JPH0330896Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Field of Application> The present invention relates to a pedal depression force reduction mechanism for a clutch or the like.

<Prior Art> Conventionally, as shown in FIGS. 3 and 4, a pedal lever 2 is mounted on a bracket 10 on which a master cylinder 1 is fixed, and a pedal lever 2 is rotatable by a shaft 3, as shown in FIGS. 3 and 4. A link lever 5 that supports the pedal lever 2 and rotates together with the pedal lever 2 is fixed to the shaft 3, and the link lever 5 and the master cylinder 1 are connected to each other.
It had a structure in which the push rod 6 was connected by a pin 8.

<Problems to be solved by the invention> In the conventional mechanism described above, the movement of the pedal lever 2 is transmitted to the push rod 6 via the link lever 5, so the pedal depression force is equal to the initial force as shown by curve A in Fig. 5. It was getting heavy from an early point on.

<Means for solving the problems> The present invention solves the above-mentioned conventional problems.The upper end of the pedal lever is rotatably supported by a shaft on a bracket to which a master cylinder is fixed, and this pedal lever and In a pedal connected to a push rod of a master cylinder, a guide roller is provided on the bracket to support the push rod while allowing the push rod to move forward and backward, and a link lever is fixed to the shaft of the pedal lever so as to be rotatable together with the pedal lever. , this link lever and push rod are connected by a link.

<Operation> In this invention, when the pedal lever is depressed, the link lever rotates around the axis and pulls the link, and the push rod is moved forward on the guide roller.
Operate the master cylinder.

<Example> An example of the present invention will be described below based on FIGS. 1 and 2. Reference numeral 1 designates a master cylinder, which is fixed to the bracket 10. Reference numeral 2 denotes a pedal lever, which is rotatably supported on the bracket 10 by a shaft 3. This invention is based on bracket 1.
0 is provided with a guide roller 7 that supports the push rod 6 of the master cylinder 1 while allowing the push rod 6 to move forward and backward, and the push rod 6 and the link lever 5 fixed to the shaft 3 so as to be rotatable together with the pedal lever 2. They are connected by pins 8 and 9 via a link 4.

Since the present invention has the structure as described above, when the pedal lever 2 is depressed, the link lever 5 is moved to the shaft 3.
rotate around. This rotation of the link lever 5 pulls the link 4, moves the push rod 6 forward and backward on the guide roller 7, and the master cylinder 1
operate.

The pedal depression force reduction mechanism of the present invention that performs such an operation can be obtained from the following equation since the amount of pedal work is constant. In Fig. 6, R: length of pedal lever, r: length of link lever, f: reaction force of master cylinder, l: length of link, θ: link lever angle, S: horizontal length of link, a : Assuming the vertical length of the link, the pedal depression force F is F=r/Rf{S/l ₂ (Scosθ−asinθ)}(a), and by taking l, S, a, and θ appropriately, the pedal force F is the same as the conventional one. Regarding the amount of pedal depression, the pedal depression force can be reduced by formula (A) above, and B in Figure 5
As shown by the curve, the pedal force can be significantly reduced from the beginning of the full pedal stroke to just before the end, compared to the conventional curve A.

<Effects of the invention> As described above, according to the invention, in a pedal in which the upper end of the pedal lever is rotatably supported by a shaft on a bracket to which a master cylinder is fixed, and the pedal lever and the push rod of the master cylinder are connected, A guide roller is provided on the bracket to support the push rod while allowing the forward and backward movement direction of the push rod, a link lever is fixed to the shaft of the pedal lever so as to be rotatable together with the pedal lever, and the link lever and the push rod are connected by a link. Because of this structure, the lever ratio of the link lever in the conventional mechanism is increased, and by a simple mechanism that connects this link lever and the push rod of the master cylinder with a link, the pedal depression force can be greatly increased from the beginning of pedal depression to just before the final pedal depression. can be reduced to

In addition, because the link lever and the push rod of the master cylinder are connected by a link, even if the lever ratio of the link lever is increased, the shaft fulcrum at the upper end of the pedal lever or the push rod of the master cylinder cannot be moved.

[Brief explanation of the drawing]

Figure 1 is a side view of the present invention, Figure 2 is a view in the direction of the arrow in Figure 1, Figure 3 is a side view of the conventional mechanism, and Figure 4 is the
5 is a comparison curve of the pedal force of the present invention and the conventional mechanism, and FIG. 6 is a diagram for creating a formula for calculating the pedal force of the present invention. 1... Master cylinder, 2... Pedal lever,
3...shaft, 4...link, 5...link lever,
6... Push rod, 7... Guide roller, 1
0...Bracket.

Claims (1)

[Scope of utility model registration request] The upper end of the pedal lever is rotatably supported by a shaft on a bracket to which a master cylinder is fixed, and in a pedal where this pedal lever and the push rod of the master cylinder are connected, the push rod is supported on the bracket while allowing the forward and backward movement direction of the axis. The pedal depression force reducing mechanism is provided with a guide roller that rotates the pedal lever, a link lever is fixed to the shaft of the pedal lever so as to be rotatable together with the pedal lever, and the link lever and the push rod are connected by a link.