KR20060026133A - Pipe cold forging processing method and pipe cold forging the bicycle hub which is processed - Google Patents

Pipe cold forging processing method and pipe cold forging the bicycle hub which is processed Download PDF

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Publication number
KR20060026133A
KR20060026133A KR1020040074880A KR20040074880A KR20060026133A KR 20060026133 A KR20060026133 A KR 20060026133A KR 1020040074880 A KR1020040074880 A KR 1020040074880A KR 20040074880 A KR20040074880 A KR 20040074880A KR 20060026133 A KR20060026133 A KR 20060026133A
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South Korea
Prior art keywords
cold forging
bicycle hub
raw material
hub
gear
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KR1020040074880A
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Korean (ko)
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최복기
나완용
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주식회사 예일하이테크
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Publication of KR20060026133A publication Critical patent/KR20060026133A/en

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D53/00Making other particular articles
    • B21D53/86Making other particular articles other parts for bicycles or motorcycles
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21JFORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J3/00Lubricating during forging or pressing
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21KMAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
    • B21K1/00Making machine elements
    • B21K1/28Making machine elements wheels; discs
    • B21K1/40Making machine elements wheels; discs hubs
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21KMAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
    • B21K1/00Making machine elements
    • B21K1/56Making machine elements screw-threaded elements

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Forging (AREA)

Abstract

본 발명은 파이프 냉간단조 가공방법 및 상기 방법에 의해 얻어진 자전거용 허브에 관한 것으로,The present invention relates to a pipe cold forging processing method and a bicycle hub obtained by the method,

자전거용 허브의 제조방법은, 요철부가 형성된 외면 상단에 나사부가 형성되고 내면에는 래칫기어와 산형기어가 형성된 자전거용 허브의 제조방법에 있어서; The method for manufacturing a bicycle hub includes a method of manufacturing a bicycle hub having a screw portion formed on an upper surface of an outer surface on which an uneven portion is formed and a ratchet gear and a mountain gear on an inner surface thereof;

상기 자전거용 허브보다 큰 내,외경을 가지는 인발강관을 원소재로 하여 풀림을 실시하는 소둔공정과; 상기 소둔된 원소재의 표면을 쇼트처리한 후 원소재와 금형의 접착방지를 위해 윤활재를 피막시키는 표면처리공정과; 상기 표면처리된 원소재를 적정길이로 절단한 후 내부에 래칫기어와 산행기어를 구비하는 설계규격 및 형태가 되도록 단계적으로 축관시켜 반제품을 얻는 냉간단조 공정과; 상기 냉간단조된 반제품의 외면 상단에 나사부를 형성시켜 완제품을 얻는 후처리 공정; 으로 이루어진 것을 특징으로 하고,An annealing step of performing annealing using a drawn steel pipe having an inner diameter and an outer diameter larger than that of the bicycle hub; A surface treatment step of coating a lubricating material to prevent adhesion between the raw material and the mold after short-treating the surface of the annealed raw material; A cold forging process of cutting the surface-treated raw material to a suitable length and then condensing stepwise to have a design specification and a shape having a ratchet gear and a climbing gear inside; A post-treatment step of obtaining a finished product by forming a screw on an upper surface of the outer surface of the cold forged semi-finished product; Characterized in that consisting of,

상기 제조방법에 의해 얻어지는 본 발명 자전거용 허브는 원소재인 인발강관을 소둔공정, 쇼트 및 피막공정, 절단 및 다단계 냉간단조공정을 차례로 실시하여 그 내면에 래칫기어와 산기어을 포함하는 설계규격 및 형태의 허브를 얻고, 후처리 공정에 의해 외면 필요부위에 나사부를 형성시켜 완성된 것을 특징으로 한다.The bicycle hub of the present invention obtained by the above manufacturing method is subjected to annealing process, shot and coating process, cutting and multi-step cold forging process of the drawn steel pipe which is a raw material, in order to include a ratchet gear and an acid gear on its inner surface. It is characterized in that the hub is obtained, and a threaded portion is formed on the required portion of the outer surface by a post-treatment process.

