JP3062353U - Tool holder - Google Patents

Abstract

(57) [Problem] To provide a tool holder which can be strongly held on a spindle 20 of a machine tool and can perform high-precision cutting even if a pulling force is small. An elastic member (7) is interposed between a rear end of a flange (4) provided on the front side of a shank (3) of a holder body (2) and a front end of a tapered cone fitted to the shank (3). In the tool holder whose end face is supported by the stopper member 9 on the shank part 3, the outer circumference of the cone 8 having a small diameter on the rear side is formed by the inner circumferential surface 21 of the taper hole 21 of the spindle 20.
a, the taper between the inner peripheral surface of the cone 8 and the outer peripheral surface of the shank portion 3 is set to be equal to each other at a smaller angle than the outer peripheral taper of the cone 8 so that the rear side has a smaller diameter. As a result, the diameter of the cone 8 is increased, and the outer peripheral surface of the cone 8 can be strongly held on the inner peripheral surface of the tapered hole 21.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a tool holder that is detachably mounted on a spindle of a machine tool.

[0002]

[Problems to be solved by the invention]

 In the conventional tool holder, the shank is tapered with a small outside diameter on the rear side, a tapered hole with a small inside diameter on the rear side is formed at the front end of the spindle of the machine tool, and the shank portion of the tool holder is rearwardly drawn by the retracting member. The tool holder is attached to the spindle by pulling it into the side. However, a gap is provided between the flange provided on the front side of the shank portion of the tool holder and the front end face of the spindle, and the shank is formed only by the tapered outer peripheral surface of the shank portion and the tapered hole inner peripheral surface of the spindle. Since the part was constrained, it was not possible to hold the shank with a large force, and satisfactory cutting could not be performed in high-speed rotation or low-speed heavy cutting. Therefore, by applying an end surface constraint to the front end surface of the spindle, which presses the rear end surface of the flange portion provided on the front side of the shank portion of the tool holder, a constraint by the outer peripheral surface having the taper and the inner peripheral surface of the tapered hole, Some were designed to increase the binding force. However, in order to achieve the above configuration, the manufacturing tolerance must be severe, which increases the cost.If the spindle is used for a long period of time, the tapered hole needs to be polished again. In the case of re-grinding, since the tapered hole expands, only the restriction by the flange portion of the tool holder and the end face of the spindle is made, and the tapered portion does not contact, and the tool oscillates and cannot be used. Also, when the spindle is rotated at a high speed, the front end of the spindle expands due to the centrifugal force due to the tapered hole, the restraining force due to the tapered hole decreases, the tool held by the tool holder vibrates, and the machining accuracy decreases.

Therefore, a straight portion is provided on a shank portion of a holder body of a tool holder having a flange portion, a taper cone is fitted therein, and a disc spring is interposed between a rear end surface of the cone and a front end surface of the shank portion. Then, by preloading the tapered cone, the outer peripheral surface of the tapered cone having a small outer diameter on the rear side is pressed against the inner peripheral surface of the tapered hole having a small outer diameter on the rear side of the spindle, and the holder body is positioned on the rear side of the spindle. Some results can be obtained and the fabrication is relatively easy.However, unless the retraction force of the holder body is increased, the inner peripheral surface of the tapered hole cannot sufficiently constrain the taper cone. . Also, a two-stage straight portion is formed on the outer periphery of the shank portion of the holder body, with a large-diameter end portion and a small-diameter end portion. However, since the inner peripheral surface of the tapered cone is straight, there is a problem that sufficient effects cannot be obtained unless the holder body is pulled in with a strong pulling force. there were.

