JP2019171981A - Refueling device of construction machine - Google Patents

Abstract

To provide a refueling device of a construction machine, which can achieve quick refueling by removing air tightness of a fuel tank, improve the convenience by eliminating the time and labor required to attach and detach a cap of a fuel filler opening and prevent the secondary damage caused by forgetting to attach the cap.SOLUTION: A fuel pump 19 is energized and operated by supplying electric power from a battery 23 in response to an ON operation of a fuel supply switch 24, to suck in the fuel stored in a drum can via a suction hose 20 and supply the fuel into a fuel tank 11. One end of an air vent line 26 is connected to the fuel tank 11 at a position above the liquid level when the fuel tank is full, and a normally-closed electromagnetic air vent valve 28 is connected to the other end of the air vent line 26. The fuel pump 19 and the air vent valve 28 are connected in parallel to the fuel supply switch 24, and a solenoid 28 of the air vent valve 28 is energized to open the valve in synchronization with the energization of the fuel pump 19 to open the inside of the fuel tank 11 to the atmosphere.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a fuel supply device for a construction machine.

  Unlike general passenger cars and trucks, this type of construction machine may be used in harsh environments such as dense forests and mountains. In such an area, a tank truck or the like for refueling cannot be easily provided, and therefore drums or the like storing fuel exclusively are used for refueling construction machines. Needless to say, the drum can does not have a fuel replenishment function. Therefore, a construction machine is equipped with a fuel replenishing device such as a hydraulic excavator described in Patent Document 1 so that fuel can be refilled by itself.

  In the hydraulic excavator of Patent Document 1, a fuel supply device is accommodated in a storage case installed on a frame of an upper swing body. The fuel pump of the fuel supply device is fixed in the storage case, and one end of the supply pipe is connected to the discharge port of the fuel pump. The supply pipe is drawn out of the storage case and the other end is connected to the fuel tank. Has been. Further, a suction hose is wound and accommodated in the storage case, one end of which is connected to the suction port of the fuel pump, and a strainer is fixed to the other end.

  When refueling, the suction hose is first pulled out of the storage case and the strainer is inserted into the drum can, and then the fuel refill switch is turned on. When the fuel pump is activated, the fuel in the drum can be supplied into the fuel tank via the suction hose, the fuel pump, and the supply pipe. When the fuel level reaches a predetermined liquid level, the fuel supply switch is turned off to supply the fuel. Complete.

JP 2002-266377 A

  By the way, engines installed in recent construction machines need to satisfy not only high power output and low fuel consumption but also exhaust gas regulations. For this reason, the fuel injection amount and injection timing of the engine are fine and highly accurate. It is controlled.

  On the other hand, even in a construction machine equipped with a fuel supply device, a fuel supply port is provided in the fuel tank and sealed with a removable cap, assuming fuel supply from a tank truck. This type of construction machine is used in construction sites where dust, sand, and the like (hereinafter collectively referred to as dust) are scattered. Therefore, if sealing with the cap is incomplete, dust that has entered from the fuel filler port will enter the fuel and the desired engine performance will not be achieved. Yes. As a result, if fuel is replenished with a fuel replenishment device with the cap attached, there will be no air escape in the airtight fuel tank, which obstructs fuel replenishment into the fuel tank and extremely reduces the replenishment speed. End up.

  Therefore, in general, when refueling by the fuel replenishing device, the cap is removed from the fuel filler port in order to release the airtightness of the fuel tank. However, it is very troublesome to climb a large construction machine every time you refuel and remove the cap, and if you forget to install the cap after refueling, dust or rain may enter the fuel tank. It will also be a cause of secondary damage.

  The present invention has been made to solve such problems, and the object of the present invention is to remove the airtightness of the fuel tank and realize quick fuel replenishment, and then to attach and detach the cap of the fuel filler port. An object of the present invention is to provide a refueling device for a construction machine that can improve the convenience by omitting the time and effort and prevent secondary damage caused by forgetting to attach the cap.

  In order to achieve the above object, a refueling device for a construction machine according to the present invention operates a fuel pump by supplying power from a battery, and refuels a construction machine that supplies fuel sucked through a suction hose to a fuel tank. In the apparatus, an air vent passage having one end connected to a position above the upper limit liquid level of the fuel tank, and provided in the air vent passage, and closes the air vent passage by closing when not energized, And an air venting means for opening the fuel tank to the atmosphere via the air vent line, which is opened by power supply from the battery in synchronization with the power supply to the fuel pump.

  According to the refueling device for a construction machine of the present invention, the airtightness of the fuel tank is released to realize quick fuel replenishment, and the convenience required for removing the cap of the fuel filler port can be reduced, and the convenience can be improved. Secondary damage caused by forgetting to attach the cap can be prevented.

It is a side view showing a hydraulic excavator equipped with a fuel supply device of an embodiment. It is a circuit diagram which shows the structure of a fuel supply apparatus.

Hereinafter, an embodiment in which the present invention is embodied in a fuel supply device for a hydraulic excavator will be described.
FIG. 1 is a side view showing a hydraulic excavator on which the fuel supply device of this embodiment is mounted. First, a schematic configuration of the hydraulic excavator will be described with reference to FIG.

