JP4028265B2 - Electric control valve - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electric control valve, and more particularly, to a rotary valve body type (one rotation type) reversible electric control valve for reversibly controlling a refrigerant flow rate in a vapor compression cooling / heating circuit.
[0002]
[Prior art]
As a one-rotation type electric control valve (rotary control valve) used in the refrigeration cycle apparatus, a cylindrical valve body having an eccentric outer peripheral surface is circular as shown in JP-A-8-31823. The valve chamber has a cross-sectional shape of the valve chamber, and is rotatably arranged around its own central axis. The inlet port and the outlet port open to the peripheral surface of the valve chamber, and the cylindrical valve body has its own central axis. By rotating around, the radial gap dimension between the eccentric outer peripheral surface of the cylindrical valve body and the inner peripheral surface of the valve chamber, in other words, the degree of communication between the inlet port and the outlet port changes. An electric control valve that quantitatively controls the flow rate between the inlet port and the outlet port according to this is known.
[0003]
[Problems to be solved by the invention]
Since the conventional electric control valve described above has an inlet port and an outlet port on the rotary sliding peripheral surface of the cylindrical valve body, the fully closed state cannot be basically obtained, and its application is limited depending on the system purpose. In addition, because of the structure of the flow metering unit, it is not suitable for flow control of a large flow rate, and the fluid pressure difference and the fluid flow act in the rotational direction of the cylindrical valve body, and the predetermined rotational position of the cylindrical valve body is determined. In order to remain stationary, the stator coil must be energized at all times. For this reason, power consumption is large and it is contrary to energy saving.
[0004]
The present invention has been made to solve the above-described problems, and can bidirectionally control the flow rate control in a reversible and quantitative manner, and can obtain a fully closed state. In addition, the required torque for driving the valve body is small, no holding power is required to hold the valve body in a predetermined rotational position, and energy saving is achieved. Also, the stator of the valve drive motor An object of the present invention is to provide a compact and inexpensive electric control valve that can easily replace a coil assembly.
[0005]
[Means for Solving the Problems]
In order to achieve the above-described object, an electric control valve according to the present invention includes a lower lid member penetrating and forming a first inlet / outlet port and a second inlet / outlet port, and a cap-like airtightly connected to the lower lid member. The rotor case, a rotor with a multi-pole magnet rotatably provided in the rotor case, a stator coil assembly mounted on the outside of the rotor case and constituting a stepping motor together with the rotor, and the rotor case The end plate is fixed to the lower lid member, and both ends are closed by end plates, and one end plate is formed with a first valve port that communicates directly with the first input / output port, and the other end plate A cylindrical case penetrating through a second valve port communicating with the second inlet / outlet port through an inner space of the rotor case and defining a valve chamber therein, and a rotation within the cylindrical case. Capable, and having a rotary valve element which is movable in the rotation axis direction, the rotary valve body, the rotation axis direction relative to the rotor through the central through hole of the other end plate engaged by slidably rotational direction, said rotary valve element to the previous SL pressure in the first input and the port by the differential pressure between the second input and the port pressure to move the rotation axis direction, of the pressure difference Depending on the direction, the end face of the rotary valve body is pressed against one of the one end plate and the other end plate facing the end face, and the first end plate on the side where the end face is pressed open and closed according to the valve port or the second valve port to the rotational displacement amount of the rotary valve member which is rotatably driven by the rotor, the rotor is rotatable in a free state free bearings into the cylindrical portion of the rotor case The stator of the stator coil assembly It said rotor by detent torque or force of yl to static constant rotation in rotor case the central position.
[0006]
According to the electric control valve configured as described above, in the state where the pressure of the first inlet / outlet port is higher than the pressure of the second inlet / outlet port, the end face of the rotary valve body is caused by the differential pressure to the other side of the cylindrical case. When the rotary valve body is pressed against the end plate and is rotated by the rotor in this state, the end face of the rotary valve body slides against the other end plate of the cylindrical case, and the rotational displacement of the rotary valve body is reduced. In response, the second valve port is opened and closed. On the other hand, when the pressure at the second inlet / outlet port is higher than the pressure at the first inlet / outlet port, the differential pressure causes the end face of the rotary valve body to be pressed against one end plate of the cylindrical case. When the valve body is rotationally driven by the rotor, the end face of the rotary valve body slides with respect to one end plate of the cylindrical case, and opens and closes the first valve port according to the rotational displacement amount of the rotary valve body. . Further, the rotary valve body is engaged with the rotor in the rotational direction so as to be slidable in the rotational axis direction through the center through hole of the other end plate, and is rotated by the rotor. Depending on the pressure difference between the pressure at the inlet / outlet port and the pressure at the second inlet / outlet port and its direction, the rotary valve body slides and moves independently in the rotational axis direction relative to the rotor which can rotate in a free state without bearings .
