DE102006007072B3 - Device for mechanical release of motor-operated parking brake for motor vehicle has drive mechanism between cage and drive shaft designed so that their relative movement effects rotation of drive shaft in first rotational direction - Google Patents

Abstract

The device for mechanical release of a motor-operated parking brake for a motor vehicle has a drive shaft for releasing the parking brake in a first rotational direction, a cage (30) which encloses at least a part of the drive shaft, a drive mechanism (90,95) between the cage and drive shaft designed so that a relative movement of the drive shaft and cage in relation to each other in at least one basically axial direction of the drive shaft effects a rotation of the drive shaft in the first rotational direction, and a first device to prevent rotational movement of the cage in the housing.

Description

The The invention relates to an auxiliary unit for the mechanical release of a motor-operated parking brake for a Motor vehicle, in particular a motor-operated parking brake for a motor vehicle.

motor actuated Parking brakes for motor vehicles have been around for a long time Time established in the motor vehicle construction, because they over usual solutions, in which the parking brake over cables over a Lever on the center tunnel of the car was actuated, significant benefits to have. Across from the purely mechanical solution They have the advantage that on the center console no handbrake lever needed will that no long cables have to be relocated the elaborate constructive measures require and appropriate maintenance during maintenance entail. Furthermore, electrically operated parking brakes in the motor vehicle the advantage of being independent From the effort by the operator, a uniform effect on the brake unfold.

adversely is however in these electric or motorized parking brakes, that in a power failure in the electrical system of the car no motor activity to release the brake more possible is. Because of this, constructive measures are required in the Emergency to enable the release of the parking brake.

Usually have motor-operated parking brakes in the motor vehicle a transmission gear, which the rotational movement of a drive motor in a translational movement for the operation of associated brake cables implements. Known devices for the mechanical release of a motor operated Motor vehicle parking brake therefore provide it, in the area of a Rotary movements exporting Drive mechanism of the parking brake, for example, a starting point for an additional tool provided. By means of a hexagon socket can at this point by external influence over the Driver of the motor vehicle who places a special tool there in an emergency, the parking brake to be released. More comfortable measures For example, a bending wave may attack at a suitable point and over this bending shaft a rotational movement of the drive mechanism of the parking brake can be passed on.

Mechanically less expensive or at least greater demands causing measures provide it under tensioned brake ropes, when tightened Parking brake, the brake cable is mechanically relaxed. this happens for example, by a latch mechanism, which has a Train can be released. By this release device, the brake cables, or one of the brake cables are jerked mechanically relaxed. The stored in the brake spring force then leads to the release of the parking brake in case of emergancy.

From the European patent EP 0710595 B1 An electric parking brake for a motor vehicle is known. In this electric parking brake threaded rods or threaded sleeves are set in rotation and move through a caused by this rotational translation translation attachments of the brake cables. So can be done via an electric motor, the mechanical operation of the parking brake. In one direction of rotation of the motor, the parking brake is locked in the other direction, it is released. In this parking brake mechanics for sudden relaxation of the brake cable is provided for emergency. It is for example attached to a guide sleeve on the housing of the adjusting mechanism for the brake. It holds a brake cable under tension and can be moved by a train. On her guide along the train, which she passes through the train, she can be released and slide into the interior of the housing. As a result, the brake cable is relaxed jerky and released the brake under the spring action of the brakes.

These in the prior art disclosed release mechanism for an electric However, parking brake has the disadvantage that this jerky release of under train standing brake cables high mechanical stresses brings with it and after repair of the electrical system of the vehicle complex mechanical activities required to the electric parking brake and the so connected mechanical parts of the parking brake again feasible close. The parking rope must be replaced by a calibration drive be latched.

The document DE 10 2004 030 939 A1 describes an actuator of a parking brake with an electric motor. To release the parking brake arranged on a drive shaft toothed pulley is rotated by a cable.

The document DE 197 10 602 A1 describes an electromechanically actuated parking brake system with an auxiliary actuation device that allows an alternative operation of the parking brake in case of failure of the electrical system.

