JP2003266272A - Working fluid supply device for machine tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a working fluid supply device for a machine tool capable of preventing clogging of a back-up filter when a filter of a filtration device is not broken and detecting its breakage speedily when it is broken. <P>SOLUTION: This working fluid supply device is provided with the filtration device 5 for receiving used working fluid and letting clean working fluid flow out into a first clean tank 9 through the filter 7, the back-up filter 11 provided between the first clean tank 9 and a second clean tank 13, a jet nozzle 25 for working fluid for washing the back-up filter 11, and a liquid level gage 27 for detecting that a liquid level of the first clean tank 9 rises up to a predetermined liquid level. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention separates a used machining fluid mixed with machining waste collected from a machining section into machining waste and machining fluid, and supplies the cleaned machining fluid again to the machining section. The present invention relates to a machining fluid supply device for a machine tool.

[0002]

2. Description of the Related Art In a machine tool such as a milling machine, a machining center, a grinder, an electric discharge machine, a machining liquid is supplied to a machining part of a work to cool the tool and the work, and machining scraps generated by machining are discharged from the machining part. Processing is progressing while removing. Then, the used machining fluid containing machining chips is collected in the machining fluid tank of the machining fluid supply device, the machining chips are separated, and the cleaned machining fluid is supplied again to the machining unit and the machining tool. It circulates to and from the liquid tank. A first conventional technique for separating processing waste from a used processing liquid is disclosed in Japanese Patent Publication No. 2-44564. This involves immersing the filter drum around which the filter is wound in the used working fluid and rotating it, and passing the clean working fluid that has passed through the filter and entered the filter drum to the external clean tank through the inside of the rotary bearing part of the filter drum. It is a filtering device with a structure that flows out.

As a second conventional technique, Japanese Patent Laid-Open No. 7-472
There is a membrane separation device disclosed in Japanese Patent No. 36. This is because when the fluid to be processed is filtered by passing through the first separation membrane (filter) and the second separation membrane having a slightly coarse mesh, damage to the first separation membrane occurs before the second separation membrane. It is possible to detect and know the pressure increase in the above or the flow rate decrease in the latter stage of the second separation membrane. As a third conventional technique, there is a solid-liquid separation device disclosed in Japanese Utility Model Laid-Open No. 62-79509. In this, a disc-shaped screen (filter) is rotatably installed at the boundary between the dirty liquid tank and the clean liquid tank, and the purified liquid is ejected onto the liquid surface of the disc-shaped screen while being rotated by a motor. Then, the back washing is performed.

[0004]

The above-mentioned first prior art filtering device is often used in machine tools. If the filter wound around this filter drum is damaged, the processing waste will enter the clean tank and be supplied to the machine tool.Therefore, a safety measure is usually taken by installing a backup filter after the filtering device. .

An example of such a safety measure is the second conventional technique, in which the backup filter (second separation membrane) is clogged due to the damage of the filter (first separation membrane) of the filtration device, and the backup caused thereby. The filter breakage of the filter is detected by detecting the pressure increase in the front stage of the filter or the flow rate decrease in the rear stage. However, the purified working fluid that has passed through the filter of the filtering apparatus also contains minute impurities of various shapes, which may catch the eyes of the backup filter depending on the posture of the minute impurities. Then, the mesh in this portion becomes narrower, and the minute impurities are more easily caught, and after several hours or days, the minute impurities adhere to the entire surface of the backup filter in the form of sludge. Then, the filter of the filtering device is not damaged, but it is detected that the filter is damaged, and there is the inconvenience of giving a false alarm. In order to prevent this, it is necessary to regularly clean the backup filter and maintain it in a state where minute impurities are not attached. That is, there is a problem that it takes time and a dead time is generated to temporarily stop the circulation of the working fluid.

When the backup filter is back-washed as in the third prior art, the clogging caused by minute impurities is eliminated, but large processing dust that tends to be scratched by the backup filter when the filter of the filtering device is damaged is also pushed back. It takes a long time for the backup filter to become clogged, which delays the detection of essential filter damage. The present invention has been made in view of such a problem. When the filter of the filtering device is not damaged, the backup filter is not clogged normally, and when the filter of the filtering device is damaged, the damage is detected quickly. It is an object of the present invention to provide a machining fluid supply device for a machine tool that can be used.

