SE514768C2 - Parking brake device, adjustable automatically, or with servo support, or muscle power - Google Patents

Abstract

A clamping brake installation has a device operated by an electric motor or by muscle force to tension the brake cables. The tensioning device (10) comprises a roller or roller segment rolling up a cable (1). The roller or roller segment has at least one toothed region (32,33) with which a driven wheel (42) of a servo drive (40) mates and in which a locking element engages which can be released to open the clamping brake and locking against the tensioning direction. The roller or roller segment can be pivoted with the help of a control element (11) whose pivot axis is identical with that of the roller or roller segment. Parallel to the switch element(20) which recognizes the operation of the control element, an electrically or electronically operated switch element controlling the servo drive is located which is released at least by a signal generated by the hill-holder-automatic device of the ABS control in a control unit.

Description

locking and for releasing the parking brake releasable locking element engages. The roller or roller segment is, by means of a control element whose pivot axis is identical to that of the roller or roller segment, pivotable in the clamping direction via a locking element which can be released to release the parking brake. In parallel with the coupling element which detects the influence of the operating element, an electrically or electronically actuatable coupling element is arranged and the servo drive device coupling element is arranged, which is triggered at least by a signal generated by the automatic holding control of the ABS control.

With this parking brake device, the parking brake can be applied either with muscle power, possibly with auxiliary power support, or fully automatically. In the first case, it is tightened purely mechanically and blocked regardless of the vehicle's electrical voltage or electronics. This is done exclusively through a direct or indirect actuation of a control element, for example the depressing of a foot pedal or the tightening of a parking brake lever. In the second case, a servo drive device actuates a clamping device for the actuable element so that the parking brake can be actuated almost powerlessly. In the third case, the electronics in the vehicle ensure that the parking of the vehicle is detected and triggers an effect of the parking brake. The parking brake is generally released by actuating a control lever.

The parking brake device has that advantage. that an intentional influence from the driver usually takes place only via a specific actuating element, eg the foot pedal. In this case, it is immaterial whether the ignition is switched on or the electrical system is defective.

In the event of a loss of servo operation, the driver only notices the absence of the auxiliary power support. He must, for example, in the event of an unfavorable driving situation, for example when stopping or starting on a slope in the event of loss of the vehicle's electronics, no longer have to look for anything special and otherwise not experience ...- \ .ß \ im \ co bad influence or coupling means with which he can initiate a mechanical parking braking of the vehicle.

In the automatic operation, the advantage is obtained that the service brake, which is affected by the automatic restraint, is not misused or overloaded. An ordinary ABS braking system1 with this automatic has the disadvantage that the service brakes are not released hydraulically after parking the vehicle. The driver can leave the seemingly safely parked vehicle without the influence of the parking brake. However, if the hydraulic pressure drops due to leakage within a few hours, the vehicle can start rolling. This is prevented in the parking brake system according to the invention, because here the parking brake device is tightened at or after leaving the vehicle in such a way that it alone can take over responsibility for the maintenance of the vehicle.

The invention is described in more detail below with reference to the accompanying drawing, in which Fig. 1 shows a tensioning device for a parking brake with its actuating means, Fig. 2 shows a tensioning device with unaffected parking brake and Fig. 3 shows the tensioning device with actuated parking brake.

Fig. 1 schematically shows the construction groups and parts required for an automatic and manual actuation of a mechanical parking brake. A central construction group constitutes the tensioning device 10 with its drive device 40. The purpose of the tensioning device is to tension a tow line 1 for tightening the vehicle parking brakes. For this purpose, line 1 is mechanically connected to the brake struts or lines (not shown here) and to the parking brakes.

In the clamping device 10, the tow line is generally wound up electrically, ie during servo and automatic operation. A servo drive device 40 is used for this purpose. This comprises an electric motor which may be equipped with a gear unit, as well as a clutch 43. The latter may be, for example, a mechanical centrifugal clutch or an electromagnetically manoeuvrable clutch. A torque sensor 45 is arranged between the coupling 43 and the clamping device 10 to be driven. With this sensor, the torque present on the output drive shaft is measured during the clamping process. It is proportional to the clamping force acting on the parking brake shoes.

The electric motor 41 in the servo drive device 40 is connected via load lines 64-67 to the positive pole of the vehicle's electrical system. Arranged in the load lines 64-66 are three coupling elements 20; 46, 47. The element 20 is a key type mechanical switch for closing, the key of which rests, for example, against the lever of the brake pedal 11 in such a way that the closing switch is open when the brake pedal 11 is unaffected.

Arranged in parallel with the coupling element 20 is an ABS coupling element 48. This coupling element, which is a closing switch, is actuated by a relay 49, which is connected via a signal line 68 to a control unit 3. In front of the two coupling elements 20, 48 a via a relay 47 which can be actuated and the switch-off element 46 designed as an opening switch. The relay 47 is connected, among other things, via a control line 67 to the control unit 3.