The document DE 100 15 263 C2 describes an electromechanical braking device for a motor vehicle. In this case, an electromechanical service brake and a mechanically actuated auxiliary brake which can be coupled with a de-energized electromechanical service brake are provided.

The The object underlying the invention is to provide an improved Device for mechanical release a motor-operated vehicle parking brake indicate which of the above-described disadvantages of the prior art technology overcomes and in particular ensures trouble-free operation in case that the electrical system of the car fails and the parking brake after repair of the vehicle electrical system again to be put into operation.

These The object is achieved by a device for the mechanical release of a motor-operated parking brake according to claim 1 solved.

advantageous Further developments of the invention will become apparent from the dependent claims 2 to 13.

Especially is advantageous in a device for the mechanical release of a motor operated Car parking brake according to the invention a drive shaft by tensile or compressive action in rotational movements offset, which can then be used directly to one for motor activity the parking brake existing transmission gear drive. In this way, the mechanical stresses Minimized and technically particularly advantageous in the field of brake cables the problem is solved, that no jerky stresses when releasing the parking brake in the Emergency should occur. Thus, the mechanical stresses be kept low in the brake cables, giving a total to a higher one reliability of the parking brake system leads.

Advantageous In a further development of the invention, a relative movement between a housing or cage a drive shaft and the drive shaft utilized to the drive shaft to turn in rotational movements. In this case, the cage is advantageous in his Rotation, for example, hindered by a square fit, or by a different mechanical solution, for example an oval fitting, the one turning the cage prevents, where appropriate, a simultaneous axial displacement or the cage allowed the wave.

Advantageous In a further development of the invention, the drive mechanism, which a relative movement between a cage of the drive shaft and the Drive shaft converts into a rotary motion, so constructed that two complementary interacting with each other constructed profiles, the first profile on the cage is arranged and the second profile on the drive shaft. Especially can be advantageous through this design according to the mechanical Strength requirements of the shaft and cage either grooves or tenons be used as profiles and attached to a suitable location become.

Especially Advantageously, a development of the device according to the invention for mechanical release second means on which the first and the second profile in the direction of rotation across from the cage fix so that they transmit force in the first direction of rotation.

On this way becomes a solvable one Connection provided in the case of starting the motor actuated Parking brake in an emergency actuation of the mechanism only in the reverse direction, contrary to the locking direction allows. At the provision the release mechanism is so advantageous ensured that no Force from the shaft to the cage or transfer the housing becomes.

Especially advantageous are the profiles for power transmission in the device according to the invention designed in a development so that at axial displacement of the cage and the drive shaft relative to each other a force against a weird one Flank occurs, resulting in a resultant torque in the direction of rotation the drive shaft is generated.

A such effect can be achieved for example by a circumferential annular groove, a circumferential drive coil or a heart curve can be achieved which is moved against fixed pins. It is advantageous in this Connection to pay attention that the slope of the oblique flank so chosen is that the effort and the torque generated in appropriate Related to each other, so that the parking brake under reasonable force solved by a person can be.

Advantageous are the second means in a development of the device according to the invention for Solve the Parking brake designed as a freewheel, because freewheels conventional mechanical solutions represent, as known for example by the bicycle, only To transmit drive torque in one direction while they at the same time create a secure mechanical bond, which is a high long-term reliability guaranteed.

Advantageous are in a development of the device according to the invention for the mechanical release of Parking brake the second means in the form of a Mitnehmerrades realized, which can be latched into an end-face internal toothing of the cage is and has the first profile.

It is advantageous in a development of the device according to the invention between the cage and the housing of the device for the mechanical release of the parking brake, a spring is arranged, which is biased relative to each other during a relative movement of the cage and the drive shaft and a counterforce that can be used to return the device.

By the spring action can also be guaranteed be that cage and the case being held together in a first position, in which they remain at rest.

