Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
  • B66B5/00—Applications of checking, fault-correcting, or safety devices in elevators
  • B66B5/02—Applications of checking, fault-correcting, or safety devices in elevators responsive to abnormal operating conditions
  • B66B5/16—Braking or catch devices operating between cars, cages, or skips and fixed guide elements or surfaces in hoistway or well

Definitions

• This invention relates to elevators, in particular, elevator brakes and safeties.
• the brake which is electromechanically operated, is located in the machining room, where it is attached to the drive.
• the braking force is limited by the traction between the cables and the drive.
• the drive may "slip traction", reducing the braking force significantly.
• the elevator safety a separate stopping device, is located on the elevator car.
• a safety rapidly engages the elevator rail to stop the elevator car.
• the safeties are usually progressive; that is, they progressively reach a maximum tolerable acceleration rate.
• Safety operation is typically controlled by an elevator governor, which, generally speaking, is a mechanical device that is connected to the elevator car and which, upon sensing elevator car overspeed, provides a mechanical pull (actuation) to the safety, causing it to engage the rail. Disclosure of the Invention
• An object of the present invention is have both the brake and safety on the car.
• a brake e.g. caliper brake
• the brake is mechanically biased to normally freely engage the rail, but the bias is overcome or prevented by a brake control when braking is not needed. If overspeed is detected, however, the operative connection between the brake control and the brake is interupted, allowing the mechanical bias to apply the brake.
• the bias is overcome by a hydraulic actuator operated by energizing a solenoid to operate a master cylinder.
• the line connecting the master cylinder and Jthe actuator is vented by another valve when overspeed is detected, thereby eliminating the need to retract the master cylinder to apply the brake.
• Fig. 1 is a function block diagram of an elevator according to the invention.
• Fig. 2 is a function block diagram of a brake control system according to the invention.
• Fig. 3 is plain view of a brake and a rail that may be used in an elevator embodying the invention. Best Mode for Carrying Out the Invention
• a car 10 In the elevator in Fig. 1, there is a car 10, counterweight (CW) 12, motor 14, motor control (MCNTRL) 16 and two guide rails 18.
• CW counterweight
• MCNTRL motor control
• PPT motor control
• the governor in this application is connected to the velocity transducer, which, for illustrative purposes, senses car motion relative to a tape 20a to provide car velocity output signals. Position and velocity measurement in that manner is well known.
• the governor When the velocity or acceleration or both exceeds predetermined levels, the governor provides an ES signal to bring the car to an emergency stop.
• the ES signal is supplied to a brake control 28, also on top of the car.
• the brake control 28 which is also connected to the motor control 16 by a traveling cable 30, controls operation of two brakes 32 and they are also on top of the car. These brakes engage the rails, but are maintained in disengagement by the brake control 28 in response to a brake release (BR) signal provided from the motor control except when the car is stopping or is parked, conditions when braking is needed.
• BR brake release
• Fig. 2 shows that the brake control 28 contains an oil tank 29 containing a reservoir of hydraulic fluid, and a master cylinder (MC) 31 operated by a solenoid (SOL) 33 which receives the BR signal from the motor control 16.
• the solenoid has a plunger 33a that controls the position of the master cylinder.
• the master cylinder provides fluid through two lines 31a to the brakes, each of which contains brake shoes 32a that are squeezed against the guide rails by means of the caliper 32b, as shown in Fig 3.
• Each brake contains a spring 40 which expands outwardly so as to force the pads against the rail, an action by which the brake is applied.
• Each brake also contains two separate brake actuators or cylinders (BC) 32c on opposite sides of the spring.
• BC brake actuators or cylinders
• the governor senses that from the transducer and provides the ES signal to the brake control.
• another solenoid 50 receives the signal and operates a release valve (RV) 52, and this "vents" the master cylinder to the tank, (i.e., releases the pressure in the lines 31a) .
• the ES signal thus interupts the operative connection between the master cylinder and the brake cylinders. Consequently, all pressure from brake cylinders 32c is eliminated, allowing the caliper to ciose immediately by operation of the spring, even if the BR signal is still applied.
• a hydraulic pump may be used, but with a similar control that positively releases the brake cylinders. That is, even if a configuration like that is utilized, an electromechanical valve which is operated independently by the governor should still be employed to positively release the pressure on the brake actuators.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Braking Arrangements (AREA)
• Maintenance And Inspection Apparatuses For Elevators (AREA)
• Elevator Control (AREA)
• Cage And Drive Apparatuses For Elevators (AREA)
• Types And Forms Of Lifts (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=9309894

Family Applications (1)

Country Status (7)

Cited By (1)

Families Citing this family (26)

Citations (4)

Family Cites Families (6)

• 1984
  • 1984-11-23 FR FR8417901A patent/FR2573741B3/fr not_active Expired
• 1985
  • 1985-11-18 WO PCT/US1985/002259 patent/WO1986003184A1/en unknown
  • 1985-11-18 AU AU51965/86A patent/AU568036B2/en not_active Ceased
  • 1985-11-18 JP JP50536285A patent/JPS62500864A/ja active Pending
  • 1985-11-20 CN CN 85109248 patent/CN1007613B/zh not_active Expired
  • 1985-11-20 CA CA000495759A patent/CA1262875A/en not_active Expired
  • 1985-11-22 EP EP85402282A patent/EP0183616A3/en not_active Withdrawn

Patent Citations (4)

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