JPH1177433A - Tap holding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily replace taps by forming a tap holder in which a short cylinder part for preventing rattle is integratedly provided in a row on a male fitting part, a male screw is screwed to a drive shank of an automatic screw hole cutting machine, a short cylinder part provided with a recessed groove is covered with a circular hole, and a through hole continuously connected to a short cylinder part for preventing rattle is provided. SOLUTION: A short cylinder part 3 provided with a recessed groove 3a to which a slip-out preventing screw 2 is pressure connected on the circumferential face is continuously connected to a top cutting edge part 1a, and a male fitting part 4 and a tap 1 continuously connected to a short cylinder part 5 are formed. A tap holder 7 is provided with a circular hole covering the short cylinder part 3, a female fitting part covering a male fitting part 4, and a screw hole 10 into which a slip-out preventing screw 2 is threadely inserted so as to communicate to the circular hole. A blind hole to be fitted with the short cylinder part 5 is provided continuing to the female fitting part is provided, a through hole 12 communicating to the blind hole is provided, and hence the tap holder 7 is formed. Hereby, the tap holder 7 can be fitted and detached quickly and easily against the tap.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tap holding device mounted on an automatic screw hole cutting machine.

[0002]

2. Description of the Related Art In a conventional automatic screw hole cutting machine, a tap holder and a tap mounted on a shank for transmitting a rotational force to the tap are detachably joined to each other by screwing, and tap exchange is performed.

A device according to Japanese Utility Model Publication No. 3-29068 is to attach a tap to a main shaft of a machine tool and process a female screw into a tap lower hole provided in a work, and to insert a tap into a tap holding shaft. At the bottom side of the hole, the end square part of the tap handle is fitted, and a square hole that transmits the rotational force is connected to this, and the sleeve into which the tip shaft part of the tap handle fits is inserted into the tap fitting hole. In the fitted and held tap holder, the square portion of the tap handle portion is loosely fitted into the tap insertion hole of the tap holding shaft, and the stopper abutting on the step formed at the boundary between the square portion and the shaft portion is provided. The stopper is supported at the bottom of the tap fitting hole, and when the tip of the tap is pressed against the prepared hole of the work and bites, the bottom of the tap fitting hole and the step of the tap handle are connected. Tap replacement without causing scratches such as return due to bite Sometimes it is easy to pull out the tap holder.

[0004]

In an automatic screw hole cutting machine, a large cutting torque is applied to the tap by the screw cutting process, so that it is very difficult to release the screw between the tap and the tap holder when replacing the tap. Have difficulty.

The tap holder invented in accordance with Japanese Utility Model Publication No. 3-29068 is a hand-held type, and the screw is rotated while the tap is rotated in the reverse direction after forward rotation (forward rotation) by the main shaft of the machine tool during screw cutting. It is not a type in which a nut (work) having a female screw cut out from a shank (there is a straight type and an elbow type) and slides down like an automatic screw hole cutter.

[0006]

Means for Solving the Problems A short tube portion provided with a concave groove for press-fitting a retaining screw at a base end of a cutting edge portion, and a rectangular column-shaped male stopper for rotation prevention at a base end of the short tube portion. A tap in which a mating portion, a short tube portion for preventing looseness is integrally provided at the base end of the male fitting portion, and a male screw that is screwed to the distal end portion of the drive shank of the automatic screw hole cutting machine is provided with one end. And the other end is fitted with a circular hole that covers the short cylinder portion provided with the concave groove from the other end, a square-shaped female fitting portion that covers the male fitting portion, and the short cylinder portion for preventing backlash. By forming a tap holder provided with a blind hole and a through hole communicating with the short tube portion for preventing the backlash, the tap can be easily replaced after screw cutting and the tap can be secured in the tap holder. It is intended to provide a device.

