JPS639773Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for preventing an excessive load from being applied at the final stage of the operating stroke of a control cable that transmits operating force by pulling.

For example, when connecting a car's carburetor and accelerator pedal with a control cable, if the end of the cable is directly connected to the pedal, the pedal pressure will suddenly increase at the final stage of the pedal stroke, causing serious problems such as deforming the operating shaft of the carburetor. In addition, engine vibrations may be transmitted to the pedals, causing discomfort to the driver. Therefore, it is recommended to insert a rubber elastic body between the metal fitting fixed to the end of the cable and the pedal. The elastic body prevents a sudden increase in pedal force at the final stage of the pedal stroke and absorbs vibrations. It has a thick-walled cylindrical shape with transparent holes, and the load-deflection characteristics are approximately linear, so a considerable amount of deflection occurs even in the normal operating range at low loads, leaving little compression allowance at the final stage of the pedal stroke. ,
If it is not possible to sufficiently prevent a sudden increase in pedal force, and if the pressure surfaces at both ends of the elastic body are no longer parallel as the pedal swings, the elastic body may undergo irregular deformation. This has the disadvantage that the load-deflection characteristics become unstable.

Incidentally, such a situation also occurs in overload prevention devices for control cables for other uses as well.

The present invention aims to eliminate such drawbacks.

An embodiment of the present invention will be described below with reference to the accompanying drawings.

The support shaft 3 is pressed by pressing the treading part 2 at the lower end.
A bracket 4 is fixed to the upper side surface of the pedal 1 which rotates counterclockwise about the center of the pedal 1. A seat plate 7 made of synthetic resin, an elastic body 14 made of synthetic rubber, and backing plates 10 and 11 made of metal and synthetic rubber are attached to the bracket 4 fixed to the upper side surface of the pedal 1 which rotates counterclockwise around the pedal 1. A metal fitting 13 fixed to the end of a control cable 12 made of twisted wires is in contact with a synthetic rubber backing plate 11, and the other end of the cable 12 is connected to a driven member such as an operating part of a carburetor. connected. After fitting the seat plate 7, the elastic body 14, and the cover plates 10 and 11 to the cable 12 in this order, the metal fitting 13 is fixed with a casting or the like, and the cable 12 is
from the split groove 5 formed in the bracket 4 to the mounting hole 9.
A pair of elastic locking pieces 8, 8 protruding from one surface of the seat plate 7 are elastically contracted while being passed through the mounting hole 9 and locked to the edge of the hole by elastic restoring force.

As shown in FIG. 2, the elastic body 14 as a whole has a hollow drum shape with a swollen center in the axial direction, and inward facing flanges 15 are formed at both ends, and the center in the axial direction is in the shape of a hollow drum. An annular rib 17 with a through hole 16 through which the cable 12 is inserted substantially tightly is formed on the inner periphery of the center portion, and a groove 18 is further provided around the outer periphery of the center portion. When a compressive load is applied in the axial direction, at the beginning of the compression stroke, the cylindrical portions on both sides of the rib 17 mainly undergo compressive deformation in the axial direction, so that the rate of increase in the amount of compression as the load increases is small. , the slope of the characteristic curve becomes steep as shown in region A of the load-deflection characteristic curve in FIG. 5, and in the middle of the compression stroke, as shown in FIG. As the load is increased, the rate of increase in the amount of compression is large and the slope of the characteristic curve becomes gentle as shown in area B in Figure 5, and the deformation progresses further, causing bending deformation. As shown in Figure 4, after the flanges 15, 15 at both ends hit the rib 17, they undergo compression deformation, so the rate of increase in the amount of compression increases rapidly as the load increases, resulting in area C in Figure 5. As shown, the slope of the characteristic curve becomes steep.

Therefore, when the pedal 1 is in the normal operating range with a low load, the deflection of the elastic body 14 is in region A in FIG. However, when a driven device such as a carburetor enters the final stroke of its operating range and the load increases rapidly, the elastic body 14
enters region B in FIG. 5, and the rate of increase in the amount of compression becomes relatively large. Therefore, the rate of increase in the tensile force acting on the cable 12 is small relative to the amount of actuation of the pedal 1, and it is possible to avoid applying an excessive load to a driven device such as a carburetor. Finally, in order to enter area C in Fig. 5, the cable 12
operates substantially integrally with the pedal 1.

Also, when the pedal 1 rotates significantly around the support shaft 3, the bracket 4 and the backing plate 1 of the seat plate 7
The angle with respect to 0 and 11 becomes large, and the elastic body 14 is distortedly compressed as shown in FIG. By bending around 18, it is compressed while always maintaining a symmetrical shape, and stable load-deflection characteristics are obtained.

As specifically explained in the above embodiment,
The control cable overload prevention device of the present invention has an elastic body interposed between the metal fitting fixed to the end of the control cable that transmits the operating force by tension and the driving member or the driven member, and the compression of the elastic body In the device for preventing transmission of overload by causing relative movement between the cable and the driving member or the driven member, the elastic body has a cylindrical shape with both ends open, and has an inner periphery at the center in the axial direction. The control cable is provided with an annular rib that slidably supports the control cable, and a groove is provided around the outer periphery of the central portion corresponding to the rib, and the cable is low-load. During normal operation, the rate of increase in the amount of compression of the elastic body is small, and the followability of the driving member or driven member and the control cable is excellent.At the same time, when the load is high, the rate of increase in the amount of compression becomes large, and the rate of increase in the amount of compression of the driving member or driven member and the control cable is excellent. A large relative movement occurs between the cables, which can effectively prevent the occurrence of overload, and furthermore,
Even when the pressure acting surfaces at both ends of the elastic body are no longer parallel, the deformation is constant and stable characteristics can be achieved.

[Brief explanation of the drawing]

The accompanying drawings show an embodiment of the present invention, in which Fig. 1 is a partially cutaway perspective view showing an outline, Figs. 2 to 4 are sectional views showing the deformation sequence of the elastic body, and Fig. 5 is a load on the elastic body. - A graph showing the deflection characteristics, FIG. 6 is a cross-sectional view when the rotation angle of the pedal becomes large. 1: Pedal, 4: Bracket, 7: Seat, 1
0: Backing plate, 12: Control cable, 1
3: Metal fittings, 14: Elastic body, 15: Tsuba, 17: Rib, 18: Groove.

Claims (1)

[Scope of utility model registration request] An elastic body is interposed between the drive member or the driven member and a metal fitting fixed to the end of the control cable that transmits the operating force by tension, and the compression of the elastic body causes the cable to connect with the drive member or the driven member. In the device for preventing the transmission of overload by causing relative movement between the elastic bodies, the elastic body has a cylindrical shape with both ends open, and the control cable is slidably supported on the inner periphery of the central part in the axial direction. 1. An overload prevention device for a control cable, characterized in that the control cable has a protruding rib, and a groove is provided around the outer periphery of the central portion corresponding to the rib.