Furthermore, a torque sensor 45 and a switch 60 are connected to the control unit 3.

The control unit 3 contains, among other things, an ABS control equipped with a reverse holding automatic. The automatic restraint system ensures that during each braking process and vehicle standstill, the service brakes remain actuated until the steering detects a start-up process initiated by the driver.

The control signal to the automatic restraint to hold the service brakes is also used for automatic tightening of the parking brakes. For example, the control signal triggers a short-time sensor for time periods between one and several minutes. After the expiration of a predetermined or adjustable time period, the control unit 3 acts on the relay 49 and thus starts the servo drive 40.

This drive 40 tightens or tightens the brake line 1. When the torque sensor 45 has reached the torque corresponding to a sufficient clamping force of the parking brakes, the control unit 3 causes the relay 47 to open the coupling element 46. The servo drive device 40 is switched off.

The signal from the automatic restraint system can also be used in combination with signals that arise if, for example, the ignition key is pulled out, the driver's door is opened or the driver's seat electronics detect a departure from the driver's seat. The control 3 can, depending on the type of vehicle or application, be programmed for this from a combination of individual or several such signals which detect a normal parking of the vehicle in order to automatically release the parking brake to relieve the service brake as early as possible.

With the aid of the switch 60, the parking brake can be actuated directly while bypassing the automatic restraint.

By a rapid actuation of the switch 60, the servo drive device 40 is activated. This is switched off in the manner described above.

The parking brake can also be applied during servo support.

For this purpose, the foot pedal 11 is depressed. Via the switch 20, which is closed, the servo drive device 40 is started. The same stops as soon as the foot pedal 11 is released again or at the latest when the maximum clamping force on the parking brakes has been reached, cf. the automatic control.

Optionally, the switch 20 may also have the function of the switch 60.

Figures 2 and 3 show the clamping device. It comprises a roller segment 30, which can be pivoted or rotated either by means of a foot pedal 11 actuated by an inertial force or a servo drive device 40.

In this exemplary embodiment, the roller segment 30 is a disc-shaped structural part which is rotatably mounted at the vehicle body 5 via a bearing pin 30 and a bearing bracket 12. It has three outer contours. The outer contour with the smallest outer diameter is the winding contour 31. Along this is the tow line 1 coming from the parking brake. This is advanced O fi ... x F.

Ovx] Ch OI) to the clamping device 10 via a protective tube 2. The outer contour with the medium diameter is an involute gear 32. This contour engages the ratchets on the output wheel 32 of the servo drive device 40. The largest outer diameter is a series of ratchets 33. They form here part of a gear direction and a locking member. Optionally, the teeth 32 can also be used for both latches.

The foot pedal 11 is also stored on the pin 13. It is in operative communication with the roller segment 30 via a gear direction lock 17-18; 33. Gear direction lock 17-18; 33 barriers clockwise. It has a ratchet 18 which is mounted on a pin 17 attached to the foot pedal 11. The lever-like ratchet 18 is moved with spring load into the ratchets 33. At its end facing away from the tip of the ratchet it is equipped with a lever provided with a bore through which is guided by the release line 52 coming from the lever 51. On this line 52 there is a locking pawl carrier 55.

The foot pedal 11 rests against a spring element 15 wound around the pivot pin 13, omega-shaped bent element at the vehicle body 5.

The spring element 15 biases the foot pedal in the counterclockwise direction.

The pedal abuts for this purpose against a bolt 14 and at the bearing bracket 12 against a bolt 16. The latter serves at the same time as abutment for the unloaded pedal 11.

The pedal 11 can also be exchanged for a lever, which is remotely controlled by the pedal 11, for example by means of a tow line. In this case, the clamping device can be arranged at a place where there is sufficient space.

In addition, a partial lock 33 abuts the locking teeth 33 on the roller segment 30; 57-59. This contains a spring-loaded locking latch 57 which is pivotally mounted to the vehicle body 5 at a location 59. The locking latch 57 has a tip 58 whose contour from and with a certain stroke allows an automatic release. For this purpose, the tip 58 at engaging latch 57 is chamfered below the tooth outer diameter. Klinkan 57 has on CN ... x 12 :. \ l \ '] \ \ CC its free end a bore or a comparable recess through which the release line 52 is passed. This line 52 abuts the latch 57 by means of a carrier 54. The line 52 is moved behind the latch 33; 57-59 in a protective tube 53 leading to the lever 51, see Fig. 1.

In Figs. 1 and 2, a form-fitting gear lock is used for the fit and actuation of the roller segment 30. Alternatively, a force-bonded friction lock can also be used instead. Even with one, the locking device can be selected freely and the holding force is set arbitrarily.

