JP2005350223A5 - - Google Patents

Description

Co-suspending hoist

  The present invention belongs to a technology that realizes two hoisting machines that hold a suspended load at two or more points and perform stable hoisting and lowering by simultaneous operation of two independent rope hoists, and in particular, misalignment of two hook positions. The present invention relates to a technique for minimizing control.

  Conventionally, a co-lifting hoist using two inverter-driven hoists only performs control for adjusting the hook position based on encoder pulses linked to the movement of the own hook detected by each hoist.

JP 2000-53382 A

  In the prior art, since the hook alignment is performed based on the hook interlocking pulse of the own machine, which is independently detected by the two hoists, the difference in the diameter of the rope winding drum, the difference in the initial elongation of the rope, etc. Regarding the individual difference between the two units, there is a problem that adjustment is not made between the hoists, and even if the same pulse count is controlled in the alignment control, the two hooks are displaced.

  The above problem is that an independent hook and an encoder that generates a pulse in conjunction with the upper and lower sides of the hook are provided, and the hook is inverter driven by recognizing the position of the hook by the pulse generated by the encoder. In a co-suspending hoisting machine that has two hoisting machines, and winds and lowers the rope by interlocking these two hoisting machines, the hooks of the two hoisting machines are operated at the same distance. This can be solved by correcting the number of pulses detected by the encoder based on the number of pulses generated by the encoder and operating the two hoisting machines in conjunction with each other.

  With this configuration, even when there are individual differences between the two hoists, the accuracy of hook alignment control is improved and the inclination of the suspended load is minimized, so that not only the suspended load delivery work can be accelerated, Safety is also greatly improved.

  In the above configuration, the correction is set by positioning two hooks at the same position near the upper limit of the range in which the hook operates, and then positioning the hook at the same position near the lower limit of the range in which the hook operates. May be.

  In addition, the problem is that an independent hook and an encoder that generates a pulse in conjunction with the upper and lower sides of the hook are provided, and the position of the hook is recognized by the pulse generated by the encoder, and the hook is connected to an inverter. In a co-suspending hoisting machine that has two hoisting machines to drive, and hoisting and lowering the rope by interlocking these two hoisting machines, the hooks of the two hoisting machines are the same distance Means for detecting the number of pulses when operated at a time, means for correcting the difference between these pulse numbers, and means for operating the two hoisting machines in conjunction with each other using the corrected pulse count number; This can be solved by having

  With this configuration, even if there are individual differences between the two hoists, the pulse count number is corrected so that the hook position and the pulse count number are synchronized, so the accuracy of hook alignment control is improved and the slant of the suspended load is minimized. Therefore, not only can the work of delivering suspended loads be speeded up, but the safety is also greatly improved.

  In the above configuration, the correction is set by positioning two hooks at the same position near the upper limit of the range in which the hook operates, and then positioning the hook at the same position near the lower limit of the range in which the hook operates. May be.

  In addition, the problem is that an independent hook and an encoder that generates a pulse in conjunction with the upper and lower sides of the hook are provided, and the position of the hook is recognized by the pulse generated by the encoder and the hook is driven by an inverter. A co-suspending hoisting machine that winds and lowers the rope by interlocking these two hoisting machines, and has a control unit that controls the alignment of the two hoisting machines, A means for adjusting the two pulse counts to the same value after adjusting the two hooks to the same position in the vicinity of the upper limit of the hook operating range, and the hook in the same position in the vicinity of the lower limit of the hook operating range. After the adjustment, the means for setting the two pulse count numbers at that time, and the correction coefficient for correcting the pulse count number by calculating the difference between the two set pulse count numbers Means for calculating, and correcting the number of pulses counted in conjunction with the hook position using a correction factor, it is solved by having a means to match the pulse count of two as with the actual hook position.

  With the above configuration, it is possible to minimize the displacement of the hook positions of the two hoists.

