JPS6123941Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a disc brake device for a bicycle, which is equipped with an adjustment mechanism that can set a constant pad gap between fixed pads and movable pads that sandwich a brake disc.

Hitherto, disc brake devices of this type have been provided with various configurations, but all of them have the disadvantage that they have a large number of components, are complex in structure, and require time and effort to adjust. In particular, the disc brake device must be installed in a limited space, and the gap between the pads must be adjusted not only when the disc brake device is installed, but also when the pads are worn or damaged. It is encouraged.

This invention was devised as a result of intensive research in view of the above circumstances, and its purpose is to simplify the adjustment mechanism for the pad gap in a disc brake device, and to make it easy for anyone to perform the adjustment operation. The object of the present invention is to provide a highly reliable disc brake device that can be easily operated.

Another object of this invention is to provide a disc brake device that utilizes an adjustment mechanism to provide a parking lock function.

Still another object of this invention is to provide a disc brake device in which the brake disc is kept in constant contact with a fixed pad, so that the pad gap can be set extremely narrow and the braking feeling can be enhanced.

A preferred embodiment of the disc brake device according to this invention will be described below with reference to the drawings.

The disc brake device shown in Figs. 1 and 2 includes a fixed pad 1 and a movable pad 2 that sandwich a brake disc D from both sides, a pressure mechanism that pushes the movable pad 2, and a gap between the pads that is set constant. It consists of an adjustment mechanism and a casing C that houses these mechanisms.

That is, in the illustrated example, the casing C is formed from divided first and second blocks C1 and C2.

A fixing pad 1 is screwed onto this first block C1 via a mounting screw.

Next, a gap is provided in the second block C2 in which the pressure mechanism and the adjustment mechanism are installed in series, and passes through the block C2 in the left-right direction in FIG.

This gap includes a stepped hole H1 that opens toward the brake disc D, and a cam storage chamber H2 that communicates with the hole.
and a guide hole H3 that is coaxial with the stepped hole H1, communicates with the cam storage chamber H2, and opens on the outer surface of the casing C2.

The stepped hole H1 consists of a large diameter circular hole part and a small diameter concentric circular hole part, and a piston-shaped pushing member 5 that holds the movable pad 2 is slidably penetrated through the large diameter circular hole part, and a A transmission ball 7 made of steel is housed in the small-diameter concentric hole through a washer 6 that communicates with the pushing member 5, and the pushing member 5 to the transmission ball 7 are guided in the stepped hole H1 in the axial direction of the hole. It is set so that it can be moved.

On the other hand, a return plate 8 is connected to the pushing member 5 as a means for urging the pressure mechanism in the brake release direction.

As shown in more detail in FIG. 7, the return plate 8 has a substantially half-doughnut shape with a casing attachment hole 9 in the center, and one end of contracted return springs 10, 10 is secured to both shoulders of the return plate 8, as shown in more detail in FIG. It also has claws 11, 11 that protrude inward at both arm ends. The claw portions 11, 11 are fitted into locking grooves 12, 12 formed in the peripheral wall of the pushing member 5 and are connected.

Therefore, when the brake is released, the return spring 1
The return plate 8 is urged in the direction of separation from the brake disk by the elastic force of 0, and this urging force is transmitted to the pushing member 5 that interlocks with the return plate 8.

Next, a plate-shaped cam 13 is installed in a cam storage chamber H2 communicating with the stepped hole H1 in an upright manner, and is in contact with the transmission ball 7.

This plate-shaped cam 13 has an upper end that is connected to the brake arm 1.
It is connected to 4.

In the illustrated example, the brake arm 14 has a distal end that holds one end of the brake wire W, and a proximal end that is pivotably attached to the outer wall of the casing C2 above the storage chamber H2 and is attached so as to be able to return via an expanded spring 15. It consists of a powerful structure.

Further, this brake arm 14 has a channel-shaped cross section and has a pivot shaft 16 in the middle that passes through the groove, and the upper end of the plate-shaped cam 13 is pivotally attached to the pivot shaft 16. has been done.

Therefore, the plate-shaped cam 13 can move up and down in conjunction with the rotation of the brake arm 14, and can also slide on the pivot shaft 16 and move in parallel in the direction of the brake disk.

The plate-like cams 13 connected in this manner have a tapered wall surface 13a that gradually protrudes toward the brake disk side on the transmission ball contact side, and
A dish-shaped concave portion 13b is bored on the back surface thereof.

The tip of an adjustment ball 17 held by an adjustment means 18 fixedly movable in the direction of the brake disc is fitted into the dish-shaped concave portion 13b.

