KR102344702B1 - Inner tube manufacturing process that is mounted on the suspension for passenger cars - Google Patents

Abstract

The present invention relates to a manufacturing method of an inner tube to be mounted on a suspension for a passenger car, which comprises the following steps of: performing piercing on a main piercing hole formed at one side of the inner tube from an inner side to an outer side of the inner tube by a cam piercing method such that the main piercing hole is joined into a branched porthole of a middle tube constituting a shock absorber, or a suspension for a passenger car; compressing a part of the main piercing hole formed on the inner tube from the outside of the inner tube through a compression boring to correct roundness; performing piercing by a cam piercing method to form a plurality of sub piercing holes on the other side of the inner tube such that they face the main piercing hole; making deburring which removes burrs on the sub piercing hole and forming a slow slope on chamfered portion of the sub piercing hole by a counter sink blade having a predetermined angle; and removing remaining chips generated by piercing and deburring on the sub piercing hole. Accordingly, precision of the piercing hole formed on the inner tube can be enhanced.

Description

Inner tube manufacturing process that is mounted on the suspension for passenger cars}

The present invention relates to a manufacturing process of an inner tube mounted on a shock absorber, which is a suspension for a passenger car, and more specifically, installed to enable longitudinal driving of a piston rod constituting a variable fast absorber in charge of a suspension function for a passenger car The present invention relates to a method for manufacturing a suspension inner tube capable of forming an inner tube by performing compression processing and a deburring process on the piercing hole in order to improve the precision of the piercing hole in the piercing forming process of the inner tube.

In general, a shock absorber installed in a vehicle improves riding comfort by absorbing and buffering vibrations or shocks received from a road surface during driving. The shock-up absorber is composed of a piston rod installed inside the cylinder to enable compression and tension stroke, and a piston valve coupled to the piston rod and positioned inside the cylinder to generate a damping force.

A damping force variable shock absorber that can set different damping force characteristics according to the purpose of use of the vehicle is being applied to a vehicle. The damping force variable shock absorber is installed inside the outer tube, the outer tube, and the piston rod is installed to be movable in the longitudinal direction. A middle tube that functions as a separator tube is included.

The inner tube is a core component mounted inside the electronically controlled suspension, and oil must flow through a reservoir chamber that forms a flow path formed between an inner tube and a middle tube. At this time, it is one of the key parts that is connected to the solenoid valve to form a flow path.

As the application of electronically controlled damping technology with fast response characteristics increases to improve vehicle performance, the application of high-performance solenoid valves and the importance of inner tubes with high dimensional precision and mechanical durability are increasing.

(Korea Patent No. 10-1761868, July 26, 2017) (Korea Patent Publication No. 10-2021-0048360, May 3, 2021)

In order to improve the precision of the piercing hole formed on the inner tube when forming the inner tube mounted on the shock-up absorber, which is a suspension for a passenger car, the present invention performs compression processing and deburring process on the piercing hole to form the inner tube. An object of the present invention is to provide a method for manufacturing an inner tube constituting a suspension.

In the manufacturing process of the inner tube mounted on the suspension for a passenger car according to the present invention for achieving the above object, the main formed on one side of the inner tube to be coupled to the branch porthole of the middle tube constituting the shock absorber, which is the suspension for the passenger car. piercing the piercing hole from the inside to the outside of the inner tube in a cam piercing manner; correcting roundness by compressing the main piercing hole formed in the inner tube from the outside of the inner tube through compression boring; piercing a plurality of sub-piercing holes on the other side of the inner tube to face the main piercing holes in a cam-piercing manner; Deburring step of removing the burr for the sub-piercing hole and forming a gentle slope on the chamfer of the sub-piercing hole through a countersink blade having a specific angle; and removing the remaining chips generated by the piercing and deburring of the sub-piercing hole; characterized in that it proceeds sequentially.

In the above, piercing from the inside to the outside of the inner tube is piercing from the inside to the outside in a cam piercing manner using the main piercing unit 20, and the main piercing unit 20 is the first upper mold (210), a push pin mold 220 coupled to the upper mold in a wedge manner, an inner tube fixed shaft 240 disposed on one side of the push pin mold 220 to which the inner tube 1 is coupled, and the inner tube It includes a main piercing punch 230 that moves according to the movement of the push pin mold 220 within the fixed shaft 240 , and the right side of the push pin mold 220 wedged on the first upper mold 210 . Piercing is performed through a process in which the main piercing punch 230 disposed inside the inner tube 1 advances to the outside of the inner tube 1 through the direction movement.

