JPH09248765A - Device for highly strengthening toothed wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely improve surface roughness and fatigue strength and surely remove fine glass bead chips by providing a mechanism for jetting out fluid of glass beads and liquid onto the surface of toothed wheel after heat treatment and a mechanism for suctionwise recovering the used fluid, the recovering mechanism having a suction port in a chamber. SOLUTION: In a high strengthening device 10, first a toothed wheel 12 subjected to the tooth forming work is subjected to carbonization quenching and set on a spindle 42, and rotated and moved to the direction of arrow XI. In this case, a jetting out mechanism 24 is driven so that glass beads 20 in a pipe line 90 is mixed with water 18 and the mixture is jetted out to a toothed wheel 12 from a nozzle 72. The surface of the toothed wheel is thereby given with compression remaining stress through the glass beads 20 and the polishing work is applied thereto, thereby surely forming the smooth surface. The water 18 and the glass beads 20 jetted into the chamber 14a and crushed are discharged into a conveyer for discharge liquid 100 from a conical part 98 of casing 14 and are recovered in the outside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear strength increasing device for increasing the strength of a gear surface.

[0002]

2. Description of the Related Art Normally, a gear is repeatedly subjected to a load during use, and it is necessary to increase the fatigue strength of the gear surface. Therefore, hitherto, shot peening has been widely performed in which a steel ball or the like is collided with the gear surface to give a compressive residual stress.

However, in shot peening, since the steel balls are used as the shot material, the gear surface is roughened, and the surface roughness is lowered. Therefore, as disclosed in Japanese Patent Publication No. 5-21711, the surface of a metal molded product is quenched, and then the metal surface is ground, and then glass beads having a particle diameter of 0.2 mm to 0.6 mm are projected. There is known a method for increasing the strength of a metal surface. This is intended to improve the fatigue strength without roughening the metal surface.

[0004]

However, in the above-mentioned prior art, the compressive residual stress applied is lowered and the fatigue strength cannot be improved to a desired value, and the directivity of the projected glass beads is also increased. Therefore, it has been pointed out that the glass beads are scattered in various directions and the efficiency is remarkably lowered due to the poor quality.

Further, since the glass beads collide with the surface of the gear, which is a metal surface, and are crushed, glass bead scraps of micron order (hereinafter also referred to as powder scraps) are suspended in the processing chamber. However, the gear that is the object to be processed is mounted on the spindle and is rotated at a high speed, and fine powder debris easily adheres to the spindle that rotates at a high speed, which causes a problem such as poor rotation of the spindle. Has been pointed out.

The present invention solves this kind of problem and improves the surface roughness and the fatigue strength without fail, and enhances the strength of a gear capable of reliably removing fine glass bead scraps. The purpose is to provide a device.

[0007]

According to the present invention, in order to solve the above-mentioned problems, a jet of liquid and glass beads is projected from a jet mechanism toward a gear surface after heat treatment in a chamber. Therefore, the glass beads collide with the gear surface accurately with directivity, and a desired compressive residual stress is applied to the gear surface, and the glass beads are crushed to polish the gear surface. To be done.

At this time, fine powder debris is generated by crushing the glass beads, and the powder debris is surely sucked from the suction port which is located near the gear and faces the chamber. Here, by having the first and second suction ports arranged so as to sandwich the gear and the nozzle, the work of collecting and removing dust and debris can be performed more reliably, and the gear and the nozzle can be sandwiched from four sides. By having the first to fourth suction ports arranged in, the collection efficiency of the powder dust is further improved. As a result, it is possible to effectively prevent the powder dust from adhering to the spindle or the like.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a partial cross-sectional front view of a strengthening apparatus 10 according to a first embodiment of the present invention.
FIG. 2 is a partial cross-sectional side view illustration of the strength-enhancing device 10.

The apparatus 10 for strengthening strength holds a gear 12 which is an object to be processed, and a chamber (processing chamber) in a casing 14.
A gear holding mechanism 16 for positioning and holding the gear 12 by 14a, and a projection mechanism 2 for projecting a jet flow 22 of liquid, for example, water 18 and glass beads 20, toward the gear 12.
4, a water supply mechanism 26 for pumping the water 18 to the projection mechanism 24, and the glass beads 20 to the projection mechanism 24.
And a mist collecting mechanism 3 for sucking and collecting powder dust 20b generated by crushing the glass beads 20 on the surface of the gear 12 by a predetermined amount.
1 is provided.

