JPH0432253B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a spring device that utilizes the attractive force of a magnet, and particularly to a spring device that utilizes both the restoring force of a spring and the attractive force of a magnet. The present invention relates to a spring device configured to obtain displacement-load characteristics.

<Prior Art> Conventionally, in addition to so-called linear springs in which the load or restoring force changes linearly with respect to displacement, there has been a demand for springs having various nonlinear characteristics.
The attached Figure 1 shows the basic characteristics of such springs, and the straight line A shows the characteristics of a general linear spring in which the restoring force, that is, the load P, increases proportionally to the displacement δ. , curve B shows the so-called displacement-load curve of a rigid spring in which the rate of increase in load gradually increases as the displacement increases, and curve C shows the rate of increase in load decreases as the displacement increases. This shows the characteristics of a so-called soft spring.

Disc springs are known to have the characteristics of a soft spring, while conical springs and unequal pitch springs have the characteristics of a hard spring.
Regarding soft springs in particular, if we take a disc spring as an example, in order to obtain a sufficient stroke, the diameter must become enormous or multiple pieces must be stacked, so it is not always possible to obtain the desired soft spring characteristics. I couldn't do it.

On the other hand, if an active element that utilizes hydraulic pressure or electromagnetic force is used, it is possible to realize a free displacement-load characteristic, but the device becomes large-scale and its applications are severely limited.

On the other hand, as a spring device that uses a magnet, there is a known spring device that uses the repulsive force of a magnet, such as the one disclosed in Japanese Patent Application Laid-Open No. 53-84545, but since it uses only a magnet, Not only can the characteristics not be freely set, but it also has the disadvantage that it is difficult to take a sufficiently large stroke compared to springs.

<Problems to be Solved by the Invention> In view of the shortcomings of the prior art, the main object of the present invention is to provide a spring device that is configured such that the displacement-load characteristics of a soft spring can be set freely. It is about providing.

<Means for solving the problem> According to the present invention, this purpose is achieved by using a spring and
A pair of magnets connected to each end of the spring with different poles facing each other, or a magnet and a magnetic body connected to each end of the spring, the pair of magnets being connected to each end of the spring with different poles facing each other. A spring device using a magnet, characterized in that the pair of magnets or the magnet and the magnetic body are arranged so that the attractive force between the magnet and the magnetic body is increased. This is achieved by providing

<Function> According to such a configuration, the magnets or the magnet and the magnetic body are arranged so that the distance between them becomes narrower according to the displacement of the spring. Due to the influence of the attractive force of the magnet, which increases according to the square law, it is possible to obtain an effect as if the spring constant of the spring were decreased in accordance with the amount of displacement. That is, a displacement-load characteristic is obtained that is a combination of the restoring force characteristic of the spring and the attractive force characteristic of the magnet. In particular, if known soft springs and other non-linear springs are used in combination, a wider range of displacement-load characteristics can be achieved, such as properties similar to those of a constant-load spring where the restoring force against displacement, that is, the load hardly changes. be able to.

<Examples> Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 shows an embodiment in which the present invention is applied to a compression coil spring, in which two permanent magnets 1 and 2, which face each other and have substantially complementary conical surfaces, are connected to each other. , 2, the guide shaft 3 is inserted through holes 1a and 2a drilled in the centers of the guide shafts 3 and 2, respectively.
They are arranged so as to be able to approach and separate from each other in the axial direction. As shown in the figure, both magnets 1 and 2 are magnetized so as to have magnetic pole arrangements that attract each other along the axial direction.

Outward flanges 1b and 2b are integrally provided around the outer ends of both of these magnets 1 and 2, respectively.
A compression coil spring 5 is sandwiched between these flanges 1a and 1b. The flange 4 provided on the guide shaft 3 is for preventing the magnets 1 and 2 from coming too close to each other, and when the compression coil spring 5 is in close contact with the magnets 1 and 2, This flange 4 can be omitted if the required distance can be secured.

According to this embodiment, as the compression coil spring 5 is compressed, both the magnets 1 and 2 approach each other, and the attractive force between them increases in a substantially quadratic manner. For this purpose, the linear spring characteristics of the compression coil spring 5 and the attractive force characteristics of the permanent magnet are combined, and a displacement-load characteristic that cannot be obtained with a general coil spring, as shown by the solid line in Fig. 10, is obtained. .

