Heating method and heating system

Abstract

To provide a heating method and a heating system capable of suppressing dispersion of gaps between wires of a coil spring and dispersion of diameters of a coil formed by winding.SOLUTION: A heating method for hardening a coil spring includes a fixing step for fixing one end of a coil spring to the outer peripheral surface of a first shaft member and the other end to the outer peripheral surface of a second shaft member, a heating step for energizing the first and second shaft members to heat the coil spring, and a rotation step for rotating each of the first and second shaft members, while energizing the first and second shaft members. Each rotation axis of the first and second shaft members is located on the same straight line of an angle of 0 degree or more and 30 degrees or less to the horizontal direction. The coil spring fixed to the first and second shaft members has the central axis parallel to the straight line.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a heating method and heating system for, for example, quenching a coil spring. [Background technology]

[0002] Conventionally, hardening is performed in the process of manufacturing coil springs. Hardening is performed, for example, to improve mechanical properties. As a heating method for hardening, a method is known in which electrodes are connected to the ends of the coil spring and heated by the heat generated by passing an electric current through them (see, for example, Patent Document 1). In Patent Document 1, the coil spring is supported by a support plate and heated while placed horizontally with the central axis of the coil spring facing approximately horizontally. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 61-30246 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] However, in the heating method disclosed in Patent Document 1, after quenching, variations in the gaps between the wires of the coil spring and variations in the diameter of the coil formed by winding sometimes increased.

[0005] The present invention has been made in view of the above, and aims to provide a heating method and heating system that can suppress variations in the gaps between the wires of a coil spring and variations in the diameter of the coil formed by winding. [Means for solving the problem]

[0006] To solve the above-mentioned problems and achieve the objective, the present invention provides a heating method for quenching a coil spring, comprising: a fixing step of fixing one end of the coil spring to the outer circumferential surface of a first shaft member and the other end to the outer circumferential surface of a second shaft member; a heating step of energizing the first and second shaft members to heat the coil spring; and a rotation step of rotating the first and second shaft members respectively while the first and second shaft members are energized, wherein the rotation axes of the first and second shaft members are located on the same straight line forming an angle of 0 to 30 degrees with respect to the horizontal direction, and the central axes of the coil springs attached to the first and second shaft members are parallel to the straight line.

[0007] Furthermore, the heating method according to the present invention is characterized in that, in the above invention, the heating step and the rotation step are stopped based on a set temperature which is set to a temperature equal to or higher than the transformation point temperature of the material forming the coil spring.

[0008] Furthermore, the heating method according to the present invention is characterized in that, in the above invention, the rotation step rotates the first and second shaft members at a rotation speed set based on the variation in the gap between the wires of the coil spring and / or the variation in the coil diameter of the coil spring.

[0009] Furthermore, the heating method according to the present invention is characterized in that, in the above invention, the fixing step is to fix the coil spring at a position in which the central axis of the coil spring is offset with respect to the straight line.

[0010] Moreover, the heating system according to the present invention is a heating system for quenching a coil spring, and includes a first shaft member that is rotatable about a central axis extending in the longitudinal direction and grips one end of the coil spring, and a second shaft member that is rotatable about a central axis extending in the longitudinal direction and grips the other end of the coil spring, and a control device that controls energization to the first and second shaft members and rotation of the first and second shaft members. The first and second shaft members are characterized in that their respective rotation axes are located on the same straight line and form an angle of 0 to 30 degrees with respect to the horizontal direction, and the central axis of the coil spring attached to the first and second shaft members is parallel to the straight line.

Advantages of the Invention

[0011] According to the present invention, there is an effect that variations in the gaps between the wire rods of the coil spring and variations in the diameter of the coil formed by winding can be suppressed.

Brief Description of the Drawings

[0012] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a heating system according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram for explaining the configuration of a main part of a heating system according to an embodiment of the present invention. [Figure 3] FIG. 3 is a flowchart showing a heating method according to an embodiment of the present invention. [Figure 4] FIG. 4 is a flowchart showing a heating method according to Modification 1 of the present invention. [Figure 5] FIG. 5 is a flowchart showing a heating method according to Modification 2 of the present invention.

Modes for Carrying Out the Invention

[0013] Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as "embodiments") will be described with reference to the attached drawings. Note that the drawings are schematic, and the relationship between the thickness and width of each part, the ratio of the thickness of each part, etc., may differ from reality, and there may be parts where the dimensional relationships and ratios differ between drawings.