[0007]

Therefore, the machining fluid supply device for a machine tool of the present invention separates the used machining fluid mixed with the machining waste collected from the machining section into the machining waste and the machining fluid, and the separation is performed. In the machining fluid supply device of the machine tool that supplies the machining fluid to the machining section, the machining fluid that has been used is received, the machining debris that has entered through the filter is separated, and a clean machining fluid is discharged to the first clean tank. And a second storage device for storing a clean working fluid to be supplied to the first clean tank and the working section.
A backup filter provided at the boundary with the clean tank and having the same or rough surface as the filter of the filtration device, a liquid level sensor for detecting the working liquid level of the first clean tank, and the backup filter And a jet means for jetting a fluid toward the second clean tank from the first clean tank.

A fluid is ejected from the first clean tank toward the second clean tank toward the backup filter. So-called normal cleaning is performed against reverse cleaning. Since the jet means for cleaning the backup filter in the normal direction is provided, minute impurities are not forcibly caught in the backup filter, and are forced to flow downstream. Even if minute impurities are supplied to each part of the machine tool, they have a size that causes no problem. Therefore, when the filter of the filtration device is not damaged, it is necessary to erroneously detect that the backup filter is clogged like sludge and the filter of the filtration device is damaged, or to perform regular cleaning work of the backup filter manually. Disappears.
In addition, when the filter of the filtration device is damaged, large processing chips are caught on the backup filter, so even if the cleaning means is used for normal cleaning, large processing chips will not pass through the backup filter. Clogging occurs and the liquid level sensor detects damage to the filter of the filtration device.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a principle sectional view of an embodiment of a machining fluid supply device for a machine tool of the present invention. The used machining fluid mixed with machining waste from the machine tool is the machining fluid tank 1
Flows into the dirty tank 3 at the right end of. The used processing liquid that has flowed into the dirty tank 3 is filtered, for example, by passing through the filter 7 of the filtering device 5 as shown in the above-mentioned first conventional technique. A configuration may be adopted in which the dirty tank 3 is not provided, and the dirty liquid is directly introduced from the machine tool into the machining liquid receiving port of the filtering device 5.

The clean processing liquid, which is obtained by separating the processing wastes and filtered by the filter device 5, flows into the first clean tank 9. The machining liquid flows into the second clean tank 13 through the backup filter 11, is sucked up by the pump P provided in the second clean tank 13, and is supplied to the machine tool through the pipe 15. The pump P is driven by the motor M1.

The backup filter 11 is in the shape of a disk, and the circumferential portion of the backup filter 11 is rotatably sealed and supported by a support 17, and a pulley 19 provided on the central shaft and a rotating shaft of a motor M2 provided outside. It is rotated at a predetermined rotation speed by the belt transmission means 23 hung between the pulley 21 and the pulley 21. The mesh of the backup filter 11 is set to be equal to or coarser than the filter 7 of the filtering device 5. The jet nozzle 25 provided on the side of the first clean tank 9 jets the clean machining liquid branched and supplied from the pipe line 15 to clean the backup filter 11 directly. The jet nozzle 25 may be provided on the liquid surface and may jet a clean machining liquid onto the liquid surface portion of the backup filter 11 for normal cleaning. Further, compressed air may be jetted instead of the clean working liquid. Further, the backup filter 11 may have a rectangular shape, for example, and may be fixed in the processing liquid tank 1 and provided with a large number of jet nozzles 25 so that the entire mesh surface of the backup filter 11 can be cleaned normally. A liquid level gauge 27 for detecting that the liquid level of the first clean tank 1 has reached a predetermined liquid level is provided, and the output thereof is connected to the notification means 29.

