JP2003039213A - Mechanism for switching coolant and air blow in tool clamp in portion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set up an air flow passage as an annex to a coolant flow passage for cleaning the periphery of a collet arranged in the shape of a ring and a tapered hole of a main shaft. SOLUTION: This mechanism is provided with a member for opening and closing the coolant flow passage forced to open the coolant flow passage when a draw bar is pulled up, and forced to close the coolant flow passage when a tool holder is inserted at the tip of the draw bar, and moreover, a member for opening and closing the air flow passage forced to open a flow passage for ejecting air cylindrically from the clearance of the collet from the outer peripheral portion of the tip in the draw bar toward the tapered hole by pushing down the draw bar, and by inserting the tool holder while the collet is open when the coolant flow passage is closed, and forced to close the air flow passage by interlocking with pulling-up when the tool holder is fittingly fixed by pulling up the draw bar at the outer peripheral portion of the tip in the draw bar, in the mechanism capable of fittingly fixing the tool holder on the main shaft via the collet by pulling up the draw bar inserted through the bore in the main shaft and used to supply the coolant from a draw bar to a center bore in the tool holder in the machining center.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air blow mechanism of a tool clamp portion of a spindle for mounting a tool in a machine tool.

[0002]

2. Description of the Related Art With the introduction of automatic peripheral equipment such as ATC into numerically controlled machine tools, automation of machining has dramatically advanced, and accordingly, the frequency of exchanging machining tools and measuring instruments on the machine tool spindle is remarkable. Is increasing. At the time of replacement, it is necessary that the outer peripheral surface of the tool holder itself and the taper hole of the main shaft be surely cleaned and air-blown.

FIG. 4 is a sectional view of a coolant mechanism of a tool clamp portion according to the prior art. In FIG. 4, a drawbar 102 is inserted through a shaft center hole of a main spindle 101 supported by a main spindle head of a known machining center or the like, and a piston cylinder member (not shown) for pressing the drawbar 102 is provided at a rear end portion of the main spindle 101. Has been. When the tool holder 103 is mounted in the spindle taper hole 101a by ATC, the draw bar 102 is pulled up by the bending force of the stacked disc springs 104 to fit the tool holder 103.

When the tool holder 103 is detached from the main shaft 101, pressure oil is supplied to the rear chamber of the above-mentioned piston cylinder member to push the drawbar 102 against the force of the disc spring 104, and the drawbar 102 is provided at the tip of the drawbar 102. Collet 10
5, the tool holder 103 can be removed from the spindle 101. A new tool holder 103 is attached to the spindle 101.
When the supply of pressure oil to the piston cylinder member is switched to the front chamber, the flexure of the disc spring 104 increases, the draw bar 102 is pulled up and the collet is closed, and the tool holder 103 is pulled up to feed the spindle taper hole. Complete the fitting.

The drawbar 102 is provided with a central flow passage for the coolant and air blow at the axial center thereof, and a collet 105 divided into a ring-shaped spring 106 is provided at the tip end portion thereof.
The collet holder 107, which is held by the outer peripheral portion of the
It is screwed together with 07b and is integrally configured. A large-diameter hole 107a is formed on the rear end side of the center through hole of the collet holder 107, and a front end surface of the large-diameter hole 107a is stretched and positioned by a collar 108b and a spring 109, and the tip is projected from the collet holder 107. Thus, the hollow connecting pipe 108 is inserted into the center through hole 107c.

In the upper half of the center line shown in FIG. 4, the drawbar 102 advances to open the collet 105, and the pull stud 110 of the tool holder 103 opens.
It shows a state where it is possible to easily escape from. Tool holder 1
After removing 03 from the main shaft 101, the cleaning air supplied to the central flow path 102a of the drawbar 102 passes through the discharge hole 108a of the connecting pipe 108 and the tool holder 1
03, and the taper surface 101a of the main shaft 101
Cleaning.

