WO2016189730A1 - Dynamic damper, vehicle seat, and vehicle accessory - Google Patents

Abstract

A dynamic damper (8) is provided with: a base section (8a); a weight unit (8d); a first elastic support unit (91) for elastically supporting the weight unit (8d) with respect to the base section (8a) at a first support position (P1) with a first spring constant (k1); and a second elastic support unit (92) for elastically supporting the weight unit (8d) with respect to the base section (8a) at a second support position (P2) that is separated from the first support position (P1) in a first direction with a second spring constant (k2) that differs from the first spring constant (k1).

Description

Dynamic dampers, vehicle seats, and vehicle equipment

The present invention relates to a dynamic damper, and a vehicle seat and a vehicle equipment equipped with the dynamic damper.

Vibration generated in vehicle equipment such as a vehicle seat and a battery needs to be damped as much as possible so that the amplitude does not become too large.
In particular, since vibrations with a frequency of 20 Hz or less in the vehicle seat are easily felt by the human body, it is desired that the vibration is attenuated so that the comfort of the seated passenger is maintained.
Patent Document 1 describes that a dynamic damper is provided in a seat back in order to attenuate a large vibration generated in a vehicle seat.
In other words, a dynamic damper is provided in the vehicle seat, and the natural frequency of the dynamic damper is adjusted to the frequency of a large vibration generated in the seat, thereby suppressing the vibration at that frequency.

Japanese Utility Model Publication No. 1-167926

By the way, in vehicle equipment such as a vehicle seat and a battery, which are equipped on a vehicle, vibrations from a plurality of vibration sources are transmitted through the vehicle structure (such as a vehicle). For this reason, there are cases where large vibrations are likely to occur not only at one frequency but also at a plurality of (for example, two) frequencies.
In this case, it is difficult to suppress large vibrations at a plurality of frequencies with a single dynamic damper, and it is necessary to use a plurality of dynamic dampers that match the natural frequency for each vibration frequency.
Therefore, an increase in cost and an increase in the mass of vehicle equipment have been incurred, and improvements have been desired.

Therefore, an object of the present invention is to provide a dynamic damper, a vehicle seat, and a vehicle equipment that can attenuate vibration while suppressing an increase in cost and an increase in mass.

According to the first aspect of the present invention, the base portion, the weight unit, and the first elastic support unit that elastically supports the weight unit at the first support position with the first spring constant with respect to the base portion. The second elasticity for elastically supporting the weight unit with respect to the base portion at a second support position separated from the first support position in the first direction by a second spring constant different from the first spring constant. And a dynamic damper comprising a support unit.
According to the second aspect of the present invention, the base portion, the weight unit, the first elastic support unit that elastically supports the weight unit at the first support position with respect to the base portion, and the weight relative to the base portion. A second elastic support unit that elastically supports the unit at a second support position that is spaced apart from the first support position in the first direction; and a support that allows at least the first support position to move in the first direction. A dynamic damper having a position moving mechanism is provided.
According to a third aspect of the present invention, there is provided a vehicle seat that includes a seat back frame and a cushion frame and is mounted on a vehicle, wherein at least one of the seat back frame and the cushion frame is provided with the first or first seat. A vehicle seat is provided in which the dynamic damper according to the second aspect is attached with a first direction as a direction perpendicular to the width direction of the vehicle seat.
According to a fourth aspect of the present invention, there is provided a vehicle equipment mounted on a vehicle, the vehicle equipment having the dynamic damper according to the first or second aspect attached thereto.

The present invention has the effect of suppressing the increase in cost and mass and damping the vibration.

FIG. 1 is a perspective view for explaining a dynamic damper 8 that is Example 1 of a dynamic damper according to an embodiment and a seat 1 including the same. FIG. 2 is a partially enlarged view of FIG. 1 for explaining the dynamic damper 8 provided in the seat 1. FIG. 3 is a schematic plan view for explaining the dynamic damper 8. FIG. 4 is a diagram illustrating a basic model of a dynamic damper with two degrees of freedom. 5A and 5B are graphs for explaining the characteristics of the dynamic damper 8. FIG. 5A shows the translational component of the displacement, and FIG. 5B shows the rotational component of the displacement. FIG. 6 is a perspective view for explaining the dynamic damper 18 of the second embodiment. FIG. 7 is a three-side view for explaining the elastic support portion 21a included in the dynamic damper 18. As shown in FIG. FIG. 8 is a perspective view for explaining the frame body 52 of the seat 51 provided with the dynamic damper 18. FIG. 9 is a partially broken perspective view showing the vehicle 60 on which the battery 61 having the dynamic damper 18 is mounted.

The dynamic damper and the like according to the embodiment will be described with reference to FIGS.

