Vibration test device

Abstract

The purpose of the present invention is to improve the linear accuracy of an oscillating unit.　A vibration test device (1) according to one embodiment of the present invention comprises: a base (2); a vibrating table (3) to which a specimen is attached; and at least one oscillating unit (5, 6) that oscillates the vibrating table in a predetermined oscillating direction. The oscillating unit is provided with a linear actuator (10) installed on the base and capable of outputting reciprocating linear motion in the oscillating direction, and linear guide parts (50X, 50Y) installed on the base and capable of transmitting the reciprocating linear motion output from the linear actuator to the vibrating table. The linear guide part is provided with fixed frames (51X, 51Y) fixed on the base, a movable frame (53) driven by the linear actuator, and a slider (52S) for limiting the movable direction of the movable frame to the oscillating direction. The slider is provided with a plurality of carriages arranged in the oscillating direction.

Description

Vibration test device

[0001] The present invention relates to a vibration test device.

[0002] In an electrodynamic actuator used for a vibration test, in order to improve the linear accuracy of a movable part, a movable part support mechanism that supports the movable part slidably from the side is provided in International Publication No. 2017 / 122770 (Patent Document 1).

[0003] The electrodynamic actuator 100A described in Patent Document 1 (for example, FIGS. 1, 20, etc.) includes four movable part support mechanisms 140 arranged at equal intervals around the movable part 120. The movable part support mechanism 140 includes an angle plate attached to the fixed part 110 of the electrodynamic actuator 100A and a linear guide that slidably connects the angle plate and the movable part 120 in the vibration direction (X-axis direction).

[0004] In the electrodynamic actuator 100A described in Patent Document 1, most of the movable part 120 is housed in the hollow part of the fixed part 110, and only the tip part of the movable part 120 exposed outside the fixed part 110 is supported by the movable part support mechanism 140. Therefore, in the movable part support mechanism 140, a sufficient support length cannot be ensured in the vibration direction, and a desired linear accuracy may not be obtained.

[0005] The present invention has been made in view of the above circumstances, and an object thereof is to improve the linear accuracy of a vibration unit.

[0006] According to one embodiment of the present invention, a vibration testing apparatus is provided comprising a base, a vibrating table on which a test specimen is attached, and an excitation unit for excitation of the vibrating table in a predetermined excitation direction, wherein the excitation unit comprises a linear actuator mounted on the base that is capable of outputting reciprocating linear motion in the excitation direction, and a linear guide mounted on the base that transmits the reciprocating linear motion output from the linear actuator to the vibrating table, wherein the linear guide comprises a movable frame driven by the linear actuator and a slider that restricts the direction of movement of the movable frame to the excitation direction, the slider comprises one or more linear guides, the linear guide comprises a rail extending in the excitation direction and one or more carriages that can travel on the rail, and the slider includes a plurality of carriages arranged in the excitation direction.

[0007] According to one embodiment of the present invention, the linear accuracy of the vibration unit can be improved.

[0008] This is a perspective view of a vibration testing apparatus according to one embodiment of the present invention. This is a plan view of a vibration testing apparatus according to one embodiment of the present invention. This is a front view of a vibration testing apparatus according to one embodiment of the present invention. This is a left side view of a vibration testing apparatus according to one embodiment of the present invention. This is a left side view of a Y vibration unit. This is a perspective view of the linear guide section of a Y vibration unit. This is a perspective view of the upper part of the linear guide section. This is a perspective view of the linear guide section of an X vibration unit. This is a perspective view of a Z vibration unit. This is a perspective view of the slide coupling mechanism of a Z vibration unit. This is a block diagram showing the schematic configuration of a control system. This is a perspective view of the slide coupling mechanism and movable part support mechanism of a first modified example. This is a perspective view of the slide coupling mechanism and movable part support mechanism of a second modified example. This is a left side view (partial cross-sectional view) of the movable part support mechanism and slide coupling mechanism of a third modified example.

[0009] Embodiments of the present invention will be described below with reference to the drawings. In the following description, the same or corresponding items will be denoted by the same or corresponding reference numerals, and redundant explanations will be omitted. Furthermore, in each drawing, if multiple items with the same reference numerals are shown, not all of those multiple items will necessarily be denoted by reference numerals, and the assignment of reference numerals will be appropriately omitted for some of those multiple items.

[0010] Figures 1 to 4 are external views (perspective view, plan view, front view, and left side view, respectively) of a vibration testing apparatus 1 according to one embodiment of the present invention. In the following description, the direction from the upper right to the lower left in Figure 1 is defined as the X direction, the direction from the upper left to the lower right is defined as the Y direction, and the direction from the bottom to the top is defined as the Z direction. The X and Y directions are mutually orthogonal horizontal directions, and the Z direction is the vertical direction. Hereinafter, "X-axis," "Y-axis," and "Z-axis" will be abbreviated as "X," "Y," and "Z."

[0011] The vibration testing apparatus 1 is a three-axis simultaneous vibration testing apparatus capable of simultaneously and independently exciting a vibration table 3 on which a test specimen is mounted in three orthogonal directions (X, Y, and Z directions). The vibration testing apparatus 1 comprises a base 2, a vibration table 3, and an X-excitation unit 5, a Y-excitation unit 6, and a Z-excitation unit 7, which are capable of exciting the vibration table 3 in the X, Y, and Z directions, respectively. The X-excitation unit 5, the Y-excitation unit 6, and the Z-excitation unit 7 are each installed on the base 2.

[0012] Figure 5 is a left side view of the Y-vibration unit 6. The Y-vibration unit 6 comprises an electrodynamic actuator 10Y (voice coil motor), a pair of fixed support mechanisms 20, a linear guide section 50Y, and a sliding coupling mechanism 60.

[0013] In this embodiment, the X-vibration unit 5, Y-vibration unit 6, and Z-vibration unit 7 are each equipped with a common electrodynamic actuator 10 (10X, 10Y, and 10Z) as a vibration generating device. The electrodynamic actuator 10 is a linear actuator capable of outputting reciprocating linear motion in a predetermined excitation direction.

[0014] Alternatively, a different type of linear actuator may be used as the vibration generator instead of the electrodynamic actuator 10. Examples of other types of linear actuators include a linear actuator combining a rotary motor with a motion conversion mechanism that converts rotational motion into linear motion (e.g., a lead screw mechanism such as a ball screw or a crank mechanism), a linear motor, a hydraulic cylinder, etc. Furthermore, different types of vibration generators may be used for the X vibration unit 5, the Y vibration unit 6, and the Z vibration unit 7.

[0015] The electrodynamic actuator 10 comprises a substantially cylindrical fixed part 11 attached to the base 2 via a pair of fixed part support mechanisms 20, and a substantially cylindrical movable part 12 housed in the hollow part of the fixed part 11, except for its tip. The movable part 12 is driven axially (in the vibration direction) relative to the fixed part 11.

[0016] The fixed support mechanism 20 includes a fixed part 21 attached to the base 2, a floating part 22 attached to the fixed part 11 of the electrodynamic actuator 10, and at least one linear guide 23 and a buffer part 24 interposed between the fixed part 21 and the floating part 22. The fixed part 21 includes a main body 211 fixed to the base 2, and at least one arm 212 fixed to, for example, the back (left side in Figure 5) or front (right side in Figure 5) of the main body 211 and extending upward. The main body 211 and the arm 212 may be formed integrally. In addition, one or more arms 212 may be provided on both the back and front sides of the main body 211.

[0017] The linear guide 23 is, for example, a ball circulating linear bearing or a roller circulating linear bearing (preferably a guideway type circulating linear bearing or a linear guideway), and comprises a rail 23a extending in the vibration direction and one or more carriages 23b that can travel on the rail 23a. One of the rail 23a and the carriage 23b (for example, the rail 23a) is attached to the upper surface of the fixed part 21, for example, the main body 211, and the other (for example, the carriage 23b) is attached to the lower surface of the floating part 22.

[0018] The linear guide 23 supports the floating section 22 and the electrodynamic actuator 10 in the vertical direction. Furthermore, the linear guide 23 restricts the movement direction of the floating section 22 (and the fixed section 11 of the electrodynamic actuator 10 to which the floating section 22 is fixed) to only the excitation direction of the electrodynamic actuator 10. In addition, the linear guide 23 enables smooth, low-friction movement of the floating section 22 in the excitation direction.

[0019] The buffer portion 24 is sandwiched, for example, between the back or front of the floating portion 22 and the arm 212. One or more buffer portions 24 may be sandwiched between one arm 212 and the floating portion 22, or one or more buffer portions 24 may be sandwiched between multiple arms 212 and the floating portion 22.

[0020] The buffer section 24 has elasticity and viscosity as a whole, and reduces the transmission of vibrations from the floating section 22 to the fixed section 21, especially in the high frequency range, and also dampens the vibrations of the floating section 22. The buffer section 24 is composed of elastic elements (e.g., coil springs, spiral springs, leaf springs, disc springs, air springs, etc.) and viscous elements (e.g., oil dampers, gel-like resin members such as silicone gel), or viscoelastic elements (e.g., rubber members or resin members) connected in parallel or in series. The buffer section 24 may also be provided with a neutral return mechanism to automatically return the floating section 22 to the reference position (neutral position). As a neutral return mechanism, for example, two spring members connected in parallel that provide a restoring force in opposite directions can be used.

[0021] The fixed part support mechanism 20 has the function of suppressing the transmission of vibrations in the excitation direction of the fixed part 11 of the electrodynamic actuator 10 to the base 2, and also suppressing the transmission of vibrations in the excitation direction from the base 2 to the fixed part 11. As a result, the transmission of vibrations between each excitation unit 5, 6, and 7 via the base 2 is suppressed, and vibration noise is reduced.

[0022] Figure 6 is a perspective view of the linear guide section 50Y to which the slide coupling mechanism 60 is attached. The linear guide section 50Y transmits the reciprocating linear motion in the excitation direction (i.e., vibration in the Y direction) output from the electrodynamic actuator 10Y of the Y excitation unit 6 to the vibration table 3 via the slide coupling mechanism 60. The linear guide section 50Y also more precisely restricts the direction of movement of the movable part 6m of the Y excitation unit 6 to the Y direction (i.e., the excitation direction), improving the excitation accuracy of the Y excitation unit 6. This reduces vibration noise in the X and Z directions (i.e., non-excitation directions) of the movable part 6m. The movable part 6m of the Y excitation unit 6 includes the movable part 12 of the electrodynamic actuator 10 and the movable frame 53 of the linear guide section 50Y, which will be described later.

[0023] The linear guide section 50Y comprises a fixed frame 51Y, a slider 52S, and a movable frame 53. The slider 52S is composed of a set, i.e., one or more (preferably multiple) linear guides 52.

[0024] The fixed frame 51Y is a base that supports the linear guide 52, and has a body portion 51Yb extending in the X direction, which is a horizontal direction perpendicular to the excitation direction, a pair of legs 51Yc extending downward from both ends of the body portion 51Yb in the X direction, and an arm portion 51Ya extending diagonally upward from the center of the body portion 51Yb in the X direction toward the vibrating table 3. The fixed frame 51Y is fixed to the base 2 at the bottom surfaces of the pair of legs 51Yc. A horizontal mounting surface 51Ym is formed on the upper surface of the arm portion 51Ya to which the linear guide 52 is attached.

[0025] In the Y-vibration unit 6, as shown in Figure 1, the Z-vibration unit 7's fixed support mechanism 30, described later, is positioned between the Z-vibration unit 7's electrodynamic actuator 10, which supports the vibrating table 3 from below, and the Z-vibration unit 7's leg portion 51Yc. Therefore, the leg portion 51Yc and the body portion 51Yb of the fixed frame 51Y cannot be installed close to the Z-vibration unit 7's electrodynamic actuator 10 or the vibrating table 3. In this embodiment, the fixed frame 51Y is equipped with an arm portion 51Ya extending diagonally upward in the Y direction, making it possible to support the movable portion 6m (more directly, the movable frame 53) of the Y-vibration unit 6 with high rigidity at a position closer to the vibrating table 3. This configuration improves the vibration accuracy of the Y-vibration unit 6.

