JP2016123065A - Speaker stand for placing speaker box thereon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a speaker stand of which the entire center of gravity is set to a speaker unit of a speaker box and which is supported by a line contact type support and suppresses distortion generated from the speaker box by operation of a rotation moment, the speaker stand relating to vibration braking of a speaker installed on a bottom of the speaker box.SOLUTION: In the speaker stand for placing the speaker box thereon, means are devised as follows: (1) providing the support in a lateral width direction relatively to the speaker box for supporting a centroid part of a bottom face of the speaker box substantially in a horizontal attitude; (2) operating the rotation moment on the speaker box and defining a line contact member that is freely rotatable in a longitudinal direction, as the support; and (3) providing elastic members as supports in a front part and a rear part of the support for balancing the speaker box.SELECTED DRAWING: Figure 1

Description

The present invention relates to an apparatus related to vibration braking of a speaker installed at the bottom of a speaker box.

  In the past, distortion caused by vibration of the speaker unit was provided at the bottom of the speaker box with a multi-point or surface contact insulator to provide vibration isolation and braking.

  JP2011-27249

This has the following drawbacks. For an insulator as a multi-point contact, even if the vibration control function of the speaker is too strong or too weak, the sound is poor and it is difficult to select the optimum one. In order to cut off the vibration between the speaker and the floor, the 3-point or 4-point support point contact insulator and the surface contact audio board are fixed so that the bottom of the speaker does not move back and forth and left and right. Generate complex distortions such as torsion and distortion.

With regard to the conventional system, it can be physically explained that the sound changes, but whether or not the sound is improved is largely due to the subjective sensitivity of the listener.
The present invention has been made to solve the above problems. This is not a conventionally used multipoint contact support type, nor is it a surface contact support type. The entire center of gravity is set in the speaker unit portion of the speaker box, which is supported by a line contact support type support, and the distortion generated from the speaker box by the action of the rotational moment is suppressed.

In order to solve the problem, the present invention has devised the following means. A speaker base on which a speaker box is mounted. (1) In order to support the center of gravity of the bottom surface of the speaker box in a substantially horizontal position, a support body is provided in a lateral width direction with respect to the speaker box.
(2) A line contact member that is rotatable in the front-rear direction by a rotational moment acting on the speaker box is defined as the support.
(3) In order to keep the speaker box in equilibrium, elastic members are provided as supports on the front and rear portions of the support.
It is a speaker stand which mounts the speaker box which comprises the above.

Conventionally, when the bottom of the speaker box is fixed, the kinetic energy due to the reaction force generated in the magnet part of the speaker unit is released through the floor surface at the bottom of the speaker box, and the entire weight is received as an external force, so that twist and distortion are caused. Generated and distorted. The vibration due to the reaction of the magnet part takes a complicated path between the frame, then the front baffle, the side face, then the bottom face part, and then the stationary fixed part of the floor, and distortion occurs between them.

According to the present invention, unnecessary vibration generated by the reaction from the magnet portion of the speaker unit is received as a rotational moment centered on the center of gravity, and is released as kinetic energy, which is consumed by the front and rear portions of the speaker box. Since the speaker box is not connected to the floor and no external force is applied and the center of gravity does not change, the speaker box is not subjected to stress that causes distortion, and thus has an effect of suppressing generation of unnecessary vibration. The force of the reaction of the magnet part is captured by the magnet part which is the center of gravity of the total weight of the speaker box. If it demonstrates based on FIG. 2, the position (10) of the center of gravity of the whole is an unstable balance which will move away from a balanced state more and more if a balanced state shifts | deviates by the force F of reaction. Here, when the center of gravity is about to move by the reaction force F, the speaker box (1) is out of balance and tilted obliquely, resulting in movement as a rotational moment. In this way, the rotational moment becomes kinetic energy.
A rotational moment acts around the position of the center of gravity (10) as a whole, and this center of gravity position (10) does not move, so it acts as an internal force F due to the reaction. All this internal force is dissipated and consumed as kinetic energy forward and backward. The speaker box (1) is less susceptible to distortion due to stress. The force F due to this reaction is not connected to the floor as an external force, and there is an effect that the distortion caused by this is small.

