JP2005177938A - Bevel gear cutter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bevel gear cutter capable of restraining running cost to create a tooth profile at low cost. <P>SOLUTION: This bevel gear cutter 1 includes a cutter main body 2 furnished with a rotary axis and a plurality of blades 10, 20, 30, 40 arranged at specified intervals in the circumferential direction of the cutter main body, and the blades are constituted so as to include blade parts 16, 26, 36, 46 to process tooth spaces and bottoms of a gear and mounting recessed parts 13, 23, 33, 43 on which the blade parts are dismountably mounted. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a bevel gear cutter, and more particularly, to a bevel gear cutter suitable for being applied to processing of a bent tooth bevel gear and the like.

The gear is a mechanism that transmits energy received from the driving unit to the driven unit, and is selected according to the positional relationship between the driving unit side shaft and the driven unit side shaft. For example, curved bevel gears are suitable for intersecting axes. This bent bevel gear can achieve a high strength and smooth rotation as compared to a straight bevel gear.
It is known to use a bevel gear cutter for processing such a gear. In this cutter, an outer blade for processing a tooth groove on the outer side (outside) in the radial direction from the rotation axis is processed on the outer periphery of the cutter body, and a tooth groove on the side (inner side) in the radial direction near the rotation axis. In addition to the inner blade, it is arranged separately for the bottom blade for processing the tooth bottom connecting each tooth gap.

Specifically, the outer cutter blade on which the outer cutter is formed, the inner cutter blade on which the inner cutter is formed, and the bottom cutter blade on which the bottom cutter is formed constitute one set, and a plurality of sets of blades are arranged in the circumferential direction of the cutter body. Are arranged at predetermined intervals.
Each of these blades is configured integrally with each blade portion, and is bolted to the cutter body, and each blade portion is formed by polishing the blade itself (Patent Document 1), A bevel gear cutter is known in which the tool life of the cutter is improved by applying a hard film coating to each blade portion (Patent Document 2).
The microfilm of the actual application No. 57-159122 (No. 59-62924) (page 13, FIGS. 4-7) JP 2001-353622 A (paragraph number 0017, FIG. 1, etc.)

By the way, each blade of the prior art is made of high speed steel (high speed). This is because it is possible to create a tooth profile and to make it cheaper than various tool materials such as diamond, CBN and cemented carbide.
However, considering that a plurality of blades are required for the cutter body, if the high speed blade and the blade are configured integrally as in the prior art, the entire blade can be replaced at the time of blade replacement. There is a problem that the running cost becomes expensive.

  High speed steel is softer than cemented carbide. In other words, in this integrated blade, the cutting speed must be set in consideration of the durability of the tool. That is, in the high speed, the application range of the cutting speed is as slow as about 20 to 150 m / min, which causes a problem that the working efficiency cannot be increased. Further, cutting using a high speed blade requires a separate water-soluble cutting fluid, which also leads to a problem that the running cost becomes expensive.

Thus, in the said prior art, the subject still remains about the point of the running cost required for the process of a gearwheel.
This invention is made | formed in view of such a subject, and it aims at providing the bevel gear cutter which can hold down the running cost of tooth profile creation inexpensively.

In order to achieve the above object, a bevel gear cutter according to claim 1 includes a cutter body having a rotation axis and a plurality of blades arranged at predetermined intervals in a circumferential direction of the cutter body. In the bevel gear cutter, the blade includes a blade portion that processes a tooth gap and a tooth bottom of the tooth profile, and an attachment concave portion to which the blade portion is detachably attached.
Further, the invention according to claim 2 is characterized in that the blade portion is attached to the attachment recess in the radial direction of the cutter body.

Further, the invention according to claim 3 is characterized in that the blade portion is made of cemented carbide.
Moreover, in invention of Claim 4, the blade part which processes one side of a tooth base and the blade part which processes the other side of a tooth base among tooth roots of a tooth profile are comprised separately. It is a feature.

