Fire control mechanism for a firearm

• US 5,615,507 A
• Filed: 06/07/1995
• Issued: 04/01/1997
• Est. Priority Date: 06/07/1995
• Status: Expired due to Term

• Current Assignee: Smith & Wesson Corporation (Smith & Wesson Brands, Inc.)
• Original Assignee: Thompson Intellectual Properties, Ltd.
• Inventors: French, Kendrick L.
• Primary Examiner(s): ELDRED, JOHN W
• Application Number:
  US08/483,197
• Time in Patent Office: 664 Days
• Field of Search: 42/70.05, 42/69.02, 89/144, 89/148
• US Class Current: 42/69.02
• CPC Class Codes: F41A 17/28 acting on the sear
• CPC Class Codes: F41A 17/56 Sear safeties, i.e. means for rendering ineffective an intermediate lever transmitting trigger movement to firing pin, hammer, bolt or sear F41A17/02 - F41A17/40 take precedence

Abstract

A locking mechanism for a firearm a striker which is slidably mounted in the breach end of the barrel of the firearm for movement between a rearward cock position and a forward firing position. The striker is biased toward the firing position and is moved to the cock position against the bias by an actuator. The fire control mechanism includes a trigger housing which is fixed to the breach end of the barrel and a trigger which is mounted for pivoting movement between a cocked position and a firing position. The sear is also mounted on a housing for pivoting movement between a striker holding position and a striker release position. The sear is effective to hold the striker in its cocked position and is, in turn, held in its regular holding position by the trigger. When the trigger is moved to its firing position, the sear is no longer supportive by the trigger and no longer able to hold the striker in its cocked position against the biasing means for the striker, which results in the movement of the striker toward its firing position. A locking mechanism is mounted on a trigger housing for selective actuation between an active state and an inactive state. When the locking mechanism is in its active state, the sears is prevented it from moving to its striker release position when the trigger is moved to its firing position. When the locking mechanism is in its inactive state, the sear is free to move to its striker release position when the trigger is moved to its firing position.

Claims

1. In a firearm having a barrel which a muzzle end and a breech end and a bore, the firearm also including a striker which has a downwardly facing notch and a forwardly facing lower edge surface which defines the rear edge of the notch, the striker being slidably mounted in the breech end of the barrel for movement between a rearward cocked position and a forward firing position, a striker spring for biasing the striker toward the firing position, and a striker actuator for moving the actuator to the rearward cocked position against the bias of the striker spring, a fire control mechanism comprising:

(a) a trigger housing which is fixed to the breech end of the barrel;

(b) a trigger which is mounted on the housing for pivoting movement about a first horizontal axis between a cocked position and a firing position, said trigger having an upwardly facing edge surface;

(c) a sear which is mounted on the housing for pivoting movement about a second horizontal axis between a striker holding position and a striker release position, said sear having an upper projection for entering said notch and engaging said forwardly facing edge surface when said striker is in its rearward cocked position and said sear is in its striker holding position, said sear having a forward projection for engaging the upwardly facing edge surface of said trigger when said sear is in its striker holding position and said trigger is in its cocked position to prevent said striker from being moved to its tiring position by said striker spring, said forward projection being out of engagement with said upwardly facing edge surface when said trigger is its firing position to enable said striker to be moved to its firing position by said striker spring;

(d) biasing means for biasing said trigger to its cocked position and said sear to its striker holding position, said biasing means being substantially weaker than said striker spring so that when said trigger is moved to its firing position, said sear is moved to its striker release position by said striker under the biasing influence of said striker spring to release the striker to its firing position under the biasing influence of said striker spring; and

(e) a locking mechanism which is mounted on said trigger housing for selective actuation between an active state and an inactive state, said locking mechanism being effective in its active state to engage said sear and prevent said sear from being moved to its striker release position by said striker when said trigger is moved to its firing position and to allow said sear to be moved to its striker release position when said trigger is moved to its firing position and said locking mechanism is in its inactive state, said locking mechanism comprising;

(1) a laterally extending projection which is fixed to said sear;

(2) a lock which is mounted on said trigger housing for movement between a locking position in which a portion of said lock obstructs said laterally extending projection to prevent said sear from moving to its firing position and a release position in which said sear is free to move to its firing position; and

(3) an actuator for selectively moving said lock to said locking position and to said release position.

2. In a firearm as recited in claim 1, wherein said lock is a lever which is mounted on said trigger housing for pivoting movement about a third horizontal axis and said actuator is a bell crank lever which is pivotally connected to said trigger housing, said bell crank lever having a first arm which is operatively connected to said lock and a second arm for engagement by a user'"'"'s finger.

3. In a firearm as recited in claim 2, wherein the connection between said first arm and said lock is a yoke connection.

4. In a firearm as recited in claim 2, wherein said bell crank lever has a third arm and said locking mechanism further comprises detent means which is operatively connected to said trigger housing and to said third arm to yieldingly maintain said lock in either of its locking and release positions.

5. In a firearm as recited in claim 2, wherein the laterally extending projection of said sear moves along an arc which is relatively close to said third horizontal and the portion of said lock which obstructs said laterally extending projection is located between said laterally extending projection and said third horizontal axis when said lock is in the locking position.

6. In a firearm as recited in claim 2, wherein said biasing means is a spring which engages said trigger and said sear for biasing said trigger to its cocked position and for biasing said sear to said striker holding position.

7. In a firearm as recited in claim 2, wherein said actuator is mounted for rotation about said second horizontal axis.

8. In a firearm as recited in claim 1, wherein said locking mechanism further comprises detent means for yieldingly maintaining said lock in either of its locking and release positions.