JPH01294114A - Synchronization of overhead conveyor and device therefor - Google Patents

Abstract

PURPOSE:To suppress the position deflection from a conveyor by continuing the operation of a part mounting device and supplying a conveyor speed signal until the conveyor speed signal lowers below a standard level in the emergency stop, in the titled device for an assembled vehicle. CONSTITUTION:When an emergency stop signal (e) is inputted into a motor driving circuit 13, the drive of a motor 12 is suspended, and an operation signal (d) diminishes. Then, a comparison circuit 26 outputs an operation continuation signal (f). A conveyor body 11 continues shift by inertia, and the conveyor speed signal (b) on the level corresponding to a motor control circuit 24 is supplied, and a dolly 21 is travelled synchronously in parallel. When the level of the conveyor speed signal (b) becomes lower than a standard level (a), the motor control circuit 24 stops operation, and the parallel drive is suspended. With this constitution, the position deflection from the overhead conveyor of a part mounting device can be suppressed.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is characterized in that a motor control circuit that receives a conveyor speed signal as input causes the conveyor to be synchronously parallelized in a predetermined section of the conveyor path and then returned to its original position. This invention relates to a synchronization method and device for driving the component mounting device in parallel in a synchronous state against inertial movement during an emergency stop in an overhead conveyor that suspends a reciprocating component mounting device or an attached assembly vehicle. .

[Conventional technology]

In order to synchronize and parallelize this type of component mounting device or an attached Ohahead conveyor, the component loading device is driven by a motor control circuit that receives as input the conveyor speed signal detected by the speed sensor of the drive motor of the Overhecht conveyor. I'm letting you do it. Further, for safety reasons, this running drive is only possible while the overhead conveyor is in operation.

[Invention or problem to be solved]

However, if the overhead conveyor is brought to an emergency stop while the component loading equipment is running in parallel, it will run with inertia because it is carrying a larger load, and the loading equipment will be delayed due to its position, causing the synchronization relationship to break down. There is a problem that the work becomes difficult if the position is not adjusted at the time of operation or re-operation.

In such a case, closed-loop servo control can be considered, in which position sensors are provided in each of the component mounting device and the overload conveyor, and the difference between the detection signals of the two is used as a control signal, but this cannot be constructed at low cost.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a method and apparatus for synchronizing an overhead conveyor of the type described at the beginning, which suppresses displacement of a component mounting device from an overhead conveyor during an emergency stop by adding a simple circuit.

[Means to solve the problem]

In order to achieve this object, the method of the present invention, as shown in FIG. The motor control circuit (24) for the component mounting device (20) is activated and a conveyor speed signal is supplied while detecting the rotation and further detecting the rotation from the time of emergency stop. It has become.

A device for implementing this method starts operation in response to an emergency stop signal e of the overhead conveyor (10),
Level comparison means (2) for continuing operation of the motor control circuit (24) for the component mounting device (20) until it is detected that the conveyor speed signal level falls below the reference level a.
6, 27).

(Function) During an emergency stop, the motor control circuit (24) waits until the conveyor speed signal falls below the reference level a, that is, until the speed decreases to a predetermined level even if the inertia of the overhead conveyor (10) fluctuates. is activated, and the component mounting device (20) runs synchronously in accordance with the conveyor speed. Even if the inertial speed of the overhead conveyor (10) falls below the speed corresponding to the reference level a and the synchronization relationship collapses, only a slight positional shift will occur because the speed has decreased. Further, after the temperature falls below the reference level a, the motor control circuit (24) becomes inactive, eliminating the possibility of malfunction and ensuring safety.

The level comparison means (26, 27) causes the motor control circuit (24) to continue operating based on the conveyor speed signal corresponding to inertia running, and disables the motor control circuit (24) when the signal falls below the reference level a. to stop parallel drive.

(Embodiment of the Invention) FIGS. 2 and 3 show an example of a circuit device implementing the synchronization method of the present invention.

In Figure 2, 10 is an overheight conveyor,
A chain-type conveyor body 11 that suspends an assembly vehicle 1 on which parts are assembled, a motor 12 that drives this body, and this motor is driven to open when a driving signal d is input, and stops driving when an emergency stop signal e is input. and a tacho generator 14 as a speed sensor that rotates in conjunction with the motor 12 and sends out a conveyor speed signal at a level corresponding to the speed of the motor 12.

