JP6769782B2 - Excavator - Google Patents

Description

The present invention relates to excavators.

Excavators equipped with an exhaust gas treatment device for purifying the exhaust gas of a diesel engine as a power source and a storage tank for storing a treatment agent (for example, a liquid reducing agent such as an aqueous urea solution) used in the exhaust gas treatment device are known. (See, for example, Patent Document 1 and the like).

JP-A-2010-236208

The storage tank for storing the treatment agent is usually provided with an air bleeding pipe that communicates between the inside and the outside (outside air) in order to cope with fluctuations in the internal air pressure (inside pressure).

However, if the end of the air bleeding pipe inside the storage tank is submerged under the liquid level of the treatment agent, for example, the internal pressure due to the unused treatment agent being returned from the exhaust gas treatment device to the storage tank when the excavator is keyed off. The treatment agent may leak out of the storage tank through the air vent pipe as the amount rises.

Therefore, in view of the above problems, it is an object of the present invention to provide an excavator capable of suppressing leakage of the treatment agent to the outside of the storage tank through the air vent pipe.

In order to achieve the above object, in one embodiment,
A storage tank that stores the treatment agent that purifies the exhaust gas of the engine with the opening closed by the filler cap ,
Provided so as to be inserted into the interior of the storage tank to replenish the processing agent, a filler Ru with the filler cap to the end,
When the treatment agent is replenished from the opening with the filler cap removed, air provided in the filler so that only the inside of the filler and the inside of the storage tank communicate with the atmosphere. With a drawing pipe,
Excavators are provided.

According to the above-described embodiment, it is possible to provide an excavator capable of suppressing leakage of the treatment agent to the outside of the storage tank through the air vent pipe.

It is a side view which shows an example of an excavator. It is a top view which shows typically the upper swing body of an excavator. It is a block diagram which shows typically an example of the structure of the exhaust gas treatment apparatus. It is a right side view near the mounting position of the urea water tank in the upper swivel body. It is a perspective view which shows an example of the structure of the urea water tank. It is sectional drawing which shows an example of the structure of the urea water tank. It is sectional drawing which shows an example of the structure of the filler in a urea water tank.

Hereinafter, modes for carrying out the invention will be described with reference to the drawings.

In the description in all the attached drawings, the same or corresponding members or parts are designated by the same or corresponding reference numerals, and duplicate description will be omitted. Further, the drawings are not intended to show relative ratios between members or parts unless otherwise specified. Therefore, specific dimensions can be determined by those skilled in the art in light of the following non-limiting embodiments. Further, the embodiments described below are not limited to the invention, but are exemplary, and all the features and combinations thereof described in the embodiments are not necessarily essential to the invention.

First, the basic configuration of the excavator according to the present embodiment will be described with reference to FIGS. 1 and 2. Hereinafter, the extending direction of the boom 4 (see FIGS. 1 and 2) (direction indicated by arrow X1 in FIG. 2) is "front", and the opposite direction (direction indicated by arrow X2 in FIG. 2) is "rear". I will proceed with the explanation on the premise that.

FIG. 1 is a side view showing an example of an excavator according to the present embodiment.

In the excavator according to the present embodiment, the upper swivel body 2 is rotatably mounted on the upper part of the lower traveling body 1, and the cab 3 is provided on one side (for example, the left side) of the front part of the upper swivel body 2. Further, the boom 4 is pivotally attached to the center of the front portion of the upper swing body 2 so as to be able to be raised and lowered, and the arm 5 is connected to the tip portion of the boom 4 so as to be vertically rotatable. Further, a bucket 6 is attached to the tip of the arm 5 so as to be vertically rotatable.

FIG. 2 is a plan view schematically showing the upper swivel body 2.

As shown in FIG. 2, an engine room 7 is provided at the rear of the upper swing body 2.

A diesel engine 8 is installed in the engine room 7. The diesel engine 8 is arranged so that its rotation axis is aligned substantially in the left-right direction.