  With the above configuration, since the inclination of the suspended load is suppressed to the minimum within the range in which the hook can operate, not only the suspended load delivery operation can be speeded up, but also the safety is greatly improved.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a functional block diagram of a hoist according to the present embodiment. Reference numerals A and B respectively denote inverter drive hoists (hereinafter referred to as hoist A and hoist B), and the two hoists are linked by a single operation command device to perform a co-hung operation. Both hoists are each equipped with an overload detection function to ensure safety in co-suspended operation. Each has an abnormality detection function that stops operation when an abnormal condition occurs. And when one side stops in an overload state or an abnormal state, protection coordination is taken so that two hoists stop simultaneously.

  Hoists A and B include hoist control units 1a and 1b that control operation by a microcomputer, inverters 2a and 2b that drive induction motors 3a and 3b, brake brakes 4a and 4b that hold a load when stopped, induction motors 3a, It comprises encoders 5a and 5b that generate pulse signals in response to the rotation of 3b. An operation command device 6 is connected to the hook position control unit 7 to input an operation command to the hoists A and B. Moreover, it connects with the hoists A and B with the communication cable which transmits / receives a position signal and a control signal. In this embodiment, the operation command device 6 is described as a pendant push button, but the same applies to a case where a wireless operation transmitter, a programmable controller, a timer relay sequence, or the like is used. The above-described transfer of position signals and control signals between the two hoists is the same even if they are wireless.

  The hook position control unit 7 is controlled by a microcomputer 17 that operates according to a program, and includes an operation signal input unit 14, operation information input units 15a and 15b, and operation control signal output units 16a and 16b. The hoist control units 1a and 1b are controlled by microcomputers 10a and 10b that operate according to a program. The operation signal input units 11a and 11b, the brake control output units 18a and 18b, the inverter control output units 19a and 19b, the encoder signal input unit 20a, 20b, operation information output units 13a and 13b, and operation control signal input units 12a and 12b. The configuration of the hoist control unit is common to hoists A and B.

  FIG. 2 is an external view of the present embodiment. In each of the hoists A and B, the control panels 8a and 8b incorporate hoist control units 1a and 1b and inverters 2a and 2b. In this embodiment, the hook position control unit 7 is built in the hoist A. Reference numerals 9a and 9b denote hook blocks for suspending a load.

  Next, the flow from the operation signal input to the alignment operation will be described in order.

  When an operation input for winding or lowering is applied from the operation command device 6 to the operation signal input unit 14 of the hook position control unit 7, it is simultaneously applied to the hoist A and the hoist B. The respective operation signals are analyzed by the microcomputers 10a and 10b of the hoist control units via the operation signal input units 11a and 11b, and given as operation commands to the inverters 2a and 2b from the inverter control output units 19a and 19b. Thereby, in the hoist A and the hoist B, voltage is applied to the induction motors 3a and 3b at the same time, and the brake release timing is adjusted, and then the brake control output units 18a and 18b release the brake brakes 4a and 4b, respectively. The induction motors 3a and 3b start rotating, and the winding or lowering operation corresponding to the operation input is started at the same time.

  When the induction motors 3a and 3b rotate in the encoder units 5a and 5b of each hoist, pulse signals are generated in conjunction with the rotation of the induction motors 3a and 3b. In the microcomputers 10a and 10b, the input pulse signals are counted and held as position information of the hook blocks 9a and 9b. The hoists A and B transmit the position information from the operation information output units 13a and 13b to the hook position control unit 7 at regular intervals.

  The hook position control unit 7 compares and analyzes the received position information of the hoists A and B, and generates an operation control signal according to the estimated positional relationship and operation direction of the hook blocks. Thereafter, an operation control signal is sent to hoist A or hoist B, or both, to control the operation of the hoist so that the positional deviation between the hook blocks 9a and 9b is minimized.

  Next, a flow of alignment control performed in the hook position control unit will be described. FIG. 3 is a flowchart showing a series of flows.

  First, in the process 3-1, the positional relationship between the hook blocks of the two hoisting machines is checked from the pulse count numbers sent from the hoists A and B. When the hoist A is located above, the process branches to (1), and the operation direction is checked in process 3-2.

