JP2005133872A - Actuator for valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact and economical actuator for a valve capable of achieving a large reduction gear ratio with the small number of gears while applying an electric motor and the like as a power source, being commonly used in a rotating valve through an inner gearing planetary gear reduction gear mechanism, accurately controlling an angle of a valve, accurately detecting an opening and closing position of the valve, reducing its size and weight, further reducing the cost, and commonly using a valve opening detecting member and other components regardless of the magnitude of output torque. <P>SOLUTION: This actuator for the valve applies the reduction gear mechanism 7 capable of outputting a rotating component of an external gear 10 by controlling the oscillating rotation of the external gear 10 receiving the eccentric rotation from an eccentric body 9 eccentrically rotated in interlocking with a rotation driving source 3, a supporting plate 27 is fixed to a base body 2 for bearing a control shaft 23 extended from the output shaft 8, an oscillation control part 24 is mounted on a control shaft 23 bearing position of the supporting plate 27, and a mounting plate 22 loading the valve opening detecting member 21 is positioned and fixed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a valve actuator for mounting on a rotary valve such as a ball valve or a butterfly valve, and particularly to an rotary motor such as a ball valve or a butterfly valve via a speed reduction mechanism using an electric motor or the like as a power source. The present invention relates to a valve actuator that can be shared.

  A conventional valve actuator is a reduction gear in which a spur gear train is engaged and connected in multiple stages between the output shaft and the motor rotation shaft in order to reduce the rotational force from the motor and transmit it to the output shaft. By using this speed reduction mechanism, the rotational force from the motor is decelerated and transmitted to the output shaft, and then transmitted to the valve shaft connected to this output shaft, so that the ball or disc that is the valve body is transmitted. Was opening and closing.

  However, the valve actuator with the built-in speed reduction mechanism has a structure in which a large number of spur gears are engaged and connected in multiple stages or the like, so that a wide space is provided between the output shaft and the rotation shaft of the motor. It has to be ensured, leading to an increase in the size of the actuator, a complicated structure, and a large number of parts, which has a problem in terms of cost.

In order to solve the above problem, for example, there is an actuator having a built-in reduction mechanism that can obtain a large reduction ratio with a small number of gears (see, for example, Patent Document 1).
The speed reduction mechanism is provided coaxially around an output shaft that transmits rotation to the outside of the housing, can be rotated relative to the output shaft by a motor, and has an eccentric circle that is eccentric to the rotation shaft. An annular sun internal gear that has an internal gear along its inner peripheral surface and is capable of rotating about the output shaft relative to the housing; A planetary external gear having an inner hole circle coaxial with the outer peripheral circle of the eccentric body and an outer gear on the outer periphery, provided to be extrapolated so as to be rotatable relative to the eccentric body. A rotation transmission mechanism that partially meshes with the annular sun gear and is capable of revolving along the inner circumference of the sun gear, and that transmits the rotation of the planetary outer gear to the output shaft. And against the housing of the annular sun internal gear It is those incorporating a reduction mechanism composed of a rolling and a rotary interrupting mechanism can be restrained and opened, allowing a compact actuator.

This actuator is generally provided on the output shaft side with a control switch such as a limit sensor for detecting the rotation state of the shaft in order to control the rotation of the valve. When the output shaft rotates, this control switch is turned on / off. Thus, the open / close state of the valve or the intermediate opening degree is detected. For this reason, the output shaft is normally extended above the actuator, and a plate or the like having a projecting portion is attached to the extended portion, and this plate is turned on and off by contacting the control switch.
JP 2002-115748 A

However, in a conventional actuator having a built-in planetary gear mechanism such as Patent Document 1, the external gear meshes with the internal gear so as to be inscribed, and the rotation to the output shaft is caused by the swinging motion of the external gear. Since the output is obtained, when the carrier, which is an eccentric rotating body, rotates and pushes the annular sun inner gear, a radial load due to a swinging motion is applied to the output shaft.
Therefore, a force acts on the output shaft in a direction that swings in a direction perpendicular to the axial direction, and there is a possibility that a phenomenon that the output shaft swings, that is, a so-called shaft shake occurs.