This invention solves the above-mentioned problem, and even if the pull-in force of the holder main body is relatively small, the shank portion outer peripheral surface of the holder main body and the inner peripheral surface of the tapered cone closely fitted to the shank portion are fitted. By forming a taper with a smaller angle than the taper angle of the tapered hole inner surface of the spindle and the taper cone outer surface of which the rear side has a smaller diameter, the pulling force of the pulling member engaging with the holder body causes the shank portion and the taper cone to move. And are locked in a locked state by the wedge effect, and the lining force of the taper cone outer peripheral surface is applied to the inner peripheral surface of the taper hole of the spindle, and the retracting force, which is the instantaneous point of the retracting force, is maintained. At the same time, the rear end face of the flange portion is brought into contact with the front end face of the spindle to be constrained, so that the spindle can be mounted in the tapered hole of the spindle. An object of the present invention is to provide a tool holder that can hold a tool holder with a large restraining force and can withstand high-speed rotation and low-speed heavy cutting.

[0005]

[Means for Solving the Problems]

 The invention of claim 1 is a tool holder detachably fitted to a tapered hole of a spindle of a machine tool having a tapered hole having a small outside diameter on a rear side, wherein the tool holder is provided on a front side of a shank provided on a rear side of the holder body. A large-diameter flange is provided, and an elastic member is interposed between the rear end of the flange and the front end of the tapered cone fitted to the shank. The outer peripheral surface of the tapered cone is formed at an angle equal to the inner peripheral surface of the tapered hole of the spindle, and the inner peripheral surface of the tapered cone and the outer peripheral surface of the shank portion are supported by a tool holder supported by a stopper member provided on the shank portion. A taper of 1/10 to 1/100, which is smaller than the angle of the outer peripheral surface of the tapered cone and has a smaller diameter on the rear side, is formed in at least a part of the front and rear direction. The shank portion and the taper cone are restrained in a locked state by a wedge effect by a retraction force of a retraction member engaged with the holder main body, and a lining force of an outer peripheral surface of the taper cone with respect to an inner peripheral surface of a taper hole of the spindle. By actuating, the restraint is performed while maintaining the retraction force, which is the instantaneous point of the retraction force, and the rear end face of the flange is abutted against the front end face of the spindle to be restrained. is there.

[0006]

[Embodiment of the invention]

 As shown in FIGS. 1 and 2, the tool holder 1 of the first embodiment has a shank portion 3 provided on the rear end side of the holder body 2 and a large outer diameter flange portion 4 provided on the front end side of the shank portion 3. A front end 6 is formed on the front end side of the flange 4 in series.

A rear end surface 4 a of the flange portion 4 is formed at right angles to the axial direction from the outer peripheral side toward the center side, and an arm (not shown) of an automatic tool changing device is engaged with the outer peripheral surface of the flange portion 4. A trapezoidal groove 4b is formed so as to engage as much as possible, an annular concave portion 4c is formed in the rear end surface 4a of the flange portion 4, and an elastic member 7 described later is fitted in the annular concave portion 4c. 4e, 4e are key grooves.

A front end surface of the shank portion 3 abuts against an elastic member 7 so that a taper cone 8 constituting a taper shank is slidably fitted in a radial direction and an axial direction, and a rear end of the taper cone 8 is provided. A stopper member 9 for adjusting a preload, which will be described later, is fitted to the shank portion 3, and a pull stud 10 for supporting the rear end surface of the stopper member 9 is screwed and fixed to the rear end portion of the shank portion 3. The taper cone 8 is pressed against the elastic member 7 through the, and the elastic member 7 is compressed to apply a preload.

As shown in FIG. 3, the diameter of the tapered cone 8 decreases from the front side to the rear side, and the entire outer peripheral surface is formed to have a taper α of 1/10 taper. The entirety is formed to have a taper β smaller than the outer peripheral surface such as a 1/50 taper.

As shown in FIGS. 3 and 4, the taper cone 8 is provided with a slit 8a having a gentle inclination with respect to the axial direction and separated from the entire length at one location in the circumferential direction. An elastic body 8b such as rubber is filled so as to be elastically deformable in the radial direction. The elastic body 8b is filled with the slit 8a so as not to protrude from the inner and outer peripheral surfaces of the tapered cone 8, and is fixed to an opposing surface of the slit 8a with an adhesive so as to have a dustproof function. I have.

