US3619926A - Bolt actuated ejection port cover - Google Patents

Abstract

METHOD AND APPARATUS FOR COVERING AN EJECTION PORT IN THE RECEIVE OF A FIREARM. THE COVER IS BOLT-ACTUATED, AND TELESCOPICALLY MOVES IN CONCERT WITH THE BOLT AS IT IS RETRACTED FROM THE CLOSED BREECH (BATTERY) POSITION TOWARDS THE OPEN BREECH POSITION. A POINT IS REACHED IN THE TRAVEL OF THE COVER, WHEN ITS TRAVEL IS RESTRICTED BY AN ABUTMENT IN THE INTERIOR WALL OF THE RECEIVER, WHEREUPON THE COVER IS CAUSED TO ROTATE WITH THE FURTHER WITHDRAWAL OF THE BOLT, SUBSTANTIALLY UNCOVERING THE ENTIRE EJECTION PORT AREA.

Description

J. M. ALDAY Nov. 16, 1971 3 Shoots-Shoot 1 Filed April 6, 1970 .r O t m V h I James M. Alday Nov. 16, 1971 I J. M. ALDAY 3,619,926

BOLT ACTUAIED EJECTION PORT COVER Filed April 6, 1970 3 Sheets-Sheet r:

Inventor: James M. Aldag Attorneys NOV. 16, 1971 J, ALDAY BOLT AGTUATED EJECTION PORT COVER 3 Sheets-Sheet 5 Filed April 6, 1970 Inventor James M. Aldag Atto rney United States Patent 3,619,926 BOLT ACTUATED EJECTION PORT COVER James M. Alday, Williamson, N.Y., assignor to Remington Arms Company, Inc., Bridgeport, Conn. Filed Apr. 6, 1970, Ser. No. 25,815 Int. Cl. F41c 11/00, 27/08 US. C]. 4216 R 7 Claims ABSTRACT OF THE DISCLOSURE Method and apparatus for covering an ejection port in the receiver of a firearm. The cover is bolt-actuated, and telescopically moves in concert with the bolt as it is retracted from the closed breech (battery) position towards the open breech position. A point is reached in the travel of the cover, when its travel is restricted by an abutment in the interior wall of the receiver, whereupon the cover is caused to rotate with the further withdrawal of the bolt, substantially uncovering the entire ejection port area.

The invention relates to receiver mechanisms and more particularly to a method and apparatus for covering an ejection port in the receiver of a firearm.

The prior art generally discloses two types of covering mechanisms:

(a) those lids which are hinged to the receiver and hip open to expose the ejection port, and

(b) those covers which telescopically slide within the receiver as the 'bolt is retracted towards the open breech position.

The first-mentioned variety of coverings may be seen by reference to the patents of:

Sampson et al., US. Pat. No. 2,428,683, issued Oct. 7,

Reed, U.S. Pat. No. 2,940,201, issued June 14, 1960; and

ivy, US. Pat. No. 3,030,722, issued Apr. 24, 1962.

The second-mentioned type of coverings are to be seen with reference to the patents of:

Gans, US. Pat. No. 2,341,767, issued Feb. 15, 1944; and Browning, US. Pat. No. 3,397,473, issued Aug. 20, 1968.

The present invention is a radical departure from the above methods of covering the ejection port.

The present system contemplates rotating the port cover to expose the ejection window. This rotation can take place either as the sole means of exposing the port or may be used in conjunction with the telescoping method. In the latter case, a portion of the window is first uncovered by sliding the lid away a limited distance, and then the remainder of the window area is exposed by rotating the cover plate away from the port.

A purely rotative method requires that the ejection port present a narrower window, since the degree of rotation within the receiver is usually limited. A larger exposure in the port area necessarily requires a greater amount of lid travel, and hence cannot usually be accomplished by rotation alone.

When the telescoping method is combined with the rotative technique, the cover travels only a limited distance of the entire port length. There is no need to have a lengthy receiver to provide clearance for the cover in the open breech position.

