JP2003102562A - Motor-driven moving shelf - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a motor-driven moving shelf in which the motor-driven moving shelf using a DC motor as a driving source is improved and safety is improved so as to rapidly stop it when urgent stopping is necessary and an enough vibration-dampening effect can be obtained when an earthquake is generated. SOLUTION: The DC motor 52 for moving back and forth the moving shelf by positively and reversely rotating running wheels and a control circuit 50 for positively and reversely rotating and driving the DC motor 52 by operating operation switches 4 and 6 are provided and when a passage entering sensor 58 outputs a detecting signal while the moving shelf is moved and when foreign substance detecting sensors 61, 62, 63 and 64 output detecting signals, the control circuit 50 makes the DC motor 52 function as an electric power generating brake to rapidly stop the moving shelf. After being stopped, the electric power generating brake is released to give an vibration dampening effect. When it functions as the electric power generating brake and a vibration sensing means perceives an earthquake, the control circuit 50 releases the function for the electric power generating brake.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric mobile shelf using a DC motor as a drive source, and more particularly, to enhance safety and seismic isolation effect by utilizing the characteristics of the DC motor as a drive source. It relates to an electric mobile shelf.

[0002]

2. Description of the Related Art An electric movable rack containing a heavy object can be moved by inertia once it starts moving, simply by stopping the power supply to a motor as a drive source. Therefore, the movement distance by inertia is shortened as much as possible. Therefore, the brake device is installed. An alternating current (AC) motor, for example, a capacitor-type reversible single-phase induction motor is used as a drive source in a conventional electric mobile rack. Due to its characteristic, the AC motor cannot be stopped immediately even if the power supply is stopped.
Therefore, if an AC motor is used as a drive source for an electric movable rack that requires forward / reverse control, the traveling direction cannot be switched immediately.

Therefore, a conventional electric movable rack using an AC motor as a drive source is equipped with a simple brake device for applying a mechanical braking force at the time of stop, and when the power supply to the motor is stopped, the speed is as fast as possible. It has been devised to stop at.

Further, as a characteristic of the AC motor, the number of revolutions and the output torque are directly proportional to each other, so that a predetermined torque is not generated unless the revolution speed rises and the traveling speed becomes constant. Therefore, in order to obtain a predetermined torque, increase the rotation speed of the motor and
It is necessary to increase the reduction ratio of the power transmission mechanism from the output shaft of the motor to the drive wheel shaft to compensate for the torque shortage. When the rotation speed is increased, inertial force increases the stopping distance of the movable rack. Such characteristics of the AC motor require a larger torque when starting to move, and are not suitable as a drive source for a moving rack that requires a small torque after starting.

When the reduction ratio of the power transmission mechanism is increased as described above, the resistance force when looking at the power transmission system from the traveling wheel side to the motor increases. Therefore, it is substantially the same as the case where the braking force is constantly applied, and it is possible to recognize the advantage in that it is difficult to start moving indefinitely in the stopped state and the stopped position is stably maintained. However, if the resistance seen from the running wheel side is large, the seismic energy at the time of an earthquake is transmitted to the moving rack via the power transmission mechanism, and the moving rack shakes greatly, causing the stored items to fall or drop. The shelf itself may fall. In order to eliminate such inconvenience, it is considered that an electromagnetic clutch is provided in the power transmission mechanism and the clutch is disengaged by a seismic signal from the seismic means so that seismic energy is not transmitted to the moving rack. . However, the cost of the electromagnetic clutch is not so different from the cost of the AC motor, and the cost is high.

Further, if the reduction ratio of the power transmission mechanism is increased as described above, even if an attempt is made to manually move the movable rack in the event of a power failure, the resistance force applied to the power transmission mechanism is large and it is difficult to move. is there.

As described above, in the conventional electric type moving rack using the AC motor, the moving speed of the moving rack is slow because the reduction ratio is increased even if the rotation speed of the motor is increased.
Another problem is that it takes a long time to form a work passage having a predetermined size between the movable shelves. On the other hand, although the torque of the AC motor is sufficient after the start of the moving rack, the torque of the AC motor increases with the increase of the rotation speed, so that the surplus torque is finally integrated. The movable rack may be skewed due to a biased load due to the bias of the stored items.
Alternatively, the guide rail may be skewed or meandered due to the inclination or bending of the guide rail. If the movable rack skews or meanders in the state where the surplus torque is integrated as described above, there arises a problem that the wheels run on the rails or the flanges of the wheels and the rails are strongly hit and both are scraped.

As described above, since the AC motor is not suitable for the drive source of the electric mobile rack, the applicant has proposed to use the DC motor as the drive source of the electric mobile rack. The invention described in the specification and drawings of Japanese Patent Application No. 2000-327067 is one of them. The DC motor is
It has the characteristic that the maximum torque is obtained at startup, that is, when the rotation speed is zero, and the torque decreases as the rotation speed increases. The DC rack motor is suitable as a drive source for the electric mobile rack because the mobile rack requires maximum torque at the time of start-up and a small torque is sufficient when it starts to move. Since there is no excess torque after starting, the wheels do not ride on the rails, and the flanges of the wheels and the rails do not come into contact with each other with a strong force.

