JP2002233915A - Shaving cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep the sharpness and extend the life. SOLUTION: Two or more cutter 17 of a serration 34 of a shaving cutter are continuously disposed in the order of working for one tooth of a work gear in the direction of tooth trace in the same position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaving cutter for finishing a gear tooth surface, and more particularly to a serration arrangement of teeth of a shaving cutter used in a plunge cut shaving method and an underpass shaving method.

[0002]

2. Description of the Related Art Shaving is generally performed by shaving a substantially disk-shaped shaving cutter 10 provided with gear-shaped teeth 11 on the outer periphery as shown in FIG. The tooth 11 of the shaving cutter 10 is combined with the tooth of the work gear 20 with a certain crossing angle α between the cutter shaft 12 and the tooth surface of the gear of the work gear 20 is finished by a sliding action caused by a rotational motion. Is the way. In addition, as shown in FIG.
Serrations 14 provided with a plurality of grooves at regular intervals are formed on the tooth surfaces 13 of the teeth 11 of the
5. The groove is called a serration groove 16, and the ridges at both ends of the land 15 are used as cutting edges 17.

Here, the shaving method using a shaving cutter includes a conventional shaving method,
There are four types: diagonal shaving, underpass shaving, and plunge cut shaving.
In the conventional and diagonal shaving methods, the shaving process is performed on the work gear 20 while moving the shaving cutter 10 parallel or obliquely to the work gear shaft 22 in the relative movement direction during the shaving process. That is, the shaving cutter 1 is moved in the
Since the zero cutting edge 17 is fed, even if the cutting edges 17 of all the serrations 14 are arranged at the same position without shifting in the tooth trace direction, the tooth surface of the cut gear 20 can be finished.

[0004] In contrast to the conventional transverse and diagonal shaving methods of the transverse feed system, the gear
As a method without relative axial feed of the shaving cutter 10 and the shaving cutter 10, there is a plunge cut shaving method in which there is no relative feed, and an underpass shaving method in which feed is performed in a direction perpendicular to the cut gear shaft 22. These methods are
It is said that stepped gears can be easily processed and are suitable for finishing processing of mass-produced gears.

Since the shaving cutter 10 used in the plunge cut and underpass shaving method does not have a relative axial feed between the shaving cutter 10 and the gear 20 to be cut, each tooth 1 of the shaving cutter 10 is not used.
If the positions of the land 15 and the serration groove 16 of the first serration 14 are the same in the tooth trace direction, the position of the cutting edge 17 of the serration 14 is the same in the tooth trace direction of the work gear 20, so that the The tooth surface has irregularities in the direction of the tooth traces, and the entire tooth surface cannot be finished smoothly. Therefore, in the shaving cutter 10 used for the plunge cut and the underpass shaving method, as shown in FIG. 3, the positions of the serrations 14 of the respective teeth 11 are slightly shifted in the direction of the tooth traces. The provided serrations 14 are called differential serrations.

Next, the differential serration will be described. FIG. 3 schematically shows a positional relationship between the teeth 11 of the shaving cutter 10 and the teeth 21 of the gear 20 when shaving the gear 20 using the shaving cutter 10 having the teeth 11 which are set as differential serrations. Those are shown in FIG. Here, for example, the teeth 11 of the shaving cutter 10 are assumed to have thirteen teeth, and the teeth 11 are arranged in the order in which they are arranged along the outer circumference.
It is assumed that the teeth 21 of the gear 20 to be machined have five teeth and the numbers 21 to 21 are arranged in the order in which they are arranged along the outer circumference.

FIG. 5 shows the arrangement of the serrations 14 of the teeth 11 of the shaving cutter 10 in the order in which they are arranged along the outer periphery of the shaving cutter 10 (in the order of 11a to 11m). As shown in FIG. 5, the serrations 14 of the shaving cutter 10 are arranged so as to be shifted in the direction of the tooth trace.

[0008] Considering that the tooth 21a of the shaving cutter 10 and the tooth 21a of the shaving cutter 10 shown in FIG.
When the tooth 21 of the gear 20 makes one rotation, the tooth 21 of the
Comes into contact with the teeth 11 f of the shaving cutter 10, and when it makes another rotation, the teeth 2
1 is in contact with the teeth 11k of the shaving cutter 10.
In this way, every time the gear 20 is rotated, the teeth 21 of the gear 20 become the teeth 11 of the shaving cutter 10.
a, 11f, 11k, 11c, 11h, 11m,... are abutted and cut in this order, and shaving is performed.

As described above, one tooth 21 of the cut gear 20
FIG. 6 shows an arrangement of the serrations 14 of the teeth 11 of the shaving cutter 10 in the order in which the serrations work. As shown in FIG. 6, the serrations 14 of the teeth 11 of the shaving cutter 10 are arranged so as to be gradually shifted in the order in which they act on the teeth 21 of the cut gear 20.
Similarly, the serrations 14 are gradually shifted in the order in which they act on the other teeth 21 to 21 of the gear 20 to be machined. The tooth surface of the cutting gear 20 can be finished.

