JPS5931329Y2 - Automatic stop device for pump drive motor of fluid sprayer - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an automatic stopping device for a pump drive motor of a fluid sprayer for agricultural use.

In fluid dispersion machines such as power sprayers that are towed by tractors, etc., because they are towed behind the tractor, even if the chemical tank is empty and the pump is idling, it is not noticed, and the pump may seize due to overheating.・There was a risk of wear and tear.

Therefore, there is a need for a device that automatically stops the pump drive motor when the drug in the tank runs out.

Conventionally, this type of device has a floating switch built into the tank that automatically shuts off the motor circuit in response to a drop in the liquid level, but this tends to cause malfunctions due to disturbances in the liquid level due to vibrations, etc.

The present invention has been devised in view of the above-mentioned problems, and it is an object of the present invention to provide an automatic stop device for a pump drive motor of a fluid sprayer that has a simple structure and operates reliably.

Therefore, its characteristic feature is that in a fluid sprayer in which a motor-driven pump is installed in the middle of a flow pipe that communicates a tank and a sprayer, a drop in fluid pressure inside the flow pipe on the discharge side of the pump is detected. In addition, an electric switch is provided whose switch contact is released by actuation of the member, and the switch is incorporated in series with an electric circuit for driving a motor.

Embodiments of the present invention will be described in detail below with reference to the drawings.

In Figure 1, 1 is a tank, 2 is a dispersion device at the end,
3 is a flow tube.

The flow pipe 3 communicates the tank 1 and the spraying device 2, and a motor-driven pump 4 is interposed in the middle thereof.

The illustrated example shows a pump 4 directly connected to a motor 5.

The pump 4 has a suction port 6 and a discharge lower part, and the respective ports 6,
7 is connected to the flow tube 3.

FIG. 2 shows details of the discharge lower.

In FIG. 2, a cylindrical body 9 which is open at both ends and has female threads and male threads cut on the outer periphery of both ends is screwed onto the inner periphery of a boss 8 provided on the side wall of the pump 4.

A radial communication hole 10 is provided at approximately the center of the cylinder 9 in the longitudinal direction, and a swivel joint 11 is fitted therein.

An annular groove 12 is provided on the inner circumference of the swivel joint 11 and communicates with the communication hole 10 .

An outlet hole 13 communicating with this annular groove 12 is provided in the radial direction of the swivel joint 11, and a discharge side flow pipe 3a is connected to the outlet hole 13.

A diaphragm 14 is provided to cover the outer end opening of the cylindrical body 9, and the diaphragm 14 is held in a pinched manner by a cap 15 which is screwed onto a male thread of the cylindrical body 9.

A push rod 16 is inserted through the cap 15 and is movable in the axial direction in conjunction with the movement of the diaphragm 14 .

The outer end of the push rod 16 is in contact with an actuating part 18 of an electric switch 17.

In the illustrated example, a limit switch is adopted as the electric switch 1γ, and a bracket 19 fixed to the cap 15 is used as the electric switch 1γ.
installed on.

This electric switch 17 is electrically wired as shown in FIG.

That is, 20 is a batch ', 1-121 is a starting push button switch, and 22 is an 0NOFF switch, which are connected in series to the motor 5 in the above order, and are further wired from the motor 5 back to the battery 20.

The electric switch 17 is connected between the battery 20 and the push button switch 21 and between the push button switch 21 and the changeover switch 22, and is arranged in parallel with the push button switch 21.

To explain the operation of the above embodiment of the present invention, first, 0N
-Turn the OFF switch 22 ON.

Next, press the starting push button switch 21 to turn it on.
The battery 20 and the motor 5 are directly connected, and the motor 5 rotates.

Thereby, the pump 4 is driven, and the agricultural chemicals in the tank 1 flow through the flow tube 3 and are sprayed from the spray device 2 at the end.

At this time, the liquid pressure in the discharge side flow pipe 3a of the pump 4 has been increased to the discharge pressure of the pump 4, so the diaphragm 14 provided on the discharge lower, that is, the member for detecting fluid pressure, is pushed outward. do.

This pressure causes the diaphragm 14 to bulge outward and push the push rod 16, which in turn causes the electric switch 17 to operate in conjunction with the push rod 16.
The actuating portion 18 of is pushed and the electric switch 1T is turned on.

In this state, let go of the starting push button switch 21 and turn off the push button switch 21.

However, the power from the battery 20 is
Since the motor 5 is supplied to the motor 5 through the circuit on the 7 side, the motor 5 is continuously operated.

When the drug in the tank 1 is emptied, the diaphragm 14 detects a drop in fluid pressure and returns to its original state, and in conjunction with this, the switch contact of the electric switch 17 is released, contrary to the above, and the The circuit of switch 17 is turned off.

As a result, the power to the motor 5 is cut off, and the motor 5 is stopped.

In the above embodiment of the present invention, the diaphragm 14 is used as a member for detecting a decrease in fluid pressure, but the present invention is not limited to this, and for example, a piston or the like operated by fluid pressure may be used.

Further, although a limit switch is used as the electric switch 17, it is not limited to this.

The present invention is provided with a member that detects a drop in fluid pressure inside the discharge side flow pipe 3a of the pump 4, and an electric switch 17 whose switch contact is released when the member is activated, and the switch 17 is used to drive the motor 5. Since it is integrated in series with the electric circuit, the structure is simple and the motor 5 can be stopped reliably, and there are no malfunctions like those using conventional floating switches, so it has great practical effects. It is something that demonstrates the.

[Brief explanation of the drawing]

FIG. 1 is a piping/wiring diagram showing an embodiment of the present invention, and FIG. 2 is an enlarged sectional view showing section A in FIG. 1. 1... Tank, 2... Spraying device, 3.
...Flow pipe, 3a...Discharge side flow pipe, 4...
...Pump, 5...Motor, 14...
...Diaphragm (detection member), 17...Electric switch.

Claims (1)

[Scope of utility model registration request] In a fluid sprayer in which a motor-driven pump is interposed in the middle of a flow pipe that communicates a tank and a sprayer, a member is provided to detect a drop in fluid pressure inside the flow pipe on the discharge side of the pump, and 1. An automatic stop device for a pump-driving motor of a fluid sprayer, characterized in that an electric switch whose switch contact is released when actuated is installed in series with an electric circuit for driving a motor.