JPS61144407A - Frictional locking device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a friction lock device using a coil spring.

[Conventional technology]

Conventionally, due to the frictional force of a coil spring wrapped around a rod,
Friction locking devices are known that are capable of locking the axial movement of a rod. In this type of locking device, in order to lock the rod in both axial directions, two coil springs are generally arranged in series, as disclosed in Japanese Patent Publication No. 56-27733. was needed.

Therefore, the present applicant has provided a friction locking device as typified by Japanese Utility Model Application Laid-Open No. 58-24505 in order to enable locking in both directions with one coil spring.

In this prior art, as shown in FIG. 5, a rod 2 is inserted through a cylindrical body 1 that is open at both ends so as to be relatively movable in the axial direction. Furthermore, a pair of bearing members 3.4 are fixed within the cylindrical main body, and inner end surfaces 7, 8 are formed on these bearing members 3, 4 at an angle with respect to the axis of the coil spring 5. Further, a rotating member 9 is housed within the cylindrical body 1. One end 5a of the coil spring 5 is connected to a rotating member 9.
The other end portion 5b of the coil spring is locked to a locking portion 11 formed on the bearing member 4.

Thus, in this friction lock device, when the operator 12 interlocked with the rotating member 9 is moved in the unwinding direction of the coil spring 5, the rod 2 becomes movable in the axial direction due to the expansion of the inner diameter of the coil spring 5.

On the other hand, when the operator 12 is released, the inner peripheral surface of the coil spring 5 comes into close contact with the rod 2. When an external force in the axial direction is applied to the rod 2 in this state, the end surface of the coil spring 5 is pressed against the inner end surface 7 or 8) located in the moving direction of the rod 2. In this way, a force is generated that bends the coil spring 5 to an angle greater than the natural helical angle, and the rod 2 is firmly locked. According to this structure, only one coil spring is needed, so the structure can be simplified.

[Problems with conventional technology]

In the above prior art, for example, when a force is applied to the rod 2 in the right direction in the figure, the coil spring 5
It is pressed and locked. In this case, since the coil spring 5 tends to move away from the left bearing member 3, the rotating member 9 can be smoothly rotated in the unlocking direction.

However, contrary to the above, when a force pushing the rod 2 to the left is applied, the coil spring 5 is pressed against the left bearing member 3, and a large frictional force is generated between the left end of the coil spring 5 and the bearing member 3. . Therefore, a large force is required to rotate the rotating member 9 in the unlocking direction against the frictional force. For this reason, the strength of the operator 12 must be set quite high. Furthermore, even if a structure is adopted in which the coil spring 5 is integrated with the bearing member 3 and rotated by the operator 12, frictional resistance is generated between the bearing member 3 and the other surface that receives the bearing member 3. As a result, unlocking requires a lot of force.

[Means for solving problems]

The friction lock device of the present invention includes a cylindrical body that is open at both ends, a rod that is inserted through the cylindrical body so as to be relatively movable in the axial direction, and a rod that is wound around the outer periphery of the rod in the cylindrical body and that is wound at both ends. a coil spring each having a locking portion, a pair of rotatable bearing members located at both ends of the coil spring, and a pair of rotatable bearing members provided on each of these bearing members and protruding outside the cylindrical body. and an operator.

The bearing members are each housed in the cylindrical body, are rotatable relative to the cylindrical body, are restricted in movement in the axial direction, and have inner end surfaces inclined with respect to the axis of the coil spring. Both end locking portions of the coil spring are locked to these bearing members.

[Effect]

In the friction lock device configured as described above, the inner diameter of the coil spring is expanded and the lock can be released by relatively rotating the operating element provided on each bearing member in the unwinding direction of the coil spring. Conversely, when the inner circumferential surface of the coil spring comes into close contact with the rod, a locked state is achieved. In this locked state, when an axial force is applied to the rod, the end surface of the coil spring is pressed against the inclined inner end surface of the bearing member, so that the coil spring tightens the rod even more strongly.

Each bearing member is rotatable with respect to the cylindrical body and the rod, so even if the rod is pushed in any axial direction, at least one of the bearing members will move in the unlocking direction. Can rotate smoothly. Therefore, the movement of the operator is extremely smooth regardless of the direction or magnitude of the force.

(Embodiment) In one embodiment shown in FIGS. 1 to 3, the cylindrical main body 15 is open at both ends.
A pair of through windows 16. are spaced apart in the axial direction in the side walls of the .
17 is formed.

A rod 20 is inserted through the cylindrical main body 15 so as to be relatively movable in the axial direction. The cross section of this rod 20 is circular.

Further, one coil spring 23 is housed inside the cylindrical main body 15. This coil spring 23 is wound around the outer circumference of the rod 20, and the inner diameter of the coil is slightly smaller than the outer diameter of the rod 20. Therefore, in the free state, the rod 20
The coil spring 23 is in close contact with. At both ends of the coil spring 23, locking portions 25 and 26 are provided that protrude in the radial direction, respectively.

