JPH0442232Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention describes a phenomenon in which the front fork contracts and the front of the vehicle body sinks during braking in motorcycles and tricycles (nose dive phenomenon).
This invention relates to a device for preventing sinking of the front part of a vehicle body, which can suppress this by using the braking torque of the brake.

Prior art and its problems In motorcycles and tricycles, when a telescopic front fork consisting of a fork pipe and a bottom case that are mutually slidable in the axial direction is used to support the front wheel, during braking,
The inertial force acts in a direction that causes the front fork to contract, causing the front fork to sink. In order to prevent this phenomenon, that is, the nose dive phenomenon, various types of anti-sinking devices (anti-nose dive devices) have been proposed.

As one example, as disclosed in Japanese Patent Application Laid-Open No. 58-49587, there is known a mechanism that has a plurality of link members and transmits braking torque to the operating part of the contraction motion regulating means. However, when a plurality of link members are used, the number of parts is large, the structure becomes complicated, and the cost of manufacturing the vehicle increases.

Means and Effects for Solving the Problems An object of the present invention is to provide a device for preventing the front of a small vehicle body from sinking, which has a simplified operating mechanism.

The purpose of this is to support a caliper swingably on the front axle in a small vehicle equipped with a telescopic front fork with a built-in damping force generation mechanism and a disc brake device for braking the front wheels.
A connecting rod is provided on a protruding piece protruding from the back of the bottom case at a position outward from the outer periphery of the rotary plate (disc) so as to be swingable in the longitudinal direction of the vehicle body, and the intermediate part of the connecting rod and the caliper are connected. This is achieved by connecting the shaft member to the caliper in a swingable manner through a shaft cylinder having an eccentric shaft hole, and by connecting the tip of the connecting rod to the operating part of the contraction motion regulating means. Ru.

According to such a configuration, during braking, a braking torque that swings and displaces the caliper toward the front of the vehicle body using the front axle as a fulcrum is transmitted to the connecting rod via the shaft member and the shaft cylinder fitted thereto, The connecting rod swings forward of the vehicle body using the connecting point with the protruding piece on the back surface of the bottom case as a fulcrum. As a result, the operating piece is pushed by the lower end of the connecting rod, the contraction motion regulating means is operated, the main communication oil passage of the damping force generating mechanism is blocked, and the contraction motion of the front fork is restricted.

Embodiment Hereinafter, an embodiment of the present invention shown in FIGS. 1 to 3 will be described.

FIG. 1 shows a left front fork 30L of a motorcycle and an associated contraction motion regulating means 60.
is shown as a schematic side view with main parts cut away, and FIG. 2 shows this as a schematic sectional view seen from the rear side of the vehicle body. Left and right front fork 30L, 30R
These are connected to each other at the lower end of the front axle 1.
A rotary plate (disc) D is screwed onto the side surface of a flange portion 14 of a front wheel 12 rotatably supported by the front axle 10. Further, on the front axle 10, a hydraulic caliper 20, which together with the rotating plate D constitutes a disc brake device, is swingably supported so as to be located inside the left front fork 30L. Caliper 20 is an opposed type (opposed type).
type), and two sets of four caliper cylinders 23 are formed in the caliper body 22.
A caliper piston 24 is fitted into and retracted from each of the two, so that the caliper piston 24 presses the back surface of two sets of friction pad members 26 supported by hanger pins 28.

The left and right front forks 30L and 30R are
Although it is a telescopic type, the left front fork 30L is equipped with the vehicle body front sink prevention device according to the present invention, so the front fork 30L will be described below.

Front fork 30L has bottom case 34
The main member is a fork pipe 32 that is slidably fitted into the bottom case 34. A protruding piece 36 is provided on the back of the bottom case 34.
is integrally provided, and a connecting rod 70 is attached to the protruding piece 36.
is swingably supported at its upper end 72. The upper end 72 of the connecting rod 70 has a bifurcated shape, and the upper end 72 sandwiches the protruding piece 36 from both the left and right surfaces, and the screw 76 that is screwed into the upper end 72 is connected to the cylinder 78. is passed through the support opening of the protrusion piece 36 into which the protrusion piece 36 is fitted. Therefore, the connecting rod 70 can freely swing in the longitudinal direction of the vehicle body using the screw 76 as a support shaft.

