JP2751040B2 - Locking device for manhole cover - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lock device used for a manhole cover at an entrance to an underground common groove in which a communication cable or the like is accommodated.

[0002]

2. Description of the Related Art A conventional lock device for a manhole cover disclosed in Japanese Utility Model Publication No. 6-330003 is provided with a housing embedded and fixed in a manhole cover; A guide cylinder; a latch rod fitted into a horizontal slot of the housing and engaged with a receiving portion on the manhole frame side; a driving plate connected to an outer cylinder rotatably inserted into the guide cylinder by a horizontal pivot, and When the inner cylinder inserted into the cylinder is pushed down, the drive plate rotates and consists of a cylindrical key protruding from the vertical groove on the side wall of the tip of the outer cylinder. And the driving plate pushes the wall surface of the passive notch to slide the latch bar forward and backward.

However, in this conventional apparatus, when the cylindrical key is inserted into the guide cylinder to a predetermined depth, the side wall at the distal end of the outer cylinder is designed to be exposed from the lower end opening of the guide cylinder. As a result, the driving plate immediately projects and rotates into the open space between the latch rod and the guide cylinder.

[0004] Therefore, if there is a foreign matter or an interfering object such as a residual device in the space, the protruding rotation of the driving plate itself is prevented, or even if the protruding rotation is not prevented, the driving plate comes into contact with the interfering object and the latch rod is moved. If the drive plate or the outer cylinder is distorted or broken when a large rotational force is applied to the cylindrical key with a lever lever with a large lever ratio while the drive plate is in contact with the interference object, the drive plate or outer cylinder may not be pressed. It will lead to an accident.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a lock device for a manhole cover in which a driving plate does not protrude and rotate into an external open space, so that operation or failure due to foreign matter or interference is not caused. It is to be.

[0006]

A manhole cover locking device according to the present invention comprises: a main shaft 4 rotatably fitted into a vertical shaft hole 3 of a housing 2; a main shaft 4 fitted into a horizontal slot 5 of the housing 2; A latch rod 8 which slides forward and backward in conjunction with the rotation to engage and disengage with a receiving portion 7 on the manhole frame 6 side; a driving plate 15 on an outer cylinder 14 rotatably inserted into a vertical keyhole 9 of the main shaft 4;
Are connected by a horizontal pivot 16 and the inner cylinder 1 inserted into the outer cylinder 14.
When the key 7 is depressed, the drive plate 15 is rotated to form the cylindrical key 10 protruding from the vertical groove 18 on the side wall of the distal end of the outer cylinder 14.
The inner wall surface 19 of the vertical keyhole 9 surrounds the distal end side wall of the outer cylinder 14 over the entire circumference, and the inner wall surface 19 is provided with a passive groove 20 with which the drive plate 15 engages and disengages.

The manhole cover 6 is formed by the manhole cover 1.
After the entrance 21 is closed, the cylindrical key 10 is inserted into the vertical keyhole 9 of the main shaft 4 at an arbitrary position as shown in FIG.
The inner cylinder 17 is pushed down along the outer cylinder 14. When the inner cylinder 17 is pressed down, the driving plate 15 is urged to protrude and rotate about the horizontal pivot 16, and as shown in FIG.
5 has a vertical keyhole 9 in a vertical groove 18 of the outer cylinder 14.
Abuts on the inner wall surface 19. When the cylindrical key 10 is turned while the inner cylinder 17 is pushed down, the tip of the drive plate 15 slides on the inner wall surface 19 in the circumferential direction.

As shown in FIG. 7, when the cylindrical key 10 is rotated to the normal position and the vertical groove 18 of the outer cylinder 14 faces the passive groove 20 of the inner wall surface 19, the distal end of the driving plate 15 is As shown in FIG. When the cylindrical key 10 is rotated while being pressed, the driving plate 15 presses one wall surface 22 of the passive groove 20, so that the main shaft 4 is rotated in the locking direction, and the latch rod 8 interlocked with the main shaft 4 slides forward. Then, it engages with the receiving portion 7 of the manhole frame 6. After locking the manhole cover 1 to the manhole frame 6 in this manner,
When the depression of the inner cylinder 17 is released, the distal end of the drive plate 15 escapes from the passive groove 20 of the main shaft 4 and the vertical groove 18 of the outer cylinder 14.
The cylindrical key 10 is withdrawn from the vertical keyhole 9 of the main shaft 4 without any trouble.

