JPH0647648A - Coolant feed device - Google Patents

Abstract

PURPOSE:To let coolant function as both coolant and lubricant with coolant successfully supplied to a cutting tool in such a way that no discharge pressure is lowered under the influence of centrifugal force even at the time of high speed revolution. CONSTITUTION:A push rod 13 is connected to the inner end section of a tool holder 10 while being penetrated through a spindle 9, and a coolant feed path 15 is bored therein in the axial direction. The tip end section of the spindle 9 is formed into a cylinder section 17 in the axial direction so as to be coupled in a piston 19 provided with a coolant port 18. An oil feed port 12a is bored in the tool holder 10 while being inclined to its axial direction in such way as to be communicated with the coolant port 18. A communication hole 21 is bored between the cylinder section 17 and the coolant feed path 15 in such a way that the piston 19 is pushed in, and sealant 22 is applied to the end face of the piston 19 in such a way that the periphery of the oil feed port 12a is sealed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coolant supply device for supplying a coolant (cutting oil) to a cutting tool inserted into a spindle of a machine tool such as a boring machine or a drilling machine.

[0002]

2. Description of the Related Art Conventionally, this type of coolant supply device is
It is configured as shown in FIGS. 10 and 11 (see Japanese Patent Laid-Open No. 3-117533).

That is, in FIG. 10 and FIG. 11, a taper shank b is attached to a main spindle (spindle) a of a machine tool such as a boring machine or a drilling machine, and a tip end opening of the taper shank b. A catching holder c is fitted in the portion b1, and an arcuate portion e having an arcuate cross section is formed inside the tip opening b1 of the tapered shank b. A locking portion e1 is formed in the middle. Further, a pair of front and rear bearings f is provided on the brim portion c1 of the catching holder c positioned in front of and behind the engaging portion e1 so as to swing, and the opening of the catching holder c is
For example, a cutting tool g such as a reamer or a drill (see FIG. 11) is inserted. Furthermore, this cutting tool g is provided with an oil supply hole g1.
In the above catching holder c located at the inner end of 1,
The coolant pipe d is fitted so as to supply the coolant (cutting oil). An adjusting cylinder i is elastically fitted in the tapered shank b located at the inlet of the coolant pipe d by a set screw j so as not to come out. Further, a seal ring k is attached to an outer peripheral opening of the adjusting cylinder i so as to abut on the catching holder c by an elastic force of a spring m so that the supply amount of the coolant can be adjusted. On the outer side of the tapered shank b, a coolant supply hole n is formed so as to be inclined forward. Furthermore, a ring-shaped coolant supply ring body o is fitted in a hermetically sealed manner on the outer periphery of the tapered shank b where the coolant supply hole n is located. The supply port p is connected to a coolant supply source (not shown) via a pipe joint q, and the coolant supply ring o is
The supply hole o1 is provided so as to communicate with the coolant supply hole n.

That is, the coolant supply ring o connects the coolant supply port p to the coolant supply source through the pipe joint q, and forms the supply hole o1 so as to communicate with the coolant supply hole n. These form a rotary joint r.

Therefore, the coolant supply device described above is
When cutting the work, by forcibly supplying the coolant from the coolant supply port p of the coolant supply ring o,
This coolant is supplied to the supply hole o1 and the coolant supply hole n, and is rotated at the same time as a main spindle (spindle).
By conquering the centrifugal force of the tapered shank b integral with a and press-fitting it to the outer side of the adjusting cylinder i, the seal ring k is pushed open against the elastic force of the spring m and from between the catching holder c. The coolant supply amount is adjusted and supplied, and the cutting tool g is passed through the coolant pipe d.
The oil is supplied to the oil supply hole g1 of the above to perform a cutting action.

[0006]

However, the coolant supply device described above has a rotation speed of about 4000 during cutting.
There are few problems at ~ 5000 rpm, but
When the rotation speed during cutting reaches a high rotation speed of about 6000 rpm or more, the lip of the oil seal wears and a leakage phenomenon occurs, which causes damage to the spindle b or replacement every time. Instead, the coolant is overcome by the centrifugal force of the rotating taper shank b and is press-fitted to the outside of the adjusting cylinder i, so that the coolant is supplied by further pressurizing so as to compensate for the decrease in the discharge pressure due to the centrifugal force. However, at a high rotational speed of about 6000 rpm or more, there is a problem that more leakage occurs due to wear of the lip of the oil seal.

The present invention has been made in view of the above-mentioned circumstances, and the axis of the main shaft (spindle) or the axis of the spindle is prevented so that the discharge pressure of the coolant is not lowered even when the rotational speed becomes high. Coolant is supplied along the vicinity of the core, and the piston is pressed against the end surface of the tool holder that is rotating at high speed with the hydraulic pressure of the coolant to seal it, and the coolant is supplied to the cutting tool for cooling and lubrication. An object is to provide a coolant supply device.

