JPH0580989U - Bicycle brake - Google Patents

Abstract

(57) [Abstract] [Purpose] A swingable arm (1), brake shoes (14),
Furthermore, the pulling wire (18) is provided with the pulling wire (18).
The rocking lever (1) to rock the brake shoe (14).
In a bicycle brake in which the wheel is pressed against the peripheral side surface of the wheel rim, the braking efficiency of the brake should be improved so that the brake can easily work even with a small operating force. [Structure] An imaginary straight line that is orthogonal to a line connecting the connecting portion of the pulling wire (18) to the arm (1) and the swing fulcrum of the arm (1) and extends from the attaching portion of the pulling wire (18). A cable guide (G) that abuts from above is provided on the cable, and the pulling wire (18) is pulled while the cable guide (G) is in contact with the pulling wire (18) from above.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a bicycle brake such as a cantilever type caliper brake, and more particularly to a bicycle brake with improved braking efficiency.

[0002]

[Prior Art and Problems]

 There is a cantilever type caliper brake as a type of brake used for braking a bicycle, which is configured as shown in FIG. The tip of the brake cable (16) is attached to the upper part of the cable fixing device (15), and the lower part of the cable fixing device (15) has a pulling wire () for swinging a swingable arm (1) described later. The central part of 18) is hooked.

Both ends of the pulling wire (18) are connected to the upper ends of the arms (1) (1) swingably attached to the seat stays (T) (T). The arms (1) and (1) are swingably fixed to the seat stays (T) and (T) at the swing fulcrums (11) and (11) at the lower end. ) (1) The brake shoes (14) (14) that press the wheel rim (R) are installed in the middle.

In this brake, first, when the brake lever is gripped, the brake cable (16) and the pulling wire (18) connected to the brake cable (16) are pulled up, and the arm (1) connected to this is connected to the lower end of the arm. Swing to the rim (R) side around the swing fulcrum (11). Then, the wheel is braked by the frictional force (hereinafter referred to as a braking frictional force) acting between the brake shoe (14) attached to the arm (1) and the rim (R).

This cantilever type caliper brake has an advantage that the brake body is small and lightweight. However, the above conventional brake has a problem that the braking efficiency of the brake is poor. This problem will be described in more detail.

The above problem is caused by the following two causes. First, the first cause will be described. As shown in FIG. 10, when the straight line (10) connecting the connecting portion of the pulling wire (18) in the arm (1) and the swing fulcrum (11) of the arm (1) is considered, the straight line (10) As the angle (S1) formed by the pulling wire (18) becomes smaller, the pulling wire (18) and the arm (1) come closer to being aligned with each other.

Then, when the straight line (10) and the pulling wire (18) approach a straight line and the angle (S1) becomes extremely small, the tension of the pulling wire (18) becomes a force for swinging the arm (1). Almost no conversion. Next, the second cause will be described. As shown in FIG. 10, in the above-mentioned conventional one, the angle (S1) formed by the straight line (10) and the pulling wire (18) is not 90 degrees.

Therefore, the swinging direction of the arm (1) and the tension direction of the pulling wire (18) acting on one end of the arm (1) do not match, and the pulling wire (18) moves from the pulling wire (18) to the arm (1). The force (P) acting on the upper end of the arm is not completely converted to the force (F) for swinging the arm (1). From this, in the above-mentioned conventional one, the arm (1) cannot be efficiently swung on the basis of the above two causes, and the brake shoe (14) provided on the arm (1) does not move to the rim ( The pressing force (C) acting on the side surface of (R) and the braking frictional force proportional to the magnitude of the pressing force (C) are not sufficiently generated, and the braking effect is deteriorated.

In view of such a point, the present invention provides "a swingable arm (1) disposed on a side of a wheel rim of a stay for supporting a wheel of a bicycle, and an arm attached to the arm (1). A brake shoe (14) and a pulling wire (18) for pulling the arm (1) to swing the arm (1), and swinging the arm (1) with the pulling wire (18). In the case of a bicycle brake in which the above-mentioned brake shoes (14) are pressed against the peripheral side surface of the rim of the wheel, the braking efficiency of the brake is improved and the brake force is reduced even with a small operating force. The task is to make it effective.

[0010]

[Technical means]

 The technical means of the present invention for solving the above-mentioned problem is to dispose a cable guide (G) such as a guide roller at a portion deviated from the swing end of the arm (1) to the pulling wire (18) side. In addition to installing the cable guide (G), the pull wire (18) is extended in such a way that the distal end of the pull wire (18) is connected to the attachment portion (100) of the arm (1), and the attachment portion (100) and The pull wire (18) connecting the cable guide (G) to the arm (1) is perpendicular to the straight line (10) connecting the swing fulcrum of the arm (1). " ..

[0011]

[Action]

 The above technical means act as follows. When the brake lever is gripped like the conventional one, the pull wire (18) is pulled up.The pull wire (18) extends to the arm (1) side via the cable guide (G). There is.

