EP1070845A1 - Regulateur de pression de carter pour compresseur a deplacement variable - Google Patents

Regulateur de pression de carter pour compresseur a deplacement variable Download PDF

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Publication number
EP1070845A1
EP1070845A1 EP00902118A EP00902118A EP1070845A1 EP 1070845 A1 EP1070845 A1 EP 1070845A1 EP 00902118 A EP00902118 A EP 00902118A EP 00902118 A EP00902118 A EP 00902118A EP 1070845 A1 EP1070845 A1 EP 1070845A1
Authority
EP
European Patent Office
Prior art keywords
chamber
passage
pressure
valve mechanism
gas
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP00902118A
Other languages
German (de)
English (en)
Inventor
Masaki Kabushiki Kaisha Toyoda Ota
Ken Kabushiki Kaisha Toyoda SUITOU
Ryo Kabushiki Kaisha Toyoda MATSUBARA
TakuKabushiki Kaisha Toyoda ADANIYA
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toyota Industries Corp
Original Assignee
Toyoda Jidoshokki Seisakusho KK
Toyoda Automatic Loom Works Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toyoda Jidoshokki Seisakusho KK, Toyoda Automatic Loom Works Ltd filed Critical Toyoda Jidoshokki Seisakusho KK
Publication of EP1070845A1 publication Critical patent/EP1070845A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B27/00—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders
    • F04B27/08—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis
    • F04B27/14—Control
    • F04B27/16—Control of pumps with stationary cylinders
    • F04B27/18—Control of pumps with stationary cylinders by varying the relative positions of a swash plate and a cylinder block
    • F04B27/1804—Controlled by crankcase pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B27/00—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders
    • F04B27/08—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis
    • F04B27/14—Control
    • F04B27/16—Control of pumps with stationary cylinders
    • F04B27/18—Control of pumps with stationary cylinders by varying the relative positions of a swash plate and a cylinder block
    • F04B27/1804—Controlled by crankcase pressure
    • F04B2027/1809—Controlled pressure
    • F04B2027/1813—Crankcase pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B27/00—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders
    • F04B27/08—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis
    • F04B27/14—Control
    • F04B27/16—Control of pumps with stationary cylinders
    • F04B27/18—Control of pumps with stationary cylinders by varying the relative positions of a swash plate and a cylinder block
    • F04B27/1804—Controlled by crankcase pressure
    • F04B2027/1822—Valve-controlled fluid connection
    • F04B2027/1827—Valve-controlled fluid connection between crankcase and discharge chamber
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B27/00—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders
    • F04B27/08—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis
    • F04B27/14—Control
    • F04B27/16—Control of pumps with stationary cylinders
    • F04B27/18—Control of pumps with stationary cylinders by varying the relative positions of a swash plate and a cylinder block
    • F04B27/1804—Controlled by crankcase pressure
    • F04B2027/1822—Valve-controlled fluid connection
    • F04B2027/1831—Valve-controlled fluid connection between crankcase and suction chamber
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B27/00—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders
    • F04B27/08—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis
    • F04B27/14—Control
    • F04B27/16—Control of pumps with stationary cylinders
    • F04B27/18—Control of pumps with stationary cylinders by varying the relative positions of a swash plate and a cylinder block
    • F04B27/1804—Controlled by crankcase pressure
    • F04B2027/1822—Valve-controlled fluid connection
    • F04B2027/1836—Valve-controlled fluid connection between crankcase and working chamber
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B27/00—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders
    • F04B27/08—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis
    • F04B27/14—Control
    • F04B27/16—Control of pumps with stationary cylinders
    • F04B27/18—Control of pumps with stationary cylinders by varying the relative positions of a swash plate and a cylinder block
    • F04B27/1804—Controlled by crankcase pressure
    • F04B2027/184—Valve controlling parameter
    • F04B2027/1854—External parameters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B27/00—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders
    • F04B27/08—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis
    • F04B27/14—Control
    • F04B27/16—Control of pumps with stationary cylinders
    • F04B27/18—Control of pumps with stationary cylinders by varying the relative positions of a swash plate and a cylinder block
    • F04B27/1804—Controlled by crankcase pressure
    • F04B2027/1863—Controlled by crankcase pressure with an auxiliary valve, controlled by
    • F04B2027/1877—External parameters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B2205/00—Fluid parameters
    • F04B2205/15—By-passing over the pump
    • F04B2205/151—Opening width of a bypass valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B2205/00—Fluid parameters
    • F04B2205/17—Opening width of a throttling device
    • F04B2205/173—Opening width of a throttling device in a circuit

