JP2000330660A - Hysteresis generator - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a hysteresis sending device capable of obtaining non-parallel hysteresis characteristics without fluctuation of frictional force and capable of downsizing. SOLUTION: A pulley 1 is rotationally biased by a torsion spring 3, a cable end 41 is locked to the pulley 1, and an inner cable 4 is wound around the pulley 1 in a direction opposite to the biasing direction. Is wound around a sliding groove 26 formed on the outer periphery of the inner casing 2 outside the pulley 1, and then pulled out of the inner casing 2. Since a frictional force is generated due to a relative displacement between the inner cable 4 and the sliding groove 26, a difference in load deflection occurs between the load applied and the reduced load on the other casing end side of the inner cable 4, resulting in a hysteresis characteristic. Is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hysteresis generator for providing a hysteresis characteristic to an operation cable, and is particularly effective for use in an electronic accelerator pedal of a motor vehicle.

[0002]

2. Description of the Related Art Conventionally, for example, in a stepping operation of an accelerator pedal of an automobile, a method of generating a hysteresis characteristic for achieving operation stability includes: (1) a method using a pull cable having a long path; ) Tokuho 6
As disclosed in JP-A--24888, a disk is sandwiched between pads or rings from both sides, and a hysteresis characteristic is generated by the frictional force between them.
(3) As seen in JP-A-9-48260,
A friction drum for generating friction is placed in the middle of the cable that is biased with one end locked by a spring, and the cable is wound.When the other end of the cable is operated, the frictional force between the groove of the friction drum and the cable causes hysteresis. There is something that causes.

[0003]

In the above-mentioned conventional device, in the above-mentioned device (1), a long cable is required and the installation volume is large. In the case of the above (2), parallel hysteresis occurs, non-parallel hysteresis characteristics cannot be obtained, and in order to generate non-parallel hysteresis, it is necessary to separately combine a cam, a spring, and the like. Becomes complicated. Further, if the friction plates between the metals are fixed, the operation becomes impossible. The above-mentioned (3) has problems such as a large variation in frictional force.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a hysteresis generator which does not vary the frictional force, can obtain non-parallel hysteresis characteristics, and can be downsized.

[0005]

According to a first aspect of the present invention, there is provided a pulley which is rotationally urged by a spring, and one end of which is locked to the pulley and which is rotated in a direction opposite to the direction of urging by the spring. A cable wound around, the other end of which is pulled out in the direction of rotation opposite to the biasing direction of the spring;
A resin casing surrounding an outer periphery of the pulley, wherein a resin groove for slidably winding the cable is formed on an extension of the cable wound around the pulley in a drawing direction. Wherein a hysteresis characteristic is generated by a frictional force caused by a relative displacement between the cable and the groove.

A second aspect of the present invention is characterized in that in the first aspect, the frictional force having the hysteresis characteristic is set according to a length of a contact portion between the cable and the resin groove. A third aspect is characterized in that in the first and second aspects, the hysteresis characteristics are non-parallel. Claim 4
Is characterized by having an idle swing mechanism for use in an electronic accelerator mechanism.

[0007]

According to the present invention, the cable has one end locked to the pulley and wound around the pulley in a direction opposite to the direction of rotation by the spring, and the other end opposite to the direction of rotation by the spring. After being pulled out in the direction of rotation, it is further slidably wound around a resin groove of a casing surrounding the pulley. Therefore, at the time of a load in which the other end of the cable is pulled by a force larger than the rotational biasing force of the spring and the frictional force with the resin groove, the cable slides while generating a frictional force in the resin groove to pull the pulley. It is rewound from the pulley while rotating. Conversely, at the time of unloading when the pulling force at the other end of the cable is reduced, the cable slides while generating a frictional force between the cable and the resin groove due to the rotational biasing force of the spring, and is wound around the pulley.

In the above operation, a frictional force is generated between the cable and the resin groove. This frictional force depends on the length of contact between the cable and the resin groove, and the frictional force when applying a load is greater than the frictional force when reducing the load. Therefore, the load characteristic of the cable end (the other end) is larger when the load is applied and smaller when the load is reduced, as compared with the characteristic due to only the bias of the spring. As a result, a hysteresis characteristic is generated in the load deflection characteristic at the cable end due to the frictional force between the cable and the resin groove, and the tension state of the cable is stabilized. Since the frictional force for generating the hysteresis is generated not by the metals but by the resin groove and the metal cable, the frictional force does not fluctuate due to the adhesion of the metals.

