Patent Description:
A variable displacement compressor used for an air conditioning system of an automobile, etc. includes a rotating shaft to be driven and rotated by an engine, a swash plate coupled to the rotating shaft in such a manner that a tilt angle is variable, compressing pistons coupled to the swash plate, etc., and by changing the tilt angle of the swash plate, changes a stroke amount of the pistons to control a discharge amount of a fluid. This tilt angle of the swash plate can be continuously changed by appropriately controlling pressure in a control chamber while utilizing a suction pressure Ps of a suction chamber that suctions the fluid, a discharge pressure Pd of a discharge chamber that discharges the fluid pressurized by the pistons, and a control pressure Pc of the control chamber that houses the swash plate, by means of a capacity control valve to be driven to open and close by electromagnetic force.

At the time of continuously driving the variable displacement compressor, the capacity control valve performs normal control in which energization is controlled by a control computer, a valve body is moved in an axial direction by electromagnetic force generated in a solenoid, and a CS valve provided between a control port through which a control fluid of the control pressure Pc passes and a suction port through which a suction fluid of the suction pressure Ps passes is opened and closed to adjust the control pressure Pc of the control chamber of the variable displacement compressor.

For example, the capacity control valve shown in Patent Citations <NUM> and <NUM> mainly includes a valve housing including a Pc port through which the control fluid passes and a Ps port through which the suction fluid passes, and the CS valve that can switch the state of communication between the Pc port and the Ps port, and opens and closes the CS valve to adjust the control pressure Pc. The CS valve includes a CS valve body that is driven in the axial direction by the solenoid, and a CS valve seat which is provided between the Pc port and the Ps port and with which the CS valve body can come into contact, and performs control to bring the CS valve into a closed state so that the control pressure Pc is increased, or bring the CS valve into an open state so that the control pressure Pc is lowered.

By the way, in the air conditioning system, prompt temperature control is required, and there is a potential demand such as wanting to change the flow rate or pressure of a refrigerant to be supplied from the variable displacement compressor in a short time. However, since the capacity control valve of Patent Citations <NUM> and <NUM> has a structure in which the CS valve body is directly driven by driving force of the solenoid, in order to increase the flow rate of the refrigerant controlled by the capacity control valve, it is necessary to enlarge the solenoid, the valve body, the valve opening diameter, etc. Thus, energy efficiency deteriorates and it is difficult for the energy efficiency to coexist with reducing the size of the capacity control valve itself.

The present invention has been made in light of such a problem, and an object of the present invention is to provide a capacity control valve having excellent energy efficiency and a large capacity.

In order to solve the above problem, a capacity control valve according to the present invention includes: a valve housing to which a suction fluid having a suction pressure and a control fluid having a control pressure are supplied; a solenoid; a CS valve formed of a CS valve body that partitions an inside of the valve housing into a first space and a second space and moves according to the suction pressure of the suction fluid and the control pressure of the control fluid, and a CS valve seat with which the CS valve body is configured to come into contact; a biasing member that biases the CS valve body in a valve opening direction of the CS valve; and a pilot valve formed of a pilot valve body to be driven by the solenoid and a pilot valve seat with which the pilot valve body is configured to come into contact. The control fluid flows into the first space, the suction fluid is flowable into the second space via an orifice, and the control fluid is introduced into the other space by the pilot valve. According to the aforesaid feature of the present invention, when the pilot valve to be driven by the solenoid is opened, the pressure of the other space is raised, and a differential pressure applied to the CS valve body reaches a predetermined value or less, the CS valve can be opened. Therefore, the driving electric power of the solenoid can be reduced, and the valve opening degree of the CS valve can be increased.

It may be preferable that the orifice discharges a fluid of the second space toward a suction chamber in which an external suction fluid is housed. According to this preferable configuration, the fluid can be circulated in a closed system.

It may be preferable that an opening degree of the pilot valve is adjustable. According to this preferable configuration, since the pressure of the fluid of the other space is adjustable, the opening degree of the CS valve is adjustable.

It may be preferable that the CS valve body includes a hollow cylindrical body with an outer flange, and the outer flange slides on an inner peripheral surface of the valve housing. According to this preferable configuration, since the suction fluid can be kept in a sealed state by the CS valve body, the capacity control valve can be compactly configured.

It may be preferable that the CS valve body slides on an outer peripheral surface of a guide member into which the pilot valve body is inserted. According to this preferable configuration, since the suction fluid can be kept in a sealed state by the CS valve body, the capacity control valve can be compactly configured.

It may be preferable that an elastic seal member is disposed between an inner peripheral surface of the CS valve body and the outer peripheral surface of the guide member. According to this preferable configuration, control fluid sealing performance is excellent.

It may be preferable that a complementary step is formed in an inner peripheral surface of the CS valve body and the outer peripheral surface of the guide member. According to this preferable configuration, control fluid sealing performance is excellent.

It may be preferable that the orifice is be provided in the valve housing. According to this preferable configuration, the capacity control valve can be compactly configured.

It may be preferable that the pilot valve seat is formed in the first space. According to this preferable that, since a part of the pilot valve body is disposed in the first space, and the pressure of the first space is applied to the pilot valve body in a direction in which the pilot valve is closed, there is little risk that the pilot valve is opened when the solenoid is not energized.

It may be preferable that the CS valve seat is formed of an elastic body. According to this preferable configuration, the CS valve can be reliably closed.

It may be preferable that the biasing member is disposed in the second space. According to this preferable configuration, since the biasing member can be disposed using the space into which the suction fluid flows, the capacity control valve can be compactly configured.

