JPH10235507A - Drilling method and drilling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply sufficient water-soluble cutting fluid for the lubrication and cooling during drilling work by a drilling tool such as a drill, a tap, etc. SOLUTION: In a drill 150, oil holes 158 passing through it from the base end side to the tip side, are formed. A mist of water soluble cutting fluid generated by a mist generating device is supplied in the oil holes 158 from the base end side of the drill 150. During drilling work by the drill 150, sufficient water soluble cutting fluid for the lubrication and cooling is supplied in the hole during drilling by jetting the water soluble cutting fluid from the tip of the drill 150.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drilling method and a drilling device for lubrication and cooling during cutting of metal or the like.

[0002]

2. Description of the Related Art In cutting a metal or the like, it is necessary to perform lubrication and cooling in a region to be processed in order to improve machining efficiency and extend the life of a tool.

[0003] For this reason, conventionally, oily or water-soluble cutting fluid is coated in a liquid state through a nozzle provided near a drilling tool such as a drill or a tap or an oil hole formed inside the drilling tool itself. A method of supplying the material to the processing area is generally used.

However, in such a method of supplying the cutting fluid in a liquid state to the region to be processed, a large amount of the cutting fluid is consumed, so that the machining cost is increased and resources are wasted. In addition, the cutting fluid scattered to the surroundings causes troubles of the processing apparatus, deterioration of the working environment, and the like. In particular, under the current situation where ISO 14000 has been standardized against the background of increasing global environmental awareness, it is necessary to avoid such a situation.

Therefore, for example, as shown in FIG.
A method of spraying the mist of the oil-based cutting fluid generated according to the above method onto the processing area of the workpiece A has been separately proposed.

That is, in this method, as shown in FIG. 15, an oil-based cutting fluid 302 is continuously dropped into a nozzle 300 to which air of about 10 kgf / cm ² is supplied.
The oil-based cutting fluid 302 is mixed with air in the nozzle 300 and is ejected in a mist form from a tapered nozzle tip 300a.

[0007]

However, according to the above-mentioned method, the generated mist is sprayed.
Since it is the surface of the workpiece A, there is a problem that a sufficient oil-based cutting fluid required for lubrication and cooling does not flow into the hole being processed.

Accordingly, the present invention has been made to solve the above-described problem, and it is possible to sufficiently supply a cutting fluid necessary for lubrication and cooling during drilling with a drilling tool such as a drill or a tap. It is an object of the present invention to provide a drilling method and a drilling device that can be performed.

[0009]

In order to solve the above problems, a drilling method according to the present invention is a drilling method for processing a workpiece by a drilling tool,
An oil hole penetrating from the base end to the tip end of the drilling tool is formed, and a mist of a water-soluble cutting fluid is supplied into the oil hole from the base end of the drilling tool to form a tip of the drilling tool. Drilling the workpiece while ejecting the mist from the part.

In addition, the drilling apparatus of the present invention rotatably supports a drilling tool having an oil hole penetrating from the base end to the distal end, and has a mist inlet and a mist inlet. A drilling device main body in which a flow path for guiding the supplied mist of the water-soluble cutting fluid from the base end side of the drilling tool to the oil hole is formed, and the generated mist is supplied to the mist introduction port. A mist generating device for jetting from the tip of the drilling tool through the flow path and the oil hole.

Further, the mist generating device has an oil flow passage formed therein for discharging a water-soluble cutting fluid supplied from a base end side to a front end side, and an outer peripheral surface at a front end side has an oil passage section. It has an inner cylinder part finished to a tapered peripheral surface whose outer diameter dimension is sequentially reduced in diameter toward the distal end, and an outer jacket is provided so as to cover the tapered peripheral surface, and the tapered peripheral surface and An air channel portion is formed along the tapered peripheral surface between the outer cylindrical portion and the inner peripheral surface, and the air supplied from the base end side of the air channel portion is supplied along the air channel portion to the inner cylindrical portion. It is preferable to use one that sends the water-soluble cutting fluid to the oil flow path portion in a pulsed manner and generates a mist while sending it to the front end side.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A drilling method and a drilling apparatus according to an embodiment of the present invention will be described below.

