JPH07256385A - Method for forging housing for ball joint - Google Patents
Method for forging housing for ball jointInfo
- Publication number
- JPH07256385A JPH07256385A JP6072770A JP7277094A JPH07256385A JP H07256385 A JPH07256385 A JP H07256385A JP 6072770 A JP6072770 A JP 6072770A JP 7277094 A JP7277094 A JP 7277094A JP H07256385 A JPH07256385 A JP H07256385A
- Authority
- JP
- Japan
- Prior art keywords
- housing
- forged product
- forging
- opening part
- preliminary
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C11/00—Pivots; Pivotal connections
- F16C11/04—Pivotal connections
- F16C11/06—Ball-joints; Other joints having more than one degree of angular freedom, i.e. universal joints
- F16C11/0619—Ball-joints; Other joints having more than one degree of angular freedom, i.e. universal joints the female part comprising a blind socket receiving the male part
- F16C11/0623—Construction or details of the socket member
- F16C11/0628—Construction or details of the socket member with linings
- F16C11/0633—Construction or details of the socket member with linings the linings being made of plastics
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C11/00—Pivots; Pivotal connections
- F16C11/04—Pivotal connections
- F16C11/06—Ball-joints; Other joints having more than one degree of angular freedom, i.e. universal joints
- F16C11/0685—Manufacture of ball-joints and parts thereof, e.g. assembly of ball-joints
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C2220/00—Shaping
- F16C2220/40—Shaping by deformation without removing material
- F16C2220/48—Shaping by deformation without removing material by extrusion, e.g. of metallic profiles
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Rolling Contact Bearings (AREA)
- Forging (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、例えば自動車の懸架装
置及び操舵装置等に使用されるボールジョイントのハウ
ジングの鍛造成形方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forging a housing of a ball joint used in, for example, a suspension system and a steering system of an automobile.
【０００２】[0002]
【従来の技術】自動車の懸架装置及び操舵装置等に使用
されるボールジョイントは、図２に示す如き構造であ
る。つまりボールジョイント１は、球状の球頭部４とそ
の球頭部４から突出する柄部３とからなるボールスタッ
ド２と、ボールスタッド２の球頭部４を包持する上下一
対のベアリング５，６と、ベアリング５，６を保持し、
ボールスタッド２の柄部３を一端小開口部５２から突出
させると共に他端大開口部５３内周に閉止板７を固定さ
せるハウジング５１と、ハウジング５１の小開口部５２
外周に一端圧入部１０が固定され、ボールスタッド２の
柄部３外周に他端嵌装部９が固定されるダストカバー８
からなる。2. Description of the Related Art A ball joint used in a suspension system and a steering system of an automobile has a structure as shown in FIG. That is, the ball joint 1 includes a ball stud 2 including a spherical ball head 4 and a handle portion 3 protruding from the ball head 4, and a pair of upper and lower bearings 5, which surround the ball head 4 of the ball stud 2. 6 and bearings 5 and 6,
A housing 51 in which the handle 3 of the ball stud 2 is projected from the small opening 52 at one end and the closing plate 7 is fixed to the inner circumference of the large opening 53 at the other end, and a small opening 52 of the housing 51.
A dust cover 8 having one end press-fitted portion 10 fixed to the outer periphery and the other end fitting portion 9 fixed to the outer periphery of the handle portion 3 of the ball stud 2.
Consists of.
【０００３】このようなボールジョイント１のハウジン
グ５１は従来から図４に示す如く、鍛造及び切削によっ
て成形されていた。この工程を図に基づいて説明する
と、まず図４の（イ）に示す如き円盤状の素材１２１を
前方押出し等の鍛造成形により、図４の（ロ）に示す如
き軸方向一端に底部１３３を有するカップ状の予備鍛造
品１３１に成形する。次に、予備鍛造品１３１の底部１
３３を打ち抜き、図４の（ハ）に示す如き予備開口部１
４３を設けた中間鍛造品１４１に成形する。そして最後
に切削加工にて中間鍛造品１４１の内周及び外周を仕上
げて、図４の（ニ）に示す如きハウジング１５１を成形
していた。The housing 51 of the ball joint 1 as described above has conventionally been formed by forging and cutting, as shown in FIG. This process will be described with reference to the drawings. First, a disc-shaped material 121 as shown in FIG. 4A is formed by forging such as forward extrusion to form a bottom portion 133 at one end in the axial direction as shown in FIG. 4B. The cup-shaped preliminary forged product 131 is formed. Next, the bottom 1 of the pre-forged product 131
33 is punched out, and the preliminary opening 1 as shown in FIG.