It may be preferable that the CS valve body includes, in addition to the hollow cylindrical body with the outer flange, a ring that is externally inserted and fixed to the hollow cylindrical body in an airtight manner and that is provided with an abutting portion configured to abut the CS valve seat. According to this preferable configuration, the CS valve can be easily assembled while securing a large flow rate in the CS valve.

Modes for implementing a capacity control valve according to the present invention will be described below based on embodiments.

A capacity control valve according to a first embodiment of the present invention will be described with reference to <FIG>. Hereinafter, a description will be given based on the assumption that the right and left sides when seen from the front side of <FIG> are right and left sides of the capacity control valve. In detail, a description will be given based on the assumption that the left side of drawing sheets on which a valve housing <NUM> is disposed is a left side of the capacity control valve and the right side of the drawing sheets on which a solenoid <NUM> is disposed is a right side of the capacity control valve.

A capacity control valve V of the present invention is assembled into a variable displacement compressor (not shown) used for an air conditioning system of an automobile, etc., and by variably controlling the pressure of a working fluid (hereinafter, simply referred to as a "fluid") which is a refrigerant, controls the discharge amount of the variable displacement compressor to adjust the air conditioning system to a desired cooling ability.

First, the variable displacement compressor will be described. The variable displacement compressor includes a casing including a discharge chamber, a suction chamber, a control chamber, and a plurality of cylinders. Incidentally, the variable displacement compressor is provided with a communication passage that allows direct communication between the discharge chamber and the control chamber, and the communication passage is provided with a fixed orifice <NUM> that adjusts and balances the pressures of the discharge chamber and the control chamber (refer to <FIG>).

In addition, the variable displacement compressor includes a rotating shaft to be driven and rotated by an engine (not shown) installed outside the casing; a swash plate coupled to the rotating shaft so as to be tiltable by a hinge mechanism in the control chamber; and a plurality of pistons coupled to the swash plate and reciprocatably fitted in the respective cylinders. The tilt angle of the swash plate is continuously changed by appropriately controlling pressure in the control chamber while utilizing a suction pressure Ps of the suction chamber that suctions the fluid, a discharge pressure Pd of the discharge chamber that discharges the fluid pressurized by the pistons, and a control pressure Pc of the control chamber that houses the swash plate, by means of the capacity control valve V to be driven to open and close by electromagnetic force. Thereby, the stroke amount of the pistons is changed to control the discharge amount of the fluid.

As shown in <FIG>, in the capacity control valve V assembled into the variable displacement compressor, electric current which energizes a coil <NUM> forming the solenoid <NUM> is adjusted, opening and closing control of a pilot valve <NUM> in the capacity control valve V is performed, the differential pressure applied to a CS valve body reaches a predetermined value or less, and the opening degree of a CS valve <NUM> is adjusted, and thereby the fluid flowing out from the control chamber to the suction chamber is controlled, so that the control pressure Pc in the control chamber is variably controlled. Incidentally, the control pressure Pc in the control chamber can be raised by always supplying a discharge fluid of the discharge pressure Pd of the discharge chamber to the control chamber via the fixed orifice <NUM> and closing the CS valve <NUM> in the capacity control valve V.

In the present embodiment, the CS valve body includes a hollow cylindrical body <NUM> with an outer flange (hereinafter, simply referred to as a hollow cylindrical body <NUM>), and a ring <NUM> that is externally inserted and integrally fixed to an axially left end portion of the hollow cylindrical body <NUM> in an airtight manner. The CS valve <NUM> is formed of the ring <NUM> forming the CS valve body and a CS valve seat 10a formed at an opening end edge on an axially left side of the valve housing <NUM>. A tapered abutting portion 54a formed at an axially right end of the ring <NUM> comes into contact with and separates from the CS valve seat 10a to open and close the CS valve <NUM>. The pilot valve <NUM> is formed of a rod <NUM> serving as a pilot valve body and a pilot valve seat 82a formed at an axially left end of a center post <NUM> serving as a guide member. An abutting portion 53a formed in an axially left end portion of the rod <NUM> comes into contact with and separates from the pilot valve seat 82a to open and close the pilot valve <NUM>.

Next, a structure of the capacity control valve V will be described. As shown in <FIG>, the capacity control valve V mainly includes the valve housing <NUM> made of a metallic material or a resin material; a hollow cylindrical body <NUM>, the ring <NUM>, the rod <NUM> disposed in the valve housing <NUM> so as to be reciprocatable in an axial direction; and the solenoid <NUM> that is connected to the valve housing <NUM> and exerts driving force on the rod <NUM>. Incidentally, in the present embodiment, the rod <NUM> forms a part of the solenoid <NUM>.

As shown in <FIG>, the solenoid <NUM> mainly includes a casing <NUM> including an opening portion 81a that is open to the left in the axial direction; a center post <NUM> that has a substantially cylindrical shape and is inserted into the opening portion 81a of the casing <NUM> from the left in the axial direction and fixed on a radially inner side of the casing <NUM>; the rod <NUM> which is inserted into the center post <NUM> and reciprocatable in the axial direction and in which the abutting portion 53a formed in the axially left end portion of the rod <NUM> is disposed on the left in the axial direction of the pilot valve seat 82a; a movable iron core <NUM> to which an axially right end portion of the rod <NUM> is inserted and fixed; a coil spring <NUM> provided between the center post <NUM> and the movable iron core <NUM> to bias the movable iron core <NUM> to the right in the axial direction which is a valve closing direction of the pilot valve <NUM>; and the coil <NUM> for excitation wound on an outer side of the center post <NUM> via a bobbin.