That is, as shown in FIG. 1, the drilling apparatus is configured such that a mist pipe 6 extending from a mist supply device 2 for generating and supplying a mist of a water-soluble cutting fluid is attached to a workpiece A. On the other hand, it is connected to a drilling machine 100 as a drilling apparatus main body for drilling and the like.

As shown in FIGS. 2 and 3, the mist supply device 2 sucks up a water-soluble cutting fluid stored in a tank 4 by a pump 10 and supplies it to a mist generation device 50, and also supplies it from outside. The air having a predetermined pressure is supplied to the mist generating device 5 through the regulating valve 20 and the pressure regulating unit 30.
It is configured to supply 0.

A suction pipe 12 provided with a filter 14 at an open end extends downward from the pump 10 to the tank 4. The water-soluble cutting fluid in the tank 4 sucked up through the suction pipe 12 is The oil is supplied from the rear end side of the mist generating device 50 via the oil pipe 16.

The pump 10 is configured to supply the sucked-up water-soluble cutting fluid to the mist generating device 50 in a pulsed manner, and the number of pulses per minute and the stroke amount per one pulse. The amount is adjustable by a stroke adjustment dial 42 and a pulse number adjustment dial 44 provided on a panel 40 on the front of the mist supply device 2.

Air such as factory air supplied into the apparatus 2 via the air pipe 18a is first sent into the adjustment valve section 20. The pump 1 includes
A solenoid valve electrically connected to the pump 10 is used.
Thus, the solenoid valve is kept open only while the water-soluble cutting fluid is supplied in a pulsed manner so that air is supplied.

Air is supplied from the regulating valve section 20 to the air pipe 1.
8b, the pressure of the air is supplied to the pressure adjusting unit 30, and the measured air pressure is displayed by a pressure gauge 46 provided on the panel 40, and the pressure of the air is adjusted by the pressure adjusting dial 48 of the panel 40. Air piping 18
The mist is supplied to the mist generating device 50 through the line c.

When the water-soluble cutting fluid and the air are supplied to the mist generating device 50, the water-soluble cutting fluid is generated in a mist state (an example of the mist generating device 50 will be described later) and generated. The mist is supplied to the drilling machine 100 via the mist pipe 6.

The drilling machine 100 is provided with a table 104 on which a workpiece A is mounted and fixed on a base 102, and a column 106 standing on the back side of the base 102. 108 is configured to be vertically movable. As shown in FIGS. 1 and 4, the head 108 has a rotary drive unit 11 such as a motor.
0 is provided, and a drill 150 as a drilling tool is supported in a hanging manner via a cylindrical holder 120 fixed to the rotation driving means 110.

As shown in FIGS. 5 and 6, the drill 150 has a body 154 having a prismatic shank 152 at its base end and a spiral edge 156 at its tip end. Have. And the drill 150
A pair of oil holes 158 penetrating along the edge 156 from the base end side to the front end side is formed inside, and the base end side of these oil holes 158 is opened to the base end side surface of the shank 152, and the front end side is the body 154. Is open at the flank 155 at the tip of the.

On the other hand, the holder 120 is formed with a hollow hole 122 that opens downward from the inside thereof, and the inner peripheral surface of the holding hole 122a below the hollow hole 122 has a drill 15 shape.
It is formed in a square hole shape corresponding to the shape of the 0 shank 152. When the screw 124 provided on one side of the hole wall of the holding hole 122a is tightened in a state where the shank 152 is inserted through the holding hole 122a, the drill 150 is fixed to the holder 120 in a non-rotating state. In addition, the hollow hole 12
A plurality of communication holes 126 are formed in the hole wall of the upper hollow portion 122b along the circumferential direction thereof, and a space D surrounded by the upper end surface of the shank 152 and the inner peripheral surface of the hollow portion 122b is formed by each communication hole portion. It is configured to communicate with the outside of the holder 120 via 126.

An oil seal 130 is externally mounted on the upper part of the holder 120. A circumferential groove 13 is provided at a position surrounding each communication hole 126 of the oil seal portion 130.
2 are formed, thereby forming a donut-shaped space E surrounding each communication hole 126 in the circumferential direction. A bearing 134 and an oil seal 136 are interposed at contact positions between the upper and lower oil seal portions 130 and the holder 120 of the space E, respectively. Also, the oil seal portion 130
Is fixed to the head 108 via a support pillar 140 extending from one side of the base end side. Thus, the space E
Is sealed from the outside, and the holder 120 is rotatable with respect to the oil seal portion 130 fixed in a non-rotating state.