  When the output shaft fluctuates, the plate or the like provided in the extended portion of the output shaft also shakes, and this shake makes it difficult to accurately turn on and off the control switch. For this reason, it is difficult to accurately detect the rotation state of the output shaft, resulting in malfunction or the like, and during valve opening / closing operation, the valve body is controlled to open, close, or to a predetermined intermediate opening state. There was also a problem that accurate control could not be performed when trying to do so.

  Here, in an actuator incorporating a planetary gear mechanism, in order to increase speed reduction efficiency, it is common to provide a bearing such as a ball bearing between the disk that transmits the rotation of the planetary external gear to the output shaft and the housing of the actuator. However, when this actuator is mounted on a rotary valve such as a butterfly valve, it is necessary to hold the position of the valve body of the rotary valve at an intermediate opening, and therefore it is necessary to reduce the deceleration efficiency of the actuator. If the ball bearing is removed in order to achieve this, there is a problem that the vibration of the disk that transmits the rotation of the planetary external gear to the output shaft becomes large, and the shaft shake of the output shaft becomes noticeable accordingly. ing.

  The present invention has been developed to solve the conventional problems, and an object of the present invention is a valve actuator for mounting on a rotary valve such as a ball valve or a butterfly valve, and in particular, an electric motor. Is a valve actuator that can be shared with a rotary valve such as a ball valve or a butterfly valve via an intermeshing planetary gear reduction mechanism that can obtain a large reduction ratio with a small number of gears. It is possible to accurately control the angle of the valve by suppressing the shaft runout of the valve, accurately detect the open / close position of the valve, and simplify the structure to reduce the size, weight and cost. In addition, the present invention makes it possible to share a valve opening detection member such as a limit switch and a potentiometer, and other components, regardless of the magnitude of the output torque. In, yet which is excellent actuator valve economical.

  In order to achieve the above object, the present invention regulates the swing rotation of the external gear that receives the eccentric rotation from the eccentric body that rotates eccentrically in conjunction with a rotational drive source such as a motor, An actuator using a reduction gear mechanism that can output the rotation component of the external gear from the output shaft, and a support plate that supports the control shaft extending from the output shaft is fixed to the base body incorporating the reduction gear mechanism. The support plate is a valve actuator in which a swing restricting portion is disposed at a bearing portion of the control shaft and a mounting plate on which a valve opening degree detection member such as a limit switch is mounted is positioned and fixed.

  The invention according to claim 2 is the valve actuator in which a planar mounting portion is formed on the upper portion of the base body, and a support plate is positioned and fixed on the planar mounting portion.

  According to a third aspect of the present invention, a rolling bearing is used for the swing restricting portion, and the mounting plate is positioned and fixed to the support plate by fitting the inner periphery of the control shaft insertion hole of the mounting plate to the outer periphery of the rolling bearing. This is the valve actuator.

According to the present invention, the shaft shake of the control shaft extended from the output shaft can be directly suppressed, the control shaft and the valve opening degree detection member can be relatively positioned and fixed, and the valve opening degree can be reliably ensured. The detection member can be operated to perform accurate control.
Furthermore, even when the output of the actuator is different, the parts for controlling the actuator can be shared as a unit to contribute to cost reduction, and the control shaft and the valve opening degree detection member are relatively positioned and fixed. Therefore, the actuator can be controlled with high accuracy.

Further, the bearing position when the control shaft is pivotally supported can be fixed, and the positional relationship between the bearing position and the valve opening degree detection member can be fixed to further improve the accuracy.
Further, it is possible to suppress the shaft shake due to the radial load when the control shaft rotates and to sufficiently exhibit the swing control effect, and to control the swing at a low cost. The swing of the control shaft can be further suppressed to a slight extent, and the adverse effect on the valve opening degree detection member can be further suppressed.

Further, by suppressing the swing of the output shaft, the swing of the control shaft tip side can be suppressed, and the valve opening degree detection member does not malfunction due to a contact failure or the like due to the rotation of the control shaft. This control shaft is supported by a swing restricting portion provided on the support plate, and the support plate is firmly fixed to the planar mounting portion of the base body, so that the intermeshing planetary gear reduction mechanism swings. It is possible to suppress the shake of the control axis due to the above.
In particular, the shape of the planar mounting portion provided near the upper edge of the base is made thicker on the side of the intermeshing planetary gear reduction mechanism with respect to the support plate mounting bolt position. Even if the swing is transmitted to the support plate via the control shaft / swing restricting portion, the control shaft swing is suppressed while suppressing the increase in the weight of the actuator by the minimum necessary thickness of the planar mounting portion. be able to.
In addition, the valve opening degree detection member can be aligned and fixed to the support plate in a unitized state.