A cooling fan 11 driven by the power of the diesel engine 8 is disposed at the left end of the diesel engine 8 in the engine room 7, and heat exchange including a radiator and the like is provided on the left side of the cooling fan 11. The vessel unit 13 is arranged.

Further, in the engine room 7, an exhaust pipe 9 for discharging exhaust gas to the atmosphere is connected to the diesel engine 8. Further, an exhaust gas treatment device 10 for purifying the exhaust gas of the diesel engine 8 is mounted on the downstream side of the exhaust pipe 9.

The exhaust gas treatment device 10 includes, for example, a selective reduction type NOx treatment device that uses a liquid reducing agent as a treatment agent for purifying NOx in the exhaust gas. The exhaust gas treatment device 10 injects a liquid reducing agent (for example, an aqueous urea solution) upstream of the selective reduction catalyst 67 (see FIG. 3) provided in the exhaust pipe 9 to reduce NOx in the exhaust gas, and at the same time, The reduction reaction is promoted by a reduction catalyst to detoxify NOx. Hereinafter, the description will proceed on the premise that the liquid reducing agent is an aqueous urea solution (hereinafter, simply referred to as “urea water”).

As shown in FIG. 2, the upper swirl body 2 is equipped with a urea water tank 20 (an example of a storage tank) for storing urea water. In this example, the urea water tank 20 is arranged on the opposite side of the cab 3, that is, on the right front side with the boom 4 of the upper swing body 2 interposed therebetween. A tool box 21 is adjacently arranged in front of the urea water tank 20. A fuel tank 19 is arranged adjacent to the urea water tank 20.

Next, the configuration of the exhaust gas treatment device 10 will be described with reference to FIG.

FIG. 3 is a configuration diagram schematically showing an example of the configuration of the exhaust gas treatment device 10. As described above, the exhaust gas treatment device 10 purifies the exhaust gas discharged from the diesel engine 8 through the exhaust pipe 9.

The operation of the diesel engine 8 is controlled by an engine control module (hereinafter referred to as "ECM") 60.

The exhaust gas discharged from the diesel engine 8 through the exhaust manifold (not shown) passes through the turbocharger 61, reaches the exhaust pipe 9 downstream of the turbocharger 61, is purified by the exhaust gas treatment device 10, and then is in the atmosphere. Is discharged to.

On the other hand, the intake air introduced into the intake pipe 64 through the air cleaner 63 passes through the turbocharger 61, the intercooler 65, etc., and is supplied to the diesel engine 8.

The exhaust gas treatment device 10 includes a diesel particulate filter (DPF: Diesel Particulate Filter) 66, a selective reduction catalyst 67, a urea water injection valve 68, and the like.

The DPF 66 collects particulate matter in the exhaust gas. The DPF 66 is arranged on the exhaust pipe 9 on the upstream side of the selective reduction catalyst 67.

The selective reduction catalyst 67 continuously reduces and removes NOx in the exhaust gas by receiving the supply of the liquid reducing agent. In the present embodiment, urea water is used as the liquid reducing agent as described above because of its ease of handling. The selective reduction catalyst 67 is arranged on the exhaust pipe 9 on the downstream side of the DPF 66.

The urea water injection valve 68 is arranged in the downstream portion of the DPF 66 and the upstream portion of the selective reduction catalyst 67 in the exhaust pipe 9 (that is, the exhaust pipe 9a connecting the DPF 66 and the selective reduction catalyst 67). The urea water injection valve 68 is connected to the urea water tank 20 via the urea water supply line 69.

A urea water supply pump 70 is arranged in the urea water supply line 69.

Further, a strainer 71 having a built-in filter is arranged at one end of the urea water tank 20 of the urea water supply line 69. The filter in the strainer 71 captures (adsorbs) dust contained in the urea water.

The position of the filter may be arbitrary as long as it is on the urea water supply line 69. For example, the filter is arranged in a portion outside the urea water tank 20 in the urea water supply line 69. You may.

