US3001312A - Firearm butt plate with liquid recoil absorbing device - Google Patents

Description

Sept. 26, 1961 c. s. CAMPBELL 3,001,312

FIREARM BUTT PLATE WITH LIQUID RECOIL ABSORBING DEVICE Filed March 24, 1958 2 Sheets-Sheet 1 INVENT OR. CLARK S. CAMPBELL P 1961 c. s. CAMPBELL 3,001,312

FIREARM BUTT PLATE WITH LIQUID RECOIL ABSORBING DEVICE I Filed March 24, 1958 2 Sheets-Sheet 2 INVENTOR. CLARK S.CAMPBELL BY 62,, TZZ$W United States Patent 3,001,312 FIREARM BUTT PLATE WITH LIQUID RECOIL ABSORBING DEVICE Clark S. Campbell, Ilion, N.Y., assignor to Remington Arms Company, Inc., Bridgeport, Conn., a corporation of Delaware Filed Mar. 24, 1958, Ser. No. 723,225 3 Claims. (Cl. 42-74) This invention relates to firearms and more particularly to a device for cushioning the forces of recoil at the time of firing so that the reaction of the firearm against the body of the operator is spread over a given period of time rather than allowed to act directly and more or less instantaneously.

The trend to lighter weight firearms of increased power means that greater recoil energies and higher recoil velocities are developed. With heavier weapons or ones with less power recoil energy has been less and the lesser recoil velocities have tended to spread the application of the recoil forces to the shooters body over a longer period of time, avoiding the painful and harmful short duration forces of great magnitude which characterize the lighter and more powerful arms.

Devices have been tried in the past which were intended to cushion the shock of recoil. However, these have not been satisfactory in operation or practical to manufacture due to complexity of fabrication, difiiculty of assembly and disassembly, inefficiency and other defects.

It is an object of this invention to provide an improved and practical shock absorption mechanism capable of being produced economically, and efiicient in cushioning recoil forces of large magnitudes.

It is a further object of this invention to provide an proved hydraulic recoil absorbing device which does not require the usual parts manufactured to close tolerance, or expensive complex sealing arrangements.

It is a further object of this invention to provide an improved recoil absorbing device which will function uniformly and satisfactorily for varying points of application of the shooters shoulder to the butt of the gunstock without binding or jamming of the mechanism.

Other objects and advantages will be apparent from the following description of the invention taken in conjunction with the accompanying drawings wherein:

FIGURE 1 is a partial side view of a firearm stock embodying the features of my invention showing the general arrangement and appearance.

FIGURE 2 is an enlarged side view of the firearm stock of FIGURE 1 with the flexible cover removed to show the arrangement of the mechanism parts.

FIGURE 3 is a vertical transverse section of the device of FIGURE 2 taken at line 3-3.

FIGURE 4 is a vertical longitudinal section of the recoil absorbing mechanism to show more clearly the inner portions and components.

Generally, the forces of recoil are regulated by hydraulic liquid flow through a throttling orifice in cooperation with a unique mechanism for insuring that the major parts between which the relative movement takes place are always in proper alignment for uniform movement free of binding or jamming due to varying points of application of the shooters shoulder resistance against the butt.

Looking at FIGURE 2, the gun stock 2 of a firearm is provided with a section 6 of reduced transverse dimensions and a bore 4 positioned longitudinally therein. Secured to the rear end of stock 2 by screws or bolts 18 is a member 17 having a passageway therethrough in alignment with bore 4 of the stock. Member 17 is formed 3,001,312 Patented Sept. 26, 1961 with two rearwardly projecting lugs 41 and 42. Member 17 carries two transverse pivot shafts 11 and 12 therein. Pivotally mounted on shafts 11 and 12 are rocker levers 14 and '15 respectively which are interconnected by meshed gear tooth portions at 16. The interconnected portions at 16 normally rest in abutting relationship against the end surface of stock 2. Rocker levers 14 and 15 are connected to a buttplate member 1, which is made of plastic, metal, or other material, by pins 10 and 13 respectively. As can be seen from FIGURE 2, this secures buttplate 1 to the stock 2 in a manner which allows only limited axial movement therebetween.

Buttplate member 1 is provided with a hollowed out interior portion 39 and two forwardly projecting lug elements for limiting movement toward the stock 2 and in which are mounted the pins 10 and 13.

R-igidly secured in the bore 4 of the stock 2 is a tubular element 7 which extends through member 17 toward buttplate member 1 and, in conjunction with projections 41 and 42, supports crosshead element 19 against movement toward stock 2. Crosshead element 19 is positioned laterally by the hollow 39 in the buttplate 1 and is provided with a central metering or throttling orifice 20. A liquid container 23 of flexible material is provided, having a rearward portion set in the hollowed out interior portion 39 of the buttplate member 1 arranged to be compressed by crosshead element 19 during firing. The container has a necked down portion 21 extending through the metering or throttling orifice 20 in element 19 and an enlarged portion connected therewith positioned in the rearward end of tube 7. A spring biased plunger 9 slidably mounted in tube 7 exerts a force rearwardly on the container 23. The spring 8 is known as the oil return spring. The rearward inner wall of buttplate member 1 is provided with a throttling projection 22 which is aligned with the orifice 20 in the crosshead element 19.

