Engine mount control device and control method

Abstract

To suppress vibration in consideration of an influence on a crank shaft of an engine from outside the engine.SOLUTION: An engine mount control device is provided between an engine and a vehicle body to support the engine, and suppresses vibration transmitted from the engine to the vehicle body. The engine mount comprises a passive vibration damping mechanism for passively suppressing the vibration and, in addition, an active vibration damping mechanism for actively suppressing the vibration. The control device comprises: a sensor for outputting a signal showing an amount or a value detected about an index for determining an increase or a decrease in inertia which has an influence on a crank shaft of the engine from outside; and an ECU. The ECU uses a relationship shown in Fig. 5 to use the amount or the value shown by the signal from the sensor, thereby determining the increase or the decrease in the inertia. The ECU calculates a control value for changing damping characteristics of the active mechanism in response to the determined increase or decrease in the inertia, and uses the calculated control value to control the active vibration damping mechanism.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a control device and control method for an engine mount, and more particularly to a control device for an engine mount that is provided between an engine and a vehicle body and supports the engine while suppressing vibrations transmitted from the engine to the vehicle body, and a control method using the control device. [Background technology]

[0002] Conventionally, there have been active engine mounts that are controlled according to vehicle conditions such as vehicle speed, door opening / closing, hood opening / closing, remaining fuel, passenger status, load weight, or battery voltage (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 9-319380 Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology of Patent Document 1, the vehicle state is used to suppress divergence of the control of the engine mount. However, the technology of Patent Document 1 does not take into consideration vibrations that affect the engine crankshaft from the outside.

[0005] This disclosure has been made to solve the above-mentioned problems, and its purpose is to provide an engine mount control device and control method that are capable of suppressing vibration by taking into account external influences on the engine crankshaft. [Means for solving the problem]

[0006] The engine mount control device according to the present disclosure is an engine mount control device that is provided between an engine and a vehicle body, supports the engine, and suppresses vibrations transmitted from the engine to the vehicle body. The engine mount includes an active mechanism that actively suppresses vibrations in addition to a passive mechanism that passively suppresses vibrations. The control device includes a sensor that outputs a signal indicating a detected amount or value of an index for identifying an increase or decrease in inertia that externally affects the engine crankshaft, and a processor. The processor identifies the increase or decrease in inertia using the amount or value indicated by the signal from the sensor, calculates a control value that changes the damping characteristics of the active mechanism according to the identified increase or decrease in inertia, and controls the active mechanism using the calculated control value.

[0007] Preferably, the damping characteristic is a spring constant or a damping coefficient. Preferably, the processor determines the increase or decrease in inertia using a load state on the vehicle body. Preferably, the processor determines the increase or decrease in inertia using a change in acceleration applied to the vehicle body due to going uphill or downhill.

[0008] According to another aspect of the disclosure, a control method for an engine mount is a control method by a control device for an engine mount that is provided between an engine and a vehicle body, supports the engine, and suppresses vibrations transmitted from the engine to the vehicle body. The engine mount includes an active mechanism that actively suppresses vibrations in addition to a passive mechanism that passively suppresses vibrations. The control device includes a sensor that outputs a signal indicating a detected amount or value of an index for identifying an increase or decrease in inertia that externally affects the crankshaft of the engine, and a processor. The control method includes the steps of: identifying the increase or decrease in inertia by using the amount or value indicated by the signal from the sensor; calculating a control value that changes the damping characteristic of the active mechanism in response to the identified increase or decrease in inertia; and controlling the active mechanism by using the calculated control value. Effect of the Invention

