RU2511925C1 - Differential composite piston (versions) - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: proposed group of inventions relates to the field of machine building, namely, to compressor building, and may be used in cylinders of different purpose, in particular, in cylinder-piston units of piston compressors. A differential composite piston according to the version 1 comprises a stem (1) with a thrust collar (2), pistons of low (3) and high (4) pressures. The low-pressure piston (3) is made with an axial hole and is placed onto the stem (1) until the thrust collar (2). The high-pressure piston (4) is made as solid and is fixed on the stem (1) at the side of placement of the low-pressure piston (3) with the help of a threaded joint. At the same time the high-pressure piston (4) presses the low-pressure piston (3) to the thrust collar (2) of the stem (1). At the same time between high (4) and low (3) pressure pistons there is a crown-shaped washer (5). A differential composite piston according to the version 2 comprises a stem (1) with a thrust collar (2), pistons of low (3) and high (4) pressures. The low-pressure piston (3) is made with an axial hole and is placed onto the stem (1) until the thrust collar (2). The high-pressure piston (4) is made as hollow and is fixed on the stem (1) at the side of placement of the low-pressure piston (3) with the help of a threaded joint. At the same time the high-pressure piston (4) presses the low-pressure piston (3) to the thrust collar (2) of the stem (1). At the same time between high (4) and low (3) pressure pistons there is a crown-shaped washer (5).

EFFECT: simplified design, and also prevention of self-unscrewing of a high-pressure piston with simultaneous pressing of a low-pressure piston to a thrust collar of the stem.

6 cl, 2 dwg

Description

Technical field

The claimed group of inventions relates to the field of engineering, namely to compressor engineering, and can be used in cylinders for various purposes, in particular in piston-cylinder assemblies of reciprocating compressors.

State of the art

Among the pistons is known, for example, a differential piston (Plastinin P.I. “Piston compressors. Volume 2. Design fundamentals. Designs.” - 3rd ed., Revised and enlarged. - M .: KolosS, publ. 2008, p. .309, Fig.3.3.31. [1]), containing a rod with a thrust collar, on which a low pressure piston is fitted, pushing from the opposite side by bolts through the ring gasket to the same thrust collar of the rod. A high pressure piston is installed at the end of the rod, and self-installation of the piston is possible due to gaps in its connection with the low pressure piston. In this case, the high pressure piston is constantly pressed against the low pressure piston and there is no transfer of gaps in this connection when the compressor is operating. Low and high pressure pistons are provided with o-rings.

The disadvantage of the analogue [1] is the complex design of the differential piston, in which bolts with an annular gasket are used to fasten the low pressure piston to the rod.

The above analogue [1] is the set of essential features the closest device of the same purpose to the group of claimed inventions. Therefore, it is adopted as a prototype of the inventive composite differential pistons.

Disclosure of invention

The technical result provided by each invention from the claimed group is to simplify the design. An additional technical result provided by each invention from the claimed group is the prevention of self-unscrewing of the high pressure piston while simultaneously pressing the low pressure piston to the thrust shoulder of the rod.

An additional technical result provided by the invention according to embodiment 1 is the possibility of using a high pressure piston at ultrahigh pressures.

An additional technical result provided by the invention according to option 2 is the reduction of material consumption.

The essence of the invention according to option 1 is that the composite differential piston contains a rod with a thrust shoulder, low and high pressure pistons. The low pressure piston is made with an axial bore and is mounted on the rod to the stop collar. The high pressure piston is solid and fixed to the rod from the side of the low pressure piston by means of a threaded connection. In this case, the high pressure piston presses the low pressure piston against the thrust shoulder of the rod. At the same time, a castellated washer is located between the high and low pressure pistons.

The low pressure piston is preferably hollow with stiffeners.

Low and high pressure pistons can be provided with grooves for O-rings.

The essence of the claimed invention according to option 2 is that the composite differential piston contains a rod with a thrust shoulder, low and high pressure pistons. The low pressure piston is made with an axial bore and is mounted on the rod to the stop collar. The high pressure piston is hollow and mounted on the rod from the side of the low pressure piston by means of a threaded connection. In this case, the high pressure piston presses the low pressure piston against the thrust shoulder of the rod. At the same time, a castellated washer is located between the high and low pressure pistons.

The low pressure piston is preferably hollow with stiffeners.

