JPH07197689A - Speed monitor - Google Patents

Abstract

PURPOSE:To monitor the speed of a conveyor even at the time of stoppage on any rack stage. CONSTITUTION:A position sensor 11 detects the current position 17 of a conveyor carrying load, a displacement-quantity arithmetic section 29 obtains the quantity of displacement 27 at every fixed time of the conveyor on the basis of the position 17, and a reference displacement-quantity generating section 33 acquires the reference quantity of displacement 32 corresponding to a stopping distance 31 up to a position, where the conveyor must be stopped, from the current position 17 of the conveyor. An arithmetic control section 34 takes the deviation of the quantity of displacement 27 and the reference quantity of displacement 32, and transmits a control signal 18 over a driving gear 10 for the conveyor in response to the deviation, thus monitoring the speed of the conveyor at all times.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed monitoring device used in a transportation device such as an elevator parking device.

[0002]

2. Description of the Related Art FIG. 6 shows an example of an elevator parking apparatus. A building 1 constructed on the ground has a loading / unloading section 3 for a load such as a vehicle 2 and a transportation path 4 extending vertically from the loading / unloading section 3.
Is provided, and a pallet 5 for mounting the vehicle 2 is provided on the transport path 4.
A carrier 6 such as a cage for moving up and down is provided so as to be able to move up and down.
A plurality of shelves 7 for storing the data are provided.

At the top of the building 1, a sprocket 8 for raising and lowering the carrier 6 via a chain (not shown) is used.
Is provided, and the sprocket 8 is connected to a drive device 10 via a speed reducer 9.

Reference numeral 11 is a position detector such as an encoder provided coaxially with the sprocket 8, reference numerals 12 and 13 are a pair of limit switches for detecting a rise provided above the building 1, and reference numerals 14 and 15 are the building 1. 2 is a pair of limit switches for detecting a descent that is provided below the.

When the vehicle 2 is stored, first of all,
The vehicle 2 is self-propelled and loaded into the building 1 from the loading / unloading section 3, and further, the vehicle 2 is loaded on the pallet 5 on the carrier 6 such as a cage waiting in the loading / unloading section 3.

Next, the drive device 10 is driven, the sprocket 8 is rotated through the speed reducer 9, and the chain (not shown) suspended on the sprocket 8 is moved to raise the carrier 6 connected to the chain. Let

Finally, the carrier 6 is stopped at the side of the empty shelf 7, and the transfer device (not shown) attached to the carrier 6 stores the vehicle 2 together with the pallet 5 in the shelf 7.

When the vehicle 2 is to be unloaded, the procedure substantially opposite to the above is carried out.

The elevator type parking system has the advantage that the carrier 6 can be moved at a high speed and the vehicle 2 can be loaded and unloaded in a short time. Therefore, the speed of the carrier 6 becomes too high and an accident occurs. In order to prevent such a situation, it is necessary to provide a means for regulating the speed of the carrier 6.

Therefore, conventionally, when the carrier 6 rises, the carrier 6 accelerates (acceleration region) as shown in FIG. 7, reaches the maximum speed, and moves for a predetermined distance (constant velocity region). Since deceleration is started (deceleration area), a pair of limit switches 12 for detecting ascent are located at a position within the deceleration area at a distance allowing a sudden stop to the uppermost part of the building 1.
When 13 is provided and the carrier 6 descends, as shown in FIG. 8, the carrier 6 accelerates (acceleration range), reaches the maximum speed and moves for a predetermined distance (constant speed range), and then starts deceleration. Therefore, the pair of limit switches 14 and 15 for lowering detection are located at a position within the deceleration area at a distance allowing a sudden stop up to the loading / unloading section 3 at the bottom of the building 1.
Limit switches 12, 13 or 14, 1
5, the carrying time of the carrier 6 passing between the limit switches 12 and 13 or between 14 and 15 is detected, and when the passing time is shorter than a preset time, it is determined that the deceleration is insufficient or the speed is abnormal. Then, the carrier 6 was made to stop urgently.

[0011]

However, the conventional speed monitoring device described above has the following problems.