  The lower traveling body 2 of the hydraulic excavator 1 is provided with a pair of left and right crawlers 3. The crawler 3 is driven by a traveling hydraulic motor (not shown) to cause the hydraulic excavator 1 to travel. An upper swing body 4 is provided on the lower traveling body 2, and the upper swing body 4 is driven to swing by a swing hydraulic motor (not shown). An articulated work front 5 is provided at the front part of the upper swing body 4, and the work front 5 includes a boom 6, an arm 7, and a bucket 8. The boom 6 is driven by the boom cylinder 6a, the arm 7 is driven by the arm cylinder 7a, and the bucket 8 is driven by the bucket cylinder 8a.

  A driver's cab 10 in which an operator is boarded is provided at the front part of the upper swing body 4 on the frame 9, and a fuel tank 11, a machine room 12, a counterweight 13, and the like are provided at the rear side of the driver's cab 10 on the frame 9. It has been. Although not shown, HST (Hydro Static Transmission) using an engine as a power source is mounted in the machine room 12, and the above-described traveling or turning hydraulic pressure is supplied by hydraulic oil supplied from a hydraulic pump driven by the engine. A motor and each cylinder 6a-8a operate | move.

  The fuel supply device 15 of this embodiment is installed adjacent to the right side of the fuel tank 11 as shown by a broken line in FIG. 1, and in the circuit diagram relating to fuel and electricity shown in FIG. The structure corresponding to is surrounded by a one-dot chain line.

  First, the fuel circuit will be described. A fuel supply port 11a is provided at the top of the fuel tank 11 and is sealed with a removable cap 16. For example, when refueling from a tank truck, the cap 16 is removed and the fuel is supplied. Fuel is supplied from the mouth 11a.

  One end of a supply pipe 18 in which a filter 17 is interposed is connected to one side of the fuel tank 11, and the other end of the supply pipe 18 is connected to a discharge port of a fuel pump 19. One end of a suction hose 20 is connected to the suction port of the fuel pump 19, and the length of the suction hose 20 is set so as to reach a drum can placed on the ground surface. The suction hose 20 is caught in a storage case (not shown) when the fuel supply device 15 is not used, and can be arbitrarily pulled out from the storage case when used.

  Next, the electric circuit will be described. The fuel pump 19 is connected to the in-vehicle battery 23 via the pump side wiring 22, and the fuel supply switch 24 is interposed in the pump side wiring 22. The fuel supply switch 24 is provided at a position where the hand can reach in a posture standing on the ground surface, and can be arbitrarily operated by an operator. When the fuel supply switch 24 is turned on, the fuel pump 19 is energized by the power supply from the battery 23 to operate.

  Although details will be described later, the fuel tank 19 is refueled by the operation of the fuel pump 19. Although not shown, the fuel replenishing device 15 has an automatic stop function, and the actual fuel level rises as the fuel is replenished to reach a preset full liquid level (upper limit liquid level). Then, the electric power flowing from the battery 23 to the fuel supply switch 24 is automatically cut off, and the fuel supply is ended. However, it is not always necessary to provide an automatic stop function, and an operator who performs fuel supply may visually check the fuel level and manually turn off the fuel supply switch 24.

The above configuration is common to, for example, the fuel replenishing device 15 of Patent Document 1, and the characteristic part of the present embodiment will be described next.
One end of an air vent line 26 (air vent path) is connected to the upper portion of the fuel tank 11, more specifically, above the liquid level when the fuel is full, and a filter 27 is interposed in the air vent line 26. At the other end, an electromagnetic air vent valve 28 (air venting means) is connected to the other end. Although not shown, the port of the air vent valve 28 is set downward to prevent dust from entering. The air vent valve 28 is configured as a normally closed type that is held closed when the solenoid 28a is not energized. When the air vent valve 28 is closed by the air vent valve 28, the air vent valve 28 is opened. The inside of the fuel tank 11 is opened to the atmosphere via the air vent line 26. The positional relationship between the filter 27 and the air vent valve 28 may be reversed.

  One end of a valve side wiring 29 is connected to the solenoid 28a of the air vent valve 28, and the other end of the valve side wiring 29 is connected to an intermediate point between the fuel pump 19 and the fuel supply switch 24 of the pump side wiring 22 described above. ing. As a result, the fuel pump 19 and the air vent valve 28 are connected to the fuel supply switch 24 in parallel. Therefore, when the fuel supply switch 24 is turned on and the electric power from the battery 23 is supplied to the fuel pump 19, the electric power is also supplied to the solenoid 28 a of the air vent valve 28.

Next, the operation when fuel is supplied from the drum can to the hydraulic excavator 1 by the fuel supply device 15 configured as described above will be described.
First, at a time other than refueling, the refueling switch 24 of the refueling device 15 is turned off, the power from the battery 23 is cut off, the fuel pump 19 stops without being energized, and the air vent valve 28 is closed. Thus, the air vent line 26 is closed. The fuel inlet 11a of the fuel tank 11 is sealed with a cap 16, and the inside of the fuel tank 11 is kept airtight without communicating with the outside. For this reason, the situation where dust enters the fuel tank 11 from the outside is avoided, and deterioration of the engine performance due to the fuel in which the dust is mixed is prevented.