[0007]
In the electric control valve according to the present invention, the flow metering shape part formed by a stepped surface is formed on the end face of the rotary valve body, and the flow metering shape part changing according to the rotational displacement amount of the rotary valve body and the first The flow rate is controlled quantitatively according to the degree of overlap with the second valve port or the second valve port.
[0008]
In the electric control valve according to the present invention, the lower lid member and the rotor are provided with a collision contact type stopper that sets the maximum rotational position of the rotor in the forward and reverse directions, and the stator coil assembly is mounted on the rotor case. A positioning engagement portion is provided on the outer lid member and the stator coil assembly so as to determine a circumferential mounting position of the stator coil assembly with respect to the lower lid member.
[0009]
According to the electric control valve of the present invention, the forward and reverse maximum rotational positions of the rotor with respect to the collision lowering stopper lower lid member, that is, the fully opened position and the valve closed position of the rotary valve body are determined, and the lower lid is determined by the positioning engagement portion. The mounting position of the stator coil assembly in the circumferential direction with respect to the member is determined, and this determines the motor excitation phase for obtaining the fully open position and the valve closed position of the rotary valve body.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
1 to 4 show an embodiment of an electric control valve according to the present invention.
[0012]
As shown in FIG. 1, the electric control valve includes a stainless steel disc-shaped lower lid member 11, and a cap-shaped rotor case 12 whose periphery is hermetically connected to the lower lid member 11 by welding or the like. The rotor chamber 13 having a sealed structure is defined inside.
[0013]
The lower lid member 11 is formed with a first inlet / outlet port 16 and a second inlet / outlet port 17 connected to the joint pipes 14 and 15, respectively.
[0014]
The rotor case 12 has a cylindrical portion 12A and a canopy portion 12B, and is entirely made of a nonmagnetic material. A rotor 18 is rotatably provided in the rotor chamber 13. The rotor 18 is a rotor with a multi-pole magnet whose outer peripheral surface is magnetized (not shown), and a stator coil assembly 19 fitted and mounted on the outer periphery of the cylindrical portion 12A of the rotor case 12 to form a stepping motor. 20 is constituted.
[0015]
The stator coil assembly 19 is detachably attached to the outer periphery of the cylindrical portion 12A of the rotor case 12, and includes an upper outer casing 21 having a plurality of upper magnetic pole teeth 21A in a comb shape in the circumferential direction, and an upper outer casing. A lower outer rod 22 attached to the lower side of the flange 21 and having a plurality of lower magnetic pole teeth 22A in a comb shape in the circumferential direction, and upper and lower disposed in the upper outer flange 21 and the lower outer flange 22 It has two-stage stator coils 23 and 24, a coil energizing connector portion 25 and the like, and the whole is resin-sealed with sealing resins 26 and 26a.
[0016]
Since the stator coil assembly 19 is detachably attached to the outer periphery of the cylindrical portion 12A of the rotor case 12, the stator coil assembly 19 of the stepping motor 20 that is a valve driving motor can be easily replaced. To get.
[0017]
A spring piece-like positioning piece 27 is attached to the lower outer flange 22, and a plurality of coil portion positioning recesses 11A are formed at equal intervals in the circumferential direction on the outer peripheral edge of the lower lid member 11. The positioning piece 27 engages with one of the coil portion positioning recesses 11 </ b> A, thereby positioning the stator coil assembly 19 in the circumferential direction with respect to the lower lid member 11.
[0018]
As shown in FIG. 3, a circular concave portion 11B is formed on the upper surface of the lower lid member 11 at a position including the first input / output port 16, and the circular concave portion 11B is made of stainless steel made of a cup-shaped press product. A cylindrical case 28 having an airtight structure is fixed by fitting brazing so that the case main body 28B and an upper end plate 28A hermetically welded to the case main body 28B so as to close the upper opening of the case main body 28B.
[0019]
The cylindrical case 28 has an upper end closed by an upper end plate 28A and a lower end closed by a bottom plate (end plate) 28C of the case main body 28B to define a valve chamber 29 therein as shown in FIG. ing. The bottom plate (end plate) 28C of the cylindrical case 28 is formed with a first valve port 30 that directly communicates with the first input / output port 16, and the inner space (rotor chamber 13) of the rotor case 12 is formed in the upper end plate 28A. A second valve port 31 communicating with the second inlet / outlet port 17 is formed through.