[0026] As shown in Figure 6, the movable frame 53 has, for example, a roughly rectangular main plate 53a arranged horizontally, an octagonal mounting plate 53b fixed vertically to the rear end of the main plate 53a, and three triangular plate-shaped ribs 53c connecting the upper surface of the main plate 53a and the mounting plate 53b. The movable frame 53 only needs to have sufficient rigidity, lightness, symmetry (i.e., weight balance), and mounting area necessary for attaching the slider 52S, and its shape is not limited to that of this embodiment.

[0027] Figure 7 is a perspective view from below of the upper part 50U (including the movable frame 53 and linear guide 52) of the linear guide section 50Y to which the slide coupling mechanism 60 is attached.

[0028] The movable frame 53 has three ribs 53e, 53d, and 53e that protrude from the lower surface of the main plate 53a and extend in the Y direction. The ribs 53e, 53d, and 53e are connected to the main plate 53a and the mounting plate 53b, respectively, reinforcing the main plate 53a and the mounting plate 53b, and also reinforcing the connection between the main plate 53a and the mounting plate 53b.

[0029] The specific details of the number, shape, and arrangement of the ribs 53c to e of the movable frame 53 are not limited to those of this embodiment. For example, ribs 53e, 53d, and 53e may be provided on the upper surface of the main plate 53a instead of (or in addition to) rib 53c, or rib 53c may be provided on the lower surface of the main plate 53a instead of (or in addition to) ribs 53e, 53d, and 53e. Also, if the main plate 53a (or mounting plate 53b) has sufficient rigidity, ribs 53d, 53e (or rib 53c) may not be provided. Furthermore, an additional rib extending in the X direction may be provided, connecting ribs 53e, 53d, and 53e at the center in the Y direction. In this case, one of the two linear guides 52 aligned in the Y direction can be placed in front of the additional rib (on the vibrating table 3 side), and the other can be placed behind the additional rib (on the electrodynamic actuator 10 side).

[0030] The front end of the main plate 53a (the end on the vibrating table 3 side in the Y direction) is provided with a pair of widening portions 53f protruding from both sides, and the width of the main plate 53a (size in the X direction perpendicular to the excitation direction) gradually increases as it approaches the front end. The width of the movable frame 53 is expanded at the front end to be approximately the same size as the length of the rail 61a of the slide coupling mechanism 60 (or the width of the vibrating table 3), which will be described later. The front surface of the movable frame 53 in the excitation direction is a plane perpendicular to the excitation direction and becomes the mounting surface 53g to which the slide coupling mechanism 60 is attached.

[0031] The linear guide section 50Y includes a slider 52S consisting of one or more (for example, four) linear guides 52. The linear guides 52 support the movable frame 53 so that it can move relative to the fixed frame 51Y only in the excitation direction of the Y excitation unit 6. The linear guides 52 are, like the linear guides 23 of the fixed support mechanism 20, for example, guideway-type circulating linear bearings. Each linear guide 52 includes one rail 52a extending in the Y direction and one carriage 52b that can travel on the rail 52a.

[0032] In this embodiment, four linear guides 52 are arranged in pairs in two rows (in other words, in a grid pattern in two horizontal directions, the X and Y directions). A pair of linear guides 52 aligned in the Y direction are housed in a recess between a rib 53d and one rib 53e, and another pair of linear guides 52 aligned in the Y direction are housed in a recess between a rib 53d and the other rib 53e. One of the rails 52a and carriages 52b of the linear guides 52 (for example, the rail 52a) is attached to the movable frame 53, and the other is attached to the fixed frame 51Y.

[0033] The linear guide 52 may be equipped with multiple carriages 52b. In this embodiment, each linear guide 52 is equipped with a rail 52a of the same length and the same number of carriages 52b, but the length of the rail 52a and the number of carriages 52b may differ from those in this embodiment. For example, the linear guide section 50Y may be equipped with a pair of linear guides 52' arranged in the X direction, each equipped with one long rail 52a' (for example, about twice the length of the rail 52a in this embodiment) and multiple carriages 52b (for example, two). Also, the linear guides 52 may be arranged in three or more rows in the X direction. Also, the carriages 52b may be arranged in three or more rows in the Y direction.

[0034] The sliding connection mechanism 60 is a mechanism that connects the vibrating table 3 and the movable frame 53 of the linear guide section 50Y so that they can slide in two directions perpendicular to the excitation direction of the Y excitation unit 6 (i.e., the X direction and the Z direction).

[0035] As shown in Figure 6, the sliding coupling mechanism 60 includes one or more first linear guides 61 that slidably connect the movable frame 53 of the linear guide section 50Y and the vibrating table 3 in a horizontal direction perpendicular to the excitation direction of the Y excitation unit 6 (i.e., the X direction), and one or more second linear guides 62 that slidably connect them in a vertical direction (Z direction). Both the first linear guides 61 and the second linear guides 62 are, like the linear guides 23 of the fixed support mechanism 20, for example, guideway-type circulating linear bearings.

[0036] The first linear guide 61 comprises a single rail 61a extending in the X direction and a plurality (for example, three) of carriages 61b that can travel on the rail 61a. The sliding coupling mechanism 60 comprises the same number of second linear guides 62 as carriages 61b. The rail 61a of the first linear guide 61 is attached to the mounting surface 53g of the movable frame 53 of the linear guide section 50Y, and the rails 62a of the plurality of second linear guides 62 are attached, for example, at equal intervals to the side of the vibrating table 3 facing the Y excitation unit 6.

[0037] The carriage 61b of the first linear guide 61 and the carriage 62b of the second linear guide 62 are formed with mounting holes for directly fixing them to each other, for example, by bolts. This allows the carriages 61b and 62b to be directly fixed to each other (i.e., without the use of mounting plates or the like). This configuration reduces the weight (and inertia) of the slide coupling mechanism 60 and improves the vibration performance of the Y vibration unit 6.

[0038] The carriage 61b of the first linear guide 61 and the carriage 62b of the second linear guide 62 may be identically constructed. This configuration allows for the common use of components, thereby reducing the costs required for procuring and managing those components.

[0039] The X-vibration unit 5 differs from the Y-vibration unit 6 in that it has a linear guide section 50X instead of a linear guide section 50Y, but its other configurations are the same as the Y-vibration unit 6. In the X-vibration unit 5, the X direction is the vibration direction.

[0040] Figure 8 is a perspective view of the linear guide section 50X to which the slide coupling mechanism 60 is attached. The linear guide section 50X differs from the linear guide section 50Y in that it has a fixed frame 51X instead of the fixed frame 51Y, but the other configurations are the same as those of the linear guide section 50Y.

