KR20050024887A - Variable force solenoid valve drive apparatus of automatic transmission - Google Patents

Abstract

PURPOSE: A VFS driving device of an automatic transmission is provided to supply control convenience and stability of a circuit by executing a high side control using a power terminal and to supply precise self-diagnosis of a VFS V/V(Valve) and control stability by feedback-detecting control current with a sample/hold unit. CONSTITUTION: A VFS driving device of an automatic transmission is composed of a driving signal processing unit(10) for driving a VFS V/V by processing a PWM(Pulse Width Modulation) duty signal output from a transmission control unit; a current detecting unit(20) for detecting the driving current of the VFS V/V and applying a feedback signal to the transmission control unit; and a sample/hold unit(30) for sampling and holding the electric current supplied to the transmission control unit as the feedback signal and then outputting an analog signal.

Description

Variable Force Solenoid Drive in Automatic Transmission {VARIABLE FORCE SOLENOID VALVE DRIVE APPARATUS OF AUTOMATIC TRANSMISSION}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission, and more particularly, high side control using a single power supply is provided in controlling feedback of a variable force solenoid (VFS). The present invention relates to a variable force solenoid driving device of an automatic transmission in which a simple self-diagnosis of a variable force solenoid is performed by providing control simplicity and feedback detection of a control current amount using a sample and a hold. .

Since the VFS performing the duty control in the automatic transmission is driven by the current, the control means feedback-detects the current supplied to the VFS for accurate driving of the VFS, and then controls the amount of current supplied to the VFS accordingly.

As shown in FIG. 2, the variable force solenoid driving device applied to the conventional automatic transmission includes a differential circuit composed of a resistor R6 and a capacitor C4 and an inverter Inv to generate a driving current. A pulse generator 1, a plurality of inverters (Inv1-Inv5), the current amplifier (2) for amplifying the generated driving current at a set ratio, a plurality of diodes (D2-D4) and a capacitor ( C5-C7), a regulator for outputting a VFS V / V drive signal with a current set according to a PWM duty control signal applied from a double voltage unit 3 multiplying the amplified drive current and a shift control means (CPU). (4) and a driver 5 for driving the drive of the VFS V / V.

The operation of the conventional variable force solenoid drive device having the configuration as described above is as follows.

When a triangular waveform is output by the resistor R6 and the capacitor C4 in the pulse generator 1 and applied to the inverter Inv according to the supply of power, the inverter Inv converts the triangular waveform into a square wave. To the current amplifier 2.

When the current amplifier 2 amplifies the driving current applied to the current required for the operation of the regulator 4, a current of approximately 50 mA, and applies the voltage to the voltage generator 3, the voltage booster 3 is a current amplifier. The current applied from (2) is added to the power (VIG) applied through the diode (D4) to be output as approximately twice the power (VIG) at the output terminal of the diode (D3) to supply to the regulator (4) as drive power. do.

When the PWM duty signal for driving VFS V / V is applied from the shift control means (CPU) while the regulator 4 is driven by the supply of the driving power as described above, the regulator 4 causes the resistor R3 and the capacitor C2 to be applied. The control signal for driving VFS V / V is output at the output frequency set to.

Accordingly, the driving unit 5 drives the applied VFS V / V driving signal to drive the VFS V / V, and the sensing resistor R1 senses the output current of the driving unit 5 and then the regulator 4. In response to this, the output current for driving VFS V / V is adjusted to stabilize.

In the conventional automatic transmission as described above, the VFS driving device requires a complicated circuit such as a waveform generation circuit, a current amplification circuit, and a voltage divider circuit for driving the regulator, resulting in a rise in manufacturing cost and complexity of control. have.

In addition, since both the power supply and the IG power are used at the same time, it is cumbersome to use two power sources, and if any one power supply is stopped, a problem occurs that the entire function of the circuit is stopped.