[0014] (Embodiment) Figure 1 is a diagram showing a schematic configuration of a heating system according to one embodiment of the present invention. The heating system 1 shown in Figure 1 is a system for hardening, for example, a coil spring 100. The heating system 1 comprises a heating device 10 that holds and heats the coil spring 100, and a control device 20 that controls the heating device 10. The coil spring 100 has a predetermined axis (here, N 100 It is made by spirally winding wire around a base.

[0015] The heating device 10 comprises a first shaft member 11 and a second shaft member 12.

[0016] The first shaft member 11, under the control of the control device 20, has a shaft N that passes through the center of the cylindrical shaft body 110 and extends parallel to the longitudinal direction. 11 It rotates around the (rotation axis). The first shaft member 11 is also provided with a spring retaining portion 111 which is fixed to the side surface of the shaft body 110 and holds one end of the coil spring 100. The spring retaining portion 111 is provided with a gripping portion 112 which sandwiches one end of the coil spring 100 between itself and the outer circumferential surface of the shaft body 110. The spring retaining portion 111 rotates integrally with the shaft body 110.

[0017] The second shaft member 12, under the control of the control device 20, passes through the center of the cylindrical shaft body 120 and extends parallel to the longitudinal direction of shaft N 12 It rotates around the (rotation axis). The second shaft member 12 is also provided with a spring retaining portion 121 that is fixed to the side surface of the shaft body 120 and holds the other end of the coil spring 100. The spring retaining portion 121 is provided with a gripping portion 122 that sandwiches the other end of the coil spring 100 between itself and the outer circumferential surface of the shaft body 120. The spring retaining portion 121 rotates integrally with the shaft body 120.

[0018] Axis N of the first shaft member 11 11 and axis N of the second shaft member 12 12 are such that a straight line extending one axis toward the other axis coincides with the other axis. That is, axis N 11 and axis N 12 are located on the same straight line. As long as there is no problem in the rotation control of the coil spring 100, axis N 11 and axis N 12 do not have to be on exactly the same straight line. Also, in a state where the coil spring 100 is gripped by each gripping part (gripping parts 112, 122), the central axis N of the coil spring 100 100 is parallel to axis N 11 and axis N 12 respectively. In FIG. 1, an example in which the central axis N 100 is offset from axis N 11 and axis N 12 is shown, but the central axis N 100 and axis N 11 and axis N 12 may be arranged to coincide with each other. When the central axis N 100 is offset from axis N 11 and axis N 12 the coil spring 100 rotates around axes that are parallel to the central axis N 100 and are located at different positions from each other. On the other hand, when the central axis N 100 is on the same straight line as axis N 11 and axis N 12 the coil spring 100 rotates around the central axis N 100 . Note that the angle between the central axis N 100 and axis N 11 and axis N 12 is set to 0 or more and 30 degrees or less with respect to the horizontal direction. This angle is set according to the characteristics of the coil spring and the like. Here, the horizontal direction means a direction perpendicular to the direction of gravity (vertical direction).

[0019] Furthermore, the shaft body 110 of the first shaft member 11 and the shaft body 120 of the second shaft member 12 are formed using a conductive material. In addition, each shaft body and the control device 20 are connected by wires (not shown).

[0020] Figure 2 is a diagram illustrating the configuration of the main parts of a heating system according to one embodiment of the present invention. Figure 2 is a diagram illustrating the configuration and operation of the shaft body and the spring retaining part. Although Figure 2 illustrates the first shaft member 11, the second shaft member 12 operates similarly. When the shaft body 110 rotates, the spring retaining part 111 also rotates in conjunction with this rotation. At this time, the shaft body 110 reciprocates at a rotation angle θ under the control of the control device 20. The spring retaining part 111 is at a reference position P S In contrast, position P is obtained by rotating clockwise by an angle of rotation θ / 2. R And, reference position P S In contrast, position P is obtained by rotating it counterclockwise by an angle of rotation θ / 2. L The two parts reciprocate. When the shaft body 110 and the gripping part 112 grip the coil spring 100, the end of the coil spring 100 also moves along the outer circumference of the shaft body 110 as the shaft body 110 rotates. The rotation angle θ can be set according to the type of coil spring 100, for example, within a range of 90 degrees (±45 degrees) to 360 degrees. Furthermore, each shaft member is configured to allow measurement of rotational amount using an encoder or the like.

[0021] Returning to Figure 1, the control device 20 comprises an input unit 21, an output unit 22, a setting unit 23, a detection unit 24, a control unit 25, and a storage unit 26.

