JPS6074204A - Motor-driven elevator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD OF THE INVENTION The present invention relates to a lift-up rack in which a motor is used to raise and lower instruments suspended from a rack.

Technical R view and its problems Traditionally, for example, in buildings with high ceilings such as gymnasiums, the light fixtures were raised and lowered by attaching the light fixtures to the ends of the 8-piece rack and rotating the shaft around the motor drum. I'm trying to make it possible. The motor drum is driven by operating a changeover switch attached to a wall or the like. For example, 1'f, in Japanese Utility Model Publication No. 47-8069, a technology is shown in which a lamp is raised and lowered by rotating a drum around which a wire is wound. When the lowering operation is completely stopped, the rotation of the drum is stopped by one step to prevent further unraveling of the wire. This prevents the lamp from falling suddenly when it is removed. however,
At this time, the motor operates again, and the lamp descends at a predetermined speed. Therefore, the lower position tit and the higher position are fixedly determined.

OBJECTS OF THE INVENTION The object of the present invention is to provide an electric lifting and lowering device capable of keeping the device stationary at that position when the device is stopped while it is being lowered.

SUMMARY OF THE INVENTION The present invention provides a mechanism for lowering an instrument by rotating a motor drum in the downward direction, and when the descending of the instrument is stopped at a desired position, the rake becomes slack, and a slack detection switch detects this. By energizing the relay, the descending circuit of the shimotor is cut off, and the relay is self-holding, so the device remains stationary at that position after that, and there is no need to hold the device down. It is designed so that the necessary work can be done easily since there is no need for it.

Embodiments of the Invention First, an example in which the invention is applied to a lighting equipment will be shown.A motor drum (3) connected to and driven by a motor (2) is attached to the ceiling surface (II). A strip (4) of wire or the like is wound around the strip (4).This strip (4) is wound around a pulley (5) and suspended downward, and a lamp (6) as a fixture is attached to the end of the strip (4). ) is attached.A bracket (7) is attached that holds this lamp (6) and also makes electrical connection through contacts (not shown).
) is provided at the top of the bracket (7), and a normally closed upper limit switch (
A control plate (9) is provided for opening 8).

Further, between the motor drum (3) and the pulley (5) is a tensioning part u01 in which the wedge (4) is stretched under the weight of the lamp t61. Part (1
The swing arm Uυ that comes into contact with 6<east+4) of 0) is biased counterclockwise by a spring U, and the slack of the pile (4) is detected through this swing arm U. A normally closed slack detection switch is provided.

Next, a changeover switch Uω (not shown) mounted on a wall (not shown) is connected to the power supply, and this changeover switch U9 valves the ascending circuit U and the descending circuit U7) to switch the motor (2).
It is connected to the. The upper limit switch (8) exists in the upper row circuit ub+.

Further, the motor (2) is located on the lowering circuit Un side.
The slack detection switch u31 and +)V-ul are connected in parallel with
A series circuit with IJ V-coil four is connected.

The phosphor has a normally open self-holding state 4 and a normally closed relay contact (2υ), the self-holding contact (4) is connected in parallel with the slack detection switch (13i), and the relay contact switch υ is connected in parallel with the slack detection switch (13i). It is inserted into the lowering circuit (I'r).

In such a configuration, when the changeover switch 9 located on the wall is operated to switch to the ascending circuit U61 or the descending circuit U7J, the motor (2) rotates forward or reverse and rotates the motor drum (3) in either direction. This allows the lamp (
6) Raise or lower. When attempting to replace the lamp, turn the selector switch down to the lower circuit +1.
7] There are buds on the side. In response to this, the motor drum (3) is rotated counterclockwise to produce a pile +41 t: solution, and the lamp (6) is completely lowered at a constant speed. In this state, the worker moves to the bottom of the lamp (6), waits for the lamp (6) to come down, and stops holding the lamp (6) when the height of the workpiece is suitable for work. As a result, Article (4)
Slack and sag detection switch (131) is turned on.This turns on the relay coil (9), closes the self-holding contact cA to self-hold relay 4, and opens relay contact t2v to lower the motor (2). The circuit Uη is turned off.This causes the motor (2) to stop.

Even if you take your hand off the lamp (6) in this state, the lamp (6)
It just descends by the amount of slack and comes to rest in a suspended state.

At this time, even if the sag detection switch (131) is turned off, the relay bet continues to be in a self-holding state, so the light fixture (6
) remains stationary at that position.

Therefore, compared to determining the position of the lamp (6) by operating the changeover switch ω on a wall that is away from the descending lamp (6), a much more preferable position of the lamp (6) can be determined. Then, after completing the work such as replacing the lamp, the light fixture (6
) to return it to its original position, move to the wall again and operate the changeover switch (151.) First, press this changeover switch U.
4 is returned to the neutral position from the descending circuit (1719111), the current to relay coil 4 is cut off, the self-holding contact t21 opens, and the V-contact 1211 closes.Then, the selector switch t151 is raised. circuit u
When switched to the 61 side, the motor drum (3) rotates clockwise to wind up the stub (4) and fully raise the lamp (6). Then, when the lamp (6) pushes up the control plate (9), the upper limit switch (8) is opened, the driving of the motor (2) is stopped, and the lamp (6) is set at the normal position.

In addition, in the above embodiment, an example was explained in which the method was used for lighting equipment, but in practice, it can be similarly used for equipment installed at a high place such as a camera. be. .

Effects of the Invention The present invention, as described above, uses the rotation of a motor drum to raise or lower an instrument attached to a stilt, and to stop the instrument at a desired position while lowering the instrument. Then, the sag detection switch operated and passed through the relay, which caused the relay to self-hold while disconnecting the motor's lowering circuit, so the device was stopped at the desired position. Moreover, even when the user takes his hand off the device, it remains stationary without descending again, making it extremely easy to replace the lamp and perform other necessary operations.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; Fig. 1 is a side view of the lamp in a fixed position, Fig. 2 is a side view of the lamp when it is stopped at a desired position during descent, and Fig. 3 is a side view of the lamp when it is stopped at a desired position. is an electrical circuit diagram. 2... Motor, 3... Motor drum, 4... Skull, 6... Light fixture (appliance), 13... Slack detection switch, 17... Lowering circuit, 18... Suv − Applicant: Toshiba Electric Materials Corporation

Claims (1)

[Claims] a motor drum driven by a motor in forward and reverse directions;
A stub wound around the motor drum, a device attached to one end of the stub, a sag detection switch for detecting slack in the stub caused by the weight of the device, and a sag detection switch for detecting the sag of the sag. 1iI consisting of a relay that is self-maintained and cuts off the descending circuit of the motor through switching operation! II7 Lifting device.