A recessed portion 81b in which a radially inner side of an axially left end is recessed to the right in the axial direction is formed in the casing <NUM>. An axially right end portion of the valve housing <NUM> is inserted and fixed to the recessed portion 81b in a substantially sealed manner.

The center post <NUM> is made of a rigid body that is a magnetic material such as iron or silicon steel, and includes a cylindrical portion 82b in which an insertion hole 82c is formed into which the rod <NUM> extending in the axial direction is inserted; a flange portion 82d having an annular shape and extending from an outer peripheral surface of an axially left end portion of the cylindrical portion 82b in a radially outward direction; and a cylindrical guide portion 82e serving as a guide member having a small diameter and extending from an axially left end of the cylindrical portion 82b to the left in the axial direction. Incidentally, the insertion hole 82c formed in the cylindrical portion 82b penetrates through the cylindrical portion 82b to the inside of the cylindrical guide portion 82e in the axial direction. The cylindrical guide portion 82e is provided with a communication hole 82f penetrating through the cylindrical guide portion 82e in the radial direction, and communicating with the insertion hole 82c. In addition, a range of the rod <NUM> inserted into the cylindrical guide portion 82e has a constricted shape in which the range of the rod <NUM> has a smaller diameter than the abutting portion 53a, and thereby the cross-sectional area of a flow passage in the cylindrical guide portion 82e is increased.

In addition, the center post <NUM> is inserted and fixed to the axially right end portion of the valve housing <NUM>, which is inserted and fixed to the recessed portion 81b of the casing <NUM>, in a substantially sealed manner in a state where an axially right end surface of the flange portion 82d is abutted against a bottom surface of the recessed portion 81b of the casing <NUM> from the left in the axial direction.

As shown in <FIG>, the hollow cylindrical body <NUM> forming the CS valve body in the first embodiment includes a cylindrical portion 51b and a flange portion 51c having an annular shape and extending from an outer peripheral surface of an axially right end portion of the cylindrical portion 51b in the radially outward direction. The axially right end portion of the cylindrical portion 51b is externally fitted to the cylindrical guide portion 82e of the center post <NUM>. An inner peripheral surface of the cylindrical portion 51b is slidable on an outer peripheral surface of the cylindrical guide portion 82e in a substantially sealed state. In addition, an outer peripheral surface of the flange portion 51c is slidable on an inner peripheral surface of the valve housing <NUM> in a substantially sealed state. Incidentally, an opening portion 51d of an axially left end of the hollow cylindrical body <NUM> and the ring <NUM> are disposed in an external space S communicating with the control chamber of the variable displacement compressor. A control fluid supply chamber <NUM> to which the control fluid is supplied is provided inside the cylindrical portion 51b. Incidentally, the control fluid supply chamber <NUM> inside the cylindrical portion 51b and the space S in which the ring <NUM> is disposed correspond to one space in the present invention.

In addition, an inner peripheral surface of the cylindrical portion 51b of the hollow cylindrical body <NUM> and the outer peripheral surface of the cylindrical guide portion 82e of the center post <NUM> are slightly separated from each other in a radial direction, and thereby a very small gap is formed therebetween. The hollow cylindrical body <NUM> is smoothly movable relatively with respect to the cylindrical guide portion 82e of the center post <NUM> in the axial direction, and the gap functions as a clearance seal that divides the control fluid supply chamber <NUM> from a third suction fluid supply chamber <NUM> serving as the other space to be described later in a substantially sealed manner.

In addition, a coil spring <NUM> serving as biasing means is externally fitted to the hollow cylindrical body <NUM>. Incidentally, an axially left end of the coil spring <NUM> abuts against an axially right end surface of the ring <NUM> externally inserted and integrally fixed to an axially left end portion of the cylindrical portion 51b of the hollow cylindrical body <NUM>, and an axially right end of the coil spring <NUM> abuts against an axially left end surface of a partition wall 10b formed in a substantially axially central portion of the valve housing <NUM>, and thereby the hollow cylindrical body <NUM> and the ring <NUM> are biased to the left in the axial direction which is a valve opening direction of the CS valve <NUM>. In addition, the coil spring <NUM> is a compression spring. In such a manner, since the coil spring <NUM> is externally fitted to the hollow cylindrical body <NUM> to be guided by the hollow cylindrical body <NUM>, the movement and the deformation of the coil spring <NUM> in the radial direction are unlikely to occur.

The ring <NUM> forming the CS valve body in the first embodiment has a disk shape, and the outer diameter of the ring <NUM> is made larger than the inner diameter of the valve housing <NUM>. In addition, the tapered abutting portion 54a is formed in an outer diameter portion of the axially right end surface of the ring <NUM>, and a radially inner side of the abutting portion 54a faces a first suction fluid supply chamber <NUM> to be described later provided inside the valve housing <NUM>. In addition, an axially left end surface of the ring <NUM> faces the external space S (refer to <FIG>) communicating with the control chamber of the variable displacement compressor.

As shown in <FIG>, a Pc port <NUM> communicating with the control chamber of the variable displacement compressor, a Ps port <NUM> communicating with the suction chamber of the variable displacement compressor, and an orifice <NUM> communicating with the suction chamber of the variable displacement compressor are formed in the valve housing <NUM>. Incidentally, the orifice <NUM> is formed on an axially right side of the Ps port <NUM>, in detail, the inner peripheral surface of the valve housing <NUM> which is slidable on the outer peripheral surface of the flange portion 51c of the hollow cylindrical body <NUM>.

