JPH0625637U - damper - Google Patents

Abstract

(57) [Abstract] [Purpose] A damper in which a mass body 3 is connected to one axial side of a hub 1 through an elastic body 2 and the mass body 3 is in operation.
To prevent it from swinging around. [Structure] The second hub 4 is spaced apart on one axial side of the mass body 3, and rails 5 and 6 are provided on the facing surfaces 3a and 4a of the mass body 3 and the second hub 4, respectively. It is assumed to have an arc-shaped portion concentric with the mass body 3 or the second hub 4, and a rolling element 7 rolling along the rails 5 and 6 is sandwiched between the mass body 3 and the second hub 4. The mass body 3 is radially positioned on the second hub 4 via the rolling elements 7.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improved damper. The damper of the present invention is mounted on a rotary drive system of an automobile engine or the like, and is used as a dynamic damper that absorbs and damps vibrations generated on a rotary shaft such as a propeller shaft.

[0002]

[Prior art]

 In the known damper of this type, as shown in FIG. 6, a mass body 23 is connected to one axial side of the hub 21 via an elastic body 22. The hub 21 and the mass body 23 are each made of a predetermined metal, and the elastic body 22 is made of a predetermined rubber. Each part has an annular shape.

[0003]

[Problems to be solved by the device]

 When the low frequency vibration is absorbed and damped by the damper, the spring constant of the elastic body 22 is set to be small in order to set the natural frequency of the damper to be small. Therefore, in this case, since soft rubber is used for the elastic body 22, whirling (eccentricity) of the mass body 23 becomes a problem in a high rotation range.

[0004]

[Means for Solving the Problems]

 In view of the above points, the present invention has been devised in order to solve the problems found in the above-mentioned prior art. In order to achieve this object, as described in claim 1, the shaft of the first hub is The mass body is connected to one side of the mass body via an elastic body, the second hub is spaced apart from the one side of the mass body in the axial direction, and a rail is provided on the facing surface of the mass body and the second hub. The rail has an arc-shaped portion that is concentric with the mass body or the second hub, and includes a rolling element that rolls along the rail between the mass body and the second hub. Provide pa. Further, as described in claim 2, in the damper of claim 1, in addition to the arc-shaped portion, the rail extends obliquely in the inner diameter direction or the outer diameter direction from the end of this arc-shaped portion. Provided is a damper having an oblique portion.

[0005]

[Action]

 In the damper according to the first aspect, the mass body is positioned in the radial direction on the second hub via the rolling element, and this prevents the mass body from swinging around during operation. Further, in the damper according to the second aspect, in addition to the arc-shaped portion, the rail is provided with a slanted portion extending obliquely in the inner diameter direction or the outer diameter direction in series from the end of the arc-shaped portion. Therefore, the spring constant of the damper in the twisting direction (rotational direction) is variable.

[0006]

【Example】

 Next, an embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1, a mass body 3 is connected (vulcanized and bonded) to one axial side (left side in the figure) of the first hub 1 via an elastic body 2, and one axial direction of the mass body 3 is connected. The second hub 4 is spaced apart from the second hub 4 by a predetermined distance. The first hub 1 and the second hub 4 are integrally connected at their inner peripheral ends. Rails 5 and 6 are provided on the facing surfaces 3a and 4a of the mass body 3 and the second hub 4, respectively. The rails 5 and 6 are as follows.

That is, the required number of rails 5 are equally arranged on the facing surface 3 a of the mass body 3, and the same number of rails 6 are equally arranged on the facing surface 4 a of the second hub 4. Rails 5 and rails 6 on the side of the second hub 4 face each other to form a set, and one ball-shaped rolling element 7 is engaged with each set. The rails 5 and 6 are all of the same shape and size, and are provided in the shape of a circular arc groove concentric with the mass body 3 or the second hub 4 as shown in FIG. In the state before the body 2 is not twisted (free state), the displacement in the rotational direction is zero for each set. Further, the elastic body 2 is axially compressed by inserting the rolling element 7 in addition to the elastic body 2 and the mass body 3 between the first hub 1 and the second hub 4.

