JP2001347391A - Low-cost gas supply system for purging - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-cost gas supply system for purging which enables at a low cost a stable supply of a purging gas, a stable processing operation for cutting or the like, and improvement in quality of the processing. SOLUTION: The system is characterized by the fact that a pipe line 1 composed of an expansion pipe of bellows type which protects the optical path of a laser beam is connected with a gas supply device 2 for purging gas via a flow rate adjusting valve 3, a buffer tank BT and a gas discharging port 6 are provided in the same system as the pipe line 1, an adjusting and controlling means for gas supply which adjusts and controls the supply rate of the purging gas depending on the expansion and contraction strokes of the expansion pipe, further, a detecting means 5 for the amount of residual gas is provide in the buffer tank BT, an ON/OFF control of the gas supply device 2 for purging gas is performed on the basis of the detected result, the valves of strokes in X-axis and Y-axis are converted into the consumption rate of the purging gas, the opening valve of the flow rate adjusting valve 3 is commanded and controlled according to the converted valve, further, the gas supply device 2 for purging gas is controlled according to the discharged amount from the gas discharging port 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

2. Description of the Related Art Conventionally, there is a technique for stabilizing a processing operation by flowing a purge gas into an optical path during a processing operation of a laser processing machine. That is, an inert gas such as clean air or CO ₂ is supplied in order to clean the inside of the optical path, stabilize the laser beam, and prevent intrusion of dust and moisture from the outside air.

For example, a purging gas supply device
There is a case where a purge gas of 00 l / min is always flowing into the optical axis.

[0003]

However, in the case of a front open type (also called a flying optics type) laser beam machine, as in the above-mentioned conventional example, the supplied purge gas is caused to have a bellows-like expansion and contraction along the X-axis and the Y-axis. The gas is discharged from the gas outlet having the filter by the expansion and contraction operation of the pipe. For example, when the expansion and contraction speed of the shaft is 80 m / min, about 2 m
Within seconds, the bellows shrinks and purge gas is discharged,
As a result, after the purging gas is discharged, the gas supply from the supply device becomes insufficient (discharge amount = 42 l / 2 sec, supply amount = 10 l / 2 sec, and 32 l / 2 sec shortage), and 32 l of outside air (O ₂ ) Is sucked from the filter (bellows effect). The concentration of the purge gas is reduced. Instability of processing operations (such as cutting) and occurrence of poor quality. In order to quadruple the supply amount of the purge gas, the gas supply device must be increased in size. If you have a counter bellows, you need a volume of X + Y bellows,
A large space is occupied, and equipment costs and running costs are increased, which causes a problem that these become bottlenecks.

[0004] The present invention has been made in view of the above circumstances, and can achieve a stable supply of a purge gas, stabilize processing operations such as cutting, and further improve quality, and can be realized at a low price. It is an object of the present invention to provide a low-cost purge gas supply system.

[0005]

The present invention can solve the above-mentioned problems by providing the following constitution.

(1) A purging gas supply system at the time of a processing operation of a laser processing machine or the like having an NC device, wherein a pipe formed of a bellows-like telescopic tube for protecting the X-axis and Y-axis optical paths of laser light is provided. It is connected to the purging gas supply device via a flow control valve, and a buffer tank and a gas outlet are provided in the same system of the pipe line, and the supply amount of the purging gas is adjusted according to the amount of expansion / contraction stroke of the expansion / contraction tube. A gas supply amount adjustment control unit for controlling the gas supply amount, a gas remaining amount detection unit is mounted in the buffer tank, and the purging gas supply device is turned on based on a detection result of the gas remaining amount detection unit.
/ OFF control, converts the stroke amounts of the X-axis and the Y-axis into the consumption amount of the purge gas, controls the opening amount of the flow control valve according to the converted value, and further controls the gas discharge port. A low-cost purge gas supply system characterized in that the on / off control of the purge gas supply device is performed in accordance with the amount of gas discharged from the gas supply system.

(2) The buffer tank accommodates a flexible bag made of synthetic resin or the like in a housing, and the bag sucks a purging gas in conjunction with the expansion and contraction of the bellows-shaped expansion and contraction tube. The low cost purging described in the above item (1), characterized in that the gas remaining amount detecting means is configured to function in accordance with the inflation / deflation operation of the bag body, in addition to having a dischargeable structure. Gas supply system.

(3) The low-cost purge gas supply system according to (1), wherein the gas supply amount adjustment control means is a control means for command-controlling the opening amount of the flow rate control valve.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below.

FIG. 1 is an explanatory view showing the configuration of a low-cost type purge gas supply system according to the present invention, FIG. 2 is a view showing the installation of the buffer tank, and FIG. 3 is a control operation of the low-cost type purge gas supply system. FIG. 4 is a flowchart showing an example, and FIG. 4 is a diagram of a purge system in a laser beam path (conventional example).

A description will be given below with reference to the drawings.

A purging gas supply system during a processing operation of a laser processing machine or the like having an NC device, which purges a pipe line 1 consisting of a bellows-shaped telescopic tube for protecting the X-axis and Y-axis optical paths of laser light. It is connected to a gas supply device 2 via a flow control valve 3 and a buffer tank BT and a gas discharge port 6 are provided in the same system as the pipe line 1, for purging according to the expansion and contraction stroke amounts Xst and Yst of the expansion and contraction tube. A gas supply amount adjustment control means for adjusting and controlling the gas supply amount; and a gas remaining amount detection means 5 in the buffer tank BT.
And controls the on / off control of the purging gas supply device 2 based on the detection result of the gas remaining amount detecting means 5, and determines the stroke amounts Xst and Yst of the X-axis and the Y-axis by the consumption amount of the purging gas. The opening amount of the flow control valve 3 is command-controlled in accordance with the converted value, and the purge gas supply device 2 is turned on in accordance with the amount of gas discharged from the gas outlet 6. / OFF control is performed.