In the manufacturing process of the inner tube mounted on the suspension for a passenger vehicle according to the present invention as described above, when the inner tube mounted on the shock-up absorber, which is a suspension for a passenger vehicle, is molded, compression processing and deburring processes for the piercing hole are performed on the inner tube. Improves the precision of the piercing hole to be formed.

1 is a conceptual diagram of a method for manufacturing a suspension inner tube according to an embodiment of the present invention.
2 is a flowchart of a manufacturing method of a method of manufacturing a suspension inner tube according to an embodiment of the present invention.
3 shows a system for manufacturing a suspension inner tube according to an embodiment of the present invention.
Figure 4 shows a device for piercing Φ19 corresponding to the main piercing hole from the inside to the outside in a cam piercing method.
5 shows a Φ19 roundness correction device.
6 shows a device for piercing the Φ7 piercing hole by 2 holes on both sides of the cam.
7 shows a coupling configuration between the mill pin and the sub-piercing punch constituting the sub-piercing unit.
8 shows a device for forming a gentle slope on a chamfer through a burr removal and a 120˚ countersink blade for the Φ7 piercing hole.
Figure 9 shows a processing apparatus for removing the remaining chips generated by the piercing and deburring of Figure 8.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and the scope of the invention to those of ordinary skill in the art It is provided for complete information. In the drawings, like reference numerals refer to like elements.

Hereinafter, a manufacturing process of an inner tube mounted on a shock absorber, which is a suspension for a passenger car, according to an embodiment of the present invention will be described with reference to FIGS. 1 to 2 .

In the process of manufacturing the inner tube, raw material warehousing, raw material cutting, both ends chamfering through CNC machining, end forming through an automated line, EPC inspection, and packaging/shipping are carried out.

Referring to the drawings, the end forming process on the suspension inner tube manufacturing system according to the embodiment of the present invention may be formed according to the following sequence.

The end forming process consists of pipe input for inner tube product molding, product waiting, full-length selection (all), vision inspection (alignment), product waiting (defective discharge), Φ19 hole piercing corresponding to the main piercing hole, piercing part of the main piercing hole The deburring process through compression, the piercing of the Φ7 hole corresponding to the sub-piercing hole, the deburring process for the piercing part of the sub-piercing hole, and the air, inner diameter air and brush process for the sub-piercing hole are followed.

The present invention pierces the main piercing hole of the inner tube that is inserted and installed along the middle tube from the inside to the outside in a cam piercing method, correcting the roundness by pressing the main piercing hole part again, the inner tube On the other side opposite to the main piercing hole placed on one side of the piercing, pierce the sub piercing hole with a cam piercing method on both sides by 2 holes. It is characterized in that it forms a gentle slope on the chamfer through the sink blade and sequentially performs processing to remove the remaining chips generated by piercing and deburring.

3 shows a system for manufacturing a suspension inner tube according to an embodiment of the present invention. In the direction from the right to the left in FIG. 3, the inner tube manufacturing system is a pipe supply unit 10, a main piercing unit 20, a first deburring unit 30, a sub-piercing unit 40, a second deburring unit 50, It includes an air brush unit 60 and a pipe discharge unit 70 .

The pipe supplied for inner tube product molding follows the Φ34.6*1.3T standard.

The product input process through the pipe supply unit 10 is to execute the cutting/CNC product through the automated equipment input process, and it is made possible through length adjustment when changing the overall length of the product. The product input process as a whole includes pipe input, product waiting, electric field selection (all numbers), vision inspection (alignment), and product waiting (defective discharge).

4 shows the main piercing unit 20 that performs Φ19 piercing corresponding to the main piercing hole from the inside to the outside in a cam piercing method with respect to the supplied inner tube forming pipe.

The main piercing part 20 is disposed on one side of the first upper mold 210, the push pin mold 220 wedged on the upper mold, and the push pin mold 220 so that the inner tube 1 is coupled. and a main piercing punch 230 that moves according to the motion of the push pin mold 220 within the inner tube fixing shaft 240 to be used. The main piercing punch 230 disposed inside the inner tube 1 through the rightward movement of the push pin mold 220 coupled in a wedge manner on the first upper mold 210 moves to the outside of the inner tube. Piercing through the process.