[0020]
In the cylindrical case 28, that is, in the valve chamber 29, a substantially columnar rotary valve body 32 is provided so as to be rotatable and movable in the rotation axis direction (vertical direction). The rotary valve body 32 is formed of a resin molded product, and a fully-open opening 32A extending between both upper and lower ends, and flow metering shape portions 32B and 32C having stepped surfaces are integrally formed on both upper and lower end surfaces. . As shown in FIG. 3, the flow rate measuring shape portions 32 </ b> B and 32 </ b> C each have a slanted convex shape.
[0021]
Rotary valve member 32 is pressed against the pressure and the second input and the bottom plate 28C, or the upper end plate 28A of the flow metering shaped portion 32B or 32C of the valve body end faces by the differential pressure between the pressure ports 17 of the first input and port 16 4, the flow metering shape portion 32B or 32C on the pressing end surface side and the first valve port 30 or the second valve according to the rotational displacement amount around the rotation center axis of the rotary valve body 32 itself, as shown in FIG. The flow rate control is quantitatively performed by changing the degree of superposition with the valve port 31.
[0022]
As shown in FIG. 1, a stainless steel center pin 33 is insert-molded in the rotary valve body 32. The center pin 33 protrudes into the rotor chamber 13 above the cylindrical case 28 through a center through hole 28D formed through the center of the upper end plate 28A. A connecting fitting 34 having a plurality of engaging claws 34A is fixed to the protruding end of the center pin 33 by caulking or welding. The coupling metal 34 is engaged with an engagement recess 18A formed in the lower bottom portion of the rotor 18 by an engagement claw 34A so as to be slidable in the vertical direction. In short, the rotary valve body 32 is engaged with the rotor 18 in the rotational direction so as to be slidable in the rotational axis direction via the center through hole 28D of the other end plate 28A.
[0023]
A fully closed / open stopper pin 11C is formed on the upper surface side of the lower lid member 11, and a stopper piece 18B is integrally formed on the lower end side of the rotor 18. When the stopper piece 18B collides with the fully closed / open stopper pin 11C by the forward / reverse rotation of the rotor 18, the forward / reverse maximum rotational position of the rotor 18, that is, the fully open position and the valve closed position of the rotary valve body 32 are determined. . By this positioning and positioning of the stator coil assembly 19 in the circumferential direction with respect to the lower lid member 11 by engagement of the positioning piece 27 and the coil portion positioning recess 11A, the fully open position and the valve closed position of the rotary valve body 32 are set. The excitation phase of the stepping motor 20 to be obtained is determined.
[0024]
As shown in FIG. 2, the upper end 18D of the center rod portion 18C of the rotor 18 is only loosely fitted in the recess 12C formed in the canopy portion 12B of the rotor case 12 with a gap t. 18 is rotatably provided in the cylindrical portion 12A of the rotor case 12 in a non-bearing free state, and rotates statically at the center position of the rotor case by the detent torque or magnetic force of the stator coils 23 and 24 of the stator coil assembly 19. It has a structure.
[0025]
Next, the operation of the electric control valve configured as described above will be described.
In a state where the pressure of the first inlet / outlet port 16 is higher than the pressure of the second inlet / outlet port 17, the rotary valve body 32 is caused by the differential pressure acting in the direction of the rotation center axis of the rotary valve body 32 from the lower end side to the upper end side. 32C is pressed against the upper end plate 28A of the cylindrical case 28, and the rotary valve body 32 is rotationally driven by the rotor 18 in this state, whereby the flow rate measurement on the upper end side of the rotary valve body 32 is performed. The shape portion 32 </ b> C slides with respect to the upper end plate 28 </ b> A of the cylindrical case 28, and the second valve port 31 is opened / closed according to the rotational displacement amount of the rotary valve body 32.
[0026]
The opening and closing of the second valve port 31 will be described in detail. When the number of input pulses of the stepping motor 20 is 0, the stopper piece 18B of the rotor 18 comes into contact with one surface of the fully closed / open stopper pin 11C, and as shown in FIG. The entire measurement shape portion 32C is superimposed on the second valve port 31, and a fully closed state is obtained by sliding the end faces (planes) together.
[0027]
Due to the rotation of the rotor 18 in accordance with the increase in the number of input pulses of the stepping motor 20, the rotary valve body 32 rotates in the clockwise direction as viewed in FIG. 4, and the flow rate measuring shape portion according to the rotation angle (rotational displacement amount). The overlapping region of the second valve port 31 of 32C decreases, the opening degree (effective opening area) of the second valve port 31 increases as the rotation angle of the rotary valve body 32 increases, and the second valve port 31 Measurement according to the effective opening area 31 is performed, and quantitative flow rate control is performed. Each state when the number of input pulses of the stepping motor 20 is 20 pulses, 40 pulses, and 60 pulses is shown in FIGS. 4B, 4C, and 4D.
