JP4920139B2 - Mist generator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a mist generating device that generates oil mist to be supplied to a processing point of a machine tool, for example.
[0002]
[Prior art]
The present applicant has proposed such a mist generating apparatus in Japanese Patent Laid-Open No. 2000-65291. This apparatus is provided with a tank for containing oil in the lower part and a mist in the upper part, and a nozzle for generating mist by mixing air and oil is provided on the top wall of the tank. The nozzle has a vertical passage that communicates with the tank in a vertical direction and a horizontal passage that communicates horizontally with the vertical passage. Air is pumped from a pressure air source to the vertical passage of the nozzle, and oil is pumped to the horizontal passage of the nozzle by a pump.
[0003]
The pump is composed of a plunger for pressurizing oil, an operation part for operating the plunger automatically or pneumatically, a relay contact for switching on / off operation of the plunger, a check valve for circulating oil only in one direction, etc. It is made up. The pump repeats the on / off operation of the plunger, and adjusts the amount of oil discharged from the nozzle according to the frequency.
[0004]
[Problems to be solved by the invention]
However, since the mist generating device described above adjusts the oil discharge amount according to the frequency of the plunger on / off operation, the frequency of the plunger on / off operation increases when the oil discharge amount is increased, and the plunger slides. In addition to wear of the moving parts, the life of the relay contacts is also shortened.
[0005]
An object of the present invention is to provide a mist generating apparatus that solves the above-mentioned problems and improves the reliability and life without using a pump.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a mist generating apparatus according to the present invention includes a nozzle that mixes air and oil to generate oil mist, and the nozzle is configured to generate the oil mist by the negative pressure of the air that has flowed in through a tubular body. In the mist generating apparatus for sucking up air, a plurality of branch pipes are provided in the middle of the pipe to branch the air flow into a plurality of passages and then merge into one passage, and each of the branch pipes opens and closes the pipe. An on- off valve that performs the above and a flow rate adjustment valve that adjusts the air flow rate of the pipe line are arranged in series, and the flow rate of air flowing into the nozzle is controlled by a combination of the branch circuit, the on-off valve, and the flow rate adjustment valve . wherein adjusting the discharge amount of the oil from the nozzle, the particle size of the oil mist generated screened in the mist chamber, characterized Rukoto drained only small particles.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in detail based on the illustrated embodiment.
FIG. 1 is a configuration diagram including a pneumatic circuit of a mist generating apparatus according to an embodiment. The mist generating apparatus according to this embodiment includes a tank 1 that can contain oil O. A nozzle 2 that mixes air and oil O to generate oil mist is provided on the top wall 1 a of the tank 1. The nozzle 2 has a vertical passage 2a which faces the vertical direction 2 and communicates with the tank 1 from the outside, and a horizontal passage 2b which faces the horizontal direction and communicates with the vertical passage 2a from the outside. That is, the nozzle 2 is of a so-called self-priming type in which the oil O is sucked up by the negative pressure generated by the air flowing through the vertical passage 2a.
[0008]
Pressure air from the pressure air source 3 is introduced into the nozzle 2 through the pipe bodies 4a to 4f, the filter 5, the pressure reducing valve 6, the pressure gauge 7, the separator 8, the electromagnetic valve 9, and the flow rate adjusting means 10 indicated by a one-dot chain line. Has been. And the pressurized air from the electromagnetic valve 9 is introduce | transduced into the tank 1 via the pipe bodies 11a-11c, the pressure-reduction valve 12, and the pressure gauge 13, and the inside of the tank 1 is pressurized.
[0009]
As shown in the partially enlarged view of FIG. 2, the inside of the tank 1 is partitioned up and down by a partition plate 21 having an oil passage 21 a, and the interior of the tank 1 above the partition plate 21 is a cylindrical body 22. It is divided into the inside and outside by. Below the partition plate 21 is an oil storage chamber 23, the inside of the cylindrical body 22 is an internal mist chamber 24, and the outside of the cylindrical body 22 is an external mist chamber 25. The upper end of the cylindrical body 22 is integrated with the top wall 1a of the tank 1, and the lower end of the cylindrical body 22 is substantially closed by an end wall 22b having an oil through hole 22a. A tubular body 26 is spirally wound around the outer peripheral surface of the tubular body 22, the upper opening of the tubular body 26 is communicated with the upper portion of the internal mist chamber 24, and the lower opening of the tubular body 26 is the lower portion of the external mist chamber 25. It is communicated to.
