JP2001020012A - Heat treatment apparatus for long work and method for controlling heat treatment for long work used in this apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a long work heating treatment device, etc., with which the heat treatment can be applied to the long work into a hardening depth within the specification range while executing the control of extension. SOLUTION: This heat treatment apparatus is provided with a high frequency induction heating coil body 911, an electric source part D for supplying the electric power to this coil body, a shifting mechanism 930 for shifting the coil body 911 along the work W, a length measuring instrument 953 for measuring the whole length of the work W during heating and a control unit (not show in the figure) for controlling the supplied electric power to control the heating quantity to the incompleting part of heating in the work W by using the extending data measured with the length measuring instrument 953. The control unit has a storing part for storing the reference data of the extension measured at the time when a work for obtaining pre-data as the same as the actual work W is hardened into a prescribed hardened depth, the electric power at this time, the shifting speed of the coil body 911 at this time and the electric power, with which the hardened depth in this shifting speed becomes the allowable max. value and the allowable min. value, and a comparing control part for comparing the extension data of the actual work W measured during heating-stopping and shifting-heating with the reference data and changing the electric power so as to equalize with the reference data, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat treatment apparatus for a long work such as a ball screw, and a heat treatment control method for a long work used in the apparatus. The heat treatment here is induction hardening or induction hardening + induction hardening.

[0002]

2. Description of the Related Art A long body such as a ball screw is subjected to a heat treatment such as quenching or quenching + tempering at a manufacturing stage. For example, when a screw needs to be formed at a precise pitch, such as a ball screw, it is necessary to perform heat treatment such as quenching in consideration of elongation during heat treatment such as quenching.

A schematic drawing of a conventional induction hardening device for a ball screw as a long heat treatment device for a long workpiece shows a heat treatment device (an induction hardening device for a ball screw) according to an embodiment of the present invention described later. Therefore, a conventional induction hardening device for a ball screw will be described with reference to FIG.

A conventional induction hardening device using a ball screw as a workpiece W is a so-called moving quenching device, and includes a quenching mechanism 910, a moving mechanism 930 for moving the quenching mechanism 910 along the workpiece W, A rotation / elongation detection mechanism 950 that rotates the work W and detects elongation of the work W
And a control unit (not shown) for controlling these.

The quenching mechanism 910 includes a so-called saddle-type high-frequency heating coil 911 and the high-frequency heating coil 911.
And a cooling jacket 914 that injects a cooling liquid for quenching. The power supply unit D
It comprises a current transformer 912 and a high-frequency oscillator 913. The quenching mechanism 910 is movably attached to a later-described ball screw 931 of the moving mechanism 930.

The moving mechanism 930 includes a ball screw 931 installed in parallel with the workpiece W and a motor 9 for rotating the ball screw 931.
32.

The rotation / elongation detecting mechanism 950 includes a chuck 951 for holding one end of the work W for rotating the work W, and a motor 95 for rotating the chuck 951.
2, a pair of the chuck 951 and a length measuring device 95 for pressing the center of the other end of the work W and detecting the extension of the work W
And 3.

In the conventional induction hardening apparatus configured as described above, the workpiece W is hardened as follows.

First, as a preliminary preparation, one work similar to the production work W to be hardened is prepared, and the work is hardened under standard conditions satisfying the target best value (standard value) of the hardening specification. To obtain reference data described later. For example, the quenching depth of the quenching specification (standard range of quenching depth) is 4.
If it is 5 ± 0.5 mm, the target best value is 4.5 mm
become. The standard conditions here are, for example, that the power given to the high-frequency heating coil body 911 is 100 kW, the quenching mechanism 910 is used.
Is 10 mm / sec (constant). These conditions are set in the control unit, and the work is hardened. Before the quenching (moving quenching), stop heating is often performed, regardless of whether the work acquires the reference data or a production work W to be described later.

After the work is quenched, the length measuring device 953 measures how long the entire length of the work has been extended after the work is completely cooled. The elongation is calculated from the measured value. For example, if the entire length of the work is 1 m and the work is elongated by 1 mm after quenching, the elongation rate of the work is 1 per mill. This elongation rate becomes a reference elongation rate (reference data) and is set in the control unit.

[0011] The production work W is prepared by correcting it to be shorter by 1 mm in total length before machining. That is, in this case, the finished target length dimension of the production work W is 1 m, and the production work W produced by correction is 999 mm.

Next, the production work W corrected in advance in this way is hardened. At this time, for example, when the work W is a cutting screw, as shown in FIGS. 5A and 5C, the quenching depth x is a predetermined depth (for example, x = 3). .2 mm), the elongation is zero, but tends to increase as the quenching depth x becomes deeper than the predetermined depth, and conversely, shrink as the quenching depth x becomes shallower than the predetermined depth.

Using this tendency, the reference elongation percentage, and the measured value of elongation by the length measuring device 953, the control unit performs the following feedback control during the moving quenching period to perform The quenching for W is automatically controlled.

The basic conditions are the same as the above-mentioned standard conditions. The power applied to the high-frequency heating coil 911 is 100 kW, and the moving speed v for moving the quenching mechanism 910 is 10 mm / sec. After the quenching of the work W is started under these basic conditions, the control unit calculates the elongation rate of the work W by measuring the elongation of the work W by a length measuring device 953 at a fixed span (time interval).

The control unit compares the elongation percentage with the reference elongation percentage (1 per mil). If the elongation percentage is not reached, the moving speed v is decreased, and if it is exceeded, the moving speed v is increased. Feedback control is performed so as to be as close as possible to the reference elongation rate.

If the moving speed v is reduced, the work W
(Amount of heating per unit area) is increased, thereby increasing the quenching depth, and the work W showing the tendency of FIG. 5 (A) is elongated (in some cases, the shrinkage is reduced), and the elongation rate is increased. Is large. On the other hand, when the moving speed v is increased, the amount of heating of the work W is reduced, whereby the quenching depth is reduced, and the amount of expansion of the work W having the tendency shown in FIG. 5A is reduced (shrinkage in some cases). , The elongation is small. That is, by adjusting the moving speed v, the elongation can be adjusted.
The feedback control is performed using this fact.

The feedback control is performed for the following reason. The work W has substantially the same material in the same lot, but still has some variation in the material. Further, even in the same lot, for example, when the sharpness of a cutting tool used for cutting is deteriorated, or when the margin for one cut is changed, the residual stress after the processing of the workpiece W is slightly different. If the feedback control is not performed, the moving speed v is kept constant at 10 mm / sec, and the influence of the variation and the difference in the residual stress appears as it is. This is because the pitch after quenching varies.

In addition, when quenching the next lot that should be the same material, the variation in the material between lots is often larger than the variation in the lot. This is because the variation in the length dimension of the work W after quenching is further increased. In addition,
When the lot is changed, it is possible to re-create the reference data again, and this may be done in some cases.

[0019]

However, in the conventional induction hardening apparatus, the quenching depth is 4.5 m, which is the center value (standard value) of the quenching specification, by the feedback control.
m, but the actual control is to set the length dimension of the work W after quenching (that is, the pitch after quenching) to the target finish length of the production work W. It is designed to match the dimensions (pitch after quenching). That is, the control does not include a specific means for making the quenching depth within the standard range.

As described above, the elongation of the work W is controlled by adjusting the moving speed v, adjusting the amount of heating, and finally adjusting the quenching depth. Therefore, in controlling the elongation of the work W, the quenching depth necessarily fluctuates. However, although the range of the variation of the quenching depth needs to be within the above-mentioned standard range of 4.5 ± 0.5 mm, there is a specific range such that the quenching depth falls within the above-mentioned standard range. No control was performed. Therefore, the quenching depth of the production work W may be out of the standard range.

In addition, the control of the elongation of the work W during the stop heating is not particularly performed. Therefore, since the heating amount during the stop heating was not controlled as during the moving heating, the quenching depth at the stop heating position was likely to be out of the standard range.

