JPH0451111Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

This invention relates to an outer wire adjustment mechanism in a caliper brake installed on a sports type bicycle such as a competition bicycle.

[Conventional technology]

Side-pull type caliper brakes are commonly used on sports-type bicycles such as competition bicycles. First, its basic structure will be explained with reference to FIG. The caliper brake C is attached to a C-arm with respect to a support shaft 1 extending in the longitudinal direction of the vehicle body, which is fixed to the hawk crown for the front brake, and to a horizontal crosspiece spanning the vicinity of the seat pipe joint of the back hawk for the rear brake. 5 and Y arm 6, each of which is swingably supported. The C-arm 5 and the Y-arm 6 each have a tip that curves and extends to sandwich the tire 3 or rim 4 of the wheel 2 from both sides, and brake shoes 7 and 8 are attached to these tips, respectively. It is being Further, both arms 5 and 6 are always elastically biased by a spring 9 in a direction in which the brake shoes 7 and 8 are separated from each other. The above caliper brake C has an inner wire w whose one end is connected to a brake lever (not shown).
1 and the other end of the double wire consisting of the outer wire w2 inserted into the wire are connected. That is, the end of the outer wire w2 is connected to the actuating arm 11 extending diagonally upward from a suitable part of the Y-arm 6, and is opposite to the tip of the C-arm 5 where the brake shoe is attached across the support shaft 1. The end of the inner wire w1 drawn out from the end of the outer wire is connected to the actuating arm 10 that extends to the side. When the brake lever is operated in the braking direction and one end of the inner wire w1 is pulled toward the brake lever side to give relative movement in the axial direction between the inner wire w1 and the outer wire w2, the end of the double wire on the caliper brake side Actuating arm 10 at the section
The distance between the inner wire connecting portion in the actuating arm 11 and the outer wire connecting portion in the actuating arm 11 is reduced, and as a result, the C arm 5 and the Y arm 6 move each brake shoe 7, 8 around the support shaft 1 while accumulating the spring 9. rotate in the direction in which the distance between the two is narrowed (in the direction of arrow p). At this time, each brake shoe 7, 8 compresses the rim 4 of the wheel 2 from both sides, thereby braking the wheel 2. On the other hand, when the operating force on the brake lever is relaxed, each arm moves in the direction (arrow q direction)
It rotates back to , and the brake is released. By the way, in order to maintain good braking response by the brake, in the natural state, that is,
When the brake lever is in the open state,
It is necessary that each brake shoe 7, 8 be located with a slight clearance from the rim side 4 of the wheel 2. However, the inner wire w1, which is always under tension due to the elasticity of the spring 9 and is subjected to an extremely strong traction force during braking operation, gradually stretches, or the outer wire w2 contracts due to the reaction force, so that the tension in the natural state The distance between the brake shoes 7 and 8 increases, and the effectiveness of the brakes gradually decreases. Also,
As the brake shoes 7 and 8 wear out, the effectiveness of the brake gradually decreases. Therefore, in such side-pull type caliper brakes,
Typically, an outer wire adjustment mechanism 16 is attached to the outer wire connection portion of the actuating arm 11 to adjust the effective length of the outer wire. One typical conventional outer wire adjustment mechanism will be described below with reference to FIGS. 6 to 8. FIG. 7 is an enlarged sectional view taken along the - line of the outer wire adjustment mechanism 16 in FIG. 6, and FIG. 8 is an exploded view thereof. Tip boss portion 20 of actuating arm 11 of Y arm 6
A large diameter hole 2 for holding and accommodating the end of the outer wire w2 is provided in the through hole 21 provided in the upper end head.
3, and an adjustment bolt 17 having an inner wire insertion hole 22 extending through the shaft from the bottom of the large diameter hole.
is inserted in a non-rotatable manner by providing a flat surface on the outer periphery of the threaded portion and making the cross section of the through hole 21 correspond to the cross section of the threaded portion,
An adjustment nut 18 screwed onto the threaded portion of the adjustment bolt 17 is disposed between the upper surface of the boss portion 20 and the head of the adjustment bolt 17. The end of the outer wire w2 is inserted into the large diameter hole 23,
The inner wire w1 drawn out from the outer wire w2 passes through the insertion hole 22 of the adjustment bolt 17 and reaches the inner wire connecting portion 15 of the C-arm 5. Note that reference numeral 19 in the figure is a rubber ring that is fitted into the threaded portion of the adjustment bolt 17 in order to prevent the adjustment bolt 17 from slipping out of the through hole 21 during transportation of the brake as a component. When the effectiveness of the brake becomes weak, when the adjusting nut 18 is rotated clockwise, the adjusting bolt 17 overcomes the tension of the outer wire w2 without rotating and is pulled up against the boss portion 20 in the figure. This means that the effective length of the outer wire w2 has become longer by the upward movement of the adjustment bolt 17, which cancels out the elongation of the inner wire w1 and extends each brake shoe 7, 8 to the rim 4.
It can be located very close to.

