Noise reduction apparatus and method

Claim 2

A throttle control device for varying the quantity of fuel fed to an engine in a vehicle at each instant in response to variations in the pressure and volume of a hydraulic fluid discharged from a pump means driven by the engine to maintain the engine at speeds approaching idling, comprising: auxiliary means for providing a cyclic operation distinct from the movement of the vehicle where the auxiliary means imposes variable magnitudes of load at different times in each cycle, the auxiliary means being operatively coupled to the pump means to provide for the discharge of the hydraulic fluid from the pump means at each instant in accordance with the magnitude of the variable load from the auxiliary means at that instant; first receiving means for receiving at each instant characteristics proportional the volume of hydraulic fluid discharged by the pump means to the auxiliary means at that instant; second receiving means for receiving at each instant characteristics proportional to the pressure of hydraulic fluid discharged by the pump means to the auxiliary means at that instant; and biasing means, control means actuatable, against the action of the biasing means, by the cumulative effect of the first and second receiving means at each instant in accordance with the pressure and the volume of the hydraulic fluid respectively introduced to the first and second receiving means to transmit movement to the engine throttle in a direction to change the speed of the engine in a direction corresponding to variations in the cumulative effect of the pressure and flow of the fluid discharged by the pump means and thereby maintain the engine at a speed approaching idling with the degree of movement of the engine throttle being dependent on the cumulative effect of both the pressure and volume of fluid discharged by the pump means, whereby the torque output of the engine is varied at the engine speeds approaching idling in response to the load requirements imposed upon the pump by the auxiliary means.

Claim 3

The throttle control device of claim 1, including: a movable piston having first and second differential pressure receiving areas, with the first one of said areas being constructed to receive a pressure dependent upon the output pressure of the hydraulic fluid discharged by the pump means to the auxiliary means and the second one of said areas being constructed to receive a pressure proportional to the volume of the hydraulic fluid discharged by the pump means to the auxiliary means, and said piston being operably connected to the control means to transmit movement to the control means, against the action of the biasing means, in accordance with the cumulative effect of the volume and pressure of the hydraulic fluid discharged by the pump means to the auxiliary means.

Claim 4

The throttle control device of claim 2 wherein the biasing means constitute spring means resiliently biasing said piston in a first direction and imposing a resistive force against movement of said piston in a direction operAting upon said control means to throttle the engine throttle.

Claim 5

The throttle control device of claim 1, including: adjustable stop means to limit the degree of movement transmitted to the engine throttle.

Claim 6

A throttle control device for varying the quantity of fuel fed to an engine in a vehicle at each instant in response to variations in the pressure and volume of a hydraulic fluid discharged from a pump means driven by the engine to maintain the engine at speeds approaching idling, comprising: auxiliary means for providing a cyclic operation distinct from the movement of the vehicle where the auxiliary means imposes variable magnitudes of load at different times in each cycle, the auxiliary means being operatively coupled to the pump means to provide for the discharge of the hydraulic fluid from the pump means at each instant in accordance with the magnitude of the variable load from the auxiliary means at that instant; first receiving means for receiving at each instant characteristics proportional to the volume of hydraulic fluid discharged by the pump means to the auxiliary means at that instant; second receiving means for receiving at each instant characteristics proportional to the pressure of hydraulic fluid discharged by the pump means to the auxiliary means at that instant; control means actuatable by the first and second receiving means at each instant in accordance with the pressure and the volume of the hydraulic fluid respectively introduced to the first and second receiving means to transmit movement to the engine throttle in a direction to maintain the engine at a speed approaching idling with the degree of movement being dependent on both the pressure and volume of fluid discharged by the pump, whereby the torque output of the engine is varied at the engine speeds approaching idling in response to the load requirements imposed upon the pump by the auxiliary means, wherein the biasing means constitute spring means resiliently biasing said piston in a first direction and imposing a resistive force against movement of said piston in a direction operating upon said control means to throttle the engine throttle, and the spring means and the piston being positioned relative to each other to define a gap when the piston is biased in the first direction, whereby the initial movement of the piston in response to pressure from the hydraulic fluid discharged from the pump to the auxiliary means is relatively rapid to provide a quick initial response of the control means when the auxiliary means begins its cyclic operation.

