Test equipment

Abstract

To provide a test device that can reduce power consumption. [Solution] The test apparatus 1 comprises a linear motor vibrator 3 that generates vibration when power is supplied, a relay means 4 that transmits vibration from the linear motor vibrator 3 to a shock absorber 100, and a braking means 6. The braking means 6 stops the movement of the rod 42 of the relay means 4, so that even if the power supply to the linear motor vibrator 3 is terminated, the position at the end of the vibration can be maintained, and the power consumption when maintaining the position at the end of the vibration can be reduced.

Description

Technical Field

[0001] The present invention relates to a test apparatus that imparts vibrations to a specimen to measure its characteristics.

Background Art

[0002] Conventionally, a test apparatus has been proposed that tests the performance and durability of a suspension by vibrating it with a vibrator while applying a load to the suspension (see, for example, Patent Document 1). In the test apparatus described in Patent Document 1, a shock absorber is linked to the tire side by a slide shaft to form a suspension, and the tire is vibrated by a vibrator to test the performance and durability of the suspension.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The test apparatus described in Patent Document 1 uses a hydraulic actuator as the exciter. However, hydraulic actuators require a large amount of power to supply pressure from the hydraulic source. Furthermore, when used for applications such as HILS (Hardware-In-the-Loop Simulation), real-time response control with minimal delay is required, which is difficult to achieve with hydraulic actuators. Therefore, in response to demands for energy saving and improved controllability, electrically operated actuators such as linear motors and electrodynamic actuators (hereinafter referred to as "electrically operated vibration means") have sometimes been used. In the case of such electrically operated actuators, although the power consumption during excitation (vibration) is smaller than that of hydraulic actuators, it is necessary to maintain the power supply in order to maintain the position at the end of vibration. This has the disadvantage that power consumption continues to be generated when maintaining the position in the vibration-stopped state, resulting in a non-energy-saving state.

[0005] The objective of the present invention is to provide a testing apparatus that can reduce power consumption. [Means for solving the problem]

[0006] The present invention is a testing apparatus for measuring the characteristics of a test specimen by applying vibration in a vibration direction along the vertical direction, and is characterized by comprising: an electric excitation means that generates vibration when power is supplied; a relay means that transmits vibration by being connected to the output of the excitation means and one end of the test specimen in the vibration direction; and a braking means that stops movement in the vibration direction with at least one of the output unit and the relay means as the target for braking.

[0007] According to the present invention as described above, the braking means stops the movement of at least one of the output section and relay means of the excitation means, thereby maintaining the position at the end of vibration even when the power supply to the electric excitation means is terminated, and reducing the power consumption when maintaining the position at the end of vibration.

[0008] In this case, the test apparatus of the present invention preferably has a relay body portion extending along a plane intersecting the vibration direction, and a plurality of rods connected to the relay body portion that extend along the vibration direction and are guided along the vibration direction, and the brake means preferably holds the outer circumferential surface of the rods. With such a configuration, there is no need to form a held portion in the excitation means, and the excitation means can be easily standardized among test apparatuses of different specifications.

[0009] Furthermore, in the test apparatus of the present invention, the plurality of rods preferably include four rods arranged in a square shape, and the braking means preferably holds each of the two rods arranged on the diagonals of the square. With such a configuration, when the position at the end of vibration is maintained by the braking means, tilting of the relay unit body can be suppressed.

[0010] Furthermore, in the test apparatus of the present invention, the outer circumferential surface of the rod has a plurality of planar portions extending along a plane including the vibration direction, and a connecting surface connecting two of the planar portions, and it is preferable that the braking means holds the connecting surface. With such a configuration, the area to be braked and the area to be guided during vibration in the vibration direction can be made independent on the outer circumferential surface of the rod. As a result, even if changes such as scratches or deformation occur on the outer circumferential surface of the rod due to repeated braking, it is less likely to affect the guidance by the guide portion, and the rod can be guided smoothly.

[0011] Furthermore, the test apparatus of the present invention further comprises a control means for controlling the excitation means, and the braking means comprises a biasing means for generating a biasing force in the direction toward the brake target, and a release force generating means for generating a release force opposite to the biasing force, and it is preferable that the control means drives the excitation means when it receives a release completion signal from the braking means indicating that the holding has been released. With such a configuration, even if a malfunction occurs in the release force generating means and no release force is generated, the biasing means can maintain the cessation of movement. In addition, if the brake is not released due to some malfunction, the excitation means can be prevented from being driven.

