JPH01203708A - Spring device - Google Patents

Abstract

PURPOSE:To provide negative or constant load characteristics throughout the whole moving range of a moving member and to enlarge an application range, by a method wherein a device is provided with a spring, a limit member for the actuation range of the spring, and a moving member between the limit members, and the one of the limit member and the moving member is formed with a magnet. CONSTITUTION:A spring 1 is mounted to a limit member 2 formed with a spring support seat 6 making contact with a stationary base 5, a shaft 7, and a stopper plate 8. Meanwhile, a moving member 3 is formed with a head part 9, which is coupled to a pressurizing body 13 and in which the stopper plate 8 is inserted, and a leg part 10. An electromagnet 11 is mounted between the inner and the outer pipe of the leg part 10, and a magnetic attraction force is exerted between the limit member 2 and the moving member 3. A detecting means 4 is situated along a shaft 7 to detect the moving position and the moving speed of the moving member 3, and the magnetic force of the electromagnet 11 is regulated by a control means 20. This constitution provides negative or constant load characteristics throughout the whole moving range of the moving member 3, enables variation of characteristics, and allows enlargement of an application range.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a spring device that embodies properties other than the positive properties of a spring.

[Prior art and its problems] Generally, the relationship between spring load and deflection is expressed by a spring constant. With some exceptions, this spring constant has a positive characteristic in that as the deflection increases, the load also increases, and springs are assembled into various industrial equipment by taking advantage of this positive characteristic. The negative characteristic, that is, the characteristic that the load decreases as the deflection increases, cannot be obtained by a spring alone, and it has been impossible to embody the negative characteristic and put it to industrial use. However, in springs with countersunk or snap action, negative characteristics occur within a very limited range of the entire operating stroke, but this range is not only narrow, but also when used beyond the range. If this is the case, the spring will not return to its original state, so it cannot be used for practical engraving purposes.

Therefore, the present invention embodies characteristics other than the positive characteristics of the spring over the entire operating range of the spring, and also makes it possible to adjust the characteristics, so that the characteristics can be effectively utilized in a wide range of fields. The purpose is to provide a new spring device.

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a spring, a limiting member that limits the operating range of the spring, and a moving member that moves between the eye control members. At least one of the limiting member and the moving member is composed of an electromagnet. Here, the characteristics other than the positive characteristics of the spring are:
The negative characteristic is that the load decreases as the deflection increases, and the constant load characteristic is that the load remains constant even if the deflection increases.

[Operation] According to the above configuration, a magnetic attraction force acts between the limiting member and the moving member, and this magnetic attraction force and the load for the deflection of the spring are combined, so that the entire device has positive characteristics. Operates with characteristics other than

In this case, the magnetic attraction force can be changed as appropriate by adjusting the magnetic force of the electromagnet.

[Example] Hereinafter, the present invention will be specifically described with reference to the accompanying drawings.

In addition, in the description of the drawings, the same elements are given the same reference numerals and redundant description will be omitted.

FIG. 1 is an explanatory diagram showing a first embodiment of the present invention, which includes a compression spring L, a limiting member 2, a moving member 3,
A spring device is constituted by a detection means 4 that detects movement of the moving member 3 and a control means 20 that adjusts the magnetic attraction force. The spring 1 is wound at an equal pitch, and the limiting member 2
is installed on. The limiting member 2 is attached to the fixed side base 5, and the spring receiver is the seat 6, and the spring receiver is the seat 6.
The shaft 7 is integrally formed so as to extend upward from a substantially central portion of the shaft 7, and a stopper plate 8 is screwed onto the upper end of the shaft 7. The spring 1 is fitted onto the shaft 7 of the limiting member 2, and the lower end of the spring receiver is supported by the seat 6, and the upward movement of the moving member 3, which will be described later, is limited by a stopper plate 8. The operating range of the spring 1 is limited by the seat 6 and the stopper plate 8. The moving member 3 has a head part 9 and a leg part 10, and the upper end part of the head part 9 is connected to a pressurizing body 13.
The stopper plate 8 of the limiting member 2 is inserted into the lower end portion to form a hollow rectangular box shape. The leg portion 1o of the moving member 3 has a double structure consisting of an inner tube and an outer tube, and is connected vertically from the lower end of the head 9. A cylindrical electromagnet 11 is attached between the inner tube and the outer tube of the leg portion 10. The shaft 7 of the limiting member 2 is loosely inserted into the inner tube of the leg 1o, while
The outer tube of the leg 10 is inserted into the spring 1. In addition, the head 9 has a larger diameter than the leg 10, and a step 12 is formed at the boundary between these parts, expanding outward, and the upper end of the spring 1 comes into contact with this step 12. There is. This not only limits the operating range of the spring 1 described above, but also connects the upper end surface of the movable member 3 to the pressure body 13 and
When a load is applied by 3, the movable member 3 moves along the shaft 7 against the biasing force of the spring 1. In contrast to the moving member 3 having such an electromagnet 11, the entire limiting member 2 or at least the stopper plate 8 and the spring receiver seat 6 are formed of a magnetic material. Therefore, when the electromagnet 11 is activated, the moving member 3 and the limiting member 2
A magnetic attraction force acts between them. The detection means 4 is provided along the shaft 7 of the restriction member 2.