(Example 1)
As a first embodiment, a dynamic damper 8 and a vehicle seat 1 including the dynamic damper 8 (hereinafter referred to as a seat 1) will be described.
First, a schematic configuration of the sheet 1 will be described with reference to FIG. In FIG. 1, the front, rear, left, right, top, and bottom directions are indicated as FR, RR, LH, RH, UP, and LWR with the forward direction of the vehicle as the front in a state where the seat 1 is attached to the floor F of the vehicle. . The vehicle is, for example, a vehicle when the vehicle 60 (see FIG. 9) is an automobile.
The seat 1 is a seat for single passengers, but may be a seat for multiple passengers wide in the left-right direction (width direction).

As shown in FIG. 1, a pair of fixed rails 41 are attached to the floor F of the vehicle so as to be spaced apart in parallel in the left-right direction.
The seat 1 is attached to the pair of fixed rails 41 so as to be movable in the front-rear direction.

The seat 1 includes a frame body 2 that is a framework and a cushion body 31 that is provided so as to wrap the frame body 2. In FIG. 1, the frame body 2 is indicated by a solid line, and the outer shape of the cushion body 31 is indicated by a two-dot chain line.
The frame body 2 includes a pair of movable rail portions 3 and 3 engaged and mounted on a pair of fixed rails 41 and 41, and a frame-like cushion frame 4 connected so as to straddle the upper side of the movable rail portions 3 and 3, respectively. And having. Further, the frame body 2 has an elongated frame-like seat back frame 5 that is rotatably connected around a rotation axis CL5 extending in the left-right direction at the rear portion of the cushion frame 4.
The cushion body 31 includes a seat cushion 32 that is a seating portion formed by accommodating the cushion frame 4 therein, and a seatback cushion 33 that is a backrest portion formed by accommodating the seat back frame 5 therein. It is configured.

That is, the seat 1 includes a seat cushion portion 1A as a seat portion including the cushion frame 4 and the seat cushion 32, and a seat back portion 1B as a backrest portion including the seat back frame 5 and the seat back cushion 33. It is configured.
The seat back portion 1B can be raised and lowered within a predetermined angle range around the rotation axis CL5 with respect to the seat cushion portion 1A.
FIG. 1 shows a standing state of the seat back portion 1B.

A pair of headrest holders 6 and 6 are provided on the upper portion of the seat back frame 5 so as to be separated from each other in the left-right direction.
A headrest frame 7 is attached to the headrest holders 6 and 6 so as to be freely inserted and removed from above.
The upper portion of the headrest frame 7 is wrapped in a headrest cushion 34. A headrest 35 is configured including the headrest frame 7 and the headrest cushion 34. In FIG. 1, the outer shape of the headrest cushion 34 is indicated by a two-dot chain line.

The seat back frame 5 includes a pair of side frames 5a and 5a that are separated from each other in the left-right direction and are arranged in parallel so as to extend in the up-down direction in the standing state shown in FIG.
The tip portions of the pair of side frames 5a, 5a are connected by a top frame 5b extending in the left-right direction.
The pair of headrest holders 6 and 6 described above are attached to the top frame 5b.

The pair of side frames 5a, 5a are connected by a middle frame 5c extending left and right at the center. Further, the side frames 5a and 5a are connected by a lower frame 5d extending in the left and right direction at the lower part.
The seat back frame 5 has a pair of side frames 5a and 5a between the top frame 5b and the middle frame 5c, and has cross frames 5e and 5f that are spaced apart in the vertical direction.
The cross frames 5e and 5f are connected by stays 5g and 5h extending along the side frame 5a.
The stays 5g and 5h are provided to be spaced apart in parallel in the left-right direction.

The dynamic damper 8 is supported by the cross frame 5e and the stays 5g and 5h.
That is, the seat 1 has a dynamic damper 8 on the seat back frame 5. For example, as shown in FIG. 1, the dynamic damper 8 is provided at a position that does not interfere with the headrest frame 7 attached to the seat back portion 1 </ b> B, which is a substantially central portion of the seat back frame 5 in the left and right and upper and lower sides. ing.

Next, details of the dynamic damper 8 will be described with reference to FIGS.
FIG. 2 is an enlarged view showing the dynamic damper 8 and members in the vicinity thereof in FIG. In FIG. 2, the extending direction of the cross frame 5e is the Y direction, the extending direction of the stays 5g and 5h is the Z direction, and the direction orthogonal to the Y direction and the Z direction is the X direction.
The X direction, the Y direction, and the Z direction generally correspond to the front-rear direction, the left-right direction, and the up-down direction, respectively, in the standing state of the seat back portion 1B.
FIG. 3 is a schematic diagram for explaining the dynamic damper 8, and is a plan view seen from the front side in the X direction in FIG. In FIG. 3, the base plate 8a described below has a central upper part and a central lower part broken to avoid drawing complexity.

