Electric actuator

Abstract

To provide an electric actuator that allows easy manual operation of a water supply control device in emergencies and the like.SOLUTION: An electric actuator 16 includes an actuator body 40 and a mounting section 42. The actuator body can be switched between a fixed state, where it is non-rotatably secured to the mounting section, and a rotatable state, where it can rotate 360 degrees or more around the mounting section in the circumferential direction. In the rotatable state, the actuator body can rotate around the mounting section in the circumferential direction while being prevented by a guide bolt 82 from detachment from the mounting section in the vertical direction.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to an electric actuator, and more particularly to an electric actuator that is attached to a water supply control device having a displacement mechanism for controlling water supply to or drainage from a field and operates the displacement mechanism.

Background Art

[0002] An example of a conventional water supply control device to which an electric actuator is attached is disclosed in Patent Document 1. In the technology of Patent Document 1, by attaching an electric actuator for driving the water supply control device such as a water supply faucet or a drain outlet, it is possible to remotely operate or automatically control the water management of the field. When attaching the electric actuator to the water supply control device, the valve shaft (or connecting shaft) of the water supply control device and the rotating shaft of the electric actuator are connected.

[0003] Another example of a conventional electric actuator is disclosed in Patent Document 2. The electric actuator of Patent Document 2 is an electric valve actuator that is attached to the input side of a speed reducer for driving a part-turn valve, and decelerates the rotation of a motor by a worm and a worm wheel to drive the speed reducer. In this electric actuator, a drive sleeve is provided inside the worm wheel, and an output shaft connected to the speed reducer is provided inside the drive sleeve. Further, one end side of a clutch is provided on the drive sleeve or the output shaft, and a manual handle is provided on the other end side of the clutch. The clutch is in a disengaged state when the motor is started, and is in a connected state when the motor is stopped, and the valve can be opened and closed only by rotating the manual handle when the motor is stopped.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the event of a failure of the electric actuator or the like, it is necessary to manually displace (open / close) the displacement mechanism of the water supply control device by manual operation. In the technology of Patent Document 1, when manually operating the water supply control device, it is necessary to disconnect the connection between the valve shaft (or connecting shaft) of the water supply control device and the rotating shaft of the electric actuator, and then attach a handle to the valve shaft and turn it, so it takes time to perform the manual operation.

[0006] On the other hand, in the technology of Patent Document 2, a clutch mechanism for disconnecting the motor shaft and a mechanism for transmitting the rotation of the manual handle to the rotating shaft of the electric actuator are required, so the structure of the electric actuator becomes complicated. As the structure becomes complicated, the electric actuator becomes larger and the price also increases.

[0007] Therefore, the main object of this invention is to provide a novel electric actuator.

[0008] Another object of this invention is to provide an electric actuator that can easily manually operate the water supply control device in an emergency or the like.

Means for Solving the Problems

[0009] The first invention is an electric actuator attached to a water supply control device having a displacement mechanism for controlling water supply to or drainage from a field, the electric actuator operating the displacement mechanism, and having an actuator body having a drive mechanism for driving the displacement mechanism and a main body case for housing the drive mechanism, and a mounting portion for attaching the actuator body to the water supply control device. The main body case has a first bolt hole formed at a lower end portion of the main body case and a second bolt hole formed at a lower end portion of the main body case at a height position different from the first bolt hole. The mounting portion has a side wall portion fitted to the lower end portion of the main body case, a through hole formed in the side wall portion at a position corresponding to the first bolt hole, and an annular guide groove formed in the side wall portion at a position corresponding to the second bolt hole and extending in the circumferential direction of the side wall portion. The mounting portion includes a fixing bolt screwed into the first bolt hole through the through hole and a guide bolt screwed into the second bolt hole and having a tip end engaged with the guide groove. The actuator body can be switched between a fixed state in which it is non-rotatably fixed to the mounting portion and a rotatable state in which it can rotate 360 degrees or more in the circumferential direction with respect to the mounting portion, and in the rotatable state, it can rotate in the circumferential direction with respect to the mounting portion while being prevented from coming off in the vertical direction with respect to the mounting portion by the guide bolt. In the rotatable state, by rotating the actuator main body in the circumferential direction while connecting the displacement mechanism and the drive mechanism, the displacement mechanism can be displaced. It is an electric actuator.