The intermediate forged product 141 provided with 43 is formed. Finally, the inner periphery and the outer periphery of the intermediate forged product 141 are finished by cutting to form the housing 151 as shown in FIG.
【０００４】[0004]
【発明が解決しようとする課題】上述の如きボールジョ
イント用ハウジングの成形方法では、切削加工にて仕上
げ加工が施されるため、ハウジング１５１の小開口部１
５２のメタルフローが切れ、強度的に若干低下するとい
う傾向がある。この点において、ボールジョイント１の
ボールスタッド２はハウジング５１の小開口部５２によ
って球頭部４の抜けが防止されるので、小開口部５２の
強度低下には機能的に問題がある。In the method of molding the ball joint housing as described above, since the finishing process is performed by cutting, the small opening 1 of the housing 151 is formed.
There is a tendency that the metal flow of 52 is cut off and the strength is slightly reduced. In this respect, since the ball head 4 of the ball stud 2 of the ball joint 1 is prevented from coming off by the small opening 52 of the housing 51, there is a functional problem in reducing the strength of the small opening 52.
【０００５】また、ハウジング１５１を切削加工で仕上
げると、加工工程が増加すると共に加工工数も増加する
ため、生産性が低下し費用が増加するという問題もあ
る。Further, if the housing 151 is finished by cutting, the number of processing steps and the number of processing steps increase, so that there is a problem that productivity is lowered and cost is increased.
【０００６】そこで本発明は上述の如き課題を解決し、
ハウジングにおける小開口部の強度が高く、生産性の低
下及び費用の増加を抑制できるボールジョイント用ハウ
ジングの鍛造成形方法を提供することを目的とする。Therefore, the present invention solves the above problems,
An object of the present invention is to provide a method for forging a housing for a ball joint, in which the small opening portion of the housing has high strength and can suppress a decrease in productivity and an increase in cost.
【０００７】[0007]
【課題を解決するための手段】本発明の構成は以下のと
おりである。The constitution of the present invention is as follows.
【０００８】円柱状の素材を鍛造成形により軸方向一端
に底部を有するカップ状の予備鍛造品に成形する第一工
程と、予備鍛造品の底部を打ち抜き予備開口部を設けた
中間鍛造品を成形する第二工程と、中間鍛造品の予備開
口部外側から所望する内周形状と同形のパンチを挿入
し、予備開口部の反対側端部に内周フランジ状の小開口
部を成形すると共に内周を鍛造仕上げとしたハウジング
を成形する第三工程とからなる。A first step of forming a cylindrical material into a cup-shaped pre-forged product having a bottom portion at one axial end by forging, and an intermediate forged product in which the bottom portion of the pre-forged product is punched and a preliminary opening is provided. The second step is to insert a punch of the same shape as the desired inner peripheral shape from the outside of the preliminary opening of the intermediate forged product, and form a small opening like an inner peripheral flange at the end on the opposite side of the preliminary opening. The third step is to form a housing with a forged finish on the circumference.
【０００９】[0009]
【実施例】以下本発明の実施例を図１乃至図３に基づい
て説明する。Embodiments of the present invention will be described below with reference to FIGS.
