TWI440778B - Ball joint - Google Patents

Description

Ball joint

The invention relates to a ball joint.

In order to realize the pivoting of the plural direction, the universal joint is often used for articulation in toys, robots and the like. The traditional universal joint system consists of two connecting blocks and a cross shaft. The application of the cross shaft makes the moving angle of the universal joint small, the work is not stable enough, and it also has the disadvantages of low rigidity and short life when operating at large angles.

To overcome the above shortcomings, ball joints are widely used. However, in the ball joint, the ball head and the spherical shell covering the ball head can only rotate relative to each other, and the torque cannot be transmitted. Therefore, if the ball joint is to transmit torque, it is necessary to add a pin or the like to restrict the ball. The rotation of the head joint in a certain direction increases the components and makes the structure complicated. At the same time, due to the corresponding structure of the pin hole and the like, the smooth spherical surface of the ball head is destroyed, and the ball head and the spherical shell are relatively rotated. It is easier to wear.

In view of the above, it is necessary to provide a ball joint that can transmit torque and has a simple structure.

a ball joint, comprising a ball head and a spherical shell coated on the ball head, the ball head being an ellipsoid, the ball joint further comprising a connecting portion connected to the ball head and perpendicular to the long axis of the ball head, the spherical shell forming An ellipsoidal ball socket, the ball joint further comprising a connecting arm connected to the spherical shell and perpendicular to the long axis of the ellipsoidal ball socket, the ball head having an ellipsoidal ball relative to the spherical shell a long axis of the head and two rotational degrees of freedom perpendicular to the minor axis of the connecting portion, the spherical shell comprising a first housing and a second housing, the first housing having a receiving cavity, the second housing also having The accommodating cavity is formed by the accommodating cavity of the first casing and the accommodating cavity of the second casing, the second casing has a joint surface, and the accommodating cavity of the second casing is combined with the joint An elliptical notch is formed on the surface, and the shape and size of the notch are consistent with the shape and size of the ball head.

Another ball joint includes a ball head and a spherical shell coated on the ball head, the ball head having a first rotation axis and a second rotation axis perpendicular to each other, passing through the center of the ball head and perpendicular to the cross section of the first rotation axis The area is different from the area of the section passing through the center of the ball head and perpendicular to the second axis of rotation, the ball joint further comprising a joint connected to the ball head and perpendicular to the first axis of rotation and the second axis of rotation, the ball shell forming the ball a socket having a shape corresponding to the ball head, the ball head having two rotation degrees of rotation with respect to the spherical shell about the first rotation axis and the second rotation axis, the spherical shell including the first casing and the second casing, The first housing has a receiving cavity, and the second housing also has a receiving cavity formed by the receiving cavity of the first housing and the receiving cavity of the second housing. The second housing The body has a bonding surface, and the receiving cavity of the second casing forms an elliptical notch on the bonding surface, and the shape and size of the notch are consistent with the shape and size of the ball head.

In the ball joint, the area of the cross section passing through the center of the ball head and perpendicular to the first rotary axis is different from the area of the center of the ball passing head and perpendicular to the second rotating shaft, so the ball head cannot be wound around the spherical shell. The connecting part rotates to achieve the purpose of transmitting torque. The structure does not need to add additional components, the structure is simple, and there is no need to open a hole in the ball head, so that the surface of the ball head is smooth, and the wear of the ball head relative to the rotation of the spherical shell is reduced. .

100‧‧‧Ball joints

10‧‧‧First pivoting body

30‧‧‧Second pivot body

11‧‧‧ ball head

13‧‧‧ neck

15‧‧‧Connecting Department

A‧‧‧ long axis

b‧‧‧Short axis

151‧‧‧ Ring groove

153‧‧‧connection hole

31‧‧‧Spherical shell

33‧‧‧Connecting arm

311‧‧‧ first housing

313‧‧‧Second housing

315‧‧‧fasteners

3111‧‧‧容容

3113‧‧‧ openings

3115, 3137‧‧‧ Installation Department

3131‧‧‧ joint surface

3133‧‧‧容容

3135‧‧‧ notch

3151‧‧‧ screws

3153‧‧ ‧ pin

317‧‧‧ ball nest

331‧‧‧ Ring groove

333‧‧‧connection hole

1 is an assembled view of a ball joint of an embodiment of the present invention.

