JPS6085824A - Cutter for spiral grooving - Google Patents

Abstract

PURPOSE:To make a specially formed spiral groove cuttable in a simple and accurate manner, by installing a lot of both large and small diametral cutting edges on a cutter's peripheral part alternately at regular intervals in the circumferential direction, and dislocating them in order by each 1/n pitch in the axial direction. CONSTITUTION:A cutter 10 for cutting, for example, a spiral groove to be installed on a peripheral part of intermittent feed parts is constituted of a cylindrical body 11 consisting of carbon steel or the like and a lot of cutting edges 13 consisting of cemented carbide metals, etc., by way of example. In addition, each of these cutting edges 13 is one installing (n) pieces in the circumferential direction in many rows continuously, while in each cutting edge 13, large and small diametral ones are alternately continued in line, and adjacent cutting edges 13 are dislocated in order by each 2pi/n radian in the circumferential direction, besides by each 1/n pitch in the axial direction of the cylinder body 11. According to this cutter, such a specially formed spiral groove as being unequal in a lead angle can be machined in a simple and highly accurate manner.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a cutter suitable for cutting, for example, a spiral groove provided on the outer periphery of an intermittent feed component. An intermittent feed mechanism is known in which a screw member having a spiral groove provided on the outer periphery of the shaft is used, and by rotating this screw member by a predetermined angle, a movable member engaged with the spiral groove is reciprocated by a predetermined distance. ing.

FIG. 1 is a schematic configuration diagram of such an intermittent feeding mechanism, with 1
is a stepping motor, 2 is a bearing, 3 is a rotating connection member,
4 is a screw member, 5 is a guide bar, 6 is a moving member, 7 is a leaf spring, 8 is a tip, and 9 is a spiral groove.

A spiral groove 9 is formed on the outer periphery of the screw member 4, which is an intermittent feeding component.
One end of this screw member 4 is connected to the stepping motor 1 via the rotational connection member 3, and the other end is supported by the bearing 2. A guide bar 5 is installed parallel to the screw member 4, and a moving member 6 is attached to the guide bar 5.
is slidably fitted into the screw member 4 , and a pointed end 8 is provided at the lower end of the moving member 6 via a leaf spring 7 .
It is slidably fitted into the spiral groove 9 of.

When it is desired to intermittently feed the movable member 6 at a predetermined pitch using this feeding mechanism, the stepping motor 1 is intermittently energized to intermittently rotate the screw member 4 forward, thereby moving the movable member 6 to the guide bar 5. can be moved back and forth within a predetermined range.

By the way, the screw member 4, which is a conventional intermittent feed component used in the feed mechanism of this woodcutter, is as shown in its unfolded state in FIG. Therefore, by using a thread cutting lathe etc., it can be processed relatively easily and with high precision.
Rotation angle of 00.45°, 90°, 135°, 180'
, 225°, 270°, and 315°, if the movement of the moving member 6 is to be stopped intermittently at 8 points, the position of the moving member 60 may change proportionally due to variations in the rotation angle of the screw member 4 or discrepancies in rotation control. There was a problem with reliability because the system would shift and it would not be possible to stop at the proper position. Furthermore, as mentioned above, feed amount errors tend to occur due to deviations in the rotation control of the stepping motor 1, so in order to reduce this error, it is necessary to use a highly accurate, that is, expensive, stepping motor, or to use a spiral #- It is conceivable to use a special screw part with a 9° advance angle θ, but using an expensive stepping motor would be a cost disadvantage, and it would be difficult to machine a specially shaped spiral groove. This requires an NC lathe, a special thread cutting lathe, etc., and there is also the problem that it becomes an expensive part for intermittent feeding.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cutting cutter that can easily and accurately process a special-shaped spiral groove with uneven advance angles, while eliminating the drawbacks of the prior art described above.

[Summary of the invention]

In order to achieve this object, the present invention provides an outer circumference K of a cylindrical cutter with n large-diameter cutting blades and small-diameter cutting blades arranged alternately at equal intervals in the circumferential direction and at i pitches in the axial direction. The cutter is characterized by a large number of grooves arranged in a staggered manner, and the cutter is given a rotary cutting motion in the same direction as the workpiece to form a spiral groove with uneven advance angles on the outer periphery of the workpiece. .

[Embodiments of the invention]

Hereinafter, embodiments of the present invention will be described in detail based on FIGS. 3 to 12L9.