The gear holding mechanism 16 is, as shown in FIG.
An X-axis slide unit 30 and a spindle unit 32 mounted on the base 29 are provided. The X-axis motor 34 constituting the X-axis slide unit 30 is attached to the ball screw 36.
And the pair of guide bars 3 are connected to the ball screw 36.
8 are arranged in parallel, and the spindle unit 32 is provided via the ball screw 36 and the guide bar 38.
Are supported so that they can move back and forth in the direction of arrow X.

The spindle unit 32 has a spindle 42 connected to a spindle motor 40, and the gear 12 is mounted on the tip of the spindle 42. The tip end side of the spindle unit 32 has a side portion 14 b of the casing 14.
It can be inserted into the casing 14 through the opening 44 formed in the.

As shown in FIG. 2, the projection mechanism 24 comprises a Y-axis slide unit 46 and a Z-axis slide unit 48. The Y-axis slide unit 46 has a Y-axis motor 50 oriented in the horizontal direction, and via a ball screw 52 connected to the Y-axis motor 50 and a pair of guide bars 54 parallel to the ball screw 52, The Z-axis slide unit 48 can move back and forth in the arrow Y direction. The moving body 62 is moved in the arrow Z direction via a ball screw 58 extending vertically downward from the Z-axis motor 56 forming the Z-axis slide unit 48 and a pair of guide bars 60 parallel to the ball screw 58. You can move back and forth freely.

A tube body 66 is attached to the tips of a pair of support rods 64 extending from the moving body 62 in the arrow Y direction and oriented in the arrow Z direction. An opening / closing valve 68 for turning on / off the introduction of the water 18 is provided at an upper portion of the pipe body 66, and a mixing chamber for mixing the glass beads 20 with the water 18 is provided at a lower portion of the pipe body 66. 70 is connected to the bottom of the mixing chamber 70.
2 are provided.

The water supply mechanism 26 has a water pipe line 74 connected to the inlet side of the opening / closing valve 68. The water pipe line 74 is spirally wound inside the casing 14 and then is provided outside the casing 14. It is connected via a joint 76 (see FIG. 1). A high pressure pump (not shown) is connected to the joint 76, and the high pressure pump is set to project the jet flow 22 toward the gear 12 at a predetermined injection pressure.

The glass bead supply mechanism 28 includes a hopper 80 which is held on the upper surface of the casing 14 via a mounting base 78. A load cell 82 for detecting the remaining amount of the glass beads 20 in the hopper 80 is arranged below the hopper 80. As shown in FIG. 1, on the outlet side of the hopper 80, a metering valve 84, a negative pressure meter 86, and a laser flow meter 88 are connected in a vertically downward direction. One end of the conduit 90 is connected to the laser flow meter 88, and the other end is inserted into the chamber 14 a in the casing 14 and connected to the mixing chamber 70. The diameter of the glass beads 20 filled in the hopper 80 is set to 0.05 mm to 0.3 mm.

The mist collecting mechanism 31 has a main body 31a mounted on the base 29. A pair of ducts 94 and 96 are connected to communicate with a negative pressure generation source (not shown) housed in the main body 31a.
The front end portion of is inserted into the chamber 14a from the side portion 14b of the casing 14. The first and second openings 94a, 96a formed at the tip of the pair of ducts 94, 96 are
An opening is formed between the gear 12 and the nozzle 72 and close to the gear 12 (see FIG. 2).

On the lower side of the casing 14, there is integrally provided a conical portion 98 which is directed downward and has a reduced diameter. Below the lower opening of the conical portion 98, a drainage conveyor 100 is provided. It is arranged.

The operation of the strengthening device 10 thus constructed will be described below.

First, the gear 12 which has been subjected to gear cutting by cutting is carburized and quenched. And
The gear 12 after the carburizing and quenching treatment is set on the spindle 42 that constitutes the gear holding mechanism 16, while the projection mechanism 24
The nozzle 72 constituting the above is selectively position-adjusted in the arrow Y direction and the arrow Z direction via the Y-axis slide unit 46 and the Z-axis slide unit 48, and is arranged corresponding to the gear 12.

Therefore, the gear 12 rotates in a predetermined direction integrally with the spindle 42 via the spindle motor 40, and the gear 12 is rotated by the spindle unit 32 via the X-axis motor 34 constituting the X-axis slide unit 30. And moves in the direction of arrow X1 integrally with (see FIG. 1).