Further, in the electric type moving rack which employs the DC motor as the drive source, since a sufficient starting torque can be obtained, it is possible to push and move a plurality of other moving racks by one moving rack. As described in the specification and the drawing of Japanese Patent Application No. 2000-327067, the electric mobile rack can be configured with a simple circuit.

In addition to the above-mentioned advantages, the electric mobile rack using the DC motor as the drive source has the following advantages.・
Since the reduction gear ratio can be reduced, the moving speed of the movable rack is high, and the work passage having a predetermined width can be quickly formed. -Since the reduction ratio can be reduced, the load seen from the traveling wheel side can be reduced, and the mobile rack can be moved by manual force as needed when a power failure occurs. Further, the driving efficiency is improved by about 30%. -Since the reduction ratio can be reduced, the seismic isolation effect can be obtained without providing an electromagnetic clutch in the drive system, and an electric seismic isolation mobile shelf can be constructed at low cost.

[0011]

SUMMARY OF THE INVENTION The present invention has further improved an electric movable rack using a DC motor as a drive source, which has many advantages as described above, and it is necessary to stop the rack in normal operation or in an emergency. It is an object of the present invention to provide an electric mobile rack that can be quickly stopped at certain times to enhance safety and, when an earthquake occurs, a sufficient seismic isolation effect can be obtained.

[0012]

In order to achieve the above-mentioned object, the invention according to claim 1 has a traveling wheel, a direct current motor for reciprocally rotating the traveling wheel to reciprocate a movable rack, and an operation. A control circuit for driving a direct-current motor to rotate forward and backward by operating a switch, wherein the control circuit causes the direct-current motor to function as a dynamic brake when the mobile shelf stops. The power generation brake may be immediately released by stopping the moving rack.
As in the invention described above, the power-generating brake may be released after a certain period of time has passed after the movable rack was stopped. When the mobile rack is stopped, it can be stopped quickly by making the DC motor function as a dynamic brake. After stopping, releasing the power-generating brake allows the running wheels to rotate and provides a seismic isolation effect.

According to a third aspect of the present invention, there are provided a traveling wheel, a DC motor for rotating the traveling wheel in the normal and reverse directions to reciprocate the movable rack, and a control circuit for driving the DC motor in the forward and reverse directions by operating an operation switch. A plurality of electric mobile shelves are arranged so that they can be converged and separated, and each of the electric mobile shelves is equipped with a passage entry sensor that detects when a person enters an aisle formed between the mobile shelves. The circuit makes the DC motors of all the moving shelves function as generator brakes when the aisle entry sensor outputs a detection signal, and also the DC motors of all the moving shelves generate a brake until the passage entry sensor stops outputting the detection signal. It is characterized by making it function as. When a passage entry sensor outputs a detection signal due to a person entering the passage between the movable shelves, the DC motors of all the movable shelves are braked until the output of the detection signal is stopped.

According to a fourth aspect of the present invention, when the aisle entry sensors output detection signals while the mobile shelves are moving, the DC motors of all the mobile shelves function as power-generating brakes, and the aisle entry sensors output the detection signals. The feature is that the DC motors of all the moving shelves are made to function as a dynamic brake until the output is stopped. When the passage entry sensor outputs a detection signal, the DC motors of all the moving shelves are subject to power generation braking, and the moving shelves that are moving quickly stop. Until the output of this detection signal is stopped, the DC brakes of all the moving shelves are subject to power generation braking.

According to a fifth aspect of the present invention, there are provided a traveling wheel, a DC motor for rotating the traveling wheel in the forward and reverse directions to reciprocate the movable rack, and a control circuit for driving the DC motor in the forward and reverse directions by operating an operation switch. A plurality of electric mobile shelves are arranged so that they can be converged and separated, and a foreign matter detection sensor that detects when a person or other foreign matter comes into contact with the article loading / unloading surface of each mobile rack is provided. The control circuit causes the DC motors of all the moving shelves to function as power-generating brakes when the foreign matter detection sensor outputs a detection signal while the moving shelves are moving, and causes the moving shelves to be stopped in an emergency. It is characterized in that the DC motors of all the moving shelves function as power-generating brakes until the output of the detection signal is stopped by. When a foreign object detection sensor outputs a detection signal due to a person entering the passage between the mobile shelves, the DC motors of all the mobile shelves are braked until the output of the detection signal is stopped.

According to a sixth aspect of the present invention, in the invention according to any one of the first to fifth aspects, there is provided seismic sensing means, and when the seismic sensing means senses an earthquake with a certain seismic intensity or more, a control circuit is provided. Is to release the function of the DC motor as a power generation brake. When an earthquake occurs, the control circuit cancels the function of the DC motor as a dynamic brake.
The running wheels rotate due to the shaking of the floor surface due to the earthquake, and the transmission of seismic energy to the moving shelves is blocked, so that the seismic isolation function is exerted.

