JPH0377093B2 - - Google Patents

Description

[Detailed description of the invention] Industrial applications The present invention relates to a wiper device for an automobile.

Prior art For example, the wiper device for automobiles is
As shown in Japanese Patent No. 157756, a wiper arm is already known in which the wiper arm is extended and retracted during the swinging process so that the wipe area of the window glass by the wiper blade can be expanded. This consists of a main arm that connects the wiper arm to the wiper pivot, and a sub-arm that is fitted to the main arm so that it can move forward and backward, and a fixed link is provided on the wiper pivot.
By connecting a rotating link across the free end of this fixed link and the sub-arm, the sub-arm is moved forward and backward during the swinging process of the wiper arm.

However, in such a conventional structure, since the sub-arm advances and retreats only one stroke with each forward or backward movement of the wiper arm, there is a natural limit to the expansion of the wiping area, and it is difficult to significantly expand the wiping area. I can't wait. In addition, since the movement of the sub-arm back and forth is performed by the bending and stretching action of the fixed link and the rotating link, in order to ensure sufficient movement of the sub-arm back and forth, the connecting length of the fixed arm and the rotating arm should be set long. There is a need. As a result, when the sub-arm is at its maximum retreat, the fixed link and rotating link are bent at a small angle and extend to the sides of the wiper arm, which only makes it difficult to arrange the wiper device on the vehicle body. This also causes a problem that the appearance becomes unsightly. In addition, since the sub-arm moves forward and backward by the bending and stretching action of the fixed arm and the rotating arm, the force acting in the direction of pressing the sub-arm against the main arm becomes large, and the sliding resistance between the sub-arm and the outer arm becomes extremely large. The smooth movement of the wiper blade, in other words, the smooth movement of the wiper blade, is hindered, resulting in a problem that the wiping performance is degraded. Also, Utsukai Showa 59-29341
The automobile wiper device disclosed in the publication was proposed in view of the above-mentioned problems, and is designed to allow the sub-arm to advance and retreat multiple times during one swinging process of the wiper arm. this is,
The pivot that connects the main arm is formed hollow, and a rotating shaft passing through the interior space of the pivot is provided.A crank is provided at the tip of this rotating shaft, and a rotating link is provided between the free end of the crank and the sub-arm. The number of times the sub-arm moves back and forth can be set by adjusting the gear ratio of the gear system that rotates the pivot and the gear system that rotates the rotating shaft on which the pivot is placed.

However, in such a structure, the pivot, which is subjected to a large load when the wiper arm swings, must be formed hollow, making it difficult to obtain sufficient strength for the pivot, which tends to cause wobbling, which also hinders the smooth movement of the wiper blade. In addition, there is a problem that a large number of gears are required to rotate the pivot and the rotating shaft, which increases the number of parts and requires an extremely large number of assembly steps.

Purpose of the Invention In view of the conventional situation, the present invention has a simple structure that allows the sub-arm to move forward and backward multiple times during the forward or backward movement of the wiper arm, thereby expanding the wiping area, as well as allowing the sub-arm to move forward and backward. The wiper blade can operate smoothly, further improving the wiping performance of the wiper blade, and the sub-arm drive mechanism does not protrude to the side of the wiper arm, making installation layout on the vehicle body easier. It is an object of the present invention to provide a wiper device for an automobile, which can be easily attached to or removed from a vehicle body, and which can improve the appearance.

Structure of the Invention In order to achieve the above object, the present invention includes the following:
A wiper arm consisting of an arm head fixed to a wiper pivot, a main arm pivotally supported by the arm head, and a sub-arm fitted to the main arm so as to be able to move forward and backward, and a fixed gear provided on the pivot bearing and meshed with the fixed gear. A sub-arm drive mechanism comprising: a gear mechanism including a driven gear; and an actuating rod having one end connected to the sub-arm and the other end connected at a position offset from the rotation center of the driven gear in the driven gear. In the wiper device, the driven gear is pivotally supported by the arm head.

