JP7374754B2 - Vibration isolator - Google Patents

Description

The present invention relates to a vibration isolator.

In a conventional vibration isolator, an inner shaft member is inserted through a mounting hole formed in a support part of a vehicle body, and two split cylindrical rubber parts are inserted into the inner shaft member so as to face each other in the axial direction. There is a rubber cushion for tanks (see, for example, Patent Document 1). According to this vibration isolator, the axial vibration isolator provided on the split cylindrical rubber exhibits a damping effect against vertical vibration, while the axial vibration isolator provided on the split cylindrical rubber exhibits a damping effect against vertical vibration. By being disposed between the axially facing surfaces of the inner shaft member and the support portion, it is possible to exhibit a damping effect against axially perpendicular vibrations.

Japanese Patent Application Publication No. 2012-97770

However, in the above-mentioned conventional vibration isolator, the axis-perpendicular vibration isolating rubber portion is arranged between the inner shaft member and the support portion. Therefore, in the conventional vibration isolating device, there is room for improvement in the durability of the split cylindrical rubber.

An object of the present invention is to provide a vibration isolator with improved durability.

A vibration isolator according to the present invention includes an upper mount elastic body and a lower mount elastic body that sandwich a frame of a vehicle, and a vibration damping device that penetrates through an opening formed in the frame and connects to the upper mount elastic body and the lower mount elastic body. It includes an extending shaft member and an elastic member disposed on the outer peripheral surface of the shaft member. According to the present invention, a vibration isolating device with improved durability can be obtained.

Further, in the vibration isolating device according to the present invention, it is preferable that an axis-perpendicular gap is formed between the elastic member and the opening when the vibration isolating device is attached to the vehicle. In this case, the vibration isolating device can easily tune the spring stiffness in the direction perpendicular to the axis to a desired spring stiffness.

Furthermore, in the vibration isolator according to the present invention, the dimension of the gap in the axial direction may vary along the circumferential direction. In this case, a vibration isolating device is obtained in which the spring stiffness in the direction perpendicular to the axis is easily tuned to a desired spring stiffness.

Further, in the vibration isolating device according to the present invention, the outer shape of the elastic member may be an uneven shape along the circumferential direction when viewed in the axial direction. In this case, a vibration isolating device is obtained in which the spring stiffness in the direction perpendicular to the axis is easily tuned to a desired spring stiffness.

Further, in the vibration isolating device according to the present invention, the outer shape of the elastic member may be an elongated shape having a long axis and a short axis when viewed in the axial direction. In this case, a vibration isolating device is obtained in which the spring stiffness in the direction perpendicular to the axis is easily tuned to a desired spring stiffness.

Further, in the vibration isolating device according to the present invention, the vibration isolating device further includes the frame, and the opening portion is formed by an inner peripheral surface of a cylindrical portion provided in the frame, and the opening portion is formed by an inner circumferential surface of a cylindrical portion provided in the frame. It is preferable that a distal end portion of the inner circumferential surface of the cylindrical portion expands outward in the axial direction toward the distal end of the cylindrical portion. In this case, durability is further improved.

Moreover, in the vibration isolator according to the present invention, it is preferable that the shaft member is press-fitted into the elastic member. In this case, the elastic member can be firmly fixed to the shaft member.

Moreover, it is preferable that the vibration isolator according to the present invention is a cab mount. In this case, the cab mount will be more durable.

According to the present invention, it is possible to provide a vibration isolating device with improved durability.

1 is a cross-sectional view schematically showing a vibration isolator according to an embodiment of the present invention in a cross section including a central axis of the vibration isolator. FIG. 2 is a half-sectional view showing an enlarged main part of the vibration isolator shown in FIG. 1; 3 is a cross-sectional view taken along the line AA in FIG. 2. FIG. 3 is a sectional view corresponding to the AA section in FIG. 2, showing another example of the elastic member constituting the vibration isolator in FIG. 1. FIG. 3 is a sectional view corresponding to the AA section in FIG. 2, showing still another example of the elastic member constituting the vibration isolator in FIG. 1. FIG. FIG. 2 is an enlarged sectional view showing another example of the opening of the frame constituting the vibration isolator of FIG. 1, corresponding to region R in FIG. 1;

Hereinafter, vibration isolating devices according to various embodiments of the present invention will be described with reference to the drawings.

