Cylindrical vibration control device for vehicle auxiliary machine

Abstract

Provided is a cylindrical vibration control device for a vehicle auxiliary machine having a novel structure, in which a main-body rubber elastic body having a low spring characteristic suitable for a vehicle auxiliary machine can be employed.　A cylindrical vibration control device 10 for a vehicle auxiliary machine is provided with an inner shaft member 16 and an outer bracket 14 attached to one of a vehicle auxiliary machine 32 and a vehicle-body-side support member 34. A cylindrical part 44 externally fitted over the inner shaft member 16 is provided to the outer bracket 14. The inner shaft member 16 and the cylindrical part 44 are connected by a main-body rubber elastic body 20. The inner shaft member 16 is provided with a stopper protrusion 24 that protrudes to the outer-peripheral side at a position protruding in an axial direction from the main-body rubber elastic body 20. The outer bracket 14 is provided with a first stopper part 46 having an axis-perpendicular contact surface 48 opposing the stopper protrusion 24 in a direction perpendicular to the axis, and a second stopper part 50 having an axial-direction contact surface 52 opposing the stopper protrusion 24 in the axial direction, at positions protruding in the axial direction from the main-body rubber elastic body 20.

Description

Cylindrical vibration isolation device for vehicle accessories

[0001] The present invention relates to a cylindrical vibration isolation device for vehicle accessories that supports vehicle accessories such as electric compressors in a vibration-isolating manner.

[0002] Conventionally, cylindrical vibration-damping devices for vehicle accessories, which support vehicle accessories such as electric compressors on a vehicle body in a vibration-damping manner, have been known. As shown, for example, in the main bush 130 of U.S. Pat. No. 11,078,985 (Patent Document 1), cylindrical vibration-damping devices for vehicle accessories have a structure in which an inner shaft member and an outer bracket having a cylindrical portion are connected by a main rubber elastic body.

[0003] U.S. Pat. No. 11,078,985

[0004] However, since vehicle accessories such as electric compressors are relatively lightweight and the input load to the vibration isolation device is small, cylindrical vibration isolation devices for vehicle accessories are required to have softer spring characteristics than cylindrical vibration isolation devices used in engine mounts and suspension bushings.

[0005] However, if an attempt is made to achieve soft spring characteristics by reducing the spring constant of the main rubber elastomer, the main rubber elastomer may deform more, or may break due to the heavy load during a vehicle collision or due to deterioration of the main rubber elastomer over time. Furthermore, large deformation or breakage of the main rubber elastomer may cause damage to the vehicle accessories by colliding with other surrounding components or the ground. With increasing awareness of environmental issues, for example, if an electric compressor, which is a vehicle accessory, is damaged or its piping becomes loose, there are concerns about the environmental impact caused by refrigerant leakage.

[0006] An object of the present invention is to provide a cylindrical vibration-damping device for vehicle accessories having a novel structure that enables the use of a main rubber elastic body with the low spring characteristics required for vehicle accessories.

[0007] The following describes preferred embodiments for understanding the present invention, but the embodiments described below are merely examples and may be appropriately combined with one another. Multiple components described in each embodiment may be recognized and employed independently to the greatest extent possible, and may also be appropriately combined with any of the components described in other embodiments. Accordingly, the present invention is not limited to the embodiments described below, and various other embodiments may be realized.

[0008] The first aspect is a cylindrical vibration-damping device for a vehicle accessory that supports the vehicle accessory on a support member on the vehicle body side in a vibration-damping manner, and includes an inner axial member attached to one of the vehicle accessory and the support member, an outer bracket attached to the other of the vehicle accessory and the support member and having a tubular portion arranged spaced apart on the outer periphery of the inner axial member, and a main rubber elastic body that connects the inner axial member and the tubular portion of the outer bracket, and the inner axial member is provided with a stopper protrusion that protrudes outer periphery at a position protruding axially from the main rubber elastic body, and the outer bracket is provided with a first stopper portion at a position protruding axially from the main rubber elastic body and having an axial abutment surface that faces the stopper protrusion at a distance perpendicular to the axis, and a second stopper portion that has an axial abutment surface that faces the stopper protrusion at a distance axially.

