JPH08326385A - Unlocking position restraint type latch device - Google Patents

Abstract

PURPOSE: To restrain a latch bolt surely in an unlocking position by a simple operation while reducing substantially a risk of dishonest unlocking by an unauthorized person. CONSTITUTION: A latch bolt 6 is slidably urged by a spring 3 in the direction of engaging a lock hole 5, and a lock lever 8 received in a slit groove of the latch bolt 6 is supported to rotatably go in and out of the slit groove and urged rotatably by the spring 3 in the direction of plunging the lock lever 8 into the slit groove. A case 2 is provided with a key hole 40 along the direction of moving an operating part 11 of the lock lever 8. The front face portion of the operating part 11 is provided with an escape groove part 45 facing the key hole 40, and a pair of a groove receiving parts are provided in the front end of the key hole 40. The tip end of an operating projection 39 of a key 38 is provided with a pair of thrust parts. When the operating part 11 of the lock lever 8 is pushed by the key 38 to slide backward to the unlocking position, the tip surface 8a of the lock lever 8 is adapted to abut against the hole edge 5a of a lock hole 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a latch device for locking a door to a fixed frame such as an electric equipment storage box.

[0002]

2. Description of the Related Art In a conventional latch device for locking a door to a fixed frame, a latch bolt is slidably housed in a case fixed to the door, a lock hole is provided in the fixed frame, and the lock is provided. The latch bolt is slid and urged by a spring in the direction of engagement with the hole, and by rotating the lever handle or knob from the front side of the door, the latch bolt is retracted and slid to the unlocked position. Is performed in a state where the latch bolt is restrained at the unlocking position.

When the height of the door is large, it is necessary to lock the door at several places, but until the last latch device is unlocked, a plurality of latches that have been unlocked by then are operated. It is virtually impossible for one person to hold the latch bolt in the unlocked position by holding the lever handle or knob on the entire device.

Further, since the operation portion of the latch bolt is projected into the space on the front side of the case, there is a high risk that an unauthorized person will operate the latch bolt by unauthorized person to unlock it. is there.

[0005]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to simplify the spring structure, to accurately restrain the latch bolt in the unlocked position by a simple operation, and to lock the latch bolt by an unauthorized person in a mischievous manner. It is an object of the present invention to provide a latch device in which the risk of the lever being operated arbitrarily and being unlocked illegally is greatly reduced.

[0006]

The latching bolt 6 is housed in a case 2 fixed to a door 1 in the unlocking position restraint type latch device of the present invention, which will be described below with reference to the reference numerals in the accompanying drawings. , The latch bolt 6 is slidably biased by the spring 3 in the direction of engaging with the lock hole 5 on the fixed frame body 4 side, and the lock lever 8 housed in the split groove 7 of the latch bolt 6 is retractable so that the latch bolt 6 can rotate. The lock lever 8 is supported by the spring 3, and the lock lever 8 is rotationally biased by the spring 3 in the direction in which the tip portion is recessed in the split groove 7, and the lock lever 8 is provided with the operation portion 11.
A long keyhole 40 is provided on the front surface of the lock lever 8 along the moving direction of the operating portion 11, and a clearance groove portion 45 is provided on the front surface portion of the operating portion 11 facing the keyhole 40. Is provided with a pair of receiving groove portions 40a, 40b, and a pair of pressing portions 39a, 39b is provided at the tip of the operation protrusion 39 of the key 38.
And the operation projection 3 of the key 38 inserted through the key hole 40.
9 is a pressing portion 39a, 39b of the escape groove 4 of the operating portion 11
When the abdominal surfaces 11a on both sides of 5 are pushed and the latch bolt 6 is slid backward to the unlocked position, the tip surface 8 of the lock lever 8
The a is brought into contact with the hole edge portion 5a of the lock hole 5.

