JP2779760B2 - Non-oxidizing induction hardening method and apparatus for worm - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a hardened layer in an atmosphere gas of a worm by induction hardening, particularly high-frequency bright quenching or non-oxidizing induction hardening, to a worm, and an apparatus for applying the method to the worm. Related to the device.

[0002]

2. Description of the Related Art Conventionally, a worm surface obtained by induction hardening.
The case hardening will be described with reference to FIG. War
Induction quenching of the worm W
A work rotating mechanism (not shown) that rotates as a center,
I-type root rotation rotation inserted between the teeth of the worm W
If the roasting high frequency heating coil 800 and this I-type root rotation
Rotating the worm W with the roasting high-frequency heating coil 800
A pair of guides 8 for moving according to the tooth space WB
10 and a jacket for injecting a cooling liquid to the worm W (see FIG.
(Not shown).

In other words, in such an induction hardening apparatus, the I-type root-rotating soaking high-frequency heating coil 800 is inserted into the inter-teeth WB of the worm W, and the I-type root-rotating soaking high-frequency heating coil 800 is inserted. The guide 810 is inserted into the inter-tooth WB adjacent to the inter-tooth WB. When the worm W is rotated, the I-type root rotation roasting high-frequency heating coil 800 is automatically moved between the teeth by the guide 810, so that the entire peripheral surface of the worm W can be heated.

[0004]

However, the above-described conventional induction hardening of the worm has the following problems. That is, since a black scale is formed on the surface of the hardened layer of the worm after quenching, a polishing operation or the like for removing the scale is required.

[0005] In addition, since the I-type root-rotating roasting high-frequency heating coil is inserted between the teeth of the worm, and the worm is rotated to heat each tooth in turn, the heating time tends to be long.

Further, as shown in FIG. 8, the hardened layer WA (shown by dots in the drawing) obtained by such a method is formed only on the tooth bottom WC and the tooth face WF, and has a tooth tip. It is not formed in the WT.

[0007] In addition, the worm is distorted when heated, but the distortion is not considered at all, and after the quenching is completed, it is corrected by a separate distortion correction device. Reality.

The present invention has been made in view of the above circumstances, and when induction hardening is performed on a worm, no scale is formed on the surface of the worm, and quenching of the worm is completed in a short period of time. Another object of the present invention is to provide a method and an apparatus for non-oxidative induction hardening of a worm, in which a hardened layer is formed and the strain can be further reduced.

[0009]

SUMMARY OF THE INVENTION
The non-oxidation induction hardening method is used for forming the worm gear.
Preliminary atmosphere filled with non-oxidizing or reducing gas
Loading the worm into the chamber and filling the worm with the gas.
After being carried into the oxidation chamber, the worm is raised by a line coil.
Frequency heating and immersing the heated worm in coolant
After immersing and cooling, transferring to outside the cooling liquid
And the above steps are continuously and automatically performed.
A non-oxidizing induction hardening method for the heating system,
In the process performed, the hardened layer formed on the worm
Stop heating before going deeper than depth
You.

The non-oxidizing induction hardening of the worm according to the present invention.
The equipment should be in a preliminary atmosphere filled with non-oxidizing or reducing gas.
The gas chamber is connected to the gas chamber and the preliminary atmosphere chamber, and is filled with the gas.
A non-oxidizing chamber where high-frequency heating of the worm is performed
The coolant tank containing the coolant in which the lower parts of both chambers are immersed
The worms from the atmosphere through the preliminary atmosphere chamber
Means to be transported to the oxidation chamber and worm to be transported to the non-oxidation chamber
A straightening roller to be placed on and a straightening roller placed on the straightening roller
Rotate the worm while supporting both ends of the worm
Work support rotating device and supported by this work supporting rotating device
A line coil for heating the heated worm,
On both sides supported by the work supporting and rotating device
Heating position with the straightening roller and the work support rotating device.
To the coolant, and after cooling,
And a cooling device, which is installed in the coolant and warms the coolant.
Jacket to cool the worm
Means for transferring the worm out of the coolant tank; and
Before the hardened layer formed in the system becomes deeper than the depth of the tooth valley
Control means for stopping heating.