[0009] A cylindrical vibration-damping device for a vehicle accessory, which supports and vibration-damps vehicle accessories that are lighter than the vehicle main engine, is required to have softer spring characteristics (low spring characteristics) than a cylindrical vibration-damping device for a vehicle main engine. However, if the spring characteristics for normal vibration input are set low enough for a vehicle accessory, the relative displacement between the vehicle accessory and the support member on the vehicle body side becomes excessively large when a large load is input, causing problems such as contact between the vehicle accessory and other surrounding components or the ground. Therefore, in a cylindrical vibration-damping device for a vehicle accessory constructed according to this embodiment, the relative displacement between the inner shaft member and the outer bracket is limited by the abutment of the stopper protrusion of the inner shaft member with the first and second stopper portions of the outer bracket. This makes it possible to limit the relative displacement between the vehicle accessory and the support member on the vehicle body side, preventing contact between the vehicle accessory and other surrounding components or the ground, while setting the low spring characteristics required of a cylindrical vibration-damping device for a vehicle accessory.

[0010] Furthermore, if the deformation of the main rubber elastic body becomes large when a large load is input, it is conceivable that the main rubber elastic body may break; however, since the deformation of the main rubber elastic body is limited by the contact between the stopper projection and the first and second stopper portions, excessive deformation of the main rubber elastic body is avoided, and breakage of the main rubber elastic body can also be prevented.

[0011] Even if the main rubber elastic body were to break, the abutment between the stopper protrusion of the inner shaft member and the second stopper portion of the outer bracket prevents separation between the inner shaft member and the outer bracket. This prevents the vehicle accessory from separating and falling off the vehicle body, and prevents damage to the vehicle accessory from hitting the ground. Moreover, because the amount of relative displacement between the inner shaft member and the outer bracket in the axis-perpendicular direction is limited by the abutment between the stopper protrusion and the first stopper portion, it is difficult for the axial opposing state between the stopper protrusion and the second stopper portion to be released, and therefore the vehicle accessory is reliably prevented from falling off the support member.

[0012] In a second aspect, in the cylindrical vibration-damping device for vehicle accessories described in the first aspect, the stopper protrusion is a flange portion that protrudes outward around the entire circumference of the inner shaft member, the outer bracket is provided with a cylindrical peripheral wall portion that extends cylindrically outward in the axial direction from the cylindrical portion, the first stopper portion is formed by the cylindrical peripheral wall portion, and the second stopper portion is formed by an inner flange portion that protrudes annularly from the cylindrical peripheral wall portion toward the inner circumference.

[0013] In a cylindrical vibration-damping device for a vehicle accessory constructed according to this aspect, the amount of relative axial displacement between the vehicle accessory and the support member is limited by the abutment between the flange portion that is continuous around the entire circumference and the annular inner flange portion, ensuring a large abutment area and dispersing the stopper load. In addition, the amount of relative tilting displacement between the inner shaft member and the outer bracket in the prying direction is also limited by the abutment between the flange portion and the inner flange portion.

[0014] In addition, since the amount of relative displacement between the vehicle accessory and the support member in the axis-perpendicular direction is limited by the abutment between the flange portion and the cylindrical peripheral wall portion, the amount of relative displacement between the inner shaft member and the outer bracket can be limited in all axis-perpendicular directions.

[0015] In a third aspect, in the cylindrical vibration-damping device for vehicle accessories described in the first or second aspect, a stopper rubber is provided between the stopper protrusion and the outer bracket, and the stopper rubber is configured to include an axial buffer rubber arranged between the opposing surfaces of the stopper protrusion and the first stopper portion, and an axial buffer rubber arranged between the opposing surfaces of the stopper protrusion and the second stopper portion.

[0016] In a cylindrical vibration-damping device for vehicle accessories constructed in accordance with this embodiment, the stopper rubber arranged between the stopper protrusion and the outer bracket comprises axial buffer rubber and axial buffer rubber, and therefore, when the stopper protrusion comes into contact with the first stopper portion and when the stopper protrusion comes into contact with the second stopper portion, the impact noise and shock are reduced by the buffering properties of the stopper rubber.

[0017] The fourth aspect is a cylindrical vibration-damping device for vehicle accessories described in the third aspect, in which the stopper rubber is formed integrally with the main rubber elastic body and fixed to the stopper protrusion of the inner shaft member.

[0018] In a cylindrical vibration-damping device for vehicle accessories constructed in accordance with this embodiment, the stopper rubber, which includes the axial buffer rubber and the axial buffer rubber, is integrally formed with the main rubber elastic body and fixed to the stopper protrusion, thereby eliminating the need for a process for forming the stopper rubber separately from the main rubber elastic body, making manufacturing easier and reducing the number of parts.

[0019] A fifth aspect is the cylindrical vibration-damping device for a vehicle accessory according to any one of the first to fourth aspects, wherein the vehicle accessory is an electric compressor.

[0020] According to the cylindrical vibration-damping device for vehicle accessories constructed in accordance with this embodiment, even if the vehicle accessory is an electric compressor that generates vibrations when in operation, the device is supported in a vibration-damping manner on a support member on the vehicle body side, thereby suppressing the transmission of vibrations to the support member side.

