JPH0585560U - Bit holder - Google Patents

Abstract

(57) [Abstract] [Purpose] To increase the holding power of the bit, improve the bit insertion / extraction operability and durability. [Structure] Bit holder hole 2 in the bit holder body 2
A pin fitting notched groove 15 having a part opening 14 on the inlet side inner peripheral surface is opened tangentially from the outer peripheral surface, and a bit locking pin 7 is provided in the notched groove 15 at both ends 7A thereof from the outer peripheral surface of the bit holder body 2. It has a tapered inner surface 18 that slightly protrudes and is fitted into the bit fitting hole 12 through the opening 14 of the cut groove 15 to press the pin 7 toward the axis of the bit holder body 2. The cylindrical cover 8
2 is fitted outside, and the bit lock holding spring 6 is fitted inside the cover 8 so that the cover 8 always presses the bit lock pin 7 and pushes the cover 8 in the axial direction to move the bit. Makes holding force releasable.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a bit holder for a rotary tool such as a manual or electric screwdriver and an air screwdriver.

[0002]

[Prior Art]

 Conventionally, as this kind of bit holder, the one exemplified in FIG. 8 is generally used. In this holder 21, a rotary tool mounting member 23 is provided on one end side in the axial direction of a cylindrical bit holder body 22, and a bit fitting hole 24 having a regular hexagonal cross section is provided on the other end side, and an inlet portion of the hole 24 is provided. A bit locking ring 26 (C-shaped snap ring, O-ring, etc.) is fitted, and a magnet 25 for wearing a screw magnet is fitted inside the hole 24, and the magnet 25 is fitted with a driver bit 27. Both tip head portions 28 (see FIG. 6) or the rear end flat portion 30 of the single-headed driver bit 29 shown in FIG. 7 come into contact with each other.

The driver bits 27, 29 are standardized, and the positions and sizes of the locking grooves 31, 32 are constant corresponding to the dimensions of the bits 27, 29.

[0004]

[Problems to be solved by the device]

 By the way, since the bit holder 21 in which the conventional bit locking ring 26 is fitted in the bit fitting hole 24 holds the bit by the resistance of the locking ring 26, the bit holding force is weak. 27 and 29 are easy to come off and there is a problem with durability, and the bit is not stable and it is difficult to use because it fluctuates due to the gap with the holder, but when replacing the bit, the protruding amount of the bit 27, 29 from the holder main body 22 Since there are few bits, there is a problem that it is difficult to pull out the bits 27 and 29 with your fingertips.

The present invention has been made in view of the above situation, and an object thereof is to provide a strong holding force for a bit and a fixed stopping method, and to perform a bit fitting / removing operation. To provide a bit holder that is easy and durable.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention takes the following technical means. That is, according to the present invention, in a bit holder in which a rotary tool mounting member is provided on one end side in the axial direction of the bit holder body and a bit fitting hole is provided on the other end side, the bit fitting hole inlet side of the holder body is provided. A pin fitting notch groove, which is partially open to the inner peripheral surface, is provided in the holder outer peripheral surface in the tangential direction thereof, and a bit locking pin is provided in the notch groove so that both ends thereof slightly project from the outer peripheral surface of the bit holder body. At the same time, a cylindrical cover with a tapered inner surface that fits into the bit fitting hole from the opening of the cut groove and presses the pin toward the axis of the bit holder body is used as a bit holder book. The present invention is characterized in that a bit locking holding spring is fitted on the body, and the cover is fitted in the cover to bias the bit locking pin so as to always press the bit locking pin toward the axis of the bit holder body.

[0007]

[Action]

 According to the present invention, the bit is inserted into the bit fitting hole of the bit holder while the cover is manually pushed against the elastic force of the bit locking holding spring to release the pressing force of the bit locking pin. When it is inserted and the pushing force of the cover is loosened, both ends of the bit locking pin are pressed by the tapered inner surface of the cover, and the bit locking pin is pressed toward the axis of the bit holder body to lock the bit. It is fitted into the groove and engaged and held.

In this way, when the bit locking pin is engaged with the bit locking groove, the bit locking pin is constantly urged by the spring through the cover and pressed against the bit locking groove, The bit is firmly held, so the bit is stable and stable. This state is maintained unless the cover is pushed against the spring. When pulling out the bit from the bit holder, you can easily pull out the bit from the bit holder body with the cover pushed by hand against the elastic force of the bit locking and holding spring. Bits can be exchanged by operation.

[0009]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show an embodiment of the present invention, in which a bit holder 1 includes a bit holder body 2, a rotary tool mounting member 3, a magnet 4, a bit support body 5, and a bit lock holding spring 6. , A bit locking pin 7, a cover 8, a spring seat 9 and a spring locking ring 10, and the outer end 3A of the rotary tool mounting member 3 is attached to a tool body (not shown) such as an electric screwdriver. It is fitted and fixed to the drive shaft, and the rotational force is transmitted to the bit holder body 2.

