JPH10204524A - Induction hardening apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an induction hardening apparatus which can increase the production quantity even in the case a columnar metallic parts is long or short. SOLUTION: On pair of rolling rolls 40 for supporting the carried metallic parts 12a, 12b, 12c are arranged between an induction heating coil 22 and a cooling jacket 24. The one pair of rolling rolls 40 are composed of a supporting roller 42 fixed to a rotary shaft 20a of a rotary drum 16 and a rotary drum 18, and a supporting roller fixed to a rotary shaft of a rotary drum and a rotary drum, and rotated together with the first and the second rotary drums 16, 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an induction hardening apparatus for carrying out induction hardening while conveying a cylindrical metal member in its longitudinal direction and rotating it in the circumferential direction.

[0002]

2. Description of the Related Art Conventionally, induction hardening for hardening a surface layer of a metal member using induction heating has been widely performed. There are various types of induction hardening devices for performing such induction hardening, and one of them is to convey a cylindrical metal member in its longitudinal direction and quench while rotating it in its circumferential direction. Induction hardening devices are known.

This induction hardening apparatus includes, for example, an induction heating coil for induction heating a metal member, and a cooling jacket for rapidly cooling the metal member heated by the induction heating coil. Are arranged side by side in the transport direction of the columnar metal member. Further, two transfer devices for transferring the cylindrical metal member are disposed at positions on both sides of the induction heating coil and the cooling jacket, respectively.

When a cylindrical metal member is induction hardened using the induction hardening apparatus, generally, a large number of cylindrical metal members are successively conveyed in a longitudinal direction while the metal members are sequentially heated by induction heating. Heat with a coil and quench with a cooling jacket. Therefore, in order to increase the production amount with this induction hardening apparatus, the conveying speed for conveying the cylindrical metal member is increased, or the power supply capacity is increased.

[0005]

In order to increase the conveying speed of the cylindrical metal member, the heating zone of the induction heating coil is lengthened so that the cylindrical metal member is uniformly heated to the quenching temperature. You need to do that. Further, the cooling zone of the cooling jacket needs to be long so that the columnar metal member is sufficiently cooled rapidly. For this reason, the length of the induction heating coil and the cooling jacket becomes longer in the transport direction, and as a result, the distance between the two transporting devices disposed on both sides of the induction heating coil and the cooling jacket becomes longer.

[0006] Between these two transfer devices, the cylindrical metal member is transferred without contacting the induction heating coil and the cooling jacket. For this reason, when the distance between these two transfer devices is increased, the cylindrical metal member having a short length falls between the two transfer devices during transfer. Therefore, the length of the cylindrical metal member that can be conveyed is limited to some extent.
On the other hand, in order to be able to convey a cylindrical metal member having a short length, it is necessary to shorten the interval between the two conveying devices. In this case, the soaking zone of the induction heating coil and the cooling zone of the cooling jacket cannot be lengthened. Therefore, the conveying speed of the cylindrical metal member cannot be increased, and the production amount cannot be increased.

[0007] It is an object of the present invention to provide an induction hardening apparatus capable of increasing the production amount even if the length of a cylindrical metal member is long or short.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, an induction hardening apparatus according to the present invention conveys a cylindrical metal member in a longitudinal direction and performs an induction hardening while rotating in a circumferential direction. (1) transport means for transporting the cylindrical metal member in the longitudinal direction while rotating the cylindrical metal member in the circumferential direction; (2) holding means for pressing the cylindrical metal member being transported by the transport means (3) An induction heating coil disposed on the downstream side in the transportation direction from the transportation unit for induction heating the cylindrical metal member transported by the transportation unit; and (4) disposed on the downstream side in the transportation direction from the induction heating coil. In addition, a cooler for cooling the cylindrical metal member induction-heated by the induction heating coil. (5) A columnar metal disposed downstream of the cooler in the transport direction. Rotating means for rotating the member in the circumferential direction thereof; (6) supporting means for supporting the cylindrical metal member passing between the conveying means and the rotating means, which is disposed between the conveying means and the rotating means, is provided. It is characterized by the following.