[0010]

However, in the above-described shaving cutter 10, if the cutting edge 17 of the serration 14 is worn out by shaving and the sharpness is reduced, the processing accuracy of the tooth surface of the gear 20 to be cut is reduced. As a result, the shaving cutter 10 itself has to be replaced, and there is a problem that the life of the shaving cutter 10 is short.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a shaving cutter that maintains good sharpness of a shaving cutter and has a long life.

[0012]

Means for Solving the Problems To solve the above problems,
In order to achieve such an object, the present invention has a plurality of teeth provided with serrations on the tooth surface, and the positions of the cutting edges of the serrations are sequentially shifted in the tooth streak direction to form a differential serration. In the shaving cutter, the cutting edge of the serration acting on the first rotation, second rotation,..., N-th rotation (N ≧ 2) of one tooth of the gear to be machined. Are characterized by the same position. That is, one tooth of the gear to be machined is N
Each time it rotates, it has a differential serration in which the position of the serration cutting edge acting on this one tooth is sequentially shifted. Further, in order to obtain such a shaving cutter, for example, a plurality of teeth having serrations on a tooth surface are provided, and the positions of the cutting edges of the serrations are sequentially shifted in the tooth streak direction to obtain a differential serration. In shaving cutter,
One tooth of the gear to be machined corresponds to one tooth of the gear to be machined.
The positions of the cutting edges of the serrations acting on the second rotation, the second rotation,..., The Nth rotation (N ≧ 2) are arranged so that a plurality of (for example, two) cutting edges are the same in the tooth streak direction. Good.

[0013] With such a configuration, among the serrations arranged at the same position in the tooth lead direction by a plurality of sheets, the cutting edge of the serration that first acts on one tooth of the gear to be cut serves as a rough blade. The serrated cutting edge acting on the same position of one tooth of the gear to be cut after the second time plays the role of the finishing tooth. Thereby, even if the cutting edge of the serration that plays a role of a rough blade acting first on one tooth of the gear to be cut in the shaving process is worn and loses sharpness, the tooth of the tooth of the gear to be cut is reduced for the second and subsequent times. Since the finishing is performed by the serrated cutting blade that plays the role of the finishing blade acting on the same position, the precision of the tooth surface shape of the gear to be cut can be favorably maintained. In addition, even if the cutting edge of the serration that plays the role of a rough blade is slightly sharpened, it is possible to cut the tooth surface of the gear to be cut, and the cutting edge of the serration that plays the role of the finishing blade finishes, The life of the shaving cutter is improved without reducing the accuracy of the tooth surface shape of the gear to be cut.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the attached drawings, but the same or similar parts as those of the above-mentioned prior art will be denoted by the same reference numerals and description thereof will be omitted. FIG. 1 is an explanatory view showing the arrangement of the serrations of the shaving cutter according to the embodiment of the present invention, and FIG. 2 is the arrangement of the serrations of the shaving cutter arranged in the order in which they act on one tooth of the gear to be cut. FIG.

The shaving cutter according to the embodiment of the present invention has a substantially disk shape, and has teeth 31 along its outer periphery. A serration 34 having a plurality of grooves at regular intervals is formed on the tooth surface of the tooth 31 of the shaving cutter.
The ridges at both ends of the land 15 are used as cutting edges 17.

Here, the teeth 31 of the shaving cutter according to the present embodiment have, for example, thirteen teeth.
Numbers from 1a to 31m are assigned, and the gear 21 to be machined by the shaving cutter is assumed to have five teeth 21 and numbered from 21 to 21. The serrations 34 are arranged in the order in which the teeth 31 provided along the outer periphery of the shaving cutter according to the present embodiment are arranged.
1 are shown in FIG.

Further, in the same manner as in the above-mentioned prior art, the order (31a, 31f, 31) in which the serration 34 of the shaving cutter acts on one tooth 21 of the gear 20 to be cut.
k, 31c, 31h,...) are shown in FIG.
As shown in FIG. 2, the serrations 34 of the teeth 31 of the shaving cutter according to the present embodiment are arranged at the same position in the tooth streak direction two by two consecutively in the order in which they act on one tooth 21 of the cut gear 21. Have been. That is, in FIG. 2, the set A of the serrations 34 of the teeth 31f, k of the shaving cutter is arranged at the same position in the tooth trace direction, and the set B of the serrations 34 of the teeth 31c, h is located at the same position in the tooth trace direction. Two serrations 34 are arranged in a row at the same position in the tooth trace direction as a set.

As shown in FIG. 9, the shaving cutter having the above-described structure is provided with a predetermined cross angle α between the cut gear shaft 22 and the shaving cutter shaft 12 so that the tooth of the shaving cutter can be formed. 31 is combined with the teeth 21 of the gear 20, and the tooth surface of the teeth 21 of the gear 20 is finished by a sliding action caused by the rotational motion.