In the buffer tank BT, a flexible bag 4a made of synthetic resin or the like is housed in a housing 4, and the bag 4 is purged with a purging gas in conjunction with the expansion and contraction of the bellows-shaped expansion and contraction tube. And the gas remaining amount detecting means (gas remaining amount detecting sensor) 5 functions according to the inflation / deflation operation of the bag body 4.

Further, the gas supply amount adjustment control means is a control means for command-controlling the opening amount of the flow rate adjustment valve 3. It is assumed that all of the above control means are mounted in the NC device.

The operation will be described based on the above configuration and the flowchart of FIG.

When the switch of the apparatus is turned on and the laser processing operation is started, a predetermined type of purge gas is started to be supplied from the purge gas supply apparatus 2 in step S1,
In step S2, the flow control valve 3 is operated, and in the next step S3, the purging gas is stored in the buffer tank BT. In step S4, the buffer tank BT is stored.
It is determined by the gas remaining amount detection sensor 5 whether the gas stock amount in the gas exceeds a predetermined amount. If the result is YES and the gas stock amount is over, an OFF command is issued through the NC device, and the process returns to step S1 to purge Gas supply device stops.

On the other hand, if NO is determined in the step S4, the process proceeds to a step S5 in which the purging gas is supplied and sucked into the X and Y optical axes.
The X-axis and Y-axis stroke amounts Xst and Yst are determined by an NC device, for example, the stroke amount Xst per unit time per hour.
And Yst are monitored, the stroke amounts Xst and Yst are converted into gas consumption amounts, and based on the results, the gas supply amount is returned to step S2 to be adjusted by the flow control valve 3. In step S7, the old purge gas in the optical path is discharged and the new purge gas is discharged by automatically opening and closing the gas discharge port 6, for example, by fully opening the opening of the gas discharge port 6 every 30 minutes. Supply and renew. In the next step S8, the gas remaining amount detection sensor 5 determines whether or not the amount of purge gas discharged is large. An ON command is issued to the supply device 2, and the process returns to step S1 to supply the purge gas. In step S8, if the discharge amount from the gas discharge port 6 is not large,
The machining operation is continued while maintaining a stable state.

The stroke amount Xst and Yst of the X-axis and Y-axis, or the movement amount is replaced by the rotational speed of the drive motor, and the rotational speed is read by an NC device. Via 3, the gas supply amount may be automatically adjusted.

The type of the purge gas is selected from the group consisting of clean air, N ₂ and CO ₂ according to the product or processing conditions.
Needless to say, an inert gas such as the above, or a gas (gas) suitable for other conditions can be freely selected.

[0020]

According to the present invention, the purging gas can be freely sucked / discharged in conjunction with the expansion / contraction operation of the bellows-shaped telescopic tube for protecting the laser beam path, and the bag is mainly made of a bag which can flexibly cope with it. Processing operations such as stable supply and cutting of purge gas by using a buffer tank with a simple structure and controlling the supply amount of purge gas based on the gas remaining amount detection sensor and the stroke amount of the X axis and Y axis. Of the present invention can be improved, and the quality can be improved, and it can be realized at a low price.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of a low-cost type purge gas supply system according to the present invention.

Fig. 2 Installation drawing of the buffer tank

FIG. 3 is a flowchart showing a control operation example of the low-cost type purge gas supply system.

FIG. 4 is a diagram of a purge system in a laser beam path (conventional example)

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe line which consists of an expansion tube 2 Gas supply device for purging 3 Flow control valve 4 Housing 4a Bag 5 Gas remaining amount detection means (sensor) 6 Gas outlet BT Buffer tank Xst X-axis stroke Yst Y-axis stroke

Claims (3)

[Claims] 1. A purging gas supply system during a processing operation of a laser processing machine or the like having an NC device,
A pipe made of a bellows-shaped telescopic pipe for protecting the X-axis and Y-axis optical paths of the laser light is connected to a purge gas supply device via a flow control valve, and a buffer tank and a gas are provided in the same system of the pipe. A discharge port is provided, a gas remaining amount detecting means is installed in the buffer tank, and the purge gas supply device is turned on based on a detection result of the gas remaining amount detecting means.
/ OFF control, converts the stroke amount of the X-axis and the Y-axis into the consumption amount of the purge gas, and adjusts and controls the supply amount of the purge gas according to the converted value. The purge gas supply device is turned on / off according to the amount of gas discharged from the gas discharge port.
A low-cost purge gas supply system configured to perform an OFF control. 2. The buffer tank stores a flexible bag made of synthetic resin or the like in a housing, and the bag sucks and purges gas for purging in conjunction with the expansion and contraction of the bellows-shaped expansion and contraction tube. 2. A low-cost purge gas supply according to claim 1, wherein the gas supply means is configured to be capable of discharging freely, and the gas remaining amount detection means is configured to function in accordance with the inflation / deflation operation of the bag body. system. 3. The low-cost purge gas supply system according to claim 1, wherein said gas supply amount adjustment control means is a control means for command-controlling an opening amount of said flow rate adjustment valve.