The oil seal 130 has a space E
A flow path F is formed from one side to a position where the support pillar 140 extends, and a flow path G is formed inside the support pillar 140. Further, the support pillar 140
A mist inlet 142 for connecting the mist pipe 6 is provided on the head 108 side.

That is, the mist supplied to the mist inlet 142 through the mist pipe 6 is transferred to the flow path G of the support column 140, the flow path F of the oil seal 130, and the donut-shaped space (flow path) E. Flow in. Here, the mist that has flowed into the sealed space E is the holder 1 that is being driven to rotate.
20 flows into the space D through the 20 communication holes 126. The mist that has flowed into the space (flow path) D flows into the oil hole 158 from the opening of the oil hole 158 at the upper end surface of the shank 152, and
0 It will be ejected from the tip.

The outline of the operation at the time of drilling by the above-described drilling apparatus will be described below.

That is, the drill 1 is driven by the rotation driving means 110.
By lowering the head 108 while rotating the 50,
Drilling of the workpiece A is performed. At this time, the mist of the water-soluble cutting fluid generated by the mist supply device 2 is
The mist is sprayed from the oil hole 158 at the tip of the drill 150 in advance. That is, while the mist is ejected from the tip of the drill 150, the tip of the drill 150 is pressed against the workpiece A to perform the drilling. Then, for example, as shown in FIG. 7, in a state where the drilling process has progressed to some extent and the drill 150 has sunk into the workpiece A to a certain extent, the mist ejected from the tip of the drill 150 is at the bottom of the processed hole 180 After being sprayed on 180a, spiral grooves and holes 180 between each edge 156
It is discharged to the outside of the hole 180 through the gap between the inner peripheral surface.

According to the drilling method and drilling apparatus configured as described above, the mist of the generated water-soluble cutting fluid is jetted from the tip of the drill 150 through the oil hole 158 formed in the drill 150. Therefore, the mist is sprayed on the bottom 180a of the hole 180 during the processing in which the mist was difficult to pass in the past, and sufficient lubrication and cooling properties are provided between the cutting edge at the tip of the drill 150 and the bottom 180a. can get. Also, as shown in FIG.
Since the mist sprayed on Oa is easily vaporized there, the mist is excellent in cooling performance as compared with the case where the conventional water-soluble cutting fluid is supplied in a liquid state into the hole. Further, heat generated by friction between the tip portion of the drill 150 and the bottom portion 180a and shavings generated by the drilling process pass between the spiral groove of the drill 150 and the inner peripheral surface of the hole 180 by spraying mist. As a result, the material is discharged out of the hole 180 so that sufficient cooling for processing can be achieved, and the removal of shavings from the hole 180 is also effectively performed.

For example, when a conventional water-soluble cutting fluid is liquefied and spouted from the tip of the drill through the oil hole of the drill while drilling, a cutting distance of about 11 m is obtained at a cutting speed of 100 m / min. However, in the drilling method according to the present invention, a higher cutting speed of 120 m / min, 150
It was found that even under the condition of m / min, the cutting distance until the tool life expired was about 15.4 m or more, and that the tool life was extended even at a higher machining speed.

Since the water-soluble cutting fluid is sprayed into the processing area in the form of a mist, the water-soluble cutting fluid is supplied to the processing area in a liquid state as compared with the conventional water-soluble cutting liquid. The consumption can be dramatically reduced, and ISO 14000
Certification can be obtained, contributing to environmental conservation.

In addition, this drilling apparatus can use a conventional drilling machine that supplies a water-soluble cutting fluid in a liquid state to an area to be processed through an oil hole.
Existing equipment can be used as is.

The oil hole 1 of the drill 150
The structure for supplying mist to 58 is not limited to the above structure, and may be any structure that can supply mist to oil hole 158 of rotating drill 150.

When the drilling machine 100 is a multi-axial drilling machine and is provided with a plurality of drills 150, the mist pipe 6 extended from the mist supply device 2 is branched into a plurality of pieces. Oil hole 1 for each drill 150
58.

Further, the mist supply device 2 and the drilling machine 10
It is not necessary to provide the mist generating device 50 directly on the drilling machine 100, and supply air and a water-soluble cutting fluid to the mist generating device to generate a mist. You may make it supply to the hole 158.

