JPS6347928B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a link mechanism for driving wipers for automobiles, and more specifically to a structure of a ball joint that transmits the driving force of a motor to left and right wipers.

FIG. 3 is a schematic side view of a conventional link assembly 10. The flat plate-shaped link 11 has holes bored at both ends. One end of the drive shaft 13 is press-fitted into one hole and the end is tightened to fix the drive shaft 13 to the link 11. A link assembly 10 is constructed by attaching a ball joint 12. Then, driving force is transmitted from the motor to the drive shaft 13 of the link assembly 10 through various link mechanisms (not shown), and the drive shaft 13 is rotated in forward and reverse directions as shown by the arrows, thereby rotating the ball joint 12. each joint ball 12
Link members attached to a and 12b (not shown)
This reciprocates the left and right wipers (not shown), respectively. FIG. 4 is a schematic diagram illustrating a method of attaching the ball joint 12 to the link 11, and FIG. 5 is a schematic front view of the link assembly 10. Ball joint 12
has approximately spherical joint balls 1 at both ends in the axial direction.
2a and 12b are formed, and a serration 12d is formed uniformly in the circumferential direction between them. The serrations 12d have their unevenness extended in the axial direction of the ball joint 12, and the serrations 12d
A stopper 12c having a larger diameter than the serrations 12d is formed adjacent to the end surface on the side of the joint ball 12a. And joint ball 12b
The diameter of is the serration 12 formed in the shape of a circumferential surface.
The ball joint 12 is inserted from the joint ball 12b side into the link hole 11a of the link 11, which is smaller than the circumferential diameter of the serration 12d and has a diameter substantially the same as the circumferential diameter of the serration 12d.
d into the link hole 11a, the serration 12d slightly protruding from the link 11, and the recesses 12e provided at several locations in the circumferential direction.
A ball joint 12 was fixed to a link 11. Such a ball joint 12 is integrally molded and has an extremely complicated shape, so each joint ball 12a, 1
2b, serrations 12d, etc. require cutting, which poses a major problem in terms of processing cost. Furthermore, it is preferable that the joint ball to which the torque of the motor is applied has a large diameter in order to minimize the surface pressure, but the joint ball 12b
needs to be smaller in diameter than the diameters of the link hole 11a and the serrations 12d, and since the size of the link 11 is limited by its installation space, the joint ball 12b is smaller than the diameter of the joint ball 12a.
Similarly, the problem was that it could not be made sufficiently large and a large torque motor could not be used.
Furthermore, in order to set the serration 12d, it is necessary to avoid the joint ball 12b, but when the joint ball 12b and the serration 12
Since the difference in diameter d is extremely small for the reasons mentioned above, it is difficult to attach the ball joint 12 to the link 11, and strict control of the dimensional accuracy of the fitting device is required.

The present invention has been developed in view of the above points, and it is possible to reduce the processing cost by omitting the cutting process, and to make the joint balls into large spherical shapes with the same diameter without being restricted by the diameter of the joint balls. Another object of the present invention is to provide a ball joint in which the joint member can be easily attached to the link. The present invention relates to a structure of a ball joint used in a link connection part of an automobile wiper drive mechanism, etc., in which a pin is inserted through a through hole of a predetermined diameter drilled in a carrier such as a link, and the pin has a substantially spherical shape. This paper proposes a ball joint structure characterized by a pair of jointed balls fixed together.

Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic side view showing a first embodiment of the link assembly 1 of the present invention, and FIGS. 2 a to 2 c are schematic diagrams illustrating a method of attaching the ball joint 3 to the link 2. The link 2 has a flat plate shape with a hole bored in one end thereof, and one end of the drive shaft 4 is press-fitted into this hole and the end is tightened to fix the drive shaft 4 perpendicularly to the link 2. . Link 2
A link hole 2a is bored at the other end, and a ball joint 3 consisting of joint balls 3a and 3b and a pin 3c is attached by inserting the pin 3c into the link hole 2a. That is, the pin 3c has a cylindrical shape with an appropriate diameter, and the pin 3c and the substantially spherical joint ball 3a having an arbitrary diameter are integrally formed by cold forging or the like. The joint ball 3b is approximately spherical and has an arbitrary diameter, and is formed separately from the joint ball 3a and pin 3c by cold forging or the like. The joint ball 3b has a ball hole 3d having a diameter slightly larger than the diameter of the pin 3c, which is formed approximately through the center of the joint ball 3b.
Further, the opposite end of the link 2 in the spherical joint ball 3b is formed with a flat surface perpendicular to the ball hole 3d, as if a part of the ball was removed, and the end of the ball hole 3d on the flat surface side. The portion is so-called chamfered to form a tapered portion 3e. Note that the diameter of the link hole 2a of the link 2 is approximately the same as the diameter of the pin 3c.