Therefore, according to the bevel gear cutter of the present invention described in claim 1, since each blade of the bevel gear cutter is configured with a detachable blade portion, it is not necessary to replace the blade itself if only the blade portion is replaced. The running cost required for gear processing can be kept low.
According to the second aspect of the invention, since the blade portion is configured to be attachable to the mounting recess in the radial direction of the cutter body, not in the circumferential direction of the cutter body, the blade portion can be easily replaced. Thus, work efficiency can be improved.

Furthermore, according to the invention described in claim 3, it is possible to set a large cutting speed by using a cemented carbide blade part, and it is possible to achieve an improvement in processing efficiency as compared with the prior art, No cutting fluid is required, and the running cost can be further reduced.
Furthermore, according to the invention of claim 4, if the tooth bottom of the gear is divided and processed, the burden on the blade portion for processing the tooth bottom is reduced as compared with the conventional case, and the tool life can be extended. it can. Furthermore, it is possible to improve the processing accuracy of the boundary portion between the tooth bottom and the tooth gap.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The bevel gear cutter of this embodiment is shown in FIGS. 1 and 2, and the cutter 1 is used for generating a tooth profile of a bent tooth having a curved tooth surface such as a bent bevel gear or a hypoid gear.
The cutter 1 has a circular cutter body 2 having a rotation axis O, and the cutter body 2 has an inner peripheral surface 4 and an outer peripheral surface 6. Four cutter fixing holes 8 are arranged at predetermined positions in the vicinity of the inner peripheral surface 4 with a predetermined interval. The cutter fixing holes 8 have a small diameter from the main body front surface 3 toward the main body rear surface 5. It is formed in a stepped hole.

  On the other hand, a plurality of blades are arranged on the outer peripheral surface 6. Specifically, four blades 10, 20, 30, 40 are configured as one set, and the cutter body 2 of the present embodiment has a total of 24 blades of 6 sets with a predetermined equal interval. Are arranged. Each of these blades 10, 20, 30, and 40 shares and cuts the tooth gap of the tooth profile and the tooth bottom of the tooth profile. Each blade 10, 20, 30, 40 is disposed in a direction parallel to the rotation axis passing through the rotation axis O. Further, one tip (blade part) 16, 26, 36, 46 is provided at an appropriate position on the tip side of each blade 10, 20, 30, 40. On the other hand, each blade 10, 20, 30, 40 is fixed to the cutter body 2 by inserting the blade fixing bolt 51 from the outer peripheral surface 6 toward the rotation axis O.

  Then, the cutter 1 to which the blades 10, 20, 30, 40 are attached has the main body rear surface 5 directed to a gear machining device (not shown), the inner peripheral surface 4 engaged with the main shaft of the gear machining device, The gear is fixed to the gear machining device by being inserted into the cutter fixing hole 8. The main shaft of this gear machining apparatus is configured to be coaxial with the rotation axis passing through the rotation axis O. On the other hand, the work material (workpiece) is attached to the work shaft of the gear machining apparatus. The workpiece axis and the main axis are arranged so as to intersect with each other at a predetermined angle.

  Here, when the cutter 1 is rotated in the rotation direction T and the workpiece is advanced toward the cutter 1, the chips 16, 26, 36, and 46 come into contact with the workpiece, and cutting of the bent teeth is performed. When the desired workpiece feed amount is reached, the workpiece is moved backward. Next, after the workpiece shaft is rotated by one pitch and then the workpiece is advanced again toward the cutter 1, cutting of the adjacent bent teeth is performed. Thereafter, this operation is repeated until a desired tooth profile is created.

  The tip 16 is attached to the blade 10 and is a blade portion that processes the inner (one side) tooth bottom of the tooth bottom. This inner tooth bottom is a tooth bottom portion located on the side closer to the rotation axis O of the cutter body 2 in the radial direction. Moreover, the chip | tip 26 is attached to the braid | blade 20, and is a blade part which processes an inner tooth space among tooth-shaped tooth spaces. The inner tooth groove is a tooth groove portion located on the side closer to the rotation axis O in the radial direction.