The urea water stored in the urea water tank 20 is supplied to the urea water injection valve 68 by the urea water supply pump 70, and is supplied from the urea water injection valve 68 to the upstream side of the selective reduction catalyst 67 in the exhaust pipe 9 (that is, the exhaust pipe). It is injected into 9a).

The urea water injected from the urea water injection valve 68 is thermally decomposed and hydrolyzed in the exhaust pipe 9 (exhaust pipe 9a) before reaching the selective reduction catalyst 67 to generate ammonia. As a result, the generated ammonia reduces NOx contained in the exhaust gas in the selective reduction catalyst 67, and the exhaust gas is purified.

Further, the exhaust gas treatment device 10 is provided with NOx sensors 72 and 73.

The NOx sensor 72 is arranged on the upstream side (that is, the exhaust pipe 9a) of the urea water injection valve 68 in the exhaust pipe 9. That is, the NOx sensor 72 detects the NOx concentration in the exhaust gas before the NOx reduction treatment by the selective reduction catalyst 67.

The NOx sensor 73 is arranged at the downstream end of the selective reduction catalyst 67. That is, the NOx sensor 73 detects the NOx concentration in the exhaust gas after the NOx reduction treatment by the selective reduction catalyst 67.

Further, the urea water tank 20 is provided with a urea water remaining amount sensor 74. The urea water remaining amount sensor 74 detects the urea water remaining amount in the urea water tank 20.

Further, the NOx sensors 72 and 73, the urea water remaining amount sensor 74, the urea water injection valve 68, and the urea water supply pump 70 are communicably connected to the urea water system controller 75. The urea water system controller 75 controls the injection amount of urea water injected from the urea water injection valve 68 to the exhaust pipe 9 (9a) based on the NOx concentration detected by the NOx sensor 72. Specifically, the urea water system controller 75 determines an appropriate amount of urea water to be injected from the urea water injection valve 68 into the exhaust pipe 9a based on the NOx concentration detected by the NOx sensor 72. Then, the urea water system controller 75 controls the operation of the urea water injection valve 68 and the urea water supply pump 70 so that an appropriate amount of urea water is injected into the exhaust pipe 9a.

Further, the urea water system controller 75 is based on the urea water remaining amount output from the urea water remaining amount sensor 74 via the urea water remaining amount sensor controller 74a, and the ratio of the urea water remaining amount to the total volume of the urea water tank 20. (Hereinafter, referred to as "urea water remaining amount ratio") is calculated. For example, a urea water remaining amount ratio of 50% indicates that half of the capacity of the urea water tank 20 remains in the urea water tank 20.

The urea water remaining amount sensor controller 74a is communicably connected to the urea water system controller 75 via a predetermined communication means such as CAN (Controller Area Network). Further, the urea water system controller 75 is communicably connected to the ECM 60 that controls the diesel engine 8 via a predetermined communication means such as CAN or the like. Further, the ECM 60 is connected to the excavator controller 76 by a predetermined communication means such as CAN. That is, various information about the exhaust gas treatment device 10 included in the urea water system controller 75 can be shared with the excavator controller 76 that controls the drive of the excavator.

The ECM60, the urea water remaining amount sensor controller 74a, the urea water system controller 75, and the excavator controller 76 may each be configured around a microcomputer including a CPU, a RAM, a ROM, an input / output port, and the like.

Further, a monitor 77 is communicably connected to the excavator controller 76. The monitor 77 is mounted at a position visible to the operator seated in the cockpit in the cab 3. For example, various warnings, excavator operating conditions, and the like are displayed on the monitor 77.