파이프, 허브, 냉간단조Pipe, Hub, Cold Forging

Description

파이프 냉간단조 가공방법 및 파이프 냉간단조 가공된 자전거용 허브{Pipe cold forging processing method and pipe cold forging the bicycle hub which is processed}Pipe cold forging processing method and pipe cold forging the bicycle hub which is processed}

도 1은 본 발명에 의한 파이프 냉간단조 가공방법의 제조공정 블럭도1 is a manufacturing process block diagram of the cold cold forging method according to the present invention

도 2는 본 발명에 의해 파이프 냉간단조 가공된 제품의 외관사시도,Figure 2 is an external perspective view of the product cold forged pipe processed by the present invention

도 3은 도2의 파이프 냉간단조 가공된 제품에 후가공 처리를 행하여 얻어진 자전거용 허브의 절결사시도     FIG. 3 is a cutaway perspective view of a bicycle hub obtained by subjecting the pipe cold forged product of FIG. 2 to a post-processing treatment. FIG.

<도면의 주요부분에 대한 설명>    <Description of main parts of drawing>

1 : 허브 2 : 요철부    1: hub 2: uneven portion

3 : 래칫기어 4 : 산형기어    3: Ratchet Gear 4: Mountain Gear

5 : 나사부    5: screw

본 발명은 파이프 냉간단조 가공방법 및 상기 방법에 의해 얻어진 자전거용 허브, 더욱 상세히는 중공의 인발강관을 냉간단조에 의해 다단계로 축관 시키는 가공방법 및 상기 방법에 의해 얻어진 자전거용 허브에 관한 것이다.The present invention relates to a pipe cold forging processing method and a bicycle hub obtained by the above method, and more particularly, to a hollow tube with a hollow drawing steel pipe by cold forging in multiple stages, and a bicycle hub obtained by the above method.

일반적으로 자전거용 허브는 전,후륜을 축 고정시키기 위한 구성품으로, 근래에는 자전거의 주행 중 일정 압력으로 타이어에 공기를 주입할 수 있게 구성된 허브가 제시되어 있다.Generally, the hub for a bicycle is a component for fixing the front and rear wheels, and recently, a hub configured to inject air into a tire at a predetermined pressure while driving the bicycle has been proposed.

상기한 허브는 타이어에 미세한 손상이 발생되어 공기압이 누출되는 경우에도 주행력에 의해 타이어에 공기가 주입되므로 비교적 고가의 자전거, 예를 들면 산악용 자전거 또는 경기용 자전거 등에 널리 채택되고 있으며, 생산기술의 발달과 사용자의 요구에 의해 점차 그 사용이 보편화되고 있다.The above-mentioned hubs are widely used for relatively expensive bicycles, such as mountain bikes or racing bicycles, because air is injected into the tires by the driving force even when fine tire damage occurs and air pressure leaks. Its use is becoming more and more common due to the demands of users and users.

그런데, 종래의 자전거용 허브는 환봉을 열간단조에 의해 적정형태 및 규격의 소재를 얻고, 이 소재의 내부를 중공이 되도록 가공하며, 여러가지 공정을 다양한 장치에 의해 진행하여 소재의 내, 외면에 필요 구성부를 가공한 후, 표면가공을 실시하여 완제품을 얻게 되었다.By the way, the conventional bicycle hub is obtained by hot forging the round bar to obtain the material of the appropriate shape and standard, the inside of the material is processed to be hollow, and various processes are carried out by various devices to be required on the inside and outside of the material After processing the components, the surface was processed to obtain a finished product.

따라서 공수와 가공장치 및 소요시간의 증가로 인해 원가상승의 주 요인을 제공하게 되며, 사용시에는 주조물의 특성상 내충격성이 낮으므로 제품의 수명이 단축된다는 등의 문제점들이 지적되고 있다.Therefore, the main factors of the cost increase due to the increase of the man-hours, the processing equipment and the required time, and the problems such as shortening the life of the product because the impact resistance is low due to the characteristics of the casting when used.

