JP5214557B2 - Hydraulic oil tank device - Google Patents

Description

  The present invention relates to a hydraulic oil tank apparatus that is suitably used as a part of hydraulic equipment in various industrial machines including construction machines such as hydraulic excavators.

  In general, a construction machine such as a hydraulic excavator is provided with a self-propelled lower traveling body, an upper revolving body that is turnably mounted on the lower traveling body, and an upside-down movable structure provided on the front side of the upper revolving body. And a work device. The upper swing body is equipped with an engine for driving a hydraulic pump at the rear of the swing frame, and a cab, a fuel tank, a hydraulic oil tank, and the like are mounted on the front side of the swing frame.

  The hydraulic oil tank employed in this type of conventional technology includes a tank main body that stores the hydraulic oil, a return filter that removes foreign substances from the hydraulic oil returned into the tank main body, and the tank main body. And a suction filter for removing foreign matter in the hydraulic oil sucked out by the hydraulic pump (see, for example, Patent Document 1).

Japanese Utility Model Publication No. 6-73402

  By the way, in the prior art mentioned above, it is set as the structure which arrange | positions a return filter and a suction filter in a tank main body. For this reason, there is a problem that the structure of the hydraulic oil tank is complicated and workability at the time of maintenance and inspection is poor. In particular, when trying to maintain and inspect the return filter and suction filter in the tank body, there is a risk that some of the foreign matter adhering to the filter will fall off and be mixed into the hydraulic oil in the tank body. There is a problem that the burden increases.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a filter separated from the tank body, thereby simplifying the overall structure and improving workability during maintenance. It is an object of the present invention to provide a hydraulic oil tank device that can improve the performance.

In order to solve the above-described problem, the invention of claim 1 includes a tank body that contains hydraulic oil, and a filter case that is formed separately from the tank body and is detachably connected to the tank body. The filter case is divided into a return filter chamber and a suction filter chamber via a partition, and the return filter chamber of the filter case has a return for removing foreign matter from the hydraulic oil returned into the tank body. provided housing the filter, the the suction filter chamber has a structure in which Ru is provided housing the suction filter for removing foreign matter in hydraulic oil sucked out by the hydraulic pump from the tank body.

Further, according to the invention of claim 2, the filter case has a case body that is formed as a hollow cylindrical body and is disposed outside the tank body, and the partition portion is disposed above the case body. defining the two chambers below the upper chamber and the return filter chamber, the lower chamber has a configuration to said suction filter chamber.

  According to a third aspect of the present invention, the filter case has an external inlet for flowing hydraulic oil returned from an external hydraulic device into the return filter chamber, and after the foreign matter is removed by the return filter. A case outlet for returning the hydraulic oil to the tank body, a case inlet for flowing the hydraulic oil in the tank main body into the suction filter chamber, and the hydraulic pump removing the foreign oil by the suction filter And an external outlet that leads to the suction side.

  According to the invention of claim 4, a main body inlet for introducing hydraulic oil into the tank main body via a return filter in the filter case, and a hydraulic oil in the tank main body are led to the suction filter chamber. The main body outlet is provided.

  According to a fifth aspect of the present invention, the main body inlet is configured to open in the vicinity of the inner wall surface so that hydraulic oil flowing in from the filter case side flows along the inner wall surface of the tank body. Yes.

  Furthermore, according to the invention of claim 6, the tank body is formed by using a resin material, and the wall surface of the tank body is provided with a gauge wire for confirming the amount of hydraulic oil contained therein. Yes.

As described above, according to the invention of claim 1, the inside of the filter case formed separately from the tank body is defined by the return filter chamber and the suction filter chamber via the partition portion, the filter case for internally accommodating a return filter and suction filter with suction filter chamber, since the configuration of connecting wearing detachably with respect to the tank body separate tank a plurality of filters as in the prior art There is no need to provide the main body, and the structure of the tank main body can be simplified. A return filter can be stored in the return filter chamber of the filter case, and a suction filter can be stored in the suction filter chamber. In the maintenance for inspecting and inspecting the filter, it is not necessary to remove the filter from the tank body, so that the workability during maintenance can be improved. In addition, even if foreign matter adhering to the filter falls off, the foreign matter can be prevented from being mixed into the hydraulic oil in the tank body, and the hydraulic oil in the tank body can be kept clean.

  According to the invention of claim 2, the filter case has a case body and a partition part, and the case body can be defined as a return filter chamber and a suction filter chamber by the partition part. A return filter can be stored in the return filter chamber of the case body, and a suction filter can be stored in the suction filter chamber.

