KR101378652B1 - Device and method for controlling a bearing element - Google Patents

Abstract

The invention relates to a control device (RE) for controlling an assembly in a vehicle, in particular a bearing member (VLE) for the support of an engine and / or a transmission. The bearing member VLE includes a chamber 104 containing a magnetorheological fluid, a coil 106 for generating a magnetic field in the chamber 104, and a pressure sensor 118 for measuring the hydraulic pressure in the chamber 104. do. The control device includes a pressure detection unit 202 for periodically detecting the pressure measurement measured by the pressure sensor 118, a calculation unit 204 for calculating the rate of pressure change using two or more pressure measurement values, And a switch unit 208 that switches on the control current through the coil 106 depending on whether the rate of change exceeds the threshold.

Bearing member, control unit, chamber, pressure sensor, pressure detection unit

Description

DEVICE AND METHOD FOR CONTROLLING A BEARING ELEMENT}

The present invention relates to a control device and a control method of a bearing member for supporting an assembly in a vehicle, in particular an engine and / or a transmission.

In EP 1 258 650 A2 a hydraulic bearing member is known which comprises an operating chamber and a compensation chamber, in which magnetorheological fluids are mutually movable. Between the working chamber and the compensation chamber is provided a valve plate which can be closed (switched-on of current / magnetic field) or opened (switched-off of current / magnetic field) by an electrically controllable magnetic coil. Therefore, the rigidity and damping force can be controlled by closing and opening the valve plate as intended according to the bearing motion.

For the control of such bearing members, conventional sensors are used which detect parameters such as position or speed, for example via a mechanical sensor arm. It is also known from US 2006-0173592 to use a sensor to measure the hydraulic pressure in the hydraulic bearing member.

In addition, US 2006-0173592 discloses a control system and a control method for controlling a hydraulic bearing member used for supporting an assembly, in which the assembly and the frame are fixed by a bearing member. The movement state of the bearing member is detected through the acceleration sensors respectively installed in the. However, apart from the bearing member, this type of device has a complex assembly structure, since the sensors must be fixed and wired in distributed positions. In addition, there may be a delay that prevents the system from quickly reacting between the time a force occurs in the bearing members and the time the acceleration caused by the force is recorded.

It is an object of the present invention to provide an improved control device and an improved control method for the control of an assembly in a vehicle, in particular a bearing member for supporting an engine and / or a transmission, wherein the control of the bearing member is simple and cost-effective. It must be performed by the device.

In the case of a control device according to the invention for the control of an assembly in a vehicle, in particular a bearing member for supporting an engine and / or a transmission, according to claim 1 and a corresponding control method according to claim 10. This has the advantage of being controlled and involving a very short delay in response to the vibration of the assembly. In addition, as the sensor forms a unit with the bearing member, it is particularly advantageous in terms of cost, robust and easy to maintain, in which the required space for the sensor is reduced and the separate assembly of the sensor and the corresponding supply lines is omitted. The structure can be achieved. In addition, since no mechanical parts are needed between the assembly and the vehicle frame, the formation of a noise transmission path is prevented.

The basic concept of the present invention is to use a pressure sensor fixed to the bearing member itself, which measures the pressure of the magnetorheological fluid in the working chamber of the bearing member, for the control of the bearing member, each one from two or more pressure measurements. The rate of pressure change is obtained.

If the rate of change exceeds a preset threshold, likewise the preset control current is transmitted through the coil of the bearing member, thus preventing fluid flow from the working chamber of the bearing member into the compensation chamber, and a large resistance inhibits the compression movement. The control current is not switched on in the depressurization stage and near the kinetic inversion point between the compression stage and the decompression stage, since the rate of change is below the preset threshold.

In this way, since the face surrounded by the force-displacement-curve of the assembly motion is maximized, the maximum damping of the assembly vibration is achieved.

The dependent claims present preferred developments and examples of the subject matter of the present invention.