The valve housing <NUM> has a cylindrical shape, and the CS valve seat 10a is provided in an opening edge portion on the axially left side. In addition, inside the valve housing <NUM>, there are provided: the first suction fluid supply chamber <NUM> to which the suction fluid is supplied from the Ps port <NUM> on an outer periphery of the cylindrical portion 51b of the hollow cylindrical body <NUM> and which is partitioned off to an axially left side of the partition wall 10b; a second suction fluid supply chamber <NUM> to which the suction fluid is supplied from the first suction fluid supply chamber <NUM> and which is partitioned off to an axially right side of the partition wall 10b; the third suction fluid supply chamber <NUM> to which the suction fluid is supplied from the orifice <NUM> on an outer periphery of the cylindrical guide portion 82e of the center post <NUM> and which is partitioned off to an axially right side of the flange portion 51c of the hollow cylindrical body <NUM>; and a communication hole <NUM> axially penetrating through the center of the partition wall 10b extending in the radial between the first suction fluid supply chamber <NUM> and the second suction fluid supply chamber <NUM>. Incidentally, the first suction fluid supply chamber <NUM> is defined by the inner peripheral surface of the valve housing <NUM> on the axially left side of the partition wall 10b, an outer peripheral surface of the cylindrical portion 51b of the hollow cylindrical body <NUM>, an axially left surface of the partition wall 10b, and the axially right end surface of the ring <NUM>. In addition, the coil spring <NUM> which biases the hollow cylindrical body <NUM> forming the CS valve body and the ring <NUM> to the left in the axial direction is disposed in the first suction fluid supply chamber <NUM>.

The second suction fluid supply chamber <NUM> is defined by the inner peripheral surface of the valve housing <NUM> on the axially right side of the partition wall 10b, the outer peripheral surface of the cylindrical portion 51b of the hollow cylindrical body <NUM>, an axially right surface of the partition wall 10b, and an axially left surface of the flange portion 51c of the hollow cylindrical body <NUM>.

In addition, an inner peripheral surface of the communication hole <NUM> provided in the partition wall 10b of the valve housing <NUM> and the outer peripheral surface of the cylindrical portion 51b of the hollow cylindrical body <NUM> are separated from each other in the radial direction, and thereby a gap is formed therebetween. The gap functions as a communication passage that allows communication between the first suction fluid supply chamber <NUM> and the second suction fluid supply chamber <NUM>.

The third suction fluid supply chamber <NUM> is defined by the inner peripheral surface of the valve housing <NUM> on the axially right side of the partition wall 10b, the outer peripheral surface of the cylindrical guide portion 82e of the center post <NUM>, an axially left surface of the flange portion 82d of the center post <NUM>, and an axially right surface of the flange portion 51c of the hollow cylindrical body <NUM>. Incidentally, the third suction fluid supply chamber <NUM> communicates with the insertion hole 82c in the cylindrical portion 82b via the communication hole 82f provided in the cylindrical guide portion 82e of the center post <NUM>.

In addition, the inner peripheral surface of the valve housing <NUM> and the outer peripheral surface of the flange portion 51c of the hollow cylindrical body <NUM> are slightly separated from each other in the radial direction, and thereby a very small gap is formed therebetween. The hollow cylindrical body <NUM> is smoothly movable relatively with respect to the valve housing <NUM> in the axial direction, and the gap functions as a clearance seal that divides the second suction fluid supply chamber <NUM> from the third suction fluid supply chamber <NUM> in a substantially sealed manner.

Next, the operation of the capacity control valve V, namely, the opening and closing operation of the pilot valve <NUM> and the CS valve <NUM> will be described.

First, a non-energized state of the capacity control valve V will be described. As shown in <FIG> and <FIG>, when the capacity control valve V is in a non-energized state, the rod <NUM> is pressed to the right in the axial direction by biasing force of the coil spring <NUM> forming the solenoid <NUM>, so that the abutting portion 53a of the rod <NUM> is seated on the pilot valve seat 82a to close the pilot valve <NUM>. In addition, the hollow cylindrical body <NUM> and the ring <NUM> forming the CS valve body are pressed to the right in the axial direction against biasing force of the coil spring <NUM> by force induced by the control pressure Pc in the external space S (refer to <FIG>) applied to the axially left end surface of the ring <NUM>, the external space S communicating with the control chamber of the variable displacement compressor, so that the abutting portion 54a of the ring <NUM> is seated on the CS valve seat 10a to close the CS valve <NUM>.

At this time, the biasing force Fsp1 of the coil spring <NUM> toward the right in the axial direction and force FP15 induced by the control pressure Pc applied according to a pressure receiving seal diameter B (refer to <FIG>) in the pilot valve <NUM> to which the control fluid in the control fluid supply chamber <NUM> is applied are applied to the rod <NUM>. Force FP18 induced by the suction pressure Ps applied toward the left in the axial direction according to the pressure receiving seal diameter B in the pilot valve <NUM> to which the suction fluid in the third suction fluid supply chamber <NUM> is applied is applied to the rod <NUM>. Namely, force Frod1 = Fsp1 + FP15 - FP18 is applied to the rod <NUM>, given that a right direction is positive.

