JPH0325809Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention is a smoke screen lifting/lowering operating device that can control the descending speed of the smoke screen by using a motor for winding up the smoke screen. It is related to.

[Prior art and problems to be solved by the invention] In general, smoke screens are hung from the ceiling in order to prevent smoke damage by suppressing the spread of smoke generated in emergency situations such as fire. It is used for Conventionally, most smoke screens have been lowered under their own weight in the event of an emergency such as a fire, and raised by manually operating an opening/closing machine. When such manual operation is carried out using a transmission means using a wire cable, as the distance between the switch and the operating section increases, the frictional resistance of the wire cable increases and a large operating force is required, resulting in extremely poor operability. Moreover, as mentioned above, the descent of the smoke screen is due to the descent of the seat plate and screen cloth by their own weight due to the release of the brake, so if the descent speed becomes too fast, the adjacent smoke screen will not fit properly, and from here Smoke could leak out, and to prevent this, a special descending speed regulator had to be installed separately, increasing equipment costs. Therefore, it may be possible to raise and lower the smoke screen using an electric motor, but in this case,
This could not be adopted because power outages often occur during emergencies such as fires.

[Means for Solving the Problem] In view of the above-mentioned circumstances, the present invention has been devised for the purpose of providing a device for lifting and lowering a smoke screen that can eliminate these drawbacks. The opening/closing machine is equipped with a DC motor for winding up the screen, and the motor and a detector that detects an emergency situation are linked so that it is released by an emergency detection command, and the power supply circuit of the motor is connected to a smoke-proof It is configured to be switchable so that it becomes a closed circuit with a resistor except when the screen is being hoisted up, and the lowering speed is controlled by the back electromotive force generated by the forced rotation of the motor as the smoke screen lowers. It is characterized by the fact that

With this configuration, the present invention enables the smoke screen to descend reliably with a controlled descending speed even if an electric motor is used, thereby eliminating the spread of smoke. This is what I did to get it.

[Example] Next, an example of the present invention will be described based on the drawings. In the drawing, 1 is a smoke screen, 2 is a shaft that winds up the smoke screen 1, 3 is a switch that drives the shaft 2, and DM is a DC motor connected to the switch 3. Then, the motor DM is started by closing the push button switch PBU and the switch 3 is activated.
rotates, sprocket 7a, 7b, chain 7c
Rotation is transmitted to the shaft 2 via a transmission mechanism 7 consisting of the following, and the smoke screen 1 is rolled up. On the other hand, 5 is a smoke detector installed on the ceiling 6, etc., and 5a is its starting contact. When the smoke detector 5 detects smoke, the starting contact 5a starts and closes and sends a detection signal to the interlocking controller 4. , the brake release solenoid SOL installed on the motor DM is activated. Further, Ry is a relay provided in the DC power supply (E) circuit, and the relay contacts of this relay Ry are provided in the circuit that self-maintains the closing of the push button switch PBU and the power supply circuit of the motor DM. However, on the power supply circuit side, the motor DM is a closed contact on the side forming a closed circuit with the variable resistor R. And push button switch PBU
When closed, this relay contact switches and direct current flows to the motor DM.

In the embodiment of the present invention configured as described above, for example, if a fire breaks out in a building and the smoke detector 5 installed on the ceiling 6 detects smoke, the starting contact 5a closes and performs interlock control. Send a signal to device 4. In response to this, the interlock controller 4 operates the solenoid.
Activate SOL and release the brake of DC motor DM. Since the brake has been released, the smoke screen 1 begins to descend under its own weight. At this time, the shaft 2 rotates due to the lowering of the smoke screen 1, and the direct current motor DM is reversely rotated through the transmission mechanism 7 and the switchgear 3. In this state, as described above, the DC motor DM forms a closed circuit with the variable resistor R, so as the electric motor DM reverses as the smoke screen 1 descends, the closed circuit is induced by the back electromotive force. A current will be generated. As a result, a rotational resistance commensurate with the resistance capacity of the variable resistor R is generated in the electric motor DM, and this acts as a brake on the descending speed of the smoke screen, which is lowered by its own weight. The smoke screen 1 will be lowered at a controlled and appropriate speed, and the smoke screen 1 will not be disturbed. Furthermore, the smoke screen 1 can be lowered without any problem even in the event of a power outage. Furthermore, since the smoke screen 1 can be raised automatically by pressing the push button switch PBU, there is no need to perform the complicated and troublesome work that was conventionally done manually.

Note that by varying the resistance value in accordance with the size of the smoke screen 1, the descending speed can be adjusted regardless of the size of the screen.

[Operations and Effects] In summary, since the present invention is constructed as described above, the lowered smoke screen can be hoisted up extremely easily by motor drive without the need for complicated and troublesome operations. However, in the event of an emergency such as a fire, the speed at which the smoke screen falls due to its own weight when the brake is released can be controlled by effectively utilizing the back electromotive force caused by the reversal of the screen winding motor. There is no need to provide a special speed governor,
Therefore, the smoke prevention screen can be lowered in an orderly manner without any disturbance, and extremely high smoke prevention performance can be exhibited.

[Brief explanation of drawings]

The drawing shows one embodiment of the DC electric operating device for a smoke-proof screen according to the present invention.
The figure is a front view of the smoke screen, and Figures 2 and 3 are circuit diagrams. In the diagram, 1 is the smoke screen, 2 is the shaft, and 3
is a switch, 4 is an interlocking controller, 5 is a smoke detector, 5a
is the starting contact, 6 is the ceiling, 7 is the transmission mechanism, 7a, 7
b is sprocket, 7c is chain, E is DC power supply, DM is DC motor, SOL is solenoid,
PBU is a push button switch, LSU is an upper limit switch, R is a variable resistor, and Ry is a relay.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A smoke screen opening/closing machine is provided with a DC motor for winding up the screen, and the motor and a detector for detecting an emergency situation are activated by a command to detect an emergency situation. In addition, the motor's power supply circuit is set to be switchable so that it becomes a closed circuit with a resistor except when the smoke screen is being rolled up, so that the motor is forced to rotate as the smoke screen is lowered. A device for lifting and lowering a smoke screen, characterized in that the device is configured to control the descending speed using a counter electromotive force. (2) The smoke screen lifting/lowering operating device according to claim 1, wherein the resistor is a variable resistor.