The vibration isolator 1 according to this embodiment is a cab mount that connects the cab (body) of a vehicle to the frame (chassis) of the vehicle. In the following description of each embodiment, substantially the same parts will be designated by the same reference numerals, and the description thereof will be omitted as appropriate.

Furthermore, in the following description, the axial direction refers to the direction in which the central axis O (hereinafter also referred to as "axis O") of the vibration isolator extends. In this embodiment, the axis O extends parallel to the vertical direction. In this embodiment, the upper side in the axial direction refers to the upper side in the vertical direction (also simply referred to as "upper side"). Furthermore, in the present embodiment, the lower side in the axial direction refers to the lower side in the vertical direction (also simply referred to as "lower side"). Furthermore, the axial direction refers to a direction perpendicular to the axial direction, and includes the radial direction. In addition, in this embodiment, the axially perpendicularly outer side refers to the side far from the axis O (also referred to as the "radially outer side"). In this embodiment, the inner side in the axial direction refers to the side closer to the axis O (also referred to as the "radial inner side"). Furthermore, in this embodiment, the circumferential direction refers to a direction along the circumference of the axis when viewed in the axial direction.

FIG. 1 is a diagram showing a vibration isolator 1 in an axial cross section. Here, the axial cross section is a cross section that includes the axis O.

The vibration isolator 1 includes an upper mount elastic body 3 and a lower mount elastic body 4 that sandwich a frame 2 of the vehicle.

In this embodiment, the upper mount elastic body 3 is arranged above the frame 2. In this embodiment, the upper mount elastic body 3 is made of rubber. However, the upper mount elastic body 3 is not limited to rubber. For example, the upper mount elastic body 3 can be formed of a material having rubber elasticity. In this embodiment, the cab 7 is arranged above the upper mount elastic body 3. In this embodiment, the cab 7 is attached to the upper mount elastic body 3 via the upper plate 8. In this embodiment, the upper plate 8 is composed of two upper plates, a first upper plate 8a and a second upper plate 8b. However, the upper plate 8 can be composed of at least one upper plate.

Further, in this embodiment, the lower mount elastic body 4 is arranged below the frame 2. In this embodiment, the lower mount elastic body 4 is made of rubber. However, the lower mount elastic body 4 is not limited to rubber. For example, the lower mount elastic body 4 can be formed of a material having rubber elasticity. In this embodiment, a lower plate 9 is attached below the lower mount elastic body 4. In this embodiment, the lower plate 9 is composed of one lower plate. However, the lower plate 9 may be composed of at least one lower plate.

In this embodiment, the lower part of the upper mount elastic body 3 is arranged on the inner surface of the recess 2a of the frame 2. Further, in this embodiment, the lower mount elastic body 4 is arranged on the lower surface of the recess 2a. Furthermore, in this embodiment, the frame 2 is formed with a flat portion 2b that surrounds the recessed portion 2a in the axial direction.

The vibration isolator 1 also includes a shaft member 5 that passes through an opening A formed in the frame 2 and extends to the upper mount elastic body 3 and the lower mount elastic body 4.

In this embodiment, the shaft member 5 passes through the upper mount elastic body 3 and the lower mount elastic body 4 together with the frame 2 . Moreover, in this embodiment, the shaft member 5 is a hollow shaft member (cylindrical member). In this embodiment, the central axis of the cylindrical portion 2c coincides with the central axis O of the vibration isolator 1. Further, in this embodiment, the shaft member 5 includes a bolt B and a nut N. The bolt B passes through the cab 7 and the upper plate 8 to the lower plate 9. A nut N is screwed onto the tip of the bolt B. The upper mount elastic body 3 and the lower mount elastic body 4 approach each other in the axial direction by screwing the nut N onto the bolt B. Thereby, the upper mount elastic body 3 and the lower mount elastic body 4 are each attached to the frame 2 in a pre-compressed state. In this embodiment, washers W are interposed between the bolt B and the cab 7 and between the nut N and the lower plate 9, respectively. In addition, in this embodiment, the bolt B is passed through from the upper side to the lower side and the nut N is attached, but in consideration of ease of assembly to the vehicle, etc., the bolt B is passed through from the lower side to the upper side. It is also possible to attach a nut N.