Next, an embodiment of the valve actuator of the present invention will be described with reference to FIGS.
FIG. 3 is a cross-sectional view showing the valve actuator of the present invention, and FIG. 4 is an exploded perspective view. As shown in the figure, reference numeral 3 denotes a rotational drive source such as a motor that can rotate bi-directionally or in one direction. The rotational drive source 3 is fixed to the upper surface side of the base body 2 by fixing means such as a bolt (not shown). ing. Reference numeral 4 denotes a drive shaft (pinion gear) of the rotational drive source 3, and this drive shaft 4 meshes with the intermediate gear 5 to transmit power from the rotational drive source 3. The intermediate gear 5 meshes with an input gear 6 provided coaxially with the output shaft 8, and the rotation from the rotational drive source 3 is input to the input gear 6 after being decelerated via the drive shaft 4 and the intermediate gear 5. .

  Reference numeral 7 denotes a reduction gear mechanism. The reduction gear mechanism 7 includes an input gear 6, an eccentric body 9, an external gear 10, a frame 11, an output shaft 8, and an intermediate gear 5 that meshes with the input gear 6. Yes. The eccentric body 9 is integrally fixed to the input gear 6, and has an eccentric portion 9 a that is eccentric with respect to the shaft center of the output shaft 8 in the amount of eccentricity e, and is interlocked with the rotation from the rotational drive source 3. The eccentric body 9 is provided so as to be eccentrically rotatable in conjunction with the rotating input gear 6.

  As described above, the valve actuator main body 1 according to the present invention regulates the oscillating rotation of the external gear 10 that oscillates in response to the eccentric rotation from the eccentric body 9 that rotates eccentrically in conjunction with the rotation drive source 3. In this embodiment, the reduction gear mechanism 7 capable of outputting the rotation component of the external gear 10 from the output shaft 8 is used. A valve opening degree detection member 21 such as a limit switch is provided on the base body 2 incorporating the reduction gear mechanism 7. The mounted mounting plate 22 is positioned and fixed, and the mounting plate 22 is provided with a swing restricting portion 24 at the bearing portion of the control shaft 23 extending from the output shaft 8. In this embodiment, the control shaft is made of chromium molybdenum steel, the mounting plate is made of steel plate, and the base plate is made of aluminum die cast.

  The valve opening degree detection member 21 is provided so that the contact point can be turned on and off according to the rotation of a limit switch cam 25 that is coaxially attached to a control shaft 23 extended from the output shaft 8, and the valve body 26 is opened or closed, or intermediately opened. The degree is detected. Reference numeral 22 a denotes an attachment portion, and this attachment portion 22 a is provided on the attachment plate 22 in a protruding shape. The valve opening degree detection member 21 is attached to the attachment plate 22 while the attachment portion 22a is inserted into the attachment hole 21a provided in the valve opening degree detection member 21, and is fixed by a retaining ring 28 from above. The lever opening degree detection member 21 is fixed.

The swing restricting portion 24 may be configured to restrict the swing of the control shaft 23 by mounting a bearing bush on one or both of the support plate 27 that supports the shaft of the intermediate gear 5 in addition to the mounting plate 22. In the embodiment, the swinging is restricted by a bearing bush mounted on the mounting plate 22. The bearing bush (swing restricting portion) 24 is preferably formed as an integral plain bearing with a low frictional resistance, such as PTFE, but a rolling bearing may be used.
Even if the shaft center position of the control shaft 23 changes due to an output change or the like, the position of the control shaft 23 can be changed by changing the mounting position of the mounting plate 22 with the pin 29 and the fixing member 30 described later. Thus, the valve opening degree detection member 21 can be provided at an appropriate position. As described above, the mounting plate 22 provided with the valve opening degree detection member 21 can be unitized, and the unitized one can be used in common for actuators having different outputs. Therefore, it is necessary to redesign the entire actuator. Absent.
After the mounting plate 22 is mounted, the swing restricting portion 24 eliminates shaft shake between the output shaft 8 and the mounting plate 22, and the rotation state of the control shaft 23 is accurately determined by the valve opening degree detection member 21 mounted on the mounting plate 22. Can be detected. The mounting plate 22 has a function of pressing down the control shaft 23 from above.

