JP3037831B2 - Motor valve origin detection structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an electronically controlled expansion valve used in a refrigerating cycle of a room air conditioner or a car air conditioner, or a motor operated valve used as a proportional control valve used in combination with a microcomputer in general industrial fields. Origin detection structure.

[0002]

2. Description of the Related Art Conventionally, various types of motor-operated valves which are controlled by a microcomputer by combining a stepping motor and a valve have been invented. 6 and 7 show a longitudinal sectional view and a partial perspective view showing a stop mechanism of a conventional motor-operated valve, and the configuration will be described below. A conventional motor-operated valve rotates a motor rotor 4 integrally formed with a valve shaft 3 by energizing a stator coil 2 of a motor fixed to an outer peripheral portion of a case 1 made of a non-magnetic material. Is converted into linear motion of the valve shaft 3 by the propulsion bearing 5 to control the opening degree of the valve seat 6. The rotor 4 of the motor
The rotor sleeve 4a integrated with the rotor sleeve 4a has, on its inner peripheral surface, a convex portion 4b projecting radially only at one location.

[0004] On the other hand, a stop member 10 in which an upper protruding piece 10a and a lower protruding piece 10b are protruded in the radial direction with a vertical difference is previously loosely fitted to the mandrel 8 having a flange portion 8a at the lower end. At the center of the inner surface of the lid 7, the upper end of the mandrel 8 is fixed, and a stopper piece 9 is fixed at a position distant from the center. In addition,
The lower projecting piece 10b of the stop member 10 is adapted to abut on the rear surface or the front side of the convex portion 4b of the rotor sleeve according to the rotation direction of the rotor 4, and the upper projecting piece 1
Reference numeral 0a abuts on the front surface or the rear surface of the stopper piece 9 according to the rotation direction.

Next, the operation of this conventional product will be described. FIGS. 6 and 7 show an open state of the motor-operated valve. In this state, when the stator coil 2 is energized to rotate in the valve closing direction, the rotor of the motor is completely independent of the stop member 10. 4 rotates rightward when viewed from above, and the protrusion 4b of the rotor sleeve 4a is
hit b. Subsequently, when the rotor sleeve 4a rotates, the protruding piece 10b below the stopper member 10 is pushed by the protrusion 4b of the rotor sleeve 4a and rotates rightward, and eventually,
The protruding piece 10a above the stopper member 10 is
, And the rotor 4 stops at about one and a half rotation.

[0006]

As described above, the conventional motor-operated valve is provided with a stopper mechanism for driving with an excessive number of pulses. However, since the position of the valve cannot be detected, the home position is determined. As a method, when the power is turned on, regardless of the opening of the valve, the drive is controlled by the number of pulses sufficient to fully close or fully open regardless of the opening, and the position where the valve is mechanically stopped by the stopper mechanism is determined. After that, various drive controls of the valve were performed.

Therefore, depending on the position of the valve, the stopper piece 9 or the convex portion 4b of the motor rotor 4 and the protruding piece 10b of the stop member 10 collide many times for each drive pulse, thereby generating a noticeable noise or vibration. Alternatively, the life of the motor-operated valve was shortened. In addition, if the stepping motor loses synchronism due to a voltage drop or malfunctions, it is not possible to detect the deviation of the opening, and operation in this state may cause serious malfunction of the entire system. There was something. SUMMARY OF THE INVENTION The present invention provides a motor-operated valve capable of detecting a fully closed or fully open position of a valve with a simple structure and outputting an origin signal, thereby solving the conventional problems.