Here, the transporting means comprises: (7) a pair of first extending parallel to the transporting direction, rotating the columnar metal member in the circumferential direction by rotating in the same direction close to each other; Rotary Drum (8) It is preferable that the rotary drum is provided with a caterpillar for transporting the columnar metal members mounted on the pair of first rotary drums in the transport direction.

It is preferable that the pressing means includes: (9) a pressing roller which comes into contact with the cylindrical metal member and rotates as the cylindrical metal member rotates in the circumferential direction.

Further, it is preferable that the pressing roller has a structure in which (10) the rotation axis of the pressing roller is inclined at an angle within a range of 60 ° or more and 85 ° or less with respect to the transport direction.

Further, it is preferable that the rotating means includes: (11) a pair of second rotating drums coaxial with each of the pair of first rotating drums.

Further, it is preferable that the support means is (12) arranged between the induction heating coil and the cooler.

Further, the supporting means comprises: (13) a pair of supporting members fixed to the rotating shafts of the first rotating drum and the second rotating drum and rotating together with the first and second rotating drums, It is preferable that it is made of a roller.

Further, it is preferable that each of the pair of support rollers is composed of (14) a plurality of divided rollers.

Here, the columnar metal member refers to a cylindrical metal member including a hollow member and a solid member.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an induction hardening apparatus according to the present invention will be described with reference to the drawings.

A first embodiment of the induction hardening apparatus of the present invention will be described with reference to FIGS.

FIG. 1 is a side view schematically showing a first embodiment of the induction hardening apparatus of the present invention. FIG. 2 is a sectional view taken along line AA of the induction hardening apparatus of FIG. 1, and FIG. 3 is a sectional view taken along line BB of the induction hardening apparatus of FIG. FIG. 4 is a side view schematically showing the presser.

In the induction hardening apparatus 10 shown in FIG. 1, a large number of hollow or solid cylindrical metal parts (one example of a cylindrical metal member according to the present invention) 12a, 12b and 12c are connected to their long sides. Direction (the direction of arrow C and the transport direction)
These metal parts 12a, 12c are continuously transported while rotating in the circumferential direction (the direction of arrow D).
12b and 12c are sequentially quenched. A caterpillar 14 that rotates in the directions of arrows E and F and conveys the metal parts 12a, 12b, and 12c in the direction of arrow C is disposed upstream in the transport direction. In FIG. 1, the caterpillar 14 is arranged at a position close to the induction heating coil 22, but in practice, the caterpillar 14 is arranged further upstream in the transport direction.

A pair of first rotating drums 16 for rotating the metal parts 12a, 12b, 12c in the circumferential direction are arranged slightly downstream of the caterpillar 14 in the transport direction. As shown in FIG. 2, the pair of first rotating drums 16 are composed of two rotating drums 16a and 16b which are close to each other and extend in parallel in the transport direction, and the two rotating drums 16a and 16b are indicated by arrows G and H, respectively. Direction (same direction)
To rotate.

A pair of second rotating drums 18 is located at a position away from the first rotating drum 16 by a distance L on the downstream side in the transport direction.
Is arranged. Like the first rotating drum 16, the second rotating drum 18 also includes two rotating drums 18a and 18b (the rotating drum 18b is not shown) which are adjacent to each other and extend in parallel in the transport direction. Rotating drum 16
a and the rotating drum 18a are connected by one rotating shaft 20a, and when the rotating drum 16a rotates in the direction of arrow G, the rotating drum 18a also rotates in the direction of arrow G. Similarly, the rotating drum 16b and the rotating drum 18b
Are also connected by one rotating shaft 20b.
When the drum 6b rotates in the direction of arrow H, the rotary drum 18b also rotates in the direction of arrow H.

