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 mounting a coil spring on a support member and fixing one end of the coil spring to the outer peripheral surface of a rotatable 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 the first shaft member to move one end of the coil spring to a predetermined location. Each 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 and supported by the support member 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 a heating system for hardening, for example, a coil spring. [Background technology]

[0002] Conventionally, quenching is performed in the process of manufacturing coil springs. Quenching is performed, for example, to improve mechanical properties. A known heating method for quenching is to connect electrodes to the ends of the coil spring and heat the spring by passing electricity through them (see, for example, Patent Document 1). In Patent Document 1, the coil spring is supported by a support plate and is heated in a horizontal position with the central axis of the coil spring oriented in a substantially horizontal direction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 61-30246 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the heating method disclosed in Patent Document 1, there are cases where after quenching, the gaps between the wire rods of the coil spring and the diameter of the coil formed by winding vary greatly.

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

[0006] In order to solve the above-mentioned problems and achieve the object, the heating method of the present invention is a heating method for quenching a coil spring, and includes a fixing step of placing the coil spring on a support member and fixing one end of the coil spring to the outer peripheral surface of a rotatable first shaft member and the other end to the outer peripheral surface of a second shaft member; a heating step of passing electricity through the first and second shaft members to heat the coil spring; and a rotation step of rotating the first shaft member to move one end of the coil spring to a predetermined position, wherein the 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 and supported by the support member are parallel to the straight line.

[0007] Furthermore, in the heating method according to the present invention, in the above invention, the rotating step rotates the first shaft member when the temperature of the coil spring reaches a set temperature that is set to a temperature equal to or higher than the transformation point temperature of a material forming the coil spring.

[0008] In addition, in the heating method according to the present invention, in the above invention, the fixing step fixes the coil spring at a position where a central axis of the coil spring is offset from the straight line.

[0009] Furthermore, the heating system of the present invention is a heating system for hardening a coil spring, comprising: a first shaft member that is rotatable around a rotation axis extending in the longitudinal direction and that grips one end of the coil spring; a second shaft member that extends in the longitudinal axis direction and that grips the other end of the coil spring; and a control device that controls the supply of electricity to the first and second shaft members and the rotation of the first shaft member, wherein the rotation axis of the first shaft member and the longitudinal axis of the second shaft member are positioned on the same straight line that forms 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, and the control device releases the rotation restriction on the first shaft member when heating of the coil spring begins, and moves one end of the coil spring to a predetermined position by the end of the heating treatment. [Effects of the Invention]

[0010] According to the present invention, it is possible to suppress variations in the gaps between the wire rods of the coil spring and variations in the diameter of the coil formed by winding. [Brief explanation of the drawings]

[0011] [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 illustrating 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 diagram showing a schematic configuration of a heating system according to a first modified example of the present invention. [Figure 5] FIG. 5 is a flowchart showing a heating method according to the second modification of the present invention. [Figure 6] FIG. 6 is a flowchart showing a heating method according to the third modification of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as "embodiments") will be described with reference to the accompanying drawings. Note that the drawings are schematic, and the relationship between the thickness and width of each part, the thickness ratio of each part, etc. may differ from the actual ones, and the drawings may also include parts with different dimensional relationships and ratios.

[0013] (Embodiment) FIG. 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 FIG. 1 is a system for quenching, for example, a coil spring 100. The heating system 1 includes 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 is rotated about a predetermined axis (here, N 100 ) and a wire is wound spirally around it.

[0014] The heating device 10 includes a first shaft member 11, a second shaft member 12, and a support member 13.

[0015] The first shaft member 11 has a rotation axis N passing through the center of the cylindrical shaft body 110 and extending parallel to the longitudinal direction. 11 The shaft body 110 rotates around the rotation axis N 11 The rotation mechanism is rotatable around the axis of rotation, and the rotation of the rotation mechanism is controlled by the control device 20. The rotation mechanism is configured using, for example, a motor and a clutch. Furthermore, the rotation of the rotation mechanism can be restricted electrically or mechanically under the control of the control device 20. Furthermore, first shaft member 11 is provided with spring holding portion 111 that is fixed to a side surface of shaft body 110 and holds one end of coil spring 100. Spring holding portion 111 is provided with gripping portion 112 that clamps one end of coil spring 100 between itself and the outer peripheral surface of shaft body 110. Spring holding portion 111 rotates integrally with shaft body 110.

