WO2004044529A1

WO2004044529A1 - Noncontact controller of electronic accelerator for an internal-combustion engine and an electric vehicle

Info

Publication number: WO2004044529A1
Application number: PCT/KR2003/000076
Authority: WO
Inventors: Hyo-Moon Lee
Original assignee: Control & Measurement Systems Co., Ltd.
Priority date: 2002-11-12
Filing date: 2003-01-14
Publication date: 2004-05-27
Also published as: KR100458374B1; AU2003202165A1; KR20040041825A

Abstract

A non-contact electronic controller for the control of acceleration is disclosed. The non-contact electronic controller can be used for an internal-combustion engine and an electric vehicle and can reduce dirty smoke emission and waste of fuel by controlling exactly the amount of fuel applied to an engine. By having a compression spring together with a tension spring, the non-contact electronic controller can keep a stable output value and can achieve a long life. Moreover, the non-contact controller can perform functions such as elimination of power source noise, output compensation, and compensation for electrical hysteresis by having a compensating circuit. Also, the non-contact controller can solve problems such as durability of a magnetic material, limit of the range of output voltage, and the need to have a temperature compensation circuit by using a permanent magnet with stabilized magnetic line of force.

Description

NONCONTACT CONTROLLER OF ELECTRONIC ACCELERATOR FOR AN INTERNAL-COMBUSTION ENGINE AND ELECTRIC

VEHICLE

Technical Field

The present invention relates to a non-contact electronic controller for the control of vehicle acceleration by control of an electronic fuel feed system of an internal-combustion engine (or the power to a drive motor of an electric vehicle) which reduces dirty smoke emission and waste of fuel by controlling exactly the amount of fuel applied to the combustion chamber of an internal combustion engine by sending electrical signals to an electronic control unit (hereinafter referred to as "ECU") attached to an internal-combustion engine. Moreover, the non-contact electronic controller of the present invention is able to control the motive power in accordance with the driver's intent through the typical user input devices such as foot pedals by means of said electrical signals.

Background Art

Typically special motor vehicles such as fire engines, tow trucks, truck mixers, and aerial lifts have a power take-off (hereinafter referred to as "PTO"), which is a separate output axle extended from a driving axle in order to operate equipment and various apparatus mounted on the vehicles. In addition, these types of vehicles are often designed to transmit power from the vehicle engine to the onboard machines (such as concrete mixers, cranes of wrecker vehicle, and hydraulic pumps) through the PTO while the vehicle's engine runs at idle speed. Unfortunately when the engine of vehicle is running at idle speed, and additional power is required the accelerator pedal in the foot-well cannot be used to adjust the output of the PTO. Therefore, an additional user input devices are essential. These consist of steering levers or choke switches which control the fuel system actuator through mechanical linkages or pneumatic control valves.

For example, in case of a tow truck, a steering lever on a rear turntable or a foot pedal equipped with a pneumatic control valve operates the truck mounted crane. The foot pedal is connected to a push-pull wire or a pneumatic pipe, which operates the fuel control lever of a fuel injection pump thereby controlling the amount of fuel injected to the combustion chamber of the vehicle internal combustion engine. In case of an electric vehicle the driver operate a mechanical lever and the movement is converted into electrical signals by means of a contact resistance potentiometer and the signals are transferred to the ECU of an engine fuel system.

Fig.4a shows a schematic diagram of a conventional acceleration control system. The system cannot provide electrical signals, which are essential for an electronic engine control device demanded by the new regulations for clean air and conservation of the environment. In addition, the performance of mechanical push-pull cables can deteriorate over time and pivot pins of steering levers wear and result in poor erratic control. In addition, it is often necessary to allow physical space between the position of an accelerator device and an engine and mechanical cables of more than 10 meters in length are not uncommon.

In order to solve these problems and difficulties, an electronic controller of acceleration, in particular a non-contact controller using a Hall element has been developed. The non-contact controller is positioned near a conventional mechanical choke or a steering lever and changes mechanical movement of the devices into electrical signals, thereby transferring acceleration intent of a driver to ECU of an engine. Examples of such controllers are disclosed in Korean Patent Publication Nos. 2002-0038948, 2002-0000765, 2002-0036376, 2001-0001844, 2000-0074071 and 2000-0070640, and Korean Patent No. 229626. However, these existing non-contact controllers have several problems.