The first upper mold 210 is lowered, and the main piercing punch 230 disposed on the inner side of the inner tube 1 through the rightward movement of the mill pin mold 220 coupled in a wedge manner on the upper mold is the inner Piercing is performed through the process of advancing to the outside of the tube.

That is, the push pin mold 220 includes a push pin body 221 wedge-coupled on the lower end of the first upper mold 210 and a push pin separably coupled through a push pin fixing means 223 on the right side of the push pin body. 225, the lower end of the push pin has a stepped structure. The lower end of the push pin has a stepped structure in an upward direction.

In a state coupled to the inner tube fixing shaft 240, the inner tube 1 is moved to the right of the push pin 220 and the main piercing punch 230 through the stepped lower end of the push pin is pressed in the downward direction. , the lower end of the main piercing punch 220 performs piercing for the inner tube 1 coupled to the inner tube fixing shaft 240 . That is, the inner tube through the piercing blade 232 formed at the lower end of the main piercing punch by continuously performing pressurization to the main piercing punch 230 through the stepped lower end 227 of the mil pin and the lower movement of the main piercing punch. A piercing hole of Φ19 is machined on the top.

In the present invention, Φ19 piercing is performed in one place on one side of the supplied inner tube by using a 5TON hydraulic press. While satisfying the L2 hole distance to ??0.1mm, keep the roundness of the Φ19 hole below 0.1.

5 shows a front view and a side view of the first deburring unit 30, which is a roundness correction device for Φ19 main piercing hole.

The burr formed on the main piercing hole of the inner tube is compressed and removed through piercing through the process of lowering the compression boring on the upper outer side of the inner tube 1 pierced through the first deburring unit 30 . That is, the burr generated during the formation of the Φ19 main piercing hole is compressed using compression boring to remove the burr formed on the inner/outer diameter of the main piercing hole after pressing, and at the same time, the roundness of the Φ19 main piercing hole is maintained below 0.1. do.

6 shows the sub-piercing unit 40, which is a device for cam-piercing Φ7 sub-piercing holes on both sides by 2 holes for the supplied inner tube forming pipe.

The sub-piercing part 40 is disposed on one side of the second upper mold 410, the push pins 420 wedged on the second upper mold 410, and the push pins 420 to form an inner tube ( 1) includes an inner tube fixed shaft 440 to which is coupled, and a sub-piercing punch 430 that moves according to the motion of the push pin mold 220 within the inner tube fixed shaft 440 .

The second upper mold 410 is lowered, and the sub-piercing punch 430 disposed on the inside of the inner tube through the rightward movement of the push pin 420 wedged on the second upper mold 410 is performed. Piercing is performed through the process of advancing to the outside of the inner tube.

As a whole, the push pin 420 has a cylindrical long bar structure, and the left end 421 of the push pin has an inclined cross-section coupled in a wedge manner on the lower end of the second upper mold 410 while the push pin The right side of the sub-piercing punch 430 is coupled in contact with the inner side. A pair of protrusions 423 are formed on the right side of the push pin 420 to face each other in a parallel state. The pair of protrusions 423 has a shape that gradually becomes narrower toward the end.

The sub-piercing punch 430 has a structure of a lower punch 431 having a cross-section inclined to directly contact the protrusion 423 formed on the right side of the push pin 420 and a cutting blade 433 coupled to the upper portion of the lower portion of the punch.

In a state in which the inner tube 1 is coupled to the inner tube fixing shaft 440, the sub-piercing punch 430 is pressed through a pair of protrusions 423 formed on the right side of the push pin 420 in the outward direction. , The cutting blade 433 constituting the sub-piercing punch performs piercing in both directions on the inner tube 1 coupled to the inner tube fixing shaft 440 .

In the present invention, Φ7 piercing is performed in four places on the other side of the supplied inner tube using a 3TON hydraulic press. While satisfying the L1 hole distance to ??0.3mm, the Φ7 hole spacing is maintained at 90.

In the present invention, the sub-piercing hole of Ⅸ7 and the main piercing hole of Ⅸ19 should be in a straight line. A 90 degree rotation method can be applied. That is, one of the Ⅸ19 main piercing hole and Ⅸ7 sub piercing hole must be in a straight line for regulation.

