JP2004207031A - Electric hoisting/lowering device of electric apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric hoisting/lowering device of an electric apparatus capable of relatively correctly controlling a stop position of the electric apparatus. <P>SOLUTION: A motor control circuit 24 of this electric hoisting/lowering device 1 stops the drive of a motor 7 when a count value of a counter 23 for counting pulse signals outputted by an encoder 21 reaches a predetermined value indicating the lower limit value in lowering a luminaire suspended by a wire rope by driving the motor 7 to rotate a reeling drum. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electric hoisting device that raises and lowers an electric device by rotating a winding drum by a motor and winding and rewinding a rope to which an electric device is connected at a distal end.
[0002]
[Prior art]
As an electric lifting device for raising and lowering an electric device attached to the tip of a wire rope, for example, Patent Document 1 discloses measuring the time from the time when the lowering of the electric device is started, and rotating the motor after a predetermined time elapses. There has been disclosed a technique in which a descent stop position is controlled by stopping.
[0003]
[Patent Document 1]
JP-A-7-272527
[0004]
[Problems to be solved by the invention]
However, in the technology disclosed in Patent Document 1, there is a problem that the stop position is slightly shifted because the weight of the electric device has a slight variation or the number of revolutions of the motor changes when the power supply voltage changes. .
[0005]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a motor-driven elevating device for an electric device that can more accurately control a stop position of the electric device.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, an electric lifting device for electric equipment according to claim 1 is configured such that a rope to which the electric equipment is connected at a tip, a winding drum for winding the rope, and the winding drum are rotated. And a motor comprising:
Pulse generating means attached to the motor, for outputting a pulse signal with rotation of the motor,
Counting means for performing a counting operation based on the output state of the pulse signal;
Control means for controlling so as to stop driving the motor when the count value of the count means reaches a predetermined value indicating a lower limit position when the electric device is lowered by driving the motor. It is characterized by having.
[0007]
With such a configuration, when the control unit drives the motor to rotate the winding drum, the rope is sent out and the electric device connected to the tip of the rope descends. At this time, the pulse generation means outputs a pulse signal in accordance with the rotation of the motor, so that the control means can grasp the descending position of the electric device from the count value based on the output of the pulse signal. Then, if the driving of the motor is stopped when the count value of the counting means reaches a predetermined value, the electric device can be stopped accurately at the lower limit position.
[0008]
In this case, as described in claim 2, the pulse generating means is configured to output a two-phase pulse signal having a different phase relationship according to the forward / reverse rotation of the motor,
Pulse conversion means for converting the two-phase pulse signal into an up-count pulse signal and a down-count pulse signal according to the phase relationship and outputting the converted signal;
The counting means may be configured to perform an up / down counting operation based on the output state of the up-count pulse signal and the down-count pulse signal.
[0009]
With such a configuration, the control unit can grasp the position of the electric device even when the rope is wound by the winding drum and the electric device rises. Therefore, even when the descending operation and the ascending operation are intermittently repeated, the control means can accurately grasp the position of the electric device.
[0010]
Further, as described in claim 3, the pulse generating means includes a disk-shaped magnet attached to the rotating shaft of the motor and magnetized to n poles (n is a multiple of 2); It is preferable to use two Hall elements arranged so that the phase difference between the output two-phase pulse signals is 90 degrees.
[0011]
With this configuration, the 90-degree phase difference between the two-phase pulse signals advances with reference to the phase of one of the signals and changes with a delay in accordance with the rotation direction of the motor. By detecting the change in the delay, it is possible to determine the rotation direction of the motor, that is, determine whether the electric device is moving up or down, and output an up-count pulse signal and a down-count pulse signal.
[0012]
In the above case, as described in claim 4, an upper limit position detecting unit that detects that the electric device has reached the upper limit position and outputs a detection signal,
The counting means may be configured so that the count value is set to an initial value when the detection signal is output. That is, since the upper limit position is a reference for control, if the upper limit position detecting means detects that the upper limit position has been reached and the count value of the counting means is set to the initial value, there is a possibility that an error occurs in the control. Can be smaller.