[0011]

FIG. 1 is a schematic structural view of an embodiment of an apparatus capable of realizing the oxidization-free induction hardening method of a worm according to the present invention;
FIG. 2 is a side view of the straightening roller, FIG. 3 is a front view of the work supporting / rotating device and the straightening roller, FIG. 4 is a side view of the straightening roller and the work pushing device, FIG. Is a perspective view of a line coil used in the non-oxidizing induction hardening device of the worm, and FIG. 7 is a sectional view of the worm showing a hardened layer obtained by the non-oxidizing induction hardening device of the worm.

[0012] Warm-free oxidation induction hardening apparatus according to the present embodiment, the shutter S ₁ to one end, the preliminary atmosphere chamber 10 of lower open the shutter S ₂ is installed at the other end, through the shutter S ₂ A non-oxidizing chamber 20 which is connected to the preliminary atmosphere chamber 10 and is also open to the lower part;
And a coolant tank 10 provided below the non-oxidizing chamber 20
0.

In the cooling liquid tank 100, a cooling liquid L
₁ has been reservoir, the lower part of the preliminary atmosphere chamber 10 and the non-oxidizing chamber 20 is immersed in the cooling liquid L _1.

As means for carrying in the worm W, which is a work, the worm W is placed on the air and in the preliminary atmosphere chamber 1.
0, a walking beam 91 that moves between 0, and a worm W mounted thereon, and the preliminary atmosphere chamber 10 and the non-oxidizing chamber 20
And a walking beam 92 that moves between them.

Furthermore, the worm-free induction hardening apparatus for a worm according to the present embodiment uses the worm W carried into the non-oxidation chamber 20.
The correction roller 40 as a means for rotatably holding the worm W while correcting the distortion of the worm W, the work supporting rotation device 32 for rotating while supporting both end surfaces of the worm W, and the correction roller 40 are mounted on the correction roller 40. a line coil 30 to heat the warm W, straightening placed on the roller 40 raises the worm W supported by the workpiece supporting and rotating device 32 to the heating position, and after heating the work lifting apparatus is lowered into the cooling liquid L ₁ 50, the workpiece extrusion apparatus 56 for extruding over the cooling liquid L ₁ within the guide plate 58 cooled is complete warm-W from straightening rollers 41, 44 to move to the work increase device 60, the coolant warm W the workpiece increases device 60 for pushing up into the atmosphere from L within _1, a work unloading device 70 for unloading the worm W going out into the atmosphere and into the quenching apparatus outside the preliminary And 囲気 chamber 10 and a gas supply means 80 for supplying an atmospheric gas G to the non-oxidizing chamber 20.

The gas supply means 80 supplies a non-oxidizing atmosphere gas G such as nitrogen or argon or a reducing atmosphere gas G such as hydrogen. In the preliminary atmosphere chamber 10, a gas supply hole 83 for receiving the atmosphere gas G from the gas supply means 80 is provided at a lower portion, and a gas discharge hole 84 for discharging the atmosphere gas G is provided at a ceiling portion. The non-oxidizing chamber 20 is also provided with a gas supply hole 81 at a lower portion and a gas discharge hole 82 at a top portion.

As shown in FIG. 1, the non-oxidizing chamber 20 is formed in a substantially cylindrical shape. A line coil 30 is installed near the top of the non-oxidizing chamber 20 via a skirt 31 attached to the side wall 21.

As shown in FIG. 6, the line coil 30 has a first arc conductor 30A having a substantially quarter-arc shape and a first straight line connected to the end of the first arc conductor 30A so as to be orthogonal to the first arc conductor 30A. A semi-circular conductor 30C having a substantially semi-circular shape and connected to an end of the first linear conductor 30B;
A second linear conductor 30D connected to an end of the semi-circular conductor 30C and a substantially quarter-arc second circular conductor 30E connected to an end of the second linear conductor 30D Have.

