The cable jack is a large lifting mechanism that performs the function of lifting the cable drum to a specific height. As a rule, the value of the lifting height is not very large and is only a few centimeters. This tool is used as a transfer device when rewinding or laying a cable.
Device
The cable jack (DK 5V including) has a very primitive design, which consists of the following parts:
- racks;
- lodgement;
- lifting gear and axle.
Design Features
The cable jack operates as follows. Through the central hole of the drum in the device, a hole is made for the axis of the jack onto which centering sleeves or cones are mounted. In this case, special clamping shoes move along this axis to the cheeks of the rotating drum and are fixed with a clamp. Racks are mounted on this device on both sides. Thus, they provide a working gap between the structure of the rack and the cheek of the drum. As a rule, this value does not exceed the mark of 10 centimeters. Why is it impossible to install a larger clearance on a cable jack (DK 5 including)? The fact is that with increasing distance between these two devices the bending moment of the axis will increase, and this, in turn, can lead to breakdown and failure of the entire mechanism.
As for the lodgements, they are combined with the axis of the cable drum and are used as a lifting mechanism. It doesn’t matter, screw is a pair or a hydraulic system. The height of the coil is about 50-100 millimeters.
Varieties
There are several types of device data:
Each of these devices has its own principle of operation. To understand the design features of each, we consider all three types separately.
Let's start with devices that have a screw drive system. Such a cable jack works on the principle of a screw pair, in which, when lifting the coil, the nut carries out rotational movements, and the screw - translational.
Hydraulic devices are special in their own way. Their design involves the presence of a special hydraulic cylinder or jack, which serves as the main lifting mechanism. In such tools, the process of raising the coil occurs by reciprocating movements of the hydraulic jack handle or the hydraulic station.
Lever devices are a set of jacks in which the cable drum is lifted using a special lever. All efforts are assigned to this part, which develop due to the difference in the shoulders of the tool tray and the handle relative to the central point of support.
Thus, a cable jack is a mechanism that can lift a cable drum with various devices to one or another height, but not more than 50 or 100 millimeters.