In an automatic control of the servo drive device 40 or a depressing of the key switch 60 shown in Fig. 1 for actuating the parking brake device, the servo drive device 40 and the roller segment 30 pivot while winding the towline 1 all the way to the sensor-controlled shut-off of the electric motor 41. remains in its initial position shown in Fig. 2. The roller segment 30 rotates clockwise without obstruction of the adjacent but non-locking latches 18 and 57. After the electric motor 41 is switched off and the clutch 43 is disengaged, the roller segment rests against the vehicle body 5 via the partial lock 33; 57-59. Another support at the vehicle body 5 takes place via the gear direction lock 17-18; 33 and the foot pedal 11 through the stop pin 14.

To release the parking brake, the lever 51 shown in Fig. 1 is actuated to tighten the rope 52 in the protective tube 53.

As a result, due to the lever condition, the locking latch 18 first opens the latches 18, 57. The early opening of the locking latch 18 can also be achieved by a corresponding placement of the latch driver 54, 55 on the rope 52. In this case, before actuating the lever 51, the carrier 54 a larger play in relation to its latch 57 than the carrier 55 relative to the latch 18. The latch carriers 54, 55 may be made adjustable.

LN ..._. \ J? \ _] WCÄ C? After complete release of the teeth 33 from the pawls 18, the pawl area or bevel on the pawl tip 58 enters the main circle of the pawls 33. The roller segment 30 becomes free and rotates under the traction of the brake traction line in the counterclockwise direction. Due to the rapid pivoting movement, the locking latch 57 can no longer engage the locking device before the locking segment comes to a standstill. Consequently, a short-term actuation of the lever 51 is sufficient to achieve a complete release of the parking brake.

It is conceivable that the gear direction lock 17-18; 33 can also be designed as a partial barrier. Also, the two latches 17-18, 33 and 33; 57-59 are designed as pure pawls as long as the release force of only one pawl is greater than the effective force loading the towline 1.

In the exemplary embodiment, the release line 52 passes almost centrally through the pivot pin 13. As a result, when the foot pedal 11 is actuated, hardly any change in the free play occurs between the latches 18, 57 and their carriers 54, 55.

The clamping device can, for example, when the power supply from the electrical system is switched off or lost, be tightened with muscle force. For this purpose, the pedal 11 is actuated by the driver.

It is swung under the action of muscle force in a clockwise direction around the pivot pin 13. Through the engaging locking latch 18, the foot pedal 11 is in effective connection with the roller segment 30. The pedal 11 is depressed until the driver gets the impression that the parking brake has been applied sufficiently. The roller segment 30 and the foot pedal 11 have thereby reached the position shown in Fig. 3. After engaging the pedal 11, the engaging partial locking latch 57 prevents a reversal of the roller segment 30.

The foot pedal 11 is swung back by means of the spring element 15 until it comes to a stop against the stop bolt 14. The pedal 11 is then again in the position shown in broken lines.

(I1 Cf \ ”M-9 The release of the parking brake actuated by foot force takes place as in servo and automatic operation through the mechanical release by means of the lever 51, see Fig. 1.

In Figs. 2 and 3, the electrical switches or sensors which may be necessary for the control, for example the switch 20 in Fig. 1, have not been shown.

Claims (7)

514 763/0 P a t e n t k r a v Parking brake device with a device which can be actuated by means of an electric motor or by means of muscle force for tensioning the brake lines, wherein in the case of electric motor actuation the actuating element is released by means of an electric switch or by the electrically feasible effect of the lowest muscle force. electronically, characterized in that the tensioning device (10) comprises a roller or a roller segment (BOL) intended for winding a tow line (1), the roller or roller segment (30) having at least one row of teeth (32, 33), by means of which an outgoing driving wheel (42) for a servo drive device (40) engages and in which an interlocking or locking element (57) which can be locked or locked against the clamping direction engages, that the roller or segment (30) by means of of a control element (ll), the pivot axis of which is identical to that of the roller or segment (3 0), is pivotable in the clamping direction via a locking element (18) which can be released for releasing the parking brake, that an electrically or electronically actuatable and servo drive device (40) is arranged parallel to the coupling element (20) which detects the influence of the operating element (11). ) control coupling element (48), which is triggered at least by means of a signal generated by the automatic holding control in the ABS control in a control unit (3). Device according to claim 1, characterized in that the operating element (II) is a foot pedal. Device according to claim 1, characterized in that the locking element (57) rests spring-biased against the vehicle body (5). Device according to Claim 1, characterized in that the locking element (18) abuts 51 H against the pedal (11) during spring preloading, the latter being in its output (ffs GO 7. Read the position of the vehicle body (5). 5. Device according to claim 1, characterized in that the locking element (18, 57) can be released from the locking teeth (33) by means of a common and to a manually operable lever (51) releasing line (52). Device according to Claim 1, characterized in that a coupling element (60) is connected to the control unit (3) via which the electromechanical tightening of the clamping device (10) is intended to be triggered with a keystroke pulse. Device according to claims 1 and 5, characterized in that the switch (60) is integrated in the arm (51).