According to one preferred embodiment the control device comprises a parameter adjusting unit which dynamically adjusts the control current and / or the threshold value respectively in accordance with a preset functional relationship of the detected pressure measurements. In this case, the control device preferably comprises a reference pressure unit which detects and stores the hydraulic pressure in the working chamber as a reference pressure when the assembly is at rest, wherein the preset function relationship is for each of the periodically detected pressure measurements and the reference pressure. It is a functional relationship with the difference between

According to a further preferred embodiment, the control device comprises an operating state determining device for dynamically determining the operating state of one of a plurality of different operating states of the vehicle, wherein the parameter adjusting unit is respectively adapted to control current and / or according to the operating state. Or select a function relationship of the threshold value from one of a corresponding plurality of preset function relationships.

Embodiments of the invention are shown in the drawings and described in more detail below.

Identical reference numerals denote identical or functionally identical members.

1 is a simplified longitudinal cross-sectional view of a magnetorheological fluid bearing member with a pressure sensor, in accordance with an embodiment of the present invention.

2 is a logic block circuit diagram of a control device according to an embodiment of the present invention.

3 is a logic block circuit diagram of a control device according to a further embodiment of the present invention.

4 is a flowchart of a control method according to an embodiment of the present invention.

5 shows an exemplary behavior over time of the pressure in the working chamber of the magnetorheological fluid bearing member according to one embodiment of the invention, and the time of control current switched by the control device according to one embodiment of the invention. Exemplary behavior is a graph associated with each other.

Figure 1 shows a simplified longitudinal sectional view of a magnetorheological fluid bearing member with a pressure sensor used in accordance with one embodiment of the present invention for controlling the bearing member.

The bearing member VLE includes an operation chamber 104 and a compensation chamber 102 inside the housing, and the magnetorheological fluid is movable between the chambers. Between the working chamber 104 and the compensation chamber 102, for example, three openings 112, for example, in the form of a gap, acting as a passage for fluid movement between the chambers 104, 102, In the direction is provided a partition wall or plate 125.

For example, along the periphery of the dividing wall formed of the plate 125, a coil 106 is crimped through which the control current can be introduced through the electrical terminal 120. When the control current flows, a magnetic field for increasing the flow resistance of the magnetorheological fluid is formed in the gap-shaped opening 112 bounded by the iron core 114 to increase the flow resistance of the magnetorheological fluid. Flow may be interrupted or completely blocked.

The pressure sensor fixing device 116 is provided with a pressure sensor 118 which is provided with a pressure sensor 118 for supplying a measurement signal corresponding to the pressure in the working chamber 104 via the electrical connection 122. . In a preferred manner, the pressure sensor measures on the one hand the point where the magnetic field of the coil 106 does not affect the connection between the pressure sensor and the working chamber, on the other hand, where the terminal 120 of the coil 106 is also located. Installed so that the signal can be reduced.

The working chamber 104 is also bounded by an elastic outer wall 108, for example a rubber-metal-part, to which the threaded rod 110 is fixed. The compensation chamber 102 is likewise bounded by an elastic diaphragm 124, for example made of elastomeric material. Preferably between the cover 126 and diaphragm 124 of the bearing member VLE may be pressurized to aid in fluid reflux from the compensation chamber 102 into the working chamber 104 in the depressurization stage.

During operation, the bearing member is assembled such that, for example, the assembly to be supported is connected with the threaded rod 110 and the housing of the bearing member VLE is connected with the frame of the vehicle. When the assembly applies pressure to the bearing member VLE through the threaded rod 110, the fluid is pressurized from the working chamber 104 into the compensation chamber 102, whereby the diaphragm 124 is elastically stretched by the fluid. . When the control current is guided through the coil 106, the damping force and stiffness of the bearing member can be controlled through intentional variations in flow resistance in the openings 112 in the form of gaps.

2 shows a logic block circuit diagram of a control device RE according to an embodiment of the invention. On the left side of the drawing, the bearing member VLE illustrated in FIG. 1 is reduced and schematically illustrated. The pressure sensor 118 is connected with the pressure detection unit 202 of the control device RE to supply a pressure measurement signal indicative of the pressure in the working chamber of the bearing member. The coil 106 of the bearing member VLE is connected with a switch unit 208 that switches a control current through the coil.

