KR20210011691A - Ball Joint with Ball Drop Prevention Structure and Manufacturing Method - Google Patents

Abstract

The present invention relates to a ball joint provided with a ball drop prevention part and a manufacturing method thereof, which may achieve the effect of simplifying the process by applying a ball drop prevention structure within an injection process rather than an external process in applying the ball drop prevention structure of the injection-type ball joint. According to the present invention, the ball joint provided with a ball drop prevention part comprises: a socket including a first opening, a second opening formed with the ball drop prevention part, and a ball receiving part; a ball stud installed in the socket; and a ball seat.

Description

Ball Joint with Ball Drop Prevention Structure and Manufacturing Method}

The present invention relates to a ball joint and a manufacturing method thereof. In particular, it relates to a vehicle ball joint and a manufacturing method thereof.

In general, a vehicle suspension device is a device that connects the vehicle body and the wheel, a spring that absorbs vibration or shock transmitted from the road surface to the vehicle body, a shock absorber that controls the operation of the spring, and a suspension arm or link that controls the operation of the wheel. Etc.

A ball joint or a ball joint is used to connect the suspension arm or link of the above-described suspension device to allow relative movement with respect to the vehicle body or wheel.

The conventional ball joint is a structure made to rotate freely by inserting the ball of a ball stud into a housing, and a ball and ball stud made of a rigid body, a housing or socket surrounding the ball stud, and interposed between the balls of the housing and the ball stud. It is composed of a cap that makes movement freely and a dust cover that prevents foreign matter from entering the interior of the housing.

The conventional ball joint as described above is typically manufactured through a series of processes as follows. That is, the socket is seated on the first mold of the mold, the cap is mounted on the ball, and the ball stud is assembled to the first mold to penetrate through the opening of the socket, and the second mold and the first mold are mold-closed. Inject the injection melt into the mold to inject the ball seat, open the mold and assemble the dust cover on the ball stud.

The opening of the socket is closed by injection molding of the ball seat. However, the ball seat alone has a weak holding force, so that the ball flows inside the socket, and the opening closing portion of the ball seat is damaged.

It is an object of the present invention to provide a ball joint and a method of manufacturing the same, which prevents the ball of the ball joint from slipping out in the axial direction by providing a ball drop prevention part in a socket.

A method of manufacturing a ball joint provided with a ball drop prevention unit according to the present invention will be described.

First, a socket having a plastic deformation portion protruding from the first opening and the second opening formed opposite the first opening is provided.

A ball stud having a ball portion and a stud portion is provided. According to an embodiment, the ball stud may include a cap and a rotation preventing blade surrounding the aspherical surface of the ball part.

The ball stud is placed in the first mold and the socket is placed in the first mold.

The first mold includes a socket receiving portion and a ball stud receiving portion. The socket accommodating portion is formed with an accommodating space for accommodating the socket.

Ball stud receiving part It is formed through the center of the socket receiving part so that the stud part of the ball stud is inserted.

As the second mold is molded and closed, the plastic deformation portion of the socket is plastically processed so that the plastic deformation portion of the socket is plastically deformed while being closed. In addition, the rotation preventing part may be formed by plastic processing at the distal end of the ball dropping prevention part.

According to an embodiment, a wrinkle-preventing structure may be formed at the distal end of the ball drop-out prevention part.

The second mold includes a second mold body, a plastic processing core, an injection melt injection unit, a sliding core, and an elastic member.

The second mold main body is molded with the first mold and includes a core receiving portion.

The plastic processing core is installed to be movable up and down in the second mold body, and an injection cavity space is formed at the top of the gate receiving part and the lower part of the gate receiving part, and the ball dropping prevention part or rotation preventing part is plastically deformed in the injection cavity space. A plastic working portion to be formed is formed. And, a first inclined surface is provided on the upper part.

It is installed in the gate receiving space of the injection melt injection part.

The sliding core includes a second inclined surface that interacts while being in contact with the first inclined surface so that the plastic processing core is moved from the first height to the second height, and is moved left and right.

The elastic member is installed in the second mold body to elastically support the movement of the plastic processing core.

The plastic deformation portion is formed in a cylindrical shape before the plastic working step, and plastically deformed after the plastic working step, so that the end portion is closed in the radial direction of the socket to form a ball drop prevention portion.

In the plastic deformation portion, the length of the closed end portion may be formed to be larger than the thickness of the ball sheet covered over the ball drop prevention portion.

