JPH09138180A - Cylinder for impact test - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform dynamic test and static test using one cylinder for impact test. SOLUTION: The cylinder for impact test comprises a load side cylinder 2, a set side cylinder 1 being applied with a gas pressure lower than that of load side cylinder, a barrier wall 5 having an orifice 4 communicating between the load side cylinder and set side cylinder, and a piston 12 slidable in the set side cylinder. The orifice 4 has area smaller than that of the piston 12 and the piston 12 chokes the orifice to balance the pressing force of gas pressure between the load side cylinder and set side cylinder. A trigger means applies a trigger pressure to the piston thus causing unbalance of pressing force. Consequently, the piston is moved and applied, on the entire surface thereof, with the gas pressure in the load side cylinder so that it can be moved at high speed. A hydraulic cylinder 47 for low speed test, which can push the piston 12 through the orifice 4, is provided in the load side cylinder 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder which can be used for various impact tests of an automobile, for example, and which can be used as both a high-speed test called a dynamic test and a low-speed test called a static test. Related to cylinders.

[0002]

2. Description of the Related Art Various types of test equipment related to automobiles include a high-speed test called a dynamic test and a low-speed test called a static test. The former is a steering impact test, a headrest impact absorption test and the like, and the latter is a headrest load resistance test and the like. In the conventional test apparatus, the high-speed test apparatus and the low-speed test apparatus are separate apparatuses.

Here, an example of a cylinder used in a conventional high-speed test will be described. In FIG. 5, the cylinder is roughly divided into a load side cylinder 2 and a set side cylinder 1. The load-side cylinder 2 and the set-side cylinder 1 are partitioned by an orifice plate 5, and an orifice 4 that connects the load-side cylinder 2 and the set-side cylinder 1 is formed at the center of the orifice plate 5. A piston 12 integrally having a piston rod 8 is slidably provided in the set-side cylinder 1.

An appropriate gas, for example, nitrogen gas is introduced into the set side cylinder 1 from a cylinder (not shown) through a valve and a gas passage, and a constant gas pressure is applied. On the other hand, air and other gases are introduced into the load side cylinder 2. The gas pressure applied to the set-side cylinder 1 is lower than the gas pressure applied to the load-side cylinder 2. The area of the orifice 4 is smaller than the area of the tip of the piston 12, and the piston 12 blocks the orifice 4 so as to balance the pressing force of the gas pressure between the load side cylinder 2 and the set side cylinder 1. Is available. Orifice plate 5
As a trigger means, a trigger gas supply passage 62 for applying a trigger pressure to the tip end surface of the piston 12
Is provided.

[0005] A floating piston 15 is provided in the set side cylinder 1 on the side opposite to the orifice plate 5, and a floating piston 16 is provided in the load side cylinder 2 on the side opposite to the orifice plate 5. These floating pistons 15 and 16 are for adjusting the volumes of the set-side cylinder 1 and the load-side cylinder 2, respectively.
An arbitrary amount of water is sealed between the floating piston 15 and one end of the set-side cylinder 1 and between the floating piston 16 and one end of the load-side cylinder 2, respectively. These floating pistons 15, 1
6 is not essential. On the front side of the piston 12, a pin 9 that penetrates the orifice 4 with a sufficient space is attached. The pin 9 is for adjusting the acceleration of the piston 12, and its outer shape is an arbitrary shape so that desired acceleration characteristics can be obtained. For example, as shown in FIG. 5, if the outer shape of the pin 9 is provided with a large-diameter portion at an intermediate portion in the longitudinal direction, the acceleration is reduced when the large-diameter portion passes through the orifice 4. 5, the acceleration characteristic curve can have two peaks as shown in the lower diagram of FIG.

FIGS. 6 to 8 show the operation of the conventional piston for impact test. However, in FIGS. 6 to 8, the floating pistons 15 and 16 are omitted. The set-side cylinder 1 is supplied with an inert gas at a pressure P1, for example, nitrogen gas, via the valve 30 and the gas supply passage 60. Assuming that the area of the front surface (left side in FIG. 6) of the piston 12 is S3, the rear surface of the piston 12, that is, the area S1 on the side receiving the gas pressure P1 is equal to the area S3.
The area obtained by subtracting the vertical cross-sectional area S of the piston rod 8 from 3, ie, S1 = S3-S. Therefore, the piston 12
Is pressed toward the orifice plate 5 with a pressing force of P1 × S1 = P1 × (S3-S). A flat ridge 12a is provided at the center of the front surface of the piston 12, and the ridge 12a presses against the peripheral edge of the orifice 4 of the orifice plate 5, and as shown in FIG. A flat ring-shaped space 65 surrounded by the piston 12, the orifice plate 5, and the inner wall of the cylinder is formed in a state in which the block 4 is closed. This space 65 is a trigger pressure supply passage 62 having the valve 10.
Is in communication with

