Active vibration damping support device

A solenoid driving device with excellent electric power efficiency which drives and controls an actuator including a solenoid and an active vibration damping support device with excellent electric power efficiency which includes the solenoid driving device are disclosed. The solenoid driving device includes a booster circuit 120 which boosts a battery voltage, and driving circuits 121A, 121B which an actuator with the electric power supplied and boosted by the booster circuit 120. ACM_ECU200A including a micro computer 200b calculates the magnitude of the vibration of the engine, an engine vibration cycle and a phase lag to obtain the drive frequency fDV of the actuator in the vibration state estimating unit 234 and the phase detecting unit 235. A booster circuit controlling unit 237 of the micro computer 200b determines the target voltage V based on the drive frequency fDV. The target voltage V is input to the booster circuit 120, and the booster circuit 120 supplies the required electric power to the driving circuits 121A, 121B at the target voltage V*.

FIELD OF THE INVENTION

The present invention relates to an active vibration damping support device which supports an engine of a vehicle and more particularly relates to an active vibration damping support device provided in a hybrid vehicle.

DESCRIPTION OF THE RELATED ARTS

A vehicle has been known which is provided with an active vibration damping support device that absorbs the vibration of an engine equipped in a vehicle to suppress the transmission of the vibration to a vehicle body. For example, a patent document 1 discloses a technique in which an active vibration damping support device is provided in a hybrid vehicle including an electric motor that is an auxiliary driving source of the output of an engine to absorb the vibration generated in the engine.Patent Document 1: Unexamined Japanese Patent Application Publication No. 2007-269049

SUMMARY OF THE INVENTION

Problem to be Solved by the Invention

However, when the rotation speed of the engine is varied irregularly, such as when the engine is started, it is difficult to predict the status of the vibration of the engine which includes roll vibration, especially, roll proper vibration. Thus, there has been a problem that the engine vibration including roll proper vibration can not be preferably absorbed by the active vibration damping support device and the engine vibration is transmitted to the vehicle body.

When the engine vibration is transmitted to the vehicle body, a driver feels uncomfortable.

An object of the present invention is to provide an active vibration damping support device that predicts the vibration status of roll vibration when the engine is started so as to preferably absorb the roll vibration.

Means to Solve the Problem

In order to solve the problem, the present invention provides an active vibration damping support device which supports an engine started to be driven by an electric motor and absorbs vibration generated in the engine by expansion and contraction of an actuator. The active vibration damping support device is characterized in that when the engine is started, the expansion and contraction of the actuator is started after a predetermined time set in advance has passed since a time when the electric motor is started to be driven.

In accordance with the present invention, the expansion and contraction (control) of the actuator provided in the active vibration damping support device can be started when the predetermined time has passed since the engine was started.

By setting the predetermined time in advance, it is possible to start the control of the actuator of the active vibration damping support device after the set time has been passed since the electric motor was started to be driven to start the engine.

Further, in the active vibration damping support device of the present invention, the active vibration damping support device is provided in a vehicle in which the electric motor can be driven at a predetermined rotation speed set in advance to start the engine.

In accordance with the present invention, the active vibration damping support device can be provided in the vehicle in which the electric motor can be driven at the predetermined rotation speed set in advance to start the engine.

By setting the rotation speed of the electric motor in advance, it is possible to control the rotation speed of the engine when starting the engine.

In the present invention, the predetermined time is a time taken for the rotation speed of the engine driven and rotated by the electric motor to reach a predetermined rotation speed from a stop state.

In accordance with the present invention, it is possible to start the control of the actuator provided in the active vibration damping support device when the rotation speed of the engine reaches the predetermined rotation speed at the start time of the engine.

Further, in the present invention, the predetermined rotation speed is a rotation speed at which roll vibration is generated in the engine.

In accordance with the present invention, it is possible to start the control of the actuator provided in the active vibration damping support device when the roll vibration is generated in the engine at the start time of the engine.

The amplitude and continuation time period of the roll vibration generated when the engine is started have been known to be determined by a time taken for the roll vibration to be generated since the engine was started.

Therefore, by setting the time taken for the roll vibration to be generated since the engine was started, the active vibration damping support device is configured to be capable of accurately predicting the amplitude and the continuation time period of the roll vibration.

If the amplitude and the continuation time period of the roll vibration can be accurately predicted, the active vibration damping support device can be configured to preferably absorb the roll vibration by controlling the operation of the actuator based on the prediction.

Effect of the Invention

In accordance with the present invention, an active vibration damping support device can be provided which accurately predicts the vibration status of the roll vibration when the engine is started so that the roll vibration can be preferably absorbed.

EMBODIMENTS FOR CARRYING OUT THE INVENTION

An embodiment of the present invention is described in detail below with reference to the accompanying drawings.

An active vibration damping support device1according to the embodiment can be driven to expand and contract in a vertical direction, and includes active control mounts (hereinafter, referred to as ACMs)10which are used to elastically support an engine2of a hybrid-vehicle (vehicle) V in a vehicle body frame and are disposed ahead of and behind the engine2, respectively, as shown inFIGS. 1A and 1B.