  According to the invention of claim 3, by connecting the external inlet of the filter case to an external hydraulic device via a pipe such as a hose, the hydraulic oil returned from the hydraulic device is supplied to the return filter chamber of the filter case. Can lead to. In the filter case, it is possible to return the hydraulic oil, which has been cleaned by removing foreign substances with a return filter, from the case outlet to the tank body. On the other hand, when the hydraulic oil in the tank body is sucked by an external hydraulic pump, the hydraulic oil can be guided from the case inlet of the filter case to the suction filter chamber. Can be led out from the external outlet to the suction side of the hydraulic pump.

  According to the invention of claim 4, it is possible to introduce the hydraulic oil from which foreign matter has been removed by the return filter in the filter case into the tank body from the main body inlet. Then, the hydraulic oil in the tank main body can be led out from the main body outlet to the suction filter chamber side of the filter case.

  Further, according to the invention of claim 5, since the main body inlet is configured to open in the vicinity of the inner wall surface of the tank body, the hydraulic oil from the filter case can thereby flow along the inner wall surface (side surface) of the tank body. The flow of the hydraulic oil in the tank body can be made smooth, and the defoaming effect that suppresses the generation of bubbles in the hydraulic oil can be exhibited.

  Furthermore, according to the invention of claim 6, the tank body can be formed as a resin tank using a resin material, and by providing a gauge wire on the wall surface of the tank body, the amount of hydraulic oil contained therein Alternatively, the remaining amount can be visually confirmed by comparing with the gauge line.

It is a front view which shows the hydraulic shovel provided with the hydraulic-oil tank apparatus by the 1st Embodiment of this invention. It is a front view which expands and shows a hydraulic-oil tank apparatus. It is sectional drawing which looked at the hydraulic-oil tank apparatus from the arrow III-III direction in FIG. It is sectional drawing which looked at the hydraulic-oil tank apparatus from the arrow IV-IV direction in FIG. It is a perspective view shown in the state before connecting the tank main body and filter case of a hydraulic oil tank device, respectively. It is sectional drawing in the same position as FIG. 3 which shows the hydraulic-oil tank apparatus by 2nd Embodiment.

  Hereinafter, a case where the hydraulic oil tank device according to the embodiment of the present invention is mounted on a small hydraulic excavator will be described as an example and described in detail with reference to the accompanying drawings.

  Here, FIG. 1 to FIG. 5 show a first embodiment of the present invention. In the figure, 1 is a small hydraulic excavator used for excavation work of earth and sand. The hydraulic excavator 1 includes a self-propelled crawler-type lower traveling body 2, an upper revolving body 3 that is swingably mounted on the lower traveling body 2, and can be raised and lowered to the front side of the upper revolving body 3. This is roughly constituted by the working device 4 provided.

  The upper swing body 3 constitutes a vehicle body together with the lower traveling body 2. The upper swing body 3 includes a swing frame 5, a counterweight 6, an exterior cover 7, a cab 8, and the like which will be described later.

  Reference numeral 5 denotes a revolving frame of the upper revolving structure 3, and the revolving frame 5 is mounted on the lower traveling body 2 via a revolving device (not shown). A counterweight 6 is provided on the rear side of the turning frame 5, and a cab 8 described later is provided on the left front side. The revolving frame 5 is provided with an exterior cover 7 positioned between the counterweight 6 and the cab 8. The exterior cover 7 together with the revolving frame 5, the counterweight 6, and the cab 8 defines a space that accommodates an engine 9, a hydraulic oil tank device 10, and the like to be described later.

  Reference numeral 8 denotes a cab mounted on the left front side of the revolving frame 5. The cab 8 is used by an operator. Inside the cab 8, a driver's seat on which an operator is seated and various operation levers (all not shown) are arranged.

  Reference numeral 9 denotes an engine as a prime mover disposed in a lateral state on the rear side of the revolving frame 5, and the engine 9 is configured by using, for example, a diesel engine and rotationally drives a hydraulic pump (not shown) or the like. It is. The hydraulic pump sucks hydraulic oil from a hydraulic oil tank device 10 described later, and supplies high-pressure oil to a hydraulic actuator such as a hydraulic cylinder or a hydraulic motor.

