JP2010008405A - Shock testing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a testing device that exerts impact acceleration on a test piece, using a simple constitution. <P>SOLUTION: The test piece TP is fixed to a low end of a hydraulic cylinder 10. An upper oil chamber 15 in the hydraulic cylinder 10 is connected to a tank 7 via a flow rate regulating valve 6, and a lower oil chamber 16 is connected to an accumulator 3. With the flow-rate regulating valve 6 in a closed state, pressure oil from a hydraulic pump 4 is accumulated in the accumulator 3, in advance. When the flow-rate regulating valve 6 is opened in this state, a piston 13 rapidly rises due to oil pressure from the accumulator 3, and impact acceleration acts on the test piece TP. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an impact test apparatus that applies impact acceleration to a test body.

  As this type of test apparatus, for example, an apparatus in which a vehicle is moved to load an impact acceleration is known (see, for example, Patent Document 1). In the apparatus described in Patent Document 1, the vehicle is fixed on a carriage that can move along a predetermined track, and the carriage is moved at a predetermined speed to apply an impact acceleration to the vehicle.

JP 2003-329538 A

  However, the device described in Patent Document 1 is large-scale, and a large amount of space is required to configure the device.

(1) An impact test apparatus according to the invention of claim 1 includes a cylinder rod driven by pressure oil, a hydraulic cylinder that moves a test body together with the cylinder rod to give an impact acceleration, and the test is started when the test is started. Drive pressure supply means for supplying a predetermined volume of drive pressure oil to the hydraulic cylinder, and drive pressure oil control means for supplying the drive pressure oil from the drive pressure supply means to the hydraulic cylinder.
(2) The invention of claim 2 is the impact test apparatus according to claim 1, wherein the driving pressure supply means is an accumulator in which the driving pressure oil is accumulated in advance.
(3) The invention of claim 3 is the impact test apparatus according to claim 2, wherein the hydraulic cylinder is formed to face the first oil chamber via a first oil chamber and a piston, A second oil chamber having a pressure receiving area smaller than that of the first oil chamber; a communication passage that communicates the first oil chamber and the second oil chamber; and the accumulator includes the second oil chamber When the accumulator accumulates the drive pressure oil, the drive pressure oil of the accumulator is introduced from the second oil chamber into the first oil chamber via the communication passage. The drive pressure oil control means is an open / close valve that communicates the first oil chamber to the low pressure side in the open position, and the impact acceleration test is performed by using the open / close valve to transfer the pressure oil in the first oil chamber to the low pressure. It is characterized in that it is configured to start by leading to the side.
(4) The invention of claim 4 is the impact test apparatus according to claim 2 or 3, further comprising pressure accumulation adjusting means for adjusting the pressure of the pressure accumulation oil accumulated in the accumulator.
(5) The invention of claim 5 is the impact test apparatus according to any one of claims 1 to 4, wherein damping is performed while the specimen is moved by a predetermined distance by inertia force when the hydraulic cylinder stops. And a damping mechanism for stopping the operation.
(6) According to a sixth aspect of the present invention, in the impact test apparatus according to the fifth aspect, the test body is connected to the cylinder rod via the damping mechanism, and the damping mechanism is configured to perform the inertial force at the end of the test. A damping rod that moves together with the test body, and a hydraulic damping force applying means that applies a hydraulic damping force to the damping rod when the damping rod moves are provided.
(7) A seventh aspect of the present invention is the impact test apparatus according to the fifth or sixth aspect, wherein the damping attenuation provided by the damping mechanism is set so as to stop the specimen at a substantially constant deceleration. It is characterized by that.
(8) According to an eighth aspect of the present invention, in the impact test apparatus according to the sixth aspect, the hydraulic damping force applying means includes a discharge side oil chamber that discharges oil as the damping rod moves, and the discharge side Oil introduced from the oil chamber to the inlet side, an inflow passage through which oil flows from the discharge side oil chamber to the introduction side oil chamber, and oil from the discharge side oil chamber to the inflow passage And a damping oil passage disposed so that an effective area of the oil passage decreases as the damping rod moves.
(9) The invention of claim 9 is the impact test apparatus according to claim 8, wherein the damping oil passage is configured such that an effective passage area of the damping oil passage is reduced at a reduction rate corresponding to the movement of the damping rod. Is provided.
(10) The invention of claim 10 is the impact test apparatus according to claim 9, wherein the effective passage area of the damping oil passage is determined so that the damping rod stops at a constant deceleration at the end of the test. It is provided so that it may decrease corresponding to.

