JPS6357333B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a synchronous operation control circuit for a conveyor in which two independently driven conveyors are arranged in series and workpieces are delivered and conveyed between the conveyors. .

Conventionally, in this type of conveyor, in order to ensure that workpieces are transferred between both conveyors, for example, when a workpiece on one conveyor reaches the workpiece transfer position, a hanger for hanging the workpiece on the other conveyor is moved. It is necessary to be able to position it at the workpiece delivery position. Therefore, after matching the synchronous positions of both conveyors, both conveyors are started to operate simultaneously, and the operation of both conveyors is controlled to be in a synchronous operation state based on a synchronous signal from a synchronous operation control circuit. (For example, see Japanese Patent Publication No. 52-35175).

However, during synchronized operation of both conveyors, if one conveyor stops due to a failure or as necessary, in order to keep the synchronized positions of both conveyors corresponding to each other, it is necessary to immediately stop the other conveyor. Alternatively, after operating the other conveyor to a predetermined point and stopping it, it is necessary to operate the one conveyor independently to a point corresponding to the predetermined point after restoration. Therefore, there is no degree of freedom in operation between the conveyors, and when one conveyor stops, the operating rate of the other conveyor decreases. Furthermore, when the other conveyor corresponds to a conveyor in a painting line, for example, there is a drawback that the quality of the workpieces deteriorates due to the temporary stop of the conveyor.

In view of this, the present invention detects the electrical phase difference between the synchronized positions between both conveyors to generate a phase discrimination signal, and based on this phase discrimination signal and the conventional synchronization signal, the workpiece By determining when to start synchronized operation to ensure delivery and conveyance, even if one conveyor stops when both conveyors are in synchronized operation, the other conveyor continues to operate without being forced to stop. The purpose of this invention is to automatically determine when to start synchronous operation and to start synchronous operation once one of the conveyors is restored and resumes operation.

In order to achieve the object, the present invention provides a synchronized operation control circuit for a conveyor in which two independently driven conveyors are arranged in series and workpieces are delivered and conveyed between the conveyors. A synchronization transmitter that electrically detects the conveyance position; a synchronization control unit that receives the conveyance position signal from the synchronization transmitter and outputs a synchronization signal and phase discrimination signal between both conveyors; and a synchronization signal of the synchronization control unit. a position control section that converts into a speed signal; a synchronization detection section that determines synchronization timing using the synchronization signal and phase discrimination signal of the synchronization control section and outputs the synchronization timing signal; and a synchronization detection section that receives the synchronization timing signal of the synchronization detection section. and a speed control unit that outputs the speed signal of the position control unit to the drive means of the other conveyor, and when both conveyors are operated simultaneously by restarting operation of one conveyor, when the synchronization timing comes, the synchronization detection unit A speed signal corresponding to the synchronization signal of the position control section is inputted to the driving means of the other conveyor by outputting the synchronization timing signal of the conveyor, thereby starting synchronized operation of both conveyors.

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

In FIG. 1, 1 is a first conveyor, and 2 is a second conveyor arranged in series with the first conveyor 1.
is a conveyor, each of which conveys a workpiece (not shown) to the left in the figure.
The driving pulley 1a of the first conveyor 1 includes a first
A first motor 4 is connected to the drive pulley 2a of the second conveyor 2 via an electromagnetic clutch 3, and a second motor 4' is connected to the drive pulley 2a of the second conveyor 2 via a second electromagnetic clutch 3'. While each of the conveyors 1 and 2 is driven independently by driving the conveyors 4 and 4', works (not shown) on the second conveyor 2 are delivered and conveyed to the first conveyor 1 at predetermined pitch intervals. It is designed to repeat. Also,
Each of the motors 4, 4' is operated based on the voltage signal of a speed detection generator 5, 5' which converts the rotation speed of each motor 4, 4' into a voltage signal. First and second speed control sections 6, 6' are connected to each other for feedback controlling the rotation speed to a preset set rotation speed, and each speed control section 6, 6' controls each motor 4, 4'. Each of the conveyors 1 and 2 is driven at a predetermined speed by controlling the rotation speed. In addition, 7 indicates each speed control section 6, 6'
This is a speed setting section for inputting the set rotation speed of the motor.

Reference numeral 8 denotes a synchronization transmission unit that electrically detects the transport position of a workpiece (not shown) on the first conveyor 1 based on the rotation of the driven pulley 1b of the first conveyor 1; The synchro control section 9 is an important part of the invention, and receives the conveyance position signal from the synchro transmitter 8 to determine whether the conveyance position of the workpiece is the workpiece (not shown) on the first conveyor 1. Calculate the time t required to move the distance corresponding to the transport pitch of The faster the workpiece movement speed is, the higher the frequency of the synchronization signal is. pulley 2a
The conveyance position of the workpiece (not shown) on the second conveyor 2 is electrically detected based on the rotation of the second conveyor 2, and the electrical phase difference between this conveyance position signal and the conveyance position signal from the synchro transmitter 8 is detected. This is taken out as an alternating current voltage and outputs a cosine curved phase discrimination signal as shown in FIG. 2(b). Also, 10
receives the synchronization signal (frequency signal) from the synchronization control section 9, converts this synchronization signal into a voltage signal (the higher the frequency, the higher the voltage) by a frequency-voltage conversion circuit, and converts this voltage signal into the first signal. conveyor 1
The speed signal of the position control unit 10 is obtained as a speed signal by a speed output unit 12, which will be described later.
It is output to the second speed control section 6' via.

