JP6301153B2 - Support structure for vibrating body - Google Patents

Description

  The present invention relates to a support structure for a vibrating body.

  For example, a shaft member for transmitting the rotational driving force of the engine to the rear differential is connected to the rear differential (rear differential gear) of an automobile. The rear differential is connected to a drive shaft connected to the rear wheel. Accordingly, the rotational driving force of the engine is transmitted to the rear wheel through the shaft member, the rear differential, and the drive shaft.

  When transmitting the rotational driving force, the rear differential or the like may vibrate. This vibration is transmitted to the occupant through the vehicle body frame without any treatment, thereby making the ride comfort of the occupant worse. Therefore, automobiles are often provided with a device for reducing vibration, which is called a dynamic damper.

  As a technique related to a dynamic damper, a technique described in Patent Document 1 is known. Patent Document 1 discloses a rear bracket that extends in the vehicle front-rear direction on the propeller shaft side of the drive shaft, has one end connected to the front differential and the other end fastened to the side member via an elastic bush. A left and right fastening point for elastically supporting the front differential on the side member on the opposite side of the drive shaft with respect to the rear bracket, and a dynamic damper at a position near the fastening point with the side member on the other end of the rear bracket. It is described to wear (see abstract).

JP 2007-196770 A

  In the technique described in Patent Document 1, the dynamic damper is fixed to a rear bracket configured separately by a fastening bolt. Therefore, the number of parts tends to increase. Moreover, since the dynamic damper is configured separately from the bracket, the occupied volume of the dynamic damper and the bracket tends to increase.

  Below the automobile, a certain distance from the ground is secured from the viewpoint of avoiding contact of the device mounted below with the ground. For this reason, when a dynamic damper and a bracket that tend to increase the occupied volume are to be installed below the automobile, their arrangement locations may be restricted from the viewpoint of securing a certain distance from the ground.

  The present invention has been made in view of such problems, and the problem to be solved by the present invention is to reduce the number of parts and save space, and to integrate the bracket and the dynamic damper in various places. An object of the present invention is to provide a support structure for a vibrating body that can be disposed on a surface.

The invention according to claim 1 is a support structure for a vibrating body in which the vibrating body is attached to a supporting body by a bracket attached to the vibrating body, wherein the bracket is made of a plate-like member, and the bracket is provided with a cut. The bracket has a cut portion and a frame portion formed integrally, the cut portion having a weight portion that vibrates when the vibrating body vibrates, and a lever portion that connects the weight portion and the frame portion. The frame portion is attached to the support, the lever portion includes a portion twisted with respect to the surface direction of the frame portion, and the lever portion is the twisted portion. across the, at the site of the frame portion side portion of the weight part side, characterized in that the surface direction different, regarding the support structure of the vibrating body .

According to this, a plate-shaped bracket, a weight part as a dynamic damper, and a lever part can be formed as an integrated object. Therefore, the number of parts can be reduced and the space can be saved, and the integrated bracket and dynamic damper can be arranged in various places.
Moreover, according to this, the vibration produced by rotation of a shaft member can be relieved.

  The invention according to claim 2 is characterized in that the frame portion is also attached to the support, and the frame portion and the support are attached via a vibration isolating member that elastically supports the bracket. To do.

  According to this, the vibration relaxation effect by the dynamic damper can be further enhanced.

Parallel invention according to claim 3, wherein the rotation transmitting member is interposed within the vibrator, wherein the rotation transmission member, the shaft member is coupled to transmit a rotational force, said bracket and said shaft member It is characterized by being arranged in.

  According to this, the integrated body of the bracket and the dynamic damper can be arranged compactly along the shaft member.

  ADVANTAGE OF THE INVENTION According to this invention, while aiming at reduction of a number of parts and space saving, the support structure of the vibrating body which can arrange | position the integrated body of a bracket and a dynamic damper in various places can be provided.

It is a side view of the vehicle body with which the differential front mount bracket of this embodiment was mounted | worn. It is a top view of the vehicle body to which the differential front mount bracket of this embodiment is attached. It is an enlarged view of the differential front mount bracket of this embodiment, (a) is the side view, (b) is the sectional view on the AA line of (a). It is a graph which shows the frequency of the vibration which can be relieved with the differential front mount bracket of this embodiment. It is an enlarged view of another differential front mount bracket of this embodiment, (a) is the side view, (b) is the BB sectional drawing of (a).

