JP2004136774A - Wiper blade rubber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wiper blade rubber effective in suppression or elimination of a chattering noise and reversing noise. <P>SOLUTION: The wiper blade rubber comprises a support part 2 supported in a nipped state at the mounting part of a wiper arm; and a lip part 6 formed extending from the support part through a neck part 5 and approximately in a triangular shape in a section and having the vertex part of a point brought into slide contact with a surface to be wiped. Further, a slit 9 promoting inclination deformation of the lip part by spreading toward a moving direction when the vortex part of the lip part is slid along the surface to be wiped is formed in the slide of the lip part. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an improved wiper blade rubber, and more particularly to a wiper blade rubber structure that is effective in suppressing chattering noise (stick slip) generated during a wiping operation.
[0002]
[Prior art]
In recent vehicles, the front window is formed by a complex curved surface having slightly different curvatures in the vertical and horizontal directions, and the wiper blade is also provided with an angle for mounting so as to correspond to this, so that a smooth wiping operation can be obtained. Ingenuity is devised. However, on the other hand, a water repellent is often applied to the glass surface in order to suppress fogging and adhesion of dirt on the glass surface. For this reason, even with a properly mounted wiper, the sliding friction resistance at the wiping portion of the wiper blade rubber may change due to the water repellent, causing chattering during the wiping operation.
[0003]
Techniques for suppressing or eliminating the chattering noise of the wiper blade include improving the physical properties of the wiper blade rubber, particularly the physical properties of the tip of the lip portion in sliding contact with the glass surface, and improving the cross-sectional shape of the wiper blade rubber. It is roughly divided into.
As an example of the former, there is one in which at least a cutting edge portion is covered with a surface coating layer made of a predetermined thermoplastic elastomer composition (for example, see Patent Document 1).
Further, as an example of the latter, the wiper blade rubber has an asymmetric cross-sectional shape such that the difference in contact angle between the lowering and the raising operation of the wiper blade is twice the error angle, and the wiper blade rubber and glass in the reciprocating operation. There is one in which the angle with the surface is equal (for example, see Patent Document 2).
[0004]
[Patent Document 1]
JP 2001-151087 A (Claims)
[Patent Document 2]
Japanese Utility Model Application Laid-Open No. 59-116254 (claims for registration of utility model and specification, page 5 lines 7 to 11, FIG. 5)
[0005]
[Problems to be solved by the invention]
However, when the cutting edge portion is coated with a special material as disclosed in Patent Document 1, not only the cost is increased but also the coating layer may peel or wear due to repetition of sliding, and the desired effect may not be achieved. There is.
[0006]
In addition, the technique disclosed in Patent Document 2 has an asymmetric structure, as shown in FIG. 5 of the document, in which a left-right gap (a neck portion) formed between the bottom surface of the blade main body of the wiper blade rubber and the upper surface of the triangular portion. This is achieved by forming one so that one side is wide and the other is narrow. For this reason, the inclination angle between the triangular portion of the wiper blade rubber and the glass surface in the reciprocating operation can be made as equal as possible, and chattering noise generated when the triangular portion becomes slightly standing can be suppressed.
[0007]
However, in this technique, since one gap is formed wider than usual, the wiper blade rubber is inverted at the top dead center or the bottom dead center during the reciprocating operation of the wiper blade, and the upper surface angle of the triangular portion is reduced. When colliding with the bottom of the main body, the reverse sound tends to be loud.
[0008]
SUMMARY OF THE INVENTION An object of the present invention is to provide a wiper blade rubber which is relatively low cost and is effective for suppressing or eliminating chattering sound and inversion sound.
[0009]
[Means for achieving the object]
The present invention has the following configuration to achieve the above object.
That is, the wiper blade rubber is formed in a substantially triangular cross section through a support portion sandwiched by the mounting portion of the wiper arm and a neck portion from the support portion, and the top of the tip is slidably contacted with the surface to be wiped. A lip portion. Further, a slit is formed on a side surface of the lip portion, which expands in the moving direction when the tip portion of the lip portion is slid along the surface to be wiped, and helps the lip portion to be inclined and deformed. There is a feature in the point.
