Multi-stage switchable inertia track assembly

摘要

A two vacuum actuated switch mechanism is provided within an engine or hydromount. First and second ports are provided along a peripheral portion of an inertia track assembly. A decoupler or vacuum diaphragm is selectively exposed to vacuum through a first port. Under the influence of the vacuum, the decoupler can no longer oscillate. If vacuum is applied only to the decoupler, and not and idle diaphragm, the fluid is forced through a low frequency inertia track which creates high levels of damping and low frequencies. If vacuum is also applied to the decoupler and the idle diaphragm, the high frequency inertia track is opened and causes the fluid to flow therethrough. This creates a high frequency dynamic rate dip. Alternatively, if no vacuum is applied to either the decoupler or the idle diaphragm, the decoupler is allowed to freely oscillate creating a decoupled state for low input displacements. Higher input displacements results in fluids being forced through the low frequency inertia track. An integrated accumulator is disposed between the port and the decoupler to reduce or eliminate air resonance response, buffering the pumping effect of the decoupler in a decoupled state.

主权项

1. A multistage switchable inertia track assembly comprising:
a housing; an inertia track received in the housing and having an elongated fluid damped first path that is adapted to communicate with an associated first fluid chamber on a first side and an associated second fluid chamber on a second side, and a second path that communicates with the associated first and second fluid chambers, the first side of the inertia track forming a portion of the first fluid chamber, and the second side of the inertia track forming a portion of the second fluid chamber; a decoupler received in the housing between the first and second fluid chambers; an idle diaphragm in the housing that has a first surface that forms a part of the second fluid chamber and selectively controls communication between the first and second fluid chambers to selectively alter the damping; and first and second ports in the inertia track that separately communicate with the decoupler and with a second surface of the idle diaphragm, respectively, the first and second ports configured to be selectively connected to vacuum or no vacuum such that the assembly is configured to be operated in four modes, comprising: in a first mode the first and second ports are connected to vacuum so that the decoupler no longer oscillates and the idle diaphragm opens the second path through the inertia track, in a second mode no vacuum is applied to either the first port or the second port so that the decoupler freely oscillates and the idle diaphragm closes the second path through the inertia track whereby fluid must flow from the first chamber to the second chamber through the first path, in a third mode vacuum is applied to the first port only and not to the second port so that the idle diaphragm closes the second path through the inertia track and fluid from the first chamber to the second chamber must pass through the first path, and in a fourth mode vacuum is applied to the second port only and not to the first port so that the decoupler oscillates freely for a first predetermined displacement input but fluid will flow through the open second path through the inertia track.