Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
  • F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
  • F04C18/30—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members
  • F04C18/32—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having both the movement defined in group F04C18/02 and relative reciprocation between the co-operating members
  • F04C18/322—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having both the movement defined in group F04C18/02 and relative reciprocation between the co-operating members with vanes hinged to the outer member and reciprocating with respect to the outer member
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
  • F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
  • F04C29/0042—Driving elements, brakes, couplings, transmissions specially adapted for pumps
  • F04C29/005—Means for transmitting movement from the prime mover to driven parts of the pump, e.g. clutches, couplings, transmissions
  • F04C29/0057—Means for transmitting movement from the prime mover to driven parts of the pump, e.g. clutches, couplings, transmissions for eccentric movement
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
  • F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
  • F04C29/0042—Driving elements, brakes, couplings, transmissions specially adapted for pumps
  • F04C29/005—Means for transmitting movement from the prime mover to driven parts of the pump, e.g. clutches, couplings, transmissions
  • F04C29/0071—Couplings between rotors and input or output shafts acting by interengaging or mating parts, i.e. positive coupling of rotor and shaft
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
  • F04C2240/00—Components
  • F04C2240/60—Shafts

Definitions

• the invention relates to a fluid compressor, in particular for a thermoregulation circuit such as an air conditioning circuit of a motor vehicle.
• a roll compressor or rolling piston compressor, is a type of compressor used in temperature control circuits, such as heating, ventilation, and/or air conditioning systems. Unlike traditional compressors that use pistons or screw gears to compress the refrigerant, a roll compressor uses a movable cylindrical piston that is mounted to roll eccentrically within a cylindrical stator.
• the stator is the fixed part of the roll compressor that surrounds the cylindrical piston. It has a cylindrical wall, hereafter referred to as the cylinder, oriented along a first axis, on which the piston rolls, and which together form two compression chambers where the fluid is compressed successively.
• the two fluid compression chambers have a variable volume, determined by the position of an interface zone between the rolling piston and the cylinder; this interface zone is movable with the rolling piston.
• the invention satisfies this need by proposing a fluid compressor comprising a means for increasing the contact pressure between the piston and the cylinder.
• the interface zone 20 delimits in the cylinder 12 two fluid compression chambers, respectively downstream compression chamber 24 and upstream compression chamber 22.
• the compressor 10 further comprises an inlet port 26 and a discharge port 28 which are separated by a sliding tab 30 which is elastically and tightly returned to contact with the external surface of the piston 16.
• piston 16 rotates clockwise.
• the fluid to be compressed is introduced through the inlet port 26 and then confined upstream of the interface zone 20 by the piston 16 between the piston 16 and the wall 18 of the cylinder 12 in one of the chambers, namely the upstream chamber 22.
• the other chamber namely the downstream chamber 24, it is pushed back and simultaneously compressed towards the discharge port 28 through which it is discharged from the compressor 10 under high pressure.
• the contact pressure exerted by the piston 16 on the wall 18 is directly determined by the geometry of the piston 16, the wall 18, and the offset between the axes A and B of the piston 16.
• the contact pressure is likely to be reduced during operation as the piston 16 moves and the volume of the downstream compression chamber 24 decreases, due to the establishment of an increasing pressure in this downstream compression chamber 24 exerted on the piston 16.
• the resulting force P of the pressure exerted on the cylinder 16 tends to create micro-leaks of fluid between the downstream compression chamber 24 and the upstream compression chamber 22, risking causing the piston to slightly lift due to the assembly clearances necessarily present.
• the invention remedies this drawback by proposing a compressor 10 equipped with a means 54 for stressing the piston 16 towards the interface zone 20 in order to maintain, or even increase, the contact pressure exerted by the piston 16 on the wall 18 against the pressure P exerted on the piston 16 by the differential of fluid pressure between the two chambers 22, 24.
• the piston arousal means 54 acts by reaction on the shaft 14 to generate a contact force FR of the piston 16 with the cylinder 16 at the interface zone 20.
• the invention applies in particular to a piston 16 drive configuration by shaft 14, according to which the piston 16 is supported by a bearing 32.
• the bearing 32 comprises an inner ring 34 and an outer ring 36.
• the piston 16 has a bore 38 receiving the outer ring 36 of the bearing 32, mounted to rotate relative to the inner ring 34.
• the bearing 32 comprises a ball bearing 40, or a roller bearing, but it could be another type of bearing.
• the ring 34 has a bore 42, eccentric with respect to the second axis B of the ring. This bore 42 is received on the drive shaft 14.
• the inner ring 34 is rotationally linked to the shaft 14 by a drive finger 44.
• the drive finger 44 is formed at the end of a key 50, which is received without play in a slot 52 formed in the drive shaft 14.
• the stressing means 54 is suitable for stressing the piston 16 in a stressing direction which is perpendicular to the first and second axes A, B, i.e. in the plane of figures 4 to 6. In the present case, and without limiting the invention, this stressing direction corresponds to the radial direction R.
• the stressing means 54 is interposed between the drive shaft 14 and the inner ring 34 of the bearing.
• the stressing means 54 can be made in different ways, for example by an elastic means with radial effect interposed between the drive shaft 14 and the inner ring 34 of the bearing.
• the actuation means 54 is arranged by cooperation between the drive finger 44 and the notch 48.
• the notch 48 has a first edge 46 oriented along the direction R and a second opposite edge 46', which is inclined with respect to the direction R to form said means 54, said second inclined edge 46' being able to transform any stress F exerted by the drive finger 44 perpendicular to said second inclined edge 46' into a drive stress F exerted on the ring 46 along a direction X which is not strictly tangential, which would be the case if the edges 46, 46' were parallel.
• the force F is decomposed into a tangential component F ⁇ sub> T ⁇ /sub> and at least one component F ⁇ sub>R ⁇ /sub> acting along the direction R of the force.
• the force exerted on the finger 44 on the edge 46' is necessarily perpendicular to this edge 46', which is itself inclined. Consequently, the inclination of the edge 46' induces a radial component F ⁇ sub> R ⁇ /sub> of the force F.
• this component is transmitted to the piston 16.
• the second inclined edge 46' forms an angle of approximately 30 to 60 degrees with the first edge 46.
• the drive of the piston 16 by the shaft 14 generates, particularly dynamically once the drive is effective and the shaft 14 drives the ring 34, an additional radial force FR beyond that obtained by simply offsetting the axes.
• This force FR increases the contact pressure between the piston 16 and the cylinder 12, thereby improving the seal in the interface zone 20 between the piston 16 and the cylinder 12 and, consequently, increasing the compressor's performance.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Applications Or Details Of Rotary Compressors (AREA)
• Compressors, Vaccum Pumps And Other Relevant Systems (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=93011083

Family Applications (1)

Country Status (2)

Citations (4)

• 2024
  • 2024-07-22 FR FR2408049A patent/FR3164737A1/fr active Pending
• 2025
  • 2025-07-22 EP EP25190841.4A patent/EP4685352A1/de active Pending

Patent Citations (4)

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