Brake control device for a motor vehicle

Abstract

TITLE: Braking control device for a motor vehicle Device comprising: a base (1), flat with bearings for an axle (21), a pad (2) mounted on the axle (21) above the base (1), to receive the thrust (F) from the driver's foot, a torsion spring (3) whose body (33) is freely fitted onto the axle (21) and one branch (31) of which is connected to the pad (2) to follow the pivoting movement on the axle, the other branch (32), active, resting by its end (321) on the top of the base (1), a flexible pad (41) held by the top (11) of the base (1) under the bearing end (321) of the active branch (32), a force sensor (4) under the pad (41) receiving the thrust of the active branch (32) via the pad (41),and a processing circuit (5) receiving the signal (S1) from the sensor (4) to process it and supply the processed signal (ST) to the central unit (6) generating the control signal (SC) applied to the braking system. Figure 1,

Description

Title of the invention: Braking control device for a motor vehicle

[0001] 1 FIELD OF THE INVENTION

[0002] The present invention relates to an electrically cable-connected brake control device for the braking system of a motor vehicle. STATE OF THE ART

[0003] Manufacturers are increasingly turning to wired control functions that were traditionally provided by mechanical connections via articulated pedals. However, electric controls make it possible to significantly reduce the size of components and have more space for other elements of the vehicle.

[0004] Various concepts of skates or pedals are already known. Some use force as the sole means of control without mechanical displacement and others use force with displacement to provide better control and allow the use of position sensors in addition to force sensors to improve reliability.

[0005] Some principles are based on articulated pedals of the kinematic type and others on linear movement relative to a guide plane. Both of these solutions have advantages and disadvantages. Pedal-type devices are necessarily bulky, but provide greater comfort for the driver. “Linear” pusher-type devices are more compact, but have the disadvantage of depending on the friction resulting from the offset of the input thrust applied by the driver.

[0006] PURPOSE OF THE INVENTION

[0007] The aim of the present invention is to develop a device for controlling the braking by wire of a vehicle, without mechanical connection between the control device constituted by a pad actuated by the driver and the braking system of the vehicle, reducing the size, the complexity and improving the comfort of the driver, in particular the pedal feel and the braking effect felt as well as the control capabilities and the flexibility.

[0008] DISCLOSURE AND ADVANTAGES OF THE INVENTION

[0009] For this purpose, the invention relates to a braking control device for a motor vehicle comprising: a base, flat with bearings for an axle, a pad mounted on the axle above the base, to receive the thrust of the driver's foot, a torsion spring whose body is freely fitted onto the axle and one branch of which is connected to the pad to follow the pivoting movement on the axle, the other active branch, resting by its end on the top of the base, a flexible pad held by the top of the base under the support end of the active branch, a force sensor under the pad receiving the thrust of the active branch via the pad, and a processing circuit receiving the signal from the sensor to process it and provide the processed signal to the central unit generating the control signal applied to the braking system.

[0010] The device according to the invention has the advantage of limiting the movement of the pad by the spindle rotating around its axis. This avoids the effects of friction linked to the offset of the application of the thrust on the pad thanks to the lever arm of the point of application of the thrust on the pad and its axis of rotation. The movement is smooth without sliding effect as opposed to a linear movement of the push button type. Indeed, linear guidance sensitive to environmental contamination requires appropriate protection in the form of a compressible element or a means for receiving the stroke. Articulated mechanisms, less sensitive, require less protection, which facilitates the insulation and protection of the electronic components, in the lower part of the chassis. In addition, linear compression type systems have a compression spring to meet the required characteristics.Such springs have a large vertical footprint to provide the required thrust and ensure reliability. However, the combination according to the invention of compression springs with an angular displacement of the pad facilitates the integration of the spring function in a more compact, or even very compact, design.

[0011] According to another characteristic, the device comprises a rotation sensor combined with the pad to detect the pivoting movement of the pad relative to the base and provide a signal transmitted to the processing circuit.