Claim 7

A throttle control device for varying the quantity of fuel fed to an engine in a vehicle at each instant in response to variations in the pressure and volume of a hydraulic fluid discharged from a pump means driven by the engine to maintain the engine at speeds approaching idling, comprising: auxiliary means for providing a cyclic operation distinct from the movement of the vehicle where the auxiliary means imposes variable magnitudes of load at different times in each cycle, the auxiliary means being operatively coupled to the pump means to provide for the discharge of the hydraulic fluid from the pump means at each instant in accordance with the magnitude of the variable load from the auxiliary means at that instant; first receiving means for receiving at each instant characteristics proportional to the volume of hydraulic fluid discharged by the pump means to the auxiliary means at that instant; second receiving means for receiving at each instant characteristics proportional to the pressure of hydraulic fluid discharged by the pump means to the auxiliary means at that instant; control means actuatable by the first and second receiving means at each instant in accordance with the pressure and the volume of the hydraulic fluid respectively introduced to the first and second receiving means to transmit movement to the engine throttle in a direction to maintain the engine at a speed approaching idling with the degree of movement being dependent on both the pressure and volume of fluid discharged by the pump, whereby the torque output of the engine is varied at the engine speeds approaching idling in response to the load requirements imposed upon the pump by the auxiliary means, wherein the biasing means constitute spring means resiliently biasing said piston in a first direction and imposing a resistive force against movement of said piston in a direction operating upon said control means to throttle the engine throttle, and the spring means and the piston being positioned relative to each other to define a gap when the piston is biased in the first direction, whereby the initial movement of the piston in response to pressure from the hydraulic fluid discharged from the pump to the auxiliary means is relatively rapid to provide a quick initial response of the control means when the auxiliary means begins its cyclic operation.

Claim 8

A throttle control device for varying the quantity of fuel fed to an engine in a vehicle at each instant in response to variations in the pressure and volume of a hydraulic fluid discharged from a pump means driven by the engine to maintain the engine at speeds approaching idling, including: auxiliary means operable on a cyclic basis and providing a variable load at progressive instants in each cycle to provide the pump means with characteristics of hydraulic flow at the progressive instants in each cycle in accordance with the variable load imposed by the auxiliary means at such instants, throttle means operatively coupled to the engine and variable in position to control the operation of the engine at the idling speeds in accordance with the variations in position, control means operatively coupled to the throttle means to vary the position of the throttle means, the control means having first and second inputs respectively responsive to the cumulative effects of the pressure and volume of the flow of hydraulic fluid from the pump means to the auxiliary means to vary the position of the throttle means in a direction for increasing the speed of the engine in accordance with increases in the pressure and volume of such hydraulic flow; means operatively coupled to the control means for biasing the control means against variations in the position of the throttle means by the pressure and volume of the flow of hydraulic fluid, means operatively coupled to the first input of the control means for introducing fluid to the control means from the pump in accordance with the pressure of such fluid, and means operatively coupled to the second input of the control means for introducing fluid to the control means from the pump in accordance with the volume of flow of such fluid.

Claim 9

A throttle control device for varying the quantity of fuel fed to an engine in a vehicle at each instant in response to variations in the pressure and volume of a hydraulic fluid discharged from a pump means driven by the engine to maintain the engine at speeds approaching idling, including: auxiliary means operable on a cyclic basis and providing a variable load at progressive instants in each cycle to provide the pump means with characteristics of hydraulic flow at the progressive instants in each cycle in accordance with the variable load imposed by the auxiliary means at such instants, throttle means operatively coupled to the engine and variable in position to control the operation of the engine at the idling speeds in accordance with the variations in position, control means operatively coupled to the throttle means to vary the position of the throttle means, the control means having first and second inputs respectively responsive to the cumulative effects of the pressure and volume of the flow of hydraulic fluid from the pump means to the auxiliary means to vary the position of the throttle means in a direction for increasing the speed of the engine in accordance with increases in the pressure and volume of such hydraulic flow; means operatively coupled to the control means for biasing the control means against variations in the position of the throttle means by the pressure and volume of the flow of hydraulic fluid, means operatively coupled to the first input of the control means for introducing fluid to the control means from the pump in accordance with the pressure of such fluid, and means operatively coupled to the second input of the control means for introducing fluid to the control means from the pump in accordance with the volume of flow of such fluid.

Claim 10

A throttle control device as set forth in claim 6, wherein, the control means include a piston movable in a direction for increasing the speed of the engine in accordance with the characteristics of the fluid respectively introduced to the first and second inputs of the control means to represent increases in the pressure and the volume of the fluid flowing from the pump means to the auxiliary means and wherein the throttle means is responsive to the movements of the piston to control the operation of the engine at the idling speeds.