Within the signal flow between the pressure detection unit 202 and the switch unit 208 is a calculation unit 204 and a low pass filter 206. The pressure detection unit 202 is also connected with the reference pressure unit 212 and the parameter adjustment unit 210 to provide a measurement of the pressure in the working chamber of the bearing member VLE to these units and the calculation unit 204 as well. do. The parameter adjusting unit 210 adjusts the parameter, and according to the parameter, the switch unit 208 switches the control current through the coil.

During operation, the pressure detection unit 202 dynamically measures the pressure in the working chamber of the bearing member VLE. The calculating unit 204 receives the measured value and uses this measured value to similarly dynamically calculate the rate of pressure change, for example to form a difference between the measured values measured by the calculating unit periodically in two successive times. By dividing by the duration of the cycle. The resulting signal indicative of the rate of change as a function of time is supplied to a low pass filter 206 which only passes frequencies below a preset cutoff frequency. The signal obtained by the low pass filtering switches the control current through the coil 106 by comparing the amplitude of the signal with a preset threshold, which also has a preset intensity when the amplitude of the low pass filtered rate of change signal exceeds the threshold. -Is supplied to the switch unit 208 to switch off when the amplitude is below the threshold.

During operation, when the reference pressure unit 212 confirms that the assembly is stationary, so that the control current through the coil 106 is switched off, the reference pressure unit is subject to pressure in the compensation chamber due to the connection opened to the compensation chamber. The measurement of the pressure in the corresponding working chamber is detected via the pressure detection unit 202 and stored as a reference pressure.

When the assembly is operating, ie not stationary, the reference pressure unit 212 provides the stored reference pressure to the parameter adjustment unit 210. At the same time, the parameter unit 210 receives the periodically detected pressure measurement from the pressure detection unit and similarly calculates the gauge pressure periodically by subtracting the reference pressure from each of the periodically detected measurements. Based on the gauge pressure periodically detected, the parameter adjusting unit 210 periodically adjusts the preset intensity and / or the preset threshold of the control current to be switched through the switch unit 208, The preset intensity and / or preset threshold influences as a parameter the current supplied from the switch unit 208 to the coil 106. To this end, for example, tables may be stored in the parameter adjustment unit 210 which respectively assign the possible values of the threshold to be adjusted and / or the value of the control current to possible gauge pressure values.

3 shows a logic block circuit diagram of a control device according to a further embodiment of the present invention. In this embodiment, the structure of the control device RE already described with reference to FIG. 2 is assumed, which is shown as a simple rectangular blank in this figure. In addition, in the case of FIG. 2, in this embodiment, a plurality of bearing members VLE1... VLEn are controlled, and for this purpose, the members of the control device RE shown in FIG. The fact is that it is quite general.

In FIG. 3, reference numerals S1, S2,..., Sn denote, for example, a speed sensor, a brake sensor, an engine speed sensor, a steering angle sensor, a clutch sensor, a vertical acceleration sensor, a horizontal acceleration sensor, a wheel speed sensor, A plurality of sensors for setting unique parameters for each vehicle operating state, such as an accelerator pedal sensor, are displayed.

In addition, reference numerals ST1, ST2, ..., STn denote control devices in respective operating states unique to the operating states, in particular determined by the signal values of the sensors S1, S2, ..., Sn. do.

In the above example, not only the sensors S1, S2, ..., Sn, but also the control devices ST1, ST2, ..., STn communicate in both directions with a data bus CB such as, for example, a canvas CANbus. can do.

Reference numeral SES denotes sensors S1, S2, ..., Sn and control devices ST1, ST2, ..., which can be supplied from the data bus CB to the operating state recognition device SES. A plurality of operating state recognition blocks (40) for recognizing a plurality of different vehicle operating states on the basis of input signals unique to each of the operating states of STn, and for supplying corresponding corresponding operating state output signals B1, B2, B3, B4; The operation state recognition device with E1, E2, E3, E4) is displayed.