[0041] The fixed frame 51X has a body portion 51Xb that extends in the Y direction, which is a horizontal direction perpendicular to the vibration direction, and a pair of legs 51Xc that extend downward from both ends of the body portion 51Xb in the Y direction. However, it does not have a portion corresponding to the arm portion 51Ya of the fixed frame 51Y, and the linear guide 52 is attached to the upper surface of the body portion 51Xb. In addition, the legs 51Xc are longer by the height of the arm portion 51Ya that the fixed frame 51X does not have, and the upper surface of the body portion 51Xb to which the linear guide 52 is attached is at the same height as the upper surface of the arm portion 51Ya of the fixed frame 51Y.

[0042] In the X vibration unit 5, as shown in Figure 1, the Z vibration unit 7's fixed part support mechanism 30 is not interposed between the Z vibration unit 7's electrodynamic actuator 10 and the fixed frame 51Xc. Therefore, the fixed frame 51X can be installed close to the Z vibration unit 7's electrodynamic actuator 10 and the vibration table 3. As a result, the fixed frame 51X in this embodiment can support the movable part 5m (more specifically, the movable frame 53) of the X vibration unit 5 with high rigidity at a position close to the vibration table 3, even without providing an arm portion 51Ya.

[0043] Figure 9 is a perspective view of the Z-vibration unit 7. The Z-vibration unit 7 comprises an electrodynamic actuator 10, a pair of fixed support mechanisms 30, a movable support mechanism 40, and a slide coupling mechanism 70 (Figure 10). Note that the slide coupling mechanism 70 is omitted from the illustration in Figure 9.

[0044] The electrodynamic actuator 10 is positioned with its excitation direction oriented in the Z direction and is supported by a pair of fixed part support mechanisms 30 attached to both sides of the fixed part 11 in the Y direction. Alternatively, the pair of fixed part support mechanisms 30 may be attached to both sides of the fixed part 11 in the X direction. Furthermore, two pairs of fixed part support mechanisms 30 may be attached to both sides of the fixed part 11 in the X and Y directions.

[0045] The fixed part support mechanism 30 includes a pair of fixed parts 31 attached to the base 2, a floating part 32 attached to the fixed part 11 of the electro-dynamic actuator 10, a pair of linear guides 33 interposed between each fixed part 31 and the floating part 32, and a pair of buffer parts 34 interposed between the base 2 and the floating part 32.

[0046] The fixed part 31 is, for example, a bracket having mounting surfaces on the bottom surface and one side surface. The bottom surface is fixed to the upper surface of the base 2, and a linear guide 33 (for example, a carriage 33b described later) is attached to one side surface. The pair of fixed parts 31 are arranged such that the mounting surfaces on the side surfaces face each other with a gap in the X direction, and the floating part 32 is sandwiched from both sides in the X direction via the pair of linear guides 33.

[0047] The floating part 32 is a substantially T-shaped member having a horizontally plate-shaped arm part 32a extending in the X direction, a trunk part 32b hanging down from the central part of the lower surface of the arm part 32a, and lip parts 32c hanging down from both ends of the arm part 32a. The trunk part 32b is attached to the side surface of the fixed part 11 of the electro-dynamic actuator 10. A mounting surface perpendicular to the X direction is formed on the lip part 32c, and a linear guide 33 (for example, a rail 33a described later) is attached to this mounting surface with bolts.

[0048] The linear guide 33 is, like the linear guide 23 of the fixed part support mechanism 20, for example, a guideway type circulating linear bearing, and includes a rail 33a extending in the vibration direction (Z direction) and a carriage 33b capable of traveling on the rail 33a. One of the rail 33a and the carriage 33b is attached to each fixed part 31, and the other is attached to the floating part 32. A configuration in which the carriage 33b with a complex structure is attached to the fixed part 31 with less vibration is effective in reducing the failure rate. Also, attaching the rail 33a with a uniform mass distribution in the Z direction to the floating part 32 vibrating in the Z direction is effective in suppressing vibration noise.

[0049] The pair of buffer sections 34 are, for example, air springs, and are arranged side by side in the X direction with the trunk 32b of the floating section 32 in between, and are sandwiched between the base 2 and the arm section 32a. The buffer sections 34 reduce the transmission of vibrations from the floating section 32 to the fixed section 31, especially in the high frequency range, and also dampen the vibrations of the floating section 32. The vibration damping function of the air springs 34 can be achieved, for example, by providing a constriction in the flow path connecting the air springs 34 and the auxiliary tank. The buffer sections 34 may be formed from elastic and viscous elements, or viscoelastic elements, coupled in parallel or in series, similar to the buffer sections 24 of the fixed section support mechanism 20.

[0050] When the vibration testing device 1 is not operating (i.e., when only a static load is applied to the fixed part support mechanism 30), the air pressure of the air spring 34 is adjusted so that the height of the floating part 32 (and the fixed part 11 of the electrodynamic actuator 10 of the Z vibration excitation unit 7) is at a predetermined reference position (neutral position). Therefore, even if the height of the floating part 32 is temporarily shifted from the neutral position due to the dynamic load in the Z direction received from the Z vibration excitation unit 7, it is automatically returned to the neutral position by the restoring force of the air spring 34. In other words, the air spring 34 has a neutral return function.

[0051] However, the number, arrangement, and form of each part (fixed part 31, floating part 32, linear guide 33, and buffer part 34) constituting the fixed part support mechanism 30 are not limited to those of this embodiment.

[0052] The movable part support mechanism 40 more precisely restricts the movement direction of the movable part 12 of the Z-vibration unit 7 (specifically, the electrodynamic actuator 10) to the Z-direction (i.e., the vibration direction), thereby improving the vibration accuracy of the Z-vibration unit 7. As a result, vibration noise in the X-direction and Y-direction (i.e., non-vibration direction) of the movable part 12 is reduced.

[0053] The movable part support mechanism 40 comprises a movable frame 43 and multiple sets (for example, four sets) of fixed frames 41 and linear guides 42. The multiple sets of fixed frames 41 and linear guides 42 are arranged around the movable frame 43, for example, at equal intervals.