[0007]

When the door 1 is opened, the tip of the latch bolt 6 projects from the case 2, and the tip of the lock lever 8 is housed in the split groove 7 of the latch bolt 6. When the door 1 is rotated in the closing direction in this state, the latch bolt 6 at the terminal end of rotation rotates on the opening edge 4a of the fixed frame 4 or the guide plate fixed to the opening edge 4a on the cam slope 12 at the tip end. Abut When the closing rotation of the door 1 is further continued, the cam slope 1 is opened by the opening edge 4a or the guide plate.
The latch bolt 6 pressed by 2 is temporarily retracted into the case 2 against the bias of the spring 3.

At the moment when the door 1 is rotated to the fully closed position, the latch bolt 6 projects from the case 2 by the sliding force of the spring 3 and engages with the lock hole 5 of the fixed frame body 4 as shown in FIG. To lock the door 1 to the fixed frame body 4. In this locked position, the tip end of the lock lever 8 is kept in the split groove 7 of the latch bolt 6 by the biasing force of the spring 3.

To unlock the door 1, the pressing portions 39a, 39b of the operating projection 39 of the key 38 are positioned in the receiving groove portions 40a, 40b of the key hole 40 of the case 2 and the operating projection 39 is opened.
By inserting the key 38 into the case 2 and pulling the key 38 laterally along the key hole 40.
The abdominal surfaces 11a on both sides of the escape groove portion 45 of the lock lever 8 are pushed by a and 39b. By this pressing operation, the latch bolt 6 is slid backward together with the lock lever 8 against the bias of the spring 3, and the tip end portion of the latch bolt 6 is released from the lock hole 5 of the fixed frame body 4. At the end of the backward operation of the latch bolt 6, the operation portion 11 is pushed down obliquely,
When the lock lever 8 is rotated, the tip of the lock lever 8 projects from the split groove 7 of the latch bolt 6.

When the force applied to the key 38 is weakened while maintaining this protruding state, the latch bolt 6 is slightly advanced by the bias of the spring 3, so that the tip end surface 8a of the lock lever 8 is fixed as shown in FIG. Hole edge portion 5a of the lock hole 5 of the frame body 4
Abut. By this contact, the latch bolt 6 is held at a position where the tip does not re-engage with the lock hole 5, that is, at an unlocked position.

When a plurality of latch devices are used for the door 1, the latch bolts 6 of the respective latch devices are sequentially restrained in this way, and the last latch device is unlocked and the door 1 is opened. This restrained state is secured. When the door 1 is opened, the latch bolt 6 is instantly advanced by the urging force of the spring 3, and the tip portion projects from the case. Further, the lock lever 8 is returned and rotated by the same biasing force of the spring 3, and the tip end thereof is retracted into the split groove 7 of the latch bolt 6.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiment shown in FIGS. 1 to 6, the tip of a latch bolt 6 provided with a cam slope 12 is a box-shaped case 2.
It appears and disappears from the opening 14 of the left side wall 13. The spring 3 used for both the biasing of the sliding of the latch bolt 6 and the biasing of the rotation of the lock lever 8 is composed of a compression coil spring, and one end of the spring 3 has a truncated cone shape on the right side surface of the base end of the lock lever 8. The spring 3 is fitted into the receiving portion 9, and the other end of the spring 3 is fitted into the substantially frustoconical spring receiving portion 10 of the right side wall 16 of the case 2.
The plate-shaped operation portion 11 integrally formed with the lock lever 8 is inserted into the guide slot 18 of the front wall portion 17 of the case 2. A cover 41 is fitted and fixed to the front wall portion 17 of the case 2, and the key hole 40 is provided in the cover 41. The cover 41 may be integrated with the case 2.

A rectangular guide ridge 44 is provided around the key hole 40 of the cover 41, and the plate key-shaped key 38 has
Recesses 4 into which the raised portions 44 enter on both sides of the operation protrusion 39.
3 are formed. The keyhole 40 includes a pair of receiving groove portions 40a,
It is formed in a T shape by 40b. A reinforcing rib 42 is provided on the operation protrusion 39 of the key 38. Operation protrusion 3
9 is formed in a T shape by a pair of pressing portions 39a and 39b. The pressing portions 39a and 39b are the receiving groove portion 40.
When the key 38 is pulled laterally after passing through a and 40b to reach the back side of the cover 41, the key 38 moves along the back side of the cover 41.