  Further, the tip 36 is attached to the blade 30. The tip 36 is a blade portion that processes the outer (other side) tooth bottom of the tooth bottom of the tooth profile. This outer tooth bottom is a tooth bottom portion located on the far side in the radial direction from the rotation axis O. Further, the tip 46 is attached to the blade 40 and is a blade portion that processes an outer tooth groove among the tooth grooves of the tooth profile. This outer tooth space is a tooth space portion located on the far side in the radial direction from the rotation axis O. As described above, the tip according to the present embodiment is configured by dividing the bottom blade that is responsible for machining the tooth bottom into the inner bottom blade (bottom inner blade) and the outer bottom blade (bottom outer blade). Then, the tooth profile of the bent tooth is processed in the order of the inner tooth bottom, the inner tooth groove, the outer tooth bottom, and the outer tooth groove.

Details of the blade 10 are shown in FIG. This blade 10 is a blade for an inner bottom blade in charge of processing of the inner tooth bottom. The blade 10 is configured by placing a chip 16 with a bottom inner blade made of cemented carbide on a holder 11 made of carbon steel.
The holder 11 extends along a rotation axis passing through the rotation axis O of the cutter body 2, and is provided with an insertion hole 12 through which the blade fixing bolt 51 is inserted at an appropriate position in the longitudinal direction. Further, a tip mounting recess (mounting recess) 13 that opens toward the rotation axis O and the rotation direction T is formed on the tip end side of the holder 11. The chip mounting recess 13 includes a back surface support portion 14B that contacts the back surface of the chip 16, a lower surface support portion 14U that contacts the lower surface of the chip 16, and a side surface support portion 14S that contacts the side surface of the chip 16. . Further, a screw hole 15 to be screwed into the clamp screw 52 is formed at a substantially central portion of the back support portion 14B.

  The tip 16 is formed in a substantially flat plate shape, and a receiving hole 17 for receiving the clamp screw 52 is formed in a substantially central portion of the flat plate surface portion 18P. Further, an inner bottom edge 19 is formed at a corner portion that is continuous with the flat plate surface portion 18P in the vertical direction, and a work front surface 18F is formed at a substantially parallelogram-shaped portion that is continuous with the flat plate surface portion 18P in the horizontal direction. The chip 16 is subjected to a Ti (Al) N coating process.

Furthermore, the chip 16 of this embodiment is formed with rotational symmetry. That is, when the clamp screw 52 is removed from the arrangement of the tip 16 shown in FIG. 5A, the bottom inner blade edge 19 is brought close to the lower surface support portion 14U, and the flat plate surface portion 18P is brought into contact with the rear surface support portion 14B, The part located on the opposite side of the bottom inner edge 19 with respect to the center of gravity is configured to be the edge.
The clamp screw 52 is inserted into the receiving hole 17 from the radial direction of the cutter body 2, in other words, from the normal direction of the rotation direction T of the cutter body 2, not from the direction facing the workpiece front surface 18 </ b> F. The chip 16 is detachably attached to the chip mounting recess 13 by detaching the clamp screw 52.

Next, details of the blade 20 are shown in FIG. This blade 20 is a blade for an inner blade that is in charge of machining the inner tooth gap. The blade 20 is also configured by placing a chip 26 with an inner blade made of cemented carbide on a holder 21 made of carbon steel.
The holder 21 is also provided with an insertion hole 22 that is inserted into the blade fixing bolt 51 at an appropriate position in the longitudinal direction, and a tip that opens toward the rotation axis O and the rotation direction T on the tip side of the holder 21. An attachment recess (attachment recess) 23 is formed. The chip mounting recess 23 also includes a back surface support portion 24B, a bottom surface support portion 24U, and a side surface support portion 24S, which are in contact with each surface of the chip 26. A screw hole 25 to be screwed into the clamp screw 52 is formed in a substantially central portion of the back support portion 24B.