Figure 8 is a device for forming a gentle slope on the chamfer of the sub-piercing hole through the removal of burrs for the Φ7 sub-piercing hole and the 120˚ three-edged countersink blade 510, the second deburring part 50. see. The distance between the deburring parts is maintained at 8.9 (+0.6mm).

9 shows the air brush unit 60 made possible through the air brushing process, and shows a processing device for brush removal of residual chips generated by piercing and deburring.

In general, by deburring and compressing the main piercing hole portion formed on the inner tube through the main piercing unit 20 of FIG. 4 again through the first deburring unit 30 of FIG. 5 to correct the roundness,

After constraining the inner diameter of the inner tube with the inner tube fixing shaft 240, which is the inner diameter core constituting the main piercing part 20 of FIG. 4, punching is performed from the inside of the inner tube to the outside using a piercing pin with a hydraulic press. After piercing the ㅨ19 hole, the outer burr generated in the main piercing hole is removed and the distorted roundness is corrected through the first deburring unit 30.

Piercing the sub-piercing holes formed by punching from the inside to the outside of the inner tube through the sub-piercing unit 40 of FIG. 6 in a cam-piercing method on both sides by 2 holes is to improve productivity, and 1 Hole If you do it step by step, you have to work 4 times, but if you do it 2 holes at a time, there is an advantage that it will be finished in two work.

Through the sub-piercing unit 40 of FIG. 6, the alignment device moves forward to check if the hole center is correct before deburring ㅨ7, and then deburring through the countersink advance through the second deburring unit 50 of FIG. After performing, rotate 90˚ and repeat as before.

After processing to remove the remaining chips generated by the piercing of FIG. 6 and the deburring of FIG. 8, air is operated to remove the remaining chips.

The above description is merely illustrative of the technical spirit of the present invention, and various modifications and variations will be possible without departing from the essential characteristics of the present invention by those skilled in the art to which the present invention pertains. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

Claims (5)

piercing a main piercing hole formed on one side of the inner tube to be coupled to a branch port hole of a middle tube constituting a shock-up absorber, which is a suspension for a passenger car, in a cam piercing manner from the inside of the inner tube to the outside;
correcting the roundness by compressing the main piercing hole formed in the inner tube from the outside of the inner tube through compression boring;
piercing the plurality of sub-piercing holes in a cam-piercing manner so as to face the main piercing holes on the other side of the inner tube;
A deburring step of removing the burr for the sub-piercing hole and forming a gentle slope on the chamfer of the sub-piercing hole through a countersink blade having a specific angle; and
Method of manufacturing a suspension inner tube, characterized in that sequentially; removing the remaining chips generated by the piercing and deburring of the sub-piercing hole.
The method of claim 1,
The piercing from the inside to the outside of the inner tube proceeds from the inside to the outside in a cam piercing method using the main piercing unit 20,
The main piercing part 20 is disposed on one side of the first upper mold 210, the push pin mold 220 wedged on the upper mold, and the push pin mold 220 so that the inner tube 1 is and a main piercing punch 230 that moves according to the motion of the push pin mold 220 within the inner tube fixed shaft 240 to be coupled and the inner tube fixed shaft 240, and is on the first upper mold 210 . Suspension for piercing through a process in which the main piercing punch 230 disposed on the inside of the inner tube 1 advances to the outside of the inner tube 1 through the rightward movement of the mill pin mold 220 coupled in a wedge manner to the A method for manufacturing an inner tube.
The method of claim 1,
The piercing of the plurality of sub-piercing holes in a cam-piercing manner is formed using the sub-piercing unit 40,
The sub-piercing part 40 is disposed on one side of the second upper mold 410 , the push pin 420 wedged on the second upper mold 410 , and the push pin 420 , and is an inner tube (1) includes an inner tube fixed shaft 440 to which is coupled, and a sub-piercing punch 430 that moves according to the motion of the push pin mold 220 within the inner tube fixed shaft 440, and a second upper mold ( 410) and the sub-piercing punch 430 disposed inside the inner tube through the rightward movement of the push pin 420 wedged on the second upper mold 410 is moved to the outside of the inner tube. A method of manufacturing a suspension inner tube that performs piercing through the process of advancing.
4. The method of claim 3,
The sub-piercing punch 430 has a punch lower portion 431 having an inclined cross section so as to directly contact the protrusion 423 formed on the right side of the push pin 420 and a cutting blade 433 coupled to the upper portion of the punch lower portion. A method for manufacturing a suspension inner tube with
delete

Images