[0010]
A pipe body 4 f from the flow rate adjusting means 10 is connected to the vertical passage 2 a of the nozzle 2, and a pipe body 27 for introducing the oil O accommodated in the lower part of the tank 1 is connected to the horizontal passage 2 b through a filter 28. It is connected. The mist in the external mist chamber 25 can be supplied to a machining point of a machine tool (not shown) via the tube 29, and the tube 29 is provided with a pressure gauge 30. In addition, the above-described tube body 11c is connected to the external mist chamber 25, and the mist in the external mist chamber 25 can be pumped to the machining point of the machine tool through the tube body 29.
[0011]
Here, the flow rate adjusting means 10 includes, for example, three pipe bodies 31 to 33 branched from the pipe body 4e, three electromagnetic valves 34 to 36 respectively connected to the pipe bodies 31 to 33, and these Flow regulating valves 40 to 42 respectively connected to the solenoid valves 34 to 36 through the pipes 37 to 39, and pipes 43 to 45 for connecting the flow regulating valves 40 to 42 and the pipe 4f described above. It is composed of
[0012]
The solenoid valves 34 to 36 are open / close valves, and at least one of the three solenoid valves 34 to 36 is opened to adjust the air flow rate. Moreover, the opening degree of the flow rate adjusting valves 40 to 42 can be controlled, for example, 0 rotation, 2 rotations, 4 rotations, 6 rotations, and fully open, and the air flow rate is adjusted in multiple stages by various combinations of the respective opening degrees . It has come to be able to do. The electromagnetic valves 34 to 36 and the flow rate adjusting valves 40 to 42 can be manually operated by a manual switch and automatically operated by a signal from a machine tool, for example.
[0013]
In this mist generating device, the pressure air from the pressure air source 3 flows into the flow rate adjusting means 10 through the filter 5, the pressure reducing valve 6, the pressure gauge 7, the separator 8, and the electromagnetic valve 9. In the flow rate adjusting means 10, the pressure air from the electromagnetic valve 9 is branched into three and flows through the electromagnetic valves 34 to 36 and the flow rate adjusting valves 40 to 42, and then merges and flows into the vertical passage 2 a of the nozzle 2.
[0014]
Then, when air flows through the vertical passage 2 a of the nozzle 2, a negative pressure is generated in the horizontal passage 2 b, and this negative pressure sucks up the oil O in the tank 1 through the filter 28 and the pipe body 27. As a result, air and oil O are mixed inside the nozzle 2 and discharged from the lower end of the nozzle 2 to the internal mist chamber 24 as primary mist. During this time, the solenoid valves 34 to 36 and the flow rate adjusting valves 40 to 42 are operated in multiple stages to control the flow rate of the air flowing into the nozzle 2 and adjust the discharge amount of the oil O at the nozzle 2.
[0015]
For example, FIG. 3 shows the discharge amount mL / h of the oil O when the opening degree of any one of the flow rate adjusting valves 40 to 42 is 0, 2, 4, 6 and fully opened. FIG. However, the diameter of the lower end of the vertical passage 2a of the nozzle 2 is 1.6 mm or the area thereof is 2 mm ² , the supply pressure of the pressurized air, that is, the pressure indicated by the pressure gauge 7 is 0.5 MPa, and the discharge pressure of the mist at the nozzle 2 is 0.4 MPa. As can be seen from this graph, the discharge amount of the oil O increases in proportion to the opening degree of the flow rate adjusting valves 40 to 42. Therefore, the discharge amount of the oil O in the nozzle 2 can be adjusted by controlling the electromagnetic valves 34 to 36 and the flow rate adjusting valves 40 to 42.
