JPS58128618A - Collision speed detector - 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 The present invention relates to a collision speed detector mounted on a vehicle or the like, and more particularly to a collision speed detector that has a rotating moving body and detects double integral acceleration.

An example of the structure of a conventional collision speed detector of this type is shown in FIG. A guide means 3 is supported and fixed by an insulating member 2 attached to an end of the casing 1 and the other end of the casing 1.

This guide means 3 has a spiral groove cut therein, and a movable body 4 that can move forward and backward along the spiral groove is inserted into the line guide means. This moving body 4 has a sliding member 5 through which the guide means 3 passes through the center, and 11! between the sliding member 5 and the guide hand R3! It consists of a plurality of balls 6 disposed between the oscillator and a metal inertia member 7 that holds the sliding member 5 from the outside.

Further, this movable body 4 is pressed toward the side opposite to the insulating member 2 by an elastic body 8 mounted around the guide means 3. Furthermore, a pair of contact pieces 9A and 9B are fixedly provided on the insulating member 2, and this contact piece 9A.

A contact point at the tip of 9B comes into contact with a conductive member 10 attached to the side surface of the movable body 4. Also,
The other end of the contact piece 9A is connected to the positive electrode side of the power source 11, and the other end of the contact piece 9B is connected to the load 12. Note that the negative electrode side of the power source 11 and the other end of the load 12 are grounded.

In a collision speed detector having such a conventional multi-thread ball screw structure, the movable body 4 is moved by the contact piece 9 due to the impact of the collision.
A and 9B, the contacts are made conductive to flow current to the load 12, and the acceleration at that time is detected from this ta. However, the movable body 4 can accurately follow shocks with a long period of 12 to 20 rn seconds or more, such as the one shown in A of No. 2@l, but the following shock as shown in B of FIG. In a short-period impact of about 3 to 8 msec, high positive and negative accelerations act, and the contact pressure between the point contact ball 6 and the spiral groove of the guide means 3 increases, resulting in an increase in the coefficient of friction. This has the drawback of deteriorating screw efficiency and deteriorating detection sensitivity.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks and provide an I1II thrust velocity detector whose detection sensitivity does not change depending on the type of impact.

In order to make the entire moving object follow the short period acceleration of 3 to 8 msec, the moving object should be brought into surface contact with the guide means to suppress the contact surface pressure, and the coefficient of static friction and the coefficient of dynamic friction should be adjusted. Focusing on the need to reduce the difference between stick-slip and eliminate the loss time caused by adjusting the distance between the guide means using ball rollers, we developed a self-lubricating property for the moving body. The above object is achieved by providing a fluororesin nut with a structure such that the nut slides along the spiral groove of the guide means.

Hereinafter, embodiments of the present invention will be explained with reference to the drawings, using the same reference numerals for the same parts as those of the conventional example.

FIG. 3 is an explanatory diagram showing the structure of one embodiment of the collision speed detector of the present invention. A guide means 3 is supported and fixed in the casing 1 by the insulating member 2 and the end of the casing 1.
is provided. A movable body 4 is inserted into the guide means 3, and the movable body 4 is pressed by an elastic body 8 mounted on the outer periphery of the guide means 3. Insulating member 2
A pair of contact pieces 9A and 9B are fixedly attached to the movable body 4, and a conductive member 10 is attached to the side surface of the movable body 4, with which the contacts of these contact pieces 9A and 9B come into contact. Furthermore, contact pieces 9A, 9B
The ends of are connected to a power source 11 and a load 12. Up to this point, the configuration is similar to the conventional example.

As particularly shown in FIGS. 4 and 5, in the movable body 4 of this embodiment, the sliding member 13 that comes into sliding contact with the guide means 3 has a fifth
The guide means 3 shown in the figure has a convex portion having a shape that fits into the inner cavity 14, and this convex portion slides along the spiral groove of the guide means 3 to guide the movable body 4. Rotate and move. The moving body 4 is constructed by integrally combining the sliding member 13, the inertial member 7, and the conductive member 10. Note that a liquid lubricant 15 is interposed between the helical convex portion of the sliding member 13 and the helical groove of the guide means 3. Furthermore, the elastic body 8
Both ends of are respectively locked to the insulating member 2 and the inertial member 7 of the movable body 4, and normally the contact pieces 9A and 9B are electrically separated, and the power source 11 and the load 12F! , there is no continuity.

Now, when a vehicle collides, if the direction of the arrow G shown in FIG. 3 is positive, the moving body 4 receives the impact energy due to the acceleration α(1) shown in FIG. At the same time, the energy is converted to the elastic body 8, and when a predetermined amount of energy is converted, the contact pieces 9A and 9B are short-circuited to supply power from the power source 11 to the load 12 connected to the outside.

Therefore, the sliding member 13 of the moving body 4 is molded from a composite resin containing a fluorinated resin with excellent self-lubricating properties, and the spiral convex portion formed on the sliding member 13 allows It is in surface contact with the spiral groove of the guide means 3. Therefore, l1If' does not deform under various usage conditions.
# In order to ensure the appropriate contact pressure to demonstrate the characteristics,
The shape and dimensions of the sliding member 13 have been determined. In actual collisions, the period and acceleration differ depending on the object, as shown in the A waveform and B waveform in Figure 2. Therefore, the dimensions and shape should be designed so that the contact surface pressure is optimal under the conditions where the maximum acceleration occurs, and the mechanical strength is determined. is ensured.

