JPH0311492Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to an electric speed reduction mechanism, and more specifically, to a small-sized valve drive actuator.

(Prior Art) Electric power is generally used to open and close valves (including intermediate stops between fully open and fully closed), and manual operation is required during maintenance or in emergencies such as power outages. For this reason, this type of actuator has (a): from electric operation to manual operation, (b):
A switching mechanism from manual operation to electric operation is required.

Conventionally, this switching mechanism was built into the worm wheel section or the motor section (first stage reduction section). Also, a spring return type switching mechanism has often been adopted.

(Problems to be solved by the invention) However, this conventional device has the following problems.

1. When built into the worm wheel, the final reduction ratio becomes large, so a large torque is applied during electric operation, which requires a large switching operation force, and also requires large parts.

2. When built into the motor section (first stage reduction section) Each sequence component is built into this section for actuator control, and it is unreasonable in terms of space. Even if it could be installed, the manual handle would have to be rotated many times before the main shaft could be rotated.

3. Spring return types are often used for both the switching lever and manual handle necessary for the switching mechanism from electric operation to manual operation, but it is necessary to hold down the switching lever when operating the manual handle, resulting in a two-handed operation.

(Means for Solving the Problems) The present invention has been made to solve the problems of the conventional art.The switching operation force is small, and the rotation speed of the manual handle does not increase until the main shaft is rotated. In addition, to provide a valve drive actuator that has a built-in automatic return mechanism that requires only small parts and eliminates the need to constantly press the switching lever during manual operation by automatically returning the switch by rotation on the electric motor side. It is in.

The gist is that a bevel gear that is electrically driven via a spur gear reduction part and a manual handle are rotatably supported on a common shaft, and that one bevel gear slides on the common shaft between the bevel gear and the manual handle. Alternatively, a clutch plate is provided that connects with the other manual handle to drive the common shaft, and the clutch plate is biased to one side with a spring and constantly connected to the bevel gear, and the clutch plate connected to the bevel gear is pushed to the other side to operate the manual handle. A switching lever is provided that is connected to the handle, and an automatic return cam that is pressed upright against the side of the bevel gear by a spring is pivoted to the clutch plate pressing part of the switching lever, and a worm reduction part that is connected to the opening/closing shaft of the valve is installed. A valve drive actuator having a built-in automatic return mechanism characterized in that an input shaft is slidably connected to a common shaft.

(Function) In the present invention, the clutch is slid by a switching lever and connected to either a bevel gear driven by a motor or a manual handle, and the driving force of either one is transmitted to the next stage worm reduction section. There is.

Torque transmission during electric operation is as follows: motor -> spur gear reduction part -> bevel gear part -> clutch plate -> common shaft -> worm -> worm wheel -> main shaft.

Torque transmission during manual operation is manual handle → clutch plate → common shaft → worm → worm wheel →
Becomes the main axis.

The automatic return cam operates as follows. That is, during manual operation, the clutch plate is slid and connected to the manual handle by the switching lever. At this time, the cam stands upright against the side of the bevel gear and presses against it. That is, the cam uses the side surface of the bevel gear as support to press the clutch plate pressing portion of the switching lever, and maintains this state. When the motor operates and the bevel gear rotates, the cam rotates from the support shaft in the direction of rotation of the bevel gear, so the clutch plate pressing part loses support and the clutch plate is slid in the direction of the bevel gear by the biasing force of the spring and connected. At the same time, the switching lever is also returned to the electric side.

(Example) Examples of the present invention will be described below based on the drawings.

The actuator 1 of this embodiment performs three-step deceleration by a spur gear reduction section 3 connected to the electric motor 2, a bevel gear reduction section 4 connected to the spur gear reduction section 3, and a worm gear reduction section 5.

In the figure, 6 is a clutch plate, 7 is a manual handle, 8 is a common shaft, 9 is a spline, 10 is a bevel gear side meshing tooth, 11 is a manual handle side meshing tooth, 12 is a switching lever, 13 is a pressing part, 14 is a clutch spring It is.

Furthermore, when the switching lever 12 is in the manual position 16, the automatic return cam 15 connects the contact point 17 between the pressing part 13 and the clutch plate 6, the support shaft 18 of the cam 15, and the bevel gear side surface 19 and the tip of the cam 15. The contact points 20 of are arranged in a straight line.

In the figure, 21 indicates that the cam 15 is always connected to the bevel gear side 19.
a cam spring biased in the direction of standing upright, 22;
2 is a gripping portion of the manual handle 7, 23 is a worm, and 2
4 is a worm wheel, 25 is a torque detection mechanism, 2
6 is the main axis.

(Effects of the invention) As explained above, according to the invention, the manual handle is pivotally supported at the next stage of the spur gear reduction unit connected to the electric motor to drive the final stage worm gear reduction unit. The operating force required for switching is small, the number of rotations of the manual handle does not increase until the main shaft is rotated, and each part is small, making it economical. Furthermore, since the cam is pressed against the bevel gear rotated by the electric motor, the cam rotates with the rotation of the bevel gear, switching the clutch to the electric side and automatically returning the switching lever.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the embodiment of the present invention during manual operation, FIG. 2 is an explanatory diagram showing the main parts during automatic return, and FIG. 3 is an explanatory diagram showing the main parts returned to the electric side, FIG. 4 is an explanatory diagram of the cam portion. 1: Actuator, 2: Electric motor, 3: Spur gear reduction section, 4: Bevel gear reduction section, 5: Worm gear reduction section, 6: Clutch plate, 7: Manual handle, 8: Common shaft, 9: Spline, 10: Bevel gear Side meshing teeth, 11: Manual handle side meshing teeth, 1
2: Switching lever, 13: Pressing part, 14: Clutch spring, 15: Cam, 18: Support shaft, 19: Side surface of bevel gear, 21: Cam spring, 26: Main force shaft.

Claims (1)

[Scope of utility model registration request] A bevel gear and a manual handle that are electrically driven via a spur gear reduction part are rotatably supported on a common shaft, and the bevel gear and the manual handle slide on the common shaft, and one bevel gear or the other manual handle is rotatably supported. A clutch plate is provided that is connected to the handle and drives a common shaft, and the clutch plate is biased to one side by a spring to constantly connect with the bevel gear, and the clutch plate connected to the bevel gear is pressed to the other side to connect with the manual handle. A switching lever is provided, and an automatic return cam that presses upright against the side of the bevel gear with a spring is pivotally supported on the clutch plate pressing part of the switching lever.
A valve drive actuator with a built-in automatic return mechanism, characterized in that the input shaft of the worm reduction unit, which is connected to the opening/closing shaft of the valve, is slidably connected to a common shaft.