JP4122235B2 - Valve drive device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a drive device for a valve body of a valve such as a ball valve or a butterfly valve, and has a particularly high self-locking function, and at the same time, can improve the rotational efficiency of the entire device, and is small and low cost. The present invention relates to a valve driving apparatus.
[0002]
[Prior art]
Conventionally, a valve using a ball valve, a butterfly valve, or the like is widely known as a valve that is installed in a piping line of a building facility or a water treatment facility, and opens and closes a flow path or adjusts a flow rate. Many manual or electric drive devices have been proposed for driving the motor. As such a drive device, a worm gear mechanism is most commonly applied to the drive device, but besides the worm gear mechanism, a drive device using an eccentric planetary gear mechanism capable of saving space is also proposed. (For example, refer to Patent Document 1).
[0003]
In these valve drive devices, it is necessary to appropriately adjust the amount of fluid flowing through the pipe line, etc., so that the valve body is required to be smoothly rotated during rotation, while the valve body is connected to the pipe when rotation is stopped. In order to receive a strong load from the fluid flowing through the passage or the like, a function for preventing the valve body from rotating in the reverse direction (reverse rotation preventing function) is also required.
[0004]
[Patent Document 1]
JP 2000-193136 A
[Problems to be solved by the invention]
However, when the worm gear mechanism is applied to the valve drive device, the rotation in the reverse direction is restricted due to its structure, so that a high anti-reverse effect (self-locking function) can be obtained, but during the rotation operation (especially The rotation efficiency is low at the time of rotation start-up, and there is a problem that the power consumption becomes large particularly when used in an application that is frequently operated by a motor.
[0006]
On the other hand, when the eccentric planetary gear mechanism is applied to the valve drive device, the rotational efficiency is higher than that of the worm gear mechanism, but the structure is easy to rotate in the reverse direction, so it is weak against the load applied to the valve body. There was a problem.
[0007]
That is, if the rotational resistance of the members constituting the speed reduction mechanism is simply increased, the reverse rotation prevention function can be improved, but at the same time, the rotational resistance in the driving direction also increases, and the rotational efficiency of the entire apparatus is deteriorated. End up. On the other hand, it is possible to increase the rotation efficiency of the entire device by lowering the rotational resistance of the members constituting the speed reduction mechanism, but the self-locking functionality and rotational smoothness are related to each other, so simply If the rotational resistance is reduced and the rotational efficiency is increased, naturally the structure is easy to rotate in the reverse drive direction, and the self-locking function is lowered.
[0008]
The present invention has been made to solve such a problem, and has a small self-locking function, and at the same time, can improve the rotation efficiency of the entire apparatus, and is small and low cost. It aims at providing a valve drive device.
[0009]
[Means for Solving the Problems]
The present invention includes a valve drive mechanism capable of driving a valve body via a valve stem, and a speed reducer that transmits the rotation of the input shaft to the output shaft at a reduced speed, and the output shaft and the valve of the speed reducer In the valve drive device that can drive the valve body by connecting a rod, the speed reduction mechanism of the speed reducer includes a first external gear and a first internal gear having a slight difference in the number of teeth, A first internal mesh planetary gear mechanism in which the first external gear is rotatably incorporated in the first internal gear in an eccentric inward meshing manner, and the first internal gear between the same input shaft and output shaft. A second external gear and a second internal gear that are arranged in parallel with the meshing planetary gear mechanism on the power transmission path and have a slight difference in the number of teeth are provided, and the second external gear is connected to the second internal gear. And a second intermeshing planetary gear mechanism which is incorporated in the inside of the toothed gear so as to be freely rotatable in the inscribed intermeshing mesh. 1, wherein the first second internally meshing planetary gear mechanism, by which gave a difference each rotation resistance of the second external gear is obtained by solving the above problems.