Next, the lower half of the center line is the drawbar 102.
Is pulled up, collet 105 is closed, and tool holder 1
03 pull stud 110 is gripped and tool holder 103
It shows a state in which the taper shank is fitted and fixed to the taper surface 101a. The tip of the connecting pipe 108 has a pull stud 1
It is fitted into the end face hole of 10, and the spring 109 is further compressed to prevent the coolant from leaking from the connecting portion of the connecting pipe 108 and the pull stud 110, thereby ensuring the supply of the coolant.

[0008]

As described in the prior art, air is supplied before the shank of the tool holder 103 is fitted on the main shaft 101 to supply the central flow passage 10 of the draw bar 102.
Even when cleaning the inner surface of the taper hole 101a of the main shaft 101 from 2a, the connecting pipe 108 pulls the pull stud 1
You can only use the air flow until you engage 10.
After engagement, the air is only discharged through the axis of the pull stud 110 and the tool holder 103. Even if the tip shape of the connecting tube 108 is devised to widen the air ejection passage, its effect is limited.

Therefore, it is not possible to expect a sufficient effect for cleaning the inner surface of the tapered hole 101a only by supplying air to the flow path of the coolant instead of the coolant.
Further, regardless of the shape of the tip of the connecting tube 108, the peripheral portion of the collet 105 located behind the connecting tube 108 cannot be cleaned. Further, there is a problem that the coolant is accumulated around the collet 105 and these cannot be cleaned.

The present invention has been made in view of the above problems of the prior art, and its object is to:
A coolant channel opening / closing member that opens the flow channel when the draw bar is pulled up and closes the flow channel when the tool holder is inserted into the tapered hole is provided at the tip of the draw bar, and further on the outer peripheral portion of the tip of the draw bar. When the drawbar is pushed down and the collet is open, the flow path that allows air to blow out in a cylindrical shape is opened in the direction of the taper hole, and when the drawbar is pulled up and the tool holder is fitted and fixed, the cylindrical flow path is closed in conjunction with this. A mechanism for switching between a coolant and an air blow of a tool clamp portion provided with an air passage opening / closing member.

[0011]

In order to achieve the above object, the invention according to claim 1 of the present invention fits the tool holder to the spindle through the collet by pulling up the draw bar inserted in the spindle center hole. In the mechanism that supplies the coolant from the draw bar to the center hole of the tool holder, the coolant flow path is opened so that the flow path is opened when the draw bar is pulled up and the flow path is closed when the tool holder is inserted into the spindle center hole. When the coolant passage opening / closing member provided at the tip portion of the draw bar to be opened and closed and the tool holder is inserted into the main shaft to close the coolant passage and supply blowing air, the air is opened and closed in the coolant passage. An air flow path, which blows out in the direction of the taper hole, opens through a flow path provided in the outer peripheral portion of the member, and the tool holder is fitted onto the main shaft to supply the coolant. When the drawbar is pulled up, the air flow path is closed in conjunction with the pulling up of the drawbar, and the air flow path opening / closing member is configured to open the coolant flow path. The air is blown into the taper hole for cleaning.

According to the first aspect of the present invention, the coolant passage opening / closing member is provided at the tip portion of the draw bar, and the air passage opening / closing member is provided on the outer periphery of the coolant passage opening / closing member. The coolant passage opening / closing member is configured to temporarily close the coolant passage when the tool holder is inserted and open the coolant passage when the tool holder is fixed by pulling up the draw bar. Further, the air flow passage opening / closing member is configured to open the air flow passage when the drawbar advances and close the air flow passage when the drawbar is pulled up. The air flow path opening / closing member is configured so that air can be blown into a cylindrical shape in the direction of the taper hole from the gap of the collet arranged in a ring shape, so just before inserting the tool holder into the spindle. Air can be blown into the gap between the slight taper holes formed to effectively clean the periphery of the collet and the taper hole.

