KR20070002215A - Parking brake device of disk brake - Google Patents

Abstract

A parking brake device of a disk brake is provided to operate a cam stably, and to cut down manufacturing cost by distributing load with relatively rotating an operating shaft and a ramp through a roller. A parking brake device of a disk brake includes a caliper housing(100) having a finger part and a body part(110) and contacting pad plates(2,3) at both sides of a disk(1), a cylinder(114) formed in the body part of the caliper housing, a piston sliding in the cylinder and moving the pad plate to the disk by hydraulic or mechanical thrust, and a cam unit formed in a rear part of the cylinder to convert rotation of a parking brake lever into linear motion of the piston and provided with an operating shaft, a ramp(135) and a roller(137). The roller is formed cylindrically, installed radially to the ramp and tapered longitudinally to arrange the revolution mark of the operating shaft in parallel with the revolution mark of the ramp. Guide grooves(134,136) are formed in the operating shaft and the ramp, and composed of a center groove and side grooves extended at both sides.

Description

Parking brake device of disk brake

1 is a cross-sectional view showing a parking brake apparatus of a conventional disc brake.

2 is a cross-sectional view showing a parking brake apparatus of the disc brake according to the present invention.

3 is a plan view showing a lamp used in the parking brake device of the disc brake according to the present invention.

4 is a cross-sectional view taken along the line IV-IV of FIG. 3 to explain the operation of the cam means used in the parking brake apparatus of the disc brake according to the present invention.

5 is a view illustrating a guide groove of a parking brake apparatus of a disc brake according to another embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

100..Caliper Housing 110..Main Body

112..Piston 125..Push Road

130. Cam means 131. Operating shaft

134, 136..Guide groove 135..Lamp

137..Roller

The present invention relates to a parking brake apparatus for a disc brake, and more particularly, to a cam means of a ball-and-lamp type installed inside a caliper housing.

In general, a brake device is provided on a wheel of an automobile so that a braking force is obtained by operating a brake pedal while driving, and a braking force is generated by an operation of a lever of a parking brake during parking so that a stop state can be maintained.

As an example of the brake device configured as described above, a disk brake provided with a parking brake will be described with reference to FIG. 1. As shown in the drawing, the parking brake lever 6 is rotatably installed on one side of the main body part 5 of the caliper housing 4 in which the pad plates 2 and 3 and the disk 1 are installed. In the parking brake lever 6, the shaft 7 is axially coupled to allow the ramp 8 and the ball 9 to slide, and the shaft 7 is a push rod inside the main body 5. It is configured to be in contact with the piston (11) connected to 10).

Therefore, when the driver pulls the brake handle to park the vehicle, the parking brake lever 6 rotates, and then the shaft 7 which is axially coupled with the lever 6 rotates. Then, the shaft (7) is guided to the ball (9) to move forward along the inclined groove of the lamp (8), push the push rod 10 to operate the piston (11). The piston 11 comes into close contact with the pad plates 2 and 3 on the disk 1 side to generate a braking force.

However, in the structure as described above, the operating load is concentrated on the ball 9 between the shaft 7 and the lamp 8, in particular, the ball 9 at this time is in point contact with the shaft 7 and the lamp 8, respectively. Therefore, it had to be made of high strength material to withstand the load sufficiently. However, the ball 9 of the high-strength material is not only easy to process, but also has a problem that the manufacturing cost is expensive.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a parking brake device for a disk brake that can reduce the manufacturing cost while improving the operability by properly distributing the load concentrated on the ball.

Parking brake apparatus of the disc brake according to the present invention for achieving the above object is a caliper housing consisting of a finger portion and a main body portion to contact the pad plate provided on both sides of the disk to the disc, and a cylinder provided in the body portion of the caliper housing And a piston provided so as to be slidable in the cylinder to move the pad plate to the disc side by thrust generated hydraulically or mechanically, and an operating shaft provided at the rear of the cylinder to convert the rotational movement of the parking brake lever into a linear movement of the piston. And a cam means composed of a lamp and a roller interposed therebetween.

In addition, the roller has a cylindrical shape is installed in the radial direction of the lamp, but the tapered in the longitudinal direction so that the operating shaft and the lamp has a parallel rotational trajectory on the same axis of rotation, the operating shaft and the lamp is a guide groove on the opposite surface Each of them is provided.

In addition, the guide groove is composed of a center groove and side grooves extending to both sides, the side grooves are provided in the shape of a log function, an exponential function, a sin function.

Hereinafter, a parking brake device for a disc brake according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 is a cross-sectional view schematically showing a disc brake provided with a parking brake apparatus according to the present invention.

