JPH08267307A - Variable diameter type boring adapter - Google Patents

Abstract

PURPOSE: To provide a variable diameter type boting adapter that is ease of accuracy guarantee and less in lost motion. CONSTITUTION: An axial movement of a slide shaft 4 connected to a machine body is carried out with three bushes 10, 11 and 12 of a variable diameter means 9 and a slider 17 moving in the axial direct direction, thereby shifting a tool T in the radial direction, and thus any unbalance due to the movement of the tool T is compensated by a weight compensation means 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable diameter boring adapter.

[0002]

2. Description of the Related Art The applicant of the present invention has proposed a variable diameter automatic correction tool in Japanese Utility Model Laid-Open No. 3-65603.
This proposal corrects the wear of the tip by pushing up the tip by sliding the gradient contact piece on the polygonal gradient provided on the work rod, and is extremely effective as a compensation means. However, it is not easy to guarantee the processing accuracy of the polygonal line slope and the processing accuracy of the contact piece. Therefore, the backlash is likely to occur, the moment applied to the extruded tip is large, and the error is likely to occur in the displacement. There were drawbacks such as just coming out and not pulling in. In addition, Japanese Utility Model Application Laid-Open No. 3-65604 proposes a variable diameter type boring adapter. In this proposal, the tip is attached to the slider that engages with the upwardly inclined serration groove provided on the work rod, and the correction range of the tip wear amount is extremely effective as compared with the conventional method. However, the processing accuracy and play of the upwardly inclined serrations and the sliders that engage with the serrations have the same drawbacks as the previous proposal.

[0003]

With the conventional deformation means in boring cutting, it is not easy to guarantee the processing accuracy of the structure as described above, and backlash is likely to occur.

An object of the present invention is to provide a variable diameter type boring adapter which is easy to guarantee accuracy and has no play.

[0005]

According to the present invention, a slide wheel is engaged with an inner hole of a main shaft provided in a housing of a boring head via a helical spline, and is rotated by axial movement of the slide wheel. An inner spline shaft is provided, variable diameter means for moving the tool in the radial direction by rotation of the inner spline shaft is provided, and weight correction means connected to the variable diameter means is provided.

Further, the variable diameter means is provided with an eccentric shaft hole and a cylindrical inner bush having a pin at the shaft center, and an eccentric inner hole larger than the outer diameter of the inner bush, and slides the pin in the radial direction. An outer bush provided with a long hole that can be freely accommodated; a middle bush provided with an eccentric shaft hole that has an outer diameter that engages with the inner diameter of the outer bush and that houses the inner bush; a dovetail groove formed in the housing; The slider is slidably housed in the dovetail groove.

Further, the weight correcting means is slidably accommodated in the drive rack provided on the slider, the pinion engaged with the drive rack and provided on the housing, the guide channel formed in the housing, and the guide channel. It is composed of a drive piece that meshes with the pinion and a weight that is screwed into the drive piece.

[0008]

In the variable-diameter boring adapter configured as described above, the axial movement of the slide shaft by the machine body is caused by the helical spline passing through the inner spline shaft, the outer bush having the eccentric inner hole, and the outer bush. The eccentric shaft hole is provided, and the variable outer diameter is changed by combining the three bushes of the inner bush with the slider that slides the dovetail of the housing vertically. At this time, the unbalance weight due to the movement of the tool is corrected by the weight correction means.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, a variable-diameter boring adapter 1 is roughly composed of a boring head 2 designated by the general reference 2 which is coaxially arranged, a main shaft 3 and a slide shaft 4. In the cylindrical housing 6 of the boring head 2, a variable diameter means 9 and a weight correcting means 20, which are generally designated by reference numerals 9 and 20, are housed. The weight correction means 20 is composed of a pair of units 20A.

2 to 5, the main shaft 3 is
One end is connected to a machine body (not shown) by a bar (not shown), and the other end is fastened to the housing 6 of the boring head 2 by a plurality of bolts 8.

One end of the slide shaft 4 is connected to the machine body, and the slide shaft 4 is slidably housed in the inner hole of the main shaft 3 in the middle.
It is locked in the rotational direction by a key 5, and an outer helical spline 4a is formed on the housing 6 side.