In the above embodiment, the case where the drill 150 is used has been described. However, other drilling tools, such as taps and reamers, which perform drilling, similarly have the tip of the tool being processed. If the mist of the water-soluble cutting fluid is ejected from the portion, the same effect as above can be obtained. For example, when the drilling tool is a tap, as shown in FIG. 8, the shank 196 is inserted from the tip side of each groove 194 between the screw portions 192 formed in the longitudinal direction of the tap 190.
An oil hole 198 that penetrates the base end surface may be formed.

When the conventional mist generation method as shown in FIG. 15 is applied to the mist generation device 50 in the above embodiment, the generated mist is drilled through the mist pipe 6 and the flow paths G, F and the like. It cannot be supplied into the 150 oil holes 158. This is because the particles of the water-soluble cutting fluid of the mist generated by the method shown in FIG. 15 are very coarse, and the particles collide with each other and join together in the middle of the mist pipe 6 or the like, and the state of the mist is changed. This is because it cannot be maintained.

Therefore, a mist generating apparatus suitable for implementing the above embodiment will be described below.

As shown in FIGS. 9 to 11, the mist generating device 50 has an oil flow path portion 60 for discharging a water-soluble cutting fluid supplied from the base end side to the front end side. In addition, the outer peripheral surface on the distal end side has an inner cylindrical portion 52 formed on a tapered peripheral surface 54 whose outer diameter dimension gradually decreases in the distal direction, and the inner cylindrical portion 52 has a substantially cylindrical outer jacket. The air passage portion 85 is formed along the tapered peripheral surface 54 between the tapered peripheral surface 54 and the inner peripheral surface of the outer cover portion 80 by externally fitting the portion 80.

As shown in FIG. 10, a small diameter portion 62, a middle diameter portion 64, and a large diameter portion 66 are formed in the oil passage portion 60 of the inner cylinder portion 52 in this order from the front end side. An oil pipe (not shown in FIGS. 9 to 11) for connecting a water-soluble cutting fluid from the outside to the base end is formed so as to gradually increase in diameter toward the end. Are provided.

The reason why the inner diameter of the oil flow passage portion 60 is increased stepwise toward the base end side as described above is that the oil flow passage portion 60 needs to be formed at the front end side as a condition of mist generation as described later. This is to ensure a small diameter and to secure an appropriate internal capacity (described later) of the oil flow path portion 60 with respect to the supply amount of the water-soluble cutting fluid.

The outer diameter of the distal end surface of the inner cylindrical portion 52 is three times the inner diameter of the small diameter portion 62, that is, the thickness of the inner cylindrical portion 52 is the same as the inner diameter of the small diameter portion 62. It has been.

From here, a tapered peripheral surface 54 whose outer diameter dimension gradually increases toward the base end side is formed in a region corresponding to the small diameter portion 62 and the medium diameter portion 64 on the outer peripheral surface of the inner cylindrical portion 52. I have. In addition, the trunk portion 56 is formed in a region corresponding to the large-diameter portion 66 on the proximal end side from the maximum outer diameter portion on the proximal end side of the tapered peripheral surface 54, and the connecting portion 68 on the proximal end side of the trunk portion 56. A peripheral projection 58 is formed in a region corresponding to the above-mentioned shape so as to be fitted in close contact with an outer cover 80 described later.

On the other hand, as shown in FIG. 9 and FIG. 11, the outer jacket 80 includes a jet chamber 82, a tapered housing 84, a housing body 86, and a housing projection 88 in this order from the tip side.

The ejection chamber 82 is disposed in a region on the distal end side of the inner cylinder 52, and mist is generated in the inner region.
A connecting portion 81 for connecting a mist pipe for supplying the generated mist to an external tool is provided on the distal end side.

The tapered housing portion 84 is disposed in a region corresponding to the tapered peripheral surface 54, and covers the tapered peripheral surface 54 at a position separated from the peripheral surface 54 by a predetermined distance. An air flow path portion 85 having a predetermined width is formed between the tapered housing portion 84 and the inner peripheral surface.