[0008]

According to a first aspect of the present invention, which relates to a structure for detecting the origin of a motor-operated valve, as shown in FIG. 1, it is integrated with a rotor 4 of a motor in a case 1 made of a non-magnetic material. A protrusion 4b is formed by protruding one place in the radial direction on the inner peripheral surface of the rotor sleeve 4a thus formed, while the center of the inner surface of the lid 7 has an upper end of a mandrel 8 having a flange 8a at the lower end. The stopper piece 9 is suspended and fixed at a position distant from the central portion while the mandrel 8 is provided with a vertical difference so that the upper protruding piece 10a and the lower protruding piece 10b protrude in the radial direction. The stopper member 10 is loosely fitted, and the upper protruding piece 10a is
The stopper piece 9 is arranged so as to abut on the front or rear surface in the rotation direction, and the protrusion 4b of the rotor sleeve 4a is positioned in contact with the rear or front surface in the rotation direction of the lower protruding piece 10b. In the motor-operated valve, magnetic detection means 11 for detecting magnetism is provided at an appropriate position on the outer peripheral surface of the case 1 or the lid 7, and the mandrel 8 is provided with a movable member 13 having a magnet 12 fixed to a distal end portion so as to rotate freely. Mounting, the movable member 13 or the magnet 12,
The protruding piece 10a above the stop member 10 is arranged so as to be able to abut, and the spring means 14 is arranged so that the magnet 12 is always kept away from the operating range of the magnetic detecting means 11 and abuts on the magnet abutting piece 17. It is.

[0009] In the second invention, as shown in FIG.
The spring means is a spiral spring 18, and the magnet 12 is attached to the tip of the spiral spring 18 or, as shown in FIG. 4, the magnet 12 is directly attached to the tip of the upper protruding piece 10a of the stopper member 10. Thus, the structure of the motor-operated valve is simplified.

[0010] In the third invention, as shown in FIG.
A stopper 15 is mounted on the lid 7 or the case so as to cover the upper surface of the center of the lid 7, which is a fixing portion of the mandrel 8, and the magnet detection means 11 is held at one end of the stopper 15 to stop from the magnet 12. Each member such as the movable member 13 and the mandrel 8 reaching the metal fitting 15 is made of a magnetic material, and the magnetic flux emitted from the pole of the magnet 12 passes through each magnetic material to reach the magnetic detecting means 11, and then the magnetic detecting means. The magnet 12 passes through the lid 7 located at the lower part of
By forming a magnetic flux loop reaching the other pole, the magnetism of the magnet 12 can be used effectively.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. Note that the basic structure is the same as that of the conventional product except for the component for detecting the origin, and thus the description is omitted. The origin detecting structure of the present invention includes a mandrel 8, a stopper member 10, a movable member 13, a magnet 12, a spring means 14, a stopper piece 9 provided on a substrate 16 and It is composed of a contact piece 17 and magnetic detection means 11 arranged on the upper surface of the lid 7 or on the side surface of the case 1.

The mandrel 8 has the same shape as that of a conventional product.
a and a movable member 13 having a magnet 12 fixed to the distal end thereof are rotatably fitted around the mandrel 8 as a rotation axis. The substrate 16 has a stopper piece 9 and a magnet contact piece 17 provided on the back surface thereof in a hanging manner.
Is fixed to the center of the back surface of the lid 7. Spring means 14
Has one end wrapped around the mandrel 8 and fixed to the movable member 13 with the other end extended. The magnet 12 at the tip of the movable member 13 is urged to always lightly press the magnet contact piece 17. ing.

On the other hand, as the magnetic detecting means 11, for example, a magnetic reaction type reed switch is used, and the magnetic detecting means 11 comprises a stopper piece 9 provided on the substrate 16.
And is attached to the upper surface of the lid 7 corresponding to. In the present embodiment, the magnet 12 on the movable member 13 is urged by the spring means 14 so as to always lightly press the magnet contact piece 17, so that the magnet 12 is always held away from the magnetic detection means 11. However, for example, by narrowing the movable range of the spring means 14 against which the movable member 13 is pressed, the magnet 12 can be always held at a position other than the magnetic detection range of the magnetic detection means 11. With the structure, the magnet holding piece 17 is not particularly required.

