JPH0438136Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The invention includes a discharge passage that communicates a discharge port that opens at the bottom of a tank chamber with a discharge pipe, and a valve body that opens and closes the discharge port. This is related to the bottom valve of a tank truck.

(b) Problems to be solved by the prior art and the invention Conventionally, in tank trucks, the discharge ports of multiple tank chambers are connected to the same discharge piping. Because they are different, the discharge resistance is different, and if the bottom valves of each chamber are opened and discharged at the same time, each chamber will not finish discharging at the same time. Therefore, when discharging with a pump, it will be emptied first. Air is sucked in from the tank chamber, reducing pump performance and prolonging the pumping time.
In addition, the life of the pump may be shortened due to the pump idling. In addition, in aircraft refueling trucks, when the fuel in the tank chamber runs out and air is inhaled, the flow meter display does not match the amount of fuel loaded.
Moreover, there was a risk of pumping air into the aircraft's fuel tanks.

For this reason, a system was implemented in which a sensing device was installed at the bottom of the tank chamber to detect the liquid level, and when the liquid level dropped to a predetermined level, the bottom valve was closed based on a command from this sensing device. However, with this type of system, liquid remains at the bottom of the tank chamber, and installing the electrical wiring for the sensing device through the tank poses a risk of liquid leakage, which is not permitted by law, making it dangerous to run inside the tank. It was necessary to pass through and route the wiring further.

Furthermore, the mechanism for closing the bottom valve in response to a command from the sensing device is complicated, making it difficult to install it together with a manually operated valve.

(c) Means and effects for solving the problem The present invention provides a bottom valve that is equipped with a discharge passage that communicates the discharge port at the bottom of the tank with the discharge pipe and a valve body that opens and closes the discharge port. A cylinder device that opens the valve body against the force of the machine, and a manually operated valve that switches the pressurized air in the cylinder device between pressurization and release are provided, and a cylinder device is provided in the discharge passage to eliminate the internal liquid. This device is equipped with a sensing device that detects when the liquid has run out at a predetermined height in the discharge passage, and a solenoid valve that releases pressurized air in the cylinder device in response to a signal from this sensing device. When the sensor is activated, the bottom valve can be closed to prevent air from entering.

(d) Embodiment In the figure, reference numeral 1 indicates a tank truck, in which a tank 5 is mounted on a chassis frame 3. The tank 5 is divided into a plurality of tank chambers 9, 9, 9 by partition plates 7, 7, and a manhole 13 with an inlet 11 is provided at the top of the tank chamber 9, and an outlet 15 is opened at the bottom. However, it communicates with a discharge pipe 19 via a bottom valve 17. Discharge piping 1
9 communicates with the discharge port 25 via a switching valve 23 that communicates with the pump 21, and is configured to be switchable between power discharge by the pump 21, power loading, and gravity discharge. 27 is a driver's cab, and 29, 29 are wheels. The bottom valve 17 is constructed as follows. That is, 31 is the discharge port 15 and the discharge pipe 19
The valve body is provided with a discharge passage 33 therein, and is fixed to the bottom of the tank chamber 9 at an upper flange portion 35 with bolts 37. 39
is a valve body that can freely come into contact with a valve seat 41 provided at the upper end of the valve body 31, and a piston portion 43 provided at the upper part is fitted into a cylinder 45 fixed to the upper part of the valve body 31 so as to be able to move up and down. Reference numeral 47 denotes an opening provided at the bottom of the cylinder 45, which is covered with a wire mesh 49. The inner diameter of the cylinder 45 is approximately the same as the outer diameter of the valve body 39. Numeral 51 is a spring for pressing the valve body 39 in the closing direction, and 53 is a rod fixed to the lower end of the valve body 39, which passes through the lower surface of the valve body 31 vertically so as to be vertically movable. The chamber 55 above the piston portion 43 and the discharge passage 33 below the valve body 39 communicate with each other. 57 is the valve body 31
An arm 59 that engages with the lower end surface of the rod 53 is fixed to one end of the shaft, and an operating arm 61 is fixed to the other end.
Reference numeral 63 denotes a bullet that urges the arm 59 in a direction in which it comes into contact with the lower end surface of the rod 53. The operating arm 61 is connected via a rod 65 to a piston rod 69 of a cylinder device 67 by a coupling 71. The piston rod 69 is secured to a piston 77 which is slidably fitted at one end into a cylinder 75 which is pivotally connected to the frame 3 by a shaft 73. Cylinder device 6 provided for each bottom valve 17 of each chamber 9
7 is a compressor 7 for automobile brakes.
9. It is operated by the air in the air tank 8 via an electromagnetic operation valve 83 and a manual operation valve 85 arranged in series. A sensing device 89 is fixed to an opening 91 provided on the side of the valve body 31 facing the discharge passage 33. Light emitted from the control device 92 enters through an optical fiber 93, is reflected by a prism 95, and is detected by another sensor. Control device 92 via optical fiber 97
I look forward to going back. When the prism 95 is in the liquid, the density around the prism 95 is different, so the reflection direction is different and no light flows into the optical fiber 97. The control device 92 is configured as follows. That is, input electricity passes through a constant voltage circuit 99 and a pulse circuit 101 to the light emitting diode 1.
03 to emit light and send the light to the sensing device via the optical fiber 93. The light returned from the optical fiber 97 is converted into a current by a photodiode 105, and outputted through an arithmetic circuit 107 and an amplifier circuit 109.
It is configured to be sent to the solenoid 111 of the electromagnetically operated valve 83.