[0012] Furthermore, in the test apparatus of the present invention, the braking means preferably includes a pair of clamping parts that clamp the object to be braked by approaching each other, and a sensor that detects the distance between the pair of clamping parts, and the control means preferably receives a signal from the sensor as the release completion signal, indicating that the distance between the pair of clamping parts has exceeded a predetermined value. With such a configuration, the excitation means can be prevented from being driven when the clamping by the pair of clamping parts is not released. In addition, the excitation means can be prevented from being driven even if a malfunction occurs in the sensor or if there is a problem with communication between the sensor and the control unit. [Effects of the Invention]

[0013] According to the test apparatus of the present invention, power consumption can be reduced. [Brief explanation of the drawing]

[0014] [Figure 1] This is a front view showing a test apparatus according to an embodiment of the present invention. [Figure 2] This is a cross-sectional view showing the vibration means of the test apparatus. [Figure 3] A cross-sectional view showing the relay means of the test apparatus. [Figure 4] A cross-sectional view showing the relay means of the test apparatus. [Figure 5]This is a cross-sectional view showing the state in which the braking means of the test device has stopped moving. [Figure 6] This is a cross-sectional view showing the state in which the brake means of the test device has been released. [Figure 7] This is a perspective view showing the holding means of the test apparatus. [Modes for carrying out the invention]

[0015] Embodiments of the present invention will be described with reference to the drawings. As shown in Figure 1, the test apparatus 1 of this embodiment uses a shock absorber 100 as a test specimen, applies vibration along the longitudinal direction (extension direction) of the shock absorber 100, and measures various characteristics of the shock absorber 100 during vibration.

[0016] Examples of characteristics of the shock absorber 100 to be measured include the extension and retraction speed of the shock absorber 100, the piston load, and the displacement in the direction of vibration. Furthermore, positional and temporal characteristics (displacement, velocity, acceleration) can be converted to other characteristics by measuring the time change of one characteristic, and the characteristics (physical quantities) to be directly measured can be selected as appropriate. That is, an appropriate type of sensor can be used depending on the characteristics of the shock absorber 100 and the test conditions. In this embodiment, a linear encoder 35 is used as described later, but other sensors may be used instead or in addition. Also, the test specimen may be the shock absorber 100 alone, or it may be the shock absorber 100 combined with other components such as a spring.

[0017] The test apparatus 1 comprises a main frame 2, a linear motor exciter 3 as an electrically operated vibration excitation means, a relay means 4, a holding means 5, a braking means 6, and a control unit (not shown). Hereafter, the horizontal plane will be referred to as the XY plane and the vertical direction as the Z direction, and the up and down directions in the Z direction will be simply referred to as up and down.

[0018] The body frame 2 includes a lower frame 21, an upper frame 22, and a lifting cylinder 23 that connects the lower frame 21 and the upper frame 22.

[0019] The lower frame 21 is placed on the floor surface of a test site or the like, and a linear motor shaker 3 is provided. It also has a support base 211 above the linear motor shaker 3. A plurality of guide parts 212 for guiding a rod 42, which will be described later, are provided on the support base 211.

[0020] The upper frame 22 is arranged at a predetermined height with respect to the lower frame 21, and the holding means 5 is suspended.

[0021] The lifting cylinder 23 is configured to be able to adjust the height of the upper frame 22 with respect to the lower frame 21 by expanding and contracting. That is, the lifting cylinder 23 may be appropriately expanded and contracted according to the length of the shock absorber 100.

[0022] As shown in FIG. 2, the linear motor shaker 3 includes a case 31, a motor coil 32 fixed to the inner surface of the case 31, an output part 34 that is arranged to be able to move straight inside the motor coil 32 and protrudes outside the case 31, and a magnet 33 fixed to the output part 34. The linear motor shaker 3 is arranged such that the vibration direction is in the Z direction. The output part 34 is formed in a flat plate shape extending along the YZ plane and penetrates the support base 211 in the Z direction.

[0023] The linear motor shaker 3 is provided with a linear encoder 35, which is a displacement sensor for detecting the position of the output part 34. By measuring the time change of the displacement of the output part 34, the speed and acceleration of the output part 34 can be calculated. Due to the connection structure as described later, the output part 34 vibrates integrally with the cylinder part 100A of the shock absorber 100. Therefore, the displacement, speed, and acceleration of the cylinder part 100A can be measured by the linear encoder 35.

