JP2965820B2 - Machining method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a machining method for subjecting a workpiece to cutting or polishing.

[0002]

2. Description of the Related Art Conventionally, when a workpiece is subjected to cutting or polishing, in order to cool heat generated by collision between the workpiece and a processing tool, a water injection nozzle is extended toward a vicinity of a processing point. Liquid is being sprayed from the nozzle. For example, in a machining center (combined machine tool),
As shown in FIG. 3, a tool holder 2 is mounted on a lower end of a spindle (not shown in the drawing) in the main body 1, and a processing tool 4 is mounted on a tool connecting shaft 3 at the tip of the tool holder. A water injection nozzle 5 extends from the main body 1 toward the processing tool 4. However, when processing is performed by a vertical, large-sized machine tool such as this machining center, water and chips are likely to accumulate in the processing concave portion, and on the contrary, the processing performance may deteriorate. Also, in the case where cutting is performed by intermittently colliding a cemented carbide tool with the workpiece, the cutting edge becomes hot due to heat generation at the processing point, and is cooled by pouring at locations other than the processing point. There is a problem that chipping (so-called "chipping" phenomenon) or cracking occurs due to repeated rapid thermal changes.
In addition, in the method of applying liquid by using a water injection nozzle, the liquid scatters around, causing the worker's clothes to become dirty, causing the floor to slip due to the scattered liquid, and causing the collected liquid to contain cutting chips and the like. , Draining it out of the factory will lead to environmental pollution. For this reason, only the cutting chips are collected and recycled, but it is difficult to completely separate the water and the cutting chips, and there is a problem that it takes much time and effort.

[0003] In such a case, the machining waste is blown off only by the air flow without using the liquid, but the cooling effect and the lubricating effect on the workpiece and the tool are insufficient with the air flow alone. Therefore, for example, there is the following operational problem in cutting. That is,
In the cutting of carbon steel such as S45C, the surface of the workpiece is hardened by the cutting heat and becomes difficult to finish the surface such as polishing. The workpiece itself is heated and expands, and when it is cut in that state, the machining dimensions become inconsistent.The cutting heat melts the workpiece surface, and the molten metal adheres to the cutting edge of the cutting tool, resulting in a so-called `` constituent edge ''. There is a problem that the formed finished surface roughness and dimensional accuracy are deteriorated.

[0004] On the other hand, instead of applying the liquid as it is, spraying it in a mist state to impart lubricity to a workpiece and a working tool is also performed. According to this method, there is an advantage that water does not accumulate in the concave portion as in the case of liquid spraying, and there is an advantage that a certain degree of cooling effect can be obtained. There is a problem that the applicable range is limited.

[0005]

As described above, the conventional machining method can simultaneously satisfy the three problems of cooling a workpiece and a machining tool, removing machining chips, and imparting lubricity to a machining surface. It is not possible to do so, depending on the processing conditions, to select between liquid spraying, air flow, or mist-like spraying, and to simply perform processing while minimizing disadvantages during processing.

The present invention has been made in view of such circumstances, and can simultaneously satisfy the three problems of cooling a workpiece and a processing tool, removing processing chips, and imparting lubricity to a processing surface. Its purpose is to provide an excellent machining method.

[0007]

In order to achieve the above object, a machining method according to the present invention provides a method of processing a workpiece by spraying a liquid in a mist state toward a surface to be processed of the workpiece. A gas injection part of the atomized material injection nozzle is set so that ambient air is sucked in from one end and the flow rate is amplified and discharged from the other end in a state where the flow rate is amplified. The body is processed while supplying it to the surface to be processed with high thrust.

[0008]

That is, the inventor of the present invention has conducted a series of studies on a machining method which simultaneously satisfies the three subjects of cooling a workpiece and a machining tool, removing machining chips, and imparting lubricity to a machining surface. As a result, the nozzle for injecting the liquid in the form of a mist is a mist ejecting nozzle including a liquid ejecting unit and a gas ejecting unit, and the mist is ejected from the liquid ejecting unit, and the gas ejecting unit is configured to emit the mist. When the surrounding air is sucked in from the one end of the body jet nozzle and discharged from the other end while the flow rate is amplified, the atomized material jetted from the liquid jet unit is processed with high thrust. It turned out that it can be supplied to the surface. As a result, it has been found that an excellent cooling effect and an effect of removing the processing waste can be obtained, and that the effect of wetting the surface to be processed is also sufficient.

Next, the present invention will be described in detail based on embodiments.