At this time, the projection mechanism 24 is driven, and the water 18 is pressure-fed from the pipe 66 to the mixing chamber 70 via the water pipe 74 under the action of a high-pressure pump (not shown). On the other hand, the metering valve 8 constituting the glass bead supply mechanism 28
4 is driven, and a predetermined amount of glass beads 20 are fed to the mixing chamber 70 from the conduit 90. Therefore, when the water 18 is jetted from the nozzle 72, a negative pressure is generated in the mixing chamber 70, and the glass beads 20 in the pipe line 90 mix with the water 18 to form a jet flow 22 from the nozzle 72. It is projected on the gear 12.

Therefore, the jet flow 22 of the water 18 and the glass beads 20 has directivity, and the tooth tip 102 of the gear 12 and the tooth surface 1 are directed.
04 and the desired position of the root 106 are accurately collided (see FIGS. 3A to 3C).

Further, as shown in FIG. 4, when the glass beads 20 collide with the tooth surface 104 of the gear 12, this tooth surface 1
The surface of No. 04 is given a compressive residual stress via the glass beads 20 and is polished, and the glass beads 20 are crushed. At that time, the crushed pieces 20a are
The water 18 jetted toward the tooth surface 104 presses the surface of the tooth surface 104 at an acute angle. Therefore, the gear 12 has an effect that the tooth surface 104 to the tooth root 106 are subjected to the polishing treatment and are surely processed into a smooth surface.

5A shows an enlarged view of the tooth flank 104 after the carburizing and quenching treatment of the gear 12, and FIG. 5B shows
An enlarged view of the tooth flank 104 after the gear 12 has been strengthened by the strengthening device 10 is shown. FIG. 6A is an enlarged view of the tooth root after the carburizing and quenching treatment.
B shows an enlarged view of the tooth bottom subjected to the strengthening treatment by the strengthening device 10. As a result, the surface of the tooth surface 104 and the tooth bottom were smoothed while the oxide layer was effectively removed by the strengthening treatment.

By the way, the water 18 and the crushed pieces 20a of the glass beads 20 jetted into the chamber 14a are discharged from the conical portion 98 provided in the lower portion of the casing 14 into the drainage conveyor 100, and this drained liquid is discharged. It is collected outside via the conveyor 100. However, fine powder debris 2 produced by crushing the glass beads 20
0b (see FIG. 4) easily floats in the chamber 14a.

Here, in the first embodiment, the tip end portions of the pair of ducts 94 and 96 forming the mist collecting mechanism 31 are inserted into the chamber 14a, and the first and second tip end portions are formed at the respective tip portions. The openings 94a and 96a have the gear 1
An opening is formed between the nozzle 2 and the nozzle 72 and close to the gear 12. Therefore, when the mist collecting mechanism 31 is driven and suction is performed from the first and second openings 94a and 96a, as shown in FIG. 7, a fine powder flow that floats in the chamber 14a close to the gear 12 is obtained. The mist containing the dust 20b is reliably sucked from the first and second openings 94a, 96a through the pair of ducts 94, 96.

As a result, the powder dust 20b produced by crushing the glass beads 20 is easily and surely collected by the mist collecting mechanism 31, and the powder dust 20b does not adhere to the spindle 42 or the like. So, for example,
The powder dust 20b adheres to the spindle 42 that rotates at a high speed,
The effect that it is possible to prevent the occurrence of a defect in the rotation operation of the spindle 42 is obtained.

Next, FIGS. 8 and 9 show a strengthening apparatus 200 according to the second embodiment. The same components as those of the strength enhancing device 10 according to the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The strength-enhancing device 200 comprises a casing 201 which is set to have a necessary minimum width dimension in which the projection mechanism 24 can be housed, and a mist collecting mechanism 202. From the negative pressure generation source (not shown) constituting the mist collecting mechanism 202, four ducts 204, 206, 208 and 210 are provided.
Extends.

The tip portions of the ducts 204 and 206 are provided from one side portion 201b of the casing 201 to the chamber 201a.
First and second openings 204 a and 206 a that are inserted into the inside and are formed at the respective tips are opened between the gear 12 and the nozzle 72 and close to the gear 12. The tip portions of the ducts 208 and 210 have the casing 20.
The third and fourth openings 208a and 210a, which are inserted into the chamber 201a from the other side portion 201c of No. 1 and are formed at the respective tip portions, are provided between the gear 12 and the nozzle 72 and close to the gear 12. And it is open.

