WO2017159935A1

WO2017159935A1 - Hollow coil spring manufacturing method

Info

Publication number: WO2017159935A1
Application number: PCT/KR2016/009439
Authority: WO
Inventors: 김진영; 박익수; 김종형; 이실군
Original assignee: 대원강업 주식회사
Priority date: 2016-03-18
Filing date: 2016-08-25
Publication date: 2017-09-21
Also published as: KR101719151B1

Abstract

The present invention relates to a hollow coil spring manufacturing method. The purpose of the present invention is to provide a hollow coil spring manufacturing method wherein, in connection with manufacturing a coil spring using a hollow member, the manner of processing ends of the hollow member is improved such that the durability of the hollow coil spring can be improved compared with that according to the prior art. To this end, the present invention provides a hollow coil spring manufacturing method characterized by comprising the steps of: fixing a hollow member to a first chuck and fixing a finish member to a second chuck (S10); maintaining the first and second chucks in proximity with each other such that the finish member is forced against an end of the hollow member and rotating at least one of the first and second chucks, thereby generating frictional heat (S20); bringing the first and second chucks in closer proximity such that the hollow member and the finish member are more tightly forced against each other, thereby coupling the hollow member and the finish member, when parts of contact between the finish member and the hollow member are melted by the frictional heat occurring between the finish member and the hollow member, thereby sealing one end of the hollow member (S30); repeating the steps S10 to S30 such that the finish member is coupled to the other end of the hollow member and seals the same (S40); removing burrs formed on the parts of coupling between the hollow member and the finish member after the step S30 or S40 (S50); heating a coupled body configured by installing the finish member on both ends of the hollow member (S60); and helically winding the coupled body that has been heated through the step S60, thereby forming a coil spring (S70).

Description

Hollow coil spring manufacturing method

The present invention relates to a hollow coil spring manufacturing method, and more particularly to manufacturing a coil spring using a hollow member to improve the processing method for the end of the hollow member to increase the endurance life of the coil spring It relates to a hollow coil spring manufacturing method.

In general, the coil spring is formed by winding a spring steel wire in a spiral structure, and can perform various functions by mitigating vibration or shock or accumulating energy while compressing or tensioning, and thus, various daily necessities, industrial equipment, and automobiles. Widely used in various articles.

On the other hand, in the conventional manufacturing of the coil spring used for the vehicle suspension, although it has been manufactured using a solid spring steel wire, in accordance with the trend of lighter weight of the vehicle is increasing interest in the hollow coil spring manufactured by using a hollow member have.

The hollow coil spring is a hollow spring steel wire, that is, due to the characteristics of being manufactured using the hollow member, foreign matter is likely to flow into the coil spring during the manufacturing process or use process, in particular, when water is introduced into the coil There is a problem that the durability life of the spring is significantly reduced.

On the other hand, Patent Document 1 discloses a method of sealing the end of the hollow member used to manufacture the hollow coil spring.

In the method disclosed in Patent Document 1, the rolling jig is rotated while the end of the hollow member is in close contact with the rolling jig so that friction heat is generated between the hollow member and the rolling jig, and the end of the hollow member is heated by the frictional heat. Pressing the hollow member in the direction of the rolling jig in the process to close the end of the hollow member in a manner that induces a deformation in which the end portion of the hollow member is rolled into the hollow portion.

The sealing method as described above is to induce a deformation in the end of the hollow member to be sealed by itself, there is no need for a separate member and has the advantage of sealing the end of the hollow member through a simple process, Due to the change in mechanical properties with the end of the hollow member deformed by frictional heat, there is a problem in that the end portion of the hollow coil spring is easily corroded, thereby increasing the risk of cracking or breakage.

In addition, when the deformation amount is not uniform along the circumference of the hollow member in the deformation process in which the end portion of the hollow member is rolled inward, there is a problem that the gap is generated in the closed end, the probability of failure is increased.

(Prior art document)

(Patent Document 1) Published Patent Publication 10-2012-0037591 (2012.04.20.Publication)

The present invention has been made in consideration of the above problems, and an object of the present invention is to improve the processing method for the end of the hollow member in the manufacture of the coil spring using the hollow member compared with the conventional service life of the hollow coil spring It is to provide a hollow coil spring manufacturing method to be improved.

