JPS642963Y2 - - Google Patents

Description

[Detailed explanation of the idea]

The present invention relates to a device for preventing vibration of a control cable that transmits operating force by tension. For example, when connecting a car's clutch pedal and clutch operating lever using a control cable, if the end of the cable is directly connected to the lever,
Engine vibrations are transmitted to the pedals via the cables, causing discomfort to the driver. Conventionally, as a preventive measure, the terminal of the control cable a made of twisted wires is connected to the bottom plate, as shown in Figure 1. It is inserted into the center hole d of a cylindrical synthetic rubber elastic body c that is tightly fitted into a metal protection cylinder b, and the protruding end thereof is passed through the backing plate f to fix the metal fitting e. The part of the cable a that protrudes from the protection tube b is fitted into the groove j on the bottom of the connector i connected to the lever g for clutch operation with a pin h, and by applying spring force to the lever g, the backing plate f is moved. The elastic body c and the bottom plate of the protective tube b are brought into contact with the bottom surface of the connector i, respectively, so that relative movement is caused between the cable a and the connector i by compression of the elastic body c, The vibration of the control cable a is absorbed by the elasticity of the elastic body c, and the protection tube b prevents the elastic body c from being abnormally deformed or damaged, thereby improving its durability. In such a device, when the control cable a is pulled and a compressive load is applied to the elastic body c, the outer periphery of the elastic body c is restrained by the protective tube b. Since the radial expansion due to axial compression is prevented, the load P/deflection δ characteristic is such that the spring constant increases as the load P increases, as shown by characteristic curve B in Figure 3. When the load rapidly increases and reaches a constant load Pa, the characteristic is such that no deflection δ occurs, and the constant load
In a high load region of Pa or more, the elastic body c loses its elasticity, and there was a problem in that it could not perform the vibration isolation function. Incidentally, such a situation also occurs when the vibration isolator is provided on the clutch pedal side, or when it is applied to a control cable for other purposes. The present invention has been developed in view of the above points, and is a control system that exhibits excellent vibration isolation performance even when the tensile force of the control cable increases, and that does not impair the durability of the elastic body. The purpose of this is to provide a cable vibration isolator, in which the terminal of a control cable that transmits operating force by tension is inserted into an insertion hole provided in a mating member, and a metal fitting fixed to the terminal of the cable is connected to the mating member. Between,
The main feature is that an elastic body made of synthetic resin mixed with 50 to 90% by weight of ferrite powder is inserted, and the elastic body made of synthetic resin mixed with ferrite powder has appropriate rigidity. Therefore, even if high loads are applied, there will be no abnormal deformation or damage.
In addition, it has excellent durability, and unlike conventional devices, it is fitted externally to the elastic body to increase the durability of the elastic body and to prevent the stroke from increasing abnormally when the tensile force of the control cable increases. This eliminates the need for a metal protective tube that restricts the elastic deformation of the elastic body, resulting in weight reduction.In addition, even when a high load is applied to the elastic body, the protective tube prevents its elasticity, unlike conventional methods. Deformation is not restricted, moderate elasticity is maintained over a wide range of load areas, and vibrations of the control cable are effectively absorbed. Hereinafter, a preferred embodiment of the vibration isolating device of the present invention will be explained with reference to FIGS. 2 and 3.
As shown in the figure, the terminal of the control cable a consisting of stranded wires is made of an elastic body made of a composite material made of epoxy resin mixed with 85% by weight of ferrite powder represented by FeO.Fe ₂ O ₃ and molded into a cylindrical shape. A connector i is inserted into the center hole d of the cable 1, and its protruding end is passed through the backing plate f to fix the metal fitting e, and the part of the cable a that protrudes from the elastic body 1 is connected to the lever g with a pin h. By fitting the elastic body 1 into the groove j on the bottom surface and applying a spring force to the lever g, a structure is created in which both ends of the elastic body 1 are held between the patch plate f and the bottom surface of the connector i, and the elastic body 1 The vibrations of the control cable are absorbed.
Since the elastic body 1 is not fitted into the protective tube b as shown in Fig. 1, even when the tensile force of the control cable a increases and a large compressive load is applied to the elastic body 1, the As shown in FIG. Elastic body c shown in the figure
Even in high load areas where elasticity is lost,
The elastic body 1 of this example can maintain appropriate elasticity, and is given appropriate rigidity by mixing FeO・Ee ₂ O ₃ powder, so it will not be abnormally deformed or damaged. It has excellent durability. Next, we will compare the performance of the vibration isolator of this example with the conventional device with a protective tube in which the synthetic rubber elastic body c shown in FIG. Conventional without a protective tube that does not fit into the protective tube B

[Table] In this table, the elastic deformation strain represents the strain in the axial direction of each elastic body when the control cable a is pulled with a force of 50 kg, which is the maximum value in the load range where vibration isolation effect is required. The strain of the elastic body 1 of the embodiment is suppressed to a slightly larger degree than the strain of the elastic body c of the conventional device with a protective tube, and the cable a is under the maximum load.
This shows that the stroke of cable a does not increase abnormally even when pulled at 50 kg, unlike the conventional device without a protective tube. It shows the number of times each elastic body can be repeated until it breaks when the pulling action is repeated. Elastic body c of the conventional device without a protective tube broke after 50,000 times or less, whereas the conventional device with a protective tube broke. Similar to the elastic body c of the device, the elastic body 1 of this example fully satisfies the durability standard of 1 million cycles, and furthermore, the permanent deformation strain that occurred after this durability test was lower than that of the conventional device with a protective tube. It is clear that the elastic body 1 of this example has sufficient durability for practical use even without the protective tube b. Regarding the anti-vibration function, conventional equipment with a protective tube can handle loads.
If the load exceeds 30 kg, the function is lost, but the device of this example, like the conventional device without a protective tube, functions satisfactorily over the entire load range from no load to the maximum load of 50 kg. It was confirmed that In addition, as described above, the elastic body 1 according to this embodiment contains 85% by weight of FeO.Fe ₂ O ₃ in the epoxy resin.
The raw material is a composite material mixed with powder, but instead of epoxy resin, phenol resin,
Using other synthetic resins such as melamine resin, and using MgO・Fe ₂ O ₃ instead of FeO・Fe ₂ O ₃ ,
Other ferrites such as ZnO.Fe ₂ O ₃ and CuO.Fe ₂ O ₃ may also be used. If the proportion of ferrite powder in the composite material is too large, the resulting elastic body will have high rigidity and excellent durability, but its elasticity will decrease.
On the other hand, if it is too small, the elasticity will be excellent but the durability will be reduced, so the ratio is preferably 50 to 90%.
In particular, it has been confirmed through experiments that 80 to 90% is more preferable.

[Brief explanation of the drawing]

Figure 1 is a sectional view of a conventional vibration isolator, Figure 2a is a sectional view of an embodiment of the present invention, b is a sectional view under high load, and Figure 3 is a load-deflection characteristic diagram. be. 1: Elastic body, a: Control cable, e:
Metal fitting, i: mating member, j: insertion hole.

Claims (1)

[Scope of utility model registration request] The end of a control cable that transmits operating force by tension is inserted into an insertion hole provided in a mating member, and 50 to 90% by weight ferrite powder is inserted between the metal fitting fixed to the end of the cable and the mating member. A control cable vibration isolation device characterized by interposing an elastic body made of mixed synthetic resin.