An engine mount apparatus may include a mount housing which has an internal space; a partition device which partitions the internal space into an upper space and a lower space; a nozzle plate which is provided in the upper space and allows a fluid to selectively pass through the nozzle plate; an upper diaphragm which is fastened to an upper surface of the nozzle plate and defines an upper liquid chamber; a core which penetrates the partition device, and has an upper portion disposed in the upper space, and a lower portion disposed in the lower space; a lower diaphragm which extends from the upper portion of the core to a lower surface of the nozzle plate, and defines a lower liquid chamber; and a rubber member which is provided in the upper space, and connects the upper portion of the core and the partition device.

A liquid-sealed antivibration device is equipped with a shaft member and a sleeve member, an antivibration base body constituted by a rubber-like elastic body which elastically supports the sleeve member relative to the shaft member and which defines a first liquid chamber and a second liquid chamber between the shaft member and the sleeve member, and an orifice forming member made of a synthetic resin and disposed inside the sleeve member. The orifice forming member is formed with end surfaces on which a hole portion piercing along the axis of the shaft member opens, and an outer peripheral surface adhered closely to the sleeve member to form a groove portion becoming an orifice which makes the first liquid chamber communicate with the second liquid chamber, and recesses formed at corner portions defined by the end surfaces and the outer peripheral surface are connected to the hole portion.

A vibration damping device including a main rubber elastic body elastically connecting first and second mounting members. An upper portion of the main rubber elastic body constitutes a small-diameter portion to which the first mounting member is bonded, while a lower portion thereof constitutes a large-diameter portion to which the second mounting member is bonded. The first mounting member includes an inner recess opening onto an outer circumferential surface thereof, and the small-diameter portion of the main rubber elastic body is bonded to the inner recess. The main rubber elastic body has an outside diameter dimension made larger at a portion bonded to the inner recess than an outside diameter dimension of the first mounting member at a lower side than the inner recess such that the small-diameter portion of the main rubber elastic body is thick-walled by being bonded to the inner recess.

An engine mount includes: an insulator disposed in a case which has a liquid chamber; an orifice plate dividing the liquid chamber into an upper liquid chamber and a lower liquid chamber, the orifice plate dividing the upper liquid chamber together with the insulator and having an orifice therein for inducing flow of fluid between the upper liquid chamber and the lower liquid chamber; and a diaphragm disposed under the orifice plate inside the case, the diaphragm dividing the lower liquid chamber together with the orifice plate. The orifice plate has a direct passage for enabling the upper liquid chamber and the lower liquid chamber to directly communicate with each other so that liquid flows between the upper liquid chamber and the lower liquid chamber, and includes an opening/closing piston for opening or closing the direct passage.

Disclosed is an engine mount which includes a core installed in a case and supporting a load of an engine, an insulator mounted on the core and elastically deformed according to a load applied to the core, a diaphragm installed at a lower portion of the case, and an orifice assembly that divides a fluid-filled space between the insulator and the diaphragm into an upper liquid chamber and a lower liquid chamber and has at least one orifice for inducing a flow of fluid between the upper and lower liquid chambers, wherein the engine mount further includes a rubber membrane mounted between the orifice assembly and the insulator so as to be in close contact with a lower surface of the insulator, and wherein the orifice assembly includes a fluid transfer member for forcibly transferring a fluid, and operates according to driving conditions of a vehicle and selectively moves the fluid to the upper liquid chamber or the lower liquid chamber to regulate the liquid amount of the upper liquid chamber and the lower liquid chamber.

A partition member (17) of an anti-vibration device (1, 2, 3, 4) includes a membrane (31) and an orifice passage (21), the orifice passage includes a main liquid chamber-side passage (21a) and an auxiliary liquid chamber-side passage (21b), the main liquid chamber-side passage and the auxiliary liquid chamber-side passage extend in a circumferential direction and are disposed at mutually different radial positions, a flow direction in the main liquid chamber-side passage and a flow direction in the auxiliary liquid chamber-side passage are opposite to each other when liquid flows through the orifice passage, a channel cross-sectional shape in at least one passage of the main liquid chamber-side passage and the auxiliary liquid chamber-side passage is a laterally long flat shape that is short in an axial direction along a central axis (O) of a first attachment member and long in a radial direction, and a ratio of a radial size to an axial size in the one passage is larger than the ratio in the other passage of the main liquid chamber-side passage and the auxiliary liquid chamber-side passage.