【００１０】図２は、連接棒１６に連結されたボールジ
ョイントを表し、２は球状の球頭部４とその球頭部４か
ら突出する柄部３とからなるボールスタッドである。ボ
ールスタッド２の球頭部４は上下一対のベアリング５，
６により包持され、円筒状のハウジング５１内部に保持
される。このハウジング５１の一端小開口部５２はボー
ルスタッド２の柄部３を突出させ、他端大開口部５３は
ボールジョイント１内部を塞ぐ閉止板７をかしめ固定さ
せる。また８は、ハウジング５１の小開口部５２外周に
一端圧入部１０を固定し、ボールスタッド２の柄部３外
周に他端嵌装部９を固定するダストカバー８である。FIG. 2 shows a ball joint connected to the connecting rod 16, and 2 is a ball stud consisting of a spherical ball head 4 and a handle 3 protruding from the ball head 4. The ball head 4 of the ball stud 2 has a pair of upper and lower bearings 5,
It is enclosed by 6 and held inside a cylindrical housing 51. A small opening 52 on one end of the housing 51 projects the handle 3 of the ball stud 2, and a large opening 53 on the other end caulks and fixes a closing plate 7 that closes the inside of the ball joint 1. Further, reference numeral 8 denotes a dust cover 8 for fixing the press-fitting portion 10 at one end to the outer periphery of the small opening 52 of the housing 51 and fixing the other end fitting portion 9 to the outer periphery of the handle portion 3 of the ball stud 2.
【００１１】上記ボールジョイント１のハウジング５１
を鍛造により成形する工程を図１に基づいて説明する。The housing 51 of the ball joint 1
The process of forming by forging will be described with reference to FIG.
【００１２】まず図１の（イ）に示す如き円盤状の素材
２１を前方押出し等の鍛造成形により、図１の（ロ）に
示す如き軸方向一端に底部３３を有するカップ状の予備
鍛造品３１に成形する。次に、予備鍛造品３１の底部３
３を打ち抜き、図１の（ハ）に示す如き予備開口部４３
を設けた中間鍛造品４１に成形する。そして最後に中間
鍛造品４１を、図１の（ニ）に示す如きハウジング５１
に成形する。このハウジング５１を成形する工程を図３
に基づいて説明する。First, a disc-shaped raw material 21 as shown in FIG. 1 (a) is subjected to forging such as forward extrusion to form a cup-shaped preliminary forged product having a bottom portion 33 at one axial end as shown in FIG. 1 (b). Mold to 31. Next, the bottom 3 of the pre-forged product 31
3 is punched out, and a preliminary opening portion 43 as shown in FIG.
The intermediate forged product 41 provided with is formed. Finally, the intermediate forged product 41 is replaced with a housing 51 as shown in FIG.
To mold. The process of molding this housing 51 is shown in FIG.
It will be described based on.
【００１３】図において、左半部は鍛造成形前、右半部
は鍛造成形後の状態を表す。In the figure, the left half shows the state before forging and the right half shows the state after forging.
【００１４】まず、ハウジング５１を成形する鍛造装置
６１を説明する。７１は上型で下端部外周にハウジング
５１内周の形状と同形の外周成形段部７３を有するパン
チ７２と、パンチ７２を支持する上ガイド７４とからな
る。また８１は下型で、パンチ７２に対向する位置に貫
通孔８３を有する成形型８２と、成形型８２の貫通孔８
３に昇降可能に挿嵌されたノックアウトパンチ８５とか
らなる。成形型８２の貫通孔８３内周にはハウジング５
１外周の形状と同形の内周成形段部８４が設けられ、こ
の内周成形段部８４とノックアウトパンチ８５の上面と
より型彫空間８９が画成される。First, a forging device 61 for molding the housing 51 will be described. Reference numeral 71 denotes an upper die, which includes a punch 72 having an outer peripheral forming stepped portion 73 having the same shape as the inner periphery of the housing 51 on the outer periphery of the lower end portion, and an upper guide 74 for supporting the punch 72. Reference numeral 81 is a lower die, which is a forming die 82 having a through hole 83 at a position facing the punch 72, and the through hole 8 of the forming die 82.
3 and a knockout punch 85 that is vertically movable. The housing 5 is provided inside the through hole 83 of the molding die 82.
1 is provided with an inner peripheral forming stepped portion 84 having the same shape as the outer peripheral shape, and a die engraving space 89 is defined by the inner peripheral forming stepped portion 84 and the upper surface of the knockout punch 85.
【００１５】上記鍛造金型６１により、中間鍛造品４１
からハウジング５１を成形する工程を説明する。An intermediate forged product 41 is produced by the forging die 61.
The process of molding the housing 51 from will be described.