Further, the vibration isolator 1 includes an elastic member 6 disposed on the outer peripheral surface 5f of the shaft member 5.

In this embodiment, the elastic member 6 covers the entire outer peripheral surface 5f of the shaft member 5. Further, in this embodiment, the elastic member 6 covers the outer circumferential surface 5f of the shaft member 5 along the axial direction. That is, in this embodiment, the elastic member 6 is formed of a cylindrical member. In particular, in this embodiment, the elastic member 6 covers the outer peripheral surface 5f of the shaft member 5 along the axial direction over the entire length of the shaft member 5. The elastic member 6 can also be arranged at a predetermined position in the axial direction with respect to the shaft member 5 in consideration of vibrations after being assembled into a vehicle. On the other hand, if the shaft member 5 is covered with the elastic member 6 over the entire length of the shaft member 5 as in the present embodiment, the workability when assembling it into a vehicle is improved.

In this embodiment, the elastic member 6 is made of rubber. However, the elastic member 6 is not limited to rubber. For example, the elastic member 6 can be formed of a material having rubber elasticity. Further, according to the present invention, the elastic member 6 can be formed of resin or elastomer other than rubber. Examples of such materials include TPE (thermoplastic elastomer).

Referring to FIG. 1, in this embodiment, the frame 2 is provided with a cylindrical portion 2c. In this embodiment, the cylindrical portion 2c is provided in the recess 2a of the frame 2. In this embodiment, the opening A formed in the frame 2 is formed by the inner circumferential surface 2f of the cylindrical portion 2c. In this embodiment, the cylindrical portion 2c of the frame 2 protrudes downward in the axial direction from the recessed portion 2a of the frame 2. However, according to the present invention, the cylindrical portion 2c of the frame 2 can also be made to protrude upward in the axial direction from the recessed portion 2a of the frame 2. Further, according to the present invention, the opening A formed in the frame 2 may be only a through hole formed in the frame 2 without providing the cylindrical portion 2c. Note that in this embodiment, the central axis of the cylindrical portion 2c coincides with the central axis O of the vibration isolator 1.

According to the vibration isolator 1 according to the present embodiment, the elastic member 6 is arranged on the outer peripheral surface 5f of the shaft member 5, so that the shaft member 5 can directly contact the cylindrical portion 2c provided on the frame 2. There is no. That is, according to the present embodiment, the elastic member 6 disposed on the outer peripheral surface 5f of the shaft member 5 can prevent the frame 2 and the shaft member 5 from coming into contact. Therefore, according to the present embodiment, the displacement of the shaft member 5 and the frame 2 in the axial direction can be restricted by the elastic member 6.

On the other hand, in the conventional vibration isolator, an axially perpendicular vibration isolating elastic body part (rubber part) is provided on at least one of the upper mount elastic body 3 and the lower mount elastic body 4, and the axially perpendicular vibration isolating elastic body part is attached to the frame. It is arranged between the opening A formed in 2 and the shaft member 5. In this case, there is a concern that the axis-perpendicular vibration-proof elastic body portion may crack or the like due to contact with the frame 2 and the shaft member 5.

On the other hand, according to the vibration isolating device 1 according to the present embodiment, the elastic member 6 disposed on the outer peripheral surface 5f of the shaft member 5 serves as a buffer member. Therefore, unlike conventional vibration isolators, there is no need to extend the elastic body portion axially downward from the upper mount elastic body 3 and arrange it in the opening A formed in the frame 2. Similarly, by extending the elastic body portion upward in the axial direction from the lower mount elastic body 4, there is no need to arrange it in the opening A formed in the frame 2. That is, according to the present embodiment, there is no need for an axially perpendicular vibration-proofing elastic body part in both the upper mount elastic body 3 and the lower mount elastic body 4 to prevent contact between the frame 2 and the shaft member 5. Become. Therefore, according to this embodiment, the upper mount elastic body 3 and the lower mount elastic body The durability of the body 4 is improved. Therefore, according to this embodiment, the vibration isolator 1 has improved durability.

