RU2499925C2 - Cable shock-absorber manufacturing method - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: internal plates are installed on a mandrel. Cable drawing is performed; for that purpose, one cable end is fixed on the mandrel, and the other one is engaged with a load. The cable is wound into a spiral on a mandrel so that internal plates are located at diametrically opposite spiral points. External plates are installed on the cable spiral. Internal and external plates are attached to each other. Plates are provided with semi-circular cavities for the cable. The mandrel is provided with slots for installation of internal plates preventing their lateral displacement.

EFFECT: providing a detachable connection of shock absorber parts; reducing the number of process equipment for assembly; uniform tightening of a cable on all of its turns.

3 cl, 8 dwg

Description

The invention relates to the field of protection of objects for various purposes (spacecraft, engines, devices and other products) from the effects of dynamic loads. The invention can be successfully applied in any field of technology, taking into account the design features of vibration-insulated objects.

A known method of manufacturing a cable shock absorber according to the patent of Russia RU No. 2305809 (third option), which is adopted as a prototype. A method of manufacturing a cable shock absorber is that a steel cable is wound onto wave-shaped curved ring plates into specially provided recesses by means of a mandrel, while the cable is wound so that it enters the recesses of the plates at diametrically opposite points of the spiral. Then, two metal plates are mounted on the spiral of the cable and a pair of plates (internal and external) are fastened together by an integral connection. The permanent connection between the cable and the plates is performed by compressing each pair of plates, while the smallest distance in the oval holes for the cable is in the range of 0.7-0.8 cable diameters. Next, take out the mandrel.

The disadvantages of the prototype are the following:

- the smallest distance in the holes of the plates for the cable is selected in the range of 0.7-0.8 of the diameter of the cable, which deforms the cable with its tight compression and increases its wear during operation;

- to ensure a permanent connection between the plates and the cable, structural deformation and an additional tool are required to perform this operation;

- after testing, in case of discrepancy with the specified technical characteristics, the cable shock absorber must be disposed of, since the integral connection between the plates and the cable prevents disassembly of the cable shock absorber and re-winding of the cable.

The aim of the invention is to remedy these disadvantages of the prototype by improving the quality of manufacture of a cable shock absorber.

The goal is achieved due to the fact that:

- plates with recesses (inner plates) are placed on the mandrel;

- the cable is placed in the recesses of the internal platinum and the cable is wound into a spiral so that the plates are located at diametrically opposite points of the spiral;

- set the outer plate on the cable spiral;

- fasten the inner and outer plates;

- before assembling the shock absorber, the steel cable is drawn to stabilize and evenly distribute the wires in the cable;

- the radius of the recesses of the plates for the cable is selected in the range of 0.95-0.98 radius of the cable to minimize deformation and wear of the cable during operation;

- when winding the cable, one end of the cable is secured to the mandrel structure, and the technological load is hung on the other end to uniformly stretch the cable in all its turns;

- after the assembly of the cable shock absorber, tests are carried out by assessing the stiffness of the cable shock absorber by the method of static loading by the force of the perpendicular plane of the plates to determine the bearing capacity for compliance with the calculated value;

- after testing, in case of discrepancy with the specified technical characteristics, the cable shock absorber is disassembled and the rope rewound, which does not require additional costs for the manufacture of shock absorber plates.

The technical result of the invention is the expansion of manufacturing technology of a cable shock absorber, the introduction of a steel cable hood to improve its quality and the introduction of tests of a cable shock absorber to determine the bearing capacity for compliance with the calculated value.

The invention is illustrated by drawings, which depict:

figure 1 - the location of the objects involved in the winding of a steel cable, before starting the winding;

figure 2 is an embodiment of the mandrel;

figure 3 is an embodiment of the mandrel;

figure 4 - the location of the objects involved in the compression of the steel cable with external plates, after winding;

figure 5 - the final operation of the assembly of the cable shock absorber;

Fig.6 is a diagram of the static loading of a cable shock absorber.

The method is as follows.

Before assembling the cable shock absorber, the steel cable 6 is drawn out, for this purpose one end of the cable 6 is engaged with the crane hook, and the other with the process load 8, the mass of which is selected taking into account the breaking force of the cable 6. When pulling the cable 6, under the action of the mass of the load 8, stabilization and uniform distribution of the wires in the cable 6 occurs. For example, the optimal drawing of the cable 6 is performed within 10 minutes. At the end of the extraction of the cable 6, it is necessary to check the cable 6 with an external inspection for wire breaks, individual strands and other mechanical damage.

After drawing the cable 6, it is wound, shown in FIG. 1, onto the inner plates 1 and the assembly of the cable shock absorber, for this:

- the inner plates 1 are installed in the groove of the mandrel 2 and are fixed to the mandrel using fasteners 3 (bolts, screws or others);

- the mandrel 2 is fixed in the cartridge 4 and is tightened by the tailstock 5 of the lathe;

- one of the ends of the cable 6 is fixed on the mandrel 2;

- the loose end of the cable 6 is threaded through the roller 7 and is engaged with the technological load 8 to create a cable tension;

- the speed of rotation of the spindle with a fixed chuck 4 of the lathe is set in the region of 10 revolutions / min;

- the cable 6 is winded onto the inner plates 1.

