SU979749A2

SU979749A2 - Shoe brake

Info

Publication number: SU979749A2
Application number: SU813251075A
Authority: SU
Inventors: Георгий Владимирович Бежок; Леонид Яковлевич Будиков; Сергей Николаевич Шевченко
Original assignee: Ворошиловградский машиностроительный институт
Priority date: 1981-02-25
Filing date: 1981-02-25
Publication date: 1982-12-07

Description

(54) КОЛОДОЧНЫЙ ТОРМОЗ(54) BRAKE PADS

1one

Изобретение относитс к тормозам и может найти применение в подъемно-тракторных машинах.This invention relates to brakes and can be used in hoisting and tractor machines.

По основному авт. св. № 837924 известен колодочный тормоз, содержащий тормозйые колодки, замыкающую пружину, 5 приводное устройство, выполненное в виде соленоидного электромагнита без магнитопровода , подключенного к источнику посто нного тока, и снст-ему управлени приводным устройством, обеспечивающую из- д менение силы тока в катушке электромагнита с помощью детали управлени 1.According to the main author. St. No. 837924 is known a drum brake containing brake pads, a closing spring, 5 a drive device made in the form of a solenoid electromagnet without a magnetic conductor connected to a direct current source, and a control device for driving a device that provides a change in current in the coil of an electromagnet using control details 1.

Недостатком известного тормоза вл етсн невозможностъ обеспечени и замыкани тормоза с йараст-анием тормозного момента по заданной программе. Как известно, 5 при замыкании такого тормоза в автома;ическом режиме, т. е. при отключении питани электромагнита, прижатие колодок к тормозному щкиву осуществл етс усилием сжатой пружины и весам кор , при 2о этом все подвижные части тормоза разгон ютс и перед соприкосновением колодок са шкивом обладают относительно большой кинетической энергией, так как системы рычагов и колодок велика, то происходит удар колодок о щкив. Эти ударные нагрузки при замыкании колодок могут превышать статические в 2,5-3 раза.A disadvantage of the known brake is the impossibility of providing and closing the brake with a braking torque according to a given program. As is well known, 5 when closing such a brake in an automatic mode, i.e., when the power of the electromagnet is disconnected, the pads are pressed against the braking tongue by the force of the compressed spring and the weights of the core, at 2 ° this all moving parts of the brake accelerate before the pads touch Since the pulley has a relatively large kinetic energy, since the system of levers and pads is large, then the pads are struck against the cheek. These shock loads when closing the pads can exceed the static by a factor of 2.5-3.

Целью изобретени вл етс улучшение тормозных характеристик колодочного тормоза .The aim of the invention is to improve the brake performance of the shoe brake.

Поставленна цель достигаетс тем, что в колодочном тормозе источник посто нного тока выполнен в виде тиристорного управл емого выпр мител , и система управлени тормоза - в виде подключенных параллельно На вход последнего размыкающего элемента и нелинейного блока, включающего конденсатор и по крайней мере две нелинейных чейки, подключенных к обкладке конденсатора, соединенной с тиристорным управл емым выпр мителем.The goal is achieved by the fact that in the block brake the DC source is made in the form of a thyristor controlled rectifier, and the brake control system is connected in parallel To the input of the last disconnecting element and a nonlinear unit including a capacitor and at least two nonlinear cells, connected to the capacitor plate connected to a thyristor controlled rectifier.

На фиг. 1 изображена схема тормоза; на фиг. 2 - схема нелинейного блока..FIG. 1 shows the brake circuit; in fig. 2 is a diagram of a nonlinear block ..

Claims

A block brake consists of brake pads 1, a system of levers 2, a closing spring 3, a driving device 4, to the coil input of which an ac thyristor controlled rectifier 5 connected to the closing element 6 is connected via a nonlinear block 7 containing the connected parallel to the closing element, a capacitor 8, to one of the plates of which is connected the input of a thyristor controlled rectifier and two or more nonlinear cells 9 connected in parallel to each other 9. The brake operates the following m way. In the open position, the closing element 6 is closed, while the capacitor 8 is discharged, the first non-linear cell is open, i.e. is in operating condition, the voltage at the input of the thyristor control of the rectifier is maximum, the current in the coil is also maximum, and the driving rod devices pushed out. To close the brake, it is necessary to open the closing element 6, the capacitor starts charging at the same time, the voltage at the input of the thyristor controlled rectifier decreases. This signal is applied to the driver of the drive device 4, the amount of current in which will begin to decrease, the drive force of the drive device will also decrease and, under the action of the force of the compressed spring and the weight of the core, the rod of the drive device will begin to move downwards. This movement will cause the pad to approach the brake pulley. When the potential on the capacitor plate reaches a value equal to the threshold voltage of cell I, the latter is disconnected from the charging circuit of the capacitor. The cell II, which is tuned to the same voltage value, is connected to the charge circuit of the capacitor, as a result of which the rate of increase of the charge of the capacitor decreases, resulting in a slower decrease in the current in the drive coil and, consequently, the tractive effort of the latter. And since the magnitude of the braking torque is proportional to the positive difference between the accelerations of the spring and the pusher, the braking torque will begin to gradually increase. When the potential on the capacitor plate reaches a value equal to the threshold voltage of the next cell, the latter is also connected to the charging circuit of the capacitor. In this case, the rate of increase in the charge of the capacitor increases, therefore, the magnitude of the braking torque will increase more intensively. All subsequent non-linear cells work in the same way. After the last cell has triggered, the capacitor is fully charged, the drive force is zero, and the braking torque is at its maximum. The brake is inhibited. When the opening element 6 is closed, the brake is released. The proposed brake, providing the braking moment to the plant according to a given program, allows one to obtain optimal braking characteristics and thereby ensure an accurate stop of the mechanics. reduce the swinging of the load, which in turn improves the performance of the machines, reduces the dynamic loads on the drive and the metal construction, increases the durability of the machines, improves the working conditions of the crane driver. Claims of invention No. 837924, characterized in that, in order to improve its braking characteristics, the DC source is designed as a thyristor controlled rectifier, and the brake control system is connected in parallel. To the input of the last disconnecting element and a nonlinear block including a capacitor and at least two nonlinear cells connected to the capacitor plate connected to a thyristor controlled rectifier. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 837924, cl. In 66 D 5/00, 1979 (prototype).

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