First rotary drum 16 and second rotary drum 18
Between them, as shown in FIG. 1, a four-turn induction heating coil 22 and a cooling jacket through which metal parts 12a, 12b, and 12c pass through a hollow portion 24a (an example of a cooler according to the present invention) 24 are arranged. The induction heating coil 22 is disposed downstream of the first rotary drum 16 in the transport direction, and the metal components 12 a and 12 transported while being rotated by the caterpillar 14 and the first rotary drum 16.
The surface layers b and 12c are induction-heated. On the other hand, the cooling jacket 24 is disposed downstream of the induction heating coil 22 in the transport direction, and is for rapidly cooling the metal components 12a, 12b, and 12c that have been induction-heated by the induction heating coil 22.

Above a portion of the first rotary drum 16 close to the induction heating coil 22, a presser 26 for pressing the conveyed metal parts 12a, 12b, 12c from above is arranged. The presser 26 includes metal parts 12a and 12a.
b, 12c and a pressing roller 28 that presses these members in contact with the metal parts 12a, 1c.
It rotates with the circumferential rotation of 2b and 12c. The holding roller 28 is rotatably fixed to the support member 30. The support member 30 is connected to a cylinder 34 via a rod 32, and the pressing roller 28 presses the metal component 12 with a pressing force of, for example, 0.1 to 0.5 kg / cm ^2.
a, 12b, and 12c. The presser 26 is also disposed above a portion of the second rotary drum 18 near the cooling jacket 24, and the two pressers 26 press the metal components 12a, 12b, and 12c. For this reason, the metal parts 12a, 1
2b and 12c are transported while rotating reliably. Also,
Even if a metal component shorter than the distance between the first rotary drum 16 and the second rotary drum 18 is conveyed and the center of gravity of the metal component comes off the first rotary drum 16, the metal component is pressed by the presser 26. As long as the metal parts do not fall.

Here, referring to FIG.
The relationship between the rotation axis and the transport direction will be described.

FIG. 5 is a plan view schematically showing the angle between the rotation axis of the pressing roller 28 and the conveying direction.

The pressing roller 28 is arranged so that the rotating shaft 28a of the pressing roller 28 is inclined by an angle α in the range of 60 ° or more and 85 ° or less with respect to the transport direction (the direction of arrow C). As a result, the metal component 12b is braked, so that the metal component 12b heated by the induction heating coil 22 is prevented from being sent too fast, and the plurality of metal components 12a, 12b, 12
There is no gap between c.

Referring again to FIGS. 1 and 3, the induction hardening apparatus 10 will be described.

Induction heating coil 22 and cooling jacket 24
And between the metal parts 12a, 12b,
A pair of support rollers 40 supporting 12c is arranged. The pair of support rollers 40 include a support roller 42 fixed to the rotating shaft 20a of the rotating drum 16a and the rotating drum 18a, and a supporting roller 44 fixed to the rotating shaft 20b of the rotating drum 16b and the rotating drum 18b. The support rollers 42 and 44 rotate with the first and second rotating drums 16 and 18 in close proximity to each other.

Since the pair of support rollers 40 are arranged between the induction heating coil 22 and the cooling jacket 24 as described above, even if the metal part 12b is about half the distance L, for example, 12b is the first rotating drum 1
6 and the second rotating drum 18 are conveyed without falling. Therefore, even if the distance L is increased by lengthening the soaking zone of the induction heating coil 22 and the cooling zone of the cooling jacket 24 in order to increase the production rate by increasing the conveying speed of the metal parts, the distance L becomes longer. It can harden metal parts of about half the length. As a result, in the induction hardening apparatus 10, the production amount can be increased regardless of whether the length of the metal parts 12a, 12b, 12c is long or short, and a versatile hardening apparatus can be obtained. Note that the presser 26 is disposed above the support roller 40 so that the metal parts 12a, 12b, 1
2c may be held down.

Referring to FIGS. 6 and 7, support rollers 42,
The structure of 44 will be described.

FIG. 6A is a perspective view schematically showing a support roller divided into two parts, and FIG. 6B is a perspective view schematically showing a support roller fixed to a rotating shaft. FIG.
(A) is a front view of a support roller, (b) is a side view of a support roller. In these drawings, the same components as those in FIGS. 1 to 5 are denoted by the same reference numerals. Since the two support rollers 42 and 44 have the same structure, the support roller 42 will be described here.