[0021] Furthermore, because electric compressors are significantly lighter than main vehicle machinery such as engines, the main rubber elastic body is required to have softer spring characteristics. If the spring constant of the main rubber elastic body were to be set smaller, the amount of deformation of the main rubber elastic body would increase when a large load is input, making it more susceptible to breakage. However, because the relative displacement of the inner shaft member and outer bracket is limited in both the transverse and axial directions, excessive deformation of the main rubber elastic body is avoided, preventing interference with other components due to displacement of the electric compressor or contact with the ground due to falling off.

[0022] Furthermore, for example, if the electric compressor comes into contact with other members or the ground and is damaged, or if the electric compressor piping becomes loose, there is a risk of refrigerant leaking from the electric compressor, which has a negative impact on the environment. Therefore, by using a stopper mechanism in which the stopper protrusion of the inner shaft member abuts against the first and second stopper portions of the outer bracket, the electric compressor is prevented from coming into contact with other members or the ground, thereby preventing refrigerant leakage due to damage to the electric compressor and environmental pollution, etc.

[0023] The sixth aspect is a cylindrical vibration-damping device for vehicle accessories described in any one of the first to fifth aspects, in which an outer cylindrical member is arranged at a distance from the outer periphery of the inner shaft member and fixed to the main rubber elastic body, and the outer cylindrical member is press-fitted and fixed into the cylindrical portion of the outer bracket.

[0024] In a cylindrical vibration-damping device for vehicle accessories constructed according to this aspect, the outer tubular member, which is a separate member from the outer bracket attached to the vehicle accessory or a support member on the vehicle body, is fixed to the main rubber elastic body, so that the outer tubular member fixed to the main rubber elastic body does not need to be provided with a structure for attaching it to the support member on the vehicle body. This makes it possible to reduce the size of the vulcanization-molded product of the main rubber elastic body before the outer bracket is attached, thereby improving production efficiency.

[0025] The seventh aspect is a cylindrical vibration-damping device for vehicle accessories described in any one of the first to sixth aspects, wherein the central axis of the inner shaft member extends in the vertical direction of the vehicle, the vehicle accessories are attached to the lower side of the inner shaft member, and the outer bracket is attached to the support member above the vehicle accessories.

[0026] According to the cylindrical vibration-damping device for vehicle accessories constructed in accordance with this embodiment, the vehicle accessories are supported in a suspended state, and when the main rubber elastic body breaks, gravity causes the vehicle accessories to displace downward relative to the vehicle body.However, the abutment between the stopper protrusion and the second stopper portion prevents the vehicle accessories from separating from the vehicle body and falling off.

[0027] An eighth aspect is a cylindrical vibration-damping device for vehicle accessories described in any one of the first to seventh aspects, wherein the stopper protrusion is integrally formed with the inner shaft member.

[0028] According to the cylindrical vibration-damping device for vehicle accessories constructed according to this aspect, the number of parts can be reduced compared to when the stopper projection is formed as a separate part from the inner shaft member.

[0029] According to the present invention, in a cylindrical vibration-damping device for vehicle accessories, it is possible to employ a main rubber elastic body having low spring characteristics required for vehicle accessories.

[0030] 3 is a right side view of the anti-vibration mount shown in FIG. 3 when mounted on a vehicle; FIG. 3 is a vertical cross-sectional view of the anti-vibration mount shown in FIG. 1 when mounted on a vehicle, showing a state in which the electric compressor has been displaced downward; FIG. 3 is a vertical cross-sectional view of the anti-vibration mount shown in FIG. 1 when mounted on a vehicle, showing a state in which the electric compressor has been displaced upward;

[0031] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0032] 1 shows an anti-vibration mount 10 for an electric compressor as a first embodiment of a cylindrical anti-vibration device for vehicle accessories according to the present invention. The anti-vibration mount 10 has a structure in which an outer bracket 14 is attached to a mount body 12. In the following description, the up-down direction generally refers to the vertical up-down direction, which is the direction of the mount's central axis, as seen in FIG. 1.

[0033] As shown in Figure 2, the mount body 12 has a structure in which an inner shaft member 16 is inserted into an outer cylindrical member 18, and the inner shaft member 16 and the outer cylindrical member 18 are elastically connected radially by a cylindrical main rubber elastic body 20.

[0034] The inner shaft member 16 is a small-diameter cylindrical member made of metal, fiber-reinforced synthetic resin, or the like, and extends linearly in the vertical direction. The inner hole of the inner shaft member 16 is a bolt hole 22 that has a circular cross section and penetrates in the axial direction.

