JP2003208812A - Lifting and lowering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stop and hold an object to be lifted and lowered at a desired position in the middle of lifting or lowering it without newly adding a relay or the like. <P>SOLUTION: In this illumination lifting and lowering device, the b contact side of the two contacts 24, 25 of a relay R2 having a plurality of contacts 23-25 to switch a DC motor is connected to the lifting circuit side, and the a contact side is connected to the lowering circuit side. Thereby, if a stopping operation is applied in the middle of lowering the object to be lifted and lowered, since the contact of the relay R2 is switched to the b contact side by stoppage of power supply, and a circuit including the DC motor 8 is brought into a short-circuited condition. the object to be lifted and lowered can be stopped and held at that position by instantly applying a brake by the power generating action of the DC motor 8, without newly adding a relay or the like. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lifting device installed on a high ceiling such as a gymnasium or a hall.

[0002]

2. Description of the Related Art Lighting fixtures installed on a high ceiling are
Attached to lifting equipment for maintenance / inspection.

A conventional lifting device is disclosed in Japanese Patent Publication No. 25824.
As shown in No. 85, the lamp 33, the lighting fixture 3
An elevating mechanism for elevating the elevating part 31 including 4 up and down, and a wire 25 for suspending the lighting fixture 34 on the elevating mechanism.
Ascending / descending switch 52 for detecting that the elevating / lowering unit 31 has reached the upper end position of the elevating / lowering mechanism, detecting means 26 for detecting the slack of the wire 25, that is, the elevating / lowering unit 31 being fully lowered, and the detecting means 26 and the ascending movement. Stop switch 52
And a control circuit for controlling the lifting mechanism according to the above condition. The lifting mechanism uses an electric motor 22 such as a DC motor and a winding drum 23 as driving means.

In the case of the lifting device using such a DC motor, the lifting part 31 is lowered, and when the lifting part 31 reaches the floor surface and the wire 25 sags, it is detected by the detection means 26. For the first time, the control circuit stops driving the DC motor and stops the lowering operation.

By the way, regarding such a lifting device,
There is a demand to stop the elevating part 31 at a desired position while descending or ascending depending on the usage situation of the user.

In the conventional lifting device, since the lifting mechanism does not use a hardware mechanism such as a brake for stopping during lifting, DC is required to stop the lifting unit 31 during lifting. It is conceivable to electrically stop the rotation of the motor by utilizing the power generation action of the DC motor by electrically short-circuiting the terminals of the motor using some means, for example, a relay.

[0007]

However, since many relays such as a descending relay, a reversing relay, and a motor switching relay are already used in the conventional lifting device, in view of cost and arrangement space, There was a problem that it was not possible to add another relay just because the motor was short-circuited halfway.

Further, in the case of the conventional lifting device, since the lowering operation is stopped only after the slack of the wire is detected by the switch, there is a slight timing deviation until the rotation of the DC motor is stopped, and the wire overrun occurs. However, there was a problem in that the wire could not be stopped at the intended position.

The present invention has been made to solve such a problem, and is a low-cost and small-sized lifting device capable of reliably stopping and holding the movement of the object to be lifted or the feeding of the wire at a desired position. Is intended to provide.

[0010]

In order to achieve the above-mentioned object, the invention according to claim 1 is a DC motor for raising or lowering an object to be raised or lowered; and an ascent for rotating the DC motor to an ascending side. A circuit; a down circuit for rotating the DC motor to the down side; a motor switching relay for switching a terminal of the DC motor to one of the up circuit and the down circuit; and a circuit connected to the down circuit, A first contact that conducts when a power is supplied to the motor switching relay; and a second contact that is connected to the rising circuit and conducts when a power is not supplied to the motor switching relay. It is characterized by that.

According to a second aspect of the present invention, a wire suspending an object to be raised and lowered; a DC motor for raising or lowering the object to be raised or lowered by the wire; a raising circuit for rotating the DC motor to an ascending side. A down circuit for rotating the DC motor to the down side; a motor switching relay for switching a terminal of the DC motor to one of the up circuit and the down circuit; and the motor connected to the down circuit. A first contact that conducts when power is applied to the switching relay; a second contact that is connected to the ascending circuit and conducts when power is not applied to the motor switching relay; and a descending circuit A switch that is connected and turns on when the wire is stretched and turns off when the wire sags;
A slack detecting relay connected in series to the switch in the descending circuit; and a third short circuit between the first contacts connected to both ends of the DC motor when the slack detecting relay is not energized. And contact points of.

