Backstop

タイトルまたは説明

Introduction
Non-return device is a kind of device to anti-reverse, which is a security protective device on lifting equipment. In general, it is adopted for the equipments e.g. lifting belt conveyor, bucket hoister, scraper conveyor and other equipments with non-return requirements.

Application and Features
In accordance with the bonding conditions of the inner and outer circles of cam of working elements in overrunning, clutch is further divided into contact and non-contact types. In general, contact type clutch is often used in low speed working conditions. During high speed working conditions, oil lubrication, special structure and materials of cam are commonly used. In general, non-contact type clutch is often used in medium or high speed working conditions, and mechanical clutch is adaptable to meet various requirements. The clutch series can be used in a wide range, including a series of uses such as overrunning, indexing and non-return, etc.

Non-return device is a kind of device to anti-reverse, which is a security protective device on lifting equipment. In general, it is adopted for the equipments e.g. lifting belt conveyor, bucket hoister, scraper conveyor and other equipments with non-return requirements.

Clutch mainly consists of inner circle, outer circle, cam, accumulating spring, sealing ring and end cap, etc. According to working elements and support mode, clutch can be divided into following two kinds, one is slide clutch with star wheel, roll ball and outer circle, therefore the series is also called roller clutch series. The other one is slide clutch with circular orbit formed by special shaped blocks in inner circle and outer circle (there is also a series without inner circle, which is called axial type), therefore the series is also called cam clutch series. The working principle of mechanical clutch is to adopt wedge principle; cam is laid in circular orbit formed with inner circle and outer circle by following certain regularity. And working surface of cam touches the inner circle and outer circle due to accumulating spring gives load to ensure the instant meshing in force moment delivery. With the effect of cam wedging between the inner circle and outer circle, the force moment makes the inner circle and outer circle shrink and is delivered to other mountings or basis to bear the load of moment.

According to the force form, the accumulating spring of clutch working elements can be divided into following five kinds: compression accumulating spring, stretching accumulating spring, annular compression accumulating spring, annular stretching accumulating spring and torsion accumulating spring. Due to some clutch series are equipped with two groups of ball bearing between inner circle and outer circle, concentricity of inner and outer circles can be controlled effectively so as to ensure that locking device can uniformly bear load and high speed running and make the service life of clutch longer.

Clutch is divided into three categories based on usage: overrunning clutch, intermittent feeding device (indexing mode) and non-return device. It also can be sub-divided according to rotary speed, feeding distance and load conditions, etc. Selecting appropriate clutch based on application working conditions is very important.

According to application conditions of clutch in following table, please choose the best series of clutch. If you need clutch with special task, please contact us.  

1. Overrunning clutch: it is a service device which can be exchanged randomly in following two conditions, one is that clutch engages and delivers non-return force moment, the other is that rotary speed difference and different rotating direction of outer circle continues idling.

2. Intermittent feeding device (indexing mode): it is also called interrupted feeding of indexing mode. Transfer certain cycle motion of outer circle into intermittent rotary motion and deliver to inner circle (axial) alternately. According to feeding length, frequency and loading conditions, high-frequency mesh and idling devices can be divided into six types.

3. Non-return device: it can be called anti-reversing device to prevent from mechanical reverse. In clutch idling or occasional reverse in mechanical movement, it shall be mesh.

Specification