According to a seventh aspect of the present invention, in the invention according to any one of the first to fifth aspects, there is provided seismic sensing means, and when the seismic sensing means senses an earthquake having a certain seismic intensity or higher, a control circuit is provided. Is to release the function as a dynamic brake of the DC motor by cutting off the power supply. When an earthquake occurs, the control circuit cuts off the power supply to release the function of the DC motor as a power generation brake, and the mobile shelf can obtain a seismic isolation effect.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an electric mobile shelf according to the present invention will be described below with reference to the drawings. In FIGS. 2 and 13, reference numeral 2 indicates a movable rack. In the example shown in FIG. 2, four movable shelves 2 are movably arranged and arranged so that they can be aggregated separately. Each of these movable shelves 2 has traveling wheels 8 at the bottom in the traveling direction, and
It has a motor 52 that rotationally drives each traveling wheel 8. The traveling wheels 8 rotate on rails laid on the floor, and the movable shelves 2 can be moved by being guided by the rails.

In the example shown in FIG. 2, the front surface of each movable rack, that is, the article loading / unloading surface is oriented in a direction perpendicular to the paper surface,
Each mobile shelf is at right angles to the front (left and right parallel to the paper)
To move to. In the present specification, the front surface of each movable shelf (the loading / unloading surface of articles) is referred to as the right side surface or the left side surface, and the vertical surface that is perpendicular to the front surface and on which the operation portion appears as shown in FIG. 2 is called the front surface. .

A motor 52 which is a drive source for each of the movable shelves described above.
Is a direct-current motor having a characteristic that maximum torque can be obtained at the time of start-up, and rotates forward and reverse by switching the polarity of the direct-current power supply that is supplied. It can be moved back and forth. Each movable rack 2 is provided with operation switches 4 and 6 on both sides in the moving direction. In the illustrated example, a side panel is attached to the front of each movable shelf 2,
Operation switches 4 and 6 are provided at the front and rear ends of the side panel in the traveling direction of the movable rack. Operation switch 4
Is a rightward operation switch that is pushed toward the right side when the movable shelf 2 is moved to the right side, and is provided on the left side of the side panel. The operation switch 6 is a leftward operation switch that is pushed toward the left side when the movable shelf 2 is moved to the left side, and is provided on the right side of the side panel.

As shown in FIG. 13, an underframe safety bar 62, which is a first foreign matter detection sensor, is attached horizontally to the front surface of the bottom underframe of each movable shelf 2. Although only the right frame safety bar 62 is shown in FIG. 13, the left frame safety bar is also attached to the left surface. A passage safety bar 64, which serves as a second foreign matter detection sensor in the horizontal direction, is attached to the front surface of the shelf having an appropriate height on the front surface of each movable shelf 2. The underframe safety bar 62 touches a foreign object in the passage between the moving shelves and the feet of the worker, or the worker passes the passage safety bar 6
When touched by 4, the switches of the safety bars are operated to output a detection signal.

As shown in FIG. 13, an emergency switch 56 is attached to the side panel of each movable rack 2 for moving the movable rack after the emergency stop of the movable rack. Further, a passage entry sensor 58 is attached to the side panel of each movable rack 2 on the front side of the movable rack. The passage entry sensor 58 shown in FIG. 13 is of an optical type and is configured by arranging a light emitting element on one of adjacent moving shelves and arranging a light receiving element emitted from this light emitting element on the other moving shelf.
When a person enters the passage, the light beam is blocked to detect that the person has entered the passage.

Next, an example of an electric circuit built in each movable rack 2 will be described with reference to FIG. In FIG. 1, reference numeral 50 indicates a control circuit for controlling the forward / reverse rotation, stop and braking operations of the DC motor 52, which is composed of a microcomputer (hereinafter referred to as “microcomputer”). Control circuit 5 by converting commercial AC power supply to DC 24V
It has a stabilized DC power supply 53 which is supplied to 0 as a power supply. The control circuit 50 has, as input means, a rightward operation switch 4, a leftward operation switch 6, an underframe safety bar left switch 61, an underframe safety bar right switch 62, an aisle safety bar left switch 63, and an aisle safety bar right switch. 64 and the emergency switch 56 are connected. Further, when an earthquake with a certain seismic intensity or more occurs, it is sensed and outputs a signal, and a passage entry sensor 58 that detects when a person enters a work passage formed between the movable shelves. Are connected.

The underframe safety bar left switch 61 and the underframe safety bar right switch 62 are, as described above, safety bar switches that function as foreign matter detection sensors and are arranged on the front surface of the underframe. The aisle safety bar left switch 63 and the aisle safety bar right switch 64 are safety bar switches that function as foreign matter detection sensors, as described above, and are arranged on the front surface of the shelf board at appropriate heights. When the underframe safety bar left switch 61 or the aisle safety bar left switch 63 operates, the left safety bar operating lamp 66 flashes, and when the underframe safety bar right switch 62 or the aisle safety bar right switch 64 operates, The right-side safety bar operation lamp 65 flashes to indicate that the movable rack cannot be moved. When these safety bar switches are restored, the lamps 65 and 66 are turned off.