Further, the exhaust gas treatment device 10 has an antifreezing mechanism for preventing the urea water tank 20 and the urea water supply line 69 from freezing. In this example, the antifreeze mechanism uses cooling water (hereinafter, referred to as “engine cooling water”) for cooling the diesel engine 8 passing through the pipe 80. Specifically, the engine cooling water immediately after cooling the diesel engine 8 passes through the first portion 80a of the pipe 80 and reaches the second portion 80b while maintaining a relatively high temperature. The second portion 80b, which is a part of the pipe 80, may be in contact with the outer surface of the urea water tank 20, or may pass through the inside of the urea water tank 20, for example. When the engine cooling water flows through the second portion 80b, it supplies heat to the urea water in the urea water tank 20 through the outer surface of the urea water tank 20 or directly. After that, the engine cooling water supplies heat to the urea water supply line 69 and the urea water inside the urea water supply line 69 as it flows through the third portion 80c of the pipe 80 installed along the urea water supply line 69. After that, the engine cooling water that has finished supplying heat and has reached a relatively low temperature reaches the diesel engine 8 through the fourth portion 80d of the pipe 80. As a result, the antifreeze mechanism supplies heat to the urea water and the urea water supply line 69 in the urea water tank 20 by using the engine cooling water, and prevents the urea water tank 20 and the urea water supply line 69 from freezing. be able to.

Next, with reference to FIG. 4, the arrangement of various parts centering on the urea water tank 20 in the upper swing body 2 of the excavator will be described.

FIG. 4 is a right side view of the upper swing body 2 near the mounting position of the urea water tank 20.

As described above, the urea water tank 20 is mounted on the swivel frame 2a on the right front side of the upper swivel body 2.

A pair of left and right support brackets 17 for attaching the boom 4 are erected on the swivel frame 2a at the center of the front portion of the upper swivel body 2. One end of the boom 4 is arranged between the pair of left and right support brackets 17, and the boom foot pin 100 is fixed so as to penetrate the right support bracket 17, the boom 4, and the left support bracket 17. As a result, the boom 4 is pivotally attached to the upper swing body 2.

The boom foot pin 100 is provided with a rotation stopper 102 for preventing rotation. Specifically, the detent 102 is welded to the boom foot pin 100 and is inserted into the boss 104 provided on the support bracket 17 to prevent the boom foot pin 100 from rotating.

The support bracket 17 is arranged in the front-rear direction so as to overlap the front-rear position where the urea water tank 20 is arranged. That is, the urea water tank 20 is arranged on the right side of the support bracket 17 (specifically, the right support bracket 17). The upper end position of the urea water tank 20 including various parts to be attached is below the arrangement position of the boom foot pin 100. As a result, the boom foot pin 100 can be inserted into or pulled out from the insertion holes of the support bracket 17 and the boom 4 while the urea water tank 20 is mounted on the upper swing body 2.

Further, the urea water tank 20 is arranged adjacent to the front of the fuel tank 19 on the swivel frame 2a on the right front side of the upper swivel body 2. Further, the urea water tank 20 is arranged adjacent to the rear of the tool box 21 arranged at the front end portion of the upper swing body 2. That is, the urea water tank 20 is arranged between the tool box 21 and the fuel tank 19 in the front-rear direction on the swivel frame 2a on the right front side of the upper swivel body 2.

In the tool box 21 adjacent to the front of the urea water tank 20, in addition to the tools necessary for maintenance and inspection of the excavator, for example, an electric device such as a refueling pump 140 may be housed.

Next, the basic configuration of the urea water tank 20 will be described with reference to FIG.

FIG. 5 is a perspective view showing an example of the configuration of the urea water tank 20, and specifically, is a perspective view of the urea water tank 20 viewed from diagonally upper right and front.

As shown in FIG. 5, the urea water tank 20 includes a tank body 20a having a substantially rectangular cross section and a substantially box shape as a whole, and a tank storage container 12 for storing and holding the tank body 20a. The tank body 20a is made of resin, for example, and the tank storage container 12 is made of steel plate, for example. The urea water tank 20 is fixed to the upper swivel body 2 by, for example, fastening the tank storage container 12 to the swivel frame 2a (see FIG. 4).

The tank storage container 12 includes a tank reinforcing member 15 that holds the tank body 20a from below, and a tank bracket 26 that holds the tank body 20a from above.

An inclined surface 20b is formed on the upper part of the front side of the tank body 20a. Specifically, the inclined surface 20b is inclined in the manner of rising backward (that is, falling forward).

