US3417660A - Shock absorber for an automatic firearm - Google Patents

Shock absorber for an automatic firearm Download PDF

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Publication number
US3417660A
US3417660A US584413A US58441366A US3417660A US 3417660 A US3417660 A US 3417660A US 584413 A US584413 A US 584413A US 58441366 A US58441366 A US 58441366A US 3417660 A US3417660 A US 3417660A
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US
United States
Prior art keywords
cylinder
shock absorber
displacement
push rod
end wall
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US584413A
Inventor
Harbrecht Karl
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Rheinmetall Industrie AG
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Rheinmetall GmbH
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Publication date
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F7/00—Vibration-dampers; Shock-absorbers
    • F16F7/01—Vibration-dampers; Shock-absorbers using friction between loose particles, e.g. sand
    • F16F7/015—Vibration-dampers; Shock-absorbers using friction between loose particles, e.g. sand the particles being spherical, cylindrical or the like
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41—WEAPONS
    • F41A—FUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A3/00—Breech mechanisms, e.g. locks
    • F41A3/64—Mounting of breech-blocks; Accessories for breech-blocks or breech-block mountings
    • F41A3/78—Bolt buffer or recuperator means
    • F41A3/90—Fluid buffers

Definitions

  • this is achieved by means of a cover plate guided slidably in the cylinder and forming a confining surface for the displacement medium, the said cover plate being supported against the adjacent end wall of the cylinder by way of a spring.
  • the return of the displacement piston can take place in a substantially shorter time than is the case of the construction described in said patent referred to above, since the cover plate forming the forward confining surface for the displacement medium is supported resiliently in the direction of movement of the piston, i.e. in the direction of the front end wall of the cylinder.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Fluid-Damping Devices (AREA)
  • Chutes (AREA)
  • Vibration Dampers (AREA)