The elastic member 7 is formed by stacking a plurality of annular disc springs 7a made of an elastic metal plate such as a steel plate and a thin plate 7b made of an annular metal plate. It is housed in the recess 4 c and is interposed between the bottom of the recess 4 c and the front end face of the tapered cone 8. The stopper member 9 is configured such that an elastic ring 9a and a washer 9b are overlapped, and these are supported on the rear end face of the tapered cone 8 by a large-diameter support portion 10b of a pull stud 10.

Further, on the outer peripheral surface of the portion of the shank portion 3 where the tapered cone 8 is fitted, a lubricant enclosing groove 3 a is formed in a mountain shape that is continuous in the circumferential direction, and a lubricant such as grease is filled in the enclosing groove 3. The relative movement between the shank 3 and the tapered cone 8 can be smoothly performed over a long period of time.

A tapered hole 11 for holding a collet and a straight hole 12 extending to the rear end side of the tapered hole 11 are formed between the axially intermediate portion and the front end of the holder body 2, and the rear end of the straight hole 12 is formed. A bolt support portion 14 having a small-diameter bolt insertion hole 13 formed on the side thereof is annularly protruded toward the center side, and a rear end hole 15 is formed at the rear end side of the bolt insertion hole 13 and opens to the rear end surface of the holder body 2. Then, a female thread portion 15a is formed at an appropriate position in the axial direction of the rear end hole 15, and the holes 11, 12, 13, and 15 are provided in series in a manner concentric with the axis of the holder body 2.

The pull stud 10 tightens the front end male thread portion 10 a into the female thread portion 15 a of the rear end hole 15, and makes the large-diameter support portion 10 b abut on the rear end surface of the shank portion 3. An engaging portion 10c protrudes from the rear end side of 10b, a through hole 10d is formed in the center, and a flat notch 10e opposed to the large diameter supporting portion 10b is formed. Reference numeral 10f denotes a seal member fitted and disposed above the front end male thread portion 10a.

The tapered hole 11 and the straight hole 12 of the holder body 2 are fitted with a tapered portion 16 a on the front end side and a straight rear end portion 16 b formed in a series on the tapered collet 16. In the tapered portion 16a of the tapered collet 16, a taper equal to the tapered hole 11 is formed on the outer peripheral surface, and cut portions 16c are formed at three positions in the circumferential direction at equal intervals, and a circumferential central portion between the cut portions 16c is formed. A cutting fluid supply groove 16d is formed on the inner peripheral surface of each of the tapered collets 16, and a female screw hole 16e is formed in the rear end 16b of the tapered collet 16 so as to penetrate the center. The cut portion 16c is formed over the entire length of the tapered portion 16a, and the cutting fluid supply groove 16d is formed to be elongated from the front end to the rear end 16b of the tapered collet 16.

A pull bolt 17 is inserted from the rear end of the holder body 2 into the rear end hole 15, and the leg 17 a of the pull bolt 17 is inserted into the bolt insertion hole 13 from the rear end to form the leg 17 a. The collet 16 is screwed into a screw hole 16e to be formed at the rear end 16b of the collet 16 in the male screw portion 17b. The pulling bolt 17 has an engaging recess 17d having a regular hexagonal cross section in the head 17c, and a small-diameter cutting fluid passage hole 17e extending from the bottom of the engaging recess 17d to the tip of the leg 17a. It is formed so as to penetrate the shaft center. The head 17c is supported on the rear end face of the bolt support portion 14 of the holder body 2 via a washer 18 fitted to the leg portion 17a. Reference numeral 19 denotes a tool such as an end mill or a drill in which a shank 19a is fitted to the taper collet 16.

In FIG. 2, reference numeral 20 denotes a spindle of a machine tool. A tapered hole 21 is formed at the front end of the spindle 20. The tapered hole 21 opens at the front end of the spindle 20, and The inner peripheral surface 21a is formed in a 1/10 taper having a small diameter on the rear end side. A retracting member 22 is provided on the rear end side of the tapered hole 21 of the spindle 20. Further, metal members such as the holder body 2, the taper cone 8, the taper collet 16 and the like are subjected to rust prevention treatment so that rust does not occur on the metal members due to cutting fluid or the like.