On the upper and lower side surfaces of the base end of the lock lever 8,
A shaft portion 21 having a semicircular cross section is provided on an extension of the operation portion 11 so as to project. On the front surface of the middle portion of the latch bolt 6, there is a bearing groove 22 having a U-shaped cross section, which is located in front of the bottom surface 7 a of the receiving groove 7.
Is provided. Since the shaft portion 21 of the lock lever 8 is fitted in the bearing groove 22, the lock lever 8 moves back and forth integrally with the latch bolt 6 and is rotatably supported with respect to the latch bolt 6. .

Stop projections 23 having an arcuate cross-section are provided on the upper and lower side surfaces of the intermediate portion of the operating portion 11, and each stop projection 23 has an inner shoulder portion 25 and a lower surface wall portion 26 of an upper wall portion 24 of the case 2.
By engaging with the inner shoulder 27 of the lock lever 8, the shaft portion 21 of the lock lever 8 is prevented from coming out of the bearing groove 22 of the latch bolt 6.

As shown in FIG. 7, when the tip of the lock lever 8 is recessed in the split groove 7 of the latch bolt 6, the force receiving point of the spring receiving portion 9 on the lock lever 8 side is the spring receiving portion on the case 2 side. Since it is located on the front side with respect to the straight line connecting the force application point of the portion 10 and the center of the shaft portion 21 of the lock lever 8, the spring 3
The rotational urging force due to the elastic force of is exerted in the direction of maintaining the retracted state of the tip portion of the lock lever 8.

As shown in FIG. 6, when the tip of the lock lever 8 projects from the split groove 7 of the latch bolt 6,
The force receiving point of the spring receiving portion 9 on the lock lever 8 side is on a straight line connecting the force receiving point of the spring receiving portion 10 on the case 2 side and the center of the shaft portion 21 of the lock lever 8, or is located on the rear surface side with respect to the straight line. Therefore, the rotational bias by the elastic force of the spring 3 acts in the direction of maintaining the protruding state of the tip portion of the lock lever 8. In this protruding state, the tip of the lock lever 8 is
The case 2 is in contact with the rear surface of the front wall portion 17a that is retracted one step.

That is, the spring 3 functions as a spring of a so-called dead point mechanism, so that the latch bolt 6 is slid in the protruding direction and the lock lever 8 is retracted in response to the movement of the force applied point. Alternatively, it is urged to rotate in the protruding direction. In order to control the posture of the spring 3 and to clarify the movement of the force application point of the spring 3 with respect to the lock lever 8, a ridge 20 is provided in the vertical diametrical direction at the base of the spring receiving portion 9 on the lock lever 8 side. The end of the spring 3 rides on the ridge 20. The spring 3 is inserted into the through hole 37 of the latch bolt 6.

Unlike the present embodiment, even when the tip of the lock lever 8 projects from the split groove 7 of the latch bolt 6, the force receiving point of the spring receiving portion 9 on the lock lever 8 side is the case 2. Side of the spring receiving portion 10 and the lock lever 8
When it is set so as to be on the front side with respect to the straight line connecting the centers of the shaft portions 21, the rotational bias by the elastic force of the spring 3 acts in the direction in which the tip portion of the lock lever 8 is sunk. However, even in this case, the front end surface 8a of the lock lever 8 is engaged with the hole edge portion 5a of the fixed frame body 5,
The lock lever 8 does not rotate in the retracted direction because it is obstructed by the hole edge portion 5a.

When the latch bolt 6 advances to the locked position,
The operating portion 11 of the lock lever 8 that has been integrally advanced abuts on the left inner wall surface 18a of the guide slot 18 on the left side surface 11a, and the stopper shoulder 19 on the tip side of the latch bolt 6 is connected to the left side wall portion 13 of the case 2. Abut. When the latch bolt 6 is retracted to the unlocked position, the right side surface 1 of the operation unit 11
1b contacts the right inner wall surface 18b of the guide slot 18.