As is usually the case in systems using a pure telescoping means, the receiver must be extended to the rear :1 distance equal to that needed for the cover to clear the port. The extension of the receiver length to accommodate the cover produces a rifle having an unsightly hump-backed appearance.

The present technique allows for a smooth sloping curvature for the rearward portion of the receiver, which not only presents a pleasing streamlined appearance, but provides for a better balance in the handling characteristics of the firearm.

The use of the rotation technique alone requires no telescopic movement, and thus, also provides for the aforementioned improvement in the rearward portion of the receiver.

The hinged-type covers, while providing for a shorter receiver of pleasing appearance, are themselves unsightly in their operation.

When the lid flips open, the lid poses an obstruction to the eye, which may interfere with the proper sighting of the target. It may also interfere with the mounting of telescopic sights upon the gun.

Thus, it is evident that in addition to presenting a new method of covering the ejection port, this invention also presents many advantages which are not available with the other techniques.

:It is a primary object of this invention to provide a means of covering the ejection port in a receiver of a firearm wherein the cover plate need not extend into the rearward portion of the receiver a distance equal to the ejection port length.

It is another primary object of this invention to provide a means of covering an ejection port by rotation of the cover plate.

It is but another primary object of the invention to provide a receiver mechanism for the covering of an ejection port which will allow the rearward portion of the receiver to be designed with a smooth sloping curvature or otherwise present a pleasing streamlined appearance.

R is still another object of this invention to provide a cover plate mechanism for the covering of an ejection port which both telescopes and rotates within the receiver.

It is another object of this invention to provide an ejection port covering mechanism which is bolt-assemblyactuated.

These and other objects of the invention Will become apparent and will be better understood with reference to the subsequent detailed description and attached drawings, in which:

FIG. 1 is a perspective view of the receiver with the cover plate (port cover) covering the ejection port;

FIG. 2 is an exploded perspective view of the major parts of the receiver mechanism;

FIGS. 3 through 6 are sequential cut-away perspective views of the bolt and cover arrangement within the receiver wherein:

FIG. 3 shows the bolt and cover arrangement when the bolt is in the closed breech position, and the cover is fully covering the ejection port;

FIG. 4 depicts the bolt and cover arrangement when the cover has telescoped into contact with the abutment of the receiver, and before the bolt has been withdrawn far enough for the protuberance on the circumferential face of the bolt assembly to move in the slot of the cover plate;

FIG. 5 illustrates the bolt and cover arrangement when the cover has rotated away from the ejection port as the bolt has been further withdrawn to the point where the protuberance of the bolt assembly has moved in the dogleg portion of the cover plate slot;

FIG. 6 shows the bolt and cover arrangement with the bolt assembly in the open breech. position with its protuberance at the end of the elongated portion of the cover slot;

FIG. 7 is a front cut-away view of the receiver mechanism when the bolt is in the closed breech position as shown in FIG. 3;

FIG. 8 is a front cut-away view of the receiver mechanism when the bolt is in the open breech position as depicted in FIG. 6; and

FIG. 9 is a side cut-away view of the receiver mechanism when the bolt is in the open breech position as illustrated in FIG. 6, with the cover plate and spring element shown in section.

Generally speaking, the present invention is for a method and apparatus for providing the ejection port of a firearm receiver with a covering to protect the internal mechanism of the gun.

The method suggests having a rotating cover plate contiguous with the ejection port of the receiver and substantially covering the entire port area when the bolt is substantially in the battery position. The bolt is moved a limited distance from the battery (closed breech) position towards the open breech position. The cover plate is rotated to substantially expose the entire port area, as the bolt is withdrawn towards the open breech position.

The novelty of the ejection port mechanism resides in the means which, first, telescopically retracts the cover plate a limited distance within the receiver in substantial conformity with the retraction of the bolt from the closed breech position towards the open breech position for the purpose of exposing a portion of the port area, and then rotating the cover plate away from the port window to substantially expose the remainder of the port area, as the bolt is further retracted towards the open breech position.

