JPH09248762A - Strengthening device for gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately and reliably supply glass beads by the specified amount as well as to reliably improve surface roughness and fatigue strength. SOLUTION: A strengthening device is provided with a spouting mechanism 24 for spouting jets 22 of glass beads 20 and water 18 toward the front surface of a gear 12 which is heat treated, a glass beads supplying mechanism 28 for supplying the glass beads 20 to the spouting mechanism 24, and a water supplying mechanism 26 for supplying water 18 to the spouting mechanism 24. The glass beads supplying mechanism 28 is provided with a heater 81 for preventing glass beads 20 from being adhered to each other through moisture.

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 caused to collide with the gear surface after heat treatment 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, the glass beads are usually stored in a hopper, and the glass beads are sent by a predetermined amount through a pipe line connecting the hopper and the nozzle. However, since the glass beads have a small particle size, they tend to be clogged between the hopper and the nozzle due to moisture absorption. As a result, it has been pointed out that a prescribed amount of glass beads cannot be projected onto the surface of the gear and that the strength of the gear cannot be stably increased.

The present invention solves this kind of problem, and it surely improves the surface roughness and fatigue strength, and at the same time, the high strength of the gear that enables the glass beads to be accurately and reliably supplied in predetermined amounts. It is an object of the present invention to provide a chemical conversion device.

[0007]

In order to solve the above problems, the present invention supplies a liquid from a first supply mechanism to a projection mechanism and a glass bead to the projection mechanism from a second supply mechanism, The jet of liquid and glass beads is projected onto the gear surface. 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, the second supply mechanism has a glass bead drying means to prevent the glass beads from adhering to each other due to moisture. If the glass bead drying means is equipped with, for example, a heater attached to a hopper that stores the glass beads, the temperature inside the hopper can be maintained at a predetermined temperature to remove the moisture adhering to the glass beads. . Therefore, even if glass beads having a large amount of water absorption and a small particle size are used because the liquid is used, the glass beads are not clogged in the second supply mechanism, and a predetermined amount of the glass beads can be obtained from the second supply mechanism. Can be reliably supplied to the projection mechanism.

Further, the second supply mechanism has a tube body for allowing the glass beads to flow therethrough, and the amount of the glass beads flowing in the tube body is detected by the flow rate detection sensor. Therefore, the amount of glass beads actually supplied from the second supply mechanism toward the projection mechanism is accurately detected, and the stable supply of the glass beads is more reliably performed.

Furthermore, the pressure inside the pipe for circulating the glass beads is detected by the pressure sensor. Thereby, an abnormality such as a crack or detachment of the tubular body can be quickly detected.

[0011]

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

The device 10 for strengthening strength has a gear holding mechanism 16 for holding a gear 12 as an object to be processed and positioning and holding the gear 12 in a chamber 14a in a casing 14, a liquid such as water 18 and glass beads. 20 and a projection mechanism 24 for projecting a jet flow 22 toward the gear 12, and a water supply mechanism (first unit) for pumping the water 18 to the projection mechanism 24.
A supply mechanism) 26 and a glass bead supply mechanism (second supply mechanism) 28 that sends the glass beads 20 to the projection mechanism 24 by a predetermined amount.

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 can be inserted into the casing 14 through an opening 44 formed in the side wall of the casing 14.

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. On the outer periphery of the hopper 80, a band-shaped heater 81 is mounted as a glass bead drying means in order to prevent the glass beads 20 stored in the hopper 80 from adhering to each other due to water. 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 vertically oriented and connected. The conduit 90 is
One end thereof 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 glass beads 20 stored in the hopper 80 have a diameter of 0.05 mm or more.
It is set to 0.3 mm.

As shown in FIG. 3, the laser flow meter 88 is
Two transparent plates 112a and 112b such as glass plates are provided,
The transparent plates 112a and 112b form a predetermined gap 114 for allowing the glass beads 20 to pass therethrough, and are arranged to face each other. On one transparent plate 112a side,
The laser beam 1 is applied over the entire width of the transparent plate 112a.
A laser light source 116 for irradiating 16a is arranged, and the laser light 116 is provided on the other transparent plate 112b side.
A laser light receiving unit 118 is provided which irradiates the transmitted light of a.