Definitions

  • the present invention relates to a crank pressure control mechanisms of a variable displacement compressors that change the inclination angle of a swash plate depending on the internal pressure of a crank chamber to change the displacement.
  • a swash plate type variable displacement compressor the inclination angle of a swash plate changes depending on the internal pressure (crank pressure Pc) of a crank chamber.
  • the displacement of the compressor is changed depending on the inclination angle of the swash plate.
  • Inlet control is one conventional method for controlling the crank pressure Pc. With inlet control, the inflow of a coolant gas from a discharge chamber to the crank chamber is controlled by an inlet control valve. In the inlet control method, the inclination of the swash plate is reduced by increasing the crank pressure Pc to lower the displacement of the compressor.
  • the closed inlet control valve when the displacement of a compressor is changed at once from maximum to minimum and is then maintained at the minimum displacement, the closed inlet control valve must be opened fully and then held fully open.
  • crank pressure Pc can become too high. In other words, the crank pressure Pc increases beyond a predetermined target value. An excessively high crank pressure Pc can cause the end faces of the pistons to strike a valve plate when the pistons reach their top dead center positions.
  • coolant gas in order to maintain the discharge displacement of a compressor at the minimum displacement, coolant gas must be supplied continuously from the discharge chamber to the crank chamber in an amount that is more than that flowing from the crank chamber through the bleed passage. This produces a flow of coolant gas from the discharge chamber, through the crank chamber, into the suction chamber, which wastes compressed coolant gas and reduces the efficiency of the compressor.
  • the inlet control valve be opened fully during the period when the crank pressure Pc increases from a low value corresponding to the maximum inclination angle position of the swash plate to a high value necessary for shifting the swash plate to the minimum inclination angle position.
  • this invention provides a variable displacement compressor for varying the displacement.
  • the compressor includes a discharge pressure zone, the pressure of which is a discharge pressure.
  • a supply passage supplies gas from the discharge pressure zone to the crank chamber.
  • An inlet valve mechanism is located in the supply passage. The inlet valve mechanism opens and closes the supply passage to control the pressure in the crank chamber.
  • An adjusting mechanism is located in the supply passage between the inlet valve mechanism and the crank chamber. The adjusting mechanism gradually varies the amount of gas that flows from the discharge pressure zone to the crank chamber through the supply passage when the inlet valve mechanism is open.
  • Figures 1-5(B) show a swash plate type variable displacement compressor having a clutch.
  • a cylinder block 1 is combined with a front housing 2 and a rear housing 4.
  • a valve plate 3 is located between the cylinder block 1 and the rear housing 4.
  • the cylinder block 1, the front housing 2, the valve plate 3 and the rear housing 4 are joined with a plurality of through bolts (not shown) to constitute a compressor housing.
  • a crank chamber 5 is defined between the cylinder block 1 and the front housing 2.
  • a drive shaft 6 is supported by the cylinder block 1 and the front housing 2 rotatable via a plurality of radial bearings.
  • a bore for containing a helical spring 7 and a rear thrust bearing 8 is formed substantially at the center of the cylinder block 1.
  • a rotating support 11 is fixed on the drive shaft 6 to rotate integrally with the drive shaft 6.
  • a front thrust bearing 9 is located between the rotating support 11 and an inner surface of the front housing 2. The drive shaft 6 is supported in the axial direction by the thrust bearings 8 and 9, which are urged forward by the spring 7.
  • the drive shaft 6 is connected via an electromagnetic clutch 40 to an engine E, which is an external drive source.
  • the electromagnetic clutch 40 includes a pulley 42, an annular solenoid coil 43 and an armature 45.
  • the pulley 42 is supported by a bearing 41 at the front end of the front housing 2.
  • the armature 45 is connected to the drive shaft 6 by a leaf spring 44.
  • a swash plate 12, or drive plate, is housed in the crank chamber 5.
  • the drive shaft 6 passes through a center hole formed in the swash plate 12.
  • the swash plate 12 is connected via a hinge mechanism 13 to the rotating support 11 and the drive shaft 6.
  • the hinge mechanism 13 consists essentially of supporting arms 14, which have guide holes, provided on the rotating support 11 and guide pins 15, which have spherical heads, provided on the front side of the swash plate 12.
  • the hinge mechanism 13 causes the swash plate 12 to rotate integrally with the drive shaft 6 and permits movement of the swash plate 12 in the axial direction of the drive shaft 6 and inclination of the swash plate 12 with respect to the axis of the drive shaft 6.