When a DC motor is used to raise and lower an object to be moved up and down, a raising circuit for rotating the DC motor to the ascending side, a descending circuit for rotating the descending side, and one of these ascending circuit and descending circuit are usually used. It is necessary to provide a motor switching relay for switching the connection between one of them and the DC motor. In the present invention, two contacts of this motor switching relay are respectively provided between the motor terminals, and among the contacts, The first contact (a contact side) that conducts when the power source is energized is connected to the descending circuit, and the second contact (b contact side) that conducts when the power source is not energizing is connected to the ascending circuit. Then, each circuit can be short-circuited when the power supply is cut off.

In the present invention, when the operation switch is operated to the lower side in order to lower the object to be moved up and down, power is supplied to the motor switching relay, so that the DC motor is operated to the lower side. When the operation switch is stopped in the middle of lowering, power is not supplied to the motor switching relay, so the contact of the motor switching relay is switched to the b contact side, and the DC motor terminals are short-circuited. The brake is applied.

On the other hand, if the object to be moved up and down is stopped while the object is being raised, the contact of the motor switching relay remains in the b-contact state, power is not supplied to the DC motor, and the terminals of the DC motor are short-circuited. Brakes are applied as above. In addition, in order to ensure switching of the contacts when power is not supplied, it is preferable that the descending circuit side is the a-contact.

Further, according to the present invention, in the elevating device having the ascending / descending circuit for operating the DC motor, the third contact of the wire slack detecting relay is connected to the a contact on the descending circuit side.

When power is no longer supplied to the slack detecting relay when the slack of the wire is detected by lowering the object to be lifted and lowered, the third contact of the relay is switched from the a contact side to the b contact side. Therefore, the voltage is not supplied to the DC motor, and the circuit of the relay is closed by the b contact, so the circuit including the DC motor is short-circuited and the power generation by the DC motor causes the brake to be applied and the wire to be drawn out instantly. It can be stopped.

That is, according to the present invention, the object to be lifted and lowered can be stopped and held at that position without adding a relay. Further, when the object to be lifted and lowered is stopped and the wire is stopped to be fed when the object to be lifted reaches the floor surface or the like, it is possible to prevent the wire from being unwound too much and the occurrence of overrun.

As a result, it is possible to provide a low-cost and small-sized lifting device which can surely stop and hold the movement of the object to be lifted or the feeding of the wire at a desired position.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing an overall configuration of an illumination lifting / lowering device according to an embodiment of the present invention.

As shown in the figure, this lighting lifting device is
For example, a lock case 1 fixed to a lifting device body attached to a high ceiling of a gymnasium, and the lock case 1
A contact table 2 as a movable body that can move up and down, and an object to be moved up and down through the contact table 2 and a lock case 1 (a lighting mounting case 3 and a lighting fixture 4 and a lamp mounted on the lighting mounting case 3). Wire 5 for hanging 4a)
A cam 6 for locking and unlocking the object to be lifted and lowered in the lock case 1, a winding drum 7 as a winding means for winding the wire 5, and an object to be lifted by rotationally driving the winding drum 7. DC motor 8 that raises and lowers the
A power source 9 for supplying power to the motor 8 via either the diode bridge D1 or the diode bridge D2 (see FIG. 2), and a select switch 10 (hereinafter referred to as select SW1) for the user to perform operations such as raising, stopping, and lowering.
0)) and a plurality of micro switches L1, L2, L
3 (see FIG. 2) and relays R1, R having a plurality of contacts
2 (see FIG. 2) and R3 (see FIG. 3).

The contact base 2 is constantly urged downward by an urging member such as a spring, and after the lighting mounting case 3 comes up and contacts the contact base 2, it is pushed upward by the lighting mounting case 3.