A main object of the present invention is to provide a long workpiece heat treatment apparatus capable of quenching a long workpiece to a quenching depth within a specified range while controlling elongation, and a length used in the apparatus. It is an object of the present invention to provide a method for controlling a heat treatment of a scale-shaped work.

[0023]

According to a first aspect of the present invention, there is provided a heat treatment apparatus for a long work, comprising: a high-frequency heating coil for heating a long work;
A power supply unit for supplying power to the high-frequency heating coil body, a moving mechanism for moving the high-frequency heating coil body along the work, a length measuring device for measuring the elongation of the entire length of the work being heated, and the length measuring device A control unit that controls the moving speed of the high-frequency heating coil body to control the amount of heating of the unheated portion of the workpiece by using the data of the elongation measured by the control unit. The same pre-data acquisition work as the production work has a predetermined hardening depth dc
Reference data of elongation measured when heat-treated
The power pc at that time, the moving speed vc of the high-frequency heating coil body at that time, and the quench depth at the power pc are the allowable maximum value dc + d2 and the allowable minimum value dc, respectively.
A storage unit for storing the moving speeds v _L and v _H obtained as −d1, and the power p of the storage unit as the power during the moving heating.
c, and a heating amount basic control unit for setting the moving speed at the start of moving heating to the moving speed vc; and data of the elongation of the production work measured by the length measuring device during moving heating and the storage unit. And a comparison control unit that changes the moving speed between the moving speeds v _L and v _H so as to be equal to the reference data.

According to a second aspect of the present invention, there is provided an elongated workpiece heat treatment apparatus, comprising: a high-frequency heating coil for heating a long workpiece; a power supply for supplying power to the high-frequency heating coil; A moving mechanism that moves the coil body along the work, a length measuring device that measures the elongation of the entire length of the work being heated, and heating of the work that has not been completed using the elongation data measured by the length measuring device. And a control unit for controlling the magnitude of the electric power to control the amount of heating of the portion, wherein the control unit is configured such that a pre-data acquisition work similar to a production work is previously set to a predetermined quenching depth dc. The reference data of the elongation measured at the time of heat treatment, the value of the power pc at that time, the moving speed vc of the high-frequency heating coil body at that time, and the quenching depth at the moving speed vc are allowed. Daine dc + d2, allowable minimum value dc-
a storage unit that stores the powers p _H and p _L that have become d1,
The power pc of the storage unit as power at the start of moving heating
And a heating amount basic control unit for causing the moving speed during the moving heating to be the moving speed vc, and data on the elongation of the production work measured by the length measuring device during the moving heating and the storage unit. A comparison control unit that compares the power with the reference data and changes the power between the powers p _H and p _L so as to be equal to the reference data.

According to a third aspect of the present invention, there is provided an apparatus for heat treating a long workpiece, comprising: a high-frequency heating coil for heating the long workpiece; a power supply for supplying power to the high-frequency heating coil; A moving mechanism that moves the coil body along the work, a length measuring device that measures the elongation of the entire length of the work being heated, and heating of the work that has not been completed using the elongation data measured by the length measuring device. A control unit for controlling the magnitude of the electric power or the moving speed of the high-frequency heating coil body to control the amount of heating of the portion, wherein the control unit is configured to perform a pre-data acquisition work similar to a production work in advance. Is subjected to heat treatment to a predetermined quenching depth dc, and reference data of elongation measured at the time, and the power pc at that time.
And the moving speed vc of the high-frequency heating coil at that time
And the moving speeds v _L and v _{H at} which the quenching depth at the power pc is the permissible maximum value dc + d2 and the permissible minimum value dc−d1, respectively, and the quenching depth at the moving speed vc is the permissible maximum value. dc + d2, minimum allowable value dc-d1
And a storage unit that stores the respective powers p _H and p _L, and supplies the power pc of the storage unit as the power at the start of the stop heating, and the power pc of the storage unit as the power during the moving heating. The heating amount basic control unit to be supplied, the data of the elongation of the production work measured by the length measuring device during the stop heating and the reference data of the storage unit are compared, and the reference data is made equal to the reference data. the power power p _H,
varied between p _L, and, as compared to the production for growth data of the workpiece measured by the measuring device during movement heating with the reference data of the storage unit becomes equal to the reference data The moving speed is set to the moving speed v _L , v _H
And a comparison control unit that changes between the two.

According to a fourth aspect of the present invention, there is provided an apparatus for heat treating a long workpiece, comprising: a high-frequency heating coil for heating the long workpiece; a power supply for supplying power to the high-frequency heating coil; A moving mechanism that moves the coil body along the work, a length measuring device that measures the elongation of the entire length of the work being heated, and heating of the work that has not been completed using the elongation data measured by the length measuring device. And a control unit for controlling the magnitude of the electric power to control the amount of heating of the portion, wherein the control unit is configured such that a pre-data acquisition work similar to a production work is previously set to a predetermined quenching depth dc. The reference data of the elongation measured at the time of heat treatment, the power pc at that time, the moving speed vc of the high-frequency heating coil body at that time, and the quenching depth at the moving speed vc are respectively allowable maximum values. dc + d2, the minimum allowable value dc-d1
And the storage unit for storing the respective powers p _H and p _L, and the power pc of the storage unit is supplied as the power at the start of the stop heating, and the moving speed during the moving heating is referred to as the moving speed vc. The heating amount basic control unit to be compared, the data of the elongation of the production work measured by the length measuring device during the stop heating and the moving heating and the reference data in the storage unit are compared, and become equal to the reference data. And a comparison control unit that changes the power between the powers p _H and p _L.

According to a fifth aspect of the present invention, in the method for controlling heat treatment of a long workpiece, the quenching depth of the long workpiece heated by the moving high-frequency heating coil is set to a predetermined range dc-.
This is a method for controlling the heat treatment of a long workpiece to be accommodated in d1 to dc + d2, in which a plurality of workpieces similar to a production workpiece are prepared as preliminary data acquisition workpieces. While the power supplied to the high-frequency heating coil body is kept constant during the moving heating, the moving speed of the high-frequency heating coil body is changed to an arbitrary constant value to perform a heat treatment, and a predetermined one of these pre-data acquisition works is performed. Of the quenching depth dc is obtained as reference data, and the predetermined quenching depth dc is obtained.
While the power pc and the moving speed vc are obtained, the moving speeds v _L , v at which the quench depth becomes the allowable maximum value dc + d2 and the allowable minimum value dc−d1, respectively, at the power pc. Acquire _H , the production work is the elongation dimension after heat treatment of the pre-data acquisition work,
When preparing a work having a length deducted from the finished target length dimension of the production work and performing heat treatment on the production work, the moving speed at the start of moving heating is set to the moving speed vc. During the heating, the elongation of the production work is measured for each predetermined moving distance of the high-frequency heating coil while supplying the power pc, and the data of the elongation is measured by the high-frequency heating coil in the preliminary data acquisition work. The moving speed is compared with the reference data after the body has moved the same distance, and the moving speed is set to the moving speed so that the elongation of the production work becomes equal to the reference data after the same data moving of the pre-data acquisition work. It is characterized in that it is changed between v _L and v _H.