The present invention to achieve the object as described above and to perform the problem for removing the conventional defects is to fix the hollow member to the first chuck, and to fix the solid finish member to be coupled to the hollow member to the second chuck Step S10; Generating friction heat between the finishing member and the hollow member by rotating at least one of the first and second chucks while the first and second chucks are in close proximity to each other so that the finishing member is in close contact with the end of the hollow member. S20); When the contact portion between the finishing member and the hollow member is melted by frictional heat generated between the finishing member and the hollow member, the hollow member and the finishing member are brought closer to each other so that the hollow member and the finishing member are in close contact with each other. Sealing one end of the hollow member by combining (S30); Repeating the steps S10 to S30 to close and seal the closing member to the other end of the hollow member (S40); After step S30 or S40, removing the burr formed in the coupling portion of the hollow member and the finishing member (S50); Heating the assembly consisting of finishing members installed at both ends of the hollow member (S60); It provides a hollow coil spring manufacturing method comprising a; and (S70) to form a coil spring wound around the spiral heated through the step S60.

Meanwhile, in the hollow coil spring manufacturing method, the hollow member and the finishing member may be made of the same material or made of different materials.

Meanwhile, in the hollow coil spring manufacturing method, the step S10 may include a process of processing the side facing the end of the hollow member to the same size and shape as the end shape of the hollow member among the side surfaces of the finishing member. have.

On the other hand in the hollow coil spring manufacturing method, the step S60, the first heating step (S61) for heating the finishing member coupled to both ends of the hollow member; And a second heating step S62 of heating the hollow member and the finishing member as a whole after the heating of the finishing member is completed through the step S61.

Meanwhile, in the hollow coil spring manufacturing method, the step S60 is performed by a plurality of heating furnaces arranged in a structure spaced apart from each other along the moving path of the assembly, the step S61 is the two heating furnaces disposed in the front It is made to stop for a predetermined time in a state in which the closing member is coupled to both ends of the hollow member in the state, and the step S62 is completed after the step S61, the assembly is sequentially placed on the remaining heating furnace disposed on the movement path It may be made to via.

In addition, in the hollow coil spring manufacturing method, the step S60 is made of a resistance heating by sending a current directly to the assembly, the step S61 is to install a pair of electrodes at each end of the assembly of the hollow member It is made in such a way to flow the current to the finishing member located at both ends, the step S62 is to install one electrode at one end of the assembly, the other electrode is installed at the other end to send the current to the assembly as a whole Can be made.

Meanwhile, in the hollow coil spring manufacturing method, the step S61 consists of heating the finishing member at a temperature of 300 ° C. or more and less than 700 ° C., and the step S62 is heating the assembly to a temperature of 700 ° C. or more and less than 1100 ° C. Can be done.

According to the present invention having the above characteristics, since both ends of the hollow member are sealed in such a manner as to couple the solid finishing member to the open ends of the hollow member through friction welding, both ends of the hollow member It can be expected that the effect can be sealed stably.

In addition, the hollow member and the finishing member is composed of different materials, but considering the corrosion progresses at both ends of the coil spring by configuring the finishing member with a corrosion-resistant material, it can improve the durability life of the coil spring You can expect the effect.

In addition, in the heating step made before the coiling of the hollow member, the heating is performed by dividing into a primary heating step of heating the finishing members installed at both ends of the hollow member and a secondary heating step of heating the hollow member and the finishing member as a whole. By doing so, there is an effect that can prevent a defect that can occur during the coiling process due to lack of heating of the finishing member.

1 is a process diagram of a hollow coil spring manufacturing method according to a preferred embodiment of the present invention,

2 is a cross-sectional view of a structure of a finishing member according to the present invention;

3 is a process diagram of step S60 according to an embodiment of the present invention,

4 is a process diagram of step S60 according to another embodiment according to the present invention.

(Explanation of the sign)

M: binder 10: hollow member

20: finishing member 101: first chuck

102: second chuck 110: heating furnace

120: transfer means

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, if it is determined that the detailed description of the related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 is a process diagram of a hollow coil spring manufacturing method according to a preferred embodiment of the present invention, Figure 2 shows a cross-sectional view of the structure of the finishing member according to the present invention.