[0012] According to another characteristic, the control device comprises a split torsion spring, associated by its respective active branch with a respective flexible plate for each of the force sensors, to provide two detection signals to the processing circuit. Brief description of the drawings

[0013] The present invention will be described below in more detail with the aid of embodiments of a braking control device for a motor vehicle according to the invention shown in the accompanying drawings in which:

[0014] [Fig.l] side view of an example of a control device,

[0015] [Fig.2] schematic top view of the device of [Fig.l],

[0016] [Fig.3] sectional view of a variant of the control device,

[0017] [Fig.4] top view of the device of [Fig.3],

[0018] [Fig.5] sectional view of another embodiment,

[0019] [Fig.6] Top view of the embodiment of [Fig.5].

[0020] 1 DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0021] According to [Fig.l], the invention relates to a braking control device 100 for a motor vehicle. The device 100 consists of a flat and thin base 1, which is placed on the floor of the passenger compartment in the usual position of a brake pedal or in a more appropriate position for this new form of brake pedal. The device 100 is actuated in the usual manner by a push F from the driver's foot.

[0022] The base 1 in the form of a flat box is provided with a top 11, for example, a cover carrying by a bearing 12, the axis 21 of a pad 2 receiving the thrust (F) from the driver's foot. In this example, the bearing 12 is split at the two ends of the axis 21.

[0023] The pad 2 is combined with a torsion spring 3 with two branches 31, 32, the body 33 of which is fitted onto the axis 21. One branch 31 is integral with the pad 2 and the other active branch 32 bears by its end 321 on a flexible element in the form of a plate 41 integrated in the top 11 of the base 1 to receive the end 321 as a support when the pad 2 is subjected to a thrust F.

[0024] The plate 41 is connected directly or via a rigid pusher 42 to a flat force sensor 4, installed in the base 1, on the plate of a printed circuit forming the processing circuit 5. The circuit 5 receives the signal SI from the sensor 4. The active arm 32 shorter than the pad 2 integrating the arm 31 (or integral with it) makes it possible to have a pad 2 of dimensions similar to those of a brake pedal, for reasons of comfort and safety of use; the active branch 32 shorter than the panel 31 is less bulky on the top of the cover 11. The plate 41 constitutes the surface for receiving the thrust exerted by the end 321 of the active arm 32.The thrust thus exerted on the contact zone of the end 321 with the plate 41 is comparable to a thrust perpendicular to the top 11, transmitted by the pusher 42; the latter is only an intermediate element of very low height located on the inner side of the cover 11 and in contact with the top of the sensor 4. The sensor 4 itself is supported through the circuit plate 5 against the bottom 11a in the base 1 without stressing the circuit plate 5. The plate 41 makes the transmission of the thrust independent of the size of the sensor 4.

[0025] Starting from the signal SI received from the force sensor 4, the circuit 5 forms the processed signal ST supplied to the central management unit 6 generating the control signal SC of the braking system (not shown) acting on the wheel brakes and the transmission (dynamic braking).

[0026] The sensitive electronic components of the processing circuit 5, for example, the printed circuit, are protected by the top 11 in the form of a cover ensuring sealing and integrating the plate 41. The electronic components do not require dynamic movement for the detection of the thrust by the force sensor 4. According to a variant, the cover 11 is a simple elastomer membrane or a rigid plate with locally a flexible plate 41, integrated in a sealed manner so as not to influence the transmission of the thrust to the sensor 4.

[0027] The top view ([Fig.2]) shows a variant of the device 100 comprising the torsion spring 3 and its two branches 31, 32 as well as the flexible plate 41 for transmitting the thrust F to the force sensor 4 but which, in addition to the force sensor 4, comprises a rotation sensor 7 for detecting the position of the pad 2. This detection is done without contact by a magnet 71 secured to the axis 21 and cooperating with a magneto-sensitive detection element 72, fixed and giving a signal S2. The axis 21 is integral in rotation with the pad 2.

[0028] The processing circuit 5 receives the signals SI and S2 to form the processed signals STI, ST2 transmitted to the central unit 6. The rotation sensor 7 is, to a certain extent, redundant with the force sensor 4 to check the consistency of the signal SI from the sensor. This check and the consequences, for example, in the event of failure of the sensor 4, allow the control unit 6 to control the braking system.

[0029] Depending on the degree of development of the processing circuit 5, the signals S1, S2 are combined according to data combination rules so that the processing circuit 5 provides a single output signal ST sent to the control unit 6.

