JP3329712B2 - Stop position correction device for lifting equipment in lifting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for correcting an error between a set lifting end stop position and an actual lifting end stop position of a hoist due to extension of a suspension cable of a lifting device.

[0002]

2. Description of the Related Art In a device for raising and lowering a moving body such as a hanging tool or a gripper suspended by a hanging rope such as a chain or a rope by lifting or lowering the hanging rope, the lifting or winding of the hanging rope is performed. An encoder, a position detector such as a resolver phase shifter, etc. are provided in the lowering drive device to detect position data,
Techniques for accurately stopping a moving body at a desired vertical position based on the data are well known. Further, some of these types of elevating devices are configured to correct an error when an error occurs between the set position data and the actual stop position due to extension of the suspension cable.

For example, Japanese Patent Publication No. Sho 61-53316 discloses that a moving body suspended on a suspension cable is moved along a guide rail, and the absolute position of the moving body at this time is detected by an absolute position detector. In a hoisting machine, a dog provided on a moving body, a dog detector provided at a desired fixed position along a guide rail to detect passage of the dog, and a reference absolute position corresponding to the fixed position of the dog detector A setter for setting data, a correction amount calculating circuit for comparing the detected absolute position data of the absolute position detector with the reference absolute position data of the setter when the dog detector detects the passage of the dog, and obtaining a correction amount. An adder for adding the correction amount of the correction amount calculation circuit and the detected absolute position data of the absolute position detector to output corrected absolute position data, and the position data of the position detector according to the extension of the suspension cable. Correct Hoisting the moving body is always the same level position stop and to stop at the position correction apparatus is disclosed a.

[0004] However, the above-mentioned stop position correcting device is suitable for moving a moving body suspended on a suspension cable along a guide rail, but is suitable for moving the moving body up and down without a guide rail. There is a problem that the moving body is rolled and the distance between the dog and the dog detector is not kept constant, so that reliable detection cannot be performed.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and ensures reliable detection even when a moving body suspended on a suspension cable is lifted and lowered without a guide rail. It is an object of the present invention to provide a hanger stop position correcting device that can be used.

[0006]

According to the present invention, in order to solve the above-mentioned problem, a distance sensor is installed upward on a floor directly below a moving body, and a distance between a reference lower end position of the moving body and the distance sensor is set. (C) is compared with the actual lower end position of the moving body and the distance (D) between the distance sensor to obtain a correction value (CD), and the set position data of the position detector is calculated based on the correction value. The gist is to make corrections.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of an elevating device provided with a hanger stop position correcting device according to the present invention. In the figure,
Reference numeral 1 denotes an electric motor installed horizontally on a gantry 2, and a drive gear 4 is attached to an output shaft 3 of the electric motor 1. A driven gear 5 is provided on the gantry 2 in parallel with the drive gear 4, and a drive chain 6 is looped between the gears 4 and 5. The driven gear 5 is hung around a hoisting chain 9 having a hoist 7 attached at one end and a weight 8 at the other end, and the hoist 7 is raised and lowered by forward and reverse rotation of the electric motor 1. An encoder (not shown) for detecting the rotation amount of the shaft 3 is attached to the output shaft 3 of the electric motor 1, and the encoder is connected to a controller 12 via a conductor 11. Reference numeral 13 denotes a conductor for transmitting a drive start / stop command signal from the controller 12 to the electric motor 1.

A distance sensor 14 for measuring a distance from the hanging member 7 is installed upward on the floor directly below the hanging member 7, and the distance sensor 14 is connected to the controller 12 via a conducting wire 15. Connected. FIG. 2 shows a block diagram of the position correcting device 16 of the hanging tool in the controller 12, and the setting device (A) 17 stores the hanging tool 7 as an initial value.
When the detected rotation amount of the encoder matches the data, the drive of the electric motor 1 is stopped by a command from the controller 12, and Lifting is stopped. Note that the reference rising end position data is expressed as a distance (L2) from the tangent position of the chain 9 to the reference rising end position (A) in the driven gear 5, and the reference falling end position data is the chain 9 in the driven gear 5. From the tangent position to the reference lower end position (B).

Reference numeral 18 denotes a counter which counts each time the encoder detects the lowering end position of the hanging member 7 based on the set reference lowering end position data (L1). Is counted, the distance sensor 14 is activated, and the distance data (D) between the actual lower end position of the hanging member 7 and the distance sensor 14 is output to the storage circuit 19 and stored therein. Note that the set count number is a facility operation cycle until the amount of extension of the lifting chain 9 reaches the allowable limit of the suspension position. On the other hand, the interval data (C) between the reference lower end position (B) of the hanging member 7 and the distance sensor 14 is supplied from the setting device (B) 21 to the comparison operation circuit 22 and the interval data stored in the storage circuit 19 is stored. A comparison operation is performed with (D), a difference value (C-D) is output, and the difference value is supplied to the subtractor 23. A setter (A) is connected to the other input terminal of the subtractor 23.
17, the reference falling end position data (L1) of the hanging member 7 is supplied, and the subtractor 23 subtracts the former input data (C-D) from the latter input data (L1) to obtain corrected falling end position data ｛L1. − (CD)}.

