Actuator and drum brake including the same
AssigneeHl Mando Corporation
InventorYoodon Jung
Life of this patent
Estimating the term…
Abstract
An actuator used in a drum brake according to the present embodiment may include a case with a space therein, a shaft rotated by a motor and having a worm gear formed thereon, a wheel gear engaged with the worm gear, a spindle bolt passing through and coupled to the wheel gear and including a head and a column of which an outer circumferential surface is provided with a thread, a spindle nut fastened to the thread of the spindle bolt, a first piston of which one side is in contact with the spindle nut and the other side is in contact with the first brake shoe, a second piston of which one side is in contact with the head of the spindle bolt and the other side is in contact with the second brake shoe, and an O-ring disposed between the spindle nut and the wheel gear.
Claims20
An actuator used in a drum brake, comprising:
- a case with a space therein;
- a shaft rotated by a motor and having a worm gear formed thereon;
- a wheel gear engaged with the worm gear;
- a spindle bolt passing through and coupled to the wheel gear and including a head and a column of which an outer circumferential surface is provided with a thread;
- a spindle nut fastened to the thread of the spindle bolt;
- a first piston of which one side is in contact with the spindle nut and the other side is in contact with the first brake shoe;
- a second piston of which one side is in contact with the head of the spindle bolt and the other side is in contact with the second brake shoe;
- and
- an O-ring disposed between the spindle nut and the wheel gear.
A drum brake comprising:
- a motor;
- a case with a space therein;
- a wheel gear rotated in the case using a driving force provided by the motor;
- a spindle bolt including a head and a column of which an outer circumferential surface is fitted into the wheel gear and provided with a thread;
- a spindle nut fastened to the thread;
- a first piston disposed in front of the spindle nut so that an end portion of the column is inserted into the first piston;
- a second piston into which the head of the spindle bolt is fitted;
- an O-ring disposed between the spindle nut and the wheel gear;
- a first brake shoe which comes into contact with the first piston;
- a second brake shoe which comes into contact with the second piston;
- a detector configured to detect a current applied to the motor;
- and
- a controller configured to compare a normal current pattern corresponding to a pattern of a current applied to the motor in a normal state with a pattern of a current detected by the detector.
Dependencies are inferred from the claim text.