JP2000218412A - Tool holder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tool holder, wherein the falling-off of an engaging member during assembling and the jumping-out of the same during disassembling are prevented, assembling/disassembling is easy and a structure is simple. SOLUTION: Engaging members 2 and 2 installed to be axially movable in an oblong hole 1a provided in a tool holder 1 and engaged with a bit groove to inhibit its pulling-out are displaced in the diameter direction of the tool holder 1 in their retreated positions, and the fit is loaded without operating a tool sleeve 5. A thin plate spring 4 is disposed in the outer periphery of the tool holder 1 in the retreated positions of the engaging members 2 and 2, and after the displacement of the engaging members 2 and 2 in the diameter direction, the engaging members 2 and 2 are engaged with the pit groove by the restoring force of the thin plate spring 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a tool holding device for an electric tool such as a hammer drill.

[0002]

2. Description of the Related Art In recent years, an engaging member which is installed in an elongated hole provided in a tool holder so as to be movable in the axial direction and engages with a groove of a bit so that the bit cannot be disengaged. A tool holding device which can be displaced in the radial direction and can mount a bit without operating a tool sleeve has been developed and widely used.

[0003] Regarding this type of tool holding device, Japanese Patent Publication No.
JP-A-43003 discloses a method in which a spring is disposed between a tool holder (that is, a coupling sleeve) and a tool sleeve (that is, a sliding sleeve) to move an engaging member (that is, a ball) in the axial direction of the tool holder. There has been disclosed a tool holding device configured to apply a biasing force acting to cause the engagement member to perform the urging force (hereinafter, referred to as “prior art 1”).

According to Prior Art 1, in an assembled state,
The engagement member held in the elongated hole projects inward from the inner peripheral surface of the tool holder. Therefore, when the bit is inserted from the tip of the tool holder into the tool holder, the rear end of the bit comes into contact with the engagement member. When the bit is pushed in from this state, the engaging member is displaced radially outward while moving toward the rear of the tool holder against the spring, so that the bit can be further pushed. ,as a result,
The engaging member comes into contact with the outer surface of the bit by the urging force of the spring. When pushing the bit is continued and the groove formed in the bit moves to a position corresponding to the engaging member, the engaging member is displaced inward in the radial direction of the tool holder by the biasing force of the spring. , Engage with the groove of the bit. Thus, the bit can be mounted on the tool holder without operating the tool sleeve.

Japanese Patent Application Laid-Open No. 9-70772 discloses that
Between the tool holder (ie, barrel) and the tool sleeve (ie, operation sleeve), a regulating sleeve for regulating the movement of the engaging member (ie, key) in the radial direction of the tool holder is provided in the axial direction of the tool holder. A tool holding device that is slidably disposed and provided with stopper means for restricting the sliding of the regulating sleeve is disclosed (hereinafter, referred to as a tool holding device).
"Prior art 2").

According to the prior art 2, the stopper means prevents the regulating sleeve from advancing when the bit is pulled out from the inner peripheral side of the tool holder, and when the bit is inserted into the inner peripheral side of the tool holder, the stopper means. To allow for forward movement. Therefore, when the bit is inserted from the tip of the tool holder into the tool holder, the stopper sleeve advances the biasing force of the spring by the stopper means, whereby the engaging member is displaced inward in the radial direction of the tool holder, Engage with the bit groove. As described above, also in the prior art 2, the bit can be mounted on the tool holder without operating the tool sleeve.

[0007]

However, in the prior art 1, there is a possibility that the engaging member may fall off unexpectedly when the tool holding device is assembled, or the engaging member may jump out due to the pressing of the spring when disassembling. Disassembly and assembly are complicated.

[0008] Also in the prior art 2, there is a possibility that the engaging member may fall off unexpectedly when assembling the tool holding device. Further, in Prior Art 2, due to the structure of the stopper means and the like,
The structure of the entire tool holding device is complicated, the disassembly and assembly are complicated, and an assembling error is likely to occur at the time of assembly.

SUMMARY OF THE INVENTION It is an object of the present invention to prevent the engaging member from falling off during assembly and to prevent the engaging member from jumping out during disassembly.
An object of the present invention is to provide a tool holding device that can be easily disassembled and assembled and has a simple structure.