The dynamic damper 8 includes a rectangular plate-like base plate 8a that is a base portion, a weight unit 8d, and an elastic support unit 9 that elastically supports the weight unit 8d with respect to the base plate 8a. In this example, the elastic support unit 9 has four elastic support portions 9a to 9d.
Specifically, the base plate 8a is attached to the cross frame 5e and the stays 5g and 5h by fasteners 8e such as bolts and nuts.
L-shaped brackets 8b1 to 8b4 are attached to the four corners of the base plate 8a, and the weight unit 8d is supported via elastic support portions 9a to 9d connected to the brackets 8b1 to 8b4, respectively.
The elastic support portions 9a to 9d have at least elastic members 8c1 to 8c4, respectively.
In this example, coil springs are used as the elastic members 8c1 to 8c4. Hereinafter, they are also referred to as coil springs 8c1 to 8c4.

More specifically, elongated holes 8a1 to 8a4 extending in the Y direction are formed at the four corners of the base plate 8a (FIG. 2). Brackets 8b1 to 8b4 are attached to the base plate 8a by bolts 8a5 passed through the long holes 8a1 to 8a4 and nuts (not shown) that are screwed into the bolts 8a5.
Accordingly, the mounting positions of the brackets 8b1 to 8b4 with respect to the base plate 8a can be adjusted according to the length of the long holes 8a1 to 8a4 in the Y direction.

Hook plates 8b5 to 8b8 having through holes are attached to the brackets 8b1 to 8b4.
The coil springs 8c1 to 8c4 as elastic members are attached to the brackets 8b1 to 8b4 via the hook plates 8b5 to 8b8 with hooks at one end thereof hooked into through holes of the hook plates 8b5 to 8b8, respectively.

The weight unit 8d includes a weight body 8d2 integrated so that a plurality of rectangular plate-shaped weights 8d1 are stacked to form a columnar shape, and a plurality of L-shaped hold brackets 8d3.
More specifically, the weight 8d1 is formed in two pairs of through-holes that are spaced apart in the width direction at positions close to both ends in the longitudinal direction (the pair of through-holes are formed at the front and back below the weight 8d1 in FIG. And the other pair of through-holes means two holes formed on the front and back above the weight 8d1).
The weight unit 8d has a plurality of weights 8d1 (eight in this example) overlapped, sandwiched by two pairs of hold brackets 8d3 from both sides in the thickness direction, and bolts 8d4 passing these through two pairs of through holes. , 8d6 and nuts 8d5, 8d7 screwed thereto, are integrally formed.

A hook holder 8d7 for hooking hook portions of the coil springs 8c1 to 8c4 is attached to the hold bracket 8d3 attached to the weight unit 8d.
In the weight unit 8d, one hook portion of the coil springs 8c1 to 8c4 is hung on each hook holder 8d7.
Thereby, the weight unit 8d is elastically supported with respect to the base plate 8a.
In this example, the elastic support portions 9a to 9d include hook plates 8b5 to 8b8, coil springs 8c1 to 8c4, and a hook holder 8d7, respectively.

In this way, the weight body 8d2 is elastically supported at the support positions P1 and P2 to which the two pairs of hold brackets 8d3 are attached.
Here, the support position connected via the coil springs 8c1 and 8c2 is referred to as a support position P1, and the support position connected via the coil springs 8c3 and 8c4 is referred to as a support position P2.
The coil springs 8c1 to 8c4 are attached such that their respective axes are oriented in the Y direction.

As shown in FIG. 3, the support position P1 and the support position P2 are separated from each other in the longitudinal direction of the weight body 8d2. In the longitudinal direction of the weight body 8d2, the support position P1 and the support position P2 may be set as positions that sandwich the center of gravity G of the weight unit 8d. In other words, when the support position P1 and the support position P2 are viewed from the direction orthogonal to the separation direction, the center of gravity of the weight unit 8d is the first support position P1 and the second support position. It is set to be located between P2.
The two pairs (four in total) of the hold brackets 8d3 are in positions symmetrical with respect to the center line CL8 of the dynamic damper 8.
Accordingly, the support positions P1 and P2 of the one end face 8d2a in the width direction of the weight body 8d2 and the support positions P1 and P2 of the other end face 8d2b are the support positions P1 and the support positions P2 in the longitudinal direction of the weight body 8d2. In the same position.
A distance in the longitudinal direction between the support position P1 and the support position P2 is a distance La. The length in the longitudinal direction of the weight body 8d2 is a distance h.
The posture of the weight body 8d2 in the dynamic damper 8 is set so that the longitudinal direction of the weight body 8d2 is along the pair of side frames 5a and 5a arranged side by side.