[0035] A stopper projection 24 is formed in the axially intermediate portion of the inner shaft member 16, projecting outward in the direction perpendicular to the axis. The stopper projection 24 is an annular plate-shaped flange portion that is provided continuously around the entire circumference with a substantially constant cross-sectional shape. The stopper projection 24 is provided below the axial center of the inner shaft member 16. In this embodiment, the stopper projection 24 is formed integrally with the inner shaft member 16, but, for example, the annular plate-shaped stopper projection may be a separate part from the inner shaft member, and the stopper projection may be provided by being externally fitted onto the outer peripheral surface of the inner shaft member.

[0036] The outer cylindrical member 18 is made of metal, fiber-reinforced synthetic resin, or the like, and has a generally cylindrical shape with a thinner wall and a larger diameter than the inner axial member 16. In this embodiment, the outer cylindrical member 18 extends straight in the axial direction with generally constant inner and outer diameters. The axial length of the outer cylindrical member 18 is smaller than the axial length of the inner axial member 16, and is preferably no more than half, and more preferably no more than one-third, of the length of the inner axial member 16.

[0037] The inner shaft member 16 is inserted into the inner peripheral side of the outer cylindrical member 18. The upper and lower ends of the inner shaft member 16 protrude outward from the outer cylindrical member 18, and the inner shaft member 16 is disposed so as to protrude further downward than upward from the outer cylindrical member 18. The stopper projection 24 of the inner shaft member 16 is positioned below and spaced apart from the outer cylindrical member 18.

[0038] The inner shaft member 16 and the outer cylindrical member 18, which are arranged in an internally and externally inserted state as described above, are connected to each other by a main rubber elastic body 20. The main rubber elastic body 20 is shaped like an upside-down truncated cone whose diameter decreases downward as it goes overall, and its inner peripheral end is vulcanization bonded to the inner shaft member 16, while its outer peripheral end is vulcanization bonded to the outer cylindrical member 18.

[0039] The stopper protrusion 24 of the inner shaft member 16 is positioned to protrude downward from the main rubber elastic body 20, and the lower end of the main rubber elastic body 20 is fixed to the upper surface of the stopper protrusion 24. The stopper protrusion 24 is covered by a first stopper rubber 26 serving as a stopper rubber. The first stopper rubber 26 includes an axial buffer rubber 28 that covers the outer peripheral surface of the stopper protrusion 24, which faces the axial abutment surface 48 (described later), and an axial buffer rubber 30 that covers the lower surface of the stopper protrusion 24, which faces the axial abutment surface 52 (described later). In this embodiment, the first stopper rubber 26 is integrally formed with the main rubber elastic body 20 and is vulcanization-bonded to the inner shaft member 16 together with the main rubber elastic body 20. In this embodiment, the axial buffer rubber 28 is thicker than the axial buffer rubber 30. The first stopper rubber 26 is integrally continuous with the main rubber elastic body 20 at the upper end of the axial buffer rubber 28. The first stopper rubber 26 protrudes slightly downward from the inner peripheral end of the axial buffer rubber 30 and is fixed to the outer peripheral surface of the inner shaft member 16 below the stopper projection 24 .

[0040] As shown in Figure 1, the mount body 12 constructed as described above is interposed between an electric compressor 32, which serves as a vehicle accessory, and an outer bracket 14 fixed to a support member 34 on the vehicle body side. That is, the mount body 12 is mounted on the vehicle by attaching the inner shaft member 16 to the electric compressor 32 and the outer cylindrical member 18 to the outer bracket 14 fixed to the support member 34. When the mount body 12 is mounted on the vehicle, the electric compressor 32 is connected in a vibration-isolating manner to the support member 34 on the vehicle body side via the vibration-isolating mount 10, as shown in Figures 3 to 6.

[0041] 3 and 5, in this embodiment, the electric compressor 32 is connected in a vibration-damping manner to a support member 34 on the vehicle body side by three mount bodies 12, 12, 12, but in the following explanation, only the vehicle-mounted state of one mount body 12 will be explained, and the other two will not be explained as they are similar. In this embodiment, the three mount bodies 12, 12, 12 are attached to one outer bracket 14, but each combination of the mount body 12 and the outer bracket 14 constitutes an anti-vibration mount 10, so that the electric compressor 32 is supported in a vibration-damping manner by three anti-vibration mounts 10, 10, 10, as shown in FIG.