A housing body 86 is arranged in a region corresponding to the body 56 from the maximum outer diameter portion on the base end side of the tapered peripheral surface 84. The housing body 86 covers the body 56 at a position separated by a predetermined distance from the peripheral surface, and the outer circumferential surface of the body 56 and the housing body 8.
6, an air introducing space 87 having a predetermined width is formed between the inner peripheral surface and the inner peripheral surface, and an air supply pipe (not shown) is provided above the air introducing space 87.
Are connected to each other.

The peripheral projection 58 on the base end side of the housing body 86
A housing projection 88 is provided in a region corresponding to the above. ing.

Hereinafter, a method of generating mist by the mist generating device 50 and its principle will be schematically described.

First, the connecting portion 90 on the base end side of the air flow path portion 85
While introducing air of a predetermined pressure from the, the water-soluble cutting fluid intermittently from the connecting portion 68 on the base end side of the oil flow path portion 60,
That is, it is supplied in a pulse form.

Then, as shown in FIG. 12, while the supply of the water-soluble cutting fluid is stopped, the air flowing along the air flow path 85 causes the air flow on the tip side of the inner cylinder 52 to flow. A high-speed air flow path G is formed on the extension of 85.

A substantially conical space V surrounded by a conical peripheral surface extending toward the distal end from the tapered peripheral surface 54 is formed inside the flow path G, and flows through the flow path G. The high-speed air flows toward the tip while entraining the gas in the space V.

When the gas is entrained from the space V into the flow path G by the high-speed air, a vortex having a high rotational speed is formed in the space V as shown in FIG.
Since the supply of the water-soluble cutting fluid is stopped from the oil flow path portion 60 on the base end side of the space V, the state becomes a low pressure state extremely close to a vacuum state.

At this time, in the space V, the degree of vacuum increases along the conical surface. When such a high degree of vacuum is formed in the oil flow path 60,
As will be described later, since the water-soluble cutting fluid is less likely to be sucked from the oil passage portion 60, in order to avoid this, the thickness of the pipe wall at the tip of the inner cylindrical portion 52 is set equal to the inner diameter of the small-diameter portion 62 in order to avoid this. It is set to about.

In this state, when the water-soluble cutting fluid is supplied to the oil flow path portion 60, the water-soluble cutting fluid in the flow path portion 60 is sucked out by the negative pressure of the swirling space V, and the leading end side thereof is discharged. Is ejected into the ejection chamber portion 82 of the nozzle.

When the supply of the water-soluble cutting fluid is stopped again, a low-pressure space V is formed again at the tip end of the opening of the oil flow path 60, and the above operation is repeated.

The mist generating device 5 configured as described above
According to No. 0, the water-soluble cutting fluid is sucked from the inside of the oil flow channel portion 60 by the low-pressure space V in which a fast-flowing vortex is swirled, and is ejected into the ejection chamber portion 82. A mist composed of liquid particles can be generated.

Even if the mist thus generated passes through the pipe, the particles hardly collide with each other and combine, and the generated mist passes through the mist pipe to a position far away from the mist generator. It becomes possible to supply. Therefore, it is suitable for implementing the method of spraying mist through an oil hole such as a drill as in the above embodiment.

Further, when the mist composed of very fine particles of the water-soluble cutting fluid is sprayed on the region to be processed, the adhesion to the workpiece is smaller than when the mist composed of large particles is sprayed. This improves the lubrication performance between the tool and the workpiece. Further, mist of fine particles is easily vaporized in the region to be processed, and the cooling performance is excellent.

Preferred conditions for generating a mist of fine particles in such a mist generation device 50 are as follows. First, the pressure of the air supplied from the connecting portion 90 is preferably in the range of 2.5 to 10 kgf / cm ² . This means that the pressure is 2.5 kgf / cm ²
If the pressure is smaller than 10 kgf / cm ² , the generated mist will collide with each other in the middle of the mist pipe and will be combined if the pressure is larger than 10 kgf / cm ^2. This is because the mist state cannot be maintained. Since the pressure of the air piped in the factory where the mist generating device 50 is usually used is 7 kgf / cm ² or less, such existing factory air may be used as it is.

The water-soluble cutting fluid supplied from the oil flow path 60 is preferably supplied at a pressure of 0 to ²⁰ kgf / cm ² at a flow rate of 3 to 30 cc / min.