Figure 2 is an exploded view of the ball joint of Figure 1.

Figure 3 is a cross-sectional view of the ball joint of Figure 1 taken along line III-III.

Figure 4 is a cross-sectional view of the ball joint of Figure 1 taken along line IV-IV.

Figure 5 is a cross-sectional view of the ball joint of Figure 1 taken along line V-V.

The ball joints provided by the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

Referring to FIGS. 1 and 2 , the ball joint 100 includes a first pivoting body 10 and a second pivoting body 30 rotatably coupled to the first pivoting body 10 .

3 to 5, the first pivoting body 10 includes a ball head 11, a neck portion 13 connected to the ball head 11, and a connecting portion 15 connected to the neck portion 13. In the present embodiment, the ball head 11 is an ellipsoidal shape having an elliptical cross section at a maximum circumference and perpendicular to the connecting portion 15 and having a major axis a and a minor axis b perpendicular to each other, perpendicular to the long axis a The cross section is circular. Wherein, the length of the major axis a is L1, the length of the minor axis b is L2, L1 is greater than L2, and the cross section perpendicular to the major axis a is a circle having a radius equal to L2. The neck portion 13 has an outer diameter smaller than that of the ball head 11 and the connecting portion 15. The connecting portion 15 is a hollow rotating shaft, and has two ring grooves 151 and two connecting holes 153 formed on opposite sides of the connecting portion 15. The two connecting holes 153 are in communication with one of the ring grooves 151. In the first pivoting body 10, the neck portion 13 and the connecting portion 15 are both perpendicular to the plane in which the major axis a and the minor axis b of the ball head 11 are located. Of course, the cross section of the ball head 11 perpendicular to the long axis a may also be an ellipse having a long axis equal to L2. It can be understood that the number of the ring grooves 151 is not limited to two, and may be other numbers such as one, three, and the like. The ring groove 151 is for accommodating a sealing member (not shown) or a lubricant, and the connecting hole 153 is for connecting the first pivoting body 10 with other members.

The second pivoting body 30 includes a spherical shell 31 and a connecting arm 33 connected to the spherical shell 31. The spherical shell 31 is a split structure including a first housing 311, a second housing 313, and a fastener 315. A fastener 315 is used to connect the first housing 311 to the second housing 313.

The first housing 311 is a partial hemispherical shell, and one side is recessed to form a receiving cavity 3111, and the other side is opened with an opening 3113. The opening 3113 is in communication with the receiving cavity 3111. A mounting portion 3115 for mounting the fastener 315 is formed outside the first housing 311. The second housing 313 is substantially a semi-spherical spherical shell having a bonding surface 3131. The second housing 313 is further provided with a receiving cavity 3133. The receiving cavity 3133 forms a notch 3135 at the bonding surface 3131, and the second housing A mounting portion 3137 for mounting the fastener 315 is also formed on the outer side of the 313. The notch 3135 of the second casing 313 is an ellipse and the lengths of the major axis and the minor axis are respectively equal to the lengths L1, L2 of the major axis a and the minor axis b of the ball head 11 of the first pivoting body 10. In the spherical shell 31, the first housing 311 is fastened to the joint surface 3131 of the second housing 313, and the accommodating cavity 3111 of the first housing 311 and the accommodating cavity 3133 of the second housing 313 form an ellipsoidal ball. The socket 317 is connected to the outside by the opening 3113 of the first housing 311. In this embodiment, the fastener 315 includes two screws 3151 and two pins 3153. Accordingly, the outer sides of the first housing 311 and the second housing 313 respectively form four mounting portions 3115, 3137, and the mounting portion 3115 and the mounting portion The portions 3137 are evenly arranged in the circumferential direction on the outer side of the first casing 311 and the outside of the second casing 313, respectively. The screw 3151 and the pin 3153 are attached to the mounting portion 3115 and the mounting portion 3137 at intervals.