The ball seat is injection-molded while the injection melt is injected into the socket and the melt is inserted into the ball drop prevention part.

Prior to injection molding the ball seat, a lubrication sheet may be installed to surround at least a portion of the ball portion of the ball stud.

The ball joint of at least one embodiment according to the present invention comprises a socket, a ball stud and a ball seat.

The socket includes a first opening and a second opening formed with a ball-off prevention portion formed by being plastically deformed and constricted at a distal end of the plastic processing portion protruding opposite the first opening, and a ball receiving portion having an accommodation space for accommodating the balls. Equipped.

The ball stud has a ball portion and a stud portion.

The ball seat is formed by injecting an injection-molded product into the socket while the ball stud is installed in the socket, so that an injection-molded product is introduced into the ball drop-out prevention part or the rotation prevention part, and surrounds the ball part.

According to at least one embodiment of the present invention, it is possible to prevent the ball from falling out, thereby obtaining a ball joint having improved durability.

In addition, according to the manufacturing method of at least one embodiment according to the present invention, the opening in which the ball is inserted in the socket is plasticized together in the process of mold closing the mold for injection molding of the ball sheet, thereby providing a ball drop prevention part The effect of simplifying the entire process can be achieved.

1 is a view showing a state in which a socket and a ball stud are installed in a second mold in an apparatus for manufacturing a ball joint having a ball drop prevention unit according to an embodiment of the present invention.
FIG. 2 is a view showing a state in which a plastic processing core is moved downward by a sliding core in a ball joint manufacturing apparatus having a ball drop prevention part according to an embodiment of the present invention.
3 is a view showing a plastic deformation portion of the socket plastically processed while the second mold is molded and closed with the first mold in the ball joint manufacturing apparatus having the ball drop-off prevention unit according to an embodiment of the present invention.
4 is a view showing a state in which an injection cavity space is formed by moving the plastic processing core upward while the sliding core is retracted in the ball joint manufacturing apparatus having a ball drop prevention unit according to an embodiment of the present invention.
5 is a view showing a state in which a ball seat is formed while an injection melt is injected in a ball joint manufacturing apparatus having a ball drop prevention part according to an embodiment of the present invention.
6 is a view showing a cap of a ball joint having a ball-off prevention unit according to an embodiment of the present invention.
FIG. 7 is a view showing a socket before plastic processing and a socket having a ball falling prevention unit and a rotation prevention unit after plastic processing in a ball joint having a ball falling prevention unit according to an embodiment of the present invention.
8 is a view showing a cross section of a socket and a ball seat in a ball joint having a ball drop-out prevention unit according to an embodiment of the present invention.
9 is a view showing a cross-section in which a ball seat is formed and a cross-section without a ball seat in a ball joint having a ball drop prevention unit according to an embodiment of the present invention.
10 is a view showing a lower portion and a cross section of a plastic processing core in a ball joint manufacturing apparatus having a ball drop-out prevention unit according to an embodiment of the present invention.
11 is a view showing a cut-out portion formed in a plastic deformation portion of a socket in a ball joint having a ball drop prevention portion according to another embodiment of the present invention.

Hereinafter, a method of manufacturing a ball joint having a ball drop prevention part according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

In the method of manufacturing a ball joint according to the present invention, first, a socket provided with a plastic deformation portion 310 protruding in the axial direction in the first opening 131 and the second opening 132 formed on the opposite side of the first opening 131 ( 130). In addition, ball studs 100 and 110 including the ball portion 100 and the stud portion 110 are provided.

When the socket 130 and the ball studs 100 and 110 are provided, the ball studs 100 and 110 and the socket 130 are positioned in the first mold as shown in FIG. 1.

Since the diameter of the first opening 131 is smaller than the diameter of the bowl part 100, the ball is not inserted into the first opening 131. Therefore, the socket 130 is installed in the first mold 140 so that the second opening 132 faces upward, and then the ball studs 100 and 110 are removed with the stud 110 facing downward. 2 It is inserted into the opening 132 and installed in the first mold 140.

In the first mold 140, an inner core accommodating portion 120 in which the socket accommodating portion 150 and the inner core 115 are accommodated is formed. The inner core receiving portion 120 is formed with a ball stud receiving portion 160. A tip portion 320 supporting the ball portion 100 is formed on the inner core 115. The tip part 320 serves to block the injection melt injection part 210 from being clouded toward the ball stud receiving part 160.