First, consider the process of shaving the teeth 21 of the gear 20 to be cut. Teeth 21 of the gear 20
Is the serrations 34 of the shaving cutter teeth 31a.
Then, cutting is performed by the set A of the serrations 34 of the teeth 31f, k. Here, since the set A of the serrations 34 of the teeth 31f and k of the shaving cutter is arranged at the same position without shifting in the tooth streak direction, the cutting edge 1 of the serrations 34 of the teeth 31f is obtained.
7 plays the role of a rough blade for the main cutting, and then the teeth 31
The cutting edge 17 of the k serration 34 plays a role of a finishing blade for finishing the surface. Next set B
In the same manner, (the serrations 34 of the teeth 31c and h), the shaving of the gear 20 proceeds by repeating the processing of the teeth 21 of the gear 20 and the subsequent set C. . The other teeth 21 of the gear 20
The shaving process is similarly performed on to 21, and the shaving process on the gear 20 is completed.

According to the shaving cutter according to the present embodiment, the serrations are successively arranged at the same position in the tooth streak direction two by two when arranged in the order of acting on one tooth 21 of the cut gear 20. Are formed, and among the sets A, B,..., The cutting edge 17 of the serration 34 that acts on one tooth 21 of the work gear 20 first serves as a rough blade. Then, the cutting edge 17 of the serration 34 acting on the same position of one tooth 21 plays the role of a finishing blade, so that the cutting gear 20
The accuracy of the tooth flank shape is improved. In addition, even if the cutting edge 17 of the serration 34 which plays a role of a rough blade acting first on the one tooth 21 of the gear 20 to be cut by shaving wear is worn and loses sharpness, a finish which acts on the same position for the second time. Since the finishing process can be performed by the cutting blade 17 of the serration 34 which plays the role of a blade, the precision of the tooth surface shape of the work gear 20 can be maintained well. Further, even if the cutting edge 17 of the serration 34 which plays the role of a rough blade is slightly sharpened, it is possible to cut the tooth surface of the gear 20 to be cut. Since the finishing process, without reducing the accuracy of the tooth surface shape of the gear 20 to be cut,
The life of the shaving cutter is improved.

In this embodiment, the number of the servings 34 of the shaving cutter continuously arranged at the same position in the tooth lead direction in the order in which the serrations 34 act on one tooth 21 of the cut gear 20 is two. However, three or more teeth 31 may be arranged in the same direction in the tooth streak direction to form a set. Further, taking into account the processing accuracy and the like when processing the serrations 34 on the teeth 31 of the shaving cutter, ±
It may be shifted from the target position within a range of 0.07 mm, preferably ± 0.05 mm.

[0022]

As described above, according to the present invention,
With respect to one tooth of the gear to be cut, the first,...
Since the cutting edges of the serrations of the teeth of the shaving cutter acting in 2) are arranged at the same position in the tooth trace direction, they play the role of rough blades acting first on one tooth of the gear to be cut in shaving processing. Even if the cutting edge of the serration wears and loses its sharpness, the serrated cutting blade plays a role of a finishing blade acting on the same position of one tooth of the cut gear after the second time. The precision of the tooth surface shape can be maintained satisfactorily. In addition, the serrated cutting edge that plays the role of a rough blade can cut the tooth surface of the work gear even if the cutting edge is slightly sharpened. The life of the shaving cutter is improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram in which serration arrays of a shaving cutter according to an embodiment of the present invention are arranged in the order in which they are arranged.

FIG. 2 is an explanatory diagram in which serration arrangements of a shaving cutter according to an embodiment of the present invention are arranged in the order in which they act on one tooth of a cut gear.

FIG. 3 is an explanatory diagram showing a shape of a differential serration of a general shaving cutter.

FIG. 4 is an explanatory diagram showing a positional relationship between a shaving cutter and a gear to be cut when performing shaving processing.

FIG. 5 is an explanatory diagram in which the arrangement of differential serrations of a conventional shaving cutter is arranged in the order in which they are arranged.

FIG. 6 is an explanatory diagram in which the arrangement of differential serrations of a conventional shaving cutter is arranged in the order of acting on one tooth of a cut gear.

FIG. 7 is a schematic view showing a general shaving cutter.

FIG. 8 is an enlarged view of a main part of the shaving cutter in FIG. 7;

FIG. 9 is a schematic view showing a state of a shaving process of a general shaving cutter.

[Explanation of symbols]

 15 Land 16 Serration Groove 17 Cutting Edge 20 Work Gear 21 Tooth 22 Work Gear Shaft 31 Tooth 34 Serration

Claims (1)

[Claims] 1. A shaving cutter having a plurality of teeth having serrations on a tooth surface, wherein a position of a cutting edge of the serration is sequentially shifted in a tooth lead direction to form a differential serration. For one tooth of the gear,
A shaving cutter wherein the positions of the cutting blades of the serrations acting on the rotations, the second rotation,..., The Nth rotation (N ≧ 2) are the same.