Further, in this embodiment, the elastic member 6 is formed separately from the upper mount elastic body 3 and the lower mount elastic body 4. Therefore, according to the present embodiment, various functions can be added to the elastic member 6 without affecting the vibration damping performance of the upper mount elastic body 3 and the lower mount elastic body 4.

According to this embodiment, since the elastic member 6 is separate, the shape, hardness, etc. of the elastic member 6 can be appropriately set independently of the upper mount elastic body 3 and the lower mount elastic body 4. Thereby, the elastic member 6 can control the axis-perpendicular displacement of the shaft member 5 and the frame 2 and the load deflection characteristics independently of the upper mount elastic body 3 and the lower mount elastic body 4.

Furthermore, in this embodiment, the elastic member 6 is made of rubber. Therefore, the generation of abnormal noise that may occur when the elastic member 6 and the frame 2 come into contact can be further suppressed. According to this embodiment, since the elastic member 6 is a separate member, the elastic member 6 can be formed of self-lubricating rubber independently of the upper mount elastic body 3 and the lower mount elastic body 4. Thereby, the elastic member 6 can further suppress the generation of abnormal noise that may occur when the elastic member 6 and the frame 2 come into contact.

Further, according to the present embodiment, by arranging the elastic member 6 on the outer peripheral surface 5f of the shaft member 5, surface treatment (for example, plating treatment) on the shaft member 5 can be omitted. Thereby, according to this embodiment, the production cost of the vibration isolator 1 can be suppressed.

Furthermore, with reference to FIG. 2, the vibration isolator 1 according to the present embodiment has an axially perpendicular direction between an opening A formed in the frame 2 and the elastic member 6 when it is attached to a vehicle. A gap C is formed. In this case, by adjusting the axis-perpendicular dimension dc of the gap C along the circumferential direction, the spring rigidity of the entire vibration isolator 1 in the axis-perpendicular direction can be adjusted by changing the contact timing between the elastic member 6 and the frame 2. , can be varied along the circumferential direction. Therefore, in this case, by adjusting the gap C, the vibration isolating device can easily tune the spring stiffness in the axial direction to a desired spring stiffness. Further, in this case, the shaft member 5 on which the elastic member 6 is arranged can be easily assembled by passing it through the opening A formed in the frame 2. However, according to the present invention, the gap C in the axial direction between the elastic member 6 and the opening A can be set to C≦0. That is, according to the present invention, the elastic member 6 and the opening A can be fixed by C=0 or by a fit (C<0) such as a clearance fit or a press fit.

FIG. 3 is a cross-sectional view taken along the line AA in FIG. Referring to FIG. 3, in this embodiment, the cylindrical portion 2c (opening A) provided in the frame 2 and the elastic member 6 are circular (annular) coaxially arranged when viewed in the axial direction. be. That is, in this embodiment, the axis-perpendicular dimension dc of the gap C is the same along the circumferential direction.

However, according to the present invention, as described above, the axis-perpendicular dimension dc of the gap C can be changed along the circumferential direction. In this case, by adjusting the axis-perpendicular dimension dc of the gap C along the circumferential direction, a vibration isolator can be obtained in which the spring rigidity in the axis-perpendicular direction is easily tuned to a desired spring rigidity.

FIG. 4 is a cross-sectional view of another example of the elastic member 6, taken along the line AA in FIG. 2. As shown in FIG. Referring to FIG. 4, the outer shape of the elastic member 6 is uneven in the circumferential direction when viewed in the axial direction. In this case, by adjusting the shape of the unevenness (for example, the circumferential spacing of the unevenness, the axial height of the convexity, and the axial depth of the concaveness) along the circumferential direction, the spring stiffness in the axial direction can be adjusted to the desired value. This is a vibration isolator that can be easily tuned to the spring stiffness.