[0024] As shown in Figure 3, the relay means 4 includes a support base 41 as the relay unit body and four metal rods 42. The support base 41 is formed as a rectangular plate shape extending along the XY plane, and its upper surface 411 also extends along the XY plane. The rods 42 are guide rods, arranged near the four corners of the support base 41 and extending along the Z direction. That is, two pairs of rods are formed by two rods 42 aligned in the X direction, and two pairs of rods are formed by two rods 42 aligned in the Y direction. Each rod 42 penetrates the support base 211 in the Z direction and is inserted into the guide portion 212. As shown in Figures 4 to 6, the outer circumferential surface 42A of the rod 42 has four planar portions 421 and four connecting surfaces 422. Two of the planar portions 421 extend along the YZ plane, and the other two planar portions 421 extend along the ZX plane. The connecting surface 422 is a curved surface that connects the two planar sections 421, and is arc-shaped when viewed from the Z direction.

[0025] The guide section 212 is a linear bearing having multiple guide rollers 213, and is provided at two locations, above and below the support base 211, for each rod 42. A pair of guide rollers 213 are pivotally supported with the X direction, which is perpendicular to the vibration direction Z, as both the axial direction and width direction, and sandwich the rod 42 from the Y direction. Another pair of guide rollers 213 are pivotally supported with the Y direction, which is perpendicular to the vibration direction Z, as both the axial direction and width direction, and sandwich the rod 42 from the X direction. In other words, the guide rollers 213 are rollers pivotally supported so as to be rotatable around a rotation axis extending in a direction perpendicular to the vibration direction, and do not move in the Z direction, which is the vibration direction, when rotating. The outer circumferential surface of the guide roller 213 has a predetermined width in the axial direction, and its center is convex toward the rod 42 side (it is curved in the cross-section as shown in Figure 4), making it a so-called spherical type roller follower (this convex shape is not shown in Figure 4 because the amount of protrusion is small). As a result, the guide roller 213 makes point-like contact with the flat portion 421 of the rod 42.

[0026] As described above, the flat portion 421 and the guide roller 213 come into contact, and the guide roller 213 is rotatable, so the rod 42 is guided along the Z direction, and consequently the support base 41 also moves along the Z direction.

[0027] The support base 41 is connected to the shock absorber 100 via a connecting jig 200. The jig 200 is shaped to match the shape of the shock absorber 100. In this embodiment, since the shock absorber 100 has a connecting portion 101 on the side of the cylinder portion 100A, the jig 200 is formed in an L-shape, having a portion fixed to the connecting portion 101 and a portion fixed to the upper surface 411 of the support base 41. The upper surface 411 has a plurality of recesses, and the jig 200 can be fixed by placing nuts in these recesses and fastening them with bolts. The tip of the output portion 34 of the linear motor vibrator 3 is fixed to the lower surface of the support base 41. In this way, the relay means 4 transmits vibrations by connecting the output portion 34 of the linear motor vibrator 3 to the connecting portion 101, which is one end of the shock absorber 100.

[0028] The position on the support base 41 to which the output unit 34 of the linear motor exciter 3 is connected is located between two rods 42 aligned in the Y direction on the left side in the X direction in Figure 1, and two rods 42 aligned in the Y direction on the right side in the X direction, and is particularly located in the center. Thus, in the X direction, the output unit 34 of the linear motor exciter 3 is located between each of the two pairs of rods.

[0029] As shown in Figure 7, the holding means 5 includes a displacement mechanism 51, a three-axis load cell 52, a support block 53, and a load control load cell (not shown).

[0030] The displacement mechanism 51 is fixed so as to be suspended from the upper frame 22 and includes a first displacement section 511 that causes displacement in the X direction, a second displacement section 512 that causes displacement in the Y direction, and a fixed block 513 fixed to the upper frame 22. Two rows of groove-shaped rail sections 513A extending along the X direction are formed on the lower surface of the fixed block 513, and the two rows of rail sections 513A are aligned in the Y direction. The first displacement section 511 includes a first movable block 511A provided on the lower side of the fixed block 513, a manual handle 511B for moving the first movable block 511A, and a manual lock lever 511C for fixing the position of the first movable block 511A. The first movable block 511A has a protrusion that projects upward and engages with each of the two rows of rail sections 513A, thereby allowing it to move relative to the fixed block 513 in the X direction. The first displacement section 511 is equipped with a screw feed mechanism, which converts the rotational motion of the manual handle 511B, centered on a rotation axis along the Y direction, into linear motion along the X direction. Specifically, when the tester operates the manual lock lever 511C to unlock and simultaneously operates the manual handle 511B, the first movable block 511A moves in the X direction, and when the manual lock lever 511C is operated to lock it, the first movable block 511A becomes immobile. Furthermore, two rows of groove-shaped rail sections 511D extending along the Y direction are formed on the lower surface of the first movable block 511A, and the two rows of rail sections 511D are aligned in the X direction.