Next, the operation of the machining fluid supply apparatus for this machine tool will be described. Even if the filter 7 of the filtering device 5 is not damaged and the filtering action is performed normally, minute impurities of various shapes are mixed in the cleaned working fluid. The minute impurities have a size that causes no problem even if they are supplied to the machining liquid nozzle of the machine tool or the through spindle coolant device.
Therefore, it is not necessary to further filter this working fluid. However, if the minute impurities are fine and long, bifurcated, or curled, they may be caught on the mesh of the backup filter 11. As described above, this may cause clogging of the entire surface of the backup filter 11. Nozzle 2 for ejecting machining fluid
It is ejected from No. 5 to prevent this clogging. Even if minute impurities try to be scratched by the mesh of the backup filter 11, they are forcibly pushed toward the second clean tank 13 by the force of the jetted machining liquid. Since the backup filter 11 is rotating, the entire surface is evenly cleaned. Therefore, there is no need to interrupt the operation of the machine tool and manually wash the backup filter 11. In this case, the liquid level of the first clean tank 9 does not rise above the predetermined position, the liquid level gauge 27 operates, and no false alarm is issued regarding the breakage of the filter 7 of the filtering device 5.

When the filter 7 of the filtering device 5 is damaged and a large processing waste flows into the first clean tank 9, the processing waste is caught on the backup filter 11. A backup filter 1 that ejects the machining fluid from the ejection nozzle 25
Even if 1 is cleansed normally, since the processing waste cannot be pushed out toward the second clean tank 13 because the processing waste is large, the backup filter 11 is clogged in a short time. Then, the liquid level gauge 27 is activated to notify the notifying means 29 of the damage of the filter 7 of the filtering device 5, an alarm is issued, and the machine tool is automatically stopped. If the backup filter 11 was backwashed as in the third conventional technique, the large processing waste caught on the backup filter 11 is pushed back into the first clean tank 9, and the clogging of the backup filter 11 is delayed. It takes a long time to operate the position indicator 27. That is, by directly cleaning the backup filter 11 with the jet nozzle 25, it is possible to quickly detect damage to the filter 7 of the filtering device 5.

[0014]

As described above, according to the machining fluid supply apparatus for a machine tool of the present invention, a backup filter can be backed up in a normal state where the filter of the filtration apparatus is not damaged due to a simple construction of cleaning the backup filter in a normal manner. When the filter of the filter is damaged, the filter is not clogged, and the damage can be quickly detected.

[Brief description of drawings]

FIG. 1 is a principle cross-sectional view of an embodiment of a machining fluid supply device for a machine tool of the present invention.

[Explanation of symbols]

1 ... Processing liquid tank 3 ... Dirty tank 5 ... Filtration device 7 ... Filter 9 ... First clean tank 11 ... Backup filter 13 ... Second clean tank 25 ... Jet nozzle 27 ... Liquid level gauge 29 ... Notification means

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3C011 BB31                 4D026 BA01 BB01 BB05 BC39 BE01                       BE06 BE11 BF01 BF09 BF10                 4D064 AA23 BM28 BM34 BM37

Claims (3)

[Claims] 1. A machining fluid supply device for a machine tool, which separates a used machining fluid mixed with machining waste recovered from a machining section into machining waste and machining fluid, and supplies the separated machining fluid to the machining section. In, a filtering device that receives the used processing liquid, separates the processing waste mixed through the filter, and discharges the clean processing liquid to the first clean tank, and supplies it to the first clean tank and the processing unit. A backup filter, which is provided at the boundary with the second clean tank for storing the clean working fluid and has the same or coarse mesh as the filter of the filtration device, and a liquid for detecting the working fluid level of the first clean tank. A machining fluid supply device for a machine tool, comprising: a surface position sensor; and jet means for jetting a fluid toward the backup filter from the first clean tank toward the second clean tank. 2. The machining fluid supply for a machine tool according to claim 1, wherein the backup filter is a rotatable disc-shaped filter, a part of which is exposed on the machining fluid surface, and is rotationally driven by a driving unit. apparatus. 3. The machining fluid supply device for a machine tool according to claim 1, wherein the jetting means ejects a clean machining fluid filtered by the filtration device.