  According to the present invention, since the hydraulic cylinder is driven by the drive oil having a predetermined capacity to give acceleration to the test body, the impact acceleration can be applied to the test body with a simple configuration.

The figure which shows schematic structure of the impact test apparatus which concerns on the 1st Embodiment of this invention. The figure which shows an example of the operation characteristic by the impact test apparatus of FIG. The figure which shows typically the structure of the damping mechanism of the impact test apparatus which concerns on the 2nd Embodiment of this invention. The figure which shows in detail the structure of the damping mechanism of the impact test apparatus which concerns on the 3rd Embodiment of this invention. The figure explaining the mechanism which makes the relative rotation angle position between a cylinder (inner cylinder) and a cylinder tube (outer cylinder) variable. The figure explaining operation | movement of the damping mechanism of FIG. FIG. 5 is a development view of a cylinder showing a plurality of damping oil passages of the damping mechanism of FIG. 4. The figure explaining operation | movement of the damping mechanism of FIG.

-First embodiment-
A first embodiment of an impact test apparatus according to the present invention will be described below with reference to FIGS. FIG. 1 is a diagram showing a schematic configuration of an impact test apparatus according to a first embodiment of the present invention. In this impact test apparatus, for example, it is evaluated whether or not internal components and units are damaged by a large acceleration (impact acceleration) generated at the time of a car collision or the like.

As shown in FIG. 1, a hydraulic cylinder 10 is attached to the frame 1 of the test apparatus in a substantially vertical direction. The hydraulic cylinder 10 includes a substantially cylindrical cylinder tube 11 erected on the upper surface of the frame 1, and a cylinder that extends through the upper end surface and the lower end surface of the cylinder tube 11 so as to move up and down in the cylinder tube 11. Rod (piston rod) 12. A piston 13 is formed at the center of the cylinder rod 12, and cushion portions 14 are provided at the upper and lower ends of the cylinder tube 11 for reducing the impact when the piston is stopped.

  In the cylinder tube 11, an upper oil chamber 15 is formed above the piston 13, and a lower oil chamber 16 is formed below the piston 13. The upper oil chamber 15 and the lower oil chamber 16 communicate with each other through a communication passage 20. The pressure receiving area A1 of the piston 13 in the upper oil chamber 15 is larger than the pressure receiving area A2 of the lower oil chamber 16, and A2 is about 0.7 to 0.9 times A1.

  An attachment frame 17 is fixed to the lower end portion of the cylinder rod 12, and the test body TP is integrally fixed to the attachment frame 17. The test body TP moves up and down by driving the hydraulic cylinder 10, and the acceleration acting on the test body TP is detected by the accelerometer 2.

  A pressure oil inflow portion 18 is provided at the lower end of the cylinder tube 11, and the lower oil chamber 16 communicates with the accumulator 3 through the pressure oil inflow portion 18. The accumulator 3 is connected to the hydraulic pump 4 via the pipe line L <b> 1, and the pressure oil from the hydraulic pump 4 is accumulated in the accumulator 3. The capacity of the accumulator 3 is set to a value corresponding to 30 to 40% of the moving amount of the piston 13 (effective stroke of the piston 13) during the test. A pressure setting device 5 such as a relief valve is connected to the pipe L1, and the pressure of the accumulated oil in the accumulator 3 is set to a predetermined value by the pressure setting device 5.

  A pressure oil outflow portion 19 is provided at the upper end portion of the cylinder tube 11, and the upper oil chamber 15 communicates with the flow rate adjustment valve 6 through the pressure oil outflow portion 19. The flow rate adjusting valve 6 is connected to the tank 7 via a pipe line L2. The flow rate adjusting valve 6 is opened and closed by a signal from the controller 8 to allow or prohibit the flow of pressure oil from the upper oil chamber 15 to the pipe line L2. When the flow rate adjustment valve 6 is opened, the flow of return oil from the upper oil chamber 15 to the tank 7 is throttled by the flow rate adjustment valve 6.