The bit holder body 2 is made of stainless steel and has a substantially tubular shape. A tool fitting hole 11 having a regular hexagonal cross section is provided on one end (right) side in the axial direction, and a bit fitting having a regular hexagonal cross section is provided on the other end side. An attachment hole 12 is provided, and a magnet fitting hole 13 having a circular cross section is provided in the center of the magnet 11 so as to communicate with the holes 11 and 12 at both ends. The bit support 5 is fitted in close contact with the hole 11) side and the front side with each other.

In addition, the holder main body 2 has an outer peripheral surface of the holder main body 2 such that an opening 14 is formed in a square shape at an inner peripheral surface of the bit fitting hole 12 near the front end, particularly at a hexagonal portion. A pin fitting notch groove 15 extending in the tangential direction is provided, and a ring engaging peripheral groove 16 is provided on the tool mounting hole 11 side of the groove 15. The rotary tool mounting member 3 is made of carbon tool steel and has a regular hexagonal cross section. One end of the rotary tool mounting member 3 is fitted and fixed in the tool mounting hole 11 of the bit holder main body 2, and the outer end 3A is attached to the tool main body. There is.

The magnet 4 is for holding a screw or a screw (not shown) magnetically attached to the tip head portions 28, 29A (see FIGS. 6 and 7) of the bits 27, 29, and has a cylindrical shape and Although it is shorter than the conventional example, since the rotary tool mounting member 3 that abuts the magnet 4 is made of carbon tool steel and the holder body 2 is made of stainless steel, the magnetic force is strong and there is no magnetic leakage. It has a sufficient magnetic force and is comparable to the conventional example.

The bit support 5 is a columnar body made of carbon tool steel and provided with a tapered hole 17 for bit support. The tapered hole 17 is provided so as to expand toward the bit inlet side (it may be a through hole). ), It is fitted in the magnet fitting hole 13 of the bit holder body 2. In addition, the taper hole 17 of the bit support 5 has the same taper as the taper surface 28A of the tip head portion 28 (see FIG. 6) of the double-headed driver bit 27, and supports the taper surface 28A of the bit 27, and the taper hole bottom The tip of the bit does not touch 17A. The rear end flat end surface 30 of the single-headed bit 29 (see FIG. 7) is brought into contact with and supported by the opening end surface 5A of the tapered hole 17 of the bit support 5.

The bit locking and holding spring 6 is a C-shaped spring wound around the outer circumference of the bit holder body 2 in a coil shape, and one end (left) side of which is externally fitted into the ring locking circumferential groove 16 of the body 2. It is locked by the locking ring 10, and the other end (right) side abuts the cover 8 via the spring seat 9. The cover 8 is always in the direction of the other end (right) side (arrow (a) in FIG. 1). Shown).

The locking pin 7 has a straight rod shape and its diameter is made slightly smaller than the width dimension of the cut groove 15, and both ends thereof substantially match the groove bottom ends of both end portions of the cut groove 15, and The bit holder body 2 is designed to slightly project from the outer peripheral surface of the bit holder body 2. The center portion of the pin 7 is inserted into the bit fitting hole 12 through the opening 14 at the bottom of the groove 15 of the bit holder body 2. The engaging grooves 31 and 32 of the bits 27 and 29 are fitted and engaged.

The cover 8 covers the spring 6, the locking pin 7, the spring seat 9 and the spring locking ring 10 and is fitted onto the outer periphery of the holder 2 so as to be slidable in the axial direction, and the front end 8A ( The bit insertion port side) is tapered and its tapered inner surface 18 is brought into contact with both ends 7A of the bit locking pin 7, and the bit locking pin 7 is moved in the direction shown by the arrow (c) in FIG. Always press and keep pressing unless cover 8 is moved in the direction indicated by arrow (b) in FIG.

Further, the outer peripheral central portion 8B of the cover 8 is knurled, and the rear end portion 8C (right end) is fitted onto the bit holder body 2 and then reduced in diameter by caulking to serve as a spring receiving portion. There is. The rear end caulking is performed after the bit locking pin 7, the spring locking ring 10, the spring 6 and the spring seat 9 are fitted into the cover 9, and the spring seat 9 is attached to the rear end. Supported by 8C.

