Liquid-sealing type vibration isolating apparatus

A liquid-sealing type vibration isolating apparatus comprising:

• a first coupling member attachable to a vibrator;
• a second coupling member attachable to a member on a vehicle body;
• an insulator interposed between the first coupling member and the second coupling member for absorbing and isolating vibration from the vibrator;
• a vibration isolating mechanism including:
• a main chamber having a chamber wall formed by one portion of the insulator and charged therein with liquid;
• an auxiliary chamber and a partition panel partitioned from the main chamber across a partition wall and communicating with the main chamber through an orifice;
• and
• a chamber wall portion formed by a first diaphragm, an air chamber partitioned from the auxiliary chamber across the diaphragm, and an equilibrium chamber partitioned from the main chamber across a second diaphragm;
• selector means for carrying out change-over operation so as to introduce negative pressure or the atmospheric pressure into the equilibrium chamber in the vibration isolating mechanism;
• control means for controlling the change-over operation of the selector means;
• a negative pressure tank having a predetermined volume arranged between a negative pressure source using intake negative pressure of an engine and the selector means;
• a check-valve provided between the negative pressure source and the negative pressure tank for introducing only negative pressure into the negative pressure tank;
• and
• drive means for operating a selector valve in the selector means, the drive means including a solenoid mechanism;
• wherein the partition wall is composed of a body portion having an outer peripheral portion formed therein with the orifice, the second diaphragm provided on the main chamber side of the body portion and defining the equilibrium chamber between itself and the body portion, and the partition panel arranged between the second diaphragm and the main chamber, defining a third liquid chamber between itself and the second diaphragm, and formed therein with a second orifice;
• and
• a cylindrical body fixture is joined to an outer periphery of the insulator, having a lower end portion extending downward, and a plurality of protrusions corresponding to a plurality of cut-out parts formed on an outer periphery of the partition wall, the partition wall is fitted and secured in the body fixture so that the protrusions are projected outward from the cut-out parts, and one of the protrusions is formed in a tubular shape so as to serve as a coupling portion for coupling the control means with an external drive means.

A liquid-sealing type vibration isolating apparatus comprising:

• a first coupling member attachable to a vibrator;
• a second coupling member attachable to a member on a vehicle body;
• an insulator interposed between the first coupling member and the second coupling member for absorbing and isolating vibration from the vibrator;
• a vibration isolating mechanism including:
• a main chamber having a chamber wall formed by one portion of the insulator and charged therein with liquid;
• an auxiliary chamber and a partition panel partitioned from the main chamber across a partition wall and communicating with the main chamber through an orifice;
• and
• a chamber wall portion formed by a first diaphragm, an air chamber partitioned from the auxiliary chamber across the diaphragm, and an equilibrium chamber partitioned from the main chamber across a second diaphragm;
• selector means for carrying out change-over operation so as to introduce negative pressure or the atmospheric pressure into the equilibrium chamber in the vibration isolating mechanism:
• control means for controlling the change-over operation of the selector means;
• a negative pressure tank having a predetermined volume arranged between a negative pressure source using intake negative pressure of an engine and the selector means;
• a check-valve provided between the negative pressure source and the negative pressure tank for introducing only negative pressure into the negative pressure tank;
• and
• drive means for operating a selector valve in the selector means, the drive means including a solenoid mechanism;
• wherein a negative pressure sub-tank is provided proximate to the selector means on a side remote from the equilibrium chamber, the sub-negative pressure tank having a volume which is equal to or larger than the sum of the volume of the equilibrium chamber and volume of a passage communicating between the equilibrium chamber and the selector means.

A liquid-sealing type vibration isolating apparatus comprising:

• a first coupling member attachable to a vibrator;
• a second coupling member attachable to a member on a vehicle body;
• an insulator interposed between the first coupling member and the second coupling member for absorbing and isolating vibration from the vibrator;
• a vibration isolating mechanism including:
• a main chamber having a chamber wall formed by one portion of the insulator and charged therein with liquid;
• an auxiliary chamber and a partition panel partitioned from the main chamber across a partition wall and communicating with the main chamber through an orifice;
• and
• a chamber wall portion formed by a first diaphragm, an air chamber partitioned from the auxiliary chamber across the diaphragm, and an equilibrium chamber partitioned from the main chamber across a second diaphragm;
• selector means for carrying out change-over operation so as to introduce negative pressure or the atmospheric pressure into the equilibrium chamber in the vibration isolating mechanism;
• control means for controlling the change-over operation of the selector means;
• a negative pressure tank having a predetermined volume arranged between a negative pressure source using intake negative pressure of an engine and the selector means;
• a check-valve provided between the negative pressure source and the negative pressure tank for introducing only negative pressure into the negative pressure tank;
• and
• drive means for operating a selector valve in the selector means, the drive means including a solenoid mechanism;
• wherein a solenoid constituting the selector means is operated in a direction having an angle of greater than 45 deg. with respect to a working axis of the liquid-sealing type vibration isolating apparatus.