[Problems that the idea aims to solve]

By the way, the conventional outer wire adjustment mechanism 16 described above requires an adjustment nut 18 and a rubber ring 19 in addition to the adjustment bolt 17, and thus has a large number of parts, which limits cost reduction. There is a problem in that a complicated assembly operation is required, such as inserting the adjusted bolt 17 into the through hole 21 of the boss portion 20 and then fitting the rubber ring 19 into the threaded portion of the bolt. Further, in order to prevent the adjusting nut 18 from becoming unintentionally loosened after adjustment, an engaging groove 25 is provided on the upper surface of the boss portion 20, and the adjusting nut 18 is provided with an engaging groove 25 on its lower surface. It must be made special so as to have the engaging protrusion 24, which increases the cost. In addition, although this is generally true for side-pull type caliper brakes, in the case of a front brake, due to the shape of the bicycle frame and the mounting position of the brake, the handle rotation axis of the outer wire adjustment mechanism 16 in the Y arm 6 is If the handle is rotated greatly and strongly during a fall, etc., the outer wire adjustment mechanism, especially the boss portion 20 of the actuating arm 11, will interfere with the lower pipe of the frame.
The outer periphery of the frame may strongly collide with the lower pipe of the frame. At this time, the lower pipe may be damaged, the paint may peel off, causing rust, and the support shaft 1 on the caliper brake side may be bent and deformed due to the reaction from the impactful collision. This may cause problems such as hindering the smooth rotation of each arm. This invention was devised under the above circumstances, and it solves the various problems mentioned above with the outer wire adjustment mechanism of the conventional bicycle caliper brake, and by simplifying the structure. To provide a new outer wire adjustment mechanism that solves the problem of reducing the number of parts and ease of assembly, and at the same time solving the above-mentioned problem caused by the interference of the orbit of the outer wire adjustment mechanism with the lower pipe of the frame. is the issue.

[Means to solve the problem]

In order to solve the above problems, the invention of the present application takes the following technical measures. That is, the present invention has a C-arm and a Y-arm that are swingably supported on a support shaft attached to an appropriate part of the vehicle body.
In a bicycle caliper brake equipped with an arm, a screw hole in a boss part provided at an appropriate part of the Y arm,
The outer wire adjustment mechanism is formed by screwing together an adjustment bolt that accommodates and holds one end of the outer wire so as to be able to move forward and backward. A cut groove that connects from a predetermined position to the outer periphery of the boss portion is formed on the end surface of the boss portion, while a detent protrusion made of an elastic material such as resin or rubber is formed on the outer periphery of the counterbore portion and that fits into the cut groove. A friction imparting member having a center hole for holding an adjustment bolt is fitted while being elastically contracted so that the inner diameter of the center hole is smaller than the mountain diameter of the adjustment bolt, and
A buffer portion extending radially outward from the outer periphery of the boss portion is integrally formed at the tip of the anti-rotation projection.

[Action and effect]

In the conventional outer wire adjustment mechanism, a screw hole was not provided in the boss portion of the proper portion of the Y arm, and the threaded portion of the adjustment bolt was simply inserted. Therefore, it was necessary to attach a rubber ring to prevent the adjustment bolt from falling off. In the present invention, a screw hole is provided in the boss portion, and an adjustment bolt is screwed into the screw hole, and the screw is forcibly screwed into the center hole of the reduced-diameter friction imparting material while standing. . Therefore, since its rotation is prevented by the friction imparting member, the adjustment bolt does not fall off the Y-arm, and there is no need to attach a rubber ring, improving work efficiency and reducing the number of parts. Decrease. Furthermore, the frictional force between the adjusting bolt and the friction-applying member is constant regardless of the tension of the brake wire, and the friction-applying member is fixed in the cut groove of the boss portion by the rotation prevention protrusion. This prevents the adjustment bolt from rotating easily and causing deviations in the adjustment position. Therefore, the brake performance is stabilized, and unlike the conventional example, there is no need for a special adjustment nut or special processing, which reduces costs and eliminates the need for nuts, resulting in weight reduction. . Further, a buffer portion extending further radially outward from the outer periphery of the boss portion is integrally formed at the tip of the anti-rotation projection of the friction imparting member. This cushioning part is designed to prevent damage to the lower pipe by intervening between the outer periphery of the boss and the lower pipe when the handle is rotated a lot and the boss part of the Y arm collides with the lower pipe of the frame. In addition to preventing
It is also possible to absorb the impact force of a collision and prevent brake performance from being impaired due to deformation of the caliper brake support shaft or the like.