[0010] According to the first invention, by simply making the actuator body rotatable, the connection between the displacement mechanism of the water supply control device and the drive mechanism of the electric actuator can be released without providing a complicated mechanism such as a clutch structure in the electric actuator, and the displacement mechanism of the water supply control device can be displaced by rotating the actuator body in the circumferential direction. Therefore, the water supply control device can be easily manually operated in an emergency or the like. Further, since the actuator body can be rotated smoothly and stably, the water supply control device can be more easily manually operated.

[0011] The second invention is dependent on the first invention, and the fixing bolt is a drop-preventing bolt having a thread formed only at the tip end portion.

[0012] The third invention is dependent on the first or second invention, and the actuator body has an annular plate-shaped or rod-shaped handle portion that protrudes outward from the outer surface of the main body case.

[0013] According to the third invention, since it becomes easier to rotate the actuator body by gripping the handle portion, the water supply control device can be more easily manually operated.

Advantages of the Invention

[0014] According to this invention, the water supply control device can be easily manually operated in an emergency or the like without releasing the connection between the displacement mechanism of the water supply control device and the drive mechanism of the electric actuator, and without providing a complicated mechanism such as a clutch structure in the electric actuator.

[0015] The above objects, other objects, features, and advantages of this invention will become more apparent from the following detailed description of the embodiments with reference to the drawings.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0017] Referring to FIG. 1, an electric actuator 16 which is an embodiment of the present invention is attached to a water supply control device such as a water tap 12 and a drain port 14 installed in a field 100 to operate a displacement mechanism of the water supply control device. As will be described in detail later, the electric actuator 16 includes an actuator main body 40 and a mounting portion 42 provided below the actuator main body 40, and a connecting portion between the actuator main body 40 and the mounting portion 42 has a structure that can be switched between a fixed state and a rotatable state.

[0018] In this embodiment, the electric actuator 16 is used in a field water management system 10. Hereinafter, first, an example of the configuration of the field water management system 10 will be briefly described. However, the configuration of the field water management system 10 (such as the specific configurations of the water tap 12, the drain port 14, and the electric actuator 16) is not limited thereto and can be appropriately changed.

[0019] As shown in FIG. 1, the field water management system 10 is a field facility for performing water management of the field 100 by remote operation or automatic control based on a pre-stored program. In this embodiment, the field water management system 10 includes a water tap 12 and a drain port 14, and an electric actuator 16 is attached to each of the water tap 12 and the drain port 14. That is, as the electric actuator for driving the displacement mechanisms of the water tap 12 and the drain port 14, the electric actuator 16 having the same structure is used.

[0020] Although not shown in the figure, sensor terminals such as a water level sensor such as an ultrasonic sensor for detecting the field water level, each temperature sensor for detecting the air temperature and the water temperature, a pressure sensor for detecting the atmospheric pressure, and a soil moisture sensor for detecting the soil moisture are appropriately provided in the field 100. The sensor terminal is connected to the electric actuator 16 via wiring.

[0021] Also, in this embodiment, the field water management system 10 is a system including a plurality of cultivation areas partitioned by ridges 102. Each of the water supply taps 12 and the water outlets 14 is installed in each cultivation area, and each electric actuator 16 attached thereto is wirelessly communicably connected to a relay device (master device) by a wireless communication method conforming to a specific low-power wireless standard (920 MHz band). Then, each electric actuator 16 is wirelessly communicably connected to a remote operation terminal such as a smartphone, a tablet terminal, a PDA, and a PC owned by a user via this relay device and a management server or the like provided on the network. However, the electric actuator 16 may be configured to perform wireless communication with an external device such as a management server or a remote operation terminal without going through the relay device.

[0022] In this wireless communication, it is preferable to use cloud computing. For example, information acquired by each electric actuator 16 (information regarding the states of the water supply tap 12 and the water outlet 14 such as the valve opening degree of the water supply tap 12 and the drainage port height of the water outlet 14, and sensor information such as the field water level received from the sensor terminal) is transmitted to and stored in a cloud server which is an example of a management server at any time. The user can manage the water in the field 100 by accessing the cloud server from the remote operation terminal to check the information acquired by each electric actuator 16 and remotely operating each electric actuator 16 using the remote operation terminal.