In this embodiment, the operating state recognition device SES can detect four different operating states and supply four operating state recognition blocks E1, E2 that supply corresponding operating state output signals B1, B2, B3, B4. , E3, E4, ie a first operating state recognition block E1 for recognizing one or more traction operating states and a second operating state recognition block for recognizing one or more handling operating states ( E2), a third operating state recognition block E3 for recognizing one or more comfortable driving operating states, and a fourth operating state recognition block E4 for recognizing one or more noise generating operating states.

Priority setting device PR continuously receives corresponding output signals B1, B2, B3, B4 of operating state recognition blocks E1, E2, E3, E4, bearings according to a preset and stored priority assignment The operating state related to the adjustment is determined to send an operating state signal PB having a corresponding priority.

The reference sign PF also determines an adjustment parameter set EPS1 ... EPSn for the corresponding bearing member VLE1 ... VLEn, based on the output signal PB of the priority setting device PR. Display the device to determine the parameters. The adjustment parameter sets EPS1 ... EPSn may be stored in the parameter determining device PF or calculated according to an algorithm preset by the parameter determining device.

If the structure of the control device RE shown in Fig. 2 is assumed, for example the cutoff frequency of the low pass filter is adjustable according to the operating state, the vibration frequencies occurring in one set operating state are attenuated as intended. . The reference pressure stored in the reference pressure unit may also be changed, for example in view of the changed position of the assembly in the set operating state. The tables stored in the parameter adjusting unit, which pre-assigns a given gauge pressure to threshold and / or control current values, are likewise changed depending on the operating state, for example by accessing different tables in different operating states.

The parameter determining device PF can also be supplied with a mode signal MS for consideration in the determination of the adjustment parameter sets EPS1... EPSn. As such, the set of adjustment parameters EPS1 ... EPSn is additionally changed depending on the current operating state, for example speed, preselected program, excitation state and the like. For example, in the set operating state, the threshold and / or control current values detected by the parameter adjusting unit of the table, or the cutoff frequency of the low pass filter can be changed through suitable arithmetic operations in accordance with the running speed.

In this example the control device RE comprises a regulating device designed to regulate the control current to be applied to the bearing members VLE1... VLEn. The control device RE supplies the corresponding control current signals SS1 ... SSn to the bearing members VLE1 ... VLEn, and the pressure measurement signal WS1 supplied via the corresponding pressure sensors 31 ... 3n. In addition to ... WSn, the corresponding actual control current signals IS1 ... ISn are received from the bearing members VLE1 ... VLEn.

4 is a flowchart of a control method according to an embodiment of the present invention. The process shown corresponds to an operation performed during one cycle and is repeated continuously. In decision step 400 it is checked whether the assembly is stationary, i.e. the vehicle is in a stationary or equivalent state. In the quiescent state, in step 402 the pressure value p0 is detected and stored as the reference pressure and the control current is set to zero to allow free compensation flow of the magnetorheological fluid between the chambers in step 404. do.

If the assembly is not stationary, in step 406 the pressure measurement value p (n) detected in the current cycle and at least the pressure measurement value p (n-1) detected in the previous cycle is determined. The pressure change over the time interval of the cycle is calculated. This calculated value, together with the corresponding values calculated in previous cycles, forms a time dependent signal to be lowpass filtered in step 408. In this case the cutoff frequency may depend on the currently determined operating state.

In step 410 the gauge pressure is calculated by subtracting the reference pressure p0 from the pressure measurement p detected in the ongoing cycle. This gauge pressure is used in step 412 to find the corresponding threshold, for example in the table. In this case, the table may be selected corresponding to the operating state currently determined from the plurality of tables.

In decision step 414 it is checked whether the currently determined operating state characterizes the parameter according to the speed. If characterized, in step 416 the threshold value detected from the table is compensated for, for example according to a preset calculation rule, corresponding to the current value of the travel speed.