  The tip 26 is also subjected to a Ti (Al) N coating process and is formed in a substantially flat plate shape. A receiving hole 27 for receiving the clamp screw 52 is formed in a substantially central portion of the flat plate surface portion 28P. Further, an inner blade ridge 29 is formed at a corner portion that is continuous with the flat plate surface portion 28P in the vertical direction, and a work front surface 28F is formed at a substantially parallelogram-shaped portion that is continuous with the flat plate surface portion 28P in the horizontal direction.

  Further, the chip 26 of the present embodiment is also formed with rotational symmetry. That is, when the inner blade ridge 29 is brought closer to the lower surface support portion 24U from the position shown in FIG. 5A, the portion located on the opposite side of the inner blade ridge 29 via the flat plate surface portion 28P becomes the blade ridge, and then the flat plate When the surface portion 28P is brought into contact with the back surface support portion 24B, a portion located on the opposite side of the flat plate surface portion 28P appears on the front side, and a portion located on the opposite side of the inner blade ridge 29 with respect to the center of gravity becomes the blade ridge. On the other hand, when the flat plate surface portion 28P is brought into contact with the back support portion 24B from the position shown in FIG. 5A, the adjacent corner portion of the inner blade edge 29 is configured to be a blade edge. Therefore, four inner blade edges 29 are formed on the tip 26. The total length L2 of the blade 20 provided with the tip 26 is configured to be shorter than the total length L1 of the blade 10 provided with the tip 16.

The clamp screw 52 is inserted from the normal direction of the rotation direction T of the cutter body 2, and the chip 26 is detachably attached to the chip attachment recess 23 by detaching the clamp screw 52.
The details of the blade 30 are shown in FIG. The blade 30 is a bottom outer blade in charge of processing the outer tooth bottom. The blade 30 is also configured by placing a tip 36 with a bottom outer blade made of cemented carbide on a holder 31 made of carbon steel.

  The holder 31 is also provided with an insertion hole 32 inserted into the blade fixing bolt 51 at an appropriate position in the longitudinal direction. The holder 31 has a distal end side opposite to the rotation axis O and in the rotation direction T. A chip mounting recess (mounting recess) 33 is formed. The chip mounting recess 33 includes a back support part 34B, a bottom support part 34U, and a side support part 34S, which are in contact with each surface of the chip 36. Note that a screwing hole 35 to be screwed into the clamp screw 52 is formed in a substantially central portion of the back support part 34B.

  The tip 36 is also subjected to a Ti (Al) N coating process and is formed in a substantially flat plate shape. A receiving hole 37 for receiving the clamp screw 52 is formed in a substantially central portion of the flat plate surface portion 38P. Further, a bottom outer blade ridge 39 is formed at a corner portion that is continuous with the flat plate surface portion 38P in the vertical direction, and a workpiece front surface 38F is formed at a substantially parallelogram-shaped portion that is continuous with the flat plate surface portion 38P in the horizontal direction.

  Regarding the rotational symmetry of the tip 36 of the present embodiment, the bottom outer blade edge 39 is brought close to the lower surface support portion 34U from the position shown in FIG. 5A, and the flat plate surface portion 38P is brought into contact with the rear surface support portion 34B. The portion located on the opposite side of the bottom outer blade ridge 39 with respect to the center of gravity is the blade ridge. The total length L3 of the blade 30 provided with the tip 36 is configured to be equal to the total length L1 of the blade 10 provided with the tip 16.

Then, the clamp screw 52 is inserted into the tip 36 from the normal direction of the rotation direction T of the cutter body 2, and the tip 36 is detachably attached to the tip mounting recess 33 by the removal of the clamp screw 52.
Further details of the blade 40 are shown in FIG. This blade 40 is a blade for outer blades in charge of processing of the outer tooth gap. The blade 40 is also configured by placing a chip 46 with an outer blade made of cemented carbide on a holder 41 made of carbon steel.