Further, since the magnitude of the frictional force depends on the contact length between the cable and the resin groove, an arbitrary frictional force can be obtained by setting the contact length on an arc. Therefore, if the length of contact with the cable is extended by forming a resin groove spirally on the cylindrical surface or the like, the frictional force can be easily set and the device can be prevented from being enlarged, so that the size of the device can be reduced. Can be achieved.

According to the third aspect, the hysteresis characteristics are non-parallel. Since the frictional force due to the relative displacement between the cable and the resin groove depends on the total bending angle of the portion where the relative displacement between the cable and the resin groove occurs, the bending angle on the pulley side in the resin groove and the other end of the cable By changing the bending angle of the drawing side from a certain resin groove, it is possible to give a difference between the friction force at the time of loading and the friction force at the time of unloading, thereby generating non-parallel hysteresis characteristics. be able to. According to the fourth aspect, there is provided an idle swing mechanism for use for an electronic accelerator mechanism. The other end of the cable pulled out from the pulley via the resin groove can be freely set to the length after passing through the resin groove, so the cable is connected to the bush attached to the accelerator pedal etc. The end can be locked only when the accelerator pedal is depressed, and the cable end can be unlocked from the bush when the accelerator pedal is loosened. it can. Thus, in the hysteresis generator, even if the winding of the cable by the pulley rotationally biased by the spring cannot be performed for some reason,
The return of the accelerator pedal can be secured.

[0011]

FIG. 1 shows a first embodiment of a hysteresis generator according to the present invention, which is used for an accelerator of an automobile. In FIG. 1, 1 is a pulley, 2 is an inner casing, 3 is a torsion spring, 4 is an inner cable,
5 is an outer casing. FIG. 1 (a)
As shown in FIG. 3, a hole 12 penetrating from the front to the back is formed in a portion recessed inward from the outer periphery to fit the inner cable end 41 of the inner cable 4. On the back side of the pulley 1, a projection 13 for locking a torsion spring 3 described later is provided. The pulley 1 is rotatably supported by a center shaft 10 inserted into the inner casing 2.

As shown in FIG. 1B, the inner casing 2 has a pedestal portion 21 formed inside, and a center shaft 10 for rotatably supporting the pulley 1 penetrates the center of the pedestal portion 21. The pedestal portion 21 has a two-stage structure in which two large and small cylinders each having a smaller diameter on the pulley 1 side are stacked so as not to hinder the protrusion 13 of the pulley 1 when the pulley 1 rotates. The inner casing 2 has a spring recess 22 for arranging the torsion spring 3 on the outer peripheral side of the pedestal portion 21, and further has a frame portion surrounding the torsion spring 3 and forming the outer shape of the inner casing 2. 23.

A part of the frame 23 of the inner casing 2 is an outer pedestal 24 extending from the spring recess 22 toward the outer periphery, and the outer pedestal 24 and the frame 23 are formed by a bottom 25. It is formed integrally with the pedestal 21 via the spring recess 22. A sliding groove 26 for sliding the inner cable 4 is formed in the outer peripheral pedestal portion 24. The sliding groove 26 is continuous with an inner groove 26a bent by a quarter arc in the same direction as the arc of the tangential portion of the pulley 1 with an extension of a tangent at the outer periphery of the pulley 1 as a base end. Then, it is bent by a quarter arc in the direction from the pulley 1 to the bottom 25, and has a continuous arc shape having two bending angles with the outer groove 26b toward the back surface of the bottom 25.

In the spring recess 22 of the inner casing 2,
A coil-shaped torsion spring 3 having a diameter larger than the diameter of the pulley 1 is provided, and each end of the torsion spring 3 is bent toward the center of the diameter of the torsion spring 3, and one end is a protrusion of the pulley 1. The other end is fitted into a spring fixing groove 27 formed in a cut shape from the pulley 1 side toward the pedestal 21, respectively.

The inner cable 4 is connected to the groove 1 of the pulley 1.
After the inner cable end 41 is fitted into the inner hole 12 and slightly wound around the groove 11 of the pulley 1, as shown in FIG. Is drawn out from the bottom 25 so as to be wound in the sliding groove 26.

The outer casing 5 is fitted to the outside of the inner casing 2 so as to cover the frame 23, the outer pedestal 24 and the pulley 1 of the inner casing 2, and the center shaft 10
To prevent the pulley 1 from falling off and prevent the inner cable 4 from coming off the sliding groove 26.