[0031] The second displacement section 512 includes a second movable block 512A provided below the first movable block 511A, a manual handle 512B for moving the second movable block 512A, and a manual lock lever 512C for fixing the position of the second movable block 512A. The second movable block 512A has a protrusion that projects upward and engages with each of the two rows of rail sections 511D, thereby allowing it to move relative to the first movable block 511A in the Y direction. The second displacement section 512 is provided with a screw feed mechanism, so that the rotational motion of the manual handle 512B around a rotation axis along the Y direction is converted into linear motion along the Y direction. When the tester operates the manual lock lever 512C to unlock and operates the manual handle 512B, the second movable block 512A moves in the Y direction, and when the tester operates the manual lock lever 512C to lock it, the second movable block 512A becomes immobile.

[0032] The three-axis load cell 52 is installed below the second movable block 512A and above the support block 53 of the second displacement section 512. That is, it is positioned so as to be sandwiched in the Z direction by the second movable block 512A and the support block 53, and measures the loads in the X, Y, and Z directions that occur between the second movable block 512A and the support block 53. The measurement method of the three-axis load cell 52 is not particularly limited and may be a strain gauge type or a piezoelectric type. The upper measurement limit of the three-axis load cell 52 is, for example, 10 to 30 kN in each direction.

[0033] The support block 53 is formed in a flat plate shape extending along the XY plane and is connected to the shock absorber 100 via a connecting jig 300. Specifically, the lower surface of the support block 53 has a plurality of recesses, and the jig 300 can be fixed by placing nuts in these recesses and fastening them with bolts. The upper part of the jig 300, which is rectangular in shape when viewed from the Y direction, is fixed to the support block 53, and the lower part of the jig 300 is fixed to the upper end 102 of the shaft portion 100B of the shock absorber 100 (the other end of the shock absorber 100). At this time, a load control load cell (not shown) is provided between the support block 53 and the jig 300.

[0034] The load-controlled load cell measures the load in the Z direction, and its upper measurement limit is, for example, several kN (e.g., 1 to 3 kN), which is different from the upper measurement limit of the three-axis load cell 52. The load-controlled load cell, the three-axis load cell 52 as described above, and the three-axis load cell 52 and the load-controlled load cell as described above constitute the load measurement unit, and each of these acts as a measurement unit. When the lateral load applied by the displacement mechanism 51 is relatively small, it is preferable to measure the load in the Z direction using both the three-axis load cell 52 and the load-controlled load cell (or the load-controlled load cell only). When the lateral load is relatively large, it is preferable to remove the load-controlled load cell and measure the load in the Z direction using only the three-axis load cell 52.

[0035] As described above, the connecting portion 101, which is one end of the shock absorber 100, is fixed to the relay means 4 via the jig 200, and the relay means 4 is immovable in the XY plane relative to the lower frame 21. Therefore, the connecting portion 101 is immovable in the XY plane relative to the lower frame 21. Furthermore, the upper end portion 102, which is the other end of the shock absorber 100, is fixed to the holding means 5 via the jig 300, and the holding means 5 is fixed to the upper frame 22. Therefore, when the displacement mechanism 51 is locked, the upper end portion 102 is immovable in the XY plane relative to the upper frame 22. Since the lower frame 21 and the upper frame 22 are immovable relative to each other in the XY plane, the connecting portion 101 and the upper end portion 102 are immovable relative to each other in the XY plane. Therefore, the three-axis load cell 52 measures the load in the XY plane (X direction and Y direction) as a lateral load generated between the connection part 101 and the upper end part 102 of the shock absorber 100, and also measures the load in the Z direction generated between the connection part 101 and the upper end part 102 of the shock absorber 100. The load control load cell measures the load in the Z direction generated between the connection part 101 and the upper end part 102 of the shock absorber 100.

[0036] Furthermore, in the Z direction, only the load due to the vibration of the linear motor vibrator 3 is applied between the connection part 101 and the upper end part 102, and this load is measured by the three-axis load cell 52.