  The holder 41 is also provided with an insertion hole 42 through which the blade fixing bolt 51 is inserted at an appropriate position in the longitudinal direction. The holder 41 has a distal end side opposite to the rotation axis O and in the rotation direction T. A chip mounting concave portion (mounting concave portion) 43 that opens toward the surface is formed. The chip mounting recess 43 includes a back surface support portion 44 </ b> B, a bottom surface support portion 44 </ b> U, and a side surface support portion 44 </ b> S, which are in contact with each surface of the chip 46. Note that a screwing hole 45 to be screwed into the clamp screw 52 is formed in a substantially central portion of the back support part 44B.

  The tip 46 is also subjected to a Ti (Al) N coating process. The tip 46 is formed in a substantially flat plate shape, and a receiving hole 47 for receiving the clamp screw 52 is formed in a substantially central portion of the flat plate surface portion 48P. Further, an outer edge ridge 49 is formed at a corner portion that is continuous with the flat plate surface portion 48P in the vertical direction, and a workpiece front surface 48F is formed at a substantially parallelogram-shaped portion that is continuous with the flat plate surface portion 48P in the horizontal direction.

  Regarding the rotational symmetry of the tip 46 of the present embodiment, when the outer blade edge 49 is brought close to the lower surface support portion 44U from the position shown in FIG. The position is the edge of the blade. Next, when the flat plate surface portion 28P is brought into contact with the back surface support portion 44B, the portion located on the opposite side of the outer blade ridge 49 with respect to the center of gravity becomes the blade ridge. Further, when the flat plate surface portion 28P is brought into contact with the back support portion 44B from the position shown in FIG. 5A, the adjacent corner portion of the outer blade ridge 49 becomes the blade ridge. That is, four outer blade edges 49 are formed on the tip 46. The total length L4 of the blade 40 including the tip 46 is configured to be equal to the total length L2 of the blade 20 including the tip 26.

Then, the clamp screw 52 is inserted into the tip 46 from the normal direction of the rotation direction T of the cutter body 2, and the tip 46 is detachably attached to the tip mounting recess 43 by detachment of the clamp screw 52.
Thus, according to the bevel gear cutter 1 of the present embodiment, the chips 16, 26, 36, 46 can be detachably attached to the blades 10, 20, 30, 40, and the chips 16, 26 are detachable. , 36, and 46 are replaced, the holders 11, 21, 31, 41 themselves need not be replaced. Therefore, the running cost required for processing the gear can be suppressed at a lower cost than in the past.

Moreover, since each chip | tip 16,26,36,46 is formed with the cemented carbide, the cutting speed can be set large. Specifically, the application range of the cutting speed in this case is as fast as about 50 to 300 m / min, and the machining efficiency is improved as compared with the conventional case. In addition, in this case, the cutting fluid is not necessary, so that the running cost can be further reduced.
Further, each chip 16, 26, 36, 46 is not a workpiece front face 18F, 28F, 38F, 48F, but from a flat plate surface part 18P, 28P, 38P, 48P, in other words, a chip mounting recess in the radial direction of the cutter body 2. 13, 23, 33, 43 can be attached. Therefore, the replacement work of each of the chips 16, 26, 36, 46 becomes easier and the work efficiency is improved, and moreover, the chips 16, 26, Damage to 36 and 46 can be prevented.

Since the processing of the tooth bottom is performed separately for the tip 16 with the bottom inner blade and the tip 36 with the bottom outer blade, the burden on the bottom blade edge is reduced as compared with the case of performing with a single bottom blade as in the prior art. The tool life can be extended.
Furthermore, if the chip 16 and the chip 36 are divided, the processing accuracy at the boundary between the tooth bottom and the tooth gap is improved. FIG. 7 shows the creation of a tooth profile by the cutter 1. The bent tooth profile 60 cut by the cutter 1 includes an inner tooth bottom 63 (FIG. (A)), an inner tooth groove 61 (FIG. (B)), an outer tooth base 64 (FIG. (C)), The outer tooth spaces 62 (FIG. (D)) are processed in this order.

