RU208452U1 - Double Acting Hydraulic Cylinder with Hydrostatic Guides - Google Patents

Abstract

The utility model relates to the field of hydraulic equipment and can be used in technological equipment, mainly in hydraulic drive systems of bench test equipment for multi-cycle testing of critical parts for various purposes. The technical result of the proposed hydraulic cylinder is aimed at ensuring maintainability, by installing wiper rings in the auxiliary flanges, which will allow the replacement of wiper seals when worn without complete disassembly of the hydraulic cylinder. The technical result is achieved by the fact that the double-acting hydraulic cylinder with hydrostatic guides contains a housing with two covers and flanges, a piston with a double-sided rod, the rod surface is made with a hard-chrome coating, while the piston is made with the possibility of reciprocating motion in the form of a single part with labyrinth sealing grooves, the inner surface of the housing, along which the hydraulic cylinder piston moves, is made with a hard chromium coating, the hydrostatic bearings are made in the form of a bushing and are installed in the flanges, a feedback sensor is built into the housing through the base, channels for supplying and discharging the working fluid are made in the covers and flanges, according to useful model, each bushing is hardened, contains four load-bearing pockets evenly distributed along the inner circumference, and is equipped with inlet chokes, annular grooves and technological holes, while the wiper seal is installed in the auxiliary flange. 2 ill.

Description

The utility model relates to the field of hydraulic equipment and can be used in technological equipment, mainly in hydraulic systems of drives of bench test equipment for conducting multi-cycle tests of critical parts for various purposes.

It is known from the prior art that chromium plating is widely used to increase the hardness and wear resistance of rubbing parts of devices and machines. For example, a hydraulic cylinder rod with a hardened surface is known (RF patent No. 26829, IPC F16J 7/00. Publ. 20.12.2002), on the working surface of which a protective layer of chromium is applied.

Known from the prior art is a hydraulic cylinder containing a housing, a piston with a rod (RF patent No. 10743, IPC F16J 10/00, publ. 08.16.1999). The surface of the cylinder rod is made with a hard chrome plating, the cylindrical part of the cover, which mates with the rod and the body, has an elongated section.

The closest in technical essence to the claimed technical solution is a double-acting hydraulic cylinder with hydrostatic guides (RF patent No. 199474, IPC F15B 15/14, publ. 09/02/2020), containing a body with two covers, a piston with a double-sided rod, the piston surface is made with a hard chromium coating, and the piston is made with the possibility of reciprocating movement in the form of a single piece with labyrinth sealing grooves, the inner surface of the body, along which the piston of the hydraulic cylinder moves, is made with a hard chromium coating, hydrostatic guide rods are installed in both covers, made in the form of hydrostatic bearings , a feedback sensor is built into the body through the base, while in the covers and hydrostatic bearings there are channels for supplying and removing the working fluid.

Disadvantages of this technical solution: The use of adjustable individual throttling devices requires a one-time superstructure, and their installation in the covers requires a strict internal arrangement of channels for supplying and removing the working fluid to the hydrostatic bearings, which leads to an increase in the overall dimensions of the product. Also, an exact relative positioning of technological pressure holes in hydrostatic bearings with holes located in the covers is required, which increases the labor intensity of the technological process of assembling the product. To replace the wiper rings, a complete disassembly of the hydraulic cylinder is required, which increases the time for repair and replacement.

The technical problem of the proposed hydraulic cylinder is aimed at reducing the overall dimensions of the device and reducing the time for repair (replacement) of wiper seals.

The technical result of the inventive hydraulic cylinder is aimed at ensuring maintainability by installing wiper rings in auxiliary flanges, which will make it possible to replace wiper seals when worn without complete disassembly of the hydraulic cylinder.

The technical result is achieved in that a double-acting hydraulic cylinder with hydrostatic guides contains a body with two covers and flanges, a piston with a double-sided rod, the surface of the rod is made with a hard chromium coating, while the piston is made with the possibility of reciprocating movement in the form of a single piece with labyrinth sealing grooves, the inner surface of the body, along which the piston of the hydraulic cylinder moves, is made with a hard chromium coating, the hydrostatic bearings are made in the form of a sleeve and are installed in the flanges, a feedback sensor is built into the body through the base, in the covers and flanges there are channels for supplying and removing the working fluid, according to utility model, each bushing is hardened, contains four bearing pockets, evenly distributed around the inner circumference, and is equipped with inlet chokes, annular grooves and technological holes, while the wiper seal is installed in the auxiliary flange

The presence of a hardened sleeve with four bearing pockets evenly distributed around the inner circumference, the presence of inlet throttles, annular grooves and technological holes provides a high-pressure supply of a working fluid from a single source, its uniform distribution and subsequent removal from a single source.

Protection against contamination is provided by a wiper seal installed in the auxiliary flanges, and this will allow replacing the wiper seals when worn without completely disassembling the hydraulic cylinder, ensuring good maintainability of the product as a whole.