[0037] Furthermore, the X and Y direction measurements obtained by the 3-axis load cell 52 are displayed on a display unit, such as a screen, so that the tester can see them. That is, the tester can adjust the displacement in the X and Y directions by operating the manual handles 511B and 512B based on the displayed measurements. In the case of test conditions where no lateral load is applied, the displacement mechanism 51 sets its origin to a position where no load is applied to the shock absorber 100 (displacement amounts in the X and Y directions are 0). However, errors may occur due to manufacturing errors or repeated measurements, and even if the displacement mechanism 51 is positioned at the origin, some load may be measured in the XY plane. Even in the test conditions where no lateral load is applied, the displacement mechanism 51 is used to adjust the displacement in the X and Y directions so that the lateral load is 0.

[0038] As shown in Figures 5 and 6, the braking means 6 includes a pair of clamping units 61A and 61B provided on both sides of the rod 42 in a direction along the XY plane (the X direction in the example shown in Figures 5 and 6), and a sensor 62. The braking means stops the movement of the rod 42 in the Z direction by holding the connecting surface 422 of the outer circumferential surface 42A of the rod 42, which is the object to be braked. Each of the clamping units 61A and 61B includes a clamping portion 63 for contacting and clamping the rod 42, a shaft portion 64 connected to the clamping portion 63 and extending away from the rod 42, a compression spring 65 as a biasing means for applying a biasing force to the clamping portion 63, and a hydraulic drive unit 66 for applying a force to the shaft portion 64 in the opposite direction to that of the compression spring 65.

[0039] The pair of clamping portions 63 are metal parts that clamp the rod 42 by approaching each other in the X direction. On the side facing the rod 42, the clamping portions 63 are formed in a concave shape with a pair of tapered surfaces 631 inclined in the X direction and a bottom surface 632 formed between the pair of tapered surfaces 631. The tapered surfaces 631 abut against the connection surface 422 of the rod 42. At this time, the connection surface 422 is curved, while the tapered surfaces 631 are flat. These may also be in linear contact in a straight line extending in the Z direction. Alternatively, the outer circumferential surface 42A of the rod 42 and the clamping portions 63 may be made of metals with different hardnesses, and the softer metal may deform slightly to achieve a predetermined contact width. Furthermore, as shown in Figure 5, when the connection surface 422 and the tapered surfaces 631 come into contact, the flat portion 421 of the rod 42 is separated from the bottom surface 632, so that no braking force is applied to the flat portion 421.

[0040] The shaft portion 64 is inserted through the compression spring 65. The clamping portion 63 connected to one end of the shaft portion 64 has a larger diameter than the shaft portion 64, and the case 661 of the hydraulic drive unit 66 connected to the other end of the shaft portion 64 has a larger diameter than the shaft portion 64. As a result, the compression spring 65 is positioned between the clamping portion 63 and the hydraulic drive unit 66 and is compressible.

[0041] The end of the shaft portion 64 opposite to the clamping portion 63 is a flange portion 641, which divides the space inside the case 661 in the X direction. By introducing hydraulic fluid into the two divided spaces inside the case 661, a hydraulic driving force is applied to the flange portion 641 according to the pressure difference between these spaces.

[0042] Sensor 62 is a proximity sensor that detects changes in induced current caused by the approach of a metal member. It is attached to one of a pair of clamping parts 63 and detects the approach of a metal member 67 attached to the other clamping part 63 (it detects whether the metal member 67 is located within a predetermined range). In other words, sensor 62 detects the distance between the pair of clamping parts 63. Brake means 6 is connected to the control unit of the test device 1 in a way that allows communication (either wired or wireless communication), and when the distance between sensor 62 and the metal member 67 exceeds a predetermined value, it transmits a release completion signal to the control unit. In other words, the release completion signal is a signal indicating that the distance between the pair of clamping parts 63 has exceeded a predetermined value.

[0043] This braking means 6 holds the rod 42 and stops its movement when the hydraulic drive unit 66 is not operating (when the pressure on both sides of the flange portion 641 is approximately equal). That is, when the clamping portion 63 is in contact with the rod 42, the compression spring 65 is compressed by a predetermined amount from its natural state (undeformed state), generating a biasing force in the direction of holding the rod 42 (moving towards the rod 42). In this state, when hydraulic fluid is introduced into the space on the rod 42 side of the flange portion 641 within the case 661 to increase the pressure, a driving force opposite to the biasing force of the compression spring 65 is generated, compressing the compression spring 65 and causing the shaft portion 64 and clamping portion 63 to move away from the rod 42, thus releasing the brake. That is, the hydraulic drive unit 66 functions as a means of generating a release force that generates a release force against the biasing force of the compression spring 65. When the pair of clamping portions 63 have separated sufficiently, a release completion signal is transmitted from the sensor 62 to the control unit.