Therefore, when focusing on the pulling wire (18) in the area from the cable guide (G) to the arm (1), the upper end position of the area (contact point with the cable guide (G)) is stable. Therefore, the upper end position does not move upward with the pulling of the pulling wire (18). Therefore, when the pulling wire (18) is pulled, the upper end of the pulling wire (18) rises, as in the conventional one described above, and the swing fulcrum of the arm (1) and the attaching portion (100) of the pulling wire (18). The angle of the pulling wire (18) with respect to the straight line (10) connecting () and (), which is a right angle in the present invention, rarely decreases.

Further, when the pull wire (18) is pulled by grasping the brake lever, the arm (1) is swung by the pulling force of the pull wire (18). Then, the rotational moment which is the vector product of the distance from the attachment portion (100) of the pulling wire (18) to the arm (1) to the swing fulcrum of the arm (1) and the pulling force of the pulling wire (18). The action causes the arm (1) to swing.

The swing of the arm (1) causes the brake shoe (14) to come into contact with the peripheral side surface of the rim and press it against that portion, and the friction force between the two is proportional to the magnitude of this pressing force. Brakes the wheels. At this time, since the pulling wire (18) extends in a direction orthogonal to the straight line connecting the attaching portion (100) of the pulling wire (18) to the arm (1) and the swing fulcrum of the arm (1), The swing direction of the arm (1) and the pulling direction of the pulling wire (18) will coincide.

Therefore, the pulling force acts as a force for swinging the arm (1) with the same magnitude, whereby the brake shoe (14) attached to the arm (1) acts on the rim. Since the pressing force applied to the side surface is also maximum, the braking friction force proportional to the size of the pressing force is also maximum.

[0016]

【effect】

 Since the braking friction force is maximized, the braking efficiency is improved and the braking effect is improved even with a small operating force.

[0017]

【Example】

 Next, the embodiment of the present invention described above will be described in detail with reference to the drawings. FIG. 1 shows a state in which the present invention is applied to a rear wheel, and in this embodiment, a horseshoe-shaped arch (20) for keeping a distance between seat stays (T) (T) is provided. The present invention is applied to a bicycle.

At the seat stays (T) (T) facing each other with the tire portion (Y) of the wheel interposed therebetween, the arms (1) and (1) swing together with the arch (20) with bolts (28) and (28). In addition to being movably fixed, an outer tube (17) is fixed to the upper part of the arch (20), and further, on the back surface of the arch (20), as shown in FIGS. 1 and 4. A roller (19) as a cable guide (G) is rotatably supported by a shaft (19a).

A cable connector (15) is attached to the tip of the brake cable (16) pulled out from the outer tube (17), and the lower end of the cable connector (15) is shown in FIG. As shown, it is bent upward to form a locking portion (15a). Then, the central portion of the pulling wire (18) is hooked on the cable connector (15).

The tip of the pulling wire (18) is fixed to the swing end of the arm (1) (1) through the bottom of the roller (19) arranged on the back surface of the arch (20) and , When considering a straight line (10) connecting the above-mentioned bolt (28) which becomes the swinging fulcrum (11) of the arm (1) and the attachment portion (100) of the pulling wire (18), the straight line (10) Is set so that the above-mentioned pulling wires (18) are orthogonal to each other.

A brake shoe (14) is attached to the middle of the arm (1), and the brake shoe (14) and the pulling wire (18) are attached in a specific structure. It is as shown in FIG. 3 and FIG. First, as shown in FIG. 5, a bolt (5) is inserted near the swing end of the arm (1), and the shaft of the bolt (5) is positioned near its head. A through hole (57) is drilled.

The tip of the pulling wire (18) is inserted through the through hole (57), and the tightening nut (55) is screwed into the threaded end of the bolt (5). .. Further, as shown in FIGS. 3 and 5, a bolt (6) for mounting the brake shoe (14) is inserted in the middle of the arm (1), and the head of the bolt (6) is inserted. The support shaft (141) of the brake shoe (14) is inserted into the through hole (67) formed in the (60).

Then, a nut (65) is screwed and fastened to the threaded end portion of the bolt (6), thereby fixing the brake shoe (14) on the arm (1). Further, as shown in FIGS. 5 and 6, the base end portion of the arm (1) is attached to the cylindrical body (T1) welded to the side wall of the seat stay (T) by an arch (a bolt (28) and a nut (41)). It is fixed in a state of being overlapped with 20).

In this case, since the roller (19) is in contact with the pulling wire (18) from above, even if the pulling wire (18) is pulled up during braking, even if the pulling wire (18) is pulled up, that is, the above-mentioned roller. The part from the (19) to the connecting part of the arm (1) hardly moves upward. Next, in this product, the bolt (28) part (hereinafter referred to as the swing fulcrum (11)) for attaching the arm (1) to the seat stay (T) (T) and the attachment of the pulling wire (18) as described above. The straight line (10) connecting the portion (100) (hereinafter referred to as the force point (12)) is in a state orthogonal to the pulling wire (18).