According to the present invention, by providing the support (13) in line contact with the position (11) of the center of gravity of the bottom of the speaker box (1), the entire speaker box (1) including the speaker unit (14) and the magnet part is provided. The weight is applied to the position (10) of the entire center of gravity, and the acceleration of vibration is received. If the weight of the speaker unit (14) there is a magnet unit in position (10) of the center of gravity _{M sp,} also the weight of the speaker box and _{M box,} the force _{F 1} of the reaction according to the cone vibration _(M sp _{+ M box} ) × a ---- (1), a: acceleration of the magnet part. On the other hand, the force F of action by the cone diaphragm is represented by F = bm. b: acceleration of cone diaphragm, m: weight of cone diaphragm.
Since the force of action is equal to the force of reaction, the following equation holds.
(M _sp + M _box ) × a = bm −−−− (2), therefore, the acceleration a of the magnet portion is a = mb / (M _sp + M _box ) −−−− (3). This means that the reaction force caused by the vibration of the cone receives the vibration energy with the total weight of the speaker box as the center of gravity. Therefore, there is an effect of suppressing the vibration rather than receiving the reaction force only by the weight of the magnet. Acceleration ratio = cone weight / total weight of the speaker box.
If the weight of the cone is 10 g and the total weight of the speaker box is 20 kg, the acceleration ratio of the magnet portion is a / b = 1/2000, and the vibration damping effect is large.

When the magnet part of the speaker unit (14) vibrates due to the reaction force, it is transmitted to the front baffle (18) through the frame. The vibration energy from the front baffle (18) acts as a rotational moment around the position of the magnet part, and the position of the center of gravity of the magnet part does not change. At this time, the support (13) has a round bar shape. When the front baffle (18) is tilted forward, it rotates counterclockwise, and when it is tilted backward, it rotates clockwise. By this operation, a rotational moment acts around the position (10) of the entire center of gravity. As a result, the vibration caused by the reaction force of the baffle surface (18) at the position of the center of gravity (10) is reversed in phase at the upper and lower portions of this surface, and is in an opposite phase relationship. Offset. The sound pressure released into the space centered on the center of gravity is the negative phase level (16) from the lower baffle surface if the upper baffle surface is the normal phase level (15), and the distorted sound due to the reaction of the magnet part from the baffle surface Is offset in the air and disappears.

The line contact portion of the support body that does not roll, such as a triangular bar attached to the bottom surface portion of the speaker box, has a rotational moment acting here. Referring to FIG. 3 and FIG. 4, FIG. 3 shows a speaker box having its bottom face directly placed on the floor. The baffle surface is vibrated with the floor fixed as an external force by the reaction of the magnet part of the speaker unit. As a result, a strong stress is generated in the speaker box, and a distortion sound is generated by twisting or distortion. If it demonstrates based on FIG. 4, the magnet (6) C point in the position of a gravity center will work a rotational moment centering on a support body (7). When the rotational moment of the magnet unit (6) of the speaker unit is exerted by the reaction of the cone action force, this speed V is V = rw --- (4) r: distance from the fulcrum point d to the point c, w : Angular velocity of rotation.
From equation (4), dV / dt = a is acceleration, dw / dt = f is angular acceleration, and a = fr (5). On the other hand, If = F ₁ r ---- (6). I is a moment of inertia and is I = r ² × (M _sp + M _box ). Here, M _{sp is} the weight of the speaker magnet, M _{box is} the weight of the speaker box, and F _{1 is the} reaction force.
From (6), r ² f × (M _sp + M _box ) = F ₁ r −−− (7)
(5) From the equation, f 1 = a / r, F ₁ = a × (M _sp + M _box ) −−− (8)
The force F of the cone vibration action is F = bm --- (9) b: cone acceleration, m: cone weight, action force F = reaction force F ₁ (8) and (9) more magnet portion acceleration _{a = mb / (M sp +} M box) --- (10), (10) the acceleration a of the magnet unit is much smaller than the acceleration b of the cone from the equation. For example, if the weight of the cone is 10 g, the weight of the speaker unit is 2 kg, and that of the speaker box is 20 kg, a = 10/22000 = 1/200, and the vibration of the magnet part due to the reaction can be suppressed. Furthermore, since the movement by the rotational moment does not connect to the external force, the distortion is not generated as compared with the case where the distortion is placed directly on the floor that becomes the external force.

