JP2767263B2 - Shock absorbing mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Objects and Fields of the Invention) The present invention relates to a mechanism for absorbing a shock applied to an object by a magnet.

In general, as a cushion mechanism for absorbing an impact, a mechanism using an elastic spring and a mechanism using a compressor are well known.

However, in the shock absorbing mechanism using the elastic spring, when the fluctuation distance of the spring is x, the restoring force is proportional to x, so the external force is f (t), and the mass of the object receiving the shock is m. In this case, the equation of m + λ = f (t) −kx is established.

(However, is the amount that differentiates x once, that is, the speed, and x is 2
K is the elastic constant of the elastic spring, λ
Is the damping constant of the elastic spring. As is apparent from solving the ordinary linear differential equation, the term kx exists in the above equation, so that the ordinary case (k ² <
In the case of 4mλ), there is an excessive solution oscillating by a sine wave.

This means that even if the impact is absorbed by the elastic spring, the tip of the spring and the object connected to the spring vibrate with a sine wave.

On the other hand, when the air compressor is used, and the variation distance from the reference position of the air compressor is x due to impact, the equation of m + λ = f (t) −k / (x + x ₀ ) is established by Boyle's law. I do.

(However, is the amount that differentiates x once, that is, the speed, and x is 2
Times obtained by differentiating the Ryomotochi acceleration, K is a proportional constant, x ₀ is the length of the cylinder when no external force is applied in the air compressor, lambda is the attenuation constant) above formula nonlinear (non-linear) Although there is a solution represented by a complicated special function, a vibration term that normally oscillates with time occurs in this case as well.

In other words, in a conventional shock absorbing mechanism using an elastic spring or an air compressor, even if the shock is once absorbed, a vibration term is generated later, so as a shock absorbing mechanism for preserving a substance having a high degree of rest. It was not enough to use.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a shock absorbing mechanism that controls an attractive force or a repulsive force between opposing magnets to relax an external shock without a vibration term.

(Constitution of the Invention) The constitution of the present invention is as follows: (1) At least one of two opposing magnets is an electromagnet, the distance between the centers of the opposing magnets is x, and the current conducted to the electromagnet is I, Means for storing, for each x, a value F (x) which is a value obtained by an experiment in advance and which is obtained by dividing the force acting between the opposed magnets by I, corresponding to each x; Means for measuring x at the time of operation, and a device for outputting the stored value corresponding to x based on the measured value, and outputting (where x represents an amount obtained by differentiating x with respect to time).・ A shock absorbing mechanism is provided by installing a control mechanism so as to make the amount proportional to 1 / F (x), whereby the externally applied shock is mitigated by the force acting between the magnets. (2) Opposition Is provided, and the distance between the centers of the electromagnets is x, Husband current conducted to the opposing electromagnets s I _1,
As I _2, corresponding to each x, a value obtained by experiment in advance, said force mutually acting between the opposed electromagnets
Means for storing the value F (x) divided by I ₁ and I ₂ corresponding to each x, means for measuring x at the time of operation, and outputting the stored value corresponding to x based on the measured value. with, a device for outputting (represents the amount obtained by differentiating in time x), the I ₁ · I ₂ (|| represents an absolute value). If x is to be increased by an externally applied impact (> 0), the opposing electromagnets attract each other and are applied externally. When x decreases due to impact (<
0), I ₁ and I ₂ so that the opposing electromagnets repel each other.
And a shock absorbing mechanism by which a shock applied from the outside is reduced by a force acting between the opposing electromagnets.

First, the configuration described in the above (1) will be described.

In the invention described in the above (1), as shown in FIG. 1, at least one of the opposing magnets 1 is an electromagnet 11,
11 is provided with a control mechanism 2 for a current flowing through the switch 11.

Hereinafter, specific examples of the facing magnet and the electromagnet will be described.

As shown in FIG. 2 (a), an electromagnet was wound around a magnetic body having a magnetic moment τ by helically winding N times in the same direction as the polarity of the magnetic body and having a length of 2 l. In the case, the magnitude of the magnetic field in the polarity direction of the magnetic body at the center position of the magnetic body is Becomes

(Where x is the distance between the center of the magnetic body and the center of the coil, x> l, and l >> a). Therefore, the force acting between the coil and the magnetic body is −d ( H · τ) / dx (d represents a differential symbol) = (NIa ² /
2) {1 / (xl) ³ -1 / (x + 1) ³ }.

In the case of the 2 (a) view if Saleh is, F (x) = (Na 2/2) {1 / (x-l) 3 -1 / (x + l)
³ ｝.

Therefore, I is-· 1 / F with respect to F (x) as described above.
It will conduct an amount proportional to (x).