Hollow coil spring manufacturing method according to the present invention is to fix the hollow member 10 to the first chuck 101, solid finishing member 20 to be coupled to the hollow member 10, the second chuck 102 Fixing to (S10); At least one chuck of the first chuck 101 and the second chuck 102 is placed in a state in which the first and

second chucks

101 and 102 are close to each other such that the closing member 20 is in close contact with the end of the hollow member 10. Rotating to generate friction heat between the finishing member 20 and the hollow member 10 (S20); When the contact portion of the finishing member 20 and the hollow member 10 is melted by frictional heat generated between the finishing member 20 and the hollow member 10, the hollow member 10 and the finishing member 20 are more melted. Sealing one end of the hollow member 10 by combining the first and

second chucks

101 and 102 so as to be in close contact with the hollow member 10 and the finishing member 20 (S30); Removing burrs formed at the coupling portion of the hollow member 10 and the finishing member 20 (S40); Repeating the steps S10 to S40 to couple and close the closing member 20 to the other end of the hollow member 10 (S50); Heating the hollow members (10) in which both ends are sealed (S60); And forming a coil spring by spirally winding the hollow member 10 heated through the step S60 (S70).

The step S10 is a step of installing a hollow member 10 cut to a length for manufacturing a coil spring, and a solid finish member 20 for sealing both ends of the hollow member 10 to the friction welding equipment. As a result, the hollow member 10 is fixed to the first chuck 101 provided in the friction welding equipment, and the finishing member 20 is fixed to the second chuck 102 provided in the friction welding equipment.

For reference, the first chuck 101 and the second chuck 102 is disposed to have a structure facing on the friction welding equipment, at least one chuck of the first chuck 101 and the second chuck 102 is rotated. This structure is possible, and at least one of the first chuck 101 and the second chuck 102 is configured to have a structure capable of moving in a direction approaching or away from the remaining chuck.

On the other hand, in the case of friction welding equipment for implementing the hollow coil spring manufacturing method according to a preferred embodiment of the present invention, the second chuck 102 is fixed to the finishing member 20 has a rotatable structure, the hollow member 10 The first chuck 101 to be fixed) is configured to have a structure that is movable toward or away from the second chuck 102, and the friction welding equipment of such a structure is already widely used. More detailed description thereof will be omitted.

On the other hand, the hollow member 10 and the finishing member 20 may be made of the same material or a different material, preferably the hollow member 10 is made of spring steel used for the manufacture of the coil spring In consideration of the progress of corrosion at the end of the coil spring during use, the finishing member 20 is constructed using a material of enhanced corrosion resistance.

For example, when the hollow member 10 is made of SAE9254 spring steel, the finishing member 20 is made of a dissimilar material excellent in corrosion resistance than the SAE9254 spring steel.

In addition, in order to prevent the friction surface from being heated uniformly due to the difference in the area of the friction surface that the hollow member 10 and the finishing member 20 face each other, that is, the friction surface of the finishing member 20, that is, The side facing the end of the hollow member 10 may be processed into the same size and shape as the end shape of the hollow member 10, the step S10 may include a process of processing the finishing member 20.

For reference, in FIG. 2, the groove 21 having the same inner diameter as the inner diameter of the hollow member 10 is processed at the central portion of the side surface of the finishing member 20 having the same outer diameter as the outer diameter of the hollow member 10. Disclosed is a structure in which a side of the hollow member 10 and a side of the hollow member 10 are matched.

The step S20 is a step of generating friction heat between the hollow member 10 and the finishing member 20, the first chuck 101 and the second so that the ends of the hollow member 10 and the finishing member 20 in close contact with each other. The chuck 102 is brought into close proximity, and the hollow member 10 and the finishing member 20 are rubbed by rotating at least one of the first chuck 101 and the second chuck 102.

On the other hand, in the preferred embodiment of the present invention, the hollow member 10 and the closing member 20 in close contact with the movement of the first chuck 101, the closing member 20 through the rotation of the second chuck 102 Induce the friction between the hollow member 10 and the finishing member 20 in a manner to rotate the.

