JPH05161867A - Surface treating method - Google Patents

Abstract

PURPOSE:To prevent the elongation of a hoist rope which causes a jig to move downwards excessively to bring work into contact with a member in a treating tank when the jig suspended from a hanger by the rope connected to a hoist mounted on the hanger is lowered to immerse the work retained by the jig in the treating tank. CONSTITUTION:When a jig 4 is lowered at a part of a treating line without treating tank, e.g. a pay-off station 18 at the end of the line, a rope 13 is inspected for the possible elongation following the procedure as mentioned below: When the jig 4 is lowered and detected to reach a predetermined reference position by a limit switch 29, unwinding of the rope from a hoist is stopped to detect its rotational phase. When the detecting phase and a predetermined phase are compared and the difference therebetween is great, the rope 13 is replaced with the new one and when the phase difference is within the allowable range, the unwinding of the rope from the hoist is continued for later work immersion until the detecting phase is reached, at which point the hoist is controlled to stop the lowering of the jig in the reference position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface treatment method for immersing a workpiece such as an automobile body in a treatment tank to surface the workpiece.

[0002]

2. Description of the Related Art Conventionally, as a surface treatment method of this kind, according to Japanese Patent Laid-Open No. 3-178358, a hanger moving along a processing line is connected to a hoist equipped with a jig for holding a work. It is lifted up and down via a cord to be rotatably suspended around a horizontal axis, and the work is immersed in the processing tank provided in the processing line by lowering the jig, and the workpiece is also processed through the jig in the processing tank. It is known that the workpiece is surface-treated by rotating the workpiece.

[0003]

In the above-mentioned one, the cords are extended with the lapse of time so that the jig is lowered to a position lower than a predetermined lowered position. During the movement, the work may come into contact with members such as pipes and electrodes arranged at the bottom of the processing tank.

In view of the above points, an object of the present invention is to provide a surface treatment method capable of monitoring the elongation of a cord and preventing the occurrence of the above problems.

[0005]

[Means for Solving the Problems] In order to achieve the above object,
According to the present invention, a hanger that moves along a processing line is provided with a jig that holds a workpiece so that the jig can be moved up and down via a rope connected to a hoist mounted on the hanger so that the jig can be lifted and lowered. Inspection for inspecting the presence or absence of elongation of the cord in the state where the jig is lowered in the part of the processing line other than the place where the treatment tank is placed in the method of performing the surface treatment by immersing the work by lowering the jig in the treatment tank It is characterized by executing the process.

[0006]

When the hanger is moved to the above-mentioned portion of the processing line, the cord is unwound from the winding machine and the jig is lowered in the same manner as when the work is immersed, and the presence or absence of elongation of the cord is inspected. Then, when the cord is extended, appropriate measures such as reducing the amount of the cord fed out when the work is dipped thereafter or replacing the cord are taken so that the position of the jig can be adjusted when the work is dipped. Don't fall too low. In addition, if the inspection step is performed when the workpiece is loaded or discharged at the loading station at the start end of the processing line or the dispensing station at the end of the processing line, the jig can be moved up and down only for inspection. This is advantageous in improving work efficiency and space efficiency because it is unnecessary to provide a station dedicated to the inspection on the processing line.