To use the tool holder 1 of the first embodiment configured as described above, the arm of the automatic tool changer is engaged with the trapezoidal groove 4 b provided on the flange portion 4 of the tool holder 1. The flange 4 is gripped, and the engaging portion 10c of the pull stud 10 provided on the tool holder 1 is engaged with the front end of the retracting member 22 provided in the spindle 20 of the machine tool. The outer peripheral surface of the tapered cone 8 of the tool holder 1 is brought into close contact with the inner peripheral surface of the spindle 20 by being pulled backward. When the pull stud 10 is pulled into the rear side of the spindle 20, the shank portion 3 of the holder body 2 fixed to the pull stud 10 and the taper cone 8 fitted in the shank portion 3 are pulled rearward, and the outer periphery of the shank portion 3 The tapered cone 8 is drawn into the tapered cone 8 by pulling in the shank 3 because the surface and the inner peripheral surface of the tapered cone 8 are formed with a taper such as 1/50 taper which is equal to each other and whose rear side has a small diameter. As shown by K, the wedge effect works and the inner peripheral surface of the tapered cone expands, and the lining force acts as shown by the arrow N.

Further, the inner peripheral surface 21 a of the tapered hole 21 of the spindle 20 and the outer peripheral surface of the tapered cone 8 are formed with a taper having a smaller diameter on the rear side of the same 1/10 taper. The tightening force M of the inner peripheral surface 21a of the taper hole 21 acts to reduce the diameter of the taper cone 8, but the inner tension force as shown by the arrow N of the taper cone 8 acts to strongly restrain both. This is possible even if the retraction force of the tool holder 1 is relatively weak. It is already known that the smaller the taper angle, the higher the coupling rigidity.

FIG. 6 is an explanatory view showing the state of the pulling force when the holder body 2 is drawn into the tapered hole 21 of the spindle 20 by a draw bar in the tool holder 1 of the present invention and the conventional standard type tool holder. . For example, when the set value of the retraction force of the holder main body 2 is set to 900 kg, when the tool holder 1 is mounted in the tapered hole 21 of the spindle 20, the retraction member 22 connected to the draw bar (not shown) is retracted. The instantaneous retraction force of the disposed coned disc spring (not shown) or the like is called a hammering effect, and varies depending on the retraction force set value and the retraction speed. It reaches a pulling force of about 1,200 kg, which is 0.8 times.

However, in the conventional standard type tool holder, since the inner peripheral surface of the taper cone and the outer peripheral surface of the shank portion are respectively straight in the front-rear direction, the retracting force of 900 kg which is the retracting force set value indicated by the dotted line is immediately obtained. Return and the cutting work is performed in this state.

On the other hand, according to the tool holder 1 of the present invention, when the draw bar pulls the pull stud 10 to the rear side of the spindle 20 when the tool holder 1 is mounted in the tapered hole 21 of the spindle 20, the pull The shank portion 3 of the holder main body 2 fixed to the stud 10 and the tapered cone 8 fitted to the shank portion 3 are retracted rearward, and the outer peripheral surface of the shank portion 3 and the inner peripheral surface of the tapered cone 8 are equal to each other. Since the taper or the like is formed with a loose taper having a small diameter on the rear side, the outer peripheral surface of the shank 3 is restrained by the retraction of the shank 3 against the taper cone 8 in a locked state by a so-called wedge effect. As a result of the lining force of the outer peripheral surface of the taper cone 8 acting on the inner peripheral surface 21a of the tapered hole 21, the instantaneous point of the retraction force is obtained. The restraint can be performed while maintaining a certain 1200 kg retraction force. Therefore, the tool holder 1 attached to the tapered hole 21a of the spindle 20 can be closely held with a large restraining force, and the tool holder 1 that can withstand high-speed rotation and low-speed heavy cutting can be provided.

