JP7710083B2 - Electric Actuator - Google Patents

Description

This invention relates to an electric actuator, and in particular to an electric actuator that is attached to a water supply control device that has a displacement mechanism for controlling the supply of water to or drainage from a field, and that operates the displacement mechanism.

One example of a water supply control device equipped with a conventional electric actuator is disclosed in Patent Document 1. With the technology of Patent Document 1, by attaching an electric actuator that drives a water supply control device such as a water faucet or a water outlet, it is possible to manage water in a field by remote operation or automatic control. 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.

Another example of a conventional electric actuator is disclosed in Patent Document 2. The electric actuator in Patent Document 2 is an electric valve actuator that is attached to the input side of a reducer that drives a part-turn valve, and drives the reducer by slowing down the rotation of the motor using a worm and a worm wheel. In this electric actuator, a drive sleeve is provided inside the worm wheel, and an output shaft that connects to the reducer is provided inside the drive sleeve. In addition, one end of a clutch is provided on the drive sleeve or the output shaft, and a manual handle is provided on the other end of the clutch. The clutch is disengaged when the motor is started, and is engaged when the motor is stopped, making it possible to open and close the valve simply by rotating the manual handle when the motor is stopped.

JP 2020-103099 A JP 2016-160969 A

In the event of a breakdown in the electric actuator, it may become necessary to manually displace (open or close) the displacement mechanism of the water supply control device. With the technology of Patent Document 1, when manually operating the water supply control device, it is necessary to disconnect the valve shaft (or connecting shaft) of the water supply control device from the rotating shaft of the electric actuator, and then attach a handle to the valve shaft and turn it, which makes manual operation time-consuming.

On the other hand, the technology in Patent Document 2 requires a clutch mechanism to disconnect the motor shaft and a mechanism to transmit the rotation of the manual handle to the rotating shaft of the electric actuator, which makes the structure of the electric actuator complex. As the structure becomes more complex, the electric actuator becomes larger and more expensive.

Therefore, the primary object of this invention is to provide a novel electric actuator.

Another object of the invention is to provide an electric actuator that allows the water supply control device to be easily operated manually in an emergency, etc.

A first invention is an electric actuator attached to a water supply control device equipped with a displacement mechanism for controlling water supply to or drainage from a field, and actuating the displacement mechanism, the actuator comprising: an actuator body having a drive mechanism for driving the displacement mechanism and a main body case for accommodating the drive mechanism; and an attachment portion for attaching the actuator body to the water supply control device, the main body case having a first bolt hole formed in a lower end portion of the main body case and a second bolt hole formed in the lower end portion of the main body case at a height position different from that of the first bolt hole, the attachment portion having a side wall portion fitted with 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 a side bolt hole formed in the side wall portion at a position corresponding to the second bolt hole. an actuator body that is fixed to the mounting portion so as not to rotate and a rotatable state that is rotatable 360 degrees or more in a circumferential direction relative to the mounting portion; and a guide bolt that is screwed into the second bolt hole and has a tip engaged with the guide groove. The actuator body is switchable between a fixed state in which it is fixed non-rotatably to the mounting portion and a rotatable state in which it can rotate circumferentially relative to the mounting portion by the guide bolt. In a state in which it is prevented from coming loose in the vertical direction relative to the mounting portion by the guide bolt, the actuator body can rotate in the circumferential direction relative to the mounting portion in the rotatable state. In the rotatable state, the actuator body can be rotated in the circumferential direction while the displacement mechanism and the drive mechanism are connected, and the displacement mechanism can be displaced by rotating the actuator body in the circumferential direction.

According to the first invention, by simply placing the actuator body in a rotatable state, the displacement mechanism of the water supply control device can be displaced by rotating the actuator body in a circumferential direction 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 the electric actuator with a complex mechanism such as a clutch structure. Therefore, the water supply control device can be easily manually operated in an emergency. Furthermore, since the actuator body can be rotated smoothly and stably, the water supply control device can be manually operated even more easily.

The second invention is based on the first invention, and the fixing bolt is a fall-proof bolt with a thread formed only on the tip portion.