The support roller 42 is composed of two half-split rollers (one example of a plurality of split rollers according to the present invention) 42a, 42a.
and two bolt holes 43a and 43b are formed in each of the half rollers 42a and 42b.
In order to unite the half rollers 42a and 42b and fix them to the rotating shaft 20a, the half rollers 42a and 42b
a, and bolts are inserted into the bolt holes 43a and 43b and tightened. Thereby, the support roller 42 is fixed to the rotating shaft 20a. Since the support roller 42 is thus composed of the two half rollers 42a and 42b, the support roller 42 can be easily fixed to an arbitrary position on the rotating shaft 20a. Here, two half rollers are shown as an example of the plurality of divided rollers, but three or more divided rollers may be used.

Referring to FIG. 8, a second embodiment of the induction hardening apparatus according to the present invention will be described.

FIG. 8 is a side view schematically showing a second embodiment of the induction hardening apparatus according to the present invention, wherein the same components as those in FIG. 1 are denoted by the same reference numerals.

The induction hardening device 50 is characterized by three support rollers 52 for supporting the conveyed cylindrical metal parts,
54 and 56 are the first rotating drum 16 and the second rotating drum 18
Is located between In addition, three support rollers 5
In order to arrange 2, 54, 56, three cooling jackets 58, 60, 62 separated from each other were arranged. The supporting roller 52 is disposed between the induction heating coil 22 and the cooling jacket 58, the supporting roller 54 is disposed between the cooling jacket 58 and the cooling jacket 60, and the supporting roller 56 is connected between the cooling jacket 60 and the cooling jacket 62. Placed between.

As described above, the three support rollers 52, 54, 56 are provided between the first rotary drum 16 and the second rotary drum 18.
Are arranged, for example, when the columnar metal part has a distance L ′ of 4
Even with a length of about one-half, the metal component is conveyed without falling between the first rotating drum 16 and the second rotating drum 18. Therefore, in order to increase the production rate by increasing the conveying speed of the metal parts, even if the uniforming zone of the induction heating coil 22 and the cooling zone of the cooling jackets 58, 60, and 62 are lengthened, the distance L 'becomes longer. A metal part having a length of about の of the distance L ′ can be hardened. As a result, in the induction hardening device 50, even if the length of the metal component is short, the production amount can be further increased, and a more versatile hardening device can be obtained. The support rollers 52, 54, 56
The presser 26 may be arranged above the metal part to hold the metal part being conveyed.

Next, the results of an experiment in which a metal part is induction hardened using the induction hardening apparatus 10 shown in FIG. 1 will be described.

In this experiment, hollow cylindrical metal parts of two sizes were used. One has an outer diameter of 31.8 mm, a thickness of 2.0 mm, and a length of 1500 mm (A type), and the other has an outer diameter of 35 mm, a thickness of 3.5 mm, and a length of 630 mm ( B type). The distance L between the first rotary drum 16 and the second rotary drum 18 shown in FIG. 1 was 420 mm, and the transport speed of the metal parts was 146 mm / sec for the A type and 77 mm / sec for the B type.
The induction heating device connected to the induction heating coil 22 was set to a frequency of 8.2 kHz and an output of 200 kW, and a cooling liquid of 160 liters / min was jetted from the cooling jacket 24 to remove the above-described cylindrical metal parts of each type. Induction hardened. After this quenching, the run-out, extension, and outer diameter of each type of cylindrical metal component were measured.

The method of measuring the shake will be described with reference to FIG.

FIG. 9 is a schematic diagram showing a method of measuring the shake.

A fixed roller 72 and a follow-up roller 74 are arranged at positions corresponding to both ends of a test piece (cylindrical metal part) 70, and both ends of the test piece 70 are mounted on these rollers 72, 74. And rotate it. In addition, test piece 7
A distortion detection roller 76 is disposed above the center of the zero. In FIG. 9, the strain detection roller 76 is illustrated as being arranged on the side of the test piece 70, but the strain detection roller 76 is actually arranged above the test piece 70. The distortion detecting roller 76 is rotatably fixed to the support member 78. When the test piece 70 is shaken, for example, as indicated by a dashed line 70 ', the amount of this shake is determined by the support member 78 and the GA.
The distance G from the P sensor 80 is represented. The electric signal representing the interval G is obtained by the GAP sensor 80. This electric signal is amplified by the amplifier 82 and sent to the sequencer 84, where it is converted into a digital value. Sequencer 84
, The maximum value of the measured intervals G is always stored. Here, the value obtained by dividing the maximum value by 2 is referred to as test piece 7
0 “run-out”.