[Explanation of Examples]

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 5. In addition, in these figures, the same reference numerals are given to the same members as in the conventional example. This embodiment is an example in which the present invention is applied to a side-pull type caliper brake for the front wheel of a bicycle. As shown in FIGS. 1 and 3, in this embodiment, a boss portion 20 at the tip of the actuating arm 11
a screw hole 26 for screwing the adjustment bolt 33 into the
is formed. A counterbore 28 for accommodating the friction imparting member 27 is formed at the upper end of the screw hole 26, and a cut groove 29 is formed from a predetermined position on the inner periphery of this counterbore 28 to the outer periphery of the boss. ing. The inner diameter of this counterbore portion 28 is set to be smaller than the outer diameter of the friction applying member 27 in its natural state, which will be described later, and the depth is set to be equal to or greater than the thickness of the friction applying member 27. In addition, in this embodiment, the cut groove 29 connected to the outer periphery of the boss portion extends toward the rear of the bicycle in order to prevent the buffer portion 30 of the friction imparting member 27, which will be described later, from damaging the lower vibrator. Furthermore, in order to increase the thickness of the buffer part 30 and increase the buffer capacity, it is formed so as to taper deeper toward the outer periphery. On the other hand, the friction imparting member 27 has a donut disk shape made of an elastically deformable material such as synthetic resin or rubber, and as shown in FIGS. 4 and 5, the friction imparting member 27 is A cut groove 33 is formed which has an outer diameter larger than the inner diameter of the counterbore portion 28 and is provided so as to connect the outer periphery and the center hole 32. As shown in FIGS. 5a and 5b, the cut groove 33 is designed to easily elastically contract when the friction imparting member 27 is fitted into the counterbore portion 28. When fitted into the counterbore portion 28 and elastically contracted, the center hole 32 is larger than the thread diameter of the adjustment bolt 33, that is, the root diameter of the screw hole 26 of the boss portion 20, as shown in FIG. 4b. It is set to be smaller. Further, on the outer periphery of the friction imparting member 27 on the opposite side to the cut groove 33, a rotation preventing protrusion 34 is provided for engaging with the cut groove 29 formed in the counterbore portion, and the tip of the protrusion A buffer portion 30 extending radially outward from the outer periphery of the boss portion 20 is integrally formed therein. The buffer portion 30 is formed so that its thickness tapers outward in the radial direction in order to increase the buffering capacity. Although not shown in the drawings, a buffer portion may be formed along the outer periphery of the boss portion in order to increase the buffer capacity. As shown in FIGS. 4a and 4b and 5a and 5b, when the friction applying member 27 is fitted into the counterbore portion 28, the friction applying member 27 is in an elastically reduced diameter state. At this time, as shown in FIG. 4b, the center hole 32 becomes smaller than the top diameter of the adjustment bolt 33, that is, the bottom diameter of the screw hole 26 formed in the boss portion. An adjustment bolt 33 is inserted into this diameter-reduced center hole 32.
When it is forcibly screwed in, the inner wall of the center hole 32 of the friction imparting member 27 is screwed forward while elastically expanding in diameter, and is screwed into the screw hole 26 of the boss portion 20. At this time,
A frictional force is generated between the inner wall of the center hole 32 and the threaded portion of the adjusting bolt 33, and this frictional force is applied to the adjusting bolt 33.
Acts as a force to prevent loosening and rotation. Therefore, the adjustment bolt 33 is held by the frictional force in a state in which it has been advanced to a desired amount of progression, and its screwed position will not be deviated even if some external force or impact is applied. Also in this embodiment having the above configuration, the end of the outer wire w2 is inserted into the large diameter hole 23 of the head of the adjustment nut 33, and the inner wire w1 pulled out from the outer wire w2 is inserted into the adjustment bolt 33.
The inner wire connecting portion of the C-arm is reached through the shaft through hole 22 of the C-arm, and the movement of each arm when the brake lever is operated is the same as in the conventional example. In this embodiment, when the effectiveness of the brake becomes weak, when the adjusting bolt 33 is rotated counterclockwise, the adjusting bolt 33 overcomes the tension of the outer wire w2 and the frictional force of the friction applying member 27, and moves away from the boss portion 20. It will be rotated in the direction in which it comes out, and it will rise upwards in the figure relative to the boss portion 20. As a result, as in the conventional example, the effective length of the outer wire w2 is increased by the upward movement of the adjustment bolt 33, and therefore, the elongation of the inner wire w1 is offset, and each brake shoe 7, 8 can be located very close to the rim 4. The adjustment bolt 33 after adjustment is screwed into the screw hole of the boss portion 20, and its rotation is suppressed under normal conditions due to the frictional force with the friction imparting member 27, so that the adjusted position may become incorrect. This eliminates the need for an adjustment nut having an engaging protrusion that was required in the conventional example. Therefore, the number of parts can be reduced and the weight of the nut can be reduced. Further, the buffer portion 30 integrally formed at the tip of the anti-rotation protrusion 34 of the friction imparting member 27 extends further outward from the outer periphery of the boss portion, so that the boss portion 20 and the lower pipe of the frame may be damaged due to a fall or the like. It is located between the outer periphery of the boss and the lower pipe in the event of a collision. This buffer part 30 prevents the lower pipe from being damaged, and also absorbs the impact force of a collision, thereby preventing deterioration of brake performance due to deformation of the caliper brake support shaft 1, etc. This will also increase the product value of the bicycle. Furthermore, in this embodiment, the friction imparting member 2
7 is elastically fitted into the counterbore formed at the end of the screw hole 26 of the boss portion 20, and then the adjustment bolt 3
Since it is only necessary to screw the parts 3 together, the installation work is extremely simple, and the workability of assembling the brake is improved. Furthermore, since the frictional force that suppresses the rotation of the adjustment bolt 33 is generated simply by screwing the adjustment bolt 33 together, the adjustment bolt 33 will not come off during transportation, and a rubber ring is not required, so the above-mentioned adjustment nut is unnecessary. In addition to this, the number of parts is further reduced, making parts management easier and reducing costs. The scope of the present invention is not limited to the above-described embodiments. The embodiment is an example in which the present invention is applied to a side-pull type caliper brake for the front wheel of a bicycle, but the present invention can also be applied to a side-pull type caliper brake for the rear wheel, a center-pull type caliper brake, etc., and a wire for a brake device that uses a brake wire. Can be applied to adjustment mechanisms.