In the case of this embodiment, an adjustment screw 18 made of a threaded body having a U-shaped cross section is used as the adjustment moving means. The adjustment screw has a recessed portion that fits and supports a part of the adjustment steel ball via a washer, and is provided with a knob portion 19 for rotating the adjustment screw on the outside. The adjustment screw 18 is screwed into a guide hole H3 that penetrates from the outer surface of the casing C2 to the cam storage chamber H2, and can be freely moved forward and backward in the direction of the hole axis by rotation of the knob 19.

In this way, each component is arranged in series and the first
Block C1 and second block C2 are assembled using mounting bolts V. Of course, the casing C may be formed integrally instead of being divided into parts as in this embodiment.

In the disc brake device having the above configuration, the braking operation will be explained based on FIG. 3.

Now, when the brake wire W is pulled by actuation of a brake lever (not shown), the brake arm 14 rotates. When the plate cam 13 moves up due to the rotation of the brake arm 14, the adjustment screw 18
The steel ball 17, which is fixed in the direction of the brake disc, rolls into contact with the plate-shaped cam 1.
3, and climbs over the slope of the dish-shaped concave portion 13b provided at 3. As a result, the plate-like cam 13 moves on the pivot shaft 16 of the brake arm by the groove height _l1 of the concave portion 13b toward the brake disk. At the same time, the transmission ball 7 climbs the tapered wall surface 13a of the plate-shaped cam 13 by rolling contact, thereby pushing the transmission ball 7 by a component l ₂ of the inclined surface toward the brake disk.

Therefore, due to the upward movement of the plate-shaped cam, the movable part is pressurized by l ₁ +l ₂ minutes towards the brake disc side via the transmission ball 7 and the pushing member 5, and the brake disc D is pressed against the fixed pad 1 and the movable part. 2 provides narrow pressure braking.

On the other hand, when the brake is released, the brake arm 14 returns due to the elastic force of the spring 15, and the plate-shaped cam 13 descends and returns to its original position. At this time, each ball 7, 17 moves in the opposite direction to that during braking, and due to the repulsive force of the return plate 8 which is urged in the direction of separating the brake disk, both the movable pad 2 and the plate-shaped cam 13 are brought to the position before braking. revive it.

Next, explaining the pad gap adjustment function based on FIG. 4, the plate-shaped cam 13 is rotated about the pivot shaft 16 of the brake arm 14, and the steel ball
7 is displaced to the set position where it rolls over the inclined surface of the dish-shaped recess 13b in the left-right direction by contact.

In this set state, screw the tilt adjustment screw to move the brake disc D to a position where both pads 1 and 2 hold it.

At this position, when the plate-like cam 13 is returned to its original state (reset position), the tip of the steel ball will return to the concave portion 1.
3b, and due to the elastic force of the return plate 8, the movable pad 2 to the plate-shaped cam 13 are moved together by the groove height _l of the concave portion 13b in the direction of separation from the brake disk. .

As a result, an appropriate clearance can be set between the pads 1 and 2, that is, between the brake disc D and the movable pad 2. This clearance matches the groove height _l1 of the concave portion 13b, so this groove height
Depending on the setting of _l1 , it is possible to set the gap appropriately. (In the figure, a indicates the set position, and b indicates the reset position.) In this embodiment, a dish-shaped concave portion is used as the adjustment cam, but if the plate-shaped cam 13 has a tapered surface that protrudes in the setting direction, Regardless of the shape of the concave part, slope, etc. Also, the adjustment ball 17,
The transmission ball 7 can be replaced by a known rotor that rolls into contact with the cam surfaces 13a and 13b.

As described above, the disc brake device according to the present invention requires the plate-shaped cam to be rotated and displaced from the set position to the reset position in order to adjust the pad gap, and the cover body 21 as shown in FIG. An interlocking structure of the sliding plate 20 and the sliding plate 20 is adopted.

The sliding plate 20 has a pair of claws 20a, 20a that protrude outward from one side of the brake base, and the claws 20a, 20a engage with the lower end of the plate-shaped cam 13 so as to sandwich it. There is.

On the other hand, the cover body 21 is attached to the knob 1 of the adjustment screw 18.
9 and hinged to one end of the casing to open and close like a door.

This cover body 21 is integrally formed with a sliding claw 22 that engages with one end of the sliding plate 20, so that when the cover body is opened, the sliding claw rotates with the rotation of the cover body, and the sliding plate When the slide plate 20 is moved to the set position shown by the dashed line and the cover is closed, the sliding claw returns to return the sliding plate 20 to the reset position shown by the solid line.

In this way, in the above structure, the sliding claw and the sliding plate are moved only by the opening/closing operation of the cover body 21, and the plate-shaped cam 1 is moved.
3 can be rotated from the set position to the reset position, and adjustment operations can be performed accurately and easily.

Alternatively, this displacement means may simply extend the lower end of the plate-shaped cam to the outside of the casing to form the operating rod portion 23 as shown in FIG.