In addition, force induced by the control pressure Pc applied toward the right in the axial direction according to a pressure receiving seal diameter A (refer to <FIG>) in the CS valve <NUM> to which the control fluid is applied, in other words, force FP15+S induced by the control pressure Pc of the control fluid of the space S in which the control fluid supply chamber <NUM> and the ring <NUM> are disposed, and force FP17 induced by the suction pressure Ps applied according to a pressure receiving seal diameter C (refer to <FIG>) in the clearance seal between the inner peripheral surface of the valve housing <NUM> and the outer peripheral surface of the flange portion 51c of the hollow cylindrical body <NUM> to which the suction fluid in the second suction fluid supply chamber <NUM> is applied are applied to the hollow cylindrical body <NUM> and the ring <NUM> forming the CS valve body. The biasing force Fsp2 of the coil spring <NUM> toward the left in the axial direction, force FP16 induced by the suction pressure Ps applied according to the pressure receiving seal diameter A in the CS valve <NUM> to which the suction fluid in the first suction fluid supply chamber <NUM> is applied, and the force FP18 induced by pressure applied according to a pressure receiving seal diameter D (refer to <FIG>) in the clearance seal between the inner peripheral surface of the valve housing <NUM> and the outer peripheral surface of the flange portion 51c of the hollow cylindrical body <NUM> to which the fluid in the third suction fluid supply chamber <NUM> is applied are applied to the hollow cylindrical body <NUM> and the ring <NUM>. Namely, force Frod2 = FP15+S + FP17 - FP16 - FP18 - Fsp2 is applied to the hollow cylindrical body <NUM> and the ring <NUM> forming the CS valve body, given that the right direction is positive.

Incidentally, in the first embodiment, the pressure receiving seal diameter A to which the control fluid of the space S in which the control fluid supply chamber <NUM> and the ring <NUM> are disposed is applied, the pressure receiving seal diameter C to which the suction fluid in the second suction fluid supply chamber <NUM> is applied, and the pressure receiving seal diameter D to which the fluid in the third suction fluid supply chamber <NUM> is applied are the same (i.e., A = C = D).

In such a manner, since the fluid flowing into the first suction fluid supply chamber <NUM>, the second suction fluid supply chamber <NUM>, and the third suction fluid supply chamber <NUM> is the same as the suction fluid to be supplied from the Ps port <NUM> and the orifice <NUM>, and the pressure receiving seal diameters A, C, and D of the hollow cylindrical body <NUM> and the ring <NUM> forming the CS valve body are the same, the force FP16 induced by the suction pressure Ps applied to the axially right end surface of the ring <NUM> and the force FP17 induced by the suction pressure Ps applied to the axially left end surface of the flange portion 51c of the hollow cylindrical body <NUM> are the same (i.e., FP16 = FP17). Therefore, the force FP16 induced by the pressure of the fluid and the force FP17 induced by the pressure of the fluid are cancelled. Namely, practically, the force Frod2 = FP15+S - FP18 - Fsp2 is applied to the hollow cylindrical body <NUM> and the ring <NUM> forming the CS valve body, given that the right direction is positive.

Next, an energized state of the capacity control valve V will be described. Here, particularly, as shown in <FIG>, an operation in which the CS valve <NUM> is fully opened in a maximum energized state of the capacity control valve V will be described. When electromagnetic force Fsol generated by the application of electric current to the solenoid <NUM> exceeds the force Frod1 (i.e., Fsol > Frod1), the movable iron core <NUM> is pulled toward the axially left side, namely, toward a center post <NUM> side, and the rod <NUM> fixed to the movable iron core <NUM> moves to the left in the axial direction, and thereby the abutting portion 53a of the rod <NUM> separates from the pilot valve seat 82a of the center post <NUM> to fully open the pilot valve <NUM>. Accordingly, the fluid in the control fluid supply chamber <NUM> is introduced into the third suction fluid supply chamber <NUM> through the insertion hole 82c and the communication hole 82f which are formed in the cylindrical guide portion 82e of the center post <NUM>, and the pressure of the fluid in the third suction fluid supply chamber <NUM> rises.

When the pressure of the fluid in the third suction fluid supply chamber <NUM> is raised by the opening of the pilot valve <NUM>, and the differential pressure between the pressure of the fluid in the control fluid supply chamber <NUM> and the pressure of the fluid in the third suction fluid supply chamber <NUM> reaches a predetermined value or less, namely, the resultant force of the force FP18 induced by the pressure of the fluid applied to the hollow cylindrical body <NUM> and the ring <NUM> forming the CS valve body to the left in the axial direction and the biasing force Fsp2 of the coil spring <NUM> exceeds the force FP15+S induced by the control pressure Pc of the control fluid applied to the ring <NUM> forming the CS valve body to the right in the axial direction (i.e., FP15+S < FP18 + Fsp2), the abutting portion 54a of the ring <NUM> separates from the CS valve seat 10a of the valve housing <NUM>, and thereafter, the hollow cylindrical body <NUM> and the ring <NUM> move to the left in the axial direction, and the movable iron core <NUM> abuts against the center post <NUM> (refer to <FIG>), so that movement to the left in the axial direction is restricted and the CS valve <NUM> is fully opened.

In addition, even when the capacity control valve V is in an energized state, namely, at the time of normal control, in other words, at the time of so-called duty control, the pilot valve <NUM> is slightly opened with low electric current, the pressure in the third suction fluid supply chamber <NUM> is raised, and the differential pressure applied to the hollow cylindrical body <NUM> and the ring <NUM> forming the CS valve body is the predetermined value or less, and thereby the hollow cylindrical body <NUM> and the ring <NUM> can be stroked more than the stroke width of the rod <NUM> by driving force of the solenoid <NUM> to open CS valve <NUM>. In such a manner, the opening degree of the CS valve <NUM> is adjustable according to the opening degree of the pilot valve <NUM>.

In addition, since the capacity control valve V performs Pc-Ps control to open and close the CS valve <NUM> so that the control fluid of the control pressure Pc supplied from the Pc port <NUM> is supplied to the suction chamber via the Ps port <NUM> and the control pressure Pc of the control chamber is lowered, namely, since the discharge fluid of the discharge pressure Pd which is a high pressure is not directly controlled, the control pressure Pc can be finely adjusted by the valve opening degree of the CS valve <NUM> to be adjusted by balancing between the electromagnetic force of the solenoid <NUM> and the differential pressure applied to the hollow cylindrical body <NUM> and the ring <NUM> forming the CS valve body.