[0022] The input unit 21 receives various signals related to the operation of the heating system 1. The input unit 21 is configured using a keyboard, mouse, switch, touch panel, etc.

[0023] The output unit 22, under the control of the control unit 25, displays images and outputs sound and light. The output unit 22 is composed of a display, speaker, light source, etc.

[0024] The setting unit 23 sets the heating conditions. Based on setting information received by the input unit 21 and information stored in the storage unit 26, for example, the setting unit 23 sets the heating temperature and heating time of the coil spring 100, the rotation angle of the shaft member, the rotation speed of the shaft member, and the amount of power supplied to the shaft member.

[0025] The detection unit 24 detects the temperature of the coil spring 100. Alternatively, the detection unit 24 may be configured to detect the temperature of each shaft member.

[0026] The control unit 25 controls the operation of each component of the heating system 1. The control unit 25 also includes an energization control unit 251 and a rotation control unit 252. The energization control unit 251, for example, turns on the energization to the first shaft member 11 and the second shaft member 12 when it receives an instruction input to start the heating process via the input unit 21. The rotation control unit 252 rotates the first shaft member 11 and the second shaft member 12 in a pattern set during the heating process.

[0027] The setting unit 23, the detection unit 24, and the control unit 25 are each composed of processors such as a CPU (Central Processing Unit) or various arithmetic circuits that perform specific functions, such as an ASIC (Application Specific Integrated Circuit).

[0028] The memory unit 26 stores programs for the control unit 25 to perform various operations (for example, programs to be executed during heat treatment). The memory unit 26 also includes a heating condition memory unit 261 that stores heating conditions when quenching the coil spring 100, as well as programs and parameters for the heat treatment, and a rotation condition memory unit 262 that stores rotation conditions when controlling the rotation of the coil spring 100, as well as programs and parameters for rotation control. The memory unit 26 is configured using volatile memory, non-volatile memory, or a combination thereof. For example, the memory unit 26 is configured using RAM (Random Access Memory), ROM (Read Only Memory), etc.

[0029] Next, the heating treatment of the coil spring 100 by the heating system 1 will be explained with reference to Figure 3. Figure 3 is a flowchart of a heating method according to one embodiment of the present invention. Hereinafter, it will be explained that each part operates under the control of the control device 20.

[0030] First, the coil spring 100 is set in the heating device 10 (step S101). Specifically, one end of the coil spring 100 is gripped by the gripping part 112 and the shaft body 110, and the other end is gripped by the gripping part 122 and the shaft body 120. In this way, both ends of the coil spring 100 are fixed to the first shaft member 11 and the second shaft member 12.

[0031] After setting the coil spring 100, the power supply control unit 251 starts supplying power to the first shaft member 11 and the second shaft member 12 (step S102). The power supply control unit 251 starts power supply control as a trigger for a power supply start instruction received by the input unit 21. When power is supplied, current flows through the first shaft member 11 and the second shaft member 12 to the coil spring 100, causing it to generate heat. This heat heats the coil spring. The power supply control unit 251 controls the current supplied to the first shaft member 11 and the second shaft member 12 so that the heating temperature of the coil spring 100 rises to the heating temperature set by the setting unit 23.

[0032] Furthermore, the rotation control unit 252 starts the rotation of the first shaft member 11 and the second shaft member 12 at the same time as the power supply control is started (step S103). The rotation control unit 252 rotates the shaft bodies 110 and 120 at the set rotational speed and rotational angle. The rotation control unit 252 rotates the shaft bodies 110 and 120 in synchronous operation. Here, for example, the rotational speed is set based on the variation in the gap between the wires of the coil spring 100 and / or the variation in the coil diameter of the coil spring 100. The timing of the start of rotation may be simultaneous with the start of power supply, or it may be after a set time has elapsed since the start of power supply.

[0033] The energization control unit 251 determines whether the temperature of the coil spring 100 has reached the set temperature (step S104). If the energization control unit 251 determines, based on the temperature detected by the detection unit 24, that the temperature of the coil spring 100 has not reached the set temperature (step S104: No), it repeats the temperature check. On the other hand, if the energization control unit 251 determines that the temperature of the coil spring 100 has reached the set temperature (step S104: Yes), it proceeds to step S105. Here, the set temperature is set to a temperature equal to or higher than the transformation point temperature of the material forming the coil spring 100.

[0034] In step S105, the power supply control unit 251 terminates the supply of power to each shaft member.