Now referring to FIG. 1, a perspective view of the receiver is shown with the cover plate as it substantially covers the ejection port. The cover plate 9 is contiguous with the ejection port 8 of the receiver 7. The cover plate has a rounded cut-away portion 5, which is cut from the plate so as to clear the port window when the plate is rotated, as will be explained hereinafter. This open portion is covered by the bolt assembly 6 which lies directly behind the cover plate. This provides for complete coverage of the port area. The bolt is in the closed breech position, as is also illustrated in FIG. 3. FIG. 3, however, shows the bolt assembly and cover mechanism from the side of the receiver opposite the port window. Action bars 3 and 4, respectively, telescope the bolt assembly within the receiver. This is accomplished by way of projections 13 and 14, respectively, which engage the bolt assembly 6 through slots 23 and 24 (not shown) as depicted in FIG. 2. The action bars are guided within the receiver by means of slots 33 and 34, respectively, which run through the interior wall of the receiver.

The bolt assembly 6 has a bolt head 17 which has locking lugs 18 on the periphery thereof. The lugs marry with the lugs (not shown) positioned in nose piece 1. The nose piece 1 projects into recess 12, when anchor portion 2 of the barrel extension is fitted to the front of receiver 7. This is accomplished by means of bolt 26, which is fastened to receiver 7, and passes through hole 27 of the anchor portion.

Neglecting the receiver housing, the cover mechanism comprises the key parts of: cover plate 9, bolt assembly 6, and spring 40.

The spring 40 has a pin 21 which fits into hole 22 in the bolt assembly. The pin positively places the spring in relation to the bolt assembly. The spring also possesses a contoured portion 30 which conforms to the circumferential surface of bolt assembly 6 so as to aid in relating the parts to act together.

The spring is further provided with two leaf-type arms, and 16, respectively. The arm 15 conforms to slot of the bolt assembly to provide a flush fitting. When the bolt slides within the receiver, these arms alternately bias the cover plate in what can be described as a rocking motion of the spring 40 about bolt assembly 6 so that in the extreme rearward position of the bolt, the rear arm is pushed down by the sloping top interior of the receiver, placing a greater load on the front arm, holding the cover securely against the receiver.

The cover plate 9 fits over the spring and bolt assembly as shown in the various views. The cover plate is con toured for rotation within the receiver.

The arms 15 and 16 contact the underside (concave face) of the cover plate as the bolt is withdrawn from the closed breech position (FIG. 3) towards the open breech position (FIG. 6). At the extreme rear end of the bolt travel, the arm 16 of the spring contacts the interior wall of the receiver, as it rides off the inside surface of cover 9. The action of the spring serves several purposes:

(1) It forces the cover plate against the interior wall of the receiver so that it will have a snug fit. This will prevent the cover from rattling.

(2) It influences the plate to move in conformity with the bolt as it telescopes within the receiver; and

(3) It causes the cover plate to make positive engagement with travel limiting abutments within the receiver wall (this will be described more fully hereinafter with reference to FIGS. 3 through 6).

The cover plate has a slot 25 extending longitudinally therethrough. The slot is composed of two sections:

(a) a dog-leg bend at the fore-end of the plate; and

(b) a straight elongated slot portion extending therefrom.

The protuberance 19 of the bolt assembly fits into the slot for the purpose of camming the plate to rotate away from the ejection port as the bolt is withdrawn from the closed breech position at the point when the cover plate becomes restrained from sliding in concerted movement with the bolt (see FIGS. 4 and 5).