  Hereinafter, a form (this embodiment) for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a side view of a vehicle body V to which a differential front mount bracket 100 according to this embodiment is mounted. In FIG. 1, the shape of the vehicle body V is shown using virtual lines.

  The differential front mount bracket 100 is attached to the vehicle floor V1 of the vehicle body V so as to extend in the front-rear direction of the vehicle body V. Specifically, the differential front mount bracket 100 is attached to the rear differential 20 to which the propeller shaft 10 is connected via the differential rear mount bracket 40 behind the vehicle body V. The differential front mount bracket 100 is attached to the vehicle floor V1 (that is, the vehicle body V) via the differential front mount 30 in front of the vehicle body V. The differential front mount 30 is a vibration isolation member that elastically supports the differential front mount bracket 100. Thereby, the vibration propagated from the rear differential 20 or the like to the differential front mount bracket 100 is prevented from propagating to the vehicle body V.

  FIG. 2 is a top view of the vehicle body V to which the differential front mount bracket 100 of the present embodiment is attached. Also in FIG. 2, the shape of the vehicle body V is shown using virtual lines.

  A propeller shaft 10 connected to an engine (not shown) is connected to the rear differential 20 via a joint portion 70. A differential gear (rotation transmission member) (not shown) is interposed in the rear differential 20. In addition, wheels W are connected to the differential gear via drive shafts 50 in the left-right direction of the vehicle body V, respectively.

  Accordingly, when the propeller shaft 10 is rotationally driven, the rotational driving force is transmitted to the wheel W via the rear differential 20 and the drive shaft 50, and the wheel W is rotated. In addition, when a rotational difference occurs between a front wheel and a rear wheel W (not shown), the rotational driving force of the propeller shaft 10 is transmitted to the viscous coupling 60.

  The rear differential 20 is attached to the vehicle floor V <b> 1 via a differential rear mount bracket 40. The differential rear mount bracket 40 is attached to the vehicle floor V <b> 1 by two differential rear mounts 41. The differential rear mount 41 is a vibration isolating member that elastically supports the rear differential 20, thereby preventing vibration of the rear differential 20 from propagating to the vehicle body V.

  3A and 3B are enlarged views of the differential front mount bracket 100 according to the present embodiment, in which FIG. 3A is a side view thereof, and FIG. 3B is a cross-sectional view taken along line AA of FIG. For convenience of illustration, illustration of each member that is visible behind the differential front mount bracket 100 when the differential front mount bracket 100 is attached to the vehicle body V is omitted.

  As shown in FIG. 3A, the differential front mount bracket 100 includes a frame part 110, a lever part 120, and a weight part 130, which are integrally formed. The frame portion of the differential front mount bracket 100 has a U-shaped cross section as shown in FIG. 3B, and the lever portion 120 and the weight portion 130 are surrounded by the frame portion 110.

  Further, as described above, the bolts 111 and 111 for attaching the differential front mount bracket 100 to the rear differential 20 are attached to the rear of the vehicle body V in the frame portion 110. Further, as described above, the differential front mount 30 for attaching the differential front mount bracket 100 to the vehicle floor V1 is formed in front of the vehicle body V in the frame portion 110.

  The frame part 110 is configured by a plate-like member (sheet metal) provided with a cut. That is, by providing a cut in the plate-like member, the frame part 110 is formed integrally with the provided cut. The frame part 110 is formed in a trapezoidal shape in a side view. In addition, a notch portion that integrally includes the lever portion 120 (lever portions 120 a and 120 b, the torsion portion 120) and the weight portion 130 is formed integrally with the frame portion 110 inside the frame portion 110.

  The lever portion 120 includes a lever portion 120a and a lever portion 120b. Between the lever part 120a and the lever part 120b, the torsion part 121 for making these surface directions different is provided. The lever portion 120 a extends in the same plane direction as the frame portion 110. The lever portion 120b extends in a surface direction orthogonal to the surface direction of the lever portion 120a (that is, the surface direction of the frame portion 110) when the lever portion 120a is twisted in the torsion portion 121. is there.

  A weight portion 130 formed by folding a part of the plate-like member is formed at the tip of the lever portion 120b. Therefore, the lever portion 120 connects the weight portion 130 and the frame portion 110. The weight part 130 is formed by folding a plate-like member (not shown) cut so as to have a vertical width as shown in FIG. 3B.