The connecting arm 33 is a hollow rotating shaft connected to the spherical shell 31 and perpendicular to the long axis and the short axis of the ball socket 317. The connecting arm 33 is provided with a ring groove 331 and two connecting holes on opposite sides of the connecting arm 33. 333, and the connecting hole 333 is in communication with a ring groove 331. It can be understood that the number of the ring grooves 331 is not limited to two, and may be other numbers such as one, three, and the like. The ring groove 331 is for accommodating a sealing member (not shown) or a lubricant, and the connecting hole 333 is for The pivoting body 30 is coupled to other components.

When the ball joint 100 is assembled, the ball head 11 of the first pivot body 10 is inserted into the accommodating cavity 3133 of the second casing 313 of the spherical shell 31 of the second pivot body 30, and the second pivot body is The first housing 311 of the spherical shell 31 of the 30 is sleeved on the ball 11 from the connecting portion 15 of the first pivoting body 10, and the first housing 311 and the second housing 313 are locked by the fastener 315. Assembly of the ball joint 100. The periphery of the ball head 11 is in close contact with the portion of the first housing 311 and the second housing 313 which are adjacent to the gap therebetween, and the ball head 11 is away from one end of the connecting portion 15 and the inner wall of the second housing 313 With a gap.

When the ball joint 100 is used, the connecting portion 15 of the first pivoting body 10 or the connecting arm 33 of the second pivoting body 30 is biased, so that the ball 11 can be wound around the spherical shell 31 in the ball socket 317. The short axis b of the head 11 rotates or rotates about the long axis a of the ball head 11 to achieve pivoting of a plurality of angles. The ball head 11 has two rotational degrees of freedom about the short axis b and the major axis a with respect to the spherical shell 31. When the torque is applied to the connecting portion 15 of the first pivoting body 10 or the connecting arm 33 of the second pivoting body 30, since the ball head 11 is elliptical, it cannot rotate relative to the spherical shell 31 around the connecting portion 15, and thus Torque is transmitted by the ball joint 100. There is no need to add additional positioning elements to limit its rotation around the connecting portion 15, the structure is simple, and the structure does not need to be opened in the ball head 11, ensuring that the surface of the ball head 11 is continuously smooth, effectively reducing the wear during rotation.

In the ball joint 100, the spherical shell 31 is provided in a split structure, which is convenient for manufacture and assembly. A gap is formed between the ball end 11 away from the end of the connecting portion 15 and the inner wall of the second casing 313 of the spherical shell 31, so that the friction of the ball head 11 relative to the rotation of the second casing 313 can be reduced, and the rotation can be smoothly performed. Effectively reduce wear.

The ball head 11 and the connecting portion 15 of the first pivoting body 10 are connected by the neck portion 13 having a smaller diameter, so that the outer side of the connecting portion 15 can be prevented from hitting the opening 3113 of the first casing 311 of the spherical shell 31. The edges interfere with the normal rotation of the ball head 11.

The annular groove 151 on the connecting portion 15 and the annular groove 331 on the connecting arm 33 can accommodate a seal or a lubricant, ensure stability when connected to other components, or ensure sufficient lubrication when the component is rotated. The connecting hole 153 communicates with the ring groove 151, and the connecting hole 333 communicates with the ring groove 331, so that the lubricant can lubricate the elements connected to the connecting hole 153 and the connecting hole 333.