A mist collecting mechanism 92 is placed on the base 29. The tip ends of the pair of ducts 94 and 96 that form the mist collecting mechanism 92 are inserted into the chamber 14a from the side of the casing 14 and are arranged between the gear 12 and the nozzle 72 and close to the gear 12. ing.

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.

Then, 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 the mixing chamber 7 is fed from the hopper 80.
A predetermined amount of glass beads 20 is fed to the container 0 through the pipe line 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. 4A to 4C).

Here, the module is 1.5 and the twist angle is 3
The jet 12 is projected at 18 ° to the portion corresponding to the reference pitch circle (PCD) of the tooth surface 104 by using the gear 12 set to 6 °, the pressure angle of 17.5 °, and the number of teeth of 52. As a result, the jet flow 22 can be reliably projected onto the tooth surface 104 and the tooth root 106 of the gear 12, and the tooth surface 104
And, it becomes possible to give a sufficient compressive residual stress to the root 106.

Further, as shown in FIG. 5, when the glass beads 20 collide with the tooth surface 104 of the gear 12, the 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 at least the portion corresponding to the reference pitch circle of the tooth surface 104 is subjected to the polishing process from the tooth root 106 to be surely processed into a smooth surface.

FIG. 6A is an enlarged view of the tooth surface 104 after the carburizing and quenching treatment of the gear 12, and FIG. 6B shows
An enlarged view of the tooth flank 104 after the gear 12 has been strengthened by the strengthening device 10 is shown. FIG. 7A is an enlarged view of the tooth bottom 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.

The jet 22 is projected from the nozzle 72 and the gear 1
When subjecting 2 to the strengthening treatment, crushed fine glass bead dust floats in the chamber 14a. Therefore, by driving the mist collecting mechanism 92, the chamber 14
A pair of ducts 9 for removing fine glass bead dust floating in a
It can be surely collected by suction from 4, 96. Further, the pieces of water 18 and the glass beads 20 jetted into the chamber 14 a are discharged into the drainage conveyor 100 from the conical portion 98 provided in the lower portion of the casing 14, and the drainage conveyor 100 is used. Be collected outside.

By the way, in this embodiment, a heater 81, which is a glass bead drying means, is attached to the outer periphery of the hopper 80 which constitutes the glass bead supply mechanism 28. The glass beads 20 stored in the hopper 80 are constantly maintained at a predetermined temperature, for example, 40 ° C. or higher under the action of the heater 81.

Therefore, the moisture adhering to the glass beads 20 is surely removed by moisture absorption, and the clogging of the glass beads 20 does not occur. This allows
In particular, the particle size is as small as 0.05 mm to 0.3 mm,
Fine glass beads 20 that are easily clogged due to moisture absorption
Even in this case, it is possible to obtain an effect that the hopper 80 can stably supply the projection mechanism 24 through the conduit 90.

Further, in the present embodiment, the metering valve 84
A laser flow meter 88 for detecting the amount of the glass beads 20 sent from the hopper 80 to the projection mechanism 24 side via the
It has. As shown in FIG. 3, when the glass beads 20 pass through the gap 114 between the transparent plates 112a and 112b, the laser flow meter 88 has a laser beam 116a extending from the laser light source 116 over the entire width of the transparent plates 112a and 112b. Irradiate. Then, this laser light 116
The passing amount of the glass beads 20 is measured by irradiating the laser light receiving portion 118 with a as transmitted light.

As a result, a predetermined amount of glass beads 20
However, there is an advantage that it is possible to accurately detect whether or not the glass beads 20 are actually supplied from the hopper 80 to the projection mechanism 24 side via the conduit 90, and the stable supply operation of the glass beads 20 can be performed more reliably.