Replacement of compact throttling devices from adjustable to unregulated input chokes (hereinafter referred to as input chokes) is aimed at reducing the overall dimensions, which is achieved by installing throttling devices directly into the hydrostatic bushing, thereby eliminating the need for an auxiliary superstructure of throttling devices, and the need for precise mutual positioning of supply process pressure passages made in flanges and hydrostatic bushings, due to a common annular groove through which fluid under pressure enters the throttling device, and then into the pocket of the hydrostatic bushing.

The essence of the proposed technical solution is illustrated by graphic material, where in Fig. 1 shows a longitudinal section of a hydraulic cylinder with hydrostatic guides, FIG. 2 shows a fragment of a cover as part of a double-acting hydraulic cylinder with hydrostatic guides: 2a - general view (longitudinal section), 2b - section B-B, 2c - view A.

The positions in FIG. 1, fig. 2, the following elements are indicated: body - 3, piston-rod with labyrinth sealing grooves - 4, hydrostatic bearings, including sleeve 1 (the second sleeve is conventionally not shown) and cover 2 (the second cover is conventionally not shown). Bushings 1 are made in the form of a hardened part with four bearing pockets 7 (Fig.2a), evenly distributed around the inner circumference, with inlet chokes 5 (Fig.2c), annular grooves 10, 11, 12 and 13 and a drain hole 14 (Fig. 2a, b). Working fluid under pressure is supplied to the carrier pockets 7 through the inlet throttle 5 and the pressure opening 8 (Fig. 2a). The oil is drained through the drain hole 9.

In the cover 2 (Fig. 2), a channel supplying a working fluid through the pressure opening 8 and a channel for draining the working fluid through the drain hole 9 of the bushings 1 of the hydrostatic bearings are made. A feedback sensor is built into the housing 3 through the base (not shown in Fig. 1 and Fig. 2).

The bushing 1 is located coaxially with the body 3 and is closed by a cover 2. To supply the working fluid under high pressure and to drain it, a pressure hole 8 is located in the cover 2, through which the liquid enters the common annular groove 10. This technological solution uses the power supply of the carrier pockets 7 from one source of high pressure, therefore, an inlet throttle 5 is installed in front of each pocket, which together provide the required pressure drop. From the bearing pockets 7 and the high-pressure working chamber, the working fluid flows through the annular gaps formed between the joint arrangement of the bushings 1 and the piston-rod 4, into the annular grooves 12 and 13, after which it flows through the drain hole 14 into the annular groove 11, from where it is removed by the auxiliary pump through the drain hole 9. The tightness of the end and cylindrical connections is ensured by O-rings 15. To prevent contamination along the piston, a wiper is installed from the end in the flange 16 (Fig. 2b) 6. Due to the formed film between the sleeve 1 and the piston-rod 4, it is significantly reduced wear of the contacting parts and the friction force between them.

A double-acting hydraulic cylinder converts the hydraulic energy of the working fluid into mechanical energy of the reciprocating movement of the hydraulic cylinder piston. When fluid is supplied under pressure to the working chambers, which acts on the ends of the one-piece piston-rod 4 of the hydraulic cylinder, an axial force arises, which tends to move the piston 4 to the extreme position. By supplying pressure alternately to the working chambers, the piston-rod moves to the extreme positions. Depending on the volume of fluid supplied to the working chambers of the hydraulic cylinder, it is possible to install the piston-rod in any of the intermediate positions. The piston rod 4 of the hydraulic cylinder moves in hydrostatic bearings. Each hydrostatic bearing is made with four pockets 7, to which the working fluid is supplied under pressure through the inlet throttles 5. Due to this, there is no friction and wear, since there is always a film of the bearing operating fluid, including before the start of movement, and is maintained under all loading conditions up to certain transverse forces (critical, which are no longer able to withstand hydrostatic bearings). Further, the liquid is discharged through drain channels 9 and 14. Control of the position of the hydraulic cylinder rod with a predetermined accuracy is provided by a built-in feedback sensor. The thickness of the hard chromium coating on the outer surface of the stem and on the inner surface of the body is from 20 to 42 microns. The hardness of the hard chrome coating on both parts is 850 ... 1100 HV.

The inventive hydraulic cylinder provides maintainability, eliminating the need for adjusting throttling devices, as well as a compact design.

Claims (1)

A double-acting hydraulic cylinder with hydrostatic guides, containing a body with two covers and flanges, a piston with a double-sided rod, the surface of the rod is made with a hard chromium coating, while the piston is made with the possibility of reciprocating movement in the form of a single piece with labyrinth sealing grooves, the inner surface of the body , along which the piston of the hydraulic cylinder moves, is made with a hard chromium coating, in both covers there are hydrostatic guide rods made in the form of hydrostatic bearings, a feedback sensor is built into the housing through the base, in the covers and flanges there are channels for supplying and withdrawing the working fluid, characterized by the fact that that the hydrostatic bearings are made in the form of a sleeve and are installed in flanges, each sleeve is hardened, contains four bearing pockets, evenly distributed along the inner circumference, and is equipped with inlet chokes, annular grooves and technological holes, with the wiper seal installed in the auxiliary flange.

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