The fact that the restraint can be performed while maintaining the retraction force, which is the instantaneous end point of the retraction force, is a problem when applied to a retraction means of a spindle used for 4 to 5 years in which the retraction force decreases. Of course, the effect of improving the pulling force can be exerted. The automatic tool changer removes the arm from the trapezoidal groove 4b in a timely manner and returns the arm to the position before the operation.

After performing the above-described processing, in order to perform automatic tool change of the tool holder 1, the arm of the automatic tool changer is engaged with the trapezoidal groove 4 b to grip the flange 4, and the tip of the spindle 20 is rotated. Pull out the tool holder 1 to the side.

The tapered cone 8 provided in the tool holder 1 of the first embodiment is a pull-down type in which the rear end surface of the tapered cone 8 fitted to the shank portion 3 of the holder main body 2 is screwed to the rear end portion of the shank portion 3. The large-diameter support portion 10b of the stud 10 is brought into contact with the rear end surface of the shank portion 3 and pushed toward the front end side, and the elastic member 7 is fitted into the annular concave portion 4b formed on the rear end surface 4a of the flange portion 4; Since the front end face is pressed against the flange portion 4 via the elastic member 7, the taper cone 8 can be moved in the axial direction of the shank portion 3, and the taper cone 8 is provided with a notch 8a over the entire length in the circumferential direction. Since the elastic body 8b is filled in the notch 8a and the slit 8a is filled with the elastic body 8b, the diameter of the taper cone 8 can be expanded and reduced. In addition, the rear end face 4a of the flange portion 4 can be securely brought into close contact with the front end face 20a of the spindle 20 and restrained.

In the first embodiment, in order to replace a tool 19 whose blade part has been worn or missing due to use, the tool holder 1 is detached from the machine tool, carried to a tool changing work place, and the flange part of the holder body 2 is replaced. 4 is fixed to a vise table by a vise or the like, and the front end of the cross-section regular hexagonal operation rod bent in an L shape from the rear end side of the pull stud 10 is inserted into the through hole 10 d of the pull stud 10. Into the engaging recess 17d provided in the head 17c of the pull bolt 17.

Then, the operation rod is rotated outside the pull stud 10 in the loosening direction, and the pull bolt 17 is rotated in the same direction, so that the head 17c abuts on the front end of the pull stud 10 and is further loosened. By rotating in the female direction, the collet 16 is pushed toward the front end side of the holder main body 2 by screw fitting between the external thread 17b of the pull bolt 17 and the female screw hole 16e of the taper collet 16, and the collet 16 Loosen the tightening by the tapered hole 11 at the front end of the holder body 2.

As a result, the tightening of the shank 19 a of the tool 19 by the tapered portion 16 a of the collet 16 is also loosened, so that the tool 19 is pulled out from the collet 16 and the shank 19 a of the usable tool 19 such as a new tool is changed to the taper of the collet 16. It can fit into the part 16a. Thereafter, the operation rod is used to rotate the pull bolt 17 in the tightening direction and pull the tapered portion 16a of the collet 16 into the tapered hole of the holder body 2 in the tightening direction. 11, the tool shank is held and fixed to the front end of the holder main body 2 via the collet 16, and then the operating rod is pulled out to the rear end side of the tool holder 1, and the flange portion 4 is removed. By removing it from the force, the tool holder 1 can be reused.

Further, the tool holder 1 is mounted on the spindle 20, the tool 19 is advanced while rotating the spindle 20, and a cutting fluid is supplied from the center of the spindle 20 when machining the workpiece. The cutting fluid is passed through the through hole 10 d of the pull stud 10, the rear end hole 15 of the holder body 2, the engaging recess 17 d of the pull bolt 17, and the rear end 16 b of the tapered collet 16, and the cutting fluid supply groove of the collet 16 is formed. Through the front end of the collet 16 through 16d, the jet is ejected along the outer peripheral surface of the tool 19 to cool the blade portion of the tool 19 and the machined portion of the workpiece by the blade portion.