Here, the engine2is a so-called side-ways mounted transversal V engine with six-cylinders in which one end of a crankshaft (not shown) is connected to a transmission3, and the crankshaft is disposed in a direction transverse to a body of the hybrid vehicle V. Therefore, the engine2is disposed such that the direction of the crankshaft is in a direction transverse to the body of the hybrid vehicle V, and the ACMs10are disposed ahead of and behind the engine2as a pair to absorb vibration generated at the engine2in a roll direction (a roll vibration). Hereinafter, the ACM10which is disposed ahead of the engine2of the hybrid vehicle V is referred to as a front ACM10aand the ACM10which is disposed behind the engine2is referred to as a rear ACM10bas appropriate.

The roll vibration is vibration generated in the rotation direction of the crank shaft. If the engine2is mounted transversely, the roll vibration is generated in the front-rear direction of the hybrid vehicle V.

The roll vibration is generated when the rotation speed reaches a predetermined rotation speed at the time when the engine2is started, for example. Hereinafter, the rotation speed at which the roll vibration is generated in the engine2is referred to as a roll vibration rotation speed. The roll vibration rotation speed of the rotation speed of the engine2corresponds to a predetermined rotation speed recited in Claims.

The roll vibration rotation speed is a value determined by the characteristic of the engine2, such as its weight or character frequency and can be determined in advance by an experiment or the like.

The hybrid vehicle V also includes an electric motor4which is an auxiliary driving force of the engine2.

For example, the electric motor4used in a hybrid system “IMA (Integrated motor assist) system” the applicant has invented is a thin DC brushless motor which is sandwiched between the engine2and the transmission3and is directly connected to the engine2. The electric motor4generates a large output torque to assist the engine2when the load of the engine2is large, such as when the vehicle is accelerated.

The rotation speed of the electric motor4when the hybrid vehicle V is running is set by the engine ECU61which is described later (seeFIG. 2) based on the rotation speed of the engine2by using an algorithm set in advance.

Further, the engine ECU61controls the electric motor4to drive the electric motor4at the set rotation speed.

The electric motor4which is provided in the hybrid vehicle V (seeFIG. 1A) and is an auxiliary driving source of the output of the engine2is configured such that the electric motor4can be driven at the rotation speed set in advance.

With this configuration, the electric motor4can preferably assist the engine2.

Further, when the engine2is started, the electric motor4can rotate and crank the crank shaft (not shown) to start the engine2as a cell motor.

When starting the engine2, it is preferable that the rotation speed of the electric motor4is controlled by the engine ECU61(seeFIG. 2) so that the electric motor4is driven at the rotation speed set in advance to start the engine2.

The front ACM10aand the rear ACM10bthat constitute the active vibration damping support device1are mounted on a position lower than the height of the gravity center of the engine2. The front ACM10aand the rear ACM10bhave functions of absorbing the roll vibration generated in the front-rear direction in the engine2and elastically supporting the engine2in the vehicle body of the hybrid vehicle V.

As shown inFIG. 1B, the active vibration damping support device1has functions of elastically supporting the engine2in the hybrid vehicle V and moving the front part or the rear part of the engine2in an up-down direction. Thus, the active vibration damping support device1has a structure shown inFIGS. 2 and 3.

As shown inFIG. 2, the active vibration damping support device1(seeFIG. 1A) includes an active control mount ECU (Electronic Control Unit, hereinafter referred to as an ACMECU)62which controls the ACMs10. The ACMECU62is connected with a communication line to the engine ECU61that controls the engine rotation speed and the output torque of the engine2(seeFIG. 1B).

Input to the ACMECU62from the engine ECU61are an NE signal indicating the engine rotation speed, a CP signal indicating a crank pulse detected by the crank pulse sensor60, a TDC (Top Dead Center) pulse signal indicating the top dead center of each cylinder, a SO (cylinder off) signal indicating whether the V-six engine2is in an all-cylinder operation state or a selective cylinder operation state, an IF-SW signal indicating the operation state (the turning ON of the ignition switch) of the ignition switch (not shown), and an accelerator position sensor signal indicating the opening degree of an accelerator.

In a case of the V-six engine, the crank pulse is output 24 times per one rotation of the crank shaft (i.e. one time every 15 degrees of the crank angle).

As shown inFIG. 2, the ACM10has a structure that is substantially symmetrical with respect to an axis LA, and includes a substantially cylindrical upper housing11, a substantially cylindrical lower housing12disposed below the housing11, an upwardly opening substantially cup-shaped actuator case13housed in the lower housing12, a diaphragm22connected on the upper housing11, an annular first elastic body support ring14housed in the upper housing11, a first elastic body19connected on the first elastic body support ring14, an annular second elastic body support ring15housed in the actuator case13, a second elastic body27connected to an inner peripheral side of the second elastic body support ring15, and a driving unit (actuator)41housed in the actuator case13and disposed below the second elastic body support ring15and the second elastic body27.

Between a flange unit11aat the lower end of the upper housing11and a flange unit12aat the upper end of the lower housing12, a flange unit13aon the outer periphery of the actuator case13, an outer peripheral unit14aof the first elastic body support ring14, and an upper and outer peripheral unit15aof a second elastic body support ring15which is disposed in an upper part of the actuator case13and has a substantially transverse U shape in an annular cross-section with upper and lower outer peripheral portions are superimposed and joined by crimping. In this process, an annular first floating rubber16is disposed between the flange unit12aand the flange unit13a, and an annular second floating rubber17is disposed between an upper side of the flange unit13aand lower side of the upper and outer peripheral unit15a, so that the actuator case13is floatingly supported such that it can move up and down relative to the upper housing11and the lower housing12.