The main operation of the first embodiment will be described.
When performing an impact test, first, the hydraulic pump 4 is driven with the flow rate adjustment valve 6 closed. As a result, the pressure oil from the hydraulic pump 4 is accumulated in the accumulator 3. At this time, the pressure oil flows into the upper oil chamber 15 through the communication passage 20, and the upper oil chamber 15 and the lower oil chamber 16 have the same pressure. Since the pressure receiving area A1 of the upper oil chamber 15 of the piston 13 is larger than the pressure receiving area A2 of the lower oil chamber 16, the piston 13 descends to the lowest position due to the pressure difference.

  In this state, for example, when a test start switch is operated, the flow rate adjustment valve 6 is opened by a signal from the controller 8. As a result, the pressure oil in the oil chamber 15 flows into the tank 7, the cylinder rod 12 rises due to the pressure difference between the oil chambers 15 and 16, and the pressure oil in the upper oil chamber 15 is returned to the tank 7. FIGS. 2A to 2C are diagrams showing the relationship between the displacement d, the moving speed v, and the acceleration a of the cylinder rod 12 (piston 13) with respect to the elapsed time t after the flow rate adjusting valve 6 is opened. When the flow rate adjusting valve 6 is opened, the accumulated energy of the accumulator 3 is suddenly released. Therefore, as shown in FIG. 2, the acceleration a of the cylinder rod 12 rapidly increases due to the pressure oil from the accumulator 3, and the acceleration a reaches the maximum at time t1. a1.

  Thereafter, as the accumulated oil in the accumulator 3 decreases, the acceleration a decreases. When all accumulated energy is released at time t2, the acceleration a becomes zero. At this time, the moving amount of the cylinder rod 12 is 30 to 40% of the total moving amount, and the moving speed v of the cylinder rod 12 is maximum. After the time point t2, the acceleration a becomes negative, and the cylinder rod 12 is raised by the inertial force while being decelerated by the throttle action of the flow rate adjusting valve 6. Although the negative acceleration reaches a2 at the maximum at time t3, the cylinder rod 12 slowly decelerates due to the damper effect caused by the restriction of the flow regulating valve 6, so the magnitude of the negative acceleration a2 (absolute value) is smaller than a1.

  When a predetermined time t4 has elapsed after the flow rate adjusting valve 6 is opened, the flow rate adjusting valve 6 is closed by a signal from the controller 8. The predetermined time t4 is set to a time earlier than the time when the cylinder rod 12 collides with the upper end portion of the piston tube 11. When the flow rate adjustment valve 6 is closed, a negative acceleration a rises, but at the time t4, the cylinder rod 12 has already been sufficiently decelerated, so the rise of the acceleration a is small. For this reason, the cylinder rod 12 stops quickly, without the big impact at the time of a stop acting on the test body TP. Note that the amount of movement of the cylinder rod 12 may be detected, and the flow rate adjusting valve 6 may be closed according to the amount of movement of the cylinder rod 12.

  As described above, the impact acceleration a (= a1) can be applied to the test body TP, and it can be evaluated whether or not the test body TP is damaged by the impact acceleration a1. In order to increase the impact acceleration a1, the set pressure of the pressure setting device 5 is increased to increase the pressure of the pressure oil accumulated in the accumulator 3, or the mass of the mounting frame 7 and the cylinder rod 12 is reduced. Good.

According to the present embodiment, the following operational effects can be achieved.
(1) A test body TP is provided integrally with the hydraulic cylinder 10, and a predetermined amount of accumulated oil accumulated in the accumulator 3 in advance by switching the flow rate adjusting valve 6 is supplied to the hydraulic cylinder 10 to drive the cylinder rod 12. did. As a result, the test specimen TP can be accelerated rapidly with a short approaching distance, and the test specimen TP can be gently stopped at a relatively short distance, with a simple configuration without requiring much space for configuring the apparatus. Impact acceleration can be applied to the test body TP. That is, immediately after the start of the test, the specimen TP can be rapidly accelerated by the accumulated energy of the accumulator 3, and after all the accumulated energy has been released, the specimen TP can be slowly decelerated by the throttling action of the flow regulating valve 6. it can.