As shown in FIG. 2 (b), the strength of the magnetic pole is m at a distance of x from the center on the central axis of the electromagnet with respect to the electromagnet caused by passing the current I through the circular circuit wound N times with the radius A. When a thin magnetic rod with a magnetic axis length of 2l (x >> l) is made to coincide with the circle and the axis of the circular circuit, the force acting between the circuit and the magnet is obtained as follows. .

The magnetic flux density component in the radial direction from the center of the circle of the circular coil
When B _1, by Fleming's left hand rule, 2PaiaB
₁ I force acts.

Accordingly, when the portions generated from the + m pole and the −m pole in FIG. 2B are B ₁ ⁺ and B ₁ ⁻ , B ₁ ⁺ = (ma / 4π) · ｛(xl) ^{2 _{+ a 2} -3/2 B 1 -}} = - (ma / 4π) · {(x + l) 2 + a 2} because it is ^-3/2, the force acting between the circular coil and the magnetic body, 2πNI (B ₁ ^{+ +} B ₁ ^-) = a (mNa ² I / ^{2) [{(x-l) 2 +} a} -3/2 {(x + l) 2 + a 2} -3/2 ].

If Saleh, the ^{F (x) = (mna 2} /2) {(x + l) 2 + a 2} -3/2 {(x + l) 2 + a 2} -3/2 ].

Therefore, the current I conducted to the circular circuit is an amount proportional to the reciprocal 1 / F (x) of F (x) according to the above equation.

In the specific example of the above (1), any of a magnetic body and an electromagnet can be adopted as the magnet facing the electromagnet.

In the configuration described in the above (1), when a current I = −k ·· F (x) conducted to the electromagnet (k is a positive proportional constant), a force I · F (x) =-k.

Therefore, when the distance between the two magnets is to be increased (> 0) due to an external impact force, I · F (x) = − k <0, which means that the attractive force between the opposing magnets is small. Means to act.

On the other hand, in the case where the distance between the opposing magnets is to be reduced by an external impact (<0), IF (x) = − k> 0.

That is, in this case, it means that a repulsive force acts between the two magnets.

Then, the current I conducted to the electromagnet is made not proportional to .multidot.I / F (x) but to -.multidot.1 / F (x) because the distance between the two magnets due to external impact force If the two magnets are to be separated from each other, a mutual attraction force is applied.If the two magnets approach each other due to an external impact force, the two magnets are repelled against each other. There is no other way to apply force.

Next, the configuration described in the above (2) will be described.

In the configuration described in (2) above, as shown in the schematic diagram of FIG. 3, both opposing magnets are electromagnets 11, and a control mechanism 2 for controlling currents I ₁ and I ₂ conducted to the electromagnets 11 is provided. become.

 Hereinafter, a typical case will be described.

As shown in FIG. 4 (a), in the case where circular coils having a radius of a, the number of windings being N, and conducting currents of I ₁ and I ₂ , respectively, are opposed to each other with their central axes coincident. And when the distance x between both coils is sufficiently larger than the radius a (x >>
Consider the case a).

In general, for a circular coil wound N times with a radius a, a magnetic field H _r and θ in the r direction at a distance r from the center and an angle θ.
The magnetic field H _{θ in the} direction is H _r = (INa ² · cos θ) / 2r ³ H _θ = (INa ² · sin θ) / 4r ³ .

In FIG. 4 (a) And It is.

On the side of the electromagnet 2, of the magnetic field by the coil 1, the component of the magnetic field generated in the actinomycetes direction of the coil 2 in the case of the H ₁ is Becomes

in this case, Since it is, the force acting between the coils becomes _{2πaI 2 NμH 1 = 3πI 1 I} 2 μa 3 sinθ · cosθ / 2r 3 = 3πI 1 I 2 Nμa 4 x (x 2 + a 2) -5/2 (However, μ: magnetic constant).

Then, F (x) = 3πμa ⁴ N ² x (x ² + a ² ) ^−5/2 .

Therefore, the currents I ₁ and I ₂ conducted in the two circular coils are proportional to the square root of the absolute value of the product of F (x) reciprocal 1 / F (x) according to the above equation.

As shown in FIG. 4 (b), a constant current is applied to an infinitely long copper wire.
Circular current with I ₁ and I ₂ conducting, radius a and number of windings N
When I ₁ and I ₂ are conducted in the same plane and the length of the distance from the center of the circular coil to the DC current is x, the force acting between the two coils is obtained as follows.

Magnetic field generated from the current I ₁ at the position of P of the circular coil in the first 4 (a) diagram, with respect to a direction perpendicular to the plane of the circle, and _{H = I 1 / {2π (} x-a cosθ)}.

Therefore, when the angle of the point P is aθ, the force acting on the point P is dF = μ ₀ HI ₂ ds = μ ₀ I ₁ I ₂ ad θ / ｛2π (x −a cosθ)｝.

