EP3169546A1

EP3169546A1 - Haptic accelerator pedal having a control-unit assembly

Info

Publication number: EP3169546A1
Application number: EP15723963.3A
Authority: EP
Inventors: Thomas Lang; Burkhard Schneider
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2014-07-17
Filing date: 2015-05-21
Publication date: 2017-05-24
Also published as: WO2016008624A1; JP2017522220A; KR20170035896A; DE102014213975B3

Abstract

The invention relates to a haptic accelerator pedal (3) having a control-unit assembly for a motor vehicle. The accelerator pedal comprises a pedal lever (7), an actuator (9) that can be coupled to the pedal lever (7), a position sensor (19), and an accelerator pedal control unit (5). The pedal lever (7) can be moved along a travel path (13). The actuator (9) is designed to apply a force to the pedal lever (7) in a controllable manner. The position sensor (19) is designed to sense a position of the pedal lever (7) along the travel path (13) and thereupon to output a position signal. The accelerator pedal control unit (5) is designed to control the actuator (9) in such a way that a predetermined force is applied to the pedal lever (7). The accelerator pedal (3) is distinguished in that the accelerator pedal control unit (5) taps the position signal of the position sensor (19) but is galvanically isolated from the position sensor (19). For example, the position signal can be tapped by means of an isolation amplifier (27). Because of the galvanic isolation between the position sensor (19) and the accelerator pedal control unit (5), electrical influences with an engine control unit (29) that is directly electrically connected to the position sensor (19) can be avoided.

Description

description

Haptic accelerator pedal with control unit arrangement Field of the invention

The invention relates to a haptic accelerator pedal with a control device arrangement for driving a coupled with a pedal lever actuator of the haptic accelerator pedal.

Background of the invention

In many modern motor vehicles, the accelerator pedal, which is also commonly referred to as an accelerator pedal, no longer acts mechanically directly via a linkage or the like, e.g. on throttle elements of a vehicle engine or on an injection system of the vehicle engine. Instead, a current position of a pedal lever of the accelerator pedal, which is actuated by a driver, detected via one or more sensors and transmit the associated information to an engine control unit. In order to detect the position of the pedal lever, e.g. simple potentiometers or Hall sensors are used.

DE 699 29 344 T2 describes a method for operating a

Control device by means of which an engine of a vehicle can be controlled in response to an operation of a pedal.

In haptic accelerator pedals, which are sometimes referred to as active accelerator pedals, the pedal lever can be acted upon by an actuator targeted with a force. In this way, signals can be transmitted haptically to the driver and thereby be given feedback on vehicle states or driving situations, for example. For example, a virtual pressure point on the pedal lever can be generated, which should signal to a driver that, for example, fuel consumption will increase sharply as the pedal lever further depresses. Also, for example, by a deliberately caused pulsation or vibration of the Pedal levers hazardous situations or driving situations in which fuel can be saved with appropriate behavior, are signaled.

In order to be able to control or regulate the actuator of a haptic accelerator pedal in an appropriate manner, an accelerator pedal control device generally requires information about the current position of the pedal lever and possibly also information about a current positioning of the actuator.

Conventionally, in addition to a position sensor, which detects the current position of the pedal lever to a corresponding signal to a

Pass on engine control unit, a further position sensor may be provided, which detects the current position of the pedal lever to them the

Forward accelerator control unit. The additional position sensor increases both the cost and the installation space of the entire system.

Alternatively, the relayed from the position sensor to the engine control unit position signal by an additional interface on

Engine control unit are tapped and forwarded to the accelerator pedal control unit. However, an additional wiring effort including suitable interfaces is necessary for this purpose, and a transmission of the position signal can sometimes take place only with considerable time delay.

Disclosure of the invention

Embodiments of the present invention can advantageously make it possible to provide an accelerator pedal control unit with a signal that represents a current position of a pedal lever of the accelerator pedal in a cost-effective and low-cost manner with respect to components and installation space.

According to a first aspect of the invention, a haptic accelerator pedal is proposed with a control device arrangement which has a pedal lever, an actuator which can be coupled to the pedal lever, a position sensor and an accelerator pedal control device. The pedal lever is displaceable along a travel path. The actuator is adapted to exert a force controllably on the pedal lever. The position sensor is configured to detect a position of the pedal lever along the travel path and then output a position signal. The accelerator control unit is designed to the Actuator to control such that a predetermined force is exerted on the pedal lever. The haptic accelerator pedal is characterized in that the accelerator control unit picks up the position signal of the position sensor, wherein the accelerator control unit is electrically isolated from the position sensor.