Further, an oil flow passage 60 including a small diameter portion 62, a medium diameter portion 64, a large diameter portion 66, and a connecting portion 68, and an oil from a pump for supplying a water-soluble cutting fluid to the oil flow passage 60. It is preferable that the total volume with the piping is substantially equal to the amount of the water-soluble cutting fluid supplied per one pulse. This is because the water-soluble cutting fluid supplied by one pulse fills the inside of the oil flow path unit 60.

The inclination angle θ of the tapered peripheral surface 54 with respect to the central axis X of the oil flow path portion 60 is preferably 10 to 12 degrees. This is because the space V surrounded by the extension surface of the tapered peripheral surface 54 has a volume necessary for sucking the water-soluble cutting fluid from the oil flow path portion 60.

Here, when the mist was generated by setting the dimensions and the like of each part of the mist generating device 50 as follows, the following results were obtained.

That is, in the inner cylindrical portion 52, the length of the small diameter portion 62 along the X axis is 8 mm, and its diameter is 1 m.
m, the length of the middle diameter portion 64 is 9 mm, and the diameter is 1.5
mm, the length of the large diameter portion 66 is 16 mm, and the diameter is 5
mm, and the length dimension of the peripheral projection 58 is 10 mm,
A thread groove for screwing and connecting the oil pipe 18c is formed on the inner peripheral surface. The width of the air flow path 85 in the radial direction is about 3 mm.

The inclination angle θ of the tapered peripheral surface 54 with respect to the X-axis direction is set to 10 degrees, the length dimension along the X-axis direction is set to 20 mm, and the minimum diameter portion on the distal end side is set. The outer diameter of is set to 3 mm,
The outer diameter of the maximum diameter portion on the base end side is set to 10 mm.

On the other hand, the mantle portion 80 has its entire length (the connecting portion 8).
Except for (1), the distance from the tip of the ejection chamber 82 to the base end of the housing projection 88) is set to 80 mm.

The outer diameter of the ejection chamber 82 is 8 m.
m, the outer diameter of the housing body 86 is set to 16 mm, its length along the X-axis direction is set to 13 mm, and the length of the housing protrusion 88 is set to 10 mm. .

In the mist generating device configured as described above,
According to the air pressure 3kgf / cm ^Two, Water-soluble cutting fluid
Pressure 10kgf / cm^Two, At a flow rate of 5 cc / min.
When mist is generated under the condition of 50 pulses, 30 m
The mist could be supplied via the pipe.

Further, there are a case where the mist generated by the mist supply device is sprayed onto the region to be machined to perform the bite machining, and a case where the oil-based water-soluble cutting fluid flows down to the region to be machined and the bite machining is performed. Are as follows.

The conditions are as follows: the feed of the working tool is 0.3 mm / r,
This is a case where the peripheral speed is set to 150 m / min and the finishing allowance processing of 0.3 mm is performed. In the mist supply device, the air pressure is 3 kg / cm ² , and the water-soluble cutting fluid is supplied at 5 cc / min.
And a water-soluble cutting fluid (Mighty Mist (trade name), manufactured by Mighty Science Co., Ltd.) was used as the water-soluble cutting fluid.

As a result, when the oil-based cutting fluid was allowed to flow down in a liquid state, the flank was worn by 0.827 mm. On the other hand, when the mist generated by this mist supply device was sprayed, The surface wear was 0.131 mm, and the wear was smaller than when the oil-based water-soluble cutting fluid was allowed to flow down.

[0072]

As described above, according to the drilling method of the present invention, the mist of the water-soluble cutting fluid is supplied to the oil hole formed in the drilling tool, and the mist is formed from the tip of the drilling tool. Because it is jetted, mist is sprayed directly into the hole to be machined by the drilling tool, and it is possible to supply sufficient water-soluble cutting fluid for lubrication and cooling during drilling, and as a result, machining The efficiency is improved, and the life of the tool is prolonged.

According to the drilling apparatus of the present invention, a drilling tool having an oil hole penetrating from the base end side to the distal end side is rotatably supported, and a mist inlet and a mist inlet are supplied to the mist inlet. A drilling device main body in which a flow path for guiding the mist of the formed water-soluble cutting fluid from the base end side of the drilling tool to the oil hole is formed, and the generated mist is supplied to the mist inlet and the flow path and the oil hole are formed. And a mist generating device for jetting from the tip of the drilling tool through the hole, the mist is sprayed directly into the hole to be processed by the drilling tool, which is sufficient for lubrication and cooling during drilling. It becomes possible to supply a water-soluble cutting fluid, and as a result, machining efficiency is improved, and the life of the tool is extended.

