US2537419A - Adjustable rear mount for machine guns - Google Patents

Description

J n 1951 P. E. PETERSON ADJUSTABLE REAR MOUNT FOR MACHINE GUNS Filed July 21, 1944 INVENTOR. Paul F Peterson A iiorzwy Patented Jan. 9, i951 V. UNITED STATES PATENT o rrics PauliF. PetersomLos Angeles, O'alifi, 'assignor to North American Aviation, Inc.

Application-Jilly 21, 1944-, Serial Ni"54 5,941

16' Claims.

The present invention relates to improvements in adjustable rear mountings for fixed machine gunsof a type particularly adaptable for aircraft installations.

It is an object of the present invention to provide amount suitable for the foregoing, purpose, which is generally compact in all dimensions and particularly in the vertical height whereby a minimum amount of clearance is required on an installation. In current gun placement designs in aircraft wherein a plurality of guns are included within the wing of a ship, difiiculties are frequently encountered owingto the very limited amount of clearance within the wing structure, especially in the outboard portion of the extremely thin wings employed on fighter ships. It accordingly becomes of considerable importance to provide a satisfactory mounting means including provision for adjustment ofthe gun in both azimuth and elevation and yet requiring aminimum amount of. clearance between the lower skin-of the wing andlthe bottom of the gun. It is a further object of this invention to pro-. vide adjustment means for a gun. mount as above described which are readily accessible and simple of operation. Previous designs have frequently required that adjustments be made from the underside of the wing. Such an arrangement has numerous disadvantages; such :as. generally re-- quiring two persons in order to perform the operation satisfactorily, one ion the wing to direct the operation, while a second operates the adjusting means beneath the wing. Such an arrangement also "generally resulted in aportion of the adjusting means projecting through the lower wing surface andinto the airstream, or a suitable access door was. required. The present arrangeme-nt is completely housed, accessible from above, can-be readily adjusted by one man, requires,v no special tools and is. completely selflocking immediately uponcompletion. of the required adjustment.

It is a furtherobject of: the invention to provide a rear gun mount which will improve the performance and accuracy of the gun during firing. To this end, the longitudinal recoil forces are not transmitted to the rearmount since the rear clamp is free-floating and self-aligning. The longitudinal recoil forces are entirely "taken by the front mount and the rear mount serves only to position the gun, i. e., takes loads only in the vertical or transverse horizontal plane. A considerable improvement in the dispersion pattern of the gun duringfiring is thereby effected.

Astill further object of the present invention is the provision of an adjustable rear gun mount including a quickly releasable securing means which maybe attached to the gun at any convenient point along the lower-side of the rear portion of the gun. ;This -mount may also be readilyinstalled-in such a-manner as to-support 2 the gun from above and may be attached to the upper. side of the rear portion of, the gun with equal facility.

Still further objects of the present invention are the provision of anadjustable rear-gun mount of simple design and rugged construction which lends itself readily to production, being inexpensive to build and having relatively few parts, providing a full range of adjustments which may be'quickly and easily madeand are automati cally secured by self-locking provisions.

Like reference characters designate similar parts in the several views of the drawings, in which:

Fig. 1 is-a top plan view of the rear mount;

Fig. 2 is an end elevation of the mount showing the gun in position;

Fig. 3 is a side elevation of the mount taken on line 3-3 of Fig. 1, indicating the gun in phantom;

Fig. 4 is a frag-mentarysection takenon 1' 4-4 -of Fig. 2; and

:Fig; 5 is a side elevation of a machine :gun mounted in accordance with the invention.

As an example of. one-formin which the in-- vention may beembodied, I have shown in thedrawing a-machine gun, indicated generally at A, mounted on a supporting-structure 4 (suchias a frame member "of a military airplane). The gun Ads of :a type (such as 'disclosecl in thepatent to; Browning No. 1,628,226) including a barrel Tb and a casing c, with-conventional recoil absorbing mechanism interposed between the barrel 'b and the casing c. The casing c is mounted on the support '4 by means'of a front mount d,v which 'formsa relatively rigid, recoil transmitting pivotal' connection between the'casing 'c and the :support l, and a rear mount 6 which provides whati maybe termed a longitudinally floating-connec-. tion between the'casing' c and the support '4 so as toofi'er no resistance to the recoil, .but which is adapted "to "restrain the rear end of the gun against movements transverse to the longitudinal axis of the gun, either in a vertical or a horizontal direction.

The rear mounting unit e, which includesfur- 4 ther detailed features of the invention, comprises a bracket 1 having parallel side flanges 2-3 whereby the mount is attached to'the, supporting structure 4 as by bolts 5-5, 6-45. An adjustable member 1 whih comprises a pair of 'rearwardly to right'or-left by the-rotationpof'shaft ll. Gun,

3 engaging means are supported upon the block. A hexagonal head I4 is provided at one end of the shaft ll whereby the required rotation may be readily accomplished in order to secure the desired adjustment of the gun IS in azimuth. A spring detent I6 is arranged to bear against the flat surfaces of the hexagonal head l4, thereby providing for the retention of the adjustment. The application of a turning force of sufficient moment to rotate the shaft may be readily obtained with a suitable tool, the locking spring deflecting momentarily to permit the passage of the corners of the head l4.