As described above, in the capacity control valve V, when the pilot valve <NUM> to be driven by the solenoid <NUM> is opened, the pressure in the third suction fluid supply chamber <NUM> is raised, and the differential pressure applied to the hollow cylindrical body <NUM> and the ring <NUM> forming the CS valve body reaches the predetermined value or less, the CS valve <NUM> is opened. Therefore, the driving electric power of the solenoid <NUM> can be reduced, and the valve opening degree of the CS valve <NUM> can be increased. In such a manner, since the opening degree of the CS valve <NUM> can be increased, even when the target value is large, a large flow rate can be promptly supplied, and the variable displacement compressor can be controlled with good response.

In addition, since the orifice <NUM> discharges the fluid in the third suction fluid supply chamber <NUM> toward the suction chamber of the variable displacement compressor in which an external suction fluid is housed, the fluid can be circulated in a closed system.

In addition, the opening degree of the pilot valve <NUM> is adjustable by adjusting electric current that energizes the solenoid <NUM>, and thereby the pressure of the fluid in the third suction fluid supply chamber <NUM> is adjustable, so that the opening degree of the CS valve <NUM> is adjustable.

In addition, since the CS valve body includes the hollow cylindrical body <NUM> with an outer flange, and the flange portion 51c of the hollow cylindrical body <NUM> slides on the inner peripheral surface of the valve housing <NUM>, the suction fluid supplied from the orifice <NUM> to the third suction fluid supply chamber <NUM> can be kept in a substantially sealed state by the clearance seal formed between the inner peripheral surface of the valve housing <NUM> and the outer peripheral surface of the flange portion 51c of the hollow cylindrical body <NUM>. In other words, since the suction fluid is easily maintained in the third suction fluid supply chamber <NUM>, in a non-energized state of the capacity control valve V, it is easy to maintain the differential pressure between the control fluid supply chamber <NUM> and the third suction fluid supply chamber <NUM> at a predetermined value or more, and maintain a valve closed state of the CS valve <NUM>. In addition, since the control fluid supply chamber <NUM>, the second suction fluid supply chamber <NUM>, and the third suction fluid supply chamber <NUM> are divided from each other in a substantially sealed manner by the clearance seal formed between the inner peripheral surface of the valve housing <NUM> and the outer peripheral surface of the flange portion 51c of the hollow cylindrical body <NUM> and the clearance seal formed between the inner peripheral surface of the cylindrical portion 51b of the hollow cylindrical body <NUM> and the outer peripheral surface of the cylindrical guide portion 82e of the center post <NUM>, there is no need to separately prepare a member that divides the control fluid supply chamber <NUM>, the second suction fluid supply chamber <NUM>, and the third suction fluid supply chamber <NUM> from each other, the number of components is reduced, and the structure of the capacity control valve V can be simplified.

In addition, since the outer peripheral surface of the flange portion 51c of the hollow cylindrical body <NUM> slides on the inner peripheral surface of the valve housing <NUM>, and the inner peripheral surface of the cylindrical portion 51b of the hollow cylindrical body <NUM> slides on the outer peripheral surface of the cylindrical guide portion 82e of the center post <NUM>, the hollow cylindrical body <NUM> is guided by the inner peripheral surface of the valve housing <NUM> and the outer peripheral surface of the cylindrical guide portion 82e of the center post <NUM>, and thereby the accuracy of operation of the hollow cylindrical body <NUM> and the ring <NUM> forming the CS valve body can be improved.

In addition, since the orifice <NUM> is provided in the valve housing <NUM>, the structure can be such that the orifice is not provided in the hollow cylindrical body <NUM> or the ring <NUM> forming the CS valve body, so that the hollow cylindrical body <NUM> and the ring <NUM> are unlikely to be tilted and are smoothly movable, and the capacity control valve V can be compactly configured.

In addition, since the coil spring <NUM> which biases the hollow cylindrical body <NUM> and the ring <NUM> to the left in the axial direction which is the valve opening direction of the CS valve <NUM> is disposed in the first suction fluid supply chamber <NUM> into which the suction fluid flows through the Ps port <NUM> on the outer periphery of the cylindrical portion 51b of the hollow cylindrical body <NUM> forming the CS valve body, a space in which the coil spring <NUM> is disposed is not required to be secured on a solenoid <NUM> side, and the capacity control valve V can be compactly configured. In addition, since the coil spring <NUM> is disposed on a side opposite to the solenoid <NUM> with the partition wall 10b of the valve housing <NUM> interposed therebetween, the operation of the hollow cylindrical body <NUM> and the ring <NUM> can be stabilized.

In addition, since the coil spring <NUM> is provided which biases the hollow cylindrical body <NUM> and the ring <NUM> to the left in the axial direction which is the valve opening direction of the CS valve <NUM>, when the control pressure Pc of the control fluid and the suction pressure Ps of the suction fluid are equal, the CS valve <NUM> can be opened. Therefore, when the variable displacement compressor is started after being stopped for a long period of time, the pressure of the control fluid can be promptly lowered.

In addition, since the pilot valve seat 82a is formed in the control fluid supply chamber <NUM>, and the control pressure Pc in the control fluid supply chamber <NUM> is applied to the axially left end portion of the rod <NUM> to the right in the axial direction which is the valve closing direction of the pilot valve <NUM>, the pilot valve <NUM> can be prevented from being opened when the solenoid <NUM> is not energized.

