Classifications

• • 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
  • F41A21/00—Barrels; Gun tubes; Muzzle attachments; Barrel mounting means
  • F41A21/32—Muzzle attachments or glands
  • F41A21/36—Muzzle attachments or glands for recoil reduction ; Stabilisators; Compensators, e.g. for muzzle climb prevention
• • 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
  • F41A25/00—Gun mountings permitting recoil or return to battery, e.g. gun cradles; Barrel buffers or brakes
  • F41A25/10—Spring-operated systems

Definitions

• Present invention relates to an elastic oscillation damper to prevent natural oscillations which, when firing a shot, arise in a gun pipe having a muzzle brake, from propagation to a recoil brake for the gun pipe.
• the invention also concerns a damping device for a gun pipe with a muzzle brake, comprising a recoil brake and said oscillation damper.
• an object of the present invention is to provide an elastic oscillation damper for a damping device of the type initially described, to appreciably prevent the natural oscillations of the gun pipe from propagation to the recoil brake of the gun, when firing a shot.
• the invention concerns an elastic oscillation damper of the type initially described, being designed to be connected to the recoil brake and a gun pipe breeching in such a way that the force transfer coupling between the breeching and the recoil brake is reduced with respect to the natural oscillations of the gun pipe, when firing a shot;
• the oscillation damper according to the invention being characterized in that the dimenions of the oscillation damper are such that the damper along with the recoil brake form a damping device having a rigidity substantially less than the recoil brake alone and constituting an oscillatory system with a natural frequency substantially lower than that of said natural oscillations of the gun pipe, when firing a shot.
• the elastic oscillation damper consists of a plurality of Belleville springs, preferably of the same shape, and being assembled in such a number to form a spring column that at maximum deflection, the springs in all are capable of elastically absorbing the maximum recoil force to which the recoil brake may be exposed, without the internal shearing forces in each individual spring exceeding the limit of elasticity.
• the invention also conserns a damping device for a gun pipe having a muzzle brake; said device comprising a recoil brake, preferably in the form of a viscous damper, and an oscillation damper to prevent natural oscillations in the gun pipe when firing a shot, from propagation to the recoil brake; the oscillation damper being coupled to the recoil brake and a gun pipe breeching in such a way that the force transfer coupling between the breeching and the recoil brake is reduced with respect to said natural oscillations.
• a recoil brake preferably in the form of a viscous damper
• an oscillation damper to prevent natural oscillations in the gun pipe when firing a shot, from propagation to the recoil brake
• the oscillation damper being coupled to the recoil brake and a gun pipe breeching in such a way that the force transfer coupling between the breeching and the recoil brake is reduced with respect to said natural oscillations.
• the damping device is characterized in that the dimensions of the oscillation damper, preferably being designed as a column of Belleville springs, are such that the damping device as a whole has a rigidity substantially less than the recoil brake alone and forms an oscillatory system with a natural frequency substantially lower than that of the natural oscillations of gun pipe, when firing a shot.
• the substantially reduced rigidity of the damping device now causes parts of the recoil forces which previously were transferred- to the recoil brake, to be absorbed as inertial forces in the gun pipe and components connected thereto, at the same time as the fast oscillations of the gun pipe to a far lesser extent are transferred to the recoil brake due to the lower natural frequency of the system.
• connection of the elastic oscillation damper to the recoil brake and the gun pipe breeching is designed so that the oscillation damper is exposed mainly to compression, when firing a shot.
• a particularly preferred embodiment of the damping device according to the invention which is provided with a connection member for forced transfer from the gun pipe to a rod extending from one side of the connecting member to the recoil brake, when firing a shot, is characterized in that the elastic oscillation damper is mounted onto a portion of the rod to the recoil brake, which is on the other side of said connecting member; the recoil brake rod being movable in relation to the connecting member, preferably by loose guidance through the connecting member.
• Figure 1 illustrates a gun pipe having a prior art recoil brake
• Figure 2 shows a typical sequence of discharge force transfer from the gun pipe to the recoil brake in the embodiment of Figure 1
• Figure 3 is a cross sectional and a perspective view, respectively, of a Belleville spring in an oscillation damper according to present invention
• Figure 4 is an enlarged sectional view of Figure 1 showing the oscillation damper installed according to the inventio