By the way, in the inspection process, the winding machine may be fed and rotated to a predetermined set phase, and the amount of deviation of the descending position of the jig from the reference position at this time may be measured to detect the elongation of the cord. This is possible, but this requires an expensive measuring instrument that linearly measures the position of the jig. On the other hand, the winding machine is fed and rotated to lower the jig to a predetermined reference position corresponding to the lowered position when the work is immersed, and the rotation phase of the winding machine at this time is detected, and this detection phase is set to the reference position. Compared with the preset phase as the corresponding rotation phase, when the rope is extended, the detection phase does not match the set phase, so the elongation of the rope can be detected.In this case, the rotation phase of the hoisting machine is the same as that of the hoisting machine. Since it can be detected by the originally installed control encoder, only a simple detector such as a limit switch for detecting that the jig is lowered to the reference position needs to be provided, which is cost effective. Further, with this one, when the work is immersed in the processing tank, the jig rotation during the work immersion is performed simply by stopping the feeding rotation of the winding machine when the rotation phase reaches the detection phase. The descending position of can always be the reference position regardless of the elongation of the cord.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, reference numeral 1 denotes a treatment line for subjecting an automobile body W, which is a workpiece, to a surface treatment.
Is provided with a loop-shaped conveyor rail 2 above which a self-propelled hanger 3 is supported, and a jig 4 for holding a work W is hung up and down on the hanger 3 so that the processing line 1 The vehicle body W was immersed in the plurality of treatment tanks 5 provided in the order, and subjected to various surface treatments such as washing with water, degreasing, chemical conversion treatment, and electrodeposition.

As shown in FIGS. 2 and 3, the hanger 3 has a horizontal support frame 8 attached to the lower end of a hanger frame 7 which is rotatably suspended on the conveyor rail 2 via rollers 6. The hanger 3 is self-propelled along the conveyor rail 2 by the drive unit 11 equipped with the motor 10 controlled by the controller 9.

The jig 4 is formed to be long in the lateral direction so as to hold the vehicle body W sideways, and a pair of sprockets 12 and 12 are fixedly provided at both ends thereof on the same horizontal axis. Chains 13 and 13 each made of a chain are respectively wound around the both sprockets 12 and 12, and a pair of hoisting machines 14 and 14 are mounted on the hanger 3, and one hoisting machine 14 is provided with both ropes 13 and 13. One end and the other hoist 14
And the other ends of both cords 13 and 13 to the support frame 8 respectively.
Connected via the upper guide member 15, both hoisting machines 14,
The jigs 4 are lowered or raised by rotating 14 together in the unwinding direction or the winding direction to move the vehicle body W into and out of the processing tanks 5, and further, the hoisting machines 14 and 14 are moved in opposite directions. By rotating the jig 4, the vehicle body W can be rotated around the horizontal axis in the vehicle length direction. Further, in order to prevent the jig 4 from swinging when moving up and down or rotating, the processing tank 5
A pair of guide frames 16, 16 that engage with the shaft portion 12a of each sprocket 12 are erected on both ends of the sprocket 12, while the shaft portions 12a are also engaged with both end portions of the support frame 8 of the hanger 3. A pair of guide frames 17 are vertically provided to prevent the jig 4 from swinging during transportation.

The vehicle body W is loaded into the jig 4 at a loading station (not shown) at the start end of the processing line 1, and the jig 4 is loaded at the dispensing station 18 at the end of the processing line 1.
As shown in FIGS. 4 and 5, the dispensing station 18 is provided with a lifter 21 that is moved up and down along the support column 20, and after the jig 4 is lowered, the lifter is lifted. 21 is lifted by the cylinder 22 via the chain 23 to lift the vehicle body W from the jig 4, and the support arm 26 extended from the dispensing carriage 25 provided on the track frame 24 extending in front of the dispensing station 18 is attached to the vehicle body W. After entering the lower side, the lifter 21 is lowered and the vehicle body W is placed on the support arm 26.
Was conveyed to the next step.