[0042] As shown in Fig. 1 , the lower end surface of the inner shaft member 16 is placed on the upper surface of a fastening portion 38 that protrudes from the housing 36 of the electric compressor 32, and the inner shaft member 16 is bolted to the electric compressor 32 by a bolt 40 that is inserted through the bolt hole 22 of the inner shaft member 16 and the bolt hole 22 that passes vertically through the fastening portion 38. In Fig. 5 , the inner shaft member 16 and the fastening portion 38 of the electric compressor 32 are fastened together by a nut 42 that is threaded onto the bolt 40, but the bolt 40 may also be threaded into a threaded hole formed in the fastening portion 38, for example. The housing 36 of the electric compressor 32 is hollow and cylindrical, and houses a compressor main body (not shown) therein.

[0043] The outer tubular member 18 is press-fitted and fixed into a tubular portion 44 provided on the outer bracket 14. In this embodiment, the outer tubular member 18, which is vulcanization-bonded to the main rubber elastic body 20, and the outer bracket 14, which is fixed to a support member 34 on the vehicle body side, are separate components, and by press-fitting the outer tubular member 18 into the outer bracket 14, the tubular portion 44 of the outer bracket 14 is positioned at a distance from the outer periphery of the inner shaft member 16, and the inner shaft member 16 and the tubular portion 44 of the outer bracket 14 are interconnected by the main rubber elastic body 20. This structure in which the outer tubular member 18 and the outer bracket 14 are separate components enables the mount main body 12, which is an integrally vulcanization-molded product of the main rubber elastic body 20, to be made smaller. Note that the vibration-proof mount 10 of this embodiment has a structure in which the outer bracket 14 is attached to the mount main body 12.

[0044] The outer bracket 14 is provided with a cylindrical peripheral wall portion 46 that protrudes downward from the cylindrical portion 44, and the cylindrical peripheral wall portion 46 extends downward further than the stopper projection 24 of the inner shaft member 16. The cylindrical peripheral wall portion 46, which serves as a first stopper portion, surrounds the outer periphery of the stopper projection 24, and the inner periphery that faces the outer periphery of the stopper projection 24 in the radial direction serves as a shaft abutment surface 48.

[0045] An inner flange-shaped portion 50 is provided at the lower end of the cylindrical peripheral wall portion 46, protruding annularly inward along the entire circumference as a second stopper portion. The inner flange-shaped portion 50 is located below the stopper protrusion 24 of the inner shaft member 16, with its inner peripheral end facing the stopper protrusion 24 in the up-down direction and spaced outward from the portion of the inner shaft member 16 below the stopper protrusion 24. In the vibration-proof mount 10, the axial buffer rubber 30 covering the underside of the stopper protrusion 24 of the inner shaft member 16 faces the inner flange-shaped portion 50 of the outer bracket 14 at a predetermined stopper clearance above. Furthermore, the axial buffer rubber 28 covering the outer peripheral surface of the stopper protrusion 24 faces the inner peripheral surface of the cylindrical peripheral wall portion 46 at a predetermined stopper clearance. The inner flange portion 50 has an upper surface that faces the lower surface of the stopper projection 24 in the vertical direction and serves as an axial contact surface 52 .

[0046] A second stopper rubber 54 is fixed to the underside of the inner flange-shaped portion 50. The second stopper rubber 54 is annular and is superimposed on the underside of the inner peripheral end of the inner flange-shaped portion 50. When the vibration-proof mount 10 is installed on a vehicle, the underside of the second stopper rubber 54 faces the fastening portion 38 of the electric compressor 32 above, separated by a predetermined stopper clearance.

[0047] The mount body 12 is attached to the vehicle with the central axis of the inner shaft member 16 extending in the vertical direction of the vehicle, the electric compressor 32 is attached to the lower side of the inner shaft member 16, and the outer bracket 14 is attached to the support member 34 above the electric compressor 32. Therefore, the electric compressor 32 is supported in a vibration-isolating state in a suspended state via the vibration-isolating mount 10 relative to the support member 34 on the vehicle body side.

[0048] When vibrations caused by the operation of the electric compressor 32 or the like are input between the inner shaft member 16 and the outer cylindrical member 18 with the vibration-isolating mount 10 installed in the vehicle, the intended vibration-isolating effect is achieved by the vibration-insulating and vibration-damping effects that occur when the main rubber elastic body 20 elastically deforms. During normal vibration input as shown in Figure 6, the first stopper rubber 26 covering the stopper projection 24 is maintained spaced apart from the cylindrical peripheral wall portion 46 and inner flange portion 50 of the outer bracket 14. During normal vibration input, the fastening portion 38 of the electric compressor 32 is maintained spaced downward from the second stopper rubber 54 covering the underside of the inner flange portion 50 of the outer bracket 14.