Claim 11

A throttle control device for varying the quantity of fuel fed to an engine in vehicle at each instant in response to variations in the pressure and volume of a hydraulic fluid discharged from a pump means driven by the engine to maintain the engine at speeds approaching idling, including: auxiliary means operable on cyclic basis and providing a variable load at progressive instants in each cycle to provide the pump means with characteristics of hydraulic flow at the progressive instants in each cycle in accordance with the variable load imposed by the auxiliary means at such instants, throttle means operatively coupled to the engine and variable in position to control the operation of the engine at the idling speeds in accordance with the variations in position, control means operatively coupled to the throttle means to vary the position of the throttle means, the control means having first and second inputs respectively responsive to the pressure and volume of the flow of hydraulic fluid from the pump means to the auxiliary means to vary the position of the throttle means in accordance with the pressure and volume of such hydraulic flow; means operatively coupled to the first input of the control means for introducing fluid to the control means from the pump in accordance with the pressure of such fluid, means operatively coupled to the second input of the control means for introducing fluid to the control means from the pump in accordance with the volume of flow of such fluid, the control means including a piston movable in accordance with the characteristics of the fluid respectively introduced to the first and second inputs of the control means to represent the pressure and the volume of the fluid flowing from the pump means to the auxiliary means and the throttle means being responsive to the movements of the piston to control the operation of the engine at the idling speeds, and means included in the control means to provide a lag in the movement of the piston after the introduction of the fluid from the pump means to the auxiliary means.

Claim 12

A throttle control device for varying the quantity of fuel fed to an engine in vehicle at each instant in response to variations in the pressure and volume of a hydraulic fluid discharged from a pump means driven by the engine to maintain the engine at speeds approaching idling, including: auxiliary means operable on cyclic basis and providing a variable load at progressive instants in each cycle to provide the pump means with characteristics of hydraulic flow at the progressive instants in each cycle in accordance with the variable load imposed by the auxiliary means at such instants, throttle means operatively coupled to the engine and variable in position to control the operation of the engine at the idling speeds in accordance with the variations in position, control means operatively coupled to the throttle means to vary the position of the throttle means, the control means having first and second inputs respectively responsive to the pressure and volume of the flow of hydraulic fluid from the pump means to the auxiliary means to vary the position of the throttle means in accordance with the pressure and volume of such hydraulic flow; means operatively coupled to the first input of the control means for introducing fluid to the control means from the pump in accordance with the pressure of such fluid, means operatively coupled to the second input of the control means for introducing fluid to the control means from the pump in accordance with the volume of flow of such fluid, the control means including a piston movable in accordance with the characteristics of the fluid respectively introduced to the first and second inputs of the control means to represent the pressure and the volume of the fluid flowing from the pump means to the auxiliary means and the throttle means being responsive to the movements of the piston to control the operation of the engine at the idling speeds, and means included in the control means to provide a lag in the movement of the piston after the introduction of the fluid from the pump means to the auxiliary means.

Claim 13

A throttle control device for varying the quantity of fuel fed to an engine in a vehicle at each instant in response to variations in the pressure and volume of a hydraulic fluid discharged from a pump means driven by the engine to maintain the engine at speeds approaching idling, including: auxiliary means operable on a cyclic basis and providing a variable load at progressive instants in each cycle to provide the pump means with characteristics of hydraulic flow at the progressive instants in each cycle in accordance with the variable load imposed by the auxiliary means at such instants, throttle means operatively coupled to the engine and variable in position to control the operation of the engine at the idling speeds in accordance with the variations in position, control means operatively coupled to the throttle means to vary the position of the throttle means, the control means having first and second Inputs respectively responsive to the pressure and volume of the flow of hydraulic fluid from the pump means to the auxiliary means to vary the position of the throttle means in accordance with the pressure and volume of such hydraulic flow; means operatively coupled to the first input of the control means for introducing fluid to the control means from the pump in accordance with the pressure of such fluid, means operatively coupled to the second input of the control means for introducing fluid to the control means from the pump in accordance with the volume of flow of such fluid, the control means including a piston movable in accordance with the characteristics of the fluid respectively introduced to the first and second inputs of the control means to represent the pressure and the volume of the fluid flowing from the pump means to the auxiliary means and the throttle means being responsive to the movements of the piston to control the operation of the engine at the idling speeds, and the lagging means including a spring biasing the piston against movement in a direction responsive to the pressure and volume of the fluid flowing from the pump means to the auxiliary means.

