WIDE ANGLE JOINT AND STEERING DEVICE USING THE SAME

Technical Field

The present invention relates to a wide angle joint and a steering device using the wide angle joint, in particular, to a wide angle joint that is easier to manufacture and assemble than a universal joint and has a power transmission angle over 90° when it is bent, and a steering device using the wide angle joint for a vehicle.

Background Art

In general, when it is required to bend a shaft that transmits power, such as a steering device, a universal joint is used at the bend of the shaft to transmit the power. FIG. 1 is a perspective view of a universal joint in the related art.

As shown in FIG. 1, when the universal joint is bent at a predetermined angle, a driving shaft 10 and a driven shaft 20 are connected by a center piece 30, with yokes 12 and 22 of the shafts cross at 90°.

In a universal joint having the above structure, an allowable power transmission bending angle is generally about 35° or less. The main concern in a wide angle joint is to increase the bending angle; however, in a wide angle joint, it is only possible to transmit power within a range

of about 60 to 70°.

Further, although the structure of a universal joint is simple and it is easy to manufacture the universal joint as compared with a gear box, the structure is complicated as compared with a general joint for power transmission, such that manufacturing and assembling are difficult.

In particular, a universal joint having the function of a wide angle joint by inserting a coupling yoke between two yokes has a very complicated structure. When the direction of power transmission is changed by a gear box, it is favorable for constant transmission, but the structure becomes complicated. As a result, manufacturing cost is increased and it is difficult to change the bending angle once determined.

Disclosure of the Invention

The invention is designed to overcome the above problems and it is an object of the invention to provide a wide angle joint that can transmit power, even if more than 90° by improving the allowable power transmission bending angle when it is bent and a steering device for a vehicle using the wide angle joint.

It is another object of the invention to provide a wide angle joint that has a simple structure and is easy to manufacture, assemble, and maintain, and a steering device

for a vehicle using the wide angle joint.

It is another object of the invention to provide a wide angle joint that is easy to adjust a bending angle and a steering device for a vehicle using the wide angle joint. In order to accomplish the above objects, a wide angle joint for transmitting power from a driving shaft to a driven shaft according to an embodiment of the invention, comprises: a driving rotary plate mounted at the end of the driving shaft; a plurality of first insertion holes formed through the driving rotary plate; a driven rotary plate mounted at the end of the driven shaft; a plurality of second insertion holes formed through the driven rotary plate; and links having bends curved at a predetermined angle, of which an end is slidably inserted into the first insertion hole and the other end is slidably inserted into the second insertion hole.

The bend may be formed in a hinge structure or the bend may be formed in the shape of a flexible corrugated pipe.

Further, a bearing may be provided in the insertion hole to assist sliding of the link.

In order to accomplish another object, a steering device for a vehicle includes: the above wide angle joint; a steering column mounted through a dash panel of a vehicle and connected with the driving shaft of the wide angle joint; and a gear box connected to the driven shaft of the

wide angle joint.

Brief Description of the Drawings

FIG. 1 is a perspective view of a universal joint in the related art;

FIG. 2 is a perspective view of a wide angle joint according to an embodiment of the invention;

FIG. 3 is an exploded perspective view of a wide angle joint according to an embodiment of the invention; FIGS. 4A to 4D are views illustrating the operation of a wide angle joint according to an embodiment of the invention;

FIG. 5 is a perspective view of a wide angle joint according to another embodiment of the invention; FIG. 6 is a perspective view of a wide angle joint according to another embodiment of the invention; and

FIG. 7 is a view showing a wide angle joint in operation according to another embodiment of the invention.

Best Mode for Carrying Out the Invention

Hereinafter, an exemplary embodiment of the invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a perspective view of a wide angle joint according to an embodiment of the invention and FIG. 3 is an

exploded perspective view of the wide angle joint.

Referring to FIG. 3, a wide angle joint according to an embodiment of the invention includes a driving shaft 40 that transmits power and a driven shaft 50 that receives the power, and the driving shaft 40 is connected with a driven shaft 50 by links 60 that are bent at a predetermined angle.

In detail, a driving rotary plate 42 with a plurality of first insertion holes 44 is mounted at an end of the driving shaft 40 and a driven rotary plate 52 with a plurality of second insertion holes 54 is mounted at an end of the driven shaft 50. The driving shaft 40 and the driven shaft 50 are connected by slidably inserting one end of the links 60 having bends 62 that are curved at a predetermined angle into the first insertion holes 44 of the driving rotary plate 42 and the other end into the second insertion holes 54 of the driven rotary plate 52.

FIGS. 4A to 4D illustrate the principle of power transmission of the wide angle joint according to an embodiment of the invention. For convenience of description, it is assumed that one link is used.