  Here, as shown in FIG. 5A, when the bottom inner edge 19 of the tip 16 cuts the inner tooth bottom 63, the flat plate surface portion 18P of the tip 16 is in contact with the formation surface of the inner tooth groove 61. Rather than being parallel, they are arranged with a predetermined angle α with respect to the formation surface of the tooth gap 61. The tip 16 cuts a part of the inner tooth gap 61 connected to the tooth bottom 63 in addition to the inner tooth root 63. In this way, by cutting with the edge of the same tip not only from the tooth bottom 63 but from the tooth bottom 63 to the tooth groove 61, the corner portions of the tooth bottom 63 and the tooth groove 61 are also processed with the same accuracy, Burrs and cracks are less likely to occur at the corners.

After the inner tooth bottom 63 is processed, the inner blade edge 29 of the tip 26 processes the inner tooth gap 61. As shown in FIG. 5B, the flat plate surface portion 28P of the chip 26 is arranged along the formation surface of the inner tooth groove 61.
After processing the inner tooth space 61, the bottom outer edge 39 of the tip 36 processes the outer tooth base 64. In this case, as shown in FIG. 5C, when the bottom outer edge ridge 39 of the tip 36 cuts the outer tooth bottom 64, the flat plate surface portion 38P of the tip 36 is in contact with the formation surface of the outer tooth groove 62. Are arranged with a predetermined angle α. The tip 36 is cut with the edge of the same tip not only from the root 64 but also from the root 64 to the tooth gap 62. Therefore, the corner portion of the tooth root 64 and the tooth groove 62 is processed with the same accuracy as the tooth bottom 64, and burrs and cracks are less likely to occur in the corner portion.

After the outer tooth bottom 64 is processed, the outer blade edge 49 of the tip 46 processes the outer tooth groove 62. As shown in FIG. 4D, the flat plate surface portion 48P of the chip 46 is disposed along the formation surface of the outer tooth groove 62.
The description of one embodiment of the present invention is finished above, but the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above-described embodiment, 24 blades of 6 sets are attached to the cutter body, but the present invention is not necessarily limited to this form. It can be changed as appropriate according to the material type of the workpiece, and in this case as well, the effect of keeping the running cost of tooth profile creation low can be achieved as described above.

It is a front view of the bevel gear cutter concerning one embodiment of the present invention. It is the II-II sectional view taken on the line of FIG. FIG. 2 is a front view and a left side view of the bottom inner blade and the tip of FIG. 1. It is the front view and left view of the blade for inner blades and a chip | tip of FIG. FIG. 2 is a front view and a right side view of the bottom outer blade and the tip of FIG. 1. It is the front view and right view of the blade for outer blades and a chip | tip of FIG. It is a figure which shows creation of the tooth profile by the bevel gear cutter of FIG.

Explanation of symbols

1 Bevel gear cutter 2 Cutter body 10 Blade for bottom inner blade (blade)
13 Chip mounting recess (Mounting recess)
16 Tip with bottom inner blade (blade)
20 Blade for inner blade (blade)
23 Chip mounting recess (Mounting recess)
26 Tip with inner blade (blade)
30 Blade for bottom outer blade (blade)
33 Chip mounting recess (Mounting recess)
36 Tip with bottom outer blade (blade)
40 Blade for outer blade (blade)
43 Chip mounting recess (Mounting recess)
46 Tip with outer blade (blade)
52 Clamp screw

Claims (4)

A cutter body with a rotation axis;
A bevel gear cutter including a plurality of blades arranged at predetermined intervals in a circumferential direction of the cutter body,
The blade is
A blade for machining the tooth gap and root of the tooth profile;
A bevel gear cutter, comprising: an attachment recess to which the blade portion is detachably attached.   The bevel gear cutter according to claim 1, wherein the blade portion is attached to the attachment recess in a radial direction of the cutter body.   The bevel gear cutter according to claim 1 or 2, wherein the blade portion is made of cemented carbide.   The blade part that processes one side of the tooth bottom and the blade part that processes the other side of the tooth bottom among the tooth bottoms of the tooth profile are configured separately and independently. The bevel gear cutter according to any one of the above.

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