According to a sixth aspect of the present invention, in the method for controlling heat treatment of a long workpiece, the quenching depth of the long workpiece heated by the moving high-frequency heating coil is set to a predetermined range dc-.
This is a method for controlling the heat treatment of a long workpiece to be accommodated in d1 to dc + d2, in which a plurality of workpieces similar to a production workpiece are prepared as preliminary data acquisition workpieces. While the moving speed of the high-frequency heating coil body is kept constant during the moving heating, the electric power supplied to the high-frequency heating coil body is changed to an arbitrary constant value to perform a heat treatment. Of the quenching depth dc is obtained as reference data, and the predetermined quenching depth dc is obtained.
While the acquiring power pc and the moving velocity vc of when it is, the hardening depth, respectively, in the movement speed vc allowed maximum dc + d2, the power becomes minimum allowable dc-d1 p _H, p _L , the production work is the elongation dimension after heat treatment of the pre-data acquisition work,
When preparing a work having a length subtracted from the finished target length dimension of the production work and performing heat treatment on the production work, the electric power at the start of moving heating is the electric power pc.
On the other hand, during moving heating, the moving speed is set to vc, and at every predetermined moving distance of the high-frequency heating coil, or
The elongation of the production work is measured every elapse of a predetermined time, and the elongation data is compared with the reference data after the high-frequency heating coil body moves the same distance or after the same time elapses in the pre-data acquisition work. In comparison, the power is set between the powers p _L and p _H so that the elongation of the production work becomes equal to the reference data after the same distance movement or the same time of the advance data acquisition work. It is characterized by changing.

According to a seventh aspect of the present invention, in the method for controlling heat treatment of a long workpiece, the quenching depth of the long workpiece heated by the moving high-frequency heating coil is set to a predetermined range dc-.
This is a method for controlling the heat treatment of a long workpiece to be accommodated in d1 to dc + d2, in which a plurality of workpieces similar to a production workpiece are prepared as preliminary data acquisition workpieces. The electric power supplied to the high-frequency heating coil body during the stop heating and the moving speed of the high-frequency heating coil body during the moving heating are each changed to an arbitrary constant value to perform the heat treatment. The data of the elongation of the material having a predetermined quenching depth dc is obtained as reference data, and the power pc and the moving speed v at the time of the predetermined quenching depth dc are obtained.
c, while the quenching depth at the power pc is the allowable maximum value dc + d2 and the allowable minimum value dc−d1, respectively.
It acquires each moving velocity becomes v _L, and v _H, wherein hardening depth, respectively, in the movement speed vc allowed maximum dc + d2, the power becomes minimum allowable dc-d1 p _H, and p _L, The production work is to prepare a work of a length obtained by subtracting the elongation dimension after heat treatment of the pre-data acquisition work from the finish target length dimension of the production work, and performing the heat treatment on the production work. In the meantime, the power at the start of the stop heating is set to the power pc, while the stop heating is performed, the elongation of the production work is measured every predetermined time, and the data of the elongation is used as the work for the advance data acquisition. The power is compared with the reference data after the lapse of the same time, and the power is set to the power p so that the elongation of the production work becomes equal to the reference data of the pre-data acquisition work after the lapse of the same time.
_L, varied between p _H, it is moving heat elongation of the production for workpiece measured for every predetermined travel distance of the high-frequency heating coil body while said power pc, the data of the elongation, the pre In the data acquisition work, the high-frequency heating coil body is compared with the reference data after the same distance movement, and the elongation of the production work is equal to the reference data after the same distance movement of the advance data acquisition work. Preferably, the moving speed is changed between the moving speeds v _L and v _H.

According to an eighth aspect of the present invention, in the heat treatment control method for a long workpiece, the quenching depth of the long workpiece heated by the moving high-frequency heating coil is set to a predetermined range dc-.
This is a method for controlling the heat treatment of a long workpiece to be accommodated in d1 to dc + d2, in which a plurality of workpieces similar to a production workpiece are prepared as preliminary data acquisition workpieces. While the moving speed of the high-frequency heating coil body during the moving heating is kept constant, the electric power supplied to the high-frequency heating coil body is changed to an arbitrary constant value during the stop heating and the moving heating, and the heat treatment is performed. Predetermined quenching depth dc of data acquisition work
Is obtained as reference data, and the power pc and the moving speed vc when the predetermined hardening depth dc is obtained, while the hardening depth is obtained at the moving speed vc. Is the maximum allowable value dc +
d2, each becomes minimum allowable dc-d1 power p _H, p _L
Acquire, the production work is prepared a work of a length obtained by subtracting the elongation dimension after heat treatment of the pre-data acquisition work from the finish target length dimension of the production work,
When performing the heat treatment on the production work, the power at the start of the stop heating is the power pc, and during the stop heating, the elongation of the production work is measured every elapse of a predetermined time. The data is compared with the reference data after the lapse of the same time in the work for obtaining preliminary data, and the elongation of the production work is equal to the reference data after the lapse of the same time of the work for obtaining preliminary data. To
The power is changed between the powers p _L and p _H , and during the moving heating, the moving speed is set to the moving speed vc, and at every predetermined moving distance of the high-frequency heating coil body, or every predetermined time, the production work is performed. Is measured, and the data of the elongation is compared with the reference data after the high-frequency heating coil body has moved the same distance or after the same time has elapsed in the pre-data acquisition work, and the elongation of the production work is the so pre-made after data same distance movement of obtaining a work or the reference data after the same time equal to, characterized in that changing the power between the power p _L, p _H.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A long workpiece heat treatment apparatus according to an embodiment of the present invention for realizing a long workpiece heat treatment control method of the present invention will be described below with reference to FIGS.
FIG. 1 is a schematic explanatory view showing a long workpiece heat treatment apparatus according to an embodiment of the present invention, and FIG. 2 is a diagram showing a pre-data acquisition workpiece used in the long workpiece heat treatment apparatus according to the embodiment of the present invention. FIG. 3 is a diagram showing a relationship between elapsed time after stop heating and elongation as a reference of the work, and FIG. 3 shows heating during a stop heating period in a work for obtaining preliminary data used in a long work heat treatment apparatus according to an embodiment of the present invention. FIG. 4 is a graph showing the relationship between the elapsed time, the elongation when the reference elongation and the power value of the workpiece are the maximum allowable value, and the elongation when the power value is the minimum allowable value. FIG. 4 shows an embodiment of the present invention. FIG. 5 is a diagram showing the relationship between the movement amount of the high-frequency heating coil body and the reference elongation of the work in the work for obtaining preliminary data used when the control unit of the long workpiece heat treatment apparatus according to another embodiment is used. Of the work It is a figure explaining the relation between penetration depth and elongation, and the same figure (A) is a relation figure between hardening depth and elongation when a work is a cutting screw, and the same figure (B) is a work with a rolled screw. FIG. 7C is a diagram illustrating the relationship between the quenching depth and the elongation in the case, and FIG.

The long workpiece heat treatment apparatus according to the embodiment of the present invention is an induction hardening apparatus 900 that uses a ball screw as a long workpiece W. This induction hardening device 900
Is a so-called moving quenching apparatus, a high-frequency heating coil 911 for heating the work W, a power supply unit D for supplying power to the high-frequency heating coil 911, and a cooling jacket for injecting a cooling liquid for quenching. Quenching mechanism 9 comprising
10, a moving mechanism 930 for moving the quenching mechanism 910 along the work W, and a rotation / elongation for turning the work W while having a length measuring device 953 for measuring the elongation of the entire length of the work W during heating. A control unit (not shown) that controls the magnitude of the electric power to control the amount of heating of the unheated portion of the work W using the detection mechanism 950 and the data on the elongation measured by the length measuring device 953. And

The high-frequency heating coil 911 is, for example, a so-called saddle-type high-frequency heating coil.

The power supply section D includes a current transformer 912 and a high-frequency oscillator 913, and can change the magnitude of electric power according to an instruction from the control section.

The quenching mechanism 910 having the high-frequency heating coil body 911 and the like is movably attached to a ball screw 931 of the moving mechanism 930 which will be described later.

The moving mechanism 930 includes a ball screw 931 installed in parallel with the workpiece W, and a motor 9 for rotating the ball screw 931.
32. The motor 932 is, for example, a servo motor.

The rotation / elongation detecting mechanism 950 includes a chuck 951 for holding one end of the work W for rotating the work W, and a motor 95 for rotating the chuck 951.
2, a pair of the chuck 951 and a length measuring device 95 for pressing the center of the other end of the work W and detecting the extension of the work W
And 3.