• Figure 5 shows a sequence of the discharged force transfer from the gun pipe to the recoil brake with an oscillation damper installed as demonstrated in
• FIG. 1 shows a schematic outline of a gun pipe 1 provided with a muzzle brake 2 and a damping device constituted by a prior art recoil brake 3.
• the recoil brake 3 consists of a sylindrical hydraulic damper with piston and piston rod 6.
• a connecting member designed as an ear 4 is fixed to the cannon pipe breeching 5 for connection thereof to the rod 6 from the recoil brake, so that the recoiling parts of the gun is retarded by the recoil brake when firing the gun, the recoil brake rod 6 being permanently attached to the ear 4 by means of a lock nut 7.
• Figure 2 shows a typical oscillation sequence of the force which, when firing a shot, is transferred from the gun pipe 1 to the recoil brake 3 in an arrangement such as that shown in Figure 1.
• the horisontal axis is the time axis, while the vertical axis indicates the forces in kN.
• Recoil brakes in known damping devices of the kind shown in Figure 1 are in principle viscous dampers which serves to transform kinetic energy to thermal energy.
• an elastic oscillation damper e.g. a spring
• a visco-ela ⁇ tic damping device is achieved which according to the invention, is designed to attenuate the oscillating forces caused by the natural oscillation of the gun pipe.
• the natural frequency of this system is a function of the total rigidity incorporated in the oscillating system, including the co-oscillating mass. Both these quantities are difficult to determine, since both rigidity and mass are unevenly distributed across the system. However, to a certain degree the natural frequency may be estimated from a simplified calculation model. On this basis, the oscillation damper is dimensioned and tested so as to achieve a natural frequency which is well below the frequency of the gun pipe oscillations, which to the largest degree possible are to be prevented from transfer to the recoil brake.
• Figure 3 shows a cross section through a Belleville spring of an oscillation damper for the present object
• Figure 4 shows a series of such Belleville springs 10 assembled to form the desired oscillation damper.
• the large and small diameters a, b of the Belleville spring are determined by the space available on the location where it is to be mounted, i.e. on an extension 8 of the recoil brake rod 6. It is also possible to prepare an adapter for the installation of the springs therein, thereby avoiding the need for extended the recoil brake rod itself to obtain enough space for the column of springs.
• the momentary value of the recoil force varies between 0 and approx. 650 kN. Therefore, there will be no stretch in the springs of the oscillation damper and hence, it is sufficient to arrange springs only on one side of the ear 4, thereby exposing the springs to compression only, when firing a shot.
• a number of 50 - 60 springs mounted on the extension 8 of the recoil brake rod will give the oscillating system a natural frequency of 125 - 150 Hz, which is well below 400 Hz, i.e. the frequency of the force oscillations exerted on the recoil brake rod.
• Figure 5 shows the sequence of the recoil force which, when firing, is transferred from the gun pipe 1 to the recoil brake 3 in the damping device having an oscillation damper 9 mounted according to Figure 4.
• the vertical axis indicates the forces in kN and the horisontal axis the time in ms.
• the lauching is carried out with the same given type of shell, and the same propellant charge and gun pipe elevation as in the case demonstrated in Figure 2.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Vibration Dampers (AREA)
• Braking Arrangements (AREA)
• Buildings Adapted To Withstand Abnormal External Influences (AREA)
• Vibration Prevention Devices (AREA)
• Making Paper Articles (AREA)
• Fluid-Damping Devices (AREA)
• Audible-Bandwidth Dynamoelectric Transducers Other Than Pickups (AREA)
• Fuel-Injection Apparatus (AREA)
• Surgical Instruments (AREA)
• Portable Nailing Machines And Staplers (AREA)
• Inductance-Capacitance Distribution Constants And Capacitance-Resistance Oscillators (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=19894464

Family Applications (1)

Country Status (10)

Families Citing this family (21)

Citations (1)

Family Cites Families (3)

• 1991
  • 1991-09-16 NO NO913638A patent/NO173571C/no not_active IP Right Cessation
• 1992
  • 1992-09-08 CA CA002119273A patent/CA2119273C/en not_active Expired - Fee Related
  • 1992-09-08 ES ES92920472T patent/ES2098540T3/es not_active Expired - Lifetime
  • 1992-09-08 DK DK92920472.5T patent/DK0604557T3/da active
  • 1992-09-08 DE DE69217069T patent/DE69217069T2/de not_active Expired - Fee Related
  • 1992-09-08 WO PCT/NO1992/000143 patent/WO1993006427A1/en active IP Right Grant
  • 1992-09-08 US US08/211,014 patent/US5505118A/en not_active Expired - Fee Related
  • 1992-09-08 AT AT92920472T patent/ATE148221T1/de not_active IP Right Cessation
  • 1992-09-08 EP EP92920472A patent/EP0604557B1/en not_active Expired - Lifetime
• 1997
  • 1997-04-01 GR GR970400672T patent/GR3022998T3/el unknown

Patent Citations (1)

Also Published As

Similar Documents

Legal Events