JP2562131Y2 - Actuator for valve - Google Patents

Description

[Detailed description of the invention]

[0001]

[Industrial applications] The present invention is mainly used for cold and hot water, oil,
The present invention relates to a valve actuator having a gear mechanism to be mounted on a valve of piping of gas or the like, and more particularly, to a valve actuator which minimizes noise generated by gears when the actuator is operated or when an operation direction is switched.

[0002]

2. Description of the Related Art Most of gears used in conventional actuator gear mechanisms are metal spur gears.
There is a backlash between the meshing of the large gear and the small gear or the rack and the pinion, and the number of simultaneous meshing teeth is slightly more than one. There is a problem that the sound is further reverberated in the interior and the sound becomes further louder, giving a feeling of discomfort and deteriorating the living environment and working environment.

[0003] This phenomenon is particularly severe when the actuator is operated, when the operation direction is switched, or when the rotation speed of the electric motor is high. One-way operation is performed using electricity, air pressure, hydraulic pressure, or the like as a power source. In the spring return type actuator that performs the operation in the other direction by the elastic force of the compressed spring during the operation in one direction, it is separated from the power source and switched to the operation in the opposite direction by the elastic force of the spring. Occasionally, the large spring force of the spring was applied at once in the opposite direction, and the backlash between the teeth was shifted to the opposite side of the teeth, so that there was a great tendency to generate particularly loud noise.

[0004]

SUMMARY OF THE INVENTION The actuator according to the present invention is characterized in that the above-mentioned conventional actuator having a gear mechanism generates noise when the operation or the switching of the operation direction is performed, which causes discomfort. To prevent the living environment and working environment from deteriorating.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is to reduce the number of multi-stage gears from the drive shaft of an electric motor.
Speed gear mechanism rotates in one direction around the output shaft of the valve
And the spring compressed during this one-way rotation
Open and close the valve by rotating it in the opposite direction with elastic force
Actuator for driven spring return type valve
A first gear of a motor shaft of the gear mechanism.
And the second stage gear as a helical gear, and combine this helical gear
It was formed of an elastic material such as resin .

In this case, it is preferable that one or both of the pair of helical gears or both of the gears or the portion including the teeth is formed of an elastic material such as hard rubber or soft synthetic resin. Further, the above configuration is a cylinder type actuator that uses fluid pressure such as air pressure or hydraulic pressure as a power source, and a mechanism that converts linear motion into rotary motion is a gear mechanism, and a spring return type electric motor actuator or This is effective when the air motor actuator is a gear mechanism and the reduction mechanism is a gear mechanism.Especially, one-way operation is performed by using electric, pneumatic, or hydraulic power as a power source, and the other-direction operation is performed in the one-way operation. This is more effective in the case of a spring return type in which the spring is sometimes compressed by the elastic force of the spring.

[0007]

Since the actuator of the present invention is constructed as described above, first, at least one or a pair of gears of the gear mechanism or a part of the gear including the teeth is made of an elastic material such as hard rubber or soft synthetic resin. When formed of a material having
When the actuator is operated, in particular, when the operation direction is switched, the engagement between the one gear and the metal gear and the elastic material of the pair of gears absorb the shock and do not generate an impact sound. For this reason, one or both gears of all gear pairs in which an impact is likely to occur and an impact sound is likely to be generated, the entire gear or the part of the gear including the teeth is formed of an elastic material such as hard rubber or soft synthetic resin. If so, this actuator emits very little noise. When the teeth are formed of a material having elasticity as described above, the teeth also function to supplement the processing accuracy of the gear.

Next, when the teeth of at least one pair of gears of the gear mechanism are helical gears, even if those teeth are made of metal, the backlash is extremely small and the number of simultaneous meshing teeth is two or more. Because it becomes large, the impact is extremely small,
Makes almost no impact sound. For this reason, if the spur gears are made of helical gears for all the gear pairs that are likely to generate an impact and easily generate an impact sound, the actuator generates less noise.

Furthermore, if one or both of the gears of the helical gear pair or all of the gears including the teeth are formed of an elastic material such as hard rubber or soft synthetic resin, noise is generated. The effect of preventing gear loss is further increased, and the machining accuracy of the gear is supplemented.

When a mechanism for converting a linear motion of a cylinder type actuator using fluid pressure such as air pressure, hydraulic pressure or the like as a power source into a rotary motion is a gear mechanism such as a rack and pinion type by meshing a rack and a pinion, Since the backlash between the rack and the pinion generates an impact sound during operation, and particularly when the operation is switched, the elastic material is used for the gear teeth as described above, or the helical gear is used. If so, there is a remarkable effect of preventing generation of noise.

When the reduction mechanism of the spring return type electric motor actuator or the air motor actuator is a gear mechanism such as a multi-stage gear type, the entire backlash is an accumulation of the backlash of the individual gear pairs and is extremely large. Since the impact is large and the number of gear pairs is large, there are many opportunities for the impact to occur. Therefore, if a material having elasticity is used for the gear teeth or a helical gear is used as described above, there is a remarkable effect of preventing generation of noise. In this case, if the small gear mounted on the motor shaft rotating at the highest speed and the large gear meshing with the small gear are formed of an elastic material, or a helical gear is used, a great noise reduction effect can be obtained.