[0010]

FIG. 1 shows an example of an apparatus in which the present invention is applied to machining by a machining center. The basic configuration of this machining center is the same as that of the conventional one.
Is held via a bearing, and a tapered fitting portion 2a of the tool holder 2 is detachably inserted and held in a tapered chuck portion 7 provided at the lower end thereof. A machining tool 4 is attached to a tool connecting shaft 3 below the tool holder 2.

An air supply pipe 10 extends from a lower end surface of the machining center main body 1, and a mist spray nozzle 11 described later is connected to the air supply pipe 10. Then, the discharge port 14 of the atomized body injection nozzle 11
Are fixed in a state facing the processing surface of the processing tool 4. A liquid supply pipe 12 for introducing a liquid to be atomized is connected to the atomized body injection nozzle 11.

As the mist injection nozzle 11, for example, one having a structure as shown in FIG. 2 is used. The mist spray nozzle 11 has a large tapered opening 20 at the end.
The liquid ejecting unit 12a is attached inward at the center of the opening 20. Further, when compressed air is supplied from the gas supply pipe 10 as shown by an arrow P, the air is discharged from an extremely narrow annular gap 21 inside and flows along the nozzle inner wall, and the air above the opening 20 is removed. Accompanying this flow, the air is sucked into the opening 20 (shown by a broken line R), and the air flow rate is greatly amplified. Then, the liquid is supplied from the liquid supply pipe 12 to the liquid ejecting section 12a, and the gas supply pipe 10
When compressed air is supplied from the mist, a mist (indicated by a dashed line S) is ejected from the liquid ejecting section 12a toward the ejection port 14. At this time, the mist is discharged with high thrust from the discharge port 14 by the amplified airflow. Moreover, the discharge flow further induces air around the discharge port 14 (indicated by a broken line T), so that it is further amplified.

Therefore, when a workpiece is processed by the machining center, when the air is supplied to the air supply pipe 10 and a predetermined liquid (water, oil, emulsion, etc.) is supplied to the liquid supply pipe 12, the mist is formed. The atomized material ejected from the liquid ejecting portion 12a of the body ejecting nozzle 11 is ejected in a state of being mixed with the compressed air, and the surrounding air is drawn into the nozzle from the opening 20. The liquid is discharged from the discharge port 14 while being amplified to a large flow rate. The flow of the discharged mist is
Since the thrust is strong and strongly strikes the work surface of the workpiece and the work surface of the working tool 4 pressed against the work surface, chips and the like generated at the time of working are different from the conventional case where a mist is simply applied. It has the power to blow away enough. For this reason, chips and the like do not accumulate in the vicinity of the processing portion, and the cooling effect is high in combination with the above-mentioned amplified large flow of air. In addition, the discharged mist appropriately moistens the workpiece and the processing tool 4 and enhances lubricity, so that the processing performance is improved. Therefore, there is an advantage that the load on the working tool 4 is reduced, and there is no intermittent thermal shock because the cooling is not abruptly performed as in the case of liquid pouring. In addition, unlike the related art, it is possible to prevent the water injection liquid from splashing and contaminating the clothes of the worker and the splashed liquid from causing the floor contamination such as slippage of the floor. And
Since the type of liquid to be ejected by the atomized material can be changed according to the processing conditions, for example, in the case of high-speed cutting, the cooling effect is increased by using water as the liquid, By using oil, the lubricating effect can be enhanced.

Further, by providing a dust collector (dust suction device) in the vicinity of the processing surface by making use of the characteristics of the atomized material, it is possible to compare the separation and collection of cutting chips and liquid, which was difficult with the conventional liquid spray type. Can be easily performed. That is, when the atomized body is water, the moisture is fine particles, so that the water is evaporated immediately by the heat of the cutting surface and does not mix with the cutting chips. Therefore, only the cutting waste can be sucked and collected by the dust collector. When the mist is oil, a mist catcher is attached to the dust collector, and the floating oil particles can be collected by agglomerating into large oil droplets with the mist catcher.

In the above embodiment, it is preferable that the average particle diameter of the mist sprayed from the mist spray nozzle 11 is usually set to about 5 to 200 μm, though it depends on the processing conditions. is there. And the injection amount of the mist is
Normally, one to one continuously per atomized spray nozzle
It is preferably set to about 00 cc / min, and particularly preferably to 80 cc / min or less. That is, if the spray amount of the atomized material is set too large, the supply of the atomized material becomes excessive, and as in the case of the liquid spray type, the processing performance is reduced due to the accumulation of liquid in the processing concave portion, and causes a chipping phenomenon. In addition, there is a possibility that the surrounding mist is caused by the excess mist.