The micro switch L1 is a switch for reversing when released. The micro switch L2 is a switch for reversing when locked, which turns on and off according to the vertical movement of the contact base 2. Specifically, the micro switch L2 is turned on when the step portion of the lighting mounting case 3 is locked (locked) by the cam 6, the lighting mounting case 3 rises from that position, and approaches the back surface of the locking case 1. It turns off when the cam 6 comes off.
The micro switch L3 is a slack detecting micro switch that is turned on / off by detecting the tension state of the wire 4. Specifically, the micro switch L3 is a wire 5
It turns on while it is stretched, and turns off when it sags.

As shown in FIG. 2, the first embodiment of the raising / lowering control circuit of this lighting raising / lowering device has two relays R1 and R2.
And three micro switches L1, L2, L3, a capacitor C connected to both ends of the DC motor 8, and rising (black)
Of the fuse F connected between the contact line of the relay R1 and the contact 21 of the relay R1, a descending circuit constituted by a contact of the contacts 24 and 25 of the DC motor 8 and the relay R2, and a circuit such as a diode bridge D2, and the DC motor 8. Contact 2 of relay R2
It has 4,25 b-contacts and a rising circuit constituted by a circuit such as a diode bridge D1. The capacitor C is for noise prevention. The fuse F is for preventing wrong distribution.

The relay R1 is a relay having two contacts 21 and 22 and is connected between the descending (red) line and the common (white) line and operates for descending.

The relay R2 is a relay having three poles of contacts 23 to 25, and is connected between two microswitches L1 and L2 and a contact 22 of the relay R1 and a common (white) line, Each contact is connected so as to perform two functions of reversing and switching of the motor.

That is, the two contacts 2 of the relay R2 which is a motor switching relay for switching between the ascending circuit and the descending circuit.
Of the 4, 25, the b contact ● side, that is, the side that conducts when the power source is not energized, is connected to the rising circuit side, and the a contact ○ side, that is, the side that conducts when the power source is energized, is connected to the descending circuit side. ing.

The operation of the illumination lifting / lowering device having the illumination lifting / lowering circuit of the first embodiment will be described below. In this lighting lifting device, when lowering the lighting fixture 4 that is hung at a high position such as a high ceiling of a gymnasium, the operator lowers the select SW 10.

Then, the ascending circuit operates, the DC motor 8 rotates to the ascending side, and the ascending / descending target object ascends once. And
When the cam 6 is disengaged, the micro switch L2 is turned off and unlocking is detected.

Then, the relay R2 is switched to the a-contact side, the descending circuit side is energized, the direction of the current to the DC motor 8 is reversed, and the rotating drum 7 rotates to the descending side so that the wire 5 is paid out. Then, the ascending / descending object starts descending.

When the object to be lifted and lowered further reaches the floor surface and the tension of the wire 5 is loosened and the wire 5 sags, the micro switch L3 is turned off and the power is not supplied to the relay R2. .

Then, the contact of the relay R2 is switched from the a contact ○ side to the b contact ● side, so that no voltage is supplied to the DC motor 8 and the relay R2 has the circuit closed at the b contact. The down circuit including 8 is short-circuited, and the DC motor 8 can be stopped instantaneously. At the same time, the rotation of the rotary drum 7 is stopped and the feeding of the wire 5 is stopped.

Further, when the operator stops the select SW10 while lowering the object to be moved up and down, the power supply to the relay R2 is stopped. At that moment, the contact point of the relay R2 is switched from the a contact side to the b contact side. , The terminals of the DC motor 8 are short-circuited, the DC motor 8 applies a brake, and the lifting target can be stopped and held at that position.

On the other hand, if the object to be moved up and down is stopped while the object is being lifted, the DC motor 8 will not be supplied with power while the relay R2 remains in the b-contact state, so that the terminals of the DC motor 8 will be short-circuited. The brake is applied by 8 and can be stopped and held as described above.