In each of the above embodiments, the case has an upper half 2a.
The lower half 2b is plastically molded in half, and the upper half 2a and the lower half 2b are connected by the connecting strip plate portion 15 on the back surface. On one joining end surface of the upper half 2a and the lower half 2b, a joining recess 28 is provided at a position farthest from the connecting strip plate portion 15.
Is formed, and a bonding projection 29 is formed at the same position on the other side. The upper half a and the lower half 2b, which are folded and closed by the connecting strip plate portion 15, have the joining concave portion 28.
It is held in a closed state by the engagement of the projection 29 with the projection 29.

The spring receiving portion 10 on the case 2 side is also divided into two parts, and when closed for the above, the upper half 2a.
Side spring receiving portion 10a and lower half 2b side spring receiving portion 10b are closed in a substantially circular cross-section, and the ends of the compression coil spring 3 are fitted therein, so that the upper half 2a and the lower half 2 of the case 2 are fitted together.
b is prevented from separating. Guide grooves 30 are formed on the upper and lower side surfaces of the latch bolt 6, and guide ribs 31 that engage with the guide grooves 30 are provided in the left and right directions on the upper surface wall portion 24 and the lower surface wall portion 26 of the case 2.

A mounting plate portion 32, which is inclined upward toward the front surface, is provided at an intermediate portion between the upper surface wall portion 24 and the lower surface wall portion 26 of the case 2.
And the mounting plate portion 33 is cut and raised, and each mounting plate portion 32,
Stepped locking protrusions 34 and 35 are provided at the tip of 33. When the case 2 is inserted into the receiving hole 36 of the door 1 from the front side, the upper and lower mounting plate portions 32 and 33 are slightly elastically deformed inward around the root portion on the rear end side, and the front wall portion of the case 2 is formed. 1
When 7 comes into contact with the front surface of the door 1, the mounting plate portions 32 and 33 are elastically restored, and the locking protrusions 34 and 35 at the tip end engage with the rear surface of the door 1 to prevent the case 2 from coming off. .

[0024]

As described above, in the latch device of the present invention,
The lock lever 8 housed in the split groove 7 of the latch bolt 6 is rotatably supported by the latch bolt 6, and the lock lever 8 is rotated by the spring 3 in a direction in which the tip end of the lock lever 8 is retracted or projected from the split groove 7. When the latch bolt 6 is biased and the operating portion 11 is provided, and the latch bolt 6 is slid back to the unlocked position, the tip end surface 8a of the lock lever 8 protruding from the split groove 7 is moved to the edge of the lock hole 5. Since it abuts against the portion 5a, the latch bolt 6 can be accurately restrained at the unlocked position, and even when a plurality of latch devices are used in parallel, the unlocking / opening operation of the door can be easily performed by one person. Since the sliding biasing spring of the latch bolt 6 and the rotation biasing spring of the lock lever 8 are composed of a single spring, the internal structure is simplified, and the manufacturing and assembling can be performed easily and inexpensively.

Further, in the latch device of the present invention, the case 2
A long keyhole 40 is provided on the front surface of the lock lever 8 along the moving direction of the operating portion 11, and a clearance groove portion 45 is provided on the front surface portion of the operating portion 11 facing the keyhole 40. Is provided with a pair of receiving groove portions 40a, 40b, and a pair of pressing portions 39a, 39b is provided at the tip of the operation protrusion 39 of the key 38.
Is provided, and the pressing portions 39a, 39 are attached to the receiving groove portions 40a, 40b.
b is positioned and the key 38 is inserted into the key hole 40, and the key 38 is pulled sideways so that the pressing portions 39a and 39b of the operating projection 39 are used to press the abdominal surfaces 1 on both sides of the escape groove portion 45 of the operating portion 11 of the lock lever 8.
1a is pushed so that the latch bolt 6 can be slid backward to the unlocked position. Even if a driver or a rod can be inserted into the key hole 40 and pulled laterally, the driver or rod can be pulled. The tip of the material is the escape groove 45 of the operation unit 11.
There is no risk that an unauthorized person who does not own the legitimate key 38 will operate the lock lever without permission and the latch device will be unlocked improperly.