[0014]

Other Embodiments FIGS. 3 to 5 show another embodiment, and FIG. 3 shows a case in which the magnet 12 is directly attached to a spiral spring 18. FIG. 4 shows a state in which a magnet 12 is attached to an upper protruding piece 10 a of a stopper member 10.
These are examples in which the substrate 16 disposed inside the lid 7 is omitted to simplify the internal structure. FIG.
The magnetic detection means 11 (reed switch) is fixed to the upper surface of the lid 7 via a stopper 15, and the stopper 15 is attached to the mandrel 8. The mandrel 8, the movable member 13, and the stopper 15 are made of a magnetic material while being fixed to the upper surface of the lid 7 so as to cover the upper end fixing portion.

[Action]

Next, the operation of the present invention will be described. FIGS. 1 and 2 show an open state of the electric valve. In this state, the magnet 12 fixed to the movable member 13 is pressed to the magnet contact piece 17 to the left by the spring means 14. Here, when the stator coil 4 is energized so as to rotate in the valve closing direction (right direction), the rotor 4 of the motor makes one rotation to the right when viewed from above, regardless of the stop member 10. The protruding portion 4b of the rotor sleeve 4a hits the projecting piece 10b below the stopper member 10.

Subsequently, when the rotor sleeve 4a rotates,
The lower protruding piece 10b is pushed by the projection 4b of the rotor sleeve 4a, and the stopper member 10 rotates together with the rotor sleeve 4a. When further rotated, the upwardly projecting piece 10a abuts on the movable member 13, and the movable member 13 rotates rightward while digging into the spring 14, and the magnet 12 is eventually moved by the movable member 1.
2, the rotor 4 is fully closed and stopped in about one and a half rotations in the example of FIG. At this time, the magnetic detection means (reed switch) 11 provided above the stopper piece 9
Reacts with the magnetism of the magnet 12 to close the internal contact and output a signal indicating that the valve is fully closed. The rotation angle of the rotor 4 can be set to a desired angle depending on the position of the magnet contact piece 17. For example, in FIG. 2, when the magnet contact piece 17 is provided on the left side of the stopper piece 9 or when the magnet contact piece 17 is also used as the stopper piece 9, two rotations can be set.

When the valve rotates backward (opens) to the left from this position, the movable member 13 is pushed back by the spring means 14 to weaken the magnetism and release the contact of the magnetism detection means (reed switch). The biasing direction of the movable member 13 by the spring means 14 is reversed, and the mounting position of the reed switch 11 is
It is clear that a full open signal can be output in the same manner as described above by changing to the left side of the stopper piece 9 in the above, and the description is omitted.

FIG. 3 shows an example in which the functions of the movable member 13 and the spring means 14 are replaced by a spiral spring 18, and the end of the spiral spring 18 is pressed by the upper protruding piece 10a and the magnet 12 is magnetically driven. It is moved to the position of the detecting means 11. FIG. 4 shows a state in which the magnet 12 is directly attached to the tip of the upwardly projecting piece 10a of the stopper member 10, and the stopper member 10 is directly opposed to the spring means 14 as shown in FIGS. To move.

Next, the operation of FIG. 5 will be described. Magnetic flux emitted from one pole (for example, N pole) of the magnet 12 passes through the movable member 13, the mandrel 8, the lid 7, and the stopper 15, which are made of a magnetic material, and reaches the reed switch 11, which is magnetic detection means. Next, the magnetic flux forms a magnetic flux loop that reaches the other pole (S-pole) of the magnet 12 through the lid 7 located below the reed switch 11, thereby concentrating the magnetism of the magnet 12 on the reed switch 11. I can guide you. Furthermore, since the stopper 15 covers only half of the reed switch 11 and opens the other half, the reed switch 1
Both ends of 1 efficiently become S and N poles, and the sensitivity is increased, so that even a weak magnetic flux can sufficiently react. In addition,
In this embodiment, an example is described in which a reed switch is used as the magnetism detecting means, but any means may be used as long as it is a sensor that responds to magnetism. Further, since the magnetism generated from the coil 2 does not normally leak to the outside (other than the rotor of the motor), it does not affect the operation of the present invention.

