JP2002104782A - Ascending/descending device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ascending/descending device using a direct-current motor as a driving means for ascending/descending load, and a control circuit of the direct-current motor. SOLUTION: This ascending/descending device is provided with a hanging member; an ascending/descending portion to which the load can be connected; a fixed portion fixed to a ceiling of a structure and coupled with the ascending/ descending portion through the hanging member; and a driving means including a winding drum to which one end of the hanging member is connected and the direct-current motor for rotating the winding drum so as to wind up the hanging member, and enabling the ascending/descending portion to ascend/ descend by using the hanging member. The commercial power source is full- wave rectified by a diode bridge to drive the DC motor as a power source.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lifting device for a load such as a lighting fixture mounted at a high place, particularly a lifting device using a DC motor as a driving means for raising and lowering the load, and a control circuit for the DC motor. It is about.

[0002]

2. Description of the Related Art Conventionally, in a large structure having a relatively high ceiling such as a concert hall, a gymnasium, a convention hall, etc., a lighting fixture elevating device is used to facilitate maintenance of the lighting fixture mounted on the ceiling. I have. The lifting device is mainly a lifting unit to which the lighting equipment is connected,
It comprises a suspending member for suspending the elevating unit, a driving unit for raising / lowering the elevating unit via the suspending member, and a fixing unit for fixing the driving unit to the ceiling. As the driving means,
A winding drum to which one end of the hanging material is connected, and an AC motor that rotates the winding drum to wind the hanging material are used. With the lifting device having such a configuration, the lifting unit is moved between the uppermost position near the ceiling where the lighting fixture is used and the lowermost position lowered near the floor surface for maintenance of the lighting fixture. It becomes possible.

[0003]

However, in the case of using an AC motor, if the moving speed of the elevating section is to be increased, the reduction ratio of the speed reducer must be reduced, and a relatively large rotating force is required. It was necessary to use an AC motor.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to adjust the load lifting / lowering speed without using a large driving means. It is an object of the present invention to provide a lifting device capable of easily performing the above.

[0005] That is, a lifting device according to claim 1 of the present invention comprises at least one lifting member, a lifting portion to which a load can be connected, and a ceiling fixed to a structure, and is connected to the lifting portion via the lifting member. And a motor for rotating the take-up drum to take up the hanging material, and the lifting unit can be moved up and down by using the hanging material. An elevating device comprising a driving means and a control circuit for an electric motor, wherein the electric motor is a DC motor.

According to a second aspect of the present invention, in the first aspect of the present invention, the DC motor performs full-wave rectification of a commercial power supply by a diode bridge and drives the commercial power supply as a power supply.

According to a third aspect of the present invention, in the first or second aspect, the control circuit includes a single relay for switching the rotation direction of the DC motor.

According to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, the control circuit includes a relay which operates in response to a power supply on either the rising side or the falling side, and a relay contact. An ascending diode bridge used to apply power to the DC motor, and a descending diode used to apply power to the DC motor via a relay contact that opens and closes opposite to the ascending relay contact. And a bridge.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects of the present invention, the control circuit includes an ascending circuit that functions when the elevating unit moves up and a descending circuit that functions when the elevating unit descends. Has an ascending limit switch.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects of the present invention, the control circuit includes a rising side circuit that functions when the elevating unit rises and a descending side circuit that functions when the lifting unit descends. Has a descending limit switch.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects of the present invention, the control circuit includes an ascending circuit that functions when the elevating unit is ascending and a descending circuit that functions when the elevating unit descends. And each of the descending circuits has a surge absorber and a fuse for lightning surge countermeasures.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a lifting apparatus according to the present invention will be described below in detail with reference to the accompanying drawings. Although the load is not particularly limited, it is used by being placed at a high place (near a ceiling) and needs to be lowered to near the ground (floor surface) in order to perform its maintenance.
For example, lighting equipment, security cameras, fire detectors, banners, and the like can be given.