The step S30 is to press the hollow member 10 and the finishing member 20 to substantially join the hollow member 10 and the finishing member 20, the hollow member 10 through the step S20 and When the contact portion of the finishing member 20 is heated and melted, the second member 102 is moved in a direction close to the first chuck 101 so that the hollow member 10 and the finishing member 20 are in close contact with each other. It will consist of.

For reference, step S30 may be made while the closing member 20 is rotated, or after ending the rotation of the closing member 20, one end of the hollow member 10 through this step S30 is closed.

The step S40 is a step of removing a burr formed in a structure protruding outside the junction of the hollow member 10 and the finishing member 20, and the hollow member 10 and the finishing member 20 through the step S30. After the coupling is made, it may be made by a cutting device provided in the friction welding equipment.

On the other hand, the S40 step is to proceed in a manner to remove the burrs formed on both ends of the hollow member 10 in one process after the closing member 20 is coupled to both ends of the hollow member 10 through the S50 step. It may be.

The step S50 is a step of installing another finishing member 20 at the opposite end of the hollow member 10 is closed and the closing member 20 is installed at one end, consisting of repeating the steps S10 to S40 You lose.

That is, the hollow member 10 is fixed to the first chuck 101 in a state in which one end of the hollow member 10 is turned upside down so that the opposite end thereof is opened toward the first chuck 101 and the second member is fixed to the first chuck 101. In the state where the new finishing member 20 is fixed to the chuck 102 by friction welding the hollow member 10 and the finishing member 20 through the operation of the first and

second chucks

101 and 102, the opposite side of the hollow member 10 is fixed. Sealing of the end is made.

The step S60 is a step of heating the assembly (M) consisting of the finishing member 20 is installed at both ends of the hollow member 10 to the temperature required for the coiling operation, according to a preferred embodiment of the present invention, the Step S60 is a first heating step (S61) for heating the finishing member 20 coupled to both ends of the hollow member 10, and after the heating for the finishing member 20 through the step S61 is completed, the hollow member 10 and the second heating step (S62) for heating the finishing member 20 as a whole.

3 shows a process diagram of step S60 according to an embodiment of the present invention.

The step S60 according to an embodiment of the present invention may be made by a plurality of heating furnaces 110 are arranged in a structure spaced apart from each other along the movement path of the assembly (M). For reference, the heating furnace 110 may be an induction heating method of heating a material through induction heating or a heating furnace of heating a material by using heat generated during combustion of a fuel. .

More specifically, the step S61 made by the heating furnace 110 may be performed by the two heating furnaces 110 disposed at the very front with respect to the path in which the assembly M moves.

That is, the closing member 20 provided at both ends of the assembly (M) in the process of moving the assembly (M) moving by the conveying means 120, such as a roller along a predetermined path is disposed in the front of the path When each is located inside the two heating furnaces 110, the first heating step (S61) for heating the finishing member 20 is made by maintaining the assembly (M) in the stopped state for a predetermined time as it is. do.

In addition, the step S61 is preferably heating the finishing member 20 to a temperature of less than 300 ℃ 700 ℃. This is a problem that when heating the finishing member 20 to a temperature of less than 300 ℃, it is difficult to heat the temperature of the finishing member 20 suitable for coiling operation in the second heating step (S62), 700 ℃ In the case of heating to the above temperature, there is a disadvantage that the productivity is lowered due to unnecessary increase in the heating time, energy is wasted.

On the other hand, the step S62 made by the heating furnace 110 is located in front of the rest of the heating path 110, that is, the assembly (M) in the assembly (M) heated the finishing member 20 through the step S61. The remaining heating furnace 110 except for the two heating furnace 110 is made to move so as to pass through the combination (M) sequentially.

In the S62 step, it is preferable to heat the binder M to a temperature of 700 ° C. or more and less than 1100 ° C. The temperature range of the 700 ~ 1100 ℃ is a temperature range suitable for the coiling operation of the hollow member 10, if lower than the temperature range is likely to cause a failure during the coiling operation, higher than the temperature range unnecessary There is a disadvantage in that productivity and energy waste due to the increase in the heating time.

According to another embodiment of the present invention, the step S60 may be made of a resistance heating method of directly flowing a current through the assembly M.