Description

Dec. 24, 1968 K. HARBRECHT SHOCK ABSORBER FOR AN AUTOMATIC FIREARM Filed Oct. 5, 1966 Inventor: K21 2 Har bFfi 672i W 44% zl f yi. 60%
United States Patent SHOCK ABSORBER FOR AN AUTOMATIC FIREARM Karl Harbrecht, Eisental, near Buhl, Germany, assignor to Firma Rheinmetall G.m.b.H., Dusseldorf, Germany Filed Oct. 5, 1966, Ser. No. 584,413
Claims priority, application Germany, Oct. 8, 1965,
R 41,719 1 Claim. (Cl. 89-498) ABSTRACT OF THE DISCLDSURE A shock absorber for an automatic firearm having a cylinder containing a plurality of pellets and a push rod with a displacement piston in the pellets operative under spring action against an end wall of the cylinder and a cover plate in contact with the pellets.
The invention relates to shock absorbers for automatic firearms comprising a displacement piston arranged on a buffer pin or a push rod and with a passage surrounding it, the piston being slidable in a cylinder filled with a displacement medium in the form of pellets, as described in U.S. Patent No. 3,251,270 of May 17, 196 6.
In many cases, particularly when the shock absorber is employed as a breech block buffer, it is desirable that there be a substantially smaller damping resistance to the return stroke of the displacement piston (on counterrecoil of the breech block) than in the opposite direction of movement of the piston.
According to the present invention, this is achieved by means of a cover plate guided slidably in the cylinder and forming a confining surface for the displacement medium, the said cover plate being supported against the adjacent end wall of the cylinder by way of a spring. In this case, the return of the displacement piston can take place in a substantially shorter time than is the case of the construction described in said patent referred to above, since the cover plate forming the forward confining surface for the displacement medium is supported resiliently in the direction of movement of the piston, i.e. in the direction of the front end wall of the cylinder. Because of this, moreover, the advantage is obtained that in those constructions in which a return spring is provided for restoring the piston to its initial position only a comparatively weak return spring is now required, this having an advantageous eifect in regard to the efforts made to achieve small dimensions for the damping device.
In a preferred embodiment of the invention, the return spring is arranged between the front end wall of the cylinder and the front end of the buffer pin and the latter is moreover guided in the end wall of the cylinder and in the cover plate.
As a further advantageous development of the invention, in a shock absorber having a hollow buffer pin for receiving a return spring, the displacement piston may be arranged at the inner end of the buffer pin and be guided with the latter on a guide tube fixed to the opposite wall of the cylinder and receiving the return spring. In this way, particularly favourable structural dimensions for the damping device and an extremely stable guiding action for the displacement piston are obtained.
Three embodiments of the invention will now be described in greater detail with reference to the accompanying drawings in which FIGS. 1, 2 and 3 are each a longitudinal section of three embodiments.
The cylinder 1 of a breech block buffier contains a 3,417,660 Patented Dec. 24, 1968 displacement medium 2 consisting of solid, pellet-shaped bodies, for example steel pellets with a diameter of about 1 mm. The cylinder 1 is only partly filled with the displacement medium, a cover plate 3 forming a forward confining surface for the displacement medium. The cover plate 3 is supported by a spring 4 acting against the front end wall 5 of the cylinder. The end wall 5 is secured to the cylinder in a suitable manner; it is advantageously screwed in so that the initial tension of the spring 4 and thus the characteristic of the buffer device can be varied. A displacement piston 7 arranged on a push rod 6 is guided slidably in that part of the cylinder space which is filled with the displacement medium. The displacement piston has a smaller outer diameter than the internal diameter of the cylinder, so that there is an annularpassage for the displacement medium.
In the embodiment shown in FIG. 1, a return spring 6 is arranged between the front end wall 5 and a collar 9 provided at the front end of the push rod 6. In the embodiment shown in FIG. 2, the return spring 8 is arranged inside the hollow push rod and a guide tube 10 serving to guide the displacement piston and fixed to the opposite Wall of the cylinder. This design permits particularly small dimensions and damping movements which are large in relation thereto.
While FIGS. 1 and 2 show embodiments of the invention in which a return spring 8 is provided for returning the push rod, FIG. 3 shows a construction without a return spring. In this case, the push rod 6 extends through both end walls of the cylinder and is guided in them. A construction of this kind will be chosen in the case of damping devices with a forced movement of the push rod, i.e. in those constructions in which the push rod is coupled to a moving mass.
What is claimed is:
1. A shock absorber for an automatic firearm comprising in combination a cylinder containing a displacement medium in the form of pellets, an end wall on said cylinder, a push rod extending into the cylinder, a displacement piston arranged on the push rod, said displacement piston being slidable with clearance inside said cylinder, a cover plate slidable within said cylinder, said cover plate forming a confining surface for said displacement medium, resilient means supporting said cover plate against the displacement medium and provided adjacent said end wall of said cylinder and a resilient return means for restoring said displacement piston to a forward end position in said cylinder, said resilient return means being arranged between said end wall of said cylinder and the front end of said push rod, and said push rod being guided in said end wall and in said cover plate.
References Cited UNITED STATES PATENTS 2,460,116 1/1949 Bazley 188-401 X 3,105,411 10/ 1963 Browning 89-198 X 2,570,854 10/1951 Pierce 188101 X 3,251,270 5/1966 Seifried 89198 X FOREIGN PATENTS 1,188,479 3/1965 Germany.
BENJAMIN A. BORCHELT, Primary Examiner. S. C. BENTLEY Assistant Examiner.
U.S. Cl. X.R. 188l01
US584413A 1965-10-08 1966-10-05 Shock absorber for an automatic firearm Expired - Lifetime US3417660A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DER41719A DE1261022B (en) 1965-10-08 1965-10-08 Shock absorbers for automatic firearms

Publications (1)

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US3417660A true US3417660A (en) 1968-12-24

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US584413A Expired - Lifetime US3417660A (en) 1965-10-08 1966-10-05 Shock absorber for an automatic firearm

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US (1) US3417660A (en)
BE (1) BE687934A (en)
DE (1) DE1261022B (en)
ES (1) ES332418A2 (en)
GB (1) GB1109969A (en)
NL (1) NL6614191A (en)

