INVERTED ACTIVE HYDRO BEARING

Description

[0001] The present invention relates to an active hydraulic bearing, in particular an inverted active hydraulic bearing, according to the preamble of claim 1, an engine with such a hydraulic bearing according to claim 9, and a motor vehicle with such an engine according to claim 10.

[0002] Various types and designs of bearings are known for isolating vibrations. These include so-called hydraulic mounts. They serve to elastically support assemblies, particularly vehicle engines. Such hydraulic mounts, for example, positioned between an engine and a vehicle chassis, are intended to prevent engine vibrations from being transmitted to the vehicle frame. The well-known conflict in vibration isolation must be considered here: the bearing should be as stiff as possible to withstand high loads and bearing forces, while simultaneously exhibiting a soft characteristic to effectively isolate vibrations across a wide frequency range.

[0003] In a hydraulic mount, a fluid, such as hydraulic fluid, can be moved back and forth between a working chamber and a compensating chamber via a throttle channel. A throttle unit separates the fluid volume between the working chamber and the compensating chamber, forming the throttle channel that connects them. Since the throttle channel presents a flow resistance, vibrations acting on the working chamber via a spring element (usually an elastomeric element) can be dampened by the fluid movement through the throttle channel. Vibrations up to approximately 5 Hz are absorbed by the relatively high stiffness of the spring element. Low-frequency vibrations, typically between 5 Hz and 20 Hz, are dampened by the interaction of the two hydraulic chambers via the throttle channel.

[0004] Several types of hydraulic mounts can be distinguished: So-called conventional hydraulic mounts have the previously described structure and associated mode of operation, in which the inner side of the elastic spring and one side of the throttle unit typically form the working chamber, while an elastic rolling diaphragm and the opposite side of the throttle unit form the equalization chamber. The elastic rolling diaphragm creates a variable volume in the equalization chamber, allowing the usually incompressible fluid to escape from the working chamber. Alternatively or additionally, an elastic decoupling diaphragm may be present, which enables elastic pressure equalization between the two hydraulic chambers. Apart from the elasticity of the spring, the rolling diaphragm, and / or the decoupling diaphragm, conventional hydraulic mounts typically do not contain any moving parts.

[0005] So-called switchable hydraulic mounts have essentially the same design and operating principle as conventional hydraulic mounts. In addition to the throttle channel, however, switchable hydraulic mounts have a bypass channel whose flow can be opened and closed. Alternatively, a channel for venting an air chamber below the decoupling membrane can also be opened and closed. In both cases, opening or closing the respective channel allows for the selection of two different stiffness and damping characteristics of the mount, enabling it to be switched between "soft" and "hard" settings. In other words, a different stiffness of the switchable hydraulic mount can be set in certain situations compared to normal operation. This switching function can be performed by an electromagnetic actuator.

[0006] So-called controllable or active hydraulic mounts are fundamentally similar in design and function to conventional hydraulic mounts, but feature a controllable mechanism for continuously varying the volume of the working chamber. This allows for active manipulation of the hydraulic mount's isolation characteristics. Controllability is typically achieved via a linear electromagnetic actuator, which moves a control diaphragm relative to the working chamber, for example, via a piston. The control diaphragm forms part of the working chamber wall, allowing the hydraulic volume of the chamber to be altered by its movement. By activating the actuator and thus acting upon the control diaphragm, a reduction in the dynamic spring rate of the hydraulic mount can be achieved in the high-frequency vibration range.

[0007] Controllable or active hydraulic mounts can be divided into conventional controllable hydraulic mounts and inverted controllable hydraulic mounts. In conventional controllable hydraulic mounts, the fluid presses directly onto the diaphragm facing the working chamber, i.e., usually from above, from the side of the spring. In inverted controllable hydraulic mounts, the diaphragm presses onto the diaphragm from the side of the compensation chamber or the side of the throttle channel, i.e., usually from below, from the side of the actuator. In this case, there is typically a closed air volume behind the diaphragm, which is completely isolated from the surrounding environment.

[0008] All previously described types of hydraulic mounts can be used as engine mounts.

[0009] Controllable or active hydraulic mounts have in common that the actuator is always located outside the fluid chambers, i.e., outside the working chamber and outside the compensation chamber. The actuator is usually positioned below the hydraulic mount, i.e., below the compensation chamber.

