JPH0249432B2 - DENDOBENNOBENJIKUKAITENTOMEICHINOCHOSEIHOHO - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention converts the rotation of a valve shaft, which is integrated with the rotor of a pulse motor, into a linear motion by screw action, and moves the valve seat and needle valve. This motor-operated valve has a built-in structure that controls the flow rate by changing the gap between the valves and mechanically stops the rotation of the pulse motor at a preset axial position of the valve shaft. Pin 15 to stop the rotation of the motor.
The present invention relates to a method for adjusting the valve shaft rotation stop position of an electric valve, which reduces the level of the shocking sound generated when the stopper 16 and stopper 17 come into contact with each other.

[Prior art] Conventional electric valves have a built-in structure that mechanically stops the rotation of the pulse motor.
An example of this will be explained with reference to FIG. 1. A valve shaft 1 is placed from the valve seat 2 side to a needle valve 3, a male screw 4, and a pulse motor rotor consisting of a cylindrical permanent magnet magnetized with multiple circumferences and multiple poles. The external threads 4 are formed by integrating them in the order of 5.
It is fitted with a propulsion bearing 9 fixed to the valve body 6 and having a female thread 8 cut in the center, and the bearing end 6 is fitted with a bearing 11 fixed in a case 10 made of a non-magnetic material.

The case 10 includes a rotor 5 of a pulse motor.
Stator coil 1 of the pulse motor is placed in the position corresponding to
2 is fixed.

Further, the case 10 is airtightly integrated with the valve body 7 having the fluid inlets and outlets 13 and 14 and the valve seat 2 by plasma welding or the like. Furthermore, a stop pin 1 is placed on the valve stem 1 a little apart from both ends of the male thread 4.
5 and 16 are fixed by a method such as press fitting,
A round pin-shaped stopper 17 for restricting the rotation of the stop pins 15 and 16 is fixed to the propulsion bearing 9 by penetrating it.

With the structure described above, when a predetermined amount of current is applied to the stator coil 12 of the pulse motor, the rotor 5 rotates, and the valve shaft 1 is rotated forward (closed) by the screw action of the male thread 4 and female thread 8. (in the valve-closing direction), the needle valve 3 seats on the valve seat 2 and closes, and the threaded portion 4 , 8 is set so that there is a very small gap between the valve part 3 and the valve seat 2 to avoid a situation where a strong screwing friction force is generated and the next valve opening movement becomes impossible. The stopper pin 15 or 16 comes into contact with the stopper 17, and the linear movement of the valve shaft is stopped.

In addition, the pin-shaped stopper 17 is selectively inserted into one of several fixing holes 19 formed at equal angles on the surface of the propulsion bearing 9 as shown in FIG. It is adjusted to reduce variations in the axial stop position within the shaft.

In the above-mentioned pulse motor, the rotation of the rotor repeatedly starts and stops for each pulse, and the rotational torque of the rotor 5 during this period starts from 0 and reaches half the step angle, that is, at the center. The rotational torque reaches its maximum at the point where the motor moves to the position, and returns to zero again at the end of the operation for all step angles.

Further, during this one operation, the rotational speed is also maximized (the maximum output point of the pulse motor) at the point where the rotational torque is maximum.

Therefore, if the stator coil 13 is arranged so that the stop pin 15 or 16 and the stopper 17 touch each other exactly at the center of the step angle,
The contact sound between the stop pin 15 or 16 and the stopper 17 (hereinafter referred to as stopper sound) becomes maximum,
On the other hand, if the stator coil 13 is arranged so that the stopper pin 15 or 16 contacts the stopper 17 at the start or end point of the step angle, the stopper noise will be minimized.

[Problems to be Solved by the Invention] When applying this type of electric valve to household appliances such as room air conditioners and gas combustion appliances, it is necessary to Regardless of the stop position, the initial value of the valve stem 1 is set to fully closed or fully open by applying a predetermined pulse necessary for the valve stem to go from fully open to fully closed. .

Further, when the rotor 5 is stopped by the contact between the stopper pins 15 and 16 and the stopper 17, the rotor is reversed by an amount equivalent to 0.1 to 0.2 pulses due to the reaction force at the time of contact. However, this is unavoidable due to the nature of the pulse motor.

Therefore, if the previous stop position of the valve stem was between fully closed and fully open, even after the stop pin 15 or 16 contacts the stopper 17, the drive pulse that rotates the rotor 5 is still applied to the stator. coil 12
Since it is applied continuously, a stop sound is generated continuously.

This stopper sound occurs when the rotation of the rotor 5 gains momentum, that is, when the position of the rotor's magnetic pole corresponding to the stator's magnetic pole is near the center of the step angle, when the stopper pin 15 or 16 When the stopper 17 comes into contact with the stopper 17, there is a problem in that a large impact sound and noise are generated as described above.