Although the spring seat 9 can be omitted, even if the gap between the rear end 8C of the cover and the holder body 2 is not minimized by caulking, the end of the ridge 6 can be omitted. The spring 6 can be reliably supported without any part coming out. In the above embodiment, when the bits 27 and 29 are fitted into the bit holder 1, first, the cover 8 is manually pushed in the direction shown in the central portion (b) of FIG. Pushing against each other and releasing the 7A pressure on both ends of the bit locking pin 7, insert the bits 27 and 29 into the bit fitting hole 12 of the bit holder 1 and loosen the pushing force of the cover 8. The tapered inner surface 18 of the cover 8 presses both ends 7A of the bit locking pin 7 in the axial direction of the bit holder main body 2 (indicated by the arrow (c) in Fig. 1), and the center of the bit locking pin 7 is pushed. From the opening 14, the engaging grooves 31 and 32 of the bits 27 and 29 are fitted and engaged to be in a holding state.

In this way, when the bit locking pin 7 is engaged with the bit locking grooves 31 and 32, the bit locking pin 7 is always supported by the spring 6 via the cover 8 and its tapered inner surface 18. It is biased and pressed so as to bite into the bit locking grooves 31 and 32, and the bits 27 and 29 are firmly held and held, so that the bits 27 and 29 are stable and do not rattle. This state is maintained unless the cover 8 is pushed in the direction of the arrow (b) in FIG.

When removing the bits 27 and 29 from the bit holder 1 and replacing them, push the cover 8 in the direction shown by the arrow (b) in FIG. 1 to lock both ends of the locking pin by the tapered inner surface 18 of the cover 8. Since the pressing force of 7A is released, the bits 27 and 29 can be easily pulled out from the bit holder 1 by releasing the bits 27 and 29 at the same time as releasing them. By inserting it into the hole 12, it is possible to replace it very easily.

The present invention is not limited to the above-described embodiment. For example, the tapered inner surface 18 of the cover 8 may be expanded in the opposite direction, and the biasing direction of the bit lock holding spring 6 may be changed as shown in FIG. By making the direction of the middle arrow (b), it is possible to expect the same effect as that of the above-mentioned embodiment, and also to use it for a bit holder that does not have either one or both of the bit support 5 and the magnet 4. You can

[0022]

[Effect of the device]

 According to the present invention, as described above, in the bit holder in which the rotary tool attachment member is provided on one end side in the axial direction of the bit holder body and the bit attachment hole is provided on the other end side, the bit attachment of the holder body is performed. A pin-fitting notch groove, which is partially open at the hole inlet side inner peripheral surface, is opened tangentially to the holder outer peripheral surface, and a bit locking pin is provided in the notch groove at both ends of the bit holder main body outer peripheral surface. A tubular cover with a tapered inner surface that slightly protrudes from the cutout groove and is fitted into the bit fitting hole through the opening of the cut groove to press the pin toward the axis of the bit holder body. Is fitted onto the bit holder main body, and a bit lock holding spring for urging the cover to always press the bit lock pin toward the axis of the bit holder main body is fitted inside the cover. Features and This makes it easy to insert and remove the bit, and even if the amount of protrusion of the bit from the holder body is small, it can be easily pulled out, and the bit holding force is strong and can be fixed in a stable manner. Even if it bites into a hole such as a screw, the bit does not come off from the bit holder, and durability can be improved.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing an embodiment of the present invention.

FIG. 2 is a left side view of FIG.

FIG. 3 is a partially omitted plan view with a spring, a cover and the like removed.

FIG. 4 is a left side view of FIG.

FIG. 5 is a partially cutaway plan view of the cover.

FIG. 6 is a front view showing an example of a double-headed driver bit.

FIG. 7 is a front view showing an example of a single-headed driver bit.

FIG. 8 is a partially cutaway front view of a conventional example.

[Explanation of symbols]

 1 Bit holder 2 Bit holder body 3 Rotating tool mounting part 6 Bit locking holding spring 7 Bit locking pin 7A Both ends 8 Cover 12 Bit fitting hole 14 Opening 15 Pin fitting Notch groove 18 Tapered inner surface 27 Drill bit 29 Drill bit

Claims (1)

[Scope of utility model registration request] 1. A bit holder in which a rotary tool mounting member is provided on one end side in the axial direction of a bit holder body, and a bit fitting hole is provided on the other end side, in the bit fitting hole inlet side inner circumference of the holder body. A pin fitting notch groove, which is partially opened in the surface, is provided in the holder outer peripheral surface in the tangential direction thereof, and a bit locking pin is provided in the notch groove with both ends thereof slightly projecting from the outer peripheral surface of the bit holder main body A tubular cover with a tapered inner surface that fits into the bit fitting hole from the opening of the groove and presses the pin toward the axis of the bit holder body is fitted on the bit holder body. A bit holder holding spring for urging the cover so as to always press the bit locking pin toward the axis of the bit holder body is fitted in the cover. ..