[0028]
When the number of input pulses of the stepping motor 20 is, for example, 80 pulses, the further rotation of the rotary valve body 32 in the clockwise direction as seen in FIG. 4 causes the opening for full opening as shown in FIG. The portion 32A is completely aligned with the second valve port 31 and is fully opened. At this time, the stopper piece 18B of the rotor 18 contacts the other surface of the fully closed / open stopper pin 11C, and further rotation of the rotary valve body 32 in the clockwise direction is prohibited.
[0029]
Thereby, the valve opening characteristic as shown by the valve opening characteristic -A in FIG. 5 is obtained. This valve opening characteristic can be set to any value by setting the shape of the flow metering shape portion 32C.
[0030]
In a state where the pressure of the second inlet / outlet port 17 is higher than the pressure of the first inlet / outlet port 16, the rotary valve body 32 is driven by the differential pressure acting in the direction of the rotation center axis of the rotary valve body 32 from the upper end side to the lower end side. The flow rate measurement shape portion 32B on the lower end side of the rotary valve body 32 is pressed against the bottom plate 28C of the cylindrical case 28, and the rotary valve body 32 is rotationally driven by the rotor 18 in this state. The portion 32B slides relative to the bottom plate 28C of the cylindrical case 28, and the first valve port 30 is opened and closed according to the rotational displacement amount of the rotary valve body 32.
[0031]
Also in this case, when the number of input pulses of the stepping motor 20 is 0, the stopper piece 18B of the rotor 18 comes into contact with one surface of the fully closed / full open stopper pin 11C, as shown in FIG. In this way, the entire flow metering shape portion 32B is superimposed on the first valve port 30, and the fully closed state is obtained by sliding the end faces (planes) together.
[0032]
Due to the rotation of the rotor 18 in accordance with the increase in the number of input pulses of the stepping motor 20, the rotary valve body 32 rotates in the clockwise direction as viewed in FIG. 4, and the flow rate measuring shape portion according to the rotation angle (rotational displacement amount). The overlap region of the first valve port 30 of 32B decreases, the opening degree (effective opening area) of the first valve port 30 increases as the rotation angle of the rotary valve body 32 increases, and the first valve port Measurement according to the effective opening area of 30 is performed, and quantitative flow rate control is performed. Each state when the number of input pulses of the stepping motor 20 is 20 pulses, 40 pulses, and 60 pulses is shown in FIGS. 4B, 4C, and 4D.
[0033]
When the number of input pulses of the stepping motor 20 is, for example, 80 pulses, the further rotation of the rotary valve body 32 in the clockwise direction as seen in FIG. 4 causes the opening for full opening as shown in FIG. The portion 32A is completely aligned with the first valve port 30 and is fully opened. At this time, the stopper piece 18B of the rotor 18 contacts the other surface of the fully closed / open stopper pin 11C, and further rotation of the rotary valve body 32 in the clockwise direction is prohibited.
[0034]
Thereby, the valve opening characteristic as shown by the valve opening characteristic -B in FIG. 5 is obtained. This valve opening characteristic can be arbitrarily set separately from the valve opening characteristic -A by setting the shape of the flow metering shape portion 32B. Thereby, in the vapor compression type cooling / heating circuit, it is possible to appropriately perform refrigerant flow rate control for obtaining system purposes such as the degree of superheat of the refrigerant, the discharge temperature, and the heat exchange load amount.
[0035]
With the valve structure and valve opening / closing operation described above, bidirectional flow control can be controlled reversibly and quantitatively, and a fully closed state can be obtained. Can also respond.
[0036]
In the electric control valve configured as described above, the valve opening / closing operation load is only a sliding resistance of the rotary valve body 32 due to the differential pressure load acting on the rotary valve body 32, and a spring or the like serving as the valve opening / closing operation load. Is not used at all, the required torque for driving the rotary valve body 32 is small, the power consumption of the stepping motor 20 is small, and holding power for holding the rotary valve body 32 in a predetermined rotational position may be required. As a result, excellent energy saving can be achieved.
[0037]
In addition, the rotor 18 is provided so as to be rotatable in a free state without bearings, and is rotated at a center position of the rotor case by the detent torque or magnetic force of the stator coils 23 and 24 of the stator coil assembly 19. However, this is performed in a low frictional resistance state, which also reduces the power consumption of the stepping motor 20.