A liquid-sealing type vibration isolating apparatus comprising:

• a first coupling member attachable to a vibrator;
• a second coupling member attachable to a member on a vehicle body;
• an insulator interposed between the first coupling member and the second coupling member for absorbing and isolating vibration from the vibrator;
• a vibration isolating mechanism including:
• a main chamber having a chamber wall formed by one portion of the insulator and charged therein with liquid;
• an auxiliary chamber and a partition panel partitioned from the main chamber across a partition wall and communicating with the main chamber through an orifice;
• a chamber wall portion formed by a first diaphragm, an air chamber partitioned from the auxiliary chamber across the diaphragm, and an equilibrium chamber partitioned from the main chamber across a second diaphragm;
• selector means for carrying out change-over operation so as to introduce negative pressure or the atmospheric pressure into the equilibrium chamber in the vibration isolating mechanism;
• control means for controlling the change-over operation of the selector means;
• a negative pressure tank having a predetermined volume arranged between a negative pressure source using intake negative pressure of an engine and the selector means;
• a check-valve provided between the negative pressure source and the negative pressure tank for introducing only negative pressure into the negative pressure tank;
• and
• drive means for operating a selector valve in the selector means, the drive means including a solenoid mechanism;
• wherein a passage for introducing an atmospheric pressure into the selector means for changing over the introduction of negative pressure and the atmospheric pressure has a cross-sectional area which is equal to or larger than that of a passage for introducing negative pressure into the selector means.

A liquid-sealing type vibration isolating apparatus comprising:

• a main chamber having a chamber wall formed of an insulator made of a rubber elastic material having a large wall thickness,
• an auxiliary chamber having a chamber wall formed by a portion of a first diaphragm formed of a rubber membrane having a small wall thickness and partitioned from the main chamber across a partition wall,
• a first orifice communicating between the main chamber and the auxiliary chamber, for reducing vibration having a predetermined low frequency under action of liquid flowing through the first orifice,
• a second diaphragm formed of an elastic membrane extending in the partition wall which is hollow,
• a third liquid chamber formed on the main chamber side of the second diaphragm,
• an equilibrium chamber formed on the auxiliary chamber side of the second diaphragm, for introducing thereinto negative pressure,
• a second orifice communicating between the third liquid chamber and the main chamber,
• selector means for carrying out a change-over operation so as to introduce negative pressure or the atmospheric pressure into the equilibrium chamber in the vibration isolating mechanism,
• control means for controlling the change-over operation of the selector means and being effective at a frequency which is higher than that at which the first orifice is effective, more than one of protrusions are formed on one of or both of the outer surface of the second diaphragm and the outer surface of the partition wall so as to define small spaces remaining between the second diaphragm and the partition wall when negative pressure is introduced in the equilibrium chamber;
• wherein the partition wall is composed of a body portion having an outer peripheral portion formed therein with the first orifice,
• the second diaphragm is provided on the main chamber side of the body portion and defines the equilibrium chamber between itself and the body portion, and
• a partition panel arranged between the second diaphragm and the main chamber, defining the third liquid chamber between itself and the second diaphragm, and formed therein with the second orifice.

A liquid-sealing type vibration isolating apparatus comprising:

• a main chamber having a chamber wall formed of an insulator made of a rubber elastic material having a large wall thickness,
• an auxiliary chamber having a chamber wall formed by a portion of a first diaphragm formed of a rubber membrane having a small wall thickness and partitioned from the main chamber across a partition wall,
• a first orifice communicating between the main chamber and the auxiliary chamber, for reducing vibration having a predetermined low frequency under action of liquid flowing through the first orifice,
• a second diaphragm formed of an elastic membrane extending in the partition wall which is hollow,
• a third liquid chamber formed on the main chamber side of the second diaphragm,
• an equilibrium chamber formed on the auxiliary chamber side of the second diaphragm, for introducing thereinto negative pressure,
• a second orifice communicating between the third liquid chamber and the main chamber,
• selector means for carrying out a change-over operation so as to introduce negative pressure or the atmospheric pressure into the equilibrium chamber in the vibration isolating mechanism, and
• control means for controlling the change-over operation of the selector means and being effective at a frequency which is higher than that at which the first orifice is effective, more than one of convex portions are formed on one of or both of the outer surface of the second diaphragm and the outer surface of the partition wall so as to define small spaces remaining between the second diaphragm and the partition wall when negative pressure is introduced in the equilibrium chamber,
• wherein a passage for introducing atmospheric pressure into the selector means for changing over the introduction of negative pressure and the atmospheric pressure has a cross-sectional area which is equal to or larger than that of a passage for introducing negative pressure into the selector means.