On the other hand, under operating conditions where only small accelerations occur, the contact surface pressure of the sliding member 13 is small, and in order to compensate for the decrease in self-lubricating effect, a liquid lubricant (for example, silicone oil)
5, the movable body 4 can rotate smoothly along the guide means 3 under all conditions of use. (9) The inertia member 7 constituting the movable body 4 is made of a metal material, and functions as a means for reinforcing the sliding member 13, a means for connecting the conductive member 10, and a means for increasing the rotational moment of inertia.

In the movable body 4 of this embodiment, no ball is interposed between the guide means and the sliding member as in the conventional case.
There is no loss time such as the moving body 4 starting to move until the load is evenly applied to the plurality of balls, and stable detection sensitivity can be obtained even under high frequency dump sine acceleration as shown in B in FIG.

FIG. 6 shows the acceleration α (electricity) of the counter-pressure sinusoidal wave of half-wave vibration, and the velocity v0 corresponding to the area of this half-sine wave is expressed by the following equation.

v0=fTh(t)dt・・・・・・・・・(1) 7th
The figure shows the acceleration α(1) of a high-frequency Danops sine wave, and the velocity Ft v corresponding to the area of this wave.

is expressed by the following equation. However, in the figure, it is T, +'r.

"4T・v0=a (t) d t・""・
(2) The table below compares the accelerations shown in FIGS. 6 and 7 between the conventional detector and the detector of this embodiment.

As can be seen from the table, in the conventional detector, v.

When the ratio of /V· is 1 or more, the deterioration in sensitivity to the high frequency dumped sine wave is clearly reduced. However, in the detector of this embodiment, the ratio vm''/ve is approximately 1, and it can be said that no deterioration in sensitivity to high-frequency damped sine waves occurs.

According to this embodiment, the helical convex portion formed on the sliding member 13 of the movable body 4 directly engages with the helical groove of the guide means 3, thereby achieving surface contact that can suppress the contact surface pressure. By reducing the difference between the coefficient of static friction and the coefficient of dynamic friction, and eliminating the loss time due to alignment with the ball, stable detection sensitivity can be obtained even under high-frequency dump sine acceleration of the wing period. The effect of always maintaining a constant detector If regardless of its length can be seen. nine,
#Ninth sliding member 13 that does not use a ball or the like for the moving body 4
Since it can be molded using synthetic resin, it has the effect of reducing costs.

Furthermore, since there is no high-density member such as a ball on the inner periphery of the movable body 4 as in the conventional case, and the inertia member 7 with high density is arranged on the outer periphery of the movable body 4, rotational movement of the movable body 4 is prevented. Since the inertial mass inside can be increased and the acceleration integral calculation distance can be shortened, the detector can be made smaller. Further, since the liquid lubricant 15 is used to compensate for the lack of self-lubrication under low acceleration, stable detection sensitivity can always be obtained.

FIGS. 8 and 9 are diagrams showing other embodiments of the present invention. In this embodiment, since the detector is attached to a part of the bumper of the kite and is not able to withstand vibrations while the kite is running, the 11i! In order to supply y- without continuing the agent, an annular oil reservoir recess 16 is formed on the sliding surface of the sliding member 13. An oil-impregnated member 17 containing a liquid lubricant 15, such as felt or porous resin, is filled in the concave portion 16 of this circular oil reservoir to prevent oil from running out. The other configurations are the same as those in the previous example, so illustration and description will be omitted.

The present embodiment has the same effects as the Tizen Kyo embodiment, but is especially effective in not running out of oil and achieving stable detection sensitivity even at low accelerations.

As described above, according to the collision velocity detector of the present invention, it is possible to provide a collision velocity detector whose detection sensitivity does not change depending on the type of impact.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing the structure of a conventional collision speed detector.
Figure s42 is a diagram showing an example of acceleration during a collision that acts on the collision speed detector, Figure 3 is an explanatory diagram showing the structure of an embodiment of the collision velocity detector of the present invention, and Figure 4 is a diagram showing the structure of an embodiment of the collision velocity detector of the present invention. FIG. 5 is an enlarged cross-sectional view of the moving body 4 shown, and FIG. 5 is a v-v cross-sectional view of FIG.
The figure is a diagram showing the acceleration number form of oscillation, and Fig. 7 shows the acceleration waveform of the frequency dump psi/wave f! :, line diagram, FIG. 8 is a wT side view of a moving body which is a main part of another embodiment of the present invention,
FIG. 9 is a sectional view taken along the line -■ in FIG. 8. 1...Casing, 3...Guiding means, 4...Moving body, 4-senyu S-related

Claims (1)

[Claims] 1. A casing, a movable body movable with respect to the casing, a spiral guide means capable of rotating the movable body to move it forward and backward, and absorbing the kinetic energy of the movable body. In a collision speed detector comprising an elastic body and a switch that closes when the linear moving body moves a predetermined distance against the elastic body, the moving body is configured to move along the guide means. A collision characterized by comprising a sliding member made of a material containing a low-friction resin such as a resin, and an inertia member made of a material having a density greater than that of the sliding member fixed to the outer periphery of the sliding member. speed detector. 2. Claim 1, characterized in that a spiral groove is provided on the outer circumferential surface of the guide means, and a spiral convex portion that slides by engaging with the spiral groove is formed on the sliding member. Collision velocity detector as described in section. 1. The moving body is characterized in that it engages with the guide means via a liquid lubricant. Collision velocity detector according to item 1. 4. The collision speed detector according to claim 1, wherein a recess for an oil sump is formed in the sliding surface of the sliding member, separate from the groove corresponding to the guide means. & The collision speed detector according to claim 1, wherein a circular concave portion is provided on the sliding surface of the sliding member, and an oil-impregnated member containing lubricating oil is inserted into the concave portion.