FIG. 1 shows an external view of a lighting apparatus elevating device according to this embodiment. The lifting device includes, as main components, a hanging member 2 formed of a pair of strips, a lifting unit 3 to which a lighting fixture can be connected at a lower portion, and a ceiling fixed to a structure. And a fixed portion 1 to be connected.

The hanging member 2 is preferably made of a rigid metal material or the like. There is no particular limitation on the number of hanging members, but when two or more are used, even if one of them is broken, the remaining lifting part 3 can be retained, which is preferable in terms of safety.

The fixed portion 1 is provided with a concave portion 1 in which the elevating portion 3 can be accommodated.
3 is provided on the lower surface of the case 10 and
There is provided a drive unit that enables the lifting unit to be moved up and down using the. The case 10 includes a base 12 fixed to the ceiling of the structure, and a cover 14 detachably attached to the base.

As shown in FIG. 2, the driving unit includes a pair of winding drums 20 to which one ends of the hanging members are connected for winding each of the hanging members 2, and a permanent magnet for rotating the winding drum. It includes a DC motor 22 having a commutation brush, and a reduction gear 26 that reduces the rotation of the drive shaft of the motor and transmits the rotation to the winding drum. In FIG. 2, a predetermined electric circuit including a control circuit of the DC motor is arranged in a region indicated by reference numeral 7.

As shown in FIG. 3, the suspension member 2 having one end connected to the take-up drum 20 extends vertically downward through the pulley 5 toward the elevating section 3. At this time, a pair of hanging members 2
Extend substantially parallel and so that the planes of the strips are substantially in the same direction. The rotation of the drive shaft of the DC motor 22 is transmitted via a reduction gear 26 to a spur gear 24 provided at one end of a main shaft 21 that is a rotation shaft of the pair of winding drums 20. Thereby, a pair of winding drums 20 can be rotated simultaneously and in the same direction.

In the above configuration, the DC motor 22
, The elevating unit 3 is moved to the uppermost position in which the concave portion 13 of the case 10 of the fixed unit 1 is
0, the lifting material 3 is completely removed from the lowermost position where the distance between the fixed part 1 and the lifting part 3 is maximized by completely releasing the hanging material 2.
Can be raised / lowered.

Next, a control circuit of the DC motor 22 in the lifting device according to the present invention will be described.

This control circuit is provided with a rising terminal a, a falling terminal b, and a common terminal c as shown in FIG.
Is raised, AC commercial power P is applied between the rising terminal a and the common terminal c, and when the lifting unit 3 is lowered, between the falling terminal b and the common terminal c, An AC commercial power supply P is applied. When a plurality of lifting devices (A, B) are installed as shown in FIG. 4, the commercial power supply P is applied by connecting the respective rising terminals a, falling terminals b, and common terminals c in parallel.

FIG. 5 shows an embodiment of the control circuit. The control circuit includes a first relay R1 having relay contacts R11 to R13 between an ascending terminal a and a common terminal c, and a relay contact R between a descending terminal b and a common terminal c.
A second relay R2 having 21 to R23 is provided. The rising terminal a is connected to the input terminal of the diode bridge DB1 via the contact R11 of the first relay R1, and the falling terminal b is connected to the same input terminal of the diode bridge DB1 via the contact R21 of the second relay R2. You. Further, the common terminal c is connected to the other input terminal of the diode bridge DB1, and is connected between an AC commercial power supply applied between the rising terminal a and the common terminal c, or between the falling terminal b and the common terminal c. The applied AC commercial power is full-wave rectified.