Further, 11 is a synchronization detection section that receives a synchronization signal and a phase discrimination signal from the synchronization control section 9, and the synchronization detection section 11 is configured such that the synchronization signal has a substantially zero value and the phase discrimination signal has a positive value. When the value is the maximum, that is, the workpiece (not shown) on the first conveyor 1 is at the takt start position, and the workpiece (not shown) on the second conveyor 2 is at the takt start position. (not shown) and is at the synchronous position, it is determined that it is the synchronous timing, and a synchronous timing signal is output at the same time. In addition,
Reference numeral 12 denotes a normally open contact 12 interposed in the signal path 13 from the position control section 10 to the second speed control section 6'.
a speed output section, the speed output section 1 having a
Reference numeral 2 indicates that the contact 12a closes in response to the synchronization timing signal from the synchronization detection section 11. Therefore, at the synchronization timing, the speed signal of the position control section 10 is transferred to the second speed control section by closing the contact 12a. 6'.

Therefore, when the second speed control section 6' does not receive the speed signal from the position control section 10 (the second speed control section 6'
When restarting operation after a failure of the conveyor 2, etc.), the set rotation speed signal of the second motor 4' (set speed signal of the second conveyor 2) received from the speed setting section 7,
It has a function of comparing the actual rotation speed of the second motor 4' detected by the speed detection generator 5' and controlling the actual rotation speed of the second motor 4' to match the set rotation speed. Also, when receiving the speed signal of the first conveyor 1 from the position control unit 10 (at the synchronization timing)
In this case, the speed signal of the first conveyor 1 is prioritized over the set rotational speed signal from the speed setting section 7, and the second motor corresponding to the speed of the first conveyor 1 is controlled based on the speed of the first conveyor 1. 4', and controls the rotation speed of the second motor 4' to reach the target rotation speed, thereby synchronizing the speed of the second conveyor 2 with the speed of the first conveyor 1. .

Next, to explain the operation of the above embodiment,
During synchronous operation of the first and second conveyors 1 and 2,
For example, if the second conveyor 2 stops due to a failure, the first conveyor 1
The rotation of the motor 4 continues to operate at a speed corresponding to the set rotational speed of the first speed control section 6. At this time, the synchronization control unit 9 sends a synchronization signal (see Figure 2A) that changes periodically as the workpiece (not shown) on the first conveyor 1 moves, and a phase discrimination signal (see Figure 2B). is output, and the contact 12a of the speed output section 12 is open.

When the second conveyor 2 is restored and restarts its operation, the second conveyor 2 is rotated by the second speed controller 6 independently of the first conveyor 1 by the rotational drive of the second motor 4'. Although the second conveyor 2 starts to operate at a speed corresponding to the set rotation speed of A slight speed difference occurs, and both conveyors 1 and 2 are in an asynchronous operating state. Thereafter, when this operating state continues and the phase discrimination signal reaches the maximum + value and the synchronization signal reaches approximately zero value due to the speed difference between the two conveyors 1 and 2, the synchronization detection section 11
A synchronization timing signal is output from
The speed signal will be output to the second speed control section 6'. As a result, at the synchronized timing, the second conveyor 2 is moved to the first conveyor 1 by feedback control of the second motor 4' by the second speed control section 6' which receives the speed signal from the position control section 10.
The operation will start in synchronization with the following.

Therefore, when the first and second conveyors 1 and 2 are operated synchronously, even if the operation of the second conveyor 2 is stopped, the operation of the first conveyor 1 can be continued, and the operation of the second conveyor 1 can be continued. When the operation of 2 resumes,
Since synchronous operation is automatically started at the synchronization timing, it is easy to start synchronous operation after trouble recovery, and the operating rate of the first conveyor 1 can be improved. Moreover, in the case where the first conveyor 1 is a conveyor such as a conveyor in a painting line where the quality of the workpieces will deteriorate if it stops in the middle of work, the first conveyor 1a
As the specified work is completed by continuing the operation,
Deterioration of work quality can be prevented.

In addition, although the case where the operation of the 2nd conveyor 2 stopped when both conveyors 1 and 2 were synchronously operated was described above, the case where the operation of the 1st conveyor 1 was stopped is also the same as the above.

As explained above, according to the conveyor synchronous operation control circuit of the present invention, when two conveyors arranged in series are operated synchronously, when the operation of one conveyor stops, the operation of the other conveyor is continued, and then When the operation of one conveyor is restarted and the synchronization timing is reached, both conveyors are automatically started in synchronization without any synchronization deviation, which makes it easy to start synchronization. Therefore, the conveyor operating rate can be improved. In addition, it is possible to prevent the quality of the work from deteriorating as the conveyor continues to operate, which is useful for transferring and transferring the work between conveyors arranged in series.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a general schematic diagram, FIG. 2A is a waveform diagram of a synchronizing signal, and FIG. 2B is a waveform diagram of a phase discrimination signal. 1...first conveyor, 2...second conveyor,
4, 4'... Motor (driving means), 8... Synchro transmitting section, 9... Synchro control section, 10... Position control section, 1
1...Synchronization detection section, 12...Speed output section, 12a...Normally open contact.

Claims (1)

[Claims] 1 A synchronized operation control circuit for a conveyor in which two independently driven conveyors are arranged in series and workpieces are delivered and conveyed between the conveyors, and a synchronized transmission that electrically detects the workpiece conveyance position of one conveyor. a synchronization control section that receives the conveyance position signal from the synchronization transmission section and outputs a synchronization signal between both conveyors and a phase determination signal; a position control section that converts the synchronization signal of the synchronization control section into a speed signal; a synchronization detection section that determines synchronization timing using the synchronization signal and phase discrimination signal of the synchronization control section and outputs the synchronization timing signal; A synchronous operation control circuit for a conveyor, comprising: a speed output section that outputs an output to a driving means of the conveyor.