FIG. 5 is a cross-sectional view of still another example of the elastic member 6, taken along the line AA in FIG. 2. As shown in FIG. Referring to FIG. 5, the outer shape of the elastic member 6 can be an elongated shape having a long axis and a short axis when viewed in the axial direction. In this case, the long shape (for example, the circumferential direction of the long axis or short axis when viewed in the axial direction, the length of the long axis, the length of the short axis, the shape of the long axis and the short axis when viewed in the axial direction) By adjusting the angle), a vibration isolator can be obtained in which the spring stiffness in the direction perpendicular to the axis can be easily tuned to the desired spring stiffness.

In the example of FIG. 5, the outline shape of the opening A formed in the frame 2 (the shape of the inner circumferential surface 2f of the cylindrical portion 2c) is also an elongated shape having a long axis and a short axis when viewed in the axial direction. It is the shape. In this example, the outline shape of the opening A formed in the frame 2 is an oval shape. Examples of such an oval shape include an elliptical shape. Further, in this example, the long axis direction corresponds to the left-right direction when the vibration isolator 1 is mounted on the vehicle (the left-right direction This corresponds to the front-rear direction when installed (front-rear direction Y when installed on the vehicle). The long axis and short axis for shaping the profile of the opening A formed in the frame 2 coincide with the long axis X and the short axis Y of the elastic member 6. In this example, the gap CX in the major axis direction (left-right direction when installed in a vehicle) is larger than the gap CY in the short axis direction (front-rear direction when installed in a vehicle). Further, when the elastic member 6 has an elongated shape (in this embodiment, an elliptical shape) having a long axis and a short axis as in the present embodiment, the opening A formed in the frame 2 and the elastic member 6 can be made constant in the circumferential direction. Also in this case, as shown in FIG. 5, the outer shape of the elastic member 6, in other words, the thickness of the elastic member 6 changes in the circumferential direction. Therefore, even in such a case, the vibration isolating device can easily tune the spring stiffness in the direction perpendicular to the axis to a desired spring stiffness. However, according to the present invention, the outline shape of the opening A formed in the frame 2 can be made into various shapes.

By the way, referring to FIG. 1, the vibration isolator 1 further includes a frame 2. As shown in FIG. Furthermore, in this embodiment, the opening A formed in the frame 2 is formed by the inner circumferential surface 2f of the cylindrical portion 2c provided in the frame 2. As shown in FIG. 2, in the vibration isolator 1 of FIG. 1, an inner circumferential surface 2f of a cylindrical portion 2c provided in the frame 2 is parallel to the axis O.

On the other hand, FIG. 6 is an enlarged sectional view showing another example of the opening A of the frame 2 corresponding to the area R in FIG. Referring to FIG. 6, in this example, the tip 2fe of the inner circumferential surface 2f of the cylindrical portion 2c provided in the frame 2 expands outward in the axial direction toward the tip 2e of the cylindrical portion 2c. In this case, it is possible to prevent the tip 2e of the cylindrical portion 2c provided on the frame 2 from coming into contact with the elastic member 6. Therefore, in this case, durability is further improved. In particular, in this embodiment, as shown in FIG. 6, the tip 2fe of the inner circumferential surface 2f of the cylindrical portion 2c provided in the frame 2 is axially It is rounded with a curvature of radius r so as to expand outward in the vertical direction. In this case, even if the elastic member 6 comes into contact with the tip 2fe of the inner circumferential surface 2f of the cylindrical portion 2c provided on the frame 2 due to the shaft member 5 being largely inclined with respect to the axis O, the It is possible to prevent contact from concentrating on one location of the tip portion 2fe. Therefore, in this case, durability is further improved.

Further, in the vibration isolator 1 shown in FIG. 1, the shaft member 5 is press-fitted into the elastic member 6. According to the present invention, the elastic member 6 can be fixed to the shaft member 5 by adhesive or non-adhesive. In the vibration isolator 1 shown in FIG. 1, the elastic member 6 is fixed to the shaft member 5 without adhesive. In this case, manufacturing costs can be suppressed. In particular, in the vibration isolator 1 shown in FIG. 1, the shaft member 5 is press-fitted into the elastic member 6. In this case, the elastic member 6 can be firmly fixed to the shaft member 5. Therefore, according to the vibration isolating device 1 of FIG. 1, it is possible to suppress the elastic member 6 from moving in the axial direction with respect to the shaft member 5.