The detection means 4 includes a light sensor or an image sensor consisting of a light emitting element and a light receiving element, or a Hall element, and is arranged at predetermined intervals along the length of the shaft 7. This detection means 4 detects movement information such as the movement position and movement speed of the moving member 3, and in the case of an optical sensor, one of a light emitting element and a light receiving element is provided along the shaft 7, and the other is provided. is provided on the moving member 3. Each sensor provided along the length of the shaft 7 is connected to a signal line 15, which in turn is connected to a control means 20. The control means 20 includes a movement detection section 21 and a control section 2.
2. A magnetic force adjustment section 23 is provided, and a movement detection section 21 is connected to the signal line 15. Movement information of the moving member detected by the detection means 4, such as movement position and movement speed, is input to the movement detection section 21, and this movement information is sent to the control section 22. The control unit 22 stores programs such as a comparison circuit and an arithmetic circuit for adjusting the magnetic force of the electromagnetic force 11, and also stores desired target values. The control unit 22 calculates the optimum magnetic force from the movement information input from the movement detection unit 21.

The magnetic force adjustment section 23 is controlled by this control section 22,
The current supplied to the electromagnet 11 is adjusted. Therefore, the magnetic force of the electromagnet 11 is adjusted by the magnetic force adjustment section 23, and the magnetic attraction force of the stopper plate 8 and the spring receiver to the seat 6 is adjusted.

Next, the operation of this embodiment will be explained.

Generally, the magnetic attraction force of the electromagnet 11 that acts on the stopper plate 8 and the spring holder 6 made of magnetic material is inversely proportional to the distance between these magnetic materials 8, 6 and the electromagnet 11, and is proportional to the magnetic force of the electromagnet 11. . Further, the amount of deflection of the compression spring 1 increases or decreases in proportion to the load from the pressurizing body 13, and as the amount of deflection increases, the biasing force (that is, restoring force) opposing the load increases. FIG. 2 shows these characteristic diagrams, and the characteristic curve A is the deflection-load curve of the compression spring 1, and its slope is the spring constant (positive). Characteristic curve B is a curve of the magnetic attraction force of the electromagnet 11 acting on the stopper plate 8, and characteristic curve C is a curve of the magnetic attraction force of the electromagnet 11 acting on the spring bearing seat 6. Since this electromagnet 11 is inserted into the compression spring 1 and is provided within its action range, the compression spring 1
When the spring holder is bent, the distance between the stopper plate 8 and the electromagnet 11 increases by the same amount, and the distance between the seat 6 and the electromagnet 11 of the spring receiver decreases. Therefore, the amount of deflection of the spring, which is the horizontal axis, is the distance between the stopper plate 8, which is a magnetic material, and the spring receiver, and the seat 6 and the electromagnet 11. In this embodiment, since the magnetic body 6.8 is provided in the length direction of the coil of the compression spring 1, the load for the deflection of the compression spring and the magnetic attraction force of the electromagnet 11 are in the same direction, and these loads and the magnetic attraction force are in the same direction. The characteristic curve obtained by combining the suction force and the suction force is the deflection-load curve of the spring device of this embodiment. Further analyze the characteristic curve. In this case, the magnetic force of the electromagnet 11 is adjusted to a constant value. In the initial state where no pressurizing force is applied by the pressurizing body 13, the amount of deflection of the compression spring 1 is "0".
In this state, the electromagnet 11 is at the uppermost position, and the distance between the spring receiver and the seat 6 is the maximum, so the magnetic attraction force between them is also "0". Therefore, in the initial state, only the magnetic attraction force between the electromagnet 11 and the stopper plate 8 acts effectively on the entire device. Next, the pressurizing body 13
When pressurized, a downward external force acts on the moving member 3, which causes the compression spring 1 to bend, increasing the spring load along the characteristic curve A, and increasing the distance between the electromagnet 11 and the stopper plate 8. The magnetic attraction force between them is characteristic curve B.
decreases along. On the other hand, since the movable member 3 approaches the spring receiver and the seat 6, and the distance between the electromagnet 11 and the spring receiver and the seat 6 decreases, the magnetic attractive force between them increases along the characteristic curve C. Since the magnetic attraction force acting on this distance is in the same direction as the pressing direction, the pressing force applied to the device is reduced. Therefore, the characteristic curve of the entire device decreases and exhibits a so-called negative characteristic.If the pressurization is continued, the amount of deflection of the spring 1 increases, and the spring load of the spring 1 resisting the pressurizing force becomes linear. However, at the same time, the electromagnet 11
As the magnetic attraction force between them approaches , it increases steeply exceeding the spring load, resulting in a significant negative characteristic of the entire device. Therefore, even if the amount of deflection of the spring 1 increases, the device as a whole exhibits negative characteristics, so it can be operated with a small pressing force.