Reference numeral 20 denotes a component mounting device, which is a lift that mounts the rear axle 2 as an assembly component and travels on a rail so as to move from origin position A back to origin position A via synchronization start position B and return position C. A trolley 21 with a mechanism, a motor 22 equipped with a negative feedback tacho generator 23 that drives the trolley, and a conveyor speed signal from the tacho generator 14 are input to drive and control the motor 22 under the negative feedback of the tacho generator 23. A motor control circuit 24 is provided. That is, this motor control circuit operates at one position A, B and C.
The origin position A is determined in response to the detection signal of the position sensor belonging to
When the conveyor main body 11 reaches the synchronization start position and the sensor 15 detects that the conveyor main body 11 has reached the synchronization start position, it returns to the position C at a speed corresponding to the conveyor speed signal.
Then, sequence control is performed to make them parallel and further return to the origin position 21tA.

Such a motor control circuit 24 itself is well known, but according to the present invention, when the emergency stop signal e is input, it starts operating and outputs the operation continuation signal f to the OR gate 27, and the conveyor speed signal is almost at the normal level. A comparator circuit 26 is added that stops outputting the operation continuation signal f when the voltage drops below the half-matching reference level a.

The operation is as follows.

In normal operation, the bogie 2 equipped with the rear axle 2]
is running from the origin position IA to the synchronization start position 6B and waiting, and when the detection signal of the position sensor 15 is supplied, the motor control circuit 24 receives a speed signal of the tachogenerator 14 that is sufficiently larger than the reference level a. Supplied. Thereby, the motor 22 drives the cart 21 in parallel at the corresponding synchronous speed. At the same time, the lift equipment also operates.

When the emergency stop signal e is supplied to the motor drive circuit 13 for some reason, the drive of the motor I2 is stopped and the operation signal d disappears, but instead the comparison circuit 26 starts the operation jIt.
Outputs a continuation signal f. The conveyor main body 11 continues to move due to inertia, and a conveyor speed signal of a corresponding level is supplied to the motor control circuit 24, so that the carts 21 are synchronously parallel. During this time, the conveyor moves by inertia by about 1,301 degrees, for example, and when it reaches the reference level a, the speed is almost halved. It becomes only a few layers. That is, as shown in FIG. 3, the positional deviation D that conventionally occurred between the arm of the rear axle 2 and the rear floor side member of the assembled vehicle 1 becomes small. Moreover, after this point, the driving continuation signal f disappears, so one bogie 21
Accidental running of the vehicle is also prevented.

In the above-mentioned embodiment, the motor control circuit for the component mounting device, including the level comparison means, can also be configured by a CPU.

〔Effect of the invention〕

As described above, according to the present invention, since the component mounting device synchronizes and parallels the inertia running after the overhead conveyor stops in an emergency,
At that time, the mutual positional deviation becomes small, and the work can be continued as it is, or the work can be started immediately upon restarting. Also,
After parallel to this inertia running, the component mounting device becomes inoperable, so safety is ensured regardless of the addition of functions. Since it can be configured by adding a small number of circuits, there is almost no increase in cost.

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating the present invention in detail, FIG. 2 is a diagram showing a schematic configuration of an overhead conveyor including a parallel synchronization device according to an embodiment for carrying out the method of the present invention, and FIG.
The figure is a diagram explaining the operation of the same embodiment.

Claims (1)

[Scope of Claims] 1) A component mounting device that is synchronously driven in parallel in a predetermined section of the conveyor path by a motor control circuit that receives the conveyor speed signal as input while the conveyor is in operation, and then driven back to the original position. A synchronization method for driving the component mounting device in parallel in a synchronized state with respect to movement due to inertia during an emergency stop of the conveyor in an overhead conveyor for suspending an assembly vehicle including an attached vehicle, the method comprising: Detecting that the conveyor speed signal level falls below a reference level that is smaller than the normal level, and continuing the operation of the motor control circuit to control the conveyor speed signal from the time of the emergency stop until the level falls below a reference level. A method for synchronizing an overhead conveyor, characterized in that: 2) The motor control circuit of the component mounting device starts operating in response to the emergency stop signal of the overhead conveyor until it detects that the conveyor speed signal level falls below a reference level that is smaller than the normal level. A synchronization device for an overhead conveyor carrying out the method according to claim 1, characterized in that it is provided with level comparison means for continuing the operation of said motor control circuit.