  • a helical spring 16 is fitted around the drive shaft 6 between the rotating support 11 and the swash plate 12.
  • the spring 16 urges the swash plate 12 in a direction such that the inclination angle of the swash plate 12 decreases.
  • a snap ring 17 is fixed on the drive shaft 6 between the swash plate 12 and the cylinder block 1.
  • the snap ring 17 limits rearward movement of the swash plate 12, which limits the minimum inclination angle of the swash plate 12 to, for example, three to five degrees.
  • the maximum inclination angle of the swash plate 12 is determined by the abutment of a counterweight 12a formed on the swash plate 12 against a restricting section 11a of the rotating support 11.
  • a plurality of cylinder bores 1a (only one bore 1a is shown) are defined in the cylinder block 1.
  • the cylinder bores 1a are arranged at predetermined angular intervals along a circle drawn about the axis of the drive shaft 6.
  • a single-headed piston 18 is housed in each cylinder bore 1a.
  • Each piston 18 is connected to the swash plate 12 via a pair of shoes 19.
  • a suction chamber 21 and a discharge chamber 22 are defined in the rear housing 4.
  • the valve plate 3 contains a suction port 23, a suction valve 24, a discharge port 25 and a discharge valve 26 for each cylinder bore 1a.
  • the suction chamber 21 is connected to each cylinder bore 1a via the suction port 23.
  • Each cylinder bore 1a is connected with the discharge chamber 22 via the discharge port 25.
  • the drive shaft 6 is rotated when the engine E is running, and the swash plate 12 rotates with the rotation of the shaft 6.
  • the rotational movement of the swash plate 12 is converted by the shoes 19 into reciprocating movement of the pistons 18.
  • This reciprocating movement compresses a coolant gas drawn from the suction chamber 21, through the valve plate 3, into the cylinder bore 1a.
  • the compressed coolant gas is discharged from the cylinder bore 1a into the discharge chamber 22.
  • the inclination angle of the swash plate 12 is determined by various moments acting on the swash plate 12, which include a rotational moment based on the centrifugal force of the rotating swash plate 12, a moment based on the urging force of the spring 16 and a moment based on gas pressure.
  • the moment of the rotational movement acts on the swash plate 12 to increase the inclination angle.
  • the gas pressure moment is based on the reaction force of compression acting on the pistons 18 in the compression strokes, the internal pressures of the cylinder bores 1a acting upon the pistons 18 in the suction strokes, and the internal pressure (crank pressure Pc) of the crank chamber 5.
  • the moment based on the gas pressure acts on the swash plate 12 to decrease the inclination angle.
  • the sum of the moment based on the gas pressure and the moment based on the urging force of the spring 16 becomes greater than the moment of the rotational movement when the crank pressure Pc is maintained at a relatively high level. Accordingly, the swash plate 12 shifts to the minimum inclination angle position. The sum of the moment based on the gas pressure and the moment based on the spring force is balanced with the moment of the rotational movement by adjusting the crank pressure Pc.
  • the inclination of the swash plate 12 can be set at a desired angle between the minimum inclination angle position and the maximum inclination angle position of the swash plate 12. The stroke of each piston 18, or the discharge displacement of the compressor, is also adjusted depending on the inclination angle of the swash plate 12.
  • the control mechanism for controlling the crank pressure Pc includes an inlet side/outlet side interlocking type electromagnetic valve 50, an adjusting mechanism 80 for adjusting inflow of gas, a supply passage 28, and a bleed passage 29. Both passages 28, 29 are defined in the compressor housing.
  • the supply passage 28 connects the discharge chamber 22 to the crank chamber 5.
  • An inlet valve mechanism 51 and the adjusting mechanism 80 of the electromagnetic valve 50 are located in the supply passage 28.
  • the bleed passage 29 connects the crank chamber 5 to the suction chamber 21.
  • An outlet valve mechanism 52 of the electromagnetic valve 50 is located in the bleed passage 29.
  • the discharge chamber 22 and the suction chamber 21 are connected to each other via an external coolant circuit 30.
  • the external coolant circuit 30 constitutes, together with the compressor, a cooling circuit of a vehicular air conditioner.
  • the external coolant circuit 30 is provided with a condenser 31, a thermostatic expansion valve 32 and an evaporator 33.
  • the opening size of the expansion valve 32 is feedback-controlled based on the temperature detected by a temperature detecting cylinder located at the outlet of the evaporator 33 and the evaporating pressure.
  • the outlet temperature of the evaporator 33 reflects the thermal load applied to a refrigerator circuit.
  • the expansion valve 32 supplies an appropriate amount of coolant to the evaporator 33 depending on the thermal load applied to the refrigerator circuit.
  • the flow rate of the coolant gas in the external coolant circuit 30 can be adjusted.