The arm 9, extending forwardly and upwardly, is slotted at I! to receive a bearing block I8 which is journalled in the bifurcated end portion of the arm, and cooperatively engages an adjusting screw I9. The lower extremity of this screw is journalled in a slotted plug inserted within a boss 2| which is slotted at 22 to permit the selfalignment of the assembly throughout the full range of adjustment. Rotation of the adjusting screw l9 in engagement with the bearing block l8 will secure the vertical adjustment of the gun by virtue of the entire adjustable unit 189 being pivoted about the pin l0. A spring detent 23 secured to the frame at 24 bears against a hexagonal portion 25 adjacent the lower extremity of the adjusting screw l9 whereby the desired adjustment will be retained.

The block [3, which carries the gun engaging means, is provided with an upwardly extending lug 26 received within a recess in the yoke 21 and is pivotally connected thereto by a short pin 28. The pin is secured to the lug 26 at 29. The lug 26 is positioned in spaced relationship to the sides of the opening provided in the yoke 21 and a pair of resilient washers 30-30 are inserted therebetween. This provides a free-floating arrangement wherein the yoke 21 is relatively unrestrained and therefore may be permitted to move axially upon the pin 28, the resilient washers serving as buffers. This prevents longitudinal recoil forces of the gun from being transmitted to the mount and the supporting structure, thereby preventing a restraining action from occurring at the rear mount whereby the dispersion pattern of the gun is considerably improved.

The floating arrangement provided between the block l3 and the yoke 21 by the pin 28 also allows the gun engaging clamp to become self-aligning by way of rotation of the yoke on the pin. This feature is advantageous in that minor misalignments which may be encountered between the various portions of the gun mount and supporting structure are readily accommodated.

The yoke 21 is provided with quickly releasable clamping means for engaging the gun and securing it to the mount. This means comprises a fixed jaw 3| and an opposing movable jaw 32 pivoted at 32a to the yoke 21, together with an adjusting screw 33, threaded through a boss 34 on the yoke 21, bearing against the movable jaw 32, and having a wing head 35 for engagement by the fingers of an operator. Means for retaining the required clamping adjustment are also provided, comprising a resilient member 36 apertured at 31 to engage the hexagonal portion 38 of the head 35. The resilient member, secured to the yoke at 39, may be deflected toward the yoke to be disengaged from the hexagonal portion of the head 35 to allow the adjusting screw to be rotated and release the tensi-oning means for free rotation and when released will spring back into locking engagement with the hexagonal portion 38.

This quickly releasable clamp arrangement provides a means whereby the gun may be engaged at any convenient point along the length of the lower edge. Alternatively the entire mount may be installed in an inverted position whereupon the clamping means will engage the corresponding portion of the upper edge of the gun case as at 40. This permits. a greater degree of latitude in designing such installations as well as facilitating the actual servicing operation, requiring removal and replacement of the guns. Servicing operations are further simplified by the provision of a light torque spring 4| bearing against the movable jaw 32 and tending to urge it constantly against the tensioning screw 33 whereby the clamping means is held in open position to receive the gun. As a still further aid, a lug 42 is provided on the block l3 and a spring 43 is attached to the supporting structure as at 44 whereby the entire unit l321 is held erect and in proper gun engaging attitude, avoiding the possibility of difiiculties being encountered by virtue of the yoke falling over during the placing of the gun.

I find that by employing a recoil transmitting forward mount in combination with a longitudinally floating but transversely restraining rear mount, that the dispersion firing pattern of the gun is very definitely improved. Where an attempt is made to restrain recoil through the rear mount as well as the front mount, the recoil induced dispersion effects upon the gun are more pronounced and the dispersion pattern becomes more irregular.

It may be noted that the upper portions of the lever 9 and adjusting screw l9 project upwardly beyond the bottom of the gun casing I5, in a plane at one side of thegun casing, while the bracket I, the bearing portion of the lever 9, and the clamp 21 are largely disposed between the lower side of the gun and the support 4. The head of the screw l9 projects upwardly at one side of the gun so as to provide for easy access for adjusting purposes.

I claim as my invention:

1. An adjustable gun mount comprisingabracket for attachment to a support, a clamp adapted to embrace and engage the lower portion of a gun casing, said clamp including a pair of spaced portions having aligned bearing apertures, a pin extended through said apertures and supporting said clamp for sliding movement in the direction parallel to the longitudinal axis of the gun, a lever having at one end an upwardly extending lug received between said spaced clamp portions and attached to and supporting the intermediate portion of said pin, cushioning means interposed between said lug and the respective spaced portions of said clamps, for yieldingly opposing said sliding movement, means pivoting an intermediate portion of said lever upon said bracket on a horizontal axis transverse to said longitudinal axis for adjusting movement in a vertical plane, and an adjustin screw forming an adjustable connection between the other end of said lever and said bracket for effecting said adjustment in a vertical plane.