When it is desired to open the manhole cover 1 for maintenance of a common groove or a communication cable, the cylindrical key 10 is inserted into the vertical keyhole 9 of the main shaft 4 to a predetermined depth and the inner cylinder 17 is opened as in the case of locking. Press down. The drive plate 15 urged to rotate about the horizontal pivot 16 has a tip portion formed in the longitudinal groove 1 of the outer cylinder 14.
8, it contacts the inner wall surface 19 of the vertical keyhole 9. When the cylindrical key 10 is turned while the inner cylinder 17 is pressed down, the drive plate 15
Is in sliding contact with the inner wall surface 19 in the circumferential direction.

When the cylindrical key 10 rotates to the normal position, the outer cylinder 1
When the fourth vertical groove 18 faces the passive groove 20 on the inner wall surface 19, the tip of the driving plate 15 enters the passive groove 20. When the cylindrical key 10 is rotated while being depressed, the driving plate 15 presses the other wall surface 23 of the passive groove 20, so that the main shaft 4 is rotated in the unlocking direction, and the latch rod 8 is slid backward to slide the manhole. The frame 6 is separated from the receiving portion 7. After unlocking the manhole cover 1 with respect to the manhole frame 6 in this manner, when the depression of the inner cylinder 17 is released, the tip of the drive plate 15 escapes from the passive groove 20 of the main shaft 4 and the outer cylinder 14 The cylindrical key 10 is withdrawn from the vertical keyhole 9 of the main shaft 4 to be retracted inside the outer peripheral surface, that is, into the vertical groove 18.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the illustrated embodiment, a female screw is cut in an upper part of a vertical shaft hole 3 of a housing 2 and a blind plug 11 is screwed therein. The enlarged head of the blind plug 11 is provided with a triangular rotary operation recess 12. Blind plug 11
Is removed prior to insertion of the tubular key 10. Housing 2
Is integrally formed with the manhole cover 1 or formed separately and fixed to the manhole cover 1. The back plate 13 forming the lower wall surface of the horizontal slot 5 of the housing 2 is fixed to the housing body by four bolts 24, and one end of the back plate 13 supports a lower end cylindrical portion 25 of the main shaft 4. A hole 26 is provided. The cylindrical portion 25 at the lower end of the main shaft 4 is inserted into an elongated escape hole 27 at an intermediate portion of the latch rod 8.

Lower surface blind hole 29 of intermediate circular flange 28 of main shaft 4
An interlocking pin 30 is driven into and fixed to, and an interlocking pin 32 is swaged and fixed into the through hole 31 at the base end of the latch rod 8. These link pins 30 and 32 are linked link 3
3 are fitted in receiving holes 34 and 35 at both ends of the main shaft 4.
The latch rod 8 is guided by the horizontal slot 5 and slides forward and backward in conjunction with the rotation of. The passive groove 20 of the main shaft 4 is provided in the upper end cylindrical portion 36 of the main shaft 4 vertically long.

The upper end of the outer cylinder 14 of the cylindrical key 10 is provided with a stop flange 37 for specifying the insertion depth.
The vertical groove 18 provided at the lower end of 4 is formed in the shape of a split groove in the diameter direction. The knob 39 fitted into the split groove 38 at the upper end of the inner cylinder 17 is fixed to the inner cylinder 17 by a transverse pin 40. A guide pin 42 diametrically penetrating the outer cylinder 14 is fitted into a vertical hole 41 at an intermediate portion of the inner cylinder 17.
The inner cylinder 17 is urged to slide upward by a compression coil spring 43 inserted between the upper inner bottom surface 17a of 7 and the guide pin 42. The horizontal pivot 16 is also inserted through the vertical hole 41.