Ideas for embodiments of the present invention may be considered, inter alia, as being based on the thoughts and findings described below.

As indicated in the introduction, in conventional haptic accelerator pedals, a position signal which indicates the current position of the pedal lever and which is to be forwarded to an accelerator pedal control unit, either detected by means of an additional position sensor and the

Accelerator pedal control unit transmitted, or it is only a single position sensor provided, the position signal is first forwarded to an engine control unit and is then transmitted from there via a complementary interface and additional wiring to the accelerator pedal control unit. Both variants require additional structural complexity. In addition, in the second variant, time delays may occur in the transmission of the position signal.

One idea is now to pass on the position signal, which is preferably detected by a single position sensor, to an engine control unit and to additionally pick it up in order to additionally direct it to the accelerator pedal control unit.

It was recognized that it had to be considered that the

Engine control unit and the accelerator control unit in general

subject to different boundary conditions. In particular, the two control units can be at different electrical potentials. To the

For example, the engine control unit is usually hardly loaded so that it is usually substantially at the potential of the battery of the vehicle. The accelerator control unit, however, usually has to control the actuator of the accelerator pedal and thereby deliver significant benefits, so that the potential at the accelerator pedal control regularly a considerable

Voltage drop is subject. It has been recognized that these different boundary conditions can be accommodated by the fact that the accelerator pedal control unit with the position sensor is not in direct or indirect electrical contact, but is formed by this galvanically isolated.

Galvanic isolation, sometimes also referred to as galvanic decoupling, generally refers to electrical separation of two conductive objects, for example two circuits. It may be advantageous, for example, in metrological applications and in data transmission. In the case of circuits, carriers are unable to flow from one circuit to another, as there is no electrically conductive connection between these two circuits. About corresponding coupling members, however, between the

Circuits electrical power or signals are transmitted. Since electrical potentials are separated from each other in isolated connections, potential-free connections are also used.

Due to the fact that the accelerator pedal control unit the position signal of the

Although picking up position sensor, but is galvanically isolated from the position sensor, it can be prevented that, for example. the electrical control unit directly electrically connected to the position sensor and the electrically isolated accelerator pedal control device influence each other electrically. In addition, an expense for interfaces and cabling can be minimized in a galvanically isolated tapping or coupling of signals.

According to one embodiment, the controller picks up the position signal from the position sensor via a buffer amplifier. Isolation amplifiers, sometimes referred to as isolation amplifiers, can be used to isolate minor voltage or current fluctuations that are modulated, for example, on a voltage applied circuit. For this purpose, a galvanic separation of the biased line circuits of the amplifier circuits prevail. This separation can be done in the simplest case via a double coil using an inductive principle. This is also referred to as transformer coupling. Alternatively, the separation can take place via a capacitor, which is also referred to as capacitive coupling. Only the voltage changes or current fluctuations are transmitted, not the basic voltage. While using the isolation amplifier thus position signals of the

Position sensors can be tapped due to the associated voltage changes, the circuit of the position sensor on the one hand and the circuit of the accelerator control unit on the other hand, decoupled from each other, i. galvanically isolated, remain.

According to one embodiment, it is possible that the accelerator pedal has only a single position sensor for detecting the position of the pedal lever. The position signal of this single position sensor can be made available both to a directly electrically connected engine control unit and to an accelerator control unit connected in an electrically isolated manner.

Optionally, the accelerator pedal may be physically equipped with two identically acting position sensors in order to be able to provide redundancy, for example in the event of a position sensor failure, but the two position sensors are interconnected with exactly the same effect and behave as a single position sensor during normal operation of the accelerator pedal.

According to an embodiment, the accelerator pedal further comprises a position sensor for detecting a position of the actuator. This position sensor may be provided in the accelerator pedal as a separate component. In other words, this position sensor may be provided independently of the position sensor used to detect the position of the pedal lever. It can be directly electrically connected to the accelerator pedal control unit. Signals this

Position sensors may indicate to the accelerator control unit which position the actuator is currently located in and thus may be used for control of the actuator.

According to one embodiment, a control arrangement for a vehicle is also proposed, which has a haptic accelerator pedal according to one of the embodiments described herein as well as an engine control unit. The engine control unit is galvanically connected to the position sensor of the pedal lever. The accelerator pedal control unit can advantageously be galvanically isolated from the engine control unit since the signals of the

Position sensor tapped galvanically isolated and to the

Accelerator pedal control unit be given. The accelerator pedal control unit and the engine control unit may be provided as separate units. alternative Both controllers can also be integrated in a common unit.