[0049] 7 , when the electric compressor 32 is displaced significantly downward relative to the support member 34 on the vehicle body side, the stopper protrusion 24 of the inner shaft member 16 fixed to the electric compressor 32 comes into contact in the vertical direction with the axial abutment surface 52 of the inner flange portion 50 of the outer bracket 14 via the axial buffer rubber 30 of the first stopper rubber 26. This forms a first stopper mechanism 56 that limits the amount of downward relative displacement of the inner shaft member 16 with respect to the outer cylindrical member 18, thereby limiting the downward displacement of the electric compressor 32 with respect to the support member 34. This prevents the electric compressor 32 from hitting the ground or other surrounding members, thereby preventing damage to the electric compressor 32 or other members.

[0050] 7 shows an example in which the first stopper mechanism 56 is configured in a state in which the inner shaft member 16 and the outer cylindrical member 18 are connected by the main rubber elastic body 20, but even if, for example, an impactful large load causes the main rubber elastic body 20 to break and the connection between the inner shaft member 16 and the outer cylindrical member 18 by the main rubber elastic body 20 is released, the electric compressor 32 will fall downward, thereby configuring the first stopper mechanism 56. Therefore, even when the main rubber elastic body 20 breaks, the first stopper mechanism 56 prevents the electric compressor 32 from falling downward.

[0051] Furthermore, when the electric compressor 32 is displaced significantly radially relative to the support member 34 on the vehicle body side, the stopper protrusion 24 of the inner shaft member 16 and the axially-directed abutment surface 48 of the tubular circumferential wall portion 46 of the outer bracket 14 abut in the radial direction via the axially-directed cushioning rubber 28. This forms a second stopper mechanism 58 that limits the amount of relative radial displacement between the inner shaft member 16 and the outer tubular member 18, thereby limiting the radial displacement of the electric compressor 32 relative to the support member 34. This prevents the electric compressor 32 from hitting the outer bracket 14 or other surrounding components, thereby preventing damage to the electric compressor 32, the outer bracket 14, and other surrounding components. In this embodiment, the stopper protrusion 24 and the tubular circumferential wall portion 46 are provided continuously around the entire circumference, so the second stopper mechanism 58 is formed in the entire radial direction.

[0052] 8 , when the electric compressor 32 is displaced significantly upward relative to the support member 34 on the vehicle body side, the fastening portion 38 of the electric compressor 32 comes into contact with the inner flange portion 50 of the outer bracket 14 in the vertical direction via the second stopper rubber 54. This forms a third stopper mechanism 60 that limits the amount of upward relative displacement of the inner shaft member 16 with respect to the outer tubular member 18, thereby limiting the upward displacement of the electric compressor 32 with respect to the support member 34. This prevents the electric compressor 32 from hitting the outer bracket 14, and prevents damage to the electric compressor 32 and the outer bracket 14.

[0053] In addition, like the first stopper mechanism 56, the second stopper mechanism 58 and the third stopper mechanism 60 limit the amount of relative displacement between the inner shaft member 16 and the outer cylindrical member 18 even when the main rubber elastic body 20 breaks.

[0054] As described above, the anti-vibration mount 10 according to this embodiment limits the amount of relative displacement of the electric compressor 32 with respect to the vehicle body (support member 34) when a large load is input, thereby preventing damage to the electric compressor 32, for example, when the electric compressor 32 strikes other members, the ground, etc. In particular, because the electric compressor 32 used in a vehicle air conditioner or the like has a refrigerant flowing inside, if the electric compressor 32 is damaged by striking other members or the ground, there is a risk that the refrigerant may leak to the outside and pollute the surrounding environment. However, by employing the anti-vibration mount 10 according to this embodiment, damage to the electric compressor 32 is prevented, thereby preventing environmental pollution due to refrigerant leakage.

[0055] Because the electric compressor 32, which is a vehicle accessory, is significantly lighter than the vehicle's main engine (such as an engine), the main rubber elastic body 20 is required to have spring characteristics softer than those of the main rubber elastic body of a cylindrical vibration isolation device for the vehicle's main engine, such as an engine mount. However, if the spring constant of the main rubber elastic body 20 is set smaller, the main rubber elastic body 20 will deform more when a large load is applied, making it more susceptible to breakage. Therefore, by providing the vibration isolation mount 10 with first to third stopper mechanisms 56, 58, and 60 that limit the relative displacement of the inner shaft member 16 and the outer bracket 14 in the axial direction and the axis-perpendicular direction, respectively, excessive deformation of the main rubber elastic body 20 and any resulting damage can be avoided, and the electric compressor 32 can be prevented from striking other components, the ground, etc.