[0010]

In order to achieve the above object, according to the present invention, a bit (1a) is provided movably in an axial direction in an elongated hole (1a) provided in a tool holder (1). The engaging members (2, 2) which engage with the groove (20a) of the tool holder (20) to prevent the tool holder (1) from being disengaged are displaced in the radial direction of the tool holder (1) at the retracted position. In the tool holding device to which the bit (20) can be attached without the operation of (2), the engagement member (2, 2) is pressed against the outer periphery of the tool holder (1) at the retracted position by the engagement member (2, 2). An elastic member (4) that expands in diameter is arranged, and after the engaging member (2, 2) is displaced in the radial direction, the engaging member (2, 2) is moved by the restoring force of the elastic member (4). It is characterized in that it engages with the groove (20a) of the bit (20).

According to a second aspect of the present invention, in the tool holding device of the first aspect, the elastic member (4) is a thin plate spring.

According to a third aspect of the present invention, in the tool holding device according to the second aspect, the thin plate spring (4) has an opening (4a) in an outer peripheral portion, and is provided around the opening (4a) in a circumferential direction. It is characterized in that it is stopped and its axial movement is restricted.

According to a fourth aspect of the present invention, there is provided an elongated hole (31a) provided in a tool holder (31) so as to be movable in an axial direction, and a groove (40a or 40) of a bit (40).
an engagement member (32) that engages with b) to prevent it from being removed
Is displaced in the radial direction of the tool holder (31) in the retracted position, so that the bit (40) can be mounted without operating the tool sleeve (35). The long hole (31
a) forming a groove (31d) intersecting with said groove (a);
By disposing an elastic member (34) whose diameter is increased by pressing the engaging member (32), the engaging member (32)
After the radial displacement, the engaging member (32) is engaged with the groove (40a or 40b) of the bit (40) by the restoring force of the elastic member (34).

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A tool holding device A according to a first embodiment of the present invention applied to a hammer drill will be described below with reference to FIGS. The tool holding device A includes a tool holder 1, engagement members 2 and 2, a sleeve collar 3, a thin plate spring 4 as an elastic member, and a tool sleeve 5.

The tool holder 1 is formed in a cylindrical shape as shown in FIG.
have. Near the center of the tool holder 1,
A pair of opposed long holes 1a, 1a are formed so as to extend in the longitudinal direction of the tool holder 1, and these long holes 1a, 1a communicate with the bit insertion hole 1c.

In each of the long holes 1a, the opening width on the inner peripheral surface side of the tool holder 1 is smaller than the diameter of a roller 2 as an engagement member described later in detail.
Of the roller 2 is slightly larger than the diameter of the roller 2. Therefore, the roller 2 can be inserted into the elongated hole 1a from above, but a part of the roller 2 inserted as described above is partially inserted into the bit insertion hole 1 of the tool holder 1.
c, and does not fall into the bit insertion hole 1c. Further, the opening length of each slot 1a is larger than the length of the roller 2, and for example, as shown in FIG.

On the inner peripheral surface of the tool holder 1 at a substantially central position, ridges 1b, 1b, 1b as a rotary driver are provided.
Are formed to extend in the axial direction. This ridge 1
b, 1b, 1b are receiving grooves 20b, 20b, 20b formed on the outer peripheral surface of the bit 20 so as to extend in the axial direction thereof.
Respectively.

In a region extending from a substantially intermediate position between the long holes 1a and 1a to a rear end thereof, a step portion 1d for installing a thin plate spring 4 to be described later is provided on the outer peripheral surface of the tool holder 1 in the circumferential direction of the tool holder 1. It is formed in a ring shape (see FIG. 1).

The rear end of the tool holder 1 is fitted inside the front end of the cylinder 6, and both are connected to the connecting pin 1.
They are interconnected via 1 and 11. In these connecting portions, a ring-shaped connecting pin retainer 12 is attached to the outer peripheral surface of the cylinder 6. Connecting pin retainer 1
Reference numeral 2 abuts on the upper ends of the connecting pins 11 to prevent the connecting pins 11 from coming off. The cylinder 6 of this connecting pin retainer 12
Is restricted by the C-shaped retaining ring 13.

