JPH0540114Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention relates to a locking device for a manhole.

[Conventional technology]

2. Description of the Related Art Conventionally, for security reasons, there is a manhole locking device shown in FIG. 6 for preventing the iron cover of a manhole from being opened without authorization. That is, this manhole locking device includes a bolt 23 vertically inserted into the end of the iron cover 1, a locking metal fitting 24 horizontally fixed to the lower end of the bolt 23, and a projection protruding from the inner surface of the receiving frame 17. It consists of 18.

According to the conventional locking device described above, after fitting the iron lid 1 into the receiving frame 4, the iron lid 1 is locked by turning the bolt 23 and positioning the locking fitting 24 on the lower surface of the protrusion 18. can, and
By further turning the bolt 23 and removing the locking fitting 24 from the protrusion 5, the iron lid 1 can be opened.

[Problem that the invention attempts to solve]

However, the conventional locking device described above has the following problems. That is, the locking fitting 24 is easily dislodged from the protrusion 18 due to vibrations from a vehicle, etc., and the bolt 23 can be easily turned using an existing tool, which is not desirable in terms of safety.

[Purpose of invention]

Therefore, the object of this invention is to provide a manhole locking device that can prevent the lock from being unlocked due to vibrations from vehicles or existing tools.

[Means for solving problems]

This device includes a first lock provided on the bottom surface of the iron lid, a second lock provided on the bottom surface of the iron lid at a distance from the first lock, and a mechanism for unlocking the first lock. The first lock has a key hole perpendicular to the axis, a first insertion hole for the first lock pin on the side, and a second insertion hole for the second lock pin on the bottom. a first cylinder for preventing rotation of the first cylinder, the first cylinder being inserted horizontally into the first insertion hole of the first cylinder;
a lock pin, a spring for applying a pressing force to the first lock pin in the direction of the first insertion hole, and a suction force on the first lock pin against the elasticity of the spring to pull it into the first insertion hole. The second lock includes a second cylinder having a keyhole perpendicular to the axis, one end of which engages with a side of the second cylinder, and the other end of which engages with the side of the second cylinder.
a second lock pin inserted into the second insertion hole of the lock, the one end of which engages with a protrusion formed inside a receiving frame for receiving the iron lid; and the release means is inserted into the second insertion hole of the lock. The present invention is characterized in that it includes a control circuit for operating the electromagnet.

Next, one embodiment of the manhole locking device of this invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the manhole locking device of this invention, and FIG.
3 is a sectional view taken along line B-B in FIG. 1.

As shown in FIGS. 1 to 3, the manhole locking device of this invention has a first lock 2 provided on the bottom surface of the iron cover 1, and a first lock 2 provided on the bottom surface of the iron cover 1 with a space between the first lock 2 and the first lock 2 provided on the bottom surface of the iron cover 1. It consists of a second lock 3 and a release means 4 for unlocking the first lock 2.

The first lock 2 consists of a first cylinder 5, a first lock pin 6, a spring 7, and an electromagnet 8. The first cylinder 5 has a keyhole 9 perpendicular to its axis, a first insertion hole 10 on the side into which the first lock pin 6 is inserted, and the other end of a second lock pin (described later) on the bottom. It has a second insertion hole 11 into which it is inserted. The first lock pin 6 is inserted into the first insertion hole 10 of the first cylinder 5 by the elastic force of the spring 7 when the iron lid is locked. By this, the first lock 2
is locked. The electromagnet 7 is connected to the first lock pin 6
is sucked against the elasticity of the spring 7 and pulled out from the first insertion hole 10. As a result, the first lock 2 is unlocked.

The second lock 3 consists of a second cylinder 12 and a second lock pin 13. 2nd cylinder 1
2 has a keyhole 14 perpendicular to the shaft center, and a pinion 15 on the side that engages with a rack to be described later. The second lock pin 13 has a pinion 15 at one end.
It has a rack 16 that engages with the. The second lock pin 13 moves in the horizontal direction as the second cylinder 12 rotates, and one end thereof is connected to the receiving frame 17 of the iron lid 1.
The iron lid 1 is locked by engaging with the protrusion 18 formed inside the cylinder, and the iron lid 1 is locked by the other end entering the second insertion hole 11 of the first cylinder 5. It will be canceled.