The inclined surface 20b is provided with an opening (liquid supply port) for supplying urea water to the tank body 20a, and a filler 30 is attached to the liquid supply port. The urea water is replenished in the tank body 20a via the filler 30.

Further, a level gauge 28 is provided on the inclined surface 20b. The level gauge 28 displays the liquid level height of the urea water in the tank body 20a. Specifically, the internal space of the level gauge 28 having a substantially circular tube shape communicates with the inside of the tank body 20a at the upper end and the lower end. Therefore, when the liquid level height of the urea water in the tank body 20a is higher than the lower end position of the level gauge 28, a part of the urea water flows into the level gauge 28, and the liquid level height is displayed on the level gauge 28. Will be done. The operator can prevent the outflow of urea water by replenishing the urea water while looking at the level gauge 28 during the urea water replenishment work.

Recesses 20c are formed on the left and right side surfaces of the tank body 20a. The recess 20c is provided with a recess substantially parallel to the bottom surface of the urea water tank 20 (tank body 20a), that is, in the horizontal direction. Therefore, the operator can grasp the urea water tank 20 (tank body 20a) by inserting his / her hands into the recess 20c from the left and right. Further, the tank body 20a has a substantially rectangular shape having a short side in the front-rear direction (X1, X2 directions in the figure) and a long side in the left-right direction (Y1, Y2 directions in the figure) in a plan view. The recess 20c is provided on the side surface on the short side (that is, the left and right side surfaces). Therefore, when the worker lifts the urea water tank 20 (tank body 20a), a force is easily applied, and the urea water tank 20 can be attached and detached more easily.

An opening (not shown) is provided on the upper surface of the tank body 20a, and a lid unit 40 for closing the opening is provided in the opening.

A urea water remaining amount sensor 74 is attached to the lid unit 40, and a communication line 74b for communicably connecting the urea water remaining amount sensor 74 and the urea water remaining amount sensor controller 74a is provided on the upper surface thereof. It is attached. Further, the lid unit 40 is provided with a plurality of through holes penetrating between the upper surface and the lower surface, that is, between the outside and the inside of the urea water tank 20, and is a pipe for engine cooling water that heats the urea water. 80, a urea water supply line 69, a urea water return line 78, and the like are inserted. That is, the pipe 80, the urea water supply line 69, the urea water return line 78, etc. penetrate between the inside and the outside of the urea water tank 20 in the lid unit 40.

The urea water return line 78 is used to return unused urea water to the urea water tank 20 that was not supplied from the urea water supply pump 70 to the urea water injection valve 68.

Further, the urea water tank 20 is provided with an air bleeding pipe 90 for communicating the internal air (inside air) and the outside air (outside air) of the urea water tank 20 (tank body 20a).

Here, when an air bleeding pipe for communicating the inside air and the outside air of the urea water tank 20 is provided on the upper surface of the tank body 20a in a normal manner with respect to the urea water tank 20, the inside of the urea water tank 20 The end of the air bleeding pipe may be submerged under the surface of urea water. Then, for example, when the excavator is keyed off, unused urea water is returned from the exhaust gas treatment device 10 (specifically, the urea water supply line 69) to the urea water tank 20, and the urea water is increased in response to an increase in internal pressure. May leak to the outside of the urea water tank 20 through the air vent pipe. In particular, in a situation where the tool box 21 is arranged adjacent to the urea water tank 20 as in the present embodiment, the urea water leaked from the tool or the electric device such as the refueling pump 140 housed in the tool box 21 is discharged. There is a high possibility that it will become unusable after being bathed. Therefore, in the present embodiment, the air bleeding pipe 90 is provided in the filler 30 of the urea water tank 20 to suppress the leakage of urea water from the air bleeding pipe 90. Hereinafter, the specific structure of the urea water tank 20 including the arrangement structure of the air bleeding pipe 90 will be described with reference to FIGS. 6 and 7.