[0013]
Further, as described in claim 5, a slack detecting means for detecting slack of the rope,
The control means may be configured to set the count value indicated by the count means as the lower limit position when the slack is detected while the electric device is being lowered.
[0014]
For example, if the electric device is stopped by lowering the electric device by contacting any object before reaching the lower limit position set initially, that is, the rope is slackened. Will do. Therefore, when the looseness is detected by the looseness detecting means, the count value at that time is reset as the lower limit position, so that the unnecessary descending operation can be prevented from continuing.
[0015]
Further, with such a configuration, for example, even when the user wants to reset the lower limit above the lower limit position that was initially set, with the intention that the user wants to reset the lower limit by hand, for example, , Can be set as the lower limit position.
[0016]
In this case, as described in claim 6, when the slack is detected when the count value of the counting means indicates the set lower limit position, the lower limit position is cleared and the initial value is set. It may be configured to return to.
[0017]
With such a configuration, when the user wants to clear and initialize the lower limit position reset by the user, if the user lifts the electric device at the lower limit position slightly with a hand, for example, the slackness of the rope is reduced. This can clear the lower limit position.
[0018]
In addition, in the above case, as described in claim 7, a power supply cutoff detecting unit that detects that the power supply has been cut off is provided,
The control means is configured to store the count value of the counting means in the storage means when the interruption of the power supply is detected, read out the count value stored in the storage means when the power supply is restored, and set the count value as the current position. Good.
[0019]
That is, for example, when the power is cut off due to a power failure or the like, the count value of the counting means is cleared, and when the power is restored, the current position of the electric device becomes unknown, which hinders subsequent control. Therefore, according to the present invention, the count value of the counting means at the time when the power supply is detected to be shut off is stored in the storage means, so that the stored count value is read out when the power supply is restored. The current position can be obtained, and control can be continued.
[0020]
Further, in the above case, the electric device may be a lighting device. That is, for example, when the present invention is applied to a lighting fixture configured to be hung from a ceiling in a house, the height position of the lighting fixture can be easily controlled.
[0021]
In addition, any one of claims 1 to 4, further comprising a slack detecting means for detecting slack of the rope,
When the slack is detected while the electric device is being lowered, the control means sets a count value corresponding to a position slightly above the count value indicated by the count means at that time as a lower limit position. May be configured.
[0022]
For example, if the electric device is stopped by lowering the electric device by contacting any object before reaching the lower limit position set initially, that is, the rope is slackened. Will do. Therefore, if the looseness is detected by the looseness detecting means, the position slightly higher than the count value at that time is reset as the lower limit position, and when the electric device is subsequently lowered, the object is detected. Contact can be reliably avoided.
[0023]
Further, in the above case, the lowering operation is stopped by the user's operation before the electric device being lowered reaches the lower limit position set as the initial value, and thereafter, the electric device is switched to the ascending operation to change the electric device. May reach the upper limit position, the stop position during the lowering operation may be set as the lower limit position. With this configuration, by executing the above procedure, the lower limit position desired by the user can be set.
[0024]
In this case, when the user performs an operation for starting the ascent operation a predetermined number of times in a state where the electric device is at the upper limit position, the control unit clears the lower limit position set by the user and returns to the initial lower limit position. You may make it reset. With such a configuration, it is possible to set the lower limit position and initialize the lower limit position only by the operation means for giving the ascending and descending instructions to the control means.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment in which the present invention is applied to a lighting fixture will be described with reference to the drawings. In FIG. 2 showing the overall configuration, a plurality of electric lifting devices 1 are arranged, for example, behind a ceiling in a house, and a plurality of lighting devices (electric devices) 2 suspended from the ceiling are connected to a wire rope. It goes down and rises all at once. A commercial AC power supply 3 is supplied to each electric lifting device 1 via a breaker 4 and a lifting switch 5.