A liquid-sealing type vibration isolating apparatus comprising:

• a main chamber having a chamber wall formed of an insulator made of a rubber elastic material having a large wall thickness,
• an auxiliary chamber having a chamber wall formed by a portion of a first diaphragm formed of a rubber membrane having a small wall thickness and partitioned from the main chamber across a partition wall,
• a first orifice communicating between the main chamber and the auxiliary chamber, for reducing vibration having a predetermined low frequency under action of liquid flowing through the first orifice,
• a second diaphragm formed of an elastic membrane extending in the partition wall which is hollow,
• a third liquid chamber formed on the main chamber side of the second diaphragm,
• an equilibrium chamber formed on the auxiliary chamber side of the second diaphragm, for introducing thereinto negative pressure,
• a second orifice communicating between the third liquid chamber and the main chamber,
• selector means for carrying out a change-over operation so as to introduce negative pressure or the atmospheric pressure into the equilibrium chamber in the vibration isolating mechanism,
• control means for controlling the change-over operation of the selector means and being effective at a frequency which is higher than that at which the first orifice is effective, more than one of convex portions are formed on one of or both of the outer surface of the second diaphragm and the outer surface of the partition wall so as to define small spaces remaining between the second diaphragm and the partition wall when negative pressure is introduced in the equilibrium chamber,
• wherein a cylindrical body fixture is joined to an outer periphery of the insulator, having a lower end portion extending downward, and a plurality of protrusions corresponding to a plurality of cut-out parts are formed on an outer periphery of-the partition wall, the partition wall is fitted and secured in the body fixture so that the protrusions are projected outward from the cut-out parts, and one of the protrusions is formed in a tubular shape so as to serve as a coupling portion for coupling the control means with an external drive means.

A vibration isolating system comprising:

• two liquid-sealing type vibration isolating units provided on both sides of a vibrator, and each composed of:
• an upper coupling member attached to the vibrator,
• a lower coupling member attached to a member in a vehicle body,
• an insulator interposed between the upper and lower coupling members, for absorbing and isolating vibration from the vibrator,
• a main chamber having a chamber wall formed from a portion of the insulator and charged therein with liquid,
• an auxiliary chamber communicating with the main chamber through an orifice and having a wall chamber a portion of which is formed by a first diaphragm,
• an air chamber partitioned from the auxiliary chamber across the first diaphragm, and
• an equilibrium chamber partitioned from the main chamber across a second diaphragm;
• selector means communicating with the equilibrium chambers in the two liquid-sealing type vibration isolating units, for carrying out a change-over operation so as to continuously introduce either one of negative pressure and atmospheric pressure into the equilibrium chambers, respectively, or to alternately introduce the negative pressure or the atmospheric pressure into the equilibrium chamber, the selector means being connected with one of the equilibrium chamber so as to transmit pressure variation in synchronized frequency with engine vibration, and being connected with the other one of the equilibrium chambers by way of a changing means for changing at least one of a phase and an amplitude;
• and
• control means for controlling the changeover operation of the selector means;
• wherein said changing means is a phase changing means, and
• said phase changing means is composed of an expansion chamber provided in a passage communicating between the selector means and one of the equilibrium chambers and having a predetermined volume, a diaphragm provided in the expansion chamber, and a mass provided to the diaphragm and having a predetermined mass weight.

A vibration isolating system comprising:

• two liquid-sealing type vibration isolating units provided on both sides of a vibrator, and each composed of:
• an upper coupling member attached to the vibrator,
• a lower coupling member attached to a member in a vehicle body,
• an insulator interposed between the upper and lower coupling members, for absorbing and isolating vibration from the vibrator,
• a main chamber having a chamber wall formed from a portion of the insulator and charged therein with liquid,
• an auxiliary chamber communicating with the main chamber through an orifice and having a wall chamber a portion of which is formed by a first diaphragm,
• an air chamber partitioned from the auxiliary chamber across the first diaphragm, and
• an equilibrium chamber partitioned from the main chamber across a second diaphragm;
• selector means communicating with the equilibrium chambers in the two liquid-sealing type vibration isolating units, for carrying out a change-over operation so as to continuously introduce either one of negative pressure and atmospheric pressure into the equilibrium chambers, respectively, or to alternately introduce the negative pressure or the atmospheric pressure into the equilibrium chamber, the selector means being connected with one of the equilibrium chamber so as to transmit pressure variation in synchronized frequency with engine vibration, and being connected with the other one of the equilibrium chambers by way of a changing means for changing at least one of a phase and an amplitude;
• and
• control means for controlling the changeover operation of the selector means;
• wherein the other one of said vibration isolating units is connected through a passage which is formed so that pressure variation is not transmitted thereto with a synchronized frequency with the engine vibration.