The first elastic body support ring14, and a first elastic body support boss18disposed in a concave unit provided on the upper side of a first elastic body19are joined by vulcanization bonding at the lower and upper ends of the first elastic body19made of a thick rubber. Further, a diaphragm support boss20is fixed to an upper face of the first elastic body support boss18by a bolt21. An outer peripheral unit of a diaphragm22whose inner peripheral unit is joined by vulcanization bonding to the diaphragm support boss20, is joined by vulcanization bonding to the upper housing11.

An engine mounting unit20aintegrally formed with an upper face of the diaphragm support boss20is fixed to the engine2(seeFIG. 1A). (Detailed method for fixing is not shown). Also, a vehicle body mounting unit12bat the lower end of the lower housing12is fixed to the vehicle body frame F (not shown).

A flange unit23aat the lower end of a stopper member23is joined to a flange unit11bby bolts24and nuts25at the upper end of the upper housing11. The engine mounting unit20aprovided on the diaphragm support boss20faces a stopper rubber26attached to an upper inner face of the stopper member23so that the engine mounting unit20acan touch the stopper rubber26.

By such a structure, when a large load is input from the engine2(seeFIG. 1A) to the ACM10, the engine mounting unit20atouches the stopper rubber26, thereby reducing excessive displacement of the engine2.

An outer peripheral unit of a second elastic body27made of a membranous rubber is joined to the inner peripheral face of the second elastic body support ring15by vulcanization bonding. At a center portion of the second elastic body27, a movable member28is joined by vulcanization bonding so that the upper unit thereof is embedded in.

A disc-shaped partition member29is fixed between an upper face of the second elastic body support ring15and the lower unit of the first elastic body support ring14. A first liquid chamber30defined by the first elastic body support ring14, the first elastic body19and the partition member29, and a second liquid chamber31defined by the partition member29and the second elastic body27, communicate with each other via a through hole29aformed in the center of the partition member29.

The outer peripheral unit27aof the second elastic body27is held between a lower and outer peripheral unit15bof the second elastic body support ring15(seeFIG. 3) and a yoke44described below to function as a seal.

Also, an annular through passage32is formed between the first elastic body support ring14and the upper housing11. The through passage32communicates with the first liquid chamber30via a through hole33, and communicates via a through gap34with a third liquid chamber35defined by the first elastic body19and the diaphragm22.

Next, a detailed structure of the driving unit41stored in the actuator case13and shown inside of the broken line is described with reference toFIG. 3.

As shown inFIG. 3, the driving unit41is comprised of a stationary core42made of metal or alloy which has high magnetic permeability, a coil assembly43, a yoke44, and a movable core54, etc.

The stationary core42is a substantially cylindrical shape including, at a lower end thereof, a flange part which is a seating face. The outer periphery of a cylindrical part is the peripheral shape of a circular cone. The movable core54has a substantially cylindrical shape, and the movable core54protrudes in the inner circumferential direction so as to form a spring seat54a. The inner circumference of a cylindrical part which is lower than the spring seat54ahas the peripheral shape of a circular cone.

The coil assembly43includes a cylindrical coil46disposed between the stationary core42and the yoke44, and a coil cover47covering the outer periphery of the coil46. The coil cover47is integrally formed with a connector48running through openings13band12cformed in the actuator case13and the lower housing12and extending outward, and an electric supply line is connected to the connector48to supply electric power to the coil46.

The yoke44has an annular flange on the upper side of the coil cover47, and has a cylindrical unit44aextending downward from the inner peripheral unit of the flange. The yoke44has, as it were, a configuration of cylinder having flange. A seal49is disposed between an upper face of the coil cover47and a lower face of the annular flange of the yoke44. A seal50is disposed between a lower face of the coil cover47and an upper face of the stationary core42. These seals49and50can prevent water or dust from entering an internal space of the driving unit41via the openings13band12cformed in the actuator case13and the lower housing12.

A thin cylindrical bearing member51is fitted, in a vertically slidable manner, into an inner peripheral face of a cylindrical unit44aof the yoke44. An upper flange51aand a lower flange51bare formed at the upper end and the lower end respectively of the bearing member51, the upper flange51abeing bent radially inward, the lower flange51bbeing bent radially outward.

A set spring52is disposed in a compressed state between the lower flange51band the lower end of the cylindrical unit44aof the yoke44. The bearing member51is supported by the yoke44by the lower flange51bbeing pressed against the upper face of the stationary core42via an elastic body53disposed between the lower face of the lower flange51band the stationary core42by means of an elastic force of the set spring52.

A substantially cylindrical movable core54is fitted, in a vertically slidable manner, into an inner peripheral face of the bearing member51. Further, the stationary core42and the movable core54have hollow center portions on the axis L respectively, and a substantially cylindrical rod55, which connects to the center of the movable member28(on the axis L) and extends downwardly, is inserted there. A nut56is tightened around the lower end of the rod55. The nut56has a hollow part at its center, the upper end of the hollow part opens upward, and receives the lower end of the rod55in the hollow part. An upper end56aof the nut56has a slightly larger outer diameter than that of its lower portion. An upper face of the upper end56atouches the lower face of the spring washer54a.

Also, a set spring58is disposed in a compressed state between the spring washer54aof the movable core54and a lower face of the movable member28. The lower face of the spring washer54aof the movable core54is fixed by being pressed against the upper end56aof the nut56by means of an elastic force of the set spring58. In this state, the conical inner peripheral unit of the cylindrical unit of the movable core54and the conical outer peripheral unit of the stationary core42face each other across a conical air gap g.