  Reference numeral 29 denotes a pin. When fixing the mounting plate 22 to the base body 2, first, the pin 29 is used to temporarily fix and position the mounting plate 22 diagonally as shown in FIG. What is necessary is just to fasten and fix with the fixing members 30, such as a volt | bolt. Therefore, even when the position of the control shaft or the like is changed due to the increase in the size of the actuator, it is possible to obtain an optimum bearing position with less shaft runout. When the mounting plate 22 is provided in another actuator, the mounting plate 22 can be mounted and fixed at an arbitrary position by changing the positions of the pin hole 29a and the female screw 30a provided in the base body 2. .

FIG. 5 is a schematic plan view of the valve actuator of the present invention. In the figure, the shape of the mounting plate 22 can be changed according to the mounting position of the rotary drive source 3, so that the combination of gears and the volume change due to the change in the reduction gear ratio of the reduction gear mechanism 7. Even if the position of the intermediate gear 5 is changed, the shape of the mounting plate 22 is changed so that the position of the rotational drive source 3 is such that the drive shaft 4 can mesh with the position of the intermediate gear 5. Thus, the rotational drive source 3 can be attached at a desired position.
In FIG. 4, 31 is a capacitor, 32 is a terminal block, 33 is a terminal box for storing the terminal block 32, and a gasket 34 that can be tightly sealed after the terminal block 32 is stored in the terminal box 33. The terminal box cover 35 is secured with bolts 36 in a state where the pin is sandwiched. Further, the terminal box 33 is attached to the base body 2 while being tightly sealed by the gasket 37.

  Here, the main components constituting the reduction gear mechanism 7 will be described with reference to FIGS. 1 to 3. The external gear 10 is combined with the outer peripheral surface side of the eccentric body 9 via a bearing 15. 10 is provided so as to be eccentrically rotated by receiving the eccentric rotation from the eccentric body 9. The tooth profile of the external gear 10 is formed as a curve composed of an epitrochoid parallel curve.

  The frame body 11 is formed in an appropriate shape such as a circular shape or a rectangular shape, and is formed integrally with the base body 2 for housing the reduction gear mechanism 7. In this embodiment, the frame body 11 is the inner peripheral side. The internal gear 11a is formed with an internal tooth 11a having an arc tooth profile. The frame 11 meshes with the external gear 10 at the internal teeth 11a, and is provided so that the external gear 10 can swing and rotate by restricting the eccentric rotation of the external gear 10.

  The output shaft 8 is fixed to the flange portion 18 so as to be integrally rotatable. Reference numeral 17 denotes a fitting hole provided in the flange portion 18. One side of the inner pin 16 formed in a rod shape is inserted into the fitting hole 17. Further, the other side of the inner pin 16 is loosely fitted in a through hole 10 b provided through the external gear 10 so that the external gear 10 and the flange portion 18 are overlapped.

The rotational movement of the external gear 10 is converted into the rotational movement of the output shaft 8 fixed to the flange portion 18 by the action of the inner pin 16 rolling in the through hole 10b. 10 is provided so that the rotation component of the external gear 10 can be output.
Reference numeral 20 denotes a valve stem, and a valve valve body 26 is rotatably connected from the output shaft 8 through the valve stem 20.

During the opening / closing operation of the valve, when rotation from the rotational drive source 3 is transmitted to the input gear 6 via the drive shaft 4 and the intermediate gear 5, the eccentric body 9 integrated with the input gear 6 rotates. When the eccentric body 9 rotates, the eccentric portion 9a rotates eccentrically, and this eccentric rotation is transmitted to the external gear 10 via the bearing 15, and the external gear 10 starts eccentric rotation.
The external gear 10 revolves at high speed around the axis of the output shaft 8 by the rotation of the eccentric body 9 and simultaneously tries to rotate at low speed. However, the frame 11 and the internal teeth 11a meshing with the external gear 10 are used. This rotation is restricted by the combination of the above, and the external gear 10 swings and rotates so as to be inscribed in the internal teeth 11a, and only the decelerated rotation component of the external gear 10 is extracted and transmitted to the output side. it can.