The inner spline shaft 7 has an inner helical spline 7c that engages with the outer helical spline 4a on the inner circumference.
Is formed, and the outer periphery is rotatably engaged with the inner hole of the main shaft 3. Both sides of the outer peripheral flange portion 7a are supported by bearings 16 and 16, and the outer peripheral shoulder portion 7b is also supported.
Bearings 16 are supported in the radial direction.
Further, the outer bush 10 is bolted to the outer bush 10 by a plurality of bolt holes provided inside the flange portion 7a.

The variable diameter means 9 includes an inner bush 12 and
The outer bush 10, the middle bush 11 housed between the bushes 10 and 12, the dovetail groove 18 formed axially on the end surface of the housing 6, and the slider 17 engaged in the dovetail groove 18. It is composed of and.

The inner bush 12 has a cylindrical shape, and an eccentric shaft hole into which the tool T is fitted, that is, a tool shaft hole 13 is formed at a position eccentric from the shaft center C, and the side opposite to the shaft hole 13 is formed. A pin 14 having a flange portion 14a is provided so as to project.

The outer bush 10 has an eccentric inner hole 10b larger than the outer diameter of the inner bush 12. The eccentric inner hole 10b is formed with an eccentric amount F, which is 6 mm in this example. The outer diameter is concentric with the axis C, and radial elongated holes 10a and 10a1 for accommodating the pin 14 and the flange portion 14a are formed on the inner spline shaft 7 side. A spring 15 for urging the pin 14 toward the inner spline shaft 7 is provided between the elongated hole 10a1 and the flange portion 14a.
Is interposed.

The middle bush 11 has an outer diameter that engages with the eccentric inner hole 10b of the outer bush 10.
An eccentric shaft hole 11a for accommodating
Is rotatably housed between the outer and inner bushes 10, 12. The eccentricity of the middle bush 11 is set to half the eccentricity F in the illustrated example, for example, 3 mm.

The slider 17 is formed in a convex shape that engages with the dovetail groove 18, and has a tool mounting shaft hole 19 facing the tool shaft hole 13 at the center. Further, a plurality of tool fastening screw holes 17a and 17b are provided inwardly in the radial direction with respect to the tool mounting shaft hole 19. In addition, at both ends, each unit 20A
Drive rack 21 is bolted.

The unit 20A is arranged symmetrically with respect to the axis C, and has a drive rack 21, a pinion 23, and
Drive piece 26, weight 27, housing 6
And a guide cavity 28 that is bored perpendicularly to the shaft.

Teeth are formed on the drive rack 21 at right angles to the sliding direction of the slider 17. The pinion 23 is supported by the housing 6 by a pinion shaft 24 and a pinion shaft bolt 25 so as to be engaged with the drive rack 21 and rotate. The rack portion 26a of the drive piece 26 is engaged with the pinion 23.

The drive piece 26 is slidably housed in a guide cavity 28. A rod-shaped weight 27 is screwed onto the drive piece 26. Also, a detachable cover 2 is provided outside the guide cavity 28.
9 is attached.

Next, the operation will be described. First, the spindle 3 is rotated in the state of the tool position adjusted in advance to perform cutting work.

Next, when changing the cutting outer diameter of the tool, the slide shaft 4 slides in the direction of the arrow in the illustrated example by the machine body. As a result, the outer helical spline 4a of the slide shaft 4 gives rotation to the inner helical spline 7c of the inner spline shaft 7, and in this case, the inner spline shaft 7 is rotated counterclockwise and the variable diameter means 9 operates. To do. That is, the outer bush 10 fastened to the inner spline shaft 7 with the bolt rotates about the axis C of the main shaft 3.
For example, in FIG. 5, when the angle Φ moves, the outer bush 1
The zero eccentric inner hole 10b moves from the position 10A to the position 10B. At the same time, the pin 14 provided on the inner bush 12 also moves to the position 14B. The inner bush 12 also moves along with this, but by the tool T attached to the tool shaft hole 13, only in the sliding direction of the slider 17, Y in the example of FIG.
-Move over the Y axis. At this time, the middle bush 11 fills the gap between the eccentric inner hole 10b of the outer bush 10 and the outer diameter of the inner bush 12 while moving. Therefore, the tool T is
The inner and inner bushes 10, 11 and 12 are held by engagement.
Since the inner and outer diameters of the outer, middle, and inner bushes that engage with each other are true circles, they can be accurately machined, and it is easy to eliminate play at the time of engagement.