With the piston 12 pressed against the orifice plate 5 as described above, the load-side cylinder 2
Is supplied with air at a pressure P2 via the valve 31 and the air supply passage 61. Assuming that the opening area of the orifice 4 is S2, the pressing force applied to the piston 12 through the orifice 4 is P2 × S2. Therefore, this pressing force P2 × S2
And the pressing force P1 × S1 is balanced, and P1 × S1 is actually set slightly larger than P2 × S2, and the state in which the piston 12 is pressed by the orifice plate 5 is maintained. By the way, P2 is set to about 6 times P1, and S1 is set to 6 times or more of S2, for example, about 6.6 to 7.2. However, P1 and P2 may be set to arbitrary values according to the purpose of the experiment.

Next, the valve 10 is opened and air or other gas having a pressure P3 is supplied from the trigger pressure supply passage 62.
When the pressure P3 is applied to the space 65, and the area of the space 65 with respect to the piston 12 is S4, the piston 1
2, the pressing force of P3 × S4 is added. That is, the piston 12, which had been pressed due to the relationship of P1 × S1 vs. P2 × S2 up to then, is P1 × S1 vs. P2.
The pressing force is applied in the relationship of × S2 + P3 × S4, the balance relationship is broken, and the piston 12 is moved rightward in the drawing. When the piston 12 slightly moves to the right in the figure, the pressure P is applied to the entire surface of the piston 12 through the orifice 4.
2 and the piston 12 is moved at high speed.

As described above, since the pressure P2 is set to be several times higher than the pressure P1, a large thrust is generated in the piston 12 and the piston rod 8 at the moment when the trigger pressure P3 is applied. As shown in FIG. 8, the piston 12 and the piston rod 8 move to the right in the figure at a high speed. A dummy doll is attached to the tip of the piston rod 8, and a steering impact test can be performed if the dummy doll collides with a steering wheel of an automobile, and a headrest impact absorption test can be performed if the dummy doll collides with a headrest. Various other so-called dynamic tests can be performed. The object to be moved by the cylinder may be a car body or a part of the car body. As described above, the piston 12
When the piston rod 8 moves at high speed, the gas in the set-side cylinder 1 is compressed and acts as a damper, so that the impact at the end of the piston 12 moving stroke is reduced. When returning the piston 12 to the original position, the valve 32
May be opened to release the gas at the pressure P2. Piston 1
2, a pressing force P1 × S1 is constantly applied to the set-side cylinder 1, and the pressing force
2 automatically returns to the original position shown in FIG.

The gas supplied to the set-side cylinder 1 is inert nitrogen gas because the gas in the set-side cylinder 1 is rapidly compressed when the piston 12 and the piston rod 8 move at high speed as described above. This is because it is necessary to prevent the gas from igniting due to the heat generation.

[0011]

The conventional impact test cylinder described above is dedicated to a so-called dynamic test for moving an object to be moved at high speed, and performs a so-called static test for moving the object at low speed. Can not. Therefore, when performing a static test, another dedicated device must be used.

The present invention has been made in view of the above-mentioned prior art, and has as its object to provide an impact test cylinder capable of performing a so-called dynamic test and static test with one impact test cylinder. And

[0013]

In order to achieve the above object, according to the first aspect of the present invention, a load-side cylinder to which a constant gas pressure is applied and a gas pressure lower than the gas pressure of the load-side cylinder are provided. A set-side cylinder to be hung, an orifice plate formed with an orifice for partitioning the load-side cylinder and the set-side cylinder and communicating the load-side cylinder and the set-side cylinder, and slidably provided in the set-side cylinder. And a piston having an integral piston rod, wherein the area of the orifice is formed to be smaller than the area of the tip of the piston, and the piston closes the orifice by the gas pressure between the load side cylinder and the set side cylinder. The pressing force can be balanced, and the trigger pressure is applied to the tip surface of the piston by the trigger means. The piston is moved by breaking the balance of the pressing force by applying the pressure, the gas pressure of the load side cylinder is applied to the entire surface of the piston, and the piston is moved at high speed, and the movement of the piston gives an impact to the subject. In the impact test cylinder, a low-speed test fluid cylinder capable of pushing the piston through the orifice was provided in the load side cylinder.