[0023] The water supply tap 12 is a water supply device for controlling the water supply to the field 100, and has a displacement mechanism including a valve shaft and a valve body. In this embodiment, a water supply tap 12 of a type in which the valve shaft and the valve body move up and down as the valve shaft rotates, which is generally widely spread, is used.

[0024] Briefly explaining with reference to Fig. 2, the water faucet 12 includes a cylindrical valve box 20. The upper half of the valve box 20 is covered by a dome-shaped splash prevention cover 22, and a plurality of water discharge ports 24 are formed on the upper part of the side wall of the valve box 20 so as to be arranged in the circumferential direction. Also, a bearing 26 having an internal thread formed on its inner peripheral surface is provided at the upper end of the valve box 20, and a valve shaft 28 having an external thread formed on its outer peripheral surface is screwed into this bearing 26 so as to penetrate the splash prevention cover 22. A disk-shaped valve body 30 having a water stop rubber 30a on its lower surface is provided at the lower end of this valve shaft 28. Also, a valve seat 32 having a water passage port 32a is provided at approximately the center inside the valve box 20. In such a water faucet 12, when a rotational force around the axis is applied to the valve shaft 28, the valve shaft 28 and the valve body 30 move up and down by a feed screw mechanism, and the water passage port 32a of the valve seat 32 is opened and closed. That is, the water faucet 12 of this embodiment includes a displacement mechanism including a valve body 30 that moves up and down as the valve shaft 28 rotates.

[0025] Returning to Fig. 1, such a water faucet 12 is arranged in a water supply basin 104 provided on the ridge 102, and is attached to the downstream end of a branch pipe 108 that branches from a water pipeline 106 laid under the ridge 102 and extends into the field 100. And an electric actuator 16 is attached above the water faucet 12, and the displacement mechanism (valve shaft 28 and valve body 30) of the water faucet 12 is operated by the electric actuator 16.

[0026] On the other hand, the drain outlet 14 is a drainage device for controlling the drainage from the field 100, and has a displacement mechanism including a partition body and the like. In this embodiment, a drain outlet 14 having a water level setting function is used. Briefly explaining, the drain outlet 14 includes a cylindrical partition body 34 whose upper end opening functions as a drain port, and by moving this partition body 34 up and down, it is possible to adjust the drain port to an arbitrary height.

[0027] Such a drain inlet 14 is disposed within a drain pan 110 provided on a ridge 102 and is attached to the upstream end of a drain pipe 114 that extends to a drain channel 112. An electric actuator 16 is attached to the drain inlet 14, and the displacement mechanism (partition body 34) of the drain inlet 14 is moved up and down by the electric actuator 16. However, when attaching the electric actuator 16 to the drain inlet 14, an adapter 36 that can convert the rotational force of the rotary shaft 66 of the electric actuator 16 into a force in the vertical direction (axial direction) and transmit it to the partition body 34 is used.

[0028] Referring to FIG. 3 together with FIG. 1, the electric actuator 16 is a device for operating the displacement mechanism of a water supply control device such as a water faucet 12 and a drain inlet 14 using the driving force of a motor 60, and includes an actuator main body 40 and a mounting portion 42 (mounting base) for attaching the actuator main body 40 to the water supply control device.

[0029] As shown in FIGS. 3 and 4, the actuator main body 40 includes a cylindrical main body case 50 formed of a synthetic resin such as rigid polyvinyl chloride. The main body case 50 constitutes the upper part of the housing of the electric actuator 16. Further, a plurality of first bolt holes 50a that are screwed with fixing bolts 80 are formed at predetermined intervals in the circumferential direction at the lower end of the main body case 50. In this embodiment, four first bolt holes 50a are formed at 90-degree intervals.

[0030] A solar cell panel 52 is detachably attached onto the main body case 50. The solar cell panel 52 is supported at a predetermined angle by a bent plate-shaped metal holding body 54.