In measuring the "run-out" of the test piece 70, the rotation speed of one of the two follow-up rollers 74 is measured by the rotation detector 86.
The interval G was measured at intervals of 0 ms (20 × 10 ⁻³ seconds).
The elongation and the outer diameter of the test piece 70 were measured by a known method using a micrometer or the like.

The results are shown in Table 1.

[0045]

[Table 1] The results shown in Table 1 show that A type has 29 pieces and B type has 30 pieces.
It is the result of having measured about the cylindrical metal part of a book. Table 1
As shown in the figure, the run-out standard is 2.4 mm for the A type.
On the other hand, the run-out of the 29 test pieces 70 is 0.50
It was in the range of １1.41 mm, and there was little bending. In the B type, the run-out standard is 0.88 mm, while the run-out of 30 test pieces 70 is 0.2 to 0.67 mm.
mm and a small bend. Also, as shown in Table 1, the average value x and the standard deviation value σ of the shake are
The results were good for both type and type B.

The elongation of the test piece is 1507.
Within the range of 8 to 1508.4 mm, and 6 for the B type.
The range was 33.7 to 634.5 mm, and the elongation was small. Table 1 also shows the average value x and the standard deviation value σ of elongation.
As shown in the figure, both the A type and the B type showed good results.

In measuring the outer diameter of the test piece, the outer diameter was measured at each of the front end, the center, and the rear end of the test piece. The standard of the outer diameter was within the range of ± 0.25 mm, and all the measurement results were within this range.

As described above, when the metal parts are induction hardened using the induction hardening apparatus 10, not only the production amount can be increased, but also the deformation of the induction hardened metal parts is reduced.

[0049]

As described above, according to the induction hardening apparatus of the present invention, the cylindrical metal part passing between the conveying means and the rotating means is supported by the supporting means, so that the conveying means and the rotating means are supported. It is possible to harden even a cylindrical metal part shorter than the interval with the rotating means. For this reason, even if the length of the cylindrical metal component is long or short, it can be conveyed at a high speed to increase the production amount, and a versatile quenching device can be obtained. Moreover, since the cylindrical metal component being conveyed by the conveying means is pressed by the pressing means, the cylindrical metal component can be reliably rotated, and distortion such as run-out and elongation can be reduced.

Here, a pair of first rotating drums extending in parallel with the transport direction, wherein the transport means rotate in the circumferential direction by rotating the columnar metal part in the same direction by rotating in the same direction close to each other, In the case where a caterpillar that conveys the cylindrical metal component placed on the first rotating drum in the conveying direction is provided, the cylindrical metal component can be conveyed while rotating with a relatively simple configuration.

In the case where the holding means is provided with a holding roller which comes into contact with the cylindrical metal part and rotates as the cylindrical metal part rotates in the circumferential direction, the cylindrical metal part is damaged. It can be rotated without any trouble.

Further, in the case where the press roller has a rotation axis of the press roller inclined at an angle within a range of 60 ° or more and 85 ° or less with respect to the conveyance direction, the pressurized roller may have a cylindrical metal part being conveyed. Since the brake is applied, the cylindrical metal component is prevented from being sent too fast, and the cylindrical metal component can be transported at an appropriate transport speed.

Further, when the rotating means has a pair of first rotary drums and a pair of second rotary drums coaxial with each other, the cylindrical metal component can be rotated with a relatively simple configuration. it can.

Further, when the supporting means is disposed between the induction heating coil and the cooling jacket, a shorter cylindrical metal part can be transported by a small number of supporting means.