According to a second aspect of the present invention, the tool holder can be fitted to the main shaft via the collet by pulling up the draw bar inserted in the main shaft center hole, and the coolant is supplied from the draw bar to the center hole of the tool holder. The front end face of the drawbar is inserted into the center hole of the drawbar so that the forward end is defined by the front face of the collar coming into contact with the front part of the large-diameter hole formed in the center hole of the drawbar, and the tip is the front end face of the drawbar. A more protruding connecting pipe with a collar and a connecting rod that is housed in the large-diameter hole and faces the connecting pipe and is fitted into the rear end hole of the pipe to form a valve rod that can be closed. An on-off valve with a flange in which a cutout portion that serves as a flow path is formed in the flange that contacts,
A spring that is stretched between the connecting pipe and the on-off valve and constantly presses the flange to the latter stage of the large diameter hole, and an outer peripheral surface corresponding to the large diameter hole and the main shaft hole into which the collet is inserted. A cylindrical flow path formed of a peripheral surface, a radial flow path that connects the cylindrical flow path with the large diameter hole, and prevents outflow of coolant from the cylindrical flow path when the draw bar is pulled up. Therefore, a seal provided on the outer peripheral surface is included, and when the tool holder is inserted into the main shaft, the connecting pipe is pushed, the valve rod is engaged, the coolant flow passage is closed, and air is supplied instead of the coolant. In this case, air is blown from the gap between the collets into the tapered hole to clean the tapered surface.

According to the second aspect of the present invention, the connecting pipe, the on-off valve and the connecting pipe inserted into the large-diameter hole formed at the tip portion of the drawbar are provided.
A coolant flow passage opening / closing member is constituted by a spring, and a cylindrical flow passage formed by an outer peripheral surface corresponding to a large diameter hole and an inner peripheral surface of a spindle hole, a radial flow passage communicating from the large diameter hole to the cylindrical flow passage. An air passage opening / closing member is constituted by a seal provided on the outer peripheral surface for preventing the coolant from flowing out. The elements composing each opening / closing member are compactly gathered at the tip portion of the draw bar. The opening / closing member is operated by inserting the tool holder, pulling up the draw bar and advancing. The effect of cleaning is the same as that described in claim 1.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a coolant / air blow switching mechanism of the tool clamp portion provided at the tip of the spindle after the tool bar is opened by opening the collet by removing the tool holder, and FIG. 2 is a diagram in which the tool holder is inserted into the spindle. When the coolant flow path is closed and the air flow path is open, a cross-sectional view of the coolant and air blow switching mechanism of the tool clamp part is shown in FIG. 3. The draw bar is pulled up, the tool holder is fitted and fixed to the main shaft, and the air blow flow path is closed. FIG. 6 is a cross-sectional view of a coolant and air blow switching mechanism of a tool clamp portion in which a coolant passage is opened.

[Embodiment] In FIGS. 1 to 3, a coolant passage opening / closing member is provided as an element 1 of the invention at a tip portion of a draw bar 2. The outline of the coolant flow passage opening / closing member includes a connecting pipe 8, an opening / closing valve 11, and a spring 9. The coolant passage is configured to open and close in a large-diameter hole 7a formed in the axial center of the tip portion of the drawbar 2.

An air passage opening / closing member is provided as an element 2 of the invention on the outer peripheral portion of the tip of the draw bar 2.
The outline of the air flow path opening / closing member is a drawbar 2, a cylinder 12,
The O-rings 13A and 13B are included. Air is passed through the cylindrical air passage formed in the outer peripheral portion of the tip of the drawbar 2 from the large-diameter hole 7a, and the cylindrical air passage is opened and closed in conjunction with the forward movement and pulling up of the drawbar 2. In addition, the drawbar 2 and the collet holder 7 are screwed together to form a screwing portion 7.
The leading end portion of the drawbar 2 that forms the large diameter hole 7a with c is the same as the configuration described in the related art, and the description thereof is omitted.