Relative to the rod55, the nut56is tightened in an opening42aformed in the center of the stationary core42with position adjustment in vertical direction. This opening42ais blocked by a rubber cup60.

The operation of the ACM10which is configured as described above is explained below (seeFIGS. 1 to 3as appropriate).

As shown inFIG. 2, a crank pulse sensor60and a cam angle sensor63are connected to the engine ECU61. The crank pulse sensor60outputs a CP signal indicating a crank pulse which is output 24 times per one rotation of the crank shaft (not shown) of the engine2(seeFIG. 1A) (i.e. once every 15 degrees of the crank angle).

The cam angle sensor63outputs a TDC pulse signal indicating the timing of the top dead center three times per one rotation of the crank shaft (i.e. once every time the top dead center is reached in each cylinder).

Further, the ACM ECU62is connected to the engine ECU61, and the CP signal and the TDC pulse signal are input to the ACM ECU62from the engine ECU61.

The ACM ECU62estimates the vibration status of the engine2based on the CP signal and the TDC pulse signal which are input to the ACM ECU62from the engine ECU61and controls the electricity to be supplied to the driving unit41of the two ACMs10(the front ACM10aand the rear ACM10b) that comprises the active vibration damping support device1

A coil46of the driving unit41shown inFIG. 3is excited by electric power (excitation current) supplied from the ACM_ECU62so as to move a movable core54by sucking force to move a movable member28downward. Associated with movement of this movable member28, a second elastic body27which defines a second liquid chamber31is downwardly deformed so as to increase the capacity of the second liquid chamber31. Conversely, when the coil46is demagnetized, the movable member28and the movable core54move upward by the elasticity of the second elastic body27, and the capacity of the second liquid chamber31decreases.

A low frequency engine shake vibration (e.g., 7-20 Hz) is caused by a resonance between the vehicle body and the engine system in a coupled system including the engine2, the vehicle body, and a suspension. When the low frequency engine shake vibration occurs while the hybrid vehicle V is traveling, the first elastic body19is deformed by a load input from the engine via the diaphragm support boss20and the first elastic body support boss18, thus changing the capacity of the first liquid chamber30, so that a liquid moves to and fro between the first liquid chamber30and the third liquid chamber35via the through passage32. In this state, when the capacity of the first liquid chamber30increases/decreases, the capacity of the third liquid chamber35decreases/increases correspondingly, and this change in the capacity of the third liquid chamber35is absorbed by elastic deformation of the diaphragm22. The shape and the dimensions of the through passage32and the spring constant of the first elastic body19are set such that a low spring constant and high attenuation force are exhibited in the frequency region of the engine shake vibration. Therefore, it is possible to effectively reduce the vibration transmitted from the engine2to the vehicle body frame F.

Further, in the frequency region of the engine shake vibration, when the engine2is in a steady rotating state, the driving unit41is maintained in a non-operating state.

When vibration occurs which has a higher frequency than that of the above-mentioned engine shake vibration, that is, vibration during idling or vibration during selective-cylinder operation due to the rotation of the crankshaft (not shown) of the engine2, the liquid within the through passage32providing communication between the first liquid chamber30and the third liquid chamber35becomes stationary and a vibration isolating function cannot be exhibited. Therefore, the ACM ECU62performs a vibration isolating function by driving the driving units41,41of the front ACM10aand the rear ACM10bto absorb the vibration.

Thus, the ACM ECU62which controls the active vibration damping support device1including the front ACM10aand the rear ACM10bdrives the driving unit41by controlling excitation current to be supplied to the coil46on the basis of signals input from the crank pulse sensor60, the cam angle sensor63, and the engine ECU61.

For reference's sake, the idle vibration is caused by low-frequency vibrations of a floor, seats, and a steering wheel during idling. For example, BURUBURU vibration is caused in a four-cylinder engine in a range of 20-35 Hz, and in a six-cylinder engine in a range of 30-50 Hz, and YUSAYUSA vibration is caused in a range of 5-10 Hz by uneven combustion, and the main factor of the YUSAYUSA vibration is roll vibration in the engine.

As shown inFIG. 4, the engine ECU61is comprised of a micro computer including a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory) and a peripheral circuit or the like and performs functions of controlling the rotation speed of the engine2or detecting the rotation speed of the engine2via the rotation speed sensor (not shown) provided to the engine2. Then the engine ECU61inputs the detected rotation speed to the ACM ECU62as an NE signal. Further, the engine ECU61inputs the CP signal input from the crank pulse sensor60and the TDC pulse signal input from the cam angle sensor63to the ACM ECU62.

The ACM ECU62is comprised of a micro computer including a CPU62b, a ROM62c, a RAM62d, etc. and a peripheral circuit. The ACM ECU62also includes a signal input unit62ato which the NE signal, the CP signal and the TDC pulse signal are input from the engine ECU61.

Further, the ACM ECU62includes a power feeding circuit62fwhich has a switching circuit (not shown) and supplies excitation current to the coils46(seeFIG. 3) in the front ACM10aand the rear ACM10b, respectively. The switching circuit of the power feeding circuit62fis controlled by the CPU62bsuch that the power feeding circuit62fcan supply a direct current power source provided from a battery (not shown) to the coils46through a connector48(seeFIG. 3). By making the CPU62bexecute a program stored, for example, in the ROM62c, the ACM ECU62controls the two ACMs10.