  In the case of hoisting operation, the operation branches to (2), and the operation frequency of the hoist A is decreased in processing 3-5. Since the preceding hoist A decelerates, the distance between the hooks is reduced. In the process 3-2, the process branches to (3) in the case of the winding operation, and the operation frequency of the hoist A is increased in the process 3-4. The distance between hooks is shortened because the hoist A to be chased accelerates.

  When the hoist B is positioned above in the process 3-1, the process branches to (4), and the operation direction is checked in the process 3-3. In the case of hoisting operation, the process branches to (5), and in processing 3-4, the operating frequency of the hoist A is increased and the distance between the hooks is shortened.

  In the process 3-3, the process branches to (6) in the case of the lowering operation, and in the process 3-5, the operation frequency of the hoist A is decreased to shorten the distance between the hooks. If hoists A and B are in the same position in process 3-1, the process branches to (7), and the operation frequency is maintained in process 3-6. This series of processes is repeated repeatedly during operation.

  In this way, the hook block positional relationship between the two hoisting machines is compared, the operating frequency of the hoist A is adjusted, the hoist A is caused to follow the hoist B, the position of the hook block is aligned, and the lowering operation is performed. . Although the flow when the hook position is set to the same position has been described here, the same applies when the positional relationship of the hook block is arbitrarily set and maintained, and can be used properly depending on the application and the state of the suspended load. It is. The same applies to the case where the operating frequency of the hoist B is adjusted so that the hoist B follows the hoist A. Further, when controlling not only one hoist but also the operating frequencies of two hoists at the same time, the idea is the same as long as the control is reversed.

  As described above, the two rope hoists are aligned based on the number of pulses generated by the encoder, and therefore it is important that the hook block position is synchronized with the number of pulses. However, since two rope hoists are used, individual differences such as differences in the winding diameter of the rope winding drum and elongation of the wire rope occur in each hoist. There are methods to improve manufacturing accuracy and use materials with the same characteristics when selecting materials, but this is not practical in terms of cost. Therefore, there is a limit to improving the alignment performance simply by comparing the number of encoder pulses. Therefore, as shown below, by setting a reference point for position detection at the time of installation or periodically, the individual difference between the two units is input to correct the pulse count number to minimize the shift of the hook block.

  In the present embodiment, an example will be described in which an upper reference point and a lower reference point are set, and the pulse count number is corrected by a correction coefficient output therefrom.

  In FIG. 4, A is a hook block of the hoist A, and B is a hook block of the hoist B. As indicated by reference numeral 4-1, the positions of both hook blocks are adjusted to the same position in the vicinity of the winding upper limit, and the values of the mutual pulse counters are cleared to zero as the upper reference point of the position detection process. At this time, it is important to suspend a certain amount of load on the hook block so that the rope is not loosened. Next, it is operated and stopped simultaneously until the lowering lower limit. At this time, it starts simultaneously and stops at the same time, but as described above, the pulse counters coincide as shown by reference numeral 4-2 due to the influence of individual differences, but there is a difference between the positions of the two load blocks. Arise.

  Next, as indicated by reference numeral 4-3, one is moved by an independent operation to adjust the hook block to the same position. By doing so, the difference in hook position due to individual differences is detected by the number of pulses. When the number of pulses at the position stopped by simultaneous operation is set to 1000, the counter value becomes 1010 by moving the hook block of B to the same position, and there is a difference of 10 pulses (1010−1000 = 10). become. Then, this state is set as the lower reference point, and the correction coefficient of the pulse counter is determined. The correction coefficient is a coefficient that makes the pulse counter have the same numerical value in accordance with the position of the hook block, and is a ratio of the pulse counter value.

  In the case of the example indicated by reference numeral 6-3, since the pulse count number of the hook block A is 1000 and the same value of the hook block B is 1010, the correction coefficient is calculated as 0.99 from the expression 1000/1010 = 0.99. The When the lower reference point is set, the correction coefficient is automatically calculated from the two pulse counts and held in the hook position control unit. The pulse count number of the hook block B is corrected by this correction coefficient, and the pulse count number is synchronized with the positional relationship of the hook.