Next, the structure of the coolant passage opening / closing member will be described. The coolant passage opening / closing member is formed in a large diameter hole 7 a formed at the tip of the draw bar 2. Large diameter hole 7
a is a collet that shares the same axis with the tip of the drawbar 2 that is inserted into the center hole 1a of the main shaft 1 and has a coolant passage hole 2a formed in the shaft center and the drawbar 2 that is provided with the collet 5 at the outer peripheral portion. The holder 7 and the holder 7 are integrally connected by a screwing portion 7c.

The collet 5 is divided into a plurality of segments, which are bundled by two ring-shaped springs 6 at the base thereof and held on the outer peripheral cylindrical surface of the collet holder 7 at a uniform pitch. The front end of the large-diameter hole 7a is defined by the front surface of the collar 8b coming into contact with the front stage 7d, and the hole 7b is formed coaxially with the large-diameter hole 7a from the front stage 7d toward the front end of the drawbar 2.
The pipe portion is inserted into the housing, and the connecting tube 8 with a collar, the tip of which is projected from the front end surface 7h, is housed.

Further, a valve rod 11a is formed at one end which is fitted in the rear end hole 8a of the connecting pipe 8 and faces the rear end hole of the connecting pipe 8 to close the rear end hole. Contact flange 11b
An opening / closing valve 11 with a flange, through which a cutout portion is formed in the outer peripheral portion thereof, through which a fluid can pass is housed in the large diameter hole 7a. A spring 9 which is stretched between the rear end surface of the collar 8b of the connecting pipe 8 and the flange 11b and which constantly presses the on-off valve 11 to the rear stage of the large diameter hole 7a is inserted.

When the tool holder 3 (FIG. 2) is inserted into the spindle taper hole 1a, the connecting tube 8 is pushed rearward by the pull stud 10 against the force of the spring 9 to connect the valve rod 11a of the on-off valve 11. The coolant passage opening / closing member is configured to fit into the rear end hole 8a of the pipe 8 to close the passage. Tool holder 3
Since the drawbar 2 is pulled up by the force of the disc spring 4 and the opening / closing valve 11 is moved rearward by the force of the spring 9, the valve rod 11a escapes from the hole of the connecting pipe 8. Then the coolant channel is opened.

Next, the air passage opening / closing member will be described. The air flow path opening / closing member corresponds to the large diameter hole 7a formed in the tip portion of the drawbar 2, and the collet holder 7 and the outer peripheral surface 7e formed outside the threaded portion 7c of the drawbar 2 and the collet 5.
A cylindrical flow path 2b is formed by the inner peripheral surface of the cylinder 12 fitted in the hole 1b of the main shaft 1 into which is inserted.

The large-diameter hole 7a and the cylindrical flow path 2b are connected by a radial flow path 2c. The draw bar 2 is pulled up by the disc spring 4, the shank portion 3c of the tool holder 3 is fitted and fixed in the spindle taper hole 1a, and the coolant is supplied from the cylindrical passage 2b. The O-ring 13 with the radial flow path 2c sandwiched between the surfaces 7e
A and 13B are annularly mounted. When the draw bar 2 is pulled up, one O-ring 13A is fitted in the cylinder 12, and therefore acts together with the other O-ring 13B to prevent the coolant from flowing into the spindle center holes 1c and 1d.

When the drawbar 2 moves forward, the air passage opens in the inner surface gap between the O-ring 13A and the cylinder 12, and the air can be discharged toward the collet 5 in the cylindrical passage so that the passage is opened. To be done. Further, the air flow path opening / closing member is configured such that the draw bar 2 retracts and the cylindrical flow path is closed by the O-rings 13A and 13B to close the air flow path. Note that the O-ring 13B is always airtight between the cylinder and the draw bar, and the O-ring 13B prevents backflow into the main shaft at the time of air blow, and escapes from the cylinder 12 to supply coolant, and the main shaft 1b, It prevents leakage to 1c and 1d.