  When the external gear 10 swings and rotates, the inner pin 16 then tries to roll in the through hole 10b, and the external gear 10 is connected to the output shaft 8 interlocked with the external gear 10 via the inner pin 16. , And the output shaft 8 can be rotated at a reduced speed. At this time, the output shaft 8 is subjected to a force for swinging by the swinging rotation of the external gear 10, but the swing is restricted by attaching the control shaft 23 in a state where the clearance is reduced by the bearing bush 24. And rotate it.

Next, the operation of the present invention will be specifically described.
The valve actuator of the present invention positions and fixes a mounting plate 22 on which a valve opening degree detection member 21 such as a limit switch is mounted on a base body 2 incorporating a reduction gear mechanism 7, and the mounting plate 22 includes the output shaft. Since the swing restricting portion 24 is disposed in the bearing portion of the control shaft 23 extended from 8, the gap between the control shaft 23 and the swing restricting portion 24 is reduced as much as possible to prevent shaft shake. The rotation state when the control shaft 23 extended from the output shaft 8 rotates can be accurately detected by the valve opening degree detection member 21, and the rotation operation of the valve body 26 can be accurately performed without causing malfunction. Can be controlled.

FIG. 6 is a partially enlarged cross-sectional view showing another embodiment of the valve actuator in the present invention, and FIG. 7 is an exploded perspective view thereof. In addition, the same location as above-mentioned embodiment is represented by the same code | symbol, and the description is abbreviate | omitted.
This valve actuator regulates the rotational rotation of the external gear 10 that receives the eccentric rotation from the eccentric body 9 that rotates eccentrically in conjunction with the rotational drive source 3 such as a motor, and rotates the external gear 10. In the actuator using the reduction gear mechanism 7 capable of outputting the rotation component of the gear 10 from the output shaft 8, the steel plate is made by bearing the control shaft 23 extended from the output shaft 8 on the base body 2 incorporating the reduction gear mechanism 7. The support plate 39 is fixed, and a mounting plate 40 on which the valve opening degree detection member 21 such as a limit switch is mounted is positioned and fixed on the support plate 39. The mounting plate 40 extends from the output shaft 8. A swing restricting portion (bearing bush) 24 is disposed at the bearing portion of the control shaft 23.

In this actuator, the mounting plate 22 with the valve opening degree detection member 21 attached thereto is fixed to the support plate 27 in FIG. 4, and these are controlled to swing by the swing restricting portion 24. Positioning of the control shaft 23 extended to the output shaft 8 and the valve opening degree detection member 21 can be ensured, and the swinging restriction part 24 can suppress fluctuations between the control shaft 23 and the valve opening degree detection member 21. .
The bearing bush 24 is mounted so that the support plate 39 and the mounting plate 40 are inserted, and the bearing bush 24 regulates the swinging of both the support plate 39 and the mounting plate 40. If it does in this way, it will become possible to attach the valve opening degree detection member 21 to arbitrary positions in the state where the positional relationship between the valve opening degree detection member 21 and the control shaft 23 is appropriate.
Therefore, this actuator is particularly effective in the case of a large actuator having a large rotational output.

Furthermore, in the case of a large actuator with a large rotational output, the swing restricting portion may be replaced with a bearing bush, and a rolling bearing 24 'as shown in FIG. 9 may be used. In this case, the rolling bearing 24 ′ is attached to the support plate 39 fixed to the base body 2 with bolts, and the inner periphery of the control shaft insertion hole 40 a of the mounting plate 40 is fitted to the outer periphery of the rolling bearing 24 ′. .
In the present embodiment, the fit between the rolling bearing 24 ′ and the support plate 39 is set tightly, while the fit between the rolling bearing 24 ′ and the mounting plate 40 is set slightly looser than the fit with the support plate 39. Thus, the swing of the control shaft 23 is suppressed by the support plate 39 via the rolling bearing 24 ′ and is not transmitted to the mounting plate 40.
Therefore, according to the actuator of the present invention, the swing of the control shaft 23 is suppressed by the support plate 39 via the swing restricting portion 24, and the valve opening degree detection member is detected by the mounting plate 40 positioned on the support plate 39. 21 is positioned, the displacement of the relative position between the cam member 25 attached to the control shaft 23 and the valve opening degree detection member 21 fixed to the attachment plate 40 can be reduced. The opening can be accurately detected.