[0010] A disadvantage here is that additional vertical installation space is required for the actuator and its connection. This required vertical installation space is particularly large with an inverted active hydraulic bearing due to the inherent design, as space is needed for the flow geometry, the air chamber, and a seal.

[0011] A further disadvantage is that the actuator plunger penetrates the chamber due to the inverted connection of the control diaphragm. Therefore, a seal must be created between the actuator plunger and the working chamber. This seal must withstand the high pressure in the working chamber and be dimensioned accordingly. Since the seal must be located between the actuator and the control diaphragm, a correspondingly large distance between the two components is required, which directly affects the required installation space in the vertical direction.

[0012] A further disadvantage is that insufficient dimensioning or aging or fatigue of the sealing point between actuator and control membrane can lead to leaks and thus to a deterioration of the bearing properties.

[0013] A further disadvantage is the high additional mass of the separate actuator plunger and guide pin. Besides the higher costs and more complex assembly, the increased weight also significantly influences the resonant frequency of the actuator coupled to the bearing. In this case, a low natural frequency directly leads to deteriorated high-frequency bearing performance.

[0014] Another disadvantage is that additional installation space is required for the formation of the air chamber in the inverted active engine mount.

[0015] JP 2007 231973 A describes a vibration damping device with a magnetic area on the central side of a second diaphragm, which forms part of a partition of a second partial liquid chamber, and with a non-magnetic elastic area on an outer circumferential side of the magnetic area. The elastic area is elastically deformed to make the second diaphragm deformable in the direction of expansion of the second partial liquid chamber. Thus, when an electromagnet exerts an electromagnetic attraction on the magnetic area of ​​the second diaphragm while shaking vibrations are initiated, the deformation of the second diaphragm along the direction of expansion is restricted. When the electromagnet no longer exerts the electromagnetic attraction on the second diaphragm during the initiation of the idle vibration, the second diaphragm is deformable along the direction of expansion.

[0016] EP 0 561 703 A1 describes a hydraulic anti-vibration support with a rigid frame, a head, a frustoconical elastomeric wall connecting the cylinder to the head, a diaphragm supported by the cylinder, a partition separating the interior of the resulting fluid-filled housing into a working chamber and a compensating chamber, a throttled passage connecting the two chambers, a small-displacement piston, and an electrical exciter capable of generating counter-vibrations in the piston. An air-filled capsule, bounded by the piston and a rigid wall attached to the frame by a slotted spacer, is immersed in the working chamber, with the piston positioned between the wall and the exciter, and the circumference of the piston connected to the wall by a sealed and deformable annular seal.

[0017] DE 100 19 872 A1 describes a flexible body that connects first and second fastening elements, which partially define a fluid chamber filled with a non-compressible fluid. A vibrating element partially defines the fluid chamber. An electromagnetic actuator sets the vibrating element into vibration to control the pressure of the non-compressible fluid. A stabilizing element, attached to one of the opposite sides of the vibrating element, is offset from it.

[0018] German patent DE 10 2007 014 242 B4 describes a motor mount with hydraulically active damping. A working chamber is surrounded by an elastic circumferential wall and a compensation chamber. A compensation plate is designed as a flexible support membrane. A conventional piezoelectric flat actuator is combined with the flexible support membrane in a material bond to form an active flexible compensation membrane via a connecting surface.

[0019] One object of the present invention is to provide an active hydraulic bearing, in particular an inverted active hydraulic bearing, of the type described above, with a reduced vertical installation space. Additionally or alternatively, the risk of leaks in an active hydraulic bearing, in particular an inverted active hydraulic bearing, of the type described above, is to be reduced. Additionally or alternatively, the weight, in particular the weight of the moving components, in an active hydraulic bearing, in particular an inverted active hydraulic bearing, of the type described above, is to be reduced.

[0020] The object of the invention is achieved by an active hydraulic bearing, in particular by an inverted active hydraulic bearing, with the features of claim 1, by a motor with the features of claim 9, and by a motor vehicle with the features of claim 10. Advantageous embodiments are described in the dependent claims.