It should be understood that some of the possible features and advantages of the invention are described herein with reference to different embodiments. A person skilled in the art will recognize that the features can be suitably combined, adapted or replaced in order to arrive at further embodiments of the invention.

Brief description of the drawings

Embodiments of the invention will now be described with reference to the accompanying drawings, wherein neither the drawings nor the description are to be construed as limiting the invention.

Fig. 1 shows a control arrangement according to the invention for a vehicle, which has a haptic accelerator pedal with an accelerator pedal control unit and an engine control unit.

The figure is merely schematic and not to scale.

Embodiments of the invention

Fig. 1 shows a control arrangement 1 for a vehicle. The

Control arrangement 1 comprises a haptic accelerator pedal 3 with a

Accelerator pedal control unit 5, a pedal lever 7 and an actuator 9.

The pedal lever 7 can be depressed by a driver 11 and thereby displaced along a travel path 13. In the example shown thereby changes its angle ß. The pedal lever 7 is mechanically biased by a spring 15 toward an initial position. The current angle of attack ß of the pedal lever 7 is transmitted to a sensor 17 of a position sensor 19. A position of the encoder 17 or a value indicated by this is determined by detection means 21 of the position sensor 19 and based on this generates a position signal. For redundancy reasons, two detection means 21 are provided. The position signal is then sent to the Motor control unit 29 passed, which is electrically connected via lines 31 to the position sensor 19.

The provided in the haptic accelerator pedal 3 actuator 9 is provided to exert a force controllable on the pedal lever 7. For this purpose, the actuator 9 is driven by a motor 23. The motor 23 is of the

Accelerator pedal control unit 5 controlled or regulated.

In the example shown, a further position sensor 25 is provided which can measure a positioning of the motor 23, in particular a current angular position of the same. This position sensor 25 is electrically connected to the accelerator pedal control unit 5.

In order to be able to control or regulate the motor 23 appropriately, the accelerator control unit 5 generally requires both information about the current one

Position of the pedal lever 7 as well as information about the current

Positioning of the actuator 9. The information about the current positioning of the actuator 9 can be obtained from the position sensor 25. However, the information about the current positioning of the pedal lever 7 should not be directly electrically connected from the position sensor 19, since it is electrically coupled to the engine control unit 29 and a direct electrical

Connection of the position sensor 19 to the accelerator pedal control unit 5 to unwanted electrical influences between these two

Control units 5, 29 could lead.

Therefore, a buffer amplifier 27 is provided, by means of which the

Position signal of the position sensor 19 can be tapped galvanically isolated. The configuration of the isolation amplifier 27 may, depending on

Output signal of the position sensor 21 used in the accelerator pedal, done as a digital or analog separation amplifier. The structure of the isolation amplifier 27 can be made in a discrete structure, with an integrated module or as a solution integrated in the position sensor 21.

Finally, it should be noted that terms such as "inclusive" do not exclude other elements or steps, and terms such as "a" or "an" do not exclude a multitude Steps that have been described with reference to one of the above embodiments may also be used in combination with other features or steps of other embodiments described above.

Reference signs in the claims are not to be considered as limiting.

Claims

claims

1. Haptic accelerator pedal (3) with control unit arrangement, comprising:

a pedal lever (7);

an actuator (9) which can be coupled to the pedal lever (7);

a position sensor (19);

an accelerator control unit (5);

wherein the pedal lever (7) along a travel path (13) is displaceable; wherein the actuator (9) is adapted to exert a force controllably on the pedal lever (7);

wherein the position sensor (19) is adapted to detect a position of the pedal lever (7) along the travel path (13) and then output a position signal;

wherein the accelerator pedal control device (5) is adapted to control the actuator (9) such that a predetermined force is exerted on the pedal lever (7);

characterized in that

the accelerator pedal control unit (5) picks up the position signal of the position sensor (19), wherein the accelerator control unit (5) is galvanically isolated from the position sensor (19).

2. haptic accelerator pedal according to claim 1, wherein the accelerator control unit (5), the position signal from the position sensor (19) via a

Isolation amplifier (27) picks up.

3. Haptic accelerator pedal according to claim 1 or 2, which has a single position sensor (19) for detecting the position of the pedal lever (7).

4. Haptic accelerator pedal according to one of claims 1 to 3, which further comprises a position sensor (25) for detecting a positioning of the actuator (9).

Control arrangement (1) for a vehicle, comprising:

a haptic accelerator pedal (3) according to one of claims 1 to 4;

an engine control unit (29);

wherein the engine control unit (29) is galvanically connected to the position sensor (19).

6. Control arrangement according to claim 5, wherein the accelerator control unit (5) from the engine control unit (29) is electrically isolated.