[0009] According to this disclosure, it is possible to provide a control device and a control method for an engine mount that is capable of suppressing vibration by taking into account external influences on the engine crankshaft. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic diagram showing a state in which an engine mount according to an embodiment of the present disclosure is attached to a vehicle. [Diagram 2] 2 is a block diagram showing an outline of a configuration for controlling the engine mount according to the embodiment; FIG. [Diagram 3] 5 is a diagram for explaining vibration transmitted from the engine to the vehicle body in this embodiment. FIG. [Figure 4] 4 is a flowchart showing a flow of a control process for the engine mount according to the embodiment. [Diagram 5] 4 is a graph showing the relationship between various inertia and the inertia for identifying the inertia of the vehicle body in this embodiment. [Figure 6] 1 is a diagram showing the configuration of an engine mount according to an application example of the present disclosure. FIG. [Figure 7] 1 is a block diagram showing a configuration of a control device for an engine mount according to an application example of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, the same components are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

[0012] Fig. 1 is a schematic diagram showing an engine mount 20 according to an embodiment of the present disclosure attached to a vehicle 1. Fig. 2 is a block diagram showing an outline of a configuration for controlling the engine mount 20 according to the embodiment. With reference to Figs. 1 and 2, the vehicle 1 includes a vehicle body 2, an engine 10, a drive system 11, a drive shaft 12, tires 13, an active engine mount 20, and an ECU (Electronic Control Unit) 100 that controls the engine mount 20.

[0013] The engine 10 may be any drive source capable of generating power, for example an internal combustion engine that uses gasoline or methanol as fuel, and transmits power to a drivetrain 11 via a crankshaft and a flywheel. The drivetrain 11 transmits the power transmitted from the engine 10 to a driveshaft 12. The driveshaft 12 transmits the power transmitted from the drivetrain 11 to tires 13. The tires 13 transmit the power transmitted from the driveshaft 12 to the road surface. This enables the vehicle 1 to travel.

[0014] The engine mount 20 includes a passive vibration damping mechanism 22 that passively damps vibrations transmitted between the engine 10 and the vehicle body 2, and an active vibration damping mechanism 21 that actively damps the vibrations. The passive vibration damping mechanism 22 is, for example, made of rubber, or rubber plus a pair of liquid-sealed chambers that communicate with each other through an orifice. The active vibration damping mechanism 21 is, for example, made of an air chamber with variable pressure. The engine mount 20 is attached between the vehicle body 2 and the engine 10, and supports the engine 10 while damping vibrations transmitted from the engine 10 to the vehicle body 2. This makes it possible to improve the ride comfort by damping vibrations transmitted to the passengers of the vehicle 1, and to prevent deterioration of the vehicle body 2 due to excessive vibrations transmitted to the vehicle body 2.

[0015] The ECU 100 includes a CPU (Central Processing Unit) 110 as a processor, and a memory 120 as a storage unit. The memory 120 includes a RAM (Random Access Memory) and a ROM (Read Only Memory), and stores programs and data used by the CPU 110. The CPU 110 executes predetermined processing defined by a program in accordance with the programs and data stored in the memory 120 and data input from the outside, and stores data resulting from the execution in the memory 120 or outputs it to the outside.

[0016] 3 is a diagram for explaining vibrations transmitted from the engine 10 to the vehicle body 2 in this embodiment. Referring to FIG. 3, the rotation speed of the engine changes over time, causing rotation fluctuations as shown in the diagram. The thick line in the graph indicates the average rotation fluctuations caused by driving. Small rotation fluctuations caused by the combustion cycle of the engine 10 become a vibration source, and vibrations are transmitted to passengers in the cabin of the vehicle body 2.

[0017] In the prior art, in controlling the engine mount 20, no consideration was given to vibrations that affect the crankshaft of the engine 10 from the outside.

[0018] Therefore, the control device 30 of the engine mount 20 includes a sensor (vehicle body inertia specifying unit 200, described later) that outputs a signal indicating a detected amount or value of an index for specifying an increase or decrease in inertia that externally affects the crankshaft of the engine 10, and an ECU 100. The ECU 100 specifies the increase or decrease in inertia using the amount or value indicated by the signal from the sensor, calculates a control value for changing the damping characteristics of the active vibration damping mechanism 21 in accordance with the specified increase or decrease in inertia, and controls the active vibration damping mechanism 21 using the calculated control value.