The third invention is dependent on the first or second invention, and the actuator body has a ring-shaped or rod-shaped handle portion that protrudes outward from the outer surface of the body case.

According to the third invention, the actuator body can be easily rotated by gripping the handle portion, making it easier to manually operate the water supply control device.

According to this invention, the water supply control device can be easily operated manually in an emergency without disconnecting the displacement mechanism of the water supply control device from the drive mechanism of the electric actuator, and without providing the electric actuator with a complex mechanism such as a clutch structure.

The above and other objects, features and advantages of the present invention will become more apparent from the detailed description of the embodiments given below with reference to the drawings.

1 is a diagram showing a field water management system using an electric actuator according to an embodiment of the present invention; FIG. 2 is a diagram showing the internal structure of a water faucet. FIG. 2 is a diagram illustrating an internal structure of the electric actuator. FIG. 2 is a diagram showing an actuator main body. FIG. FIG. 1 is a diagram showing a water faucet equipped with an electric actuator. 13 is an enlarged schematic view showing a connection portion between the actuator body and a mounting portion in a fixed state; FIG. 13 is an enlarged schematic view showing a connecting portion between the actuator body and a mounting portion in a rotatable state; FIG. FIG. 11 is a schematic diagram showing an electric actuator according to another embodiment of the present invention;

Referring to FIG. 1, an electric actuator 16 according to an embodiment of the present invention is attached to a water supply control device such as a water tap 12 and a water outlet 14 installed in a farm field 100, and operates a displacement mechanism of the water supply control device. As will be described in detail later, the electric actuator 16 comprises an actuator body 40 and an attachment portion 42 provided on its lower side, and the connection portion between the actuator body 40 and the attachment portion 42 has a structure that can be switched between a fixed state and a rotatable state.

In this embodiment, the electric actuator 16 is used in the field water management system 10. Below, we will first briefly explain an example of the configuration of the field water management system 10. However, the configuration of the field water management system 10 (such as the specific configurations of the water supply tap 12, the water outlet 14, and the electric actuator 16) is not limited to this and can be changed as appropriate.

As shown in FIG. 1, the field water management system 10 is a field facility that manages water in a field 100 by remote control or automatic control based on a pre-stored program. In this embodiment, the field water management system 10 includes a water supply tap 12 and a water outlet 14, and an electric actuator 16 is attached to each of the water supply tap 12 and the water outlet 14. In other words, electric actuators 16 having the same structure are used as the electric actuators that drive the displacement mechanisms of the water supply tap 12 and the water outlet 14.

Although not shown in the figure, the field 100 is appropriately equipped with sensor terminals such as a water level sensor, such as an ultrasonic sensor that detects the field water level, various temperature sensors that detect air and water temperatures, a pressure sensor that detects air pressure, and a soil moisture sensor that detects soil moisture. The sensor terminals are connected to the electric actuator 16 via wiring.

In this embodiment, the field water management system 10 is a system including a plurality of cultivated areas divided by ridges 102. The water taps 12 and the water outlets 14 are installed in each cultivated area, and the electric actuators 16 attached to them are wirelessly connected to a repeater (parent unit) by a wireless communication method according to a specific low-power wireless standard (920 MHz band). Each electric actuator 16 is then wirelessly connected to a remote control terminal such as a smartphone, tablet terminal, PDA, or PC owned by the user via the repeater and a management server or the like installed on the network. However, the electric actuators 16 may also wirelessly communicate with external devices such as the management server or remote control terminal without going through the repeater.

It is advisable to use cloud computing for this wireless communication. For example, information acquired by each electric actuator 16 (information on the status 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 outlet height of the water outlet 14, and sensor information such as the field water level received from the sensor terminal) is sent to a cloud server, which is an example of a management server, as needed and stored. A user can access the cloud server from a remote control terminal to check the information acquired by each electric actuator 16 and remotely control each electric actuator 16 using the remote control terminal to manage the water in the field 100.

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 the type that is widely used and in which the valve shaft and valve body move up and down as the valve shaft rotates is used.

