trigger mechanism for a short clean releasing movement, but such an adjustment offers a possible hazard of off if the bolt is carelessly handled or slammed shut. Regardless of the position of the safety, the construction presented here is of great assistance in overcoming this danger for the trigger is positively blocked from jarrin out of engagement until substantially the entire locking surface of the receiver recess is opposed to the bolt locking lug.

To make the condition of the safety instantly apparent to the user, a white enamel or lacquerfilled notch 2'1 on the safety is correlated with a green-filled notch 28 on the bolt, indicating EtI" appropriate position to grasp the stock without fumbling or lost motion. If an opportunity for a shot is lost and it is desired to switch back to Safe position, the thumb will ordinarily be in position to be immediately closed upon the safety.

The modified safety mechanism shown in Figs. 8 to 10 is particularly desirable for a single shot rifle, since it causes the safety to be automatically applied whenever the bolt is rotated to unlocked position. The result is that each time the rifle is loaded, the safety will be applied without requirin any conscious action on the part of the user, and the rifle cannot be fired without consciously releasing the safety. Since single shot rifles are often purchased for boys, who by reputation may tend to be careless of details, the value of this type of safety will be obvious.

Referring to the drawings, it will be seen that the modified mechanism is of generally similar construction to that previously illustrated herein. Reference numerals between I00 and I29 have been applied to parts which are the same or exact equivalents to those in the earlier modification. Reference numerals between 5% and H30 have been used to designate those parts different from those previously discussed.

As previously described, the safety H8 forms a closure for the rear end of the bolt I04 and is thrust rearwardly thereon by the main spring I IT. The thrust of the main spring is resisted by the detent screw I22 received in slot H9 in the bolt and releasably engaged with either notch I20 or I2I. A notch I2! on the safety correlates with notches I28 and 129 on the bolt body to afford an instantaneous indication of the condition of the rifle.

The principal change to the rifle in the modified form has been the provision of a pin 50 mounted in the rear end face of the receiver I03 which engages with the flange 5| on the safety when an attempt is made to open the bolt with the safety in Firing position and resists the normal tendency of the safety to turn with the bolt. The result is that when the bolt is rotated to unlocked position, the safety is shifted to Safe position on the bolt unless it alreadyoccupies that position. In"Safe position with the bolt looked, a segment 52 of the flange opposes the arm I23 on the trigger to block release of the sear nose H0 from the flange I89, as shown in Fig. 10.

In Firing position, with the bolt locked, shown in Fig. 8, a segment 53 of less radial height serves as a trigger stop to prevent undesirable overtravel of the trigger. A flange 54 is provided on the bolt in position to block the trigger before the bolt can be rotated to a degree which causes a dangerously reduced area of the area-e22 bolt lug 1 Elite "be opposed by thewall of the bolt lockingrecess. As previously pointed out,,the rotation of the bolt to unlocked position shifts the safety to Safe position. When the bolt is rotated back to locked position, the safety is unopposed by the stop pin on the bolt and is therefore free to follow its natural inclination to rotate with the bolt by reason of the interengagement of the screw [22 in the appropriate detent notch in the 1 bolt. During the initial phase of the rotation to closed position, the trigger arm I23 is opposed by the segmental flange 54 on the bolt body. From a point in advance of that in which the bolt reaches a locked position, in which it is releasably retained by the detent H5, the segment 52 of the safety flange takes over the trigger blocking function to insure that at no time during the final closing movement of the bolt can the striker be jarred off from the sear.

The same push-in and turn movement is utilized to operate this safety as in the previous modification.

Although two more or less specific embodiments have been disclosed herein, it is not intended that the invention should be considered to be limited thereby. The invention is considered to extend to all equivalent constructions within the scope of the claims appended hereto.