[0031] Also, inside the main body case 50, an electronic substrate 56, a storage battery 58, and a drive mechanism including a motor 60 and a main gear 62 and the like are accommodated.

[0032] Although not shown in the figure, a control unit including a CPU, a memory, etc., and a wireless communication unit including a wireless communication module, etc. are disposed on the electronic substrate 56. A motor 60, an operation panel 68, a wireless communication unit, a sensor terminal, etc. are electrically connected to the control unit. The CPU of the control unit is in charge of overall control of the electric actuator 16 and controls the driving of the motor 60 and the like. The memory comprehensively represents a ROM, a RAM, an HDD, etc., stores a control program for controlling the operation of the electric actuator 16, and functions as a work area when the CPU operates. Further, the wireless communication unit is connected to an antenna and performs wireless communication with an external device such as a relay device via the antenna.

[0033] The storage battery 58 stores the electric power generated by the solar cell panel 52. The motor 60 is driven by the electric power stored in the storage battery 58. A small gear 64 is provided at the tip of the output shaft 60a of the motor 60, and the main gear 62 is connected to the small gear 64 and rotates around its axis receiving the driving force from the motor 60.

[0034] The main gear 62 is a two-boss type gear, and a substantially columnar rotating shaft 66 is inserted through the shaft portion of the main gear 62. A coupling portion 66a connected to the upper end portion of the valve shaft 28 of the water supply faucet 12 and the like is formed at the lower end portion of the rotating shaft 66. Further, a key groove 62a extending along the axial direction is formed on the inner peripheral surface of the shaft portion of the main gear 62, and a sliding key 66b fitted with the key groove 62a is formed on the outer peripheral surface of the rotating shaft 66 so as to extend along the axial direction. Thereby, the rotating shaft 66 rotates as the main gear 62 rotates and is slidable in the axial direction with respect to the shaft portion of the main gear 62.

[0035] On the outer surface of the main body case 50, an operation panel 68 for receiving operation instructions from the user, that is, for the user to directly operate the electric actuator 16, is provided. On the operation panel 68, a main power switch, an up button, a down button, and selection buttons for switching the operation mode (remote mode, automatic mode, manual mode, etc.) of the electric actuator 16 are appropriately provided. On this operation panel 68, connection terminals for connecting wiring extending from the sensor terminal are also provided.

[0036] As shown in FIG. 5, the attachment portion 42 constitutes the lower part of the housing of the electric actuator 16 and includes a cylindrical side wall portion 70 and a bottom plate portion 72 provided at the lower end of the side wall portion 70. The side wall portion 70 is formed of a synthetic resin such as rigid polyvinyl chloride, and the bottom plate portion 72 is formed of a metal such as aluminum and stainless steel.

[0037] An inspection port 70a (see FIG. 3) for performing maintenance management work such as operation confirmation and cleaning of the rotary shaft 66 and the like is formed in the side wall portion 70. Further, a plurality of holes 70b arranged at predetermined intervals in the circumferential direction are formed at the upper end of the side wall portion 70. In this embodiment, four holes 70b are formed at 90-degree intervals. By fastening the fixing bolt 80 through the hole 70b to the first bolt hole 50a of the main body case 50, the attachment portion 42 is fixed to the lower end portion of the main body case 50. On the other hand, a through hole 72a through which the upper end portion of the valve shaft 28 of the water supply faucet 12 and the like are inserted is formed at the central portion of the bottom plate portion 72. Further, a plurality of holes 72b arranged in the circumferential direction and the radial direction are formed around the through hole 72a in the bottom plate portion 72, and the attachment portion 42 (and thus the electric actuator 16) is bolted to the upper surface of the water supply faucet 12 and the like using these holes 72b.

[0038] As shown in FIG. 6, when attaching the electric actuator 16 onto the water faucet 12, with the electric actuator 16 placed on the splash prevention cover 22 of the water faucet 12, the splash prevention cover 22, the bearing 26, and the bottom plate portion 72 of the attachment portion 42 are bolted together. Also, the upper end portion of the valve shaft 28 of the water faucet 12 and the coupling portion 66a of the rotary shaft 66 of the electric actuator 16 are non-rotatably connected.