(2) Since the driving pressure is supplied to the hydraulic cylinder 10 using the accumulator 3 having a capacity equivalent to 30 to 40% of the moving amount of the piston 13, the deceleration zone can be made longer than the acceleration zone, and the cylinder rod The magnitude of a negative acceleration (deceleration) a2 acting on the pressure 12 can be made smaller than the magnitude of a positive acceleration a1 (FIG. 2C). For this reason, it is possible to prevent the occurrence of impact acceleration during deceleration, and the test body TP is loaded with impact acceleration only during acceleration, so that a good impact acceleration test can be performed.

  In order to make the maximum value of deceleration smaller than the maximum value of acceleration, the point that the driving force by the pressure oil supplied from the accumulator 3 and the resistance force when the cylinder rod 12 moves is balanced. What is necessary is just to determine the capacity | capacitance of the accumulator 3 so that it may become 1/2 or less of the rod effective moving amount | distance.

(3) The pressure receiving area A1 of the upper oil chamber 15 of the hydraulic cylinder 10 is made larger than the pressure receiving area A2 of the lower oil chamber 16, and the flow rate adjustment valve 6 is connected to the lower oil chamber 16 in communication with the upper oil chamber 15. The accumulators 3 are provided in communication with each other. As a result, when the accumulator 3 is accumulated with the driving pressure, the cylinder rod 12 is automatically lowered, and the shock acceleration can be applied to the test body TP simply by opening the flow rate adjusting valve 6 in this state, so that the configuration is simple.

(4) Since the pressure of the accumulated oil in the accumulator 3 can be adjusted by the pressure setting device 5, the magnitude of the impact acceleration can be easily changed.

-Second Embodiment-
A second embodiment of the impact test apparatus according to the present invention will be described with reference to FIG. In the following description, differences from the first embodiment will be mainly described. The second embodiment is different from the first embodiment in the shape of the lower end portion of the hydraulic cylinder 10. That is, in the first embodiment, the test body TP is integrally provided through the mounting frame 17 at the lower end of the hydraulic cylinder 10, that is, the tip of the cylinder rod 12, but in the second embodiment, the hydraulic cylinder 10 A test body TP is provided at the lower end of the cylinder rod 12, that is, at the tip of the cylinder rod 12 through the damping mechanism 30 so as to be relatively movable.

  FIG. 3 is a diagram showing a configuration of a main part of the impact test apparatus according to the second embodiment, and mainly shows a configuration of the lower end portion of the cylinder rod 12 in a sectional view. Configurations other than those illustrated are the same as those in FIG. The damping mechanism 30 is configured by, for example, a hydraulic damper, and includes a damper case 31 attached to the lower end portion of the cylinder rod 12 and a damper rod 32 inserted into the damper case 31 so as to be movable up and down.

  The upper and lower ends of the damper rod 32 penetrate the upper and lower ends of the damper case 31 so as to be slidable. A cavity 121 is provided at the lower end of the cylinder rod 12, and the upper end of the damper rod 32 is inserted into the cavity 121. A test body TP is fixed to the lower end portion of the damper rod 32, and the test body TP moves integrally with the damper rod 32. A piston 33 is provided at the center of the damper rod 32, and oil chambers 34 and 35 are formed on the upper and lower sides of the piston 33, respectively.

  The upper end of the damper case 31 through which the damper rod 32 passes is sealed, and oil is sealed in the oil chambers 34 and 35. Oil passages 36 are formed in the damper case 31 at a plurality of locations in the circumferential direction so as to penetrate the side wall of the damper case 31, and the oil chamber 34 and the oil chamber 35 communicate with each other via the oil passage 36. The oil passage 36 constitutes a throttle of the damping mechanism 30.

A characteristic operation of the second embodiment will be described.
In the initial state, the damper rod 32 descends due to gravity, and the piston 33 is positioned at the lowermost part in the damper case 31. When the pressure oil from the accumulator 3 acts on the piston 13 (FIG. 1) of the hydraulic cylinder 10 by the start of the test, the cylinder rod 12 rises and the specimen TP also rises via the damper case 31 and the damper rod 32. At this time, there is no damping action, and impact acceleration acts on the specimen TP.

  Thereafter, when the cylinder rod 10 decelerates and stops, the damper rod 32 moves upward in the damper case 31 integrally with the test body TP by inertial force. At this time, since the oil flows from the oil chamber 34 to the oil chamber 35 through the oil passage 36 due to the movement of the piston 33, the test body TP is slowly stopped by the damping action by the oil flow.

