JPS59219533A - Brake shoe for bicycle - Google Patents

Abstract

PURPOSE:To reliably improve the braking function as a whole by providing several cut lines on a shoe proper in the direction at a right angle to the length direction along the rim proceeding direction and to a predetermined depth from the braking surface against the rim. CONSTITUTION:A brake shoe is constituted by fitting a holder 2 supporting a shoe proper 1 to a pair of arms A of a caliper brake respectively, and the braking surface 3 of the shoe proper 1 is squeezed to both sides of a rim R of a wheel by pulling an operating wire W provided on the upper end of the arm A. A proper number of cut lins 5 are provided on the shoe proper in the direction at a right angle to the length direction along the preceeding direction of the rim R and to a predetermined depth from the braking surface 3 against the rim R to form a proper number of shoe pieces 11-16. Thereby, individual shoe pieces 11-16 are flexed during braking, and a large edge braking function can be attained as a whole.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bicycle brake shoe, and more particularly to a bicycle brake shoe having a shoe body that presses against the rim of a wheel.

Conventionally, this type of brake shoe has a shoe body that is formed into a solid bar shape as a whole, and has a braking surface that presses against the rim over a predetermined length in the direction of movement of the shoe.
During braking, by pressing the braking surface of the shoe main body against the rim, the entire surface of the braking surface performs a surface braking function, and the rear end of the braking surface in the direction of movement of the rim bites into the rim. The edge braking function is used to brake the rotation of the wheels.

However, during braking, it is difficult for the shoe main body to press the entire braking surface against the rim evenly, and a large uneven load is applied only to one side of the braking surface. Not only is it not possible to obtain a predetermined surface braking function of a size commensurate with the area, but also as for the edge braking function, there is only one place that performs the function, so it is difficult to make the entire braking function large enough. There was a problem that I couldn't do it.

Therefore, it has been proposed that the braking surface of the shoe main body is provided with a plurality of protrusions having a constant height with respect to the braking surface at predetermined intervals.

However, when a plurality of protrusions are provided as described above, although the number of protrusions that exert the edge braking function can be increased, since the protrusions are formed so as to be in contact with the rim, the surface braking function is reduced accordingly. In addition, it is easy for water to enter the groove between the protrusions, and the water that has entered is likely to be supplied between the braking surface on the surface of the protrusion and the rim, reducing the braking function, which is the root cause of the above-mentioned problem. It cannot actually be solved.

The purpose of the present invention is to increase both the surface braking function and the edge braking function without increasing the external dimensions of the braking surface in the main body of the shoe, and also to suppress the deterioration of the braking function due to water, thereby ensuring the overall braking function. The object of the present invention is to provide a bicycle brake shoe that is improved in terms of performance.

The structure of the present invention is that in a bicycle brake shoe having a shoe body that presses against the rim of a wheel, the shoe body is provided with a brake shoe in a direction orthogonal to a longitudinal direction along the traveling direction of the rim, and a brake shoe on the rim. Hereinafter, embodiments of the brake shoe of the present invention will be described with reference to the drawings.

The one shown in the drawing is applied to a cantilever brake for a bicycle. ) and is attached to each tip of a pair of arms (A), (A) in a caliper brake, the cylindrical holder having a quadrilateral peripheral wall (21), wherein the shoe body (1) is , is made of a rubber material and has a trapezoidal cross-sectional shape with two stages, one half of which is supported by the peripheral wall (21) of the holder (2) in a hugging manner, and the other half is supported by the peripheral wall (21) of the holder (2). A braking surface (6) that presses against the rim (R) over a predetermined length in the traveling direction of the rim (R) is formed on the exposed end surface of the rim (R). Then, the holder (2) supporting the shoe main body (1) is attached to the arms (A), (A) respectively by the attachment means (4), and the holder (2) supporting the shoe body (1) is attached to the upper end of the arms (A), (A). By pulling the provided operating wire (W), the braking surfaces (3), (6) of the shoe bodies (1), (1) are clamped against both sides of the rim (R). It is operated by pressure contact.

Therefore, the present invention basically provides the above-mentioned shoe body (1
), a braking surface (6) with respect to the rim (R) in a black direction perpendicular to the length direction along the traveling direction of the rim (R).
at least one cut (5) extending to a predetermined depth from
It has been established.

What is shown in FIG. 1 and FIG. 3(a) is that the rim (R) is located in the vicinity of the central portion of the shoe main body (1) in the longitudinal direction along the traveling direction. In the direction
In addition, five cuts (5) are provided at a predetermined depth in a direction orthogonal to the braking surface (6) on the rim (R), with a width of zero, so that the braking surface (6) on the shoe body (1) )
On the side, shoe pieces (11), (12) with a large thickness in the longitudinal direction are formed on both sides in the longitudinal direction, and a shoe piece (13) with a small thickness in the longitudinal direction is formed in the middle part.
(14), (15), and (16) were formed.

Therefore, in the above configuration, the shoe main body (1)
When braking is performed by pressing the braking surface (6) of the rim (R) against the side surface of the rim (R), each of the shoe pieces (11) to (16) flexures as shown in FIG. When the rear end in the direction of travel bites into the rim (R), it activates and exerts a large edge braking function on the whole, and the surface braking function does not deteriorate, and the whole brake has a large braking function. ◎ And the above throat (each of the shoe pieces (11) to (16)
) is bent and actuated, each shoe piece (11) to (
Although gaps (6) with a triangular cross section are formed between the braking surface (3) of 16) and the rim (R), these gaps (6) are extremely small, and these gaps ( 6
)... Since the gap (5) leading to the gap is zero and is in a closed state, it is difficult for water to enter into each gap (6)...- even during rain, and as a result, the braking surface (6) This makes it difficult for water to be supplied between the rim (R) and the rim (R). This solves the problem of water droplets being supplied and prevents deterioration of braking function due to water intrusion.

