JPH048450A - Spindle unit for machine tool - Google Patents

Abstract

PURPOSE:To keep off any dripping of a coolant into a spindle taper hole in relation to the setting of a tool holder and vice versa by feeding a flange part and a tool of the tool holder with the coolant from a center hole of a drawing bolt. CONSTITUTION:A passage P1 for a coolant of a drawing bolt 9 is reached to a check valve V from a connecting hole P2 via another connecting hole P3 and opened to a spindle front end face 2f and connected to a through-hole P4 of a tool holder TH. A tail end side of the connecting hole P3 is connected to a coolant supply source via a rotary joint. An air passage E2 is opened to a space 2c, a ring space (e) is connected to the air passage E2 at the connecting hole P3, the spindle tail end side is connected to a passage E1 installed in one side of a push-in ring 11, being opened to one side of the back of a push disk 11c. When an air supply source and the passage E1 are connected together simultaneously with the push-in ring 11 pressed by means of unclamping operation, air passes through a peripheral passage (e) of an air inlet cylinder 8 from the passage E1 of the ring 11, and it flows out to the space 2c by way of these passages E2, E3 in front of the spindle, thus a taper hole 2b is cleaned.

Description

Detailed Description of the Invention "Field of Industrial Application" The present invention is used in machining centers, boring machines, etc., to blow air when attaching and detaching tools and tool holders to the main shaft, and to spray coolant during cutting. Concerning improvements in spindle devices that can be supplied.

"Prior art and problems" A center through coolant 1-1 in which a coolant supply path is formed in the center hole of the draw interbolt of the main shaft, and coolant is spouted from the connection between the collet and the pull stud at the tail end of the tool at the center hole of the tool. A method is provided. In addition, a spindle cleaning device is provided which cleans the taper hole by blowing compressed air from an air supply source into the coolant supply path using a switching valve, instead of blowing air onto the inner surface of the spindle taper hole when replacing the knee and holder. has been done. This method of supplying both coolant liquid and air causes the coolant liquid accumulated in the coolant supply path of the draw interbolt to be blown out together with the air blower, causing a mistake and wetting the inner surface of the tapered hole, making it difficult to blow out the air. There are problems that reduce the effectiveness of

Therefore, as seen in Utility Model Publication No. 1-11408, for example, the coolant liquid supply path and the air supply path are separated, thereby eliminating wetting of the tapered surface by the coolant liquid during air blowing. However, coolant liquid remains at the connection between the tip of the draw interbolt and the tail end of the tool holder, and regardless of the presence of the check valve, it drips or is attracted to air blowing and wets the spindle taper hole. has not been completely resolved.

In addition, since the above two supply passages must pass through the draw interbolt inside the disc spring, the wall thickness of the draw interbolt must be made extremely thin to reduce its strength, so that it can withstand the tensile force of the draw interbolt. In addition, if the inner hole of the disc spring is enlarged to increase the shaft diameter of the draw interbolt, a special disc spring must be specially manufactured, which creates new problems that increase manufacturing costs. Also, 2
6. Problems and Means to be Solved by the Invention The present invention was made in view of the problems listed in L.

In addition to making the coolant liquid supply path and the air supply path completely separate, it is equipped with various supply sources that completely prevent coolant liquid from dripping into the main shaft taper hole and do not reduce the wall thickness of the draw interbolt. The task and purpose is to supply spindle devices.

The means for embodying the above problem M is to drill a coolant passage in a drawer bolt inserted in the main spindle, and the coolant passage in the drawer bolt is a coolant passage drilled in the main spindle on the tip side of the spindle. Connected to the passage, the front end surface of the main shaft is connected to the coolant passage of the tool holder, and the extreme side of the cooler passage in the drawer bolt is connected to a coolant supply source via a rotary joint from a pushing ring pushed by the unramp member. The air passage, which is connected to the main shaft and opens into the space of the collet, is formed by inserting an air introduction tube into the outer peripheral side of the disc spring installed in the rear part of the main shaft, and creating an air passage between the inner peripheral surface of the main shaft and the inner circumferential surface of the main shaft. Further, the air passage opening on the back side of the pushing ring at the tail end of the spindle is bored in the pushing cylinder of the unclamping member and serves as a main spindle device that connects with the air passage communicating with the air source during unclamping. be.

With the above means, in the spindle device of the present invention, coolant can be supplied from the center hole of the draw interbolt to the flange of the tool holder and the tool, and there is no dripping of coolant into the spindle taper hole when the tool holder is attached or removed. Also,
The air supply path is formed in the outer peripheral gap of the air introduction tube inserted into the outer circumference of the disc spring, and the large diameter air introduction tube can stably supply compressed air to the inner part of the taper hole without air flow resistance.