Briefly described with reference to FIG. 2, the water supply valve 12 has a cylindrical valve box 20. The upper half of the valve box 20 is covered by a dome-shaped splash-proof cover 22, and a plurality of water outlets 24 are formed in a circumferential arrangement on the upper side wall of the valve box 20. A bearing 26 having a female thread on the inner circumferential surface is provided at the upper end of the valve box 20, and a valve shaft 28 having a male thread on the outer circumferential surface is screwed into this bearing 26 so as to penetrate the splash-proof cover 22. A disk-shaped valve body 30 having a water stop rubber 30a on the lower surface is provided at the lower end of the valve shaft 28. A valve seat 32 having a water passage port 32a is provided in the approximate center of the valve box 20. In such a water supply valve 12, when a rotational force about the axis is applied to the valve shaft 28, the valve shaft 28 and the valve body 30 move up and down by the feed screw mechanism, and the water passage port 32a of the valve seat 32 is opened and closed. That is, the water supply valve 12 in this embodiment is equipped with a displacement mechanism that includes a valve body 30 that moves up and down as the valve shaft 28 rotates.

Returning to FIG. 1, such a water supply tap 12 is placed 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 off from an irrigation pipeline 106 laid under the ridge 102 and extends into the field 100. An electric actuator 16 is attached above the water supply tap 12, and the displacement mechanism (valve shaft 28 and valve body 30) of the water supply tap 12 is operated by the electric actuator 16.

On the other hand, the water outlet 14 is a drainage device for controlling drainage from the field 100, and has a displacement mechanism including a partition. In this embodiment, a water outlet 14 with a water level setting function is used. Simply put, the water outlet 14 has a cylindrical partition 34 whose upper opening functions as a drainage outlet, and the drainage outlet can be adjusted to any height by moving this partition 34 up and down.

Such a water outlet 14 is placed in a drainage basin 110 provided on the ridge 102, and is attached to the upstream end of a drainage pipe 114 that extends to the drainage channel 112. An electric actuator 16 is attached to the water outlet 14, and the displacement mechanism (partition body 34) of the water outlet 14 is moved up and down by the electric actuator 16. However, when attaching the electric actuator 16 to the water outlet 14, an adapter 36 is used that can convert the rotational force of the rotating shaft 66 of the electric actuator 16 into a force in the up and down direction (axial direction) and transmit it to the partition body 34.

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

As shown in Figures 3 and 4, the actuator body 40 includes a cylindrical body case 50 made of synthetic resin such as rigid polyvinyl chloride. The body case 50 constitutes the upper part of the housing of the electric actuator 16. In addition, a plurality of first bolt holes 50a that screw into the fixing bolts 80 are formed at a predetermined interval in the circumferential direction at the lower end of the body case 50. In this embodiment, four first bolt holes 50a are formed at 90 degree intervals.

A solar panel 52 is removably attached to the top of the main body case 50. The solar panel 52 is supported at a predetermined angle by a bent plate-shaped metal holder 54.

The main body case 50 also contains an electronic board 56, a storage battery 58, and a drive mechanism including a motor 60 and a main gear 62.

Although not shown, the electronic board 56 is provided with a control unit including a CPU and memory, and a wireless communication unit including a wireless communication module. The motor 60, operation panel 68, wireless communication unit, sensor terminal, and the like are electrically connected to the control unit. The CPU of the control unit is responsible for the overall control of the electric actuator 16, and controls the driving of the motor 60, etc. The memory is a comprehensive reference to ROM, RAM, HDD, etc., and stores a control program that controls the operation of the electric actuator 16 and functions as a work area when the CPU is operating. The wireless communication unit is also connected to an antenna, and performs wireless communication with external devices such as a repeater via the antenna.

The storage battery 58 stores the electricity generated by the solar panel 52. The motor 60 is driven by the electricity 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, so that it receives driving force from the motor 60 and rotates around its axis.

The main gear 62 is a double-boss type gear, and a roughly cylindrical rotating shaft 66 is inserted into the shaft portion of the main gear 62. A coupling portion 66a is formed at the lower end of the rotating shaft 66, which is connected to the upper end of the valve shaft 28 of the water supply faucet 12, etc. Also, 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 that fits into the key groove 62a is formed on the outer peripheral surface of the rotating shaft 66 so as to extend along the axial direction. As a result, the rotating shaft 66 rotates as the main gear 62 rotates, and is able to slide axially relative to the shaft portion of the main gear 62.