In the invention of the first embodiment, the flange portion is formed integrally with the holder main body, or the whole or a part other than the front end portion is formed as a separate member, and this member is fitted to the outer periphery of the holder main body by shrink fitting or the like. It is configured by fixing. Further, in the invention of the first embodiment, the inner peripheral surface of the tapered hole provided at the front end of the spindle and the outer peripheral surface of the tapered cone are each formed into a tight taper such as a 7/24 taper having a small diameter on the rear side. The inner peripheral surface and the outer peripheral surface of the shank portion of the holder main body can be formed by adopting a taper of 1/10 to 1/100 with a small diameter on the rear side, and a loose taper such as 1/50 is preferable. .

As shown in FIG. 7, the tool holder 1 of the second embodiment is provided with a shank 3 at the rear end of the holder body 2 and a large-diameter flange 4 at the front end of the shank 3. is there . An annular concave portion 4c is formed in the rear end surface 4a of the flange portion 4, an elastic member 7 is fitted in the annular concave portion 4c, and a tapered cone 8 is rotatably fitted on the outer periphery of the shank portion 3; The portion is provided with a stopper member 9 for preload adjustment.

The tapered cone 8 is formed such that the entire outer peripheral surface is formed into a tight taper of 7/24 taper, and the front side 8 g of the inner peripheral surface is formed to have a taper of 1/10 to 1/100, preferably 1/50. The intermediate portion 8h connected to the front side portion 8g is slightly protruded toward the center through a step, and a straight portion 8i is formed after the intermediate portion 8h.

The shank portion 3 is formed such that the front side 3c of the outer peripheral surface is formed into a 1/10 to 1/100 taper equal to the front side 8g of the tapered cone 8, preferably a 1/50 taper, and a loose taper. The intermediate portion 3d connected to the intermediate portion 3 has a slightly smaller outer diameter, a straight cylindrical straight portion 3e connected to the intermediate portion 3d, and a rear end portion 3f having an equal outer diameter connected to the rear straight portion 3e.

The tapered cone 8 is fitted to the shank 3, the front side 8 g of the tapered cone 8 is fitted to the front side 3 c of the shank 3, and the intermediate portion 8 h of the tapered cone 8 and the intermediate portion 3 d of the shank 3 are connected. A radial gap a and a longitudinal gap b are formed therebetween, and the straight portion 8i of the taper cone 8 is fitted to the straight portion 3f of the shank portion 3.

The stopper member 9 is fitted with a washer 9b on the rear end 3f of the shank portion 3 protruding from the rear end surface of the tapered cone 8, and a nut 9c is screwed onto the rear end 3f to be tightened. Is pressed against the rear end face of the tapered cone 8.

Further, on the outer peripheral surfaces of the front side portion 3c and the straight portion 3e of the shank portion 3, a lubricant enclosing groove 3a and a lubricant enclosing groove 3g are formed in a mountain shape continuous in the circumferential direction, respectively. The grooves 3a and 3g are filled with a lubricant such as grease. A tapered hole 21 is formed at the front end of the spindle 20 of the machine tool. The tapered hole 21 is opened at the front end face, and the inner peripheral surface 21a of the tapered hole 21 is formed with a 7/24 taper having a small diameter at the rear side. .

The configuration of the tool holder of the second embodiment other than that described above is the same as that of the tool holder of the first embodiment. The use and effect of the tool holder of the second embodiment are the same as those of the tool holder of the first embodiment, but the second embodiment is different from the tool holder of the first embodiment in that the front side 8g of the tapered cone 8 and the front side of the shank 3 are provided. 3c has a tapered fit, so that the length of the cutting process for the portion forming the taper is short, so that the process can be easily performed, and the straight portion 8i provided on the rear side of the tapered cone 8 and the shank portion. 3, the tapered cone 8 can be supported by the shank 3 at the front and rear two places, reducing vibration during use and improving the machining accuracy of the workpiece by the tool. Can be.