[Brief description of drawings]

FIG. 1 is a bottom view of an unlocking position restraint type latch device according to an embodiment of the present invention in a locked state, in which a key is in a state just before insertion.

FIG. 2 is a left side view of the latch device in which the key is inserted in the case.

FIG. 3 is a front view of the latch device in which a key is removed from the case.

FIG. 4 is a front view of a key used in the latch device.

FIG. 5 is a horizontal sectional view when the latch bottle of the latch device is in the locked position, with the key in the inserted state.

FIG. 6 is a cross-sectional view showing a state in which a latch bolt of the latch device is restrained in an unlocked position.

[Explanation of symbols]

 1 Door 2 Case 3 Spring for Energizing Latch Bolt and Lock Lever 4 Fixed Frame Body 5 Lock Hole on Fixed Frame Body 5a Hole Edge of Lock Hole on Fixed Frame Body 5b Inner Wall Surface of Lock Hole on Fixed Frame Body 6 Latch Bolt 7 Latch bolt split groove 8 Lock lever 8a Lock lever tip surface 9 Lock lever side spring receiving part 10 Case side spring receiving part 11 Lock lever operating part 11a Operating part abdominal surface 12 Latch bolt cam slope 13 Case Left side wall 14 Case opening 15 Connection strip 16 Right side wall 17 Case front wall 18 Guide slot 19 Stopper shoulder 20 Projection 21 Lock lever shaft 22 Latch bolt bearing groove 23 Lock lever Stop projection 24 Case upper surface wall 25 Case upper surface wall side inner shoulder 26 Case lower surface wall 27 Case lower surface Inner surface shoulder part on the wall side 28 Joining concave part 29 Joining convex part 30 Guide groove 31 Guide protrusion 32 Case upper surface side mounting plate part 33 Case lower surface side mounting plate part 34 Case upper surface side locking projection 35 Case lower surface side locking Protrusion 36 Door receiving hole 37 Latch bolt through hole 38 Key 39 Key operating protrusion 39a Operating protrusion pressing portion 39b Operating protrusion pressing portion 40 Case side key hole 40a Key hole receiving groove 40b Key hole receiving Groove portion 41 Cover 42 Reinforcing rib for key operation protrusion 45 Relief groove portion of lock lever operation portion

Claims (1)

[Claims] 1. A latch bolt 6 is housed in a case 2 fixed to a door 1, and the latch bolt 6 is slidably urged by a spring 3 in a direction to engage with a lock hole 5 on a side of a fixed frame 4 to latch. The lock lever 8 housed in the split groove 7 of the bolt 6 is rotatably supported by the latch bolt 6, and the lock lever 8 is rotationally urged by the spring 3 in the direction in which the tip end is inserted into the split groove 7. 8 is provided with an operating portion 11, a long keyhole 40 is provided on the front surface of the case 2 along the moving direction of the operating portion 11 of the lock lever 8, and a clearance groove portion is provided on the front surface of the operating portion 11 facing the keyhole 40. 45, a pair of receiving groove portions 40a and 40b are provided at the front end of the key hole 40, and the key 38
Of the pair of pressing parts 39a, 39
b is provided, and the pressing portions 39a and 39b of the operation protrusion 39 of the key 38 inserted through the key hole 40 push the abdominal surfaces 11a on both sides of the escape groove portion 45 of the operation portion 11 to slide the latch bolt 6 backward to the unlocked position. An unlocking position restraint type latch device in which, when moved, the tip end surface 8a of the lock lever 8 is brought into contact with the hole edge portion 5a of the lock hole 5.