More specifically, the step S61 made by the resistance heating method is provided with a pair of electrodes (131, 132) at each end of the assembly (M), respectively, direct current to the finishing member 20 located at both ends of the assembly (M) It can be made in a way to flow, through which to heat the finishing member 20 to a temperature of less than 300 ℃ 700 ℃.

On the other hand, in the step S62 made by the resistance heating method, one electrode 141 is installed at one end of the assembly M, and another electrode 142 is installed at the other end to the other electrode from the other electrode. It can be made in a manner that flows a current, through which to heat the assembly (M) to a temperature of 700 ℃ or more below 1100 ℃.

The step S70 is a step consisting of processing the combined body (M) heated through the step S60 in the form of a spiral using the coiling equipment, and already developed and used in various ways coiling equipment, hollow according to the present invention Since coiling equipment of a special structure is not required in coiling the member, a more detailed description of step S70 will be omitted.

Hollow coil spring processed in the shape of a spiral through the above steps is made into a real product through a post-treatment process such as heat treatment, short peening and painting like a general coil spring.

On the other hand, in the case of the hollow coil spring manufacturing method according to the present invention, by applying a separate closing member 20 to both ends of the hollow member 10 in a manner to seal both ends of the hollow member 10, the hollow member ( Not only can the end of 10) be stably sealed, there is an advantage of improving the problems or improving the characteristics of the hollow coil spring through the selection of the material of the finishing member 20.

The present invention is not limited to the above-described specific preferred embodiments, and various modifications can be made by any person having ordinary skill in the art without departing from the gist of the present invention claimed in the claims. Of course, such changes will fall within the scope of the claims.

Claims

Fixing the hollow member to the first chuck and fixing the solid finishing member to be coupled to the hollow member to the second chuck (S10);

Generating friction heat between the finishing member and the hollow member by rotating at least one of the first and second chucks while the first and second chucks are in close proximity to each other so that the finishing member is in close contact with the end of the hollow member. S20);

When the contact portion between the finishing member and the hollow member is melted by frictional heat generated between the finishing member and the hollow member, the hollow member and the finishing member are brought closer to each other so that the hollow member and the finishing member are in close contact with each other. Sealing one end of the hollow member by combining (S30);

Repeating the steps S10 to S30 to close and seal the closing member to the other end of the hollow member (S40);

After step S30 or S40, removing the burr formed in the coupling portion of the hollow member and the finishing member (S50);

Heating the assembly consisting of finishing members installed at both ends of the hollow member (S60); And

Hollow coil spring manufacturing method characterized in that consisting of; (S70) to form a coil spring wound spirally heated the heated through the step S60.
The method according to claim 1,

Hollow coil spring manufacturing method, characterized in that the hollow member and the finishing member made of the same material.
The method according to claim 1,

Hollow coil spring manufacturing method characterized in that the hollow member and the finishing member made of different materials
The method according to claim 1,

Said step S10 comprises a step of processing the side of the finishing member, the side facing the end of the hollow member to the same size and shape as the end shape of the hollow member.
The method according to claim 1,

The step S60,

A first heating step (S61) of heating a finishing member coupled to both ends of the hollow member; And

And a second heating step (S62) of heating the hollow member and the finishing member as a whole after the heating of the finishing member is completed through the step S61.
The method according to claim 5,

The step S60 is made by a plurality of heating furnaces arranged in a structure spaced apart from each other along the movement path of the assembly,

The step S61 is to stop for a predetermined time in a state in which the finishing member coupled to both ends of the hollow member is positioned in the two heating furnaces disposed in the front, the step S62 is the assembly after the step S61 Hollow coil spring manufacturing method comprising the step of sequentially passing through the remaining heating furnace disposed on the movement path.
The method according to claim 5,

The step S60 is made of resistance heating by sending a current directly to the assembly,

The step S61 is made by installing a pair of electrodes at both ends of the assembly to send a current to the finishing member located at both ends of the hollow member,

The step S62 is a hollow coil spring manufacturing method characterized in that one electrode is installed at one end of the assembly, the other electrode is installed at the other end to flow a current through the assembly as a whole.
The method according to claim 5,

The step S61 consists of heating the finishing member to a temperature of less than 300 ℃ 700 ℃,

The S62 step is a hollow coil spring manufacturing method, characterized in that for heating the assembly to a temperature of less than 700 ℃ 1100 ℃.