[0010]
According to the present invention, two types of internally meshing planetary gear mechanisms having different power transmission characteristics by providing a difference in rotational resistance of external gears as a speed reduction mechanism of a reduction gear are provided on a power transmission system path. Since it is provided in parallel, it is possible to transmit the power from the valve drive mechanism input to the speed reducer to the valve stem and the valve body via power transmission paths having different power transmission characteristics. Therefore, the characteristics of the speed reducer can be changed depending on the characteristics of the internal meshing planetary gear mechanism to be combined, and characteristics suitable for the valve driving device can be obtained.
[0011]
For example, the first intermeshing planetary gear mechanism is a mechanism in which the rotational resistance of the rotating system is large, the rigidity is low, and the backlash amount is small, and the second intermeshing planetary gear mechanism is rotated. Provided with a mechanism that has low rotational resistance, high rigidity, and a large backlash amount, a valve drive device that has a high self-locking function and can simultaneously improve the rotational efficiency of the entire device is provided. It becomes possible. Therefore, even when the valve body is subjected to a strong load by the fluid flowing through the pipe line or the like, the high self-locking function can prevent the valve body from rotating in the anti-drive direction. At the time of opening and closing the body, the valve body can be moved with high efficiency by high rotational smoothness, and the operability can be improved. Moreover, since a special mechanism such as a brake is not required as the reverse rotation prevention mechanism, the valve drive device can be reduced in size and cost.
[0012]
In the present invention, there is no particular limitation as to how the rotational resistance of the external gear is specifically differentiated. For example, the first and second external gears are connected to the input shaft. Incorporating in an oscillating manner via an eccentric body provided on the outer periphery of the input shaft, the sliding modes of the sliding portions of the eccentric body and the first and second external gears are different. By doing so, it becomes possible to give a difference in the rotational resistance of the first and second external gears.
[0013]
In addition, each of the internal teeth of the first and second internal gears is constituted by a plurality of cylindrical pins, and the holding manner of the cylindrical pins is made different, or the first and second external gears are Each of the first and second external gears is loosely fitted into an inner pin hole formed in each of the tooth gears, and is supported by a carrier that is maintained in a fixed state. If the external gear arranged on the carrier side has a higher rigidity by absorbing the rotation component, the first and second intermeshing planetary gear mechanisms have different rigidity. Thus, the characteristics of the speed reducer can be changed, and characteristics suitable for the valve driving device can be obtained.
[0014]
Further, if the backlash amount of the first intermeshing planetary gear mechanism and the backlash amount of the second intermeshing planetary gear mechanism with respect to the input shaft and the output shaft are respectively different, deceleration is also caused by the difference in backlash amount. The characteristics of the machine can be changed, and characteristics suitable for the valve driving device can be obtained.
[0015]
If the rotation direction of the input shaft is the same as the rotation direction of the valve body, the rotation direction of the operation handle of the valve drive device and the rotation direction of the valve body coincide with each other. It is possible to improve.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0017]
FIG. 1 is a side sectional view of a valve driving device 300 according to an example of an embodiment of the present invention.
[0018]
The valve driving device 300 includes a handle (valve driving mechanism) 310 and a speed reducer 340 accommodated in a casing 316 including upper and lower casings 312 and 314. The valve driving device 300 can drive and rotate a valve body (not shown) provided on the valve rod 350 by a handle 310 by connecting the valve rod 350 to the output shaft 306 of the speed reducer 340.
[0019]
The handle 310 is connected to the input shaft 302 of the speed reducer 340, and the input shaft 302 can be rotationally driven by rotating the handle 310 about the axis L1. An opening guide 318 indicating the opening degree of the valve body is attached to the upper end of the input shaft 302, and the opening degree can be adjusted while checking the opening degree of the valve body from above. ing.
[0020]
The speed reducer 340 includes a first intermeshing planetary gear mechanism 100, a second intermeshing planetary gear mechanism 200, and an input shaft 302 common to the first and second intermeshing planetary gear mechanisms 100, 200. A carrier 304 and an output shaft 306. The speed reducer 340 can transmit the power input from the input shaft 302 to the valve rod 350 via the first and second intermeshing planetary gear mechanisms 100 and 200 and the output shaft 306.