[0010]
The slit is formed on one side or both sides of the neck portion so as to match an operation process in which a chattering noise is generated in the reciprocating motion of the wiper blade. Usually, the reciprocating wiper blade is formed on the side surface of the lip portion where the wiping surface in the going process from the bottom dead center to the top dead center is located on the side.
[0011]
The position, length, or width of the slit is not particularly limited as long as it expands in the moving direction and promotes the lip to be inclined and deformed, and the strength and elasticity of the wiper blade rubber are not particularly limited. Depending on the physical properties such as the above, it is appropriately set within a range in which stress concentration hardly occurs.
The slits may be formed in a plurality of steps on the side surface of the lip.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail based on illustrated embodiments.
FIG. 1 is a sectional view of a wiper blade rubber according to one embodiment of the present invention.
The wiper blade rubber 1 has a support portion 2 at an upper portion thereof, which is sandwiched by a mounting portion of a wiper arm (not shown). The supporting portion has two upper and lower grooves 3 and 4 on the side surface, a packing plate (not shown) is similarly fitted in the upper groove 3, and the lower groove 4 has a substantially C-shaped mounting portion. The lower ends of both sides are locked.
A lip portion 6 is connected to a lower portion of the support portion 2 via a neck portion 5.
[0013]
Such a structure is not different from the cross-sectional structure of the conventional wiper blade rubber. FIG. 3 shows a sectional view of a conventional wiper blade rubber 11. Regarding each part of the conventional example, each part corresponding to the wiper blade rubber of FIG. 1 according to the present invention is denoted by the same reference numeral in the tenth. The lip portion is indicated by reference numeral 16 but has a different structure from the lip portion 6 according to the present invention as described below.
[0014]
The lip portion 6 of the wiper blade rubber 1 according to the present invention is formed to have a substantially triangular cross section, and includes a shoulder portion 7 extending left and right at the upper part in the drawing. The shoulder portion 7 of the lip portion 6 facing the stopper surface 2a, which is the bottom surface of the support portion 2, is formed slightly narrower than the stopper surface 2a. Reference numeral 8 in the drawing is a gap formed between the upper surface of the shoulder portion and the stopper surface 2a, and has the same width on both the left and right sides. The gap 8 naturally corresponds approximately to the height of the neck 5.
[0015]
The lip portion 6 has one slit 9 formed on one side surface along the longitudinal direction. The slit 9 promotes the lip portion 6 to be inclined and deformed by expanding when the one side surface of the lip portion 6 is applied to the lower end of the lip portion by the action force caused by sliding. On the other hand, when the above-described acting force is applied to the lower end of the lip portion on the other side surface of the lip portion, the lip portion 6 is simply closed without being promoted by maintaining the closed state and promoting the inclination deformation.
In addition, reference numeral 6a is a wiping portion at the tip of the lip portion which comes into contact with the glass surface.
[0016]
Before describing the operation of the present wiper blade rubber, the operation of the conventional wiper blade rubber will be described with reference to FIG.
FIG. 4 is a diagram illustrating a forward path step (upward operation step) from bottom dead center to top dead center and a return path step (downward operation step) from top dead center to bottom dead point after inversion at positions 2A to 2H in the drawing. FIG. 2 shows a cross-sectional view of the wiper blade rubber 11.
At each position from 2A to 2C, the wiper blade rubber 11 slides with its lip inclined at an angle of θ2a to θ2c with respect to the curved surface of the windshield.
[0017]
In general, it is said that an ideal inclination angle θ (an inclination angle suitable for performing a smooth wiping action without generating chattering noise) at which the lip portion falls with respect to the glass surface is 30 degrees to 50 degrees. I have. θ2a to θ2c form angles of approximately 40 degrees, 42 degrees, and 50 degrees because the wiper blade is attached at an angle to the glass surface, and are within the range of this ideal inclination angle. . However, at the 2D position, the curvature of the glass surface is extremely different from the curvature of the process range up to that point, and the glass surface is curved so that the back of the paper in the drawing is recessed. For this reason, the tip of the lip part rises up, for example, the inclination angle θ2d becomes about 55 degrees, and a chattering sound is generated. In the figure, a thin shadow portion (region X) indicates a portion where the curvature changes extremely.