The above-mentioned cylinder type actuator, electric motor actuator, and air motor actuator perform one-way operation using electric power, pneumatic pressure, hydraulic pressure, or the like as a power source, and perform the other-direction operation by a spring spring compressed during one-way operation. If the spring return type is performed by the spring force, the spring will be separated from the power source and switched to the operation in the opposite direction by the spring force of the spring, and the large spring force of the spring will move in the opposite direction. In addition, because the backlash between the teeth shifts to the opposite side of the teeth and the teeth strongly strike each other and tend to generate particularly loud noises, as described above, the elastic material is used for the gears. When used for teeth or helical gears, the effect of preventing the generation of noise is particularly remarkable.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the actuator of the present invention will be described below with reference to the drawings. FIG. 1 is a cross sectional view of a spring return type cylinder type actuator,
In this actuator, a mechanism that converts a linear motion of a piston into a rotational motion of an output shaft is a rack and pinion type gear mechanism by meshing between a rack and a pinion.

In FIG. 1, 1 is an actuator, 2 is a cylinder, 3 and 4 are pistons, 5 and 6 are racks formed integrally with the pistons 3 and 4, respectively, 7 is a pinion, and a pinion 7 is connected to an output shaft 8. Fixed. Reference numerals 9 and 10 denote springs, which are mounted between the piston 3 and the spring case 11 in a compressed state. In addition, 12 and 13 are O-rings of the pistons 3 and 4, 14 is a bolt device for preventing spring protrusion when disassembled, and 15 is a stopper cup for preventing spring protrusion. The pinion 7 is made of a soft synthetic resin such as PTFE according to the present invention, and meshes with the racks 5 and 6 with almost no backlash by utilizing the elasticity of the soft synthetic resin.

In FIG. 1, when compressed air is fed from an intake / exhaust port 16 provided in a cylinder 2, the pressure causes the piston 3 to move leftward and the piston 4 to move rightward. Racks 5 and 6 integrally formed with
Rotates the pinion 7 counterclockwise. At this time, the air in the cylinder 2 to the left of the piston 3 and the air in the spring case 11 together with the air in the cylinder 2 to the right of the piston 4 connected by the flow path 17 After passing through the gap 18, the spring case 11
Is discharged from the breathing port 19. Also, the springs 9 and 10
Is further compressed by the leftward movement of the piston 3.

Next, when the intake / exhaust port 16 is switched to the open-to-atmosphere state, the piston 3 moves rightward due to the elastic force of the springs 9 and 10, and the pinion 7 is rotated clockwise by the rack 5 integrated with the piston 3. Rotated. Note that the piston 4 moves to the left as the rack 6 moves to the left due to the clockwise rotation of the pinion 7, so that both move to the left.

In this actuator 1, the pinion 7 is
Since it is formed of an elastic material such as TFE, the teeth of the pinion 7 and the rack 5 or 6 when operating in one direction.
No impact sound is generated even if the teeth hit each other. Also, when the operation direction is switched, a large elastic force of the spring is applied to the piston 3 in a direction opposite to the previous direction, and the backlash between the rack 5 and the pinion 7 is shifted to the opposite side of the tooth. However, the elastic material absorbs the impact and does not generate an impact sound. Further, in the actuator 1, since the racks 5 and 6 and the pinion 7 are meshed with almost no backlash by utilizing the elasticity of the material of the pinion 7 as described above, no impact is generated and noise is generated. Absent. Further, since the pinion 7 is made of a material having elasticity, the pinion 7 and the racks 5 and 6 serve to compensate for the processing accuracy and eccentricity.

When the portions including the teeth of the racks 5 and 6 are also formed of an elastic material such as hard rubber or soft synthetic resin, the noise reduction effect is further increased. Also, racks 5 and 6
If the pinion 7 is made of metal or a helical gear, there is an effect. If one or both of them are made of an elastic material such as hard rubber or soft synthetic resin, the noise reduction effect is further increased.

FIG. 2 is a longitudinal sectional view of an electric motor actuator having a multi-stage gear type reduction mechanism, wherein 21 is an actuator, 22 is an output shaft, 23 is an electric motor,
4, 25 and 26 are small gears, 27, 28 and 29 are large gears, and the small gear 24 is a rotating shaft 30 of the electric motor 23.
The small gear 25 is the large gear 27, and the small gear 26 is the large gear 2.
8 and a large gear 29 are fixed to the output shaft 22, respectively. A large gear 27 to which the small gear 25 is fixed is connected to the output shaft 2.
The large gear 28 to which the small gear 26 is fixed is an intermediate shaft 31.
It is rotatably mounted on.