  • a temperature sensor 34 is located adjacent to the evaporator 33.
  • the temperature sensor 34 detects the temperature of the evaporator 33 and outputs a signal indicating the detection result to a controller C.
  • the controller C is a computer, which controls heating and cooling of the vehicle air conditioner.
  • the temperature sensor 34, a cabin temperature sensor 35 for detecting the temperature in the passenger compartment, a cabin temperature setter 36 for setting the temperature in the passenger compartment, an actuating switch 37 and an electronic control unit (ECU) are connected to the input side of the controller C.
  • a drive circuit 38 for controlling the supply of electric current to the solenoid coil 43 of the electromagnetic clutch 40 and another drive circuit 39 for controlling the supply of electric current to a coil 74 of the electromagnetic valve 50 are connected to the output side of the controller C.
  • the controller C controls the electromagnetic clutch 40 and the electromagnetic valve 50 based on various information including the temperature of the evaporator 33 detected by the temperature sensor 34, the temperature detected by the cabin temperature sensor 35, the temperature set by the cabin temperature setter 36, the ON/OFF state of the switch 37 and information from the ECU such as whether the engine E is running and engine revolution speed.
  • the electromagnetic valve 50 is provided with an inlet valve mechanism 51 for opening and closing the supply passage 28, an outlet valve mechanism 52 for opening and closing the bleed passage 29, and a solenoid 53 for driving the valve mechanisms 51 and 52.
  • the valve mechanisms 51 and 52 and the solenoid 53 are incorporated into a valve housing 54 of the electromagnetic valve 50.
  • the inlet valve mechanism 51 is provided with an inlet valve chamber 55 defined in the valve housing 54 and a valve opening 56 communicating with the valve chamber 55.
  • the inlet valve chamber 55 communicates with the discharge chamber 22 via a first port 57 and the supply passage 28.
  • the inlet valve chamber 55 is exposed to the pressure (discharge pressure Pd) of the discharge chamber 22.
  • the valve opening 56 communicates with the adjusting mechanism 80 and the crank chamber 5 via a second port 58 and the supply passage 28.
  • the first port 57, the inlet valve chamber 55, the valve opening 56 and the second port 58 form part of the supply passage 28.
  • An inlet valve body 60 is located in the inlet valve chamber 55 and is movable in the axial direction of the electromagnetic valve 50.
  • the valve element 60 moves to open and close the valve opening 56.
  • a first rod 61 and a second rod 62 extend in the axial direction of the electromagnetic valve 50 from the lower end and the upper end of the valve element 60, respectively.
  • the rods 61 and 62 pass through respective partitions in the valve housing 54.
  • the valve element 60 and the first and second rods 61 and 62 can move between an upper limit position (see Figure 2) where the valve element 60 closes the valve opening 56 and a lower limit position (see Figure 3) where the valve element 60 fully opens the valve opening 56.
  • the outlet valve mechanism 52 is provided with an outlet valve chamber 63 and a valve opening 64, which communicates with the chamber 63. Both the chamber 63 and the opening 64 are defined in the valve housing 54.
  • the valve opening 64 communicates with the crank chamber 5 via a third port 65 and the bleed passage 29.
  • the outlet valve chamber 63 communicates with the suction chamber 21 via a fourth port 66 and the bleed passage 29.
  • the pressure (suction pressure Ps) of the suction chamber 21 is applied to the outlet valve chamber 63.
  • the third port 65, the valve opening 64, the outlet valve chamber 63 and the fourth port 66 form part of the bleed passage 29.
  • An outlet valve body 67 is located in the outlet valve chamber 63 and is movable in the axial direction of the electromagnetic valve 50.
  • the valve element 67 moves in the outlet valve chamber 63 to open and close the valve opening 64. More specifically, the valve element 67 can move between an upper limit position (see Figure 2), in which the valve element 67 opens the valve opening 64, and the position illustrated in Figure 3, in which the valve element 67 closes the valve opening 64.
  • a first spring 68 is located between the outlet valve body 67 and a wall of the outlet valve chamber 63.
  • the first spring 68 urges the outlet valve body 67 in the direction to close the valve opening 64.
  • the distal end of the second rod 62 abuts against the lower surface of the outlet valve body 67.
  • the second rod 62 separates the outlet valve body 67 from the seat of the valve opening 64 against the downward urging force of the first spring 68.
  • the valve opening 64 is opened.
  • An electromagnetic actuator, or the solenoid 53 is provided with a plunger chamber 71 defined in the valve housing 54.
  • a fixed iron core 72 is located between the plunger chamber 71 and the inlet valve chamber 55.
  • the end of the first rod 61 is located in the plunger chamber 71.
  • a movable iron core 73 which serves as a plunger, and a second spring 69 are also located in the plunger chamber 71.