The first arc-shaped conductor 30A and the second arc-shaped conductor 3
0E is provided so as to face the semicircular conductor 30C. On the other hand, the first linear conductor 30B and the second linear conductor 30D are installed so as to be parallel to the longitudinal axis of the worm W.

As shown in FIG. 2, the correction roller 40 includes a pair of rollers 41 and 41 mounted on a shaft 42 supported by a bearing 43, and a roller 44 mounted on a shaft 45 supported by a bearing 46. , A roller mounting base 47 to which the bearings 43 and 46 are fixed, and a roller rotation motor 48 (see FIG. 3) provided on the roller mounting base 47. In addition,
In this embodiment, a pair of correction rollers 40 are provided. However, more correction rollers can be provided according to the length of the worm W and the like.

As shown in FIG. 3, a worm end supporting device 33 for supporting one end of the worm W and a chuck 35 for gripping the other end of the worm W are disposed on the work supporting and rotating device 32 so as to face each other. I have. The worm end support device 33 and the chuck 35 have a worm end support device moving cylinder 34 for moving the worm end support 33 and the chuck 35 in the longitudinal direction of the worm W, respectively.
And a chuck moving cylinder 36. FIG. 37 shows a chuck rotating motor.

The worm end support device moving cylinder 34 and the chuck moving cylinder 36 are mounted on a roller mounting table 47 of the correction roller 40. The chuck rotation motor 37 and the roller rotation motor 48 are both waterproof and are supplied with power from a power supply box (not shown) provided in the non-oxidizing chamber 20 by a cabtire cord (not shown). Motor 37 and roller rotation motor 48
Even if immersed in ₁ , it can operate normally.

The work elevating device 50 includes a cooling liquid tank 10.
The cylinder 52 is provided with a cylinder 52 attached to the bottom 102 and a rod 51 which is advanced and retracted by the cylinder 52. A roller mount 47 for the correction roller 40 is fixed to the tip of the rod 51.

A work extruding device 56 as a means for pushing out the worm W from above the straightening roller 40 is mounted substantially horizontally on a column 53 erected at the bottom 102 of the cooling liquid tank 100 and on the top of the column 53. Cylinder 54
The worm W is advanced and retracted by the cylinder 54, and when advanced, the worm W placed on the correction rollers 41 and 44.
And a rod 55 for pushing out the worm W from above the straightening roller 40 onto the guide plate 58.

The work lifting device 60 is a work supporting member 6 for supporting the worm W, which has fallen from the straightening roller 40 via the guide plate 58, between the worm W and the wall of the coolant tank 100.
3, a rod 61 attached to a lower portion of the work supporting member 63, and a cylinder 62 for moving the rod 61 forward and backward.

The work carry-out device 70 is an inclined plate material arranged close to the coolant tank 100 so that the worm W placed thereon is rolled and carried out.

The coolant L ₁ stored in the coolant tank 100 is high-speed quenching oil or bright oil, etc. The coolant L ₁ contains a worm immersed in the coolant L _1. a pair of jackets 101, 101 are provided for rapidly cooling by spraying a cooling liquid L ₁ with respect to W.

The walking beams 91 and 92 are repeatedly moved in four directions in the directions of arrows A, B, C and D as shown in FIG. When the four-stage movement is completed, the worm W becomes the walking beams 91 and 92.
Is advanced by one groove of a fixed beam (not shown) arranged on the side of. Hereinafter, the movement of the worm W to the next groove is referred to as “the worm W has moved forward by one step”.

The first worm W is first placed in a groove corresponding to the right end (right end in the drawing) groove 93 of the walking beam 91 at the first groove of the fixed beam (not shown). As the walking beams 91 and 92 repeatedly move in the four stages, the worm W moves forward by one step.

When the worm W moves forward by the first step, the second worm W ₂ (the second worm W ₂
Is assigned. Hereinafter, the third, fourth,... Worms are similarly denoted by W ₃ , W ₄ ,. ) Is placed in the groove on which the worm W is placed at the beginning of the fixed beam. Hereinafter, the worms W ₃ , W ₄ ,...