Because ingredients parallel with the inner linear current I ₁ of the aF is throughout the circular current I ₂ mutually cancel one another, component perpendicular to I ₁ is the force acting on each other.

Therefore, the combined power is Becomes

Therefore, the linear current I ₁ and the circular current I ₂ are controlled so as to be proportional to the parallel root of the absolute value of the product of F (x) and the reciprocal 1 / F (x) of the above equation.

As described above, FIGS. 2 (a), 2 (b) and 4
In the shapes shown in FIGS. 4A and 4B, the force acting between the magnet and the coil and the F (x) corresponding thereto can be obtained by relatively simple calculation.
Actually, it is often not easy to calculate. In addition, in each of the above-described drawings, it is assumed that an iron core is not inserted as an electromagnet, but since the iron core is actually inserted in the coil, the magnitude of the magnetic force lines is also large in each of the above-described drawings. And the shape is different, so that F
It becomes a complicated form compared with (x).

In such a case, it is essential that the actual F (x) is obtained in advance by experimentally obtaining F (x) corresponding to each x and stored in the storage device.

In the present invention, it is indispensable to output an output proportional to 1 / F (x) and to input a current corresponding to the output.

That is, in order to determine the temporal change of the distance between the two magnets, a speedometer is installed on one of the moving magnets or an object that is integral with the magnet, or the distance x between the two magnets is measured, and the differential amount is determined. Can be achieved by:

In any case, the value of 1 / F (x) is practically indispensable to use a microprocessor or a computer (Either a digital computer or an analog computer can be used, but an analog computer has Since the value of 1 / F (x) can be sequentially calculated according to the continuous change of the value of x, it will be convenient.)

Similarly, in the configuration described in the above (2), the currents I ₁ and I ₂ conducted to both electromagnets are In other words, the time change of the distance between the two magnets is always caught and found, It is necessary to ask for.

However, in the configuration described in the above (2), the magnitudes of the two currents are controlled as described above. However, certain conditions are naturally required for the directions for the purpose of the present invention.

That is, when the distance between the two electromagnets is to be increased by an external impact (> 0), the directions of I ₁ and I ₂ are set so that the two electromagnets have an attractive force, and the external When the distance between the two magnets is about to decrease due to impact (
In <0), the current is set so that a repulsive force is generated between the two electromagnets.
It is necessary to set the directions of I ₁ and I ₂ .

Thus, in the present application, − · 1 / F (x) or Is indispensable, and when performing these calculations, for each x that is an input, the value of x when the value is output may already be slightly different due to a time delay (time lag). This can be addressed by increasing the computational speed of the computer to minimize errors.

(Effects of the Invention) In the configuration according to the above (1), when one of the opposed magnets and the entire mass of the object integrally formed with the magnet are M and an impact force f (t) is applied thereto. The equation of motion is: M = f (t) + IF (x).

Here, I is a current that is conducted by one of the electromagnets and is controlled in accordance with a change in the distance x between the electromagnetic waves.

Here, since I = −k · 1 / F (x), M + k = f (t) in the above equation.

Similarly, in the configuration described in (2), one of the opposing electromagnets and the entire mass M
And then, contrast equation of motion when an impact force f (t) has been added becomes M = f (t) · I 1 · I 2 F (x).

As described above, in the direction of the currents I ₁ and I ₂ , when the distance between the two electromagnets is to be increased (> 0), the attractive force acts to reduce the distance between the two electromagnets (<0).
0), a repulsive force acts, so I ₁ · I ₂ · 1 /
F (x) is -k as in the case of the configuration described in the above (1).
(In the case of + k, the object of the present invention cannot be achieved.) Then, even in the configuration of the above (2), M + k =
f (t) holds.

Since the configurations described in the above (1) and (2) have the same equation, the operation and effect of the present invention will be unified and discussed below.

Here, when an impact by a δ function is considered as the impact f (t) as shown in FIG. 5 (a), M + k = Aδ (t).

(Where A is an amount representing the magnitude of the impact force) In this case, the solution of the differential equation is x = x ₀ −Ae− ^{kt / M} / k, which is as shown in FIG. 5 (b). It becomes a curve.

(However, x ₀ is the initial value when t = 0) Also, when an impact force having a size times the width a of A as shown in FIG. 5 is applied is, M + k = A {I (t ) −I (t−a)}.

(However, I (t) is a step function, and I (t) = 0 (t <0) = 1 (t ≧ 0).) In this case, the solution of the differential equation is x = x ₀ + ^{{t- (1-e -kt /} M)} A / k (0 <t <a) = x 0 + {a + (1-e -ka / M) e -kt / M · M / k} A / k (t ≧ a), which is a curve as shown in FIG. 6 (b).

(However, x ₀ is an initial value in the case of t = 0.) Thus, even when a δ function type impact force or a rectangular wave type impact force is applied, as seen in the solution of the differential equation,
The variation of the position between the two magnets is due to an exponential decay curve, and is only a gradual variation.

