Belt buckle

A belt buckle which includes a base frame fastened to a lead end of a belt, the base frame having a locating plate with a notch, a holder frame fastened to the base frame, the holder frame having a chamber and a front opening disposed in communication with the chamber, a locking mechanism pivoted to the holder frame in its front opening and moved between a locking position where the locking mechanism is moved into the notch on the locating plate to hold down a tail end of the belt, and an unlocking position where the locking mechanism is moved out of the notch on the locking plate to release the tail end of the belt, and a release control unit mounted in the chamber of the holder frame and controlled to move the locking mechanism from the locking position to the unlocking position.

BACKGROUND OF THE INVENTION 
The present invention relates to belt buckles, and more particularly to 
such a belt buckle which comprises a base frame fixed to a lead end of a 
belt, a holder frame fastened to the base frame, a locking mechanism 
adapted to lock a tail end of the belt, and a release control unit 
controlled to release the locking mechanism. 
U.S. Pat. No. 4,699,155 discloses a belt buckle which comprises a base 
frame fastened to the lead end of the belt, a locking mechanism mounted in 
holder means on the base frame and adapted to lock the tail end of the 
belt. When the tail end of the belt is inserted into the base frame, the 
locking mechanism allows the tail end of the belt to pass. When the tail 
end of the belt is moved backwards, the locking mechanism engages a 
serrated portion on the back side of the tail end of the belt, therefore 
the tail end of the belt is stopped from backward movement. When to 
release the locking mechanism from the serrated portion of the tail end of 
the belt, the base frame of the buckle must be turned through a certain 
angle relative to the belt. This release control procedure is inconvenient 
to perform. Further, when turning the base frame relative to the belt, the 
abdomen may feel uncomfortable. 
SUMMARY OF THE INVENTION 
The present invention has been accomplished to provide a belt buckle which 
eliminates the aforesaid drawbacks. According to one aspect of the present 
invention, the belt buckle comprises a locking mechanism mounted in a 
holder frame on a base frame thereof and forced by spring means to lock 
the belt, and a release control unit mounted on the holder frame and 
conveniently controlled to release the locking mechanism. According to 
another aspect of the present invention, the locking mechanism comprises a 
locking lever forced by a spring to lock the belt; the release control 
unit comprises a control bolt supported on a spring, and a pressure block 
fastened to the bottom end of the control bolt, the pressure block being 
forced to move the locking lever out of the locking position when the 
control bolt is pressed down.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to FIGS. 1 and 2, a belt buckle in accordance with the present 
invention is generally comprised of a base frame 1, a holder frame 2, a 
locking mechanism 3, and a release control unit 4. The base frame 1 
comprises a locating plate 11 at one end, and a clamp 13 at an opposite 
end adapted to secure a lead end of a belt to the base frame 1. The 
locating plate 11 has a notch 12. The locking mechanism 3 is comprised of 
a pivot 31, a locking lever 32, and a spring 33. The locking lever 32 
comprises a pivot hole 321 on the middle, a tooth 322 at one end, and an 
arched handle 323 at an opposite end. The holder frame 2 comprises a front 
opening 21, two screw holes 22;22 aligned at two opposite sides of the 
front opening 21, a stub rod 211 disposed in the front opening 21 and 
adapted to hold the spring 33 of the locking mechanism 3, a hole 231, a 
chamber 23 disposed in communication between the front opening 21 and the 
hole 231, a bolt hole 24 disposed in parallel to the pivot hole 22 and in 
communication with the chamber 23, and a coupling wall 25. The release 
control unit 4 is comprised of a control bolt 41, a spring 42, and a 
pressure block 43. The pressure block 43 has a bevel bottom edge 431. The 
pivot 31 is mounted in the pivot holes 22;22' on the holder frame 2 and 
the pivot hole 321 on the locking lever 32 and transversely connected to 
the front end of the base frame 1 by screws 14. The coupling wall 25 of 
the holder frame 2 is forced into engagement with the locating plate 11 of 
the base frame 1. The locking lever 32 is turned about the pivot 31 in the 
front opening 21, permitting the tooth 322 to be moved in and out of the 
notch 12 on the locating plate 11. The spring 33 is mounted on the stub 
rod 211 inside the front opening 21 of the holder frame 2, and imparts an 
outward pressure to the locking lever 32, causing the tooth 322 of the 
locking lever 32 to be forced into the notch 12 on the locating plate 11. 
The control bolt 41 is mounted in the bolt hole 24. The spring 42 is 
mounted in the bolt hole 24 around the control bolt 41, and imparts an 
outward pressure to the control bolt 41. The pressure block 43 is fastened 
to the bottom end 411 of the control bolt 41 and suspended in the chamber 
23. 
Referring to FIGS. 3 and 4, when the tail end of the belt 5 is inserted 
into the base frame 1, the serrated portion 51 at the back side of the 
belt 5 is moved over the tooth 322 of the locking lever 32. When the belt 
5 is pulled backwards to remove its tail end from the base frame 1, the 
serrated portion 51 becomes forced into engagement with the tooth 322 of 
the locking lever 32, and therefore the tail end of the belt 5 is 
prohibited from a backward movement. When the bolt 41 is depressed, the 
pressure block 43 is moved forwards to force its bevel bottom edge 43 
against the arched handle 323 of the locking lever 32, thereby causing the 
locking lever 32 to turn about the pivot 31 and to lift the tooth 322 from 
the serrated portion 51 on the belt 5, and therefore the tail end of the 
belt 5 is released and can be removed from the base frame 1. When the 
control bolt 41 is released from the hand, the spring 42 immediately 
forces the control bolt 41 outwards to its former position.