EP1827936A1

EP1827936A1 - Actuator for operation of a mechanical brake on a motor vehicle

Info

Publication number: EP1827936A1
Application number: EP05819806A
Authority: EP
Inventors: Sandor PALVÖLGYI; Martin PALVÖLGYI
Original assignee: Magna Systemtechnik Gmbh&Co oHG
Current assignee: Magna Systemtechnik Gmbh&Co oHG
Priority date: 2004-12-20
Filing date: 2005-12-20
Publication date: 2007-09-05
Also published as: AT8521U1; WO2006066298A1

Abstract

The invention relates to an actuator for operation of a mechanical brake on a motor vehicle, with two tensile forces acting in opposing directions on the input element (10) thereof which pivots about an axis (11), permitting a suitable force path and a friction-free force equalisation with small assembly size. The above is achieved, whereby a first (15) and a second (16) body of a four-bar linkage are mounted on diametrically opposed points (13, 14) of the input element (10), both bodies (15,16) run essentially parallel and are connected to each other by means of a third body (19). Two tensile elements (6,7) are connected with the actuator-side ends thereof to a body (15,16) of the four bar linkage.

Description

ACTUATOR FOR ACTUATING A MECHANICAL BRAKE OF A MOTOR VEHICLE

The invention relates to an actuator for the actuation of a mechanical brake of a motor vehicle, consisting of an input element pivotable about an axis, on which on the one hand a force source acts and which on the other hand exerts tensile forces acting in two different directions, wherein a compensation takes place between the two tensile forces , In particular, a so-called handbrake is intended, even if it is not operated by means of a hand lever, which acts on the two wheels of an axle; therefore the compensation of the tensile forces.

From WO 03/008248 Al _5, in particular from its FIG. 8, an actuator is known, on whose input element two diametrically opposite rollers are mounted, over which a tension element is guided in an S-shape. One end of the tension element leads to the brake of one wheel, the other to that of the other. To tighten the brake, the input member is twisted, so that a tensile force is exerted in both directions. The rollers allow the force to be balanced without causing the tension element to rub off. However, the tension element, usually a relatively stiff wire rope, when passing over the rollers exposed to a bending, which also wears it. To minimize this, the radius of the rollers is as large as possible, which increases the space requirement of the act.

Functionally, the known solution has two disadvantages: First, the brake drops when the rope tears on both wheels, ie completely. Secondly, when the brake is applied, the lever arm changes in such a way that, at the beginning, when the brake is not yet engaged, it is the smallest and at the end, when the greatest force is needed, it is the smallest. It should be the other way around. Then also the continuous load of the tension element would be the smallest when the handbrake is activated.

It is therefore an object of the invention to provide an actuator which avoids the mentioned disadvantages. With small installation dimensions, it should allow for an adapted force curve and a smooth force compensation, without the entire brake failing in case of rope breakage.

According to the invention this is achieved in that at diametrically opposite points of the input element, a first and a second member of a four-bar linkage is mounted, which two members are substantially parallel and coupled by a third member, and that two tension elements with their actuator side Ends are connected to a link of the four-bar linkage. The latter also ensures the function of at least one brake even when the rope breaks. The four-bar linkage allows friction and wear-free force compensation in the smallest space. The essentially parallel links betray a wattage variation which is varied beyond recognition. As a result, the course of the transmission ratio also meets the specific requirements: When the input element is rotated, the normal distance of the tension element from the pivot axis of the input element is ever smaller, which corresponds to a progressively increasing ratio.

The four-bar linkage itself can be made externally very different while maintaining the essence of the invention and all the advantages. In a first embodiment, the first and second members are connected at second points to the third member, and at third points, the tension members are connected (claims 2, 2, 3, 4, 5). There are two variants of this:

In a first variant of the second embodiment, the first and the second member are two-armed levers, wherein the second points are at the side of the first points facing away from the third points and the third element connecting the second points runs substantially diametrically relative to the pivot axis of the input element ( Claim 3, Fig. 2,3). Thus, the three members in plan view form a "Z".

In a second variant of the second embodiment, the first and second links are one-armed levers, the second points being respectively between the first and third points, and the third link connecting the second points being substantially diametrical with respect to the pivot axis of the input element , (Claim 4, Fig. 4.5) Thus, the three members form an "H".

In a second embodiment, the first and second members are one-arm levers extending in opposite directions from the first points in which they are supported on the input member and the other end being hingedly connected at second points to the third member and the third member has arms extending in opposite directions across the line connecting the second points, at the ends of which Tension elements are connected in third points. (Claim 5, Fig. 6,7). To further protect the tension element, the tension elements in the third points are hinged (claim 6).

In the following the invention will be described and explained with reference to figures. They show:

1 shows a schematic sketch of a vehicle axle with the actuator according to the invention,

2: a first embodiment in a first variant, relaxed, FIG. 3: as in FIG. 2, stretched,

4 shows a first embodiment in a second variant, relaxed,

FIG. 5: as in FIG. 4, stretched,

FIG. 6: a second embodiment, relaxed,

- Fig. 7: as shown in FIG. 6, stretched.

In Fig.l the axis of a motor vehicle is indicated and denoted by 1, her left wheel with 2 and her right wheel with 3. From an actuator 4 according to the invention with a power source 5 lead wire ropes 6,7 to brake levers 8, 9, with which not shown wheel brakes are actuated.

Fig. 2 shows the actuator of the wheel brakes in an untensioned position, that is, the wheel brakes are released. In an actuator carrier, not shown, an input element 10 is rotatably mounted about an axis 11. The input element 10 is here a circular disk, on whose periphery a power source, here an electric geared motor via a gear 12, engages. At the input element 10 at first points 13, 14 each have a first member 15, 16 articulated. What is here and hereinafter referred to as a point, for example, a pin that makes a hinged connection, or the like. Second points 17, 18 are connected by a third link 19.