The control unit previously performs a heat treatment (pre-hardening) of a pre-data acquisition work similar to the real work W (hereinafter, the real work W is also simply referred to as “work W”) to a predetermined quenching depth dc. ), The power pc at that time, the moving speed vc of the high-frequency heating coil 911 at that time, and the quenching depth at the moving speed vc. Maximum value dc + d
2. a storage unit that stores the powers p _H and p _L that have become the permissible minimum values dc-d1, and the power pc of the storage unit is supplied as power at the start of stop heating, and the power during the moving heating is supplied. A heating amount basic control unit for setting the moving speed to the moving speed vc; and the length measuring device 95 during the stop heating and the moving heating.
3, comparing the data of the elongation of the production work W measured with the reference data in the storage unit, and changing the power between the powers p _H and p _L so as to be equal to the reference data. The control unit includes a control unit and a general control unit that performs other overall control.

The data stored in the storage unit of the control unit is as follows, for example.

The predetermined quenching depth dc is a target best value (standard value) of the quenching specification and is 4.5 mm.

The elongation reference data is obtained, for example, as follows. First, a plurality of works similar to the production work W are prepared as pre-data acquisition works.
For these pre-data acquisition works, the power supplied to the high-frequency heating coil 911 during stop heating and during the moving heating is set to an arbitrary constant while the moving speed of the high-frequency heating coil 911 during the moving heating is constant. Quenching is performed by changing the value. Of these pre-data acquisition works, the elongation data of the work having a predetermined quenching depth dc = 4.5 mm is used as reference data.

The reference data is obtained, for example, by calculating the value of the elongation (elongation rate) at every elapse of a predetermined time interval in the relationship diagram between the elapsed time after the stop heating and the elongation as the reference of the work shown in FIG. Is equivalent to The predetermined time interval is:
Assuming that the film extends 1 mm in 5 seconds during the stop heating period, for example, 0.2 seconds during the stop heating period. The predetermined time interval during the moving quenching period may be 0.2 seconds, but is set to another value, for example, 5 seconds. This is because the change in elongation during the moving quenching period is more gradual than during the stop heating period.

In FIG. 2, the elongation during the stop heating period is substantially linear plus, and the elongation during the moving quenching period temporarily changes to minus at the stage when the cooling liquid starts to be injected from the cooling jacket 914. After that, it becomes a substantially linear positive change. Further, the elongation after the completion of the heating becomes negative. Note that the relationship diagram of FIG. 2 corresponds to a case where the workpiece W is a cutting screw that has a positive elongation when the predetermined quenching depth dc is 4.5 mm [FIG. reference〕.

The power pc when quenching to a predetermined quenching depth of 4.5 mm and the high-frequency heating coil 911 at that time
Moving speed vc is pc = 100 kW, vc = 10 mm
/ Sec.

At the moving speed vc = 10 mm / sec, the quenching depths are each allowable maximum value dc + d2 = 4.5 + 0.5.
= 5.0 mm, minimum allowable value dc-d1 = 4.5-0.5
= 4.0 mm, the respective powers p _H and p _L are p _H = 100
Suppose + 20 = 120 kW and p _L = 100−20 = 80 kW. Here, d2 = d1 = 0.5 mm
(Of course, d2 may be different from d1). Further, the standard range (permissible range) of the quenching depth is 4.0 to 5.0 mm.

The induction hardening device 90 thus configured
The value of 0 is, for example, substantially quenched to a predetermined finish target length dimension by feedback control by the control unit as follows, and the quenching depth is also within a standard range (permissible range). It will fit within 0-5.0 mm.

As a preliminary preparation, as in the prior art, as the production work W, after the completion of quenching of the preliminary data acquisition work quenched to a predetermined quenching depth of 4.5 mm (provided that the work is completely A length obtained by subtracting the elongation dimension at the cold stage from the finish target length dimension of the production work is corrected and prepared in advance during machining.
That is, for example, assuming that the elongation dimension is 1 mm and the finish target length dimension of the production work W is 1 m, the production work W is prepared to be corrected to 999 mm in advance.

First, a production work W is set in the induction hardening apparatus 900. The high-frequency heating coil 911 is at the stop heating position. The operation of the induction hardening apparatus 900 during the stop heating period is as follows.

When the elapsed time from the start of heating (hereinafter, also simply referred to as “elapsed time”) is 0 seconds (ie, at the start of stop heating), pc = 100 k is applied to the high-frequency heating coil 911.
W power starts to be supplied. If the data of the elongation of the production work W when the elapsed time is 0.2 seconds is the same as the reference data when the same time has elapsed, the conventional power, that is, the power of 100 kW in this case is continuously supplied.

However, if the data of the elongation of the production work W is smaller than the reference data after the lapse of the same time, the power is reduced by 10 so that the data becomes equal to the reference data.
Large and changed to a value within the range of p _H = 120 kW than 0 kW. Also, if the data of the elongation of the production work W is larger than the reference data at the same time, the power is reduced by 1 so that the data becomes equal to the reference data.
The value is changed to a value smaller than 00 kW and within a range of p _L = 80 kW or more. In this case, the power is controlled within the power range satisfying the quenching specification (within the range of the broken line shown in FIG. 3), and the quenching depth falls within the standard range of 4.0 to 5.0 mm.

When the elapsed time is 0.4 seconds, the same control as that when the elapsed time is 0.2 seconds is performed, and the same control is performed until the elapsed time is 5.0 seconds during the stop heating period.

Since the moving heating period starts at an elapsed time of 5.0 seconds, the high-frequency heating coil body 911 moves at a moving speed v
The movement is started at c = 10 mm / sec. The moving speed vc = 10 mm / sec is constant during the moving heating period.

Since control is performed every 5 seconds during the moving heating period, the following control is performed when the elapsed time is 10 seconds. Also at the time of the elapsed time of 10 seconds, if the elongation data of the production work W at the time of the elapsed time of 10 seconds is the same as the reference data at the same time, the power at the time of the elapsed time of 5 seconds Is the next predetermined elapsed time (in this case, the elapsed time is 15 seconds)
Is supplied up to. However, if the data of the elongation of the production work W is smaller than the reference data, the power is set to a value larger than 100 kW and a value within the range of p _H = 120 kW or less so as to be equal to the reference data. change. Further, if the data of the elongation of the production work W is larger than the reference data, the electric power is set to be smaller than 100 kW and p _L so as to be equal to the reference data.
= Change to a value within the range of 80 kW or more. In this case as well, the quenching is controlled within the power range that satisfies the quenching specification, so that the quenching depth falls within the standard range of 4.0 to 5.0 mm.

During the moving heating period, the same control as described above is continuously performed. Therefore, by the control as described above,
The production work W is almost quenched to a predetermined finished target length dimension, and the quenching depth is also within a standard range of 4.0 to 5.0.
It will fit within 0 mm.

In the induction hardening apparatus 900 according to the embodiment of the present invention, the moving speed vc = 10 mm / sec is constant during the moving heating period. , The control may be performed for each predetermined moving distance of the high-frequency heating coil body 911. The predetermined moving distance is, for example, 50 mm [ie, 1
0 (mm / sec) × 5 (sec) = 50 mm]. Since the motor 932 is a servomotor, this moving distance is determined by, for example, how many times the motor 932 has rotated. On the other hand, since the control of the motor 932 is controlled by the control unit, the control unit always recognizes the moving distance. That is, the control unit can perform control for each of the predetermined moving distances.

By the way, in the induction hardening apparatus 900 according to the embodiment of the present invention, when controlling the quenching depth both during the stop heating period and during the moving heating period, the induction heating coil body 911 is used during both the periods. And the amount of heat applied to the production work W was changed to change the quenching depth.

Since the moving speed of the high-frequency heating coil body 911 is zero during the stop heating period, there is no means for changing the moving speed in order to change the heating amount for the production work W. That's why. Therefore, in order to change the heating amount for the work W during the stop heating period, changing the power supplied to the high-frequency heating coil 911 is an appropriate means.