Further, machine frames 27, 27 are erected on both sides of the payout station 18, and a guide frame 28 similar to the guide frame 16 erected on the processing tank 5 is attached to each machine frame 27,
At the lower end of the guide frame 28, a limit switch that comes into contact with the shaft portion 12a and operates when the jig 4 is lowered to a predetermined reference position corresponding to the lowered position when the vehicle body W is immersed in the processing tank 5. A detector 29 consisting of
In response to the signal from, the feeding rotation of the winding machine 14 was stopped, and the elongation of the cord 13 was inspected. In this inspection, an encoder (not shown) attached to the hoisting machine 14 detects the rotational phase of the hoisting machine 14 when the rotation is stopped, and the jig 4 is lowered to the reference position in a state where the cord 13 is not extended. This is performed by comparing the preset phase, which is the rotation phase of the hoisting machine 14, with the detection phase. The details are as shown in FIG. 6, and the hanger 3 is the dispensing station 1.
When the hoisting machine 14 is moved to 8 and stopped, the hoisting machine 14 is unreeled and rotated to lower the jig 4 (S1, S2), and when the jig 4 is lowered to the reference position and the detector 29 operates, the hoisting machine 1
4 is stopped (S3, S4). Then, after detecting the rotational phase of the hoisting machine 14 at this time and obtaining the phase difference ΔΘ between the detected phase and the set phase, it is judged whether or not ΔΘ≈Ο (S5, S6), and Δ When Θ≈Ο is not satisfied, it is determined whether or not ΔΘ is within the allowable range (S7), and when it is outside the allowable range, an alarm for instructing replacement of the cord 13 is activated (S8).
On the other hand, when ΔΘ is within the allowable range, the feeding rotation stop phase of the hoisting machine 14 when the vehicle body W is immersed in the processing tank 5 is corrected to the above detection phase (S9). Thus, even if the cord 13 is stretched, the vehicle body W can be immersed in the processing tank 5 at a constant level, and even if the vehicle body W is rotated, a pipe or an electric wire (not shown) provided at the bottom of the processing tank 5 is provided. The body W is used for the members such as electrodes.
Will not abut.

In the above embodiment, the payout station 1
Although the elongation of the cord 13 is inspected at 8, it is also possible to inspect at the feeding station by the same procedure as above.

[0014]

As is clear from the above description, according to the invention of claim 1, it is possible to detect the elongation of the cord early and take appropriate measures. Further, according to the invention of claim 2, For example, the elongation of the rope can be inspected by using the jig lowering at the loading station and the dispensing station, and the work efficiency and space efficiency can be improved.

Further, according to the invention of claim 3, the elongation of the cord can be inspected without using a complicated detector, and according to the invention of claim 4, the jig of the jig when the cord is elongated is inspected. The lowered position can be easily corrected and the control becomes easy.

[Brief description of drawings]

FIG. 1 is a side view of an example of a processing line to which the method of the present invention is applied.

2 is an enlarged sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along the line III-III in FIG.

FIG. 4 is an enlarged side view of the dispensing station.

FIG. 5 is a front view seen from the direction of arrow V in FIG.

FIG. 6 is a flowchart showing an inspection process procedure.

[Explanation of symbols]

W Car body (work) 1 Processing line 3 Hanger 4 Jig 5 Processing tank 13 Rope 14 Winding machine 18 Discharging station

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Total Ishii 1-10 Shin-Sayama, Sayama-shi, Saitama Prefecture Honda Engineering Co., Ltd.

Claims (4)

[Claims] 1. A hanger that moves along a processing line,
A jig for holding the work is hung up and down through a rope connected to a hoist mounted on the hanger, and the work is immersed in the processing tank provided in the processing line by descending the jig to surface the surface. In the method of performing treatment, a surface treatment method is characterized in that an inspection step of inspecting the presence or absence of elongation of a cord is performed in a state in which a jig is lowered in a portion of a treatment line other than an arrangement position of a treatment tank. 2. The inspection step is executed when a work is loaded or discharged in a state where a jig is lowered at a loading station at a starting end of a processing line or a dispensing station at a terminating end of the processing line. The surface treatment method described. 3. In the inspecting step, the winding machine is fed and rotated to lower the jig to a predetermined reference position corresponding to the lowered position when the work is immersed, and the rotation phase of the winding machine at this time is detected, The surface treatment method according to claim 1 or 2, wherein the detection phase is performed by comparing it with a preset phase that is predetermined as a rotation phase corresponding to the reference position. 4. The method according to claim 3, wherein after the inspection step is performed, when the work is immersed in the processing tank, the feeding rotation of the winding machine is stopped when the rotation phase reaches the detection phase. Surface treatment method.