FIG. 6 is a cross-sectional view showing an example of the configuration of the urea water tank 20, and specifically, is a right side sectional view of the urea water tank 20. FIG. 7 is a cross-sectional view showing an example of the configuration of the filler 30 in the urea water tank 20, and specifically, is an enlarged view of a portion centered on the filler 30 in the cross-sectional view of the urea water tank 20 of FIG. ..

As shown in FIGS. 6 and 7, the filler 30 has a substantially cylindrical shape as a whole and penetrates the inclined surface 20b of the urea water tank 20. The filler 30 includes a filler pipe 31, a filler body 32, a connecting pipe 33, a filler bracket 34, a filler cap 35, and the like.

The filler pipe 31 has a substantially cylindrical shape, and is made of, for example, the same resin as the tank body 20a. The filler pipe 31 is inserted into the tank through a liquid supply port formed on the inclined surface 20b of the tank body 20a, and is attached to the inclined surface 20b of the tank body 20a via a flange portion 31a provided on the outer peripheral portion. Most of the filler pipe 31 (in the drawing, the longer portion in the axial direction of the filler pipe 31 with the flange portion 31a as a boundary) protrudes inside the tank body 20a. In other words, the end of the filler pipe 31 projects obliquely downward and rearward inside the tank body 20a. Further, the remaining portion of the filler pipe 31 (the portion shorter in the axial direction of the filler pipe 31 with the flange portion 31a as a boundary in the drawing) protrudes from the liquid supply port to the outside of the tank body 20a. In other words, the end of the filler pipe 31 projects obliquely upward and forward outside the tank body 20a.

The bonding mode between the flange portion 31a and the tank body 20a may be bolt fastening, welding, or the like.

The filler body 32 has a substantially cylindrical shape with an inner diameter and an outer diameter similar to that of the filler pipe 31, and is made of, for example, metal or resin. One end of the filler body 32 is connected to the end of the filler pipe 31 via a connecting pipe 33, and the other end (opening) is closed by the filler cap 35. As a result, the filler pipe 31 is attached to the tank body 20a via the connecting pipe 33 and the filler pipe 31. Further, the operator can replenish the urea water tank 20 through the filler pipe 31 by injecting urea water from the opening of the filler body 32 from which the filler cap 35 has been removed.

Further, a filler bracket 34 is attached to the filler body 32 by, for example, a bolt or the like. The filler bracket 34 is made of, for example, metal or resin, and is fixed to the upper surface and the inclined surface 20b of the tank body 20a. As a result, the filler body 32 is attached to the tank body 20a via the filler bracket 34. Therefore, by providing the filler bracket 34 in the filler 30, the strength (rigidity) of the filler 30 as a whole can be increased. Therefore, for example, when the urea water is replenished to the urea water tank 20, the worker presses the replenishment gun against the filler 30 while entrusting the body, so that a large external force acts on the filler 30. Even in this case, it is possible to suppress a situation in which the filler 30 is damaged due to deformation or the like.

A strainer 32a is attached to the opening of the filler body 32. The strainer 32a has a substantially cylindrical shape with an outer diameter smaller than the inner diameter of the cylindrical filler main body 32, and one end is opened and the other end is closed. By injecting urea water into the open end of the strainer 32a provided at the opening of the filler body 32 by the operator, the urea water from which foreign matter has been removed at the side surface of the strainer 32a and the closed other end is filled with the filler. It is replenished in the tank body 20a through the pipe 31. As a result, it is possible to prevent foreign matter and the like from being mixed into the urea water tank 20 (tank body 20a) from the opening of the filler body 32.

The connecting pipe 33 has a cylindrical shape having an inner diameter substantially equal to the outer diameter of the filler pipe 31 and the filler main body 32, and the end of the filler pipe 31 is inserted into one end thereof and the other end thereof. , The filler body 32 is inserted. Further, a band 33a is wound around the outer periphery of the portion where the filler pipe 31 and the filler body 32 are inserted at both ends of the connecting pipe 33. As a result, the connecting pipe 33 is fixed to the filler pipe 31 and the filler body 32. In other words, the filler pipe 31 and the filler body 32 are integrally connected through the connecting pipe 33. The connecting pipe 33 may be, for example, a flexible synthetic resin pipe. As a result, even if a relative position shift occurs between the filler pipe 31 and the filler body 32 for some reason (for example, manufacturing error, physical external force, temperature change), the position shift is absorbed. be able to.