In decision step 418, it is determined in step 406 whether the low-pass filtered pressure change is greater than the threshold in step 408. If greater than the threshold, in step 420 the control current to be sent to the bearing member is detected, for example from a preset table. In this case, the table may be selected corresponding to the operating state currently determined from the plurality of tables. The control current can also be changed using, for example, traveling speed or similar additional parameters in certain operating states.

If the pressure change does not exceed the threshold, the control current is set to the prescribed minimum value. This measure allows the fluid to be freely refluxed from the compensation chamber 102 into the working chamber 104 when the pressure of the assembly applied to the bearing member is reduced during the restoring vibration phase. Reflux may advantageously be supported through pressurization of the compensation chamber 102.

5 shows an exemplary behavior 504 over time of the pressure in the working chamber of a magnetorheological fluid bearing member according to one embodiment of the present invention, and the control current switched by the control device according to one embodiment of the present invention. A graph is shown in which exemplary behavior 506 over time is associated with each other. The graph includes a time axis 500. The other axis is used to indicate the control current 506 and the pressure 504 in any unit. It can be clearly seen that the control current 504 is switched on at all times when the rate of pressure change, ie, the slope of the curve 504 of FIG. 5, exceeds a defined threshold. Since the threshold is positive in the graph, the control current remains in the switch-off state not only during the restoring oscillation phase but also when the oscillation is located near the motion inversion point.

The following reference numerals are used in the drawings showing an embodiment of the present invention.

11 ... 1n: Damping force

21 ... 2n: rigidity

31 ... 3n: pressure sensor

102: compensation chamber

104: working chamber

106: magnetic coil

108: elastic outer wall

110: threaded rod

112: gap

114: iron core

116: pressure sensor fixing device

118: pressure sensor

120: terminal for magnetic coil

122: terminal for pressure sensor

124: diaphragm

125: plate

126: cover

202: pressure detection unit

204: calculation unit

206: low pass filter

208: switch unit

210: parameter adjustment unit

212 reference pressure unit

400: Is it stationary?

402: reference pressure detection

404: control current switch-off

406: pressure variation calculation

408: Low pass filtering of pressure variation

410: gauge pressure calculation

412: threshold investigation

414: Is speed dependent?

416: Computation of the compensated threshold

418: Is the pressure change greater than the threshold value?

420: control current detection

422: control current switch-off

500: time base

502: pressure shaft or control current shaft

504: Pressure behavior in the working chamber

506 control current behavior

B1 ... B4: Operating status signal

CB: data bus

E1 ... E4: Operation state recognition block

EPS1 ... EPSn: Adjustable Parameter Set

FS1 ... FSn: Actual current value

MS: mode signal

PB: Prioritized Operating Status Signal

PF: parameter determination device

PR: Priority setting device

RE: control unit

S1 ... Sn: Operating State Sensor

SES: operation state recognition device

SS1 ... SSn: Set current value

ST1 ... STn: control unit

VLE1 ... VLEn: Adjustable hydraulic bearing member

WS1 ... WSn: Pressure Signals

Claims (19)