Example Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In Figures 1 and 2, 1 is the wiper pivot 6
A wiper arm 1 is shown connected and fixed at the end, and this wiper arm 1 has an arm head 3 fixed to a wiper pivot 6 and a pin 5 attached to the arm head 3.
The main arm 2 is pivotally supported by a main arm 2, and a sub-arm 4 is fitted into the main arm 2 so that it can move forward and backward, and a wiper blade (not shown) is attached to the front end of the sub-arm 4. . The rear end of the main arm 2 is rotatably connected to an arm head 3 by a pin 5, and the arm head 3 is serration-fitted to a wiper pivot 6 and fixed by tightening a nut 7. A spring 9 is stretched across a portion of the arm head 3 that is offset below the connecting pin 5 and the middle portion of the main arm 2, and this spring 9 urges the wiper arm 1 downward from the connecting portion of the arm head 3. The above-mentioned wiper blade is pressed against a window glass surface (not shown). Reference numeral 10 indicates a drive mechanism for the sub-arm 4, and the drive mechanism 10 includes a gear mechanism 11 and a gear mechanism 11.
The actuating rod 12 converts the rotational movement of the sub-arm 4 into the linear movement of the sub-arm 4. The gear mechanism 11 includes a fixed gear 13 fixed to the pivot bearing 8 of the wiper pivot 6, and a support shaft 15 supported on the main arm 2, specifically, a support shaft 15 on the lower surface of the arm head 3.
The fixed gear 13 is rotatably supported by the fixed gear 13.
The driven gear 14 meshes with the driven gear 14. The actuating rod 12 has one end rotatably connected to a pin 16 protruding from the lower surface of the rear end of the sub-arm 4, and the other end is located at a position offset from the rotation center of the driven gear 14, for example in this embodiment. Here, it is rotatably connected to a pin 18 that projects from the lower surface of a protrusion 17 that is integrally molded on the lower surface of the driven gear 14.

Note that 19 in FIGS. 1 and 2 indicates that the seal member 20 is a vehicle body panel.

According to the above embodiment structure, wiper arm 1
When the wiper pivot 6 swings, the driven gear 14 of the gear mechanism 11 rolls on the tooth surface of the fixed gear 13. On the other hand, the actuating rod 12 is connected to the driven gear 1.
Since it is connected at a position offset from the center of rotation of the driven gear 14, it moves linearly as the driven gear 14 rotates, thereby moving the sub-arm 4 forward and backward.

Here, the connection point of the actuating rod 12 with the driven gear 14, that is, the position of the pin 18, moves on the circumference around the rotation center 15 of the driven gear 14 due to the rotation of the driven gear 14, as shown in FIG. do. Therefore, the forward and backward stroke amount L of the sub-arm 4 is defined as the rotation locus diameter l of the connection point 18.
The maximum amount of lateral overhang of the wiper arm 1 is obtained as half of that amount, l/2. As a result, the maximum amount of lateral protrusion of the connecting point 18 of the wiper arm 1 can be made smaller than that of the conventional two-bar link type, and the straight line connecting the center of the pivot 6 and the connecting point 16 can be The angle formed by the straight line connecting the point 18 and the connecting point 16 can be made smaller, thereby reducing the component force acting on the main arm 2 from the sub arm 4 in the pressing direction, and reducing the sliding resistance between the two. This allows the sub-arm 4 to move forward and backward smoothly.

Next, the wiper device having the structure of this embodiment will be described as a so-called single arm type wiper in which a single wiper arm 1 is swung approximately 180 degrees within the plane of the windshield G to wipe the wiper, as shown in FIGS. 4 and 5, for example. The effect will be explained in detail when applied to a device.

Here, the driven gear 14 is the wiper arm 1.
It is assumed that the fixed gear 13 makes two rotations on the tooth surface for a 180° swing.

In a general wiper device in which the wiper arm does not extend or contract, the wiping area _A1 of the windshield G is obtained by the circular motion trajectory of the wiper blades W and B around the wiper pivot 6, as shown by the chain line in FIG.