[0019] This makes it possible to suppress vibrations by taking into account external influences on the crankshaft of the engine 10.

[0020] 2 again, the vehicle body inertia specification unit 200 includes sensors that output signals indicating detected quantities or values ​​of indices for specifying an increase or decrease in inertia externally affecting the crankshaft of the engine 10, such as an acceleration sensor that detects six-axis inertial forces including the accelerations of three axes (front-rear, left-right, up-down) of the vehicle body 2 and the angular velocities of these three axes, an accelerator opening sensor, a shift position sensor, and a vehicle speed sensor. The inertia of the vehicle body 2 is the degree of difficulty in turning and moving the vehicle body 2, and specifically refers to the moment of inertia and / or the inertial mass of the vehicle body 2.

[0021] Fig. 4 is a flowchart showing the flow of control processing for engine mount 20 according to this embodiment. Referring to Fig. 4, a program for this control processing is stored in memory 120 of ECU 100. This program for the control processing is called from a higher-level process and executed by CPU 110 of ECU 100 at predetermined intervals.

[0022] First, the CPU 110 of the ECU 100 calculates the inertia of the vehicle body 2 using a signal from the vehicle body inertia specifying unit 200 (step S111).

[0023] The minute rotational fluctuations caused by the combustion cycle of engine 10 shown in Fig. 3 change depending on the inertia applied from outside to the crankshaft of engine 10. Specifically, as the inertia increases, the rotational fluctuations also increase. The inertia applied from outside to the crankshaft is applied to the crankshaft after being multiplied by the gear ratio of the transmission of drivetrain 11, so that the inertia is not the same if the gear is different, even if the size and weight of the vehicle, as well as the vehicle speed, acceleration, loading condition, driving conditions, and road surface conditions, are the same.

[0024] Fig. 5 is a graph showing the relationship between various indices for identifying the inertia of the vehicle body 2 in this embodiment and the inertia. Referring to Fig. 5, the horizontal axis indicates the shift position of the transmission. In the figure, forward 1 to forward 6 are shown as the shift positions. The vertical axis indicates the inertia applied from the outside to the rear end (flywheel side) of the crankshaft of the engine 10.

[0025] Compared to (1) when there is only one passenger and no load, (2) when there is a full load of five passengers on board, the inertia applied from the outside to the rear end of the crankshaft is greater. Compared to (2) when there is a full load of five passengers on board, the inertia applied from the outside to the rear end of the crankshaft is greater in (3) when there is a full load of five passengers on board and also on an uphill road. Also, the higher the gear shift, the greater the inertia applied from the outside to the rear end of the crankshaft.

[0026] Note that FIG. 5 shows examples of some conditions, but for other conditions, data is collected through experiments or simulations, and a table capable of identifying inertia values ​​for various vehicle speeds, accelerations, loading conditions, driving conditions, and road surface conditions is created in advance based on the collected data, and the table is stored in memory 120 of ECU 100.

[0027] Returning to FIG. 4, in step S111, the CPU 110 identifies the vehicle speed, acceleration, loading condition, driving conditions, and road surface conditions, and identifies the inertia corresponding to the identified vehicle speed, acceleration, loading condition, driving conditions, and road surface conditions, using a table showing the relationships as shown in FIG. 5.

[0028] The vehicle speed is determined by the CPU 110 using a signal from a vehicle speed sensor of the vehicle body inertia determination unit 200. The acceleration is determined by the CPU 110 using a signal from an acceleration sensor of the vehicle body inertia determination unit 200. The loading state is determined by the CPU 110 from the degree of change in acceleration relative to the driving force according to the accelerator opening, using a signal from an accelerator opening sensor of the vehicle body inertia determination unit 200. The road surface condition, such as an uphill road or a downhill road, is determined by the CPU 110 using a signal from an acceleration sensor of the vehicle body inertia determination unit 200.