Therefore, when attaching the ball joint 3 as described above to the link 2, as shown in FIG. 2b, a pin 3c having a joint ball 3a integrally formed at one end thereof is used.
is first press-fitted into the link hole 2a from the other end side. Next, the pin 3c protruding from the link 2 is inserted into the ball hole 3d of the joint ball 3b.
The length of the pin 3c is such that it protrudes an appropriate length from the joint ball 3b when the joint ball 3b is fitted, and as shown in FIG.
The pin 3c is fixed to the joint ball 3b by, for example, spinning the protruding portion of the pin 3c. The fitting part 3f protrudes slightly from the flat surface of the joint ball 3b, but the joint ball 3b
Since it falls within the spherical surface regulated by the diameter of
When a link member (not shown) connected to the wiper is fitted to the joint ball 3b, sliding contact between the link member and the joint ball 3b is not obstructed. Note that the tapered portion 3e of the ball hole 3d formed on the flat surface side of the joint ball 3b has a high locking effect and firmly fixes the pin 3c and the joint ball 3b, making it possible to control the shape of the bent portion 3f. However, it is of course not necessary to provide such a tapered portion 3e in view of the strength of attachment of the ball joint 3 to the link 2.

The joint member 3 attached to the link 2 as described above has a link member connected to the left or right wiper fitted in the joint balls 3a and 3b so as to be able to slide into it, and receives the driving force from the motor in various ways, for example. When the link mechanism transmits the power to the drive shaft 4 of the link assembly 1, and the drive shaft 4 is rotated forward and backward as shown by the arrow (see Fig. 1), the link 2 makes a pendulum motion around the drive shaft 4. joint ball 3
a and 3b cause the wiper to reciprocate.

Therefore, each joint ball 3a and 3b does not need to be inserted through the link hole 2a during installation, so it can be made to any size, and each joint ball has a size sufficient to keep the surface pressure small. It can be made into a large shape and therefore a high torque motor can be used to drive the wiper. In addition, by applying nickel plating or the like to the surfaces of the joint balls 3a and 3b, it is possible to improve the corrosion resistance thereof, and also to improve the sliding property of the link member fitted to the joint balls 3a and 3b. I can do it. The ball joint 3 has an extremely simple structure, and since the joint ball 3b, the joint ball 3a, and the pin 3c are made separately, they can be easily manufactured by head processing such as cold forging, Since there is no need to cut the serrations as shown in the figure, the processing cost is low. In addition, the pin 3c can be fixed to the joint ball 3b by normal spinning processing, and there is no need to use a high-precision specific jig as in the conventional method. Easy to install. Furthermore, the ball joint 3 has a pin 3c.
Since the ball joint 3 is positioned by press-fitting into the link hole 2a, the ball joint 3 can be attached to the link 2 with high precision.

As explained in detail above, the ball joint of the automobile wiper drive mechanism, etc. according to the present invention has two parts for each component of the ball joint.
Since it is divided, it is not limited by the spherical diameter of the joint ball, and can be set to the desired size determined by the motor torque, etc., and both joint balls can be made to have the same diameter. The component parts can be manufactured at low cost due to the reduction of cutting processes, etc., and can be easily attached to the link of the ball joint, and the shape of the fixing location can be finished beautifully.

It should be noted that the present invention should not be limited to the specific embodiments described above, and it goes without saying that various modifications are possible within the technical scope of the present invention.

[Brief explanation of drawings]

FIG. 1 is a schematic side view showing the first embodiment of the present invention, FIGS. 2 a to c are schematic diagrams illustrating the method of attaching the ball joint 3 to the link 2, and FIG. 3 is a conventional link assembly. 10, FIG. 4 is a schematic diagram illustrating how to attach the ball joint 12 to the link 11, and FIG.
The figure is a schematic front view of the link assembly 10. (Explanation of symbols), 1: Link assembly, 2: Link, 2a: Link hole, 3: Ball joint, 3a, 3b:
Joint ball, 3c: pin, 3d: ball hole.

Claims (1)

[Claims] 1. In the structure of a ball joint such as an automobile wiper drive mechanism in which a pair of joint balls are provided approximately coaxially on a carrier such as a link, a through hole of a predetermined diameter is bored in the carrier and the joint balls are arranged on both sides of the carrier. A pair of joint balls provided are constructed separately, one joint ball is provided with a ball hole having a diameter substantially equal to the through hole, and the other joint ball is large enough to be inserted into these holes. A pair of joint balls are integrally provided in a protruding manner, and the integral pin is inserted into the joint ball having the ball hole following the carrier, and the ends of the pins are caulked to attach the pair of joint balls to the carrier. A structure of a ball joint characterized by being fixed to.