In the longitudinal direction of the weight 8d2, the support position P1 is set to a position close to one longitudinal end 8d2c of the weight 8d2, and the support position P2 is set to a position close to the other long end 8d2d.
This is because the weight body 8d2 is supported in a stable manner via the elastic support portions 9a to 9d because the longitudinal direction of the weight body 8d2 is the vertical direction when the seat back portion 1B is upright. In this respect, the distance La is preferably closer to the distance h.
The distance h may be, for example, La ≧ h / 2. More preferably, La ≧ 3h / 5.

In this example, the support position P1 and the support position P2 are at the same position in the X direction.
The weight 8d1 is formed of, for example, an iron plate. Assuming that the mass of the weight 8d1 is m1a and the number of stacked sheets is n, the mass m1 of the weight body 8d2 is m1a × n. The mass m1 can be easily adjusted using the mass m1a as an adjustment unit by changing the number n of the weights 8d1 to be stacked.
A sufficiently large gap is provided between the weight 8d2 and the base plate 8a so that the weight 8d2 does not hit the base plate 8a when the weight 8d2 swings, and the spring constants of the coil springs 8c1 to 8c4 are adjusted.

The dynamic damper 8 is symmetric with respect to the center line CL8 in FIG.
Further, the spring constants of the four coil springs 8c1 to 8c4 are set to be two different spring constants.
That is, the dynamic damper 8 is one in which one weight body 8d2 is supported by two types of elastic support units 91 and elastic support units 92 having different spring constants.
Specifically, the spring constants of the coil spring 8c1 and the coil spring 8c2 located on the upper side in the seat back portion 1B that is erected are set to the same spring constant k1. Further, the spring constants of the coil spring 8c3 and the coil spring 8c4 on the lower side are set to be equal to each other and different from the spring constant k1.
Accordingly, the elastic support unit 91 includes an elastic support portion 9a and an elastic support portion 9b, and the elastic support unit 92 includes an elastic support portion 9c and an elastic support portion 9d.

For example, the spring constant k1 of the upper coil springs 8c1 and 8c2 is made larger than the spring constant k2 of the lower coil springs 8c3 and 8c4, so that the spring constants k1 are less likely to be deformed than the lower side.
That is, the dynamic damper 8 includes coil springs 8c1 and 8c2 as elastic bodies, and includes an elastic support unit 91 that supports the weight unit 8d at the support position P1 with a spring constant k1. Further, the dynamic damper 8 includes coil springs 8c3 and 8c4 as elastic bodies, and has an elastic support unit 92 that supports the weight unit 8d at the support position P2 with a spring constant k2 different from the spring constant k1. For example, the spring constant k1 is set larger than the spring constant k2.
In other words, the spring constant of the elastic support unit 91 supported at the support position P1 farther than the spring constant k2 of the elastic support unit 92 supported at the support position P2 close to the connecting portion between the seat back frame 5 and the cushion frame 4. Increase k1.
The values of the spring constant k1 and the spring constant k2 are adjusted by changing the specifications of the coil springs 8c1 to 8c4, for example. Specifically, the coil wire diameter, the effective coil diameter, the effective coil winding number, the total coil winding number, and the coil wire material can be adjusted to be different.

The above-described dynamic damper 8 is configured as a so-called two-degree-of-freedom dynamic damper. A basic model of this two-degree-of-freedom dynamic damper is shown in FIG. In FIG. 4, the reference numerals of the members of the dynamic damper 8 corresponding to the members and the like are applied to the reference numerals of the members of the basic model.

The relationship between the mass M and the parameters in the basic model is as follows.
The length (height) in the Z direction of the mass M is h, and the length (width) in the Y direction is w.
The mass of the mass M is m1.
The mass M is supported at the support position P1 by the elastic support unit 91 having the spring constant k1 with respect to the fixed member J, and is supported at the support position P2 by the elastic support unit 92 having the spring constant k2.
The distance in the Z direction from the position of the center of gravity G of the mass M to the support position P1 is L1, and the distance in the Z direction from the position of the center of gravity G to the support position P2 is L2.

Using these parameters, the moment of inertia around the X axis at the center of gravity G is expressed as Ixx, (Equation 1).

When the translational displacement of the center of gravity G in the Y direction is y and the minute rotational displacement around the X axis at the center of gravity G is θ, the balance between the force and the moment in the basic model shown in FIG. Indicated.

The equation of motion of (Expression 3) is derived from (Expression 2).

The eigenvalues λ ₁ and λ ₂ of [m1] ⁻¹ [k] are calculated from (Equation 4) in which (Equation 3) is expressed as a matrix. Freq ₁ and freq ₂ are obtained from the obtained λ ₁ and λ ₂ as the natural frequency freq _n by the angular frequency ω _n = sqrt (λ _n ) (Formula 5).