Referring to the drawings, the disc brake is a disk 1 that rotates like a wheel by using a pair of pad plates (2, 3) to press and brake on both sides, the disc portion (1) between the finger portion ( 105 is provided with a caliper housing 100 formed integrally with the main body 110. Here, the pad plates 2 and 3 are movably coupled to a carrier (not shown) fixed to the vehicle, such that the finger portion 105 and the main body portion 110 move in the center direction from the left and right sides of the disk 1. The pad plates 2 and 3 are brought into close contact with the disc 1.

The main body 110 of the caliper housing 100 is provided with a piston 112 for moving the pad plates 2 and 3 to the disk 1 side, and to the disk 1 side to install the piston 112. An open cylinder 114 is provided therein. In addition, at the rear of the cylinder 114, a cam means 130 for converting the rotational movement of the parking brake lever 9 into the linear movement of the piston 112 is provided. The cam means 130 is composed of an operating shaft 131, a ramp 135, and a roller 137 interposed between the operating shaft 131 and the lamp 135, which will be described later.

The piston 112 is inserted into the cylinder 114 so as to be slidable in the cup 114 and slidably into the cylinder 114, and forms the cylinder 114 and a predetermined pressure chamber 115. Therefore, when hydraulic pressure is provided from the master cylinder (not shown) through the oil inlet hole 113, the pressure chamber 115 expands and moves the piston 112 forward.

The nut adjuster 120 is provided inside the cup 112 of the piston 112. The nut adjuster 120 prevents the pad plates 2 and 3 that are gradually worn away from the disk 1 so as to maintain a constant distance at all times. The nut adjuster 120 is rotatably fitted to the inside of the piston 112 and includes a hollow 122 having a female thread formed on an inner circumferential surface thereof. One end of the push rod 125 in contact with the operating shaft 131 of the cam means 130 is screwed into the hollow 122.

On the other hand, the main body 110, the piston 112 is operated not only by the hydraulic pressure as described above, but also inside of, for example, the rear of the cylinder 114 so that it can be operated mechanically by the rotation of the parking brake lever (9) Cam means 130 is provided. The cam means 130 consists of the operating shaft 131, the ramp 135, and the roller 137 as described above.

As shown in the enlarged view of FIG. 2, the operating shaft 131 has a T-shape and includes a flange portion 132 and a shaft shaft 133. The flange portion 132 is formed in a disk shape, the front surface is in contact with the push rod 125 and the rear surface is in contact with the roller 137. The shaft shaft 133 is axially coupled to the parking brake lever 9 through the main body 110.

The lamp 135 has a hollow disc shape and is inserted into the shaft shaft 133 so as to contact the rear wall of the cylinder 114. The front surface of the lamp 135 is in contact with the roller 137, the rear surface is provided with a projection member 138 for preventing the rotation of the lamp 135 is fixed to the main body 110.

The roller 137 has a cylindrical shape and is provided between the operating shaft 131 and the lamp 135 instead of the conventional ball. Preferably, the roller 137 is at least one, more preferably three rollers 137 at an interval of 120 ° so that the linear movement of the operating shaft 131 can be performed smoothly, the operating shaft 131 and the ramp It is provided between the (135), wherein the roller 137 at the same time and at the same time the disc protector soft protector 139 may be interposed on the shaft 131 and the lamp 135 so that no malfunction occurs. In addition, the roller 137 is placed in the radial direction of the shaft 131, so that the flange portion 132 and the lamp 135 of the operating shaft 131 which is opposed to rotate relative to each other can have a parallel trajectory on the same axis of rotation. Tapered in the longitudinal direction.

In addition, the gap between the operating shaft 131 and the lamp 135 is changed to the rear surface of the opposing flange 132 and the front surface of the lamp 135 while being guided to the roller 137 according to the rotation of the operating shaft 131. Guide grooves 134 and 136 are provided respectively.

3 is a plan view showing a guide groove 136 formed on the front surface of the lamp 135, Figure 4 is a flange portion 132 along the line IV-IV of Figure 3 to explain the operation of the cam means 130 ) Is a cross-sectional view showing a state in which the lamp 135 and the roller 137 is coupled. Here, the guide groove 134 formed in the flange portion 132 is substantially the same as the guide groove 136 formed in the lamp 135, and a detailed description thereof will be omitted.

3 and 4, the guide groove 134 is a center groove 134a on which the roller 137 is stably seated, and a side groove 134b extending inclined at both sides with respect to the center groove 134a. ) Therefore, when the operating shaft 131 rotates according to the rotation of the parking brake lever 9, the flange portion 132 rotates relative to the ramp 135, and the roller 137 is interposed therebetween. The flange portion 132, that is, the operating shaft 131 is to be advanced while being spaced apart.