Claim 14

A throttle control device for varying the quantity of fuel fed to an engine in a vehicle at each instant in response to variations in the pressure and volume of a hydraulic fluid discharged from a pump means driven by the engine to maintain the engine at speeds approaching idling, including: auxiliary means operable on a cyclic basis and providing a variable load at progressive instants in each cycle to provide the pump means with characteristics of hydraulic flow at the progressive instants in each cycle in accordance with the variable load imposed by the auxiliary means at such instants, throttle means operatively coupled to the engine and variable in position to control the operation of the engine at the idling speeds in accordance with the variations in position, control means operatively coupled to the throttle means to vary the position of the throttle means, the control means having first and second Inputs respectively responsive to the pressure and volume of the flow of hydraulic fluid from the pump means to the auxiliary means to vary the position of the throttle means in accordance with the pressure and volume of such hydraulic flow; means operatively coupled to the first input of the control means for introducing fluid to the control means from the pump in accordance with the pressure of such fluid, means operatively coupled to the second input of the control means for introducing fluid to the control means from the pump in accordance with the volume of flow of such fluid, the control means including a piston movable in accordance with the characteristics of the fluid respectively introduced to the first and second inputs of the control means to represent the pressure and the volume of the fluid flowing from the pump means to the auxiliary means and the throttle means being responsive to the movements of the piston to control the operation of the engine at the idling speeds, and the lagging means including a spring biasing the piston against movement in a direction responsive to the pressure and volume of the fluid flowing from the pump means to the auxiliary means.

Claim 15

A throttle control device for varying the quantity of fuel fed to an engine in a vehicle at each instant in response to variations in the pressure and volume of a hydraulic fluid discharged from a pump means driven by the engine to maintain the engine at speeds approaching idling, including: auxiliary means operable on a cyclic basis and providing a variable load at progressive instants in each cycle to provide the pump means with characteristics of hydraulic flow at the progressive instants in each cycle in accordance with the variable load imposed by the auxiliary means at such instants, throttle means operatively coupled to the engine and variable in position to control the operation of the engine at the idling speeds in accordance with the variations in position, control means operatively coupled to the throttle means to vary the position of the throttle means, the control means having first and second inputs respectively responsive to the pressure and volume of the flow of hydraulic fluid from the pump means to the auxiliary means to vary the position of the throttle means in accordance with the pressure and volume of such hydraulic flow; means operatively coupled to the first input of the control means for introducing fluid to the control means from the pump in accordance with the pressure of such fluid, means operatively coupled to the second input of the control means for introducing fluid to the control means from the pump in accordance with the volume of flow of such fluid, and the pump means including at least a pair of pumps and at least a particular one of the pump means being constructed to provide fluid for operating the auxiliary means only at particular times in each cycle in accordance with the load imposed by the auxiliary means and the means coupled to the second input of the control means providing for the introducton of fluid to such second unit when the particular one of the pump means provides fluid to such second input.

Claim 16

A throttle control device for varying the quantity of fuel fed to an engine in a vehicle at each instant in response to variations in the pressure and volume of a hydraulic fluid discharged from a pump means driven by the engine to maintain the engine at speeds approaching idling, including: auxiliary means operable on a cyclic basis and providing a variable load at progressive instants in each cycle to provide the pump means with characteristics of hydraulic flow at the progressive instants in each cycle in accordance with the variable load imposed by the auxiliary means at such instants, throttle means operatively coupled to the engine and variable in position to control the operation of the engine at the idling speeds in accordance with the variations in position, control means operatively coupled to the throttle means to vary the position of the throttle means, the control means having first and second inputs respectively responsive to the pressure and volume of the flow of hydraulic fluid from the pump means to the auxiliary means to vary the position of the throttle means in accordance with the pressure and volume of such hydraulic flow; means operatively coupled to the first input of the control means for introducing fluid to the control means from the pump in accordance with the pressure of such fluid, means operatively coupled to the second input of the control means for introducing fluid to the control means from the pump in accordance with the volume of flow of such fluid, and the pump means including at least a pair of pumps and at least a particular one of the pump means being constructed to provide fluid for operating the auxiliary means only at particular times in each cycle in accordance with the load imposed by the auxiliary means and the means coupled to the second input of the control means providing for the introducton of fluid to such second unit when the particular one of the pump means provides fluid to such second input.