3 and 4 show another embodiment in which the present invention is applied to a torsion spring. 2 permanent magnets 2
1 and 22 are holes 21b and 22b coaxially drilled at the center positions of both magnets 21 and 22, respectively.
The surfaces 21c and 22 are configured to be able to rotate relative to each other around a guide shaft 23 that is inserted through the axis of rotation, and surfaces 21c and 22 that are inclined with respect to a surface perpendicular to the axis of rotation, respectively.
The magnetic poles are arranged so as to face each other with different magnetic poles. Also, a pair of outward flanges 24, 2 provided on the guide shaft 23
5, the relative position between these two magnets 21 and 22 along the axial direction is kept constant. A torsion coil spring 27 is provided on the outer periphery of both of these magnets 21 and 22.
is wound around each end 2 of the torsion coil spring.
7a and 27b are respectively locked in slots 21a and 22a cut in the outer ends of both magnets 21 and 22 in portions that protrude outward in the radial direction.

Mutual opposing surfaces 21 of these magnets 21 and 22
Since the protrusions c and 22c are each tapered, a suction force is constantly applied to bring the protrusions of the opposing surfaces 21c and 22c closer to each other. Therefore, when the torsion spring 27 is in the neutral position,
As shown in FIG. 3, both opposing surfaces 21c, 2
When the portions of magnets 2c protruding into the magnetic gap 26 are at opposite diagonal positions, both magnets 21 and 22
Since the attractive force in the torsional direction between the two increases as the angular displacement of the torsion spring 27 increases, a displacement-load characteristic corresponding to the characteristic curve shown in FIG. 10 is obtained.

5 to 8 show still another embodiment in which the present invention is applied to a torsion spring. Two permanent magnets 32 and 34, each having a substantially rectangular parallelepiped shape, are embedded in synthetic resin cylinders 31 and 33, respectively, and are supported by a common guide shaft 35 so as to be rotatable coaxially with each other. Both magnets 32 and 34 are connected to the guide shaft 35
An outward flange 36 provided at the center of the two allows them to rotate relative to each other while maintaining an equal distance from each other.

As shown well in Figures 7 and 8,
Both of these magnets 32 and 34 have longitudinal end surfaces in the diametrical direction and face each other in directions perpendicular to each other.
Both of these magnets 32 and 34 exert an attractive force on each other that tends to twist them toward mutually aligned positions. Further, a torsion coil spring 38 is wound around the outer periphery of both cylindrical bodies 31 and 33, and each end of the torsion coil spring 38 is
Slots 31 are cut in the outer ends of both cylindrical bodies 31 and 33, respectively, in portions that protrude outward in the radial direction.
a, 32a.

In this embodiment, as in the previous embodiment, when the torsion coil spring 38 is in the neutral position, both the magnets 32, 3
When the opposing end surfaces of No. 4 are disposed in substantially orthogonal directions, a displacement-load characteristic corresponding to the characteristic curve of FIG. 10 is obtained.

FIG. 9 shows an embodiment in which the present invention is applied to a nonlinear spring. A flat ring-shaped permanent magnet 43 is fitted in a bottomed cylindrical casing 41, and a spacer 4 is placed on the upper surface of the permanent magnet 43.
A disc spring 45 made of a magnetic material is placed through the spring 4 . The upper end of the casing 41 is closed by a cover plate 42 having a circular center hole. Further, a shaft portion 46 having a flange 47 at the upper end is attached to the disc spring 4.
It passes through the center hole of the magnet 43 and is loosely fitted into the center hole of the magnet 43. Further, the flange 47 of the shaft portion 46 is also adapted to be able to protrude into the center hole of the cover plate 42.

The disc spring 45 generally has the tendency of a soft spring as shown by curve C in FIG. It has the characteristics that it has. Therefore, when the flange portion 47 is displaced downward, the attraction force of the permanent magnet 43 to the disc spring 45 increases, so that the tendency of the disc spring 45 to act as a soft spring is further strengthened, and the disc spring 4
By increasing the deflection of 5, it is possible to realize spring characteristics in which the spring constant takes a significantly negative value.