A control device RE for controlling a bearing member VLE for supporting an assembly in a vehicle, wherein the bearing member VLE includes a chamber 104 containing a magnetorheological fluid and a coil for generating a magnetic field in the chamber. 106, and a pressure sensor 118 for measuring the hydraulic pressure in the chamber, A pressure detection unit 202 for periodically detecting a pressure measurement measured by the pressure sensor, A calculation unit 204 for calculating the rate of pressure change using two or more pressure measurements, A switch unit 208 that switches on or off the control current through the coil 106 depending on whether the rate of change exceeds the threshold, A parameter adjusting unit 210 is provided which periodically adjusts either or both of the control current and the threshold value in accordance with a preset function relationship of the detected pressure measurements, An operating state determining device PR is provided for periodically determining an operating state of one of a plurality of different operating states of the vehicle, and the parameter adjusting unit 210 is configured to either one of a control current and a threshold value, respectively, depending on the operating state or And to select both of the functional relationships from one of the corresponding plurality of preset functional relationships. delete A reference pressure unit 212 is provided for detecting and storing the hydraulic pressure in the chamber 104 as a reference pressure when the vehicle is stationary, wherein the preset function relationship is for each of the dynamically detected pressure measurements. And a function relation of the difference between the reference pressure and the reference pressure. delete The method of claim 1, wherein the plurality of different operating states includes one or more operating states associated with speed, and the parameter adjusting unit 210 sets either or both of the control current and the threshold in the operating states associated with the speed. A control device for a bearing member, configured to vary corresponding to a running speed of a vehicle. 2. The control device of claim 1, wherein the reference pressure unit (212) is configured to change the stored reference pressure in accordance with the operating state. 4. A control device for a bearing member according to claim 1 or 3, characterized in that a low pass filter unit (206) is provided for low pass filtering the behavior over time of the rate of change. 2. A variable low pass filter unit 206 is provided which low-pass filters the behavior of the rate of change over time, the low pass filter unit having a variable cutoff frequency dependent on the operating state, Control device of the bearing member. A system for supporting an assembly in a vehicle, One or more bearing members VLE1... VLEn comprising a chamber 104 containing a magnetorheological fluid, A pressure sensor 118 fixed to one or more bearing members to measure the pressure of the magnetorheological fluid in the chamber, System with a control device (RE) for controlling at least one bearing member according to claim 1. A method of controlling a magnetorheological fluid assembly bearing (VLE) having a chamber 104 containing a magnetorheological fluid, Measuring the first and second measurements of the pressure in the chamber at intervals of time; Calculating (406) the rate of pressure change from the amount of change in the second measured value relative to the first measured value during the time interval; If the rate of change exceeds the threshold, a step 420 in which the control current supplied to the bearing member is switched on or switched off, The pressure is measured periodically, and periodically or between one or both of the threshold value 412 and the control current 404 according to the periodically detected pressure measurement and the respective predetermined function relationship of the threshold value or the control current. Additional steps are provided, Measuring (402) the pressure in the chamber of the assembly bearing when the assembly is stationary; Storing the measured pressure as a reference pressure, Further provided is a step 410 of periodically calculating the gauge pressure as the difference between the periodically detected pressure measurements and the reference pressure, The predetermined function relationship of either or both of the threshold value and the control current is each a function relationship with the calculated gauge pressure. 11. The method of claim 10, wherein two or more measurements are measured and used to calculate (406) the rate of pressure change. 12. A method according to claim 10 or 11, characterized in that the calculation (406) of the rate of pressure change over a plurality of time intervals is performed. delete delete The method of claim 10, further comprising: recognizing a plurality of different vehicle operating states according to signals unique to each of the operating states, Periodically determining a vehicle operating state related to bearing adjustment according to a preset priority assignment; And based on an operating state associated with the bearing adjustment, further selecting each of the functional relationship of the control current and the threshold or both from one of the corresponding plurality of preset functional relationships. Control method. The method of claim 15, wherein the plurality of different operating states includes one or more operating states with respect to speed, Confirming whether the operating state related to the bearing adjustment is the operating state related to the speed (414); And when the operating state related to the bearing adjustment is the operating state related to the speed, either or both of the control current and the threshold value are changed corresponding to the traveling speed of the vehicle. The method of claim 15, wherein the plurality of different operating states includes one or more operating states associated with the assembly location, and Confirming that the operating state related to the bearing adjustment is the operating state related to the assembly position; And wherein the stored reference pressure is deformed when the operating state associated with the bearing adjustment is the operating state associated with the assembly position. 12. The control method according to claim 10 or 11, wherein the pressure is measured periodically and the rate of change is low pass filtered (408) as a function of time. 16. The method of claim 15, further comprising the step of low pass filtering the behavior over time of the rate of change, wherein the low pass filtering is performed by a cutoff frequency that depends on the operating conditions associated with the bearing adjustment.

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