  Moreover, the lever part 120 functions as a plate spring in the vertical and horizontal directions. Specifically, the lever portion 120a of the lever portion 120 can vibrate (bend) in the left-right direction (direction perpendicular to the paper surface of FIG. 3). The lever portion 120b of the lever portion 120 can vibrate (bend) in the vertical direction. The vibration relaxation by the differential front mount bracket 100 using this point will be described below.

  The differential front mount bracket 100 is attached to the rear differential 20 and the vehicle body V as shown in FIGS. In the present embodiment, the differential front mount bracket 100 is attached to be parallel to the propeller shaft 10 as shown in FIG.

  When an engine (not shown) is driven, the propeller shaft 10 connected to the engine also rotates. At this time, as the propeller shaft 10 rotates, vibrations in the vertical and horizontal directions are generated from the rear differential 20 and the like. This vibration is transmitted to the differential front mount bracket 100 attached to the rear differential 20. In the present embodiment, the differential front mount bracket 100 relaxes (suppresses or absorbs) the transmitted vibration. This makes it difficult for vibration to propagate to the occupant in the vehicle body V, and the ride comfort of the occupant is improved.

  FIG. 4 is a graph showing vibration frequencies that can be mitigated by the differential front mount bracket 100 of the present embodiment. The greater the vibration acceleration, the more intense the vibration. The differential front mount bracket 100 of the present embodiment is set so as to be able to mitigate vibrations at frequencies f1 and f2 shown in FIG.

  Here, in the differential mount bracket 100 of the present embodiment, as described above, the lever portion 120a and the lever portion 120b in the direction orthogonal to the lever portion 120a are combined, and these function as a leaf spring. . Therefore, in the differential front mount bracket 100, the resonance frequency is set to two frequencies, the frequency f1 in the horizontal direction and the frequency f2 in the vertical direction.

  Here, the resonance frequency of the notch portion formed of the lever portion 120 and the weight portion 130 depends on the shape of the lever portion 120a (surface orientation, size, weight, etc.) and the shape of the lever portion 120b (surface orientation and size). And weight). For example, in the lever member 120a (see FIG. 3A), the rigidity in the left-right direction (direction perpendicular to the surface) is low. Therefore, the resonance frequency (frequency f1 shown in FIG. 4) in that direction becomes low. On the other hand, the rigidity in the vertical direction (direction parallel to the surface) is high. Therefore, the resonance frequency (frequency f2 shown in FIG. 4) in that direction becomes high.

  Therefore, when the frequency of vibration from the rear differential 20 or the like is low, the plate surfaces of the lever member 120a and the lever member 120b may be oriented in the vibration direction in order to adjust the resonance point to this low frequency. If it is desired to further reduce the frequency, these plate widths can be narrowed to lower the spring constant, these can be lengthened, or they can be made heavy to lower the eigenvalue. On the contrary, when the frequency of vibration is high, it is only necessary to take the opposite of these correspondences. By combining these methods, the differential front mount bracket 100 of the present embodiment can freely deal with frequencies in two directions.

  When changing the spring constant of the lever part 120a or the lever part 120b, change it according to necessity, for example, depending on the inclination or degree of rotation of the arm part 120a or arm part 120b, the degree of torsion at the torsion part 121, etc. Can do. Therefore, by adjusting the lever part 120a, the lever part 120b, the torsion part 121, etc. according to the frequency peak of vibration, the notch part can be vibrated and vibrations in two directions can be alleviated simultaneously and effectively.

  In particular, the frequency of vibration from the rear differential 20 or the like may change as the rotational speed of the propeller shaft 10 changes. Further, the vibration frequency from the rear differential 20 or the like may change due to deterioration of other members over time or the like. Therefore, even in such a case, according to the present embodiment, the vibration can be reduced by performing the adjustment as described above according to the frequency of the vibration.

  Further, as described above, the direction and frequency of the vibration from the rear differential 20 or the like that uses the vibration of the propeller shaft 10 as a vibration source may change. Therefore, conventionally, in order to correspond to resonance points having different frequencies in two directions, two dynamic dampers having different frequencies oscillating in the directions have been provided. However, in the present embodiment, the single differential front mount bracket 100 can cope with different frequencies in two directions. Therefore, since the same member can be used for different frequencies in two directions, the vehicle body V can be reduced in weight, cost, and space can be saved rather than using two dynamic dampers.

  Furthermore, in the differential front mount bracket 100 of this embodiment, by twisting with the torsion part 121 in the middle of the lever part 120, it is possible to deal with both the vibration in the left-right direction and the vibration in the up-down direction independently. Therefore, the lever portions 120a and 120b can be easily finely adjusted according to the direction of vibration, and vibrations in various directions can be reduced with a simple configuration.

