Rope hoist is one of the procedures specified "no pull oblique hanging crooked", but in the actual lifting process, due to the construction workers working conditions, work experience or objective conditions caused widespread pulled oblique hanging crooked phenomenon. Once that happens, it is easy to damage the rope hoist, ranging from making cable, wire rope scrapped, while in the whole rope hoist scrapped or personal injury, resulting in some economic loss, seriously affecting the construction production. At present, none of the design of all rope hoist lifting device against crooked pulled oblique, so there are significant security risks.
First, the design of anti-pull oblique hanging crooked safety device
For such problems exist in the work, in practical work designed a pulled oblique hanging crooked can prevent a device, the device is the use of oblique hanging crooked pull rope when a certain deflection angle, so that the rope hoist mounted on limit switches work, which automatically disconnect lifting contactors, limit lifting capabilities.
This device not only has anti hanging crooked pull ramp function, but also has a high limit function. The practice of using the operation, the effect is very good, reliability is also high, pulled oblique hanging crooked can prevent the phenomenon.
Second, the structural design
1, the mechanical part
The device consists of the mechanical part of Shengka @ 15mm, 2 welded assemblies with a stopper components. 1 Shengka is soldered with the balance wheel relative to the center of the arc at the lowest point of the housing (on the rope hoist), the component l and the stopper is fixed by means of bolts, and the component 2 is fixed to the balance Shengka Round 2 rope (rope under 2 will not change this characteristic spacing), and finally by adjusting the position of a component, making travel limit feeler placed vertically in the center hole assembly 2.
(A) design principles to be taken into account in any one direction can play a protective function, so in the design of component 2, the center of its design into a round hole, thus making all directions pulled oblique hanging crooked anti-skew angle of the same; You can also use a 360. Within the scope of the work to achieve the limit switch off the action, thereby protecting
Wire rope hoist from damage.
Anti pulled oblique hanging crooked setting angle 4. Component 2 is fixed on a wire 5. Anti-travel limit switch contact lever pull oblique hanging crooked size of the angle to be adjusted according to the actual working conditions, For the angle becomes large, there are three methods: the expansion of the central hole assembly 2; the lower sensitivity limit switch; Component 2 will be slightly upwards. To transfer a small need to increase the sensitivity of the limit switch assembly 2 or slightly down shift.
(2) Work First, according to the actual work situation, set the appropriate skew angle rope, when pulled oblique hanging crooked angle greater than the set value, the skewness of the rope was enough to make the center hole assembly 2 hole edge touches the limit contact bars, cause limit work, cut off rope hoist lifting contactor control circuit, which play a protective role. Once inside the rope back to the set value, the limit is also touch lever back into place, namely lifting contactor return to work.
2, the electrical part
c1 is lifting contactors, c2 is decreased contactors. The main circuit is powered, press A1, c1 to work, lifting hook. When hanging crooked pulled oblique angle is greater than the value of the limit switch settings, sT contacts open, c1 contactor to stop working, ie lifting hook to stop time, press A2, c2 can work, then hook only fall not rise, and thus play a protective role.
The height limit function of the device is in the lifting operation, if failure occurs due to malfunction of firearms off, at which point the driver's thoughts without concentration, did not release the A1, so keep lifting hook. When the hoist hook fast approaching, the time has also been close hook travel limit switch contact bars, resume a lift, it will surely bring feeler shifted or on the roof, causing ST disconnect, C1-off coil along electricity, also stopped lifting hook, played height limit function.
The device to be tested in practical applications, and the simple, practical, easy to install, low cost, high reliability, energy 360. Played within the scope of protection and off the fire stopper in failure, but also play a height limiter function, rope hoist play a very good safety results.