  • the movable iron core 73 is fixed at the distal end of the first rod 61.
  • the second spring 69 is located between the fixed iron core 72 and the movable iron core 73.
  • the second spring 69 urges the movable iron core 73, the inlet valve body 60 and the rods 61 and 62 as an integral body toward the bottom of the electromagnetic valve 50.
  • a coil 74 is wound around the valve housing 54 to surround the iron cores 72 and 73.
  • a predetermined electric current is supplied to the coil 74 from the drive circuit 39 based on a command from the controller C.
  • electric current is supplied to the coil 74, electromagnetic attraction is generated between the iron cores 72 and 73.
  • valve bodies 60 and 67 The force of the electromagnetic attraction is transmitted to the valve bodies 60 and 67 via the first and second rods 61 and 62.
  • the valve bodies 60 and 67 are moved to the positions shown in Figure 2 against the urging forces of the springs 68 and 69.
  • the inlet valve mechanism 51, outlet valve mechanism 52 and the solenoid 53 are linked with one another.
  • the valve bodies 60 and 67 of the valve mechanisms 51 and 52 move depending on the presence or absence of the supply of electric current to the coil 74. That is, when electric current is supplied to the coil 74, the inlet valve mechanism 51 is closed and the outlet valve mechanism 52 is opened, as shown in Figure 2.
  • the inlet valve mechanism 51 is opened and the outlet valve mechanism 52 is closed, as shown in Figure 3. That is, the electromagnetic valve 50 opens either the inlet valve mechanism 51 or the outlet valve mechanism 52 selectively depending on a command from an external source.
  • the crank pressure Pc can sometimes become too high.
  • the differential pressure (Pc - Ps) acting on the valve element 67 applies a force that becomes greater than the urging force of the first spring 68. If this occurs, as shown in Figure 4, the valve element 67 shifts upward against the urging force of the first spring 68 to allow gas to flow into the suction chamber 21 from the crank chamber 5 through the valve opening 64 and the outlet valve chamber 63. Since the valve element 67 is not connected to the second rod 62, the outlet valve mechanism 52 functions also as a differential pressure regulating valve for limiting the crank pressure Pc.
  • the adjusting mechanism 80 is located in a downstream part of the supply passage 28, that is, between the second port 58 and the crank chamber 5.
  • the adjusting mechanism 80 is provided with a spool valve element 83 accommodated in a storage chamber 82 defined in its housing 81.
  • the spool valve element 83 is a movable body that can reciprocate between a first stopper 91 and a second stopper 92.
  • the first and second stoppers 91,92 are provided on the inner walls of the storage chamber 82.
  • the spool valve element 83 can move between an advanced position (see Figure 5(A)) where the valve element 83 contacts the first stopper 91 and a retracted position (see Figure 5(B)) where the valve element 83 contacts the second stopper 92.
  • the storage chamber 82 is divided by the valve element 83 into an inlet chamber 84 and a pressure control chamber 85.
  • the inlet chamber 84 communicates via an inlet port 86 with the second port 58 of the inlet valve mechanism 51.
  • the inlet chamber 84 also communicates via an outlet port 87 and a first outlet passage 88 with the crank chamber 5.
  • the outlet port 87 and the first outlet passage 88 form a first passage.
  • the inlet chamber 84 and the pressure control chamber 85 communicate with each other via a first restriction 83a formed in the spool valve element 83.
  • the pressure control chamber 85 communicates via the port 89 and an second outlet passage 90 having a second restriction 90a with the crank chamber 5.
  • the size, or diameter, of the second restriction 90a is smaller than that of the first restriction 83a. Accordingly, the amount of gas passing through the second restriction 90a is less than that passing through the first restriction 83a.
  • the first restriction 83a, the pressure control chamber 85, the port 89 and the second outlet passage 90 form a second passage.
  • the pressure control chamber 85 contains a spring 93 that urges the spool valve element 83 toward the advanced position.
  • the spring 93 urges the spool valve element 83 to the advanced position, and the valve element 83 closes an outlet port 87, as shown in Figure 5(A).
  • the electromagnetic clutch 40 interrupts transmission of power from the engine E to the compressor, and the compressor is not operated. At this time, no electric current is supplied to the coil 74 of the electromagnetic valve 50. Accordingly, as shown in Figure 3, the inlet valve mechanism 51 is opened and the outlet valve mechanism 52 is closed. If the inoperative state of the compressor continues for a relatively long time, the internal pressures of the chambers 5, 21 and 22 in the compressor are equalized, and the inclination of the swash plate 12 is maintained at the minimum angle by the urging force of the spring 16.
  • the controller C outputs a command to the drive circuit 38 to supply electric current to the solenoid coil 43 of the electromagnetic clutch 40.
