Locking device

A locking device is constituted by: a casing; a cover fastened to the casing into a unit construction; a latch plate for latching a striker, the latch plate being rotatably supported by the casing and the cover; a locking plate being rotatably supported by the casing and the cover, the locking plate locking the latch plate in its turn, thereby to ensure the latching of the striker by the latch plate; locking-state removal means for removing the locking of the striker by the latch plate by turning the locking plate; and a striker pressing plate, rotatably supported by the cover, for pressing the striker against the latch plate in a state that the latch plate 16 is locked in its turn.

What is claimed is:

1. A locking device comprising:

a casing;

a cover fastened to said casing and forming a striker guide recess cooperating with said casing;

a latch plate for locking a striker, said latch plate being rotatably supported by said casing and said cover;

a locking plate being rotatably supported by said casing and said cover, said locking plate locking said latch plate in its turn, thereby to ensure a locking of said striker by said latch plate;

locking-state removal means for removing the locking of said striker by said latch plate by turning said locking plate;

interactive turning means for interactively turning said locking plate and said striker pressing plate within a predetermined region; and

a striker pressing plate, rotatably supported by said cover for pressing said striker against said latch plate in a state that said latch plate is locked in its turn,

wherein said interactive turning means is a link member coupled at one end with said locking plate and at an other end with said striker pressing plate.

2. The locking device according to claim 1, in which said link member includes a protruded piece for preventing said link member per se from slipping off from said locking plate and said striker pressing plate.

3. A locking device comprising:

a casing;

a cover fastened to said casing and forming a striker guide recess cooperating with said casing;

a latch plate for locking a striker, said latch plate being rotatably supported by said casing and said cover;

a locking plate being rotatable supported by said casing and said cover, said locking plate locking said latch plate in its turn, thereby to ensure a locking of said striker by said latch plate;

locking-state removal means for removing the locking of said striker by said latch plate by turning said locking plate; and

a striker pressing plate, rotatable supported by said cover for pressing said striker against said latch plate in a state that said latch plate is locked in its turn,

wherein said striker pressing plate has an engaging protrusion and said cover has a bore engaged with said engaging protrusion so that said striker pressing plate is directly supported by said cover.

4. A locking device comprising:

a casing;

a cover fastened to said casing and forming a striker guide recess cooperating with said casing;

a latch plate for locking a striker, said latch plate being rotatable supported by said casing and said cover;

a locking plate being rotatably supported by said casing and said cover, said locking plate locking said latch plate in its turn, thereby to ensure a locking of said striker by said latch plate;

locking-state removal means for removing the locking of said striker by said latch plate by turning said locking plate; and

a striker pressing plate, rotatable supported by said cover for pressing said striker against said latch plate in a state that said latch plate is locked in its turn,

wherein said cover has a guide slit and said striker pressing plate has an engaging shaft inserted into and being movable along said guide slit.

5. The locking device according to claim 4, wherein said engaging shaft has a curved piece formed at a tip end thereof.

6. A locking device comprising:

a casing;

a cover fastened to said casing and forming a striker guide recess cooperating with said casing;

a latch plate for locking a striker, said latch plate being rotatably supported by said casing and said covery;

a locking plate being rotatably supported by said casing and said cover, said locking plate locking said latch plate in its turn, thereby to ensure a locking of said striker by said latch plate;

locking-state removal means for removing the locking of said striker by said latch plate by turning said locking plate;

a striker pressing plate, rotatable supported by said cover for pressing said striker against said latch plate in a state that said latch plate is locked in its turn; and

a plate spring fixed on said cover at a first end thereof, said striker pressing plate having a spring receiving part for receiving a second end of said plate spring.

7. A locking device for use in combination with a striker, comprising:

a casing and a cover including a striker guide recess;

a latch plate rotatably supported between said casing and said cover and biased toward a first position; said latch plate further comprising a striker receiving recess and a first engaging part which overlaps said striker guide recess when said first engaging part is in said first position;

a locking plate rotatably supported between said casing and said cover, said locking plate including a second engaging part and said locking plate being in a first position;

a striker pressing plate, rotatably supported between said casing and said cover;

a lock removal rod rotatably attached to said locking plate; and

a spring coupling said latch plate and said locking plate;

wherein sad striker is adapted to enter said striker guide recess to contact said first engaging part and rotate said latch plate to a second position wherein said striker receiving recess prevents movement of the striker out of said striker guide recess,

wherein a rotation of said latch plate to said second position rotates said striker pressing plate and said locking plate into a position wherein said striker pressing plate, said locking plate, and said latch plate are all in a locked state,

wherein a predetermined movement of said lock removal rod rotates said locking plate and terminates said locked state, thereby allowing said latch plate to assume said first position and allowing egress of the striker from said striker guide recess, and wherein said spring biases each of said latch plate and said locking plate in an opening direction.

8. The locking device according to claim 7, wherein said striker pressing plate has an engaging protrusion and said cover has a bore engaged with said engaging protrusion so that said striker pressing plate is directly supported by said cover.

9. The locking device according to claim 7, wherein said cover has a guide slit and said striker pressing plate has an engaging shaft inserted into and being movable along said guide slit.

10. The locking device according to claims 9, wherein said engaging shaft has a curved piece formed at a tip end thereof.

11. The locking device according to claim 7, further comprising a plate spring fixed on said cover at a first end thereof and said striker pressing plate has a spring receiving part for receiving a second end of said plate spring.

12. A locking device according to claim 1, wherein said one end of said link member is rotatably coupled with said locking plate, and said other end of said link member is slidably coupled with said striker pressing plate.

13. A locking device according to claim 12, wherein said other end of said link member is slidably disposed in an elongated hole formed in said striker pressing plate.

14. A locking device according to claims 12, wherein said other end of said link member is slidably disposed in a groove formed in said striker pressing plate.