As described above, according to the lighting elevating / lowering device adopting the lighting elevating / lowering circuit of the first embodiment, the b contact side of the two contacts 24 and 25 of the relay R2 having a plurality of contacts for switching the DC motor 8, That is, the side that conducts when the power is not energized is connected to the ascending circuit side, and the side that contacts when the power is energized, that is, the side that conducts when the power is energized is connected to the descending circuit side. When stopped, the contact of the relay R2 is switched to the b contact side, and the circuit including the DC motor 8 is short-circuited. Therefore, the DC motor 8 can be instantly braked to accurately stop and hold the lifting target at that position. it can.

Next, with reference to FIG. 3, a second embodiment of the lighting lifting circuit applied to the lighting lifting device of FIG. 1 will be described.

As shown in FIG. 3, the second embodiment of the raising / lowering control circuit of this lighting raising / lowering device has three relays R1 and R1.
2, R3 and three micro switches L1, L2, L3
And a capacitor C connected to both ends of the DC motor 8,
The fuse F connected between the rising (black) line and the contact 21 of the relay R1 and the contact 2 of the DC motor 8 and the relay R2
4, 25 a contact and a down circuit composed of a circuit such as a diode bridge D2, a DC motor 8 and a relay R
2 contacts 24 and 25 b contacts and diode bridge D1
And a rising circuit configured by a circuit such as.
The capacitor C is for noise prevention. The fuse F is for preventing wrong distribution.

The relay R1 is a relay having two contacts 21 and 22 and is connected between the descending (red) line and the common (white) line and operates for descending.

The relay R2 is a relay having three poles of the contacts 23 to 25, and is connected between the two microswitches L1 and L2 and the contact 22 of the relay R1 and the common (white) line. Each contact is connected so as to perform two functions of reversing and switching of the motor.

That is, the two contacts 2 of the relay R2 which is a motor switching relay for switching between the ascending circuit and the descending circuit.
Of the 4, 25, the b contact ● side, that is, the side that conducts when the power source is not energized, is connected to the rising circuit side, and the a contact ○ side, that is, the side that conducts when the power source is energized, is connected to the descending circuit side. ing.

The relay R3 is a relay having two poles of contacts 26 and 27, and is connected in series with the micro switch L3. The contact 26 of the relay R3 functions for holding and stopping the arbitrary position, and the contact 27 of the relay R3 functions for holding the motor. That is, this relay R3 has two functions, one for holding and holding the arbitrary position and one for holding the motor.

The operation of the illumination lifting / lowering apparatus having the illumination lifting / lowering circuit of the second embodiment will be described below. In this lighting lifting device, when lowering the lighting fixture 4 that is hung at a high position such as a high ceiling of a gymnasium, the operator lowers the select SW 10.

Then, the ascending circuit operates, the DC motor 8 rotates to the ascending side, and the object to be elevated and lowered is temporarily elevated. And
When the cam 6 is disengaged, the micro switch L2 is turned off and unlocking is detected.

Then, the relay R2 becomes the a-contact side and is energized to the descending circuit side, the direction of the current to the DC motor 8 is reversed, and the rotating drum 7 rotates to the descending side to pay out the wire 5. , The object to be lifted and lowered begins to descend.

When the lifting object reaches the floor surface,
The tension of the wire 5 is loosened and the wire 5 sags.

Then, the micro switch L3 is turned off,
Power is not supplied to the relays R2 and R3.

Then, the contact of the relay R2 is switched from the a contact ● side to the b contact ○ side, so that no voltage is supplied to the DC motor 8 and the circuit of the relay R2 is closed at the b contact side, so that the DC motor 8 side is closed. The descending circuit including is short-circuited, and the DC motor 8 can be stopped instantaneously. At the same time, the rotation of the rotary drum 7 is stopped and the feeding of the wire 5 is stopped.

When power is not supplied to the relay R3, the contacts 24, 25, 26 and 27 of the relays R2 and R3 are also supplied.
Changes to the ○ side, and in particular, both ends of the DC motor 8 are short-circuited by the contacts 27, so that the DC motor 8 is instantly braked and the rotation of the rotary drum 7 is stopped at the same time, so that the object to be lifted reaches the floor surface. It is possible to stop the descending operation of the ascending / descending object at the moment of doing.