The above-described cylinder 6 is disposed inside the barrel 7 via a bearing 15 so as to be rotatable in the circumferential direction. Inside the rear end side of the cylinder 6, a piston (not shown) and a striker 9 are arranged so as to be capable of reciprocating sliding so as to form an air chamber therebetween.

On the other hand, the power of an electric motor (not shown) built in a motor case (not shown) is transmitted to the cylinder 6 via a power transmission mechanism (not shown), and is transmitted in the circumferential direction. With the tool holder 1. At the same time, the power of the electric motor is also transmitted to the piston, and the piston is reciprocated in the axial direction, while the air chamber is used as an air spring. Exercise. As a result, tool holder 1
While rotating, the striker 9 moves elastically and intermittently in the axial direction in conjunction with the above movement of the striker 9.

As shown in FIG. 1, the rollers 2 and 2 as the engaging members are disposed in the elongated holes 1a and 1a of the tool holder 1, respectively. Each roller 2 is movable in the axial direction within the elongated hole 1 a and is displaceable in the radial direction of the tool holder 1.

The sleeve collar 3 has an inner diameter slightly larger than the outer diameter of the tool holder 1 and a length slightly shorter than the length of the roller 2, and a collar body 3a integrally formed at the tip thereof. And the flange 3b. This sleeve collar 3, as shown in FIG.
The tool holder 1 is fitted to the outside at a substantially central portion.

The thin plate spring 4 is provided with a step 1 d of the tool holder 1.
It is formed in a C-shaped cross section so as to have a circumference slightly shorter than the outer circumference in FIG. 1 and a width slightly shorter than the width of the step 1d (see FIGS. 3 and 5).
That is, the thin plate spring 4 is partially cut at its periphery and has an opening 4a there. This thin leaf spring 4 is shown in FIG.
As shown in (1), when a part of the rollers 2 and 2 in the long holes 1a and 1a protrudes from the outer peripheral surface of the tool holder 1, the rollers 2 and 2 are elastically deformed outward to expand the diameter. On the other hand, the thin plate spring 4
As shown in (1), when the rollers 2 and 2 are immersed in the long holes 1a and 1a, the diameter of the rollers 2 and 2 is reduced by being elastically deformed inward by the restoring force of the thin plate spring 4 and closely attached to the step 1d. In such a reduced diameter state, the step 1d regulates the movement of the thin leaf spring 4 in the axial direction. Of course, the outer diameter of the thin leaf spring 4 when the diameter is reduced is smaller than the inner diameter of the sleeve collar 3.

Further, a detent key 19 is provided on the step 1d of the tool holder 1. This detent key 1
9 is engaged with the opening 4 a of the thin plate spring 4,
The rotation of the thin plate spring 4 in the circumferential direction with respect to the tool holder 1 is restricted.

The flange 3b of the sleeve collar 3 described above
The compression coil spring 16 is disposed between the compression coil spring 16 and a spring seat 18 provided at the tip of the cylinder 6. Therefore, a biasing force acting on the sleeve collar 3 to move the sleeve collar 3 forward of the tool holder 1 is applied to the compression coil spring 16.
Given by

A tool sleeve 5 is mounted on the outer periphery of the tip of the tool holder 1 so as to be slidable in the axial direction.
The tool sleeve 5 has an abutment portion 5 a on the inside, which can abut on the flange 3 b of the sleeve collar 3. When the tool sleeve 5 is moved rearward together with the sleeve collar 3 against the compression coil spring 16, the contact portion 5a of the tool sleeve 5 is
The tool 2 is disposed at an interval from the outer peripheral surface of the tool holder 1 so as to allow the rollers 2 and 2 to be displaced radially outward.

A dust cap 17 is attached to the tip of the tool holder 1, thereby restricting the forward sliding limit position of the tool sleeve 5.

Further, a front cap 8 is screwed inside the tip of the barrel 7 to close a gap between the tool sleeve 5 and the tip of the barrel 7 when the tool sleeve 5 slides in the axial direction. This front cap 8 and cylinder 6
Is provided with an oil seal 10. Also,
A cushion rubber 14 is disposed between the rear end of the front cap 8 and the bearing 15.

