Dual rate firing mechanism
AssigneeThe United States of America as represented by the Secretary of the Army
InventorHenry P. Swieskowski
Life of this patent
Estimating the term…
Abstract
A dual rate of fire mechanism in an automatic weapon absorbs and dissipates portion of the recoil energy to produce a slow firing rate and inactivates the energy absorbing elements to produce a rapid firing rate. Compression of a recoil spring stores the recoil energy of the weapon bolt and normally returns substantially all of the energy to the bolt in a counter recoil portion of the cycle. In slow firing mode, some of the energy stored in the recoil spring is dissipated in a positioning spring thus providing less energy to the counter recoil action and slowing the rate at which succeeding rounds are fired.
Claims6
A dual-rate firing mechanism for an automatic weapon of the type having a bolt driven in a recoil action and returned in a counter recoil action, comprising:
- means for storing energy of said bolt during said recoil action and for returning at least part of the stored energy to said bolt during said counter recoil action,
- said means for storing energy including a recoil spring having first and second ends and a spring constant, means for applying kinetic energy of said bolt to said first end, and means for holding said second end stationary whereby said kinetic energy is transformed into spring potential energy in said recoil spring,
- said means for holding said second end stationary including a mass in abutment with said second end and a sear effective to substantially latch said mass against displacement while said kinetic energy is being transformed,
- means for selectively dissipating a portion of the stored energy during said said recoil action whereby less than substantially all of said stored energy remains for return to said bolt during said counter recoil action,
- said means for selectively dissipating including a positioning spring having a second spring constant effective to urge said mass in a direction opposite to the direction of applying said kinetic energy to said recoil spring, and means for releasing said mass from latching by said sear after a predetermined amount of said kinetic energy is transformed in said recoil spring whereby a portion of the stored kinetic energy is dissipated in moving said mass against said positioning spring.
A dual-rate firing mechanism for an automatic weapon comprising:
- a housing having first and second ends;
- an abutment at said first end of said housing;
- a plunger protruding from said second end of said housing;
- a bolt to which kinetic energy is imparted by firing said automatic weapon, said kinetic energy being effective to impact said bolt upon said plunger and to tend to drive said plunger into said housing;
- a recoil spring in said housing having a first end in abutment with said plunger;
- a positioning spring having a first end in contact with said abutment;
- a second end of said recoil spring and a second end of said positioning spring being mutually opposed;
- said recoil spring and said positioning spring being normally equally preloaded by the opposition therebetween;
- a sear having first and second positions;
- said sear being effective when in its first position to hold said second end of said recoil spring stationary during at least part of driving said plunger by said bolt whereby said kinetic energy of said bolt is transformed into spring potential energy of said recoil spring;
- said sear being effective when in its second position to release said second end of said recoil spring whereby equilibrium between opposing forces in said recoil spring and said positioning spring is attained;
- and
- means for moving said sear from its first position to its second position at a predetermined time after said bolt begins driving said plunger.
Dependencies are inferred from the claim text.