In the above configuration, the pulley 1, the inner casing 2, and the outer casing 5 are all made of a resin material, and are here formed of POM (polyacetal). On the other hand, the torsion spring 3 and the cable 4
A well-known metal material is used. Also, the torsion spring 3
The surface of the inner cable 4 is coated with silicone-less grease, silicone grease, or synthetic oil grease depending on the application.

In the hysteresis generator having the above configuration, the pulley 1 is driven by the torsion spring 3 as shown in FIG.
2A, the inner cable 4 is urged in the leftward rotation direction in the figure, and the inner cable 4 is wound around the pulley 1 by this urging force. On the other hand, since the inner cable 4 is disposed in the sliding groove 26, when the inner cable 4 is displaced, a frictional force is generated between the inner cable 4 and the sliding groove 26. Accordingly, when the inner cable 4 is pulled from the distal end and when the tensile force from the distal end is lost after being pulled from the distal end, the load deflection characteristic at the distal end of the inner cable 4 exhibits a hysteresis characteristic.

Here, the inner cable 4 and the sliding groove 2
The frictional force between the pulley 1 and the pulley 1 during pulling from the end of the inner cable 4
Stroke against the urging force of the torsion spring 3, the surface pressure against the sliding groove 26 increases, and the frictional force increases. Conversely, when the load on the end of the inner cable 4 is reduced, the torsion spring 3 of the pulley 1
Stroke in the direction corresponding to the urging force, the surface pressure is reduced as compared with the time of the load, and the frictional force is thereby reduced. As a result, a hysteresis phenomenon occurs in each of the frictional forces at the time of loading and unloading. In addition, by increasing or decreasing the length of contact between the inner cable 4 and the sliding groove 26 in accordance with the required hysteresis characteristics, it is possible to satisfy a desired friction performance (characteristics when loaded or unloaded). it can.

FIGS. 2 and 3 show a second embodiment of the present invention. In the second embodiment, as shown in FIG. 2A, the outer peripheral pedestal portion 24 is not provided as in the first embodiment, and the sliding groove 26 in the inner casing 2 is replaced with the frame portion 23.
Is formed so as to surround the pulley 1 in the outer peripheral portion of
The length is secured. For this reason, the thickness of the frame 23 is slightly increased. In the outer peripheral portion of the frame portion 23, the sliding groove 26 is formed of a plurality of types of continuous arcs having several bending angles. As shown, it is bent in the shape of an arc toward the bottom 25 as in the first embodiment, and is drawn out. As shown in FIG. 3, the torsion spring 3 has a diameter equal to the diameter of the pulley 1, and the overall structure is reduced by the above configuration.
With the above configuration, the sliding length between the inner cable 4 and the sliding groove 26 is longer in the second embodiment than in the first embodiment, thereby generating a large frictional force. Can be done.

An outer cable end 42 is provided at the end of the inner cable 4 drawn out of the sliding groove 26 to the outside, and the bush 6 is fitted inside the outer cable end 42 in advance. The bush 6 is mounted on the movable part of the accelerator pedal, and moves to the right in FIG. 2B when the accelerator pedal is depressed, and acts on the outer cable end 42 to move the inner cable 4 out. Let it. When the accelerator pedal is relaxed, the bush 6 moves leftward in FIG. 2B.

Here, when the accelerator pedal is depressed, the bush 6 only locks the cable end 42 and pulls out the inner cable 4 when the accelerator pedal is depressed, and is fixed to the outer cable end 42. When the accelerator pedal is released, the bush 6 is connected to the cable end 4.
2B, it can move to the left in FIG. 2B. Therefore, even when the inner cable 4 is not rewound by the pulley 1, the accelerator pedal returns together with the bush 6, and the accelerator pedal is not influenced by the behavior of the outer cable 4 by the bush 6. As described above, since the bush 6 returns together with the accelerator pedal, the behavior is irrelevant to the behavior of the outer cable end 42, and the accelerator pedal on which the bush 6 is mounted ensures an idle swing mechanism.
Therefore, even when the inner cable 4 is not rewound, the accelerator pedal can be securely returned.