This is because the current applied to the electromagnet was controlled as described above, thereby causing an attenuation term due to k in the differential equation.

Thus, in the present invention, even if one or both of the facing magnets or their connected objects are subjected to an impact force, the gap x between the two magnets is applied to one or both of the facing magnets at that moment. The current corresponding to the fluctuation of
As a result, a repulsive force against the impact is generated, so that the variation of the magnet and the object connected thereto gradually changes exponentially, and the impact is absorbed.

Also, the current conducted to the electromagnet and .1 / F (x) (in the case of the above-mentioned (1)) By changing the proportionality constant k with respect to (in the case of the configuration (2)), it is possible to arbitrarily set the degree of attenuation associated with the instantaneous fluctuation of the impact. It is also possible to select the degree.

Needless to say, since there is no vibration due to a sine wave as in the case of an elastic burr or a compressor, an extremely large and stable state can be maintained against a so-called impact.

In addition, the current to be ignited is proportional to the amount of time obtained by differentiating the distance between the two magnets. Therefore, when x does not change, that is, when no impact force is applied, there is no need to conduct any current, which means It is economical because there is no need to consume unnecessary power.

In the above, the state in which the magnets are opposed in the lateral direction has been described. However, when the magnets are opposed in the vertical direction, it is necessary to support the gravity of the upper object by the magnets.

However, for this purpose, there remains a problem in that a certain distance must be maintained between the two magnets by always conducting a current to one or both electromagnets to repel opposing magnets.

However, this point is also used in combination with the conventional shock absorbing mechanism using an elastic spring or a compressor, and when there is no shock or when the shock is small, the conventional mechanism supports the upper and lower objects and absorbs the shock, and the constant. When a large shock is applied, the structure of the present invention can also be used in a case where the shock absorbing mechanism of the present invention is activated so as to be opposed in the vertical direction.

As described above, the present invention has a wide range of applications in absorbing shock and has epoch-making significance.

[Brief description of the drawings]

FIG. 1: Side view showing the principle of the configuration (1) FIG. 2 (a), FIG. 2 (b): Model diagram showing an embodiment of the shape of the opposed magnet and electromagnet FIG. 3: FIG. 4 (a), FIG. 4 (b): Model diagram showing shapes of opposed electromagnets FIG. 5 (a): Graph showing δ function type shock wave FIG. FIG. 6 (b): a graph showing the response of the change in the distance between the magnets to the shock wave of FIG. 5 (a) FIG. 6 (a): a graph showing a rectangular wave type shock wave FIG. 6 (b): FIG. a) Graph showing the response of the fluctuation of the distance between the magnets to the shock wave shown in the figure: 1 ... magnet, 11 ... electromagnet, 2 ... control mechanism

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-56-70142 (JP, A) JP-A 63-8448 (JP, U) JP-A 53-1588 (JP, U)

Claims (4)

(57) [Claims] At least one of two opposing magnets is an electromagnet, the distance between the centers of the opposing magnets is x,
The current conducted through the electromagnet is defined as I, and a value F (x), which is a value obtained by an experiment in advance and corresponding to each x, obtained by dividing the force acting between the opposing magnets by the I, is defined as I x
Means for measuring the value of x during operation, outputting the stored value corresponding to x based on the measured value, and outputting (where x represents an amount obtained by differentiating x with time). And the above-mentioned I is-· 1 / F (x)
A shock absorbing mechanism by installing a control mechanism that makes the amount proportional to the above, and thereby mitigating an externally applied shock by a force acting between the magnets. 2. The shock absorbing mechanism according to claim 1, wherein each of the magnets provided on the two objects is an electromagnet, and a constant current is conducted to the other electromagnet. 3. The shock absorbing mechanism according to claim 1, wherein, of the magnets provided on the two objects, the magnet of the other object is made of a magnetic material. 4. An opposing electromagnet is provided, a distance between the centers of the electromagnets is x, and currents conducted to the opposing electromagnets are I ₁ and I ₂ , respectively, and are obtained by experiments in advance for each x. Means for storing a value F (x) obtained by dividing a force acting between the opposed electromagnets by I ₁ and I ₂ corresponding to each x, and a means for measuring x during operation When outputs the value obtained by the storage corresponding to x on the basis of the measured values, a device for outputting (represents the amount obtained by differentiating in time x), the I ₁ · I ₂ (|| represents an absolute value). If x is to be increased by an externally applied impact (> 0), the opposing electromagnets attract each other and are applied externally. When x decreases due to impact (<
0), I ₁ and I ₂ so that the opposing electromagnets repel each other.
The shock absorbing mechanism is provided by setting a control mechanism for setting the direction of the electromagnet, thereby reducing the shock applied from the outside by the force acting between the opposing electromagnets.