It can be understood that the ball head 11 can also be other shapes than the ellipsoidal shape, and only the ball head 11 has a first rotation axis and a second rotation axis perpendicular to each other, and passes through the center of the ball head 11 and is vertically the first time. The area of the cross section of the rotating shaft may be different from the area of the cross section passing through the center of the ball head 11 and perpendicular to the second rotating shaft, such as a cylinder which is processed into a hemispherical shape at both ends.

The fastener 315 of the spherical shell 31 can also be omitted, and the first housing 311 and the second housing 313 can be engaged by a structure such as a claw.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. However, the above is only a preferred embodiment of the present invention, and equivalent modifications or variations made by those skilled in the art will be included in the following claims.

100‧‧‧Ball joints

10‧‧‧First pivoting body

30‧‧‧Second pivot body

11‧‧‧ ball head

13‧‧‧ neck

15‧‧‧Connecting Department

151‧‧‧ Ring groove

153‧‧‧connection hole

31‧‧‧Spherical shell

33‧‧‧Connecting arm

311‧‧‧ first housing

313‧‧‧Second housing

315‧‧‧fasteners

3111‧‧‧容容

3113‧‧‧ openings

3115, 3137‧‧‧ Installation Department

3131‧‧‧ joint surface

3133‧‧‧容容

3135‧‧‧ notch

3151‧‧‧ screws

3153‧‧ ‧ pin

331‧‧‧ Ring groove

333‧‧‧connection hole

Claims (7)

A ball joint comprising a ball head and a spherical shell coated on the ball head, the improvement being that the ball head is an ellipsoid, the ball joint further comprising a long axis connected to the ball head and the ball head a vertical connecting portion, the spherical shell forming an ellipsoidal ball socket, the ball joint further comprising a connecting arm connected to the spherical shell and perpendicular to a long axis of the ellipsoidal ball socket, the ball head having a spherical body opposite to the spherical shell a second axis of rotation about the long axis of the ellipsoidal ball head and a minor axis perpendicular to the connecting portion, the spherical shell comprising a first housing and a second housing, the first housing having a receiving cavity The second housing also has a receiving cavity formed by the receiving cavity of the first housing and the receiving cavity of the second housing, the second housing having a bonding surface, the second housing The accommodating cavity forms an elliptical notch on the bonding surface, and the shape and size of the notch are consistent with the shape and size of the ball head. The ball joint according to claim 1, wherein the ball head has a gap between one end of the ball joint and the inner wall of the ball socket. The ball joint according to claim 1, wherein the first casing further forms an opening away from a side of the second casing, and the ball socket communicates with the outside through the opening. The ball joint according to claim 1, wherein the connecting portion and the connecting arm are provided with a ring groove and a connecting hole, and the ring groove and the connecting hole communicate with each other. A ball joint comprising a ball head and a spherical shell coated on the ball head, wherein the ball head has a first rotation axis and a second rotation axis perpendicular to each other, passing through the center of the ball head and perpendicular thereto The area of the cross section of the first rotary axis is different from the area of the cross section passing through the center of the ball head and perpendicular to the second rotary axis, the ball joint further comprising a ball joint connected to the ball head and perpendicular to the first rotary axis a connecting portion of the second rotating shaft, the spherical shell forming a ball socket having a shape corresponding to the ball head, the ball head having a rotation relative to the spherical shell about the first rotating shaft and the second rotating shaft Rotational freedom, the spherical shell includes a first housing and a second housing, the first housing having The accommodating cavity has a receiving cavity formed by the accommodating cavity of the first casing and the accommodating cavity of the second casing, the second casing having a joint surface, The accommodating cavity of the second casing forms an elliptical notch on the joint surface, and the shape and size of the notch are consistent with the shape and size of the ball head. The ball joint of claim 5, wherein the ball head is ellipsoidal, and the first and second rotary axes are the major and minor axes of the ball. The ball joint of claim 5, wherein the ball joint further comprises a connecting arm coupled to the ball shell.