Further, the support means is fixed to the rotating shafts of the first rotating drum and the second rotating drum, and the first and second rotating drums are fixed.
In the case of a pair of supporting rollers which rotate together with the rotating drum and are close to each other, the cylindrical metal parts are not damaged and the rotation is not hindered.

Further, when each of the pair of support rollers is composed of a plurality of split rollers, the pair of support rollers can be easily fixed at any position on the rotating shaft.

[Brief description of the drawings]

FIG. 1 is a side view schematically showing a first embodiment of an induction hardening apparatus of the present invention.

FIG. 2 is a sectional view taken along line AA of the induction hardening apparatus of FIG.

FIG. 3 is a sectional view of the induction hardening apparatus of FIG. 1 taken along line BB.

FIG. 4 is a side view schematically showing a presser of the induction hardening apparatus of FIG. 1;

FIG. 5 is a plan view schematically showing an angle between a rotation axis of a pressing roller and a conveyance direction.

FIG. 6A is a perspective view schematically showing a support roller divided into two parts, and FIG. 6B is a perspective view schematically showing a support roller fixed to a rotating shaft.

FIG. 7A is a front view of a support roller, and FIG. 7B is a side view of the support roller.

FIG. 8 is a side view schematically showing a second embodiment of the induction hardening apparatus of the present invention.

FIG. 9 is a schematic view showing a method of measuring shake.

[Explanation of symbols]

 10, 50 Induction hardening device 12a, 12b, 12c Columnar metal part 14 Caterpillar 16 First rotating drum 18 Second rotating drum 20a, 20b Rotating shaft 22 Induction heating coil 24, 58, 60, 62 Cooling jacket 26 Presser 28 Holding roller 40 A pair of support rollers 42, 44 Support rollers 42a, 42b Half roller L, L 'Distance between the first rotating drum and the second rotating drum

Claims (8)

[Claims] An induction hardening device for conveying a cylindrical metal member in a longitudinal direction thereof and performing induction hardening while rotating the cylindrical metal member in a circumferential direction thereof, wherein the cylindrical metal member is rotated in the circumferential direction while rotating the cylindrical metal member in the circumferential direction. Transporting means for transporting the cylindrical metal member transported by the transporting means, and a pressing means for pressing the cylindrical metal member transported by the transporting means; and a columnar metal transported by the transporting means disposed downstream of the transporting means in the transporting direction. An induction heating coil for induction heating the member, a cooler disposed downstream of the induction heating coil in the transport direction and cooling a columnar metal member induction-heated by the induction heating coil; and Rotating means for rotating the cylindrical metal member in the circumferential direction thereof, which is arranged on the downstream side in the conveying direction, and which is arranged between the conveying means and the rotating means, And a supporting means for supporting the cylindrical metal member passing through the space. 2. A pair of first rotating drums extending in parallel with the transport direction, wherein the transport means rotates in a circumferential direction by rotating the columnar metal member in a circumferential direction by rotating in the same direction close to each other; 2. The induction hardening device according to claim 1, further comprising a caterpillar for transporting the cylindrical metal member mounted on the pair of first rotary drums in the transport direction. 3. The pressing means comprises a pressing roller which comes into contact with the cylindrical metal member and rotates as the cylindrical metal member rotates in the circumferential direction. Or the induction hardening apparatus according to 2. 4. The pressing roller according to claim 3, wherein a rotation axis of the pressing roller is inclined at an angle of 60 ° or more and 85 ° or less with respect to the transport direction. Induction hardening equipment. 5. The rotating means comprises a pair of second rotary drums coaxial with each of the pair of first rotary drums.
3. The induction hardening device according to claim 2, further comprising a rotary drum. 6. The high-frequency device according to claim 1, wherein the supporting unit is disposed between the induction heating coil and the cooler. Quenching device. 7. The supporting means is fixed to a rotating shaft of the first rotating drum and the second rotating drum, and rotates together with the first and second rotating drums.
7. The induction hardening device according to claim 5, wherein the induction hardening device comprises a pair of support rollers close to each other. 8. The induction hardening device according to claim 7, wherein each of said pair of support rollers is composed of a plurality of divided rollers.