[0038]
【The invention's effect】
As can be understood from the above description, according to the electric control valve of the present invention, either one of the end faces of the rotary valve body depends on the pressure difference between the pressure of the first inlet / outlet port and the pressure of the second inlet / outlet port and the direction thereof . There is pressed against the end plate of the cylindrical case to face the end surface, Ri by that the rotary valve member in this state is rotated by the rotor, the rotating valve body side end surface is pressed against the cylindrical case Since the first inlet / outlet port or the second valve port is opened / closed according to the amount of rotational displacement of the rotary valve body, the first inlet / outlet port pressure and the second inlet / outlet port pressure are slid with respect to the end plate . The flow control in both directions can be reversibly and quantitatively controlled according to the differential pressure, and the fully closed state can be obtained. The compact design according to the diameter of the valve port or the like can also cope with the flow control of a large flow rate. Moreover, the rotary valve member by the pressure difference and its direction between the first input and the port pressure and the pressure in the second and out port is moved to slide alone the rotation axis direction with respect to the rotor, which rotor The force that moves in the direction of the rotation axis does not act, and the valve opening / closing operating load is a spring that becomes the valve opening / closing operating load only by the sliding resistance of the rotating valve body due to the differential pressure load acting on the rotating valve body Since the required torque for driving the rotary valve body is small, the power consumption of the stepping motor is small, and the holding power for holding the rotary valve body in a predetermined rotational position is not required. Excellent energy saving can be achieved.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an embodiment of an electric control valve according to the present invention.
FIG. 2 is an enlarged view showing a rotor upper structure of one embodiment of the electric control valve according to the present invention.
3A is an exploded perspective view of a valve structure portion of one embodiment of an electric control valve according to the present invention, and FIG. 3B is an assembled perspective view of the same.
FIGS. 4 (a) to 4 (e) are plan views of a main part showing a valve opening / closing state of one embodiment of an electric control valve according to the present invention.
FIG. 5 is a graph showing an example of valve opening characteristics of the electric control valve according to the present invention.
[Explanation of symbols]
11 Lower lid member 11A Coil portion positioning recess 11C Fully closed / full open stopper pin 18 Rotor 18B Stopper piece 19 Stator coil assembly 20 Stepping motor 27 Positioning piece 28 Cylindrical case 30 First valve port 31 Second valve port 32 Rotary valve body 32B, 32C Flow metering shape

Claims (3)

A lower lid member formed so as to penetrate the first inlet / outlet port and the second inlet / outlet port;
A cap-like rotor case hermetically connected to the lower lid member;
A rotor with a multipole magnet rotatably provided in the rotor case;
A stator coil assembly mounted on the outside of the rotor case and constituting a stepping motor together with the rotor ;
In the rotor case, fixed to the lower lid member, both ends are closed by end plates, and one end plate is formed through a first valve port that communicates directly with the first input / output port, A cylindrical case penetrating through the second valve port communicating with the second inlet / outlet port through the inner space of the rotor case in the end plate, and defining a valve chamber therein;
A rotating valve body provided in the cylindrical case so as to be rotatable and movable in the rotation axis direction ;
The rotary valve body is engaged in the rotational direction so as to be slidable in the rotational axis direction with respect to the rotor via a central through hole of the other end plate,
The rotary valve member by the pressure difference between the previous SL pressure in the first input and port the second input and the port pressure to move the rotation axis direction, the end face is the end face of the rotary valve member by way of the differential pressure either pressed against the one of said one end plate opposite to the other end plate, said first valve port or the second valve port of the end plate of the end face is pressed against the side the the and opening and closing in accordance with the amount of rotational displacement of the rotation driven the rotary valve member by the rotor,
The rotor rotatably provided in the free state free bearings into the cylindrical portion of the rotor casing, the rotor conductive dynamic control of static constant rotation in rotor case the central position by the detent torque or force of the stator coil assembly of the stator coil valve.   A flow metering shape portion is formed on the end face of the rotary valve body by a stepped surface, and the flow metering shape portion and the first valve port or the second valve port change according to the rotational displacement amount of the rotary valve body. The electric control valve according to claim 1, wherein the flow rate control is quantitatively performed according to a degree of superimposition with the control signal.   The lower lid member and the rotor are each provided with a collision contact type stopper that sets the maximum rotational position of the rotor in the forward and reverse directions, and the stator coil assembly is detachably mounted on the outer side of the rotor case. The electric control valve according to claim 1 or 2, wherein a positioning engagement portion for determining a circumferential mounting position of the stator coil assembly with respect to the lower lid member is provided on the lid member and the stator coil assembly.

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