[0020]

According to the present invention, one or both of the fully-closed state and the fully-opened state can be detected as required, so that when fully closed (fully open), the motor drive is stopped on the control program. It becomes possible. Therefore, it is not necessary to drive the motor unnecessarily even after fully closing (fully opening) as in the related art, and it is possible to prevent collision noise and vibration caused by a mechanical stop mechanism. In addition, by inputting the origin signal every time the valve is fully closed (fully open), the control side confirms that the valve is operating according to the control command. Can be greatly improved in reliability. Further, the present invention provides a method of effectively guiding the magnetic flux generated from the magnet 12 to the magnetic detection means. According to this method, even an inexpensive magnet having a weak magnetic force can be employed, and the electric valve itself can be used. Can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a valve-opened state of a motor-operated valve according to the present invention.

FIG. 2 is a partial perspective view showing an origin detection structure of FIG. 1;

FIG. 3 is a partial perspective view showing another embodiment of the movable member of the motor-operated valve according to the present invention.

FIG. 4 is a partial perspective view showing another embodiment of the movable member of the motor-operated valve according to the present invention.

FIG. 5 is a partial perspective view showing one embodiment of the magnetic detection means of the motor-operated valve according to the present invention.

FIG. 6 is a vertical sectional view showing a valve-opened state of a conventional electric valve.

FIG. 7 is a partial perspective view showing the stopper mechanism of FIG. 1;

[Description of Signs ] 1 case, 2 stator coils, 3 valve shaft, 4
Rotor, 4a rotor sleeve, 4b protrusion, 5
Propulsion bearing, 6 Valve seat, 7 Lid, 8 Mandrel, 9
Stopper piece, 10 stopper member, 10a upper projecting piece, 10b lower projecting piece, 11 magnetic detecting means,
12 magnet, 13 movable member, 14 spring means, 15 stopper, 16 substrate, 17 magnet contact piece, 18 spiral spring.

Claims (3)

(57) [Claims] 1. A convex portion 4b is formed on an inner peripheral surface of a rotor sleeve 4a integrated with a rotor 4 of a motor in a case 1 made of a non-magnetic material by protruding one place in a radial direction. At the center of the inner surface of the lid 7, a flange 8 is provided at the lower end.
a, the upper end of the mandrel 8 is fixed, and a stopper piece 9 is suspended and fixed at a position away from the center. The mandrel 8 is provided with a vertical difference so that an upper protruding piece 10a and a lower protruding piece are provided. A stopper member 10 having a radially projecting 10b is loosely fitted, and the stopper piece 9 is arranged to contact the front or rear surface in the rotational direction of the upper projecting piece 10a. In a motor-operated valve having a structure in which a convex portion 4b of a rotor sleeve 4a is abutted on a rear surface or a front surface, a magnetism detecting means 11 for detecting magnetism at an appropriate position on the outer peripheral surface of the case 1 or the lid 7 is provided. A movable member 13 having a magnet 12 fixed to a tip portion is rotatably attached to the mandrel 8, and the movable member 13 or the magnet 1
2 and the protruding piece 10a above the stopper member 10 are arranged so as to be able to contact with each other, and the magnet 12 is normally
3. The structure for detecting the origin of a motor-operated valve, wherein the spring means 14 is arranged so as to be kept away from the operating range of the electric valve. 2. An origin detection structure for a motor-operated valve according to claim 1, wherein the magnet is directly attached to the spring means or the upper projecting piece of the stopper member. 3. A magnetic detecting means 11 at one end and a lid 7 at the other end.
Attachment 15 which covers the attachment and fixing portion of the mandrel 8 and the mandrel 8 is mounted on the lid 7, and the stopper 12 is further attached from the magnet 12.
5, the movable member 13 and the mandrel 8 are made of a magnetic material, and the magnetic flux from the pole of the magnet 12 passes through each magnetic material to reach the magnetic detecting means 11, and then the magnetic detecting means 1
1 through the upper surface of the lid 7
3. The structure for detecting the origin of a motor-operated valve according to claim 1, wherein a magnetic flux loop reaching another pole is formed.