FIG. 4 shows a third embodiment of the present invention. Third
In the embodiment, the pulley 1 is formed in a cylindrical shape, and the pulley 1 is
The torsion spring 3 having a diameter smaller than the diameter of the torsion spring is disposed inside the pulley 1, and both the pulley 1 and the torsion spring 3 are arranged in the spring recess 22. In the inner casing 2, the sliding groove 26 formed so as to surround the pulley 1 using the outer peripheral portion of the frame 23 is used to rotate the pulley 1 and the torsion spring 3 by one or more turns (1
(+ About three-quarters of a turn) in a spiral shape so as to surround it, and is not bent in the direction of the bottom 25. The inner cable 4 is arranged so as to be directly drawn out from the outer peripheral portion of the frame portion 23 of the inner casing 2 onto a tangent line of the frame portion 23, and the outer cable end 42 is engaged with the bush 6, and the second embodiment is described. A swing mechanism is formed in the same manner as described above.

Note that the idle swing mechanism in the outer cable end 42 shown in the second and third embodiments is completely the same in the outer cable end of the inner cable 4 in the first embodiment. It can be configured.

The inner cable 4 in the third embodiment
FIG. 5 shows the relationship between the total angle (bending angle) of the inner casing 2 wound around the sliding groove 26 and the ratio of the output load to the input load (efficiency). As shown here,
It can be seen that the efficiency is not constant, and the greater the bending angle, the lower the efficiency and the greater the difference in load at both ends of the inner cable 4.

FIG. 6 shows the relationship between the length (stroke) of the inner cable 4 and the load at the cable end in the third embodiment. The load stroke characteristic at the outer cable end 42 when the inner cable 4 is pulled out when the inner cable 4 is pulled out is more than twice as large as the load characteristic of the spring alone, and conversely, the inner cable 4 is wound by the pulley 1. The unloading load taken is
It can be seen that the load characteristic is reduced to about half of the load characteristic of the spring alone. Further, when comparing the line X indicating the load characteristic at the time of the applied load with the line Y indicating the load characteristic at the time of the unloading, the load difference between the respective lines in the same stroke is not constant.
It can be seen that they are non-parallel, and that the load deflection characteristics at the time of loading and unloading are non-parallel hysteresis characteristics.

In the above embodiment, an example of a hysteresis generating device for an accelerator pedal of an automobile has been described. However, if the operating portion requires hysteresis in the load deflection characteristic and requires operational stability, other operating parts may be used. It can be applied to any part.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of a hysteresis generator according to the present invention, wherein FIG. 1 (a) is a front sectional view showing the inside of an outer casing, and FIG. 1 (b) is a partial sectional view from the A direction of FIG. Figure,
(C) is a partial cross-sectional view from the B direction of (a).

FIGS. 2A and 2B are views showing a second embodiment of the hysteresis generator of the present invention, wherein FIG. 2A is a front sectional view, and FIG.
It is a partial sectional view from a viewing direction.

FIG. 3 is a view showing a second embodiment of the hysteresis generator of the present invention, and is a cross-sectional view taken along line DD of FIG. 2 (a).

4A and 4B are diagrams showing a third embodiment of the hysteresis generator of the present invention, wherein FIG. 4A is a front sectional view, and FIG. 4B is a sectional view along line EE.

FIG. 5 is a graph showing the relationship between the total angle (bending angle) of the inner cable wound around the sliding groove and the ratio of the output load to the input load (efficiency) in the third embodiment of the hysteresis generator of the present invention. FIG.

FIG. 6 is a drawing length (stroke) of an inner cable in a third embodiment of the hysteresis generator of the present invention.
FIG. 4 is a characteristic diagram showing a relationship between the load and the load.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pulley 2 Inner casing (resin casing) 26 Sliding groove (resin groove) 3 Torsion spring 4 Inner cable

Claims (4)

[Claims] A pulley that is rotationally biased by a spring; one end of which is locked to the pulley and is wound in a rotation direction opposite to a biasing direction of the spring; A cable drawn in the reverse rotation direction, and a resin casing surrounding the outer periphery of the pulley, the cable being slidably wound on the extension of the cable wound around the pulley in the drawing direction. A hysteresis generator comprising: a grooved casing having a resin groove formed therein for generating a hysteresis characteristic by a frictional force caused by a relative displacement between the cable and the groove. 2. The hysteresis generator according to claim 1, wherein a frictional force having the hysteresis characteristic is set according to a length of a portion where the cable and the resin groove are in contact with each other. 3. The hysteresis generator according to claim 1, wherein said hysteresis characteristics are non-parallel. 4. The hysteresis generator according to claim 1, further comprising an idle swing mechanism for use in an electronic accelerator mechanism.