As is clear from the above, the two natural frequencies freq ₁ and freq ₂ (hereinafter also referred to as f1 and f2) of the dynamic damper 8 are set by parameters m1, Ixx, k1, k2, L1, and L2. .

As described above, the dynamic damper 8 has the natural frequency f1 and the natural frequency f2 while having one weight body 8d2 as a weight.
Accordingly, the shape (width and height) of the weight 8d2, the mass m1, the Z-direction distances L1 and L2 from the position of the center of gravity G to the support positions P1 and P2, and the coil springs 8c1 to 8c4 can be arbitrarily set. Any one of the coil wire diameter, the coil effective diameter, the coil effective winding number, the total coil winding number, and the coil wire material is adjusted and set so that the natural frequency of the dynamic damper 8 is set to two different desired frequencies. One frequency can be determined.

The fact that the dynamic damper 8 has two different natural frequencies will be further described based on the test results.
For the test, the dynamic damper 8 shown in FIG. 2 was manufactured according to the following specifications. In this test, the effective number of turns N1 and the total number of turns N1a of the coils of the coil springs 8c1 and 8c2 are different from the effective number of turns N2 and the total number of turns N2a of the coils of the coil springs 8c3 and 8c4. did.

<Specifications of the produced dynamic damper 8>
Mass m of the weight 8d2: 1.4 kg
External dimensions of the weight 8d2 [X direction (depth d), Y direction (width w), Z direction (height h)]:
30mm, 40mm, 150mm
Coil effective winding number N1: 4
Total number of coil turns N1a: 7
Correction coefficient (N1a / N1): 1.75
Effective number of turns N2 of coil: 7.5
Total number of turns N2a of coil: 10
Correction coefficient (N2a / N2): 1.33
L1: 60 mm
L2: 60 mm
k1: 10.0 N / mm
k2: 4.0 N / mm
In addition, La / h is 0.8 at 120/150.

The dynamic damper 8 manufactured according to this specification was attached to the shaking table in a posture in which the Z direction is vertical, and vibrations in the Y direction were applied by sweeping in a range of a total amplitude of 0.2 mm and a frequency of 10 to 30 Hz.
The three-dimensional displacement of the weight 8d2 is measured by this sweep excitation, and the translational components in the X to Z directions and the respective axes around the X to Z directions are taken from the measurement data as the X to Z axes, respectively. And obtained a rotational component.
FIG. 5A is a graph showing the translation component (mm), and FIG. 5B is a graph showing the rotation component (rad).

As is clear from FIGS. 5A and 5B, in the swept frequency range (10 Hz to 30 Hz), one resonance point is noticeably generated in the excitation direction (Y direction) as a translational component. Recognize. The resonance frequency is about 13 Hz.
On the other hand, as a rotation component, it can be seen that one resonance point is generated around the Y axis and the Z axis. The resonance frequency is about 13 Hz. It can also be seen that two resonance points are remarkably generated around the X axis. The two resonant frequencies are about 13 Hz and about 23 Hz.
These two resonance frequencies agreed well with the values of the natural frequencies freq1 and freq2 obtained by using (Equation 5) from each value of the specification.

As described above, the dynamic damper 8 rotates around the axis about the direction (X direction) orthogonal to the excitation direction (Y direction) and the separation direction (Z direction) of the support positions P1 and P2 of the weight body 8d2. Thus, resonance occurs at two different frequencies.
Similarly, when the excitation direction is the X direction, resonance occurs at two different frequencies in the rotation around the Y axis.
Further, when the excitation direction is the Z direction, the excitation direction and the separation directions of the support positions P1 and P2 coincide with each other, so that resonance at two different frequencies is not remarkable.
That is, the dynamic damper 8 is based on two natural frequencies in the rotation component for vibrations having vibration directions in all directions except for a specific direction in which the excitation direction and the separation direction of the support positions P1 and P2 coincide. Two effective resonance points can be set.
Thereby, the seat 1 provided with the dynamic damper 8 can suppress at least two large vibrations. As a result, the sheet 1 is less likely to vibrate.
Further, since the seat 1 is provided with only one dynamic damper 8, it can be manufactured at a lower cost and with a smaller mass as compared with the case where a plurality of dynamic dampers 8 are provided.
These effects can be similarly obtained when the dynamic damper 8 is provided in a vehicle equipment other than the seat 1.

In addition, the dynamic damper 8 is integrated with a weight body 8d2 by assembling a plurality of weights 8d1 in a separable manner. Therefore, the mass m1 of the weight body 8d2 can be easily increased or decreased by changing the number of weights 8d1. The increase / decrease of the mass m1 can make the adjustment unit finer by reducing the thickness of the weight 8d1, and fine adjustment of the mass m1 of the weight 8d2 is possible.
Thereby, adjustment of the natural frequency of the dynamic damper 8 is very easy.

