HYDRAULIC ACTUATOR FOR DUAL BRAKING SYSTEM

• US 3,789,962 A
• Filed: 05/25/1972
• Issued: 02/05/1974
• Est. Priority Date: 05/25/1972
• Status: Expired due to Term

• Current Assignee: Emmanuel Frangiudakis
• Original Assignee: Emmanuel Frangiudakis
• Inventors: Frangiudakis, Emmanuel
• Primary Examiner(s): Halvosa, George E. A.
• Application Number:
  US05/256,877
• Time in Patent Office: 621 Days
• Field of Search: 188/345,16P,364,361,362,363 60/54.6M 92/61
• US Class Current: 188/345
• CPC Class Codes: B60T 13/12 the fluid being liquid
• CPC Class Codes: F16D 65/22 adapted for pressing members apart , e.g. for drum brakes

Abstract

An actuating device is provided for use particularly with braking systems especially for automobiles, trucks and the like. The hydraulic actuator includes a pair of telescopic tubular cylinders having a common movable piston valve mounted for limited reciprocation therebetween. Each cylinder is connected to a separate hydraulic circuit either or both of which when pressurized will cause the cylinders to spread apart so as to actuate the braking mechanism. The device will actuate irrespective of failure of one of the hydraulic lines.

Claims

1. An actuator for use in a dual hydraulic braking system having movable brake members, comprising a. a pair of tubular cylinders telescopically and slidably connected to one another, the outside diameter of one cylinder substantially corresponding to the inside diameter of the other cylinder, said one cylinder being telescoped within the other cylinder, b. the inner ends of said cylinders being open and the outer ends being closed, c. an imperforate piston mounted for limited reciprocation within both of said cylinders, d. said piston being formed with a reduced portion at the end within the one smaller diameter cylinder and an enlarged annularly shouldered portion at the opposite end within said other larger diameter cylinder.

2. An actuator according to claim 1 including a bracket rigidly mounting one of said cylinders.

3. An actuator according to claim 1 in combination with a pair of pivotally mounted brake shoes drivingly connected to opposite ends of said cylinders.

4. An actuator according to claim 3 including adjustable screw means connecting the outer end of each cylinder to each of said shoes, said screw means including a threaded coupling mounted coaxially at the outer end of each cylinder for movement along the axis of said cylinders and a nut rotatably connected to each of said cylinders and threadably engaging each of said couplings for axial adjustment thereof.