Next, a method of using the tool holding device A will be described below. Before the bit 20 is mounted on the tool holding device A, the sleeve collar 3 is placed in a state of being moved forward by the action of the compression coil spring 16 as shown in FIG. At this time, roller 2,
2 is arranged inside the sleeve collar 3, and the rollers 2, 2
Is placed in a state of protruding into the bit insertion hole 1c of the tool holder 1.

When the rear end of the bit 20 is inserted into the bit insertion hole 1c, the rear end of the bit 20 contacts the rollers 2 and 2. Rollers 2 and 2 are sleeve collars 3 as described above.
And the rollers 2 and 2 are placed in a state where the rollers 2 and 2 cannot be displaced radially outward of the tool holder 1.
When the insertion of the bit 20 is continued, the rollers 2, 2 move rearward. When the rollers 2 and 2 move rearward of the sleeve collar 3, the rollers 2 and 2 are displaced radially outward of the tool holder 1 against the thin plate spring 4 (see FIGS. 2 and 3).

When the insertion of the bit 20 is further continued, the rollers 2, 2 are restored by the restoring force of the thin plate spring 4 to the tool holder 1.
Are displaced radially inward, and the grooves 20a, 20
a (see FIGS. 4 and 5). When such a bit 20 is inserted, the receiving groove 20b of the bit 20
20b, 20b, the ridges 1b, 1 of the tool holder 1
b, 1b. Therefore, the torque of the tool holder 1 is transmitted to the bit 20. Thus, the bit 20 is securely mounted on the tool holder 1 without operating the tool sleeve 5.

In such a mounted state, the bit 20
Is movable in the axial direction within the range of the grooves 20a, 20a. Therefore, the bit 20 is in the tool holder 1
While rotating together with the striker 9, the striker 9 moves resiliently and intermittently in the axial direction in conjunction with the movement of the striker 9, thereby enabling machining of the work material.

Here, when the bit 20 is separated from the work material,
The rollers 2, 2, which have been placed at arbitrary positions in the axial direction within the elongated holes 1a, 1a of the tool holder 1, are pushed forward by the rear portions of the grooves 20a, 20a of the bit 20, and as shown in FIG. , Move into the sleeve collar 3. In this state, the rollers 2, 2 cannot be displaced radially outward of the tool holder 1. Therefore, the removal of the bit 20 from the tool holder 1 is reliably prevented.

When the bit 20 is to be removed from the tool holder 1, the tool sleeve 5 is moved backward against the compression coil spring 16 as shown in FIG.
The bit 20 may be pulled forward. That is, when the tool sleeve 5 is moved rearward in this manner, the sleeve collar 3 also moves rearward, and the restriction on the displacement of the rollers 2 and 2 toward the radial outside of the tool holder 1 is released. Therefore, in this state, if the bit 20 is moved forward, the roller 2,
2 are displaced outwardly, and these and the groove 20a of the bit 20;
The engagement with the bit 20a is released, and the bit 20 can be removed.

Next, a tool holding device B according to a second embodiment of the present invention will be described with reference to FIG. Tool holding device B
Is the same as the tool holding device A according to the first embodiment described above, except that the sleeve collar 23 is formed symmetrically in the transverse section as shown in FIG. Therefore, the same components are denoted by the same reference numerals, and description thereof will be omitted.

Sleeve collar 2 in tool holding device B
Reference numeral 3 denotes a collar body 23a having an inner diameter slightly larger than the outer diameter of the tool holder 1 and a slightly shorter length than the length of the roller 2, and an outward flange 23b integrally formed at a central portion thereof. It is composed of

The method of using the tool holding device B is the same as the method of using the tool holding device A, and a description thereof will be omitted. According to the tool holding device B, the same effect as that of the tool holding device A can be obtained, and in addition, since the sleeve collar 23 is formed symmetrically in the transverse section, the assemblability is improved.

Next, a tool holding device C according to a third embodiment of the present invention will be described with reference to FIG. Tool holding device C
Is the same as the tool holding device B according to the above-described second embodiment except that the engaging member 22 has a different shape. Therefore, the same components are denoted by the same reference numerals,
The description is omitted.