[0026]
FIG. 3 shows a configuration centered on the electric lifting device 1. The electric lifting device 1 includes an AC motor 7 composed of, for example, an induction motor, and a winding drum 9 coupled to a rotating shaft of the motor 7 for winding or rewinding the wire rope 8 inside the main body case 6. And so on. The wire rope 8 is routed through a plurality of wire guards 10, and an elevating body 11 for connecting and supporting the lighting fixture 2 is connected to a tip of the wire rope 8 so as to suspend them. When the wire rope 8 is unwound by the winding drum 9, the lighting fixture 2 descends, and when the wire rope 8 is wound, the lighting fixture 2 rises.
[0027]
Further, a limit switch (upper limit position detecting means) 12 is disposed inside the main body case 6 in order to detect an upper limit position at which the upper surface 11a of the elevating body 11 comes into contact with a ceiling surface when the lighting fixture 2 rises. That is, at the same time that the upper surface 11a of the elevating body 11 comes into contact with the ceiling surface, the convex portion 11b formed so as to stand upright on the upper surface 11a is provided with an operating member (not shown) of the limit switch 12 inside the main body case 6. ), The limit switch 12 is turned on.
[0028]
Further, between the wire guards 9, a slack detection mechanism (slack detection means) 13 for detecting slack (reduction in tension) of the wire rope 8 is arranged. As shown in FIG. 4 (in FIG. 4, the upper side in FIG. 3 is set to the left), the slackness detection mechanism 13 is a photoelectric sensor for detecting a displacement of the support shaft 15 on both sides of the frame 14. An element 16a and a light receiving element 16b are arranged. A spring 17 for urging the support shaft 15 in a direction opposite to the frame 14 is disposed between the support shaft 15 and the frame 14. A roller 18 for receiving the wire rope 8 is supported between the two support shafts 15.
[0029]
As shown in FIG. 4A, in a state where the lighting fixture 2 and the lifting / lowering body 11 are suspended and a constant tension acts on the wire rope 8, the roller 18 and the support shaft 15 are moved by the tension. Is pressed in the frame direction against the urging force of the spring 17. Then, the optical path between the light emitting element 16a and the light receiving element 16b is blocked by the rear end of the support shaft 15.
[0030]
Then, as shown in FIG. 4B, when the lighting fixture 2 and the elevating body 11 are supported by, for example, some object, the tension acting on the wire rope 8 is reduced, and the roller 18 and the support shaft 15 Is displaced in the direction opposite to the frame due to the urging force. Then, the rear end of the support shaft 15 also moves, so that the light receiving element 16b can receive the light emitted from the light emitting element 16a, and the slack of the wire rope 8 is detected.
[0031]
FIG. 1 is a functional block diagram showing an electric configuration of the electric lifting device 1. On the rotating shaft of the motor 7, a disk-shaped magnet (disk-shaped magnet) 19 whose outer peripheral portion is magnetized to two poles (n = 2) is attached. Two Hall ICs 20A and 20B are arranged so as to face the outer peripheral portion.
[0032]
Although not specifically shown, the Hall ICs 20A and 20B are configured integrally with a Hall element and an amplifier circuit for amplifying a detection signal output from the Hall element. When the magnet 19 rotates as the motor 7 rotates, a rectangular wave pulse signal having a duty of about 50% is output according to the change in the magnetic pole. The Hall ICs 20A and 20B are arranged in a positional relationship such that the phase difference between the pulse signals differs by 90 degrees. That is, the magnet 19 and the Hall ICs 20A and 20B constitute an encoder (pulse generating means) 21.
[0033]
The two-phase (A, B) pulse signal output from the encoder 21 is supplied to a pulse conversion circuit (pulse conversion means) 22 and an up-count pulse signal (UP) and a down-count pulse signal according to a change in their phase relationship. (DOWN) and output to the counter 23.
[0034]
Here, FIG. 5 shows the output state of the two-phase pulse signal and the output state of the up / down count pulse signal output from the pulse conversion circuit 22 accordingly. As shown in the first half of FIGS. 5A and 5B, if the B-phase signal is delayed by 90 degrees from the A-phase signal when the motor 7 rotates forward, as shown in the latter half thereof, When the motor 7 rotates in the reverse direction, the phase of the B phase signal is advanced by 90 degrees with respect to the phase A signal.