By the operation of each of the safety bar switches constituting the foreign matter detection sensor, the passage entry sensor 58 is also operated.
As will be described later in detail, the DC operation of all the moving shelves applies the power generation brake, so that the moving shelves are quickly stopped and interlocked. Further, even if the safety devices such as the safety bar switch and the passage entry sensor 58 fail, the interlock is provided. As described above, when the interlock is applied, the movable rack cannot be moved only by operating the operation switches 4 and 6. Therefore, by operating the rightward operation switch 4 or the leftward operation switch 6 with the emergency switch 56 being operated, the movable rack can be moved to the right or left. Since the movable rack can be moved only by operating the operation switch in this state on condition that the emergency switch 56 is operated, careful operation is performed and safety can be improved.

The control circuit 50 is connected to the above-mentioned DC motor 52 to be controlled, and is also connected to a right side safety bar operating lamp 65 and a left side safety bar operating lamp 66. The control circuit 50 drives the DC motor 52 to rotate forward and backward while the right going signal and the left going signal are input, and stops the driving of the DC motor 52 by stopping the right going signal and the left going signal, and the DC motor 52. The power generation brake is applied to 52. The control circuit 50 also receives a detection signal from a passage entry sensor, a detection signal from a foreign object detection sensor including an underframe safety bar or an aisle safety bar, or detects a passage entry sensor, an underframe safety bar, an aisle safety bar, or the like. It also includes a drive circuit that applies a dynamic brake to the DC motor 52 if the safety device fails.

The control circuit 50 controls the drive circuit by operating the rightward operation switch 4, and drives the DC motor 52 so that the movable rack 2 moves to the right,
At the same time, a rightward signal is output.
This rightward signal is introduced to the mobile shelf 2 adjacent to the right side through the right truck communication line. Further, the control circuit 50 controls the drive circuit by operating the leftward operation switch 6, drives the DC motor 52 so that the movable rack 2 moves leftward, and simultaneously outputs a leftward signal. It is like this. The leftward signal is introduced to the mobile shelf 2 adjacent to the left side through the left truck communication line.

The control circuit 50 also controls the drive circuit when a left-going signal is input from the mobile shelf on the right side through the right trolley communication line, and controls the DC motor 52 so that the mobile shelf 2 moves to the left. While driving, it outputs a left-going signal and transmits it to the moving shelf on the left side through the left truck communication line.
Similarly, when a rightward signal is input from the moving shelf on the left side through the left truck communication line, the control circuit 50 controls the drive circuit to drive the DC motor 52 so that the moving shelf 2 moves rightward. At the same time, it outputs a rightward signal and transmits it to the moving shelf on the right side through the right trolley communication line.

When the rightward operation switch 4 or the leftward operation switch 6 of the movable rack 2 is operated, the control circuit 50 operates so that the DC motor 52 of the movable rack 2 is operated at the rated output. Control the drive circuit. On the other hand, when a right-going signal or a left-going signal is input from another mobile rack, the control circuit 50 causes the DC motor 52 of the mobile rack 2 to input the right-hand operation switch 4 or the left-hand operation switch 6 to the DC motor 52. The drive circuit is controlled so that electric power less than the electric power supplied to the motor of the operated moving rack is supplied, for example, the electric power that cannot move the moving rack 2 by itself. If the rated output of the DC motor 52 is obtained by supplying a current of 8 A at 24 V, for example, the electric power of the movable rack 2 that cannot move by itself supplies a current of about 6 A at 24 V. Can be obtained by doing.

A control circuit 50 built in each mobile shelf 2.
In the above drive circuit, a power generation brake circuit for generating an electric braking force when the movement of the movable rack is stopped is incorporated. FIG. 3 shows an example of the dynamic braking circuit. In FIG. 3, as described above, a drive circuit included in the control circuit 50 supplies a drive current in the forward and reverse directions between the terminals of the DC motor 52, so that the DC motor 52 is driven to rotate in the forward and reverse directions. ing. In addition, a switch 20 that short-circuits the terminals is connected between the terminals of the DC motor 52 as one of the power-generating brake circuits. Further, a switch 22 connecting the terminals is connected via a 2Ω resistor.
In addition, a switch 2 that connects the terminals via a 4Ω resistor.
4 is connected. Each switch 20, 22, 24 is
The control circuit 50 includes a relay switch or a thyristor which is turned on / off.

The sensing signal of the vibration sensing means 57 is the control circuit 5
0, the control circuit 50 is configured to release the dynamic braking function of the DC motor 52 by the input of the sensing signal. Specifically, by inputting a sensing signal, each switch 20, 22, 2 of the above-mentioned power generation brake circuit is
Turn off all 4 and release the generator brake. In this way, the traveling wheels rotate due to the shaking of the floor surface caused by the earthquake, so that the transmission of the seismic energy to the moving rack is interrupted, and the seismic isolation effect can be obtained.

The passage entry sensor 58 passes two light beams side by side on the front side and the back side, for example, across the entrance and exit to the working passage between the movable shelves, and the light beam on the front side is blocked and the light beam on the back side is blocked. It can be configured to detect the entry of a person into the passage when the light beam is blocked. Or 1
It may be configured to use only the light beam of the book and to consider that a person has entered the passage when the light beam is blocked.
A circuit having the same configuration as the circuit shown in FIGS. 1 and 3 described above is built in each movable rack 2.