  As described above, in the second embodiment, since the specimen TP is attached to the end of the hydraulic cylinder 10 via the damping mechanism 30, the acceleration when the specimen TP is decelerated and stopped is reduced by the damping action. Can do. Further, since the damper rod 32 relatively moves in the damper case 31, the stroke when the specimen TP is decelerated and stopped is lengthened, and the deceleration section of the cylinder rod 12 (FIG. 2C) can be shortened accordingly. it can. Since the acceleration at the time of deceleration stop can be reduced, it is also possible to perform an impact acceleration test using a testing machine having a high speed hydraulic cylinder such as a high speed tensile testing machine.

-Third embodiment-
An impact test apparatus according to a third embodiment will be described with reference to FIGS.
In the third embodiment, the damping effect of the damping mechanism of the second embodiment is improved. Differences from FIGS. 1 and 2 showing the first embodiment and FIG. 3 showing the second embodiment will be mainly described.

As shown in FIG. 4, the hydraulic damping mechanism 50 of the impact test apparatus according to the third embodiment is configured to include a damper case 51 and a damper rod 52 slidably provided in the damper case. Yes. A connection flange 52a is provided at the tip of the damper rod 52, and the attachment frame 17 shown in FIG. 1 is attached to the connection flange 52a.
Depending on the test body, the test body TP may be directly mounted on the damper rod 52 without using the mounting frame 17.

  The damper case 51 includes a cylinder rod connecting part (upper bearing) 51a screwed to the cylinder rod 12, a cylinder (inner cylinder) 51b screwed at one end to the cylinder rod connecting part 51a, and a cylinder (inner cylinder) 51b. A lower bearing 51c screwed to the other end of the cylinder 51 and a cylinder tube (outer cylinder) 51d covering the outer periphery of the cylinder 51b.

  The cylinder 51b has a cylindrical shape, and a throttle hole group 60 that constitutes an oil passage is provided on the peripheral wall. The throttle hole group 60 is a plurality of holes drilled in the peripheral wall so as to give the damper rod 52 damping damping. As shown also in FIG. 5, the cross-sectional shape of the inner peripheral surface of the outer cylinder 51d into which the cylinder 51b is inserted is not a perfect circle, but a cross-sectional shape in which a part is recessed. A damping passage 54 is formed between them.

  When the damper rod 52 moves in the cylinder by the inertial force at the end of the test, the oil in the upper chamber 53a of the damper rod piston 52a flows from the upper hole 60a of the throttle hole group 60 as shown in FIG. After passing through the damping passage 54, it flows from the lower hole 60b of the throttle hole group 60 into the lower chamber 53b of the damper rod piston 52a.

  The damping mechanism 50 according to the third embodiment is provided for the purpose of stopping the test body to which the impact acceleration is applied at a constant deceleration. That is, when the damper rod 52 moves upward due to the inertial force, the oil in the upper chamber (discharge side oil chamber) 53a of the damper rod piston 52a flows from the plurality of holes on the upper side of the throttle hole group 60 into the damping passage 54. Then, it flows into the lower chamber (introduction side oil chamber) 53b of the damper rod piston 52a through a plurality of holes on the lower side of the throttle hole group 60. When oil flows in such a path, the total cross-sectional area of the throttle hole 60 (hereinafter referred to as a damping path area) when flowing into the damping passage 54 from the upper chamber 53a dominates the deceleration of the damper rod 52. In the third embodiment, the throttle hole arrangement as described below is adopted, and damping is performed so that the damper rod 52 decelerates at a constant deceleration until it stops due to inertial force until the damper rod 52 starts moving. Set the path area.

  In the hydraulic damping mechanism, in order to stop the specimen at an equal deceleration, it is only necessary to obtain a certain hydraulic resistance force against a speed change during deceleration. Since the hydraulic resistance force by the restriction is proportional to the flow velocity of the flowing oil, the damping path area is increased in the region where the speed of the damper rod 52 is large, and the region where the speed of the damper rod 52 is reduced, that is, the test body is at the stop end. As it gets closer, the damping path area is reduced. Thereby, the flow velocity of the oil passing through the throttle hole group 60 can be made as constant as possible, so that a constant hydraulic resistance force can be obtained.

