Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
  • F16K17/00—Safety valves; Equalising valves, e.g. pressure relief valves
  • F16K17/003—Safety valves; Equalising valves, e.g. pressure relief valves reacting to pressure and temperature
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
  • F25B41/00—Fluid-circulation arrangements
  • F25B41/20—Disposition of valves, e.g. of on-off valves or flow control valves
  • F25B41/24—Arrangement of shut-off valves for disconnecting a part of the refrigerant cycle, e.g. an outdoor part

Definitions

• the present invention relates to a pressure control valve for controlling refrigerant pressure in a re ⁇ frigerating system or a heat-pump system.
• the pressure control valve is intended to be connected to the high pressure side of the system and functions to counteract the throughflow of refrigerant until a sufficiently high pressure has been obtained in the system.
• the oil is circulated with the aid of the pressure difference that prevails between the oil separator on the outlet side of the compressor, i.e. the compressor outlet pressure, and the inter ⁇ mediate pressure in the compressor compression chamber, to which the oil is recycled.
• an external oil pump is coupled to the system in order to ensure a sufficient flow of oil.
• a pressure control valve or pressure holding valve, has been connected to the high pressure side of a refrigerating system or a heat-pump system, for the purpose of controlling the pressure level of a re ⁇ frigerant on said high pressure side.
• This pressure control valve includes a valve housing which houses a valve body and a valve seat, and the valve is essen ⁇ tially and primarily spring balanced and will not open to allow gaseous refrigerant to pass therethrough until the pressure of said gaseous refrigerant has reached a determined level.
• the valve opens, the through- flowing gaseous refrigerant is able to act on one side of a servopiston in a servocylinder, via a throughflow passage in the pressure control valve.
• the piston rod of the piston is connected to the valve body of the valve.
• the other side of the piston is influenced by an intermediate pressure or low pressure from the refri ⁇ gerating system or heat-pump system. Depending on the pressure difference across the piston, this will have a secondary influence on the valve body of said pressure control valve, such as to hold the valve body in its valve open position.
• the pressure control valve will open subsequent to starting the compressor and will subsequently deliver gaseous refrigerant of sufficiently high pressure to the sys ⁇ tem.
• the valve then remains open for as long as the gaseous refrigerant on the high pressure side of the system has the aforesaid high pressure.
• the valve will close immediate ⁇ ly and therewith interrupt the supply of gaseous re ⁇ frigerant, due to the spring action on the valve body and due also to an insufficient pressure difference across the piston of the servodevice.
• Figure 1 illustrates a closed pressure control valve constructed in accordance with the invention
• Figure 2 illustrates the valve when open.
• the drawings illustrate the construction of an inven ⁇ tive pressure control valve.
• the valve comprises a valve housing 1 which houses a valve seat 2 and a valve body 3.
• the valve seat 2 has a substantially circular shape and is connected to a vertical connector part 4 through which gaseous refrigerant enters from a high pressure side/refrigerating compressor in a refrigerat ⁇ ing system or heat-pump system.
• the valve body 3 has the form of a substantially circular disc which is vertically moveable in relation to the valve set 2.
• a spring 5 is mounted between the valve body 3 and a servocylinder device 6 in the valve housing 1 and acts in a valve closing direction.
• the cylinder 6 has moun- ted therein a piston 7 and a piston rod 8, or some like device, which may be deta ⁇ hably connected to the valve body 3.
• the spring 5 may surround the piston rod 8.
• the working direction of the piston 7/piston rod 8 coin ⁇ cides with the valve-body action line.
• a throughflow passage 9 connects the internal throughflow space 10 of the valve housing 1 with one internal part-chamber 11 in the servocylinder, this part-chamber being defined by the inner wall of the cylinder 6 and one end surface and the end surface of the piston 7, discounting the cross-section surface of the piston rod 8.
• the other part-chamber 12 of the cylinder is defined by the inner wall of the cylinder 6 and one end surface and the end surface of the piston 7.
• the second part-chamber 12 is connected to a passage 13 which extends to a connector part 14 in a cylinder closure member 15.
• a screw 16 Arranged in the closure member 15 is a screw 16 which functions to positively or forcibly close the valve. Subsequent to removing a protective part 17 or the like, the screw 16 can be screwed down into or up out of the cylinder 6, with the aid of a spanner or like tool.
• the piston is forced downwards in the cylinder 6, wherewith the valve body 3 connected to the piston rod 8 can be forced down against the valve seat 2 therewith to close and shut-off the pressure control valve.
• the valve opening pressure can be varied, by using springs of different spring characteristics and/or different spring forces.
• the valve When using the valve in a refrigerating system or heat- pump system, the valve is fitted in a connection line on the high pressure side of the system, between, for example, a refrigerating compressor and a condenser function incorporated in the system.
• the pressure will rise in the connection line upstream of the control valve.
• the valve body 3 is held in its valve closed position, see Figure 1, until the spring force and the possibly occurrent resultant force across the servopiston are together greater than the pressure prevailing in the connector part 4.
• the spring 5 constantly urges the valve body 3 in its valve closing direction, such as to shut-off through ⁇ flow 18.
• the pressure difference across the piston 7 counteracts the force exerted by the spring 5.
• the pressure control valve is closed when a given first lowest pressure difference prevails across the piston 7.
• a given second lowest pressure-difference is reached between the pressure area of the valve body 3 and the control-pressure area of the piston 7 which is greater than the spring pressure and results in an upwardly acting force on the valve body, the valve will begin to open.
• the valve is held fully open when there is reached a given third lowest pressure-difference which is greater than said second lowest pressure- difference.
• valve will open at a given predetermined pressure and allow gaseous refrigerant to flow there ⁇ through, wherein the pressure exerted by the re- frigerant also acts on the undersurface of the piston
• the other side of the piston is constantly under the influence of an inter ⁇ mediate pressure or a low pressure.
• the pressure difference across the piston 7 will be capable of lifting and holding the piston with the piston rod counteracted by the spring force, in spite of the area difference, and therewith of holding the valve body, which is connected to the piston rod, in a raised position and away from the valve seat, thereby enabling the flow of gaseous refrigerant through the valve to be maintained. If the pressure should fall beneath a given predetermined level, the pressure control valve will therewith close immediately and prevent the throughflow of refrigerant.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Safety Valves (AREA)
• Temperature-Responsive Valves (AREA)
• Fluid-Driven Valves (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=20379002

Family Applications (1)

Country Status (4)

Families Citing this family (3)

Family Cites Families (8)

• 1990
  • 1990-03-27 SE SE9001104A patent/SE467708B/sv not_active IP Right Cessation
• 1991
  • 1991-03-27 WO PCT/SE1991/000234 patent/WO1991014907A1/en not_active Application Discontinuation
  • 1991-03-27 EP EP91907055A patent/EP0551267A1/de not_active Withdrawn
  • 1991-03-27 AU AU75844/91A patent/AU7584491A/en not_active Abandoned

Non-Patent Citations (1)

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