In addition, since the CS valve body is formed of the hollow cylindrical body <NUM> with an outer flange, and the ring <NUM> that is externally inserted and fixed to the hollow cylindrical body <NUM> of the CS valve body in an airtight manner and includes the abutting portion 54a which abuts against the CS valve seat 10a of the valve housing <NUM>, the CS valve <NUM> can be easily assembled and configured while securing a large flow rate of the fluid in the CS valve <NUM>.

Incidentally, in the first embodiment, a mode has been provided as an example in which the pressure receiving seal diameter A to which the control fluid of the space S in which the control fluid supply chamber <NUM> and the ring <NUM> are disposed is applied, the pressure receiving seal diameter C to which the suction fluid in the second suction fluid supply chamber <NUM> is applied, and the pressure receiving seal diameter D to which the fluid in the third suction fluid supply chamber <NUM> is applied are the same(i.e., A = C = D); however, the pressure receiving seal diameter A may be set slightly larger than the pressure receiving seal diameters C and D (i.e., A > C = D) to facilitate bringing the CS valve <NUM> into a closed state, or the pressure receiving seal diameter A may be set slightly smaller than the pressure receiving seal diameters C and D (i.e., A < C = D) to facilitate bringing the CS valve <NUM> into an open state. In such a manner, needless to say, the pressure receiving seal diameters A and B can be appropriately modified according to the application.

A capacity control valve according to a second embodiment of the present invention will be described with reference to <FIG>. Incidentally, description of the same and duplicated configurations as the configurations of the first embodiment will be omitted.

As shown in <FIG>, in the second embodiment of the present invention, an annular groove <NUM> which is recessed in a radially inward direction on an axially left side of the communication hole 82f is formed in an outer peripheral surface of a cylindrical guide portion 282e of a center post <NUM>, and an O-ring <NUM> made of rubber or resin and serving as an elastic seal member is disposed in the annular groove <NUM>. In addition, the O-ring <NUM> and the inner peripheral surface of the cylindrical portion 51b of the hollow cylindrical body <NUM> are slidable on each other. Incidentally, the elastic seal member is not limited to the O-ring made of rubber or resin, and may be, for example, a rectangular ring, a D-ring, an X-ring, a T-ring, a lip packing, etc. made of rubber or resin.

According to this configuration, since sealing performance between the control fluid supply chamber <NUM> to which the control fluid is supplied and the third suction fluid supply chamber <NUM> to which the suction fluid is supplied can be improved by disposing the O-ring <NUM>, which is provided in the annular groove <NUM> of the cylindrical guide portion 282e, between the inner peripheral surface of the cylindrical portion 51b of the hollow cylindrical body <NUM> and the outer peripheral surface of the cylindrical guide portion 282e of the center post <NUM>, in a non-energized state of the capacity control valve V, it is easy to maintain the differential pressure between the control fluid supply chamber <NUM> and the third suction fluid supply chamber <NUM> at a predetermined value or more, and maintain the CS valve <NUM> in a valve closed state. Incidentally, the elastic seal member may be provided on a hollow cylindrical body <NUM> side.

A capacity control valve according to a third embodiment of the present invention will be described with reference to <FIG>. Incidentally, description of the same and duplicated configurations as the configurations of the first embodiment will be omitted.

As shown in <FIG>, in the third embodiment of the present invention, in a hollow cylindrical body <NUM>, the inner diameter of the vicinity of an opening edge portion of an axially right end portion of a cylindrical portion 351b in which the flange portion 51c is formed is made large, and a tapered annular step portion 351e is formed on an axially left side of the opening edge portion.

In addition, an annular step portion <NUM> extending vertically in the radially inward direction is provided in a tip portion of a cylindrical guide portion 382e of a center post <NUM> in such a manner that an outer peripheral surface of the tip portion on the axially left side of the communication hole 82f is formed to have a small diameter, and in a non-energized state of the capacity control valve V, a corner of the annular step portion <NUM> and the annular step portion 351e of the hollow cylindrical body <NUM> can abut against each other.

According to this configuration, since a complementary step is formed of the tapered annular step portion 351e of the hollow cylindrical body <NUM> and the annular step portion <NUM> formed in the tip portion of the cylindrical guide portion 382e of the center post <NUM>, and a poppet structure is adopted in which the annular step portion <NUM> abuts against the tapered annular step portion 351e of the hollow cylindrical body <NUM> at a right angle, in a non-energized state of the capacity control valve V, sealing performance between the control fluid supply chamber <NUM> to which the control fluid is supplied and the third suction fluid supply chamber <NUM> to which the suction fluid is supplied can be improved. Therefore, it is easy to maintain the differential pressure between the control fluid supply chamber <NUM> and the third suction fluid supply chamber <NUM> at a predetermined value or more, and maintain the CS valve <NUM> in a valve closed state.

A capacity control valve according to a fourth embodiment of the present invention will be described with reference to <FIG>. Incidentally, description of the same and duplicated configurations as the configurations of the first embodiment will be omitted.

As shown in <FIG>, in the fourth embodiment, in a hollow cylindrical body <NUM>, the inner diameter of the vicinity of an opening edge portion of an axially right end portion of a cylindrical portion 451b in which the flange portion 51c is formed is made large, and an annular step portion 451e extending vertically is formed on an axially left side of the opening edge portion.

