SU1416437A1 - Apparatus for diaognosis of brakes of load-handling machines - Google Patents

Abstract

The invention relates to devices for monitoring the braking parameters of hoisting machines. The goal is to increase the amount of information about the technical condition of the brake (t) and to increase the accuracy of measuring the deceleration time. The device contains a force sensor mounted on the tube between the rack and the nut on the outside of T and electrically connected with an intermediate relay, normally closed contacts of which are included in the pulse counter control circuit, and normally open contacts - in the pulse counter control circuit. The input of the latter is included in the stator circuit of the motor drive of the mechanism on which it is installed. At the moment of disconnecting the power from the drive T, the sensor connects a pulse generator through the relay contacts to the input of the pulse counter. At the first contact between the pads and the pulley due to a drop in voltage on the force sensor and an increase in the coil of the relay, the contacts open and disconnect the pulse counter. The recorded number of pulses is proportional to the response time. At the moment of braking, when the pads come into contact with the pulley, the relay contacts are connected to the input of the pulse counter pulse generator. When the brake pulley is completely stopped, the voltage in the stator circuit becomes zero and the relay contacts disconnect the pulse generator from the pulse counter. The recorded number of pulses is proportional to the braking time. 1 il. (O (L 9d 4;: s

Description

This invention relates to a lifting machinery, namely, means for controlling brake parameters.

The aim of the invention is to increase the amount of information about the technical condition of the brake and increase the accuracy of the measurement of the deceleration time.

The drawing shows schematically the proposed device with a shoe brake.

The enable sensor 1 is mounted on the brake drive 2 and is electrically connected to a time meter, which includes a pulse generator 3 and pulse counters 4 and 5 in response time and in time. braking. In the control circuit of the pulse counter, the response time includes normally closed contacts 6 of the intermediate relay 7, and the circuit control pulse counter of the deceleration time includes normally open contacts 8 of the same relay,. which is connected to the power source 9 and the force sensor 10, for example, a carbon sensor mounted on the rod 11 between the rack 12 and the nut 13. The control circuit of the pulse counter for the braking time also includes the contacts 14 of the relay 15, which is included in the stator circuit of the drive motor (the latter is not shown) A brake pulley 17 is located between the pads 16, which is rigidly connected to the shaft of the mechanism drive electric motor.

The device works as follows.

Measurement response time. If there is voltage on the brake actuator 2, the generator 3 pulses are locked. At the moment when the power supply from the brake drive is disconnected, the enable sensor 1 triggers and releases the voltage locking the generator of 3 pulses, and at its output there appear pulses that through the closed contacts 6 of the intermediate relay 7 arrive at the counter 4 pulses in time of running. Pulses are recorded until the start of braking, i.e. until the brake pads 16 come into contact with the brake pulley 17. At this point, a force occurs in t 11, which is sensed by force sensor 10, which causes a decrease in

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the voltage drops across it, and consequently, the voltage increase on the coil of the intermediate relay 7, the contacts of which at the same time open and disconnect the counter 4 pulses at the time of the operation of the generator 3 pulses. In this way, the braking time of the brake is recorded.

Measurement of braking time. At the time of braking, i.e. when the brake pads 16 come into contact with the brake pulley 17, a force occurs in the load 11, which is sensed by the force sensor 10, which causes a decrease in the voltage drop across it, and therefore an increase in the voltage on the coil of the intermediate relay 7, contacts 8 of which This closes and connects a pulse generator with 3 pulses to the input of the pulse counter 5. From this point on, counter 5 begins counting the deceleration time. The contacts 14 of the relay 15 are thus closed, since the relay 15 is included in the stator circuit of the drive motor of the mechanism. The voltage on the stator windings of an electric motor does not disappear after the latter is disconnected, but is maintained due to the imposing electromotive force due to the rotor turning (rigidly connected with the brake pulley 17) until the pulley stops. When the pulley is completely stopped, the voltage in the stator circuit becomes equal to zero and the contacts 14 of the relay 15 open, disconnect the generator of 3 pulses from the counter 5 pulses. In this way, the number of pulses is recorded, which is proportional to the time interval from the start of braking (the first contact between the pads and the pulley) until the brake pulley is completely stopped.

The accuracy of the measurement of the response time and deceleration time is achieved due to the high sensitivity of the force sensor, which allows you to accurately record the moment of force in the pull when you first contact the pads with the brake pulley. This moment is final when measuring the response time and initial when measuring the deceleration time.

Thus, the proposed device registers the number of pulses, proportional to the response time, and the number of pulses, in proportion to / W ///

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Claims (1)

SUMMARY OF THE INVENTION A device for diagnosing brakes of hoisting machines, comprising a brake actuator switch, a pulse generator, a pulse counter, a power source and a switch, characterized in that, in order to improve the accuracy of measuring the braking time, the device is equipped with a force sensor mounted on a link between the strut 5 brakes and a nut on the outside of the brake and electrically connected to an intermediate relay, normally closed contacts of which are included in the 1θ pulse counter control circuit Yemeni response, and the normally open contacts - the counter circuit control pulses for deceleration time, and the entrance 15 · SEQ it is included in the stator of the motor drive chain mechanism for torus · to set the brake.