On the other hand, in the device of this embodiment, as shown in FIG. 5, when the wiper arm 1 moves forward from the stop position, the driven gear 14 rotates on the tooth surface of the fixed gear 13. moves on a circular orbit centered on the rotation center of the driven gear 14, pushes the actuation rod 12, and causes the sub-arm 4 to move forward. When the wiper arm 1 swings 45 degrees, the connecting point 18 moves 180 degrees, and the sub arm 4
will be expanded to the maximum. When the wiper arm 1 further swings, the sub-arm 4 begins to retreat due to the movement of the connection point 18, and returns to the original maximum retreat position at the position where the wiper arm 1 is swung 90°. The above behavior is repeated again by swinging the wiper arm 1 between 90° and 180°. The broken line a in FIG. 5 is the connection point 1 on the sub-arm 4 side of the actuation rod 12
6, and this movement trajectory is the movement trajectory of the wiper blades W and B. Therefore, as shown by the solid line in FIG. 4, the movement locus of wiper blades W and B is
Due to the 180° swing of the window glass G, a bulge is created at both upper corner portions of the windshield G, and the wiping area can be greatly expanded from _A1 to _A2 . In addition, in the case of a so-called double arm type wiper unit in which a pair of wiper units are operated synchronously, the wiping area can be expanded by moving the sub-arm back and forth a plurality of times during the forward or backward movement of the wiper arm.

In the embodiment shown in FIGS. 6 and 7, a guide arm 2a is provided protruding from the front end of the main arm 2, and a sub-arm 4 is formed into a cylindrical shape and is slidably fitted into the guide arm 2a. , the operating mode is exactly the same as in the previous embodiment. However, in this embodiment, since the sub-arm 4 can be reinforced from the inside by the guide arm 2a, a resin molded body can be used as the sub-arm 4, which improves the sliding properties of the sub-arm 4. It has the advantage of being lightweight.

Effects of the Invention As described above, according to the present invention, the sub-arm can be moved forward and backward multiple times during the forward or backward movement of the wiper arm with a simple structure, and the wiping area can be expanded, and the sub-arm can move forward and backward. The wiper blade can operate smoothly and the wiping performance of the wiper blade can be further improved, and
The drive mechanism of the sub-arm does not protrude significantly to the side of the wiper arm, improving the appearance and making the installation layout on the vehicle body easier.
This has the great effect of greatly improving the operability of attaching and detaching the wiper device.

To explain how to improve the workability of attaching and detaching, when removing the wiper device from the vehicle body to replace parts, etc., leave the wiper pivot 6, pivot bearing 8, and fixed gear 13 on the vehicle body, and remove the other parts.
That is, the arm head 3, main arm 2, sub arm 4, operating rod 12, and driven gear 14 can be removed from the vehicle body while remaining as an integrated unit, and the arm head 3 can be removed from the wiper pivot 6.
At the same time, the driven gear 14 can also be removed.

Furthermore, when the wiper device is attached to the vehicle body during the production process, there are only two attachment points: the attachment between the arm head 3 and the wiper pivot 6, and the engagement between the driven gear 14 and the fixed gear 13. The workability of attaching and detaching to the vehicle body is greatly improved.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the main parts of an embodiment of the present invention, FIG. 2 is a sectional view taken along the - line in FIG. An explanatory diagram of the operation when the embodiment device is applied to a single arm type wiper device, FIG. 5 is an explanatory diagram of the operation mode of the same drive mechanism, FIG. 6 is a sectional view showing a different example of the present invention, and FIG. FIG. 7 is a sectional view taken along the - line in FIG. 6; 1... Wiper arm, 2... Main arm,
4...Sub arm, 6...Wiper pivot, 8
... Pivot bearing, 10 ... Sub-arm drive mechanism, 11 ... Gear mechanism, 12 ... Operating rod, 1
3... Fixed gear, 14... Driven gear.

Claims (1)

[Scope of Claims] 1. A wiper arm consisting of an arm head fixed to a wiper pivot, a main arm pivotally supported by the arm head, and a sub-arm fitted to the main arm so as to be able to move forward and backward, and a fixation provided on the pivot bearing. A sub-arm drive mechanism consisting of a gear mechanism consisting of a gear and a driven gear that meshes with the fixed gear, and an actuating rod that has one end connected to the sub-arm and the other end connected at a position offset from the rotation center of the driven gear in the driven gear. An automobile wiper device comprising the following: The driven gear is pivotally supported by the arm head.