[0029] A seating sensor or a seat belt fastening sensor may be included in the vehicle body inertia specifying unit 200, and a signal from the seating sensor or the seat belt fastening sensor may be used to roughly estimate the weight distribution of the occupants of the vehicle 1. A posture sensor may be included in the vehicle body inertia specifying unit 200, and a signal from the posture sensor may be used to roughly estimate the weight distribution of the load. A navigation system may be included in the vehicle body inertia specifying unit 200, and the road surface conditions, such as an uphill road or a downhill road, may be identified from map data of the navigation system.

[0030] Next, CPU 110 calculates a control value for changing the spring constant and damping coefficient of engine mount 20 according to the inertia calculated in step S111 (step S112). For example, a table capable of identifying the spring constant and damping coefficient corresponding to the inertia is created in advance based on the results of an experiment or simulation. CPU 110 uses this table to calculate the control value for changing the spring constant and damping coefficient from the inertia. Since it is believed that the vibration of engine 10 increases as the inertia increases, the table is created so that the spring constant and damping coefficient increase as the inertia increases.

[0031] Then, the CPU 110 controls the active vibration damping mechanism 21 of the engine mount 20 using the control value calculated in step S112 (step S113).

[0032] [Example of application] The control device 30 and the control method for the engine mount 20 described above can be applied to, for example, the engine mount 20A of Denso Corporation described in Japanese Patent Application Laid-Open No. 2003-214484.

[0033] 6 is a diagram showing the configuration of an engine mount 20A according to an application example of this disclosure. The engine mount 20A includes a mount rubber 201, a disk 202, a bolt 203, a rotation pin 204, a side member 205, a bolt 208, a rotation pin 209, a partition member 214, a rubber membrane member 215, a ring-shaped plate 216, a bolt 217, a rubber membrane member 218, and a bottom member 219.

[0034] The main liquid chamber X is a space closed by the mount rubber 201 and the rubber membrane member 215, and is filled with a non-compressible fluid. The air chamber A is a space closed by the rubber membrane member 215 and the partition member 214. The auxiliary liquid chamber Y is a space closed by the partition member 214 and the rubber membrane member 218, and is filled with a non-compressible fluid. The main liquid chamber X and the auxiliary liquid chamber Y are connected by a throttle flow path Z formed on the outer periphery of the partition member 214. A vibration-damping effect is obtained by passing the non-compressible fluid through the throttle flow path Z between the main liquid chamber X and the auxiliary liquid chamber Y.

[0035] An air passage pipe 210 is connected to the air chamber A. One end of a connecting pipe 211 is connected to the side of the air passage pipe 210 opposite to the air chamber A. The other end of the connecting pipe 211 is branched, and common ports of three ports of a VSVL (low frequency high lift compatible vacuum switching valve) 220 and a VSVH (high frequency low lift compatible vacuum switching valve) 230 are connected to each other.

[0036] The other two ports of VSVL 220 and VSVH 230 are connected to a negative pressure introduction pipe 242 which connects to a negative pressure tank 253 which accumulates negative pressure from a surge tank upstream of an intake manifold 252 of the engine 10 using a check valve, and an air introduction pipe 243 which introduces air (atmospheric pressure) in an intake pipe 251 upstream of a throttle valve through an air cleaner.

[0037] The ECU 100A outputs drive voltages VLout and VHout that respectively control the VSVL 220 and the VSVH 230. This controls the VSVL 220 and the VSVH 230 to be turned ON / OFF, so that atmospheric pressure is introduced into the air chamber A when the control is ON, and negative pressure is introduced into the air chamber A when the control is OFF.

[0038] 7 is a block diagram showing a configuration of a control device 30A for an engine mount 20A according to an application example of the present disclosure. Referring to FIG. 7, the control device 30A includes an ECU 100A, a rotation angle sensor 132, a reference position sensor 133, an A / T range switch 134, an accelerator opening sensor 135, an acceleration sensor 136, an air conditioner switch 137, an air flow meter 138, and a water temperature sensor 139.