The operation of the embodiment configured as described above will be described with reference to FIGS. 4, 5 and 6. Reference numerals such as “S1”, “S2”, and “S3” are attached to each operation step. FIG. 4 shows an example of the general operating procedure. In FIG. 4, it is judged based on the operator's judgment whether or not the aisles are displayed (S1). Then, it is judged whether or not there is danger even if the movable rack is driven next (S2), and if there is no danger, the operation switch is turned on (S3). The operation switch is either the rightward operation switch 4 or the leftward operation switch 6 described above. When the operation switch is turned on, the drive control of the motor 52 is performed, and the movable shelf travels to the right or left (S4). Details of this drive control will be described later.

Whether the safety device is activated during drive control,
That is, it is checked whether the left and right underframe safety bars 61, 63 or the left and right passage safety bars 63, 64 which are the foreign matter detection sensors described with reference to FIG. 1 have worked (S5). If the safety device does not work, the movable rack travels until the operation switch is turned off (S6), and the operation switch is turned off so that normal brake control is performed (S).
7). The normal brake control will be described later in detail. If the safety device is activated in S5, emergency brake control is performed (S8), and the emergency brake is applied to the moving rack. The emergency brake control will also be described later in detail. As described above, when the brake control is performed and the moving rack stops, immediately or 0.5 to 1.0 after the stop.
The power generation brake is released after about a second (S9).
It is possible to add a seismic isolation function to the mobile shelf by releasing the power generation brake. This is because the release of the power generation brake allows the traveling wheels to rotate with respect to the shaking of the floor surface during an earthquake, and reduces the transmission of seismic energy to the moving rack.

Details of the drive control will be described with reference to FIG. In FIG. 5, when the rightward or leftward operation switch is pressed to turn it on (S11), the current supplied to the motor 52 can be controlled to drive the motor 52 in the shelf where the operation switch is pressed. A current, for example 8 amps, is passed (S12). On the other hand, in the shelf pushed by the above shelf (hereinafter, referred to as "lower shelf by Digichain"), the current supplied to the motor 52 is controlled so that the motor for the shelf whose rightward or leftward operation switch is operated. A current that is less than the current supplied to 52, for example, a current that allows the motor 52 to drive the shelf in a short time (for example, 6 amps) is supplied. As a result, the motor 52 of the shelf whose operation switch is pressed rotates to the right or left, and the movable shelf moves to the right or left (S14).
Push other shelves located to the right or left.

The reason why the power supplied to the DC motor 52 in the rack to which the rightward signal or the leftward signal is transmitted from the other racks is set to such a level that the rack alone cannot start is pushed by one movable rack. This is to prevent the gap between the moving shelves from being created by the other moving shelves leading, and it is intended that one moving shelf pushes the other moving shelf. is there.

In each movable rack 52, it is judged whether or not the movable rack 52 has been pushed and moved in another movable rack (S15). In the pushed shelf, the power supply to the motor 52 is cut off (S17). In the pushed shelf, the rotational force of the traveling wheels is transmitted to the motor 52 and the motor 52 rotates to generate electricity (S18). In this way, the rack driven by being supplied with power by the motor 52 (the rack for pushing other racks) and the rack pushed by this rack travel for a predetermined distance to complete the formation of a passage of a predetermined width. (S16),
The operator stops the operation of the operation switch by himself and turns off the operation switch (S19).

When the operation switch is turned off, the power supply to the motor of the rack is stopped, and the direct-current motor of each movable rack is braked. In the mobile rack that has been used as a drive source to push other mobile racks, the terminals of the DC motor are connected through appropriate resistors, and the generated electric current is controlled to apply the power generation brake (S20). Similarly, in a shelf below the Digichain, that is, a shelf that is driven by another shelf, the terminals of the DC motor are connected through an appropriate resistor to control the generated electric current and apply the power generation brake ( S21). Power generation braking by current control is also applied to shelves other than these shelves, that is, shelves above the Digichain (shelf that did not move) (S22).
However, since no power is actually generated, no braking force is generated. The control for stopping the traveling of the shelves by applying the power generation brake based on the turning off of the operation switch is called normal brake control.

Since the above-described power generation braking force fluctuates as the load of the storage items loaded on the movable rack fluctuates, the stopping distance can be kept substantially constant even if the load fluctuates. it can. That is, when the load is large, the inertial force is also large, but the generated power is large and the power generation braking force is also large. On the other hand, when the load is small and the inertial force is small, the generated power and the generated braking force are also small.

Although the movable rack is quickly stopped by applying the power-generating brake, the terminal of the motor is short-circuited for about 0.1 to 1.0 seconds after the stop, and the state in which the power-generating brake is applied is maintained. (S23). Further, the drive current is not supplied to the motor while the generator brake is held. After the movable rack is stopped in this way, the power generation brake is released (S24). The power generation brake release may be performed immediately after the moving shelf is stopped or after 0.5 to 1.0 seconds has elapsed. This completes a series of operations.
Further, it is more preferable that other operations cannot be performed until about 1 second elapses after the operation of the operation switch is released.
When moving the movable rack again, the process returns to the beginning of the flow shown in FIG. 4 and the desired operation switch is selected.