An operation panel 68 is provided on the outer surface of the main body case 50 to receive operation instructions from the user, i.e., to allow the user to directly operate the electric actuator 16. The operation panel 68 is appropriately provided with a main power switch, an up button, a down button, and a selection button for switching the operation mode of the electric actuator 16 (remote mode, automatic mode, manual mode, etc.). This operation panel 68 is also provided with connection terminals for connecting wiring extending from the sensor terminal.

As shown in FIG. 5, the mounting 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, for example, from a synthetic resin such as rigid polyvinyl chloride, and the bottom plate portion 72 is formed from a metal such as aluminum or stainless steel.

The side wall portion 70 is formed with an inspection port 70a (see FIG. 3) for checking the operation of the rotating shaft 66 and for performing maintenance work such as cleaning. In addition, a plurality of holes 70b are formed at the upper end of the side wall portion 70 at a predetermined interval in the circumferential direction. In this embodiment, four holes 70b are formed at 90 degree intervals. The mounting portion 42 is fixed to the lower end of the main body case 50 by fastening a fixing bolt 80 to the first bolt hole 50a of the main body case 50 through this hole 70b. Meanwhile, a through hole 72a is formed in the center of the bottom plate portion 72, through which the upper end of the valve shaft 28 of the water supply faucet 12 and the like are inserted. In addition, a plurality of holes 72b are formed in the bottom plate portion 72 in the circumferential and radial directions around the through hole 72a, and the mounting portion 42 (and thus the electric actuator 16) is bolted to the upper surface of the water supply faucet 12 and the like using this hole 72b.

As shown in FIG. 6, when mounting the electric actuator 16 on the water faucet 12, the electric actuator 16 is placed on the splash prevention cover 22 of the water faucet 12, and the splash prevention cover 22 and the bearing 26 are bolted to the bottom plate portion 72 of the mounting portion 42. In addition, the upper end of the valve shaft 28 of the water faucet 12 and the coupling portion 66a of the rotating shaft 66 of the electric actuator 16 are non-rotatably connected.

In the case of a water faucet 12 to which an electric actuator 16 is attached, for example, when a user accesses a management server using a remote control terminal and transmits an operation instruction (control signal) to fully close, fully open, or open the water faucet 12 to an arbitrary degree, a control signal corresponding to the operation instruction is transmitted from the management server to the electric actuator 16 via a repeater. The control unit of the electric actuator 16 drives the motor 60 in response to the received control signal. The driving force of the motor 60 is transmitted to the main gear 62, and the rotating shaft 66 rotates together with the main gear 62. As a result, a rotational force is applied to the valve shaft 28 of the water faucet 12, which is fixedly connected to the rotating shaft 66. 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 a fully open position, a fully closed position, or the like.

Similarly, although not shown, when mounting the electric actuator 16 on the water outlet 14, the electric actuator 16 is placed on a base provided on the water outlet 14 and bolted, and the upper end of the connecting shaft of the adapter 36 is non-rotatably connected to the coupling part 66a of the rotating shaft 66. When the user transmits an operation command to set the drain height of the water outlet 14 (height position of the partition body 34) in the water outlet 14 to which the electric actuator 16 is attached, the control part of the electric actuator 16 drives the motor 60 in response to the control signal to change the drain height of the water outlet 14.

As described above, in a water supply control device (water supply tap 12 or water outlet 14) to which an electric actuator 16 is attached, the displacement mechanism of the water supply control device is normally electrically displaced (operated) by the electric actuator 16. However, when a failure (malfunction) occurs in the electric actuator 16, it becomes necessary to manually displace the displacement mechanism of the water supply control device. In such cases, it is time-consuming to disconnect the valve shaft 28 of the water supply tap 12 from the rotating shaft 66 of the electric actuator 16 or to attach a handle to the valve shaft 28 to perform manual operation.