Note: plates (internal and external) with nine semicircular recesses for the cable, selected in the range of 0.95-0.98 radius of the cable. The plates are made with a width selected in the range of 2.0-2.5 cable diameter;

- fasteners 3 (bolts, screws or others) are unscrewed from the inner plates 1.

Note: when performing the winding of the cable on the inner plates of the shock absorber as a mandrel, on which the inner plates are fixed, the constructive options shown in FIG. 2 and FIG. 3 can be used.

The mandrels shown in FIGS. 2 and 3 are made in the form of a workpiece with attachment points on a lathe, which must be dimensioned to provide the desired distance between the inner plates of the cable shock absorber, the contact of the contact surface of the inner plates of the shock absorber with the mandrel (without deformation plates) and the fit of the cable under the desired radius.

The structural difference of the mandrels (figure 2 and figure 3) is that the mandrel (figure 2) has a groove under the inner plate of the cable shock absorber, preventing lateral displacement of the plates.

After winding the cable onto the inner plates, the cable is crimped by the external plates and secured to the internal plates, shown in figure 4, for this:

- outer plates 9 are installed and fixed on the inner plates 1 with screws 3;

- the cable 6 is disengaged from the technological load 8;

- the mandrel 2 is removed from the lathe;

- the cable is cut at a distance of ≈2 mm from the lateral surface of the plates 1 and 9 at the exit point of the cable to the outside;

- the cable shock absorber is released from the mandrel 2.

Next, the final operation of assembling the cable shock absorber shown in Fig. 5 is performed, for this purpose, studs 10 are installed in plates 1 and 9.

The seemingly simple simplicity of the described technology of drawing and winding the rope comprises complex design studies, the correctness of which is confirmed after testing the cable shock absorber.

The test of the cable shock absorber, shown in Fig.6, is carried out for its rejection by assessing the stiffness of the cable shock absorber by static loading with a force perpendicular to the plane of the plates to determine the bearing capacity for compliance with the calculated value.

The test rig provides compression and extension of the cable shock absorber only in the vertical direction to assess its actual stiffness and bearing capacity, and the side walls of the test rig prevent it from shifting from the vertical axis. On the bottom of the test rig one of two devices 11 is installed with through holes for the studs 10 of the cable shock absorber, to prevent damage to the studs under the action of force P. Before testing, the size between the inner plates 1 of the shock absorber is measured. Applying a load P with a resolution of 20 kg, the size between the inner plates 1 is measured after each loading. At each loading, the structure is maintained for 1 ÷ 2 minutes. The load of the shock absorber continues until the contact of its inner plates 1 with each other. In case of discrepancy to the expected change in the height of the shock absorber during each loading until the contact of its plates, the shock absorber is disassembled and the rope rewound. A plot of the stiffness of the shock absorbers is constructed and the maximum stiffness value is determined from it.

By the maximum change in the height of the shock absorber at the maximum load at which the shock absorber starts to work in the elastic zone without permanent deformation, the value of maximum stiffness is determined.

The actual value of the bearing capacity of the cable shock absorber is determined by the formula $$R_{f\mathrm{but}\mathrm{to}}=\frac{{\mathrm{<figure-callout\; id="1"\; label="R\; max"\; filenames="00000003.png,00000006.png"\; state="\{\{state\}\}"><figure-callout\; id="5"\; label="R\; max"\; filenames="00000003.png"\; state="\{\{state\}\}">R\; </figure-callout></figure-callout>}}_{\max }}{\mathrm{1,5}}$$

where P _max is the ultimate load at which the shock absorber begins to work in the elastic zone without permanent deformation.

Upon completion of testing the cable shock absorbers, depending on their actual bearing capacity, the optimal number of cable shock absorbers for the shock absorption system is determined in order to perceive the given mechanical load.

Claims (3)

1. A method of manufacturing a cable shock absorber, consisting in the fact that the inner plates with recesses are placed on the mandrel, the cable is twisted into a spiral on the mandrel so that the inner plates are located at diametrically opposite points of the spiral, the cable is placed in the recesses under the cable, installed on the cable spiral outer plates fasten the inner and outer plates, characterized in that before assembling the shock absorber, the cable is drawn and coiled, securing one end of the cable to the mandrel, and the other engaging with the load, while The equalization can be performed with grooves for installing the inner plates of the cable shock absorber, preventing their lateral displacement, and the plates are made with semicircular recesses for the cable. 2. A method of manufacturing a cable shock absorber according to claim 1, characterized in that after assembling the cable shock absorber, it is tested, for example, by assessing the stiffness of the cable shock absorber by the method of static loading by force perpendicular to the plane of the plates to determine the bearing capacity for compliance with the calculated value. 3. A method of manufacturing a cable shock absorber according to claim 1, characterized in that the recesses for the cable are selected in the range of 0.95-0.98 radius of the cable.

Images