In this embodiment, the movement of the movable member 3 is detected by the detection means 4, and the control means 20 adjusts the magnetic force of the electromagnet 11 based on information from the detection means 4. For example, when the magnetic force of the electromagnet 11 is adjusted to be large, the magnetic attraction force between the electromagnet 11 and the stopper plate 8 due to the movement of the moving member 3 becomes characteristic curve B,
Therefore, the magnetic attraction force between the electromagnet 11 and the barb holder 6 is the characteristic curve C+. The characteristics of the entire device consisting of the magnetic attraction force and the spring load of the barbs 1 exhibit a negative characteristic with a steep downward curve as shown in the characteristic curve.On the other hand, the magnetic force of the electromagnet 11 is small. When adjusted so that the magnetic attraction force between the electromagnet 11 and the stopper plate 8 becomes a characteristic curve B2, the magnetic attraction force between the electromagnet 11 and the spring bearing plate 6 becomes a characteristic curve C2, and the characteristics of the entire device are is a characteristic curve. With this characteristic, a flat portion d2 which is a constant load region is obtained, and when moving the moving member 3, it is possible to move it with a constant load. Therefore, by providing the detection means 4 and the control means 20,
Since the characteristics of the device can be adjusted arbitrarily, the range of application can be widened.

In this embodiment, an electromagnet divided into upper and lower halves may be used as the electromagnet 11, and each electromagnet may be controlled by a control means. In this case, finer adjustment can be performed.

FIG. 3 shows a second embodiment of the invention. In this embodiment, the stopper plate 8 and the spring receiver seat 6 of the limiting member 2 consist of a cover block 16 and an electromagnet 17 mounted within the cover block 16, and each electromagnet 17 is connected to the control means 2o. - On the other hand, a ring body 18 made of a magnetic material is fitted into the leg portion 10 of the moving member 3, and a magnetic attraction force acts between the stopper plate 8 and the spring receiver of the limiting member 2 and the seat 6. It has become. Therefore, in this embodiment as well, by adjusting the magnetic force of the electromagnet 17, it is possible to obtain negative characteristics or characteristics other than positive characteristics such as constant load property, but since the electromagnet 17 is provided at a fixed position, the control means There is an advantage that the connection structure with 20 is simplified.

The present invention is not limited to the above embodiments, and various modifications can be made. For example, electromagnets may be provided on both the limiting member and the moving member. Further, an electromagnet and a permanent magnet may be combined and used as a limiting member or a moving member.

[Effects of the Invention] As described above, the present invention combines the spring load with respect to deflection and the magnetic attraction force acting between the moving member and the limiting member, so that the device as a whole has characteristics other than positive characteristics. Since it embodies this, it is possible to obtain negative characteristics or constant load characteristics over the entire movement range of the moving member.

Moreover, since an electromagnet is used as the magnetic attraction force generating member, the pattern of its characteristic curve can be changed as appropriate, and the spring device can be made to exhibit characteristics other than positive characteristics, which has a wide range of applications. It will be widespread.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a first embodiment of the present invention, FIG. 2 is a deflection-load characteristic diagram thereof, and FIG. 3 is a sectional view of a second embodiment. 1... Spring (compression spring), 2... Limiting member, 3...
- Moving member, 4... Detection means, 11.17... Electromagnet, 20... Control means. Patent applicant: NHK Spring Co., Ltd. Agent: Hideaki Sato, patent attorney

Claims (1)

[Claims] 1. A spring, a limiting member that limits the operating range of the spring, and a moving member that moves between the limiting members, wherein at least one of the limiting member or the moving member is A spring device characterized by consisting of an electromagnet. 2. The spring device according to claim 1, comprising: a detection means for detecting movement of the moving member; and a control means for adjusting the magnetic force of the electromagnet based on information from the detection means.