  Further, depending on the shape of the vehicle body V, the total length of the differential front mount bracket 100 may be different, or the corresponding frequency and vibration direction may be different depending on the weight of the rear differential 20. However, even in such a case, the vibration corresponding to the vehicle body can be easily and effectively reduced by finely adjusting the lever portion 120a or the lever portion 120a by slightly bending it.

  Further, the mount bracket is attached below the vehicle body V. However, in consideration of the relative position between the ground and the floor V1 of the vehicle body V, the size (height) of a member that can be attached below the vehicle body V is limited. Accordingly, the types of members that can be attached to the lower side of the vehicle body V are substantially limited, and the number of members that can be attached is also limited.

  Therefore, in the present embodiment, the differential front mount bracket 100 performs vibration reduction by performing predetermined processing on the differential front mount bracket 100. For this reason, it is not necessary to separately provide a special member (dynamic damper) for vibration reduction, there is no structural limitation on the vehicle body V, and any vehicle can be mounted satisfactorily.

  In addition to the differential front mount bracket 100 described with reference to FIGS. 1 to 4, the following differential front mount bracket is also suitable as the differential front mount bracket of the present embodiment.

  5A and 5B are enlarged views of another differential front mount bracket 200 of the present embodiment, in which FIG. 5A is a side view thereof, and FIG. 5B is a sectional view taken along line BB of FIG. 5, the same members as those of the differential front mount bracket 100 shown in FIG. 3 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The differential front mount bracket 200 shown in FIG. 5 differs from the differential front mount bracket 100 shown in FIG. 3 in the shape of the lever portion 120. Specifically, in the differential front mount bracket 200, two twisted portions 121 are provided. More specifically, the torsion portions 121 are provided at two locations, one at the boundary between the frame portion 110 and the lever portion 120b and one at the middle of the lever portion 120, respectively. Therefore, unlike the differential front mount bracket 100 shown in FIG. 3, the lever portion 120a bent in the left-right direction is disposed at the front portion of the vehicle body V, and the lever portion 120b bent in the vertical direction is disposed at the rear portion of the vehicle body V. Will be.

  Further, the number of folding stages of the weight section 230 connected to the front arm section 120a is the same as that of the weight section 130 shown in FIG. However, the folding direction is different. Specifically, the weight portion 130 of the differential front mount bracket 100 shown in FIG. 3B is folded so as to be stacked in the vertical direction. However, the weight portion 230 of the differential front mount bracket 200 shown in FIG. 5B is folded so as to be stacked in the left-right direction.

  Here, in the differential front mount bracket 100 shown in FIG. 3, when the vibration in the vertical direction (see FIG. 3A) is reduced, the lever portion 120b is mainly bent. On the other hand, when the vibration of the frequency in the left-right direction (see FIG. 3B) is relieved, the entire lever portion 120 (the total length of the lever portion 120a and the lever portion 120b) is bent. At this time, the lever part 120a is mainly bent. For this reason, the vibration frequency of the weight portion 130 is lower in the left-right direction than in the up-down direction. Therefore, the differential front mount bracket 100 of FIG. 3 is suitable when dealing with a case where the left-right vibration frequency of the differential front mount bracket 100 is lower than the vertical vibration frequency.

  On the other hand, in the differential front mount bracket 200 shown in FIG. 5, when the vibration in the vertical direction (see FIG. 5A) is reduced, the entire lever portion 120 (the total length of the lever portion 120a and the lever portion 120b). Will bend. At this time, the lever part 120b is mainly bent. On the other hand, when the vibration of the frequency of the left-right direction (refer FIG.5 (b)) is relieve | moderated, the lever part 120a will mainly bend. Therefore, the vibration frequency of the weight part 230 is lower than the vibration frequency in the left-right direction. Therefore, the differential front mount bracket 200 of FIG. 5 is suitable when dealing with a case where the vertical vibration frequency of the differential front mount bracket 100 is lower than the horizontal vibration frequency.

  As described above, the differential rear mounting bracket of the present embodiment has been described with reference to a specific embodiment. However, the differential rear mounting bracket of the present embodiment is not limited to the above examples.