As the mist generating device, an oil flow path portion for discharging the water-soluble cutting fluid supplied from the base end side to the front end side is formed, and the outer peripheral surface on the front end side is directed in the front end direction. A tapered peripheral surface whose outer diameter dimension is gradually reduced toward the outer peripheral surface, an outer jacket is provided so as to cover the tapered peripheral surface, and the tapered peripheral surface and the outer jacket are provided. An air flow path portion is formed along the tapered peripheral surface between the inner cylindrical surface and the inner cylindrical surface, and the air supplied from the air flow path base end side flows along the air flow path section to the inner cylinder portion distal side. And a mist is generated by supplying a water-soluble cutting fluid in a pulsed manner to the oil flow path portion, by using high-speed air supplied to the distal end side of the inner cylinder along the oil flow path portion. The air at the tip of the air passage opening is sucked in, Portion is formed. The water-soluble cutting fluid in the oil flow path is sucked by the low-pressure portion of the vortex, and mist is generated. Therefore, a mist composed of very fine particles is generated, so that the mist can be reliably supplied through an oil hole or the like of a drilling tool.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a drilling apparatus according to an embodiment of the present invention.

FIG. 2 is a front view showing a mist supply device.

FIG. 3 is a rear view showing the mist supply device according to the first embodiment.

FIG. 4 is an enlarged view of a main part of the drilling machine.

FIG. 5 is a side view showing a drill.

FIG. 6 is an end view taken along the line VI-VI of FIG. 5;

FIG. 7 is a view showing one step of drilling by the drilling apparatus.

FIG. 8 is a side view showing a tap.

FIG. 9 is a cross-sectional view showing a mist generation device.

FIG. 10 is a cross-sectional view showing an inner cylinder portion of the mist generation device.

FIG. 11 is a side view showing an outer jacket of the mist generation device.

FIG. 12 is an enlarged sectional view of a main part for explaining the principle of the mist generating device.

FIG. 13 is an enlarged sectional view of a main part for explaining the principle of the mist generating device.

FIG. 14 is a diagram illustrating a method of supplying a mist of a water-soluble cutting fluid according to a conventional example.

FIG. 15 is a diagram illustrating a method of generating a mist according to a conventional example.

[Explanation of symbols]

 Reference Signs List 50 mist generation device 52 inner cylinder portion 54 tapered peripheral surface 60 oil flow passage portion 80 outer jacket portion 85 air flow passage portion 110 rotation driving means 126 communication hole portion 130 oil seal portion 142 mist introduction port 150 drill 158 oil hole A Object G, F Channel E, D space

Claims (3)

[Claims] 1. A drilling method for drilling a workpiece with a drilling tool, wherein an oil hole penetrating from a base end to a tip end is formed in the drilling tool, and a water-soluble cutting fluid is provided. Drilling the workpiece while supplying the mist into the oil hole from the base end side of the drilling tool and ejecting the mist from the tip of the drilling tool. . 2. A drilling tool having an oil hole penetrating from a base end to a tip end is rotatably supported, and a mist inlet and a water-soluble cutting fluid supplied to the mist inlet are provided. A drilling device main body in which a flow path for guiding mist from the base end side of the drilling tool to the oil hole is formed, and the generated mist is supplied to the mist introduction port, and the mist is supplied through the flow path and the oil hole. And a mist generating device for ejecting the mist from the tip of the drilling tool. 3. An oil flow path portion for discharging the water-soluble cutting fluid supplied from the base end side to the front end side in the mist generation device, and the outer peripheral surface at the front end side is formed at the front end. The tapered peripheral surface has an inner cylinder part finished to a tapered peripheral surface whose outer diameter dimension is sequentially reduced in a direction, and an outer jacket is provided so as to cover the tapered peripheral surface. An air flow path portion is formed between the outer peripheral surface and the inner peripheral surface along the tapered peripheral surface, and the air supplied from the base end side of the air flow path portion is supplied along the air flow path portion to the distal end of the inner cylindrical portion. 3. The drilling apparatus according to claim 2, wherein the mist is generated by supplying water-soluble cutting fluid to the oil flow path portion in a pulsed manner while supplying the cutting fluid to the oil flow path.