  In the state indicated by reference numeral 4-3, the pulse count number of the hook block B is corrected to 1000 (1010 × 0.99 = 1000), and the pulse count number can be made the same as the position of the hook block A. This correction is effective over the entire operating range of the hook block. For example, considering the case where the pulse count number of the hook block A is 500 and the hook block B is also in the same position, the pulse count number of the hook block B is proportionally 505. Since the correction is effective over the entire operation range, the numerical value used for detecting the position of the hook block is 500 because it is corrected to 505 × 0.99 = 500, and the pulse count number matches the same as the hook position.

Functional block diagram. External view. The alignment control flowchart. Hook block state diagram.

Explanation of symbols

  A ... A hoist, B ... B hoist, 1a ... A hoist control unit, 1b ... B hoist control unit, 2a ... A hoist inverter, 2b ... B hoist inverter, 3a ... A hoist induction motor, 3b ... B hoist induction motor, 4a ... A hoist braking brake, 4b ... B hoist braking brake, 5a ... A hoist encoder, 5b ... B hoist encoder, 6 ... operation command device, 7 ... hook position controller, 8a ... A hoist control panel, 8b ... B hoist Control panel, 9a ... A hoist hook block, 9b ... B hoist hook block, 10a ... A hoist control unit microcomputer, 10b ... B hoist control unit microcomputer, 11a ... A hoist operation signal input unit, 11b ... B hoist operation signal Input unit, 12a ... A hoist operation control signal input unit, 12b ... B IST operation control signal input unit, 13a ... A hoist operation information output unit, 13b ... B hoist operation information output unit, 14 ... operation signal input unit, 15a ... A hoist operation information input unit, 15b ... B hoist operation information input unit, 16a ... A hoist operation control signal output unit, 16b ... B hoist operation control signal output unit, 17 ... hook position control unit microcomputer, 18a ... A hoist brake control output unit, 18b ... B hoist brake control output unit, 19a ... A Hoist inverter control output unit, 19b ... B hoist inverter control output unit, 20a ... A hoist encoder signal input unit, 20b ... B hoist encoder signal input unit.

Claims (4)

An independent hook and an encoder that generates a pulse in conjunction with the upper and lower sides of the hook are provided, and two windings for recognizing the position of the hook by the pulse generated by the encoder and driving the hook with an inverter. In a co-suspending hoisting machine that has an upper machine and performs the hoisting and lowering of the rope by interlocking these two hoisting machines, when the hooks of the two hoisting machines are operated at the same distance, A co-lifting hoist that operates by linking the two hoisting machines by correcting the number of pulses detected by the encoder based on the number of pulses generated by the encoder. 2. The co-suspending hoist according to claim 1, wherein the correction is performed by positioning two hooks at the same position in the vicinity of the upper limit of the range in which the hook operates, and then in the vicinity of the lower limit of the range in which the hook operates. A hoisting hoisting machine that is set by positioning at the same position. An independent hook and an encoder that generates a pulse in conjunction with the upper and lower sides of the hook are provided, and two windings for recognizing the position of the hook by the pulse generated by the encoder and driving the hook with an inverter. In a co-suspending hoisting machine that has an upper machine and performs the hoisting and lowering of the rope by interlocking these two hoisting machines, a pulse is generated when the hooks of the two hoisting machines are operated at the same distance. A co-wound hoisting means comprising means for detecting the number, means for correcting the difference between these pulse numbers, and operating means for operating the two hoisting machines in conjunction with each other using the corrected pulse count number Machine. The co-lifting hoist according to claim 3, wherein the correction is performed by positioning two hooks at the same position in the vicinity of the upper limit of the range in which the hook operates, and then in the vicinity of the lower limit of the range in which the hook operates. A hoisting hoisting machine that is set by positioning at the same position.