Strengthening device 200 having such a structure
Then, when the jet flow 22 is projected from the projection mechanism 24 to the gear 12 and the gear 12 rotates and moves in the axial direction to perform the strengthening treatment on the gear 12, the mist recovery mechanism 202 Driven.

For this reason, the first to fourth openings 204a, 206a, 208a and 2 which are opened close to the gear 12 are provided.
The mist that is sucked from 10a and includes the fine powder debris 20b that is in proximity to the gear 12 and floats in the chamber 201a is the first to fourth openings 204a, 206a, 2 and 2.
Four ducts 204, 20 from 08a and 210a
Aspirated via 6, 208 and 210. Therefore,
An advantage that the suction and collection work of the powder dust 20b can be performed more reliably and efficiently is obtained.

[0034]

As described above, in the gear strengthening device according to the present invention, since the jet of liquid and glass beads is projected toward the gear surface after heat treatment, the glass beads have a directivity. It has an accurate collision with the gear surface. Therefore, the desired compressive residual stress is applied to the gear surface, and the glass beads are crushed to polish the gear surface.

At this time, fine powder dust is generated by crushing the glass beads, and the mist containing the powder dust is surely sucked from the suction port that is located near the gear and faces the chamber. It As a result, it is possible to effectively prevent the powder debris floating in the chamber from adhering to the drive unit such as the spindle.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional front view of a strengthening device according to a first embodiment of the present invention.

FIG. 2 is a side view of a partial cross section of the strengthening device according to the first embodiment.

FIG. 3 is a diagram for explaining the operation of the strength-enhancing device,
3A is an explanatory diagram of a tooth tip processing state, FIG. 3B is an explanatory diagram of a tooth surface processing state, and FIG. 3C is an explanatory diagram of a tooth root processing state.

FIG. 4 is an explanatory diagram when glass beads collide with a tooth surface.

5A and 5B are operation explanatory views of the strengthening device, and FIG.
FIG. 5B is an enlarged view of a portion corresponding to the reference pitch circle after the carburizing and quenching treatment, and FIG. 5B is an enlarged view of the portion corresponding to the reference pitch circle subjected to the strengthening treatment.

6A and 6B are operation explanatory views of the strengthening device, and FIG.
FIG. 6B is an enlarged view of the tooth root after the carburizing and quenching treatment.
[Fig. 4] is an enlarged view of the tooth root after the strengthening treatment.

FIG. 7 is a partially enlarged view of the strengthening device for explaining the operation of the mist collecting mechanism.

FIG. 8 is a partial cross-sectional front view of the strengthening device according to the second embodiment of the present invention.

FIG. 9 is an enlarged side view of an essential part of the strength-enhancing device according to the second embodiment.

[Explanation of symbols]

10, 200 ... Strengthening device 12 ... Gears 14, 201 ... Casing 14a, 201a
... Chamber 16 ... Gear holding mechanism 18 ... Water 20 ... Glass beads 22 ... Jet flow 24 ... Projection mechanism 26 ... Water supply mechanism 28 ... Glass bead supply mechanism 31, 202 ... Mist collecting mechanism 66 ... Pipe 72 ... Nozzle 74 ... Water pipe 80 ... Hopper 90 ... Pipeline 94, 96, 204, 206, 208, 210 ... Duct 94a, 96a, 204a, 206a, 208a, 21
0a ... opening

Claims (3)

[Claims] 1. A gear strengthening device for increasing the strength of a gear surface, comprising a projection mechanism for projecting a jet of glass beads and a liquid from a nozzle toward the gear surface after heat treatment in a chamber. And a collecting mechanism for sucking and collecting the powder debris generated by crushing the glass beads on the surface of the gear, and the collecting mechanism is arranged in the vicinity of the gear and faces the chamber. An apparatus for strengthening a gear, which has a suction port. 2. The high strength apparatus according to claim 1, wherein the suction port has first and second suction ports arranged so as to sandwich the gear and the nozzle. Strengthening device. 3. The strengthening device according to claim 1, wherein the suction port has first to fourth suction ports arranged so as to sandwich the gear and the nozzle from four sides. Strengthening device.