  In order to satisfy such a condition, when designing the arrangement of the throttle holes constituting the throttle hole group 60, the portion where the initial damping rod speed is high passes when oil flows into the damping passage 54 from the upper chamber 53a. Increase the number of throttle holes. In addition, in the portion where the initial damping rod speed is large, the pitch at which the throttle hole is effective in the damping rod moving direction is large, and in the vicinity of the end, the pitch at which the throttle hole is effective in the damping rod moving direction is small. The pitch. For example, when an object moves at a constant acceleration (deceleration), the speed is proportional to the square root of the distance from the stop position. Therefore, the plurality of throttle holes may be arranged so that the total sectional area of the holes effective for damping is proportional to the square root of the distance.

  The arrangement of the holes of the throttle hole group 60 for stopping the specimen as described above at a constant deceleration will be described. FIG. 7 is a developed view for explaining the arrangement of the holes of the throttle hole group 60, wherein 25 throttle holes are arranged in a 5 × 5 grid. The arrow direction in FIG. 7 is the damper rod moving direction. A position at which the damper rod 52 starts to move due to the inertial force is represented by reference numeral 52S, and a position at which the damper rod 52 stops is represented by reference numeral 52E. The five holes closed at the start position 52S are return passages that are opened when the damper rod 52 starts moving.

  When the damper rod 52 starts to move, that is, the damping path area at the position 52S is the total cross-sectional area of the throttle holes indicated by reference numerals 1-25. As the damper rod 52 moves, the throttle hole indicated by reference numeral 1 is first closed by the damper rod piston 52a, then the throttle hole indicated by reference numeral 2 is closed, and then the throttle hole indicated by reference numeral 3 is closed. It will be peeled off. At the stop position 52E, all the throttle holes are closed and stopped. Therefore, the damping path area gradually decreases corresponding to the position of the damper rod 52 so that the damping rod decelerates at a constant deceleration.

  The damping mechanism 30 of the second embodiment is also provided with an oil passage 36 (see FIG. 3) that gives damping damping, but does not stop the damper rod 32 at a constant deceleration.

  As described above, in the hydraulic damping mechanism 50 according to the third embodiment, the damping path area is variable in conjunction with the upward movement of the damper rod 52 so that the specimen is decelerated at a predetermined constant deceleration. It was. Further, in the hydraulic damping mechanism 50 of the third embodiment, the deceleration can be variably set in a plurality of stages. This will be described with reference to FIG.

  As shown in FIG. 5, the relative rotation angle between the cylinder 51b and the outer cylinder 51d can be changed by rotating the outer cylinder 51d with respect to the cylinder 51b by the handle 55. In the relative angular position of FIG. 5A, all of the throttle hole group 60 (typically indicated by reference numerals 60a1 to 60a5) faces the damping passage 54.

  In FIG. 5A, all 25 throttle holes (in FIG. 5A, five throttle holes 60a1 to 60a5 are shown as representatives) face the damping passage 54. When the outer cylinder 51d is rotated counterclockwise by the rotary handle 55 with respect to the cylinder 51b and the relative rotation angle position between the cylinder 51b and the outer cylinder 51d is as shown in FIG. The row (throttle hole 60a5 in FIG. 5B) does not face the damping path 54. For example, the five throttle holes denoted by reference numerals 5, 10, 15, 20, and 25 in FIG. 7 do not contribute to damping, and the damping path area at the start of the damping rod movement and the subsequent path area are reduced. That is, the deceleration increases.

For example, the graph of DC1 in FIG. 2C shows the cylinder rod deceleration when the graph is shown in FIG. 5A, and the graph of AC2 shows the cylinder rod deceleration when it is shown in FIG. 5B.
If the outer cylinder 51d is further rotated in the counterclockwise direction, a larger deceleration can be set.

