JPS58102611A - Inner groove work device - Google Patents

Abstract

PURPOSE:To enable a precise inner groove work on the deep inner periphery of a comparatively small hole by inserting only a cutting tool into a work hole. CONSTITUTION:Only a cutting tool 40 is inserted into a work hole 46, thereby the inner diameter of the work hole 46 under an inner groove work becomes small to the utmost, and a large displacement of the edge portion can be available regardless of the small displacement at the base section of the cutting tool 40 when the cutting tool 40 is swinging, thus a deep inner groove work is made feasible even though the aperture of the work hole is small in diameter. That is, a cutting tool holder 35 slowly swings around a support axis 36 within a predetermined angle in relation to the axial line 15 of a spindle 13, the cutting tool 40 rotates around the support axis 36 including at a predetermined angle against the axial line 15, the cutting edge cuts the peripheral surface of the work hole 46, and an inner groove 47 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for forming grooves on the inner periphery of a hole.

For example, in a precision boring machine, the cutting tool holder and cutting tool at the tip of the boring bar are inserted into the hole, and the tool is moved in the radial direction of the hole. It is rotated to machine grooves on the inner peripheral surface of the machined hole. In the case of this machining, if the hole to be machined has a very steep inner diameter, it is relatively easy to process, but if the hole to be machined has a small inner diameter and the inner circumferential surface is at a deep position, the grooves should be machined at a deep position.
KFi, precision machining is almost impossible. The reason for this is that the means of moving the boring bar is located far away from the cutting edge of the cutting tool, and the outer diameter of the tool holder is limited by the inner diameter of the hole to be machined. This is because one parallel movement causes deflection of the boring bar and other members, which weakens the initial groove machining. Moreover, since the stroke during parallel movement is only a small amount, it is difficult to make deep grooves within the pores of several tq.

On the other hand, for example, Japanese Patent Publication No. 52-11070 ``Tool for Machining Internal Diameter Grooves'' discloses a means for moving the main shaft and moving only the cutting tool holder at the tip in the radial direction inside the machining hole. However, even with this method 4, the tool holder goes inside the processing hole, so it is nearly impossible to machine a groove in a hole as small as a few millimeters due to the structure.

SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus capable of precisely machining a deep inner circumferential surface of a relatively small hole.

Based on the above object, the present invention is made by inserting only a cutting tool such as a cutting tool into a processing hole, giving the cutting tool a predetermined swing angle displacement centering on the base end of the cutting tool, and moving the tip of the cutting tool. Rotation for cutting is applied to the cutting tool while applying a large amount of displacement to the cutting edge.

Hereinafter, the present invention will be explained in terms of monthly salary based on an embodiment shown in the drawings.

First, FIGS. 1 to 4 show the premise of the internal groove machining device 1 of the present invention and the driving portion thereof. This part' is constructed around the frame 2, is supported horizontally on the frame 2F1 and a base 3 so as to be slidable in the horizontal direction, and is reciprocated (forward and backward) by a powerful drive means shown in the figure. A fixed plate 4 holds a motor 5 as a drive source at the rear end of the frame 2 . The motor shaft 6 is meshed with an output gear 7 and a winding gear 8K.

This gear 8 shaft 11 and bearings 12 at both ends make the frame 2
At the same time, two other gears 9 and 10 having the same number of teeth are fixed. - On the other hand, the frame 2 rotatably supports a cylindrical spindle 13 inserted in the horizontal direction from the front to the rear K inside thereof by front and rear bearings 14ff. This spindle 13#I'i
It has a center hole 16 that is concentric with the axis 15 during rotation, and in this part the rear bearing 17 and the membrane sliding bearing 18VC are connected.
The camshaft 19 is rotatably supported. A threaded portion 20 is formed at the rear end portion of this camshaft 19, and a driven gear 21 is screwed into this portion and fixed by a collar 22. This driven gear 21 meshes with the gear 9. Also, the rear end portion of the spindle 13 [follower gear 2
3 is inserted in a non-rotating state with a key 24, and is fixed by tightening with a nut 26 screwed into the threaded portion 25 from the rear end portion. This driven gear 23Fi gear 10Wc
The number of teeth of this driven gear 23 is the same as that of the camshaft 1.
The number of teeth is set to be different from the number of teeth of the driven gear 21 of No. 9 by, for example, one tooth root degree. Further, a pair of guide plates 27 are mounted on the tip end surface of the spindle 13 in an opposing state using mounting screws 28. The opposing surfaces X of the pair of guide plates 27 and the groove surface of the spindle 13 form a rectangular guide surface 29, and this guide surface 29 can freely displace the slide body 30 in a direction crossing the axis 15. In the embodiment, the slide body 30 has a convex cross section and rotatably supports a cam follower 31 at a position corresponding to the end surface of the force shaft 19. Cam follower 3
1 is a positive cam groove 32 formed on the end surface of the camshaft 19;
It is located inside. This cam groove 32 is formed in an annular shape eccentrically with respect to the axis 15 during rotation.

Next, FIGS. 5 to 7 show the main parts of the present invention.