By the operation of the walking beams 91 and 92, the worm W is carried into the non-oxidizing chamber 20 through the preliminary atmosphere chamber 10. However, walking beam 91 and the 92, while with the movement of the process of the arrows B, C and D are open the shutter S ₁ and the shutter S _2, are closed at other times.

The non-oxidizing chamber 20 is formed by the walking beam 92.
At this time, the worm W transported to the worm end supporting device moving cylinder 34 of the worm end supporting device of the work supporting rotating device 32 and By the operation of the chuck moving cylinder 36, both ends of the worm W are supported between the worm end support device 33 and the chuck 35.

Next, the cylinder 5 of the work lifting device 50
2 to raise the roller mounting base 47, and
W is placed between the line coil 30 which is a high-frequency heating coil.
After that, the chuck rotation motor 37 and the roller rotation
Start operation with the motor 48 to rotate the worm W
You. Then, the high-frequency current from the high-frequency power supply 200 is
Heating the worm W for a predetermined time by energizing the coil 30
You. The heating time of the worm W is controlled by a control means (not shown).
Worm, as shown in FIG.
The hardened layer WA formed on the W is the depth of the tooth valley,
In the time that does not become deeper than the depth from the front WT to the interdental WC
Is set. Thereby, the outer shape of the worm W tooth
Is formed along the hardened layer WA. This line coil 3
The heating of the worm W by 0
Over the conventional I-type root rotation
Completes heating in a very short time with the high-frequency heating coil 800
Can be completed.

When the heating is completed, the cylinder 52 is operated to move the rod 51 backward, and the rotating worm W is moved together with the straightening roller 40 and the work supporting / rotating device 32 into the cooling liquid L ₁ of the cooling liquid tank 100. submerged within, while continuing to rotate the worm W, rapidly cools the warm W from a pair of jacket 101, 101 provided in the coolant tank 100 by spraying a cooling liquid L ₁ to the worm W.

When the cooling of the worm W is completed, the chuck rotation motor 37 and the roller rotation motor 48 are stopped, and the cylinder 55 of the work extruder 56 is operated so that the rod 55 is advanced.
1, 44, and is transferred over the guide plate 58 to reach the work supporting member 63, where the cooling liquid tank 10
Stops on the 0 side wall.

Next, when the rod 61 is raised by operating the cylinder 62, the worm W
It rises along the side walls of the moment beyond the side walls of the exit liquid level of the cooling liquid L ₁ coolant tank 100, the work unloading device 7
The workpiece is rolled over the workpiece 0 and transported to a predetermined place by the work unloading device 70.

As described above, according to this embodiment, the worm W is very effectively non-oxidized and induction-fired. The worms W ₂ , W ₃ ,... Following the worm W are similarly hardened.

If the worm W is quenched by the non-oxidizing induction hardening device of the worm described above, not only the inter-tooth WC and the tooth face WF but also the tooth tip W as shown in FIG.
A cured layer WA is also formed on T.

Non-oxidative induction hardening of the worm according to the present invention
The method comprises the steps of making the worm constituting the worm gear non-oxidizing or non-oxidizing.
Is a process of transporting to a preliminary atmosphere chamber filled with reducing gas
And carried the worm into the non-oxidizing chamber filled with the gas.
A step of high-frequency heating the worm with a line coil later
After immersing the heated worm in cooling liquid and cooling
Having a step of transferring out of the cooling liquid, and
Each process is continuously performed automatically.
In the quenching method, the step of performing the high-frequency heating includes:
The hardened layer formed in the worm is deeper than the depth of the tooth valley
The heating is stopped before. For this reason,
The surface of the worm when induction hardening
The quenching can be performed without forming a metal. Ma
In addition, the hardened layer that is formed is shaped according to the outer shape of the worm teeth.
The hardened layer is formed on the tooth tip
Thus, a better worm can be obtained.