[0035]
When the motor 7 rotates forward according to the change in the phase relationship, the pulse conversion circuit 22 generates and outputs an up-count pulse signal (see FIG. 5C), and the motor 7 rotates reversely. In this case, a down-count pulse signal is generated and output (see FIG. 5D). Specifically, for example, at the rising edge of the B-phase signal, the level of the A-phase signal is determined to be high or low.
[0036]
The counter (counting means) 23 performs an up-count operation when the pulse conversion circuit 22 outputs an up-count pulse signal, and performs a down-count operation when it outputs a down-count pulse signal (see FIG. 5E). The counter 23 clears the count value to zero when the upper limit position detection signal from the limit switch 12 is given.
[0037]
The count value of the counter 23 is given to a motor control circuit (control means) 24 composed of a microcomputer. The motor control circuit 24 is supplied with an ascending command signal and a descending command signal by switching the up / down switch 5 and also receives a slack detection signal by the slack detecting mechanism 13. The motor control circuit 24 controls the forward / reverse rotation of the motor 7 by switching the connection relationship between the commercial AC power supply 3 and a winding (not shown) of the motor 7 in accordance with the output of the up command signal and the down command signal. .
[0038]
The commercial AC power supply 3 is supplied to a power supply circuit 25. The power supply circuit 25 generates a control power supply for rectifying and lowering the AC power supply and stepping down the AC power supply to supply it to the motor control circuit 24 and the like. The control power generated and output by the power supply circuit 25 is also supplied to a power cutoff detection circuit (power cutoff detection means) 26. The power cutoff detection circuit 26 outputs an interrupt signal to the motor control circuit 24 when the commercial AC power supply 3 has lost power or when the control power supply has started to decrease due to the operation of the breaker 4. It has become.
[0039]
The motor control circuit 24 is connected to a storage circuit (storage means) 27 composed of, for example, an EEPROM. The storage circuit 27 stores the initial value of the maximum descending position of the lighting fixture 2, that is, the lower limit position (count value corresponding to). Then, when the interrupt signal is output, the motor control circuit 24 reads the count value of the counter 23 at that time, and writes and stores the count value in the storage circuit 27.
[0040]
Next, the operation of the present embodiment will be described with reference to FIGS. FIG. 6 is a flowchart showing the control executed by the motor control circuit 24. First, the motor control circuit 24 determines whether or not a power-off flag described later is set in a flag storage area of the storage circuit 27 (step S01), and if the flag is not set ("NO"), Move to S1.
[0041]
Then, the motor control circuit 24 is on standby until the elevation switch 5 is switched by the user and a downward command or an upward command is given (steps S1 and S15). When a descending command is given in this state (step S1, "YES"), a reset counter RC, which will be described later, is cleared to zero (step S2), and the motor 7 is rotated forward (step S3). Then, since pulse conversion circuit 22 outputs an up-count pulse signal, counter 23 performs an up-count operation.
[0042]
Then, the motor control circuit 24 determines whether or not the count value of the counter 23 has exceeded the lower limit position stored in the storage circuit 27 (step S4). If the wire rope 8 is not at or above the lower limit position ("NO"), the looseness detection mechanism 13 detects that the wire rope 8 has been loosened (step S8), or the lift switch 5 has been returned to the stop position (output of a descending command). Is stopped) (step S9).
[0043]
If the count value of the counter 23 is equal to or greater than the lower limit position (step S4, "YES") while the loop of steps S4, S8, and S9 is being performed, the motor control circuit 24 stops the motor 7 from lowering (step S4). S5). Then, for example, it is determined with reference to a flag storage area such as a RAM incorporated in the control circuit 24 whether or not an intermediate stop flag described later is set (step S6). If the halfway stop flag is not set ("NO"), the process returns to step S1.