The filler cap 35 is detachably attached to the opening of the filler body 32 and closes the opening. The filler cap 35 is screwed or fitted into, for example, the opening of the filler body 32.

When the filler cap 35 is screwed to the opening of the filler body 32, the filler cap 35 is naturally screwed to the inner peripheral surface or the outer peripheral surface adjacent to the opening of the filler body 32. A possible thread is formed.

When the operator replenishes the urea water tank 20 (tank body 20a) with the urea water from the filler 30, the liquid level of the urea water in the urea water tank 20 gradually rises. Then, when the liquid level reaches the upper end of the opening at the end of the filler pipe 31 (that is, the full water level LV), the rise of the liquid level inside the urea water tank 20 is stopped, and the urea water supply is further continued. Then, only the liquid level inside the filler 30 rises. In the present embodiment, since the air vent pipe 90 is not provided in the tank body 20a, the inside of the urea water tank 20 (tank body 20a) is blocked from the outside air when the urea water level reaches the full water level LV. This is because it becomes a state.

Further, the upper end of the opening at the end of the filler pipe 31 is below the upper end of the level gauge 28. Therefore, the level gauge 28 can display the full water level LV of the urea water in the urea water tank 20 to the operator.

The upper end of the opening at the end of the filler pipe 31 may be at least substantially the same height as the upper end of the level gauge 28, whereby the level gauge 28 is filled with urea water in the urea water tank 20. The liquid level LV can be displayed to the operator.

Further, in the urea water tank 20 (tank body 20a), an air layer A is formed above the full water level LV inside the urea water tank 20 (tank body 20a). Therefore, for example, even if the urea water inside the urea water tank 20 freezes and expands in an extremely low temperature environment, damage to the urea water tank 20 (tank body 20a) can be avoided.

Further, the filler 30 is provided with an air bleeding pipe 90 as described above. The air bleeding pipe 90 includes an insertion portion 91 and an air bleeding hose 92.

The insertion portion 91 has a substantially cylindrical shape. The insertion portion 91 is erected on the outer peripheral surface of the filler main body 32, one end thereof is opened inside the filler main body 32, and the other end portion is open to the outside of the filler main body 32. That is, the insertion portion 91 communicates between the inside and the outside of the substantially cylindrical shape of the filler body 32.

The insertion portion 91 may be integrally molded with the filler main body 32, or may be molded separately from the filler main body 32 and then bonded to the outer peripheral surface of the filler main body 32 by welding or the like.

The air bleeding hose 92 is made of, for example, a flexible synthetic resin, and an insertion portion 91 is inserted into one end thereof, and the other end portion is open to the atmosphere. As a result, the internal space of the filler 30 connected to the inside of the tank body 20a (specifically, the internal space of the filler body 32 having a substantially cylindrical shape, the connecting pipe 33, and the filler pipe 31) and the outside of the tank body 20a There is communication between them. Therefore, in response to fluctuations in the internal pressure of the urea water tank 20, the inside air of the urea water tank 20 (including the air in the internal space of the filler 30) can be released to the outside through the air vent pipe 90, or the inside of the urea water tank 20 can be released. Outside air can be introduced into (including the internal space of the filler 30).

As described above, in the present embodiment, since the air bleeding pipe 90 is provided in the filler 30, the end portion of the air bleeding pipe 90 inside the urea water tank 20 is less likely to be immersed in the urea water, and the urea from the air bleeding pipe 90 Leakage of water can be suppressed.