Referring to this operation in more detail with reference to Figure 4, Figure 4 (a) shows a state before the cam means 130 operates, the flange 132 and the guide groove 134 of the lamp 135 The roller 137 is seated in the center grooves 134a and 136a formed in the 136.

In this state, when the operating shaft 131 is rotated by the parking brake lever 9, as shown in Fig. 4B, the roller 137 is the center groove 134a of the guide grooves 134 and 136. , 136a is moved along the side grooves 134b and 136b which are inclined, and as a result, the gap between the flange portion 132 and the lamp 135 is increased so that the operating shaft 131 is spaced apart from the lamp 135. .

5 illustrates various embodiments of side grooves 134b and 136b formed in the guide grooves 134 and 136. FIG. 5 (a) shows the inclination in the shape of a logarithmic function, and the initial actuation force of the brake is improved by decreasing the output amount sharply at the beginning and gradually decreasing the latter with respect to the input amount. In addition, (b) of FIG. 5 is provided with an inclination in a shape such as an exponential function, which improves the late acting force by gradually increasing the output amount with respect to the input amount. In addition, as shown in (c) of FIG. 5, the inclination is provided in the same shape as the sin function, and the operating amount is improved by smoothing the output amount relative to the input amount.

Next, an operation of the disc brake according to the present invention configured as described above will be described with reference to FIG. 2.

First, when the driver presses the pedal, the hydraulic pressure is generated in the master cylinder. The hydraulic pressure is introduced into the pressure chamber 115 inside the cylinder 114 through the oil inlet hole 113 provided in the caliper housing 100, and the piston 112 is directed toward the disc 1 while the pressure chamber 115 expands. Will be moved. As a result, the pad plate 3 on one side is brought into close contact with the disk 1 first, and the body portion 110 is pushed backward by the continuous pressure expansion, and the finger portion 105 pushes the pad plate 2 on the other side. In close contact with the disk 1, the wheel is braked.

Meanwhile, when the driver pulls the hand brake for parking, the parking cable 21 is pulled to rotate the parking brake lever 9 as shown in FIG. 3. Then, the operating brake 131 axially coupled in the parking brake lever 9 and the main body 110 is rotated, and the roller 137 is then guided 134 of the flange 132 and the lamp 135. 136 moves linearly with the operating shaft 131. As a result, the push rod 125, which is in contact with the flange portion 132 of the shaft 131, is moved to the disk 1 side and the piston 112 is operated to move the pad plates 2 and 3 to the disk 1 side. It comes in close contact.

On the other hand, when the driver releases the hand brake, the push rod 125 is pushed backward by the return spring 116 provided in the cylinder 114, and the operating shaft 131 is returned to its original state, and the torsion spring 119 ), The parking brake lever 9 is correctly returned to the initial position.

As described above in detail, the parking brake device of the disc brake according to the present invention, since the operating shaft and the lamp are rotated relative to each other by the rollers, because the conventional ball system is in line contact, unlike the point contact, the operating load is dispersed and the cam means. The operation is made stable. In addition, since the roller system distributes the concentrated load, it is possible to use a lower cost material than the conventional one, thereby reducing the manufacturing cost.

Claims (6)

A caliper housing composed of a finger portion and a main body portion so as to bring the pad plates provided on both sides of the disk into close contact with the disk, a cylinder provided in the main body portion of the caliper housing, and a cylinder provided to be slidable by hydraulic or mechanically generated thrust. A piston for moving the pad plate to the disc side, and a cam means provided at the rear of the cylinder, the cam shaft comprising an operating shaft, a ramp and a roller interposed therebetween to convert the rotational movement of the parking brake lever into a linear movement of the piston. Parking brake device of the disc brake, characterized in that. The method of claim 1, The roller is formed in a cylindrical shape is installed in the radial direction of the lamp, the operating shaft and the lamp is tapered in the longitudinal direction so as to have side by side rotational trajectory on the same axis of rotation, Parking brake device of the disc brake, characterized in that the operating shaft and the lamp is provided with guide grooves respectively on one surface facing each other. The method of claim 2, The guide groove is a parking brake device of the disc brake, characterized in that consisting of the center groove and side grooves extending to both sides thereof. The method of claim 3, wherein The side brake is a parking brake device of the disc brake, characterized in that provided in the shape of a log function. The method of claim 3, wherein The side groove is a parking brake device of the disc brake, characterized in that provided in the exponential shape. The method of claim 3, wherein The side groove is a parking brake device of the disc brake, characterized in that provided in the sin function shape.

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