[0021] The present invention therefore relates to an active hydraulic bearing, in particular an inverted active hydraulic bearing. The hydraulic bearing comprises a first fluid chamber, a second fluid chamber, and a throttle channel which can connect the first fluid chamber and the second fluid chamber in a fluid-flowing manner. Preferably, an incompressible hydraulic fluid can be used as the fluid, as is common in hydraulic bearings.

[0022] The active hydraulic mount further comprises a flow-through volume, which is designed to be connected to the first fluid chamber via fluid flow, and an actuator with a control diaphragm, wherein the actuator is designed to be able to move the control diaphragm relative to the flow-through volume, in particular translationally. By moving the control diaphragm against the fluid located in the flow-through volume, the fluid in the first fluid chamber can be actively influenced, in accordance with the function of an active hydraulic mount.

[0023] The actuator is arranged between the first fluid chamber and the second fluid chamber. In other words, according to the invention, the actuator can be arranged within the fluid chambers. In this way, the active hydraulic bearing can be designed more compactly, i.e., with less installation space. In particular, a significant reduction in the installation space of an (inverted) active hydraulic bearing can be achieved in the vertical direction.

[0024] According to the invention, the actuator is arranged between the first fluid chamber and the surrounding flow volume. This allows for a particularly compact arrangement, especially in the vertical direction, of the individual elements or fluid chambers of an inverted active hydraulic bearing. In particular, this enables the actuator and the control diaphragm to act vertically downwards towards the surrounding flow volume and thus away from the first fluid chamber, as is typical of the operating principle of an inverted active hydraulic bearing.

[0025] According to a further aspect of the present invention, the first fluid chamber and / or the second fluid chamber are arranged essentially parallel to the flow volume. In other words, the first fluid chamber and / or the second fluid chamber, as well as the flow volume, extend essentially in a horizontal plane perpendicular to the vertical direction of the active hydraulic bearing. This allows for a compact design in the vertical direction.

[0026] According to a further aspect of the present invention, the active hydraulic mount also has a flow channel configured to connect the flow volume and the first fluid chamber via fluid flow. In this way, a defined fluid-carrying connection between the flow volume and the first fluid chamber can be established. The design of the flow channel can also be used to selectively influence the damping behavior of the active hydraulic mount. Furthermore, the flow channel can be configured to establish a defined fluid-carrying connection between the flow volume and the first fluid chamber, even in the arrangement of the actuator relative to the fluid chambers according to the invention.

[0027] According to a further aspect of the present invention, the throttle channel and the flow channel are arranged essentially parallel to each other. In this way, for both rectangular and cylindrical configurations of an active hydraulic bearing according to the invention, a fluid-carrying connection can be implemented between the throttle channel and the first and second fluid chambers on one side of the active hydraulic bearing, and between the flow channel and the flow volume. This can be easily achieved by clearly separating the throttle channel and the flow channel. Furthermore, different configurations of the throttle channel and the flow channel can preferably be used independently of each other and combined with one another, thus enabling a modular design of the active hydraulic bearing.

[0028] According to a further aspect of the present invention, the throttle channel and / or the flow channel are essentially meander-shaped. This allows for a compact design of the throttle channel and / or the flow channel, while simultaneously enabling a certain length of the respective channel, which can affect the flow resistance of the channel. This provides additional possibilities, besides, for example, the cross-section of a channel, for selectively influencing the flow behavior of the fluid through the respective channel.

[0029] According to a further aspect of the present invention, the throttle channel and / or the flow channel are arranged essentially perpendicular to the first fluid chamber and / or the second fluid chamber and / or the flow volume. This can promote a compact design in the horizontal plane perpendicular to the vertical direction of the active hydraulic bearing, which can be particularly advantageous when combined with a compact design in the vertical direction itself, in order to create an overall compact active hydraulic bearing.

[0030] According to a further aspect of the present invention, the control diaphragm borders the flow volume on one side and an air chamber on the opposite side. This eliminates the need for an additional air chamber and a vent hole, because the air chamber can be arranged with the actuator, or as a component of the actuator, between the first fluid chamber and the second fluid chamber.

[0031] According to a further aspect of the present invention, the air chamber is arranged at least substantially, preferably completely, within the installation space of the actuator, preferably between the throttle channel, the flow channel, the first fluid chamber, and the flow volume. This allows the air chamber to be designed or arranged in a space-saving manner around the actuator, as a component of the actuator, or through the installation space of the active hydraulic mount provided for receiving the actuator, which can promote a compact design of the active hydraulic mount.