If the operator stops the select SW10 while lowering the object to be raised or lowered, the relay R2 is no longer supplied with power. At that moment, the contact of the relay R2 is switched from the a-contact side to the b-contact side. , The terminals of the DC motor 8 are short-circuited, the DC motor 8 applies a brake, and the lifting target can be stopped and held at that position.

On the other hand, if the object to be moved up and down is stopped while the object is being raised, the DC motor 8 will not be supplied with power while the relay R2 remains in the b-contact state, and the terminals of the DC motor 8 will be short-circuited. The brake is applied by means of 8 and can be stopped in the same manner as above.

As described above, according to the lighting elevating / lowering device adopting the lighting elevating / lowering circuit of the second embodiment, when the object to be lifted and lowered reaches the floor surface and the micro switch L3 is turned off. , The power supply to the relay R3 is stopped, the contacts 27 are instantly turned on and both ends of the DC motor 8 are short-circuited, the DC motor 8 is instantly braked, and the rotation of the rotary drum 7 is stopped at the same time. The feeding of the wire 5 can be stopped at the moment when the lifting target reaches the floor surface.

As a result, for example, it is possible to prevent the wire 5 from being overwound too much.

As described above, according to the lighting elevating / lowering device to which the lighting elevating / lowering circuit of each embodiment is applied, the a contacts of the contacts 24 and 25 of the relay R2 for switching between the ascending circuit and the descending circuit are connected to the descending circuit side. By connecting the b contact to the rising circuit side,
It is possible to stop the object to be lifted or lowered while adding or removing a short-circuit switch member such as a relay.

Further, in the descending circuit, the relay R3 and its contact 2
By providing 6, 27, a at both ends of the DC motor 8 at the moment when the micro switch L3 is turned off and the power supply is stopped.
Since the contacts are short-circuited by the contacts 27 and the brake is applied by the power generation action of the DC motor 8, the feeding of the wire 5 is stopped at the moment when the power supply is stopped.
It is possible to prevent the occurrence of overrun.

As a result, it is possible to provide a low-cost and small-sized lifting device which can surely stop and hold the movement of the lifting object or the feeding of the wire 5 at a desired position.

[0055]

As described above, according to the present invention, it is possible to provide a low-cost and small-sized lifting device capable of reliably stopping and holding the movement of the object to be lifted or the wire feeding out at a desired position.

[Brief description of drawings]

FIG. 1 is a diagram showing an overall configuration of an illumination lifting / lowering device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a first embodiment of a lifting control circuit of this lighting lifting device.

FIG. 3 is a diagram showing a second embodiment of a lifting control circuit of this lighting lifting device.

[Explanation of symbols]

1 ... Lock case 2 ... Contact block 3 ... Lighting mounting case 4 ... Lighting equipment 4a ... Lamp 5 ... Wire 6 ... cam 7 ... Winding drum 8 ... DC motor 9 ... Power 10 ... Select switch (Select SW) 21 to 27 ... Relay contacts R1, R2, R3 ... Relay L1, L2, L3 ... Micro switch

Claims (2)

[Claims] 1. A DC motor for raising or lowering an object to be raised or lowered; a raising circuit for rotating the DC motor to an ascending side; a descending circuit for rotating the DC motor to a descending side; the ascending circuit and the descending circuit. A motor switching relay for switching a terminal of the DC motor to one of the circuits; a first contact connected to the descending circuit and conducting when a power is supplied to the motor switching relay; And a second contact which is connected to a rising circuit and which conducts when power is not supplied to the motor switching relay. 2. A wire for suspending an object to be raised and lowered; a DC motor for raising or lowering the object to be raised or lowered by the wire; a raising circuit for rotating the DC motor to an ascending side; A descending circuit for rotating to the descending side; a motor switching relay for switching the terminal of the DC motor to one of the ascending circuit and the descending circuit; and a power source connected to the descending circuit and connected to the motor switching relay. A first contact that conducts when energized; a second contact that is connected to the ascending circuit and that conducts when a power source is not energized to the motor switching relay; a wire that is connected to the descending circuit and has the wire A switch that turns on in a stretched state and turns off when it sags; a slack detection relay connected in series to the switch in the descending circuit; the slack detection relay And a third contact for short-circuiting the first contacts connected to both ends of the DC motor when the power source is not energized.