(Example 2)
A dynamic damper 18 will be described as a second embodiment. FIG. 6 is a perspective view of the dynamic damper 18. Similar to the dynamic damper 8 of the first embodiment, the dynamic damper 18 is also configured as a two-degree-of-freedom dynamic damper.

The dynamic damper 18 includes a base plate 19 as a base portion, a weight unit 20, and an elastic support unit 21 that elastically supports the weight unit 20 with respect to the base plate 19. In this example, the elastic support unit 21 includes four elastic support portions 21a to 21d.

Specifically, the base plate 19 has a rectangular flat plate-like base portion 19a and side walls 19b and 19c bent in the same direction from both edges of the base portion 19a in the Y direction.
At both edges in the Z direction of the base portion 19a, fixing flange portions 19a1 to 19a4 for overhanging, for example, fixing to the cross frames 5e, 5f, etc. of the seat 1 by overhanging bolts and nuts are formed. Yes.
The inner surfaces 19b1 and 19c1 of the side walls 19b and 19c are parallel surfaces facing each other. Racks 22a and 22b are attached to the inner surfaces 19b1 and 19c1 so as to extend in the Z direction, respectively.

The weight unit 20 has a prismatic shape, and is elastically supported by the elastic support portions 21a to 21d with respect to the base plate 19 in a posture in which the Z direction is a longitudinal direction.
Racks 22c and 22d are attached to side surfaces 20a and 20b in the Y direction of the weight unit 20, respectively. The rack 22c faces the rack 22a, and the rack 22d faces the rack 22b.

As with the weight unit 8d of the first embodiment, the weight unit 20 may be formed as an integral prismatic shape by overlapping a plurality of rectangular plate weights in a separable manner.

The elastic support portions 21a to 21d are the same assembly unit member, and here, different symbols are attached so that the respective arrangement positions can be grasped. Hereinafter, the structure of the elastic support portion 21a will be described as a representative.

FIG. 7 is a three-side view of the elastic support portion 21a. 7A corresponds to a front view seen from the front side in the X direction in FIG. 6, FIG. 7B corresponds to a top view seen from the upper side in the Z direction in FIG. 6, and FIG. This corresponds to a right side view seen from the right side in the Y direction in FIG.

The elastic support portion 21a includes an elastic member 23 formed in a quadrangular prism shape, and a pair of engagement portions 24a and 24a that fix and support both left and right end portions of the elastic member 23.
The elastic member 23 is formed of an elastic material (for example, rubber), and has flange portions 23a and 23a protruding in the Z direction at both ends in the Y direction.

The meshing portion 24a includes an L-shaped plate 24a1 extending in the YZ plane direction, a pinion 24a2 supported so as to be rotatable about an axis CLa extending in the X direction with respect to the plate 24a1, and an allowance for rotation of the pinion 24a2. And a ratchet portion 24a3 for selectively performing the regulation.
The ratchet portion 24a3 is orthogonal to the axis CLb from the claw portion 24a4 and the claw portion 24a4 so that the claw portion 24a4 is rotated by a finger or the like so as to be rotatable about the axis CLb extending in the X direction with respect to the plate 24a1. And a lever 24a5 extending in the direction.

By rotating the lever 24a5 about the axis CLb (arrow Da), the claw portion 24a4 is engaged with the teeth of the pinion 24a2 to restrict the rotation of the pinion 24a2, and the pinion 24a2 is rotated away from the teeth. Can be selectively positioned at an allowable position that allows
The claw portion 24a4 is normally urged so as to be in the restricted position by a spring member (not shown). The claw portion 24a4 is shown in the restricting position in FIG. 7, and is shown in the allowable position in FIG. 6 for convenience.

The plate 24a1 has a holding portion 24a6 that extends in a strip shape in the Z direction in the unfolded state. The holding portion 24 a 6 is bent so as to be wound around the elastic member 23 by pressing, and further crimped, whereby the meshing portion 24 a is attached to the end portion of the elastic member 23.
Thereby, the two meshing parts 24a are respectively attached to both end parts of the elastic member 23. The two engaging portions 24a are attached to the elastic member 23 so that the extending directions of the lever 24a5 are opposite to each other in the Z direction.

As shown in FIG. 6, the elastic support portions 21 a and 21 d are attached between the side wall 19 b and the weight unit 20 in a posture extending in the Y direction. More specifically, the pinions 24a2 of the two meshing portions 24a mesh with the rack 22a and the rack 22c, respectively, and the claw portions 24a4 are disposed at the restriction positions.
That is, the elastic member 23 has an elastic characteristic in which the amount of bending caused by the weight of the weight unit 20 is so small that the pinion 24a2 and the rack 22a or the rack 22c are not disengaged.