Next, the operation of the coolant and air blow switching mechanism of the tool clamp portion of the present invention constructed as described above will be described. Pressure oil is supplied to the rear chamber of the cylinder member, and as shown in FIG. 1, the draw bar 2 is moved forward to open the collet 5 and the tool holder 10 is removed. In this state, the leaked coolant may remain near the collet 5. Around the ring-shaped spring 6 that holds the collet 5, the accumulated coolant is not removed unless the drawbar 2 is pulled out from the main shaft 1 and cleaned. In this state, both the coolant flow path and the cylindrical air flow path are open.

[Operation of Air Flow Opening / Closing Member] As shown in FIG. 2, supply of air is started from the air flow path of the draw bar 2 connected to a pressure air source (not shown). The tool holder 3 is exposed to the spindle taper hole 1a by means such as ATC, the pull stud 10 and the connecting pipe 8 are engaged with each other, and the connecting pipe 8 is pushed against the force of the spring 9 to push the valve rod 3a to the rear end 8a. The coolant passage is closed by fitting and closing the on-off valve 11. The air supplied to the center hole 2a of the drawbar 2 is pressed against the spring 11 at the rear stage of the large diameter hole 7a by the flange 9b of the on-off valve 11.
It reaches the large diameter hole 7a through the notch. The air flowing into the large diameter hole 7a passes through the radial flow passage 2c and is guided to the cylindrical flow passage 2b. Drawbar 2 is located at the front end, so O-ring 13
A has escaped from the cylinder 12 and the air flow path is open,
The air that has flowed into the cylindrical gap 2b is jetted from the gap of the collet 5 toward the tapered hole 1a of the main shaft 1 because the O-ring 13B prevents the air from flowing back to the center hole of the main shaft. As the gap between the taper of the shank of the tool holder 3 and the tapered hole of the main shaft 1 becomes smaller due to the subsequent insertion of the tool holder 3, the flow velocity of the air passing through the gap increases and the cleaning effect also increases.

[Operation of Coolant Channel Opening / Closing Member] As shown in FIG. 3, the supply of air to the drawbar 2 is stopped, the supply of pressure oil from a cylinder member (not shown) is switched to the front chamber, and the piston is retracted to move the disc spring 4 The pull bar 2 is pulled up by the force of and the shank portion 3c of the tool holder 3 is fitted into the spindle taper hole 1a through the collet 5. By pulling up the draw bar 2, the O-ring 13A of the cylindrical air flow channel is engaged with the inner surface of the cylinder 12, and the leakage of the coolant from the cylindrical flow channel 2b is prevented except for the large diameter hole 7a and the radial flow channel 2c. To be done. Further, as the draw bar 2 is pulled up, the on-off valve 11 is also pushed up by the pushing force of the spring 9, and the valve rod 11a is not fitted into the rear end hole 8a of the connecting pipe 8 in the large diameter hole 7a, and the coolant flow passage is be opened. Therefore, when the coolant is supplied from the draw bar 2 at the start of processing,
It becomes possible to supply the coolant to the central hole of the tool holder 3 via the pull stud 10.

[0028]

Since the coolant and air blow switching mechanism of the tool clamp portion according to the present invention is constructed as described above, the following effects can be obtained.

According to the first aspect of the present invention, the coolant flow passage opening / closing member and the air flow passage opening / closing member are formed in the space in which the conventional drawbar and collet-related parts are housed, so that a large change is required. It is easy to apply to conventional machines. Conventionally, when a used tool was removed from the spindle, the coolant that had accumulated around the collet gradually propagated along the tapered hole surface and dropped, causing the problem that the inner diameter surface of the tapered hole was easily contaminated. It turned out to be effective in solving the problem. According to the present invention, the coolant passage and the air passage are automatically switched in association with the attachment of the tool holder by the ATC, and the dirt around the tapered surface and the collet can be reliably cleaned by air blow.