The tool holder of the second embodiment can use the tapered cone 8 of the modified example shown in FIG. 8, and the front cut 8 c and the rear cut 8 d are formed from the front end and the rear end of the tapered cone 8. The front notch 8c and the rear notch 8d are inclined at the same angle with respect to the axial direction, and the front and rear notches 8c and 8d are formed with a fluorine-based gap between the front and rear notches 8c and 8d. Elastic bodies 8e and 8f such as rubber are filled, respectively, and are fixed to the opposing surfaces of the slits 8c and 8d with an adhesive so as to have a dust-proof function. Of the elastic body 8e, 8f is slow aging and enables long-term use. The taper of the inner peripheral surface and the outer peripheral surface of the tapered cone 8 is the same as that of the taper cone shown in FIG.

As shown in FIG. 9, the tool holder 1 according to the third embodiment has two flat arc-shaped shim plates 24, 24 on the rear end face 4 a of the flange portion 4 of the holder main body 2, between both ends thereof. The holes 4a, 24a provided in the shim plates 24, 24 are fitted with countersunk screws 25, 25, respectively, and the female screw holes 4d, 4d formed in the flange portion 4 in advance are provided. The rear surfaces of the shim plates 24, 24 are in close contact with the front end surface 20a of the spindle 20 of the machine tool.

The configuration of the tool holder according to the third embodiment other than that described above is the same as that of the tool holder according to the second embodiment. The use and effect of the tool holder of the third embodiment are the same as those of the tool holder of the second embodiment. However, in the third embodiment, the shim is obtained by attaching and detaching the tool holder 1 to and from the spindle 20 many times. When the plates 24, 24 are damaged due to wear or the like, they are replaced with new ones. When the shim plates 24, 24 are not attached to the rear end face 4a of the flange 4 where the shim plates 24, 24 are not attached due to the multiple attachment / detachment of the tool holder 1, Alternatively, after the rear end of the flange portion 4 is cut, a shim plate having a required thickness may be supported on the rear end surface and fixed by flathead screws. It is preferable that a plurality of shims having different thicknesses are prepared, and a shim having an appropriate thickness is used.

The tool holder of each of the above embodiments is not limited to use mounted on a spindle of a vertical machine tool, and can be used even if mounted on a spindle of a horizontal machine tool. The taper cone of the tool holder of each of the above embodiments need not form a split.

[0042]

[Effect of the invention]

 As described above, the present invention relates to a tool holder removably fitted in a tapered hole of a spindle of a machine tool having a tapered hole having a small outer diameter on a rear side, and a shank provided on a rear side of the holder body. A flange part with a large outer diameter is provided on the front side of the part, and an elastic member is interposed between the rear end of the flange part and the front end of the tapered cone fitted to the shank part. An outer peripheral surface of the tapered cone is formed at an angle equal to an inner peripheral surface of a tapered hole of the spindle, and the inner peripheral surface of the tapered cone and the shank portion are formed in a tool holder in which a rear end surface of the tapered cone is supported by a stopper member provided on a shank portion. 1/10 to 1/100 taper, which is smaller than the angle of the outer peripheral surface of the tapered cone, is equal to the outer peripheral surface of the tapered cone. The shank portion and the tapered cone are restrained in a locked state by a wedge effect by a drawing force of a drawing member engaged with the holder main body, and the tapered hole with respect to an inner peripheral surface of a tapered hole of the spindle. By applying a lining force on the outer peripheral surface of the tapered cone to restrain the drawing force, which is an instantaneous point of the drawing force, while maintaining the drawing force, the rear end surface of the flange portion is brought into contact with the front end surface of the spindle. The holder body is retracted to the rear side by the retracting member provided in the spindle, thereby restricting the outer peripheral surface of the shank portion and the inner peripheral surface of the taper cone, and expanding the diameter of the taper cone. The outer peripheral surface is restrained by a lining force that presses the outer peripheral surface against the inner peripheral surface of the tapered hole of the spindle, and the rear end surface of the flange portion is fixed to the spindle. Due to the three-sided constraint of contact with the end surface, even if the pull-in force of the holder body is weak, the outer peripheral surface of the tapered cone is in close contact with the inner peripheral surface of the tapered hole, and the tapered cone is sufficiently restrained and strongly held With the tool attached to the tool holder by driving the spindle, it is possible to perform high-precision cutting with excellent damping effect and sufficient withstand high-speed rotation and low-speed heavy cutting. In addition, since the pulling force, which is the instantaneous point of the pulling force, can be restrained while maintaining the pulling force, the function of increasing the pulling member of the tool holder can be exhibited, and the pulling force is reduced. It is also suitable when applied to the means of pulling in the spindle used for a year.