With a movable member that includes a magnetic element, the restoring force of the movable member deteriorates with time and often has poor endurance, and as a result, the initial output value can drift. In addition, additional problem is that the compensating circuit for output signals of a Hall element is incomplete and, therefore, it is difficult to perform various functions such as elimination of power source noise, output compensation, compensation for electrical hysteresis, and converting into various output waveforms. Consequently, the range of output voltage is limited due to flux leakage of magnetic materials, and a temperature compensation circuit for magnets and electronic components is essential. Disclosure of Invention

Accordingly, the present invention is directed to a non-contact electronic controller for the control of acceleration that substantially obviates one or more problems due to limitations and disadvantages of the related art. An object of the present invention is to provide a non-contact electronic controller for the control of acceleration, which is disposed near a mechanical choke or a steering lever device and can correctly transfer acceleration intent of a driver to an electronic control unit of an engine by converting mechanical movement into electrical signals. Another object of the present invention is to provide a non-contact electronic controller for the control of acceleration, which enhances the restoring force and safety of a movable member by mounting two springs, that performs various functions, such as elimination of power source noise, output compensation, compensation for electrical hysteresis, and convert the signal into various output waveforms, by installing a compensation circuit for output signals of a Hall element, and enhancing the output range by mounting a permanent magnet which has excellent temperature characteristic and stable magnetic line of force.

Additional advantages, objects, and features of the present invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained the written description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, there is provided a non-contact electronic controller for the control of acceleration for an internal-combustion engine and an electric vehicle, comprising: a movable member equipped with a permanent magnet with excellent temperature characteristic; a compression spring and a tension spring to enhance restoring force of the movable member; a Hall element to sense the change in magnetic flux density of the permanent magnet; and an electric circuit board to perform various functions, such as output compensation, compensation for electrical hysteresis and conversion of the output signals of the Hall element to various output waveforms.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

Brief Description of the Drawings

The accompanying drawings, which are included, to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention. In the drawings:

Fig.l is an exploded perspective view of a non-contact electronic controller for the control of acceleration for an internal-combustion engine and an electric vehicle in accordance with the present invention;

Fig.2 is a perspective view of internal components of a non-contact electronic controller for the control of accelerator for an internal-combustion engine and an electric vehicle in accordance with the present invention; Fig.3 is a plane view of internal components of a non-contact electronic controller for the control of accelerator for an internal-combustion engine and an electric vehicle in accordance with the present invention;

Fig.4a is a schematic diagram showing a conventional acceleration control system; Fig.4b is a schematic diagram showing the acceleration control system in accordance with the present invention; and

Fig.5 is a block diagram of an electric circuit board mounted on a non- contact electronic controller for the control of acceleration for an internal- combustion engine and an electric vehicle in accordance with the present invention. Best mode for Carrying Out the Invention

Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Fig.4b is a schematic diagram showing the acceleration control system in accordance with the present invention. Anon-contact electronic controller 100 for the control of acceleration is positioned between an accelerator 60 or a cable steering lever 61 and an ECU 210 of an engine fuel system 200 in environment- friendly electronic control engine 300, and controls the amount of fuel applied to the combustion chamber of an internal-combustion engine or the rotation speed of an electric motor.

In further detail, as best shown in Figs.1-3, a non-contact electronic controller for the control of acceleration according to the present invention has a wire 14 which is installed on one side of a housing 10, and an electric cable 12 on the opposite side of the housing 10. The wire 14 is linked to a device for accelerating, for example, the conventional accelerator 60 or the steering lever 61 in Fig.4b, and the electric cable 12 to the ECU 210. The top of the housing 10 is covered with a cover 50 using an adhesive such as epoxy resin, thereby sealing the unit. A "c"-shaped rectangular frame 16 including a space area 17 is positioned inside the housing 10, and a Hall element 18 is disposed at the end of one side of the rectangular frame 16. And a movable member 20, which moves linearly along the space area 17, is disposed in the space area 17. A permanent magnet 24 is inserted and fixed in one side of the movable member 20. The permanent magnet 24 is disposed facing the Hall element 18 and movably relative to the Hall element 18. There is a fixing bar 28 on the front side of the movable member 20. One end of a compression spring 36 to assist a tension spring 48 is fastened to the fixing bar 28, and the other end is fixed to the housing 10 through the front side of the rectangular frame 16. Here, the tension spring 48 causes the movable member 20 to be always positioned in the rearward of the rectangular frame 16 so that a non-contact electronic controller can always keep an initial output value. If the tension spring 48 is broken or worn-out, the said compression spring 36 can be utilized instead of the tension spring 48. The movable member 20 is in contact with a switch 54, which is disposed on the rearward of the movable member 20 in the housing 10. The movable member 20 and the switch 54 always remains connected but changes into the disconnected state as soon as the movable member 20 travels along the space area 17.

The rectangular frame 16 is covered with an inner cover 30, which has an oblong guide-hall 32 in the center and an axis bar 34 on the top. A projection bar 26, which is formed on the top of the movable member 20, is inserted into the guide-hall 32. The axis bar 34 is inserted into a hole 42 formed in the center of a lever 40, and, therefore, the lever 40 is pivoted with respect to the axis bar 34. Here, the lever 40 tends to come back to the original position because of the tension spring 48, one end of which is fixed to a lug 40a of the lever 40 and the other end to a spring fixing bar 19 in the housing 10. On the other hand, the wire 14 is fixed to a connection point 46 on the lever 40 through the housing 10, and the said projection bar 26 is inserted into an elliptic hole 44, which is formed on the lever 40, through the guide-hall 32. Particularly, in the upper part of the lever 40, the lower segment from the contact surface on which the lever 40 comes in contact with the wire 14, may be an oval shape based on angle, contact surface area, size, and the like so as to protect the wire 14 from deformations such as folding, separation, and abrasion. In addition, an electric circuit board 52, which is installed at the inside of the housing 10, is connected to the ECU 210 by means of the cable 12. The circuit board is also connected with the switch 54 and the Hall element 18.

Thus, if an operator steps on the accelerator 60 or pulls the steering lever 61 in order to get an power machine to work, as shown in Fig.3, the wire 14 is strained and the lever 40 moves rearward. At the same time, the movable member 20 travels rearward along the guide-hall 32 and is separated from the switch 54. Here, the release signal of the switch 54 is sent to an electric circuit board 52. The movable member 20 carries the permanent magnet 24 that moves relative to the Hall element 18, and, therefore, the change of flux density formed between the Hall element 18 and the permanent magnet 24 causes the current of Hall element to change accordingly. The change of current is converted into appropriate signals that are required in the ECU 210 of the engine fuel system 200, and is transferred to the ECU 210. The ECU 210 calculates the optimal amount of fuel required according to the present state of the engine and actuates a fuel pump 230 using an actuator 220, thereby controlling the amount of fuel applied to the combustion chamber of an internal combustion engine. The said permanent magnet 24 is made of AlNiCo with excellent temperature characteristic, which keeps stabilized magnetic line of force by saturating and demagnetizing up to about 70%.

If an operator stops the operation of the accelerator or the steering lever, the wire is loosened and the lever 40 comes back to the original position because of the restoring force of the tension spring 48. The return of lever 40 causes the movable member 20 to come back to an original position, and, therefore, the permanent magnet 24 that is mounted on the movable member 20 moves relative to the Hall element 18. Subsequently, the Hall element 18 provides signals indicative of the position of the permanent magnet 24 to the ECU 210. Also, the movable member 20 is brought into contact with the switch 54 and the switching signal is perceived as an idle validation switch to an internal combustion engine or a safety switch to the motor of an electric vehicle.

In addition, even though the tension spring 48 is broken, the movable member 20 comes back to the original position due to the resilience of the compression spring 36. In other words, the acceleration controller has a double safety spring structure.

In the non-contact electronic controller of the present invention, all the parts in the housing 10 and the cover 50 are made of engineering plastics, thereby being able to be protected from electromagnetic interference, which is attributed to the electrical devices such as an electric circuit board and a Hall element. Particularly, each contact surface of the housing 10 and the cover 50 has a convexo-concave structure, and the contact surface of the housing 10 is closely coupled to that of the cover 50 using an adhesive such as epoxy resin rather than a mechanical fastening means such as bolts. Therefore, the degree of industrial protection for the inside of the housing 50 secures more than protection class IP65. Fig.5 is a block diagram of an electric circuit mounted on the non-contact electronic controller for an internal-combustion engine and an electric vehicle in accordance with the present invention. The electric circuit performs various functions such as elimination of power source noise, output compensation, compensation for electrical hysteresis, and converting into various output waveforms. Here, the power can be obtained from the battery of a vehicle and is adjusted by a regulator block 101. There are two types of the voltage range, i.e., 24-48N and 60-96 V, each of which is selected according to the rated voltage of an electric vehicle. The power stabilized through the regulator block 101 is used as input power for a Hall element block 102, a signal processing block 103 and a gain adjustment block 105. The Hall element block 102 provides voltage output signals in the range of 0-5V, which changes proportionately according to the quantity of change of magnetic flux. The signal processing block 103 can convert the voltage-variable signal from the Hall element block 102 into various signal forms required at the ECU 210, such as PWM(Pulse Width Modulation), frequency variable signal, forward/backward signal, and flat signal switch, and it is possible to add as many as three switch functions. A filter block 104 for elimination of signal noise can effectively get rid of the noise which is generated during signal processing or included in input power, and perform a protection function for a circuit including forward/backward impression and a short circuit. A gain adjustment block 105 effectively limits the minimum and maximum value of a final output signal from the filter block 104, thereby adjusting adequately the minimum and maximum rpm of an engine at idle according to the required design criterion for a power machine in order to control effectively a power machine.