On the other hand, during the moving heating period, the high-frequency heating coil 911 is used to change the heating amount for the work W.
A means for changing the power supplied to the device can be employed. Therefore, during the stop heating period and during the moving heating period, it is easier to perform the control by taking the same means.

However, during the moving heating period, the high-frequency heating coil 91
It is also possible to take a means for changing the moving speed of one. Therefore, in the induction hardening device 900 according to the embodiment of the present invention, the means for changing the power supplied to the high-frequency heating coil body 911 during the stop heating period is used as described above. Means for changing the moving speed of the high-frequency heating coil body 911 while keeping the power constant may be adopted.

When the means for changing the moving speed of the high-frequency heating coil body 911 during the moving heating period is used, the control unit operates as follows.

That is, the control unit sets the reference data of the elongation measured when the pre-data acquisition work similar to the production work W is heat-treated (quenched) to the predetermined quenching depth dc, and The power pc at that time, the moving speed vc of the high-frequency heating coil body 911 at that time, and the moving speed v at which the quench depth at the power pc is the allowable maximum value dc + d2 and the allowable minimum value dc-d1, respectively. _L, v _H and each power p _H consisting hardening depth allowable maximum dc + d2 respectively, and the allowable minimum value dc-d1 in the moving velocity vc,
a storage unit that stores p _L, and a heating amount basic control unit that supplies the power pc of the storage unit as power at the start of stop heating and supplies the power pc of the storage unit as power during moving heating. And the length measuring device 953 during stop heating.
The data of the elongation of the production work W measured by the above and the reference data of the storage unit are compared, and the power is changed between the powers p _H and p _L so as to be equal to the reference data, and Comparing the elongation data of the production work W measured by the length measuring device during the moving heating with the reference data in the storage unit, and changing the moving speed v so that the moving speed becomes equal to the reference data. _L, v is provided with a comparison control unit for changing between _H, and a general control unit for other overall control of.

Therefore, the control unit of the induction hardening apparatus 900 in the case of using the means for changing the moving speed stores “quenching at the power pc” in comparison with the case of using the means for changing the power. Depth is allowable maximum value dc +
d2, the moving speeds v _{L at} which the permissible minimum value dc−d1 has been reached,
v _H ”is additionally stored. Then, the heating amount basic control unit of the control unit “supplies the power pc of the storage unit as the power during the moving heating instead of setting the moving speed during the moving heating to the moving speed vc. Point,
The comparison control unit of the control unit compares the data of the elongation of the production work W measured by the length measuring device 953 during the moving heating with the reference data of the storage unit, and becomes equal to the reference data. as, (rather than changing the power) the moving speed is changed to a value between the value v _L and the value v _H of the storage unit "points.

Here, at the power pc = 100 kW, the quenching depths are respectively set to the permissible maximum value dc + d2 = 5.0.
mm, each of the moving speeds v _L and v _{H at which} the allowable minimum value dc−d 1 = 4.0 mm, v _L = 10−2 = 8 mm / sec, v _H
= 10 + 2 = 12 mm / sec.

Of the reference data, the reference data during the stop heating period is, of course, the same as that in the induction hardening apparatus 900 in the case where the power is changed during the stop heating period and the moving heating period. Become. On the other hand, the reference data during the moving heating period is obtained by calculating the value of the elongation for each predetermined moving distance in the relation diagram between the moving amount of the high-frequency heating coil body 911 and the elongation as the reference of the work shown in FIG. Is equivalent to In order to acquire the reference data, “the moving speed of the high-frequency heating coil 911 during the moving heating is kept constant, and the power supplied to the high-frequency heating coil 911 during the stop heating and the moving heating is arbitrary. Instead, the power supplied to the high-frequency heating coil body 911 during the stop heating and the moving speed of the high-frequency heating coil body 911 during the moving heating are respectively set to an arbitrary constant value. Value and heat-treat it. "
And it is sufficient.

The predetermined moving distance is, for example, 50 mm. Since the motor 932 is a servo motor as described above, the moving distance is determined by, for example, how many times the motor 932 has rotated. On the other hand, since the control of the motor 932 is controlled by the control unit, the control unit always recognizes the moving distance. That is, the control unit can perform control for each of the predetermined moving distances.

The starting point of the predetermined moving distance is the stop heating position shown in FIG. Control is performed every 50 mm from this stop heating position. However, the starting point of the substantial predetermined moving distance is the origin shown in FIG. This origin is a mechanical origin and does not change even if the type of the work W is changed. Therefore, in the case of every predetermined moving distance, the distance between the origin and the stop heating position is added. Since the chuck 951 and the like exist between the origin and the stop heating position,
It is a part that is not heated.

In the induction hardening apparatus 900 in the case of taking a means for changing the moving speed during the moving heating period,
The control during the stop heating period changes the power as described above. Therefore, the description is omitted. On the other hand, during the moving heating period, the moving speed is controlled as follows every 50 mm of the predetermined moving distance after the high-frequency heating coil body 911 starts moving.

The starting point and a position 50 mm from the starting point
And the moving speed v of the high-frequency heating coil body 911 is
The value is based on the previous power. That is, for example,
If the power (power at 5 seconds elapsed time) is 100 kW,
The moving speed v = vc = 10 mm / sec. In addition,
The power is 80 kW (= p_L), The moving speed v = v _H
= 12 mm / sec. In addition, the conventional power is 120 kW
(= P_H), The moving speed v = v_L= 8mm / sec
is there.

The following control is performed at a position 50 mm from the starting point. If the data of the elongation of the production work W at the position 50 mm from the start point is the same as the reference data after moving the same distance, the previous moving speed is maintained at the position 50 to 100 mm from the start point. .

However, if the elongation data of the production work W is smaller than the reference data, the moving speed is set to less than 10 mm / sec and v _L = 8 mm / Change to a value within seconds or more. Also, if the data of the growth of the production work W is
If it is larger than the reference data, the moving speed is changed to a value larger than 10 mm / sec and within a range of v _H = 12 mm / sec so as to be equal to the reference data.

At the position 100 mm from the start point, the same control as that at the position 50 mm from the start point is performed, and the same control is performed during the moving heating period. Therefore, during the moving heating period, the quenching depth is controlled within the range of the moving speed satisfying the quenching specification, so that the quenching depth of the production work W falls within the standard range of 4.0 to 5.0 mm.

In the induction hardening apparatus 900 according to the embodiment of the present invention, the quenching depth is controlled both during the stop heating period and during the moving heating period. If so, of course, the above control regarding the quenching depth during the stop heating period is not performed. That is, the same control as during the above-described moving heating period is performed only during the moving heating period. However, in the case of the induction hardening device that changes the power during the moving heating period, the power at the start of the moving heating is pc = 100 kW. The moving speed at the start of moving heating in the case of the induction hardening device that changes the moving speed during the moving heating period is v = vc = 10 mm.
/ Sec.

In the above control, a fixed time interval or distance interval is used. However, irregular time intervals or distance intervals may be used.

In the above, it has been described that the work W is a cutting screw and has the characteristics shown in FIG. However, there is a rolled screw as a type of the ball screw as a work. In the case of this rolled screw, when heated, as shown in FIG.

Therefore, the following method can be applied to the rolled screw. As preliminary work, as the actual work W, the elongation after the completion of quenching of the work for preliminary data acquisition quenched to a predetermined quenching depth of 4.5 mm (however, when the work is completely cooled). The length of the actual work W is subtracted from the finished target length of the production work W, and the length of the actual work W is corrected and prepared in advance. That is, for example, assuming that the elongation dimension is -1 mm and the finish target length dimension of the production work W is 1 m,
The production work W is prepared by correcting and forming it to 1001 mm in advance. Other than this, it is basically the same as the case of the induction hardening apparatus 900.

In the above, the long workpiece heat treatment apparatus has been described as an induction hardening apparatus, but other than this, a heat treatment apparatus for quenching and tempering may be used. In this case, basically, there are many configurations common to the induction hardening apparatus 900, and only a part is different. Therefore, only the different part will be described.