Low and high pressure pistons can be provided with grooves for O-rings.

Brief Description of the Drawings

Figure 1 shows a diagram of a composite differential piston according to option 1, a longitudinal section; figure 2 is a diagram of a composite differential piston according to option 2, a longitudinal section.

The implementation of the invention according to option 1

The differential composite piston of embodiment 1 (FIG. 1) comprises a stem (1) with a thrust shoulder (2), a low pressure piston (3) and a high pressure piston (4). The low pressure piston (3) is made with an axial bore and is mounted on the rod (1) to the stop shoulder (2). The high pressure piston (4) is solid and mounted on the tail end of the rod (1) from the side of the low pressure piston (3) by means of a threaded connection. A castellated washer (5) is located between the low (3) and high (4) pressure pistons, through which the high pressure piston (4) presses the low pressure piston (3) against the thrust collar (2) of the rod (1). From the end of the high pressure piston (4), on the outside, a groove is made under the tabs of the crown washer (5), which prevents the high pressure piston (4) from unscrewing itself.

The execution of the high pressure piston (4) continuous allows it to be used at ultrahigh pressures.

Example 1

To reduce material consumption, the low pressure piston (3) is made hollow with stiffeners (7).

Example 2

Pistons of low (3) and high (4) pressures are provided with grooves for O-rings (6).

The implementation of the structural elements of the claimed invention according to option 1 is not limited to the above examples.

Job Description for Option 1

Composite differential piston is part of compressor cylinder group. The part of the stem (1), opposite the tail, is fixed in the crosshead. The high pressure piston (4) is placed in the high pressure cylinder, the low pressure piston (3) is placed in the low pressure cylinder. During operation, the composite differential piston performs longitudinal reciprocating movements. Alternately, the low (3) and high (4) pressure pistons move each in its cylinder to its top dead center. Moreover, if the low pressure piston (3) is at top dead center, the high pressure piston (4) is at bottom dead center and vice versa.

When the piston moves from top dead center to bottom dead center, gas enters the cylinder’s displacement through the suction valve. When the piston moves backward, the gas is compressed and exits the cylinder through the discharge valve. Next, the intake cycle, compression is repeated.

In the prototype, the low pressure piston is pressed against the thrust shoulder of the rod using an annular gasket and bolts. In the claimed invention, when the composite differential piston moves to the top dead center of the low pressure piston (3), the high pressure piston (4) presses the low pressure piston (3) against the stop shoulder (2) of the rod (1) through the crown washer (5). In the reverse movement, the low pressure piston (3) is also pressed against the thrust shoulder (2) of the rod (1), and the self-unscrewing of the high pressure piston (4) is prevented by the crown washer (5).

Thus, from the foregoing, it follows that in the inventive composite piston differential according to embodiment 1, the claimed technical results: “simplification of the design”, “prevention of self-unscrewing of the high pressure piston while pressing the low pressure piston to the thrust shoulder of the rod” are achieved due to the fact that the piston the composite differential contains a rod (1) with a thrust shoulder (2), pistons of low (3) and high (4) pressures. The low pressure piston (3) is made with an axial bore and is mounted on the rod (1) to the stop shoulder (2). The high pressure piston (4) is fixed to the stem (1) from the side of the low pressure piston (3) by means of a threaded connection. In this case, the high pressure piston (4) presses the low pressure piston (3) against the thrust shoulder (2) of the rod (1). Moreover, between the pistons of high (4) and low (3) pressures, a castellated washer (5) is located. The claimed technical result: "the possibility of using a high pressure piston at ultrahigh pressures" is achieved due to the fact that the high pressure piston (4) is solid.

The implementation of the invention according to option 2

The differential composite piston according to option 2 (FIG. 2) comprises a rod (1) with a thrust shoulder (2), a low pressure piston (3) and a high pressure piston (4). The low pressure piston (3) is made with an axial bore and is mounted on the rod (1) to the stop shoulder (2). The high pressure piston (4) is hollow and mounted on the rod (1) from the side of the low pressure piston (3) by means of a threaded connection. A castellated washer (5) is located between the low (3) and high (4) pressure pistons, through which the high pressure piston (4) presses the low pressure piston (3) against the thrust collar (2) of the rod (1). From the end of the high pressure piston (4), on the outside, a groove is made under the tabs of the crown washer (5), which prevents the high pressure piston (4) from unscrewing itself.