[0021]
The input shaft 302 is formed of a hollow shaft having a hollow portion 302a, is disposed coaxially with the output shaft 306, and is rotatable about the same axis L1 as the valve rod 350.
[0022]
The carrier 304 is maintained in a fixed state by the upper casing 312, and an inner pin 346 is integrally provided on the carrier 304. The inner pins 346 are loosely fitted in inner pin holes 102a and 202a provided in first and second external gears 102 and 202, which will be described later.
[0023]
Similar to the input shaft 302, the output shaft 306 is formed of a hollow shaft having a hollow portion 306a, and is rotatable about the same axis L1 as the input shaft 302.
[0024]
Further, between the input shaft 302 and the output shaft 306, a first intermeshing planetary gear mechanism 100 and a second intermeshing planetary gear mechanism 200 having the same speed change mechanism are arranged in parallel on the power transmission path. Yes.
[0025]
Note that “arranged in parallel on the power transmission path” means that there are two paths (first and second intermeshing planets) through which power can be transmitted between the input shaft 302 and the output shaft 306 which are common members. It means that the gear mechanism 100, 200) is arranged. By the way, “preparing in series on the power transmission path” means passing through another path after obtaining a path.
[0026]
2 and 3 are views showing the first intermeshing planetary gear mechanism 100 and the second intermeshing planetary gear mechanism 200, respectively. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a sectional view taken along line III-III in FIG.
[0027]
As shown in FIGS. 1 and 2, the first internally meshing planetary gear mechanism 100 includes a first external gear 102 and a first internal gear 104 having a slight difference in the number of teeth, an eccentric body 106, and a sliding bearing. (Sliding part) 110.
[0028]
The eccentric body 106 has an outer periphery that is eccentric with respect to the axis L1. The eccentric body 106 is provided on the outer periphery of the input shaft 302 with a predetermined phase difference (180 ° in this example) from an eccentric body 206 of a second inscribed meshing planetary gear mechanism 200 described later.
[0029]
The first internal gear 104 has a structure in which a cylindrical outer pin 104a is fitted in a plurality of circular grooves 306a formed on the inner peripheral surface of the output shaft 306, and these outer pins 104a form internal teeth. . A ring-shaped groove 108 is formed in the output shaft 306 in the outer peripheral direction of the first internal gear 104.
[0030]
The first external gear 102 has external teeth such as a trochoidal tooth shape and an arc tooth shape on the outer periphery, and is eccentrically incorporated in the inner pin 104a of the first internal gear 104 so as to be rotatable in an eccentric manner. Yes. The first external gear 102 is fitted to the eccentric body 106 via a slide bearing 110 provided between the first external gear 102 and the eccentric body 106, and the eccentric body 106 is rotated. And swingable. Further, the first external gear 102 is provided with a plurality of inner roller holes 102a, and an inner pin 346 passes through each roller hole 102a. As shown in FIG. 1, one end 346 a (upper side in the drawing) of the inner pin 346 is cantilevered by the carrier 304.
[0031]
On the other hand, as shown in FIGS. 1 and 3, the second internally meshing planetary gear mechanism 200 includes a second external gear 202 and a second internal gear 204 having a slight difference in the number of teeth, an eccentric body 206, And a roller bearing (sliding portion) 210.
[0032]
The eccentric body 206 has an outer periphery that is eccentric with respect to the axis L1. The eccentric body 206 is provided on the outer periphery of the input shaft 302 with a predetermined phase difference from the eccentric body 106 of the first inscribed mesh planetary gear mechanism 100.
[0033]
The second internal gear 204 has a structure in which outer pins 204a are fitted into a plurality of circular grooves 306a formed on the inner peripheral surface of the output shaft 306, and these outer pins 204a form inner teeth.