The elastic support portion 21a can move in the Z direction by rotating the two pinions 24a2 while meshing with the racks 22a and 22c by setting the two claw portions 24a4 to the allowable position.
Then, the elastic support portion 21a is positioned and fixed by setting the two claw portions 24a4 to the restricted positions at the desired position in the Z direction.
That is, the dynamic damper 18 includes a support position movement adjustment mechanism TK that can move and adjust the support position P11a in the Z direction by moving the elastic support portion 21a in the Z direction and restricting movement at an arbitrary position.
The support position movement adjusting mechanism TK includes racks 22a and 22c arranged opposite to the weight unit 20 and the base plate 19, and two meshing portions 24a having pinions 24a2 meshing with the racks 22a and 22c. Is done.
This support position movement adjusting mechanism TK is also provided for the elastic support portions 21b to 21d so that the support positions P11b to P11d, which are positions for supporting the weight unit 20, can be adjusted in the Z direction.

As described above, the support position movement adjusting mechanism TK allows the elastic support portions 21a to 21d to move independently in the Z direction between the base plate 19 and the weight unit 20, and can be positioned and fixed at a desired position. It has become. This means that the values of L1 and L2 in the basic model shown in FIG. 4 can be set arbitrarily.
Thus, the dynamic damper 18 arbitrarily adjusts the distances in the Z direction between the support positions P11a to P11d of the weight unit 20 and the center of gravity G by arbitrarily determining the positions in the Z direction of the elastic support portions 21a to 21d. The two natural frequencies f1 and f2 can be set to arbitrary values.

The dynamic damper 18 can adjust the spring constant with the elasticity of the elastic member 23 included in each of the elastic support portions 21a to 21d being different to obtain at least two natural frequencies.
For example, the elastic member 23 is formed of rubber, and the elastic members 23 of the elastic support portions 21a and 21b are made harder than the elastic members 23 of the elastic support portions 21c and 21d. Thereby, the spring constant of the elastic support system combining the elastic support portion 21a and the elastic support portion 21b can be made larger than the spring constant of the elastic support system combining the elastic support portion 21c and the elastic support portion 21d. The two natural frequencies can be adjusted and set.

Strictly speaking, a constant spring constant cannot be obtained for rubber, but a substantially constant spring constant can be set under the limited condition of the operation of the dynamic damper 18.

Even when the spring constants of the four elastic members 23 are the same, at least two natural frequencies can be obtained by independently adjusting the fixed positions in the Z direction of the elastic support portions 21a to 21d.
For example, the fixing positions of the elastic support portions 21a and 21b are set closer to the center of gravity G in the Z direction than the fixing positions of the elastic support portions 21c and 21d.
As a result, the spring constant of the elastic support system that combines the elastic support portion 21a and the elastic support portion 21b becomes larger than the spring constant of the elastic support system that combines the elastic support portion 21c and the elastic support portion 21d. Two natural frequencies can be adjusted and set.
When the dynamic damper 18 includes a plurality of elastic support portions 21a to 21d, it does not have to be able to adjust and set all the support positions in the Z direction as described above. It is only necessary that the support position of the weight unit 20 can be adjusted with respect to at least one elastic support portion.

Similar to the dynamic damper 8, the dynamic damper 18 is particularly effective in damping vibration in the Y direction.
Therefore, the dynamic damper 18 may be attached to the vehicle seat in the same posture as the dynamic damper 8.
FIG. 8 is a perspective view showing an example in which the dynamic damper 18 is attached to a frame body 52 of a seat 51 that is a vehicle seat. Specifically, the dynamic damper 18 is provided in at least one of a portion serving as a seat back and a portion serving as a seat cushion. Here, the example which has the dynamic damper 18 in both the site | part used as a seat back and the site | part used as a seat cushion is demonstrated.

As shown in FIG. 8, the frame body 52 includes a seat back frame 53 serving as a skeleton of a seat back serving as a backrest, and a cushion frame 54 serving as a skeleton of a seat cushion to be seated.
The seat back frame 53 includes cross frames 53a and 53b extending in the Y direction. The dynamic damper 18 is attached to the seat back frame 53 by fixing the base plate 19 to the cross frames 53a and 53b with bolts and nuts.
The cushion frame 54 has lower cross frames 54a and 54b extending in the Y direction. The dynamic damper 18 is attached to the cushion frame 54 by fixing the base plate 19 to the lower cross frames 54a and 54b with bolts and nuts.

The dynamic damper 18 is attached to the seat back frame 53 and the cushion frame 54 so that the elastic support portions 21a to 21d extend in the Y direction.
The dynamic damper 8 may be attached to the cushion frame 54 instead of the dynamic damper 18.

The present invention is not limited to the embodiment described above, and various modifications can be made without departing from the gist of the present invention.