[Brief description of the drawings]

FIG. 1 is an exploded side view showing a tool holder according to a first embodiment of the present invention.

FIG. 2 is an explanatory longitudinal sectional view of the tool holder shown in FIG. 1;

FIG. 3 is an enlarged vertical sectional view of a taper cone of the tool holder shown in FIG.

FIG. 4 is a front view of a taper cone of the tool holder shown in FIG. 1;

FIG. 5 is an operation explanatory view of the tool holder shown in FIG. 1;

FIG. 6 is an explanatory diagram showing an operating state of a drawing force in the tool holder of the present invention and a conventional standard type tool holder.

FIG. 7 is a longitudinal sectional view showing a tool holder according to a second embodiment of the present invention.

FIG. 8 is a front view of a taper cone of the tool holder shown in FIG. 7;

FIG. 9 is a longitudinal sectional view of a main part showing a tool holder according to a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tool holder 2 Holder main body 3 Shank part 3a Lubricant sealing groove 3c Front end of shank outer peripheral surface 3d Intermediate part 3e Straight part 3f Rear end 4 Flange 4a Rear end 4b Trapezoidal groove 4c Annular recess 4d Female screw hole 6 Front end Part 7 Elastic member 7a Disc spring 8 Taper cone 8a Split 8b Elastic body 8c Front split 8d Rear split 8e, 8f Elastic body 8g Front side 8h Intermediate part 8i Straight part 9 Stopper member 9a Elastic ring 9b Washer 10 Front pull stud 10 Pull stud Part 10b Large diameter support part 10c Engagement part 10d Through hole 10e Flat notch part 10f Seal member 11 Tapered hole 12 Straight hole 13 Bolt insertion hole 14 Bolt support part 15 Rear end hole 15a Female thread part 16 Taper collet 16a Front end side Tapered part 16b Rear end part 16c Slot 16d Cutting fluid supply groove 16e Female thread hole 17 Pull bolt 17a Leg 17b Male thread 17c Head 17d Engaging recess 17e Cutting fluid passage hole 18 Washer 19 Tool 19a Tool shank 20 Spindle 20a Front end face 21 Tapered hole 21a Inner peripheral surface of tapered hole 22 Retraction member 24, 24 Shim plate 25, 25 Countersunk screw

Claims (1)

[Utility model registration claims] 1. A tool holder detachably fitted in a tapered hole of a spindle of a machine tool having a tapered hole having a small outer diameter on a rear side, wherein a large outside is provided on a front side of a shank provided on a rear side of the holder body. An elastic member is interposed between the rear end of the flange part and the front end of the tapered cone fitted to the shank, and the rear end face of the tapered cone with a small outside diameter is provided. In the tool holder supported by the stopper member provided in the portion, the outer peripheral surface of the tapered cone is formed at an angle equal to the inner peripheral surface of the tapered hole of the spindle, and the rear side is formed between the inner peripheral surface of the tapered cone and the outer peripheral surface of the shank portion. 1 which is smaller than the angle of the outer peripheral surface of the tapered cone,
A / 10 to 1/100 taper is formed at least in part in the front-rear direction, and the shank portion and the taper cone are restrained in a locked state by a wedge effect by a retraction force of a retraction member engaged with the holder body, And by applying a lining force of the outer peripheral surface of the taper cone to the inner peripheral surface of the tapered hole of the spindle, while restraining while maintaining the retraction force, which is the instantaneous point of the retraction force,
A tool holder, wherein a rear end surface of the flange portion is brought into contact with a front end surface of the spindle so as to be restrained.