JPS5924443Y2 - Spherical cutting attachment - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a spherical cutting attachment that can be easily attached to a common lathe.

Conventionally, to cut a spherical surface on a normal lathe, a combination of a worm and a worm wheel is used.The worm is rotated with a handle to rotate the worm wheel 90 times, and then the worm wheel is attached to the chuck of the lathe using a bit attached to one end of the worm wheel. The machine was performing spherical machining on a rotating workpiece, but the roughness of the machined spherical surface was decreasing because the feed speed of the cutting tool by the handle was not constant.

Decrease in the roughness of the spherical surface can be prevented by using an NC lathe, but an NC mechanism is required.

The purpose of this invention is to provide an attachment that is normally attached to a lathe and can cut spherical surfaces with high precision without using an NC mechanism.

This invention will be explained below with reference to drawings showing embodiments.

A cross-feeding slide 3 is mounted on a slide base 2 of a lathe 1, and a tool rest 4 is mounted to the cross-feeding slide 3 with bolts.

A mounting plate 5 is attached to the side surface of the slide base 2 with bolts 6, and an arm holder 8 having a vertical insertion hole 7 is integrally attached to the mounting plate 5.

The center of the insertion hole 7 is the center line A-A of the chuck 30, which will be described later.
It is located above.

9 is a bushing fitted into the insertion hole 7.

Reference numeral 10 denotes an arm, which is composed of an arm portion 10a and a shaft portion 10b.The shaft portion 10b is rotatably inserted into the bushing 9, and a groove portion 10C provided in the shaft portion 10b has a positioning groove. The semicircular spacer 11 is fitted, and the same spacer 1
1 is fixed to the arm holder 8 with bolts 12.

A bed 13 having a dovetail portion 13a is integrally provided on the arm portion 10a, and a slider 14 having a dovetail groove 14a that is slidable by fitting into the dovetail portion 13a is provided on the bed 13.

A cutting tool holder 16 is mounted on the slider 14 via a spacer 15.

One end of a threaded rod 17 is screwed into a screw hole (not shown) provided in the slider 14, and a small diameter portion is provided near the other end of the threaded rod 17, and this small diameter portion is fixed to the end of the bed 13. It is rotatably fitted into the groove 18a of the bracket 18.

A knob 19 is attached to the other end of the threaded rod 17.

The tool holder 16 is provided with a tool insertion hole 20 for a tool 21 .

Bit insertion (the bottom surface 20a of L20 is low at both ends of the insertion hole 20 and high at the center).

The cutting tool 21 is inserted into the insertion hole 20, and the cutting tool holder 1
It is set by being pressed against the top 20b of the bottom 20a by three set bolts 22 screwed in from the top of the bottom 20a.

This makes it possible to accurately and quickly position the tip of the cutting tool 21 on a horizontal plane passing through the center C1 of the spherical surface of the workpiece 32.

A space 23 is provided between the bed 13 and the slider 14, into which a wedge 24 is inserted.

A clamp bolt 25 passing through the slider 14 is attached to the upper surface of the wedge 24, and the slider 14 is fixed to the bed 13 by a clamp nut 26 having a threaded hole that is screwed into the clamp bolt 25.

One end of a link 28 is pivotally attached to the lower surface of the arm 10a of the arm 10 via a shaft 27, and the other end of the link 28 is pivotally attached to the upper surface of the traverse slide 3 via a shaft 29.

Therefore, when the transverse slide 3 moves on the slide base 2, the center line of the link 28 is aligned with the axis 10 of the arm 10.
Since the arm 10 is eccentric from the axis C of the arm 10b, the arm 10 rotates about the shaft portion 10b as a rotation axis.

30 is a chuck of the lathe 1, and 31 is a chuck jaw.

32 is a cylindrical workpiece, and the line A-A is the center line of the chuck 30 and the workpiece 32.

The workpiece 32 rotates together with the chuck jaws 31.

The center line A-A can be perpendicular to the slide base 2.

C1 is the center of the processed spherical surface of the workpiece 32.

33 is a stopper that prevents the movement of the traverse slide 3;
It is attached to the slide base 2, and its attachment position will be described later.

When machining the workpiece 32 into a spherical surface, the workpiece 32 is gripped by the chuck claw 31, and the tip of the cutting tool 21 is positioned at the center of the workpiece 32 in the vertical direction (direction perpendicular to the plane of the paper in FIG. 2), that is, the center C1 of the machining spherical surface of the workpiece 32. The tool 21 is set in the tool holder 16 by adjusting the vertical position and inclination of the tool 21 using the set bolt 22 so that it is positioned on a horizontal plane passing through the tool holder 16.

Next, the knob 19 is rotated to move the slider 14 on the bed 13 so that the position of the tip of the cutting tool 21 is slightly larger than the machining diameter Dφ of the workpiece 32.

When this adjustment is completed, the clamp nut 26 is turned to fix the slider 14 to the bed 13, and the spacer 15, tool holder 16, and tool 21 integrated with the slider 14 are fixed to the bed 13.
is fixed to the bed 13.

