Search

JP-7854785-B2 - Drum brake system

JP7854785B2JP 7854785 B2JP7854785 B2JP 7854785B2JP-7854785-B2

Inventors

  • ジョ チ フーン

Assignees

  • ヒュンダイ・モービス・カンパニー・リミテッド

Dates

Publication Date
20260507
Application Date
20210623
Priority Date
20200623

Claims (13)

  1. Housing and A main braking unit is provided on one side of the housing and is driven by hydraulic pressure during main braking to pressurize the shoe, A parking braking unit is provided on the other side of the housing and is driven by the electric force of the actuator to pressurize the shoe during parking braking, A first fastening member for fixing the housing to one surface of the back plate, The back plate includes a second fastening member that secures the actuator to the housing on the other side of the back plate, The housing includes a housing portion , a piston housing portion, and a rod housing portion. The aforementioned housing portion is The main body portion in which the piston housing portion and the rod housing portion are formed, A first fixing portion is formed on the main body portion and fixed to the back plate by the first fastening member, A through extension is formed at the end of the main body portion, passes through a through hole formed in the back plate , and is positioned on the other side of the back plate, to which the actuator is connected , The second fastening member is fastened to the second fixing portion, A drum brake device characterized by including the following:
  2. The piston housing is formed to be hollow on one side of the housing, and the main braking section is provided there. The rod housing portion is formed to be hollow on the other side of the housing portion, the parking brake portion is provided, and is positioned away from the piston housing portion from the rotation center of the shoe. The drum brake device according to feature 1.
  3. The first fixing part is, A left-side fixing portion is formed on the left side of the main body portion and is fixed to the back plate by the first fastening member, The main body portion includes a right-side fixing portion formed on the right side and fixed to the back plate by the first fastening member, The drum brake device according to claim 1, characterized in that the through extension is arranged between the left fixing portion and the right fixing portion.
  4. The piston housing portion is The cylinder section in which the main braking unit is housed, It includes a hydraulic flow path that extends from both sides of the through extension to the cylinder and forms a flow path for supplying fluid to the inside of the cylinder, The drum brake device according to claim 1, characterized in that the second fixing portion is arranged in the lateral intermediate portion of the through extension portion at a distance from the hydraulic flow path portion.
  5. The present invention further includes a rotation prevention assembly that restrains the rotation of the actuator around the second fastening member by fitting and assembling the housing and the actuator, The aforementioned rod housing section is The rod cylinder section in which the parking brake unit is housed, It includes a drive shaft housing that extends from the through extension to the rod cylinder and into which the output shaft of the actuator is retracted and connected to the parking brake section, The second fixing portion is arranged on one side of the drive shaft housing portion, spaced apart from the first fixing portion. The drum brake device according to claim 4, characterized in that the anti-rotation assembly is formed on the opposite side from the second fixing portion with reference to the central portion of the drive shaft housing portion.
  6. The aforementioned anti-rotation assembly part is A rotation prevention groove is formed in communication with the peripheral edge of the drive shaft housing and recessed in the direction extending from the drive shaft housing, The drum brake device according to claim 5, characterized in that it includes a rotation-preventing projection formed protruding from the actuator and fitted into the rotation-preventing groove.
  7. The aforementioned housing portion is The drum brake device according to claim 1, further comprising a foreign matter inflow prevention portion which is coupled to the side of the main body portion where the piston housing portion and the rod housing portion are located, and covers the peripheral edge of the piston housing portion and the peripheral edge of the rod housing portion.
  8. The aforementioned foreign matter inflow prevention unit is, A connecting portion is disposed between the opening of the piston housing and the opening of the rod housing, A piston sealing portion having a ring shape corresponding to the peripheral edge of the piston housing portion, formed continuously on one side of the connecting portion, and whose inner end is connected to the main braking portion, A rod sealing portion having a ring shape corresponding to the peripheral edge of the rod housing portion, formed continuously on the other side of the connecting portion, and whose inner end is connected to the parking brake portion, The drum brake device according to claim 7, characterized in that it includes a main body fixing portion formed on the connecting portion and fixed to the main body portion.
  9. The piston housing and the rod housing are located on the same radial extension line with respect to the rotation center of the back plate. The drum brake device according to claim 2, characterized in that the actuator is located on the same radial extension line as the chassis supporting the central part of the back plate and is positioned alongside the center of rotation of the back plate.
  10. The main braking unit is, A piston is positioned at the end of the housing and moves to the outside of the housing by hydraulic pressure to pressurize the shoe, The drum brake device according to claim 1, further comprising an elastic member disposed inside the housing to reduce the impact force acting on the piston that returns to the inside of the housing.
  11. The aforementioned parking brake unit is, A gear section is disposed inside the housing and rotates in conjunction with the actuator, The drum brake device according to claim 1, characterized in that it includes a rod portion connected to the gear portion, which moves to the outside of the housing in conjunction with the gear portion and pressurizes the shoe.
  12. The drum brake device according to claim 1, further comprising a rotation prevention assembly portion positioned at a distance from the second fastening member, which restrains the rotation of the actuator around the second fastening member through a fitting assembly between the housing and the actuator.
  13. The aforementioned anti-rotation assembly part is The housing and the actuator have a recessed anti-rotation groove portion formed on one side, The drum brake device according to claim 12, characterized in that it includes the housing and a rotation-preventing projection formed to protrude from the other side of the actuator and fitted into the rotation-preventing groove.