Advantageous it provides a development of the device according to the invention that the Profiles are designed so that the profiles in the first position do not interact. In this case, it is particularly advantageous possible, the device according to the invention force fit with the drive mechanism, i. the actuating mechanism of the parking brake to couple, being in the first position even with an electric or other mechanical actuation of the parking brake the device according to the invention mitbetätigt and by not being coupled, is freely movable, so no mechanical couplings are required in this case.

Advantageous it provides a development of the device according to the invention that the Relative movement between the cage and the drive shaft of the device is generated by a train, because trains economical are manufacturable and reliable solutions in the Range of vehicle construction.

Advantageous it provides a development of the device according to the invention that the Mitnehmerrad is axially displaceable, the axial movement play is so big that in the axial direction, the first and the second toothing releasable are.

On This way, a mechanically cost-effective solution is advantageous Coupling of the profiles and thus the rotational movement created for the drive and to solve the electric parking brake is required in an emergency.

Advantageous becomes the axial displaceability of Mitnehmerrades in a development the device according to the invention by an axial locking ring allows the axial displacement in relation to the cage limited. Circlips are mechanically simple, represent cost-effective standard solutions and bring with it advantages in the field of assembly of the device yourself.

Especially is advantageous in a development of the device according to the invention the drive shaft of the device at the same time the drive shaft a motor-operated parking brake, so no additional Coupling component for coupling the device to the parking brake is required. In the manufacture of the parking brake is advantageous only a longer one Build up a wave that contains the additional, for the Drive shaft of the device has required components.

It Thus, at the same time, this results in a simple mechanical coupling created the device with the drive of the electric parking brake and also a cheap one Manufacturing process for this Contraption.

in the Following, the invention will be further explained with reference to figures.

1 shows a motor-operated parking brake for a motor vehicle according to the prior art.

The 2 and 3 show a front and a side view of an embodiment of the mechanical device for releasing a motor-operated parking brake according to the invention.

4 shows a detail view of the cage of an embodiment of the invention.

5 shows an exploded view of a detail of the device according to the invention.

6 shows an enlarged view of the Mitnehmerrades and the cage of the device according to the invention.

7 shows a sectional view taken along the central axis of the drive shaft of an embodiment of the invention.

8th shows an enlarged sectional view in the region of the end face of the cage of a device according to an embodiment of the invention.

1 shows an actuator 11 for an electrically operated parking brake of a motor vehicle according to the prior art. In the brake according to the prior art is in the actuator 11 a drive motor 2 available, via utility lines 9 is controlled. The drive motor 2 drives via a drive shaft 8th a drive pinion 1 a transmission gear, which with a gear tooth 3 is toothed, which on threaded rods 4 and 6 whose threads are in opposite directions, acting and set these threaded rods in rotation of the motor in rotation. The rotation of the threaded rods on actuation of the motor leads depending on the direction of rotation for retraction or extension of the brake cables 5 and 7 in the directions indicated by arrows Zugrichtungen 51 and 71 , The threaded rods move in one direction of rotation 4 and 6 the fastenings conditions of the brake cables 5 and 7 so that these are inside in the housing of the actuator 11 retract and tighten the brake cables. In the other direction they give the Brake cables free again.

A mechanical release device for releasing the motor-operated parking brake according to the prior art sees it in the region of the brake cable 5 before that this can be released by a displacement of the attachment and the under train brake cable is released jerkily, causing the threaded rods 4 and 6 in the gearbox 3 are freely axially displaceable, move to the right and so in the direction of the arrow 71 and thereby also the brake cable 7 release. A restoring force is generated in this case by the brake springs of the parking brake.

2 shows a front view of an embodiment of the inventive device for releasing a motor-operated parking brake 10 , The device has a housing 20 on, a cage 30 , a circlip 40 , a drive pinion 60 and a drive shaft 70 , Between the case 20 and the cage 30 is a spring 50 arranged so that they are at an axial displacement of the cage 30 a restraining force in the direction of 2 shown starting position causes.