[0016]
In this way, the primary mist discharged from the nozzle 2 fills the internal mist chamber 24. During this time, large particles in the primary mist adhere to the inner surface of the cylindrical body 22, and the liquefied oil O falls into the oil storage chamber 23 through the oil through holes 22 a and 21 a, and enters the internal mist chamber 24. A secondary mist consisting only of small particles remains.
[0017]
Next, the secondary mist in the internal mist chamber 24 flows out to the external mist chamber 25 through the tube body 26. During this time, large particles in the secondary mist pass through the helical tube body 26 and receive centrifugal force to adhere to the inner surface, and tertiary mist consisting only of small particles flows out to the lower part of the external mist chamber 25. Further, the liquefied oil O travels along the inner surface of the pipe body 26 and falls from the pipe body 26 and falls into the oil storage chamber 23 through the oil through hole 21a.
[0018]
Then, the tertiary mist flowing into the lower portion of the external mist chamber 25 rises, and during this time, large particles in the tertiary mist adhere to the inner surface of the tank 1, and the liquefied oil O passes through the oil passage hole 21a and the oil storage chamber. It falls to 23. As a result, a quaternary mist consisting only of small particles remains in the upper part of the external mist chamber 25, and the quaternary mist flows out through the tube 29 to the machining point of the machine tool.
[0019]
In this embodiment, it becomes possible to control the flow rate of air in multiple stages by the electromagnetic valves 34 to 36 and the flow rate adjusting valves 40 to 42, and the flow rate of air flowing into the nozzle 2, that is, the discharge of oil O from the nozzle 2. The amount can be adjusted. Therefore, the conventional pump becomes unnecessary, there is no worn part, and the reliability and life are improved.
[0020]
In the above-described embodiment, the flow rate adjusting means 10 is configured by the three electromagnetic valves 34 to 36 and the three flow rate adjusting valves 40 to 42, but it is not necessary to have three. Further, instead of the solenoid valves 34 to 36, other types of pneumatic pilot valves or the like are used, and instead of the flow rate adjusting valves 40 to 42, a voltage or current proportional control valve that can adjust the air flow rate steplessly is used. There is no hindrance. And although the filter 5, the pressure reducing valve 6, the pressure gauge 7, and the separator 8 were arrange | positioned between the pressure air source 3 and the solenoid valve 9, these can be made into an option.
[0021]
【Effect of the invention】
As described above, in the mist generating apparatus according to the present invention, a plurality of branch pipes that divide an air flow into a plurality of passages and then merge into one passage are arranged in the middle of the pipe body, and the plurality of branch pipes Since the on-off valve and the flow rate adjusting valve are provided on the path , the flow rate of the air flowing into the nozzle, that is, the amount of oil mist discharged from the nozzle can be adjusted in multiple stages by controlling the on-off valve and the flow rate adjusting valve. . Therefore, the conventional pump for pumping oil to the nozzle is not required, and the worn part can be eliminated to improve the reliability and life.
[Brief description of the drawings]
FIG. 1 is a configuration diagram including a pneumatic circuit according to an embodiment. FIG. 2 is a partially enlarged view.
FIG. 3 is a graph of the opening of the flow rate adjustment valve and the oil discharge amount.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Tank 2 Nozzle 3 Pressure air source 6, 12 Pressure reducing valve 10 Flow rate adjustment means 34-36 Electromagnetic valve 40-42 Flow rate adjustment valve O Oil

Claims (2)

A nozzle that mixes air and oil to generate an oil mist, and the nozzle sucks the oil by a negative pressure of the air that has flowed in through a tubular body; A plurality of branch pipes that diverge the flow into a plurality of passages and then merge into one passage are provided, and each of these branch pipes is an on- off valve that opens and closes the pipe and a flow rate adjustment valve that adjusts the air flow rate of the pipe Are arranged in series, and the amount of oil discharged from the nozzle is adjusted by controlling the flow rate of air flowing into the nozzle by a combination of the branch circuit, the on-off valve, and the flow rate control valve , and is generated. the particle size of the oil mist screened in mist chamber, mist generating device according to claim Rukoto drained only small particles.   The mist generating apparatus according to claim 1, wherein the on-off valve is an electromagnetic valve.

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