[0056] In this embodiment, the anti-vibration mount 10 is attached to the vehicle with the central axis of the inner shaft member 16 extending in the vertical direction of the vehicle, the electric compressor 32 is attached below the inner shaft member 16, and the outer bracket 14 is attached to the support member 34 above the electric compressor 32. In such a structure in which the electric compressor 32 is supported by the anti-vibration mount 10 in a suspended state, for example, if the main rubber elastic body 20 breaks, the inner shaft member 16 will be displaced axially downward relative to the outer bracket 14 due to gravity, but in such a case the first stopper mechanism 56 will prevent the electric compressor 32 from falling off.

[0057] In the vibration-proof mount 10, the stopper protrusions 24 constituting the first and second stopper mechanisms 56, 58 are flanges that are continuously provided around the entire circumference. This ensures a large contact area between the stopper protrusions 24 and the inner flange portion 50 in the first stopper mechanism 56, thereby distributing the stopper load and reducing impact noise and improving the durability of the axial buffer rubber 30. Furthermore, because the second stopper mechanism 58 can be configured around the entire circumference, the amount of relative displacement between the inner axial member 16 and the outer tubular member 18 can be limited in response to any radial input. Furthermore, since the mount body 12 does not need to be positioned circumferentially when mounted on the vehicle, the mounting process on the vehicle is simplified. Even when the inner axial member 16 and the outer tubular member 18 are displaced relative to each other in a twisting direction, the amount of relative displacement can be limited by the contact between the stopper protrusions 24 and the inner flange portion 50.

[0058] In both the first and second stopper mechanisms 56, 58, the first stopper rubber 26 is interposed between the abutment surfaces of the stopper projection 24 and the outer bracket 14, thereby reducing the impact and sound generated when the stopper projection 24 and the outer bracket 14 come into contact. In this embodiment, the first stopper rubber 26 is formed integrally with the main rubber elastic body 20, thereby reducing the number of parts. In addition, in the third stopper mechanism 60, the second stopper rubber 54 is interposed between the abutment surfaces of the fastening portion 38 of the electric compressor 32 and the outer bracket 14, thereby reducing the impact and sound generated when the fastening portion 38 and the outer bracket 14 come into contact.

[0059] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the specific descriptions. For example, the stopper projection, first stopper portion, and second stopper portion may be provided continuously around the entire circumference as long as they exert the intended function of limiting the deformation of the main rubber elastic body by abutting in the axial direction or the axis-perpendicular direction. They may also be provided partially around the circumference. When the stopper projection is provided partially around the circumference, it is desirable that the stopper projection be provided so as to protrude on both sides of at least one radial direction so that an axis-perpendicular stopper mechanism (second stopper mechanism 58) is formed on both sides of at least one radial direction.

[0060] Furthermore, although the specific shape and size of the stopper projection 24 are not limited, considering the effect on the vibration-damping characteristics of the main rubber elastic body 20, it is desirable that the tip diameter of the stopper projection 24 be smaller than the outer diameter dimension of the main rubber elastic body 20. Furthermore, taking into consideration the support mode and structure of the electric compressor (vehicle accessory) 32, it is also possible to configure the third stopper mechanism 60 using the stopper projection 24. Specifically, for example, a radially inward convex portion that is located at the axial end of the outer cylindrical member 18 and protrudes toward the inner periphery may be formed, and the abutment action of the stopper projection 24 against this radially inward convex portion may constitute a third stopper mechanism that limits the axial deformation of the main rubber elastic body 20 and prevents the inner shaft member 16 from slipping out of the outer cylindrical member 18 in the axial direction in the event of fracture of the main rubber elastic body 20.

[0061] In the above embodiment, an example was shown in which the main rubber elastic body 20 is fixed to the outer tubular member 18, and the outer tubular member 18 is pressed into and fixed to the outer bracket 14, thereby elastically connecting the inner shaft member 16 and the outer bracket 14 via the main rubber elastic body 20. However, for example, the main rubber elastic body 20 may be fixed directly to the inner surface of the tubular portion 44 of the outer bracket 14.

[0062] When multiple mount bodies are attached to the outer bracket 14 as in the above embodiment, it is sufficient that at least one mount body constitutes a cylindrical vibration-damping device according to the present invention, and it is not necessary that all of the mount bodies constitute cylindrical vibration-damping devices according to the present invention. Note that one mount body may be attached to one outer bracket.

[0063] The third stopper mechanism 60 exemplified in the above embodiment is not essential to the cylindrical vibration damping device according to the present invention and can be omitted, as can be seen from the fact that the electric compressor 32 is a constituent part of the third stopper mechanism 60. Furthermore, a stopper mechanism that limits the amount of upward displacement of the inner shaft member 16 relative to the outer bracket 14, which corresponds to the third stopper mechanism 60, may be provided in the cylindrical vibration damping device.