The ball stud receiving portion 160 accommodates the stud portion 110, the ball portion 100 is seated on the tip portion 320, the socket 130 is installed to surround the ball portion 100, and the plastic deformation portion 310 is It is installed facing the top.

The ball stud receiving portion 160 is formed through the center of the socket receiving portion 150 so that the stud portion 110 is inserted.

When the ball studs 100 and 110 and the socket 130 are installed in the first mold 140, as shown in FIG. 2, the sliding core 200 included in the second mold 170 is moved while the plastic processing core ( 190) is moved from the first height (h1) to the second height (h2) to prepare for plastic processing.

The second mold 170 includes a second mold body 180, a plastic processing core 190, an injection melt injection unit 210, a sliding core 200, and an elastic member.

The second mold body 180 is molded with the first mold 140 and includes a core receiving portion 185. The first mold 170 may be moved by hydraulic pressure or pneumatic pressure. Depending on the embodiment, the first mold is fixed, and the second mold 140 may be moved in the direction of the first mold 170 to be closed.

The plastic processing core 190 is installed to be movable up and down in the second mold body 180, as shown in (a) and (b) of FIG. 10, and the gate receiving part 330 and the gate receiving part at the top An injection cavity space 230 is formed under the 330, and in the injection cavity space 230, a plastic processing part 195 formed by plastically deforming the ball dropping prevention part 290 and the rotation preventing part 280 is provided. Is formed. The plastic processing core 190 is provided with a first inclined surface 191 at the top.

The plastic processing unit 195 is formed with a bent portion 196 formed in a curved surface to form a ball drop prevention portion 290 and a punching portion 197 protruding to form the rotation preventing portion 280.

The second mold 170 includes an injection melt injection part 210 and the injection melt injection part 210 is installed in the gate receiving part 330 formed in the plastic processing core 190.

Sliding core 200 is a second plastic processing core 190 is in contact with the first inclined surface 191 and interacts to move from the first height (h1) to the second height (h2) as shown in FIG. It includes an inclined surface 201 and is moved left and right.

The sliding core 200 moves in the direction of the injection melt injection unit 210 so that the plastic processing core 190 moves to a second height h2 within the second mold body 180 for a plastic deformation process, and plastic deformation is performed. Upon completion, when the sliding core 200 is moved in the opposite direction from the injection-melt injection unit 210 direction to provide a space in which the ball seat 240 is injected, the plastic processing core 190 is again at a second height h1 It moves to the first height h1. During the above process, the second mold body 180 is mold-closed with the first mold 140.

An elastic member is installed between the plastic processing core 190 and the second mold body 180, and when the sliding core 200 is moved in the opposite direction to the injection melt injection unit 210, the plastic processing core 190 becomes the second It provides elasticity to move from the height h2 to the first height h1. The elastic member may be a coil spring 220, but according to an embodiment, the plastic processing core 190 may be moved by hydraulic or pneumatic pressure instead of the coil spring.

When the plastic processing core 190 is moved from the first height h1 to the second height h2 by the sliding core 200, the second mold is mold-closed as shown in FIG. 3, so that the socket 130 The end portion 300 side of the plastic deformation portion 310 formed on the opposite side of the inlet portion of the plastic deformation portion 310 is pressed so that the rotation preventing portion 280 is plastically deformed.

In this embodiment, the rotation preventing part 280 is plastically deformed through a press, but the rotation preventing part 280 may be formed through a plastic deformation roller.

For plastic processing of the plastic deformation part 310, the second mold 170 is rapidly moved in the direction of the first mold 140 to plastically process the plastic deformation part 310. The rotation preventing part 280 may be in the shape of a groove as in this embodiment, and may be in the shape of a through hole. The shape of the rotation preventing part 280 may be at least one shape such as a circle, a polygon, and a star shape.

When plastic processing of the plastic deformation part 310 is completed, as shown in FIG. 4, the plastic processing core 190 is at a first height h1 in a state in which the second mold 170 and the first mold 140 are closed. As it moves to, the injection cavity space 230 is formed, and the injection melt injection unit 210 injects the injection melt as shown in FIG. 5. The injection melt flows into the injection cavity space 230, the socket 130, and the rotation prevention part 280, and the ball seat 240 is injection-molded.