Furthermore, in this embodiment, the conduit 90
Is connected to the laser flowmeter 88 at one end thereof, that is, the water 1 pumped to the projection mechanism 24 via the water conduit 74.
8, a negative pressure state is generated in the mixing chamber 70. Then, the glass beads 20 in the conduit 90 are sucked into the mixing chamber 70 via the negative pressure, and the water 18
To obtain the desired jet 22.

Therefore, if the pressure in the pipeline 90 is not maintained at a desired negative pressure state, the pipeline 90 is cracked, or the pipeline 90 is disengaged from the projection mechanism 24. You can see that something is wrong. For this reason,
If the operation of the strengthening device 10 is stopped at the time when the pressure detected by the negative pressure gauge 86 becomes abnormal, the abnormal state can be immediately eliminated, and the gear 1 can be efficiently and stably provided.
2. Strengthening treatment work of 2 becomes possible.

[0038]

As described above, in the gear strengthening device according to the present invention, the liquid is supplied from the first supply mechanism to the projection mechanism and the glass beads are supplied from the second supply mechanism to the projection mechanism. The jet of liquid and glass beads is projected onto the gear surface. 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, the second supply mechanism has a glass bead drying means to prevent the glass beads from adhering to each other due to moisture. Therefore, even if glass beads having a large amount of water absorption and a small particle size are used because the liquid is used, the glass beads are not clogged in the second supply mechanism, and the second supply mechanism causes a problem with respect to the projection mechanism. It becomes possible to reliably supply a fixed amount of the glass beads.

[Brief description of drawings]

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

FIG. 2 is a partial cross-sectional side view diagram of the strengthening device.

FIG. 3 is a perspective explanatory view of a laser flow meter that constitutes the above-mentioned strengthening device.

FIG. 4 is a view for explaining the operation of the strengthening device,
4A is an explanatory diagram of a tooth tip processing state, FIG. 4B is an explanatory diagram of a tooth surface processing state, and FIG. 4C is an explanatory diagram of a tooth root processing state.

FIG. 5 is an explanatory diagram when glass beads collide with a tooth surface.

6A and 6B are explanatory views before and after processing by the strengthening apparatus, FIG. 6A is an enlarged view of a portion corresponding to a reference pitch circle after carburizing and quenching processing, and FIG. 6B is a strengthening processing. It is an enlarged view of a portion corresponding to a reference pitch circle.

7A and 7B are explanatory views before and after the treatment by the strengthening device, FIG. 7A is an enlarged view of the tooth bottom after the carburizing and quenching treatment, and FIG. 7B is an enlargement of the tooth bottom after the strengthening treatment. It is a figure.

[Explanation of symbols]

10 ... Strengthening device 12 ... Gear 14 ... Casing 16 ... Gear holding mechanism 18 ... Water 20 ... Glass beads 22 ... Jet flow 24 ... Projection mechanism 26 ... Water supply mechanism 28 ... Glass bead supply mechanism 30 ... X-axis slide unit 32 ... Spindle unit 42 ... Spindle 46 ... Y-axis slide unit 48 ... Z-axis slide unit 66 ... Tube body 70 ... Mixing chamber 72 ... Nozzle 74 ... Water pipeline 80 ... Hopper 81 ... Heater 88 ... Laser flow meter 90 ... Pipeline 92 ... Mist Collection mechanism

Claims (4)

[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 toward the gear surface after heat treatment; A first supply mechanism for supplying the liquid, and a second supply mechanism for supplying the glass beads to the projection mechanism.
A gear strengthening device, comprising: a supply mechanism; and the second supply mechanism includes a glass bead drying unit for preventing the glass beads from adhering to each other due to water. 2. The strengthening apparatus according to claim 1, wherein the second supply mechanism has a tube body for allowing the glass beads to flow therethrough, and detects the amount of the glass beads flowing in the tube body. An apparatus for enhancing the strength of gears, comprising: 3. The strengthening device for a gear according to claim 2, further comprising a pressure sensor for detecting a pressure in the pipe body. 4. The apparatus for strengthening a gear according to claim 1, wherein the glass bead drying means includes a heater mounted on a hopper that stores the glass beads.