[0032] According to the invention, the control diaphragm has a shaft that can be moved translationally by the actuator. The shaft can simultaneously be used to guide the actuator components, thus eliminating the need for an additional guide pin. This eliminates one component compared to known (inverted) active hydraulic bearings, which can reduce both the weight of the actuator's moving components and the actuator's overall volume. This weight reduction can lead to an increase in actuator-bearing resonance and thus to improved active bearing performance in the high-frequency range. Overall, the actuator's design and the implementation of the (translational) movement of the control diaphragm can be simplified.

[0033] According to the invention, the control diaphragm has a flange which is fixedly connected to the shaft and elastically connected to the actuator. This allows a movable connection between the flange and the actuator to be created via the shaft, whereby movement between the actuator coils and the shaft can be enabled electromagnetically. Simultaneously, a fluid-tight connection can be created because the actuator coils and the shaft can be arranged within the flange with its elastic coupling to the fixed components of the actuator. In other words, (translational) movement of the control diaphragm can occur from the rear, from the perspective of the surrounding flow volume. In this way, seals between the actuator plunger and the surrounding flow volume can be dispensed with, because, according to the invention, the surrounding flow volume does not need to be penetrated by the actuator plunger at all to enable the movement of the actuator.to transfer the actuator plunger to the control diaphragm. This avoids sealing problems at this point. It also eliminates the need for a seal. This can also simplify the design of the rolling diaphragm.

[0034] According to the invention, the first fluid chamber is a working chamber and the second fluid chamber is a compensation chamber. This allows the inventive effect to be exerted between the working chamber and the compensation chamber of the hydraulic bearing.

[0035] The present invention also relates to an engine with a hydraulic bearing as described above.

[0036] The present invention also relates to a motor vehicle with an engine as described above.

[0037] Two exemplary embodiments and further advantages of the invention are explained below in connection with the following figures. These show: Fig. 1 a schematic sectional view of an inverted active hydraulic bearing according to the prior art; Fig. 2a a schematic sectional view of an inverted active hydraulic bearing according to a first embodiment of the present invention; Fig. 2 a detailed view of the Fig. 2a ; Fig. 3a a throttle unit for use with the inverted active hydraulic bearing of the Fig. 2a ; Fig. 3 schematic sectional view of the throttle unit of the Fig. 3a ; Fig. 4 a schematic sectional view of an inverted active hydraulic bearing according to a second embodiment of the present invention; and Fig. 5 a throttle unit for use with the inverted active hydraulic bearing of the Fig. 4 .

[0038] Fig. 1 Figure 1 shows a schematic sectional view of an inverted active hydraulic mount 1 according to the prior art. The outer surface of the hydraulic mount 1 is formed at the top by a bearing housing 10 and at the bottom by a bearing cover 11. An elastomeric support element 12 in the form of an elastomeric spring 12 is arranged in the bearing housing 10, projecting upwards from the bearing cover 11 with its tension / compression stop 13. For example, a motor vehicle engine can be mounted on the tension / compression stop 13, and its vibrations are to be dampened or isolated by the hydraulic mount 1. A rolling diaphragm 14 is arranged inside the lower bearing cover 11.

[0039] Approximately at its midpoint, a throttle unit 21 is arranged within the hydraulic mount 1. The upper side of the throttle unit 21 and the inner side of the elastomeric support spring 12 form a first fluid chamber 20, which serves as the working chamber 20 of the hydraulic mount 1. The lower side of the throttle unit 21 and the inner side of the rolling diaphragm 14 form a second fluid chamber 25, which serves as the compensation chamber 25 of the hydraulic mount 1. A throttle channel 22 is formed within the throttle unit 21, which runs essentially horizontally and in an annular shape. The throttle channel 22 has a throttle channel inlet 23 towards the working chamber 20 and a throttle channel outlet 24 towards the compensation chamber 25.

[0040] The throttle channel 21 connects the working chamber 20 and the compensation chamber 25 via fluid flow, allowing a fluid such as hydraulic fluid to be exchanged between the working chamber 20 and the compensation chamber 25 through the throttle channel 22. The flow resistance that the throttle channel 22 presents to the fluid influences the damping and isolation behavior of the hydraulic mount 1.