[0044] By reducing the pressure in the space on the rod 42 side of the flange portion 641 within the case 661, the biasing force of the compression spring 65 causes the shaft portion 64 and the clamping portion 63 to move closer to the rod 42, and the movement of the rod 42 is stopped again.

[0045] Here, an example of the procedure for testing the shock absorber 100 in the test apparatus 1 will be described. First, the tester positions the displacement mechanism 51 at the origin and connects the shock absorber 100 to the support base 41 via the jig 200 and to the support block 53 via the jig 300. Next, the tester unlocks the manual lock levers 511C and 512C and adjusts the displacement in the X and Y directions by operating the manual handles 511B and 512B. At this time, the displacement in the X and Y directions may be adjusted alternately, or the displacement in one direction may be determined first and then the displacement in the other direction may be determined. Once the adjustment of the displacement is complete, the operator locks the manual lock levers 511C and 512C.

[0046] When adjusting the displacement of the displacement mechanism 51 in this way, the tester should perform the work while confirming the measured value, which is measured by the three-axis load cell 52 and displayed as described above.

[0047] Next, when the tester initiates the test start operation on the computer or other device used to operate the test apparatus 1, the control unit sends a release command signal to the brake means 6 to release the brake, and also sends a signal to the linear motor vibrator 3 to supply power to maintain its position. Upon receiving the release command signal, the brake means 6 introduces hydraulic fluid into the space within the case 661 on the rod 42 side of the flange portion 641, and when the distance between the sensor 62 and the metal member 67 exceeds a predetermined value, it sends a release completion signal to the control unit. Upon receiving the release completion signal, the control unit sends a vibration start signal to the linear motor vibrator 3 to start the vibration.

[0048] While the linear motor vibrator 3 is applying vibration to the shock absorber 100, the control unit monitors information about the vibration applied by the linear motor vibrator 3 (amplitude, frequency, phase, etc.) and receives information measured from the linear encoder 35 (time change in displacement). The control unit may output the monitored and measured information directly to the external device, or it may process it appropriately before outputting it to the external device.

[0049] At the end of the test, the tester performs a test termination operation on the computer or other device used to operate the test apparatus 1. This causes the control unit to transmit a vibration stop signal to the linear motor vibrator 3. Upon receiving the vibration stop signal, the linear motor vibrator 3 stops vibrating and maintains power supply to maintain this stopped position. After a predetermined time has elapsed since transmitting the vibration stop signal, or after determining that the linear motor vibrator 3 has stopped based on, for example, the measurement information from the linear encoder 35, the control unit transmits a hold command signal to the brake means 6. Upon receiving the hold command signal, the brake means 6 reduces the pressure in the space on the rod 42 side of the flange portion 641 within the case 661, and when the distance between the sensor 62 and the metal member 67 falls below a predetermined value, it transmits a hold completion signal to the control unit. Upon receiving the hold completion signal, the control unit transmits a power supply termination signal to the linear motor vibrator 3 and terminates the power supply for maintaining the stopped position.

[0050] Furthermore, if the time difference between the timing when the linear motor vibrator 3 starts or stops vibrating and the timing when the brake means 6 holds or releases the rod 42, and the distance the output unit 34 descends due to gravity during this time is short, then it is not necessary to supply power to maintain the position.

[0051] As described above, if the control unit does not receive a release completion signal after sending a release command signal to the brake means 6, a vibration start signal will not be sent to the linear motor vibrator 3, and therefore vibration will not start.

[0052] According to this embodiment, the braking means 6 stops the movement of the rod 42 of the relay means 4 that transmits vibration from the linear motor vibrator 3 to the shock absorber 100. This allows the position at the end of vibration to be maintained even when the power supply to the linear motor vibrator 3 is terminated, and reduces the power consumption required to maintain the position at the end of vibration.

[0053] Furthermore, since the braking means 6 holds the outer circumferential surface 42A of the rod 42 of the relay means 4, there is no need to form a held part on the linear motor vibrator 3, making it easier to standardize the linear motor vibrator 3 among test devices with different specifications. In addition, the rod 42 is easier to configure to have high rigidity compared to the output section 34 of the linear motor vibrator 3. As a result, a large holding force (clamping force) can be applied to the rod 42, improving the reliability of position holding by the braking means 6.