According to the second aspect of the invention, the number of elements forming each opening / closing member is small, and stable operation can be expected. By opening and closing the on-off valve from the rear end hole of the connecting pipe, the coolant flow passage is opened and closed, and while the coolant flow passage is closed, air is supplied from the center of the drawbar to the cylindrical air flow passage provided behind the collet. The air is ejected in a cylindrical shape from the rear of the collet toward the fitting gap between the spindle taper hole and the tool holder shank, and the air passing through this gap becomes a high-speed fluid, and a good cleaning effect can be obtained. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a coolant / air blow switching mechanism of a tool clamp portion provided at the tip of a spindle after a draw bar is advanced to open a collet and a tool holder is removed.

FIG. 2 is a cross-sectional view of a coolant / air blow switching mechanism in a tool clamp portion in which a coolant passage is closed and an air passage is opened by inserting a tool holder into a spindle.

FIG. 3 is a cross-sectional view of a coolant / air blow switching mechanism of the tool clamp portion in which the air blow passage is closed and the coolant passage is opened by pulling up the draw bar and fitting the tool holder to the main shaft.

FIG. 4 is a cross-sectional view of a coolant mechanism of a tool clamp portion according to a conventional technique.

[Explanation of symbols]

1 spindle 2 drawbars 3 Tool holder 5 collets 6,9 spring 7 Collet holder 8 connecting tubes 10 pull studs 11 on-off valve 12 cylinders 13A, 13B O-ring

Claims (2)

[Claims] 1. A mechanism in which a tool holder can be fitted to a spindle through a collet by pulling up a drawbar inserted in a spindle center hole and a coolant is supplied from the drawbar to the center hole of the tool holder, and the drawbar is pulled up. Is a coolant channel opening / closing member provided at the tip portion of the draw bar for opening / closing the coolant channel so as to close the channel when the tool holder is inserted into the spindle center hole, and the tool holder When the blower air is supplied by closing the coolant flow passage by inserting it into the main shaft, the air flow passage in which the air is ejected in the direction of the taper hole through the flow passage provided in the outer peripheral portion of the coolant flow passage opening / closing member. When the tool holder is fitted to the main shaft and the coolant is supplied, the air flow path is closed in conjunction with the pulling up of the draw bar, and A tool clamp portion characterized by including an air flow passage opening / closing member configured to open a coolant flow passage, and closing the coolant flow passage to eject air cylindrically from a gap between collets into a tapered hole for cleaning. Coolant and air blow switching mechanism. 2. A mechanism in which a tool holder can be fitted to a spindle through a collet by pulling up a draw bar inserted in a spindle center hole to supply coolant from the draw bar to the tool holder center hole. The front of the collar is in contact with the front of the large-diameter hole formed in the middle, the forward end is defined, and it is inserted axially movably into the center hole of the drawbar and the tip is connected from the front end surface of the drawbar with a collar. A pipe and a valve rod that is housed in the large-diameter hole, faces the connecting pipe, and is fitted into the rear end hole of the pipe to form a valve that can be closed to form a flow path in a flange that comes into contact with the latter stage of the large-diameter hole. An on-off valve with a flange formed with a notch, a spring that is stretched between the connecting pipe and the on-off valve and constantly presses the flange to the latter stage of the large diameter hole, and an outer periphery corresponding to the large diameter hole. The surface and the collet are interpolated A cylindrical flow path formed by the inner peripheral surface of the spindle hole, a radial flow path that connects the cylindrical flow path and the large diameter hole, and a coolant from the cylindrical flow path when the draw bar is pulled up. And a seal provided on the outer peripheral surface to prevent the outflow of fluid, and when the tool holder is inserted into the spindle, the connecting pipe is pushed and the valve rod engages to close the coolant flow path and replace it with coolant. A mechanism for switching between coolant and air blow in the tool clamp section, characterized in that, when air is supplied by means of air, air is blown from the gap between the collets into the taper hole to clean the taper surface.