These are sectional drawings of the side of the present invention. These are operation | movement principle diagrams of this invention. These are the principle diagrams of placing the speaker box directly on the floor. These are the principle diagrams of the present invention. These are the perspective views of the Example of this invention. These are the perspective views which cut and decomposed | disassembled from the cylinder of the line contact support body of this invention.

Hereinafter, an embodiment for carrying out the present invention will be described with reference to FIG. At the position (3) of the center of gravity of the bottom surface portion (2) of the speaker box (1), in the direction parallel to the front surface (9) of the baffle to which the speaker unit (4) is attached, that is, in the width direction of the speaker box (1). A support (5) in line contact is provided. Here, the line contact means that there is a geometrical distance between the bottom surface (2) of the speaker box (1) and the support (5) and between the floor (30) and the support (5). To contact so that it becomes one line.
Moreover, even if it is a point contact, what has the equivalent line contact function arranged in a line linearly is also included. Moreover, even if it is a surface contact, the thing which becomes an unstable balance where it is difficult to take a balance of a bottom face part (2) is included. Here, since the speaker box (1) is line-contact supported by the support (5) at the position of the center of gravity (3), the speaker box (1) is likely to be unbalanced and the front part of the support (5) is in order to be balanced. And an elastic body (7) such as a magnet (6) or sponge is provided at the rear part to achieve equilibrium. Since the support (5) is located at the center of gravity (3), almost the entire weight is applied here, and the elastic body (7) such as the magnet (6) or sponge is supported only to maintain equilibrium. Only a load is applied. It is an auxiliary support. Even if the cone moves, the position of the entire center of gravity of the speaker box (1) does not change due to the reaction, so that a rotational moment acts forward and backward around this, and no lateral change occurs. In order to make this rotational moment work, the support (5) is structured to have a rolling bar-like function. In addition, a triangular structure or the like is used to provide the moment of inertia around the support (5). Some do not roll.

Referring to FIG. 2, when the cone vibrates, the magnet portion at the center of gravity position (10) vibrates due to its reaction. The support (13) in line contact is provided in the lateral width direction at the position of the center of gravity (10) and the position of the center of gravity (11) of the bottom portion.
A rotational moment acts around the position of the center of gravity (10) as a whole, causing the front baffle (18) to vibrate back and forth. Here, the cylindrical support body (13) is used. When the front baffle (18) tilts forward, the rolling rod-like support (13) rotates counterclockwise, while when the front baffle (18) tilts backward, it rotates clockwise. By this movement, a rotational moment acts around the position of the center of gravity (10), that is, the position of the magnet of the speaker unit.
Depending on the reaction force, the position of the center of gravity is not changed, but a rotational motion is made.
The reaction force from the magnet part due to the vibration of the cone is consumed as an internal force and is not connected to the external force, the position of the center of gravity does not change, and the floor surface that causes distortion due to the external force is floating.

FIG. 5 shows a perspective view of a speaker stand according to the present invention. The support (21) and (22) for supporting this are provided on both sides of the line contact support (20). The supports (21) and (22) are fixed to the upper part of the first support member (24).
The elastic body (23) and the same (25) such as sponge are provided on the upper surface portion of the support (21) and (22). This functions to keep the bottom of the speaker box balanced with the line contact support (20) as a fulcrum. An elastic body (26) and the same (27) such as a sponge are provided between the central portion of the line contact support (20) and the side faces of the support (21) and (22) facing the same, Supports the line contact support (20). This is because the line contact support (20) rotates and vibrates around the center of gravity. FIG. 6 is a perspective view of the line contact support (20), in which the center of gravity of a round bar (29) having a radius r is made symmetrical and both sides are cut. This saves space and functions as a round bar-like line contact support within the movable range.

DESCRIPTION OF SYMBOLS 1 Speaker box 2 Bottom part 3 Center of gravity position 4 Speaker unit 5 Line contact support -1
6 Magnet 7 Elastic body 9 Baffle front view 10 Floor surface 19 Center of gravity position c point 22, 23, 24, 25 Elastic body 27, 28 Support body 29 Round bar

Claims (1)

  A speaker stand on which a speaker box is mounted, wherein a rotational moment acts on the speaker box and a support for a line contact member that is rotatable in the front-rear direction is provided, and the center of gravity of the bottom part of the speaker box is set to a substantially horizontal posture. In order to maintain, the speaker stand which mounts the speaker box characterized by providing an elastic member as a support body in the front part and rear part of the said support body.

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