The small gears 24, 25 and 26
The small gear 24 and the large gear 27, the small gear 25 and the large gear 28, and the small gear 26 and the large gear 29 are almost made of a soft synthetic resin such as TFE by utilizing the elasticity of the soft synthetic resin. Engage without backlash. In FIG. 2, 32 and 33 are limit switches,
34 and 35 are cams for operating the limit switch,
36 is an opening support needle.

In FIG. 2, when the electric motor 23 rotates, the small gear 24 fixed to the rotating shaft 30
From the small gear 25 fixed to the large gear 27 to the large gear 28
From the small gear 26 fixed to the large gear 28 to the large gear 29
The rotation is transmitted while being decelerated, and the output shaft 22 fixed to the large gear 29 rotates. The output shaft 22 normally rotates the valve shaft of the valve to open and close the valve. In this case, the valve is opened and closed by changing the direction of rotation, and
Some are performed by rotation in the same direction.

In this actuator 21, the rotating shaft 30
Backlash between the motor and the output shaft 22 (play in the rotating direction)
Is the accumulation of the backlash of each meshing of the three-stage gear pair, which is extremely large, and the impact force becomes large.
This is remarkable when the opening rotation and the closing rotation have different rotation directions. In addition, since there are three places where the gears mesh with each other, there are many opportunities for impact to occur.

However, in the actuator 21, since the small gears 24, 25 and 26 are formed of a material having elasticity such as PTFE as described above, the material absorbs impact and does not generate noise. In addition, since the meshing of the three gears is made use of the elasticity of this material so as not to cause backlash, no impact is generated and no noise is generated. In this case, only the small gear 24 and the large gear 27 may be formed of a synthetic resin. Further, an elastic material acts to compensate for processing accuracy and eccentricity.

FIGS. 3 to 5 show another embodiment of the present invention, which is an electric motor actuator 41 of a spring return type. In the figure, the first stage gear 42 and the second stage gear 43 of the motor shaft 41a are formed of an elastic material such as synthetic resin, and the first stage gear 42 and the second stage gear 43 are formed into a helical gear. I do. 4 and 5, R
Reference numeral 1 denotes the rotation of the motor, the rotation direction of the gear R2, and R3 the rotation force of the spring in the opposite direction. Also in this embodiment, similarly to the above embodiment, it is possible to minimize the noise generated from the meshing state of the gears.

[0025]

[Effects of the Invention] As described above, the actuator of the present invention emits very little noise at the time of operation and switching of the operation direction, and does not cause discomfort and deteriorate the living environment and work environment. When the rotation speed of the motor is high, an extremely effective effect is exhibited. Further, the processing accuracy and the eccentricity of the gear can be compensated. FIG. 6 is a noise curve of an electric motor actuator having a multi-stage gear type reduction mechanism used in the experiment, wherein the gear is a metal spur gear. FIG.
Is a noise curve when a small gear fixed to the motor shaft of the same actuator and a large gear meshing with the small gear are changed to an elastic material, and both FIGS. 6 and 7 are schematically drawn. Furthermore, the spring force of the spring separated from the power source
The first stage gear with a large number of rotations with reverse rotation added at once
And the second stage gear strongly strike, but this gear has elasticity
The use of helical gears made of helical gears minimizes noise generation
It is possible to Also, from the fully opened state in FIG.
Compared to the noise from the spring return until closing,
Spring spring from fully open to fully closed in Fig. 7 of the invention
Turn noise was significantly reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a spring-return type cylinder actuator according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view of an electric motor actuator having a multi-stage gear type reduction mechanism according to another embodiment of the present invention.

FIG. 3 is an explanatory plan view of a spring return type electric motor actuator showing another embodiment of the present invention.

FIG. 4 is a partially enlarged view showing a meshing state in a rotation direction of the motor in FIG. 3;

FIG. 5 is a partially enlarged view showing a meshing state in a rotation direction by a spring return in FIG. 3;

FIG. 6 is a schematic diagram of a noise curve of a conventional actuator used in an experiment.

FIG. 7 is a schematic diagram of a noise curve when a part of gears of the same actuator as in FIG. 3 is changed to a material having elasticity.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Actuator 2 Cylinder 3, 4 Piston 5, 6 Rack 7 Pinion 8 Output shaft 9, 10 Spring 16 Intake / exhaust port 21 Actuator 22 Output shaft 23 Electric motor 24, 25, 26 Small gear 27, 28, 29 Large gear 41 Actuator 42 First stage gear 43 Second stage gear

Claims (1)

(57) [Scope of request for utility model registration] 1. A multi-stage gear type reduction from a drive shaft of an electric motor.
Speed gear mechanism rotates in one direction around the output shaft of the valve
And the spring compressed during this one-way rotation
Open and close the valve by rotating it in the opposite direction with elastic force
Actuator for driven spring return type valve
A first gear of a motor shaft of the gear mechanism.
And the second stage gear as a helical gear, and combine this helical gear
An actuator for a valve , comprising an elastic material such as a resin .