[0044]
In addition, in the state where the lighting fixture 2 is in contact with some object while the loop of steps S4, S8, and S9 is being rotated, or when the user's hand supports the lighting fixture 2 and is prevented from descending, When the slack detection mechanism 13 detects the slack of the wire rope 8 (Step S8, "YES"), the motor control circuit 24 stops the lowering of the motor 7 (Step S13). Then, the count value of the counter 23 at that time is read, and the count value is written and stored in the storage circuit 27 as a new lower limit position (step S14). Then, the process returns to step S1.
[0045]
That is, in this case, due to the structure of the house where the lighting fixture 2 is disposed, the lighting fixture 2 is excessively lowered at the initially set lower limit position, which is inappropriate, or the user sets the lower limit position. Is determined to be desired to be installed at a higher position, and the lower limit position is updated to the position where the lighting fixture 2 has stopped.
[0046]
Further, if the user operates the up / down switch 5 to return to the stop position while the loop of steps S4, S8, and S9 is being rotated (step S9, “YES”), the motor control circuit 24 also controls the motor 7 The descent is stopped (step S10). Then, the count value of the counter 23 at that time is read, and the count value corresponding to the stop position is temporarily written and stored in an internal RAM or the like (step S11). Then, when the midway stop flag is set in the flag storage area (step S12), the process returns to step S1.
[0047]
That is, at this time, it is impossible to determine whether the user has temporarily stopped the descent of the lighting fixture 2 halfway or stopped with the intention of setting the stop position at that time as the lower limit position. In step S11, only the count value corresponding to the stop position is temporarily stored.
[0048]
On the other hand, when the ascending command is given while the loop of steps S1 and S15 is running (step S15, “YES”), the motor control circuit 24 determines whether the count value of the counter 23 is “0”, that is, It is determined whether the lighting fixture 2 is at the upper limit position (step S16). If the count value is not "0"("NO"), the reset counter RC is also cleared to zero (step S17), and the motor 7 is rotated reversely (step S18). Then, the pulse conversion circuit 22 outputs a down-count pulse signal, so that the counter 23 performs a down-count operation.
[0049]
Then, the motor control circuit 24 determines whether or not the count value of the counter 23 has become "0" (step S19) and whether or not the user has returned the elevating switch 5 to the stop position (step S20). . When the count value reaches "0" (step S19, "YES"), the process proceeds to steps S5 and S6.
[0050]
In step S6, if the halfway stop flag is set due to execution of step S12 ("YES"), the motor control circuit 24 sets the halfway stop position temporarily stored in step S11 as the lower limit position in the storage circuit 27. Is written and stored (step S7). Then, when the halfway stop flag is reset (step S7a), the process returns to step S1.
[0051]
That is, when the user operates the elevating switch 5 with the intention of setting the halfway stop position as the lower limit position and stops the lowering of the lighting fixture 2 halfway, thereafter, the lighting fixture 2 is raised to the upper limit position. This is determined in advance as a setting procedure.
[0052]
Also, when the user operates the elevating switch 5 to switch to “stop” while the lighting fixture 2 is rising (Step S20, “YES”), the motor control circuit 24 stops the rising of the lighting fixture 2 (Step S21). ). Then, the midway stop flag is reset (step S21a), and the process returns to step S1. That is, in this case, since the lighting fixture 2 has not been raised to the upper limit position, it is determined that the user does not intend to set the halfway stop position as the lower limit position.
[0053]
Further, when the user operates the elevating switch 5 to give an ascending command (step S15, "YES"), it is assumed that the count value of the counter 23 is "0", that is, the lighting fixture 2 is at the upper limit position. (Step S16, "YES"). In this case, the motor control circuit 24 increments the reset counter RC (software counter) (step S22), and determines whether the count value of the counter RC has reached "3" (a predetermined number of times) (step S22). S23). If the count value has not reached "3"("NO"), the process returns to step S1, and if the count value has reached "3"("YES"), the value is stored in the storage circuit 27 at that time. The lower limit position is initialized (step S24). Then, the process returns to step S1.