[0054] The fixed frame 41 is, for example, a bracket, similar to the fixed part 31 of the fixed part support mechanism 30, with its bottom surface fixed to the upper surface of the fixed part 11 of the electrodynamic actuator 10, and a linear guide 42 (for example, a carriage 42b described later) attached to one side.

[0055] The movable frame 43 is attached to the tip of the movable part 12 of the electrodynamic actuator 10. The movable frame 43 substantially extends the length of the portion of the movable part 12 of the electrodynamic actuator 10 that protrudes from the upper surface of the fixed part 11. This makes it possible to support the movable part 12 from the side by the movable part support mechanism 40.

[0056] The linear guide 42, like the linear guide 23 of the fixed support mechanism 20, is, for example, a guideway-type circulating linear bearing and comprises a rail 42a extending in the vibration direction (Z direction) and a carriage 42b that can travel on the rail 42a. One of the rail 42a and the carriage 42b is attached to each fixed frame 41, and the other is attached to the movable frame 43. Attaching the structurally complex carriage 42b to the fixed frame 41, which experiences less vibration, is effective in reducing the failure rate. Furthermore, attaching the rail 42a, which has a uniform mass distribution in the Z direction, to the movable frame 43, which vibrates significantly in the Z direction, is effective in suppressing vibration noise.

[0057] Figure 10 is a perspective view of the slide coupling mechanism 70 and the vibrating table 3 from below. A recess 3a for housing the slide coupling mechanism 70 is formed on the lower surface of the vibrating table 3. By providing the recess 3a, the center of gravity of the vibrating table 3 is lowered, and the moment around the horizontal axis (i.e., the tipping moment) can be reduced. In addition, it becomes possible to support the vibrating table 3 with higher rigidity (i.e., with higher positional accuracy), improving the excitation accuracy.

[0058] The slide coupling mechanism 70 includes a plurality (for example, four) cross guides 71. Each cross guide 71 includes two linear guides 72 whose travel directions are perpendicular to each other (for example, an X linear guide 72X that can travel in the X direction and a Y linear guide 72Y that can travel in the Y direction). One of the linear guides 72 of the cross guide 71 is attached to the upper surface of the movable frame 43 of the movable part support mechanism 40, and the other is attached to the bottom surface of the vibrating table 3.

[0059] The linear guide 72, like the linear guide 23 of the fixed support mechanism 20, is, for example, a guideway-type circulating linear bearing and comprises a rail 72a extending in the direction of travel and a carriage 72b that can travel on the rail 72a. The carriage 72b has mounting holes formed in it for directly fixing two carriages 72b together, similar to the carriages 61b and 62b of the slide coupling mechanism 60, so that the two carriages 72b are fixed to each other directly (i.e., without using mounting plates or the like) by bolts, for example. This configuration makes the slide coupling mechanism 70 lighter (reduces inertia) and improves the excitation performance of the Z excitation unit 7.

[0060] The cross guides 71 include Type A cross guides 71A and Type B cross guides 71B. In Type A cross guides 71A, the rail 72a of the X linear guide 72X is attached to the movable frame 43 of the movable part support mechanism 40, and the rail 72a of the Y linear guide 72Y is attached to the vibrating table 3. In Type B cross guides 71B, the rail 72a of the Y linear guide 72Y is attached to the movable frame 43, and the rail 72a of the X linear guide 72X is attached to the vibrating table 3. Note that all of the cross guides 71 may be Type A cross guides 71A (or Type B cross guides 71B).

[0061] In this embodiment, type A cross guides 71A and type B cross guides 71B are arranged alternately. That is, type B cross guides 71B are placed next to type A cross guides 71A, and type A cross guides 71A are placed next to type B cross guides 71B. This alternating arrangement makes the mass distribution of the entire slide coupling mechanism 70 uniform, thereby reducing vibration noise.

[0062] Figure 11 is a block diagram showing the schematic configuration of the control system 1a of the vibration testing apparatus 1. The control system 1a includes a control unit 81 that controls the operation of the entire vibration testing apparatus 1, a measurement unit 82 that performs various measurements based on signals from various detectors provided in the vibration testing apparatus 1, and an interface unit 83 that performs input and output to the outside. The measurement unit 82 and the interface unit 83 are each connected to the control unit 81 so as to be able to communicate with it.

[0063] The control unit 81 is connected to the electrodynamic actuators 10 of each vibration unit 5, 6, and 7 via a drive device 10a that supplies drive current to the electrodynamic actuators 10.

[0064] The measurement unit 82 is equipped with a three-axis vibration sensor (three-axis vibration pickup) 3s attached to the vibration table 3, and amplifies and digitally converts the signal from the three-axis vibration sensor 3s (e.g., acceleration signal and velocity signal) and transmits it to the control unit 81. The three-axis vibration sensor may be configured to output a digital signal. The three-axis vibration sensor 3s independently detects vibrations in the X, Y, and Z directions. The measurement unit 82 also calculates various measured values ​​representing the vibration state of the vibration table 3 (e.g., velocity, acceleration, jerk, vibration acceleration level (vibration level), amplitude, and power spectral density, including one or more) based on the signal from the three-axis vibration sensor 3s and transmits them to the control unit 81. The control unit 81 can excite the vibration table 3 with a desired amplitude and frequency by controlling the magnitude and frequency of the drive current supplied to the drive coils of each excitation unit 5, 6, and 7 based on the excitation waveform input via the interface unit 83 and the measured values ​​input from the measurement unit 82.

[0065] The interface unit 83 includes, for example, one or more user interfaces for input and output with the user, a network interface for connecting to various networks such as a LAN (Local Area Network), and various communication interfaces such as USB (Universal Serial Bus) and GPIB (General Purpose Interface Bus) for connecting to external devices. The user interface also includes, for example, one or more various input / output devices such as various operation switches, displays, LCDs (liquid crystal displays), pointing devices such as mice and touchpads, touchscreens, video cameras, printers, scanners, buzzers, speakers, microphones, and memory card readers / writers.

[0066] The control unit 81 may be connected to the server 85 via the network interface of the interface unit 83 and the network 84 (for example, LAN and / or the Internet). In this case, the control unit 81 can acquire setting information such as excitation waveforms stored in the server 85 and control the driving of the electrodynamic actuators 10 of each excitation unit 5, 6, and 7 based on this setting information. The control unit 81 can also store measurement results representing the vibration state of the vibration table 3 acquired from the measurement unit 82 in the server 85. This enables centralized management of setting information and measurement results for multiple vibration test devices 1 connected to the server 85.