In this embodiment, the following configuration is adopted for the electric actuator 16, and the following manual operation method is adopted to allow the water supply control device to be easily operated manually. A detailed explanation is given below with reference to Figures 3 to 8.

As shown in Figures 3 to 8, in the electric actuator 16 of this embodiment, a structure is provided at the connection portion between the actuator body 40 and the mounting portion 42 that allows the actuator body 40 to be switched between a fixed state and a rotatable state. In other words, the actuator body 40 is provided so as to be switchable between a fixed state in which it is fixed to the mounting portion 42 so as not to rotate, and a rotatable state in which it is rotatable in the circumferential direction relative to the mounting portion 42.

As described above, a plurality of first bolt holes 50a are formed at a predetermined interval in the circumferential direction at the lower end of the main body case 50 of the actuator main body 40. Meanwhile, a plurality of holes 70b are formed at a predetermined interval in the circumferential direction at the upper end of the side wall portion 70 of the mounting portion 42. Then, as can be clearly seen from FIG. 7, the mounting portion 42 is fixed to the lower end of the main body case 50 by screwing the fixing bolt 80 into the first bolt hole 50a through the hole 70b. In other words, the actuator main body 40 is fixed to the mounting portion 42 in a fixed state so that it cannot rotate.

On the other hand, as shown in FIG. 8, by removing (unscrewing) the fixing bolt 80 from the first bolt hole 50a, the attachment portion 42 is released from the main body case 50. In other words, the actuator body 40 is placed in a rotatable state in which it can rotate circumferentially relative to the attachment portion 42. In this embodiment, a fall-prevention bolt with a thread 80a formed only at the tip is used as the fixing bolt 80. This prevents the fixing bolt 80 from falling off the attachment portion 42 when the fixing bolt 80 is unscrewed from the first bolt hole 50a, and prevents the fixing bolt 80 from being lost.

In this embodiment, the actuator body 40 is rotatably mounted in a rotatable state in a state where it is prevented from coming off in the vertical direction relative to the mounting portion 42. Specifically, an annular guide groove 70c extending in the circumferential direction is formed on the inner surface of the upper end of the side wall portion 70 of the mounting portion 42 at a height position lower than the hole 70b. However, the height position of the guide groove 70c may be below or above the hole 70b as long as it is close to the hole 70b. On the other hand, one or more second bolt holes 50b are formed at the lower end of the main body case 50 of the actuator body 40 at a height position corresponding to the guide groove 70c. 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 so that its tip protrudes from the outer surface of the main body case 50, and the tip (protruding portion) of the guide bolt 82 is used as a guide protrusion 82a that engages with the guide groove 70c.

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

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 a circular plate shape (brim shape) from synthetic resin such as hard 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 into a rod shape, etc. By providing such a handle portion 86, it becomes easier for the operator to apply force and rotate the actuator main body 40. Therefore, the water supply control device can be manually operated more easily.

Furthermore, in this embodiment, the circumferential position of the actuator 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 circumferential position of the actuator body 40 relative to the mounting portion 42 (i.e., the installation direction) can be changed in four directions. In this way, by making the circumferential position of the actuator body 40 in the fixed state changeable, the orientation (installation direction) of the solar cell panel 52 can be adjusted to face south, for example. Note that by increasing the number of first bolt holes 50a, it becomes possible to adjust the circumferential position of the actuator body 40 (and thus the orientation of the solar cell panel 52) more finely.

Next, a manual operation method of the water supply control device to which the electric actuator 16 is attached as described above will be briefly described. For example, when it becomes necessary to manually operate the water supply faucet 12 to which the electric actuator 16 is attached, as shown in FIG. 8, the fixing bolt 80 is released from the first bolt hole 50a to make the actuator body 40 rotatable. If a sensor terminal such as a water level sensor is connected to the electric actuator 16, the connector is removed. Then, without disconnecting the valve shaft 28 of the water supply faucet 12 from the rotating shaft 66 of the electric actuator 16 (i.e., 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). In other words, the entire actuator body 40 is rotated relative to the mounting portion 42 while the mounting portion 42 is fixed to the water supply faucet 12. When the actuator body 40 is rotated, the valve shaft 28 of the water supply valve 12 also rotates together with the rotating shaft 66, and the valve shaft 28 to which a rotational force is applied is moved up and down by the screw mechanism, and the valve body 30 is moved to a fully open position, a fully closed position, etc. (i.e., the displacement mechanism is displaced).