[0030] Figures 3 and 4 show another embodiment 300 corresponding to that of [Fig.2] completed by a stroke sensor 8 cooperating with a rod 81 secured to the pad 2 as shown schematically. The signal S3 from the stroke sensor 8 is used in parallel with the signal SI from the force sensor 4 to confirm the validity of this signal. This comparison also makes it possible to detect possible operating incidents.

[0031] According to the braking management mode, a single processed signal ST is transmitted by the processing circuit 5 receiving the two signals SI, S2 and taking them into account according to the rules for their management and taking them into account or transmitting them separately after processing to the control unit 6.

[0032] Figures 5 and 6 show a sectional view and a top view of a device 400 doubling the torsion spring and the force sensor of the first embodiment 100.

[0033] The split torsion spring, associated with the single axis 21, is formed of two springs 3a, b to actuate two force sensors 4a, b by the two active branches 32a, b applying to two plates 4la, b; each transmits the thrust F to a sensor 4a, b located under a respective, distinct plate 4la, b; each sensor 4a, b provides a signal SI, SI' to the processing circuit 5 which provides the processed signal, ST to the unit central unit 6 generating the control signal SC of the braking system. The signals SI, S' 1 of the sensors can also be processed and supplied separately to the central unit 6 which interprets them to generate the control signal SC.

[0034] The splitting 4a,b of the sensor allows the use of smaller sensors since they will each only have to process half of the thrust on the pad 2. This pair of sensors 4a,b can be combined with a rotation sensor 7 to detect the pivoting movement of the pad 2 by that of the axis 21 with which the pad 2 is integral and provide a control signal.

[0035] Generally, the single or double force sensors 4 can be combined with a rotation sensor 7 or a stroke sensor 8 or their combination depending on the desired level of redundancy. The signals S1, S1', S2, S3 are processed by the circuit 15 which provides the processed signals to the central unit 6.

[0036] NOMENCLATURE OF MAIN ELEMENTS

[0037] 100 Control device

[0038] 200 Control device

[0039] 300 Control device

[0040] 400 Control device

[0041] 1 Base

[0042] 11 Top / cover

[0043] 12 Landing

[0044] 13 Below

[0045] 2 Skate

[0046] 21 Axis carrying the skate

[0047] 22 Below

[0048] 23 Above

[0049] 3 Spring

[0050] 31Branch connected to the skate

[0051] 32Active branch

[0052] 321 End

[0053] 33 Torsion spring body

[0054] 4 Force sensors

[0055] 41 Soft pad

[0056] 42 Pusher

[0057] 5 Processing circuit

[0058] 6 Central unit

[0059] 7 Rotation sensor

[0060] 71 Magnet

[0061] 72 Fixed magneto-sensitive element

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071] 8 Stroke sensor 81 Pusher connected to pad 2 82 Flexible pad integrated in the base F Thrust exerted by the driver's foot SI Force sensor signal SI' Force sensor signal S2 Rotation sensor signal S3 Stroke sensor signal ST Processed signal SC Braking system control signal

Claims

Claims

1. A braking control device for a motor vehicle comprising: - a base (1), flat with bearings for an axle (21), - a pad (2) mounted on the axle (21) above the base (1), to receive the thrust (F) from the driver's foot, - a torsion spring (3) whose body (33) is freely fitted onto the axle (21) and * one branch (31) of which is connected to the pad (2) to follow the pivoting movement on the axle, * the other branch (32), active, resting by its end (321) on the top of the base (1), - a flexible plate (41) held by the top (11) of the base (1) under the bearing end (321) of the active branch (32), - a force sensor (4) under the plate (41) receiving the thrust of the active branch (32) by through the plate (41),and - a processing circuit (5) receiving the signal (SI) from the sensor (4) to process it and supply the processed signal (ST) to the central unit (6) generating the control signal (SC) applied to the braking system.,

2. Control device according to claim 1, characterized in that it comprises: - a rotation sensor (7) combined with the pad (2) to detect the pivoting movement of the pad (2) relative to the base and provide a signal (S2) transmitted to the processing circuit.

3. Control device according to claim 2, characterized by a split torsion spring (3a, 3b), associated by its respective active branch (32a, b) with a respective flexible plate (4la, b) for each of the force sensors (4a, b), to provide two detection signals (SI, SI') to the processing circuit (5).

Images