FIG. 3 is a side view showing an embodiment of a cutting cutter according to the present invention, and FIG. 4 is a front view of the cutter. The cutter 10 also includes a cylindrical body 11 made of carbon steel or the like, and a number of cutting blades 13 made of cemented carbide or the like. Fixed correctly. A mounting hole 12 with a key 1ift 12a is provided at the center of the cylindrical body 11, and the shape of the cutting edge 13 is chevron-shaped in cross section as shown in FIG. Become(・ru)

iiJ Each of the cutting blades 13 is provided in a number of continuous rows in the circumferential direction, and the outer diameter of each cutting blade 13 is such that large diameter ones and small diameter ones are arranged in succession alternately. The adjacent cutting edges 13 are shifted by Qw-radians in the circumferential direction of the main shaft 110 and by ↓ pitch in the axial direction of the groove body 11. , FIG. 6 is an explanatory view showing the state in which the cutter 10 is unfolded in the axial direction. As is clear from this figure, K is 22.5 degrees (';l-!) in the central direction in this embodiment. A total of 16 large and small cutting blades 13 shifted at equal intervals of !-radians) are sequentially shifted by one pitch in the axial direction, and these 16 cutting blades 13 are set as one row to form 12 rows of a-1. It is a provision. Therefore, the first large-diameter cutting blade al in the first row and the second small-diameter cutting blade a1 are offset by 225 degrees in the circumferential direction and by just τ hits in the axial direction, and similarly in one row. 16th small diameter cutting blade all and 2
The first large-diameter cutting blade b1 in the row also has a diameter of 1 in the circumferential direction.

22.5 degrees, just τ hit in the axial direction, 122nd row, 1st
The sixth small-diameter cutting edge t16' is deviated in the same manner.

7 to 9 are side views of cutting states using the cutter 10 described above, and 14 indicates a workpiece. The workpiece *14 is a round bar having a diameter of j of the cutter 10, and the workpiece 14 and the cutter 10 are both rotated counterclockwise at a rotation ratio of 1:1.

Now, as shown in FIG. 8, the cutter 10 and the workpiece 1
4 in the direction of the arrow at an equal rotation ratio of 1:1, and
-xo is applied by a predetermined amount toward the center of the workpiece 14, the contact locus between the cutting edge of the cutting blade 13 and the workpiece 14 becomes approximately a straight line, and the workpiece 14 has a large diameter cutting blade a1. The shaded area is cut by. As a result, a V-shaped groove A1 having the same cross-sectional shape as the cutting blade 13 is formed on the outer periphery of the workpiece 14.
is formed, and this groove A1 is parallel to a perpendicular line perpendicular to the axis of the workpiece 14. Since the diameter of the cutter 10 and the workpiece 14 is JA, the circumferences of each rotate in the direction of the arrow at different circumferential speeds.Therefore, the small-diameter cutting blade a1 next starts a contact trajectory with the workpiece 14. The workpiece 14 has the cutting edge a described above.

A new V-shaped groove A2 is formed at a position shifted 16 pitches in the axial direction from the groove A2 formed by the groove A2. Further, when the cutter 10 and the workpiece 14 rotate, as shown in FIG. Cutting blade a1
A V-shaped groove A having the same depth is formed. Therefore,
The groove A formed by this cutting edge a is the groove A formed by the cutting edge a2.
, there is a deviation in the axial direction, and the groove A1 due to the cutting edge a1
There is a selling pitch deviation in the axial direction. However, the depth of the groove A2 formed by the small-diameter cutting blade a2 is shallower than the depth of the groove A1°A formed by the large-diameter cutting blades a1 and cutting blades a3. and the cutting edge a3.
The connecting portion of A is chamfered by the groove A formed by the cutting edge a2. Thereafter, by rotating the cutter 10 once, a groove with a relatively long linear bottom formed by a large-diameter cutting blade and a chamfering groove formed by a small-diameter cutting blade are formed on the outer circumference of the workpiece 14. , a total of 16 pieces alternately in the circumferential direction, and
6 cut J-10 blade rows (121 rows of a-t in this example) in a state that is sequentially shifted by a pitch in the axial direction.
It is formed with a threaded portion of the same length. Note that it is difficult to cut a groove of the desired depth with one contact trajectory, so in this case, the feed amount of the cutter 10 is reduced to reduce the cutting amount of each cutting edge 1301 times (and The workpiece 14 and cutter 10 may be rotated continuously.

Figure 1O is a front view of the part for intermittent feed processed by the cutter 10 described above, Figure 11 is a right side view of the part for intermittent feed shown in Figure 10, and Figure 12 is the intermittent feed part shown in Figure 10. It is an explanatory diagram showing the lead angle of the parts, 15 is a shaft,
16 is a groove portion, 17 is a chamfered portion, and 18 is a spiral groove.

