JPS6140405Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a tool for boring or similar cutting operations, and more specifically, the invention is a tool that can accurately adjust the position of the cutting edge provided at the tip of the spindle according to the amount of rotation of a graduated nut. The invention relates to a finely adjustable cutting tool.

As shown in Fig. 1, a conventional cutting tool of this type has a scale nut 2 engaged with a bearing surface formed at the tip of a bushing 1, and a spindle 3 (the cutting edge is shown in Fig. A plurality of coils are inserted tightly into the circular holding hole 5 of the bushing with the rear end 4 (not shown) as a cylindrical shaft, and between the seat plate 6 and the bushing, which are not rotatable relative to the bushing and are attached to the rear end of the spindle. As shown in FIG. 2, a cylindrical fitting part 8 is formed between the spindle 3 and the graduated nut 2 which is engaged with the bushing 1, and a cylindrical fitting part 8 is formed between the spindle rear end 4' and the bushing. It is known that the fitting portion 9 of 1 is a non-cylindrical fitting, and a disc spring 10 is further interposed between the seat plate 6 and the bushing 1.

However, in the former case, the spindle is supported in two places: the fitting surface 11 between the bushing and the nut, and the fitting surface 12 between the bushing and the spindle. In addition, since a coil spring is used, there is a disadvantage that the spring force in the circumferential direction varies, which promotes the fall of the spindle.

On the other hand, the latter cutting tool uses a disc spring, and the spindle is supported by the fitting surfaces 13' and 13'' of the bushing and the nut, the fitting part 8 of the nut and the spindle, and the fitting part 8 of the bushing and the spindle. Since this is done by part 9, the fall of the spindle is reduced compared to the former, but since there is a non-cylindrical fit, manufacturing is difficult and costs are high.

Therefore, the present applicant proposed a cutting tool that has high reliability in machining accuracy, is easy to manufacture, and is cost-effective.

This invention provides a finely adjustable cutting tool with further improved rotation prevention means.

The configuration of this invention will be explained below with reference to the attached FIGS. 3 to 5.

As shown in FIGS. 3 and 4, the cutting tool of this invention has a spindle 21 having a cutting edge 20 at the tip.
, a graduated nut 23 that is screwed together with a male thread 22 formed on its neck, and the nut 23 on the front surface.
A seat surface 24 for supporting the spindle 21, a cylindrical support portion 25 that tightly contacts and supports the outer periphery of the body of the spindle 21 slightly behind the seat surface 24, a bushing 27 with a cavity 26 provided behind it, and a bushing 27 for supporting the spindle 21. 2
Seat plate 2 connected to the rear end of 1 using bolts 28
9, a ring 30 interposed between the rear outer circumference of the spindle 21 and the inner circumference of the bushing cavity 26 in contact with the seat plate, and an end face 31 of the ring and the cavity 26.
A plurality of disc springs 32 which are interposed between and are compressed when the bolt 28 is tightened, the spindle 21 and the bushing 2
The spindle rotation preventing means 40 is provided at 7 and 7.

The ring 30 is arranged concentrically with the spindle 21, and its inner circumferential surface and outer circumferential surface are respectively the outer circumferential surface of the rear end of the spindle 21 and the bushing cavity 2.
It is in close contact with the inner peripheral surface of 6. In other words, when the spindle falls due to cutting resistance, assuming that there is a fulcrum at the outer periphery of the nut 23 and the fitting part A of the bushing, the spindle will be supported at a position that is 180 degrees out of phase with the fulcrum and further away from the fulcrum. Therefore, by closely interposing a ring between the spindle and the bushing at the rear end of the tool as shown in the figure, the fall of the spindle can be reduced compared to conventional tools, and rattling can also be reduced. Decrease.

As can be clearly seen in FIG. 5, the rotation preventing means 40 is provided with a radial protrusion 41 protruding from the outer periphery of the seat plate 29 and an axial protrusion 42 protruding from the front surface of the inner periphery of the seat plate 29. On the other hand, long grooves 43 and 44 corresponding to the respective projections are provided on the rear surface of the bushing 27 and the spindle 21, and the projections 41 and 42 are slidably locked in the respective long grooves.
The anti-rotation means configured in this manner can be cast, so it is easier to manufacture than the previously proposed one, and the thickness of the ring 30 can be made thinner, and the axial length of the tool can be reduced. That will make it shorter.

Note that the protrusions 41 and 42 and the long grooves 43 and 44 are
It is better to provide multiple protrusions as shown in the figure, and
1 and 42 are preferably rectangular and in surface contact with the corresponding long grooves. It is sufficient that the protrusion 41 protrudes radially from the outer periphery of the seat plate 29, but as shown in the figure, the protrusion 41 may be bent so that its tip protrudes toward the front side of the seat plate to widen the engagement surface with the long groove 44. Good too.

FIG. 6 shows a tool in which the nut 23 and the bushing 27 are fitted in a tapered manner, and in this case too, the detent means 40 having the same structure as described above is employed.

As explained above, in the tool of this invention, a ring concentric with the spindle axis is interposed between the outer periphery of the rear end of the spindle and the cavity of the bushing in close contact with both, so that the spindle does not fall or wobble as compared to conventional tools. Compared to that, the amount is reduced, making it possible to perform highly reliable cutting even under high-load cutting conditions.

In addition, by using a disc spring as the elastic body, the spring force is applied uniformly in the circumferential direction of the spindle, which prevents the spindle from gouging when not cutting and allows smooth adjustment of the position of the cutting edge. be exposed.

Furthermore, the spindle and the bushing are fitted in a cylindrical manner, and the rotation of the spindle is prevented by locking protrusions provided on the outer and inner peripheries of the seat plate into long grooves provided on the rear surfaces of the spindle and bushing in correspondence with each protrusion. This structure makes it easy to manufacture, reduces costs, and has excellent effects such as shortening the axial length of the tool, making it ideal as a cutting tool for use under severe conditions. .

[Brief explanation of the drawing]

1 and 2 are cross-sectional views showing the main parts of a conventional cutting tool, FIG. 3 is a front view showing an example of the cutting tool of this invention, and FIG. 5 is an exploded perspective view, and FIG. 6 is a sectional view showing another embodiment. 20...cutting blade, 21...spindle, 23...
Nut with scale, 24... Seat surface, 25... Support part,
26...Cavity, 27...Butsing, 29...Seat plate, 30...Ring, 32...Disc spring, 40...
Rotating means, 41, 42...Protrusion, 43, 44
...Long groove.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A spindle having a cutting edge at its tip, a nut with a scale threaded onto its neck, a seating surface for engaging the nut on the front, and a body of the spindle on the back. A bushing having a hole for inserting the thread into the bushing, and a seat plate connected to the rear end of the spindle, and a seat plate that is in contact with the front surface of the seat plate between the outer circumference of the rear part of the spindle and the inner circumference of the cavity of the bushing. A ring interposed in close contact with the bushing, an elastic body interposed between the ring and the end face of the bushing cavity to press the nut against the bushing seating surface, and a spindle rotation prevention means provided between the spindle and the bushing. , the rotation prevention means is provided with a radial protrusion protruding from the outer periphery of the seat plate and an axial protrusion protruding from the front surface of the inner circumference of the seat plate, while the bushing and the rear surface of the spindle are provided with a radial protrusion protruding from the outer periphery of the seat plate and an axial protrusion protruding from the front surface of the inner periphery of the seat plate; A fine adjustment cutting tool characterized by having corresponding long grooves to lock the two together. (2) The fine-adjustable cutting tool according to claim 1, wherein each of the protrusions is rectangular and is brought into surface contact with the respective locking long grooves.