3 shows the in 2 illustrated embodiment of the device according to the invention in a side view. In this connection, it should be mentioned that components of identical design of embodiments of the device according to the invention are designated by the same reference numbers throughout all figures. The drive shaft 70 the embodiment of the device according to the invention can in example directly with the drive shaft 8th be coupled to the device of the prior art or form a mechanical unit with this drive shaft, so that the device according to the invention directly to the motor shaft or other drive shaft of the device according to the prior art, which in 1 is shown, can produce a rotational movement. How out 3 It can be seen further on the cage 30 a pull rope 80 attached, with the cage viewed from the front in 3 can be pulled to the right. This movement is required in the example shown here, if in an emergency, the motor actuation of the parking brake fails and a mechanical solution of this parking brake is required.

The use of a pull ropes 80 to generate the movement represents a simple structural measure. There are also other actuating means such as rods, hydraulic or pneumatic cylinders conceivable.

4 shows a detail of the embodiment of the device for mechanically releasing a motor-driven parking brake for a motor vehicle according to an embodiment of the invention. Here are the details of the cage 30 and the pull rope 80 to recognize, which may for example be designed as a Bowden cable to effect an axial movement of the cage. Out 4 is clearly a square as Arretierungsbauteil in the illustration 35 to recognize the cage 30 in the case 20 ensures against rotation, so that a torque through the mechanical functional parts of the device according to the invention on the drive shaft 70 can be generated.

5 clearly shows an exploded view of constituent parts of an embodiment of the device according to the invention. In particular, here is the drive shaft 70 to recognize the pinion 60 , a diluted lot of the wave 65 that does not have a first profile in a first section and a part of the drive shaft that has a first profile 75 having. Furthermore, the retaining ring 40 to recognize and the Mitnehmerrad 90 , as well as the cage 30 and the pull rope 80 , It is clear in the area of the Mitnehmerrades 90 also journal 63 to recognize. The journals 63 the Mitnehmerrades 90 act with the journal surface 65 , or the drive surface 75 the drive shaft 70 together when the device according to an embodiment of the invention is actuated to trigger the mechanically actuated release of the electrically operated parking brake.

In the illustration in 5 the profile on the shaft is designed so that it surrounds this like a spiral, and the profile parts on Mitnehmerrad are configured as pins, with the profile on the drive shaft 70 work together. However, it will be apparent to one skilled in the art that the reverse arrangement with respect to the follower wheel and shaft is also possible, ie, pins could be present on the shaft, and a corresponding scroll or runner could be located on the follower wheel, and it would the same effect can be achieved.

6 shows an enlarged view of the cage 30 and the Mitnehmerrades 90 , Clearly in the area of the cage 30 on its front side an axial internal toothing 38 to recognize and in the range of Mitnehmerrades 90 a frontal toothing 95 , Preferably, the toothing pairing 95 . 38 designed as helical teeth. The helical gearing allows improved power transmission in the direction to release the parking brake. In the opposite direction in the provision of the mechanism for releasing the brake in its resting state, it promotes a rapid separation of the teeth and also prevents a transmission of force in this direction. Also clearly visible in the illustration parts of the first profile in the form of drive pin on Mitnehmerrad to recognize with 63 are designated. The Mitnehmerrad 90 will be in In neren of the cage 30 mounted, the circlip 40 is removed during assembly. Then it passes through the opening in the area of the front side of the cage 30 pushed through, after which the retaining ring 40 at the Mitnehmerrad 90 is attached. This locking ring has an axial position, which is the Mitnehmerrad 90 allowed to be moved axially with respect to the end face or the shaft of the drive axle, so that at least one release of the toothing 95 and the gearing 38 is possible.

7 shows a sectional view of an embodiment of the device according to the invention in the longitudinal direction. It is the drive worm with a tread 75 to recognize the pull rope 80 , the journal 63 , the tread 65 , the driving wheel 90 and the drive shaft 70 , Especially you can go out 7 recognize that the teeth do not latch, and that the pins 63 run in the area of a tread that allows no drive and where no torque between the shaft and the cage would be transmitted, even in the case where there would be a coupling of the frontal toothing of the cage with the toothing of Mitnehmerrades.