A large number of groove portions 16 having linear groove portions and chamfered portions 17 are alternately formed on the outer peripheral portion of the shaft 15 over a predetermined range. The groove portions 16 are parallel to the perpendicular line Yic orthogonal to the axis X of the shaft 15, that is, the advance angle 01 is zero, and eight groove portions are formed at equal intervals in the circumferential direction and are shifted by one pitch in the axial direction. Further, eight chamfered portions 17 are provided at equal intervals in the circumferential direction, and are arranged on the shaft 1 .

However, since the groove depth of this chamfer 17 is shallower than that of the groove 16, as shown in FIG. The groove hll16 and the chamfered portion 17 form one spiral @18, and the chamfered portion 17 acts as a feeding portion for a moving member to be described later.

The pointed end 8 of the moving member 6 shown in FIG. 1 described above is slidably fitted into the spiral groove 18 of the intermittent feed component having such a structure. In a feeding mechanism equipped with such an intermittent feeding component, when the pointed end portions 8 slide within the chamfered portions 17 as the shaft 15 rotates,
When the movable member 6 moves in a predetermined direction in accordance with the advance angle θ2 of the chamfered portion 17 and the tip portion 8 comes into the groove portion 16,
The power supply to the stepping motor 1 is cut off, and the movement of the moving member 6 is stopped. In this manner, the movable member 6 is fed intermittently by being fed at the chamfered portion 17 and stopped at the groove portion 16, but each movement of the movable member 6 is smoothed by the chamfered portion 17. As mentioned above, groove 1
6, the advance angle θ1 is zero, so even if the rotation angle of the intermittent feeding component deviates somewhat, the stopping position of the # moving member 6 is appropriate. Because of this tx, the accuracy of the stepping motor is not required to be very high, and even inexpensive stepping motors can be used.

In addition, in the above embodiment, 12 rows of cutting blades 13 having a total size of 16IIIA, which are shifted at equal intervals of 22.5 degrees in the circumferential direction, are sequentially shifted in the axial direction by "τ pitch" will be explained. However, the number and spacing of the cutting blades 13 according to the present invention are not limited to this, and the cutter 1
0 and the diameter ratio of the workpiece 14 and the rotation ratio during cutting are not limited to the above embodiments.

〔Effect of the invention〕

As explained above, according to the present invention, a spiral fermentation with uneven advance angles can be processed more easily and in a shorter processing time than when processed using an NC lathe or a special thread cutting lathe. Moreover, since the accuracy of the spiral groove is determined by the IR degree of each cutting edge of the cutter, it is possible to provide a spiral groove 149 in the stack. If a member having such a spiral shape is used for the intermittent feeding rock 44, etc., it is possible not only to increase the stopping position of the moving member without using a high-precision, high-turn stepping motor, but also to increase the stopping position of the moving member. can be sent smoothly.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of the feeding mechanism, Fig. 2 is an explanatory diagram showing the advance angle of a conventional intermittent feeding component, Figs. 3 to 12 show embodiments of the present invention, and Fig. 4 is a front view of the cutter shown in FIG. 3; FIG. 5 is an enlarged sectional view of the cutting blade; FIG. 6 is an explanatory diagram showing the expanded state of the cutting blade; 8 and 9 are side views showing the cutting state of a workpiece by the cutter of the present invention, and FIG. 10 is a front view of the intermittent feed part machined by the cutter shown in FIG. 11 is a right side view of the intermittent feed component shown in FIG. 10, and FIG. 12 is an explanatory diagram showing the advance angle of the intermittent feed component shown in FIG. 10. 10... Cutter, 11... Curved body, 13...
... Cutting blade, 14 ... Workpiece, 16 ...
... Groove section, 17... Chamfer section, 18...
・Spiral groove. Figure 1 ρ Figure 2 Angle Figure 6 Figure 7 Figure 13 Figure 8 Figure 10 Figure 8

Claims (1)

[Claims] In a device that forms a spiral groove on the outer circumference of a workpiece by rotating the workpiece and a cutter that cuts the workpiece in the same direction, a large groove is formed on the outer circumference of the cylindrical cutter. A cutter for cutting a spiral groove, characterized in that a large number of large-diameter cutting blades and small-diameter cutting blades are provided alternately at equal intervals in the circumferential direction, and are sequentially shifted by 1 pitch in the axial direction.