According to the damper having the above structure, the second hub 4 is fixed to the rotating shaft (not shown) such as the propeller shaft together with the first hub 1, and the rolling element 7 is attached to the second hub 4. Since the mass body 3 is positioned in the radial direction via the, the mass body 3 can be prevented from swinging around during operation. Further, since the rolling element 7 is rotatably engaged with the arcuate rails 5 and 6, the relative rotation angle of the mass body 3 with respect to the second hub 4 is limited, so that the elastic body 2 The amount of twist can be limited to a predetermined amount. That is, the elastic body 2 acts as a stopper in the rotation direction for preventing excessive twisting, and the operating angle of the stopper is θ × 2, where θ is the arc angle of one of the rails 5 and 6.

As shown in each of FIGS. 3 to 5, in addition to the arc-shaped portions 5a and 6a on the rails 5 and 6, respectively, the rails 5 and 6 are obliquely arranged in series from the ends of the arc-shaped portions 5a and 6a. By providing the inclined portions 5b, 6b, 5c, 6c extending in the inner diameter direction or the outer diameter direction, the spring constant in the torsional direction (rotational direction) of the damper can be made variable. The spring constant changes because the rolling resistance of the rolling element 7 is different when rolling the arcuate portions 5a, 6a and when rolling the slanting portions 5b, 6b, 5c, 6c. When the rolling element 7 rolls in the slanted portions 5b, 6b, 5c, 6c, when the relative rotation angle of the mass body 3 with respect to the second hub 4 is large, that is, when the damper is low, When a vibration with a large frequency and a large amplitude is input, such a structure can receive such a vibration with a low frequency and large amplitude with a large spring constant and a natural frequency and effectively damp it.

[0011]

[Effect of device]

 The present invention has the following effects. That is, in the damper according to the first aspect: A) Since the mass body is positioned in the radial direction on the second hub via the rolling element, it is possible to prevent the mass body from swinging around during operation. Therefore, even if soft rubber is used for the elastic body, its durability can be improved without placing an excessive load on the elastic body (setting of the radial direction stopper). B) Since the rolling element is rotatably engaged with the arcuate rail, the relative rotation angle of the mass body with respect to the second hub is limited, and the twist amount of the elastic body is limited to a predetermined amount. can do. Therefore, also by this, the durability can be improved without setting an excessive load on the elastic body (setting of the rotation direction stopper).

Further, in the damper according to the second aspect of the invention, in addition to the arcuate portion of the C) rail, there are oblique portions extending inward in the inner or outer radial direction in series from the end of the arcuate portion. Since the spring constant is provided, the spring constant in the torsional direction (rotational direction) of the damper can be made variable, whereby vibrations of low frequency and large amplitude can be effectively damped.

[Brief description of drawings]

FIG. 1 is a half sectional view of a damper according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing the shape of the rail.

FIG. 3 is an explanatory view showing the shape of the rail.

FIG. 4 is an explanatory view showing the shape of the rail.

FIG. 5 is an explanatory view showing the shape of the rail.

FIG. 6 is a half-cut sectional view of a damper according to a conventional example.

[Explanation of symbols]

 1 first hub 2 elastic body 3 mass body 3a, 4a facing surface 4 second hub 5,6 rails 5a, 6a arc-shaped portion 5b, 6b, 5c, 6c diagonal portion 7 rolling element

Claims (2)

[Scope of utility model registration request] 1. A mass body (3) is connected to one axial side of a first hub (1) through an elastic body (2), and a second hub (one side is connected to one axial side of the mass body (3). 4) are spaced apart,
The facing surface (3) of the mass body (3) and the second hub (4)
a) (4a) is provided with rails (5) and (6), and the rails (5) and (6) have arcuate portions concentric with the mass body (3) or the second hub (4). Then, the mass body (3)
And the rails (5) (6) between the second hub (4) and
A damper with a rolling element (7) rolling along it. 2. The damper according to claim 1, wherein the rails (5) (6) have arc-shaped portions (5a) (6a),
Oblique portions (5) extending inward in the inner diameter direction or the outer diameter direction in series from the ends of the arc-shaped portions (5a) (6a).
b) (6b) (5c) (6c) having a damper.