Like, for example 2 can be seen, is the drive shaft 70 in the area of the drive pinion 60 axially fixed. If now the cage 30 to describe the function via train in the area of the pull rope 80 to the rear, ie to the left in 6 is drawn, so first the frontal interlocking of the cage 30 , with 38 is designated, and the frontal toothing 95 the Mitnehmerrades 90 engaged with each other, as the cage moves in the direction of the Mitnehmerrades and thus engage the teeth. Another move on the pull rope 80 causes the journal 63 against the drive flank 72 the drive worm on the drive shaft 70 are pressed and thus the gears 95 and 38 Strongly couple with each other because they have the drive shaft 70 in cooperation with the drive flank 72 and the journal 63 be compressed. With respect to the pins, the inclined drive flanks 72 the drive worm is an inclined plane, the one from the tensile force in the direction of the rope 80 Resulting force across the drive shaft, which causes the drive shaft with sufficient train in rotation. Because the cage is prevented in its rotational movement by passing through the square or the Arretierungsbauteil 35 secured in the housing, which could for example be designed as an oval, or could be realized by guide pins or the like, in grooves in the housing 20 engage only the drive shaft in response to the transverse force caused by the train 70 set in rotation, as the transverse force by acting on the edge of the drive screw 75 in a torque on the drive shaft 70 effect. That is, by a further translational movement of the cage 30 to the left in 7 in the direction of the pull rope 80 run the journals 63 along the screw of the drive shaft and enable the drive shaft along its path by the transmitted tensile force in rotation. Care must be taken to ensure that friction between the journal and the drive shaft in the area of the worm is taken into account accordingly and that the pitch is chosen so that the force exerted by the tension cable 80 and the required number of revolutions for the release of the parking brake suitably dimensioned and matched.

Proper sizing may also mean that the cage is made longer, and the length of the swept profile is increased in the translational movement, so that less force, or a greater number of turns of the shaft, can be realized. At the same time, it should be noted that, as also in 3 represented by translational movement of the cage 30 the feather 50 opposite the housing 20 is biased. If the drive pin has swept over the entire drive profile present on the shaft, for example a drive screw, a stop is achieved, for example, and the operator releases the cage again, for example by releasing or releasing the pull or the like. The cage is moved by the spring to the right in relation to 7 pressed, this causes that again the journal of the Mitnehmerrades 90 against the screw profile on the drive shaft 75 abut and in this connection, because of the axial displaceability of the Mitnehmerrades in the region of the front side of the cage, the teeth 95 and 38 decoupled by the pressure on the journal and when sliding back the cage to the right in 7 only the Mitnehmerrad 90 rotates without transmitting torque to the cage from the shaft.

8th shows an enlarged example of a sectional view of an embodiment according to the invention. It's the cage 30 shown, the journal surface 65 , the Mitnehmerradverzahnung 95 , the cage front 33 and the circlip 40 and positions 110 represented. The distance between the positions 100 and 110 is dimensioned so that the frontal toothing of Mitnehmerrades 95 and the frontal toothing of the cage 38 at the indicated by these positions axial maximum displacement of the driving wheel relative to the cage are not engaged, so that the teeth can decouple when the device, ie the cage after release, ie release the electrically operated mechanical parking brake, back to its original position the feather 50 is returned.

A person skilled in the art is aware that on the frontal toothing of the cage 38 and the Mitnehmerrades 95 can be omitted if instead a not shown from the bicycle area known freewheel is used, which only allows the transmission of torque between the shaft and cage in one direction, which must be the drive direction for releasing the motor-operated parking brake in this case. Although such a freewheel is more expensive, it has the advantage that it is not exposed to so much wear during frequent use as the spur gear solution.