The present invention provides that the stopper sound is caused by the circumferential relative position of the rotor 5 and stator coil 12 of the pulse motor.
In other words, we focused on the experimental fact that the magnitude differs depending on the position at which the rotor 5 stops within one pulse, and after selecting the position of the stator coil where the stop noise is minimized, The present invention aims to provide a method of adjusting the rotation stop position of an electric valve that generates little noise by fixing the motor-operated valve on the case 10.

[Means for Solving the Problems] The method of adjusting the rotation stop position of an electric valve according to the present invention is as follows: By energizing the stator coil 12 of a pulse motor fitted into the outer periphery of a case 10 made of a non-magnetic material, A rotor 5 of a pulse motor integrally formed with a valve shaft 1 having a male thread 4 housed in a case is rotated, and this rotation is converted into linear motion of the valve shaft 1 by a propulsion bearing 9 having a female thread 8 cut. The degree of opening of the valve seat 2 is controlled by
6, and a stopper 17 for restricting the rotation of the stop pins 15, 16 is fixed to the propulsion bearing 9 by penetrating it. By energizing the child coil 12, the stop pin 15 or 16 and the stopper 17 are brought into contact once, and then the stator coil 12 is manually rotated in the circumferential direction while continuously applying driving pulses to the stator coil 12. The stator coil 12 is fixed on the case 10 after selecting a position where the contact noise between the stop pin 15 or 16 and the stopper 17 is minimized.

[Operation] The method for adjusting the rotation stop position of an electric valve of the present invention is as follows:
When determining the abutting positions of the retaining pins 15 and 16 and the stopper 17, the position of the magnetic poles of the rotor coil 5 with respect to the magnetic poles of the stator coil 12 is determined so that the rotational torque of the rotor in the operating section of one pulse is 0. The stopper noise can be kept as low as possible by adjusting the position closer to the start point of the step angle or the end point of all step angles.

[Example] The electrically operated valve of the present invention has completely the same component structure as the conventional electrically operated valve explained in FIGS. 1 and 2, so detailed explanation thereof will be omitted.

In the present invention, when fitting the stator coil 12 to the case 10, the stator coil 12 is provisionally fixed in a rotatable state with a slight gap in advance, and the initial position of the valve stem 1 is fully closed or closed. Set the stop pin 15 or 16 to either fully open, and apply a predetermined pulse necessary for the valve stem to go from fully open to fully closed so that the stop pin 15 or 16 and stopper 17 come into contact with each other. let it come into contact,
After that, repeat so that they are in contact with each other,
In this state, rotate and adjust the stator coil 12 on the case 10 to the position where the stop noise is minimized, and then use adhesive or the like to attach the stator coil 12 to the case 1.
It is fixed above 0.

Note that the rotation/adjustment range described above is sufficient to be within the step angle θ of the pulse motor of ±1/2 with the stator coil 12 temporarily fixed position as the center.

[Effects of the Invention] As a result of adjusting the valve shaft rotation stop position by the method of the present invention, the stopper sound is reduced to the A-weighted noise level compared to the conventional one.
We were able to achieve a reduction of 15dB(A) from 50dB(A) to 35dB(A).

In this way, the stopper noise can be easily reduced in the final step of the manufacturing process of an electric valve by utilizing the operating characteristics of the pulse motor, and is an industrially useful invention.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional side view showing an example of the configuration of an electric valve to which the present invention is applied. FIG. 2 is a perspective view of the propulsion bearing of the electric valve shown in FIG. 1. 1...Valve stem, 2...Valve seat, 3...Needle valve, 4...Male thread, 5...Rotor of pulse motor, 6...Bearing end, 7
...Valve body, 8...Female thread, 9...Propulsion bearing, 10...Case, 11...Bearing, 12...Stator coil of pulse motor, 13, 14...Fluid inlet/outlet, 15, 16
...stopping pin, 17...stopper, 19...fixing hole.

Claims (1)

[Claims] 1. By energizing the stator coil 12 of the pulse motor fitted into the outer periphery of the case 10 made of a non-magnetic material, the valve shaft 1 having the male thread 4 housed in the case is integrated with the stator coil 12 of the pulse motor. Rotor 5 of the formed pulse motor
The degree of opening of the valve seat 2 is controlled by converting this rotation into a linear movement of the valve shaft 1 by a propulsion bearing 9 with a female thread 8 cut. Set pin 15 a little apart from both ends,
16, and a stopper 17 for restricting the rotation of the stop pins 15, 16 is fixed to the propulsion bearing 9 by penetrating it. By energizing the child coil 12, the stop pin 15 or 16 and the stopper 17 are brought into contact once, and then the stator coil 12 is manually rotated in the circumferential direction while continuously applying driving pulses to the stator coil 12. The method for adjusting the rotation stop position of an electric valve is characterized in that the stator coil 12 is fixed on the case 10 after selecting the position where the contact noise between the stop pin 15 or 16 and the stopper 17 is minimized.