Further, in the present embodiment, as described above, the urea water level in the filler 30 rises after the urea water level in the urea water tank 20 reaches the full water level LV. Therefore, in the replenishment work while checking the level gauge 28, the end portion of the air bleeding pipe 90 is hardly immersed in the urea water, and the leakage of the urea water from the air bleeding pipe 90 can be further suppressed. Even if the operator neglects to check the level gauge 28, the worker confirms that the urea water level in the filler 30 rises from the opening of the filler body 32 when the worker confirms the rise. Urea water supply can be stopped. Therefore, even in such a situation, it is possible to prevent the end of the air bleeding pipe 90 from being immersed in urea water, and further suppress the leakage of urea water from the air bleeding pipe 90.

Further, in the present embodiment, since the air bleeding pipe 90 is provided not in the tank body 20a but in the filler 30, it is possible to prevent the liquid level inside the urea water tank 20 from rising above the full liquid level LV. Therefore, for example, when the liquid level of urea water rises above the full water level LV, the detection value of the urea water remaining amount sensor 74 is 100% of the urea water remaining amount ratio even though urea water is used. It is possible to prevent a situation in which an abnormality of the urea water remaining amount sensor 74 is erroneously detected by continuing with the value corresponding to.

Although the embodiments for carrying out the present invention have been described in detail above, the present invention is not limited to such specific embodiments, and various aspects are within the scope of the gist of the present invention described in the claims. Can be transformed / changed.

1 Lower traveling body 2 Upper turning body 3 Cab 4 Boom 5 Arm 6 Bucket 7 Engine room 8 Diesel engine (engine)
9 Exhaust pipe 10 Exhaust gas treatment device 11 Cooling fan 12 Tank storage container 13 Heat exchanger unit 14 Swing frame 15 Tank reinforcement member 17 Support bracket 19 Fuel tank 20 Urea water tank (storage tank)
20a Tank body 20b Inclined surface 20c Recess 21 Tool box 26 Tank bracket 28 Level gauge (gauge)
30 Filler 31 Filler pipe 32 Filler body 32a Strainer 33 Connection pipe 33a Band 34 Filler bracket 35 Filler cap 40 Lid unit 60 Engine control module 61 Turbocharger 63 Aircleaner 64 Intake pipe 65 Intercooler 66 Diesel particulate filter 67 Selective reduction catalyst 68 Urea water injection valve 69 Urea water supply line 70 Urea water supply pump 71 Strainer 72,73 NOx sensor 74 Urea water remaining amount sensor 74a Urea water remaining amount sensor controller 74b Communication line 75 Urea water system controller 76 Excavator controller 77 Monitor 78 Urea water Return line 80 Piping 80a First part 80b Second part 80c Third part 80d Fourth part 90 Air bleeding pipe 91 Insertion part 92 Air bleeding hose 100 Boom foot pin 102 Anti-rotation 104 Boss 140 Refueling pump A Air layer LV Full water surface

Claims (6)

A storage tank that stores the treatment agent that purifies the exhaust gas of the engine with the opening closed by the filler cap ,
Provided so as to be inserted into the interior of the storage tank to replenish the processing agent, a filler Ru with the filler cap to the end,
In case of supplying the processing agent from said opening when opening the said filler cap, only the interior of the filler of the internal of the internal and the storage tank of the filler is provided in the filler so as to communicate with the atmosphere Equipped with an air bleeding pipe,
Excavator. Attached to the storage tank and provided with a gauge indicating the liquid level in the storage tank.
The upper end of the filler opening in the storage tank is located at approximately the same height as the upper end of the gauge or below the upper end of the gauge.
The excavator according to claim 1. A recess is formed on the side surface of the storage tank substantially parallel to the bottom surface of the storage tank.
The excavator according to claim 1 or 2. The storage tank has a substantially rectangular shape having a short side and a long side in a plan view.
The recess is formed on the side surface on the short side.
The excavator according to claim 3. A strainer is provided in the filler.
The excavator according to any one of claims 1 to 4. Inside the storage tank, an air layer is formed above the liquid level when the tank is full.
The excavator according to any one of claims 1 to 5.

Images