In the embodiment shown in FIG. 9, a transparent or semi-transparent resin hemispherical valve opening cover 50 such as ABS is inserted from the inside of the actuator cover 1a and fixed to the cover 1a with a bolt 50c and a retainer 50d. It has a structure to do. In this structure, since the bolt 50c does not protrude from the upper surface of the actuator cover, the bolt does not interfere during manual operation of the actuator, and the appearance is improved. The valve opening plate mounted on the upper part is made visible from the outside of the actuator.
Therefore, according to this actuator, the swing of the control shaft 23 is small, the valve opening degree of the valve can be accurately recognized, and the valve opening plate mounted on the upper part of the control shaft 23 and the valve opening fixed to the actuator cover 1a. Even if the clearance with the degree cover 50 is set small and the valve opening portion is made compact, both parts do not interfere with each other due to the shake of the control shaft.

  In the embodiment of FIG. 9, the control shaft 23 is a separate body, and the upper control shaft 23 is screwed to the lower control shaft 23 a extended to the output shaft 8. Since processing can be performed from a material having the minimum necessary diameter without using the material of the large-diameter output shaft 8, the cost of the material and processing can be reduced. Also, a plurality of types of control shafts 23 are prepared by attaching a number of cam members 25 corresponding to the specifications of the actuator (for example, two limit switches, four, six, etc.) to the control shaft 23 in advance. Thus, when assembling the actuator, it is only necessary to connect the control shaft 23 on which the required number of cam members 25 are mounted to the lower control shaft 23a extended to the output shaft 8, and the actuator according to the specifications can be shortened appropriately. Can be assembled in time.

Further, as shown in FIG. 8, a planar mounting portion 38 can be formed on the upper portion of the base body, and the support plate 39 or the mounting plate 22 can be positioned and fixed on the planar mounting portion 38.
The control shaft 23 is supported by the swing restricting portion 24 provided on the support plate 39, and the support plate 39 is firmly fixed to the planar mounting portion 38 of the base body 2. The swing of the control shaft 23 due to the swing of the speed reduction mechanism can be suppressed. In particular, the shape of the planar mounting portion 38 provided near the upper edge of the base is made thicker on the side of the intermeshing planetary gear reduction mechanism with respect to the female screw position 38a into which the support plate mounting bolt is screwed. As a result, even if the swing is transmitted to the support plate 39 via the control shaft 23 and the swing restricting portion 24, the weight of the actuator is suppressed by the minimum necessary thickness of the planar mounting portion 38. However, the shake of the control shaft 23 can be suppressed.

  Although not shown in the drawings, as still another invention, the rotational rotation of the external gear that oscillates in response to the eccentric rotation from the eccentric body that rotates eccentrically in conjunction with a rotational drive source such as a motor is regulated, In an actuator using a reduction gear mechanism that can output the rotation component of the external gear from the output shaft, a valve opening detection member such as a limit switch is mounted on the base body incorporating the reduction gear mechanism, and extends from the output shaft. It is also possible to provide a valve actuator in which a support plate for bearing the control shaft is positioned and fixed, and a swing restricting portion is disposed on the support plate at the bearing portion of the control shaft. Is attached to the support plate at a fixed position.

Further, as shown in FIG. 10, a limit switch (valve opening degree detection member) 21 to which a connector retainer 21 b is connected via an electric wire 53 may be attached to the attachment plate 40 in advance to be unitized. Since the number of limit switches 21 varies depending on the specifications of the actuator, a plurality of types of unitized mounting plates 40 may be prepared.
At the time of assembling the actuator, the attachment plate 40 corresponding to the required specifications is attached to the support plate 39, and the connector retainer 21b is fitted into the connector base 33d fixed to the terminal block attachment plate 33c in advance, thereby The terminal block 32 on the mounting plate and the limit switch 21 are connected in a state in which energization is possible, and the assembly work of the limit switch 21 to the actuator is completed.
Thus, the valve opening degree detection member 21 including a limit switch or the like can be configured as a unit, and the assembly work of the actuator can be performed accurately and easily.

