JP2583442Y2 - Two-stage stroke pressing mechanism in electric resistance welding machine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-stroke pressurizing mechanism in an electric resistance welder, and more particularly to an electric resistance welder capable of pressing an electrode in two strokes when welding portions have different thicknesses. An object of the present invention is to provide a two-stage stroke pressurizing mechanism in an electric resistance welding machine capable of quickly performing an operation at the time of two-stage stroke pressurization.

[0002]

2. Description of the Related Art Electrode pressurization of an electric resistance welding machine is performed using an air cylinder provided with a predetermined air circuit. However, in recent years, an object to be subjected to electrode pressurization has been provided with a complicated shape such as unevenness,
It is required to perform the electrode pressing stroke in two stages.

[0003] Conventionally, when changing from a large stroke to a small stroke, it is extremely slow, and if it is to be done quickly, an electric control (timer or the like) must be used, and three solenoid valves must be used. Therefore, conventionally, two solenoid valves were used and used at an extremely slow speed.

[0004]

Therefore, the inventors of the present invention have studied various means for enabling the electrode to be pressurized with a rapid two-stage stroke. As a result, it is difficult to quickly perform the second-stage stroke. found.

When trying to increase the speed of the second stroke, it can be inferred that the back pressure applied to the cylinder during pressurization is an obstacle, but it is difficult to release this back pressure in a timely manner.

[0006]

The two-stage stroke pressing mechanism in the electric resistance welding machine according to the present invention includes an electrode pressing cylinder, an internal cylinder provided in the electrode pressing cylinder, and a piston mounted in the internal cylinder. A two-stage stroke pressure port and a welding stroke opening port are formed on both sides of the inner cylinder of the two-stage cylinder, respectively, and a welding stroke is provided between the inner cylinder and the piston. A pressure port is formed, while an air circuit is formed by a two-stage stroke pressure valve, a welding stroke pressure valve, a back pressure exhaust valve at the time of two-stage stroke pressure, and an air operated time delay valve,
The air supplied through a two-stage stroke pressure valve of this air circuit is connected to a two-stage stroke pressure port via an air-operated time delay valve, and the welding stroke pressure valve is connected to a welding stroke pressure port. , Connect to the welding stroke opening port through the back pressure exhaust valve,
Further, at the time of two-stage stroke pressurization, the back pressure exhaust valve is controlled by the air operated time delay valve.

In the electric resistance welding machine of the present invention,
One of the features of the step-stroke pressurizing mechanism is that the control system conventionally used can be inherited as it is.

[0008]

The two-stroke pressurizing mechanism in the electric resistance welding machine of the present invention is constructed as described above, so that the electrode pressurization can be smoothly performed with two-strokes (about four times as fast as usual).
And two-stage stroke pressurization can be performed quickly.

Accordingly, even when the thickness of the object to be subjected to electrode pressurization is not uniform, it is possible to cope with the problem without difficulty, and the welding operation at that time can be performed quickly and accurately.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a two-stage stroke pressing mechanism in an electric resistance welding machine of the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, reference numeral 1 denotes a two-stage stroke pressurizing cylinder in which one of electrodes is attached to the tip of a piston rod 21. The two-stage stroke pressing cylinder 1 includes an electrode pressing cylinder 2, an internal cylinder 3 slidably fitted into the electrode pressing cylinder 2,
Further, a piston 4 fitted in the inner cylinder 3
It is composed of

A two-stage stroke pressure port 5 and a welding stroke release port 6 are formed on both sides of the inner cylinder 3 in the electrode pressure cylinder 2 of the two-stage stroke cylinder 1, respectively. A welding stroke pressurizing port 7 is formed between the piston 4 and the welding stroke pressurizing port 7. Therefore, the piston 4 is operated by sending air from the welding stroke pressurizing port 7, while the internal cylinder 3 is operated by sending air from the two-stage stroke pressurizing port 5. The welding stroke pressurizing port 7 is connected to the rear end of the piston rod 21 and is opened between the internal cylinder 3 and the piston 4. It may be connected and open between the inner cylinder 3 and the piston 4.

An air circuit 11 supplies or exhausts air to each of the ports 5, 6, and 7. The air circuit 11 is provided between the air supply source and the two-stage stroke cylinder 1 and is provided with a two-stage stroke pressurizing valve 12 (solenoid valve), a welding stroke pressurizing valve 13 (solenoid valve), a welding stroke pressurizing valve, and the like. It is formed by a back pressure exhaust valve 14 (air valve) and a pneumatically actuated time delay valve 15 during two-stage stroke pressurization.

In the air circuit 11, a two-stage stroke pressurizing valve 12 connected to an air supply source is connected to a two-stage stroke pressurizing port 5 via an air-operated time delay valve 15. In addition, a welding stroke pressurizing valve 13 connected separately to an air supply source is connected to the welding stroke pressurizing port 7 and connected to the welding stroke opening port 6 via a back pressure exhaust valve 14. I have.

In the air circuit 11, a back pressure exhaust valve 14 connected to the welding stroke opening port 6 and a welding stroke pressurizing valve 13 connected to the welding stroke pressurizing port 7 are each provided with a first air exhaust port 16. It is exhausted from. On the other hand, a welding stroke pressure valve 13 connected to the welding stroke pressure port 7 and a two-stage stroke pressure valve 12 connected to the two-stage stroke pressure port 5
Is rapidly exhausted from the second air exhaust port 17.