Next, details of the emergency brake control will be described with reference to FIG. In FIG. 6, S31
5 to S34 are the same as S1 to S15 in FIG. 5, and S36 and S37 in FIG. 6 are S17 and S1 in FIG.
Same as 8. It is checked whether or not the safety device is activated while one shelf is pushing the other shelf (S35). The safety device mentioned here is a foreign matter detection sensor, that is, the left and right underframe safety bar switches 61 and 62 or the left and right passage safety bar switches 63 shown in FIG.
64. If the safety device does not operate, the movable shelves are further moved by pressing the operation switch to complete the formation of the passage of the predetermined width between the movable shelves (S4).
2) Release the operation of the operation switch to turn it off (S4
3) The normal brake control is performed (S44). The normal brake control has already been described.

When the safety device is activated in S35, the operating lamp 65 or 66 of the passage in which the safety device is activated is blinked to display that the safety device is activated (S38), and the power-generating brake is applied to each shelf. . In this case, it is necessary to stop the moving shelves urgently, so even if the shelves are pushing other shelves, the shelves being pushed by other shelves (lower shelves in the DigiChain) Without controlling the electricity generated by the motor with current, that is, in FIG.
The switch 20 shown in is closed and the terminals of the motor 52 are short-circuited to apply the dynamic braking (S39). Therefore, the motor is subjected to maximum dynamic braking and stops at a short stop distance. In addition, apply the power generation brake to other shelves, that is, the shelves above the Digichain (S
40).

After that, the process is the same as in the case of the above-described normal power-generating brake. That is, although the movable rack is quickly stopped by applying the power-generating brake, the motor terminal is short-circuited for about 0.1 to 1.0 seconds after the stop, and the state in which the power-generating brake is applied is maintained. (S4
1). Even after the moving rack has stopped, it is confirmed whether the safety device is working (S45), the safety device is turned off, and the power generation brake is maintained for about 0.5 seconds to 1.0 seconds (S4).
6) After that, the power generation brake is released (S47), and a series of operations is ended.

As described above, the power generation braking function is normally released while the movable rack is stopped. However, even when the moving racks are stopped, if the passage entry sensor outputs a detection signal or the foreign matter detection sensor outputs a detection signal, the DC motors of all the moving racks are made to function as a power generation brake. By doing so, even if an external force is applied to each of the movable shelves, the individual movable shelves do not unintentionally move, so that it is possible to prevent a person in the passage from being abruptly caught between the movable shelves.

As described above, when an earthquake happens to occur while the dynamic brake is functioning, the seismic energy is transmitted to the movable rack through the traveling wheels on which the braking force is applied, which causes the above-mentioned inconvenience. Therefore, it is configured to constantly detect whether or not the seismic sensing unit 57 detects an earthquake with a certain seismic intensity or more, and when the earthquake with a certain seismic intensity or more is sensed, the control circuit releases the power generation brake. To do. When the power generation brake is released, the mobile shelf will have a seismic isolation function, and the stored items will fall or fall,
It is possible to prevent problems such as the fall of the moving shelf.

FIG. 7 shows the operation and effect of the embodiment described above.
It will be described with reference to FIGS. By using the DC motor as the drive source of the moving rack, the moving rack can be moved quickly. FIG. 7A shows an example of a moving rack using a conventional AC motor. When starting the mobile shelf, "1
If a force of "0" is required, the AC motor has a small starting torque, so that the reduction ratio is increased to obtain the required torque at the time of starting and the required torque for each moving rack. Therefore, it takes 12 to 18 seconds to form a passage having a predetermined width (for example, 900 mm).

On the other hand, when a DC motor is used as a drive source like the electric movable rack according to the above-described embodiment, the starting torque is the maximum torque, so that a torque of "10" is generated when the movable rack is started. If necessary, the DC motor capable of obtaining the starting torque may be a motor having a smaller rated output than the AC motor. Alternatively, since there is a sufficient starting torque, it is possible to push and move a plurality of moving shelves with one moving shelf, as shown in FIG. 7B. Once it starts moving, the required torque is a fairly small torque, for example, a torque of "2" is enough. Also, due to the characteristics of the DC motor, the torque decreases as the rotation speed increases, so it is suitable for a moving rack. It can be said that it is a motor. Since the DC motor having such characteristics is used as the drive source, the reduction ratio of the drive system can be reduced, and the time required to form the required passage width is about 3 to 5 seconds. It can be greatly shortened compared to the moving shelves.

In the electric movable rack as in the illustrated embodiment, when the working passage is to be formed at a desired position, the moving racks on both sides of the position where the working passage is to be formed are moved to the right and left simultaneously. It can also be moved. For example,
As shown in FIG. 8 (a), when four moving shelves 2 are focused, when a work passage is to be formed in the center of the movable racks 2, the second rack from the right as shown in FIG. 8 (b) is used. The right-hand operation switch 4 of the movable rack 2 and the second movable rack 2 from the left
It is also possible to simultaneously operate the left-hand operation switch 6 to move the two right-side movable shelves to the right side and the left-side two movable shelves to the left side at the same time. By doing so, a working passage having a desired width can be quickly formed in a required time of about 3 seconds. Incidentally, FIG.8 (c) has shown the case where a movable shelf is moved only to one side. Even when it is moved to only one side, since the direct current motor is used as the drive source, the time required to form the work passage of the desired width is about 5 seconds, which is much shorter than the conventional moving rack. It is possible to remarkably speed up passage formation.