The heat treatment apparatus for quenching and tempering is the same as the induction hardening apparatus 900 shown in FIG. 1 but on the back side of the cooling jacket 914 (ie, on the opposite side of the high-frequency heating coil body 911 with the cooling jacket 914 interposed therebetween). In addition, a high-frequency heating coil body for tempering is added. Further, a power supply unit different from the power supply unit D is connected to the tempering high-frequency heating coil body. Further, the added high-frequency heating coil body for tempering and the another power supply unit are controlled by the control unit. Of course, low-frequency power suitable for tempering is supplied from the power supply unit to the tempering high-frequency heating coil body.

In the induction hardening apparatus 900, the reference data is “reference data of elongation measured when a work for obtaining preliminary data similar to the work W for production is hardened to a predetermined quenching depth dc”. In the heat treatment apparatus for quenching and tempering, a reference for elongation measured when a work for obtaining preliminary data similar to the work W for real production was quenched and tempered to a predetermined quenching depth dc. Data ".

Therefore, even in a heat treatment apparatus for quenching and tempering, the quenching depth can be controlled by the same control as that of the induction quenching apparatus 900.

Another heat treatment apparatus for quenching and tempering has the same configuration as the induction hardening apparatus 900, and is of a type in which the high-frequency heating coil 911 is also used for tempering. In the case of this type, the high-frequency heating coil body 911 is moved again after quenching. At this time, power having a lower output than that at the time of quenching is supplied to the high-frequency heating coil body 911 from the power supply unit D as tempering power. Therefore, the quenching depth can be controlled by the same control as that of the induction hardening apparatus 900 even in another heat treatment apparatus that performs quenching and tempering.

The work W is not limited to a ball screw, but may be any general long work. With the above-described method, the quenching depth can be within the standard range.

[0082]

As described above, according to the first aspect of the present invention,
The high-frequency heating coil body that heats the long workpiece, a power supply unit that supplies power to the high-frequency heating coil body, and moves the high-frequency heating coil body along the workpiece. A moving mechanism, a length measuring device that measures the elongation of the entire length of the work being heated, and using the data of the elongation measured by the length measuring device, to control the amount of heating of the unheated portion of the work by using the data. A control unit for controlling a moving speed of the high-frequency heating coil body, wherein the control unit measures when a work for pre-data acquisition similar to a work for production is heat-treated to a predetermined quenching depth dc in advance. Reference data of the elongation and the power pc at that time
And the moving speed vc of the high-frequency heating coil at that time
A storage unit for storing the moving speeds v _L and v _H at which the quenching depth at the power pc is the permissible maximum value dc + d2 and the permissible minimum value dc−d1, respectively; A heating amount basic control unit that supplies the power pc of the unit and sets the moving speed at the start of the moving heating to the moving speed vc, and data of the elongation of the production work measured by the length measuring device during the moving heating. And a comparison control unit that compares the reference speed with the reference data stored in the storage unit and changes the movement speed between the movement speeds v _L and v _H so as to be equal to the reference data.

Therefore, in the case of the long workpiece heat treatment apparatus according to claim 1 of the present invention, the electric power pc is supplied as electric power during the moving heating, and the moving speed at the start of the moving heating is changed to the moving speed vc. On the other hand, the data of the elongation of the production work measured by the length measuring device during the moving heating is compared with the reference data, and the moving speed v _L is set to be equal to the reference data. v
_Since it is changed between _H , the quenching depth is controlled so that the quenching depth does not fall outside the standard range during the moving heating period while the elongation is controlled. That is, this is a long workpiece heat treatment apparatus capable of quenching a long workpiece to a quenching depth within a specified range while controlling elongation.

According to a second aspect of the present invention, there is provided an elongated workpiece heat treatment apparatus, comprising: a high-frequency heating coil for heating a long workpiece; a power supply for supplying power to the high-frequency heating coil; A moving mechanism that moves the coil body along the work, a length measuring device that measures the elongation of the entire length of the work being heated, and heating of the work that has not been completed using the elongation data measured by the length measuring device. And a control unit for controlling the magnitude of the electric power to control the amount of heating of the portion, wherein the control unit is configured such that a pre-data acquisition work similar to a production work is previously set to a predetermined quenching depth dc. The reference data of the elongation measured at the time of heat treatment, the value of the power pc at that time, the moving speed vc of the high-frequency heating coil body at that time, and the quenching depth at the moving speed vc are allowed. Daine dc + d2, allowable minimum value dc-
a storage unit that stores the powers p _H and p _L that have become d1,
The power pc of the storage unit as power at the start of moving heating
And a heating amount basic control unit for causing the moving speed during the moving heating to be the moving speed vc, and data on the elongation of the production work measured by the length measuring device during the moving heating and the storage unit. A comparison control unit that compares the power with the reference data and changes the power between the powers p _H and p _L so as to be equal to the reference data.

Therefore, in the case of the long workpiece heat treatment apparatus according to the second aspect of the present invention, the electric power pc is supplied as electric power at the start of the moving heating, and the moving speed during the moving heating is changed to the moving speed vc. On the other hand, the elongation data of the production work measured by the length measuring device during the moving heating is compared with the reference data, and the electric powers p _H and p _L are made equal to the reference data. Therefore, while the elongation is controlled, the quenching depth is controlled so as not to be out of the specification range during the moving heating period. That is, this is a long workpiece heat treatment apparatus capable of quenching a long workpiece to a quenching depth within a specified range while controlling elongation.

According to a third aspect of the present invention, there is provided an elongated workpiece heat treatment apparatus, comprising: a high-frequency heating coil for heating a long workpiece; a power supply for supplying power to the high-frequency heating coil; A moving mechanism that moves the coil body along the work, a length measuring device that measures the elongation of the entire length of the work being heated, and heating of the work that has not been completed using the elongation data measured by the length measuring device. A control unit for controlling the magnitude of the electric power or the moving speed of the high-frequency heating coil body to control the amount of heating of the portion, wherein the control unit is configured to perform a pre-data acquisition work similar to a production work in advance. Is subjected to heat treatment to a predetermined quenching depth dc, and reference data of elongation measured at the time, and the power pc at that time.
And the moving speed vc of the high-frequency heating coil at that time
And the moving speeds v _L and v _{H at} which the quenching depth at the power pc is the permissible maximum value dc + d2 and the permissible minimum value dc−d1, respectively, and the quenching depth at the moving speed vc is the permissible maximum value. dc + d2, minimum allowable value dc-d1
And a storage unit that stores the respective powers p _H and p _L, and supplies the power pc of the storage unit as the power at the start of the stop heating, and the power pc of the storage unit as the power during the moving heating. The heating amount basic control unit to be supplied, the data of the elongation of the production work measured by the length measuring device during the stop heating and the reference data of the storage unit are compared, and the reference data is made equal to the reference data. the power power p _H,
varied between p _L, and, as compared to the production for growth data of the workpiece measured by the measuring device during movement heating with the reference data of the storage unit becomes equal to the reference data The moving speed is set to the moving speed v _L , v _H
And a comparison control unit that changes between the two.

Therefore, in the case of the long workpiece heat treatment apparatus according to claim 3 of the present invention, the power pc is supplied as the power at the time of starting the stop heating, and the power pc is supplied as the power during the moving heating. while for, compared to the growth in data of the production workpiece to be measured by the measuring device during stopping heating and the reference data, the said power to be equal to the reference data power p _H, the p _L And data of the elongation of the production work measured by the length measuring device during the moving heating is compared with the reference data, and the moving speed is set to be equal to the reference data. v _L , v _H , so that the elongation is controlled, during stop heating and during moving heating,
The quenching depth is controlled so as not to fall outside the standard range. That is, this is a long workpiece heat treatment apparatus capable of quenching a long workpiece to a quenching depth within a specified range while controlling elongation.