  • the engine E is engaged with the compressor to operate the compressor.
  • the controller C When there is a great thermal load, the pressure around the outlet of the evaporator 33 (i.e., suction pressure Ps) is high, and the difference between the temperature detected by the cabin temperature sensor 35 and the temperature set by the cabin temperature setter 36 is also great.
  • the controller C outputs a command to the drive circuit 39 to supply electric current to the coil 74 to increase the discharge capacity of the compressor. This generates electromagnetic attraction between the fixed iron core 72 and the movable iron core 73, which closes the inlet valve mechanism 51 and opens the outlet valve mechanism 52, as shown in Figure 2.
  • the supply of gas from the discharge chamber 22 to the crank chamber 5 is interrupted, and the crank chamber 5 and the suction chamber 21 communicate with each other.
  • crank pressure Pc drops to about the suction pressure Ps, which reduces the moment based on gas pressure acting upon the swash plate 12. Consequently, the inclination of the swash plate 12 increases to the maximum inclination angle, which increases the displacement of the compressor to the maximum.
  • the controller C When the increase in the discharge displacement of the compressor reduces the thermal load (or when the pressure Ps around the outlet of the evaporator 33 is lowered), the difference between the temperature detected by the cabin temperature sensor 35 and the temperature set by the cabin temperature setter 36 becomes small. At this time, the controller C outputs a command to the drive circuit 39 to interrupt the supply of electric current to the coil 74 to lower the discharge performance of the compressor. Thus, as shown in Figure 3, the inlet valve mechanism 51 is opened and outlet valve mechanism 52 is closed.
  • the internal pressure of the inlet chamber 84 and that of the pressure control chamber 85 become equal to the discharge pressure Pd due to the flow of gas front the inlet chamber 84 through the first restriction 83a into the pressure control chamber 85.
  • the differential pressure between the chamber 84 and the chamber 85 becomes smaller.
  • the spring 93 urges the spool valve element 83 to move from the retracted position to the advanced position to close the outlet port 87.
  • the outlet port 87 is opened only the while the spool valve element 83 moves from the advanced position to the retracted position and back to the advanced position.
  • the adjusting mechanism 80 increases the amount of gas supplied from the discharge chamber 22 to the crank chamber 5 only while the spool valve element 83 moves back and forth a time.
  • the period during which the spool valve element 83 moves from the advanced position to the retracted position and back to the advanced position, or the period during which the outlet port 87 is opened, is determined mainly by the volume of the pressure control chamber 85 and the difference in the flow rate of gas passing through the two restrictions 83a and 90a.
  • the outlet valve mechanism 52 As long as the outlet valve mechanism 52 remains closed, the swash plate 12 maintains the minimum inclination angle.
  • gas having a pressure that is approximately equal to the discharge pressure Pd is supplied little by little from the pressure control chamber 85, which is exposed to the discharge pressure Pd, to the crank chamber 5 through the second restriction 90a. This gas makes up for the inevitable loss in the crank pressure Pc and is merely to maintain the crank pressure Pc in the current high-pressure state. If the crank pressure Pc is too high, the outlet valve mechanism 52 functions as a differential pressure regulating valve as described above with reference to Figure 4, to temporarily release gas from the crank chamber 5 to limit the crank pressure Pc.
  • the controller C resumes the supply of electric current to the coil 74.
  • the inlet valve mechanism 51 and the outlet valve mechanism 52 are closed and opened respectively to increase the inclination angle or the swash plate 12.
  • gas escapes from the inlet chamber 84 and the pressure control chamber 85 in the adjusting mechanism 80 only through the restrictions 83a and 90a into the crank chamber 5. Accordingly, the internal pressures of these chambers 84 and 85 fall gradually from the discharge pressure Pd toward the crank pressure Pc.
  • the controller C interrupts the supply of electric current to the solenoid coil 43.
  • a predetermined level or lower a temperature at which frosting can occur in the evaporator 33
  • This embodiment has the following effects.
  • the inlet valve mechanism 51 of the electromagnetic valve 50 is fully closed to avoid the flow of gas from the discharge chamber 22 to the crank chamber 5. Accordingly, the gas discharged into the discharge chamber 22 is almost entirely supplied to the external coolant circuit 30, allowing the compressor to operate efficiently.
  • the spool valve element 83 of the adjusting mechanism 80 moves to the retracted position practically simultaneously with the opening of the inlet valve mechanism 51 of the electromagnetic valve 50 to open the outlet port 87 and the first outlet passage 88.