According to a second aspect of the present invention, the piston of the low-speed test fluid cylinder and the piston of the low-speed test fluid cylinder can be pressed so that the piston of the low-speed test fluid cylinder can press the piston provided in the set cylinder. And the piston of the same.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an impact test cylinder according to the present invention will be described below with reference to FIGS. However, most of the embodiments of the impact test cylinder according to the present invention are common to the configuration of the above-described conventional example shown in FIG. 5 and the following, and thus common components are denoted by common reference numerals.

In FIG. 1, the cylinders are roughly divided into a load side cylinder 2 and a set side cylinder 1. The load-side cylinder 2 and the set-side cylinder 1 are partitioned by an orifice plate 5, and an orifice 4 that connects the load-side cylinder 2 and the set-side cylinder 1 is formed at the center of the orifice plate 5. An end plate 3 is fixed to an end of the load-side cylinder 2 opposite to the orifice plate 5, and an end plate 7 is fixed to an end of the set-side cylinder 1 opposite to the orifice plate 5. A piston 12 is slidably provided in the set-side cylinder 1. The piston rod 8 is integrally attached to the piston 12 with the intervention of the insert piston 11.

As described above, an inert gas, for example, nitrogen gas is introduced into the set-side cylinder 1 to apply a constant gas pressure. On the other hand, the load side cylinder 2
Is introduced with air or a suitable gas. The gas pressure applied to the set-side cylinder 1 is lower than the gas pressure applied to the load-side cylinder 2. The area of the orifice 4 is equal to the piston 1
The pressure force of the load side cylinder 2 and the set side cylinder 1 due to the gas pressure can be balanced with the piston 12 closing the orifice 4 so as to be smaller than the area of the tip of the cylinder 2. The orifice plate 5 is provided with a trigger gas supply passage 62 for applying a trigger pressure to the distal end surface of the piston 12 as trigger means.

On the front side of the piston 12, there is attached a pin 9 which passes through the orifice 4 with a sufficient space. The pin 9 is for adjusting the acceleration of the piston 12,
Its outer shape is appropriately shaped so as to obtain desired acceleration characteristics. Incidentally, in the example shown in FIG. 1, it has a conical shape. An O-ring for maintaining airtightness with the inner wall of the cylinder is fitted on the outer periphery of the piston 12, and an O-ring is appropriately fitted on a portion that needs to maintain airtightness at a connecting portion of each member. Omitted.

A pusher 21 is attached to the outer end of the piston rod 8, that is, the end on the end plate 7 side with a head cap 20 interposed therebetween. Pusher 21
A driven body such as a dummy doll is attached to the camera.

A low-speed test fluid cylinder 47 capable of pushing the piston 12 through the orifice 4 is provided in the load-side cylinder 2, which is a feature of the present invention. Low-speed test fluid cylinder 47
The base end is fixed to the center on the inner surface side of the end plate 3 of the load side cylinder 2 and extends parallel to the longitudinal direction of the load side cylinder 2. The low speed test fluid cylinder 47 is, for example, an oil cylinder. When the oil is supplied and discharged from the oil supply passage 49 at an appropriate pressure, the internal piston moves back and forth, and the piston rod 48 moves forward and backward. It is like this.

The low-speed test fluid cylinder 47 is pressed so that the piston of the low-speed test fluid cylinder 47 can push the piston 12 provided in the set-side cylinder 1.
Piston rod 48 faces the piston 12 in the set side cylinder 1. Actually, the piston rod 4
Reference numeral 8 is opposed to the tip end surface of the pin 9 fixed to the piston 12 in the set side cylinder 1. In addition, one end of the sleeve 23 is fitted and fixed to the tip of the piston rod 48 so that the tip of the piston rod 48 and the tip of the pin 9 are securely in contact with each other. The tip of the pin 9 can be fitted into the pin.