A pair of bearing members 30 and 31 are provided at both ends of the coil spring 23. Each of the bearing members 30, 31 has a substantially cylindrical shape, is housed inside the cylindrical body 15 with the rod 20 inserted therethrough, and is rotatable relative to the cylindrical body 15, while being movable in the axial direction. is limited. Further, the bearing member 30.31 is formed with an inner end surface 33.34 inclined with respect to the axial direction of the coil spring 23, and an engaging portion 36 for fitting the both end locking portions 25.26 of the coil spring. .37 is formed.

Further, a fixing ring 39 is fixed to the cylindrical body 15 at the outer end side of one of the bearing members 30 .

Furthermore, each bearing member 30.31 is provided with an operator 41.42. The operating elements 41.42 project outwardly from the through-holes 16.17. The mutual opening angle of the operators 41 and 42 is, for example, about 30" to 45 degrees, but it is of course possible to have an angle other than that. The slits 45 and 46 formed in the cylindrical main body 15 are Operator 41 during assembly
．． 42.

In one embodiment of the device having the above configuration, when the operating elements 41 and 42 are in the unlocked state as shown in FIG. be close

In this state, if a downward force is applied to the rod 20, the coil spring 23 will be pressed against the lower bearing member 31 and will be warped along the inclined inner end surface 34 beyond the natural helical angle of the coil. As a result, the rod 20 comes into closer contact with the rod 20, and the rod 20 is firmly locked. Conversely, when the rod 20 is pushed upward, it is pressed against the inclined inner end surface 33 of the upper bearing member 30, and is locked for the same reason as above.

Further, when the operating elements 41 and 42 are rotated in a direction toward each other, the coil spring 23 is twisted in the unwinding direction, that is, in the direction in which the inner diameter is expanded. Therefore, the frictional force on the rod 20 is reduced or canceled, and the rod 20 becomes movable in either the up or down direction.

According to the above configuration, the pair of upper and lower bearing members 30°
31 is rotatable with respect to the cylindrical body 15 and the rod 20. Therefore, when the rod 20 is in the locked state, the rod 20 is pushed in the axial direction, and the coil spring 23 is activated by one of the bearing members 30 (
or 31), the opposite bearing member 31 (or 30) can smoothly rotate in the unlocking direction.

Therefore, it is not necessary to require excessive force to drive the operating elements 41, 42, or to make the operating elements 41, 42 stronger than necessary.

FIG. 4 shows an example in which the friction lock device described above is applied to an on/off switching device for a vehicle stabilizer.

That is, a friction lock device having a structure similar to that described above is provided between the end of the arm portion 50 of the stabilizer and the member 51 on the vehicle body side. Then, by remote control, the operator 41.
42 to lock and unlock the rod 20, the member 51 on the vehicle body side and the arm portion 50
relative movement is allowed or restricted, and the stabilizer effect can be turned on or off.

While the vehicle is running, the arm portion 50 frequently moves up and down relative to the vehicle body member 51 due to unevenness or curves in the road surface. That is, the rod portion 20 frequently moves up and down with respect to the cylindrical main body 15.

Therefore, if the friction lock device of the present invention is used, when force is applied to the rod 20 in both the up and down directions, as in the case of such a stabilizer on/off switching device, the operator 41.
2 can now be driven smoothly, which is extremely effective. However, the present invention is not limited to use in stabilizers, but can be highly effective in locking various devices in which force is applied to the rod in both directions.

〔Effect of the invention〕

According to the present invention, not only can a single coil spring be used to exert a locking force against forces in both directions of the rod, but also regardless of the direction in which the rod is pushed or the magnitude of the pushing force.
The lock can be smoothly released.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a friction lock device showing an embodiment of the present invention, FIG. 2 is a sectional view of the friction lock device shown in FIG. 1, and FIG. 3 is a friction lock shown in FIG. 1. FIG. 4 is an exploded perspective view of the device, FIG. 4 is a side view showing an example of use of the friction lock device of the present invention, and FIG. 5 is a sectional view showing a conventional friction lock device. 15... Cylindrical body, 20... Rod, 23... Coil spring, 25.26... Locking part, 30.31...
Bearing member, 33.34... Slanted inner end surface, 41.4
2...Manipulator. Applicant's agent Patent attorney Takehiko Suzue Figure 2 Figure 1 Figure 3

Claims (1)

[Scope of Claims] A cylindrical body with both ends open; a rod inserted through the cylindrical body so as to be relatively movable in the axial direction; a coil spring having a locking portion; and a coil spring located at both ends of the coil spring, housed in a cylindrical body, rotatable relative to the cylindrical body, and having limited movement in the axial direction; a pair of bearing members each having an inner end surface inclined with respect to the axis of the coil spring and to which both end locking portions of the coil spring are locked; A friction lock device comprising a pair of protruding operators.