[0054] Furthermore, by having the braking means 6 hold two diagonally opposite rods 42 of the four rods 42 arranged in a square shape in the relay means 4, it is possible to suppress tilting of the support base 41 when the position at the end of vibration is maintained by the braking means 6.

[0055] Furthermore, by having the braking means 6 hold a connection surface 422 on the outer circumferential surface 42A of the rod 42 that is different from the flat surface 421, the region on the outer circumferential surface 42A of the rod 42 can be made independent of the region that is subject to braking and the region that is guided during vibration in the Z direction. As a result, even if changes such as scratches or deformation occur on the outer circumferential surface 42A of the rod 42 due to repeated braking, it is less likely to affect the guidance of the rod 42 by the guide portion 212, and the rod 42 can be guided smoothly.

[0056] Furthermore, the braking means 6 has a compression spring 65 that generates a biasing force in the direction toward the rod 42 that is to be braked, and the hydraulic drive unit 66 generates a release force against the biasing force of the compression spring 65. This ensures that even if a malfunction occurs in the hydraulic drive unit 66 and no release force is generated, the compression spring 65 can maintain the cessation of movement in the Z direction. Additionally, by driving the linear motor exciter 3 when the control means receives a release completion signal, the linear motor exciter 3 can be prevented from being driven if the brake is not released due to some malfunction.

[0057] Furthermore, by starting the vibration of the linear motor vibrator 3 when the distance between the sensor 62 and the metal member 67 exceeds a predetermined value, it is possible to prevent the linear motor vibrator 3 from being driven while the clamping of the rod 42 by the pair of clamping parts 63 is not released. In addition, if a malfunction occurs in the sensor 62 or if there is a problem with communication between the sensor 62 and the control unit, the linear motor vibrator 3 will not be driven.

[0058] Furthermore, since the holding means 5 includes not only the displacement mechanism 51 but also a three-axis load meter 52 and a load control load cell, it is possible to measure the load applied to the shock absorber 100 in the XY plane while simultaneously measuring the load in the Z direction (i.e., the characteristics of the shock absorber 100). In other words, the upper end portion 102 of the shock absorber 100 can be positioned in the XY plane so that a desired load is applied to the shock absorber 100, thereby improving the reproducibility of actual driving conditions.

[0059] Furthermore, since the guide roller 213 is pivotally supported so as to be rotatable around a rotation axis extending in a direction perpendicular to the vibration direction Z, and is immovable in the Z direction, contact between such a guide roller 213 and the flat portion 421 of the rod 42 can suppress displacement such as rotation (twisting) of the shock absorber 100 around an axis along the extension and contraction direction. Moreover, by combining a guide roller 213 with its axial direction in the X direction and a guide roller 213 with its axial direction in the Y direction, such displacement can be further suppressed.

[0060] Furthermore, by positioning the output section 34 between two pairs of rods 42 in the X direction, when the upper end 102 of the shock absorber 100 is displaced by the displacement mechanism 51, the displacement of the lower end connection section 101 in the X direction is suppressed, allowing for stable vibration application. In addition, since the four rods 42 form two pairs of rods 42 aligned in the Y direction, and the output section 34 extends along the Y direction, the displacement of the connection section 101 in the Y direction can also be suppressed.

[0061] Furthermore, because the direction in which the rods 42 are aligned coincides with the direction of displacement caused by the displacement mechanism 51, the displacement of the connection part 101 is easily suppressed, and vibration can be applied more stably.

[0062] Furthermore, since the holding means 5 has a triaxial load cell 52 and a load control load cell as two measuring units with different upper measurement limits, it is possible to select the measuring unit to use according to the load applied in a direction intersecting the expansion and contraction direction, thereby improving the degree of freedom in setting the load in a direction intersecting the expansion and contraction direction and improving the measurement accuracy.

[0063] It should be noted that the present invention is not limited to the embodiments described above, and includes other configurations that can achieve the objectives of the present invention, and modifications such as those shown below are also included in the present invention. For example, in the above embodiment, the brake means 6 holds two diagonally opposite rods 42 of the four rods 42 arranged in a square shape in the relay means 4, but the rods 42 to be held are not limited to this, and any combination of two or three rods 42 may be held, all of the rods 42 may be held, or only one rod 42 may be held. Furthermore, the number and arrangement of the rods should be set appropriately so as to stably transmit vibrations to the test specimen.