[0041] Due to its function as an active hydraulic bearing 1, the hydraulic bearing 1 has an electromagnetic linear actuator 35 in the bearing cover 11, which is arranged within the rolling diaphragm 14 that runs ring-shaped around the electromagnetic linear actuator 35. The electromagnetic linear actuator 35 can move an actuator plunger 34 up and down in the vertical direction X. The actuator plunger 34 is circular and disc-shaped at its upper end. The lateral edges of the actuator plunger 34 are elastically connected to an upper throttle disk 31 via a control diaphragm 30, so that an air chamber 33 is formed between the underside of the upper throttle disk 31 and the upper side of the actuator plunger 34 and the control diaphragm 30, forming a closed air volume. A flow volume 26 is formed between the lower throttle disk 32 and the control diaphragm 30, which is fluid-carrying and connected to the working chamber 20 via an inlet 27.The control membrane 30 can act on the fluid within the flow volume 26 via the movement of the linear actuator 35 in the vertical direction X (on this fluid) and thus also on the fluid within the working chamber 20. This makes the present hydraulic bearing 1 an inverted active hydraulic bearing 1.

[0042] The part of the throttle unit 21 which has the throttle channel 22 can be referred to as the lower throttle disk 32, with the throttle channel inlet 23 passing through the upper throttle disk 31. The throttle channel 22 runs in a ring or spiral shape around the linear actuator 35 or around the control diaphragm 30.

[0043] Such an inverted active hydraulic bearing 1 has a comparatively large extent in the vertical direction X, so that at least in the vertical direction X a comparatively large installation space is required to use such an inverted active hydraulic bearing 1 in a vehicle.

[0044] Fig. 2a Figure 1 shows a schematic sectional view of an inverted active hydraulic bearing 1 according to a first embodiment of the present invention. Fig. 2b shows a detailed view of the Fig. 2a . Fig. 3a shows a throttle unit 21 for use with the inverted active hydraulic bearing 1 of the Fig. 2a . Fig. 3b shows a schematic sectional view of the throttle unit of the Fig. 3a .

[0045] In the inverted active hydraulic bearing 1 according to the first embodiment of the present invention, the linear actuator 35 is arranged in the vertical direction X between the working chamber 20 and the compensation chamber 25. In this way, a more compact design than previously known can be created.

[0046] For this purpose, the flow volume 26 is arranged below the linear actuator 35, and is further formed essentially by the lower throttle disk 32 and the control diaphragm 30. The fluid-carrying connection between the flow volume 26 is formed laterally to the left of the linear actuator 35 by a substantially vertical flow channel 29, the inlet 27 of which connects the flow channel 29 to the working chamber 20 and the outlet 28 of which connects the flow channel 29 to the compensation chamber 25. This allows a fluid-carrying connection between the working chamber 20 and the flow volume 26 to be created in the arrangement of the linear actuator 35 according to the invention.

[0047] The control diaphragm 30 is essentially formed by a flange 37, which is fixedly connected to a shaft 36 and elastically connected to the linear actuator 35. The shaft 36 of the linear actuator 35 of the inverted active hydraulic bearing 1 according to the first embodiment of the present invention corresponds to the actuator plunger 34 of such a known inverted active hydraulic bearing 1, wherein the shaft 36 or the control diaphragm 30 has a simpler design. This saves in effort and installation space. Furthermore, seals of the actuator plunger 34 against the flow volume 26 can be omitted because the shaft 36 of the linear actuator 35 of the inverted active hydraulic bearing 1 according to the first embodiment of the present invention is arranged behind the control diaphragm 30 and does not penetrate it at all.

[0048] The inverted active hydraulic bearing 1 according to the first embodiment of the present invention is rectangular. The flow channel 29 is arranged to the left of the linear actuator 35, next to it. However, since this prevents a continuous ring-shaped or spiral course of the throttle channel 22 around the linear actuator 35, the throttle channel unit 21 is arranged to the right of the linear actuator 35. The throttle channel inlet 23 connects the throttle channel 22 upwards in the vertical direction X to the working chamber 20. The throttle channel outlet 24 connects the throttle channel 22 downwards in the vertical direction X to the compensation chamber 25. The throttle channel 22 is arranged in a meandering pattern within the throttle channel unit 21, cf. Fig. 3a und 3b This allows the fluid-carrying connection of the throttle channel 22 to be implemented even in the arrangement of the linear actuator 35 according to the invention.