That is, the limit switches 12, 13 and 1
Since the pairs 4 and 15 were provided only in the upper part and the lower part of the building 1, respectively, they cannot be used except when the carrying device 6 monitors the loading / unloading part 3 and the uppermost part so as not to go too far. For example, it cannot be used as a speed monitoring device for safely and surely stopping the carrier 6 on each floor.

In view of the above situation, it is an object of the present invention to provide a speed monitoring device capable of monitoring the speed of a carrier regardless of which shelves are stopped.

[0014]

SUMMARY OF THE INVENTION According to the present invention, a position detector for detecting the current position of a carrier for carrying a load and a displacement amount of the carrier for a constant time based on the position detected by the position detector. A displacement amount calculation unit to be obtained, a reference displacement amount generation unit to obtain a reference displacement amount according to a stop distance from the current position of the carrier to a position to be stopped, and a drive according to a deviation between the displacement amount and the reference displacement amount. According to another aspect of the present invention, there is provided a speed monitoring device including an arithmetic control unit that sends a control signal to the device.

[0015]

The operation of the present invention is as follows.

The position detector detects the current position of the carrier carrying the load, and based on the position, the displacement amount calculator calculates the displacement of the carrier at regular time intervals.

Further, the reference displacement amount generating section obtains the reference displacement amount according to the stop distance from the current position of the carrier to the position where it should be stopped.

Then, the arithmetic control unit takes a deviation between the displacement amount and the reference displacement amount, and sends a control signal to the drive device of the carrier according to the deviation.

In this way, by taking the displacement amount of the carrier at regular time intervals and comparing it with the reference displacement amount,
The speed of the carrier can be monitored.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 5 show an embodiment of the present invention.

Since the basic structure of the elevator type parking system is almost the same as that of FIG. 6, FIG. 6 will be referred to when necessary.

Further, in FIG. 1, 10 is a drive device for an elevator type parking apparatus, 11 is a position detector of a carrier such as an encoder, 16 is a drive based on the current position 17 of the carrier detected by the position detector 11. A control device that sends a control signal 18 to the device 10, 19 is a speed monitoring device provided inside the control device 16, and 20 is an input unit for the control device 16.

As shown in FIG. 2, the speed monitor 19 keeps the current position 17 of the carrier detected by the position detector 11 constant according to a time pulse 22 generated by a clock 21 inside the controller 16. A counter 23 that is input at each time, and a switching unit that switches the signal of the position 17 sent from the counter 23 at regular intervals according to the time pulse 22 and alternately sends it to a pair of position data holding units 24 and 25. A displacement amount calculation unit 29 is provided, which includes a reference numeral 26 and a subtracter 28 which obtains a displacement amount 27 in a constant time by taking a deviation between the two positions 17 held in the position data holding units 24 and 25.

Further, the speed monitoring device 19 includes the position detector 11
A stop distance for obtaining the stop distance 31 of the transporter up to the position to be stopped by taking the deviation between the current position 17 of the transporter detected in 1 and the stop position 30 of the transporter input from the input unit 20 of the control device 16. The calculation unit 32 and the reference displacement amount generation unit 33 that obtains the reference displacement amount 32 according to the stop distance 31 based on the signal of the stop distance 31 from the stop distance calculation unit 32 are provided.

It should be noted that the reference displacement amount 32 is set in advance in the reference displacement amount generating section 33 to an upper limit value and a lower limit value.

Further, the speed monitoring device 19 uses the displacement amount 2
7 is compared with the reference displacement amount 32 to control the speed of the carry device or to send a control signal 18 to the drive device 10 for emergency stop of the carry device.

Next, the operation will be described.

The process in which the elevator type parking apparatus moves the carrier up and down to store the load such as the vehicle 2 in each shelf is the same as that shown in FIG.

In the elevator type parking system, the position detector 11 such as an encoder always detects the current position 17 of the carrier, sends the position 17 to the control unit 16, and the control unit 16
Drive the control signal 18 based on the signal at position 17
It is sent to 0 to control the lifting and lowering of the carrier.

Further, in the present invention, in addition to the above control, a signal of the current position 17 of the carrier detected by the position detector 11 is sent to the speed monitor 19 provided inside the controller 16.
To monitor the speed of the carrier as follows.