[0054]
That is, even if the lighting device 2 is already at the upper limit position, if the elevating switch 5 is continuously operated to “up” three times by the user, the lower limit position updated by the halfway stop position is initialized. Procedure for this.
[0055]
FIG. 7 is a flowchart showing the contents of an interrupt process performed by the motor control circuit 24 when the power cut-off detection circuit 26 detects that the commercial AC power supply 3 has been cut off. In this case, if the motor 7 is being driven, the motor control circuit 24 stops the driving (step S31). Then, when the count value of the counter 23 at that time is read, it is written and stored in the storage circuit 27 (step S32). Then, a power cutoff flag is set in the storage circuit 27 (step S33).
[0056]
When the power cutoff flag is set in the storage circuit 27 in this way, the commercial AC power supply 3 is restored, and when the motor control circuit 24 starts executing the flowchart shown in FIG. 6 (start), the motor control circuit 24 In step S01, "YES" is determined, and in step S32, the count value of the counter 23 stored as the current position is read (step S02). When the power shutdown flag is reset (step S03), the process proceeds to step S1.
[0057]
That is, even when the commercial AC power supply 3 is cut off, the count value of the counter 23 corresponding to the current position of the lighting fixture 2 at that time is stored in the storage circuit 27 and read out when the power supply is restored, so that the motor control circuit 24 The current position can be grasped.
[0058]
As described above, according to the present embodiment, the motor control circuit 24 of the electric lifting device 1 drives the motor 7 to rotate the winding drum 9, and lowers the lighting fixture 2 suspended by the wire rope 8. In this case, when the count value of the counter 23 that counts the pulse signals output from the encoder 21 reaches a predetermined value indicating the lower limit position, the driving of the motor 7 is stopped.
[0059]
Therefore, the motor control circuit 24 can grasp the descending position of the lighting fixture 2 based on the pulse signal output from the encoder 21, and can stop the lighting fixture 2 accurately at the lower limit position. In particular, when a plurality of lighting fixtures 2 are controlled simultaneously as shown in FIG. 2, it is possible to make the stop positions thereof as uniform as possible. Then, the height position of the lighting fixture 2 configured to be hung from the ceiling in the house can be controlled, and even in the case of a house having a considerably high ceiling (for example, a factory or a gymnasium). For example, when the light bulb of the lighting fixture 2 burns out, the light bulb can be easily replaced.
[0060]
Further, the encoder 21 is connected to the motor 7 by two Hall ICs 20A and 20B arranged so that the phase difference between the two-phase pulse signals output to the magnet 19 attached to the rotating shaft of the motor 7 becomes 90 degrees. The pulse conversion circuit 22 is configured to output a two-phase pulse signal having a different phase relationship in accordance with the forward / reverse rotation of the signal, and to generate and output an up / down count pulse signal in accordance with the phase relationship.
[0061]
Therefore, the pulse conversion circuit 22 determines the rotation direction of the motor 7, that is, the rise and fall of the lighting fixture 2, by detecting the change in the delay and the advance of the phase difference of 90 degrees between the two-phase pulse signals. An up-count pulse signal and a down-count pulse signal can be output. Then, even when the wire rope 8 is wound by the winding drum 9 and the lighting fixture 2 rises, the motor control circuit 24 can grasp the position thereof, and the lowering operation and the raising operation are intermittently repeated. In this case, the position of the lighting fixture 2 can be accurately grasped.
[0062]
Furthermore, the limit switch 12 detects that the lighting fixture 2 has reached the upper limit position, and the counter 23 is set so that the count value is set to the initial value when the detection signal is output. The probability of occurrence can be reduced.
[0063]
Further, when the slack detection mechanism 13 detects the slack of the wire rope 8 while the lighting fixture 2 is being lowered, the motor control circuit 24 sets the count value indicated by the counter 23 at that time as the lower limit position. did. Accordingly, when the lighting fixture 2 is prevented from descending due to contact with an object, or when the user intends to set the lower limit above the initially set lower limit, the lighting during the lowering is intended. For example, when the device 2 is controlled by hand, the position can be set as the lower limit position.