[0016] The second shaft member 12 is rotated along the longitudinal axis N under the control of the control device 20. 12The second shaft member 12 extends in a cylindrical shape with the central axis N. The second shaft member 12 is provided with a spring holding 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 holding portion 121 is provided with a gripping portion 122 that clamps the other end of the coil spring 100 with the outer peripheral surface of the shaft body 120. The shaft body 120 is fixed to the longitudinal axis N. 12 In this case, spring holding portion 121 rotates integrally with shaft body 120.

[0017] Rotation axis N of the first shaft member 11 11 , and the longitudinal axis N of the second shaft member 12 12 The line extending one axis toward the other axis coincides with the other axis. That is, the rotation axis N 11 and longitudinal axis N 12 The axes N11 and N12 do not have to be on the same straight line as long as it does not interfere with the rotation control of the coil spring 100. In addition, in a state where the coil spring 100 is gripped by each gripping portion (grip portions 112, 122), the central axis N of the coil spring 100 100 is the rotation axis N 11 and longitudinal axis N 12 In Figure 1, the central axis N 100 and rotation axis N 11 and longitudinal axis N 12 This shows an example where the center axis N is offset. 100 and rotation axis N 11 and longitudinal axis N 12 The central axis N may be aligned with the center axis N. 100 and rotation axis N 11 and longitudinal axis N 12 When the center axis N is offset, the coil spring 100 100 The rotation occurs around an axis parallel to the center axis N and at a different position. 100 and rotation axis N 11 and longitudinal axis N 12 When the center axis N is on the same line, the coil spring 100 100 rotates around the In addition, the central axis N100 and rotation axis N 11 and longitudinal axis N 12 The angle with respect to the horizontal direction is set to between 0 and 30 degrees. This angle is set depending on the characteristics of the coil spring, etc. The horizontal direction here refers to the direction perpendicular to the direction of gravity (vertical direction).

[0018] Furthermore, shaft body 110 of first shaft member 11 and shaft body 120 of second shaft member 12 are formed using a conductive material. Furthermore, each shaft body and control device 20 are connected by an electric wire (not shown).

[0019] FIG. 2 is a diagram for explaining the configuration of the main parts of a heating system according to one embodiment of the present invention. FIG. 2 is a diagram for explaining the configuration and operation of a shaft body and a spring holding part. When shaft body 110 rotates, spring holding part 111 also rotates in conjunction with this rotation. At this time, shaft body 110 rotates along a rotation axis N. 11 For example, the spring holding portion 111 reciprocates around the reference position P S Position P when rotated clockwise with respect to R and the reference position P S Position P when rotated counterclockwise with respect to L When shaft body 110 and gripping portion 112 grip coil spring 100, the end of coil spring 100 also moves along the outer periphery of shaft body 110 as shaft body 110 rotates. The first shaft member 11 is configured so that the amount of rotation can be measured using an encoder or the like.

[0020] The support member 13 is a plate on which the coil spring 100 is placed and which supports the coil spring 100. The support member 13 may be configured to move up and down in the vertical direction depending on the positions of the first shaft member 11 and the second shaft member 12 and the size of the coil spring 100. The support member 13 may also be configured to support only a specific portion of the coil spring 100 (for example, the center portion of the coil spring 100).

[0021] Returning to FIG. 1, the control device 20 includes 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 input of various signals related to the operation of the heating system 1. The input unit 21 is configured using a keyboard, a mouse, a switch, a touch panel, and the like.

[0023] The output unit 22 displays images and outputs sounds and lights under the control of the control unit 25. The output unit 22 is configured using a display, a speaker, a light source, and the like.

[0024] The setting unit 23 sets the heating conditions, for example, based on setting information received by the input unit 21 or information stored in the storage unit 26. The setting unit 23 sets the heating temperature and heating time of the coil spring 100, the position of the gripping portion 112 after heating, and the amount of power to be applied to the shaft member.

[0025] The detection unit 24 detects the temperature of the coil spring 100. The detection unit 24 may also 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 has an electrical current control unit 251 and a rotation control unit 252. For example, when an instruction to start heating treatment is input via the input unit 21, the electrical current control unit 251 turns on electrical current to the first shaft member 11 and the second shaft member 12. The rotation control unit 252 controls the rotation of the first shaft member 11 during heating treatment.