In the driving unit41of the ACM10configured as shown inFIG. 3, when an excitation current is not supplied to the coil46, a movable member28is upwardly moved by elastic restorative force of a second elastic body27. Also, a nut member56pushes a movable core54up to form an air gap g between the movable core54and the stationary core42.

On the other hand, when an excitation current is supplied from the power feeding unit62fof the ACM ECU62to the coil46, the movable core54is attracted and moved downward by magnetic flux passing through the air gap g in the up-down direction. At this time, the movable core54moves the movable member28downward via the nut member56fixed to the movable member28so as to deform the second elastic body27downward. As a result, since the capacity of the second liquid chamber31(seeFIG. 1) increases, a liquid in the first liquid chamber30compressed by load from the engine2(seeFIG. 1A) flows into the second liquid chamber31through the through hole29aof the partition member29to reduce load transmitted from the engine2to the hybrid vehicle V (SeeFIG. 1A).

As described above, the ACM ECU62can control the vertical motion of the movable member28by controlling ON and OFF of the excitation current supplied to the coil46. This makes it possible for the ACM10to absorb the vibration generated at the engine2.

Next, the operation of ACMECU62will be explained with reference toFIG. 5(also refer toFIGS. 1-4as appropriate).

As shown inFIG. 5, the ACMECU62includes as its functional blocks a crank pulse interval calculation unit621, an engine rotation mode determination unit622, a vibration state estimating unit623, a phase detecting unit624, and an actuator driving control unit625.

These functional blocks are realized when the CPU62bexecutes programs stored, for example, in the ROM62c.

The crank pulse interval calculation unit621calculates an interval of the crank pulse based on an internal clock signal of the CPU62b, a crank pulse signal and a TDC pulse signal input from the engine ECU61.

The crank pulse interval calculated by the crank pulse interval calculation unit621is sent to the engine rotation mode determination unit622and the vibration state estimating unit623.

The NE signal, the CO signal, the IG-SW signal, the accelerator position sensor signal, and the IJ signal are input from the engine ECU61to the engine rotation mode determination unit622. The engine rotation mode determination unit622determines the rotation mode of the engine2based on these signals.

For example, if the engine rotation speed is increased when the IJ signal is not input, the engine rotation mode determination unit622determines that the engine rotation mode is a motoring mode where the engine2is driven by the electrical motor4.

The engine rotation mode determination unit622also includes functions of determining whether the engine102is in an all-cylinder operation state or a selective cylinder operation state based on the SO signal and determining an idling state based on the accelerator position sensor signal.

The vibration state estimating unit623calculates the rotational fluctuation of the crank shaft based on the crank pulse interval calculated by the crank pulse interval calculation unit621when the engine2is driven in any of the following driving modes: the idling mode, the all-cylinder operation state or the selective cylinder operation state. Further, the vibration state estimating unit623calculates the magnitude and the cycle of the engine vibration based on the P-P value (the interval between a peak to the next peak) of the calculated rotational fluctuation of the crank shaft. Provided that the magnitude of the engine vibration and the cycle of the engine vibration are included in and referred to as a vibration state in this specification, the vibration state estimating unit623can be understood as having a function for estimating the vibration state.

The vibration state estimating unit623outputs the estimated vibration state (the magnitude and cycle of the engine vibration) and the peak to peak timing of the rotational fluctuation of the crank shaft, etc. to the phase detecting unit624and the actuator driving control unit625.

The vibration state estimating unit623estimates the vibration state based on the rotational mode of the engine2which is determined by the engine rotation mode determination unit622, and outputs the vibration state.

For example, when the engine2is a V-type six-cylinder engine, the vibration state estimating unit623estimates that the vibration is the third order engine vibration in the case of all-cylinder operation state, and estimates that the vibration is 1.5th order engine vibration in the case of selective cylinder operation state.

Since the method for estimating this vibration state is disclosed in, for example, “111 Development of active engine mount”, JSAE Annual Congress (Autumn), Sep. 18, 2003, detailed description will be omitted.

The vibration state estimating unit623also includes a function of determining that the roll vibration is generated in the engine2when the engine rotation speed calculated based on the NE signal reaches the roll vibration rotation speed.

When the engine2is in the idling state, all-cylinder operation state, or selective cylinder operation state, the phase detector624compares the timing of the peak of the rotation fluctuation of the crankshaft and the timing of TDC based on the peak-to-peak value of the rotation fluctuation of the crankshaft calculated by the vibration state estimating unit623, the CP signal output from the engine ECU73and the TDC pulse signal for each cylinder and detects the phase of the vibration generated in the engine2. The vibration state estimating unit623then outputs the detected phase to the actuator driving control unit625.

The actuator driving control unit625calculates the waveform of the excitation current which can realize a mount operation that absorbs the vibration of the engine2based on the phase detected by the phase detecting unit624and the engine rotation speed. The actuator driving control unit625then supplies the excitation current of the calculated waveform to the driving units41of the front ACM10aand the rear ACM10bto expand or contract (control) the two ACMs10.

The engine ECU61shown inFIG. 4calculates the engine rotation speed and inputs the calculated engine rotation speed to the ACM ECU62as the NE signal based on the CP signal input from the crank pulse sensor60and the TDC pulse signal, etc.

The ACM ECU62which is configured as shown inFIG. 5calculates the magnitude and cycle of the vibration generated in the engine2and the timing of the peaks of the rotation fluctuation of the crankshaft as described above and controls the two ACMs10such that the two ACMs10absorb the vibration of the engine2.