In this context, it should be noted that the invention has now been described only in the form of an embodiment, but that modifications are possible within the scope of the stated principles. For example, the translational motion rotation may be generated over a curve other than a constant pitch helix, such as a heart curve. The profiles may have other pitches or may be smaller, they may be inversed or otherwise. It is also conceivable that not the cage is displaceable, although this should represent the most favorable principle in practice, but that the drive shaft 70 is coupled to a driven shaft of the motor-operated parking brake so that the shaft of the device 70 is axially displaceable, and instead of the cage, the drive shaft is made axially displaceable. As a result, the same effect is achieved by a technically more complicated embodiment of the mechanical arrangement, without the principle of the invention being impaired. In this case, however, the coupling solution between the parking brake of the vehicle and the device for the mechanical release of the parking brake would be more complex. For example, the rotational movement would then have to be transmitted via a hollow shaft, which allows an axial displacement of the drive shaft therein. The relative movement could be generated for example via a push rod, which exerts pressure on the drive shaft at the free end.

Claims (13)

Contraption ( 10 ) for mechanically releasing a motor-operated parking brake for a motor vehicle comprising: - a drive shaft ( 70 ) for releasing the parking brake in a first direction of rotation; - a cage ( 30 ), which at least a part of the drive shaft ( 70 ) surrounds; - a drive mechanism ( 63 . 75 . 90 . 38 . 95 ) between the cage ( 30 ) and the drive shaft ( 70 ) which is configured such that a relative movement of the drive shaft and the cage to each other in at least one substantially axial direction of the drive shaft ( 70 ) causes a rotation of the drive shaft in the first direction of rotation, wherein the cage ( 30 ) in a housing ( 20 ) is arranged axially displaceable; and - first means ( 35 ) are provided to prevent rotational movement of the cage in the housing. Device according to Claim 1, in which the first means are in the form of a square ( 35 ) are configured. Device according to one of the preceding claims, in which the drive mechanism ( 63 . 75 . 90 . 38 . 95 ) is constructed so that at least two profiles cooperate positively for transmitting power, wherein a first profile ( 63 . 90 . 38 . 95 ) at least indirectly force on the cage ( 30 ) and a second profile ( 75 ) Force on the drive shaft ( 70 ) transmits. Device according to claim 3, wherein the second means ( 90 . 38 . 95 ) are present to the first ( 63 ) and the second profile ( 75 ) in the direction of rotation relative to the cage, so that they transmit power in the first direction of rotation. Device according to one of claims 3 or 4, in which the second profile ( 75 ) is arranged substantially on the surface and in the axial direction of movement of the drive shaft ( 70 ) a slope ( 72 ) in cooperation with the first profile ( 38 ) a resultant force in the first direction of rotation of the drive shaft ( 70 ) generated during relative movement. Device according to one of claims 4 to 5, wherein the second Means are designed as freewheel. Device according to one of claims 4 to 5, wherein the second means as Mitnehmerrad ( 90 ), which has the first profile ( 63 ), wherein the Mitnehmerrad has a first toothing ( 95 ), which in the axial direction of the drive shaft with a second toothing ( 38 ) on the cage ( 30 ) can be coupled. Device according to one of claims 1 to 7, wherein between the cage ( 30 ) and the housing ( 20 ) a feather ( 50 ) is arranged so that it is tensioned during the relative movement, so that it cage ( 30 ) and housing ( 20 ) in the relaxed state in a first position holds. Apparatus according to claim 8 in conjunction with claim 4, wherein the profiles ( 63 . 75 ) are designed so that they do not interact in the first position. Device according to one of claims 1 to 9, comprising a traction cable ( 80 ) has to pull operation, wherein a train on the traction cable a relative movement between the drive shaft ( 70 ) and the cage ( 30 ) generated. Device according to one of claims 7 to 10, wherein the Mitnehmerrad ( 90 ) in the cage ( 39 ) is arranged axially displaceable, wherein its axial movement play ( 100 . 110 ) is dimensioned so that the first and second gearing ( 38 . 95 ) are releasable. Apparatus according to claim 11, in which the axial movement through a locking ring ( 40 ) is limited. Device according to one of the preceding claims, wherein the drive shaft ( 70 ) as well as drive shaft ( 38 ) of the motor-operated parking brake is designed.