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

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

[0029] Next, the heating process of the coil spring 100 by the heating system 1 will be described with reference to Fig. 3. Fig. 3 is a flowchart showing a heating method according to an embodiment of the present invention. The following description will be given assuming that each unit operates under the control of the control device 20.

[0030] First, coil spring 100 is set in heating device 10 (step S101). Specifically, one end of coil spring 100 is held between gripping portion 112 and shaft body 110, and the other end is held between gripping portion 122 and shaft body 120. As a result, both ends of coil spring 100 are fixed to first shaft member 11 and second shaft member 12.

[0031] After the coil spring 100 is set, the current control unit 251 starts current application to the first shaft member 11 and the second shaft member 12 (step S102). The current application control unit 251 starts current application control in response to a current application start instruction or the like received by the input unit 21. When current is applied, a current flows through the coil spring 100 via the first shaft member 11 and the second shaft member 12, generating heat. This heat heats the coil spring. The current application control unit 251 controls the flow of current 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] The rotation control section 252 also controls the rotation axis N of the first shaft member 11.11 The restriction on rotation around the rotation axis N is released (step S103). 11 The surroundings are free to rotate. The processes of steps S102 and S103 may be executed simultaneously, or step S103 may be executed first. Also, if the first shaft member 11 is in a freely rotatable state at the time of proceeding to step S103, step S103 does not need to be executed.

[0033] During the heat treatment, the coil spring 100 is deformed due to structural transformation, etc. At this time, the first shaft member 11 follows this deformation and rotates in the direction of the rotation axis N 11 This rotation allows the load acting on the coil spring 100 to be released when it is deformed.

[0034] Then, rotation control unit 252 determines whether the temperature of coil spring 100 has reached the set temperature (step S104). If rotation control unit 252 determines, based on the temperature detected by detection unit 24, that the temperature of coil spring 100 has not reached the set temperature (step S104: No), it repeats checking the temperature. On the other hand, if rotation control unit 252 determines that the temperature of coil spring 100 has reached the set temperature (step S104: Yes), the process 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 coil spring 100.

[0035] In step S105, rotation control unit 252 rotates shaft body 110 to move gripping portion 112 to a preset position. Here, the preset position is, for example, the position where coil spring 100 was attached before heating, or a position corresponding to the end position of coil spring 100 held by second shaft member 12.

[0036] Thereafter, the power supply control unit 251 stops power supply to the first shaft member 11 and the second shaft member 12, and ends the heating process (step S106). The timing of ending the energization and the timing of executing the rotation process may be simultaneous, or the rotation process may be executed first.

[0037] In the embodiment of the present invention described above, the ends of the coil spring are gripped and fixed to the outer peripheral surface of each shaft body, and coil spring 100 is electrically heated via the shaft body, with one of the shaft members being free to rotate during heating so that it rotates in response to the deformation of coil spring 100 caused by structural transformation. According to this embodiment, by discharging the load caused by the deformation of coil spring 100 during structural transformation caused by electrical heating and by moving the end positions to set positions when heating is completed, it is possible to suppress variations in the gaps between the wire rods of the coil spring (for example, gap S1 shown in FIG. 1 ) and variations in the diameter of the coil formed by winding (for example, coil diameter R1 shown in FIG. 1 ).

[0038] Furthermore, according to this embodiment, when the coil spring 100 reaches its transformation point temperature, the first shaft member 11 is rotated to move the end position of the coil spring 100 to an appropriate position, thereby further improving the shape accuracy.

[0039] (Variation 1) Next, a first modification of the embodiment of the present invention will be described with reference to Fig. 4. Fig. 4 is a diagram showing a schematic configuration of a heating system according to the first modification of the present invention. The heating system 1A according to the first modification includes a heating device 10A instead of the heating device 10. The control device 20 has the same configuration as in the embodiment, and therefore description thereof will be omitted.

[0040] The heating device 10A includes a first shaft member 11, a second shaft member 12, and a support member 13A. The first shaft member 11 and the second shaft member 12 are the same as those in the embodiment, and therefore a description thereof will be omitted.