[0039] In the water faucet 12 with the electric actuator 16 attached, for example, when a user accesses the management server using a remote operation terminal and sends an operation instruction (control signal) such as to fully close, fully open, or set an arbitrary opening degree of the water faucet 12, a control signal corresponding to this operation instruction is transmitted from the management server to the electric actuator 16 via the relay machine. The control unit of the electric actuator 16 drives the motor 60 according to the received control signal. The driving force of this motor 60 is transmitted to the main gear 62, and the rotary shaft 66 rotates together with the main gear 62. Thereby, a rotational force is applied to the valve shaft 28 of the water faucet 12 fixedly connected to the rotary shaft 66. The valve shaft 28 to which the rotational force is applied is moved up and down by a screw mechanism, and the valve body 30 is moved to the fully open position, the fully closed position, etc.

[0040] Similarly, although not shown in the figure, when attaching the electric actuator 16 onto the drain outlet 14, the electric actuator 16 is placed on the pedestal provided on the drain outlet 14 and bolted, and the upper end portion of the connecting shaft of the adapter 36 is non-rotatably connected to the coupling portion 66a of the rotary shaft 66. In the drain outlet 14 with the electric actuator 16 attached, when the user sends an operation instruction for setting the drain outlet height (height position of the partition body 34) of the drain outlet 14, the control unit of the electric actuator 16 drives the motor 60 according to the control signal and changes the drain outlet height of the drain outlet 14.

[0041] As described above, in the water supply control device (water faucet 12 or drain 14) to which the electric actuator 16 is attached, during normal times, the displacement mechanism of the water supply control device is displaced (operated) electrically by the electric actuator 16. However, when a failure (malfunction) occurs in the electric actuator 16 or the like, it becomes necessary to displace the displacement mechanism of the water supply control device manually by manual operation. At this time, it takes time and effort to disconnect the connection between the valve shaft 28 of the water faucet 12 and the rotating shaft 66 of the electric actuator 16, or to attach a handle to the valve shaft 28 for manual operation.

[0042] Therefore, in this embodiment, the following configuration is adopted for the electric actuator 16 and the following manual operation method is adopted, so that the water supply control device can be easily manually operated. Hereinafter, it will be specifically described with reference to FIGS. 3 to 8.

[0043] As shown in FIGS. 3 to 8, in the electric actuator 16 of this embodiment, a structure is provided at the connecting portion between the actuator main body 40 and the mounting portion 42 that enables switching between a fixed state and a rotatable state of the actuator main body 40. That is, the actuator main body 40 is provided so as to be switchable between a fixed state in which it is fixed non-rotatably to the mounting portion 42 and a rotatable state in which it is rotatable in the circumferential direction with respect to the mounting portion 42.

[0044] As described above, a plurality of first bolt holes 50a are formed at predetermined intervals in the circumferential direction at the lower end portion of the main body case 50 of the actuator main body 40. On the other hand, a plurality of holes 70b are formed at predetermined intervals in the circumferential direction at the upper end portion of the side wall portion 70 of the mounting portion 42. Then, as can be clearly seen from FIG. 7, by screwing the fixing bolt 80 into the first bolt hole 50a through the hole 70b, the mounting portion 42 is fixed to the lower end portion of the main body case 50. That is, the actuator main body 40 is in a fixed state in which it is fixed non-rotatably to the mounting portion 42.

[0045] On the one hand, as shown in FIG. 8, by removing (releasing the screwing) the fixing bolt 80 from the first bolt hole 50a, the fixing of the mounting portion 42 to the main body case 50 is released. That is, the actuator main body 40 becomes in a rotatable state where it can rotate in the circumferential direction with respect to the mounting portion 42. In this embodiment, as the fixing bolt 80, a drop-preventing bolt having a thread 80a formed only at the tip portion is used. Thereby, when the screwing of the fixing bolt 80 to the first bolt hole 50a is released, the dropping of the fixing bolt 80 from the mounting portion 42 is prevented, and the loss of the fixing bolt 80 and the like are prevented.