[0064]
When the power cutoff detection circuit 26 detects that the commercial AC power supply 3 has been cut off, the motor control circuit 24 stores the count value of the counter 23 in the storage circuit 27, and stores the stored count value when the power supply is restored. The current position is read out. Therefore, when returning after the power is turned off, the motor control circuit 24 can grasp the current position of the lighting fixture 2 and continue the elevation control.
[0065]
Further, before the lighting fixture 2 being lowered reaches the lower limit position set as the initial value, the motor control circuit 24 stops the lowering operation by the user operating the raising / lowering switch 5 and thereafter performs the raising operation. When the lighting fixture 2 reaches the upper limit position after turning to, the stop position at the time of the descending operation is set as the lower limit position, so that the user can set a desired lower limit position by executing the above procedure.
[0066]
In addition, when the user operates the elevating switch 5 and performs the “elevation” operation three times in a state in which the lighting fixture 2 is at the upper limit position, the motor control circuit 24 clears the lower limit position set by the user and initializes the initial position. Since the lower limit position is reset, the lower limit position can be set and initialized only by the lifting switch 5.
[0067]
The present invention is not limited to the embodiment described above and shown in the drawings, and the following modifications or extensions are possible.
Although the number of magnetizations of the magnet 19 is two poles, the number of poles may be a multiple of two.
Instead of the encoder 21, the pulse generating means may be constituted by a combination of a slit disk and a photo interrupter, or a combination of a gear and an MR element.
Instead of the commercial AC power supply 3, the power supply circuit 25 may be supplied with power after passing through the breaker 4 and the elevating switch 5.
The predetermined number of times for initializing the lower limit position is not limited to “3” and may be set as appropriate.
The pulse conversion circuit 22, the counter 23, the power cutoff detection circuit 26, the storage circuit 27, and the like may be configured as a microcomputer integrated with the motor control circuit 24.
[0068]
The motor control circuit 24 is configured to clear the lower limit position set by the user and return to the initial value when the slack of the wire rope 8 is detected when the count value of the counter 23 indicates the lower limit position. May be. With this configuration, if the user lifts the lighting fixture 2 at the lower limit position slightly, for example, by hand, the wire rope 8 is slackened and the lower limit position can be initialized.
When the slack of the wire rope 8 is detected while the lighting apparatus 2 is being lowered, the motor control circuit 24 sets the count value corresponding to a position slightly higher than the count value indicated by the counter 23 at that time. May be set as the lower limit position. For example, if the lighting fixture 2 is blocked by the lighting fixture 2 coming into contact with an object before the lighting fixture 2 is being lowered, that is, before reaching the lower limit position set initially, If the position slightly higher than the count value is set as the lower limit position, it is possible to avoid contact with the object when the lighting fixture 2 is lowered thereafter.
[0069]
The pulse generation means is not necessarily limited to a configuration for outputting a two-phase pulse signal, and a pulse conversion means may be provided as needed. For example, only the lowering position of the lighting fixture 2 may be controlled. In that case, the counting means may perform only one of up-counting and down-counting.
The rope is not limited to the wire rope 8, but has a tensile strength such that the elongation due to its weight falls within an allowable range when the electric device is hung, and an elasticity that does not hinder winding by the winding drum. Other materials may be used as long as they are provided.
The slack detecting means may be provided as needed.
The power cutoff detecting means may be provided as needed.
The case where there is only one set of the electric lifting device 1 and the lighting fixture 2 may be used.
The electric device is not limited to the lighting device 2 and may be a speaker or the like.
[0070]
【The invention's effect】
According to the electric lifting device for electric equipment of the present invention, the control means drives the motor to rotate the winding drum, and when the electric equipment suspended by the rope is lowered, the control means controls the rotation of the motor. When the count value of the counting means that performs a counting operation based on the pulse signal generated by the pulse generating means reaches a predetermined value indicating the lower limit position, the driving of the motor is stopped. Therefore, the control means can grasp the descending position of the electric equipment based on the pulse signal, and stop the driving of the motor when the count value of the counting means reaches the predetermined value, thereby lowering the electric equipment at the lower limit. It is possible to stop accurately at the position.