[0035] When the power supply is terminated, the rotation control unit 252 rotates the shaft bodies 110 and 120 to move the gripping parts 112 and 122 to a preset position, and the heating process is terminated (step S106). Here, the preset position is, for example, a position for transporting the coil spring 100 to the next process after the heating process. Specifically, a position is set where the transport arm can easily grasp the coil spring 100. The timing of the end of power supply and the end of rotation may be simultaneous, or the rotation may be stopped first.

[0036] In the embodiments of the present invention described above, the ends of the coil springs are gripped and fixed to the outer circumferential surface of each shaft body, and the shaft members are rotated while current is supplied to the coil springs 100 via the shaft bodies, thereby heating the coil springs 100 under rotation. According to this embodiment, by rotating the coil springs 100 during heating to ensure uniform heating of the coil springs, variations in the gaps between the wires of the coil springs and variations in the diameter of the coils formed by winding can be suppressed.

[0037] (Variation 1) Next, Modification 1 of the present invention will be described with reference to Figure 4. The heating system according to Modification 1 is the same as the heating system according to the embodiment, so its description will be omitted. Figure 4 is a flowchart of the heating method according to Modification 1 of the present invention. Hereinafter, it will be described assuming that each part operates under the control of the control device 20. In this modification, it will be described assuming that the detection unit 24 detects the energization time.

[0038] In the modified example 1, the coil spring 100 is set in the heating device 10 in the same manner as in steps S101 to S103 shown in Figure 3, and the first shaft member 11 and the second shaft member 12 are energized and rotation is started (steps S201 to S203).

[0039] Subsequently, the energization control unit 251 determines whether the energization time has elapsed for a preset time (step S204). Based on the energization time detected by the detection unit 24, if the energization control unit 251 determines that the energization time has not elapsed for the preset time (step S204: No), it repeats the check of the elapsed time. On the other hand, if the energization control unit 251 determines that the energization time has elapsed for the preset time (step S204: Yes), it proceeds to step S205. The preset time set at this time is, for example, the time required for the coil spring 100 to reach the temperature at which it becomes austenitized.

[0040] In step S205, the power supply control unit 251 terminates the supply of power to each shaft member.

[0041] When the power supply is terminated, the rotation control unit 252 rotates the shaft bodies 110 and 120 to move the gripping portions 112 and 122 to a preset position, and terminates the heating process (step S206). The timing of the end of power supply and the end of rotation may be simultaneous, or the rotation may be stopped first.

[0042] In the modified example 1 described above, similar to the embodiment, the ends of the coil springs are gripped and fixed to the outer circumferential surface of each shaft body, and the shaft members are rotated while current is supplied to the coil springs 100 through the shaft bodies, thereby heating the coil springs 100 under rotation. According to this modified example 1, by rotating the coil springs 100 during heating to ensure uniform heating of the coil springs, variations in the gaps between the wires of the coil springs and variations in the diameter of the coils formed by winding can be suppressed.

[0043] (Modification 2) Next, a second modification of the present invention will be described with reference to Figure 5. The heating system in the second modification is the same as the heating system in the embodiment, so its description will be omitted. Figure 5 is a flowchart showing the heating method according to the second modification of the present invention. Hereinafter, it will be described that each part operates under the control of the control device 20. In the second modification, it will be described that the detection unit 24 detects the amount of power supplied (for example, the total amount of power supplied from the start of power supply).

[0044] In the modified example 2, the coil spring 100 is set in the heating device 10 in the same manner as in steps S101 to S103 shown in Figure 3, and the first shaft member 11 and the second shaft member 12 are energized and rotation is started (steps S301 to S303).

[0045] Subsequently, the power supply control unit 251 determines whether the amount of power supplied has reached a preset power amount (step S304). Based on the amount of power supplied detected by the detection unit 24, if the power supply control unit 251 determines that the amount of power supplied has not reached the preset power amount (step S304: No), it repeats the check of the amount of power supplied. On the other hand, if the power supply control unit 251 determines that the amount of power supplied has reached the preset power amount (step S304: Yes), it proceeds to step S305. The preset power amount set at this time is, for example, the amount of power required to reach the temperature at which the coil spring 100 becomes austenitized (for example, the total power).

[0046] In step S305, the power supply control unit 251 terminates the supply of power to each shaft member.

[0047] When the power supply is terminated, the rotation control unit 252 rotates the shaft bodies 110 and 120 to move the gripping portions 112 and 122 to a preset position, and terminates the heating process (step S306). The timing of the end of power supply and the end of rotation may be simultaneous, or the rotation may be stopped first.