The air-operated time delay valve 15
The back pressure exhaust valve 14 is operated by detecting air from the step stroke pressurizing valve 12. At that time welding stroke pressure valve 1
The air coming from 3 to the welding stroke opening port 6 is changed in direction, and is exhausted from the welding stroke pressurizing valve 13 through the second air exhaust port 17.

Although the air-actuated time delay valve 15 is described as being adjustable or variable in the drawing, the two-stage stroke pressurizing cylinder 1 of each electric resistance welding machine is shown in FIG.
By selecting one according to the length or the like, one that cannot be adjusted in time can be used. In such a case, there is no problem such as trouble in adjusting the time of the air-operated time delay valve 15 or poor adjustment during use.

Hereinafter, 2 in the electric resistance welding machine of the present invention will be described.
The operation of the stepped stroke pressing mechanism will be described.

FIG. 2 shows a state in which the electrodes are open. The air supplied from the air supply source passes through the pipe a from the welding stroke pressurizing valve 13, passes through the pipe b via the back pressure exhaust valve 14, and returns from the welding stroke release port 6 to the two-stage stroke cylinder 1. Enter the chamber and open the electrodes.

When the direction of the welding stroke pressurizing valve 13 is changed in this state, air enters the internal cylinder 3 through the pipe c, and the piston 4 of the internal cylinder 3 is moved to the left as shown in FIG. Move to close. At this time, the air in the return working chamber passes through the pipe b to the back pressure exhaust valve 14 and is discharged into the atmosphere from the first air exhaust port 16.

Next, after the electrode is opened, when the thickness of the object to be subjected to electrode pressurization is large, air is further supplied from the welding stroke opening port 6 to the return working chamber of the two-stage stroke cylinder 1 in the same manner as described above. To open the electrode. On the other hand, the air in the air working chamber between the electrode pressurizing cylinder 2 and the internal cylinder 3 passes from the two-stage stroke pressurizing port 5 to the two-stage stroke pressurizing valve 12 through the pipe e, and the second air exhaust is performed. It is released from the mouth 17 into the atmosphere.
In this way, the inner cylinder 3 is moved rightward together with the piston 4 as shown in FIG.

Thereafter, when air is supplied from the pipe d,
At the same time as air enters the air-operated chamber from the two-stage stroke pressurizing port 5 through the line e from the two-stage stroke pressurizing valve 12, the pressure is also transmitted to the air-operated time delay valve 15 through the line f. Sent. In the pneumatically operated time delay valve 15, pressure is always supplied to the p port through the pipe g. However, when a signal is sent to the A port, a signal is sent from the S port after a certain time (0 to several tens of seconds). .

Therefore, a certain time after the signal is sent through the line f, a signal air is output to the line h, which activates the back pressure exhaust valve 14. Then, the air returning from the pipe b to the working chamber is changed in direction, and the back pressure exhaust valve 1
4, the air is rapidly exhausted from the first air exhaust port 16, and the air is rapidly exhausted, and the operation at the time of the two-stage stroke pressurization is performed very quickly. Return to.

The subsequent operation at the time of pressurizing the electrode to close the space between the electrodes by moving the piston 4 of the inner cylinder 3 to the left is as described above.

[0025]

[Effect of the Invention] The two-stage stroke pressurizing mechanism in the electric resistance welding machine of the present invention is configured as described above, so that the electrode pressurization can be smoothly performed with two-stage stroke (about four times as fast as usual). It is possible to perform the two-stage stroke pressurization quickly.

Therefore, even when the thickness of the object to be subjected to electrode pressing is not uniform, it is possible to cope with the problem without difficulty, and the welding operation at that time can be performed quickly and accurately.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of a two-stage stroke pressing mechanism in the electric resistance welding machine of the present invention.

FIG. 2 is an air circuit diagram when an electrode is opened.

FIG. 3 is an air circuit diagram when an electrode is pressed.

FIG. 4 is an air circuit diagram when a two-stage stroke is released.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Two-stage stroke pressure cylinder 2 Electrode pressure cylinder 3 Internal cylinder 4 Piston 5 Two-stage stroke pressure port 6 Welding stroke release port 7 Welding stroke pressure port 11 Air circuit 12 Two-stage stroke pressure valve 13 Weld stroke pressure valve 14 Back pressure exhaust valve 15 Air-operated time delay valve 16 First air exhaust port 17 Second air exhaust port a, b, c, d, e, f, g, h Pipe

Claims (1)

(57) [Scope of request for utility model registration] 1. A two-stage stroke cylinder comprising an electrode pressurizing cylinder, an internal cylinder provided in the electrode pressurizing cylinder, and a piston mounted in the internal cylinder.
A two-stroke pressure port and a welding stroke release port are formed on both sides of the inner cylinder of the two-stroke cylinder, respectively, and a welding stroke pressure port is formed between the inner cylinder and the piston.
An air circuit is formed by a step stroke pressurizing valve, a welding stroke pressurizing valve, a back pressure exhaust valve when pressurizing a two-step stroke, and an air operated time delay valve, and air supplied through the two-step stroke pressurizing valve of this air circuit Is connected to a two-stage stroke pressurizing port via an air-operated time delay valve, a welding stroke pressurizing valve is connected to a welding stroke pressurizing port, and a welding stroke opening port is connected via a back pressure exhaust valve. A two-stroke pressurizing mechanism in an electric resistance welding machine, wherein the back-pressure exhaust valve is controlled by the air-operated time delay valve when the two-stroke is pressurized.