[0034]
The second external gear 202 has external teeth such as a trochoidal tooth shape and an arc tooth shape on the outer periphery, and is incorporated in an outer side of the outer pin 204a of the second internal gear 204 so as to be able to rotate eccentrically in intermeshing manner. Yes. Further, the second external gear 202 is fitted to the eccentric body 206 via a roller bearing 210 provided between the second external gear 202 and the eccentric body 206, and the eccentric body 206 is rotated. Along with this, it can swing and rotate. Further, the second external gear 202 is provided with a plurality of inner roller holes 202a, and an inner pin 346 passes through each roller hole 202a.
[0035]
As shown in FIG. 1, the inner pin 346 passes through each roller hole 102 a of the first external gear 102 and each roller hole 202 a of the second external gear 202, respectively. The rotational component of the two external gears 202 can be absorbed. The second external gear 202 is disposed on the carrier 304 side of the first external gear 102, that is, at a position near the one end 346 a of the inner pin 346 that is cantilevered by the carrier 304.
[0036]
Further, in the first intermeshing planetary gear mechanism 100, the clearance S11 between the eccentric body 106 and the sliding bearing 110, the clearance S12 between the sliding bearing 110 and the first external gear 102, the inner pin 346 and the first external gear 102 The clearance S13 between the first external gear 102 and the first internal gear 104 is the clearance S21 between the eccentric body 206 and the bearing 210 in the second intermeshing planetary gear mechanism 200, the roller bearing 210 and the second It is designed to be smaller than the clearance S22 between the external gear 202, the clearance S23 between the internal pin 346 and the second external gear 202, and the clearance S24 between the second external gear 202 and the second internal gear 204 ( S11 <S21, S12 <S22, S13 <S23, S14 <S24). In addition, the magnitude relationship of all the gaps does not necessarily need to be like this, and it is sufficient that the sum is so.
[0037]
Therefore, the backlash amount of the first internally meshing planetary gear mechanism 100 with respect to the input shaft 302 and the output shaft 306 is smaller than the backlash amount of the second internally meshing planetary gear mechanism 200.
[0038]
Next, returning to FIG. 1, the operation of the valve driving device 300 according to the example of the embodiment of the present invention will be described.
[0039]
When the handle 310 is rotated, the input shaft 302 rotates about the axis L1, and the eccentric bodies 106 and 206 provided on the input shaft 302 rotate eccentrically. Due to the rotation of the eccentric bodies 106 and 206, the first and second external gears 102 and 202 mounted on the eccentric outer periphery try to swing and rotate around the input shaft 302. Since the rotation is constrained, the first and second external gears 102 and 202 only swing while inscribed in the first and second internal gears 104 and 204.
[0040]
By the swing of the first and second external gears 102 and 202, the first and second external gears 102 and 202 are moved in the first and second external gears 102 and 202 every time the input shaft 302 is rotated (every rotation of the input shaft 302). The two internal gears 104 and 204 rotate by an amount corresponding to the difference in the number of teeth from the first and second external gears 102 and 202, and the rotation of the first and second internal gears 104 and 204 is the output shaft 306. Is transmitted, and deceleration is realized.
[0041]
In the reduction gear 340 of the valve drive device 300 according to the example of the embodiment of the present invention, the first and second internal gears 104 and 204 and the output shaft 306 are rotated while the carrier 304 is maintained in a fixed state. By doing so, the rotation direction of the input shaft 302 and the rotation direction of the output shaft 306 are matched. As a result, the rotation direction of the handle 310 and the rotation direction of the valve body can be made the same, and it is easy to operate sensibly and the operability is improved.
[0042]
Finally, the power transmitted to the output shaft 306 causes the valve body to be rotationally driven through the valve rod 350 connected to the output shaft 306.