The second points 17, 18 as well as the first points 13, 14 are diametrically opposite each other with respect to the axis 11. At third points 21, 22 of the first member 15 and second member 16, the traction means 6, 7 leading to the wheel brakes engage. The traction means 6, 7 are wire ropes which are partially surrounded by a shell and thus form a Bowden cable. The first points 13, 14 are arranged between the second points 17, 18 and the third points 21, 22 and on a slightly smaller radius. The first and second links thus each form a two-armed lever, with the connecting lines of the second points 17, 18 and the third points 21, 22 being approximately parallel. The third member 19 forms with the first member 15 and the second member 16 a "Z".

The cocked position of Fig. 3 is achieved by the gear 12, the input member 10 rotates through a right angle in the clockwise direction. In this position, the reference numerals are provided with an apostrophe. The stroke generated by the third points 21, 22 up to the position 21 ', 22' is designated by 23. During this movement, the distance 26 of the traction means 7 reduces to the radial distance 26 '. As a result, the closer you get to the tensioned position, the higher the force transmission.

The variant of Fig. 4 differs from the previous one by another embodiment of the four-bar linkage formed by the three links and in that a hand lever 32 is provided as the power source, which acts directly on the input member here. Furthermore, the previous variant of the corresponding parts carry the 20 increased reference numerals of Figure 2. In the first points 33, 34 of the input element 30, in each case a first member 35 and a second member 36 are pivotally mounted again. These members 35, 36 form one-armed lever, the second points 37, 38 by a third Link 39 are connected. At third points 41, 42 again the traction means 6, 7 are connected. The second points 37, 38 are located between the first points 33, 34 and the third points 41, 42.

The cocked position of Fig. 5 is achieved by tilting the hand lever 32 by a right angle in the counterclockwise direction. In this position, the reference numerals are again provided with an apostrophe. The case covered by the third points 41, 42 stroke is denoted by 43, the radial distance of the traction means 7 with 46 or 46 '.

Fig. 6 shows a second embodiment of the actuator according to the invention. Corresponding reference numerals are increased by 40. In first points 53, 54 of the input element 50, a first member 55 and a second member 56 is pivotally mounted again. These form one-armed lever at the other end second points 57, 58 are connected by a third member 59. Here it is this third member 59 which forms approximately transverse to the line connecting the two second points 57, 58 extending arms 64, 65, at the outer ends of the third points 61, 62 are formed. At this again attack the traction means 6, 7.

In Fig. 7 corresponding parts and points are again provided with an apostrophe. The radial distance of the traction means 7 'is denoted by 66' and the distance traveled in the transition from the position of Figure 6 in the position of Figure 7 with 63 '.

6, the operation of all described embodiments and variants is particularly clear. When the tensile force on both traction means 6, 7 is equal, the third member is rotated upon pivoting of the hand lever 52 about a pole which is connected to the axis 51 of the input member 50 coincides, although the third member 59 is not stored there at all.

However, if the force exerted by the traction means 7 is greater than that exerted by the traction means 6, then the third point 62 on which the traction means 7 engages will want to move upwards. Since the third member 59 is the coupling member of the four-bar joint formed by the first member 55 and the second member 56, and because the first member 55 and the second member 56 are approximately parallel, the third member 59 can change without its direction, ie without turning, move upwards and so pass on the force exerted by the second pulling means 7 force on the first traction means 6. In this way, a force balance and thus a path compensation takes place.

Claims

Patent claims

1. Actuator for actuating a mechanical brake of a motor vehicle, comprising an input element pivotable about an axis, on the one hand acts on a power source and on the other hand exerts tensile forces acting in two different directions, wherein between the two tensile forces compensation takes place, characterized that at diametrically opposite points (13, 14; 33, 34; 53, 54) of the input element (10; 30; 50) a first (15; 35; 55) and a second (16; 36; 56) member of a Which are coupled to each other substantially parallel and by a third member (19; 39; 59), and that two tension elements (6,7) with their actuator-side ends connected to a link (15, 16, 35, 36, 59) of the four-bar linkage.

2. Actuator according to claim 1, characterized in that the first (15; 35) and the second (16; 36) member at second points (17,18; 37,38) are connected to the third member (19; 39) and that at third points (21, 22; 41, 42) the tension elements (6, 7) are connected. (Figures 2,3, 4,5) 3. Actuator according to claim 2, characterized in that the first (15) and the second member (16) are two-armed lever, wherein the second points (17,18) at the third points (21,22) facing away from the first Are points (13,14) and the second member (17,18) connecting third member (19) with respect to the pivot axis (11) of the input member (10) is substantially diametrically. (Fig. 2,

3)

Actuator according to Claim 2, characterized in that the first (35) and the second member (36) are one-armed levers, the second points (37, 38) being respectively between the first points (33, 34) and the third (36). 41, 42) points, and the third member (39) connecting the second points (37, 38) extends substantially diametrically relative to the pivot axis (31) of the input member (30). (Fig. 4,5)

Actuator according to Claim 1, characterized in that the first (55) and second links (56) are one-armed levers extending from the first points (53, 54) in which they are mounted on the input element (50). extend in opposite directions and the other end is pivotally connected at second points (57,58) with the third member (59) and that the third member (59) in opposite directions approximately parallel to the connecting line of the first (53,54 ) and second points (57,58) of the first (54) and second (55) member extending arms (64,65), at the ends of the tension elements (6,7) in third points (61,62) are connected. (Fig. 6,7).

6. Actuator according to claim 1, characterized in that the tension elements (6, 7) are articulated in the third points (21, 22, 41, 42; 61, 62).