[0067] The linear guide sections 50X and 50Y according to the embodiments of the present invention described above support a movable frame 53, which is long in the excitation direction and coupled to the movable section 12 of the electrodynamic actuator 10, in a manner that allows it to slide in the excitation direction. This makes it possible to secure a sufficient support length in the excitation direction (for example, by supporting the movable frame 53 with a plurality of carriages 52b arranged in the excitation direction), thereby improving the straight-line accuracy of the excitation units 5 and 6.

[0068] Furthermore, by providing the linear guide sections 50X and 50Y independently of the electrodynamic actuator 10, even when it is necessary to install the vibrating table 3 at a location far from the electrodynamic actuator 10, it becomes possible to support the movable parts 5m and 6m of the excitation units 5 and 6 with high rigidity near the vibrating table 3. As a result, it becomes possible to excite the vibrating table 3 with higher precision in the excitation direction.

[0069] In the electrodynamic three-axis vibration exciter 1 described in Patent Document 1 (International Publication No. 2017 / 122770), the movable part 120 of the electrodynamic actuator 100A connected to the vibrating table 400 is supported by the movable part support mechanism 140. Therefore, the movable part support mechanism 140 receives moments generated by the vibrating table 3 and moments generated by the Z-vibration unit 300. However, since the movable part support mechanism 140 is attached to the fixed part 110 of the electrodynamic actuator 100A, which has a relatively complex structure, low rigidity, and is unstable, it is unable to withstand these moments with sufficiently high rigidity, which contributes to the vibration distribution on the vibrating table and crosstalk.

[0070] In contrast, the movable frames 53 of the linear guide sections 50X and 50Y in this embodiment are supported by fixed frames 51X and 51Y, which are structural members that are more structurally simple (for example, integrally formed), highly rigid, and stable, and are firmly fixed to the base 2. Therefore, the linear guide sections 50X and 50Y in this embodiment are able to support the movable sections 5m and 6m (more directly, the movable frames 53) of the excitation units 5 and 6 with higher rigidity and stability relative to the base 2 than the movable section support mechanism 140 of Patent Document 1. In the vibration testing apparatus 1 according to the embodiment of the present invention, the moments generated by the Z excitation unit 7 and the moments generated on the vibration table 3 are firmly received by the linear guide sections 50X and 50Y, so that the vibration distribution and crosstalk on the vibration table are reduced.

[0071] (First Modified Example) Figure 12 is a perspective view of the slide coupling mechanism 60A and the linear guide section 50YA according to the first modified example of the embodiment of the present invention.

[0072] In the slide coupling mechanism 60 of the embodiment described above, the first linear guide 61 (in the X direction) is attached to the movable frame 53 of the linear guide section 50Y, and the second linear guide 62 (in the Z direction) is attached to the vibrating table 3. In contrast, in the slide coupling mechanism 60A of the first modified example, the second linear guide 62 is attached to the movable frame 53A of the linear guide section 50YA, and the first linear guide 61 is attached to the vibrating table 3.

[0073] The movable frame 53A of the first modified example has a rectangular plate-shaped mounting plate 53h fixed vertically to the front end (Y-direction tip) of the main plate 53a, and a plurality of triangular plate-shaped ribs 53i (for example, three pairs, upper and lower) connecting the main plate 53a and the mounting plate 53h. The rails 62a of the second linear guide 62 are attached to the mounting plate 53h. One end of each pair of ribs 53i connects the upper surface of the main plate 53a to the upper part of the mounting plate 53h, and the other end connects the lower surface of the main plate 53a to the lower part of the mounting plate 53h. The three pairs of ribs 53i are fixed to the mounting plate 53h, for example, directly behind the rails 62a of each second linear guide 62.

[0074] The range in the X direction to which the rails 62a of the three second linear guides 62 are attached is shorter than the length of the rail 61a of the first linear guide 61 and less than or equal to the width of the main plate 53a. For this reason, the movable frame 53A of the first modified example is not provided with a widened portion 53f (Figure 7).

[0075] The first modified slide coupling mechanism 60A makes it possible to use a vibrating table 3 that is thinner in thickness (Y-direction dimension) than the length of the rail 62a of the second linear guide 62 by positioning the rail 61a of the first linear guide 61, which extends in the horizontal direction (X-direction), on the vibrating table 3 side.

[0076] (Second Modification) Figure 13 is a perspective view of the slide coupling mechanism 60B and the linear guide section 50YB according to a second modification of the embodiment of the present invention.

[0077] The slide coupling mechanism 60 of the above-described embodiment comprises one first linear guide 61(X) and a plurality (for example, three) second linear guides 62(Z). In contrast, the slide coupling mechanism 60B of the second modified example comprises a plurality (for example, two) first linear guides 61B and a plurality (for example, three) second linear guides 62B(Z).

[0078] The first linear guide 61B comprises one rail 61a and multiple (for example, three) carriages 61b that can travel on the rail 61a. The sliding coupling mechanism 60B comprises the same number of second linear guides 62B as the carriages 61b of the first linear guide 61B. The second linear guide 62B also comprises the same number of carriages 62b as the first linear guide 61B.

[0079] Multiple first linear guides 61B are arranged in a vertical line, and their rails 61a are attached to the mounting surface 53g of the movable frame 53B. In addition, the rails 62a of multiple second linear guides 62 are attached, for example, at equal intervals to the side of the vibrating table 3 facing the Y excitation unit 6.

[0080] The slide coupling mechanism 60B of the second modified example includes a plurality of first linear guides 61B arranged in parallel, which makes it possible to excite the vibrating table 3 with higher rigidity (i.e., with higher precision).

[0081] (Third Modification) Figure 14 is a left side view (partial cross-sectional view) of the linear guide section 50YC and the slide coupling mechanism 60 according to a third modification of the embodiment of the present invention.

[0082] In the linear guide section 50Y of the above-described embodiment, the movable frame 53 is slidably supported only by a linear guide 52 attached to its lower surface. In contrast, in the linear guide section 50YC of the third modified example, the movable frame 53C is supported by a plurality of linear guides 52, one or more of which are attached to its lower surface, upper surface, and both sides.