Industrial applicability

Thus, a non-contact electronic controller for an internal- combustion engine and an electric vehicle can convert a physical quantity of change in a mechanical accelerator or cable lever device into electrical signals using a permanent magnet disposed movably relative to a Hall element. Therefore, the non-contact electronic controller can use the electrical signals as input signals to control the speed of an environment-friendly electronic internal-combustion engine or a drive motor of an electric vehicle, thereby controlling an engine electrically without alteration of existing devices and keeping more durable quality than the conventional contact resistance method. In addition, the non-contact electronic controller provides signals with resolution of more than 800 samples to ECU using an electric circuit, and the ECU can control correctly and finely an engine or a drive motor, thereby being able to operate a power machine smoothly and reduce unnecessary consumption of energy.

Particularly, by having a compression spring together with a tension spring and enhancing restoring force of a movable member, the non-contact electronic controller can keep output at an initial value although it is used for a long time. Moreover, by having an electric circuit board with a compensating circuit, it is possible to perform functions such as elimination of power source noise, output compensation, compensation for electrical hysteresis, and converting into various output waveforms. Also, by using a permanent magnet with stabilized magnetic line of force, the non-contact controller is able to solve conventional problems such as durability of a magnetic substance, limit of the range of output voltage due .to the change of magnetic force according to the change of circumstances, and the need to have a temperature compensation circuit for a magnet and electronic components.

Claims

What Is Claimed Is:

1. A non-contact electronic controller for the control of acceleration for an internal-combustion engine and an electric vehicle using a Hall element and a permanent magnet, the non-contact electronic controller comprise a housing connected with a wire on one side thereof and a cable on the opposite side; a movable member equipped with a permanent magnet, the permanent magnet being fully saturated and then demagnetized so as to achieve a stable magnetic strength; a double return spring mechanism being composed of a compression spring and a tension spring to restore the movable member to an original position; a "<z"-shaped rectangular frame including a space area so that the movable member travels linearly along the space area, the rectangular frame being equipped with a Hall element, the Hall element sensing the change of magnetic flux density according to the movement of the permanent magnet disposed movably relative to the Hall element; an inner cover covering the top of the rectangular frame, the inner cover bearing an oblong guide-hall in the center thereof, the oblong guide-hall into which a projection bar positioned on the movable member is inserted; and an electric circuit board compensating and adjusting output signals from the

Hall element, the electronic circuit board transferring the compensated and adjusted signals to ECU.

2. The non-contact electronic controller of claim 1, wherein the mechanical wire is connected with a pedal and the electrical cable is connected with the ECU.

3. The non-contact electronic controller of accelerator of claim 1, wherein the permanent magnet is made of AlNiCo demagnetized up to 70% after full saturation in order to stabilize magnetic force.

4. The non-contact electronic controller of accelerator of claim 1, wherein the compression spring performs ancillary functions for the tension spring and is disposed between the front side of the movable member and the housing.

5. The non-contact electronic controller of accelerator of claim 1, wherein the rectangular frame is coupled to the inner cover comprising: an axis bar being used as the center of rotation of a lever; and the guide-hall being used for the movement of the movable member.

6. The non-contact electronic controller of accelerator of claim 1, wherein the lever is disposed on the top of the inner cover so that the movable member can travel by means of rotation of the lever, the lever comprising: a hole into which the axis bar is inserted; an elliptic hole into which the projection bar is inserted; a wire connection point to which the wire is fixed; and a lug to which one end of the tension spring is fixed.

7. The non-contact electronic controller of accelerator of claim 1, wherein the housing includes a mechanical micro-switch to transfer on-off signals to the electric circuit board according to whether the moveable member is contacted with the switch.

8. The non-contact electronic controller of accelerator of claim 1, wherein the electric circuit board receives the signals from the Hall element and the switch and then manipulates the input signals into the signal forms required by the ECU and transfers the manipulated signals to the ECU.