  For example, as the shape of the lever portion 120, the length, width and shape of the lever portion 120a and the lever portion 120b, which are variables for changing the above-described spring constant, the position, the twist angle, and the number of the torsion portion 121 are illustrated in the illustrated example. It is not limited at all. Therefore, for example, in the illustrated example, the length of the lever portion 120a and the length of the lever portion 120b are substantially the same, but the length can be appropriately changed in accordance with the frequency of vibration from the rear differential 20 or the like. .

  Further, in the illustrated example, in order to correspond to the vibration in the up-down direction and the vibration in the left-right direction, the torsion portion so that the surface where the lever portion 120a extends and the surface where the lever portion 120b extends are orthogonal to each other. 121 was provided. However, according to the direction of vibration, the degree of torsion at the torsional part 121 and the angle between the surface from which the lever part 120a extends and the surface from which the lever part 120b extends can be changed as appropriate.

  Further, in order to change the spring constant of the lever portion 120, a spring or the like is formed in the space between the lever portion 120a or the lever portion 120b and the frame portion 110 (the vertical space existing between them in FIG. 3). The elastic member may be arranged. Also by this, the spring constant of the lever part 120a and the lever part 120b can be made a desired thing.

  Further, the weight portion 130 is formed by folding an integrally formed plate-like member in the illustrated example, but the weight portion 130 may be adjusted with a bolt that can be tightened up and down, for example. Good.

  Further, in the above example, the rear differential 20 is mainly cited as a vibration generation source. However, the differential mount bracket according to the present embodiment can satisfactorily mitigate against vibration from a member other than the rear differential 20. Therefore, this embodiment is applicable according to the generation source of vibration.

  Further, although the differential rear mount bracket attached to the vehicle body V has been described as an example of the vibration body support structure of the present embodiment, it is not limited to the differential rear mount bracket as long as it is a bracket attached to the vibration body. In addition, “attaching” here includes a mode in which a bracket is directly attached to a vibrating body (without any member), and indirectly to the vibrating body (some member). Via) brackets are included. The form in which the bracket is attached to the support is the same. Further, the support is not limited to the vehicle body V, and can be supported by any support. Therefore, the vibrating body support structure of the present embodiment is not necessarily applied to a vehicle such as an automobile, and can be applied to other uses.

  Further, the shape of the bracket is not limited to the shape shown in FIG. 3, for example. Therefore, the design of the shape of the bracket may be changed as appropriate according to the mounting position of the bracket.

  Further, as shown in FIG. 2, the differential front mount bracket 100 is attached so as to be parallel to the propeller shaft 10, and the positional relationship thereof is parallel (including substantially parallel, the same applies hereinafter). Is preferred, but not necessarily parallel.

  Furthermore, although it is preferable that the arm part 120 includes the twisted part 121, the twisted part 121 is not an essential member. Therefore, it is possible not to provide the torsion part 121 according to the frequency of vibration to be reduced.

10 Propeller shaft (shaft member)
20 Rear differential (vibrating body)
30 differential front mount (anti-vibration member)
40 differential rear mount bracket 41 differential rear mount (vibration isolation member)
50 Drive shaft (shaft member)
60 Viscous coupling 70 Joint 100 Differential front mount bracket (bracket)
110 Frame portion 120, 120a, 120b Lever portion (cut portion)
121 Twist part (cut part, lever part)
130 Weight part (cut part)
230 Weight part (cut part)
V body (support)
V1 Body floor (support)
W wheel

Claims (4)

A support structure for a vibrating body, wherein the vibrating body is attached to a support body by a bracket attached to the vibrating body,
The bracket is made of a plate-shaped member,
By providing an incision in the bracket, the bracket is integrally formed with an incision part and a frame part,
The cut portion integrally includes a weight portion that vibrates when the vibrating body vibrates, and a lever portion that connects the weight portion and the frame portion,
The frame portion is attached to the vibrating body;
The lever portion includes a portion twisted with respect to the surface direction of the frame portion ,
The lever support structure according to claim 1, wherein the lever portion has a surface direction different between the weight portion side portion and the frame portion side portion with the twisted portion interposed therebetween . The frame part is also attached to the support,
2. The support structure for a vibrating body according to claim 1, wherein the frame portion and the support body are attached via a vibration isolating member that elastically supports the bracket. Wherein the vibrating body is interposed the rotation transmitting member therein, the the rotation transmission member, the shaft member is coupled to transmit a rotational force,
The support structure for a vibrating body according to claim 1, wherein the bracket is disposed in parallel with the shaft member. 4. The support structure for a vibrating body according to claim 1, wherein the lever portion extends in parallel with the frame portion. 5.

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