FIG. 9 shows how the dynamic brake operates. Stop the movement of the moving rack when the operation of the operation switch is stopped or the passage entry sensor is activated while the plurality of moving racks on the right side are being pushed by the second moving rack from the left. When it should be done, as described above, the terminals of the DC motor 52 of each movable rack are short-circuited, or the terminals are connected via a resistor to apply the power-generating brake. Since the drive motor is a DC motor, such a dynamic brake can be used. Further, since the power generation brakes can be applied to all the moving shelves, the moving shelves can be stopped smoothly and quickly.

FIG. 10 shows a state in which the passage entry sensor is activated and the movable shelf is stopped. When a person enters the passage between the movable shelves, the passage entrance sensor is activated as described above, the power generation brake is activated to stop all the movable shelves, and the DC motor continues to function as the power generation brake. In this state, interlock is applied, and all the operation switches are controlled so that they cannot be used, specifically, even if the operation switches are operated, they are ignored. A light source is built in the operation switches 4 and 6 of each movable shelf, and the light source of the operation switches 4 and 6 on the side of the movable shelf facing the passage where a person has entered blinks, Notify that the interlock is activated. In order to move the movable rack again, the reset switch is operated to release the interlock, and then the operation switch is selectively operated. The light source in the operation switches 4 and 6 is the operation lamp 6 shown in FIG.
It may be combined with 5, 66.

FIG. 11 shows a state in which the underframe safety bar switch, which is a foreign matter detection sensor, operates. This example
In the case where the underframe safety bar of a certain moving rack hits the foreign matter 20 and the underframe safety bar right switch 62 is operated, in this case also, all the moving racks stop moving, interlocked, and the foreign matter 20 exists. The light sources of the operation switches 4 and 6 on the side facing the passage blink to notify that the interlock is engaged. In order to move the movable rack again, after removing the foreign matter 20, the reset switch is operated to release the interlock, and the operation switch is selectively operated.

FIG. 12 shows a situation where an earthquake occurs while working in the passage between the movable shelves. Even if the generator brake happens to be applied when an earthquake occurs, as described above, the control circuit releases the generator brake function of the DC motor of each mobile rack and also shuts off the power supply to generate power to the DC motor. Since the braking function is released, the traveling wheels 8 rotate against the shaking of the floor surface and exert a seismic isolation effect.

In the illustrated embodiment, while the rightward operation switch 4 or the leftward operation switch 6 is being operated,
The mobile shelf moved to the right or left, it seems that people are pushing it by human power, and it is actually driven by electric power, it was a drive type that should be called a power assist type mobile shelf, but this book The technical idea of the invention can be applied not only to the power assist type movable rack but also to other drive type electric movable racks as long as a DC motor is used as a drive source. Further, in the illustrated embodiment, the drive motor of the movable rack pushed by one movable rack is designed to be supplied with power at the time of starting, but the drive motor of the movable rack to be pushed is not supplied with power at all. It may be driven only by one movable rack.

[0054]

According to the invention of claim 1 or 2,
Since the DC motor was used as the drive source, the DC motor functions as a dynamic brake when stopping the moving rack.
The moving rack can be stopped quickly. In addition, in an electric mobile rack that uses a DC motor as a drive source, the generator brake is configured to be released after the mobile rack stops, so even if an earthquake occurs while the mobile rack is stopped, it will run against the shaking of the floor. Wheels can rotate and seismic isolation effect can be obtained.

According to the third or fourth aspect of the present invention, when the passage entry sensor outputs a detection signal while the movable rack is moving or stopped, the DC motor is caused to function as a dynamic brake, and the detection signal Since it is configured to function as a power generation brake until the output stops, the movable rack cannot be moved while the passage entry sensor is operating, and the safety of the person in the passage can be improved.
Further, if the passage entry sensor is activated during movement, the movable rack is immediately stopped by the power generation brake, and the safety of the person in the passage can be secured.

According to the fifth aspect of the present invention, when the foreign matter detection sensor outputs a detection signal during movement of the movable rack, the DC motor is caused to function as a power generation brake, and power is generated until the output of the detection signal is stopped. Since it is configured to function as a brake, when the presence of a foreign object is detected, the power generation brake operates to immediately stop the moving rack. Further, the movable rack cannot be moved until the foreign matter is removed and the detection signal is stopped.

According to the invention described in claim 6 or 7, in the invention described in any one of claims 1 to 5, when the seismic sensing means senses an earthquake having a certain seismic intensity or more, the control circuit operates the DC motor. Since the function as the power generation brake is released, the same effect as that of the invention according to any one of claims 1 to 5 can be obtained, and when the earthquake occurs, the moving rack is provided with the seismic isolation function. Can be held.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of a control system applicable to an electric mobile shelf according to the present invention.

FIG. 2 is a front view showing an external appearance example of the electric mobile shelf according to the present invention.

FIG. 3 is a circuit diagram showing an example of a power-generating brake applicable to the present invention.