According to a fourth aspect of the present invention, there is provided an elongated workpiece heat treatment apparatus, comprising: a high-frequency heating coil for heating a long workpiece; a power supply for supplying power to the high-frequency heating coil; A moving mechanism that moves the coil body along the work, a length measuring device that measures the elongation of the entire length of the work being heated, and heating of the work that has not been completed using the elongation data measured by the length measuring device. And a control unit for controlling the magnitude of the electric power to control the amount of heating of the portion, wherein the control unit is configured such that a pre-data acquisition work similar to a production work is previously set to a predetermined quenching depth dc. The reference data of the elongation measured at the time of heat treatment, the power pc at that time, the moving speed vc of the high-frequency heating coil body at that time, and the quenching depth at the moving speed vc are respectively allowable maximum values. dc + d2, the minimum allowable value dc-d1
And the storage unit for storing the respective powers p _H and p _L, and the power pc of the storage unit is supplied as the power at the start of the stop heating, and the moving speed during the moving heating is referred to as the moving speed vc. The heating amount basic control unit to be compared, the data of the elongation of the production work measured by the length measuring device during the stop heating and the moving heating and the reference data in the storage unit are compared, and become equal to the reference data. And a comparison control unit that changes the power between the powers p _H and p _L.

Therefore, in the case of the long workpiece heat treatment apparatus according to claim 4 of the present invention, the power pc of the storage unit is supplied as the power at the start of the stop heating, and the moving speed during the moving heating is controlled. Is compared with the reference data in the storage section, while comparing the data of the elongation of the production work measured by the length measuring device during the stop heating and during the moving heating, and the same as the reference data. The power is changed between the powers p _H and p _L so that the quenching depth does not fall outside the specified range during the stop heating and the moving heating period while controlling the elongation. Is done. That is, this is a long workpiece heat treatment apparatus capable of quenching a long workpiece to a quenching depth within a specified range while controlling elongation.

The method for controlling the heat treatment of a long workpiece according to claims 5 to 8 of the present invention is basically realized by the apparatus for heat treating a long workpiece according to claims 1 to 4 of the present invention. Therefore, the effect is the same as that of the above-described long workpiece heat treatment apparatus according to claims 1 to 4 of the present invention.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing a long workpiece heat treatment apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a relationship between an elapsed time after stop heating and a reference elongation of a workpiece in a workpiece for pre-data acquisition used in a long workpiece heat treatment apparatus according to an embodiment of the present invention.

FIG. 3 is a diagram showing a state in which the heating elapsed time during the stop heating period and the reference elongation and power values of the workpiece for the pre-data acquisition workpiece used in the long workpiece heat treatment apparatus according to the embodiment of the present invention are the maximum allowable values. It is a relation diagram with the expansion when the value is a value, and the expansion when the value of the electric power is the allowable minimum value.

FIG. 4 is a diagram illustrating a moving amount of a high-frequency heating coil body and a reference of a work in a work for obtaining preliminary data used when a control unit of a long work heat treatment apparatus according to an embodiment of the present invention is used as another example. FIG.

FIG. 5 is a diagram for explaining the relationship between the quenching depth and the elongation of the work, and FIG. 5A is a diagram showing the relationship between the quenching depth and the elongation when the work is a cutting screw, and FIG. FIG. 3 is a diagram illustrating the relationship between the quenching depth and the elongation when the work is a rolled screw, and FIG. 3C is a diagram illustrating the quenching depth.

[Explanation of symbols]

 900 Induction hardening device (long workpiece heat treatment device) 911 High frequency heating coil body 912 Current transformer (part of power supply unit) 913 High frequency oscillator (part of power supply unit) 914 Cooling jacket 930 Moving mechanism 953 Length measuring device D power supply Department

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05B 6/06 311 H05B 6/06 311 6/10 371 6/10 371

Claims (8)