The upper end of the drive plate 15 enters the inside of the inner cylinder 17, and the lower end of the inner cylinder 17 is provided with an operation projection 45 that abuts on the cam slope 44 in the middle of the drive plate 15. When the inner cylinder 17 is pushed down by the knob 39, the operation projection 45 of the inner cylinder 17 pushes the cam slope 44 of the drive plate 15, so that the drive plate 15 rotates about the horizontal pivot 16, and the tip of the drive plate 15 It enters the passive groove 20 of the main shaft 4. The driving plate 15 is dimensioned so that the tip does not protrude toward the outer surface of the passive groove 20.

The return biasing spring 46 of the driving plate 15 is constituted by a torsion coil spring in which a coil portion is fitted on the horizontal shaft 16, and one straight end 47 of the spring 46 abuts on the inner surface of the inner cylinder 17, and the other end. Is in contact with the side surface of the drive plate 15, whereby the drive plate 15 is constantly urged to rotate in the retreating direction.

[0016]

As described above, in the lock device for a manhole cover according to the first aspect of the present invention, the inner wall surface 19 of the vertical keyhole 9 of the housing 2 completely surrounds the distal end side wall of the outer cylinder 14 of the cylindrical key 10. Since the passive groove 20 is provided on the inner wall surface 19 so that the front end of the drive plate 15
5 does not protrude and rotate into an external open space, does not cause operation failure or failure due to foreign matter or interference, and is excellent in operation reliability and durability.

In the lock device for a manhole cover according to the second aspect, when the depression by the inner cylinder 17 is released, the driving portion 15 is driven such that the tip end portion of the drive plate 15 returns to a position retracted inward from the outer peripheral surface of the outer cylinder 14. Since the plate 15 is rotationally urged by the spring 46, the operation of inserting and removing the cylindrical key 10 can be performed smoothly and quickly without being affected by the posture position.

[Brief description of the drawings]

FIG. 1 is a plan view showing a locked state of a lock device for a manhole cover according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is a sectional view taken along line CC of FIG. 2;

5 is a cross-sectional view corresponding to FIG. 3, showing a state where a cylindrical key is inserted at an arbitrary position into a main shaft of the lock device.

FIG. 6 is a sectional view taken along line DD of FIG. 5;

FIG. 7 is a cross-sectional view corresponding to FIG. 3, showing a state where the tubular key is rotated to a normal position and the drive plate is engaged with the passive groove of the main shaft.

FIG. 8 is a sectional view taken along line EE of FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Manhole cover 2 Housing 3 Vertical shaft hole of housing 4 Main shaft 5 Horizontal slot of housing 6 Manhole frame 7 Receiving part on manhole frame side 8 Latch bar 9 Vertical keyhole of main shaft 10 Cylindrical key 13 Back plate of housing 14 Tube Outer cylinder of mold key 15 Driving plate of cylinder key 16 Horizontal pivot 17 Inner cylinder of cylinder key 18 Vertical groove of outer cylinder 19 Inner wall surface of vertical keyhole 20 Passive groove on main shaft side

Claims (2)

(57) [Claims] 1. A main shaft 4 rotatably fitted in a vertical shaft hole 3 of a housing 2; a main shaft frame fitted in a horizontal groove 5 of the housing 2 to advance and retreat in conjunction with the rotation of the main shaft 4; A latch rod 8 which is engaged with and disengaged from a receiving part 7 on the side 6;
The drive plate 15 is connected to the outer cylinder 14 rotatably inserted into the vertical keyhole 9 by a horizontal pivot 16. When the inner cylinder 17 inserted into the outer cylinder 14 is pressed down, the drive plate 15 rotates to rotate the outer cylinder 14. A cylindrical key 10 protruding from a vertical groove 18 in the distal end side wall, a passive groove in which the inner wall surface 19 of the vertical keyhole 9 surrounds the entire distal end side wall of the outer cylinder 14 and the driving plate 15 is engaged and disengaged. 20 is provided on the inner wall surface 19, and the passive groove 2 is
A lock device for a manhole cover that pushes the wall surface of the main shaft 4 to rotate the main shaft 4. 2. When the pressing down by the inner cylinder 17 is released, the driving plate 15 is rotationally urged by the spring 46 so that the distal end of the driving plate 15 returns to a position retracted inside the outer peripheral surface of the outer cylinder 14. The lock device for a manhole cover according to claim 1, wherein