JPS5813323Y2 - Water discharge pressure detection device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a water discharge pressure detection device for setting and detecting water discharge pressure mainly in fire pumps.

In general, pressure detection devices employ a method of sensing pressure by replacing pressure and movement with a proportional relationship using a pressure receiving part such as a diaphragm or bellows and a spring force.

When using this method, the pressure setting range (0 to 2
0 yen 1) is wide, and in order to sense with high accuracy even at any pressure, it is necessary to increase the operation per unit pressure.

Therefore, this idea has a pressure receiving part with short movement.

In order to increase the operation per unit pressure, the spring force of the spring can be varied, and detection can be performed with simultaneous precision even at any set pressure in the high-pressure to low-pressure housing.

Further, the variable spring force allows the detection pressure to be freely selected and the discharge pressure to be set arbitrarily.

Furthermore, the switch is turned on to switch from automatic operation to manual operation when the lowest discharge pressure is reached during automatic operation, which prevents unexpected discharge pressure from being applied to the nozzle. This is something that can be prevented.

Next, an embodiment of this invention will be described with reference to the drawings.

In FIG. 1, a cross section of a water discharge pressure detection device S for setting and detecting pressure is shown, and the connecting cylinder 1 of this detection device S is as follows:
It is fixed to the case 4a of the detection device.

One end thereof is connected to a conduit 2 through which the discharge side of the water pump passes, and the other end is connected to a pressure receiving part 3 such as a bellows described below.

The pressure receiving part 3 is connected to the connecting cylinder 1 at its end side, and discharge pressure is applied from inside the pressure receiving part, and the pressure receiving part 3 is expanded and contracted, converting the pressure into a change in position in the axial direction.

A core 16 made of a magnetic material 5 and a non-magnetic material γ is connected to the other end of the pressure receiving portion 3, and the pressure is transmitted to the position changing core 16.

The magnetic material 5 is inserted into the detection coil 6 and connected to the non-magnetic material γ approximately at the center of the detection coil 6, and the connection point is located approximately at the center of the detection coil 6 when the pressure and the spring 10 are balanced. ing.

The detection coil 6 outputs a change in inductance due to the movement of the magnetic body 5 from a terminal 6a, and is applied to the arithmetic circuit 20 in FIG. 2.

A spring receiver 8 is attached to the other end of the non-magnetic material T, and a spring 10 is elastically supported between the spring receiver 8 and a spring receiver 9 described below.

The handle 11 has a shaft 12 rotatably attached to the spring case 4.
This shaft 12 is provided with a threaded portion 12a in which a thread is carved inside the spring case 4b, and the spring receiver 9 is screwed into this threaded portion 12a.

Therefore, by rotating the handle 11, the spring receiver 9
can be moved left and right in the drawing to change the spring force of the spring 10.

In this embodiment, the switch 13 is a microswitch, which is fixed to the spring case 4b, and a rod 15 fixed to the spring receiver 9 contacts the roller 14 of the switch.
Open this switch 13.

The spring force of the spring 10 has become smaller, that is,
It is detected that the spring receiver 9 is positioned to the leftmost position.

Therefore, by rotating the handle 11, the spring receiver 9 is moved.
When the spring force of the spring 10 increases, the rod 15 is released from contact with the roller 14 of the switch 13, and the switch 13 is closed.

In the above configuration, when the water pump is driven, its discharge pressure is sent from the inside of the connecting cylinder 1 to the pressure receiving part 3 such as a bellows, and this pressure is converted into a positional change and is opposed to the spring 10.
When the pressure and the spring 10 are balanced, the connection point between the magnetic body 5 and the non-magnetic body 7 is located approximately at the center of the detection coil 6.

If the discharge pressure rises or falls for some reason, spring 1
The balance with the spring 10 is lost, and the magnetic body 5 is moved to the right or left in the figure by a position shift that is balanced with the spring 10.

Therefore, the detection coil 6. The inductance is changed by the movement of the magnetic body, and an increase or decrease in pressure is detected.

The detection coil 6 is one element of the detection circuit, and constitutes an oscillation circuit consisting of the detection coil 6 and a capacitor, for example, so the oscillation frequency and amplitude change, and this output is sent to the arithmetic circuit 20 shown in FIG. Rectifying and smoothing the DC voltage within the controller, inputting the DC voltage to the electronic governor 21, moving the control rack of the injection pump 22 in accordance with the change, and changing the rotation speed of the engine 25 by changing the injection amount of the injection pump, The water discharge pressure of the water pump 23 is automatically adjusted.

Dimensions.

To set the pressure, turn the handle 11 to change the setting force of the spring 10, and the magnetic body 5 will move.

As a result, the inductance of the detection coil 6 changes, the governor is controlled accordingly, the rotational speed of the engine changes due to the change in the injection amount, and the discharge pressure of the water pump 23 changes.

The change in discharge pressure occurs when the connection point of the magnetic body 5 is located approximately at the center of the detection coil 5! The movement is stopped when it is balanced with the spring 10.

Then, the same set pressure control 75 as described above is performed dynamically.

In this way, the set pressure can be set freely, and the spring force of the spring 10 is changed every time the set pressure is set, so that detection can be performed with the same accuracy.

To switch from automatic pressure adjustment operation to manual pressure adjustment operation of this device, rotate the handle 11 of the detection device S,
When the spring force of the spring 10 is made the smallest, the spring receiver 9 is moved to the right in the figure to the maximum, the rod 15 comes into contact with the roller 14 of the switch 13, and the switch 13 is opened.

Therefore, the detection device S is turned off and a control signal is sent from the manual rotation speed setting accelerator 24 to the arithmetic circuit 20, thereby switching from automatic operation to manual operation.

In other words, during automatic operation, the device switches to manual operation when the discharge pressure (water discharge pressure) becomes the lowest.
When switching from manual operation to automatic operation, the spring force of the spring 10 is the smallest, which can prevent sudden water discharge pressure from being sent to the nozzle, and can prevent dangers such as firefighters falling down. .

In this way, this invention has a pressure receiving part with short movement in the detection device and a spring that can vary the spring force opposing it, so it can detect with the same accuracy even at any set pressure from high pressure to low pressure. It is something that can be done.

Furthermore, the variable spring force allows the detection pressure to be freely selected and the water discharge pressure to be set arbitrarily.

Furthermore, since the configuration allows switching between automatic operation and manual operation when the spring force is at its lowest, sudden water discharge pressure is prevented from being sent during the initial stage of automatic operation, reducing the risk of firefighters falling. It is something that can be prevented.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a water discharge pressure detection device for setting and detecting pressure according to this invention, and FIG. 2 is a block diagram of this invention. 3...Pressure receiving part, 5...Magnetic material, 6...
...Detection coil, 9...Spring holder, 10...
・・・Ba&11・・・・・・No1ndol, 12
-・-Rod, 13...Switch,...
・Rod, S... Water discharge pressure detection device. 5

Claims (1)

[Scope of utility model registration request] Water discharge pressure is guided to a pressure receiving part 3 such as a bellows, and this pressure is converted into a positional change in the pressure receiving part 3, and the pressure receiving part 3 is connected to a magnetic material 5 and a non-magnetic material γ inserted in a detection coil 6. A handle 11 is provided to face the spring 10 through a core 16, and detect the position of the magnetic body 5 from the detection coil 6, and can arbitrarily change the spring force of the spring 10. When the spring force of the spring 10 is at its minimum, the rod 15 fixed to the spring receiver 9 screwed onto the rod 12 rotated by the switch 13 contacts the switch 13 to switch from automatic pressure adjustment to manual pressure adjustment. A water discharge pressure detection device characterized by: