DE102006030565A1 - Self-energizing brake i.e. wheel brake, operating method for motor vehicle, involves triggering emergency releasing device by safety system e.g. anti-block- and/or electronic stability program-system, during operation-opening of brake - Google Patents

Abstract

The method involves providing a brake lining (1), a brake disk (3) and an actuator (31), which pushes the brake lining at the brake disk and loosens the brake lining from the brake disk. A wheel brake (18) is emergency opened by a detachable emergency releasing device (12), which is switched from an operation braking position into an emergency releasing position. The emergency releasing device is triggered by a safety system e.g. anti-block- and/or electronic stability program-system, during operation-opening of the brake. Independent claims are also included for the following: (1) an application of an emergency releasing device of a brake for improving the releasing dynamics during operation-opening of the brake (2) a computer program product with program code units, which, when executed on a computer or a releasing system for releasing of an emergency releasing device to implement a method of operating a self-energizing brake for a motor vehicle.

Description

The The present invention relates to a method for operating a Brake with an emergency release device and a corresponding brake according to the preambles of the independent claims. The The present invention further relates to a computer program as well a computer program product.

State of the art

Even though in the following essentially self-reinforcing electromechanical brakes in vehicles, the invention is not thereon limited. It affects everyone equally Brakes, where a high release dynamics he wishes is.

Self-energizing electromechanical brakes usually comprise an electrically actuated actuator (brake actuator), usually an electric motor, which presses or releases a first brake element or friction element with a friction lining against a second element to be braked, for example a brake disk. In a brake operation, the friction member is entrained by the kinetic energy of the element to be braked and amplifies the braking effect automatically (self-energizing). A trained as a wedge brakes self-energizing electromechanical brake is eg in the DE 198 19 564 C2 described.

comes For example, the wheel of a vehicle during a full braking with maximum braking torque suddenly high from a road surface Coefficient of friction (e.g., dry asphalt, N = 1.2) on a surface very much low coefficient of friction (e.g., black ice, N = 0.15) blocks the wheel within a few milliseconds. The blocking of the wheel leads to a unstable, critical vehicle condition and must therefore be lifted as soon as possible become. Therefore are common in a vehicle Security systems such as ABS or ESP provided. driving dynamics calculations assume a maximum blocking time of 40 ms to indicate an instability or a To avoid skidding of the vehicle. Within this time should the wheel brake, usually controlled by ABS or ESP systems solve.

current Hydraulic and under development electric brake systems or systems are at most capable of a release dynamics of about 80 ms at full application force. In the development electric brake systems requires the high release dynamics requirement on the one page big Electric drives with high power consumption and low gear ratios, whereas on the other hand, the demand for small battery power and low mass of the actuator after small electric motors with large gear ratio demands, which leads to a significantly reduced braking dynamics. Out this reason can in electric brake systems hardly release dynamics above that of hydraulic brake systems are achieved. Instead, one is electric brake system at high saddle forces tends to be a hydraulic inferior. Previous approaches to solution this problem in the 12 volt range are not known. For 42 volt systems be big engines with big ones Power consumption used.

It Therefore, the task is to improve the release dynamics of a brake. According to the invention a method, a brake, a computer program and a computer program product with the characteristics of the independent Claims presented. Advantageous embodiments are the subject of the dependent claims and the following description.

According to the invention Release dynamics through Using an emergency release device elevated. at a brake, in particular self-reinforcing and / or for a motor vehicle, with a triggerable emergency release device for emergency opening the brake, in which the emergency release device from a service brake position to an emergency release position transitions or is the emergency release device while a business opening triggered. operation Open becomes in the sense of this invention as demarcation and contrary to usual Emergency opening Understood. The brake is at a service opening in a normal operation or state. A company opening is therefore particularly planned and wanted.

By This measure becomes the release dynamics a brake advantageously increased. This increase is common only with service braking, by a security system, eg. ABS or ESP system, in critical or dangerous Triggered situations be desired or necessary, but can also be quite general for all service braking be used. The invention is in all brakes with a emergency release or a device corresponding to an emergency release device is usable, especially in vehicles, usable.

Emergency release devices known from the prior art are intended to be used in the event of serious misconduct, such as, for example, an accident. As a power failure or a mechanical defect completely reduce the clamping force of the brake. They are not used during service braking. An emergency release device, for example, by means of a provided Notlöseaktuators or electric motor a certain service brake position. In the event of a fault, it usually automatically transitions into an emergency release position, for example, under the action of force the brake is fully open. After an emergency release, the brake is no longer usable until the emergency release device by the driver or user manually or in a workshop is brought back to the service brake position. It is understood that a device is always to be regarded as emergency release device, if it is in the sense of this invention to effect a rapid reduction of the clamping force, in particular by a change in length, in particular shortening, kraftbeaufschlagter components in the power flow. In particular, it is not necessary for the realization of the invention that the emergency release device is also provided for emergency release of the brake or actually used for this purpose.

at instead of the present invention, the emergency release device in the case of high required release dynamics together with or operated alternatively to the main drive or triggered. this leads to to a much shortened Release time. The triggering can be done in particular by means of an electrical signal.

To or during of triggering the emergency release device opens the Main drive the brake and the emergency release, which reversible accomplished is, can be returned to the service brake position become. The default needed about 50-100 ms, meanwhile no braking of the affected wheel is possible. But this is under Safety issues less critically than a hurling Vehicle, especially as a rule during this time at least two more wheel brakes are engaged.

It is appropriate if the emergency release device is triggered by a security system, in particular ABS and / or ESP. It is understood that as well other systems or control devices Tripping can be provided.

advantageously, becomes the emergency release device when crossing triggered at least a predetermined threshold. It lends itself to a threshold for one Target-difference specify the brake application of the brake, in which case only when exceeded of the difference threshold and, if desired, additionally at a predetermined one Demands on the release dynamics the emergency release device is triggered.

It lends itself to that the emergency release device is triggered by an internal brake system. This system can receive the request from other vehicle components or systems, a certain clamping force within a certain period of time provide. The system decides on the basis of the received Parameters and data, eg. Current clamping force, friction coefficient, etc., whether to fulfillment the request the emergency release device triggered should or should not be.

A brake according to the invention has an emergency release device and means on to an embodiment to carry out the process of the invention. The Brake is particularly self-reinforcing trained and / or for a Motor vehicle provided and has a first brake element, a second brake element, an actuator for pressing the first brake element to the second brake element and for releasing it and a releasable emergency release device for emergency opening the brake, in which the emergency release device transitions from a service brake position to an emergency release position, as well as a trigger system for Trigger the emergency release device while a business opening.

advantageously, has the emergency release device a changeable one Expansion, with a change the expansion a change the application force causes.

One Computer computer according to the invention or microprocessor program contains Program code means for carrying out a method according to the invention, when the computer program on a computer or equivalent Arithmetic unit, in particular a control unit in a motor vehicle, in particular a trigger system to trigger the emergency release device, accomplished becomes.

One Computer computer according to the invention or microprocessor program product includes program code means, stored on a machine or computer readable medium are to a method according to the invention to perform, if the program product on a computer, a microprocessor or on a corresponding computing unit, in particular a control unit in one Motor vehicle, in particular a triggering system for triggering the emergency release, accomplished becomes. Suitable media In particular, floppy disks, hard disks, ROM, flash memory, EEPROMs, CD-ROMs, u.a.m. Also a download of a program via computer networks (Internet, intranet, etc.) and vehicle networks (body bus, infotainment bus etc.) or air interfaces (mobile) is possible.

As already stated above, an application is not only possible for self-energizing brakes, but also for any electric brakes that can not open independently due to a fault or close yourself due to stored in the brake or in the vehicle energy. An example of the latter group is a brake with a member to be braked, at least one friction lining for frictional engagement handle with the member to be braked, and an electric actuator for moving the friction lining in frictional engagement with the member to be braked. Furthermore, a reversible power storage operatively coupled to the electrical actuator is provided which cooperates with a force translation device such that upon actuation of the brake by means of the actuator, the force stored in the force accumulator is successively delivered to the force translating means with increasing actuation travel of the actuator and from thereinto an actuating torque is implemented, which is transmitted directly or indirectly to the friction lining, wherein the actuating torque increases with increasing actuating travel of the actuator in a predetermined manner, and that upon release of the brake on the friction lining on the force transmission means retroactive, braking inherent restoring force recharges the energy storage , Even on such a brake as a brake, which can close even due to energy stored in the vehicle, the concept proposed in the application is applicable.

Further Advantages and embodiments of the invention will become apparent from the Description and attached drawing.

It it is understood that the above and the following yet to be explained features not only in each case specified combination, but also in other combinations or alone, without to leave the scope of the present invention.

The Invention is based on an embodiment schematically shown in the drawing and is below under Referring to the drawings described in detail.

figure description

1 shows a schematic side view of a self-energizing brake with an emergency release device according to an embodiment of the invention;

2 shows the curve of a cam 1 ;

3a shows a schematic representation of an emergency release position of the emergency release device 1 ;

3b shows a side view of the emergency release device 1 in the emergency release position;

4a shows a schematic representation of a service brake position of the emergency release device 1 ;

4b shows a side view of the emergency release device 1 in the service brake position;

5a shows a schematic representation of a parking brake position of the emergency release device 1 ; and

5b shows a side view of the emergency release device 1 in the park brake position.

1 shows a schematic side view of a self-energizing brake according to an embodiment of the invention. The actual brake mechanism is in total with the reference numeral 18 characterized. In the brake shown here 18 it is a known motor vehicle wheel brake with a movable wedge plate 2 that by an actuator 31 in the direction of the arrow A is movable to determine or release the brake.

The movable wedge plate 2 has at its front (bottom) a brake pad 1 on, against the friction surface of a brake disc 3 acts. At the back of the wedge plate 2 are several wedge surfaces 29 provided, which are located over intermediate rolling bearings 4 on an opposite wedge surface 5 support. The opposite wedge surface 5 is on a printing plate 6 arranged.

Upon actuation of the brake 18 the wedge plate moves 2 with the brake pad 1 along a through the wedge surfaces 5 . 29 predetermined trajectory, parallel and perpendicular to the brake disc 3 , The rolling bearings 4 serve in particular to reduce the sliding friction. The movable wedge plate 2 when approaching the brake disc 3 taken from this and thus pushes even stronger against the brake disc 3 (Self-reinforcement).

The illustrated wedge brake is equipped with a Nacheinstelleinrichtung and an emergency release device, here in each case as a whole with the reference numerals 7 respectively. 12 are designated. The adjusting device 7 serves to readjust the clearance, especially when brakes are worn. It may be used advantageously but not necessary in combination with the invention. The emergency release device is used for quick release of the brake in the event of a fault, such as a power failure, and according to the invention in the case of an increased Lösedynamikanforderung.

The adjusting device 7 essentially comprises a wedge 8th and a spindle 9 , The wedge 8th has an internal thread (not shown) and can be rotated by turning the spindle 9 parallel to the printing plate 6 be adjusted in the direction of arrow B. A wedge surface 26 of the wedge 8th slides on a corresponding wedge surface 27 an abutment element 10 along, attached to a caliper 11 supported. In a wedge actuation, the pressure plate move 6 and all related elements ( 7 . 12 . 16 . 17 ) in the direction of arrow C on the brake disc 3 to or from this way. By turning the spindle 9 thus can the clearance between brake pad 1 and brake disc 3 can be adjusted as desired.

The wedge arrangement also serves to divert a portion of the application force F _Z transverse to the application force F _Z. The derived force F _Q is through the spindle 9 and the emergency release device 12 in a second abutment 17 directed, with the pressure plate 6 is firmly connected. The entire arrangement, consisting of the adjusting device 7 , the emergency release device 12 and a motor drive 16 therefore moves in the direction of arrow C.

The emergency release device 12 has two cams 13 . 14 on, dealing with their curve surfaces 19 face. Between the two cams 13 . 14 are several rolling elements 15 arranged, which are held by a cage and together represent a rolling bearing. In the illustrated embodiment, axial cams are used. Optionally, but also radial cam could be used. The in the 1 left cam 14 is non-rotatable with the spindle 9 Connected and powered by an electric motor 16 driven. The other cam 13 is rotatable on the abutment 17 stored and is not driven.

The two cams 13 . 14 Depending on the operating mode, they can be rotated either against each other or together, ie synchronously. When the two cams 13 . 14 rotate against each other, the distance between the discs changes. This change in length is via the spindle 9 , the wedge 8th and the pressure plate 6 on the wedge element 2 with the brake pad 1 transfer. If the two cams 13 . 14 because are turned against at the same time, the adjusting device 7 pressed and thus adjusted the clearance.

The cams 13 . 14 have a characteristic curve with various curve segments that define different operating states of the emergency release device, namely in particular a service brake position, an emergency release position and a parking brake position. The individual curve segments are each used in the corresponding operating state of the emergency release device.

To prevent the non-driven cam 13 when the brake is actuated, there is an electromagnet 35 provided as a holding means, the cam 13 in the energized state holds. The electromagnet 35 has a bolt 36 on, in the corresponding recesses 39 the cam 13 intervenes. The bolt 36 is by means of a spring 37 biased towards the retracted position. At a shutdown of the magnet 35 or a fault, especially a power failure, the bolt 36 by means of the return spring 37 withdrawn very quickly from the detent position and gives the cam 13 free. The cam 13 can turn into the emergency release position within a few milliseconds and the brake 18 release. To trigger the brake during service braking is a trip system 30 provided with the electromagnet 35 connected is.

The left cam is activated to activate the parking brake function 14 from the engine 16 driven and starting from the service brake position II twisted until the cams turn 13 . 14 in the park brake position I are located. By further turning the discs - with both cams 13 . 14 turn synchronously - can the brake 18 be more tense. The non-driven cam 13 in this case it is the electromagnet 35 enabled to allow rotation.

The drive of the cam 14 includes in the present embodiment, a motor 16 with only a single gear, preferably as a worm gear 38 . 40 is realized. The wave 40 of the motor 16 is provided with a worm thread, which in a corresponding toothing 38 on the outer circumference of the cam 14 intervenes. An advantage of this embodiment is, in particular, that in the case of targeted or caused by a fault triggering only the aborted cam 13 must turn. The emergency release is due to the low moment of inertia of the cam 13 much faster than in other possible embodiments, which include a transmission and the engine 16 must be turned to release the brake. An additional support of the emergency release by a biasing device, such as a spring, may also be provided here, but is not required.

When requesting increased release dynamics during service braking, the emergency release device is triggered 12 the trigger system 30 activated, that the electromagnet 35 de-energized. The bolt 36 then gives the cam 13 free, which can rotate within a few milliseconds, bringing the emergency release device in the emergency release position and the brake 18 will release. Essentially at the same time or after, the main drive or actuator opens 31 the brake 18 , When the brake 18 through the actuator 31 has been opened completely or at least so far that a Reinitialisieren or closing the emergency release device does not apply to the brake disc 3 through the brake pad 1 causes more, the emergency release device 12 brought back to the service brake position (reinitialized).

Reinitializing the emergency release device 12 starts from the emergency release position (cf. 3b ). The left cam 14 gets off the engine 16 driven in the direction in which the cam 13 is turned (left in 3b ). The rotation of the two cam discs 13 . 14 takes place until the cam disk 13 again reached the position she had taken before triggering. Subsequently, the cam disk 13 from the electromagnet 35 determined and the cam 14 in another direction (cf. 4b ) Turned back until she also takes the position before the triggering again. Thus, the emergency release device is again in the service brake position and the initialization is completed. The brake is available again.

2 shows an example of a curve 19 one of the cams 13 respectively. 14 , As can be seen, the curve includes 19 several segments 20 - 25 in different modes of the brake 18 be used. This curve 19 Repeats several times periodically along the circumference of a cam 13 . 14 wherein each period is a rolling element 15 , preferably a ball, is assigned. (In the present example, however, there are several rolling elements 15 shown to the main operating positions of the cam discs 13 . 14 The essential positions are a parking brake position I , a service brake position II and an emergency release position III , In this case, the emergency release device is, for example, in the emergency release position III when the rolling elements 15 on both cams 13 . 14 in the segments 20 are located etc.

In normal operation, the rolling elements or the rolling bearing 15 and the cams 13 . 14 in the service brake position II arranged. The rolling bearing 15 is on a segment 21 in the direction of the emergency release position III is inclined. The slope of this segment 21 is chosen so that at axial load on the cams 13 . 14 acting torque much lower than the breakaway torque of the spindle 9 is. This will prevent the spindle 9 during a braking operation rotates. The slope of the segment 21 may be for example about 1 °.

To move from the service brake position II in the parking brake position I to get to, is the cam 14 from the engine 16 driven accordingly. The rolling bearing 15 runs over a curve segment 22 and the emergency release moves to the park brake position I , The movement increases the distance between the cams 13 . 14 , causing the brake 18 becomes increasingly tense. The segment 22 has a slightly larger slope than the segment 21 , which can be for example 1.2 °. The slope of the transition segment 22 is relatively uncritical, but it should be ensured that the rolling elements 15 can get into the parking brake position in the course of the application movement.

In the parking brake position I is the associated segment 23 the curve 19 designed such that substantially no torque on the cams 13 . 14 acts. The curve segment 23 has the form of an energetic minimum or a kind of catch mark, in which the rolling bearing 15 can rest. One to the segment 23 adjacent curve segment 25 on the other hand has such a high pitch that the breakaway torque of the spindle 9 is clearly exceeded and the spindle 9 turns when the cam 14 from the engine 16 is driven. This allows the two discs 13 . 14 be turned together. The curve segment 25 forms a stop for the rolling elements 15 ,

On the service brake position II follows in the other direction an emergency release position III , The associated segment 20 has the form of an energetic minimum. In this state, the distance between the cam discs 13 . 14 minimal, leaving the wedge 8th (please refer 1 ) can move far to the right and the brake 18 completely releases. The contour of the segment 20 is preferably designed so that the brake 18 can not be stretched even at maximum actuation.

When triggering the emergency release device gives the electromagnet 35 the cam 13 free, so that the cam 13 opposite the cam 14 automatically twisted. The rolling bearing 15 rolls over the segment 24 into the emergency release segment 20 , This can happen within a few milliseconds. The slope of the segment 24 is chosen so that the change of the emergency release device in the emergency release position III runs very fast. The slope can be for example 25 °.

The 3 to 5 show the position of the cams 13 . 14 in the individual positions I to III , It is in 3a first the emergency release position III shown. As can be seen, the rolling element is located 15 between opposing emergency release segments 20 the cams 13 . 14 , The minimum distance h1 of the cam discs 13 . 14 is preferably a few millimeters, for example about 6 mm, lower than in the service brake position II ( 4a ). 3b shows an associated side view of the cams 13 . 14 in which the cams in the emergency release position III are located. The curve ben 13 . 14 have locking lugs 28 on who are in the emergency release position III apply mutually and another mutual twisting of the cams 13 . 14 about the emergency release position III prevent it from happening. By applying the cam can 13 with the cam 14 be rotated when the emergency release device is reinitialisiert.

4a shows the service brake position II the cams 13 . 14 in which are the rolling elements 15 on opposite segments 21 are located. The distance h is here designated by the value h0 and by a few millimeters larger than in the emergency release position of 3a , 4b shows an associated side view of the cams 13 . 14 in which the cams in the service brake position II are located.