Embodiment FIG. 1 is a cross-sectional view showing a main spindle device of the present invention, and FIG. 2 is a cross-sectional view showing an unclamping device provided at the rear of the main spindle device and a joint for supplying coolant and air.

In Fig. 1, l is the spindle sleeve and the outer side is the spindle head 10.
The main shaft 2 is fixed to the central through hole 2a, and the main shaft 2 is rotatably supported on the inside by multiple rows of bearings 3.4.
A taper hole 2b into which the taper shank 5 of the tool holder (tool) TH is fitted is corrugated at the tip of the tool holder (tool) TH, and a space 2c is corrugated into which the ball 6 of the collet chuck escapes in the outer radial direction. A wide space 1v that accommodates the disc spring 7 and air introduction cylinder 8! 2d is corrugated. Reference numeral 9 denotes a drawer bolt inserted through the center through hole 2a and across the space 2b, and is connected to the center through hole 2a so as to maintain airtightness.
It is fitted through with a sealant interposed.

A plurality of balls 6 are arranged in an annular manner on the tip collet chuck so as to be able to expand and contract. Then, as shown in the figure, the draw interbolt 9 grips the pull stud tail end 5a of the tool holder TH with the ball 6 by the elastic force of the disk spring 7 and is bowed, and the unclamping member 30 described later When the user propels the draw interbolt 9 in the direction of the tool holder TH, the ball 6 moves into a wide space l7j1
2) Run to c and release the pull stud 5a of the tool holder. A large number of disc springs 7 are fitted from the middle of the draw interbolt 9 to the tail end, and the disc springs 7 on the end side are pressed against the step wall 2e so that the disc spring 7 on the tip side of the main shaft is brought into contact with the stepped wall 2e. It is locked to a pressing collar 11a of a pressing ring 11 that is screwed onto a tail end threaded portion 9a of the draw interbolt 9. Therefore, the draw interbolt 9 is moved to the tool holder TH by the elastic force of the built-in disc spring 7.
This is the same as the known configuration in which the disc spring is compressed by the push force from the unclamp member 30 of the tool holder TI (push ring to the side) 1, the draw interbolt is pushed in, and the tool holder is released. The locking pin is screwed onto the tail end of the main shaft, and restricts the stroke of the draw interbolt, which is propelled toward the rear end of the main shaft by a disk spring, with the restriction groove llb of the push ring 11, and the rotational force of the main shaft is It is provided by a power transmission system from a drive source to a gear 13 on the tail end side of the main shaft.

The coolant passage (hole) Pl drilled in the central axis of the draw interbolt 9 in the main shaft extends from a communication hole P2 perpendicular to the axial direction of the main shaft to a communication hole P in the axial direction on the main shaft tip side. It reaches the check valve V through the main shaft and opens at the front end surface 2f of the main shaft. Here, it is connected to a through hole P4 opened on the back side of the clamp 5a of the tool holder TH. The tail end side of P is connected to Ir! from the center of the back surface of the push ring 11 via a rotary joint RJ. 1
4 connects to a coolant fluid supply source (not shown).

On the other hand, the air passage (hole) E2 is located in the inner space 2 of the tapered hole 2b.
The air introduction tube 8 is fitted into the space which is open at C and into which the disc spring 7 is inserted, and an air passage is formed in the annular space (e) formed by this recessed outer peripheral surface and the space 2d. do. The annular space (e) is connected to the passage (hole) E2 through the communication hole E3, and the tail end side of the main shaft is connected to the passage E1 bored on one side of the pushing ring 11, and the back side of the pushing disk 1 ], c It is open to

Next, unclamp member 3 of the draw inter bolt 9
Explain 0. A connecting cylinder 31 is connected to the tail end of the spindle head 10,
A cylinder tube 32 is connected to this with its axis aligned with each other to form a housing. The connection [31 includes the push-in ring 1], and a rotary joint RJ is attached to its connection port 11cl, and a plumber 4 is provided. On the other hand, the cylinder tube 32
Inside, a cylinder C is provided on the rear side, and a piston 34 is airtightly supported by a flange 33 and a support ring 32a. The front end surface 34a of this piston 34 has a pressing cylinder 3
The rear end surface 35a of the tool holder T is screwed onto the rear end surface 35a of the tool holder T.
Unclamp H. In the figure, the piston 34 is moved back and the press cylinder 35 is separated from the push ring 11, so that the press cylinder does not interfere with the rotation of the main shaft, and the supply of liquid from the rotary joint RJ is performed. can.

The press cylinder 35 is provided with a connector 36 for receiving air from an air supply source, and this connector 36 is connected to the through hole 3Ga and opens at the front end surface 35b of the press cylinder 35. Therefore, in the state shown in Figure 1, air cannot be supplied to the main shaft 2 side, but when the press cylinder 35 presses the push ring 11 during unclamping as shown by the chain line,
The through hole 36a and the passage E□ of the restraining ring 11 are connected,
Compressed air from an air supply can be pumped.