With this configuration, the active vibration damping support device1can absorb the vibration generated in the engine2and suppress the transmission of the vibration to the vehicle body frame F.

Conventionally, in the ACM ECU62shown inFIG. 4the vibration state estimating unit623(seeFIG. 5) predicts that the roll vibration will be generated in the engine2and starts to control the two ACMs10when the engine rotation speed calculated based on the NE signal input from the engine ECU61reaches the roll vibration rotation speed at the start time of the engine2.

For example, when the engine2(seeFIG. 1A) is started, correlations such as the those shown inFIG. 6have been known among a rise time in which the engine rotation speed reaches the roll vibration rotation speed (the rise time of the engine2), the amplitude (magnitude) of the roll vibration and the time period in which the roll vibration continues (a roll vibration period).

Hereinafter, the magnitude and cycle of the roll vibration and the roll vibration period are collectively referred to as the vibration status of the roll vibration.

As shown inFIG. 6, the shorter the time period taken for the engine rotation speed to reach the roll vibration rotation speed is and the more rapid the engine rotation speed is increased, the smaller the magnitude of the roll vibration generated in the engine2(seeFIG. 1A) is and the shorter the roll vibration period is. This means that the shorter the rise time of the engine2is, the smaller the magnitude of the roll vibration of the engine2is and the shorter the roll vibration period is.

Therefore, if the rise time taken for the engine rotation speed to reach the roll vibration rotation speed from 0 is known, the vibration state estimating unit623(seeFIG. 5) in the ACM ECU62can predict the magnitude of the roll vibration generated in the engine2(seeFIG. 1A) and the roll vibration period by referring to the graph shown inFIG. 6. In short, the vibration state estimating unit623has a functions as a prediction unit for predicting the vibration status of the roll vibration.

Therefore, it is preferable to configure that the graph shown inFIG. 6is stored, for example, in the ROM62c(seeFIG. 4) of the ACM ECU62as a map, for example.

The vibration state estimating unit623(seeFIG. 5) of the ACM ECU62can predict the magnitude of the roll vibration generated in the engine2(seeFIG. 1A) and the roll vibration period by referring to the map stored in the ROM62cbased on the rise time of the engine2in which the engine rotation speed reaches the roll vibration rotation speed from 0.

For example, the vibration state estimating unit623(seeFIG. 5) of the ACM ECU62measures the time taken for the engine rotation speed to reach the roll vibration rotation speed since an ignition switch (not shown) is turned ON to calculate the rise time of the engine2. Thus, the vibration state estimating unit623can predict the magnitude of the roll vibration and the roll vibration period with reference to the map stored in the ROM62c(seeFIG. 4) based on the calculated rise time of the engine2.

Then, after the vibration state estimating unit623shown inFIG. 5calculates the cycle of the roll vibration, the vibration state estimating unit623inputs the vibration status of the predicted roll vibration (the magnitude and the cycle of the roll vibration and the roll vibration period) to the actuator driving control unit625and the phase detecting unit624.

The phase detecting unit624shown inFIG. 5compares the timing of the peak of the rotation fluctuation of the crankshaft and the timing of the top dead center of each cylinder to detect the phase of the roll vibration based on the input vibration status of the roll vibration. The detected phase is output to the actuator driving control unit625.

The actuator driving control unit625shown inFIG. 5calculates the waveform of the excitation current which can realize an mount operation that absorbs the vibration of the engine2(seeFIG. 1A) based on the phase detected by the phase detecting unit624and the engine rotation speed. The actuator driving control unit625then supplies the excitation current of the calculated waveform to the respective driving unit41of the front ACM10a(seeFIG. 1A) and the rear ACM10b(seeFIG. 1A) to expand or contract the two ACMs10.

The actuator driving control unit625controls the two ACMs10as described above during the roll vibration period predicted by the vibration state estimating unit623so that the two ACMs10absorb the roll vibration generated at the start time of the engine2.

At the time when the engine2(seeFIG. 1A) is started, however, the engine rotation speed is varied irregularly. Thus, the magnitude of the roll vibration or the roll vibration period predicted by the vibration state estimating unit623(seeFIG. 5) of the ACM ECU62based on the engine rotation speed calculated by the engine ECU61(seeFIG. 4) from the CP signal and the TDC pulse signal may not be accurately same as the vibration status of the roll vibration actually generated in the engine2.

In view of the above problem, the hybrid vehicle V (seeFIG. 1A) according to the embodiment is configured to start the engine2(seeFIG. 1A) by the electrical motor4(seeFIG. 1A) which is an auxiliary driving source of an engine output.

The hybrid vehicle V (seeFIG. 1A) according to the embodiment is characterized in that the rotation speed of the electrical motor4is controlled such that the engine rotation speed reaches the roll vibration rotation speed in a predetermined time period at the start time of the engine2.

Generally, a motor used for a cell motor (not shown) for starting the engine2(seeFIG. 1A) has a small output torque, and thus the motor can not accurately control the rotation speed of the crankshaft (not shown) of the engine2although it can rotate the crankshaft.

Therefore, the engine rotation speed is varied irregularly at the time when the engine2is started.

On the other hand, a motor whose output torque is large is used for the electrical motor4(seeFIG. 1A) of the hybrid vehicle V so that the motor can be an auxiliary driving source of the engine output.