5a finally shows the parking brake position III the cams 13 . 14 , The rolling elements 15 are located between opposite sections of the curve 23 , Compared to the representation of 4a has the distance h of the two cams 13 . 14 increased again and has a value h2, which is preferably something (up to a few millimeters, eg 0.7 mm) greater than h0. 5b shows an associated side view of the cams 13 . 14 in which the cams in the parking brake position I are located.

It is understood that the brake and emergency release device shown only by way of example and not intended to be limiting. Likewise, can be different designed brakes or emergency release devices with or without adjusting mechanism, which also directly in the power flow can be arranged become.

1

brake lining

2

wedge plate

3

brake disc

4

roller bearing

5

wedge surface

6

printing plate

7

Nacheinstelleinrichtung

8th

wedge

9

spindle

10

Abutment element

11

caliper

12

emergency release

13 14

cams

15

rolling elements

16

drive

17

abutment

18

brake

19

curved surfaces

20-25

segments

26

wedge surface

27

wedge surface

28

locking lugs

29

wedge surfaces

30

release system

31

actuator

35

electromagnet

36

bolt

37

feather

38

gearing

40

wave

F _Q

derived force

F _Z

clamping force

I

Parking brake position

II

Service brake position

III

Notlöseposition

Claims (12)

Method for operating a brake ( 18 ), in particular self-reinforcing and / or for a motor vehicle, with a first brake element ( 1 ), a second braking element ( 3 ), an actuator ( 31 ) for pressing the first braking element ( 1 ) to the second brake element ( 3 ) and for releasing it and a triggerable emergency release device ( 12 ) for emergency opening of the brake ( 18 ), in which the emergency release device ( 12 ) of a service brake position ( II ) in an emergency release position ( III ), characterized in that the emergency release device ( 12 ) is released during a service opening of the brake. Method according to claim 1, characterized in that the emergency release device ( 12 ) after triggering back into the service brake position ( II ) is brought after the actuator ( 31 ) the brake ( 18 ) has solved. Method according to claim 1 or 2, characterized in that the emergency release device ( 12 ) is triggered by a security system, in particular ABS and / or ESP system. Method according to one of the preceding claims, characterized in that the emergency release device ( 12 ) is triggered when exceeding at least one predetermined threshold value. Method according to one of the preceding claims, characterized in that the emergency release device ( 12 ) is triggered by an internal brake system. Brake, in particular self-intensifying and / or for a motor vehicle, with a first brake element ( 1 ), a second braking element ( 3 ), an actuator ( 31 ) for pressing the first braking element ( 1 ) to the second brake element ( 3 ) and to release it and a triggerable emergency release contraption ( 12 ) for emergency opening of the brake ( 18 ) in which the emergency release device ( 12 ) of a service brake position ( II ) in an emergency release position ( III ), characterized by a triggering system ( 30 ) for triggering the emergency release device ( 12 ) during operation opening of the brake. Brake according to claim 6, characterized in that the triggering system ( 30 ) has a security system, in particular an ABS and / or ESP system. Brake according to claim 6 or 7, characterized in that the triggering system ( 30 ) Comprises means for comparing a value with a threshold. Brake according to one of claims 6 to 8, characterized in that the emergency release device ( 12 ) has a variable extent (h), wherein a change in the extent (h) causes a change in a clamping force (F _Z ). Using an emergency release device ( 12 ) a brake ( 18 ) to increase the release dynamics during operation opening of this brake, wherein the emergency release device ( 12 ) has in particular a variable extent (h), wherein a change in the extent (h) causes a change in the application force (F _Z ). Computer program with program code means for carrying out the steps of a method according to one of claims 1 to 5, when the computer program is stored on a computer or a corresponding computing unit, in particular in a control unit in a motor vehicle, in particular in a triggering system ( 30 ) for triggering the emergency release device ( 12 ), is performed. Computer program product with program code means which are stored on a computer-readable data carrier to perform the steps of a method according to one of claims 1 to 5, when the computer program product on a computer or on a corresponding processing unit, in particular in a control unit in a motor vehicle, in particular in a triggering system ( 30 ) for triggering the emergency release device ( 12 ), is performed.