Referring to FIGS. 4A to 4D, as shown in FIG. 4A illustrating the first step, as the driving shaft 40 rotates in direction A, the driving rotary plate 42 rotates in the same direction and the link inserted in the first insertion hole 44 moves in +X-axis direction and -Z-axis

directionsimultaneousIy.

When the link 60 moves in +X-axis direction, the portion inserted in the driven rotary plate 52 correspondingly moves in +X-axis direction. The link 60 inserted in the second insertion hole 54 of the driven rotary plate 52 moves in the same direction of the rotational direction of the driven shaft 50 in the XY plane and can freely move in the Z-axis direction. Therefore, the link 60 moves in +X-axis direction and +Y-axis direction in the XY plane simultaneously and, as shown in FIG. 4A illustrating the first step, the driven rotary plate 52 and the driven shaft 50 rotate in direction B.

When the driving shaft 40 rotates at 90°, the link 60 reaches the position shown in FIG. 4B illustrating the second step. Further, as the driving shaft 40 continues to rotate, the portion of the link 60 inserted in the first insertion hole 44 of the driving rotary shaft 42 moves in - Z-axis direction and -X-axis direction and the portion inserted in the second insertion hole 54 of the driven rotary plate 52 moves in +Y-axis direction and -X-axis direction. As a result, the link 60 reaches the position shown in FIG. 4C illustrating the third step.

Repeating the above operation, the link 60 returns to the initial position through the fourth step, and while the driving shaft 40 makes one rotation and the driven shaft 50

connected at a predetermined angle correspondingly makes one rotation.

When one link is used, a singular point may exist at the position shown in the second step, where the driven shaft may rotate in two directions, i.e. +B direction or -B direction due to the rotation of the driving shaft.

Therefore, it is required to make the driven shaft rotate in a predetermined direction, using a plurality of links connecting the two shafts or a specific auxiliary device. When two links are used, the center of the shaft and the insertion holes should not make an angle of 180°.

Because the link is bent, it transmits power while being bent at a predetermined angle between the driving shaft and the driven shaft. As shown in FIG. 2, that is, the link can transmit power at 90°and more than 90° and the angle between the driving shaft and the driven shaft can be adjusted, depending on the degree of the bend of the link.

It may be possible to fix the angle of the bend, but also to allow the adjustment of the angle. FIGS. 5 and 6 are perspective views of a wide angle joint including a link having a variable angle of bend.

As shown in FIG. 5, a hinge may be applied to a bend 62, such that the bend 62 can be changed to have a desired angle, depending on the condition of the space which the joint is mounted to.

According to a wide angle joint of another embodiment of the invention, as shown in FIG. 6, a bend 62 of a link is formed in the shape of a flexible corrugated pipe. According to this configuration, as shown in FIG. 7, it is possible to freely change the angle of the bend, such that mounting and assembling at a desired space can be simple.

As described above, since the link is slidably inserted into the insertion holes of each of the rotary plate, it is more preferable to provide a bearing in the insertion hole to smoothly slide the link.

The wide angle joints according to embodiments of the invention can be applied to various parts that are required to transmit power at a predetermined angle, and particularly, utilized more effectively in the steering device of vehicles, such as a car.

A wide angle joint according to an embodiment of the invention can be used, instead of a universal joint, by connecting the driving shaft of the wide angle joint to the steering column mounted through the dash panel of a vehicle and the driven shaft to the gear box.

When a wide angle joint according to an embodiment of the invention is substituted for a universal joint, because the structure is simpler than universal joints of the related art, it is possible to easily machine, manufacture, and assemble, while reducing the causes of problems of a

wide angle joint. Furthermore, fixing the wide angle joint is simple, even if it is broken, such that maintenance be also simplified.

Accordingly, the wide angle joint can be manufactured and maintained at low cost with high economical efficiency.

In addition to the steering device of a vehicle, a wide angle joint according to an embodiment of the invention may be effectively applied to power transmission in agricultural implements, such as a cultivator, particularly when separate output power is required for farming.

As described above, a wide angle joint according to an embodiment of the invention and a steering device for a vehicle using the wide angle joint can considerably increase the bending angle as compared with universal joints in the related art.

Further, a wide angle joint according to an embodiment of the invention and a steering device for a vehicle using the wide angle joint are easy to manufacture, assemble, mount, and maintain, and have high economical efficiency as compared with universal joints in the related art.

Further, a wide angle joint according to an embodiment of the invention has the effect of saving cost and mounting time by applying it to the steering wheel of a vehicle, and can be simply applied to a variety of power transmissions. The foregoing embodiments are illustrative of a wide

angle joint according to the invention. Further, the invention is not limited to the embodiments, and those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Industrial Applicability

According to a wide angle joint of an embodiment of the invention and a steering device of a vehicle, it is easy to manufacture and assemble, as compared with universal joints in the related art, and it is possible to change the power transmission angle by 90° or more while the wide angle joint is bent.