The implementation of the high pressure piston (4) hollow reduces material consumption.

Example 1

To reduce material consumption, the low pressure piston (3) is made hollow with stiffeners (7).

Example 2

Pistons of low (3) and high (4) pressures are provided with grooves for O-rings (6).

The implementation of the structural elements of the claimed invention according to option 1 is not limited to the above examples.

Job Description for Option 2

Composite differential piston is part of compressor cylinder group. The part of the stem (1), opposite the tail, is fixed in the crosshead. The high pressure piston (4) is placed in the high pressure cylinder, the low pressure piston (3) is placed in the low pressure cylinder. During operation, the composite differential piston performs longitudinal reciprocating movements. Alternately, the low (3) and high (4) pressure pistons move each in its cylinder to its top dead center. Moreover, if the low pressure piston (3) is at top dead center, the high pressure piston (4) is at bottom dead center and vice versa.

When the piston moves from top dead center to bottom dead center, gas enters the cylinder’s displacement through the suction valve. When the piston moves backward, the gas is compressed and exits the cylinder through the discharge valve. Next, the intake cycle, compression is repeated.

In the prototype, the low pressure piston is pressed against the thrust shoulder of the rod using an annular gasket and bolts. In the claimed invention, when the composite differential piston moves to the top dead center of the low pressure piston (3), the high pressure piston (4) presses the low pressure piston (3) against the stop shoulder (2) of the rod (1) through the crown washer (5). In the reverse movement, the low pressure piston (3) is also pressed against the thrust shoulder (2) of the rod (1), and the self-unscrewing of the high pressure piston (4) is prevented by the crown washer (5).

Thus, from the foregoing, it follows that in the inventive composite piston differential according to embodiment 2, the claimed technical results: “simplification of the design”, “prevention of self-unscrewing of the high pressure piston while simultaneously pressing the low pressure piston to the thrust shoulder of the rod”, are achieved due to the fact that the piston the composite differential contains a rod (1) with a thrust shoulder (2), pistons of low (3) and high (4) pressures. The low pressure piston (3) is made with an axial bore and is mounted on the rod (1) to the stop shoulder (2). The high pressure piston (4) is fixed to the stem (1) from the side of the low pressure piston (3) by means of a threaded connection. In this case, the high pressure piston (4) presses the low pressure piston (3) against the thrust shoulder (2) of the rod (1). Moreover, between the pistons of high (4) and low (3) pressures, a castellated washer (5) is located. The claimed technical result: "reduction of material consumption" is achieved due to the fact that the high pressure piston (4) is made hollow.

Industrial applicability

The inventors made a prototype of the claimed composite differential piston, tests of which confirmed the achievement of the technical result.

The inventive composite differential piston is implemented using industrially produced devices and materials, can be manufactured at a machine-building enterprise and will be widely used in piston-cylinder piston compressor assemblies.

INFORMATION SOURCES

1. Plastinin P.I. “Piston compressors. Volume 2. Basics of design. Constructions. ”- 3rd ed., Revised. and add. - M .: KolosS, publ. 2008 (p. 309, fig. 3.3.31).

Claims (6)

1. Composite differential piston comprising a rod with a thrust collar, a low pressure piston with an axial bore, inserted on the rod to the thrust collar, a high pressure piston connected to the said rod, characterized in that the high pressure piston is solid, fixed to the rod from the side fitting the low pressure piston by means of a threaded connection and presses the low pressure piston against the thrust shoulder of the rod, while a crown washer is located between the high and low pressure pistons. 2. The piston according to claim 1, characterized in that the low-pressure piston is made hollow with stiffeners. 3. The piston according to claim 1, characterized in that the low and high pressure pistons are provided with grooves for the sealing rings. 4. Composite differential piston comprising a rod with a thrust collar, a low pressure piston with an axial bore, inserted on the rod to the thrust collar, a high pressure piston connected to said rod, characterized in that the high pressure piston is hollow, is fixed to the rod from the side fitting the low pressure piston by means of a threaded connection and presses the low pressure piston against the thrust shoulder of the rod, while a crown washer is located between the high and low pressure pistons. 5. The piston according to claim 1, characterized in that the low-pressure piston is made hollow with stiffeners. 6. The piston according to claim 1, characterized in that the low and high pressure pistons are provided with grooves for the sealing rings.

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