Claim 17

A throttle control device for varying the quantity of fuel fed to an engine in a vehicle at each instant in response to variations in the pressure and volume of a hydraulic fluid discharged from a pump means driven by the engine to maintain the engine at speeds approaching idling, comprising: auxiliary means for providing a cyclic operation distinct from the movement of the vehicle where the auxiliary means imposes variable magnitudes of load at different times in each cycle, the auxiliary means being opratively coupled to the pump means to provide for the discharge of the hydraulic fluid from the pump means at each instant in accordance with the magnitude of the variable load from the auxiliary means at that instant; first receiving means for receiving at each instant characteristics pRoportional to the volume of hydraulic fluid discharged by the pump means to the auxiliary means at that instant; second receiving means for receiving at each instant characteristics proportional to the pressure of hydraulic fluid discharged by the pump means to the auxiliary means at that instant; control means actuatable by the first and second receiving means at each instant in accordance with the pressure and the volume of the hydraulic fluid respectively introduced to the first and second receiving means to transmit movement to the engine throttle in a direction to maintain the engine at a speed approaching idling with the degree of movement being dependent on both the pressure and volume of fluid discharged by the pump, whereby the torque output of the engine is varied at the engine speeds approaching idling in response to the load requirements imposed upon the pump by the auxiliary means, a movable piston having first and second differential pressure receiveing areas, with the first one of said areas being constructed to receive a pressure dependent upon the output pressure of the hydraulic fluid discharged by the pump means to the auxiliary means and the second one of said areas being constructed to receive a pressure porportional to the volume of the hydraulic fluid discharged by the pump means to the auxiliary means, said piston being operably connected to the control means to transmit movement to the control means in accordance with the volume and pressure of the hydraulic fluid discharged by the pump means to the auxiliary means, and the pump means including at least a pair of pumps and at least a particular one of the pump means being constructed to provide fluid for operating the auxiliary means only at particular times in each cycle in accordance with the load imposed by the auxiliary means and the first receiving means receiving characteristics proportional to the volume of hydraulic fluid discharged by the pump means when the particular one of the pump means provides fluid for operating the auxiliary means.

Claim 18

A throttle control device for varying the quantity of fuel fed to an engine in a vehicle at each instant in response to variations in the pressure and volume of a hydraulic fluid discharged from a pump means driven by the engine to maintain the engine at speeds approaching idling, comprising: auxiliary means for providing a cyclic operation distinct from the movement of the vehicle where the auxiliary means imposes variable magnitudes of load at different times in each cycle, the auxiliary means being opratively coupled to the pump means to provide for the discharge of the hydraulic fluid from the pump means at each instant in accordance with the magnitude of the variable load from the auxiliary means at that instant; first receiving means for receiving at each instant characteristics pRoportional to the volume of hydraulic fluid discharged by the pump means to the auxiliary means at that instant; second receiving means for receiving at each instant characteristics proportional to the pressure of hydraulic fluid discharged by the pump means to the auxiliary means at that instant; control means actuatable by the first and second receiving means at each instant in accordance with the pressure and the volume of the hydraulic fluid respectively introduced to the first and second receiving means to transmit movement to the engine throttle in a direction to maintain the engine at a speed approaching idling with the degree of movement being dependent on both the pressure and volume of fluid discharged by the pump, whereby the torque output of the engine is varied at the engine speeds approaching idling in response to the load requirements imposed upon the pump by the auxiliary means, a movable piston having first and second differential pressure receiveing areas, with the first one of said areas being constructed to receive a pressure dependent upon the output pressure of the hydraulic fluid discharged by the pump means to the auxiliary means and the second one of said areas being constructed to receive a pressure porportional to the volume of the hydraulic fluid discharged by the pump means to the auxiliary means, said piston being operably connected to the control means to transmit movement to the control means in accordance with the volume and pressure of the hydraulic fluid discharged by the pump means to the auxiliary means, and the pump means including at least a pair of pumps and at least a particular one of the pump means being constructed to provide fluid for operating the auxiliary means only at particular times in each cycle in accordance with the load imposed by the auxiliary means and the first receiving means receiving characteristics proportional to the volume of hydraulic fluid discharged by the pump means when the particular one of the pump means provides fluid for operating the auxiliary means.