[0043]
The valve driving device 300 according to the example of the above embodiment includes the first internally meshing planetary gear mechanism 100 and the second internally meshing planetary gear mechanism 200, which are power transmission mechanisms having the same speed change mechanism, in parallel. (1) Rotational resistance, (2) Rigidity, (3) of rotating members (rotating systems) such as the first and second external gears 102, 202 and the first and second internal gears 104, 204 in the power transmission mechanism of ▼ By using backlash as an element of power transmission characteristics, and providing each element with a difference, the difference in power transmission characteristics of the first intermeshing planetary gear mechanism 100 and the second intermeshing planetary gear mechanism 200 is realized. .
[0044]
That is, regarding the “rotation resistance”, the sliding bearing 110 is disposed at the sliding portion between the first external gear 102 and the eccentric body 106 of the first intermeshing planetary gear mechanism 100, while the second intermeshing meshing. By disposing a roller bearing 210 at the sliding portion between the second external gear 202 and the eccentric body 206 of the planetary gear mechanism 200, the first internally meshing planetary gear mechanism 100 and the second internally meshing planetary gear mechanism 200 are arranged. There is a difference in the rotational resistance. Thus, since the rotational resistance of each power transmission mechanism is different, the first intermeshing planetary gear mechanism 100 has characteristics that the rotational resistance is high and the reverse rotation prevention functionality is high. The two intermeshing planetary gear mechanism 200 has characteristics that the rotational resistance is small and the rotational smoothness is high.
[0045]
As for “rigidity”, a ring-shaped groove 108 is formed in the output shaft 306 in the outer peripheral direction of the first internal gear 104 of the first internal mesh planetary gear mechanism 100, while the second internal mesh. The groove is not formed in the outer peripheral direction of the second internal gear 204 of the planetary gear mechanism 200, and the entire outer pin 204a is directly held by a plurality of circular grooves 306a formed on the inner peripheral surface of the output shaft 306. Thus, a difference is provided in the rigidity of the rotation systems of the first inscribed mesh planetary gear mechanism 100 and the second inscribed mesh planetary gear mechanism 200. That is, when a force is applied to the outer pin 104a of the first internal gear 104 toward the output shaft 306 (outside in the radial direction), the ring-shaped groove 108 is formed. The pin 104a can be bent toward the output shaft 306, whereas the outer pin 204a of the second internal gear 204 is restricted from being bent toward the output shaft 306. Further, the second external gear 202 is arranged closer to the carrier 304 than the first external gear 102, that is, closer to one end 346 a of the inner pin 346 that is cantilevered by the carrier 304. A difference is provided in the rigidity of the intermeshing planetary gear mechanism 100 and the second intermeshing planetary gear mechanism 200. As described above, since the rigidity of each power transmission mechanism is different, the first inscribed mesh planetary gear mechanism 100 has a large deformation amount (low rigidity) of each member with respect to the transmission torque as a whole, and the power transmission capacity. The second intermeshing planetary gear mechanism 200 has the characteristics that the deformation amount of each member with respect to the transmission torque is small (high rigidity) and the power transmission capacity is high. ing.
[0046]
Further, regarding “backlash”, the clearance S11 between the eccentric body 106 and the sliding bearing 110 in the first internally meshing planetary gear mechanism 100, the clearance S12 between the sliding bearing 110 and the first external gear 102, the inner pin 346 and the first The clearance S13 between the first external gear 102 and the clearance S14 between the first external gear 102 and the first internal gear 104 is a clearance S21 between the eccentric body 206 and the bearing 210 in the second internally meshing planetary gear mechanism 200. The clearance S22 between the roller bearing 210 and the second external gear 202, the clearance S23 between the inner pin 346 and the second external gear 202, and the clearance S24 between the second external gear 202 and the second internal gear 204, respectively. By designing it to be small, a difference is provided in the amount of backlash between the first internally meshing planetary gear mechanism 100 and the second internally meshing planetary gear mechanism 200. As described above, since the backlash amount of each power transmission mechanism is different, the first intermeshing planetary gear mechanism 100 is capable of responding to the movement of the input shaft 302 (torque fluctuation) and the output shaft. The second inscribed mesh planetary gear mechanism 200 has a large amount of backlash, and the movement of both the input shaft 302 and output shaft 306 ( (Torque fluctuation) has a characteristic of slow response.