[0046] Also, in this embodiment, the actuator main body 40 is provided rotatably in a state where it is prevented from coming off in the vertical direction with respect to the mounting portion 42 in the rotatable state. Specifically, an annular guide groove 70c extending in the circumferential direction is formed at a height position below the hole 70b on the inner surface of the upper end portion of the side wall portion 70 of the mounting portion 42. However, the height position of the guide groove 70c may be below or above the hole 70b as long as it is near the hole 70b. On the other hand, one or a plurality of second bolt holes 50b are formed at a height position corresponding to the guide groove 70c at the lower end portion of the main body case 50 of the actuator main body 40. For example, two second bolt holes 50b are formed at 180-degree intervals. A guide bolt 82 is attached to this second bolt hole 50b. At this time, the guide bolt 82 is provided such that the tip portion protrudes from the outer surface of the main body case 50, and the tip portion (protruding portion) of the guide bolt 82 is used as a guide protrusion 82a that engages with the guide groove 70c.

[0047] When rotating the actuator main body 40, the guide protrusion 82a fitted in the guide groove 70c moves along the guide groove 70c, so that the actuator main body 40 is rotated in a state where it is prevented from coming off in the vertical direction (the movement is restricted) with respect to the mounting portion 42. In this way, since the actuator main body 40 can rotate in a state where it is prevented from coming off in the vertical direction with respect to the mounting portion 42, the actuator main body 40 can be rotated smoothly and stably. Therefore, the water supply control device can be more easily manually operated.

[0048] Furthermore, a handle portion 86 (grip portion) that protrudes outward from the outer surface is provided at the upper end of the main body case 50. In this embodiment, the handle portion 86 is formed in an annular plate shape (flange shape) from a synthetic resin such as rigid polyvinyl chloride and is fixed to the outer surface of the main body case 50 by an appropriate method such as welding. However, the shape of the handle portion 86 can be changed as appropriate, and the handle portion 86 can also be formed in a rod shape or the like. By providing such a handle portion 86, it becomes easier for the operator to apply force and easier to rotate the actuator main body 40. Therefore, the water supply control device can be more easily manually operated.

[0049] Furthermore, in this embodiment, the circumferential position of the actuator main body 40 in the fixed state can be changed. As described above, in this embodiment, the first bolt holes 50a are formed at 90-degree intervals, so the actuator main body 40 can change the circumferential position (that is, the installation direction) with respect to the mounting portion 42 in four directions. By making it possible to change the circumferential position of the actuator main body 40 in the fixed state in this way, the orientation (installation direction) of the solar panel 52 can be adjusted to face south or the like. Note that by increasing the number of the first bolt holes 50a, it becomes possible to more finely adjust the circumferential position of the actuator main body 40 (and thus the orientation of the solar panel 52).

[0050] Next, a manual operation method of the water supply control device to which the electric actuator 16 as described above is attached will be briefly described. For example, in the water supply faucet 12 to which the electric actuator 16 is attached, when it becomes necessary to manually operate the water supply faucet 12, as shown in FIG. 8, the fixing bolt 80 is disengaged from the first bolt hole 50a to make the actuator body 40 rotatable. When a sensor terminal such as a water level sensor is connected to the electric actuator 16, the connector is removed. Then, without disconnecting the connection between the valve shaft 28 of the water supply faucet 12 and the rotating shaft 66 of the electric actuator 16 (that is, while the displacement mechanism of the water supply control device and the drive mechanism of the electric actuator 16 are connected), the handle portion 86 is gripped and the actuator body 40 is rotated in the circumferential direction (clockwise or counterclockwise). That is, while the attachment portion 42 is fixed to the water supply faucet 12, the entire actuator body 40 is rotated with respect to the attachment portion 42. When the actuator body 40 is rotated, the valve shaft 28 of the water supply faucet 12 also rotates together with the rotating shaft 66. Therefore, the valve shaft 28 to which the rotational force is applied is moved up and down by the screw mechanism, and the valve body 30 is moved to the fully open position, the fully closed position, etc. (that is, the displacement mechanism is displaced).