In addition, an annular step portion <NUM> extending vertically in the radially inward direction is provided in a tip portion of a cylindrical guide portion 482e of a center post <NUM> in such a manner that an outer peripheral surface of the tip portion on the axially left side of the communication hole 82f is formed to have a small diameter, and an O-ring <NUM> made of rubber or resin and serving as an elastic seal member is externally fitted to and disposed on an axially left side of the annular step portion <NUM>. Incidentally, in a non-energized state of the capacity control valve V, the O-ring <NUM> and the annular step portion 451e of the hollow cylindrical body <NUM> can abut against each other.

According to this configuration, since a complementary step is formed of the annular step portion 451e of the hollow cylindrical body <NUM> and the annular step portion <NUM> formed in the tip portion of the cylindrical guide portion 482e of the center post <NUM>, and the O-ring <NUM> is interposed between the annular step portion 451e of the hollow cylindrical body <NUM> and a side surface on the axially left side of the annular step portion <NUM> of the cylindrical guide portion 482e, in a non-energized state of the capacity control valve V, sealing performance between the control fluid supply chamber <NUM> to which the control fluid is supplied and the third suction fluid supply chamber <NUM> to which the suction fluid is supplied can be improved, and it is easy to maintain the differential pressure between the control fluid supply chamber <NUM> and the third suction fluid supply chamber <NUM> at a predetermined value or more, and maintain the CS valve <NUM> in a valve closed state.

A capacity control valve according to a fifth embodiment of the present invention will be described with reference to <FIG>. Incidentally, description of the same and duplicated configurations as the configurations of the first embodiment will be omitted.

As shown in <FIG>, in the fifth embodiment of the present invention, a ring <NUM> forming the CS valve body has a cylindrical shape, and the outer diameter of the ring <NUM> is made larger than the inner diameter of a valve housing <NUM>. In addition, a right-angled abutting portion 554a is formed in an outer diameter portion of an axially right end surface of the ring <NUM>.

In addition, an annular recessed portion 510c is provided in an axially left end portion of the valve housing <NUM> in which the Pc port <NUM> is formed by causing an opening edge portion of the axially left end portion to be recessed to the right in the axial direction, and an O-ring <NUM> made of rubber or resin and serving as an elastic body is disposed in the annular recessed portion 510c. In addition, the O-ring <NUM> forms a CS valve seat 556a from which the abutting portion 554a of the ring <NUM> forming the CS valve body comes into contact with and separates. Incidentally, the elastic body is not limited to the O-ring made of rubber or resin, and may be, for example, a rectangular ring or an X-ring made of rubber or resin, a C-ring made of metal, etc..

According to this configuration, in the CS valve <NUM>, since the O-ring <NUM> forms the CS valve seat 556a with which the abutting portion 554a of the ring <NUM> comes into contact with and separates, the CS valve <NUM> can be reliably closed.

Incidentally, since the fifth embodiment has a configuration in which the pressure receiving seal diameter A to which the control fluid of the space S (refer to <FIG>) in which the control fluid supply chamber <NUM> and the ring <NUM> are disposed is larger than the pressure receiving seal diameter C to which the suction fluid in the second suction fluid supply chamber <NUM> is applied and the pressure receiving seal diameter D to which the pressure of the fluid in the third suction fluid supply chamber <NUM> is applied (i.e., A > C = D), the CS valve <NUM> is easily maintained in a closed state in a non-energized state of the capacity control valve V.

The embodiments of the present invention have been described above with reference to the drawings; however, the specific configuration is not limited to the embodiments, and the present invention also includes changes or additions that are made without departing from the scope of the present invention.

For example, in the embodiments, a mode has been described in which the suction fluid is supplied to the third suction fluid supply chamber <NUM> through the orifice <NUM> formed in the valve housing; however, the present invention is not limited to this mode, and an orifice for supplying the suction fluid to the third suction fluid supply chamber <NUM> may be provided to penetrate through the flange portion of the hollow cylindrical body forming the CS valve body in the axial direction. In addition, in this case, the orifice formed in the flange portion of the hollow cylindrical body is not limited to a through-hole, and may have other shapes such as a cutout. In addition, the orifice may be a variable orifice in which the passage area of the fluid is variable.

In addition, in the embodiments, the coil spring <NUM> serving as biasing means has been described as being disposed in the first suction fluid supply chamber <NUM>; however, the present invention is not limited to this configuration, and for example, the coil spring <NUM> may be disposed in other places such as in the third suction fluid supply chamber <NUM> (refer to <FIG>) as long as the CS valve body can be biased in the valve opening direction of the CS valve <NUM>.

Claim 1:
A capacity control valve (V) comprising:
a valve housing (<NUM>) to which a suction fluid having a suction pressure and a control fluid having a control pressure are supplied;
a solenoid (<NUM>);
a CS valve (<NUM>) formed of a CS valve body (<NUM>, <NUM>, <NUM>, <NUM>) that partitions an inside of the valve housing (<NUM>) into a first space (<NUM>, S) and a second space (<NUM>) and moves according to the suction pressure (Ps) of the suction fluid and the control pressure (Pc) of the control fluid, and a CS valve seat (10a) with which the CS valve body (<NUM>, <NUM>, <NUM>, <NUM>) is configured to come into contact; and
a biasing member (<NUM>) that biases the CS valve body (<NUM>, <NUM>, <NUM>, <NUM>) in a valve opening direction of the CS valve (<NUM>); characterized by
a pilot valve (<NUM>) formed of a pilot valve body (<NUM>) to be driven by the solenoid (<NUM>) and a pilot valve seat (82a) with which the pilot valve body (<NUM>) is configured to come into contact,
wherein the control fluid flows into the first space (<NUM>), the suction fluid is flowable into the second space (<NUM>) via an orifice (<NUM>), and the control fluid is introduced into the second space (<NUM>) by the pilot valve (<NUM>).