[0008]

According to the present invention, a tool holder having a cutting tool is provided at the tip of a spindle, and a push rod is connected to the inner end of the tool holder and the tool holder is fitted through the spindle. The push rod is provided with a coolant supply passage in the axial direction, a cylinder portion is formed at the tip of the main shaft in the axial direction, and a piston having a coolant hole is fitted in the cylinder portion. An oil supply hole is formed so as to be inclined in the axial direction so as to communicate with the coolant hole, and a communication hole is formed between the cylinder portion and the coolant supply path so as to push the piston, A seal member is attached to the end surface of the piston so as to seal around the oil supply hole.

[0009]

According to the present invention, at the time of cutting a work, a tool holder equipped with a cutting tool at the tip of a spindle is rotated at high speed, and a coolant is supplied from a coolant supply passage of a push rod along the axis of the spindle. Coolant is supplied to the tool while cooling the coolant and lubricating it while sealing the piston with the fluid pressure of the coolant on the end face of the tool holder by pushing the piston through the communication hole to prevent the discharge pressure from decreasing due to the influence of centrifugal force. Then, it has a cutting action.

[0010]

The present invention will now be described with reference to the illustrated embodiments.

In FIGS. 1 to 9A and 9B, reference numeral 1 is a machine frame (frame) having a cylindrical shape in a machine tool such as a boring machine or a drilling machine. A stator 3 of the drive motor 2 is provided in the middle, and a side plate 4 is attached to one side of the machine frame 1 where the stator 3 is located. A bearing 5 is provided on the side plate 4, and a holding cylinder 6 is attached to the front end portion of the machine frame 1 where the stator 3 is located.
Further, a plurality of bearings 7 are provided in the holding cylinder body 6, and a main shaft (spindle) 9 which is integral with the rotor 8 of the drive motor 2 is rotatable in the bearing 5 and each bearing 7. It is mounted on. Furthermore, a taper portion 9a is formed at the tip of the main shaft 9, and a tool holder 10 such as a taper shank is inserted and attached to the taper portion 9a. Further, as shown in FIG. 6, a cutting tool 11 such as a drill is inserted into the tip portion 10a of the tool holder 10, and the tool holder 10 in which the cutting tool 11 is positioned is located. An oil supply hole 12 is axially formed in the shaft center of so as to supply a coolant (cutting oil). Further, another oil supply hole 12a is formed in the tool holder 10 so as to be inclined in the axial direction so as to communicate with a coolant hole 18 described later, and the coolant is supplied to the cutting tool 11. .

On the other hand, the inner end portion 10 of the tool holder 10 is
A push rod 13 having a tubular shape is connected to the b through a ball locking member 14 and is fitted through the main shaft 9. The push rod 13 is provided with a coolant supply passage 15 in the axial direction. It is set up. Further, a large number of disc springs 16 are laminated and inserted in the hollow portion of the main shaft 9 outside the push rod 13, and the disc spring 16 pushes the push rod 13 outward (right in FIG. 1). People). Further, as shown in FIG.
A cylinder portion 17 is formed at the tip of the cylinder along the axial direction of the main shaft 9, and the cylinder portion 17 has
A piston 19 having a coolant hole 18 has a set screw 20
It is fitted so that it does not come out. Furthermore,
A communication hole 21 is formed between the cylinder portion 17 and the coolant supply passage 15 so as to push the piston 19 and supply oil.
A ring-shaped seal member 22 is provided on the end surface of the oil supply hole 1
It is attached so as to seal around 2a.

On the other hand, in FIG. 1, the side plate 4 is provided with a pair of support rods 23 in parallel with the main shaft 9, and in the middle of the both support rods 23, a cylinder member 24 is provided.
Is fitted. Further, a cylinder 25 is formed in the cylinder member 24, and the cylinder members 24 before and after the cylinder 25 are provided with respective oil supply ports 26a and 26b.
Are attached so that pressure oil can be supplied alternately. Further, the cylinder member 2 located on the side plate 4 side of the machine frame 1
As shown in FIGS. 1 and 5, each engaging portion 24
a is formed, and each of the engaging portions 24a is formed by the main shaft 9
Is locked by a locking member 27 screwed to one end of the.
Furthermore, as shown in FIGS. 1 and 7, the other end 13a of the push rod 13 has a joint pipe 2
8 is press-fitted and connected.

That is, at the other end of the joint pipe 28, as shown in FIGS. 8 and 9A and 9B, a peripheral groove 28b is formed on the outer periphery of the joint pipe body 28a.
A ceramic material 28c is attached to the circumferential groove 28b by thermal spraying, and the joint pipe 28 is prevented from seizing by the ceramic material 28c.