본 발명은 상기한 문제점들을 적극적으로 해소시키기 위하여 중공의 인발강관을 냉간단조에 의해 다단계로 축관시켜 필요형태 및 규격의 완제품을 얻도록 함으로써 생산성 향상과 원가 절감을 구현함과 동시에 대량생산이 가능하도록 하고, 제품의 내충격성 향상에 의해 고장발생율 최소화와 제품신뢰도 향상을 도모할 수 있게 된 파이프 냉간단조 가공방법 및 상기 방법에 의해 얻어진 자전거용 허브를 제공함에 그 목적이 있다.In order to solve the above problems actively, the hollow drawn steel pipe is condensed in multiple stages by cold forging to obtain a finished product of the required form and specification, thereby realizing productivity and cost reduction and enabling mass production. In addition, the object of the present invention is to provide a cold forging process for pipes and a bicycle hub obtained by the above method, which can minimize the failure rate and improve the product reliability by improving the impact resistance of the product.

상기 목적을 효과적으로 달성하기 위한 본 발명 파이프 냉간단조 가공방법은,Pipe cold forging processing method of the present invention for achieving the above object effectively,

요철부가 형성된 외면 상단에 나사부가 형성되고 내면에는 래칫기어와 산형기어가 형성된 자전거용 허브를 제조함에 있어서;In manufacturing a bicycle hub having a screw portion is formed on the upper surface of the outer surface is formed irregularities and ratchet gears and mountain gears;

상기 자전거용 허브보다 큰 내,외경을 가지는 인발강관을 원소재로 하여 풀림을 실시하는 소둔공정과;An annealing step of performing annealing using a drawn steel pipe having an inner diameter and an outer diameter larger than that of the bicycle hub;

상기 소둔된 원소재의 표면을 청정처리 한 후 원소재와 금형의 접착방지를 위해 윤활재를 피막시키는 표면처리공정과;A surface treatment process of cleaning the surface of the annealed raw material and then coating a lubricant to prevent adhesion between the raw material and the mold;

상기 표면처리 된 원소재를 적정길이로 절단한 후 내부에 래칫기어와 산행기어를 구비하는 설계규격 및 형태가 되도록 단계적으로 축관시켜 반제품을 얻는 냉간단조 공정과; A cold forging process of cutting the surface-treated raw material to an appropriate length and then condensing stepwise to form a design standard and shape including a ratchet gear and a climbing gear therein;

상기 냉간단조된 반제품의 외면 상단에 나사부를 형성시켜 완제품을 얻는 후처리 공정; 으로 이루어진 것을 특징으로 한다.A post-treatment step of obtaining a finished product by forming a screw on an upper surface of the outer surface of the cold forged semi-finished product; Characterized in that consisting of.

상기 제조방법에 의해 얻어지는 본 발명 자전거용 허브는 원소재인 인발강관을 소둔공정, 청정 및 피막공정, 절단 및 다단계 냉간단조공정을 차례로 실시하여 그 내면에 래칫기어와 산기어를 포함하는 설계규격 및 형태의 허브를 얻고, 후처리 공정에 의해 외면 필요부위에 나사부를 형성시켜 완성된 것을 특징으로 한다.The bicycle hub of the present invention obtained by the above manufacturing method is subjected to an annealing process, a clean and coating process, a cutting and a multi-step cold forging process of an drawn steel pipe, which is a raw material, in order to include a ratchet gear and an acid gear on its inner surface, and It is characterized in that the hub of the form is obtained, and a threaded portion is formed on the required portion of the outer surface by a post-treatment process.

이하에서 상기 본 발명의 바람직한 실시예를 첨부도면에 의해 상세히 설명한 다.Hereinafter, preferred embodiments of the present invention will be described in detail by the accompanying drawings.

도 1은 본 발명 파이프 냉간단조 가공방법의 제조공정을 나타낸 블록도로서, 도 2에서는 본 발명 제조방법에 의해 얻어진 자전거용 허브(1)를 나타내었다.1 is a block diagram showing a manufacturing process of the pipe cold forging method of the present invention, Figure 2 shows a bicycle hub 1 obtained by the manufacturing method of the present invention.