[0039] The ECU 100A includes a CPU 110A, a data bus 190, a timer 33, a waveform shaping IC 131, a counter 35, an I / O port 130, an analog input port 38, an A / D conversion circuit 39, a RAM 121, a ROM 122, an I / O port 140, an actuator drive circuit 141, and a power supply circuit 52. When the key switch 51 is turned on, power is supplied from the battery 50 to the power supply circuit 52, and the ECU 100A is started. Drive voltages VLout and VHout for controlling the VSVL 220 and the VSVH 230, respectively, are output from the actuator drive circuit 141. The detailed operation of the engine mount 20A is as described in JP 2003-214484 A.

[0040] The engine mount 20A, the control device 30A, and the ECU 100A in this application example correspond to the engine mount 20, the control device 30, and the ECU 100 shown in Fig. 1 and Fig. 2, respectively. The air chamber A and the air system connected to the air chamber A (VSVL 220, VSVH 230, negative pressure tank 253, etc.) correspond to the active vibration damping mechanism 21 shown in Fig. 2. The mount rubber 201, the main liquid chamber X, the auxiliary liquid chamber Y, and the throttle flow path Z correspond to the passive vibration damping mechanism 22 shown in Fig. 2. The CPU 110A in this application example corresponds to the CPU 110 of the ECU 100 shown in Fig. 2. The RAM 121 and ROM 122 in this application example correspond to the memory 120 of the ECU 100 shown in Fig. 2. The A / T range switch 134, accelerator opening sensor 135, and acceleration sensor 136 in this application example correspond to the shift position sensor, accelerator opening sensor, and acceleration sensor included in the vehicle body inertia identifying unit 200 described in Fig. 2. Due to this correspondence, the control device 30 and control method for the engine mount 20 described above can be applied to the engine mount 20A described in JP 2003-214484 A.

[0041] [Variations] (1) In the above-described embodiment, the inertia corresponding to the vehicle speed, acceleration, loading condition, driving condition and road surface condition is specified using a table capable of specifying the inertia value for each vehicle speed, acceleration, loading condition, driving condition and road surface condition, as shown in Figures 4 and 5. However, without being limited to this, a calculation formula for calculating the inertia corresponding to the vehicle speed, acceleration, loading condition, driving condition and road surface condition may be created in advance using the results of an experiment or simulation, and the inertia may be calculated by substituting the vehicle speed, acceleration, loading condition, driving condition and road surface condition into this calculation formula.

[0042] (2) The above disclosure may be interpreted as a disclosure of the control device 30 of the engine mount 20, as a disclosure of a control method or control program executed by the control device 30 of the engine mount 20, or as a disclosure of the vehicle 1 equipped with the engine mount 20 and the control device 30.

[0043] [summary] (1) As shown in Figures 1 and 2, the control device 30 for the engine mount 20 is disposed between the engine 10 and the vehicle body 2, supports the engine 10, and suppresses vibrations transmitted from the engine 10 to the vehicle body 2. As shown in Figure 2, the engine mount 20 includes an active vibration suppression mechanism 21 that actively suppresses vibrations, in addition to a passive vibration suppression mechanism 22 that passively suppresses vibrations. As shown in Figure 2, the control device 30 includes a sensor that outputs a signal indicating a detected amount or value of an index for identifying an increase or decrease in inertia that externally affects the crankshaft of the engine 10, and an ECU 100. As shown in Figures 4 and 5, ECU 100 identifies an increase or decrease in inertia using the amount or value indicated by the signal from the sensor (for example, step S111), calculates a control value that changes the damping characteristics of the active mechanism in accordance with the identified increase or decrease in inertia (for example, step S112), and controls active vibration damping mechanism 21 using the calculated control value (for example, step S113).

[0044] This makes it possible to suppress vibrations of the crankshaft of the engine 10 while taking into consideration influences from outside the engine 10.

[0045] (2) As shown in Figure 4, the damping characteristic is a spring constant or a damping coefficient, which allows the engine mount 20 to be appropriately controlled.