On the other hand, in the joint pipe 28,
Another push rod 29 is fitted and connected, and the piston tube shaft 3 is attached to the outer periphery of the other push rod 29.
0 is fitted coaxially. Further, a piston 31 is provided on the piston pipe shaft 30 in which the cylinder 25 is located, and the piston 31 alternately supplies the pressure oil from the respective oil supply ports 26a and 26b, so that in FIG. , And slides leftward and rightward along with the other push rods 29. Furthermore, an air supply passage 32 is formed in the other push rod 29 so as to communicate with the outer circumference of the joint pipe 28. The air supply passage 32 supplies compressed air to prevent coolant from leaking. The air supply passage 32 is connected to an air supply port 33 attached to the cylinder member 24.

In FIG. 1, a protective cylinder 34 is inserted around the outer periphery of the holding cylinder 6, and each bearing 7 of the holding cylinder 6 is lubricated by an oil supply pipe 35. It is plumbed.

The operation of the present invention will be described below.

Therefore, at the time of cutting the work, the tool holder 1 having the cutting tool 11 inserted into the tip of the spindle 9 is provided.
0 is rotated at a high speed, and the coolant is supplied from the coolant supply passage 15 of the push rod 13 along the axis of the main shaft 9. Further, the coolant is pushed through the communication hole 21 to push the piston 19, and the influence of centrifugal force is exerted. The discharge pressure due to is not lowered, and the seal member 22 attached to the end portion of the piston 19 is pressed against the end surface of the piston 19 by the hydraulic pressure of the coolant to seal the coolant and supply the coolant to the cutting tool 11. Cools and lubricates.

On the other hand, by supplying pressure oil from each oil supply port 26a, the piston 31 is moved to the piston tube shaft 30.
At the same time, the push rod 29 is slid to the left in FIG. Then, the other push rod 29 pushes against the resilience of the disc spring 16 in which the push rods 13 are laminated to push the tool holder 10 forward.

On the other hand, the compressed air in the air supply passage 32 of the other push rod 29 is supplied to the outer circumference of the joint pipe 28 to seal the coolant leakage.

[0021]

As described above, according to the present invention, the tool holder provided with the cutting tool is provided at the tip of the spindle.
A push rod is connected to the inner end of the tool holder and is fitted through the main shaft.A coolant supply passage is axially bored in the push rod, and a cylinder is attached to the tip of the main shaft in the axial direction. A piston having a coolant hole is fitted into the cylinder portion, and an oil supply hole is formed in the tool holder so as to be inclined in the axial direction so as to communicate with the coolant hole. A communication hole is formed between the supply passage and the piston so as to push the piston, and a seal member is attached to the end surface of the piston so as to seal around the oil supply hole, and along the axis of the main shaft. Since it is supplied, not only does the discharge pressure of the coolant not drop due to the influence of centrifugal force even at high speed rotation, but the piston is sealed with the coolant fluid pressure on the end face of the tool holder. While the fueling to cooling and lubricating action of the coolant to the cutting tool while, has excellent effects such as can be sealed while using the fluid pressure of the coolant effectively properly.

[Brief description of drawings]

FIG. 1 is a sectional view of a coolant supply device and a spindle according to the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is an enlarged cross-sectional view showing a main part of the present invention.

FIG. 4 is a rear view of the coolant supply device of the present invention.

5 is an enlarged cross-sectional view taken along the chain line AA of FIG.

FIG. 6 is an enlarged cross-sectional view showing a state in which a cutting tool is attached to the present invention.

FIG. 7 is an enlarged sectional view of a chain circle B portion in FIG.

FIG. 8 is an enlarged sectional view of a joint pipe incorporated in the present invention.

FIG. 9 is a view for explaining the structure of a joint pipe incorporated in the present invention.

FIG. 10 is a sectional view of a conventional coolant supply device.

FIG. 11 is a side view of another conventional coolant supply device.

[Explanation of symbols]

 9 Spindle 10 Tool Holder 11 Cutting Tool 12a Oil Supply Hole 13 Push Rod 15 Coolant Supply Channel 17 Cylinder Part 18 Coolant Hole 19 Piston 21 Communication Hole 22 Seal Member 28 Joint Pipe 29 Push Rod 32 Air Supply Channel

Claims (2)

[Claims] 1. A tool holder equipped with a cutting tool provided at the tip of a spindle, a push rod connected to the inner end of the tool holder and fitted through the spindle, A coolant supply passage axially bored in the push rod, a cylinder portion axially formed at the tip of the main shaft, a piston having a coolant hole fitted in the cylinder portion, and the tool holder An oil supply hole formed so as to be inclined in the axial direction so as to communicate with the coolant hole, and a communication hole formed so as to push the piston between the cylinder portion and the coolant supply passage. And a seal member attached to the end surface of the piston so as to seal around the oil supply hole. 2. A joint pipe connected to the other end of the push rod, another push rod fitted and connected to the joint pipe, and the other push rod communicating with the outer circumference of the joint pipe. 2. The coolant supply device according to claim 1, further comprising an air supply passage formed so as to supply compressed air to seal the coolant.