[0083] The upper end of the arm portion 51YCaa of the fixed frame 51YC is provided with a rectangular cylindrical portion 51Yt that extends in the Y direction through which the movable frame 53C passes. One or more rails 52a and carriages 52b of the linear guide 52 (for example, carriages 52b) are attached to each of the four inner surfaces of the cylindrical portion 51Yt, and the other is attached to the lower surface, upper surface, and both sides of the movable frame 53C.

[0084] The upper and lower surfaces of the movable frame 53C of the linear guide section 50YC in the third modified example may be configured similarly to the lower surface of the movable frame 53 in the embodiment described above (Figure 7). That is, the movable frame 53C may have six ribs 53e, 53d, 53e (i.e., three on each of the upper and lower surfaces) that protrude from the upper and lower surfaces of the main plate 53a and extend in the Y direction. On each of the upper and lower surfaces, a pair of linear guides 52 aligned in the Y direction are housed in the recesses formed between rib 53d and one rib 53e, and in the recesses formed between rib 53d and the other rib 53e.

[0085] As shown in Figure 14, a pair of linear guide rails 52a or carriages 52b are attached to both sides of the movable frame 53C, respectively, aligned in the Y direction. In the third modified example, multiple linear guides 52, each consisting of one rail 52a and one carriage 52b, are used in the direction of travel, but instead, a single linear guide consisting of one long rail and multiple carriages may be used.

[0086] The above describes the embodiments of the present invention. The embodiments of the present invention are not limited to those described above, and various modifications are possible. For example, configurations that appropriately combine the configurations of embodiments etc. explicitly shown herein and / or the configurations of embodiments etc. that are obvious to those skilled in the art from the description herein are also included as embodiments of the present invention.

[0087] In the above embodiments and modifications, a guideway-type circulating linear bearing is used as the linear guide, but the present invention is not limited to this configuration. For example, other types of rolling guides (linear bearings), such as linear bushings (ball bushings) and ball splines, may be used. In particular, for the linear guides 23 of the fixed support mechanism 20 and the linear guides 33 of the fixed support mechanism, which have small amounts of movement, sliding guides or hydrostatic guides may be used.

[0088] Furthermore, in particular, the linear guides 42 of the movable part support mechanism 40 that supports the vibrating part, the linear guides 52 of the linear guide sections 50X and 50Y, the first linear guide 61 and second linear guide 62 of the slide coupling mechanism 60, and the linear guide 72 of the slide coupling mechanism 70 may be equipped with eight rolling paths in which small-diameter rolling elements circulate, and eight-row linear guides may be used, which support the load with more rolling elements than a normal linear guide with four rolling paths. By using eight-row linear guides with high straight-line accuracy, the excitation accuracy is improved.

[0089] <Summary> The embodiments of the present invention described above will be summarized below.

[0090] According to one embodiment of the present invention, a vibration testing apparatus is provided, comprising a base, a vibrating table on which a test specimen is attached, and a vibration unit for vibrating the vibrating table in a predetermined vibration direction. The vibration unit comprises a linear actuator mounted on the base that is capable of outputting reciprocating linear motion in the vibration direction, and a linear guide unit mounted on the base that is capable of transmitting the reciprocating linear motion output from the linear actuator to the vibrating table (1A configuration).

[0091] In the vibration testing apparatus of the first configuration A, the linear guide section may include a movable frame driven by the linear actuator and a slider that limits the direction of movement of the movable frame to the excitation direction (first configuration B).

[0092] By providing a linear guide section (more specifically, a slider), the linear accuracy of the excitation unit can be improved.

[0093] In the vibration testing apparatus of the first configuration B described above, the slider may be equipped with one or more linear guides, and the linear guide may be equipped with a rail extending in the vibration direction and one or more carriages that can travel on the rail (first configuration C).

[0094] In the vibration testing apparatus of the first configuration C, the slider may be provided with a plurality of carriages arranged in the excitation direction (first configuration D).

[0095] By providing multiple carriages with sliders arranged in the excitation direction, the moment stiffness around an axis perpendicular to the excitation direction is improved.

[0096] In the vibration testing apparatus of the first configuration C, the slider may have multiple carriages that are not on the same straight line (first configuration E).

[0097] By having multiple carriages that are not collinear with the slider (i.e., the movable frame is supported by multiple carriages arranged in two dimensions), the moment stiffness around each of the three orthogonal axes (especially around the axis in the excitation direction) is improved.

[0098] In any of the vibration testing apparatus configurations 1C, 1D, and 1E, the linear guide may be a linear bearing such as a guideway-type circulating linear bearing (second configuration).

[0099] By employing a guideway-type circulating linear bearing in the linear guide, the linear accuracy of the excitation unit can be improved.

[0100] In any of the vibration testing apparatuses described in configurations 1B, 1C, 1D, 1E, and 2, the movable frame may be substantially plate-shaped (configuration 3A).

[0101] By making the movable frame roughly plate-shaped, it is possible to reduce the weight of the movable frame while ensuring a sufficient mounting surface area for the linear guide.

[0102] In the vibration testing apparatus of the third configuration A (but limited to the configuration of the first configuration C), the one or more linear guides may include a set of first linear guides attached to one surface of the movable frame (third configuration B).

[0103] In the vibration testing apparatus of the third B configuration, the set of first linear guides may include a plurality of carriages that are not on the same straight line (third C configuration).

[0104] In the vibration testing apparatus of the 3B or 3C configuration described above, the set of first linear guides may include a plurality of carriages aligned in the excitation direction and a plurality of carriages aligned in a direction perpendicular to the excitation direction (fourth configuration).

[0105] By incorporating multiple carriages where the sliders are not on the same straight line, the moment stiffness around each of the three orthogonal axes is improved.

[0106] In any of the vibration testing apparatus configurations 3B, 3C, and 4, the first linear guide may comprise a single rail and a single carriage (configuration 5A).

[0107] In the vibration testing apparatus of configuration 5A, the set of first linear guides may include four first linear guides arranged in two rows of two (configuration 5B).

[0108] In this case as well, since the movable frame is supported by multiple carriages arranged in two dimensions, the moment stiffness around each of the three orthogonal axes is improved.