상기 자전거용 허브(1)는 그 외면에 필요형태의 요철부(2)를 포함하는 원통형으로 형성되고, 그 내면에는 래칫기어(3)와 기어(4)가 형성되며, 외면 일측에는 나사부(5)가 형성된 구성으로 이루어진다.The bicycle hub 1 is formed in a cylindrical shape including a concave-convex portion 2 of the required shape on its outer surface, the ratchet gear 3 and the gear 4 is formed on the inner surface, the screw portion 5 on one side of the outer surface ) Is formed.

상기 자전거용 허브(1)를 얻기 위한 본 발명 파이프 냉간단조 가공방법을 공정별로 설명한다.Pipe cold forging process of the present invention for obtaining the bicycle hub (1) will be described for each step.

- 준비 단계 --Preparation Steps-

본 발명 자전거용 허브(1)의 제조에 사용되는 소재는 인발강관이 선택되며, 인발강관의 내,외경은 완성된 허브(1)의 내,외경보다 큰 규격의 소재가 선택된다.The material used in the manufacture of the bicycle hub 1 of the present invention is a pulled steel pipe is selected, the inner and outer diameter of the drawn steel pipe is selected from the material of the standard larger than the inner, outer diameter of the completed hub (1).

- 소둔공정 --Annealing Process-

선택된 인발강관의 냉간단조시 가공성을 향상시키기 위하여 실시되는 소둔공정은 간접가열식 연속소둔로에 의해 680℃ ~700℃의 온도에서 30분간 연속가열 한 후, 공냉시키게 된다.The annealing process performed to improve the workability during cold forging of the selected drawn steel pipe is continuously heated at a temperature of 680 ° C. to 700 ° C. for 30 minutes by an indirect heating continuous annealing furnace, followed by air cooling.

- 표면 처리공정 --Surface Treatment Process-

상기 소둔처리 된 인발강관의 표면에 산처리 와 수세처리를 실시하여 청정을 유지시키고, 표면 조정제와 표면 윤활제를 이용하여 표면피막을 실시하게 되는데, 이는 냉간단조 진행시에 단조압력에 의한 인발강관과 금형의 압착 또는 금형의 마모가속, 인발강관의 성형불량, 마킹 및 크랙방지를 위함이다.The surface of the annealed drawn steel pipe is subjected to acid treatment and rinsing treatment to maintain cleanness, and surface coating is performed by using a surface conditioner and a surface lubricant. This is to prevent mold pressing, mold acceleration, mold draw tube failure, marking and cracking.

상기 표면 조정제로는 인산염이 사용되며, 60℃ ~70℃ 의 온도에서3분간 침적시키게 된다.Phosphate is used as the surface modifier, and is deposited for 3 minutes at a temperature of 60 ° C to 70 ° C.

또한 상기 표면 윤활제로는 식물성유지가 사용되며, 60℃ ~70℃ 의 온도에서10분간 침적시키게 된다.In addition, the vegetable oil is used as the surface lubricant, it is deposited for 10 minutes at a temperature of 60 ℃ ~ 70 ℃.

- 냉간단조공정 --Cold Forging Process-

상기 표면처리 된 인발강관을 내,외금형에 의해 단계적으로 축관시키게 되는데, 본 발명에서는 냉간 5단 단조장치를 사용하여 단조공정을 실시하게 된다.The surface-treated drawn steel pipe is piped step by step by the inner and outer molds. In the present invention, the forging process is performed using a cold five-step forging apparatus.

이에 따라 인발강관은 설계규격의 허브(1)로 형성되는데, 그 외면에는 요철부(2)가, 내면에는 래칫기어(3)와 산형기어(4)가 단조과정에서 형성된다.Accordingly, the drawn steel pipe is formed as a hub (1) of the design standard, the uneven portion (2) on the outer surface, the ratchet gear (3) and the mountain gear (4) is formed in the forging process on the inner surface.

여기에서, 상기 냉간단조장치는 허브(1)의 규격, 형태 또는 단조방법에 따라 냉간4단 단조장치 또는 냉간 6단 단조장치 등으로 변형 실시될 수 있음은 물론이다.Here, of course, the cold forging device may be modified into a cold four-step forging device or a cold six-step forging device according to the standard, form or forging method of the hub (1).