[0047]
Therefore, the valve driving device 300 has a small rotational resistance and a first intermeshing planetary gear mechanism 100 that is a power transmission mechanism with an emphasis on self-locking functionality, which has a large rotational resistance, a low rigidity, and a small backlash amount. In addition, the second intermeshing planetary gear mechanism 200, which is a power transmission mechanism with high rigidity and a large backlash amount, with an emphasis on rotational smoothness, is provided in parallel. As a result, immediately after the start of the valve driving device 300, the first intermeshing planetary gear mechanism 100 having a small backlash amount with respect to the input shaft 302 reacts quickly and mainly transmits power, but the first intermeshing planetary planet. Since the gear mechanism 100 has lower rigidity than the second intermeshing planetary gear mechanism 200, the reaction force cannot be supported when the applied torque increases, and the second intermeshing planetary gear mechanism 200 having higher rigidity is mainly used. Power is transmitted. Since the second internally meshing planetary gear mechanism 200 has a small rotational resistance, the overall rotational efficiency of the valve driving device 300 can be improved.
[0048]
Further, when a rotational load in the reverse direction is applied to the output shaft 306 from the valve body side (not shown), the first internally meshing planetary gear mechanism 100 with a small backlash amount with respect to the output shaft 306 reacts quickly and mainly. Although it receives a load in the reverse direction, since the first inscribed mesh planetary gear mechanism 100 has a large rotational resistance, the valve driving device 300 has a high self-locking function as a whole. Since the torque applied from the output shaft 306 side is smaller than the torque during normal operation, a sufficient reaction force can be provided only by the first intermeshing planetary gear mechanism 100 having low rigidity.
[0049]
Therefore, in the valve drive device 300 according to the example of the embodiment of the present invention, even when the valve body is subjected to a strong load by the fluid flowing through the piping or the like, the valve body is in the anti-drive direction by a high self-lock function In addition, when the valve body is opened and closed, the valve body can be moved with high efficiency by high rotational smoothness, and operability can be improved. In addition, since a special mechanism such as a brake is not required as the reverse rotation prevention mechanism, the valve driving device 300 can be reduced in size and cost.
[0050]
In the above embodiment, the valve drive mechanism is the manual handle 310, but the present invention is not limited to this.
[0051]
The reduction mechanism of the valve drive device according to the present invention includes a first external gear and a first internal gear having a slight difference in the number of teeth, and the first external gear is used as the first internal gear. A first intermeshing planetary gear mechanism that is incorporated in the inside in an eccentric manner so that it can rotate freely, and is arranged in parallel on the power transmission path between the first intermeshing planetary gear mechanism and the same input shaft and output shaft. And a second external gear and a second internal gear having a slight difference in the number of teeth, and the second external gear is incorporated into the second internal gear so as to be eccentrically intermeshingly rotatable. It is sufficient if it is composed of two intermeshing planetary gear mechanisms, and is not limited to the intermeshing planetary gear mechanism in the above embodiment. Therefore, for example, as a speed reduction mechanism for a valve drive device, an input gear is distributed to an axis parallel to the input shaft (center axis) by a gear, etc. A so-called sort-type inscribed mesh planetary gear mechanism or the like that rotates eccentrically with respect to the shaft may be applied.
[0052]
In the valve driving device 300 according to the present invention, there is no particular limitation on how the rotational resistances of the first and second external gears 102 and 202 are specifically changed. The first and second external gears are arranged by disposing sliding promotion members such as bearings and inner rollers in the sliding portions of the inner pin holes 102a and 202a of the second external gears 102 and 202 and the inner pin 346. You may give a difference in the rotational resistance of 102,202.
[0053]
Further, the difference in rigidity between the first and second intermeshing planetary gear mechanisms 100 and 200 is not limited to the example in the above embodiment, and, for example, the material of the first and second external gears 102 and 202 is changed. Accordingly, the difference in rigidity may be realized.