[0007]

1 is a front view showing a tap 1 according to the present invention, and FIG. 2 is a right side view of the same. Reference numeral 1a denotes a blade edge, which is provided at its base end with a retaining screw 2 (FIG. 3).
A short cylindrical portion 3 provided with a concave groove 3a on the peripheral surface for pressing the cylindrical member 3 is provided continuously, and a male fitting portion 4 for preventing rotation in the form of a prism at the base end of the short cylindrical portion 3; The tap 1 is formed by integrally connecting the tubular portion 5 and the tubular portion 5.

FIG. 3 shows a drive shank 6 of an automatic screw hole cutting machine.
FIG. 4 is a partially cutaway front view showing a tap holder 7 provided at one end with a male screw 7a screwed into a female screw 6a provided at a tip end of the tap holder 7; A circular hole 8 covering the cylindrical portion 3 is bored in the axial direction, and a square-shaped female fitting portion 9 covering the male fitting portion 4 is integrally drilled. The screw hole 10 into which the screw 2 is inserted is connected to the circular hole 8 and is formed. The blind hole 1 into which the short cylinder portion 5 for preventing backlash is inserted following the female fitting portion 9
1 are integrally formed, and a through hole 12 communicating with the blind hole 11 is integrally formed to form the tap holder 7. Screw hole 10
Is formed with two holes in the diameter direction or four holes in the diagonal direction.
FIG. 4 is a left side view of the tap holder 7. FIG. 5 is a partially cutaway front view showing a state in which the tap 1 is joined to the tap holder 7 mounted on the shank 6 for transmitting the rotational force, and the tap 1 is set back in the blind hole 11 provided in the tap holder 7. The short cylindrical portion 5 is fitted into the female fitting portion 9 having a square hole shape.
And the short cylindrical portion 3 is inserted into the circular hole 8 to join the tap 1 to the tap holder 7 and to the screw hole 10 provided in the tap holder 7. The retaining screw 2 is screwed into the groove 3a provided in the short cylindrical portion 3 of the tap 1 so that the tap 1 does not come out of the tap holder 7 unnecessarily.

[0009]

Since the present invention is constructed as described above, the male fitting portion 4 and the female fitting portion 9 are not joined by screwing unlike conventional products, so that the taps mounted on the tap 1 and the shank 6 are used. The drawback that the attachment and detachment with the holder 7 is quick and easy, and it is difficult to release the screwing by applying a cutting torque to the tap 1 is surely eliminated. Since the tap 1 is pressed against the concave groove 3a of the screw insertion tap 1, there is no possibility that the tap 1 will be detached from the tap holder 7, and since the air flows through the through hole 12 provided in the tap holder 7, the tap 1 is moved to the tap holder 7. Can be easily removed from. Further, since the short cylindrical portion 5 provided on the tap 1 is in close contact with the blind hole 11 provided on the tap holder 7, the tap 1 does not rattle.

[Brief description of the drawings]

FIG. 1 is a front view showing a tap according to the present invention.

FIG. 2 is a right side view of the same.

FIG. 3 is a partially cutaway front view showing a state where the tap holder according to the present invention is mounted on a drive shank.

FIG. 4 is a left side view of the same.

FIG. 5 is a partially cutaway front view showing a state where a tap is fitted to and joined to a tap holder attached to a shank.

[Explanation of symbols]

1 ··· Tap 2 ··· Retaining screw 3 5 ··· Short tube part 3a ··· Groove 4 ··· Male fitting part 11 ··· Blind hole 6 ··· Shank 8 ··· Round hole 9 ··· Female type Fitting part 10 Screw hole 12 Hole

Claims (1)

[Claims] 1. A short cylinder portion having a groove formed around a base end of a cutting edge to press a retaining screw into pressure, a prism-shaped male detent for rotation prevention at a base end of the short cylinder portion, A tap in which a short cylinder portion for backlash is integrally connected to the base end of the male fitting portion, and a male screw screwed to a distal end portion of a drive shank of an automatic screw hole cutting machine are provided at one end, and A circular hole that covers the short tube portion provided with the concave groove, a square-shaped female fitting portion that covers the male fitting portion, and a blind hole into which the short tube portion for preventing backlash is integrally formed. And a tap holder provided with a through hole communicating with the blind hole.