As described above, the cutting outer diameter of the tool can be changed even during the cutting process, but since the weight is unbalanced by the changed amount, the weight correcting means 20 corrects as follows.

The slider 17 to which the tool T of the variable diameter means 20 is attached moves the dovetail groove 18 downward in FIGS. 2 and 3. In accordance with this movement, the drive rack 21 fastened to the slider 17 with the rack bolts 22 is shown as YY in FIG.
The pinion 2 which is located below the shaft and fixed in the housing 6
3 is rotated counterclockwise in FIG. Then, the drive piece 26, which is engaged with the pinion 23 at the rack portion 26a, moves upward with the weight 27 attached, and the unbalanced weight is corrected by changing the position of the center of gravity.

[0026]

Since the present invention is constructed as described above, it has the following effects. (1) The cutting diameter can be easily changed without play. (2) Since the constituent elements of the variable diameter means are perfect circles and straight lines, it is easy to guarantee accuracy. (3) Since the entire tool is moved instead of sticking out the tip, there is no deformation of the tip due to the moment and the precision of the cutting diameter is good. (4) Even if the amount of eccentricity is changed, the machining accuracy of the variable diameter means does not change, and the moment applied to the tip does not change, so the cutting diameter can be greatly changed.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a side sectional view of FIG.

FIG. 3 is a view taken in the direction of the arrow X including the AA cross section of FIG. 1.

FIG. 4 is a view on arrow Z of FIG.

FIG. 5 is a diagram showing an operating procedure of outer, middle, and inner bushes.

[Explanation of symbols]

 C ... Shaft F ... Eccentricity T ... Tool 1 ... Variable diameter boring adapter 2 ... Boring head 3 ... Spindle 4 ... Slide shaft 5 ... Key 6 ... -Housing 7 ... Inner spline shaft 7a ... Flange portion 7b ... Shoulder portion 7c ... Inner helical spline 8 ... Bolt 9 ... Variable diameter means 10 ... Outer bush 10a, 10a1. ..Long hole 10b ... Eccentric inner hole 11 ... Medium bush 11a ... Eccentric shaft hole 12 ... Inner bush 13 ... Tool shaft hole 14 ... Pin 14a ... Flange portion 15・ ・ ・ Spring 16 ・ ・ ・ Bearing 17 ・ ・ ・ Slider 17a, 17b ・ ・ ・ Screw hole 18 ・ ・ ・ Dovetail groove 19 ・ ・ ・ Tool mounting shaft hole 20 ・ ・ ・ Weight correction means 20A ・ ・ ・ Unit 21 ... Drive rack 2・ ・ ・ Rack bolt 23 ・ ・ ・ Pinion 24 ・ ・ ・ Pinion shaft 25 ・ ・ ・ Pinion shaft bolt 26 ・ ・ ・ Drive piece 26a ・ ・ ・ Rack part 27 ・ ・ ・ Weight 28 ・ ・ ・ Guide cavity 29 ・ ・ ・cover

Claims (3)

[Claims] 1. An inner spline shaft is provided which engages a slide wheel with an inner hole of a main shaft provided in a housing of a boring head via a helical spline, and which is rotated by axial movement of the slide wheel. A variable diameter boring adapter, characterized in that variable diameter means for moving a tool in a radial direction by rotation of a shaft is provided, and weight correction means connected to the variable diameter means is provided. 2. The variable diameter means comprises an eccentric shaft hole and a cylindrical inner bush provided with a pin at the shaft center, and an eccentric inner hole larger than the outer diameter of the inner bush, and slides the pin in the radial direction. An outer bush provided with a long hole that can be freely accommodated; a middle bush provided with an eccentric shaft hole that has an outer diameter that engages with the inner diameter of the outer bush and that houses the inner bush; a dovetail groove formed in the housing; The variable diameter boring adapter according to claim 1, wherein the slider is slidably accommodated in the dovetail groove. 3. The weight correcting means is slidably housed in a drive rack provided on a slider, a pinion meshing with the drive rack, provided on a housing, a guide channel formed in the housing, and a guide channel. 2. The variable diameter boring adapter according to claim 1, wherein the variable diameter boring adapter comprises a drive piece that meshes with the pinion and a weight that is screwed into the drive piece.