A circular shaft cylinder 80 having an eccentric circular hole 80a is fitted into the opening formed in the middle part of the connecting rod 70, and a flanged cylinder 84 is fitted into the circular hole 80a (the third Furthermore, a screw 86 that passes through the arm member 22a extending from the caliper body 22 so as to straddle the connecting rod 70 and also passes through the flanged cylinder 84 in a tight-fitting state is inserted between the caliper cylinders 23, 23. , is screwed to the caliper body 22.

Further, the lower end portion 74 of the connecting rod 70 is formed into a bifurcated shape, and a cylinder 88 and a flange are attached to the opening formed in the operating piece 64 of the contraction motion regulating means 60 described later, with the outer end portion thereof being located between the bifurcated portions. A cylinder 90 is fitted into the cylinder 90, and a screw 92 passing through the cylinder is screwed into the bifurcated lower end 74.

Next, the internal structure of the front fork 30L and the contraction motion regulating means 60 attached to the front fork 30L will be explained.

The lower end of the seat pipe 38 is fixed to the inner lower end of the bottom case 34 with a screw 40, and the partition fitting 42 is fixed to the bottom of the bottom case 34 by the attachment relationship. The upper end portion (not shown) of the seat pipe 38 is slidably and oil-tightly fitted into the fork pipe 32.

And the bottom case 34 and the seat pipe 38
The A chamber defined by the A chamber and the B chamber in the seat pipe 38 are filled with buffer oil. cylinder chamber C, a communication passage 46 formed in the bottom case 34, an opening 48 formed in the partition fitting 42,
The buffer oil flows from the A chamber to the B chamber or from the B chamber to the A chamber via a main communication oil passage formed by an opening 50 formed in the sheet pipe 38.

In addition, a contraction movement restriction means 60 is attached to the rear and front surfaces of the lower end of the bottom case 34, and the contraction movement restriction means 60 is oil-tightly screwed and fixed to a seat surface formed on the bottom case 34. Cylinder chamber C
a housing 62 defining an anti-dive piston 66;
4, a compression coil spring 68 that urges the operating piece 64 in the backward direction, and a rubber cover tube (boot).
69 and the front surface of the lower end of the bottom case 34, with an opening 44A and a bypass oil passage 46A inside.
The main body includes a protrusion 34A having a diameter of 34A, and a flow rate adjusting orifice member 67 that is fitted into the bypass oil passage 46A, has a plurality of orifices of different diameters, and is rotated by its grip 67a. There is. When the anti-dive piston 66 moves forward and comes into contact with the wall surface of the bottom case 34 around the opening 44, the main communication oil passage is cut off, and the orifice 67 inserted into the bypass oil passage 46A is selected. Room A and room B will communicate through the orifice.

This embodiment is constructed as described above, and when braking, pressure oil is discharged from the hydraulic master cylinder and the hydraulic pressure in the caliper cylinder chamber increases, each caliper piston 24 moves forward, and the two sets of caliper pistons 24 move forward. A rotating plate D in which the friction pad member 26 is slidably displaced along the hanger pin 28 and rotates in the direction of arrow E.
Friction and pressure. The rotational force of the caliper 20 around the front axle 10 generated by this frictional force is
6 to the connecting rod 70, and the connecting rod 70
swings in the direction of arrow F about the screw 76, and the operating piece 64 connected to the lower end 74 of the connecting rod 70 via the screw 92 is pushed, and its tip, that is, the anti-dive piston 66 comes into contact with the wall surface of the bottom case 34. Thus, the braking torque generated between the rotary plate D and the friction pad member 26 is transmitted to the protruding piece 36 of the bottom case 34 and the wall surrounding the opening 44 via the connecting rod 70, thereby achieving desired braking.