- 후처리 공정 -Post-treatment process

상기 단조공정에 의해 얻어진 반제품 허브(1)의 외면에 나사부(5)를 형성시키는 가공에 의해 완성된 자전거용 허브(1)를 얻게 된다.The bicycle hub 1 which is completed by the process of forming the screw part 5 in the outer surface of the semi-finished hub 1 obtained by the said forging process is obtained.

이상의 설명에서와 같이 본 발명은 중공의 인발강관을 냉간단조에 의해 다단계로 축관시켜 필요형태 및 규격의 완제품을 얻도록 함으로써 생산성 향상과 원가 절감을 구현함과 동시에 대량생산이 가능하도록 하고, 제품의 내충격성 향상에 의해 고장발생율 최소화와 제품신뢰도 향상을 도모할 수 있는 등의 광범위한 효과가 있다. As described above, the present invention allows the hollow drawn steel pipe to be condensed in multiple stages by cold forging to obtain a finished product of a required form and specification, thereby realizing productivity and cost reduction and enabling mass production. Improving impact resistance has a wide range of effects, such as minimizing failure rate and improving product reliability.

Claims (2)

요철부가 형성된 외면 상단에 나사부가 형성되고 내면에는 래칫기어와 산형기어가 형성된 자전거용 허브를 제조함에 있어서;In manufacturing a bicycle hub having a screw portion is formed on the upper surface of the outer surface is formed irregularities and ratchet gears and mountain gears; 상기 자전거용 허브보다 큰 내,외경을 가지는 인발강관을 원소재로 하여 풀림을 실시하는 소둔공정과;An annealing step of performing annealing using a drawn steel pipe having an inner diameter and an outer diameter larger than that of the bicycle hub; 상기 소둔된 원소재의 표면을 쇼트처리한 후 원소재와 금형의 접착방지를 위해 윤활재를 피막시키는 표면처리공정과;A surface treatment step of coating a lubricating material to prevent adhesion between the raw material and the mold after short-treating the surface of the annealed raw material; 상기 표면처리된 원소재를 적정길이로 절단한 후 내부에 래칫기어와 산행기어를 구비하는 설계규격 및 형태가 되도록 단계적으로 축관시켜 반제품을 얻는 냉간단조 공정과; A cold forging process of cutting the surface-treated raw material to a suitable length and then condensing stepwise to have a design specification and a shape having a ratchet gear and a climbing gear inside; 상기 냉간단조된 반제품의 외면 상단에 나사부를 형성시켜 완제품을 얻는 후처리 공정; 으로 이루어진 것을 특징으로 하는 파이프 냉간단조 가공방법.A post-treatment step of obtaining a finished product by forming a screw on an upper surface of the outer surface of the cold forged semi-finished product; Pipe cold forging processing method characterized in that consisting of. 원소재인 인발강관을 소둔공정, 표면청정 및 피막공정, 절단 및 다단계 냉간단조공정을 차례로 실시하여 그 내면에 래칫기어와 산형기어를 포함하는 설계규격 및 형태의 허브를 얻고, 후처리 공정에 의해 외면 필요부위에 나사부를 형성시켜 완성된 것을 특징으로 하는 파이프 냉간단조 가공된 자전거용 허브.The raw material drawn steel pipe is subjected to annealing process, surface cleaning and coating process, cutting and multi-step cold forging process, and the design standard and shape hub including ratchet gear and ridge gear is obtained on the inner surface, and by post-treatment process Pipe cold forged bicycle hub, characterized in that the completed by forming a threaded portion on the outer surface.
KR1020040074880A 2004-09-18 2004-09-18 Pipe cold forging processing method and pipe cold forging the bicycle hub which is processed KR20060026133A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101503885B1 (en) * 2013-11-19 2015-03-19 (주)영완 Method for manufacturing a hinge axile bolt for folding bycycle
WO2020004681A1 (en) * 2018-06-26 2020-01-02 (주)한국정공 Method for manufacturing pulley for vehicle compressor

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101503885B1 (en) * 2013-11-19 2015-03-19 (주)영완 Method for manufacturing a hinge axile bolt for folding bycycle
WO2020004681A1 (en) * 2018-06-26 2020-01-02 (주)한국정공 Method for manufacturing pulley for vehicle compressor

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