Actuation Device for a Parking Brake

Abstract

The invention relates to an actuation device (1) for a parking brake and is comprised of a parking brake lever (2) swivel-mounted on a bearing block (3) and a blocking device by means of which the parking brake lever (2) can be fixed in place in a swivel position on the bearing block (3). The blocking device has a locking segment (11) that is connected to the bearing block (3) and a pawl (12) mounted on the parking brake lever (2). The bearing block (3) and the locking segment (11) are designed to be one piece and are made of a die-cast part or an injection-molded part.

Claims

1. Actuation device (1) for a parking brake with a parking brake lever (2) swivel-mounted on a bearing block (3) and with a blocking device via which the parking brake lever (2) can be fixed in place in a swivel position on the bearing block (3), wherein the blocking device has a locking segment (11) connected to the bearing block (3) and a pawl (12) mounted on the parking brake lever (2), characterized in that the bearing block (3) and the locking segment (11) are designed to be one piece and are made of a die-cast part or an injection-molded part.

2. Actuation device according to claim 1, characterized in that the die-cast part forming the bearing block (3) and the locking segment (11) is made of magnesium or aluminum.

3. Actuation device according to claim 1, characterized in that the injection-molded part forming the bearing block (3) and the locking segment (11) is made of plastic.

4. Actuation device according to claim 1, characterized in that the width of the locking segment (11) can be freely specified.

5. Actuation device according to claim 1, characterized in that the locking segment (11) has teeth (11a) whose geometries can be specified via the die-cast part or the injection-molded part.

6. Actuation device according to claim 5, characterized in that the locking segment (11) has external teeth on a convex surface.

7. Actuation device according to claim 5, characterized in that the locking segment (11) has internal teeth on a concave surface.

8. Actuation device according to claim 1, characterized in that the pawl (12) is made of a metallic material.

9. Actuation device according to claim 8, characterized in that the pawl (12) is made of aluminum or magnesium.

10. Actuation device according to claim 1, characterized in that the pawl (12) is made of plastic.

11. Actuation device according to claim 1, characterized in that the pawl (12) is moved towards the locking segment (11) or away from it with linear positioning movements.

12. Actuation device according to claim 11, characterized in that the pawl (12) has several ratchet teeth (12a).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The invention will be illustrated with the aid of the drawings below. The following are shown in the figures:

[0023] FIG. 1: Example of the actuation device for a parking brake as per the invention.

[0024] FIG. 2: Sectional view of the locking segment of the actuation device in accordance with FIG. 1.

[0025] FIG. 3: Alternative embodiment of the locking segment for the actuation device in accordance with FIG. 1.

[0026] FIG. 4: Individual diagram of a pawl for the actuation device in accordance with FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] FIG. 1 schematically shows an example of the actuation device 1 as per the invention for a parking brake of a motor vehicle.

[0028] The actuation device 1 is comprised of a parking brake lever 2 and a bearing block 3. The parking brake lever 2 is swivel-mounted around a horizontal axis on the bearing block 3. The bearing block 3 is comprised of two flanks 3a with identical designs and a base piece 3b. The identically designed flanks 3a run in parallel and at a distance to one another. The flanks 3a project at a right angle from the base piece 3b in each case and are designed to be one piece with it. Each flank 3a has a hole 4 to form the swivel bearing. The identically designed holes 4 are opposite one another. Furthermore, the parking brake lever 2 has a tube-shaped receptacle 5 to form the swivel bearing. The parking brake lever 2 is swivel-mounted on the bearing block 3 via a shaft 6 or the like that is routed through the holes 4 on the bearing block 3 and the tube-shaped receptacle 5.

[0029] The respective swivel position of the parking brake lever 2 is transferred via a pull rod or the like, which is not shown, to the parking brake, likewise not shown, of the motor vehicle in which the actuation device 1 is installed.

[0030] The parking brake lever 2 has a rod-shaped base body 7 that is designed to be one piece with the tube-shaped receptacle 5 or that is at least connected to it in a fixed way. The base body 7 is formed by a laterally open profile in this case. An actuation rod 8 is mounted in the elongated front area of the base body 7 that projects over the bearing block 3. A button 9 projecting over the front end of the base body 7 is mounted on the front end of the actuation rod 8. The actuation rod 8 can be moved in an axial direction by actuating the button 9 against the spring force of a spring 10 that is mounted in the base body 7 and that surrounds the actuation rod 8. As soon as the button 9 is released, the actuation rod 8 is moved back again into its starting position by the spring force of the spring 10.

[0031] The parking brake lever 2, in particular its base body 7, is covered when fully assembled with a lining, not shown, whose front portion forms a handle; an operator grips the parking brake lever 2 with this to swivel it.

[0032] A blocking device is provided to fix the parking brake lever 2 in place in a specific swivel position. The blocking device is comprised of a locking segment 11 on the bearing block 3 and a pawl 12 on the parking brake lever 2.