The operation circuit 24 has one input terminal supplied with the difference value (CD) of the comparison operation circuit 22 and the other input terminal receives the driven gear 5 from the setter (B) 21. (L) from the axial center level position to the reference lower end position (B).
The ratio value (L2 / L1) of the distance (L2) from the axial center position of the driven gear 5 to the reference ascending end position (A) is supplied, and the multiplication of both input data ΔL2 / L1 · (C −
D)｝ is performed. The multiplied value of the arithmetic circuit 24 is added to the adder 25.
Supplied to The other input end of the adder 25 is provided with reference set end position data (L
2) is supplied, and the input data {L2, L2 / L1 · (CD)} of the two are added by the adder 25 and output as corrected rising end position data {L2 + L2 / L1 · (CD)}. You.

In the lifting device constructed as described above, the rising end position of the hanging member 7 is set to the reference rising end position (A), and the setting device (A) 17 sets the reference lifting position of the hanging member 7 as an initial value. With the end position data (L2) and the reference lower end position data (L1) input, the motor 1 is driven to start the lifting / lowering operation of the hanging member 7. When the lifting / lowering operation of the lifting device 7 reaches the set cycle, the lifting device 7 at that time is
(C-D) of the distance data (D) between the actual lower end position and the distance sensor 14 and the distance data (C) between the reference lower end position (B) of the hanging member 7 and the distance sensor 14. Is performed, and based on the calculation result, the corrected falling edge position data {L1- (CD)} is set from the subtractor 23 to the setting unit (A) 17
Is output to and replaced with the initial setting value. That is, since the rotation amount of the output shaft 3 of the electric motor 1 is reduced by an amount corresponding to the elongation of the chain, when the hoisting chain 9 is lowered in the next cycle, the hoist 7 stops at the reference lower end position (B).

At the same time, the difference value (C
-D), the distance (L1) from the axial center position of the driven gear 5 to the reference lower end position (B), and the distance (L2) from the axial center position of the driven gear 5 to the reference ascending end position (A). Multiplication with a ratio value (L2 / L1) of と L2 / L1 · (C−
D)} is performed, and the adder 25 outputs corrected rising edge position data {L2 + (L2 / L1 · (C−
D) is output to the setting device (A) 17 and is replaced with the initial setting value. That is, the rotation amount of the output shaft 3 of the electric motor 1 is increased by an amount corresponding to the elongation of the chain.
Is lifted, the hanging tool 7 stops at the reference rising end position (A).

[0013]

According to the present invention as described above, an error can be reliably detected even if the hanging tool rolls up and down.
A guide device such as a guide rail is not required, and equipment costs can be reduced.

[Brief description of the drawings]

FIG. 1 is a front view of an elevating device provided with a hanger stop position correcting device according to the present invention.

FIG. 2 is a block diagram of a hanger stop position correcting device according to the present invention.

[Explanation of symbols]

 Reference Signs List 7 hanging tool 9 hanging cable 14 distance sensor 18 counter 19 storage device 22 comparison operation circuit 23 subtractor 24 operation circuit 25 adder

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B66D 1/46 B66B 1/40

Claims (1)

(57) [Claims] 1. A lifting device for raising and lowering a hanging member 7 suspended on a hanging line 9 by hoisting or lowering the hanging line 9 and controlling a stop position of the hanging member 7 via a position detector. And a distance sensor 14 installed upward on the floor immediately below the hanging member 7 to measure an interval between the hanging member 7 and the position detector. A counter 18 that counts each time the falling end position of the hanging member 7 is detected; and when the counter 18 counts a predetermined number, interval data (D) between the actual falling end position of the hanging member 7 and the distance sensor 14. And a storage value of the storage circuit 19, and a difference value (C-D) obtained by comparing the storage content of the storage circuit 19 with the distance data (C) between the reference lower end position of the hanging member 7 and the distance sensor 14. ) For the comparison operation circuit 22
A subtractor 23 for subtracting and correcting the set position data of the position detector based on a difference value of the comparison operation circuit 22; a distance (L1) to a reference lower end position of the suspension cable 9 and a reference rise; The multiplication value (L) is calculated based on the ratio of the distance to the end position (L2) and the difference value (CD) of the comparison operation circuit 22.
2 / L1 · (C−D)), and an adder 25 for adding and correcting the set position data of the position detector based on the multiplied value of the arithmetic circuit 24. A lifting position correction device for a lifting device in a lifting device.