[Brief description of the drawings]
FIG. 1 is an example in which the present invention is applied to a lighting fixture, and is a functional block diagram showing an electrical configuration of a lifting device.
FIG. 2 is a diagram showing an overall configuration.
FIG. 3 is a diagram showing a configuration centered on an electric lifting device.
FIG. 4A shows a state of the slack detection mechanism when a constant tension is acting on the wire rope, and FIG. 4B shows a state of the slack detection mechanism when the tension is weakened.
FIG. 5 is a diagram illustrating an output state of a two-phase pulse signal by an encoder and an output state of an up / down count pulse signal output by a pulse conversion circuit in response thereto.
FIG. 6 is a flowchart illustrating control executed by a motor control circuit;
FIG. 7 is a flowchart showing the contents of an interrupt process performed by the motor control circuit when the power cutoff detection circuit detects that the commercial AC power has been cut off;
[Explanation of symbols]
1 is an electric lifting device, 2 is a lighting device (electric device), 3 is a commercial AC power supply, 5 is a lifting switch, 7 is an AC motor, 8 is a wire rope, 9 is a winding drum, and 12 is a limit switch (upper limit position detection). Means, 13 is a slack detecting mechanism (loose detecting means), 19 is a magnet (disc magnet), 20A and 20B are Hall ICs (Hall elements), 21 is an encoder (pulse generating means), 22 is a pulse conversion circuit (pulse). Conversion means), 23 a counter (counting means), 24 a motor control circuit (control means), 26 a power cutoff detection circuit (power cutoff detection means), and 27 a storage circuit (storage means).

Claims (8)

A rope connected to an electric device at a tip thereof, a winding drum for winding the rope, and a motor for rotating the winding drum.
Pulse generating means attached to the motor, for outputting a pulse signal with rotation of the motor,
Counting means for performing a counting operation based on the output state of the pulse signal, and when the electric device is lowered by driving the motor, when a count value of the counting means reaches a predetermined value indicating a lower limit position. Control means for controlling so as to stop the driving of the motor. The pulse generating means is configured to output a two-phase pulse signal having a different phase relationship according to the forward / reverse rotation of the motor,
Pulse conversion means for converting the two-phase pulse signal into an up-count pulse signal and a down-count pulse signal according to the phase relationship and outputting the converted signal;
2. The electric lifting and lowering device for electric equipment according to claim 1, wherein the counting means is configured to perform an up / down counting operation based on an output state of the up count pulse signal and the down count pulse signal. The pulse generating means includes a disk-shaped magnet attached to the rotating shaft of the motor and magnetized to n poles (n is a multiple of 2), and a phase difference of a two-phase pulse signal output from the disk-shaped magnet. 3. The electric lifting and lowering device for electric equipment according to claim 2, comprising two Hall elements arranged at 90 degrees. An upper limit position detecting unit that detects that the electric device has reached the upper limit position and outputs a detection signal,
4. The electric lifting and lowering device for an electric device according to claim 1, wherein the counting unit is configured to set a count value to an initial value when the detection signal is output. Equipped with slack detection means for detecting slack of the rope,
5. The control device according to claim 1, wherein when the slack is detected while the electric device is being lowered, the count value indicated by the counting device at that time is set as a lower limit position. 6. An electric hoisting and lowering device for an electric device according to claim 1. 6. The control unit according to claim 5, wherein, when the slack is detected when the count value of the counting unit indicates the set lower limit position, the control unit clears the lower limit position and returns to the initial value. Electric lifting device for electrical equipment. Power cutoff detecting means for detecting that the power supply has been cut off, wherein the control means stores the count value of the count means in a storage means when the cutoff of the power supply is detected, and stores the count value when the power supply is restored. 7. The electric lifting and lowering device for an electric device according to claim 1, wherein the count value stored in the electronic device is read out and set as a current position. The electric lifting device for an electric device according to claim 1, wherein the electric device is a lighting fixture.

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