OPERATION OF THE MECHANISM Referring to FIG. 3, the bolt is shown in the closed breech (battery) position. The cover plate 9 is resting upon the bolt assembly, and is covering the ejection port window 8 as shown in FIG. 1. The bolt is withdrawn from the closed breech position towards the open breech position as depicted by arrow 41. As the bolt is withdrawn, the cover plate is forced to move with the bolt assembly due to the frictional drag effect of the spring (not shown), and from the drag effect of the camming protuberance on the bolt assembly.

The receiver 7 has an interior Wall 38. At the rear of the receiver Wall is an abutment 39. The cover plate moves in conformity with the bolt until its back end 37 makes contact with the abutment 39. At this point, the cover is restrained from further telescopic movement within the receiver. The protuberance 19 of the bolt assembly will now be forced to move in the slot of the cover plate 9. The slot is composed of a dog-leg portion 35 and a straight elongated portion 36 as shown. The protuberance 19 is originally resting at the aforemost part of the dog-leg portion of the slot as shown in FIG. 3.

FIG. 4 depicts the cover plate as it has just come up against the abutment. The protuberance 19 has just started to move in slot 35. The cover plate 9 which has telescoped away from a major portion of the port window 8 is now forced to rotate away from the window as shown by arrow 42.

As the bolt assembly is further retracted as in FIG. 5, the protuberance moves to the end of slot portion 35, thus completely rotating the cover plate away from the ejection window as depicted by arrow 43. At this point, the ejection port area is completely open, and the protuberance is positioned at the beginning of slot portion 36.

FIG. 6 illustrates the bolt and cover plate arrangement, when the bolt is in the open breech position. The protuberance 19 of the bolt assembly has been caused to slide within slot portion 36 to the end thereof. Slot portion 36 does not serve to rotate the cover plate 9, since this is a straight slot portion, and the movement of the protuberance therein does not cam the plate.

Slot portion 36 has the function of allowing the bolt to travel to its extreme open breech position, since without this slot, the bolt assembly would be restrained from further backward movement after the plate had rotated clear of the ejection window.

FIGS. 7 and 8 represent frontal cut-away views of the receiver mechanism in its extreme positions. FIG. 7 shows the mechanism as it would appear in the FIG. 3 position, and FIG. 8 depicts the mechanism as it appears in the FIG. 6 position.

FIG. 9 presents a side cut-away view of the receiver mechanism when the bolt is in the extreme open breech position as shown in FIG. 6.

The bolt assembly 6 is flush against the back of the receiver 7. The cover plate 9 is flush with the interior wall 38, and its back end 37 is abutting the abutment 39.

Since the cover plate 9 is not drawn all the way back to the extreme open breech position as is common in the prior art, the outer surface 32 of the receiver can have a curvature to give a pleasing appearance as shown.

The preceding sequence of steps (FIGS. 3 through 6) were illustrative of the opening of the ejection port window. To close the window, the sequence of steps are almost the reverse of those shown.

The difference being that the cover plate 9 will telescope forward in the rotated position until the front end of the plate abuts against the traverse wall of the front end of the receiver recess. At this point, the cover plate is restrained from any further telescoping movement within the receiver, and the bolts further forward movement forces the protuberance 19 back through the slot to cam the cover plate into rotating to the closed window position.

Man modifications and variations of the above mech' anism and method will become evident to those skilled in the art. For example, it was previously mentioned that the cover plate may be purely rotated without the need for telescoping movement, if the port window is very narrow. The cover plate would then require less rotation to clear the ejection port. This is so, because with a greater degree of required rotation, the cover plate would abut against the railings or action bar in the interior of the receiver and would be incapable of further rotation necessary to clear the port area.

To accomplish the above method, the cover plate would be a greater length extending to the present abutment 39 and would be restrained from moving telescopically within the receiver by means of said abutment. Retraction of the bolt would immediately start the protuberance to move within the dog-leg slot of the cover plate, thus rotating the cover free of the window. The further withdrawal of the bolt would be affected in similar manner as before except the straight slot portion 36 would now extend the greater length of the now lengthened cover plate.