FIG. 4 is a flowchart showing an example of control operation by the control system.

FIG. 5 is a flowchart showing details of normal brake control by the control system.

FIG. 6 is a flowchart showing details of emergency brake control by the control system.

FIG. 7 shows a comparison of the effects of a conventional electric mobile shelf and an electric mobile shelf according to the present invention, in which (a) is a conventional example,
(B) is a front view showing an example of the present invention.

8A and 8B show an operation example of the electric mobile shelf according to the present invention, where FIG. 8A shows a state before operation, FIG. 8B shows a case of moving to the left and right sides, and FIG. 8C shows moving to only one side. It is a front view which shows each case.

FIG. 9 is a front view showing a state in which the power-generating brake is made to function in the electric mobile shelf according to the present invention.

FIG. 10 is a front view showing a state where the passage entry sensor operates in the electric movable shelf according to the present invention.

FIG. 11 is a front view showing a state in which a foreign matter detection sensor operates in the electric mobile shelf according to the present invention.

FIG. 12 is a front view showing a state where the vibration-sensing means operates in the electric mobile shelf according to the present invention.

FIG. 13 is a perspective view showing an external appearance example of an electric mobile shelf according to the present invention.

[Explanation of symbols]

2 mobile shelves 4 Right operation switch 6 Leftward operation switch 8 running wheels 52 DC motor 54 control circuit 57 Earthquake-sensing means 58 Passage entry sensor

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuya Tokunaga             3-8-1, Kamiakumamoto, Kumamoto-shi, Kumamoto Kongo             Within the corporation (72) Inventor Ichiro Ikenaga             3-8-1, Kamiakumamoto, Kumamoto-shi, Kumamoto Kongo             Within the corporation (72) Inventor Toshihiro Azuma             3-8-1, Kamiakumamoto, Kumamoto-shi, Kumamoto Kongo             Within the corporation F term (reference) 3F022 FF24 MM51 MM52 MM66 MM67                       NN21 NN51 PP06 QQ11

Claims (7)

[Claims] 1. An electric drive system comprising: a traveling wheel; a DC motor for rotating the traveling wheel forward and backward to reciprocate a movable rack; and a control circuit for driving the DC motor forward and backward by operating an operation switch. A mobile shelf, wherein the control circuit causes the DC motor to function as a power-generating brake when the mobile shelf stops. 2. The power generation brake is released after a certain period of time elapses after the movable rack is stopped.
The electric mobile shelf described. 3. An electric system comprising a traveling wheel, a DC motor for reciprocating the traveling wheel by reciprocating the traveling wheel forward and backward, and a control circuit for driving the DC motor forward and backward by operating an operation switch. A mobile rack, wherein a plurality of electric mobile racks are arranged so that they can be converged and separated, and a passage entrance sensor that detects when a person enters an aisle formed between the mobile racks is provided, and the control circuit comprises: When the passage entry sensor outputs a detection signal, the DC motors of all the moving shelves function as a dynamic brake, and the DC motors of all the moving shelves function as a dynamic brake until the passage entry sensor stops outputting the detection signal. An electric mobile shelf that is characterized by: 4. An electric system comprising a traveling wheel, a DC motor for reciprocally moving the traveling wheel to reciprocate a movable rack, and a control circuit for driving the DC motor to rotate forward and backward by operating an operation switch. A plurality of electric mobile shelves are arranged so that they can be converged and separated, and each of the electric mobile shelves is equipped with a passage entry sensor that detects when a person enters an aisle formed between the mobile shelves. The control circuit causes the DC motors of all the moving shelves to function as power-generating brakes when the passage entry sensor outputs a detection signal during the movement of the moving shelves to cause an emergency stop of the moving electric moving shelves, An electric mobile rack characterized in that the DC motors of all mobile racks function as power-generating brakes until the approach sensor stops outputting detection signals. 5. An electric system comprising a traveling wheel, a DC motor for rotating the traveling wheel forward and backward to reciprocate the movable rack, and a control circuit for driving the DC motor forward and backward by operating an operation switch. The movable shelves are arranged such that a plurality of electrically driven movable shelves can be converged and separated, and a foreign matter detection sensor that detects when a foreign matter comes in contact with a person or other foreign matter is arranged on the article loading / unloading surface of each movable shelf. Is, when the foreign matter detection sensor outputs a detection signal during the movement of the moving rack, causes the DC motors of all the moving racks to function as power-generating brakes to cause an emergency stop of the moving rack that is moving, and at the same time, the foreign matter detection sensor detects An electric mobile shelf characterized in that the DC motors of all mobile shelves function as generator brakes until the output of signals is stopped. 6. The electric movable rack according to claim 1, further comprising seismic sensing means, and when the seismic sensing means senses an earthquake with a certain seismic intensity or more, the control circuit causes a DC motor. An electric mobile shelf characterized by releasing the function as a power generation brake. 7. The electric movable rack according to claim 1, further comprising seismic sensing means, and when the seismic sensing means senses an earthquake with a certain seismic intensity or more, the control circuit turns on the power supply. An electric mobile shelf characterized by releasing the function of the DC motor as a power generation brake by cutting off.