In addition, since the detection of the feedback current using the sensing resistor detects only information on the operation and non-operation of the VFS V / V, precise self-diagnosis is not performed.

The present invention has been invented to solve the above problems, the object of which is to provide high-side control using a single power supply in the feedback control of the VFS to provide simplicity of control and stability of the circuit, and to provide samples and hold The feedback detection of the amount of control current used provides precise self-diagnosis of the VFS and stability of control.

According to an aspect of the present invention, there is provided a VFS V / V driving apparatus of an automatic transmission, comprising: a driving signal processing unit for driving a drive of a VFS V / V by processing a PWM duty signal output from a shift control apparatus; A current detector which detects a driving current of the VFS V / V and applies it as a feedback signal to the shift controller; And a sample / hold unit configured to sample / hold the detection current supplied as a feedback signal to the shift control device and output the analog current signal.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As can be seen in FIG. 1, the variable force solenoid driving device according to the present invention includes a drive signal processor 10, a current detector 20, and a sample / hold unit 30.

The driving signal processor 10 drives the driving of the VFS V / V by processing a signal, a PWM duty signal (0 to 100%) of approximately 600 Hz, for driving the VFS output from the shift control apparatus.

The driving signal processor 10 may include a first inverter U6B for inverting the phase of the PWM duty signal output from the shift control device and a second inverter for reversing the signal inverted in the first inverter U6B to the original phase. 2 inverter U6C, a transistor Q3 output from the second inverter U6C and switched on / off according to a signal applied to a base terminal, and interlocked switching according to on / off switching of the transistor Q3. And an N-channel FET Q4 for driving VFS V / V at a voltage of IG-1.

One end of the current detector 20 is connected to the drain terminal of the N-channel FET Q4 to detect the driving current of the VFS V / V from the voltage difference between both ends, and the N-channel FET supplied through the resistor R26 ( Q4) a comparator U7A for comparing and outputting the VFS V / V driving current at the drain stage and the negative power supplied through the diode D9 and the resistor R33.

The sample / hold unit 30 is composed of a differential circuit including a transistor Q5, a resistor R28, and a capacitor C19, and is switched according to a signal output from the first inverter U6B of the driving signal processing unit 10. In this way, the feedback current for the VFS V / V drive is sampled and held and applied to the shift controller.

In the present invention having the above configuration, an operation of controlling the driving of the VFS V / V using the high side single power supply will be described below.

According to various vehicle status information detected during driving and driving intention of the driver, the driving signal processor may output a constant frequency signal of a variable duty for controlling the driving of the VFS V / V as shown in FIG. The transistor Q3 is applied to the base terminal of the transistor Q3 through the inversion and reversal of the phase by the first and second inverters U1 and U2 in (10).

Accordingly, the N-channel FET Q4 is switched and the power supply VIG connected to the diode terminal via the diode D7 is output through the drain terminal, and the driving current is supplied to the VFS V / V side through the sensing resistor RS34. Is supplied.

As described above, the driving current supplied to the VFS V / V is detected by the sensing resistor RS34 in the current detector 20, and the current between the both ends of the sensing resistor RS34 is represented in the form of voltage so that the resistor R26 and the resistor ( R33) is input to both terminals of the comparator U7A.

At this time, the voltage Va at the point 'A' detected by the sensing resistor RS34 is multiplied by the relationship of VIG-VD7 and detected as shown in (b) of FIG. 2, and the voltage Vb at the point 'B'. Is detected as shown in Fig. 2 (c) attached by the relation of "resistance value of VFS V / V x Va ÷ (resistance value of VFS V / V + resistance value of RS34)".

The comparator U7A compares the voltage between the both ends of the input sensing resistor RS34 and inputs a result as shown in FIG. 2D to the emitter terminal of the transistor Q5 in the sample / hold part 30. Applied by signal.

At this time, the input voltage (V +, V-) of both ends of the comparator (U7A) is equal to the voltage difference between both ends of the sensing resistor (RS34), the voltage input between the both ends is "R26 × Va ÷ (R26 + R27)" value Is formed.