[0048] In the modified example 2 described above, similar to the embodiment, the ends of the coil springs are gripped and fixed to the outer circumferential surface of each shaft body, and the shaft members are rotated while current is supplied to the coil springs 100 via the shaft bodies, thereby heating the coil springs 100 under rotation. According to this modified example 2, by rotating the coil springs 100 during heating to ensure uniform heating of the coil springs, variations in the gaps between the wires of the coil springs and variations in the diameter of the coils formed by winding can be suppressed.

[0049] While embodiments for carrying out the present invention have been described so far, the present invention should not be limited to the embodiments described above. In the embodiments, examples in which the gripping portions 112 and 122 are located on the upper part of each shaft body have been illustrated (see Figure 2, etc.), but since the position of the ends differs depending on the number of turns of the coil spring 100, the position of the gripping portions 112 and 122 may differ depending on the shape and number of turns of the coil spring 100 they hold (for example, the reference position P S ) will change.

[0050] Furthermore, while the embodiments and modifications described an example in which the movement reciprocates around a reference position, that is, the rotational movement is repeated with the direction of rotation reversed, the invention is not limited to this, and for example, a configuration in which the movement is rotated in the same direction may also be used.

[0051] Furthermore, although examples were described in which each shaft member rotates in perfect synchronization in the embodiments and modifications, they may also be configured to rotate in accordance with the deformation of the coil spring 100 due to heating.

[0052] Furthermore, while the embodiments and modifications described examples of determining whether to stop or continue using temperature, heating time, or power consumption, the control is not limited to these, and a combination of temperature, time, and power consumption may also be used.

[0053] Thus, the present invention may include various embodiments not described herein, and various design modifications can be made without departing from the technical idea specified by the claims.

[0054] As described above, the heating method and heating system according to the present invention are suitable for suppressing variations in the gaps between the wires of a coil spring and variations in the diameter of the coil formed by winding. [Explanation of symbols]

[0055] 1. Heating System 10 Heating device 11 First shaft member 12 2nd shaft member 20 Control device 21 Input section 22 Output section 23. Settings Section 24 Detection unit 25 Control Unit 26 Memory section 251 Power supply control unit 252 Rotation Control Unit 261 Heating condition storage section 262 Rotation Condition Storage Unit

Claims

1. A heating method for quenching coil springs, A fixing step involves fixing one end of a coil spring to the outer circumferential surface of a first shaft member and the other end to the outer circumferential surface of a second shaft member, A heating step of energizing the first and second shaft members and heating the coil spring to a temperature above the transformation point temperature of the material forming the coil spring, With the first and second shaft members energized, a rotation step is performed to rotate the first and second shaft members, respectively. Includes, The rotation axes of the first and second shaft members intersect with respect to the horizontal at an angle of 0 to 30 degrees. The coil springs fixed to the first and second shaft members are held in a state of non-contact with anything other than the first and second shaft members. The central axes of the coil springs attached to the first and second shaft members are parallel to the axis of rotation. A heating method characterized by the following features.

2. The heating step and the rotation step are stopped based on a set temperature that is set to a temperature above the transformation point temperature of the material forming the coil spring. The heating method according to feature 1.

3. The rotation step involves rotating the first and second shaft members within a predetermined range of rotation angles. The heating method according to feature 1.

4. The fixing step involves fixing the coil spring at a position where the central axis of the coil spring is offset with respect to the rotation axis. The heating method according to feature 1 or 2.

5. The rotation axes of the first and second shaft members are located on the same straight line, and the rotation axes are at an angle of 0 to 30 degrees with respect to the horizontal direction. The heating method according to feature 1.

6. A heating system for hardening coil springs, A first shaft member that is rotatable around a central axis extending in the longitudinal direction and grips one end of a coil spring, A second shaft member that is rotatable around a central axis extending in the longitudinal direction and grips the other end of the coil spring, A control device that controls the supply of current to the first and second shaft members and the rotation of the first and second shaft members, Equipped with, The control device heats the coil spring to a temperature above the transformation point temperature of the material forming the coil spring by applying current, The first and second axis members are such that their respective axes of rotation intersect the horizontal direction at an angle of 0 to 30 degrees. The first and second shaft members hold the fixed coil spring in a state where it is not in contact with anything other than the first and second shaft members. The central axes of the coil springs attached to the first and second shaft members are parallel to the axis of rotation. A heating system characterized by the following features.

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