  In the impact test apparatus according to the third embodiment described above, when the cylinder rod 12 stops at the stroke end and the application of impact acceleration to the specimen TP ends, the damping rod 52 starts to move upward by inertial force. To do. At this time, the oil in the pressure oil discharge side oil chamber 53a on the upper side of the piston of the damping rod 52 passes through the oil passage 60a on the upper side of the throttle hole group 60 and flows into the damping passage 54, and further on the lower side of the throttle hole group 60. Passes through the oil passage 60b and flows into the oil introduction side oil chamber 53b. The upper oil passage 60 a of the throttle hole group 60 is a damping oil passage through which oil is discharged from the discharge-side oil chamber 53 a to the damping passage 54, and the effective area contributing to damping decreases as the damping rod 52 moves. It is arranged to do. That is, in the third embodiment, the effective area of the damping oil passage 60a is set corresponding to the position of the damping rod 52 so that the damping rod 52 stops at a constant deceleration at the end of the impact acceleration test.

  Therefore, according to the impact test apparatus according to the third embodiment, the same effect as that of the second embodiment can be obtained, and the test body TP can be stopped at a constant deceleration, which is undesirable when stopped. There is no risk of applying an impact force to the specimen TP.

  As shown in FIG. 4 (or FIG. 6), if the oil passage 60b is arranged slightly above the lower limit position of the cylinder, the damper rod 52 will stop when it is lowered to a predetermined position when it stops at the lowest position. The flow path 54 is blocked from the introduction oil chamber 53b, and a hydraulic cushion effect is obtained by the oil confined in the gap. The hydraulic cushion described above is effective when there is a possibility that the damper rod 52 will collide at the lowermost end after dropping by its own weight after the wet specimen TP stops at the end of the test with a vertical impact test device. When the oil passage 60b is arranged at the lower end of the introduction oil chamber 53b, the hydraulic cushion effect cannot be obtained, and when the damper rod 52 descends, a collision between the lower limit position 51a and the metal parts occurs, and a large acceleration is instantaneously generated. May act on the specimen TP.

It should be noted that the above embodiment can be modified as follows.
(1) A predetermined amount (corresponding to 30 to 40% of the moving distance of the piston 13) of driving pressure oil is accumulated in the accumulator 3 and supplied to the hydraulic cylinder 10, but the means for supplying the driving pressure is an accumulator. It is not restricted to the structure using.

(2) By opening the flow rate adjusting valve 6, the pressure oil accumulated in the accumulator 3 is supplied to the cylinder 10, but means for starting the supply of the driving pressure oil is not limited to this. For example, in the pipe L2, a fixed throttle is provided in place of the flow rate adjusting valve 6, and an open / close valve is provided between the pressure oil inflow portion 18 of the cylinder 10 and the accumulator 3, and the accumulator 3 is opened by opening the open / close valve. You may make it supply the pressure oil accumulate | stored in to the cylinder 10. FIG.

(3) The flow rate adjusting valve 6 is a valve configuration having metering performance so as to give a predetermined throttling effect when opened, but is a so-called mere on-off valve having a sufficiently large passage area at the open position, A fixed or variable aperture that gives a predetermined aperture effect may be arranged.
(4) The acceleration waveform applied to the specimen may be changed by changing the opening over time without simply turning on and off the flow regulating valve 6.

(5) The pressure receiving area A1 of the upper oil chamber 15 (first oil chamber) of the hydraulic cylinder 10 is made smaller than the pressure receiving area A2 of the lower oil chamber 16 (second oil chamber), and the piston 13 is started at the start of the test. Is positioned at the bottom, but these device configurations are merely examples.

(6) Although the pressure of the pressure accumulation oil of the accumulator 3 can be adjusted by the pressure setting device 5, the pressure accumulation adjusting means is not limited to this.
(7) Although the damping mechanism 30 or 50 is configured by a hydraulic damper (FIGS. 3 and 4), the test body TP may be attached to the end of the hydraulic cylinder 10 via another damping mechanism.

(8) In the third embodiment, the arrangement of the damping oil passage 60 is determined so that the damping rod 52 stops at a constant deceleration. However, in the present invention, the arrangement of the damping oil passage 60 may be determined so that the degree of reduction in the effective area of the damping oil passage 60 becomes a predetermined deceleration characteristic. In other words, in order to stop the damping rod 52 at an ideal constant deceleration, it is necessary to continuously change the effective cross-sectional area of the throttle hole 60. However, the present invention provides a damping rod at an ideal constant deceleration. It is not necessary to stop 52, and design with an ideal equal deceleration as a target value may be performed. Therefore, you may change the diameter of the hole 60 corresponding to the moving direction of a damping rod. Alternatively, although the hole has a circular shape, it may have any shape such as an ellipse, a long hole, or a spiral hole.