Further, the vibration isolator 1 in FIG. 1 is a cab mount. In this case, the cab mount will be more durable. However, according to the present invention, the vibration isolating device can be applied to a member mount (body mount) of a type that is mounted in a compressed state between members constituting a vehicle, other than a cab mount.

Further, in the vibration isolator 1 of FIG. 1, the upper mount elastic body 3 has at least one depression d formed in at least one of its inner diameter surface (inner peripheral surface) and outer diameter surface (outer peripheral surface). be able to. In this case, the dynamic magnification can be controlled to a desired value, and the deflection under load can be controlled to a constant value. In the vibration isolator 1 shown in FIG. 1, a depression d is formed in the outer peripheral surface of the upper mount elastic body 3. Further, in the vibration isolator 1 shown in FIG. 1, the lower mount elastic body 4 is also formed with a depression d.

Further, in the vibration isolator 1 shown in FIG. 1, the upper mount elastic body 3 includes a stopper portion 1S that limits compressive deformation of the upper mount elastic body 3. In the present embodiment, the stopper portion 1S includes an upper stopper 1S1 and a lower stopper 1S2. In this embodiment, the upper stopper 1S1 is formed by the upper plate 8 (second upper plate 8b). However, the upper stopper 1S1 can also be installed on the cab 7 side. Moreover, in this embodiment, the lower stopper 1S2 is formed of an elastic body. In this embodiment, the lower stopper 1S2 is formed integrally with the upper mount elastic body 3.

What has been described above describes exemplary embodiments of the invention, and various modifications may be made without departing from the scope of the claims. According to the present invention, the spring rigidity of the vibration isolator 1 can be changed in at least one of the following directions: the front direction when mounted on a vehicle, the rear direction when mounted on a vehicle, the right direction when mounted on a vehicle, and the left direction when mounted on a vehicle. . Further, in the present invention, the frame 2 includes a bracket attached to the frame 2. The various configurations adopted in the present embodiment and the exemplary configurations described above can be replaced with each other or combined as appropriate.

1: Vibration isolator, 2: Vehicle frame, 2a: Frame recess, 2c: Frame cylinder, 3: Upper mount elastic body, 4: Lower mount elastic body, 5: Shaft member, 5f: Outer periphery of shaft member surface, 6: elastic member, A: opening

Claims (8)

an upper mount elastic body and a lower mount elastic body that sandwich the vehicle frame;
a shaft member passing through an opening formed in the frame and extending to the upper mount elastic body and the lower mount elastic body;
an elastic member disposed on the outer peripheral surface of the shaft member;
It is equipped with
A gap is formed between the elastic member and the opening in a direction perpendicular to the axis when the elastic member is attached to the vehicle;
The axis-perpendicular dimension of the gap changes along the circumferential direction,
In the vibration isolator, the outer shape of the elastic member is an elongated shape having a long axis and a short axis when viewed in the axial direction . an upper mount elastic body and a lower mount elastic body that sandwich the vehicle frame;
a shaft member passing through an opening formed in the frame and extending to the upper mount elastic body and the lower mount elastic body;
an elastic member disposed on the outer peripheral surface of the shaft member;
It is equipped with
further comprising the frame;
The opening is formed by an inner circumferential surface of a cylindrical portion provided in the frame, and a tip of the inner circumferential surface of the cylindrical portion expands outward in the axial direction toward the tip of the cylindrical portion. Anti -vibration device. The vibration isolator according to claim 2 , wherein an axis-perpendicular gap is formed between the elastic member and the opening when the vibration isolator is attached to the vehicle. The vibration isolator according to claim 3 , wherein the axis-perpendicular dimension of the gap changes along the circumferential direction. The vibration isolator according to claim 4 , wherein the outer shape of the elastic member is an uneven shape along the circumferential direction when viewed in the axial direction. The vibration isolator according to claim 4 , wherein the outer shape of the elastic member is an elongated shape having a long axis and a short axis when viewed in the axial direction. The vibration isolator according to claim 1, wherein the shaft member is press-fitted into the elastic member. The vibration isolator according to claim 1, wherein the vibration isolator is a cab mount.

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