【００１６】図３左半部に示す如く、下型８１の型彫空
間８９に予備開口部４３が上側に位置するように中間鍛
造品４１を配置し、上型７１を下降させる。そしてパン
チ７２を下型８１の型彫空間８９内に挿入させると共
に、中間鍛造品４１からハウジング５１への鍛造成形が
開始される。このとき中間鍛造品４１の反予備開口部に
あたる反対側端部４４は軸心側に延出され小開口部５２
が成形されると共に内周が鍛造仕上げされ、図３右半部
に示す如くハウジング５１が鍛造成形される。このよう
に成形されたハウジング５１は、その後、上型７１が上
昇し、連続的にノックアウトパンチ８５が上昇して下型
８１から取り出され成形が完了する。As shown in the left half of FIG. 3, the intermediate forged product 41 is arranged in the die engraving space 89 of the lower die 81 so that the preliminary opening 43 is located on the upper side, and the upper die 71 is lowered. Then, the punch 72 is inserted into the die engraving space 89 of the lower die 81, and the forging from the intermediate forged product 41 to the housing 51 is started. At this time, the opposite end portion 44 of the intermediate forged product 41 corresponding to the anti-preliminary opening portion is extended to the axial center side so that the small opening portion 52 is formed.
And the inner circumference is forged, and the housing 51 is forged as shown in the right half of FIG. After that, in the housing 51 thus molded, the upper die 71 rises, the knockout punch 85 continuously rises, and the housing 51 is taken out from the lower die 81 to complete the molding.
【００１７】従って、ハウジング５１は鍛造工程のみで
成形されるため、メタルフローを切ることなく成形する
ことができ、切削加工が不用となる。Therefore, since the housing 51 is formed only by the forging process, it can be formed without cutting the metal flow, and the cutting process is unnecessary.
【００１８】[0018]
【発明の効果】以上のように本発明によると、円柱状の
素材を鍛造成形により軸方向一端に底部を有するカップ
状の予備鍛造品に成形する第一工程と、予備鍛造品の底
部を打ち抜き予備開口部を設けた中間鍛造品を成形する
第二工程と、中間鍛造品の予備開口部外側から所望する
内周形状と同形のパンチを挿入し、予備開口部の反対側
端部に内周フランジ状の小開口部を成形すると共に内周
を鍛造仕上げとしたハウジングを成形する第三工程とか
らなるため、ハウジングのメタルフローを切ることなく
成形することができ、特にボールスタッドの抜け強度が
要求される小開口部においても高い強度を有する。また
切削加工無しで成形されるため、加工工程及び加工工数
を削減できるので、ハウジングの生産性が向上し更に加
工費を抑制できる。As described above, according to the present invention, the first step of forming a cylindrical raw material into a cup-shaped pre-forged product having a bottom portion at one axial end by forging, and punching out the bottom portion of the pre-forged product. The second step of forming an intermediate forged product with a preliminary opening, and inserting a punch of the same shape as the desired inner peripheral shape from the outside of the preliminary forging of the intermediate forged product, and the inner circumference at the opposite end of the preliminary opening. Since it consists of the third step of molding the flange-shaped small opening and molding the housing with the inner circumference forged, it can be molded without cutting the metal flow of the housing, especially the ball stud pull-out strength. It has high strength even in the required small openings. Further, since the molding is performed without cutting, the number of processing steps and the number of processing steps can be reduced, so that the productivity of the housing is improved and the processing cost can be further suppressed.
【図１】本発明の実施例によるボールジョイント用ハウ
ジングの鍛造成形工程を表す説明図である。FIG. 1 is an explanatory view showing a forging process of a ball joint housing according to an embodiment of the present invention.
【図２】ハウジングを使用したボールジョイントを表す
部分断面平面図である。FIG. 2 is a partial cross-sectional plan view showing a ball joint using a housing.
【図３】本発明の実施例による中間鍛造品からハウジン
グを成形する工程を表し、左半部は鍛造成形前、右半部
は鍛造成形後の状態を表す部分断面平面図である。FIG. 3 is a partial cross-sectional plan view showing a step of forming a housing from an intermediate forged product according to an embodiment of the present invention, in which the left half part shows a state before forging and the right half part shows a state after forging.