[0064] In the above embodiment, the first stopper rubber 26 is fixed to the surface of the stopper projection 24, but the stopper rubber may be disposed between the opposing surfaces of the stopper projection 24 and the outer bracket 14. For example, the stopper rubber may be provided free from both the stopper projection 24 and the outer bracket 14, or may be fixed to the outer bracket 14. Specifically, for example, the stopper rubber may be fixed to the inner circumferential surface (axial contact surface 48) of the cylindrical peripheral wall portion 46 of the outer bracket 14 and to the upper surface (axial contact surface 52) of the inner flange-shaped portion 50. In this case, the stopper rubber is separate from the main rubber elastic body 20 and may be formed integrally with the second stopper rubber 54 fixed to the lower surface of the inner flange-shaped portion 50, for example.

[0065] The vehicle accessory is not limited to the illustrated electric compressor 32. However, it is desirable that the vehicle accessory be lighter than the main vehicle engine (internal combustion engine, etc.) that provides the driving force for the vehicle.

[0066] REFERENCE SIGNS LIST 10 Vibration-damping mount (cylindrical vibration-damping device for vehicle accessories, first embodiment) 12 Mount body 14 Outer bracket 16 Inner shaft member 18 Outer cylindrical member 20 Main rubber elastic body 22 Bolt hole 24 Stopper protrusion 26 First stopper rubber (stopper rubber) 28 Axial buffer rubber 30 Axial buffer rubber 32 Electric compressor 34 Support member 36 Housing 38 Fastening portion 40 Bolt 42 Nut 44 Cylindrical portion 46 Cylindrical peripheral wall portion (first stopper portion) 48 Axial abutment surface 50 Inner flange-shaped portion (second stopper portion) 52 Axial abutment surface 54 Second stopper rubber 56 First stopper mechanism 58 Second stopper mechanism 60 Third stopper mechanism

Claims

1. A cylindrical vibration-damping device for a vehicle accessory that supports a vehicle accessory on a support member on a vehicle body side in a vibration-damping manner, comprising: an inner axial member attached to one of the vehicle accessory and the support member; an outer bracket attached to the other of the vehicle accessory and the support member, the outer axial member having a tubular portion arranged at a distance from the outer periphery of the inner axial member; and a main rubber elastic body connecting the inner axial member and the tubular portion of the outer bracket, the inner axial member being provided with a stopper projection that projects outwardly at a position protruding axially from the main rubber elastic body, and the outer bracket being provided with a first stopper portion at a position protruding axially from the main rubber elastic body, the first stopper portion having an axial abutment surface that faces the stopper projection at a distance perpendicular to the axis, and a second stopper portion having an axial abutment surface that faces the stopper projection at a distance from the axis.

2. A cylindrical vibration-damping device for vehicle accessories as described in claim 1, wherein the stopper projection is a flange portion that protrudes outwardly around the entire circumference of the inner shaft member, the outer bracket is provided with a cylindrical peripheral wall portion that extends axially outwardly from the cylindrical portion, the first stopper portion being formed by the cylindrical peripheral wall portion, and the second stopper portion is formed by an inner flange portion that protrudes annularly from the cylindrical peripheral wall portion towards the inner circumference.

3. A cylindrical vibration-damping device for vehicle accessories as described in claim 1 or 2, wherein a stopper rubber is provided between the stopper protrusion and the outer bracket, and the stopper rubber is configured to include an axial cushioning rubber arranged between the opposing surfaces of the stopper protrusion and the first stopper portion, and an axial cushioning rubber arranged between the opposing surfaces of the stopper protrusion and the second stopper portion.

4. A cylindrical vibration-isolating device for vehicle accessories as set forth in claim 3, wherein said stopper rubber is formed integrally with said main rubber elastic body and fixed to said stopper projection of said inner shaft member.

5. A cylindrical vibration isolation device for a vehicle auxiliary machine according to claim 1 or 2, wherein the vehicle auxiliary machine is an electric compressor.

6. A cylindrical vibration-damping device for vehicle accessories as claimed in claim 1 or 2, further comprising an outer tubular member fixed to the main rubber elastic body and spaced apart from the outer periphery of the inner shaft member, the outer tubular member being press-fitted and fixed into the tubular portion of the outer bracket.

7. A cylindrical vibration isolation device for vehicle accessories as described in claim 1 or 2, wherein the central axis of the inner shaft member extends in the vertical direction of the vehicle, the vehicle accessories are attached to the lower side of the inner shaft member, and the outer bracket is attached to the support member above the vehicle accessories.

8. A cylindrical vibration-isolating device for vehicle accessories according to claim 1 or 2, wherein said stopper projection is integrally formed with said inner shaft member.

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