[0018]
On the other hand, the wiper that has reached the top dead center has the cross-sectional state shown by 2E when the wiper blade rubber 11 is inverted. In this state, on the contrary, the inclination angle θ2e is about 30 degrees, and the proper inclination angle is maintained. Then, in the return path toward the bottom dead center, the inclination angles (θ2f to θ2h) maintain appropriate angles (35 degrees, 42 degrees, and 45 degrees) from 2F to 2H.
[0019]
Next, the operation of the wiper blade rubber 1 according to the above embodiment will be described with reference to FIG.
Since the wiper blade rubber 1 in the forward path has the slit 9 formed on the side surface of the moving direction, the inclination angle θ becomes smaller than that of the conventional example in FIG. Indentation becomes larger). At the positions 1A to 1C, the inclination angles (θ1a to θ1c) are approximately 33 degrees, 35 degrees, and 43 degrees, respectively, and are within the above-described range of the appropriate inclination angles.
At the top dead center (1D position), the inclination angle θ1d is smaller than that of the conventional example and is about 48 degrees due to the expanding action of the slit 9. The inclination angle θ1d is within the range of the appropriate inclination angle, the rise of the lip portion is suppressed, and the occurrence of chattering noise is suppressed.
[0020]
The lip portions at the positions 1E to 1H after the reversal at the top dead center perform the same sliding action as the above-described conventional example because the slit 9 is closed. As a result, the inclination angles (θ1e to θ1h) at each position are not different from those of the conventional example (θ2e to θ2h), and the proper inclination angles are maintained.
[0021]
Therefore, the wiper blade rubber 1 according to the present invention minimizes the generation of chattering noise at a location near the top dead center of the outward path.
Further, since the gap between the shoulder 6 and the stopper 2a is formed to the same extent as that of the conventional example, a large inversion sound does not occur as in the above-described prior art.
[0022]
The slit needs to be located on the front side in the moving direction of the wiper in the outward path process. However, for example, when the wiper arm is deformed for some reason and chattering sound is generated due to the rising of the lip portion in the return path, the slit is expanded in the return path (1E to 1H in FIG. 2). The wiper blade rubber may be mounted in a direction opposite to the above embodiment.
Further, the slits may be formed on both side surfaces of the lip portion so as not to interfere with each other, or may be arranged in multiple stages on one side surface.
[0023]
【The invention's effect】
According to the present invention, the following effects can be obtained.
Slits that can be expanded in the direction of movement are formed on the sides of the lip, so the inclination of the lip can be further promoted in the direction in which the lip falls down compared to conventional types without slits, and the curvature is tight. The rising of the glass surface during the wiping operation is also prevented, and the generation of chattering noise can be suppressed.
[0024]
Further, the gap around the neck portion is not different from the conventional one, so that it is possible to suppress the generation of chattering sound without increasing the reverse sound.
[Brief description of the drawings]
FIG. 1 is a sectional view of a wiper blade rubber according to one embodiment of the present invention.
FIG. 2 is an explanatory view showing the operation of the wiper blade rubber of FIG. 1;
FIG. 3 is a cross-sectional view of a wiper blade rubber according to a conventional example.
FIG. 4 is an explanatory view showing the operation of the wiper blade rubber according to the conventional example of FIG. 3;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Wiper blade rubber 2,12 Support part 3,13 Upper groove 4,14 Lower groove 5,15 Neck part 6,16 Lip part 7,17 Shoulder part 8,18 Gap 9 Slit 11 Conventional wiper blade rubber

Claims (3)

A wiper blade including a support portion sandwiched between the mounting portions of the wiper arm, and a lip portion formed in a substantially triangular cross-section from the support portion via a neck portion, and a top portion of the tip slidingly contacting the surface to be wiped. In rubber,
On the side surface of the lip portion, a slit is formed to promote the lip portion to be inclined and deformed by expanding in the moving direction when the tip portion of the lip portion is slid along the surface to be wiped,
A wiper blade rubber, characterized in that: The slit is formed on the side of the lip portion where the wiping surface in the going process in which the reciprocating wiper blade moves from the bottom dead center to the top dead center is located aside.
The wiper blade rubber according to claim 1. The slit is formed in a plurality of steps on the side surface of the lip portion,
The wiper blade rubber according to claim 1 or 2.

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