Cited By (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3938625A (en) * 1973-03-19 1976-02-17 Interatom, Internationale Atomreaktorbau Gmbh Vibration damping device, especially for protecting pipelines from earthquakes
US4126080A (en) * 1977-04-29 1978-11-21 The United States Of America As Represented By The Secretary Of The Army High velocity anti-surge spring assembly
EP0010509A2 (en) * 1978-08-11 1980-04-30 CENTRE STEPHANOIS DE RECHERCHES MECANIQUES HYDROMECANIQUE ET FROTTEMENT Société dite: Firearm with electric firing mechanism and process for its operation; ammunition and primers therefor
US4244273A (en) * 1978-12-04 1981-01-13 Langendorfer Plastics Corporation Rifle modification
US4307794A (en) * 1978-04-17 1981-12-29 Institut Chemii Przemyslowej Apparatus for absorbing mechanical energy, in particular energy of very strong shocks
US4776436A (en) * 1987-05-14 1988-10-11 Geologoproutshvatelno Predpriyatie Face shock absorber
US5027715A (en) * 1990-02-12 1991-07-02 Mid-West Conveyor Company, Inc. Shock absorbing carrier
US5067414A (en) * 1990-02-12 1991-11-26 Mid-West Conveyor Company, Inc. Self-adjusting shock absorbing carrier
US5069110A (en) * 1991-04-09 1991-12-03 Menck Thomas W Impact buffering recoil mechanism
US5450931A (en) * 1993-06-24 1995-09-19 Hitachi, Ltd. Vibration control apparatus
US5491917A (en) * 1991-11-20 1996-02-20 Etienne Lacroix Tous Artifices S.A. Weapons system having a shock absorber
US5632206A (en) * 1995-07-14 1997-05-27 Mid-West Conveyor Company, Inc. Adjustable cushioned tow bar for power and free conveyor
US5941005A (en) * 1998-07-25 1999-08-24 O.F. Mossberg & Sons, Inc. Safety and bolt assembly system for firearms
US5983549A (en) * 1998-07-24 1999-11-16 O. F. Mossberg & Sons, Inc. Inertial cycling system for firearms
WO2001079725A1 (en) * 2000-04-12 2001-10-25 Eurocopter Damping structure and uses
US20030221350A1 (en) * 2002-03-05 2003-12-04 Giuseppe Pescini Loading device for kinetic operation automatic or semi-automatic rifles
US7213498B1 (en) * 2002-05-07 2007-05-08 Davies Robert B Rifle
US20090133570A1 (en) * 2007-11-23 2009-05-28 Diehl Bgt Defence Gmbh & Co. Kg Weapon Barrel and Damping Device
US20120024646A1 (en) * 2009-04-09 2012-02-02 Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) Damping structure
US8448927B1 (en) * 2008-09-24 2013-05-28 Lockheed Martin Corporation Shock attenuation device and method
US8468729B1 (en) * 2010-01-18 2013-06-25 Primary Weapons Buffer tube
USD685873S1 (en) 2012-01-05 2013-07-09 Ra Brands, L.L.C. Recoil reducer
CN103322109A (en) * 2013-07-18 2013-09-25 中国科学院上海应用物理研究所 Rolling ball damper buffer
DE102012022682A1 (en) * 2012-11-21 2014-05-22 Rheinmetall Waffe Munition Gmbh A firearm with a mass-relievable sealant
CN104632990A (en) * 2014-12-31 2015-05-20 中国人民解放军军械工程学院 Solid particle damper device
US20150192380A1 (en) * 2013-01-14 2015-07-09 Daniel Hilsabeck Recoil Reducing Spring System
CN105715723A (en) * 2016-03-29 2016-06-29 上海理工大学 Damping device
USD780875S1 (en) 2015-11-18 2017-03-07 Primary Weapons Buffer tube
CN106917840A (en) * 2017-04-05 2017-07-04 武汉科技大学 A kind of obstructive piston type granule damper
CN107165969A (en) * 2017-06-27 2017-09-15 武汉科技大学 Screw piston bar granule damper
US9927192B1 (en) 2016-01-19 2018-03-27 Primary Weapons Buffer tube locking plate
CN109477539A (en) * 2016-06-21 2019-03-15 Ｋｙｂ株式会社 Damper
US10281233B2 (en) 2011-09-30 2019-05-07 Ra Brands, L.L.C. Recoil reducer
CN113586656A (en) * 2021-07-21 2021-11-02 江苏力科丹普机械技术有限公司 Energy-consuming spring composite particle damper
CN114776120A (en) * 2022-04-27 2022-07-22 北京工业大学 Triangular hysteretic damping device with negative stiffness characteristic