[Brief explanation of the drawing]

FIG. 1 is a front view of the embodiment of the present invention, FIG. 2 is an exploded perspective view of the embodiment of the present invention, and FIG. 3 is an enlarged sectional view taken along the - line in FIG. 1 of the present invention.
FIGS. 4a and 4b are explanatory diagrams of the action of the invention, FIGS. 5a and 5b are diagrams of the action of the friction imparting member of the invention,
Fig. 6 is an explanatory diagram of the operation of the conventional example, Fig. 7 is an enlarged sectional view taken along the - line in Fig. 6 of the conventional example, and Fig. 8
The figure is a diffusion exploded diagram of a conventional example. DESCRIPTION OF SYMBOLS 1... Support shaft, 5... C arm, 6... Y arm, 20... Boss part, 26... Screw hole, w2... Outer wire, 33... Adjustment bolt, 28... Counterbore part, 29... ...kerf, 34...rotation protrusion,
32... Center hole, 27... Friction imparting member, 30...
...buffer section.

Claims (1)

[Scope of utility model registration request] In a bicycle caliper brake equipped with a C-arm and a Y-arm that are swingably supported on a support shaft attached to an appropriate part of the vehicle body, one end of the outer wire is accommodated in a screw hole in a boss provided in an appropriate part of the Y-arm. The outer wire adjustment mechanism is formed by screwing together a holding adjustment bolt so as to be able to move forward and backward, and a counterbore is formed at one end of the screw hole of the boss, and the boss is inserted from a predetermined position on the inner periphery of the counterbore. A cut groove connected to the outer periphery is formed on the end face of the boss portion, and the counterbore portion has a rotation prevention protrusion made of an elastic material such as resin or rubber on the outer periphery that fits into the cut groove and holds the adjustment bolt. A friction imparting member having a center hole for rotation is fitted while being elastically reduced in diameter so that the inner diameter of the center hole is smaller than the mountain diameter of the adjustment bolt, and An outer wire adjustment mechanism for a bicycle caliper brake, characterized in that a buffer portion is integrally formed that extends radially outward from the outer periphery of the boss portion.