Description

This invention relates to a drum brake device, and more particularly, to a drum brake device that generates braking force by friction with a drum that rotates together with a wheel. Generally, drum brakes are devices that generate braking force by friction between a drum that rotates with the wheel and the drum. They either use hydraulics (primary braking) or a cable connected to the parking brake lever to create friction between a shoe with friction material attached and the drum (parking braking) to obtain braking force. Conventional drum brakes consist of a drum, a pair of shoes positioned on a backplate facing the inner surface of the drum and fitted with friction material on their outer circumference, and a main braking wheel cylinder that transmits braking hydraulic pressure to move the shoes outward. The parking brake lever on the drum brake has one end axially connected to the shoes and the other end connected via a cable to a parking brake lever located next to the driver's seat. Pulling the parking brake lever mechanically applies the parking brake. The background art of this invention is disclosed in Korean Patent Publication No. 2018-0047519 (published May 10, 2018; Title of Invention: Drum Brake for Vehicles). This is a front perspective view showing the installed state of a drum brake device according to one embodiment of the present invention.This is a rear perspective view showing the installed state of a drum brake device according to one embodiment of the present invention.This is a cross-sectional view of a main part of a drum brake device according to one embodiment of the present invention.This is a front perspective view showing the housing of a drum brake device according to one embodiment of the present invention.This is a rear perspective view showing the housing of a drum brake device according to one embodiment of the present invention.This is an assembly drawing of the main parts of a drum brake device according to one embodiment of the present invention.This is a perspective view showing a foreign matter inflow prevention section of a drum brake device according to one embodiment of the present invention.This is a cross-sectional view taken along line A-A' in Figure 7.This is a conceptual diagram illustrating the tolerances resulting from the arrangement of the main braking unit and the parking braking unit of a drum brake device according to one embodiment of the present invention.This is a cross-sectional view taken along the line B-B' in Figure 1. The following describes embodiments of the drum brake device according to the present invention with reference to the attached drawings. In this process, the thickness of lines and the size of components shown in the drawings may be exaggerated for clarity and convenience of explanation. Furthermore, the terms described later are defined considering the function of the present invention, and these may vary depending on the intent or convention of the user or operator. Therefore, the definitions of these terms must be based on the content throughout this specification. Figure 1 is a front perspective view showing the installed state of a drum brake device according to one embodiment of the present invention; Figure 2 is a rear perspective view showing the installed state of a drum brake device according to one embodiment of the present invention; and Figure 3 is a cross-sectional view of the main part of a drum brake device according to one embodiment of the present invention. Referring to Figures 1 to 3, a drum brake device 1 according to one embodiment of the present invention includes a housing 100, a main braking unit 200, a parking braking unit 300, a first fastening member 410, a second fastening member 420, and an anti-rotation assembly unit 430. The housing 100 is positioned between a pair of left and right brake shoes 2. The main braking unit 200 is located on one side of the housing 100 and is driven hydraulically during main braking to pressurize the shoes 2. The parking braking unit 300 is located on the other side of the housing 100 and is driven electrically during parking braking to pressurize the shoes 2. Both ends of the main braking unit 200 are positioned to engage with one side of the shoe 2, and the parking braking unit 300 is positioned at a set distance from the main braking unit 200 to engage with the other side of the shoe 2. The first fastening member 410 secures the housing 100 to a set position on one surface of the back plate 5. The first fastening member 410 fastens to the housing 100 by passing through the back plate 5, thereby binding the back plate 5 and the housing 100 together. The second fastening member 420 penetrates the back plate 5 and secures the actuator 310 to the end of the housing 100, which is located on the other side of the back plate 5. The second fastening member 420 secures the actuator 310 to the housing 100 on the other side of the back plate 5. By fastening the second fastening me