(9) The damping mechanism 50 is an example, and any damping mechanism 50 may be used as long as it provides damping damping that stops the specimen moving with the inertial force at an almost constant deceleration at the end of the impact test. For example, the upper oil chamber 53a of the damper rod piston 52a is connected to an external pipeline, and the metering characteristic in which the opening degree is reduced in accordance with the amount of movement of the damper rod 52 is provided in the pipeline, and the constant deceleration It is also possible to provide a configuration such as a flow rate adjusting valve that provides damping damping.

  As described above, the present invention is not limited to the impact test apparatus of the embodiment as long as the features and functions of the present invention can be realized.

3 Accumulator 5 Pressure setter 6 Flow rate adjusting valve 10 Hydraulic cylinder 11 Cylinder rod 12 Cylinder tube 15 Upper oil chamber 16 Lower oil chamber 30, 50 Damping mechanism 51 Damper case 51b Cylinder 51d Cylinder tube 54 Damping passage 60 Restriction hole (restriction hole) group)

Claims (10)

A hydraulic cylinder having a cylinder rod driven by pressure oil, and moving the test body together with the cylinder rod to give an impact acceleration;
Drive pressure supply means for supplying a predetermined volume of drive pressure oil to the hydraulic cylinder as the test starts,
An impact test apparatus comprising: drive pressure oil control means for supplying drive hydraulic oil from the drive pressure supply means to the hydraulic cylinder. The impact test apparatus according to claim 1,
The impact test apparatus according to claim 1, wherein the drive pressure supply means is an accumulator in which the predetermined capacity of drive pressure oil is accumulated. The impact test apparatus according to claim 2,
The hydraulic cylinder includes a first oil chamber, a second oil chamber formed opposite to the first oil chamber via a piston, and having a pressure receiving area smaller than that of the first oil chamber; A first oil chamber and a communication passage communicating the second oil chamber;
The accumulator is provided in communication with the second oil chamber;
When accumulating the drive pressure oil in the accumulator, the drive pressure oil of the accumulator is introduced from the second oil chamber to the first oil chamber via the communication passage,
The driving pressure oil control means is an on-off valve that communicates the first oil chamber to the low pressure side in an open position,
The impact test apparatus is configured to start the impact acceleration test by guiding the pressure oil in the first oil chamber to the low pressure side by the on-off valve. The impact test apparatus according to claim 2 or 3,
An impact test apparatus, further comprising pressure accumulation adjusting means for adjusting the pressure of the pressure accumulation oil accumulated in the accumulator. In the impact test device according to any one of claims 1 to 4,
An impact test apparatus, further comprising a damping mechanism for damping and stopping the specimen while moving the specimen by a predetermined distance by an inertial force when the hydraulic cylinder stops. The impact test apparatus according to claim 5,
The test body is connected to the cylinder rod via the damping mechanism;
The damping mechanism is
A damping rod that moves together with the specimen under inertial force at the end of the test;
An impact test apparatus comprising: a hydraulic damping force applying unit that applies a hydraulic damping force to the damping rod when the damping rod moves. The impact test apparatus according to claim 5 or 6, wherein the damping attenuation given by the damping mechanism is set so as to stop the test body at substantially equal deceleration. The impact test apparatus according to claim 6,
The hydraulic damping force applying means is
A discharge-side oil chamber that discharges oil as the damping rod moves;
An introduction side oil chamber into which oil discharged from the discharge side oil chamber is introduced;
An inflow passage through which oil flows from the discharge side oil chamber to the introduction side oil chamber;
An oil passage for discharging oil from the discharge-side oil chamber to the inflow passage, and a damping oil passage disposed so that an effective area of the oil passage decreases as the damping rod moves. An impact test device characterized by The impact test apparatus according to claim 8,
The impact testing apparatus according to claim 1, wherein the damping oil passage is provided so that an effective passage area of the damping oil passage is reduced at a decreasing rate corresponding to the movement of the damping rod. The impact test apparatus according to claim 9, wherein
The impact test apparatus according to claim 1, wherein the effective passage area of the damping oil passage is provided so as to decrease corresponding to the position of the damping rod so that the damping rod stops at a constant deceleration at the end of the test.

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