In the above embodiment, when unloading the liquid in the tank chambers 9, 9, 9, the manual operation valve 85 of each bottom valve 17 is switched from the position a to the position b in FIG. The air in 81 enters each cylinder device 67, presses piston 77, and rotates operating arm 61 in the direction of arrow A. Therefore, the arm 59 pushes up the lower end of the rod 53, and the valve body 39 rises against the bullet 51, causing the bottom valve 17 to rise.
is opened, and the liquid in each tank chamber 9 is discharged from the discharge pipe 1.
9, the switching valve 23, the pump 21, and the discharge port 25 through a discharge hose (not shown) to be discharged into an underground tank or the like. Next, the power to the sensing device 89 is turned on. At the end of the discharge, for example, if the liquid in the first tank chamber 9 is discharged first, the liquid in the discharge passage 33 of the bottom valve 17 disappears, and the liquid around the prism 95 of the sensing device 89 disappears, causing air to flow out. When exposed inside, the reflection angle changes, and the light from the optical fiber 93 is reflected by the prism 95 and flows to the optical fiber 97, where it is amplified by the control device 92 and then the electromagnetic operated valve 83.
The air flows to the solenoid 111, which switches the electromagnetic operation valve 83 from the c position to the d position in FIG. Since the pressing air pressure is released, the valve body 39 is closed by the elastic force of the bullet 51, and the arm 61 returns together with the piston 77 in the direction opposite to the arrow A in FIG. Therefore, the air in the first tank chamber 9 is not sucked into the discharge pipe 19. When all the liquid in the tank chamber 9 is thus discharged, each manually operated valve 85 is returned to position a. The solenoid operated valve 83 returns to position c when the power is cut off using a switch (not shown). The power supply to the control device 92 of the sensing device 89 is turned on after the liquid has entered the discharge passage 33.

(e) Effects of the invention The invention has the following effects. (1) When discharging the liquid in all tank chambers at the same time using a pump, this prevents air from being sucked in from the tank chamber that has been drained first, reducing the performance of the pump and prolonging the draining time. (2) Prevent errors in flowmeters caused by pressurizing air into aircraft fuel tanks. (3) The liquid inside the tank can be completely drained. (4) Since the sensing device is installed outside the tank, the wiring can be easily shortened. (5) By arranging the manually operated valve and the electromagnetic operated valve in series, it becomes possible to open and close the pneumatic bottom valve manually and close it using a signal from the sensing device. (6) By using a pneumatic bottom valve, it can be applied to large open/close valves such as tank truck bottom valves.

[Brief explanation of the drawing]

Fig. 1 is a side view of a tank truck equipped with a bottom valve according to the present invention, Figs. 2 and 3 are a front sectional view and a side view of an embodiment of the present invention, respectively, and Fig. 4 is a main part of the pressurized air. FIG. 5 is an explanatory diagram of the electrical circuit of the sensing device. 9...tank chamber, 15...discharge port, 17...bottom valve, 19...discharge piping, 33...discharge passage, 39
... Valve body, 51 ... Bullet machine, 67 ... Cylinder device, 83 ... Solenoid operated valve, 85 ... Manually operated valve,
89...Sensing device.

Claims (1)

[Scope of utility model registration request] A bottom valve 17 is provided, which includes a discharge passage 33 that communicates the discharge port 15 that opens at the bottom of the tank chamber 9 with the discharge pipe 19, and a valve body 39 that opens and closes the discharge port 15. A cylinder device 67 that opens the valve body 39 against the engine 51 and a manually operated valve 85 that switches the pressurized air in the cylinder device 67 between pressurization and release are provided. It is characterized by being provided with a sensing device 89 that is provided to sense that the internal liquid has run out, and an electromagnetic operated valve 83 that releases pressurized air in the cylinder device 67 in response to a signal from the sensing device 89. Bottom valve device for tank trucks.