According to the embodiment, before injection molding the ball sheet 240 by injecting an injection melt, a lubricating sheet surrounding a part of the ball part 100 may be installed on the ball part 100. The lubricating sheet may be installed before the second mold 170 is mold-closed or before the ball studs 100 and 110 are installed in the first mold 140.

The lubricating sheet may be formed integrally with the cap 250 as shown in FIG. 6 and may be configured as a separate piece. Wing portions 270 are formed on the outer surface of the lubricating sheet. The wing portion 270 is in contact with the inner surface of the socket 130 and the position of the lubrication sheet 260 is changed when the injection melt is injected, or the lubrication sheet by the flow of the ball portion 100 after the ball sheet 240 is solidified. Serves to prevent the ball seat 240 from being rotated in the circumferential direction.

The plastic deformation part 310 is formed in a cylindrical shape before the plastic processing step as shown in (a) of FIG. 7, and after the plastic processing step, it is plastically deformed as shown in (b) of FIG. The ball is closed and a ball drop prevention part 290 is formed. The rotation preventing part 280 is formed at the distal end 300 of the plastic deformation part 310, that is, the distal end of the ball falling prevention part. The plastic deformation portion 310 has a cylindrical shape before the plastic processing process, and when the end portion 300 of the plastic deformation portion 310 is closed through the plastic processing process, the diameter of the end portion becomes smaller after the plastic processing process. Therefore, wrinkles may occur or be folded in the circumferential direction, but as the rotation preventing part 280 is formed at the distal end 300 of the plastic deformation part 310, it absorbs the change in length that decreases in diameter so that the wrinkles are formed in the distal part 300. It can achieve the effect of preventing it from being produced.

The number of rotation preventing portions 280 and the depth of the groove may be determined in proportion to the circumferential length of the distal portion 300 that is reduced as it is constricted during plastic processing.

When the ball joint is manufactured through a normal process, the plastic deformation part 310 is not exposed to the outside of the ball seat 240 covered above the rotation prevention part 280 as shown in FIG. 8A. . However, there is a case that the plastic processing process is omitted due to external factors, and in this case, it is impossible to confirm whether the plastic processing has been performed properly due to the ball seat 240 that is covered over the rotation preventing part 280.

Therefore, the present invention is the length (A) of the constricted end portion 300 of the plastic deformation portion 310 as shown in Figure 8 (a) is the ball seat 240 covering the top of the rotation preventing portion 280 ) To be formed larger than the thickness (B) of the plastic deformation portion 310 as shown in Figure 8 (b) when the plastic deformation portion 310 is not plastic processed A part of the distal end 300 is exposed to the outside of the ball seat 240 so that the operator can easily determine whether plastic processing is defective.

11 is another embodiment of the ball drop-out preventing portion and the rotation preventing portion, showing a case where a cutout groove 311 is formed at the end of the plastic deformation portion 310. The incision groove 311 may be pre-processed before plastic processing, or may be formed while punching in the plastic processing process. After plastic deformation, as shown in (b) of FIG. 11, a cutout groove 311 is formed between the ball drop-out prevention part 290, and the occurrence of wrinkles as described above is prevented due to the cutout groove 311, In addition, it is possible to achieve an effect of preventing the ball seat 240 from rotating while the injection product of the ball seat 240 flows into the cutout groove 311 and solidifies.

The ball joint provided with a rotation preventing unit manufactured by the above manufacturing method includes a socket 130, ball studs 100 and 110, and a ball seat, as shown in FIG. 9.

The socket 130 plastically deforms the distal end 300 of the plastic deformation part 310 protruding opposite the ball inlet part 310 to be plastically deformed through press processing, and is closed inward, as shown in the right side (right side with respect to the center line) of FIG. Likewise, it is provided by forming a rotation preventing part 280.

The ball studs 100 and 110 are provided with a ball part 100 and a stud part 110 and are installed in the socket 130.

In the ball seat, an injection molded product is injected into the socket 130 while the ball studs 100 and 110 are installed in the socket 130, and the rotation preventing unit 280 as shown in the left (left with respect to the center line) in FIG. ) In the ball portion 100, the cap and the ball seat 240 surrounding the lubrication sheet 260 is formed.

Although the present invention has been illustrated and described with reference to specific embodiments, it is understood in the art that the present invention can be variously improved and changed within the scope of the technical spirit of the present invention provided by the following claims. It will be obvious to a person of ordinary knowledge.