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5337385Y2 (en) * 1973-01-27 1978-09-11
FR2672652B1 (en) * 1991-02-12 1995-02-03 Lacroix E Tous Artifices DAMPING SYSTEM ESPECIALLY FOR WEAPON SYSTEMS.
DE4128465C1 (en) * 1991-08-28 1993-02-25 Mercedes-Benz Aktiengesellschaft, 7000 Stuttgart, De
RU2523722C2 (en) * 2012-09-27 2014-07-20 Игорь Всеволдович Никишин Damping device
CN112032235A (en) * 2020-09-01 2020-12-04 云南电网有限责任公司 Internal friction type damper

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2460116A (en) * 1945-08-24 1949-01-25 Gen Electric Control device
US2570854A (en) * 1949-05-18 1951-10-09 Daniel H Pierce Self-adjusting tappet for internalcombustion engines
US3105411A (en) * 1961-07-24 1963-10-01 Browning Ind Inc Recoil absorbing mechanism
DE1188479B (en) * 1963-06-21 1965-03-04 Rheinmetall Gmbh Lock buffer for automatic firearms
US3251270A (en) * 1963-03-09 1966-05-17 Rheinmetall Gmbh Recoil absorber for an automatic weapon

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2460116A (en) * 1945-08-24 1949-01-25 Gen Electric Control device
US2570854A (en) * 1949-05-18 1951-10-09 Daniel H Pierce Self-adjusting tappet for internalcombustion engines
US3105411A (en) * 1961-07-24 1963-10-01 Browning Ind Inc Recoil absorbing mechanism
US3251270A (en) * 1963-03-09 1966-05-17 Rheinmetall Gmbh Recoil absorber for an automatic weapon
DE1188479B (en) * 1963-06-21 1965-03-04 Rheinmetall Gmbh Lock buffer for automatic firearms