Further, the worm according to the present invention has a non-oxidizing high-period.
The wave quenching equipment should be filled with non-oxidizing or reducing gas.
A gas atmosphere chamber is connected to the preliminary atmosphere chamber,
-Free chamber where high frequency heating of worm is performed by filling
And a cooling fluid in which a lower part of both chambers is immersed.
The waste liquid tank and the worm are moved from the atmosphere through the preliminary atmosphere chamber.
Means to carry into the oxidation-free chamber by
Roller on which the form is to be placed, and
Rotate the worm while supporting both ends of the worm
Work supporting and rotating device and work supporting and rotating device
A line coil for heating the worm supported by
It is placed on the positive roller and both ends are supported by the work support rotating device.
Worm with straightening roller and workpiece support rotating device
Raise to the heating position and drop into the coolant after cooling
A work elevating device that is installed in the coolant and cools the coolant.
A jacket that cools the worm by spraying
Means for transferring the rejected worm out of the coolant tank;
The hardened layer formed on the worm is deeper than the depth of the tooth valley.
Control means for stopping the heating before the heating. others
Quenching without forming scale on the worm surface
And quenching of the worm in a short time
Is completed, a hardened layer is formed on the tooth tips, and strain is reduced.
Can be reduced. That is, with a line coil
For heating, conventional I-type root rotation roasting high-frequency heating
Need to move the coil along the teeth like a thermal coil
Heating is completed in a short time because there is no
Between. In addition, the hardened layer formed on the worm is
Control means to stop heating before it becomes deeper than
The hardened layer is deeper than the depth of the tooth valley
Heating time can be shortened. For this reason, heating
Since the time required is short, the time required for quenching
It will be shorter.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of an apparatus capable of realizing a worm-free induction hardening method of a worm according to the present invention.

FIG. 2 is a side view of a straightening roller.

FIG. 3 is a front view of a work supporting rotation device and a correction roller.

FIG. 4 is a side view of a straightening roller and a work pushing device.

FIG. 5 is an explanatory diagram of an operation of a walking beam.

FIG. 6 is a perspective view of a line coil used in the non-oxidizing induction hardening device of the worm.

FIG. 7 is a sectional view of the worm showing a hardened layer obtained by the non-oxidizing induction hardening device of the worm.

FIG. 8 is a sectional view of a worm showing a conventional induction hardening method for the worm and its problems.

[Explanation of symbols]

 Reference Signs List 10 Preliminary atmosphere chamber 20 Non-oxidizing chamber 30 Line coil 40 Straightening roller 50 Work lifting device 60 Work lifting device 70 Work unloading device W worm

Claims (2)

(57) [Claims] A worm constituting a worm gear is made of a non-acid
Carry in a preliminary atmosphere chamber filled with oxidizing or reducing gas
Transporting the worm to an oxidation-free chamber filled with the gas.
After the worm is inserted, the worm is heated with a line coil.
And immersing the heated worm in a coolant to cool
After the cooling liquid is transferred to the outside of the cooling liquid,
Each of the above processes is continuously and automatically performed without oxidizing the worm
In the induction hardening method, in the step of performing the induction heating,
Indicates that the hardened layer formed on the worm is deeper than the depth of the tooth valley.
A non-oxidizing induction hardening method for worms , wherein heating is stopped before the worm becomes cold . 2. A method in which a non-oxidizing or reducing gas is filled.
A gas atmosphere chamber is connected to the preliminary atmosphere chamber,
-Free chamber where high frequency heating of worm is performed by filling
And a cooling fluid in which a lower part of both chambers is immersed.
The waste liquid tank and the worm are moved from the atmosphere through the preliminary atmosphere chamber.
Means to carry into the oxidation-free chamber by
Roller on which the form is to be placed, and
Rotate the worm while supporting both ends of the worm
Work supporting and rotating device and work supporting and rotating device
A line coil for heating the worm supported by
It is placed on the positive roller and both ends are supported by the work support rotating device.
Worm with straightening roller and workpiece support rotating device
Raise to the heating position and drop into the coolant after cooling
A work elevating device that is installed in the coolant and cools the coolant.
A jacket that cools the worm by spraying
Means for transferring the rejected worm out of the coolant tank;
The hardened layer formed on the worm is deeper than the depth of the tooth valley.
Control means for stopping heating before heating
Warm-free oxidation induction hardening apparatus according to.