Moreover, between each of the shoe pieces (11) to (16), the rim (
The shoe piece (12) on the front side in the direction of movement of R) has a large thickness in the longitudinal direction, so it has high deflection resistance and prevents the other shoe pieces (13) to (16), which are smaller in thickness, from bending too much. As a result, the above-mentioned gap (6) is always stably maintained in a small state, and a large braking function is stably maintained even during rain. It can be secured.

By the way, there are two types: those with cuts (5) as shown in Figures 1, 3 (-), and 4, and the conventional one shown in Figure 6 (-).
, +) with no break (5) at all, and the 6th
As shown in Figure (k), the braking function was compared with the one provided with a large groove that communicates with the braking surface (6) even during braking through the following experiment. The experimental conditions for this experiment were to attach the shoe to the rim (R) of the rear wheel, drive the shoe at a constant speed on a predetermined paved road in a wet state where the rim (R) and the shoe body (1) are exposed to water; Brake control lever (not shown)
We decided to operate the bicycle until it touched the handlebar and measure the braking distance of 1lJlx from the time of operation.

According to this experiment, the braking distance .0, whereas in the embodiment shown in FIG. 6 (IL), it was 243, which means that the braking distance could be reduced by about 25%.

In addition, under the above experimental conditions, experiments were conducted in the same manner with various forms of the cut (5), and the braking distances X were measured for each, and the values shown in Table 1 were obtained. .

In this Table 1, the values of the example shown in FIG. 6(a) described above are also listed.

In other words, the throat (width of cut (5) (B) in Figure 3 (IL)
) is zero, and when three are provided near the longitudinal center of the braking surface (3), the value of X becomes 24.3, and as shown in FIG. 5) Eye width (B
) is set to the maximum value B1 so that it becomes zero at the position of the braking surface (6) during braking, and the braking surface (3) is divided into three equal parts in the entire length direction. The value of X is 24.3, and the width of the cut (5) (
E) is 1/2 times the maximum value B, and the braking surface (6) is placed at a position where the braking surface (6) is equally divided in the entire length direction, as shown in Fig. 3 (Q). (d) and Fig. 3(e) Throat (1 tree, 2 trees, and 6 throats, respectively), the value of X was 241.24.4.24.9. The width (B) of the cut (5) has a value of n,
As shown in FIG. 6(f), the rim (
R) with only one on the rear side in the direction of travel, and the sixth
In the case where only one piece is provided on the front side in the direction of movement of the rim (R) as shown in Figure (g), the values of X are 24.9 and 27.3, respectively, and the cut (5 )
The width (B) of the braking surface (3) is the value of the number, and the shape that protrudes toward the rear in the direction of travel of the rim (R) in Fig. 3 (h) is the length direction of the braking surface (3). In the case where only one wire was provided at the center position, the value of X was 24.7.

Judging from the above experimental results, the shoe body (1)
1) The width (B) is not limited to only zero, but has a width that closes only at the position of the braking surface (3) when braking from zero, that is, between the maximum value B1 By doing so, the braking surface (
3) and the rim (R) are closed by each cut (5), so a large braking function is obtained.

2) Regarding the number and installation position, select a value of 1 to 5, and in order to prevent the shoe pieces from bending too much, for example, as shown in Figure 3 (a), set the shoe pieces on the front side in the direction of movement of the rim (R). By making the shoe piece (11) thicker, a greater braking function can be obtained.

3) Also, the shape in the width direction should be straight or the rim (R)
It is preferable that the shape protrudes rearward in the direction of travel.

Table 1 4) Also, in Table 1, the braking surface (6) of the cut (5)
Although the installation direction in the thickness direction is shown only in the direction orthogonal to the braking surface (3), as shown in FIG.
When the side is inclined toward the front side in the direction of movement of the rim (R), the value of the braking distance X becomes, for example, 22, and a large braking function is obtained.

Although the above explanation is applied to a cantilever type 1 brake, it goes without saying that the invention can also be applied to caliper brakes and rim brakes.

As described above, the present invention provides a shoe main body that is in pressure contact with the rim of a bicycle wheel, in a direction perpendicular to the length direction along the traveling direction of the rim, and over a predetermined depth from the braking surface with respect to the rim. Since at least one cut is provided, the edge braking function can be exerted at multiple locations without increasing the external dimensions of the braking surface in the shoe body.
A large edge braking function is thickened throughout (it is possible to do so,
Moreover, when braking, a gap is created between the braking surface and the rim, but this gap is extremely small, and the cuts leading to these gaps are closed, so there is a gap between the braking surface and the rim during rain. 3) Intrusion of water is suppressed, preventing deterioration of the braking function due to water intrusion, and achieving greater braking function.Furthermore, since only a cut is provided on the braking surface, the surface side action function is improved. It is also possible to suppress the deterioration of the brake system, and compared to conventional brake systems, a sufficiently large braking function can be exerted stably even during rainy weather.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective explanatory diagram showing an embodiment of the present invention;
Figure 2 is an explanatory diagram showing the state in which it is assembled into a bicycle cantilever type 1 brake, Figure 6 (a) is a plan view, Figure 3 (l
6(j) and 6(k) are explanatory diagrams of the conventional method. (R)... Wheel rim (1)... Shoe body (6)... Braking surface (5)... Cut agent Patent attorney Tsu 1) Naohisa -x-, +1'j, ,
.

Claims (1)

[Claims] In a bicycle brake shoe having a shoe body that presses against the rim of a wheel, the shoe body is provided with a predetermined depth from the braking surface with respect to the rim in a direction orthogonal to the length direction along the traveling direction of the rim. At least 1
A bicycle brake shoe featuring a book-like cut.