The engaging members 2, 2 in the tool holding device B are configured as rollers, whereas the engaging members 22, 22 in the tool holding device C are each configured as a ball.

The method of using the tool holding device C is the same as the method of using the tool holding device A, and a description thereof will be omitted. According to the tool holding device C, the same effect as the effect of the tool holding device B according to the above-described second embodiment can be obtained, and in addition, since the engaging member 22 is configured as a ball, the tool holder 1 long hole 1a,
The length of the sleeve 1a and the length of the sleeve collar 23 can be reduced, and the entire device can be reduced in size.

Next, a tool holding device D according to a fourth embodiment of the present invention applied to an impact driver will be described with reference to FIGS. 10A, the tool holding device D includes a tool holder 31, balls 32, 32 as engaging members, a coil spring 34 as an elastic member, and a tool sleeve 35. , Does not have components corresponding to the sleeve collars 3 and 23 in the tool holding devices A, B and C described above.

The tool holder 31 has a bit insertion hole 31c having a hexagonal cross section inside the tip end thereof (FIG. 1).
0 (a) and FIG. 10 (b)). At a position near the tip of the tool holder 31, a pair of opposed long holes 31a, 31
are formed so as to extend in the length direction of the tool holder 31, and these long holes 31a, 31a communicate with the bit insertion holes 31c.

In each elongated hole 31a, the tool holder 31
Is smaller than the diameter of a ball 32 as an engagement member described later in detail, while the opening width of the tool holder 31 on the outer peripheral side is
Slightly larger than the diameter of Therefore, the ball 32 can be inserted into the elongated hole 31a from above.
It is placed so as to protrude into one bit insertion hole 31c, and does not fall into this bit insertion hole 31c. Also,
The opening length of each elongated hole 31a is larger than the diameter of the ball 32, and for example, corresponds to about 1.5 times the diameter of the ball 32 as shown in FIG.

Further, as can be best understood from FIG.
A groove 31d intersecting with 1a is formed over the entire circumference.
The groove 31d is for accommodating a coil spring 34 described later. When the coil spring 34 is accommodated in the groove 31d, the coil spring 34 abuts on the ball 32, and the groove 31d is positioned at a front position in the elongated hole 31a. It is configured to be held.

As shown in FIG. 10 (a), the balls 32, 32 as the engaging members are elongated holes 31 of the tool holder 31.
a, 31a. Each ball 32
Is movable in the longitudinal direction within the elongated hole 31a and is displaceable in the radial direction of the tool holder 31.

The coil spring 34 as an elastic member is formed by connecting both ends of a tension coil spring to each other to form a ring, and is housed in the groove 31 d of the tool holder 31. As described above, when the coil spring 34 is housed in the groove 31d, the coil spring 34 abuts on the ball 32, and elastically holds the ball 32 at a front position in the elongated hole 31a.

The tool sleeve 35 is attached to the tool holder 31
The tool holder 31 is axially slidably mounted on the outer periphery of the distal end of the tool holder 31 so as to cover the long holes 31a. The tool sleeve 35 has a ring-shaped space 35a on its inner peripheral surface capable of accommodating the coil spring 34, and a ball pressing portion 35b disposed adjacent to the front thereof (see FIG. 11). The rearward sliding limit position of the tool sleeve 35 is regulated by a rearward stopper ring 38 fitted to the outer peripheral surface of the tool holder 31, while the forward sliding limit position is determined by the tool. The front stopper ring 37 fitted to the outer peripheral surface of the holder 31 and the spring receiving seat 36 engaged with the front stopper ring 37 are regulated.
A compression coil spring 46 is arranged between the spring receiving seat 36 and the above-described ball pressing portion 35b, and urges the tool sleeve 35 rearward.

In a state where the tool sleeve 35 is located at the rearward sliding limit position as shown in FIG. 11, the ball 32 is elastically pressed against the front wall of the elongated hole 31a by the coil spring 34. Moreover, in this state, the ball pressing portion 35b of the tool sleeve 35 abuts on the ball 32, so that the ball 32 is kept in a state in which the ball 32 cannot be displaced outward.