On the other hand, the output of the diode bridge DB1 is connected to the contact R12 and the contact R1 of the first relay R1 provided at both output terminals so that the DC motor 22 reverses the polarity.
Power is applied to the brush 22a of the DC motor 22 via the contact 3 and to the brush 22a of the DC motor 22 via the contact points R22 and R23 of the second relay R2 provided at the output end. FIG. 6A shows the operation state of this circuit (bold line) when the AC commercial power is applied between the rising terminal a and the common terminal c.
FIG. 6B shows the operation (thick line) of the control circuit when AC commercial power is applied between the control circuit and the common terminal c. Here, the contact R1 of the first relay R1 and the second relay R2
1, R21 is provided with a plurality of elevating and lowering devices, and prevents current from sneaking when each is connected in parallel.

In the control circuit shown in FIG. 5, two relays are used. However, as shown in FIG. 7, a single relay can be used. That is, a relay R1 having contacts R11 to R14 is provided between the rising terminal a and the common terminal c, the rising terminal a is connected to the input terminal of the diode bridge DB1 via the normally open contact R11, and the falling terminal b is normally closed. Is connected to the same input terminal of the diode bridge DB1 through the contact R12. In addition, diode bridge D
Switching contacts R13 and R14 are provided so that the DC motor 22 reverses the polarity of the output of B1. The relay is provided between the rising terminal a and the common terminal c, but may be provided between the falling terminal b and the common terminal c.

FIG. 8 shows an embodiment of a control circuit constituted by a normally open and normally closed contact without using a switching contact with a single relay. This control circuit provides a relay R1 between a rising terminal a and a common terminal c, and a first and second diode bridge DB between a rising terminal a and a common terminal c and between a falling terminal b and a common terminal c.
1. By providing DB2, the AC commercial power applied between the rising terminal a and the common terminal c or the AC commercial power applied between the falling terminal b and the common terminal c can be full-wave, respectively. It is rectifying.

The output of the first diode bridge DB1 is provided with normally open first and second contacts R11 and R12 of a relay R1 at both output terminals, and is connected to a brush 22a of a DC motor 22. The output of the diode bridge DB2 has normally closed third and fourth contacts R13 and R14 of the relay R1 at both output terminals, and is connected to the brush 22a of the DC motor 22. FIG. 9A shows an operation state (thick line) of this control circuit when AC commercial power is applied between the rising terminal a and the common terminal c. FIG. 9B shows the operation state (thick line) of the control circuit when AC commercial power is applied. Relay R
1 is provided between the rising terminal a and the common terminal c, but the falling terminal b
And between the common terminal c.

As shown in FIG. 10, the ascending limit switch LS1, which is opened when the elevating unit 3 reaches the uppermost position, is interposed in series with the ascending terminal a, and as shown in FIG. By interposing a descent limit switch LS2 that opens when the elevating unit 3 reaches the lowermost position in series with the lowering terminal b, the DC motor 22 is connected to the elevating unit 3 when the elevating unit 3 reaches the uppermost position or the lowest position. Can be automatically stopped by shutting off the power supply.

Further, as shown in FIG.
Absorbers ZNR1 and ZNR2 for passing a current when a large voltage such as a lightning surge is superimposed between the common terminal c and the descending terminal b and the common terminal c. When a fuse H that cuts off the circuit when a current flows is interposed, the diode bridges DB1 and DB2 and the contact R1 are caused by a large voltage such as a lightning surge.
1, R12, R13, and R14 can be prevented from being damaged.

[0028]

Conventionally, as a result of reducing the reduction ratio of the speed reducer in order to increase the rotation speed of the winding drum, that is, the speed of elevating the elevating section, it has been necessary to use a large AC motor. In the present invention, since a DC motor is used as the driving means, the size of the apparatus can be reduced and the load elevating speed can be easily adjusted as compared with the case where an AC motor is used.

Further, when the control circuit of the DC motor is constituted by using two relatively inexpensive diode bridges and a single relay, the cost of the entire apparatus can be reduced, and the number of relay contacts can be reduced to reduce the circuit. Connection cost can be reduced.