[0046] (3) As shown in Figures 4 and 5, the ECU 100 determines the increase or decrease in inertia using the loading state of the vehicle body 2. This makes it possible to suppress vibration of the crankshaft of the engine 10 in consideration of the effect of the loading state of the vehicle 1 on the crankshaft of the engine 10.

[0047] (4) As shown in Figures 4 and 5, the ECU 100 identifies an increase or decrease in inertia using a change in acceleration applied to the vehicle body 2 due to going uphill or downhill. This makes it possible to suppress vibrations in the crankshaft of the engine 10, taking into consideration the effect of the change in acceleration applied to the vehicle body 2 due to going uphill or downhill.

[0048] It is also intended that the embodiments disclosed herein may be implemented in appropriate combination. The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present disclosure is indicated by the claims, not by the description of the above-mentioned embodiments, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0049] 1 vehicle, 2 vehicle body, 10 engine, 11 drive system, 12 drive shaft, 13 tire, 20, 20A engine mount, 21 active vibration damping mechanism, 22 passive vibration damping mechanism, 30, 30A control device, 33 timer, 35 counter, 38 analog input port, 39 A / D conversion circuit, 50 battery, 51 key switch, 52 power supply circuit, 100, 100A ECU, 110, 110A CPU, 120 memory, 121 RAM, 122 ROM, 130, 140 I / O port, 132 rotation angle sensor, 133 reference position sensor, 134 A / T range switch, 135 accelerator opening sensor, 136 acceleration sensor, 137 air conditioner switch, 138 air flow meter, 139 water temperature sensor, 141 actuator drive circuit, 190 data bus, 200 Vehicle body inertia specific part, 201 mounting rubber, 202 disc, 203, 208, 217 bolt, 204, 209 rotation pin, 205 side member, 210 air passage pipe, 211 connecting pipe, 214 partition member, 215, 218 rubber membrane member, 216 ring-shaped plate, 219 bottom member, 220 VSVL, 230 VSVH, 242 negative pressure introduction pipe, 243 atmospheric air introduction pipe, 251 intake pipe, 252 intake manifold, 253 negative pressure tank, A air chamber, 131 wave-shaped IC, X main liquid chamber, Y auxiliary liquid chamber, Z throttle flow path.

Claims

1. 1. A control device for an engine mount that is provided between an engine and a vehicle body, supports the engine, and suppresses vibrations transmitted from the engine to the vehicle body, comprising: The engine mount includes an active mechanism that actively suppresses the vibration in addition to a passive mechanism that passively suppresses the vibration, The control device includes: a sensor for outputting a signal indicative of a detected quantity or value of an index for identifying an increase or decrease in inertia caused by an external influence on a crankshaft of the engine; a processor; The processor, determining said increase or decrease in inertia using a quantity or value indicated by a signal from said sensor; calculating a control value for changing a damping characteristic of the active mechanism in response to the specified increase or decrease in the inertia; A control device for an engine mount that controls the active mechanism using the calculated control value.

2. The control device for an engine mount according to claim 1 , wherein the damping characteristic is a spring constant or a damping coefficient.

3. The engine mount control device according to claim 1 or 2, wherein the processor determines the increase or decrease in the inertia using a loading state on the vehicle body.

4. 4. The engine mount control device according to claim 1, wherein the processor determines the increase or decrease in the inertia using a change in acceleration acting on the vehicle body due to ascending or descending a slope.

5. A control method for an engine mount that is provided between an engine and a vehicle body, supports the engine, and suppresses vibrations transmitted from the engine to the vehicle body, the method comprising the steps of: The engine mount includes an active mechanism that actively suppresses the vibration in addition to a passive mechanism that passively suppresses the vibration, The control device includes: a sensor for outputting a signal indicative of a detected quantity or value of an index for identifying an increase or decrease in inertia caused by an external influence on a crankshaft of the engine; a processor; The control method includes the processor: determining said increase or decrease in inertia using a quantity or value indicated by a signal from said sensor; calculating a control value for changing a damping characteristic of the active mechanism in response to the specified increase or decrease in the inertia; and controlling the active mechanism using the calculated control value.

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