  When the hydraulic excavator 1 is supplied with fuel, the suction hose 20 is pulled out from the storage case and the tip is inserted into the drum can, and then the fuel supply switch 24 is turned on. The fuel pump 19 is energized and operated by supplying power from the battery 23, and the fuel in the drum can be supplied into the fuel tank 11 through the suction hose 20, the fuel pump 19, and the supply line 18, and automatically stops when the tank is full. Refueling is terminated by the function.

  On the other hand, when the fuel supply switch 24 is turned on, the power from the battery 23 is also supplied to the solenoid 28 a of the air vent valve 28. Accordingly, the solenoid 28a of the air vent valve 28 is also energized in synchronization with the energization of the fuel pump 19, and the air vent valve 28 is opened. As a result, the inside of the fuel tank 11 is opened to the atmosphere via the air vent line 26 and the airtightness of the fuel tank 11 is released. As a result, the air in the fuel tank 11 is discharged to the outside through the air vent line 26 so as to be pushed out by the fuel supplied into the fuel tank 11. For this reason, fuel is smoothly supplied into the fuel tank 11 without being obstructed by air, and quick fuel replenishment can be realized.

  Further, at this time, the air in the air vent line 26 always flows from the fuel tank 11 side to the outside, but there is a possibility that the air will flow backward instantaneously for some reason. In this case, dust contained in the outside air enters the fuel tank 11 together with the outside air, but in this embodiment, the dust is captured by the filter 27 interposed in the air vent line 26. Therefore, it is possible to prevent dust from entering the fuel tank 11 due to such a backflow phenomenon of air.

  When the fuel supply is completed and the electric power from the battery 23 is cut off by the automatic stop function, the air vent valve 28 is closed simultaneously with the stop of the fuel pump 19. Therefore, the air vent line 26 is closed by the air vent valve 28, and the fuel tank 11 is returned to the airtight state again.

  As described above, the air tightness of the fuel tank 11 is released by opening the air vent valve 28 in conjunction with the operation of the fuel pump 19 (in other words, the start of fuel supply), and the fuel pump 19 is stopped (in other words, the fuel supply is replenished). The fuel tank 11 is returned to the airtight state by closing the air vent valve 28 in conjunction with the end of the air. Therefore, it is not necessary for an operator who refuels to climb the large excavator 1 every time the fuel is replenished, and to remove the cap 16 of the fuel filler port 11a, thereby greatly improving the convenience of refueling. Can do.

  Further, since the fuel tank 11 is automatically sealed and released by the interlocking operation of the air vent valve 28, there is a possibility that the cap 16 may be forgotten to be attached after refueling, as in the case where the cap 16 is manually removed. There is no. Therefore, secondary damage caused by this, for example, entry of dust, rain, etc. into the fuel tank 11 can be reliably prevented.

  This is the end of the description of the embodiment, but the aspect of the present invention is not limited to this embodiment. For example, in the above-described embodiment, the fuel replenishing device 15 of the hydraulic excavator 1 is embodied. However, the embodiment is not limited to this as long as it is intended for a construction machine, and may be applied to, for example, a wheel loader.

  In the above embodiment, the fuel filler 11a is provided in the upper part of the fuel tank 11, but the fuel filler 11a may be omitted when there is no opportunity to refuel from the tank truck. This is because the air in the fuel tank 11 at the time of refueling is released by the air vent valve 28, so that it is not necessary to remove the cap 16.

1 Hydraulic excavator (Construction machinery)
DESCRIPTION OF SYMBOLS 11 Fuel tank 15 Fuel supply apparatus 19 Fuel pump 20 Suction hose 23 Battery 24 Fuel supply switch 26 Air vent line (air vent path)
27 Filter 28 Air bleeding valve (Air bleeding means)
28a Solenoid

Claims (3)

In a refueling device for a construction machine that operates a fuel pump by supplying power from a battery and supplies fuel sucked through a suction hose to a fuel tank.
An air vent passage having one end connected to a position above the upper liquid level of the fuel tank;
The air vent passage is provided in the air vent passage to close the air vent passage when not energized, and closes the air vent passage by power supply from the battery in synchronism with power supply to the fuel pump. A refueling device for a construction machine, comprising: an air venting means for releasing the fuel tank to the atmosphere through a path. The air vent means is a normally closed air vent valve that is opened by energizing a solenoid;
The fuel pump and the air vent valve are respectively connected in parallel to a fuel supply switch connected to the battery, and the fuel is supplied by supplying power from the battery when the fuel supply switch is turned on. The refueling device for a construction machine according to claim 1, wherein a pump and a solenoid of the air vent valve operate in synchronization. The refueling device for a construction machine according to claim 1, wherein a filter is interposed in the air vent passage.

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