A pair of guide plates 27 have a pair of bearing bodies 33 on each surface.
is supported. The bearing body 33 has an L-shape and is fixed to the guide plate 27 with a mounting screw 34. The pair of bearing bodies 33 support the cutter tool holder 35 between them so as to be swingable from a pair of left and right support shafts 86M. Support shaft 36Jf
It is press-fitted into both sides of the cutting tool holder 35 in a state perpendicular to the axis 15 of the spindle 13, and the bearing body 3
It is rotatably inserted into the shaft hole 37 of No. 3. The cutter hole 3B is located at the tip of the extension of the axis 15 of the cutter holder 35a.
and has a KU-shaped engagement groove 39 at the rear end. The cutter hole 38 is for fixing a cutter 40 such as a cutting tool, and the proximal end of the cutter 4oFi is inserted into the cutter hole 38 and is fixed with a set screw 41 to prevent removal. Also, the shaft 4 of the spindle 13 with the retaining groove 39
It is provided along the direction 115 and engages with the retaining shaft 42. The engagement shaft 42 and the engagement groove 39 constitute an engagement means. This retaining shaft 42#Ii is fixed to the shaft plate 43, and is fixed to the center of the front side of the slide body 30 by this shaft plate 43Fi fixing screw 44.

Next, the operation of the inner groove machining device ll will be explained. The workpiece 45 has a processing hole 46 in the front position of the cutting tool 40.
Fixed to match.

In this state, the frame 2 moves forward on the base 3, and the cutting tool 40 is inserted into the processing hole 46. Of course, at this time the cutting tool 40
is located at a position coinciding with the axis 15 of the spindle 13.

In this state, the motor 5 transmits its rotation to the spindle 13 and the hiccup shaft 19 via the output gear 7 and the gears 8, 9, 10, and the driven gears 21, 23. Gears 9, 10
Since the numbers of teeth of the driven gears 21 and 23 are the same, and the numbers of teeth of the driven gears 21 and 23 are different, the spindle 13 and the camshaft 19 rotate in a differential state with a slight rotation difference. This spindle 13
The rotation of the blade 40 corresponds to the rotation of the blade 40. on the other hand,
The rotation of the camshaft 19 is caused by the cam groove 32 and the cam follower 31.
The slide body 3 (l) is converted into a reciprocating linear motion in the diametrical direction of the spindle 13, that is, in the direction perpendicular to the axis 15 during rotation of the spindle 13. The relative rotation speed when moving inside matches the differential speed between the camshaft 19 and the spindle 13. In this way, the slide body 30 moves slowly in the diametrical direction while rotating. , the displacement is determined by the engagement shaft 42 and the engagement groove 3 as a retaining means.
9 is transmitted to the cutting tool holder 35 as a rotational displacement. As a result, the cutter holder 35 slowly swings the spindle 13 around the support shaft 36 within a predetermined angle with respect to the axis 15. As a result, the cutting tool 40 is inclined at a predetermined angle with respect to the axis 15 of the spindle 13 around the support shaft 36 while rotating, so based on the inclination, the cutting edge of the cutting tool 40 cuts the curved surface of the machined hole 46, and there -1 to form an annular inner groove 47 on the circumferential surface. This groove machining is completed when the slide body 30 makes one reciprocation with respect to the guide plate 27&'r, that is, when the car follower 31 turns inside the force groove 32 only once. Here, since the inclination angle of the cutting tool 40 is determined by the lift of the cam groove 82, it can be arbitrarily set by selecting the lift of the cam groove 32 on the maximum diameter of the processing groove to a desired value. Of course, after machining 40 cutting tools, the axis line 15
It is pulled out from the processed hole 46 after being returned to a state consistent with that.

In the above embodiment, a gear train generates differential rotation between the spindle 13 and the force shaft 19, and a cam mechanism generates reciprocating linear motion of the slide body 30C, but these parts It can also be replaced with other known ones. Further, the guide plate 27 and the bearing body 33ki are members that swingably support the cutting tool holder 35, but these may be formed as a part of the spindle 13. Further, the engagement means between the slide body 30 and the cutter holder 35 is not limited to the engagement shaft 42 and the engagement groove 39, but may also be constituted by other mechanisms such as a rack or a pinion.

According to the present invention, since only the cutting tool enters the inside of the machined hole, the diameter of the machined hole for internal groove machining is made as small as possible,
Also, when the cutting tool swings, a large amount of displacement can be obtained at the cutting edge despite a small amount of displacement at the base end of the cutting tool.
It is possible to machine deep internal grooves even if the hole has a small inner diameter on the opening surface, and even if the cutting tool itself bends, by adding this amount of deflection and setting the inclination angle of the cutting tool, high accuracy can be achieved. The inner groove can be machined reliably.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway side view of the driving part of the internal groove machining device of the present invention, Fig. 2 is a front view of its tip, Fig. 3 is a plan view of the tip, and Fig. 4 is a cam groove portion. FIG. 5 is a front view, FIG. 5 is a sectional view of the main part of the present invention, FIG. 6 is a front view thereof, and FIG. 7 is a sectional view taken along the line ■--■ in FIG. 5. 1... Inner groove processing device, 5... Motor, 13
...Spindle, 15...Axis line, 19...
・Cam shaft, 30... Slide body, 35... Cutting tool holder, 36... Support shaft, 39... Engagement groove, 4
0... Cutting tool, 42... Engagement shaft, 45... Workpiece, 46... Machining hole, 47... Inner groove. Figure 1 Figure 4 Figure 5 First 6th r! 1

Claims (1)

[Claims] A spindle that is rotated by a drive source, a slide body supported at the tip of the spindle so as to be freely displaceable in a direction crossing the axis of rotational movement, and a blade holder that is swingably supported by a member fixed to the tip of the spindle. and a retaining means for a cutting tool holder supported on the slide body.