The lifting apparatus according to the present invention is particularly suitable for use in large structures having relatively high ceilings such as concert halls, gymnasiums, and convention halls, and performs maintenance work for loads such as lighting fixtures arranged at high places. Can be performed efficiently.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an external appearance of a lifting / lowering device for a lighting fixture according to an embodiment of the present invention.

FIG. 2 is a schematic top view showing an internal configuration of a fixing portion of the lifting device.

FIG. 3 is a schematic cross-sectional view showing an internal configuration of a fixing unit of the above.

FIG. 4 is a diagram showing feed wiring when a plurality of lifting devices are installed.

FIG. 5 is a diagram showing a first embodiment of a control circuit of a driving unit.

6A is a diagram showing an operation of the control circuit when AC commercial power is applied between the rising terminal a and the common terminal c in FIG. 5, and FIG. 6B is a diagram showing FIG. FIG. 5 is a diagram showing an operation of the control circuit when AC commercial power is applied between the falling terminal b and the common terminal c.

FIG. 7 is a diagram showing a second embodiment of the control circuit of the driving means.

FIG. 8 is a diagram showing a third embodiment of the control circuit of the driving means.

9A is a diagram illustrating an operation of the control circuit when AC commercial power is applied between the rising terminal a and the common terminal c in FIG. 8, and FIG. 9B is a diagram illustrating the operation of the control circuit. FIG. 5 is a diagram showing an operation of the control circuit when AC commercial power is applied between the falling terminal b and the common terminal c.

FIG. 10 is a diagram illustrating an example of a control circuit provided with an ascending limit switch.

FIG. 11 is a diagram illustrating an example of a control circuit provided with a lower limit switch;

FIG. 12 is a diagram illustrating an example of a control circuit provided with a lightning surge suppression circuit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixed part 2 Suspension material 3 Elevating part 5 Pulley 10 Case 12 Base 14 Cover 20 Winding drum 22 DC motor

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasuhiro Miyazaki 1048 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Works Co., Ltd. (72) Inventor Shiro Nakajima 5-66 66 Shioe, Amagasaki City, Hyogo Prefecture (72) Inventor Koji Yamashita 1048 Kazuma Kadoma, Kadoma City, Osaka Inside Matsushita Electric Works, Ltd.

Claims (7)

[Claims] At least one hanging member, a lifting part capable of connecting a load, a fixed part fixed to a ceiling of a structure, and connected to the lifting part via the hanging member, A drive unit that includes a winding drum having one end connected thereto and an electric motor for rotating the winding drum to wind the hanging material, and a driving unit that allows the lifting unit to move up and down by using the hanging material; And a control circuit, wherein the electric motor is a DC motor. 2. The lifting device according to claim 1, wherein the DC motor performs full-wave rectification of a commercial power supply using a diode bridge and drives the commercial power supply as a power supply. 3. The elevating device according to claim 1, wherein the control circuit includes a single relay for switching a rotation direction of the DC motor. 4. A control circuit comprising: a relay that operates in response to a power supply on either a rising side or a falling side; and a rising side diode bridge used to supply power to a DC motor via a relay contact. And a descending diode bridge used to supply power to the DC motor through a relay contact that opens and closes in reverse to the ascending relay contact. An elevating device according to any of the claims. 5. The control circuit includes an ascending circuit that functions when the elevating unit rises and a descending circuit that functions when descending.
The lifting device according to any one of claims 1 to 4, wherein the ascending side circuit has a rising limit switch. 6. The control circuit includes an ascending circuit that functions when the elevating unit is ascending and a descending circuit that functions when the elevating unit descends.
The lifting device according to any one of claims 1 to 5, wherein the descending side circuit has a descending limit switch. 7. The control circuit includes an ascending circuit that functions when the elevating unit moves up and a descending circuit that functions when it moves down.
The lifting device according to claim 1, wherein each of the rising side circuit and the falling side circuit has a surge absorber and a fuse for lightning surge countermeasures.