Further, the electrical motor4provided to the hybrid vehicle V can control the rotation speed, as described above. In other words, the rotation speed can be set in advance.

Therefore, the electrical motor4can precisely control the rotation speed of the crankshaft (not shown) of the engine2(seeFIG. 1A) (i.e. engine rotation speed) at the engine start time. For example, the time taken for the engine2to reach a predetermined rotation speed can be set in advance.

With this configuration, the ACM ECU62(seeFIG. 4) can precisely grasp the rise time in which the engine rotation speed reaches the roll vibration rotation speed at the start time of the engine2(seeFIG. 1A) of the hybrid vehicle V.

For example, when an ignition switch (not shown) is turned ON at the time t0, the electrical motor4(seeFIG. 1A) is started to be driven, and the engine rotation speed starts to increase from 0 rpm as shown inFIG. 7.

When the engine rotation speed is increased by driving the electrical motor4and reaches the roll vibration rotation speed Ne1at the time t1, the roll vibration is generated in the engine2(seeFIG. 1A).

If the electrical motor4which is the auxiliary driving source of the output of the engine2(seeFIG. 1A) is used at the start time of the engine2(seeFIG. 1A) of the hybrid vehicle V, a rise time period ΔT1(time t0→t1) in which the engine rotation speed reaches the roll vibration rotation speed Ne1since the electrical motor4is started by turning on the ignition switch is determined by the rotation speed of the electrical motor4.

That is, if the rotation speed of the electrical motor4is set in advance, the rise time period ΔT1in which the engine rotation speed reaches the roll vibration rotation speed Ne1becomes always constant.

In the embodiment, the rise time period ΔT1corresponds to a predetermined time period recited in Claims.

For example, the rise time period ΔT1in which the engine rotation speed reaches the roll vibration rotation speed Ne1since the ignition switch (not shown) is turned on is set in advance and the rotation speed of the electrical motor4(seeFIG. 1A) is set to realize the rise time period ΔT1.

If the rise time period ΔT1is stored, for example, in the ROM62c(seeFIG. 4), the vibration state estimating unit623(seeFIG. 5) of the ACM ECU62can grasp the rise time period ΔT1precisely.

If the rise time period ΔT1in which the engine rotation speed reaches the roll vibration rotation speed Ne1is always constant, the magnitude of the roll vibration and the roll vibration period derived from the graph shown inFIG. 6are always constant.

Since the engine2(seeFIG. 1A) is driven and rotated by the electrical motor4(seeFIG. 1A) whose output torque is large at the start time of the engine2, the rotation fluctuation of the crankshaft (not shown) become always the same every time the engine2is started.

Therefore, it is anticipated that the cycle of the vibration (the cycle Tr of the roll vibration) of the engine2calculated from the rotation fluctuation of the crankshaft will be the same every time the engine2is started.

Specifically, the vibration status of the roll vibration including the magnitude of the roll vibration Xr, the cycle Tr and the roll vibration period ΔT2can be set in advance which correspond to the rise time period ΔT1which is set in advance. The ACM ECU62(seeFIG. 4) can control the two ACMs10(seeFIG. 1A) based on the vibration status of the roll vibration which is set in advance.

In other words, the ACM ECU62can accurately predict the vibration status of the roll vibration generated in the engine2and control the two ACMs10.

For example, the ACM ECU62(seeFIG. 4) does not need to obtain the magnitude of the roll vibration Xr and the roll vibration period ΔT2which correspond to the rise time period ΔT1in which the engine rotation speed reaches the roll vibration rotation speed Ne1with reference toFIG. 6and does not need calculate the cycle Tr of the roll vibration. Therefore, it is possible to improve the calculation speed of the ACM ECU62when the ACM ECU62controls the two ACMs10(seeFIG. 1A) at the start time of the engine2and to start the control of the two ACMs10immediately when the roll vibration is generated in the engine2.

As the ACM ECU62(seeFIG. 4) controls the two ACMs10(seeFIG. 4) based on the vibration status of the roll vibration which has been set in advance, the ACM ECU62just controls the two ACMs10in the same manner every time the engine2(seeFIG. 4) is started.

For example, if the vibration status (the magnitude of the roll vibration Xr, the cycle Tr and the roll vibration period ΔT2) of the roll vibration at the start time of the engine2is determined, the operation of the two ACMs10that can most effectively absorb the roll vibration generated in the engine2can be set by an experiment or the like.

By making the ACM ECU62to control the two ACMs10so as to realize the operation of the two ACMs10set as describe above, the roll vibration generated in the engine2can be preferably absorbed by the two ACMs10, whereby the transmission of the roll vibration to the vehicle body frame F (seeFIG. 2) can be suppressed.

Further, as the roll vibration is generated in the engine2(seeFIG. 4) when the engine rotation speed reaches the roll vibration rotation speed Ne1, the ACM ECU62(seeFIG. 4) can precisely grasp the time taken for the roll vibration to be generated in the engine2since the ignition switch (not shown) is turned on.

The ACM ECU62can start to control the two ACMs10(seeFIG. 4) at the time t1when the engine rotation speed reaches the roll vibration rotation speed Ne1. In short, the ACM ECU62can start to control the two ACMs10at the timing in which the roll vibration is generated in the engine2. Therefore, the roll vibration generated in the engine2can be preferably absorbed, and thus the transmission of the roll vibration to the vehicle body frame F (seeFIG. 2) can be suppressed.