In this case, the operating rod 23 may be pushed with a finger or the like to rotate it to the set or reset position.
In this case, a known locking mechanism may be added to temporarily lock the operating lever 23 in the set position and reset position.

It goes without saying that the brake disc used in the disc brake device of this invention may have any configuration, but in the case of this embodiment, the brake disc D is composed of a disc main body D1 fixed to the wheel hub, and a disc main body D1 fixed to the wheel hub. comprises a separately formed disc plate D2, and the disc plate D
2 is fitted and held in the main body D1 so as to be movable or tiltable within a certain range in the axial direction, and both are integrally engaged in the rotational direction.

Therefore, if the disc plate D2 is set in a state where it is always in contact with the fixed pad 1 when installed, the clearance between the disc plate D2 and the movable pad 2 can be set and maintained extremely narrow, and the braking force can be maintained. This is preferable because it strengthens the braking force and improves the feeling of braking.

Furthermore, the disc brake device of this invention can also be provided with a parking lock mechanism.

That is, if the adjustment screw 18 is screwed forward in the same way as in the adjustment operation, and the brake disc D is pressed between the pads 1 and 2, and the adjustment screw is fixed using a detachable key mechanism (not shown), the brake can be adjusted. The vehicle can be restrained and parked via disk D.

In this way, the movable pad can be moved in the braking direction using the adjustment screw that can be operated from the outside, so a parking lock function can be provided. At this time, it is not necessary to operate the plate-shaped cam 13 or not, but it is preferable to rotate the plate-shaped cam 13 to the set position and release the parking lock by simply releasing the key and displacing the plate-shaped cam 13 to the reset position. .

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional view of a disc brake device according to a preferred embodiment of this invention, FIG. 2 is a front view of the same, and FIG. 3 is an explanatory view showing the brake braking operation, where a is before braking and b is during braking. Show the time. FIG. 4 is an explanatory diagram showing the pad gap adjustment action, with a indicating the setting and b indicating the resetting. FIG. 5 is an explanatory diagram showing an embodiment of the displacement means for the adjustment operation, and FIG. FIG. 7 is a sectional view of a main part showing different embodiments of the means, and a front view of a return plate device showing an example of a return member that urges the pressure mechanism in the releasing direction. 1 is a fixed pad, 2 is a movable pad, 5 is a pushing member, 7 is a transmission ball, 13 is a plate-shaped cam, 13a is a tapered wall surface exemplified as a pressure cam surface, and 13b is a concave portion exemplified as an adjustment cam surface. , 17 is an adjustment ball, 18 is an adjustment screw exemplified as an adjustment means,
D is the brake disc.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A fixed pad and a movable pad disposed opposite to each other on both sides of a brake disc mounted on a wheel, and a fixed pad and a movable pad that are capable of pushing the movable pad in the braking direction and that are constantly A pushing member that is biased in the brake release direction, a transmission rotor that transmits thrust to the pushing member, and a brake arm that contacts the transmission rotor in series and rotates due to the traction force of the brake wire. a plate-shaped cam that is movable in the brake braking direction or brake-release direction and rotatably connected in the circumferential direction; a pressure cam surface that converts the force into thrust and transmits it to the transmission rotor; an adjustment cam surface formed on the back side of the pressure cam surface that protrudes at least in the plate-shaped cam adjustment direction; and a tip end on the adjustment cam surface. It consists of an adjusting rotor that is removably fitted in and held by an adjusting means that is fixedly movable in the braking direction or releasing direction, and the plate-like cam is rotated and the adjusting means is moved in the braking direction. A disc brake device characterized in that a clearance between pads can be set to a predetermined value by moving the pads. (2) A sliding plate with which the rotating operation means of the plate-shaped cam engages on the lower end side of the plate-shaped cam, a cover body hinged to the casing and capable of opening and closing, and the cover body integrally formed with the above-mentioned It consists of a locking pawl that locks onto a sliding plate, and when the cover body is opened, the sliding plate is moved to displace the plate-shaped cam to the set position, and when the cover body is closed, the sliding plate is returned to the plate-shaped cam. The disc brake device according to claim 1, characterized in that the cam is returned to the reset position. (3) Utility model registration claim 1, characterized in that the rotating operation means for the plate-shaped cam extends the end of the plate-shaped cam to the outside of the casing to provide a manual operation part.
Disc brake device as described in section. (4) The disc brake device according to claims 1 to 3 of the utility model registration claim, characterized in that the brake disc is in contact with the fixed pad when the brake is not applied. (5) Utility model registration claim No. 1, characterized in that the adjusting means consists of a screw body with a U-shaped cross section, supports a part of the adjusting rotor in the recessed part, and has a knob part formed on the outer surface. The disc brake device according to item 1. (6) The disc brake device according to claim 1, wherein the periphery of the raised portion of the adjustment cam surface is formed into an inclined surface.