The release means 4 is a switch box 1 having a plug 24 that can be freely inserted into a socket 23 of the iron lid 1.
9 and a control circuit 20. The switchbox 19 sends electrical signals from each switch to a control circuit 20, and the control circuit 20 causes the electromagnet 8 of the first key 2 to receive current by the electrical signals from the switches in a predetermined combination. energize.

[Effect]

According to the above-mentioned manhole locking device of this invention, the iron cover is locked and unlocked in the following manner.

Fit the plug 24 of the switchbox 19 into the socket 23 of the iron lid 1, and then
When specific switches are pressed in a predetermined sequence, a current is passed through the control circuit 20 to the electromagnet 8 of the first lock 2. As a result, the first lock pin 6 is attracted against the elastic force of the spring 7. As a result, the first lock pin 6 comes out of the first insertion hole 10 of the first cylinder 5, and the first lock 2 is unlocked. Next, insert the key 21 shown in FIG. let next,
In the keyhole 14 of the second cylinder 12 of the second lock 3,
Insert the key 22 shown in FIG. 5 and turn the second cylinder 12 clockwise. 2nd lock pin 6
Since the other end is inserted into the second insertion hole 11 of the first cylinder 5, one end of the second lock pin 6 is disengaged from the protrusion 18 of the receiving frame 17, and the second lock 3
is unlocked. As a result, the iron lid 1 is unlocked.

To lock the iron lid 1, after fitting the iron lid 1 into the receiving frame 17, the second cylinder 12 is turned counterclockwise to engage one end of the second lock pin 13 with the protrusion 18 of the receiving frame 17. Next, the first cylinder 5
The first lock pin 6 is inserted into the first insertion hole 10 of the first cylinder 5 by the elastic force of the spring 7. This prevents the first cylinder 5 from rotating, so the first lock 2 is locked. Since the other end of the second lock pin 13 and the second insertion hole 11 of the first cylinder 5 do not face each other, rotation of the second cylinder 12 is also prevented, and the second lock pin 13 is prevented from rotating.
Simultaneously with locking of lock 2, second lock 3 is locked. As a result, the iron lid 1 is completely locked.

[Effect of idea]

As explained above, according to this invention, the iron lid cannot be opened unless a specific switch is pressed using a switch box, and furthermore, the lock may be unlocked due to vibrations from the car, etc. It has very useful effects such as:

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of the manhole locking device of this invention, and FIG.
3 is a sectional view taken along line B-B in FIG. 1, FIGS. 4 and 5 are a front view of the key, and FIG.
The figure is a sectional view of a conventional manhole locking device. In the drawings, 1... iron lid, 2... first lock, 3... second lock, 4... release means, 5... first cylinder, 6
...First lock pin, 7...Spring, 8...Electromagnet, 9...Keyhole, 10...First insertion hole, 11...
Second insertion hole, 12... Second cylinder, 13...
2nd lock pin, 14...Keyhole, 15...Pinion, 16...Rack, 17...Reception frame, 18...Protrusion, 19...Switchbox, 20...Control circuit, 21...Key, 22... Key.

Claims (1)

[Scope of utility model registration request] a first lock provided on the lower surface of the iron lid; a second lock provided on the lower surface of the iron lid at a distance from the first lock; and a release means for unlocking the first lock. The first lock has a key hole perpendicular to the axis, a first insertion hole for the first lock pin in the side part, and a second insertion hole for the second lock pin in the bottom part. a cylinder, a first lock pin for preventing rotation of the first cylinder that is inserted horizontally into the first insertion hole of the first cylinder, and a pressing force applied to the first lock pin in the direction of the first insertion hole. The second lock includes a spring for attaching the lock pin, and an electromagnet for sucking the first lock pin against the elasticity of the spring and extracting it from the first insertion hole. a second cylinder having a vertical keyhole; one end engaged with a side of the second cylinder; the other end inserted into the second insertion hole of the first lock; a second lock pin that engages with a protrusion formed inside a receiving frame for receiving the lock, and the release means includes a control circuit for activating the electromagnet of the first lock. Locking device for manhole.