  • the flow rate of gas from the discharge chamber 22 to the crank chamber 5 is great to rapidly increase the crank pressure Pc. This results in a rapid shift to the minimum discharge displacement and improves the compressor's response to a demand for a change in the displacement.
  • the outlet port 87 and the first outlet passage 88 of the adjusting mechanism 80 are opened only the while the spool valve element 83 moves back and forth a time. This temporary opening feeds a minimum amount of gas to the crank chamber 5 needed to fully increase the crank pressure Pc. That is, excessive delivery of the high-pressure gas to the crank chamber 5 is prevented, and the release of gas from the discharge chamber 22 is thus minimized. Accordingly, the compressor has superior operation efficiency compared to prior art compressors.
  • the adjusting mechanism 80 can repeat the operation of automatically supplying gas to the crank chamber 5 any number of times even when the opening and closing of the inlet valve mechanism 51 is repeated in short cycles. Accordingly, even when abrupt changes in the thermal load are repeated, the compressor does not lose control of the discharge displacement. That is, the compressor operates properly under any circumstances.
  • the valve body 67 of the outlet valve mechanism 52 can be separated from the second rod 62. Accordingly, when the crank pressure Pc becomes too high, the outlet valve mechanism 52 serves as a differential pressure regulating valve operating independent from the operation of the inlet valve mechanism 51, as shown in Figure 4. Thus, it is guaranteed that the crank pressure Pc will not become too high.
  • Figures 6 and 7 show an electromagnetic valve 50 in a second embodiment of the present invention. The differences from the first embodiment shown in Figures 1 to 5(B) will mainly be described.
  • the adjusting mechanism 80 is incorporated into the valve housing 54 of the electromagnetic valve 50 in this embodiment. More specifically, a chamber for the adjusting mechanism 80 is defined above the inlet valve mechanism 51, and the spool valve element 83 is housed in this chamber to move in the axial direction of the electromagnetic valve 50.
  • the second rod 62 passes through the spool valve element 83 and is movable relative to the valve element 83.
  • the inlet chamber 84 is defined under the spool valve element 83.
  • the inlet chamber 84 communicates with the inlet valve chamber 55 via a valve opening 56.
  • the inlet chamber 84 communicates with the crank chamber 5 via an outlet port 87 (corresponding to the port 58 in Figure 2) located in the valve housing 54.
  • a pressure control chamber 85 is defined above the spool valve element 83.
  • the pressure control chamber 85 communicates with the crank chamber 5 via a restriction 90a connecting the pressure control chamber 85 to the valve opening 64, and a third port 65.
  • a spring 93 is housed in the pressure control chamber 85.
  • the chambers 84 and 85 communicate with each other via a first restriction 83a (having a diameter greater than that of the restriction 90a) defined in the spool valve element 83.
  • a first restriction 83a having a diameter greater than that of the restriction 90a
  • the outlet port 87 is closed.
  • the spool valve element 83 is located at the retracted position (see Figure 7) and is abutted against a second stopper 92, the outlet port 87 is opened.
  • the downstream part of the supply passage 28 serves also as the first outlet passage 88 of Figures 5(A) and 5(B).
  • a communication hole may be defined in the housing wall partitioning the pressure control chamber 85 to provide an auxiliary chamber of the pressure control chamber 85 within the compressor.
  • the second spring 69 is housed in the plunger chamber 71 in Figures 2, 3, 6 and 7, the second spring 69 may be housed in the inlet valve chamber 55, as shown in Figure 8.
  • the electromagnetic valve 50 having the inlet valve mechanism 51 and the outlet valve mechanism 52 shown in Figures 1 to 8 may be replaced with an electromagnetic valve having no outlet valve mechanism 52 but having an inlet valve mechanism 51 and a solenoid 53.
  • a fixed restriction 100 is preferably located in the bleed passage 29 connecting the crank chamber 5 and the suction chamber 21.
  • the diameter of the fixed restriction 100 may be set to satisfy the following equations: fC ⁇ fA + fB , when the inlet valve mechanism 51 is opened, and fC > fA, when the inlet valve mechanism 51 is closed.
  • the present invention may be applied to a variable displacement compressor of the clutchless type, in which power is always transmitted from the external drive source E directly to the drive shaft 6.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
  • Control Of Positive-Displacement Pumps (AREA)
EP00902118A 1999-02-10 2000-02-07 Regulateur de pression de carter pour compresseur a deplacement variable Withdrawn EP1070845A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP11032895A JP2000230481A (ja) 1999-02-10 1999-02-10 容量可変型圧縮機のクランク圧制御機構
JP3289599 1999-02-10
PCT/JP2000/000650 WO2000047896A1 (fr) 1999-02-10 2000-02-07 Regulateur de pression de carter pour compresseur a deplacement variable