We claim:

1. In a firearm including a receiver, an upturn and pullback bolt in said receiver having rotationally separated locked and unlocked positions, a striker within said bolt, a spring within said bolt in engage-ment with said striker to urge same forwardly in said bolt, and a trigger mounted in said receiver and provided with sear means engageable with the striker to releasably hold same in a cocked position against the urging of said spring; safety means comprising in combination an element extending from the trigger and provided with a blocking surface, a member rotatable on said ibolt between a Safe position and a Firing position thereon, detent means engageable between said member and said bolt to releasably retain the member in the selected one of said positions on the bolt, flange means on said member formed to define at least one segmental abutment which is opposed to said blocking surface when said member is set in Safe position and said bolt is in locked position, said abutment being of suflicient radial height to positively prevent movement of the trigger to striker releasing position and of sufficient circumferential extent that the abutment will continue to block the trigger as the bolt is rotated from locked position toward unlocked position.

2. Safety means as described in claim 1, said member having a second segmental abutment formed on said flange means and positioned in opposition to said blocking surface when the member is in Firing position to permit limited movement of said element for release of the striker but to prevent material overtravel thereof.

3. Safety means as described in claim 2, said member having a third segmental abutment formed on said flange means and positioned in movement :blocln'ng opposition to the blocking surface on said element when the bolt has been materially moved away from locked position and said member is in Firing position, said firstmentioned abutment being constructed and arranged to be in movement blocking opposition to the blocking surface on said element when said member is in Safe position when the bolt has been moved from locked position as well as when the bolt is in locked position.

4. Safety means as described in claim 1, said member engaging the rear end of the bolt to form a cap-like closure therefor.

5. Safety means as described in claim 4, the inner surface of said member being in abutting relation tothe rear end of the striker spring to serve as a stop therefor. v

6. Safety means as described in claim 5, said bolt being provided with a cross slot and said member being retained on said bolt against the action of the striker spring by a stop in the member extending into the slot.

7. Safety means as described in claim 6, forwardly facing circumferentially spaced detent notches being formed in the rear edge of said cross slot for selective engagement with said stop, said notches being circumferentially spaced in accordance with the separation between Safe and Firing positions.

8. In a firearm including a receiver, a bolt rotatable in said receiver to a locked position therein, a striker in said bolt, a trigger, and a sear controlled by said trigger and operable to releasably retain the striker in a cocked position; safety means comprising in combination a segmental flange integral with said bolt constructed and arranged to be rotated therewith into engagement with a portion of said trigger to prevent movement of the sear to striker releasing position whenever the bolt has been rotated materially away from its locked position in said receiver, a manual safety member rotatably mounted on the bolt and arranged to be selectively positioned in rotationally separated Safe and Firing positions, and an abutment on said manual safety member arranged with the bolt in locked position to be opposed to a portion of the trigger to prevent movement of the sear to striker releasing position when the member is in Safe position and clear of said trigger portion to permit movement thereof when the member is in Firing position.

9. Safety means for a firearm including in addition to those defined in claim 8 detent means engaged between the bolt and said member, releasably retaining the member in a pre-set position, and a stop surface on said receiver in opposition to the said abutment on said member, the abutment and said stop surface being constructed and arranged to engage each other and prevent said member from rotating with the bolt when the bolt is rotated to an unlocked position with said member in Firing position, whereby said member will be shifted automatically to Safe position as an incident to rotation of the bolt to unlocked position.

10. Safety means for a firearm including in addition to those defined in claim 9 a second abutment on said member positioned in opposition to a portion of the trigger when the member is in Firing position, said second abutment being constructed and arranged not to engage the said portion of said trigger before the trigger has moved to striker releasing position and serving as a trigger stop to prevent material overtravel thereof.

11. Safety means for a firearm as defined in claim 10, said member having the general form of 7 a cap secured on the rear end of said bolt to serve as a closure therefor.

PETER B. RUTHERFORD. JANE A. LOWE, 5 Administratria: of the Estate of Kenneth J. Lowe,

Deceased.

REFERENCES CITED The following references are of record in the 10 file of this patent:

Number 8. UNITED STATES PATENTS Name Date Nelson Sept. 7, 1915 Page Apr. 2, 1929 Loomis Aug. 29, 1933 Mossberg Feb. 11, 1936 Rice Apr. 24, 1945

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