Of course, the aforementioned mechanisms can be used with lever-actuated bolts as well as in pump action firearms. It is also possible to utilize the exact same mechanism in an autoloading arm, provided the cover is rotated to clear an operating handle afiixed to the bolt, before the handle is moved rearward sufficiently to contact the end of cut-out 5.

It may also be possible to position the cover plate on the external surface of the receiver if so desired.

Variations and modifications as are evident to the skilled practitioner are considered to be within the purview of the scope and spirit of this invention as represented by the appended claims.

What is claimed is:

1. In an ejection port covering mechanism for a firearm comprising: a hollow receiver having an ejection port; a bolt slidable within the hollow of the receiver from a closed breech position to an open breech position; and a cover plate for substantially covering said port when the bolt is substantially in the closed breech position,

and which uncovers the port when the bolt is retracted from the closed breech position towards the open breech position; the improvement comprising:

means for first telescopically retracting the cover plate a limited distance within the receiver in substantial conformity with the retraction of the bolt from the closed breech position towards the open breech position, so that a portion of the port area is uncovered thereby, and then rotating the cover plate away from said port to substantially uncover the remaining port area, as the bolt is further retracted towards the open breech position.

2. A receiver mechanism of a firearm for substantially covering an ejection port of said receiver comprising:

a receiver having an ejection port and an interior wall defining a cavity for housing the mechanism;

a bolt assembly slidably disposed in said receiver, and

having a protuberance projecting from a circumferential surface thereof;

means for moving the bolt from a closed breech position to an open breech position;

an elongated telescoping cover plate slidably disposed within the cavity of the receiver for moving a limited distance in the receiver, the cover being contiguous to the ejection port when the bolt is substantially in the closed breech position; said cover having a camming slot for engagement with the protuberance of said bolt, wherein the cover plate is forced to rotate as the protuberance moves within the slot;

an abutment disposed within the interior wall of the receiver and engageable with said cover plate to restrict its telescoping movement within the receiver;

biasing means for biasing the cover plate to move in substantial conformity with the bolt as the bolt is withdrawn from the closed breech position towards the open breech position, and until the cover plate engages said abutment, wherein the cover plate is prevented from sliding any further within the receiver and the protuberance of said bolt assembly is then forced to move within the camming slot of said cover plate, whereby the cover plate is caused to rotate clear of the ejection port as the bolt is further retracted towards the open breech position.

3. The receiver mechanism of claim 2, wherein the biasing means is a flat spring element, a portion of which is contoured and pinned to the circumferential surface of the bolt assembly so as to act in conformity therewith.

4. The receiver mechanism of claim 2, wherein the cover plate is curved in conformity with the curvature of the receiver wall so as to be capable of rotating therein.

5. The receiver mechanism of claim 2, wherein the slot is characterized by an irregular dog-leg bend in a front portion of the cover plate for the purpose of providing rotative motion to said plate when the protuberance is caused to move therein.

6. The receiver mechanism of claim 5, wherein the slot is further characterized by an elongated straight section following said dog-leg 'bend as a tail section thereof; whereby the bolt is free to slide rearwardly within the receiver after the cover plate has rotated.

7. The method of uncovering an ejection port of a firearm receiver comprising the steps of:

(a) providing a bolt substantially in the battery position within the receiver;

(b) providing a cover plate contiguous with said ejection port and substantially covering the entire port area when the bolt is substantially in the battery position;

(c) retracting the bolt a limited distance from the battery position towards an open breech position; and

(d) concurrently rotating the cover plate within the receiver so as to substantially expose the entire port References Cited UNITED STATES PATENTS 8/1909 Ashton 4216 4/1922 Feederle 4216 8 1,878,038 9/1932 Von Frommer 42-l6 2,288,202 6/ 1942 Mossberg 42-16 2,940,201 6/1960 Reed 42-16 BENJAMIN A. BORCHELT, Primary Examiner C. T. JORDAN, Assistant Examiner

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