As in the conventional example, the set-side cylinder 1
Is supplied with a gas (for example, nitrogen gas) at a pressure P1 via an appropriate valve and a gas supply passage. Assuming that the area of the front surface (right side in FIG. 1) of the piston 12 is S3, the rear surface of the piston 12, that is, the area S1 on the side receiving the gas pressure P1 is S1 = S3-S. Therefore, the piston 12
Is pressed toward the orifice plate 5 with a pressing force of P1 × S1 = P1 × (S3-S). In the center of the front surface of the piston 12, the insert piston 1
1 is raised, and the raised surface is pressed against the periphery of the orifice 4 of the orifice plate 5 by the above-mentioned pressing force, so that a flat ring surrounded by the piston 12, the orifice plate 5, and the inner wall of the cylinder. Shaped space 6
5 are formed. This space 65 communicates with a trigger pressure supply passage 62 having a valve.

As shown in FIG. 1, the piston 12 is pressed against the orifice plate 5, and the piston 12 closes the orifice 4 to supply air at a pressure P2 to the load side cylinder 2. Assuming that the opening area of the orifice 4 is S2, the pressing force applied to the piston 12 through the orifice 4 is P2 × S2. Therefore, this pressing force P2 × S2
And the pressing force P1 × S1 is balanced, and P1 × S1 is actually set slightly larger than P2 × S2, and the state in which the piston 12 is pressed by the orifice plate 5 is maintained.

Next, the pressure P from the trigger pressure supply passage 62
3. Air and other gases are supplied. As described in the conventional example, the pressure P3 is applied to the space 65. When the area of the space 65 with respect to the piston 12 is S4, a pressing force of P3 × S4 is added to the piston 12. That is, the piston 12 has P1 × S
The one where the pressing force was applied in the relation of P2 × S2,
A pressing force is applied in a relationship of P1 × S1 to P2 × S2 + P3 × S4, and the balance relationship is broken, and the piston 12 is moved rightward in the drawing. When the piston 12 moves slightly to the left in the figure, the piston 1 moves through the orifice 4.
The pressure P2 is applied to the entire surface of the piston 2 and a large pressing force is applied to move the piston 12 at high speed.

Since the pressure P2 is set to be several times higher than the pressure P1, a large thrust is generated in the piston 12 and the piston rod 8 at the moment when the trigger pressure P3 is applied, and the piston 12 and the piston rod 8 are generated. 8 moves to the left in the figure at high speed. A dummy doll is attached to the pusher 21 at the tip of the piston rod 8, and a steering shock test can be performed when the dummy collides with the steering wheel of the automobile. Thus, similarly to the conventional example described above, various other so-called dynamic tests can be performed. After the completion of the dynamic test, the valve of the set-side cylinder 2 is opened to bring the interior of the set-side cylinder 2 to atmospheric pressure.
Therefore, the piston 12 can be automatically returned to the original position shown in FIG. 1 by this pressing force.

When the dynamic test is performed, the low-speed test fluid cylinder 47 does not operate at all and the pin 9 is moved to the piston rod 4 on the low-speed test fluid cylinder 47 side.
8 and the sleeve 23 are naturally separated from each other, and the presence of the low-speed test fluid cylinder 47 does not hinder the dynamic test.

In the above embodiment, if the low-speed test fluid cylinder 47 is driven, a so-called static test can be performed by moving the driven body at a low speed. That is, when oil is supplied at an appropriate pressure from the oil supply passage 49, the piston in the low-speed test fluid cylinder 47 moves, and the piston rod 48 integrated with the piston is pushed out of the cylinder 47, and the pin opposing the piston rod 48 is moved. When the piston 9 is pushed, the piston rod 8 integrated with the pin 9 is moved toward the outside of the set-side cylinder 1 at a relatively low speed. Therefore, if a head of a dummy doll is attached to the pusher 21 at the tip of the piston rod 8 and pressed against the headrest of the automobile, a load test of the headrest can be performed. It goes without saying that various other static tests can be performed.

When the static test is performed as described above, the gas in the set-side cylinder 1 is compressed by the piston 12 and resists the pressing force of the low-speed test fluid cylinder 47. Since 47 has a sufficiently large pressing force to oppose this resistance, it does not hinder the static test. The return of the piston 12 after the end of the static test is also automatically performed by the pressing force of P1 × S1 applied to the set-side cylinder 1. As can be understood from the above description, once the gas pressure P1 of the set-side cylinder 1 is set, the valve is kept closed by closing the valve.
Therefore, the valve on the set-side cylinder 1 side is opened and closed when the setting of the gas pressure P1 is changed.