Next, move the slide base 2 in the direction away from the chuck 30 (
This direction is called the vertical direction.

In FIG. 2, the direction is upward.

) to align the axis C of the shaft portion 10b of the arm 10 with the center C1 of the machining spherical surface of the workpiece 32, align the center line BB of the cutting tool 21 so that it passes through this center C1, and align the center line A-A. , B-B are orthogonal.

Next, the work 32 is rotated together with the chuck 30, and the traverse slide 3 is moved in the lateral direction (to the left in FIG. 2) on the slide base 2 at a constant speed.

As the traverse slide 3 moves, the arm 10 moves to the link 28.
The cutting tool 21 rotates around its shaft portion 10C as a rotation axis, and spherical cutting is performed while the center line B-B of the cutting tool 21 always passes through the center C1 of the spherical surface to be machined of the workpiece 32.

The center line B-B is rotated 90 degrees to the center line A- of the workpiece 32.
The above-mentioned stopper 33 is attached at a position that prevents the movement of the traversing slide 3 when A is met.

This operation performs rough machining of the spherical surface.

Next, return the cross-feed slide 3 by hand to its original position, that is, with the center line B-B of the cutting tool 21 perpendicular to the center line A-A of the workpiece 32, loosen the clamp nut 26, and turn the knob 19. After turning the tool appropriately to move the cutting tool 21 forward, turn the clamp nut 26 to fix the tool 21 to the bed 13 via the slider 14, and repeat the above operations 2 to 3.
Perform rough machining repeatedly.

After rough machining is completed, turn knob 19 slightly and set tool 2.
Precise machining is performed in accordance with the above-described procedure by reducing the amount of advance of step 1 to obtain a spherical shape with a desired diameter Dφ.

As mentioned above, this idea involves attaching an arm holder with an insertion hole in the vertical direction to the slide base of the lathe, arranging the insertion hole on the center line of the chuck of the lathe, and arranging the arm holder's insertion hole from the arm and shaft. The shaft part of the arm is inserted to make the arm swingable, and a tool holder that can be moved and fixed in the radial direction with respect to the insertion hole is attached to the arm part, and the lateral feed slide of the lathe that moves on the slide base is attached to the arm part. A stopper that is connected to the arm section by a link, swings the arm as the cross-feed slide moves, and stops the cross-feed slide when the center line of the chuck of the lathe matches the center line of the cutting tool attached to the tool holder. is provided on the slide base, and the tool holder is provided with a tool insertion hole having a bottom surface with both ends being low and the center being the top. can be fixed to the top of the cutting tool insertion hole with multiple set bolts, so the turning of the cutting tool around the center of the machining spherical surface is performed smoothly in conjunction with the transverse feed slide that moves at a constant speed, and the desired diameter can be achieved. It has the advantage that rough machining and precision machining of the spherical surface can be performed at will regardless of the simple mechanism, and the tip of the cutting tool can be accurately and quickly positioned on a horizontal plane that passes through the center of the spherical surface. This reduces the number of man-hours required to set the cutting tool, and allows cutting of a spherical surface with an accurate desired radius.

Furthermore, since the arm and therefore the tool holder can be rotated via the link by the linear movement of the transverse slide, the overall structure of the device is small and simple, and does not require a large space for installation.

Furthermore, since only the traverse slide moves on the slide base, the device as a whole does not require a large operating force.

[Brief explanation of the drawing]

Fig. 1 shows an exploded view of one embodiment of this invention, Fig. 2 shows a plan view of one embodiment when installed on a lathe, and Fig. 3 shows an exploded view of one embodiment of this invention.
The figure is an explanatory diagram of the installation of a cutting tool, FIG. 4 is an explanatory diagram of the main part of one embodiment, and FIG. 5 is an explanatory diagram of the operation of this invention. 1...Lathe, 2...Slide base,
3...Transverse feed slide, 7...Insertion hole, 8...Arm holder, 10...Arm 16...Bite holder, 20 ......Bite insertion hole, 20 a...Bottom surface, 20 b...
...Top, 21...Bite, 33...
・Stopper.

Claims (1)

[Scope of utility model registration request] an arm holder attached to a slide base of a lathe having a cross-feeding slide; a vertical insertion hole provided in the arm holder on the center line of a chuck of the lathe; and an arm that is inserted into the insertion hole and can swing; A cutting tool holder fixed to an arm so as to be able to move minutely in the radial direction with respect to the insertion hole is connected to the cross-feeding slide and the arm, and the arm is moved around the insertion hole of the arm holder by moving the cross-feeding slide on the slide base. It consists of a link for rotation, and a stopper for stopping the movement of the cross-feeding slide at a position where the center line of the chuck of the lathe and the center line of the tool attached to the tool holder match, and the tool holder has a tool insertion hole. However, this tool insertion hole has a bottom surface with both ends being low and the center being the top, and the tool is set by a plurality of set bolts so that the tip of the tool is located on a horizontal plane passing through the center of the machining spherical surface of the workpiece. A spherical cutting attachment that can be fixed to the top of the bottom.