[0054]
【The invention's effect】
According to the present invention, it is possible to provide a valve drive device that has a high self-locking function and can simultaneously improve the rotation efficiency of the entire device.
[Brief description of the drawings]
FIG. 1 is a side sectional view of a valve driving apparatus according to an example of an embodiment of the present invention. FIG. 2 is a sectional view taken along line II-II in FIG. Sectional view [Explanation of symbols]
DESCRIPTION OF SYMBOLS 100 ... 1st internal meshing planetary gear mechanism 200 ... 2nd internal meshing planetary gear mechanism 102,202 ... External gear 104,204 ... Internal gear 106,206 ... Eccentric body 110 ... Sliding bearing 210 ... Roller bearing 300 ... Valve drive device 302 ... Input shaft 304 ... Carrier 306 ... Output shaft 310 ... Handle 312, 314 ... Casing 318 ... Opening pointer 340 ... Reducer 346 ... Inner pin 350 ... Valve rod

Claims (5)

A valve drive mechanism capable of driving a valve body via a valve stem; and a speed reducer that decelerates and transmits the rotation of the input shaft to the output shaft, and connects the output shaft of the speed reducer and the valve stem. By doing so, in the valve drive device capable of driving the valve body,
The speed reduction mechanism of the speed reducer includes a first external gear and a first internal gear having a slight difference in the number of teeth, and the first external gear is eccentrically inscribed inside the first internal gear. A first intermeshing planetary gear mechanism that is rotatably incorporated, and the first intermeshing planetary gear mechanism that is arranged in parallel on the power transmission path between the same input shaft and output shaft, and having a small number of teeth A second internal meshing planetary gear comprising a second external gear and a second internal gear having a difference, and incorporating the second external gear so as to be eccentric inward meshing rotation inside the second internal gear. With the mechanism,
The valve drive device according to claim 1, wherein the first and second external gears of the first and second intermeshing planetary gear mechanisms have different rotational resistances. In claim 1,
The first and second external gears are incorporated in the input shaft so as to be swingable via an eccentric body provided on the outer periphery of the input shaft, and the eccentric body and the first and second external gears. The valve drive device is characterized in that each sliding part has a different sliding manner. In claim 1 or 2,
The valve drive device characterized in that the internal teeth of the first and second internal gears are each constituted by a plurality of cylindrical pins, and the holding manner of the cylindrical pins is different. In any one of Claims 1 thru | or 3,
The first and second external gears are loosely fitted in inner pin holes formed respectively, and the first ends of the first and second external gears are cantilevered by the carrier maintained in a fixed state through the inner pins. And the rigidity of each member of the internal meshing planetary gear mechanism arranged on the carrier side is increased by adopting a configuration capable of absorbing the rotation component of the second external gear, and a valve drive device characterized by . A valve drive mechanism capable of driving a valve body via a valve stem; and a speed reducer that decelerates and transmits the rotation of the input shaft to the output shaft, and connects the output shaft of the speed reducer and the valve stem. By doing so, in the valve drive device capable of driving the valve body,
The speed reduction mechanism of the speed reducer includes a first external gear and a first internal gear having a slight difference in the number of teeth, and the first external gear is eccentrically inscribed inside the first internal gear. A first intermeshing planetary gear mechanism that is rotatably incorporated, and the first intermeshing planetary gear mechanism that is arranged in parallel on the power transmission path between the same input shaft and output shaft, and having a small number of teeth A second internal meshing planetary gear comprising a second external gear and a second internal gear having a difference, and incorporating the second external gear so as to be eccentric inward meshing rotation inside the second internal gear. With the mechanism,
The valve characterized in that the second intermeshing planetary gear mechanism is a mechanism in which the rotational resistance of the rotating system is smaller, the rigidity is higher, and the backlash amount is larger than that of the first intermeshing planetary gear mechanism. Drive device.

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