For example, a series of the operation of the two ACMs10(seeFIG. 1A) from the time t0when the ignition switch (not shown) is turned on to the time t2when the roll vibration period ΔT2is finished via the time t1when the engine rotation speed reaches the roll vibration rotation speed Ne1can be set in advance by an experiment or the like.

It is preferable that the series of the operation of the two ACMs10are operations that can preferably absorb the roll vibration generated in the engine2(seeFIG. 1A).

Programs executed by the ACM ECU62are configured such that the series of the operation of the two ACMs10(seeFIG. 1A) set as described above is realized by the control of the ACMECU62(seeFIG. 4).

By making the ACM ECU62to execute the programs configured as described above at the start time of the engine2(seeFIG. 1A), the roll vibration generated at the start time of the engine2can be always absorbed preferably by the two ACMs10.

As shown inFIG. 7, the ACM ECU62(seeFIG. 4) may receive a signal notifying the start of the electrical motor4(start signal) at a time t3which is delayed by a delay time period ΔT3from the time t0when the ignition switch (not shown) is turned on to start the electrical motor4(seeFIG. 1A).

In this case, a time period ΔT4from the time t3when the ACM ECU62receives the start signal to the time t1when the control of the two ACMs10(seeFIG. 1A) is started may be a time period which is obtained by deducing from the rise time period ΔT1the delay time period ΔT3which is from the time t0when the electrical motor4is started to the time t3when the ACM ECU62receives the start signal.

It may be configured that the control of the two ACMs10(seeFIG. 1A) is started when the time period ΔT4has passed since the time when the ACM ECU62(seeFIG. 4) received the start signal.

By configuring as above, the ACM ECU62can start to control the two ACMs10at the time t1when the roll vibration is generated in the engine2(seeFIG. 1A).

The start signal is, for example, a signal notifying that the engine ECU61(seeFIG. 4) starts to drive the electrical motor4(seeFIG. 1A). It may be configured that the start signal is transmitted to the ACM ECU62(seeFIG. 4) through a communication line (not shown).

In this configuration, the delay time period ΔT3may be generated as a time period required for the communication.

The delay time period ΔT3, however, can be calculated by an experiment in advance, and programs for realizing the operation of the two ACMs10(seeFIG. 1A) from the time t0when the ignition switch (not shown) is turned on to the time t2when the roll vibration time period ΔT2has been finished can be configured taking the delay time period ΔT3into consideration.

More specifically, the time period ΔT4is set which is calculated by deducing the delay time period ΔT3obtained by an experiment or the like in advance from the rise time ΔT1set in advance.

Programs can be configured such that the ACM ECU62(seeFIG. 4) starts to control the two ACMs10(seeFIG. 1A) when the time period ΔT4has passed since the ACM ECU62received the start signal.

By making the ACM ECU62(seeFIG. 4) to execute the programs configured as described above, it is possible to start the control of the two ACMs10(seeFIG. 1A) at the time t1when the roll vibration starts. This enables to preferably absorb the roll vibration generated in the engine2(seeFIG. 1A).

Furthermore, if the hybrid vehicle V (seeFIG. 1A) has an idle reduction function, the active vibration damping support device1according to the embodiment can absorb with the two ACMs10(seeFIG. 1A) the roll vibration generated when the engine2(seeFIG. 1A) is restarted which has been stopped by the idle reduction function, whereby the transmission of the roll vibration to the vehicle body frame F (seeFIG. 2) can be suppressed.

In this case, for example, it is configured that the engine ECU61(seeFIG. 4) inputs to the ACM ECU62(seeFIG. 4) a signal (a restart signal) which is for starting the electrical motor4(seeFIG. 1A) to restart the engine2(seeFIG. 1A).

By making the ACM ECU62to control the two ACMs10(seeFIG. 1A), taking the time when the restart signal is input as the time t3shown inFIG. 7, the roll vibration generated at the restart time of the engine2can be absorbed in the two ACMs10.

As described above, in the active vibration damping support device1(seeFIG. 1A) according to the embodiment, the ACM ECU62(seeFIG. 4) can accurately predict the time taken until the roll vibration comes to an end since the time when the engine2(seeFIG. 1A) is started, the magnitude of the roll vibration and the cycle of the roll vibration. As the ACM ECU62controls the two ACMs10based on the magnitude of the roll vibration Xr, the roll vibration period ΔT2and the cycle Tr of the roll vibration, there is an advantage that the roll vibration generated at the start time of the engine2can be absorbed by the two ACMs10and the transmission of the roll vibration to the vehicle body frame F (seeFIG. 2) can be preferably suppressed.

Especially, the engine2(seeFIG. 1A) is stopped and restarted frequently if the hybrid vehicle V (seeFIG. 1A) has an idle reduction function. Therefore, if the roll vibration is transmitted to the vehicle body frame F (seeFIG. 2), a driver may feel uncomfortable.

As the active vibration damping support device1(seeFIG. 1A) according to the embodiment can preferably suppress the transmission of the roll vibration generated in the engine2to the vehicle body frame F, there is an excellent advantage that uncomfortability felt by a driver can be significantly reduced even in the hybrid vehicle V having an idle reduction function.

Without limited to a hybrid vehicle, the present invention may be applied to any vehicle which includes as a cell motor a motor that can output torque large enough to rotate the crankshaft of an engine and set the rotation speed of the engine in advance.

DESCRIPTION OF THE REFERENCE NUMERALS