[Claims] 1. A high-frequency heating coil for heating a long workpiece, a power supply for supplying power to the high-frequency heating coil, a moving mechanism for moving the high-frequency heating coil along the workpiece, and a heating mechanism. A length measuring device for measuring the elongation of the entire length of the workpiece, and using the data on the elongation measured by the length measuring device, the high-frequency heating coil body is used to control the amount of heating of the unheated portion of the workpiece. A control unit for controlling the moving speed, wherein the control unit is configured to control the elongation of the elongation measured when the work for pre-data acquisition similar to the production work is heat-treated to a predetermined quenching depth dc in advance. Reference data, the power pc at that time, the moving speed vc of the high-frequency heating coil body at that time, and the power pc
And a storage unit for storing the moving speeds v _L and v _H at which the quenching depth has become the allowable maximum value dc + d2 and the allowable minimum value dc−d1, respectively, and the power pc of the storage unit as the power during the moving heating. And a heating amount basic control unit for causing the moving speed at the start of the moving heating to be the moving speed vc, and data of the elongation of the production work measured by the length measuring device during the moving heating and the storage unit. A long-range work heat treatment apparatus, comprising: a comparison control unit that compares the reference speed with the reference speed and changes the moving speed between the moving speeds v _L and v _H so as to be equal to the reference data. . 2. A high-frequency heating core for heating a long workpiece.
And a power supply for supplying power to the high-frequency heating coil body.
Move the source and the high-frequency heating coil along the workpiece
Movement mechanism to measure the elongation of the workpiece during heating
Measuring device and the elongation measured by this measuring device.
Using the data, add
A control unit for controlling the magnitude of the electric power to control the amount of heat;
And the control unit has the same configuration as the production work in advance.
Work to obtain a predetermined quenching depth dc
Elongation baseline data measured when processed and its
The value of the power pc at that time and the high-frequency heating at that time
In the moving speed vc of the coil body and the moving speed vc,
Quenching depth is allowable maximum value dc + d2, allowable minimum value respectively
Each power p that has become dc-d1_H, P_LAnd memorize
And the power of the storage unit as power at the start of moving heating.
The moving speed during moving heating while supplying force pc
A heating amount basic control unit that makes the moving speed vc;
Production work measured by the length measuring device during heating
Compare the elongation data with the reference data in the storage unit
And the power is set to be equal to the reference data.
Power p _H, P_LHaving a comparison control unit that changes between
A long-sized workpiece heat treatment apparatus, characterized in that: 3. A high-frequency heating core for heating a long workpiece.
And a power supply for supplying power to the high-frequency heating coil body.
Move the source and the high-frequency heating coil along the workpiece
Movement mechanism to measure the elongation of the workpiece during heating
Measuring device and the elongation measured by this measuring device.
Using the data, add
The magnitude of the electric power or the high frequency
A control unit for controlling the moving speed of the thermal coil body.
Therefore, the control unit previously executes the same advance data as the production work.
The workpiece for heat treatment is heat-treated to a predetermined quench depth dc.
The reference data for the elongation measured at
Force pc and the moving speed of the high-frequency heating coil at that time
The degree of quenching is allowed for the temperature vc and the power pc.
Each of which has the maximum capacity dc + d2 and the minimum allowable value dc-d1
Moving speed v_L, V _HAnd quenching at the moving speed vc
Depth is allowable maximum value dc + d2, allowable minimum value dc
−d1 each power p_H, P_LAnd a storage unit for storing
The power pc of the storage unit as the power at the start of the stop heating.
And, as electric power during moving heating,
A heating amount basic control unit for supplying the electric power pc;
The extension of the production work measured by the length measuring device during heat
And comparing the reference data with the reference data in the storage unit,
The power so that it is equal to the reference data.
p_H, P_LAnd the above measurement during the moving heating.
The data of the elongation of the production work
The reference data in the storage unit is compared with the reference data.
The moving speed so that it is equal to
v_L, V_HHaving a comparison control unit that changes between
A long workpiece heat treatment apparatus characterized by the above-mentioned. 4. A high-frequency heating coil for heating a long workpiece, a power supply for supplying power to the high-frequency heating coil, a moving mechanism for moving the high-frequency heating coil along the workpiece, and a heating unit. A length measuring device for measuring the elongation of the entire length of the workpiece, and using the data of the elongation measured by the length measuring device, the magnitude of the electric power is controlled in order to control the amount of heating of the unheated portion of the workpiece. A control unit for controlling, wherein the control unit is provided with reference data of elongation measured when a workpiece for pre-data acquisition similar to a production workpiece is heat-treated to a predetermined quenching depth dc in advance. The power pc at that time, the moving speed vc of the high-frequency heating coil body at that time, and the quenching depth at the moving speed vc are respectively the allowable maximum value dc + d2 and the allowable minimum value dc.
A storage unit for storing the powers p _H and p _L obtained as −d1, and supplying the power pc of the storage unit as the power at the start of the stop heating, and the moving speed during the moving heating to the moving speed. vc, the heating amount basic control unit, and comparing the data of the elongation of the production work measured by the length measuring device during the stop heating and the moving heating with the reference data of the storage unit, and the reference data And a comparison control unit that changes the power between the powers p _H and p _L so as to be equal to each other. 5. The quenching depth of a long workpiece heated by a moving high-frequency heating coil is set to a predetermined range dc-
This is a method for controlling the heat treatment of a long workpiece to be accommodated in d1 to dc + d2, in which a plurality of workpieces similar to a production workpiece are prepared as preliminary data acquisition workpieces. While the power supplied to the high-frequency heating coil body is kept constant during the moving heating, the moving speed of the high-frequency heating coil body is changed to an arbitrary constant value to perform a heat treatment, and a predetermined one of these pre-data acquisition works is performed. Of the quenching depth dc is obtained as reference data, and the predetermined quenching depth dc is obtained.
While the power pc and the moving speed vc are obtained, the moving speeds v _L , v at which the quench depth becomes the allowable maximum value dc + d2 and the allowable minimum value dc−d1, respectively, at the power pc. Acquire _H , the production work is the elongation dimension after heat treatment of the pre-data acquisition work,
When preparing a work having a length deducted from the finished target length dimension of the production work and performing heat treatment on the production work, the moving speed at the start of moving heating is set to the moving speed vc. During the heating, the elongation of the production work is measured for each predetermined moving distance of the high-frequency heating coil while supplying the power pc, and the data of the elongation is measured by the high-frequency heating coil in the preliminary data acquisition work. The moving speed is compared with the reference data after the body has moved the same distance, and the moving speed is set to the moving speed so that the elongation of the production work becomes equal to the reference data after the same data moving of the pre-data acquisition work. A method for controlling heat treatment of a long workpiece, wherein the method is varied between v _L and v _H. 6. A quenching depth of a long workpiece heated by a moving high-frequency heating coil body is set to a predetermined range dc-
This is a method for controlling the heat treatment of a long workpiece to be accommodated in d1 to dc + d2, in which a plurality of workpieces similar to a production workpiece are prepared as preliminary data acquisition workpieces. While the moving speed of the high-frequency heating coil body is kept constant during the moving heating, the electric power supplied to the high-frequency heating coil body is changed to an arbitrary constant value to perform a heat treatment. Of the quenching depth dc is obtained as reference data, and the predetermined quenching depth dc is obtained.
While the acquiring power pc and the moving velocity vc of when it is, the hardening depth, respectively, in the movement speed vc allowed maximum dc + d2, the power becomes minimum allowable dc-d1 p _H, p _L , the production work is the elongation dimension after heat treatment of the pre-data acquisition work,
When preparing a work having a length subtracted from the finished target length dimension of the production work and performing heat treatment on the production work, the electric power at the start of moving heating is the electric power pc.
On the other hand, during moving heating, the moving speed is set to vc, and at every predetermined moving distance of the high-frequency heating coil, or
The elongation of the production work is measured every elapse of a predetermined time, and the elongation data is compared with the reference data after the high-frequency heating coil body moves the same distance or after the same time elapses in the pre-data acquisition work. In comparison, the power is set between the powers p _L and p _H so that the elongation of the production work becomes equal to the reference data after the same distance movement or the same time of the advance data acquisition work. A method for controlling heat treatment of a long workpiece, wherein the method is changed. 7. The quenching depth of a long workpiece heated by a moving high-frequency heating coil is set to a predetermined range dc-
This is a method for controlling the heat treatment of a long workpiece to be accommodated in d1 to dc + d2, in which a plurality of workpieces similar to a production workpiece are prepared as preliminary data acquisition workpieces. The electric power supplied to the high-frequency heating coil body during the stop heating and the moving speed of the high-frequency heating coil body during the moving heating are each changed to an arbitrary constant value to perform the heat treatment. The data of the elongation of the material having a predetermined quenching depth dc is obtained as reference data, and the power pc and the moving speed v at the time of the predetermined quenching depth dc are obtained.
c, while the quenching depth at the power pc is the allowable maximum value dc + d2 and the allowable minimum value dc−d1, respectively.
It acquires each moving velocity becomes v _L, and v _H, wherein hardening depth, respectively, in the movement speed vc allowed maximum dc + d2, the power becomes minimum allowable dc-d1 p _H, and p _L, The production work is prepared by preparing a work having a length obtained by subtracting the elongation dimension after heat-treating the preliminary data acquisition work from the finish target length dimension of the production work, and performing a heat treatment on the production work. In the meantime, the power at the start of the stop heating is set to the power pc, while the stop heating is performed, the elongation of the production work is measured every predetermined time, and the data of the elongation is used as the work for the advance data acquisition. The power is compared with the reference data after the lapse of the same time, and the power is set to the power p so that the elongation of the production work becomes equal to the reference data of the pre-data acquisition work after the lapse of the same time.
_L, varied between p _H, it is moving heat elongation of the production for workpiece measured for every predetermined travel distance of the high-frequency heating coil body while said power pc, the data of the elongation, the pre In the data acquisition work, the high-frequency heating coil body is compared with the reference data after the same distance movement, and the elongation of the production work is equal to the reference data after the same distance movement of the advance data acquisition work. And a step of changing the moving speed between the moving speeds v _L and v _H. 8. The quenching depth of a long workpiece heated by a moving high-frequency heating coil is set to a predetermined range dc-
This is a method for controlling the heat treatment of a long workpiece to be accommodated in d1 to dc + d2, in which a plurality of workpieces similar to a production workpiece are prepared as preliminary data acquisition workpieces. While the moving speed of the high-frequency heating coil body during the moving heating is kept constant, the electric power supplied to the high-frequency heating coil body is changed to an arbitrary constant value during the stop heating and the moving heating, and the heat treatment is performed. Predetermined quenching depth dc of data acquisition work
Is obtained as reference data, and the power pc and the moving speed vc when the predetermined hardening depth dc is obtained, while the hardening depth is obtained at the moving speed vc. Is the maximum allowable value dc +
d2, each becomes minimum allowable dc-d1 power p _H, p _L
Acquire, the production work is prepared a work of a length obtained by subtracting the elongation dimension after heat treatment of the pre-data acquisition work from the finish target length dimension of the production work,
When performing the heat treatment on the production work, the power at the start of the stop heating is the power pc, and during the stop heating, the elongation of the production work is measured every elapse of a predetermined time. The data is compared with the reference data after the lapse of the same time in the work for obtaining preliminary data, and the elongation of the production work is equal to the reference data after the lapse of the same time of the work for obtaining preliminary data. To
The power is changed between the powers p _L and p _H , and during the moving heating, the moving speed is set to the moving speed vc, and at every predetermined moving distance of the high-frequency heating coil body, or every predetermined time, the production work is performed. Is measured, and the data of the elongation is compared with the reference data after the high-frequency heating coil body has moved the same distance or after the same time has elapsed in the pre-data acquisition work, and the elongation of the production work is The elongate shape, wherein the power is changed between the powers p _L and p _H so that the reference data after moving the same distance or after the same time of the advance data acquisition work becomes equal to the reference data. Workpiece heat treatment control method.