[0064] Furthermore, in the above embodiment, the braking means 6 holds a connection surface 422 of the outer circumferential surface of the rod 42 that is different from the flat portion 421. However, for example, the braking means may hold the outer circumferential surface of a cylindrical or cylindrical rod, and the held area and the guided area may be common. With such a configuration, the shape of the rod can be simplified. Also, the mechanism for guiding the rod of the relay means is not limited to one using rollers, but may also use balls such as ball splines.

[0065] Furthermore, the braking means is not limited to holding the outer surface of the rod; it may also hold other parts of the relay means 4, or it may directly hold the output section 34 of the linear motor vibrator 3, or a braking means that holds both of these may be provided.

[0066] Furthermore, the method of stopping movement by a braking mechanism is not limited to holding using a force in a direction intersecting the vibration direction, such as clamping or gripping, but may also be movement restriction by contact between two members in the direction of vibration, such as locking.

[0067] Furthermore, in the above embodiment, the linear motor vibrator 3 is started to vibrate when the distance between the sensor 62 and the metal member 67 exceeds a predetermined value. However, the method for detecting holding by the brake means and its release is not limited to measuring distance, and may be detected by, for example, a physical switch. Also, the control unit may transmit a signal for brake release and a signal for vibration start approximately simultaneously. In this case, for example, a detection unit capable of detecting malfunctions in the vibration excitation means may be provided, and the control may be configured to emergency activate the brake means when a malfunction is detected.

[0068] Furthermore, in the above embodiment, the brake means 6 has a compression spring 65 that generates a biasing force in the direction of holding the rod 42, and the hydraulic drive unit 66 generates a release force against the biasing force of the compression spring 65. However, the brake means may also have a biasing means that generates a biasing force in the direction of releasing the holding, and a drive unit that generates a force in the holding direction, or it may not have a biasing means and may have a drive unit that can be driven in both the holding direction and the releasing direction.

[0069] Furthermore, although the linear motor vibrator 3 was exemplified as an electrically powered vibration exciter in the above embodiment, the electrically powered vibration exciter may be, for example, an electrodynamic type, and the specific method is not particularly limited as long as it generates vibration by supplying power (i.e., utilizes the magnetic force generated by electric current).

[0070] Although embodiments of the present invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments, and any design changes, etc., that do not depart from the spirit of the present invention are also included. [Explanation of Symbols]

[0071] 1…Test device, 3…Linear motor vibrator (vibration means), 34…Output unit, 4…Relay means, 41…Support base (relay main body), 42…Rod, 421…Planar part, 422…Connecting surface, 6…Brake means, 62…Sensor, 63…Clamping part, 65…Compression spring (biasing means), 66…Hydraulic drive unit (release force generating means), 100…Shock absorber (test specimen), 101…Connecting part (one end)

Claims

1. A test apparatus for measuring the characteristics of a test specimen by applying vibration in a direction along the vertical direction, An electrically powered vibration excitation method that generates vibrations when electricity is supplied, A relay means connected to the output section of the excitation means and one end of the test specimen in the direction of vibration to transmit vibrations, A test apparatus characterized by comprising a braking means for stopping movement in the vibration direction of at least one of the output unit and the relay means, which is the target of braking.

2. The relay means comprises a relay body portion extending along a plane intersecting the vibration direction, and a plurality of rods connected to the relay body portion and extending along the vibration direction and guided along the vibration direction. The test apparatus according to claim 1, characterized in that the braking means holds the outer circumferential surface of the rod.

3. The aforementioned plurality of rods include four rods arranged in a square shape, The test apparatus according to claim 2, characterized in that the braking means holds each of the two rods among the four rods that are arranged on the diagonals of the rectangle.

4. The outer surface of the rod has a plurality of planar portions extending along a plane including the vibration direction, and a connecting surface connecting two of the planar portions. The test apparatus according to claim 2 or 3, characterized in that the braking means holds the connecting surface.

5. The system further comprises control means for controlling the vibration excitation means, The braking means comprises a biasing means that generates a biasing force in the direction toward the object to be braked, and a release force generating means that generates a release force opposite to the biasing force. The test apparatus according to any one of claims 1 to 3, characterized in that the control means drives the excitation means when it receives a release completion signal from the brake means indicating that the holding has been released.

6. The braking means includes a pair of clamping parts that clamp the object to be braked by approaching each other, and a sensor that detects the distance between the pair of clamping parts. The test apparatus according to claim 5, characterized in that the control means receives a signal from the sensor indicating that the distance between the pair of clamping portions has exceeded a predetermined value as the release completion signal.

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