Therefore, when the pulling wire (18) is pulled, the arm (1) is moved to the rim with the angle (S1) formed by the straight line (10) and the pulling wire (18) kept at about 90 degrees. Swing to the (R) side. The reason why the pressing force of the brake shoe (14) becomes maximum when the angle (S1) formed by the straight line (10) and the vicinity of the force point of the pulling wire (18) is 90 degrees will be described in detail with reference to FIG. ..

When the pulling force (P) of the pulling wire (18) acts on the force point (12) of the arm (1), the arm (1) swings in the direction of the pulling force (P). The force that swings the arm (1) is called force (F). This force (F) acts in the tangential direction of a circle whose radius is the distance from the force point (12) to the swing fulcrum (11), but in this embodiment, as shown by the solid line in FIG. Since (S1) is 90 degrees and the direction of the tensile force (P) matches the swing direction of the arm (1), the magnitude of the tensile force (P) is the swing of the tensile force (P). It matches the magnitude of the force (F) that is the component of the direction.

On the other hand, as shown by the imaginary line in FIG. 7, when the angle (S1) is non-perpendicular, if the pulling wire (18) is pulled with the same pulling force (P), the force is (F) becomes Pcos (90 degrees-S1), which is smaller than the tensile force (P). Further, as shown in the figure, the pressing force (C) and the force (F) of the brake shoe (14) to the rim (R) have a relation of C = Fcos S3, and the corner (S3) is the brake. Since the angle of attachment of the shoe (14) to the arm (1) is constant, the force (F) is proportional to the pressing force (C).

Further, the braking frictional force (acting in the direction perpendicular to the paper surface) is proportional to the pressing force (C). Therefore, when the magnitude of the force (F) matches the magnitude of the tensile force (P), that is, when the angle (S1) is 90 degrees, the braking effect is best. In the brake of this embodiment, the force applied to the brake lever is utilized to the maximum, and the braking efficiency is improved, so the brake operating force is light and easy to handle, and the responsiveness of the brake in an emergency is improved. You can improve and drive more safely.

Further, in the above-mentioned embodiment, this mechanism is adopted for the cantilever type brake, but it can be applied not only to the brake but also to a general caliper brake and the like. Furthermore, the cable guide (G) is not limited to the roller (19) used in this embodiment, and any other mechanism may be used as long as it is a mechanism that can reduce friction with the cable. Further, in the arm (1), if the straight line (10) connecting the swing fulcrum (11) and the force point (12) is orthogonal to the vicinity of the attachment portion of the puller wire (18), as shown in FIG. The arm (1) is formed in a V shape, and the force point (12) and the mounting portion (13) of the brake shoe (14) are provided at both ends of the arm (1) and the swinging fulcrum is provided at the center of the arm (1). (11) may be arranged.

[Brief description of drawings]

FIG. 1 is a surface view of an embodiment of the present invention.

FIG. 2 is a side view of the cable connector.

[Fig. 3] Diagram of the mounting structure of the brake shoe (14)

[Fig. 4] Diagram of the mounting structure of the roller (19)

5 is a sectional view taken along line XX of FIG.

6 is a sectional view taken along line AA of FIG.

FIG. 7 is a diagram showing the relationship between the pulling force of the pulling wire and the pressing force of the brake shoe.

FIG. 8 is an explanatory view of a brake in which the arm (1) has a different structure.

FIG. 9 is an explanatory diagram of a conventional example.

FIG. 10 is a diagram showing a relationship between a pulling force of a pulling wire and a pressing force of a brake shoe in a conventional example.

[Explanation of symbols]

 (1) ・ ・ ・ Arm (11) ・ ・ ・ Swing fulcrum (12) ・ ・ ・ Power point (14) ・ ・ ・ Brake shoe (18) ・ ・ ・ Pulling wire (G) ・ ・ ・ Cable guide (R)・ ・ ・ Rim (T) ・ ・ ・ Seat stay

Claims (1)

[Scope of utility model registration request] 1. A swingable arm (1) disposed on a rim side of a wheel of a stay for supporting a wheel of a bicycle, and the arm.
A brake shoe (14) attached to (1) and a pulling wire (18) for pulling and swinging the arm (1) are further provided, and the arm (1) is connected by the pulling wire (18). ) Is swung, the brake shoe (14) provided on it is pressed against the peripheral side surface of the rim of the wheel.In a bicycle brake, pull it from the swinging end of the arm (1). Wire (1
8) Cable guide such as guide roller on the part deviated to the side
(G) is arranged, and the pulling wire (18) is extended in such a manner that it goes through the cable guide (G), and the distal end thereof is placed in the arm.
Connect to the attachment part (100) of (1), and attach the attachment part (100) and the arm.
A bicycle brake in which the pull wire (18) connecting the cable guide (G) to the arm (1) is at a right angle to the straight line (10) connecting the swing fulcrum of (1).