[0109] In the vibration testing apparatus according to any of the configurations 1A to 5B described above (however, limited to those including the configuration 3A described above), the movable frame may have a main plate in the shape of a substantially rectangular plate and a first mounting plate that is fixed vertically to the rear end of the main plate and attached to the movable part of the linear actuator (configuration 6A).

[0110] In the vibration testing apparatus of configuration 6A described above, the movable frame may have ribs connecting the main plate and the first mounting plate (configuration 6B).

[0111] In the vibration testing apparatus of configuration 6A described above, the movable frame may have ribs that protrude from one surface of the main plate and extend in the vibration direction, connecting the main plate and the first mounting plate (configuration 6C).

[0112] By providing ribs with this configuration on the movable frame, it becomes possible to reinforce the main plate, the first mounting plate, and the connection between the main plate and the first mounting plate all at once.

[0113] In the vibration testing apparatus of configuration 6B or 6C, the movable frame may have a plurality of ribs (configuration 6D).

[0114] In the vibration testing apparatus of configuration 6A, the movable frame may have a plurality of ribs that protrude from one surface of the main plate and extend in the vibration direction, connecting the main plate and the first mounting plate, and the first linear guide may be housed in a recess formed between two adjacent ribs (configuration 6E).

[0115] This configuration makes it possible to reinforce the movable frame and arrange the first linear guide with high spatial efficiency.

[0116] In any of the vibration testing apparatus configurations 1A to 6E described above, the linear guide section may include a fixed frame fixed to the base (configuration 7A).

[0117] In the vibration testing apparatus of the 7A configuration (however, limited to those including the 3B configuration), the excitation direction is horizontal, the fixed frame has a body portion and an arm portion that extends diagonally upward from the body portion toward the vibration table, and the pair of first linear guides may be attached to the upper surface of the arm portion (7B configuration).

[0118] With this configuration, even when it is necessary to position the body at a distance from the vibration table in the excitation direction to avoid interference with the fixed support mechanism 30 of the above embodiment, for example, the first linear guide can be positioned close to the vibration table to support the movable frame near the vibration table, thereby improving the straight-line accuracy of the excitation unit.

[0119] In the vibration testing apparatus with the configuration of 7A described above, the linear guide section may include a fixed frame fixed to the base, and the fixed frame may have a cylindrical portion through which the movable frame passes (configuration of 8A).

[0120] In the vibration testing apparatus of configuration 8A, either the rail or the carriage of the linear guide may be attached to a plurality of surfaces (for example, two, three, or four surfaces) of the movable frame perpendicular to the excitation direction (configuration 8B).

[0121] In the vibration testing apparatus of configuration 8B described above, the rail of the linear guide and the other of the carriage may be attached to the inner surface of the cylindrical portion (configuration 8C).

[0122] This configuration allows the movable frame to be supported with high rigidity by linear guides on multiple surfaces, improving the linear accuracy of the excitation unit.

[0123] In any of the vibration testing apparatuses described in configurations 1A to 8C, a second excitation unit may be provided that excites the vibration table in a second excitation direction perpendicular to the excitation direction (configuration 9A).

[0124] In the vibration testing apparatus of configuration 9A described above, the excitation unit may be provided with a sliding coupling mechanism that slidably connects the movable frame of the linear guide section and the vibration table in the second excitation direction (configuration 9B).

[0125] This configuration makes it possible to excite the vibrating table with high precision in multiple directions, including the first and second excitation directions.

Claims

1. A vibration testing apparatus comprising: a base; a vibrating table on which a test specimen is attached; and an excitation unit for excitation of the vibrating table in a predetermined excitation direction, wherein the excitation unit comprises: a linear actuator mounted on the base capable of outputting reciprocating linear motion in the excitation direction; and a linear guide mounted on the base capable of transmitting the reciprocating linear motion output from the linear actuator to the vibrating table, wherein the linear guide comprises: a movable frame driven by the linear actuator; and a slider that restricts the direction of movement of the movable frame to the excitation direction, wherein the slider comprises one or more linear guides, and the linear guide comprises: a rail extending in the excitation direction; and one or more carriages capable of traveling on the rail, and the slider comprises a plurality of carriages arranged in the excitation direction.

2. The vibration testing apparatus according to claim 1, wherein the linear guide is a guideway type circulating linear bearing.

3. The vibration testing apparatus according to claim 1, wherein the movable frame is substantially plate-shaped, and the one or more linear guides include a pair of first linear guides attached to one surface of the movable frame, and the pair of first linear guides comprises a plurality of carriages that are not on the same straight line.

4. The vibration testing apparatus according to claim 3, wherein the set of first linear guides comprises a plurality of carriages aligned in the excitation direction and a plurality of carriages aligned perpendicular to the excitation direction.

5. The vibration testing apparatus according to claim 3, wherein each of the first linear guides comprises a single rail and a single carriage, and the set of first linear guides comprises four of the first linear guides arranged in two rows of two.

6. The vibration testing apparatus according to claim 3, wherein the movable frame comprises a main plate in the shape of a substantially rectangular plate, a first mounting plate fixed perpendicularly to the rear end of the main plate and attached to the movable part of the linear actuator, and a plurality of ribs protruding from one surface of the main plate and extending in the vibration direction, connecting the main plate and the first mounting plate, and the first linear guides are housed in recesses formed between two adjacent ribs.

7. The vibration testing apparatus according to claim 3, wherein the excitation direction is horizontal, the linear guide section comprises a fixed frame fixed to the base, the fixed frame has a body section and an arm section extending diagonally upward from the body section toward the vibration table, and the pair of first linear guides is attached to the upper surface of the arm section.

8. The vibration testing apparatus according to claim 1, wherein the linear guide section comprises a fixed frame fixed to the base, the fixed frame has a cylindrical portion through which the movable frame passes, one of the rails and carriages of the linear guide is attached to each of the four surfaces of the movable frame perpendicular to the vibration direction, and the other of the rails and carriages of the linear guide is attached to the inner surface of the cylindrical portion.

9. The vibration testing apparatus according to any one of claims 1 to 8, comprising a second excitation unit that excites the vibration table in a second excitation direction perpendicular to the excitation direction, wherein the excitation unit comprises a sliding coupling mechanism that slidably connects the movable frame of the linear guide section and the vibration table in the second excitation direction.

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