"Operation" The spindle device 100 of the present invention will be explained from a state in which the tool holder TH configured as described above and shown in one figure is clamped in the slave hole 2b. In this state, the main shaft 2 can rotate and stop freely, and the rotary joints RJ, mp,, p2. p3.
Coolant liquid is supplied from the passage P4 opening to the flange 5b of the tool holder to the center hole (not shown) of the tool via the check valve (2). This coolant passage does not open into the space 2c of the collet 5 and the pull stud 5a, and the coolant does not affect the taper hole even when air is blown into the taper hole during tool exchange. On the other hand, taper hole 2 when changing tools
Air blowing in b is done by unclamping.

When the pressing cylinder 35 of the piston 34 presses the pressing ring 1 on the main shaft 2 side against the elastic force of the disc spring 7, both passages 36a,
E□ is connected, and compressed air is supplied from the air source in this state. That is, the air flow is caused by the push ring 1
], passes through the outer circumferential passage (e) of the air introduction cylinder 8, and flows out into the space 2c via the passages E, , E, in the front part of the main shaft. Due to this air outflow, the pressure within the space 2o increases,
When the tapered hole 2b is "licked" and pushed out, the tapered hole is cleaned.

After this, in order to clamp the tool holder TH, the piston 3
When 4 leaves work, the press cylinder 35 separates from the press ring 11,
Air supply ends.

“Change Example” The present invention is not limited to the above embodiment.

It is possible to change the design within the gist. For example, draw the installation location of the check valve ■ inside the tip of the interbolt 9 (a)
It is also possible to separately install the coolant liquid at the P side of the "connection" from the passage P1 of the draw interbolt 9 to the passage P2 of the main shaft 2.

At this time, a release rod for opening the check force L1 is provided at the tail end of the tool holder, and the release rod is opened and closed in response to attachment and detachment of the tool. Further, the annular space (e) formed by the air introduction tube 8 and the main shaft space 2d may be formed by widening the inner peripheral surface side of the main shaft 2 instead of recessing the outer periphery of the air introduction tube. .

[Effect] Since the present invention is constructed as described above, the coolant liquid does not leak into the space between the collet and the pull stud, and stable coolant supply can be ensured. Also,
The passage within the main shaft in the air supply means is formed by a wide space between the air introduction cylinder on the outside of the disc spring and the inner peripheral surface of the main shaft, so air flow resistance is extremely low, ensuring a stable and large amount of air supply. This eliminates problems such as making the wall thickness of the draw interbolt extremely thin and reducing its strength, or increasing the inner diameter of the disc spring more than necessary and requiring a special specification disc spring. A spindle device with a clean structure can be provided. Furthermore, since the air supply path to the main shaft is shared by the pressing cylinder of the unclamping member and the separating member of the pressing ring on the draw interbolt side, there is no need for a rotary joint in the air supply path, and durability is achieved with no air leakage. This has many advantages, such as a spindle device with a short overall spindle length that is excellent in terms of performance.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a spindle device of a machine tool of the present invention, and FIG. 2 is a sectional view showing an unclamping member. 100...Spindle device, 10...Spindle head, 2...Spindle, 2b...Tapered hole, 2C...Space, 2f...
Front end surface, TH...Tool holder, 5a...Pull stud -5b...Flange, 7...Disc spring, 8...Air introduction cylinder, 9...Draw interbolt, ]1...・Pushing ring, 30... Unclamping member, 34... Piston, 35... Pressing cylinder, RJ-・Single rotation joint, 36a
, Ell (e), E7. E,...air passage, P
XI P29 P39P4...Coolant passage,■・
··non-return valve.

Claims (1)

[Claims] (1) A coolant passage is drilled in the draw interbolt inserted into the main spindle, and the coolant passage in the draw interbolt is connected to the coolant passage drilled in the main spindle at the tip end of the main spindle, and the coolant passage is connected from the front end surface of the main spindle to the tool. The rear end side of the coolant passage in the draw interbolt is connected to the coolant passage of the holder, and is connected to a coolant supply source via a rotary joint from a pushing ring pushed by the unramp member, and is bored in the main shaft. The air passage that opens into the space of the collet is formed by inserting an air introduction tube into the outer circumferential side of the disk spring installed at the rear of the spindle to form an air passage between the inner circumferential surface of the spindle and the push-in ring at the tail end of the spindle. The main spindle device of a machine tool is configured such that the air passage opened on the back side of the unclamping member is connected to an air passage formed in a pressing cylinder of the unclamping member and communicating with an air source during unclamping.