2. A gun mount as defined in claim 1, wherein said adjusting screw extends upwardly and rearwardly and has at its upper end a head for engagement by an adjusting tool.

3. A mount for floatingly attaching a portion of a gun to a support comprising a lever, means for adjustably connecting said lever to said support. means for holding said. lever in adjusted position, and means fixed to the gun and carried by said lever means for carrying said gun with.

5. A device as recited in claim 4 and further including buffer means interposed between said pin and yoke.

6. A mount'for floatingly attaching the rear portion of a gun to a support comprising interengaging means one of which is to be fixed to the support and the other of which is fixed to the gun and carried by the first named means with freedom for sliding movement in the direction of the longitudinal axis of the gun and rotative movement in a direction transverse thereto.

7. A device as recited in claim 6 and further including bufier means interposed between said interengaging means.

8. A mount for floatingly attaching aportion of a gun to a support comprising a pin to be fixed to the support and extending substantially longitudinally of the gun, a yoke fixed to the gun and mounted on the pin with freedom for rotative and sliding movement, and buffer means between the pin and yoke. I

9. A mount for floatingly attaching a portion of a gun to a support comprising a lever, means for adjustably connecting said lever to said support, means for holding said lever in adjusted position, and means fixed to the gun and carried by said lever means for carrying said gun with freedom for movement in the direction of its longitudinal axis and rotative movement in a direction transverse thereto, and buffer means between the lever means and the means fixed to the gun.

10. A mount for fioatingly attaching a portion of a gun to a support for use in a mounting arrangement wherein another portion of the gun is relatively unyieldingly attached to the support, comprising interconnected elements one of which is to be adjustably fixed to the support and the other of which is fixed to the gun and carried by the first named element with freedom for movement in the direction of the longitudinal axisof the gun, and buffer means between the interconnected elements.

11. A mount for floatingly attaching a portion of a gun to a support for use in a mounting arrangement wherein another portion of the gun is relatively unyieldingly attached to the support, comprising interconnected elements one of which is to be adjustably fixed to the support and the other of which is fixed to the gun and carried by the first named element with fr edom for move support and the other of which is fixed to the gun and carriedby the first named element with freedom for yielding movement in the direction of. the long tudinal axis of the gun and rotational movementin a direction generally transverse to thejlongitudinal axis of the gun, and means 01 restraining said other element against movement in vertical and transverse horizontal directions.

13. A mount for floatingly attaching :a portion of a gun to a support comprising vertical adjustable means carried by the support, laterally adjustable means carried by said vertical adjustable means, and yoke means attached to said gun and to said laterally adjustable means with freedom for rotative and horizontal longitudinal movements but restrained against lateral movements in horizontal and vertical directions.

14. An adjustable gun mount comprising a bracket for attachment to a support, said bracket being interposed beneath the underside of the gun and said support, means for attachment to said gun, a lever on which said means is pivotally mounted, said lever being fulcrumed on said bracket for movement such as to effect adjustment of said gun, and an adjusting screw acting between said lever and said bracket and adapted to effect said adjusting movement of said lever, said adjusting screw and the upper portion of said lever being disposed at one side of the gun with the head of the screw projecting upwardly.

15. In a mounting arrangement for attaching a gun to a support, relativelyunyielding means for attaching one portion of the gun to the support; and means for fioatingly attaching another portion of the gun to the support comprising interengaging means, one of which is to be fixed to the support and the other of which is fixed to the gun and carried by the first named means for freedom of sliding movement in the direction of the longitudinal axis of the gun and rotative movement in a direction transverse thereto.

16. A mount for adjustably attaching a gun to a support comprising bracket means for attachment to said support, a lever fulcrumed on said bracket means for movement with respect thereto, means for holding said lever in adjusted position, gun engaging means carried by said lever and adjustable in a, direction generally at right angles to the direction of movement of said lever,

and means fixed to said gun and carried by said lever for carrying said gun with freedom for movement in the direction of its longitudinal axis and rotative movement in a direction transverse thereto.

PAUL F. PETERSON.

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

UNITED STATES PATENTS Number Name Date 1,594,365 Houbroe Aug. 3, 1926 1,628,226 Browning May 10, 1927 2,076,256 Swalm et al. 1 Apr. 6, 1937 2,293,069 McNeil et al Aug. 18, 1942 2,326,904 Trimbach Aug. 17, 1943 2,334,984 Berlin et a1 Nov. 23, 1943 2,335,835 Zietlow Nov. 30,- 1943 2,364,509 Bertran et a1 Dec. 5, 1944 2,380,773 McMullen July 31, 1945 2,385,218 Martin Sept. 18, 1945 FOREIGN PATENTS Number Country 7 Date 25,119 Austria July 25, 1906 324.308 Germany Aug. 26, 1920 483,847 Great Britain Apr. 12, 1938 491,353 Great Britain Aug. 31, 1938 865,951

France Mar. 24, 1941

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