Further, in the above embodiment, the amount of gas flow amplification by the mist injection nozzle 11 is determined by the amount of the liquid injection unit 1.
Although it is appropriately set according to the injection amount of the atomized material injected from 2a and the processing conditions, it is usually preferable to set the amount to about 10 to 50 times the amount of air supplied from the air supply pipe 10. . In particular, setting the thrust of the atomized material discharged from the discharge port 14 to be 0.13 g / cm ² or more at a position 200 mm away from the end face of the discharge port 14 is effective in cooling and processing. It is suitable from the viewpoint of removing dust.

In the above-described embodiment, the mist injection nozzle 11 is used to introduce only one kind of liquid and atomize it. However, two kinds of liquids are separately introduced, and A liquid ejecting unit that can eject a mist from a nozzle may be used. Alternatively, two or more types of liquids may be introduced into the liquid supply pipe 12 in a mixed state. When these nozzles are used, it is possible to form a mist in which, for example, water particles and oil particles (or three or more types of particles) are mixed. Can be supplied. Then, when it is desired to enhance the cooling effect, the supply amounts of water and oil are adjusted so that the mixing ratio of water in the mist is increased, and when the lubricating effect is increased, the mixing ratio of oil is increased. By making adjustments, it is possible to easily create an optimum environment for the processing.

Further, the present invention is not limited to machining by a machining center as in the above embodiment,
The present invention can be applied to machining using various machine tools such as a grinder.

[0019]

As described above, according to the machining method of the present invention, the mist is ejected from the liquid ejecting section in the mist ejecting nozzle, and the gas ejecting section is provided at one end of the mist ejecting nozzle. And the surrounding air is sucked in from the other side and discharged from the other end in a state where the flow rate is amplified, thereby supplying the atomized material ejected from the liquid ejecting unit to the surface of the workpiece with high thrust. It is designed to perform machining while doing so.
Therefore, since the mist is strongly applied to the workpiece processing surface and the processing tool pressed against the workpiece, unlike the case where the mist is simply applied as in the related art, chips generated at the time of machining can be sufficiently removed. Has the power to blow away. For this reason, chips and the like do not accumulate in the vicinity of the processing portion, and the cooling effect is high in combination with the above-mentioned amplified large flow of air. In addition, the discharged mist appropriately moistens the workpiece and the processing tool, and enhances the lubricity, so that the processing performance is improved. Therefore, the load on the machining tool is reduced, and it does not receive sudden cooling like liquid pouring.
It has the advantage that there is no intermittent thermal shock and tool life is greatly extended. And, since the type of liquid to be ejected by the atomized material can be changed according to the processing conditions, for example, in the case of high-speed cutting, the cooling effect is enhanced by using water as the liquid, and in the case of medium / low-speed cutting, Can be used properly, for example, by using oil as a liquid to enhance the lubricating effect. Further, if two or more kinds of liquids such as water and oil are simultaneously sprayed to form a mixed mist and supplied near the processing point with high thrust, a more effective processing environment can be created. In this case, by adjusting the supply amounts of the respective liquids to be supplied to the atomized material injection nozzle, it is possible to easily create an optimum processing environment according to the target processing. Moreover, the use of the atomized material has the advantage that the working environment can be kept clean and the processing waste can be easily collected and reused.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of an apparatus used in the present invention.

FIG. 2 is an explanatory view of a mist injection nozzle used in the embodiment.

FIG. 3 is an explanatory view of a water injection method in conventional machining.

[Explanation of symbols]

 11 mist spray nozzle

Claims (3)

(57) [Claims] When a workpiece is machined, a mist spray nozzle for spraying a liquid in a mist toward a surface to be processed of the workpiece is provided. A process in which the air is set to be discharged from the other end in a state where the air is entrained and the flow rate is amplified from one end, and the mist is supplied to the surface to be processed with high thrust. Processing method. 2. Discharge from the other end side of the mist injection nozzle
The thrust of the atomized spray is the discharge end face of the spray nozzle.
0.13g / cm at a position 200mm away from ^TwoOver
The machining method according to claim 1, wherein the setting is made such that: 3. The machining method according to claim 1, wherein the spray amount of the mist is continuously set to 80 cc / min or less per one mist spray nozzle.