Therefore, when the output voltage Vo of the comparator U7A is obtained, (Vb-V +) ÷ R33 = (V +-Vo) ÷ R33.

Therefore, if R32 / R26 is 'C', Vo = A (Va-Vb).

That is, the comparator U7A amplifies and outputs the ratio of R26 and R32 with respect to the voltage between the input terminals.

At this time, the input voltage between the both ends of the comparator U7A cannot exceed the range of the supplied power voltage (VIG ~ 0V), and the output voltage Vo may not exceed the range of the power voltage (VIG ~ 0V).

As described above, when the voltage between both ends of the sensing resistor RS34 output from the comparator U7A is output and input to the emitter terminal of the transistor Q5 in the sample / hold unit 30, the variable duty signal output from the shift controller is output. Since the phase is reversed when passing through the first inverter U6B, the transistor Q5 is turned on by the phase inverted signal at the falling edge of the variable duty signal, so that the voltage output through the collector terminal is a resistor ( The capacitor C19 is charged through R28.

In addition, a signal in which the phase inverted by the first inverter U6B at the rising edge of the variable duty signal output as shown in FIG. 2A attached by the shift control means is applied to the base terminal of the transistor Q5. Since it is applied, the transistor Q3 is turned off.

Therefore, the voltage charged in the capacitor C19 is discharged and applied as a feedback signal to the shift control apparatus side with an analog voltage as shown in FIG.

Therefore, the shift control apparatus analyzes the detected feedback signal and corrects and controls the variable duty by driving the VFS V / V.

That is, when the variable duty ratio is high, the analog voltage detected by the feedback is high, and when the variable duty ratio is decreased, the analog voltage detected by the feedback is also decreased.

In addition, the shift control apparatus compares an analog signal such as (e) of FIG. 2 detected as a feedback signal with a variable duty for driving the VFS V / V. If it is judged as a fault and outputs the self-diagnosis code, and if the self-diagnosis code for the fault is outputted and accumulated as a result of the self-diagnosis, the output of the variable duty for driving VFS V / V is stopped to hold the shift stage for 3 speed Perform lymphatic home mode.

As described above, the present invention provides high-side control using a single power supply to provide feedback control of the VFS and provides stability of the circuit and stability of the circuit. The VFS V / V self-diagnosis and control stability are provided.

1 is a configuration diagram for a variable force solenoid driving device in an automatic transmission according to the present invention.

2 is a timing diagram for a variable force solenoid drive in an automatic transmission according to the present invention.

Figure 3 is a configuration diagram for a variable force solenoid drive device in a conventional automatic transmission.

Claims (4)

In the VFS V / V drive of the automatic transmission, A driving signal processing unit processing a PWM duty signal output from the shift control device to drive the driving of the VFS V / V; A current detector which detects a driving current of the VFS V / V and applies it as a feedback signal to the shift controller; And a sample / hold unit which samples / holds a detection current supplied as a feedback signal to the shift control device and outputs the analog current signal as a sample / hold unit. The method of claim 1, The drive signal processor includes: a first inverter for inverting the phase of the variable duty signal output from the shift control apparatus; A second inverter which inverts the signal inverted in the first inverter to its original phase; A transistor output from the second inverter and switched on / off according to a signal applied to a base terminal; And an N-channel FET which is cooperatively switched according to on / off switching of the transistor to drive VFS V / V at a voltage of IG-1. The method of claim 1, The current detector includes: a sensing resistor for detecting a voltage difference between both ends according to VFS V / V driving; And a comparator for comparing and amplifying and outputting a voltage difference between the both ends of the sensing resistor. The method of claim 1, The sample / hold section 30 includes a transistor switched according to a signal output from the first inverter in the driving signal processing section; And a capacitor configured to sample / hold a feedback current for VFS V / V driving according to the switching of the transistor.