2 to 4 show examples of various tests that can be performed using the impact test cylinder according to the present invention. In the example of FIG. 2, the dummy doll 50 is mounted on the pusher 21 at the tip of the piston rod 8 and moved at a high speed to collide with the steering wheel 51 of the automobile. It is an example of a dynamic test for testing the safety of a vehicle.

FIG. 3 shows a state in which the dummy 52 of the leg of the human body is mounted on the pusher 21 at the tip of the piston rod 8 and moved at a high speed. Board 53
Another example of a dynamic test for testing the safety of a test is shown.

FIG. 4 shows a pressing member 54 of an appropriate shape mounted on the pusher 21 at the tip of the piston rod 8, which is moved at a low speed by the driving of the low-speed test fluid cylinder 47 to reduce the headrest and the backrest of the automobile. An example of a static test in which a load resistance test is performed by pressing against a door, a door, and other places is shown.

[0032]

According to the first aspect of the present invention, the load side cylinder to which a constant gas pressure is applied, the set side cylinder to which a gas pressure lower than the gas pressure of the load side cylinder is applied, and the load side cylinder An orifice plate defining an orifice for partitioning the set-side cylinder and communicating the load-side cylinder and the set-side cylinder, and a piston slidably provided in the set-side cylinder and integrally having a piston rod. The area of the orifice is formed smaller than the area of the tip of the piston so that the piston closes the orifice so that the pressing force of the load side cylinder and the set side cylinder due to gas pressure can be balanced. , By applying trigger pressure to the tip surface of the piston with trigger means Moving the piston, applying gas pressure of the load side cylinder to the entire surface of the piston, moving the piston at a high speed, and applying an impact to the subject by the movement of the piston. Since a low-speed test fluid cylinder capable of pushing the piston through the orifice is provided in the side cylinder, both a high-speed test called a dynamic test and a low-speed test called a static test can be used.

According to the second aspect of the present invention, in the first aspect of the present invention, the low-speed test fluid cylinder is configured such that the piston of the low-speed test fluid cylinder can press a piston provided in the set-side cylinder. Because the piston rod of the fluid cylinder and the piston in the set-side cylinder are opposed to each other, the piston in the set-side cylinder separates from the piston rod of the low-speed test fluid cylinder during the dynamic test. It does not hinder dynamic testing.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of an impact test cylinder according to the present invention.

FIG. 2 is a side view conceptually showing a usage example of the impact test cylinder according to the present invention.

FIG. 3 is a side view conceptually showing another usage example of the impact test cylinder according to the present invention.

FIG. 4 is a side view conceptually showing still another example of use of the impact test cylinder according to the present invention.

FIG. 5 is a sectional view showing an example of a conventional impact test cylinder.

FIG. 6 is a sectional view showing one mode of operation of a conventional impact test cylinder.

FIG. 7 is a sectional view showing another mode of operation of the conventional impact test cylinder.

FIG. 8 is a sectional view showing still another mode of operation of the conventional impact test cylinder.

[Explanation of symbols]

 1 Set side cylinder 2 Load side cylinder 3 Orifice 5 Orifice plate 8 Piston rod 10 Valve as trigger means 12 Piston 47 Low speed test fluid cylinder 48 Piston

Claims (2)

[Claims] 1. A load-side cylinder to which a constant gas pressure is applied, a set-side cylinder to which a gas pressure lower than the gas pressure of the load-side cylinder is applied, and a load-side cylinder and a set-side cylinder are partitioned and loaded. An orifice plate formed with an orifice for communicating the cylinder with the set-side cylinder; and a piston slidably provided in the set-side cylinder and integrally having a piston rod. The pressing force of the gas pressure between the load side cylinder and the set side cylinder can be balanced with the piston closed with the orifice formed so as to be smaller than the area of the tip, and a trigger pressure is applied to the tip face of the piston. To disturb the balance of the pressing force to move the piston, An impact test cylinder provided with a trigger means for applying a gas pressure of a load side cylinder to the entire surface to move a piston at a high speed and to apply an impact to a subject by the movement of the piston, wherein the load side cylinder is provided. An impact test cylinder, wherein the low speed test fluid cylinder is provided in the inside and capable of pushing the piston through the orifice. 2. The piston of a low-speed test fluid cylinder,
2. The impact test cylinder according to claim 1, wherein the piston rod in the set-side cylinder and the piston rod of the low-speed test fluid cylinder face each other so that the piston provided in the set-side cylinder can be pushed.