[0041] The support member 13A supports the coil spring 100 by placing the coil spring 100 thereon. The support member 13A is made up of a plurality of rod-like members 131 that extend like rods and support a portion of the coil spring 100 at their tips. The support member 13A may be configured so that each rod-like member 131 moves up and down in the vertical direction depending on the positions of the first shaft member 11 and the second shaft member 12 and the size of the coil spring 100. The support member 13A may also be configured to support only a specific portion of the coil spring 100 (for example, the center of the coil spring 100).

[0042] The heating process of the coil spring 100 by the heating system 1A is carried out in the same manner as the flowchart shown in FIG.

[0043] In the present modified example 1 described above, the heating process is carried out in the same manner as in the embodiment, and therefore, by dissipating the load caused by deformation during the structural transformation of the coil spring 100 that occurs during electrical heating, and by moving the end positions to set positions at the end of heating, it is possible to suppress variations in the gaps between the wire rods of the coil spring and variations in the diameter of the coil formed by winding.

[0044] (Variation 2) Next, a second modification of the embodiment of the present invention will be described. The heating system according to the second modification is the heating system 1 according to the embodiment, and includes a measurement mechanism (not shown) that measures the temperature of the coil spring 100. Note that in the modification, the detection unit 24 will be described as detecting the energization time.

[0045] The heating process according to the second modification will be described with reference to Fig. 5. Fig. 5 is a flowchart showing the heating method according to the second modification.

[0046] First, similarly to steps S101 and S102 shown in FIG. 3, the coil spring 100 is set in the heating device 10 (step S201), and the current control unit 251 starts to supply current to the first shaft member 11 and the second shaft member 12 (step S202).

[0047] Thereafter, the rotation control unit 252 rotates the rotation axis N of the first shaft member 11. 11 During the heat treatment, the rotation restriction around the rotation axis N is released in accordance with the deformation of the coil spring 100 (step S203). 11 Rotate around.

[0048] Thereafter, the rotation control unit 252 determines whether the energization time has elapsed a preset set time (step S204). When the rotation control unit 252 determines that the energization time has not elapsed the set time based on the energization time detected by the detection unit 24 (step S204: No), the rotation control unit 252 repeats checking the energization time. On the other hand, when the rotation control unit 252 determines that the energization time has elapsed the set time (step S204: Yes), the process proceeds to step S205. The set time set at this time is, for example, the time required for the coil spring 100 to reach a temperature at which it is austenitized.

[0049] In step S205, rotation control section 252 rotates shaft body 110 to move the position of gripping section 112 to a preset position.

[0050] Thereafter, the power supply control unit 251 stops power supply to the rotating shaft (step S206).

[0051] In the present modified example 2 described above, the heating process is carried out in the same manner as in the embodiment, and therefore, by dissipating the load caused by deformation during the structural transformation of the coil spring 100 that occurs during electrical heating, and by moving the end positions to set positions at the end of heating, it is possible to suppress variations in the gaps between the wire rods of the coil spring and variations in the diameter of the coil formed by winding.

[0052] (Variation 3) Next, a third modification of the embodiment of the present invention will be described. The heating system according to the third modification is the heating system 1 according to the embodiment, and includes a measurement mechanism (not shown) that measures the temperature of the coil spring 100. In this modification, the detection unit 24 is described as detecting the amount of electric power (for example, the total amount of electric power since the start of energization).

[0053] The heating process according to the third modification will be described with reference to Fig. 6. Fig. 6 is a flowchart showing the heating method according to the third modification.

[0054] First, similarly to steps S101 and S102 shown in FIG. 3, the coil spring 100 is set in the heating device 10 (step S301), and the current control unit 251 starts to supply current to the first shaft member 11 and the second shaft member 12 (step S302).

[0055] Thereafter, the rotation control unit 252 rotates the rotation axis N of the first shaft member 11. 11 During the heat treatment, the rotation restriction around the rotation axis N is released in accordance with the deformation of the coil spring 100 (step S303). 11 Rotate around.

[0056] Thereafter, the rotation control unit 252 determines whether the amount of energized electric power has reached a preset set amount of electric power (step S304). When the rotation control unit 252 determines, based on the amount of energized electric power detected by the detection unit 24, that the amount of energized electric power has not reached the set amount of electric power (step S304: No), the rotation control unit 252 repeats checking the amount of energized electric power. On the other hand, when the rotation control unit 252 determines that the amount of energized electric power has reached the set amount of electric power (step S304: Yes), the process proceeds to step S305. The set amount of electric power set at this time is, for example, the amount of electric power (e.g., total amount of electric power) required for the coil spring 100 to reach a temperature at which it is austenitized.