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 relative to the mounting portion 42, and the displacement mechanism of the water supply control device is displaced by rotating the actuator body 40 in the circumferential direction, so that the water supply control device can be easily operated manually. In other words, the water supply control device can be easily operated manually in an emergency, etc., without releasing 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 complex mechanism such as a clutch structure in the electric actuator 16.

In the above embodiment, the electronic board 56, the storage battery 58, the motor 60, the main gear 62, etc. are housed inside the main body case 50, but this is not limited to this. For example, as shown in the embodiment in FIG. 9, only the drive mechanism such as the motor 60 and the main gear 62 can be housed inside the main body case 50, and the electronic board 56 and the storage battery 58 can be placed in another case provided outside the main body case 50. In other words, the electric actuator 16 can be divided into a drive unit including a drive mechanism and a control unit including the electronic board 56 (control unit), and the actuator main body 40 attached to the water supply control device can be composed of only the drive unit. In this case, the motor 60 can be electrically connected to the electronic board 56 via wiring 88, etc.

As shown in the embodiment in FIG. 9, by accommodating only the drive mechanism such as the motor 60 and main gear 62 within the main body case 50, i.e., by configuring the actuator body 40 attached to the water supply control device with only the drive device, it is possible to reduce the size and weight of the actuator body 40. This makes it easier to rotate the actuator body 40 in the circumferential direction relative to the mounting part 42, and makes it easier to manually operate the water supply control device in an emergency, etc.

In the above embodiment, the electric actuator 16 is provided with a solar panel 52, but if a large-capacity storage battery 58 is used, it is not necessary to provide the solar panel 52. In addition, if the field water management system 10 is applied to an environment where other power sources, such as a commercial power source, can be used, the electric actuator 16 is not necessarily required to provide the solar panel 52 and storage battery 58.

Note that the specific values and shapes of the dimensions given above are merely examples and can be changed as necessary depending on the product specifications, etc.

10 ... Field water management system 12 ... Water supply valve (water supply control device)
14 ... Water outlet (water supply control device)
16 electric actuator 40 actuator body 42 mounting portion 50 body case 70c guide groove 80 fixing bolt 82 guide bolt 82a guide projection 86 handle portion 100 field

Claims (3)

An electric actuator attached to a water supply control device having a displacement mechanism for controlling water supply to or drainage from a farm field, the electric actuator actuating the displacement mechanism,
an actuator body having a drive mechanism that drives the displacement mechanism and a body case that houses the drive mechanism; and an attachment portion for attaching the actuator body to the water supply control device,
The main body case includes:
a first bolt hole formed in a lower end of the main body case; and a second bolt hole formed in the lower end of the main body case at a height position different from that of the first bolt hole,
The mounting portion is
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 an annular guide groove formed in the side wall portion at a position corresponding to the second bolt hole and extending in a circumferential direction of the side wall portion,
a fixing bolt that is screwed into the first bolt hole through the through hole, and a guide bolt that is screwed into the second bolt hole and has a tip portion engaged with the guide groove,
the actuator body is switchable between a fixed state in which it is fixed non-rotatably to the mounting portion and a rotatable state in which it is rotatable 360 degrees or more in a circumferential direction relative to the mounting portion, and in a state in which it is prevented from coming off the mounting portion in the up and down directions by the guide bolt, it is rotatable in the circumferential direction relative to the mounting portion in the rotatable state,
In the rotatable state, the actuator body is rotated in a circumferential direction while the displacement mechanism and the drive mechanism are connected to each other, thereby displacing the displacement mechanism . The electric actuator according to claim 1, wherein the fixing bolt is a fall-proof bolt with a thread formed only at the tip. The electric actuator according to claim 1 or 2, wherein the actuator body has a ring-shaped or rod-shaped handle portion that protrudes outward from the outer surface of the body case.