[0049] Fig. 4 Figure 1 shows a schematic sectional view of an inverted active hydraulic bearing 1 according to a second embodiment of the present invention. Fig. 5 shows a throttle unit 21 for use with the inverted active hydraulic bearing of the Fig. 4 .

[0050] The inverted active hydraulic bearing 1 according to a second embodiment of the present invention has a linear actuator 35, which is cylindrical in shape. Accordingly, the throttle unit 21 is semi-shell shaped, cf. Fig. 5 . Reference symbol list (part of the description)

[0051] X-vertical direction 1 (inverted) active hydraulic bearing 10 Bearing housing 11 Bearing cover 12 Elastomeric support body or elastomeric support spring 13 Tension / compression stop of the support body 12 14 Rolling diaphragm of the compensation chamber 25 20 First fluid chamber; working chamber 21 Throttle unit 22 Throttle channel 23 Throttle channel inlet 24 Throttle channel outlet 25 Second fluid chamber; equalization chamber 26 Flow volume; flow geometry 27 Flow channel inlet 29 or flow volume 26 28 Flow channel outlet 29 29 Flow channel 30 Control diaphragm 31 Upper throttle disc 32 Lower throttle disc 33 Air chamber 34 Actuator plunger; actuator guide pin 35 35 Actuator; (electromagnetic) linear actuator 36 Actuator plunger shaft 34 37 Actuator plunger flange 34

Claims

1. Active hydraulic mount (1), in particular inverted active hydraulic mount (1), having a first fluid chamber (20), a second fluid chamber (25), a throttle channel (22), which is configured to connect the first fluid chamber (20) and the second fluid chamber (25) to one another in terms of fluid flow, a bypass volume (26), which is configured to be connected in terms of fluid flow to the first fluid chamber (20), and an actuator (35) with a control diaphragm (30), wherein the actuator (35) is configured to be able to move the control diaphragm (30), in particular in a translational manner, relative to the bypass volume (26), the first fluid chamber (20) is a working chamber (20) and the second fluid chamber (25) is a compensation chamber (25), characterized in that the actuator (35) is arranged between the first fluid chamber (20) and the second fluid chamber (25), the actuator (35) is arranged between the first fluid chamber (20) and the bypass volume (26), the control diaphragm (30) has a shaft (36) which can be moved in a translational manner by the actuator (35), the control diaphragm (30) has a flange (37) which is connected fixedly to the shaft (36) and elastically to the actuator (35).

2. Active hydraulic mount (1) according to Claim 1, wherein the first fluid chamber (20) and / or the second fluid chamber (25) are / is arranged substantially parallel to the bypass volume (26).

3. Active hydraulic mount (1) according to Claim 1 or 2, furthermore having a bypass channel (29), which is configured to connect the bypass volume (26) and the first fluid chamber (20) to one another in terms of fluid flow.

4. Active hydraulic mount (1) according to Claim 3, wherein the throttle channel (22) and the bypass channel (29) are arranged substantially parallel to one another.

5. Active hydraulic mount (1) according to Claim 4, wherein the throttle channel (22) and / or the bypass channel (29) are / is of substantially meandering form.

6. Active hydraulic mount (1) according to one of the preceding claims, wherein the throttle channel (22) and / or the bypass channel (29) are / is arranged substantially perpendicularly to the first fluid chamber (20) and / or to the second fluid chamber (25) and / or to the bypass volume (26).

7. Active hydraulic mount (1) according to one of the preceding claims, wherein the control diaphragm (30) is at one side adjacent to the bypass volume (26) and at the opposite side adjacent to an air chamber (33).

8. Active hydraulic mount (1) according to Claim 7, wherein the air chamber (33) is arranged at least substantially, preferably completely, within the installation space of the actuator (35), preferably between the throttle channel (22), the bypass channel (29), the first fluid chamber (20) and the bypass volume (26).

9. Engine having an active hydraulic mount (1), in particular having an inverted active hydraulic mount (1), according to one of the preceding claims.

10. Motor vehicle having an engine according to Claim 9.