Cited By (50)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3938625A (en) * 1973-03-19 1976-02-17 Interatom, Internationale Atomreaktorbau Gmbh Vibration damping device, especially for protecting pipelines from earthquakes
US4126080A (en) * 1977-04-29 1978-11-21 The United States Of America As Represented By The Secretary Of The Army High velocity anti-surge spring assembly
US4307794A (en) * 1978-04-17 1981-12-29 Institut Chemii Przemyslowej Apparatus for absorbing mechanical energy, in particular energy of very strong shocks
EP0010509A2 (en) * 1978-08-11 1980-04-30 CENTRE STEPHANOIS DE RECHERCHES MECANIQUES HYDROMECANIQUE ET FROTTEMENT Société dite: Firearm with electric firing mechanism and process for its operation; ammunition and primers therefor
EP0010509A3 (en) * 1978-08-11 1980-12-10 CENTRE STEPHANOIS DE RECHERCHES MECANIQUES HYDROMECANIQUE ET FROTTEMENT Société dite: Firearm with electric firing mechanism and process for its operation; ammunition and primers therefor
FR2460468A2 (en) * 1978-08-11 1981-01-23 Stephanois Rech Mec ELECTRICALLY CONTROLLED ARM, METHOD OF OPERATION AND AMMUNITION USED
US4244273A (en) * 1978-12-04 1981-01-13 Langendorfer Plastics Corporation Rifle modification
US4776436A (en) * 1987-05-14 1988-10-11 Geologoproutshvatelno Predpriyatie Face shock absorber
US5027715A (en) * 1990-02-12 1991-07-02 Mid-West Conveyor Company, Inc. Shock absorbing carrier
US5067414A (en) * 1990-02-12 1991-11-26 Mid-West Conveyor Company, Inc. Self-adjusting shock absorbing carrier
US5069110A (en) * 1991-04-09 1991-12-03 Menck Thomas W Impact buffering recoil mechanism
US5491917A (en) * 1991-11-20 1996-02-20 Etienne Lacroix Tous Artifices S.A. Weapons system having a shock absorber
US5450931A (en) * 1993-06-24 1995-09-19 Hitachi, Ltd. Vibration control apparatus
US5632206A (en) * 1995-07-14 1997-05-27 Mid-West Conveyor Company, Inc. Adjustable cushioned tow bar for power and free conveyor
US5983549A (en) * 1998-07-24 1999-11-16 O. F. Mossberg & Sons, Inc. Inertial cycling system for firearms
US5941005A (en) * 1998-07-25 1999-08-24 O.F. Mossberg & Sons, Inc. Safety and bolt assembly system for firearms
WO2001079725A1 (en) * 2000-04-12 2001-10-25 Eurocopter Damping structure and uses
US20030098389A1 (en) * 2000-04-12 2003-05-29 Dussac Marc Francis Vincent Damping structure and applications
EP1447588A2 (en) * 2000-04-12 2004-08-18 Eurocopter Suspension system for gearbox
EP1447588A3 (en) * 2000-04-12 2005-01-19 Eurocopter Suspension system for gearbox
US6935472B2 (en) 2000-04-12 2005-08-30 Eurocopter Damping structure and applications
US20050199458A1 (en) * 2000-04-12 2005-09-15 Eurocopter Damping structure and applications
US7104372B2 (en) 2000-04-12 2006-09-12 Eurocopter Damping structure and applications
US20030221350A1 (en) * 2002-03-05 2003-12-04 Giuseppe Pescini Loading device for kinetic operation automatic or semi-automatic rifles
US7213498B1 (en) * 2002-05-07 2007-05-08 Davies Robert B Rifle
US8176671B2 (en) * 2007-11-23 2012-05-15 Diehl Bgt Defence Gmbh & Co. Kg Weapon barrel and damping device
US20090133570A1 (en) * 2007-11-23 2009-05-28 Diehl Bgt Defence Gmbh & Co. Kg Weapon Barrel and Damping Device
US8448927B1 (en) * 2008-09-24 2013-05-28 Lockheed Martin Corporation Shock attenuation device and method
US20120024646A1 (en) * 2009-04-09 2012-02-02 Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) Damping structure
US8468729B1 (en) * 2010-01-18 2013-06-25 Primary Weapons Buffer tube
US10281233B2 (en) 2011-09-30 2019-05-07 Ra Brands, L.L.C. Recoil reducer
USD685873S1 (en) 2012-01-05 2013-07-09 Ra Brands, L.L.C. Recoil reducer
DE102012022682A1 (en) * 2012-11-21 2014-05-22 Rheinmetall Waffe Munition Gmbh A firearm with a mass-relievable sealant
DE102012022682B4 (en) * 2012-11-21 2015-02-19 Rheinmetall Waffe Munition Gmbh A firearm with a mass-relievable sealant
DE102012022682B8 (en) * 2012-11-21 2015-05-13 Rheinmetall Waffe Munition Gmbh Tube weapon with a mass-locking locking system
US20150192380A1 (en) * 2013-01-14 2015-07-09 Daniel Hilsabeck Recoil Reducing Spring System
CN103322109B (en) * 2013-07-18 2015-11-25 中国科学院上海应用物理研究所 Spin damping buffer
CN103322109A (en) * 2013-07-18 2013-09-25 中国科学院上海应用物理研究所 Rolling ball damper buffer
CN104632990A (en) * 2014-12-31 2015-05-20 中国人民解放军军械工程学院 Solid particle damper device
USD780875S1 (en) 2015-11-18 2017-03-07 Primary Weapons Buffer tube
US9927192B1 (en) 2016-01-19 2018-03-27 Primary Weapons Buffer tube locking plate
CN105715723A (en) * 2016-03-29 2016-06-29 上海理工大学 Damping device
CN109477539A (en) * 2016-06-21 2019-03-15 Ｋｙｂ株式会社 Damper
CN106917840A (en) * 2017-04-05 2017-07-04 武汉科技大学 A kind of obstructive piston type granule damper
CN106917840B (en) * 2017-04-05 2023-03-21 武汉科技大学 Obstructive piston type particle damper
CN107165969A (en) * 2017-06-27 2017-09-15 武汉科技大学 Screw piston bar granule damper
CN107165969B (en) * 2017-06-27 2019-10-08 武汉科技大学 Screw piston bar granule damper
CN113586656A (en) * 2021-07-21 2021-11-02 江苏力科丹普机械技术有限公司 Energy-consuming spring composite particle damper
CN114776120A (en) * 2022-04-27 2022-07-22 北京工业大学 Triangular hysteretic damping device with negative stiffness characteristic
CN114776120B (en) * 2022-04-27 2023-10-03 北京工业大学 Triangle hysteresis damping device with negative rigidity characteristic

Also Published As

Publication number Publication date
GB1109969A (en) 1968-04-18
BE687934A (en) 1967-03-16
ES332418A2 (en) 1967-07-16
DE1261022B (en) 1968-02-08
NL6614191A (en) 1967-04-10

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