The configuration of the impact driver other than the above-described tool holding device D is the same as the configuration of the conventional impact driver, and the description thereof will be omitted.

Next, a method of using the above-described tool holding device D will be described with reference to FIGS. First, when attaching the bit 40 to the tool holding device D, the bit 40 may be inserted into the bit insertion hole 31 c of the tool holder 31. The bit 40 shown in FIGS.
Are ring-shaped grooves 40a, 4
0b are respectively formed.

That is, the bit insertion hole 3 of the tool holder 31
When bit 40 is inserted into 1c, as shown in FIG.
The tip of the bit 40 contacts the ball 32. When the bit 40 is pushed in this state, as shown in FIG. 13, the ball 32 moves rearward while the diameter of the coil spring 34 expands, and comes into contact with the rear wall of the elongated hole 31a.

When the bit 40 is further pushed in, the coil spring 34 moves into the space 35a of the tool sleeve 35 while further expanding its diameter, as shown in FIG. Displaced toward the outside of the holder 31, which allows further insertion of the bit 40 into the bit insertion hole 31 c.

When the insertion of the bit 40 is further continued and the groove 40 a of the bit 40 reaches the position of the ball 32, the ball 32 is displaced inward by the elastic force of the coil spring 34, and the ball 32 is It engages with the groove 40a. As shown in FIG. 15, the ball 32 engaged with the groove 40a by the elastic force of the coil spring 34 as shown in FIG.
It comes into contact with the front wall of the long hole 31a. In such a state, since the ball 32 is in contact with the ball pressing portion 35b of the tool sleeve 35, the displacement of the ball 32 to the outside is restricted unless the tool sleeve 35 is operated. Therefore, the bit 40 can be attached very easily without operating the tool sleeve 35 in this way, and in the attached state, the bit 40
Is securely stopped.

On the other hand, when removing the bit 40 from the tool holding device D, the tool sleeve 35 is slid forward against the compression coil spring 46 as shown in FIG.
In this state, the bit 40 may be pulled out. That is, when the tool sleeve 35 is slid forward, the contact between the ball pressing portion 35b and the ball 32 is released, and the ball 32 is placed in a state in which the ball 32 can be displaced outward as the diameter of the coil spring 34 increases. I will In this state, if the bit 40 is pulled out, the ball 32 is displaced outward while the coil spring 34 expands in diameter, and the engagement between the groove 40a of the bit 40 and the ball 32 is released. Bit insertion hole 31
Easy to remove from c.

In the above-described fourth embodiment, the coil spring 34 has been described as being formed in a ring shape by connecting both ends of a tension coil spring to each other. As long as it has an energizing action, its form is arbitrary. For example, it is formed by molding a resilient metal single wire into a C shape, or formed into a ring shape from an elastic synthetic resin or the like. A thing etc. may be used.

[0057]

According to the first aspect of the present invention, an elastic member whose diameter is increased by pressing the engaging member is arranged on the outer periphery of the tool holder at the retracted position of the engaging member, and the engaging member is displaced in the radial direction. After that, since the engagement member is configured to engage with the groove of the bit by the restoring force of the elastic member, it is possible to prevent the engagement member from dropping out at the time of assembly and popping out of the engagement member at the time of disassembly, A tool holding device which is easy to disassemble and assemble and has a simple structure can be obtained.

In the tool holding device according to the first aspect, if the elastic member is formed of a thin plate spring, the space for disposing the elastic member on the outer periphery of the tool holder can be small, and the tool can be used. The holding device can be made compact.

According to a second aspect of the present invention, as described in the third aspect, the thin plate spring has an opening in the outer peripheral portion, the opening is provided with a detent in the circumferential direction, and the shaft thereof is fixed. By configuring so that the movement in the direction is restricted,
The rotation of the thin plate spring in the circumferential direction of the tool holder is avoided, and the mounting and removal of the bit by the engagement member can be reliably performed.