Buttplate member 1 and stock 2 are urged apart to the extent of the limited axial movement therebetween by two spring-urged plungers 33 which together with their preload springs 31 are mounted in axial bores 32 in the stock 2.

The flexible container 23 is filled with a suitable hydraulic liquid F and, in the equilibrium or rest position as shown in FIGURE 2, contains the major portion of the liquid rearwardly of orifice 21. In my preferred embodiment, shown, the preload springs 31 each initially exert a force of about 17 pounds to prevent movement of the device from the pressure with which the shooter may pull the gun against his shoulder and to speed repositioning of the device after firing and oil return spring 8 exerts an initial force of about 3 pounds for satisfactory operation.

A flexible resilient sleeve 3 is fitted over the opening between the members 1 and 2 to provide a pleasing appearance and prevent foreign matter from entering the mechanism.

In operation, upon firing of the firearm with which the device is associated, the stock is forced toward the buttplate element 1. Recoil force is transmitted by tube 7 and projections 41 and 42 to crosshead 19, tending to compress the liquid F in container 23. The rocker levers 1 4 and 15 commence their pivoting motion as relative motion between members 1 and 2 commences. The liquid F is then forced forwardly through orifice 21 into the portion of container 23 lying in tube 7, loading spring 8. Springs 31 are also put under further compression. As crosshead element 19 moves rearwardly relative to buttplate element 1, the throttling projection 22 moves into orifice 21. The shape of the throttling projection is such as to reduce the effective area of the orifice 21 the desired amount at every instant so as to retard the relative movement of stock 2 with respect to buttplate 3 element 1 with the force desired for that instant. After the recoil forces have dissipated, the springs 8 and 31 return the parts to the initial position and cause the liquid F to return to its rest position between the buttplate element 1 and crosshead element 19.

The point of application of shoulder resistance to recoil forces varies with the individual shooter from place to place between points indicated at A and B. It will appear that if the shoulder resistance is applied at or near point A or B there is a tendency to cock or tilt buttplate element 1 with respect to the remainder of the structure. This would cause misaligment and jamming during the relative movement between parts 1 and 2 were it not for rocker levers 14 and 15 which provide a force equalizing linkage to maintain the parts in alignment for free movement.

Thus I have provided a highly effective and practical hydraulic recoil distributing device which is simple to assemble, maintain and replace if necessary; needing no costly seals or parts which must be manufactured to close tolerances as in most hydraulic devices.

It will be obvious to those skilled in the art that various changes may be made in the invention without departing from the spirit and scope thereof and therefore the in vention is not limited to the preferred embodiment which has been disclosed but only as indicated in the accompanying claims:

I claim:

1. A shock-absorbing device for a firearm comprising in combination a first member adapted to be secured to a firearm, a second member aligned with said first member and attached thereto for limited movement with respect to said first member in the general line of recoil between an extended and a retracted position, a flexible container having a first portion and a second portion separated by an abutment and having a restricted passageway connecting said first and said second portions, a liquid in said flexible container, said passageway positioned to control flow of the liquid in the container and to brake relative movement between said first and second members, resilient means urging said second member toward the extended position, and means cooperating with said first and second members to maintain the alignment thereof.

2. A firearm comprising in combination a buttstock, a movable buttplate member aligned therewith and attached thereto for limited displacement in the general line of recoil with respect thereto between an extended and retracted position, aligning means engaging said buttstock and buttplate member to maintain the relative attitude of said buttstock and buttplate member unchanged during the relative displacement therebetween, a shockabsorbing mechanism mounted between said buttstock and said movable buttplate member, said shock-absorbing mechanism comprising a flexible container having a first portion and a second portion separated by an abutment and having a restricted passageway connecting said first and second portions, a liquid in said flexible container, said abutment operative upon relative movement between said buttstock and said buttplate member to force liquid from one portion of the container to the other through said restricted passageway to brake such relative movement, means cooperating with said container to vary the rate of How of the liquid through said restricted passageway to vary said braking action.

3. A shock-absorbing device for a firearm comprising in combination a first member adapted to be secured to a firearm, a second member aligned with said first member and attached thereto for limited movement with respect to said first member in the general line of recoil between an extended and a retracted position, a flexible container holding a liquid, having a first portion and a second portion separated by an abutment and having a restricted passageway connecting said first and said second portions to control flow of the liquid in the container and to brake relative movement between said first and second members, resilient means urging said second member toward the extended position, and means cooperating with said first and second members to maintain the alignment thereof, said last-mentioned means comprising a force-equalizing linkage, said linkage having first and second levers having a first end connected to one of said members and having a portion near said second end in abutting engagement with said other member, said levers having interconnecting means positioned on said second ends thereof.

References Cited in the file of this patent UNITED STATES PATENTS 837,601 Behr Dec. 4, 1906 910,276 Easdale Jan. 19, 1909 1,351,141 Thompson Aug. 31, 1920 2,438,142 Brower Mar. 23, 1948 2,731,753 Mathieu Jan. 24, 1956 2,754,608 Stielfel July 17, 1956

Images