[0057] In step S305, rotation control section 252 rotates shaft body 110 to move the position of gripping section 112 to a preset position.

[0058] Thereafter, the power supply control unit 251 stops power supply to the rotating shaft (step S306).

[0059] In the third modification described above, the heating process is carried out in the same manner as in the embodiment, and therefore, by dissipating the load caused by deformation during the structural transformation of the coil spring 100 that occurs during electrical heating, and by moving the end positions to set positions at the end of heating, it is possible to suppress variations in the gaps between the wire rods of the coil spring and variations in the diameter of the coil formed by winding.

[0060] Up to this point, the embodiments for carrying out the present invention have been described, but the present invention should not be limited to only the above-described embodiments. Note that in the embodiments, an example in which the second shaft member 12 does not rotate has been described, but the second shaft member 12 may be configured to rotate, or both the first shaft member 11 and the second shaft member 12 may be configured to be rotatable. When both shaft members are configured to be rotatable, for example, in step S105, at least one of the shaft members is rotated so that the position of the spring holding portion of one shaft member and the position of the spring holding portion of the other shaft member correspond to the design position.

[0061] In this way, the present invention can include various embodiments not described here, and various design changes can be made within the scope that does not deviate from the technical idea specified by the claims.

[0062] Furthermore, in the embodiment and modified examples, examples have been described in which the decision to stop or continue is made using any one of temperature, heating time, and power amount, but this is not limited to this, and control may be made by combining temperature, time, and power amount.

[0063] As described above, the heating method and heating system according to the present invention are suitable for suppressing variations in the gaps between wire rods of a coil spring and variations in the diameter of the coil formed by winding. [Explanation of symbols]

[0064] 1. 1A heating system 10, 10A heating device 11 First shaft member 12 2nd shaft member 13, 13A Support member 20 Control device 21 Input section 22 Output section 23 Setting section 24 Detector 25 Control Unit 26 Memory section 251 Power supply control unit 252 Rotation control unit 261 Heating condition storage section 262 Rotation condition memory section

Claims

1. A heating method for quenching a coil spring, comprising: a fixing step of placing the coil spring on a support member, and fixing one end of the coil spring to an outer circumferential surface of a rotatable first shaft member and the other end to an outer circumferential surface of a second shaft member; a heating step of energizing the first and second shaft members to heat the coil spring to a temperature equal to or higher than a transformation point temperature of a material forming the coil spring, and allowing the first shaft member to rotate freely in accordance with deformation of the coil spring; a rotating step of rotating the first shaft member to move one end of the coil spring to a preset position while the temperature of the coil spring is in a region equal to or higher than a transformation point temperature; Including, the axes of the first and second shaft members are positioned on the same straight line, and the straight line forms an angle of 0 to 30 degrees with respect to the horizontal direction; the central axis of the coil spring attached to the first and second shaft members and supported by the support member is parallel to the straight line; A heating method characterized by:

2. the rotating step rotates the first shaft member when the temperature of the coil spring reaches a set temperature that is set to a temperature equal to or higher than a transformation point temperature of a material forming the coil spring. The heating method according to claim 1 .

3. the fixing step fixes the coil spring at a position where a central axis of the coil spring is offset from the straight line; 3. The heating method according to claim 1 or 2.

4. A heating system for quenching a coil spring, comprising: a first shaft member that is rotatable about a rotation axis extending in the longitudinal direction and that grips one end of the coil spring; a second shaft member extending in the longitudinal axis direction and gripping 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 shaft member; Equipped with the rotation axis of the first shaft member and the longitudinal axis of the second shaft member are positioned on the same straight line, and the straight line forms an angle of 0 to 30 degrees with respect to the horizontal direction; the central axes of the coil springs attached to the first and second shaft members are parallel to the straight line; the control device heats the coil spring to a temperature equal to or higher than a transformation point temperature of a material forming the coil spring by energizing the coil spring, and releases the restriction on rotation of the first shaft member when heating of the coil spring begins, and moves one end of the coil spring to a preset position during a period when the temperature of the coil spring is in a range equal to or higher than the transformation point temperature. A heating system comprising:

Images