A hydromount for mounting a motor vehicle unit is disclosed. The hydromount includes a supporting spring supporting a mount core and surrounding a working chamber, and a compensation chamber separated from the working chamber by a dividing wall and delimited by a compensation diaphragm. In embodiments, the compensation chamber and the working chamber are filled with a liquid and are connected by a damping duct incorporated into the dividing wall. In an embodiment, the dividing wall has two dividing plates between which a diaphragm is accommodated in a manner capable of oscillating. In an embodiment, the diaphragm and the dividing wall delimit an air chamber connected to the environment via an opening in the dividing wall, and the opening can be unblocked and closed by a switchable non-return device having a pressure-actuatable non-return valve with an opening pressure set to or having an oscillation amplitude of the diaphragm.

An anti-vibration device (1) of the present invention includes a cylindrical first attaching member (11) and a second attaching member (12), an elastic body (13), and a partition member (17) which is configured to partition a liquid chamber (14) in the first attaching member into a main liquid chamber (15) and an auxiliary liquid chamber (16). The partition member includes a membrane (31) that forms a part of the partition wall of the main liquid chamber, and an intermediate chamber (35) which is located on a side opposite to the main liquid chamber with the membrane therebetween and has a membrane as a part of a partition wall of the main liquid chamber. In the partition member, a first orifice (21) through which the main liquid chamber and the auxiliary liquid chamber communicate with each other, and a second orifice (22) through which the intermediate chamber and the auxiliary liquid chamber communicate with each other, and a common opening (16a) which forms an opening on the auxiliary liquid chamber side of each of the first orifice (21) and the second orifice (22) are formed.

A vibration-damping device (10) includes a tubular first attachment member (11) that is coupled to any one of a vibration-generating portion and a vibration-receiving portion; a second attachment member (12) that is coupled to the other one of the vibration-generating portion and the vibration-receiving portion; an elastic body (13) that couples both the attachment members (11 and 12) to each other; and a partition member (16) that divides a liquid chamber (19) inside the first attachment member (11) into a main liquid chamber (14) having the elastic body (13) as a part of a wall surface, and a sub-liquid chamber (15). A restriction passage (24) through which the main liquid chamber (14) and the sub-liquid chamber (15) communicate with each other is formed in the partition member (16). The partition member (16) is provided with a flow-speed restraint portion (32) which restrains a flow speed of liquid (L) flowing in the restriction passage (24). The flow-speed restraint portion (32) restrains a peak flow speed of the liquid (L) flowing into the main liquid chamber (14) from the restriction passage (24) to 10 m/sec or lower, when a liquid pressure in the main liquid chamber (14) is a negative pressure and a fluctuation rate of the liquid pressure within a predetermined time is 5% or lower.

According to the present invention, there is provided a vibration damping device (10) including a first bracket (11) and a second bracket (12), a first attachment member (14), a second attachment member (15), and an elastic body (16). The second attachment member (15) includes an insertion cylinder portion (22) in which the second bracket (12) is inserted. The insertion cylinder portion (22) is provided with a stopper portion (56) which faces a stopper wall (55) provided in the first bracket (11), in a radial direction (Y) in a side wall portion (57) oriented outward in the radial direction (Y) of the insertion cylinder portion (22). The stopper portion (56) includes a first stopper portion (61) and a second stopper portion (62) which are disposed in a manner of being displaced in an axial direction (X) of the insertion cylinder portion (22). The first stopper portion (61) is constituted by a first elastic portion (58). The second stopper portion (62) includes a rigid member (25). A first distance (D1) between the first stopper portion (61) and the stopper wall (55) in the radial direction (Y) is equal to or shorter than a second distance (D2) between the second stopper portion (62) and the stopper wall (55) in the radial direction (Y).