Then, the anti-dive piston 66 of the contraction movement restricting means 60 moves forward and comes into contact with the wall surface of the bottom case 34, so that the main communication oil passage from the opening 44 to the cylinder chamber E to the communication passage 46 is blocked. Despite the force exerted by the fork pipe 32 to move further into the bottom case 34, the buffer oil in the A chamber passes through the orifice 67 selected (according to the passenger's preference).
Because it gradually flows into chamber B under large flow resistance,
The front fork 30L cannot be rapidly retracted, and the sinking of the front part of the vehicle body is effectively restricted.

The reason why the circular hole 80a of the circular shaft tube 80 is made eccentric with respect to the outer circumference is to ensure that the caliper 20 and the connecting rod 70 swing at different centers of swing.

Furthermore, the operating mechanism of the contraction motion regulating means 60 using a single connecting rod 70 has a simpler structure and fewer parts than conventional ones, which improves vehicle assembly work efficiency and reduces manufacturing costs. may be planned.

Effects of the Invention As is clear from the above explanation, in the present invention, in a small vehicle equipped with a telescopic front fork and a disc brake device for braking the front wheels, the caliper is swingably supported on the front axle, and the rotating plate is A connecting rod is provided on a protruding piece protruding from the back surface of the bottom case at a position outward from the outer periphery, and a connecting rod is provided in a swingable manner, and the intermediate portion of the connecting rod and the caliper are connected through a shaft cylinder having an eccentric shaft hole. , is connected to the caliper so as to be swingable by a shaft member, and the tip of the connecting rod is connected to the operating part of the contraction motion regulating means provided on the front fork, so that the swinging force of the caliper due to braking is reduced. The swinging force of the connecting rod is transmitted to the moving parts without difficulty, and the main communication oil passage of the damping force generating mechanism is cut off by the operation of the contraction motion regulating means.
The contraction movement of the front fork is regulated. In this way, the structure in which the displacement of the caliper is transmitted to the contraction motion regulating means using a single connecting rod is simple and achieves a reduction in the number of parts, a reduction in the weight of the vehicle body, and a reduction in manufacturing costs. be able to.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view with main parts cut away showing a left front fork of a motorcycle equipped with a contraction movement regulating means according to an embodiment of the present invention, and FIG. 2 is a schematic sectional view of the left front fork as seen from the rear of the vehicle body. FIG. 3 is an enlarged sectional view showing a connecting portion between the caliper and the connecting frame. 10... Front axle, 12... Front wheel, 14... Hub, 20... Caliper, 22... Caliper body, 23... Caliper cylinder, 24... Caliper piston, 26... Friction pad member, 28 …
... Hanger pin, 30L, 30R ... Front fork, 32 ... Fork pipe, 34 ... Bottom case, 36 ... Projection piece, 38 ... Sheet pipe, 40 ... Screw, 42 ... Partition metal fitting, 44
...Opening, 46...Communication path, 48...Opening, 50
...opening, 60...shrinkage movement regulating means, 62...housing, 64...operating part, 66...anti-
Dive piston, 67... Orifice member, 6
8... Compression coil spring, 69... Cover tube, 7
0... Connecting rod, 72... Upper end, 74... Lower end, 76... Screw, 78... Cylindrical body, 80... Circular shaft cylinder, 84... Flammed cylinder, 86... Screw, 88
...Cylinder, 90...Cylinder with flange, 92...Screw.

Claims (1)

[Scope of Claim for Utility Model Registration] A telescopic front fork with a built-in damping force generation mechanism, which contracts the front fork consisting of a fork pipe and a bottom case by cutting off the main communication oil passage of the damping force generation mechanism during braking. In a small vehicle equipped with the front fork equipped with a contraction motion regulating means for regulating motion and a disc brake device for braking the front wheels, a caliper is swingably supported on the front axle, and A connecting rod is provided on a protruding piece protruding from the back surface of the bottom case at an outer position so as to be able to swing freely in the longitudinal direction of the vehicle body, and a shaft cylinder having an eccentric shaft hole is connected between the intermediate portion of the connecting rod and the caliper. Preventing the front part of a vehicle body of a small vehicle from sinking, characterized in that the connecting rod is swingably connected to the caliper through a shaft member, and the tip of the connecting rod is connected to the operating part of the contraction motion regulating means. Device.