According to the present invention, a groove is formed on the outer periphery of the tool holder so as to intersect with the long hole for the engaging member, and the elastic member is expanded in this groove by pressing the engaging member. Is arranged so that the engaging member is engaged with the groove of the bit by the restoring force of the elastic member after the engaging member is displaced in the radial direction. In addition, it is possible to obtain a tool holding device that prevents the engagement member from flying out during disassembly, facilitates disassembly and assembly, and has a remarkably simple structure.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a state before a bit is mounted on a tool holding device according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a state in which an engaging member is displaced by insertion of a bit in the tool holding device of FIG. 1;

FIG. 3 is a cross-sectional view showing a state in which the engaging member is displaced by insertion of the bit in the tool holding device of FIG. 1;

FIG. 4 is a longitudinal sectional view showing a state in which an engaging member is engaged with the groove after the bit is inserted in the tool holding device of FIG. 1;

FIG. 5 is a cross-sectional view showing a state in which the engaging member is engaged with the groove after the bit is inserted in the tool holding device of FIG. 1;

FIG. 6 is a longitudinal sectional view showing a state in which the mounted bit is separated from a work material in the tool holding device of FIG. 1;

FIG. 7 is a longitudinal sectional view showing a state in which the tool sleeve is moved backward to remove the bit in the tool holding device of FIG. 1;

FIG. 8 is a longitudinal sectional view showing a state before a bit is mounted on a tool holding device according to a second embodiment of the present invention.

FIG. 9 is a longitudinal sectional view showing a state before a bit is mounted on a tool holding device according to a third embodiment of the present invention.

FIG. 10 is a view showing a tool holding device according to a fourth embodiment of the present invention.

11 is an enlarged longitudinal sectional view of a main part of the tool holding device of FIG. 10;

FIG. 12 is a longitudinal sectional view showing a starting state of a bit mounting operation to the tool holding device of FIG. 10;

FIG. 13 is a longitudinal sectional view showing a state in which the ball is moved rearward by the bit in the operation of mounting the bit on the tool holding device of FIG. 10;

FIG. 14 is a longitudinal sectional view showing a state in which the ball is displaced outward by the bit in the operation of mounting the bit on the tool holding device of FIG. 10;

FIG. 15 is a vertical cross-sectional view showing a state in which the mounting of the bit is completed in the mounting operation of the bit to the tool holding device of FIG.

FIG. 16 is a longitudinal sectional view showing an operation of removing a bit from the tool holding device of FIG. 10;

[Explanation of symbols]

 A Tool holding device according to the first embodiment of the present invention B Tool holding device according to the second embodiment of the present invention C Tool holding device according to the third embodiment of the present invention D Tool according to the fourth embodiment of the present invention Holding device 1, 31 Tool holder 1a, 31a Long hole 2, 32 Engaging member 3 Sleeve collar 4, 34 Elastic member 4a Opening 5, 35 Tool sleeve 20, 40 bit 20a, 40a, 40b Groove 31d Groove

Claims (4)

[Claims] 1. An engaging member, which is installed in an elongated hole provided in a tool holder so as to be movable in an axial direction and engages with a groove of a bit to prevent the bit from coming off, a retractable position of the tool holder. Displaced in the radial direction, in a tool holding device capable of mounting the bit without operating the tool sleeve,
An elastic member that expands in diameter by pressing the engaging member is disposed on the outer periphery of the tool holder at the retracted position of the engaging member, and after the engaging member is displaced in the radial direction, the engaging force is restored by the restoring force of the elastic member. A tool holding device, wherein a member engages a groove of the bit. 2. The tool holding device according to claim 1, wherein the elastic member is a thin plate spring. 3. The thin plate spring has an opening in an outer peripheral portion,
The opening is provided with a circumferential detent, and
The tool holding device according to claim 2, wherein the movement in the axial direction is restricted. 4. An engagement member, which is installed in an elongated hole provided in the tool holder so as to be movable in the axial direction, and engages with a groove of a bit to prevent the bit from coming off, is provided at a retracted position of the tool holder. Displaced in the radial direction, in a tool holding device capable of mounting the bit without operating the tool sleeve,
By forming a groove that intersects with the long hole on the outer periphery of the tool holder, and disposing an elastic member that expands in diameter by pressing the engagement member in the groove, the engagement member is displaced in the radial direction. A tool holding device, wherein the engaging member engages with the groove of the bit by a restoring force of an elastic member.