[0033] FIGS. 2 and 3 show two variants of a locking segment 11 in an individual diagram. FIG. 4 shows the pawl 12 in an individual diagram.

[0034] The pawl 12 is comprised in the instant case of a plastic injection-molded part. The pawl 12 has several ratchet teeth 12a (FIG. 4a) on its front edge that is turned towards the locking segment 11. The pawl 12 is mounted so as to be movable in the axial direction in a receptacle 13 that is a component of the parking brake lever 2 and that is laterally connected to its base body 7. The direction of motion of the pawl 12 runs in parallel with the direction of motion of the actuation rod 8. The pawl 12 is connected to the actuation rod 8 via a coupling element that is not separately shown. When the button 9 is pressed by an operator, the pawl 12 is inserted into the receptacle 5 because of the excursion of the actuation rod 8 caused by that. If the operator releases the button 9, the pawl 12 is pushed out of the receptacle 5 again via the return movement of the actuation rod 8.

[0035] The locking segment 11 has a one-piece design with the bearing block 3 as per the invention. The bearing block 3 with the locking segment 11 is comprised of one die-cast part that is made of magnesium in this case. In general, the die-cast part can also be made of a different metallic material such as aluminum. Furthermore, the bearing block 3 with the locking segment 11 could also be made of a plastic injection-molded part.

[0036] The locking segment 11 is arranged on the inside surface of a flank 3a of the bearing block 3 and, in fact, to the effect that the locking segment 11 is opposite the pawl 12 at a short distance.

[0037] As seen in FIG. 1 and the accompanying section view of FIG. 2, the locking segment 11 has inner teeth on a concave, circular-cylindrical surface on the inside surface of the locking segment 11 that is turned towards the pawl 12. The external surface of the locking segment 11 is also formed by a section of a circular-cylindrical surface. The toothing has a regular arrangement of identically designed teeth 11a that extend over the entire length of the locking segment 11.

[0038] FIG. 3 shows an alternative design form of the locking segment 11. External teeth are provided there, meaning that the teeth 11a are located on a convex surface of the locking segment 11 here.

[0039] In general, the geometries of the teeth 11a of the locking segment 11 can be precisely specified with the manufacturing process of the die-cast part, meaning that rework of the teeth 11a is not required.

[0040] The overall geometry of the locking segment 11 can also be precisely specified in the manufacturing process of the die-cast part; the geometry of the locking segment 11 can be freely chosen in broad areas. In particular, as FIG. 1 shows, the width of the locking segment 11 can be chosen to be substantially greater than the width of the pawl 12; an especially good hold of the pawl 12 on the locking segment 11 is ensured because of that.

[0041] The blocking device of the actuation device 1 in accordance with FIG. 1 operates in such a way that when the button 9 is not actuated, the actuation rod 8 exerts a force via the spring 10 on the pawl 12 so that it is pushed out of the receptacle 5 and pressed with contact pressure against the locking segment 11, so the ratchet teeth 12a of the pawl 12 engage with the teeth 11a of a partial area of the toothing of the locking segment 11. The parking brake lever 2 is fixed in place in a swivel position on the bearing block 3 because of that. It is important, when the pawl 12 is pressed against the locking segment 11, that the pawl 12 is guided with a linear movement against the locking segment 11. It is therefore possible to equip the pawl 12 with several ratchet teeth 12a; the hold of the pawl 12 on the locking segment 11 is improved because of that.

[0042] If the blocking device is to be released so that the parking brake lever 2 can be put into a different swivel position, an operator presses the button 9. The movement of the actuation rod 8 caused by that is converted via the coupling element into a movement of the pawl 12 to the effect that this pawl 12 is moved into the receptacle 5 and the ratchet teeth 12a of the pawl 12 are consequently no longer engaged with the teeth 11a of the locking segment 11. The operator can then swivel the parking brake lever 2 into the new desired swivel position. After that, the operator releases the button 9. The actuation rod 8 is moved into its starting position by the spring force of the spring 10 because of that, causing the pawl 12 to be moved against the locking segment 11 so that the ratchet teeth 12a of the pawl 12 are pressed with contact pressure against the teeth 11a of a new partial area of the toothing. The new swivel position of the parking brake lever 2 is thereby fixed in place.

[0043] The parking brake can be released by putting the parking brake lever 2 into a swivel position constituting a neutral position. The parking brake can be tightened, meaning actuated, by swiveling the parking brake lever 2 into a swivel position that is preferably above the neutral position.

LIST OF REFERENCE NUMERALS

[0044] (1) Actuation device [0045] (2) Parking brake lever [0046] (3) Bearing block [0047] (3a) Flank [0048] (3b) Base piece [0049] (4) Hole [0050] (5) Receptacle [0051] (6) Shaft [0052] (7) Base body [0053] (8) Actuation rod [0054] (9) Button [0055] (10) Spring [0056] (11) Locking segment [0057] (11a) Teeth [0058] (12) Pawl [0059] (12a) Ratchet teeth [0060] (13) Receptacle