100: bowl
110: stud
115: inner core
120: inner core receiving portion
130: socket
131: first opening
132: second opening
140: first mold
150: socket receptacle
160: ball stud receiving portion
170: second mold
180: second mold body
185: core receiving portion
190: plastic processing core
195: plastic processing part
200: sliding core
210: injection melt injection unit
220: coil spring
230: injection cavity space
240: ball seat
250: cap
260: lubrication sheet
270: wing part
280: anti-rotation unit
290: ball dropping prevention part
300: distal end
310: plastic deformation part
311: incision groove
320: tip portion
330: gate receiving portion

Claims (9)

Providing a ball stud having a ball portion and a stud portion;
Providing a socket having the first opening, a second opening having a plastic deformation portion protruding opposite the first opening, and a ball receiving portion having an accommodation space for accommodating the ball;
Positioning the socket in a first mold;
Inserting the stud part of the ball stud through the second opening, placing the ball part in the ball receiving part, and placing the ball stud in the first mold;
A plastic working step of plastically deforming a distal end of the plastically deformed portion of the socket to form a ball drop-out prevention portion as the second mold is mold-closed with the first mold; And
Injecting an injection melt in a state in which the first mold and the second mold are mold-closed, and inserting the melt into the ball drop-out preventing part while injection molding a ball seat surrounding at least a part of the ball part
Ball joint manufacturing method provided with a ball drop-off prevention unit comprising a. The method of claim 1,
A method of manufacturing a ball joint having a ball drop prevention part, characterized in that a wrinkle prevention structure is formed at the distal end of the ball drop prevention part. The method of claim 1,
The ball joint manufacturing method provided with a ball drop-off prevention portion in the plastic deformation portion, the length of the constricted end portion is formed larger than the thickness of the ball sheet covered over the ball drop-off prevention portion. The method of claim 1,
The second mold is:
A second mold body molded with the first mold and including a core receiving portion;
It is installed so as to be movable up and down in the second mold body, and an injection cavity space is formed at an upper portion and a lower portion of the gate accommodating space, and the ball dropout prevention unit or the rotation prevention unit is fired in the injection cavity space. A plastic processing core having a plastic processing portion formed by deformation; And
Injection melt injection unit installed in the gate receiving space
Ball joint manufacturing method provided with a ball drop-off prevention unit comprising a. The method of claim 4,
The plastic processing core is provided with a first inclined surface on the top,
The second mold,
A sliding core that includes a second inclined surface that interacts while being in contact with the first inclined surface so that the plastic processing core is moved from a first height to a second height, and is moved left and right; And
An elastic member installed in the first mold body to elastically support the movement of the plastic processing core
Ball joint manufacturing method provided with a ball drop-off prevention unit further comprising a. The method of claim 1,
The first mold is:
A socket receiving portion for receiving a socket;
Ball stud receiving portion formed through the center of the socket receiving portion so that the stud portion of the ball stud is inserted
Ball joint manufacturing method provided with a ball drop-off prevention unit comprising a. The method of claim 1,
Before the injection molding step of the ball seat,
And installing a lubricating sheet to surround at least a portion of the ball portion of the ball stud and installing a cap surrounding the aspherical surface of the ball portion. A socket having a first opening, a second opening in which a ball drop-out prevention part is formed while the distal end of the plastic processing part protruding opposite the first opening is plastically deformed and constricted, and a ball receiving part having an accommodation space for receiving the ball ;
A ball stud having a ball portion and a stud portion, and installed in the socket; And
In the state where the ball stud is installed in the socket, an injection-molded product is injected into the socket so that an injection-molded product is introduced into the ball drop-out prevention part or the rotation prevention part, and a ball seat formed surrounding the ball part
Ball joint provided with a ball drop prevention unit comprising a. In the mold apparatus for a ball joint comprising a first mold and a second mold for manufacturing a ball joint,
The first mold includes: a socket receiving portion for receiving a socket;
And a ball stud receiving portion formed through the center of the socket receiving portion so that the stud portion of the ball stud is inserted,
The second mold may include a second mold body that is molded with the first mold and includes a core accommodation space;
A plasticizer that is installed to be movable up and down in the second mold body, has a gate accommodation space at the top and an injection cavity space at the bottom of the gate accommodation space, and plastically deforms the ball dropping prevention part in the injection cavity space Plastic processing core with study formed; And
Injection melt injection unit installed in the gate receiving space
A mold apparatus for a ball joint provided with a ball drop prevention unit comprising a.

Images