In addition, when using a non-magnetic material as the disk spring 45, if a flat ring-shaped iron piece 48 is fixed to the lower surface of the flange portion 47, the same effect as described above can be obtained, and the spacer 44 can be omitted. I can do it.

Although the present invention has been described above with reference to specific embodiments, it is possible to implement the present invention with various modifications and changes without departing from the concept of the present invention. In fact, the present invention can be applied in various ways by appropriately adding permanent magnets to leaf springs, torsion bars, and other types of springs.

<Effects of the Invention> As described above, according to the present invention, by using only passive elements, that is, springs and magnets, the rate of increase in load in response to an increase in displacement is extremely small, or even reduced. Since it is possible to realize a displacement-load characteristic that is suitable for spring devices, it is possible to apply it to devices that balance gravity or devices that want to keep the reaction force against a stroke approximately constant. It is possible to achieve the effect that various engineering demands can be easily and suitably satisfied.

[Brief explanation of drawings]

FIG. 1 is a graph showing basic types of spring displacement-load characteristics. FIG. 2 is a longitudinal sectional view showing an embodiment in which the present invention is applied to a compression coil spring. FIG. 3 is a longitudinal sectional view showing an embodiment in which the present invention is applied to a torsion spring. Figure 4 is - of Figure 3.
FIG. 3 is an end view of the line; FIG. 5 is a longitudinal sectional view showing still another embodiment in which the present invention is applied to a torsion spring. 6 is an end view taken along the - line in FIG. 5. FIG. 7 and 8 are cross-sectional views taken along the - line and - line of FIG. 5, respectively. FIG. 9 is a longitudinal sectional view showing an embodiment in which the present invention is applied to a nonlinear spring. 10th
The figure is a graph conceptually showing an example of the displacement-load characteristic curve of the present invention. 1, 2... Magnet, 1a, 2a... Hole, 1b, 2
b...Flange, 3...Guide shaft, 4...Flange, 5...Compression coil spring, 21, 22...Permanent magnet, 21a, 22a...Slot, 21b, 2
2b... Hole, 21c, 22c... Opposing surface, 23...
...Guide shaft, 24, 25...Flange, 26...
Between, 27...Torsion coil spring, 27a, 27b
...End, 31, 33...Cylindrical body, 31a, 32
a...Slot, 32, 34...Permanent magnet, 35
... Guide shaft, 36 ... Flange, 37 ... Interval, 38 ... Torsion coil spring, 41 ... Casing, 42 ... Cover plate, 43 ... Permanent magnet, 44 ...
Spacer, 45... Belleville spring, 46... Shaft, 47
...flange, 48...iron piece.

Claims (1)

[Scope of Claims] 1. Consisting of a spring and a pair of magnets connected to each end of the spring with different poles facing each other, or a magnet and a magnetic body connected to each end of the spring, the spring The pair of magnets or the magnet and the magnetic body are arranged such that the attractive force between the pair of magnets or the magnet and the magnetic body increases as the amount of displacement increases. A spring device using a magnet, which is characterized by: 2. The magnets are composed of two magnets that are arranged at each end of a compression coil spring so that they face each other with substantially complementary conical surfaces and can move toward and away from each other along approximately the same axis. A spring device using a magnet according to claim 1. 3. The spring is a torsion spring, and the magnet is
The torsion springs face each other with surfaces that are inclined with respect to a plane perpendicular to the rotation center line of the torsion spring, and are relatively rotatable around the rotation center line of the torsion spring. It is characterized by comprising two magnets arranged so that they cannot be relatively displaced along the center line of rotation, and placed so that their opposing surfaces are substantially parallel when the torsion spring is in a neutral state. A spring device using a magnet according to claim 1. 4. The spring is a torsion spring, and the magnet is
facing each other with end surfaces extending in a diametrical direction with respect to the rotational center line of the torsion spring;
The torsion spring is arranged such that it can be relatively rotated around the rotation center line of the torsion spring, but cannot be relatively displaced along the rotation center line of the torsion spring, and the maximum effective displacement of the torsion spring is 2. A spring device using magnets according to claim 1, characterized in that the spring device comprises two magnets placed so that their opposing surfaces face each other.