  Here, as a structure for suppressing the swing of the control shaft above the speed reduction mechanism, a structure in which a vibration restricting portion for supporting the control shaft is arranged at the position of the control shaft insertion hole of the actuator cover is also conceivable. Since the radial load applied to the bearing is received by the actuator cover, the strength of the cover itself and the bonding strength between the cover and the base must be secured, and the cover must be accurately positioned with respect to the base. Since new improvements such as points are necessary, it is optimal to arrange the swing restricting portion on the mounting plate or the support plate as described above.

  Next, as a comparative example, in FIGS. 3 and 6, the actuator having the structure without the swing restricting portion of each embodiment has the same height as the tip of the control shaft and the upper edge of the base body directly below the support plate (side surface of the actuator case). The amplitude was measured at each position. The results are shown in Table 1. In addition, the actuator outputs 500 kgf · cm and 2000 kgf · cm, respectively.

これに対し、揺動規制部２４を設けた図３と図６の各実施形態においては、制御軸先端の振幅実測値は、それぞれ０．２ｍｍ以下に抑制された。

On the other hand, in each of the embodiments of FIGS. 3 and 6 in which the swing restricting portion 24 is provided, the actual measured amplitude value of the control shaft tip is suppressed to 0.2 mm or less.

The present invention relates to a valve actuator for mounting on a rotary valve such as a ball valve or a butterfly valve, and in particular, an electric motor or the like as a power source, and a rotary valve such as a ball valve or a butterfly valve via a speed reduction mechanism. In an actuator with a structure that rotates the valve shaft, it is possible to accurately control the angle of the valve during electric operation and manual operation, and limit switches, potentiometers, etc., regardless of the magnitude of the output torque. It is a compact and highly economical valve actuator that can share the valve opening degree detection member and other components, and can accurately detect the opening / closing position of the valve.
In addition to the rotary valve, the present invention can also be applied to devices that are driven to rotate.

FIG. 3 is an exploded perspective view of an intermeshing planetary gear speed reduction mechanism built in the valve actuator according to the present invention. It is a cross-sectional view of the intermeshing planetary gear reduction mechanism built in the valve actuator in the present invention. It is front sectional drawing of the actuator for valves in this invention. FIG. 4 is an exploded perspective view of FIG. 3. It is the schematic plan view which showed the actuator for valves of this invention. It is the partially expanded sectional view which showed other embodiment of the actuator for valves. FIG. 7 is an exploded perspective view of the actuator of FIG. 6. It is the schematic plan view which showed the planar mounting part. It is front sectional drawing which showed other embodiment of the actuator for valves. It is the perspective view which showed other embodiment of the actuator for valves.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Actuator main body 2 Base body 3 Rotation drive source 7 Reduction gear mechanism 8 Output shaft 9 Eccentric body 10 External gear 21 Valve opening degree detection member 22, 40 Mounting plate 23 Control shaft 24 Oscillation control part 27 Support plate 38 Planar mounting Place 40a Control shaft insertion hole

Claims (3)

  Regulates the rotational rotation of the external gear that rotates in response to the eccentric rotation from the eccentric body that rotates eccentrically in conjunction with a rotational drive source such as a motor, and outputs the rotation component of this external gear from the output shaft. In an actuator using a possible reduction gear mechanism, a support plate bearing a control shaft extending from an output shaft is fixed to a base body incorporating the reduction gear mechanism, and this support plate is attached to a bearing portion of the control shaft. A valve actuator characterized in that a swing restricting portion is disposed and a mounting plate on which a valve opening degree detection member such as a limit switch is mounted is positioned and fixed.   The valve actuator according to claim 1, wherein a planar placement portion is formed on an upper portion of the base body, and the support plate is positioned and fixed on the planar placement portion. 2. A rolling bearing is used for the swing restricting portion, and the mounting plate is positioned and fixed to the support plate by fitting the inner periphery of the control shaft insertion hole of the mounting plate to the outer periphery of the rolling bearing. The actuator for a valve as described.

Images