Publications (1)

Publication Number Publication Date
EP1070845A1 true EP1070845A1 (fr) 2001-01-24

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Application Number Title Priority Date Filing Date
EP00902118A Withdrawn EP1070845A1 (fr) 1999-02-10 2000-02-07 Regulateur de pression de carter pour compresseur a deplacement variable

Country Status (3)

Country Link
EP (1) EP1070845A1 (fr)
JP (1) JP2000230481A (fr)
WO (1) WO2000047896A1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1336757A2 (fr) * 2002-02-18 2003-08-20 Kabushiki Kaisha Toyota Jidoshokki Système de contrôle pour compresseur à plateau en biais
EP1363023A2 (fr) * 2002-05-13 2003-11-19 TGK CO., Ltd. Soupape de contrôle pour un compresseur à capacité variable
EP1369583A2 (fr) * 2002-06-04 2003-12-10 TGK CO., Ltd. Soupape de commande pour un compresseur à capacité variable
US6729853B2 (en) 2001-09-05 2004-05-04 Kabushiki Kaisha Toyota Jidoshokki Displacement control device for variable displacement compressor
WO2006079525A1 (fr) * 2005-01-25 2006-08-03 Valeo Compressor Europe Gmbh Compresseur a piston axial
WO2018186033A1 (fr) * 2017-04-06 2018-10-11 サンデン・オートモーティブコンポーネント株式会社 Compresseur à déplacement variable

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4195633B2 (ja) * 2002-04-25 2008-12-10 サンデン株式会社 容量制御弁を有する可変容量圧縮機
JP4130566B2 (ja) * 2002-09-25 2008-08-06 株式会社テージーケー 可変容量圧縮機用容量制御弁

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Publication number Priority date Publication date Assignee Title
JP2508082B2 (ja) * 1987-05-16 1996-06-19 株式会社豊田自動織機製作所 可変容量圧縮機
JP2765057B2 (ja) * 1989-06-05 1998-06-11 株式会社豊田自動織機製作所 可変容量圧縮機

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0047896A1 *

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6729853B2 (en) 2001-09-05 2004-05-04 Kabushiki Kaisha Toyota Jidoshokki Displacement control device for variable displacement compressor
EP1336757A2 (fr) * 2002-02-18 2003-08-20 Kabushiki Kaisha Toyota Jidoshokki Système de contrôle pour compresseur à plateau en biais
EP1336757A3 (fr) * 2002-02-18 2003-12-03 Kabushiki Kaisha Toyota Jidoshokki Système de contrôle pour compresseur à plateau en biais
US6733246B2 (en) 2002-02-18 2004-05-11 Kabushiki Kaisha Toyota Jidoshokki Control device for variable displacement type compressor
EP1363023A2 (fr) * 2002-05-13 2003-11-19 TGK CO., Ltd. Soupape de contrôle pour un compresseur à capacité variable
EP1363023A3 (fr) * 2002-05-13 2006-10-04 TGK CO., Ltd. Soupape de contrôle pour un compresseur à capacité variable
EP1369583A2 (fr) * 2002-06-04 2003-12-10 TGK CO., Ltd. Soupape de commande pour un compresseur à capacité variable
EP1369583A3 (fr) * 2002-06-04 2006-10-11 TGK CO., Ltd. Soupape de commande pour un compresseur à capacité variable
WO2006079525A1 (fr) * 2005-01-25 2006-08-03 Valeo Compressor Europe Gmbh Compresseur a piston axial
WO2018186033A1 (fr) * 2017-04-06 2018-10-11 サンデン・オートモーティブコンポーネント株式会社 Compresseur à déplacement variable
CN110418889A (zh) * 2017-04-06 2019-11-05 三电汽车部件株式会社 可变容量压缩机
US11098703B2 (en) 2017-04-06 2021-08-24 Sanden Automotive Components Corporation Variable displacement compressor with variation in discharge capacity

Also Published As

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WO2000047896A1 (fr) 2000-08-17
JP2000230481A (ja) 2000-08-22

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