That is, first, in the displacement amount calculation unit 29 of the speed monitoring device 19, the clock 21 generates the time pulse 22, and the counter 23 causes the position detector 11 to detect the time pulse 22 at regular intervals according to the time pulse 22. Current carrier position 1
7 is input, the switching unit 26 performs the switching operation at the constant time intervals, the position 17 from the counter 23 is alternately sent to the position data holding units 24 and 25, and the subtractor 28 is moved to the position data holding units 24 and 25. The deviation amount 27 of the two is obtained by taking the deviation of the data of the position 17 from the.

Specifically, for example, when the carrier moves from the loading / unloading port to the uppermost part, the position 17 of the carrier changes as shown in FIG. 3 with the passage of time, and the position detector 11 always keeps this. Although it is detected, the counter 23, as shown in FIG. 4, has a constant time Δt corresponding to the time pulse 22.
In addition, the current position 17 of the carrier is input from the position detector 11, the switching unit 26 alternately sends the position 17 to the position data holding units 24 and 25, and the position data holding units 24 and 25 set the position 17 to the value D. ₁ and D ₂ , and the subtracter 28 uses the deviations (X ₁ , X ₂ , X _{2) of} the values D ₁ -D ₂ , D ₂ -D ₁ , D ₁ -D ₂ ...
₃ ) and take the deviation as the displacement amount 27.

The displacement amount 27 per unit time thus obtained is almost equal to the speed of the carrying device at that position, and becomes smaller as the carrying device approaches the stop position.

Simultaneously with the calculation of the displacement amount 27, the speed monitoring device 19 uses the stop distance calculation unit 32 to input the position 17 from the position detector 11 and the input unit 20 at the time of loading / unloading. The distance from the stop position 30 to the stop position 30, that is, the stop distance 31, is determined, and the reference displacement amount generation unit 33 determines the reference displacement amount 32 according to the stop distance 31.

The reference displacement amount 32 has a smaller value as the stop distance decreases, and is set in advance as an upper limit value a and a lower limit value b, for example, as shown in FIG.

Finally, the calculation control unit 34 calculates the displacement amount 27 calculated by the displacement amount calculation unit 29 and the reference displacement amount generation unit 33.
It is compared with the reference displacement amount 32 obtained in.

As a result of the comparison, the displacement 27 is the reference displacement 32.
If the range of the upper limit value a and the lower limit value b is exceeded, the arithmetic control unit 34 sends a control signal 18 to the drive device 10 to control the speed of the carry device to an optimum speed or to make an emergency stop of the carry device. To do.

As described above, by always detecting the displacement amount 27 of the carrier, it is possible to monitor and control the speed of the carrier regardless of which shelf the stop position is.

The present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

[0041]

As described above, according to the speed monitoring device of the present invention, it is possible to achieve an excellent effect that the speed of the carrier can be monitored regardless of which shelves are stopped.

[Brief description of drawings]

FIG. 1 is an overall schematic system diagram of an embodiment of the present invention.

FIG. 2 is an enlarged view of FIG.

FIG. 3 is a graph showing the relationship between time and the position of the carrier.

FIG. 4 is a graph showing a relationship between time and a moving distance of a carrier.

FIG. 5 is a graph showing a relationship between a stop distance and a reference displacement amount.

FIG. 6 is a schematic front view of an elevator parking device.

FIG. 7 is a graph showing the relationship between the position and speed of the carrier when the carrier is raised according to the conventional example.

FIG. 8 is a graph similar to FIG. 7, showing the relationship between the position and speed of the carrier when the carrier is lowered.

[Explanation of symbols]

 2 load (vehicle) 6 carrier 11 position detector 17 position 27 displacement amount 29 displacement amount calculation unit 31 stop distance 32 reference displacement amount 33 reference displacement amount generation unit 10 drive device 18 control signal 34 calculation control unit

Claims (1)

[Claims] 1. A position detector for detecting the current position of a carrier for transporting a load, a displacement amount calculation unit for obtaining a displacement amount of the carrier for a certain period of time based on the position detected by the position detector, and a carrier. A reference displacement amount generating section for obtaining a reference displacement amount according to the stop distance from the current position to the position to be stopped, and arithmetic control for sending a control signal to the drive device according to the deviation between the displacement amount and the reference displacement amount. And a speed monitoring device.