[0051] As described above, according to this embodiment, the actuator body 40 is provided so as to be switchable between a fixed state and a rotatable state with respect to the attachment portion 42. By rotating the actuator body 40 in the circumferential direction, the displacement mechanism of the water supply control device is displaced. Therefore, the water supply control device can be easily manually operated. That is, the water supply control device can be easily manually operated in an emergency or the like without disconnecting the connection between the displacement mechanism of the water supply control device and the drive mechanism of the electric actuator 16 and without providing a complicated mechanism such as a clutch structure in the electric actuator 16.

[0052] In the above-described embodiments, the electronic substrate 56, the storage battery 58, the motor 60, the main gear 62, etc. are accommodated inside the main body case 50, but the present invention is not limited thereto. For example, as in the embodiment shown in FIG. 9, only the drive mechanism such as the motor 60 and the main gear 62 is accommodated in the main body case 50, and the electronic substrate 56, the storage battery 58, etc. can also be arranged in another case provided outside the main body case 50. That is, the electric actuator 16 can be divided into a drive device including a drive mechanism and a control device including the electronic substrate 56 (control unit), and the actuator main body 40 attached to the water supply control device can be composed of only the drive device. In this case, the motor 60 may be electrically connected to the electronic substrate 56 via wiring 88 or the like.

[0053] As in the embodiment shown in FIG. 9, by accommodating only the drive mechanism such as the motor 60 and the main gear 62 in the main body case 50, that is, by configuring the actuator main body 40 attached to the water supply control device with only the drive device, the size and weight of the actuator main body 40 can be reduced. Therefore, it becomes easy to rotate the actuator main body 40 in the circumferential direction with respect to the attachment portion 42, and the water supply control device can be more easily manually operated in an emergency or the like.

[0054] In the above-described embodiments, the electric actuator 16 is provided with the solar cell panel 52. However, when a storage battery 58 with a large capacity is used, it is not always necessary to provide the solar cell panel 52. Further, when the field water management system 10 is applied to an environment where other power sources such as commercial power can be used, the electric actuator 16 does not necessarily need to be provided with the solar cell panel 52 and the storage battery 58.

[0055] Note that all of the specific numerical values such as the dimensions and the specific shapes mentioned above are merely examples, and can be appropriately changed according to the requirements such as the product specifications.

Explanation of Reference Numerals

[0056] 10... Field water management system 12... Water supply tap (water supply control device) 14 … Water inlet (water supply control device) 16 … Electric actuator 40 … Actuator body 42 … Mounting part 50 … Main body case 70c … Guide groove 80 … Fixing bolt 82 … Guide bolt 82a … Guide projection 86 … Handle part 100 … Field

Claims

1. An electric actuator that is attached to a water supply control device having a displacement mechanism for controlling water supply to or drainage from a field and operates the displacement mechanism, an actuator body having a drive mechanism for driving the displacement mechanism and a main body case for housing the drive mechanism, and a mounting portion for mounting the actuator body to the water supply control device, wherein the main body case has a first bolt hole formed at a lower end portion of the main body case, and has a second bolt hole formed at a lower end portion of the main body case at a height position different from the first bolt hole, wherein the mounting portion has a side wall portion fitted to a lower end portion of the main body case, a through hole formed in the side wall portion at a position corresponding to the first bolt hole, and has an annular guide groove formed in the side wall portion at a position corresponding to the second bolt hole and extending in the circumferential direction of the side wall portion, a fixing bolt screwed into the first bolt hole through the through hole, and a guide bolt screwed into the second bolt hole and having a tip engaged with the guide groove, the actuator body can be switched between a fixed state in which it is non-rotatably fixed to the mounting portion and a rotatable state in which it can rotate 360 degrees or more in the circumferential direction with respect to the mounting portion, and in the rotatable state, it can rotate in the circumferential direction with respect to the mounting portion in a state where it is prevented from coming off in the vertical direction with respect to the mounting portion by the guide bolt, in the rotatable state, the displacement mechanism can be displaced by rotating the actuator body in the circumferential direction while connecting the displacement mechanism and the drive mechanism. An electric actuator.

2. The electric actuator according to claim 1, wherein the fixing bolt is a drop-preventing bolt having a thread formed only at the tip portion.

3. The electric actuator according to claim 1 or 2, wherein the actuator body has an annular plate-shaped or rod-shaped handle portion protruding outward from an outer surface of the main body case.

Images