【図４】従来のボールジョイント用ハウジングの鍛造成
形工程を表す説明図である。FIG. 4 is an explanatory view showing a forging process of a conventional ball joint housing.
２１ 素 材 ３１ 予備鍛造品 ３３ 底 部 ４１ 中間鍛造品 ４３ 予備開口部 ４４ 反対側端部 ５１ ハウジング ５２ 小開口部 ７２ パンチ 21 Material 31 Preform Forging 33 Bottom 41 Intermediate Forging 43 Preliminary Opening 44 Opposite End 51 Housing 52 Small Opening 72 Punch
Claims (1)
軸方向一端に底部（３３）を有するカップ状の予備鍛造
品（３１）に成形する第一工程と、前記予備鍛造品（３
１）の底部（３３）を打ち抜き予備開口部（４３）を設
けた中間鍛造品（４１）を成形する第二工程と、前記中
間鍛造品（４１）の予備開口部（４３）外側から所望す
る内周形状と同形のパンチ（７２）を挿入し、予備開口
部（４３）の反対側端部（４４）に内周フランジ状の小
開口部（５２）を成形すると共に内周を鍛造仕上げとし
たハウジング（５１）を成形する第三工程とからなるこ
とを特徴とするボールジョイント用ハウジングの鍛造成
形方法。1. A first step of forming a cylindrical raw material (21) into a cup-shaped pre-forged product (31) having a bottom portion (33) at one axial end by forging, and the pre-forged product (3).
1) A second step of punching out the bottom portion (33) of the intermediate forged product (41) provided with a preliminary opening portion (43), and desired from the outside of the preliminary opening portion (43) of the intermediate forged product (41). A punch (72) having the same shape as the inner peripheral shape is inserted, and a small opening portion (52) having an inner peripheral flange shape is formed at the opposite end portion (44) of the preliminary opening portion (43), and the inner periphery is forged. And a third step of molding the housing (51) described above.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6072770A JPH07256385A (en) | 1994-03-17 | 1994-03-17 | Method for forging housing for ball joint |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6072770A JPH07256385A (en) | 1994-03-17 | 1994-03-17 | Method for forging housing for ball joint |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07256385A true JPH07256385A (en) | 1995-10-09 |
Family
ID=13498950
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6072770A Pending JPH07256385A (en) | 1994-03-17 | 1994-03-17 | Method for forging housing for ball joint |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07256385A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7082805B2 (en) | 2003-11-25 | 2006-08-01 | Denso Corporation | Manufacturing method for cylindrical part |
| CN103447765A (en) * | 2013-08-27 | 2013-12-18 | 贵州安大航空锻造有限责任公司 | Preparing method of G20Cr2Ni4 bearing steel large-scale special-shaped cross section annular blank |
| CN103447769A (en) * | 2013-08-27 | 2013-12-18 | 贵州安大航空锻造有限责任公司 | Preparing method of TC4 alloy large-scale special-shaped cross section annular blank |
| CN113784808B (en) * | 2019-04-23 | 2024-03-01 | 国立大学法人东海国立大学机构 | Precision forging method, precision forging device and precision forging piece |
-
1994
- 1994-03-17 JP JP6072770A patent/JPH07256385A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7082805B2 (en) | 2003-11-25 | 2006-08-01 | Denso Corporation | Manufacturing method for cylindrical part |
| DE102004056740B4 (en) * | 2003-11-25 | 2006-11-23 | Denso Corp., Kariya | Manufacturing method for a cylindrical part |
| CN100389928C (en) * | 2003-11-25 | 2008-05-28 | 株式会社电装 | Manufacturing method for cylindrical part |
| CN103447765A (en) * | 2013-08-27 | 2013-12-18 | 贵州安大航空锻造有限责任公司 | Preparing method of G20Cr2Ni4 bearing steel large-scale special-shaped cross section annular blank |
| CN103447769A (en) * | 2013-08-27 | 2013-12-18 | 贵州安大航空锻造有限责任公司 | Preparing method of TC4 alloy large-scale special-shaped cross section annular blank |
| CN113784808B (en) * | 2019-04-23 | 2024-03-01 | 国立大学法人东海国立大学机构 | Precision forging method, precision forging device and precision forging piece |
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