In the seats 1, 51, the position where the dynamic dampers 8, 18 are attached is not limited to being the center in the width direction of the frame bodies 2, 52. The position may be biased to either side in the width direction.
The frame configuration of the seat back frames 5 and 53 that support the dynamic dampers 8 and 18 is not limited. The dynamic dampers 8 and 18 may be supported by the seat back frames 5 and 53 or the cushion frame 54.

The shape of the weight 8d1 formed by combining a plurality of weights 8d2 is free and is not limited to a plate shape.
In the seat 1, the spring constant k1 and the spring constant k2 of the dynamic damper 8 are not limited to increasing the upward side in the standing posture of the seat back portion 1B. The lower side may be enlarged. From the viewpoint of stable support of the weight 8d2, it is preferable to enlarge the upper side. The same applies to the dynamic damper 18.
Further, in the above-described embodiment, the weight units 8d and 20 are supported at four points via the four elastic support portions 9a to 9d and 21a to 21d, but via two or three elastic support portions. The weight units 8d and 20 may be supported at two or three points. However, it is preferable that at least one of the plurality of elastic support portions has a spring constant different from that of the other elastic support portions.

In the dynamic damper 8, the elastic support units 91 and 92 that support the weight unit 8d and have different spring constants are not limited to two, and may be three or more. The example in which the elastic support units 91 and 92 support both sides in the width direction of the weight unit 8d at each of the support positions P1 and P2 has been described, but one side in the width direction of the weight unit 8d is supported at each of the support positions P1 and P2. You may do. Although the coil springs 8c1 to 8c4 have been described as the elastic members for supporting the weight body 8d2, the elastic members are not limited to the coil springs, and known elastic members other than the coil springs can be used.
For example, a wave washer or a disc spring may be used. When a wave washer or a disc spring is used, it is possible to suppress vibration at a higher frequency than when a coil spring is used.

The dynamic dampers 8 and 18 of the first and second embodiments may be provided in vehicle equipment other than the vehicle seat.
Vehicle equipment other than seats includes armrests, electrical equipment such as image display devices and amplifiers, imaging devices, and batteries.
FIG. 9 shows an example in which the dynamic damper 18 is attached to a battery 61 that is an accessory of the vehicle 60 (automobile in this example).
The dynamic damper 18 is attached in a posture in which the extending direction of the elastic support portions 21 a, 21 b, 21 c, and 21 d coincides with the vibration direction of the vibration to be damped in the battery 61.
In the example shown in FIG. 9, the extending direction of the elastic support portions 21 a to 21 d is the width direction of the vehicle 60.

The vehicle is not limited to an automobile, but may be a moving body that includes a structure having a seat, such as an aircraft, a ship, and a railroad, and moves while an occupant is seated on the seat.

The present invention can be used for equipment such as a seat and a battery mounted on a vehicle (automobile, aircraft, ship, railway vehicle, etc.) that moves an occupant in a seated state.

Claims (6)

1. A base part;
   A weight unit;
   A first elastic support unit that elastically supports the weight unit at a first support position with a first spring constant with respect to the base portion;
   The weight unit is elastically supported with respect to the base portion at a second support position separated from the first support position in a first direction by a second spring constant different from the first spring constant. Two elastic support units;
   Dynamic damper characterized by comprising.
2. A base part;
   A weight unit;
   A first elastic support unit that elastically supports the weight unit at a first support position with respect to the base portion;
   A second elastic support unit that elastically supports the weight unit at a second support position separated from the first support position in a first direction with respect to the base portion;
   A support position movement adjustment mechanism that enables movement of at least the first support position in the first direction;
   Dynamic damper characterized by comprising.
3. The support position movement adjustment mechanism is
   A base portion side rack provided in the base portion and extending in the first direction;
   A weight unit side rack provided in the weight unit and extending in the first direction;
   A first pinion that engages with the base unit side rack, a second pinion that meshes with the weight unit side rack, and a restriction on rotation of the first pinion, provided in the first elastic support unit; A first ratchet portion that selectively performs allowance, and a second ratchet portion that selectively restricts and permits rotation of the second pinion;
   The dynamic damper according to claim 2, comprising:
4. The distance in the first direction between the gravity center position of the weight unit and the first support position, and the distance in the first direction between the gravity center position and the second support position are: The dynamic damper according to claim 3, wherein rotation of the first pinion and the second pinion is restricted in different states.
5. A vehicle seat that has a seat back frame and a cushion frame and is mounted on a vehicle,
   The dynamic damper according to any one of claims 1 to 4, wherein the dynamic damper according to any one of claims 1 to 4 is attached to at least one of the seat back frame and the cushion frame so that the first direction is a direction perpendicular to the width direction of the vehicle seat. A vehicle seat characterized by being made.
6. Vehicle equipment to be mounted on a vehicle,
   A vehicle equipment comprising the dynamic damper according to any one of claims 1 to 4.

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