  Reference numeral 10 denotes a hydraulic oil tank apparatus employed in the present embodiment. The hydraulic oil tank apparatus 10 includes a tank body 11 and a filter case 18 which will be described later, as shown in FIGS. Yes. The hydraulic oil tank device 10 is disposed on the revolving frame 5 of the upper revolving structure 3 and disposed in the exterior cover 7 as shown in FIG.

  Reference numeral 11 denotes a tank main body that contains hydraulic oil. As shown in FIGS. 2 to 4, the tank main body 11 is a rectangular box shape (box shape) using a synthetic resin material such as polypropylene or acrylic resin. It is formed as a resin tank. The tank body 11 includes a bottom surface 11A, an upper surface 11B, front and rear side surfaces 11C and 11D, and left and right side surfaces 11E and 11F. Among these, the front and rear side surfaces 11 </ b> C and 11 </ b> D and the left and right side surfaces 11 </ b> E and 11 </ b> F constitute an inner wall surface of the tank body 11.

  An inlet 12 for injecting hydraulic oil L into the tank body 11 is provided on the upper surface 11B of the tank body 11 so as to protrude upward. A cap 13 is detachably screwed into the inlet 12. ing. And the cap 13 is comprised as a cap with an air breather, and has the function to discharge | emit the air in the tank main body 11 outside, and to maintain an internal pressure in an atmospheric pressure state.

  In addition, a viewing window 14 is formed on the wall surface (for example, the side surface 11F) of the tank body 11 in order to check the amount of hydraulic oil L contained therein as shown in FIG. For example, three gauge wires 15A, 15B, and 15C are provided at regular intervals.

  In this case, the hydraulic fluid L is filled in the tank body 11 to the level of the uppermost gauge line 15A among the gauge lines 15A to 15C. However, when the amount of hydraulic oil gradually decreases after long-term use (operation of the hydraulic excavator 1) and the liquid level of the hydraulic oil L decreases to the level of the lowermost gauge line 15C, it enters the tank body 11. The hydraulic oil L is replenished from the inlet 12 with the cap 13 removed.

  Reference numeral 16 denotes a main body inlet for introducing hydraulic oil into the tank main body 11. The main body inlet 16 projects linearly from the side surface 11D of the tank main body 11 toward the rear (the filter case 18 side described later), for example. The height position is equivalent to or slightly lower than the gauge line 15A as shown in FIG. As shown in FIG. 3, the main body inlet 16 is disposed at a position near the corners of the side surface 11D and the side surface 11E of the tank main body 11, and opens into the side surface 11D near the side surface 11E.

  Therefore, the hydraulic oil flowing into the tank body 11 from the body inlet 16 flows along the side surface 11E and the side surface 11C as the inner wall surface of the tank body 11, as shown by the arrow A in FIG. The defoaming effect described later is exhibited. Further, a reinforcing metal pipe 16A is integrally formed inside the main body inlet 16 by means such as insert molding.

  Reference numeral 17 denotes a main body outlet through which hydraulic oil in the tank body 11 is led out. The main body outlet 17 is positioned below the main body inlet 16 as shown in FIGS. 2 and 4, that is, the bottom surface of the tank body 11. It is arranged at a position slightly above 11A. The main body outlet 17 protrudes linearly from, for example, the side surface 11D of the tank main body 11 toward the rear (the filter case 18 side described later), and is connected to the case inlet 26 described later via a connecting hose 27. . Further, a reinforcing metal pipe 17A is integrally formed inside the main body outlet 17 by means such as insert molding.

  Reference numeral 18 denotes a filter case formed separately from the tank body 11, and the filter case 18 is formed as a cylindrical body having a hollow inside as shown in FIG. 4 and is disposed outside the tank body 11. 18A and the partition part 18B which consists of a partition provided in the height direction intermediate position of this case body 18A are comprised. The partition portion 18B defines the inside of the case body 18A into two upper and lower chambers, that is, a return filter chamber 19 as an upper chamber and a suction filter chamber 20 as a lower chamber.

  Further, the filter case 18 has an upper lid portion 18C in which the upper end side of the case body 18A is detachably closed using bolts, nuts, and the like, and the lower end side of the case body 18A is detachable using other bolts, nuts, etc. And a closed bottom lid 18D. The return filter chamber 19 in the case body 18A is formed between the partition portion 18B and the upper lid portion 18C, and the suction filter chamber 20 is formed between the partition portion 18B and the bottom lid portion 18D. is there.

  Reference numeral 21 denotes a return filter housed in the return filter chamber 19 of the filter case 18, and the return filter 21 is configured by using a cylindrical filter element as shown in FIG. It is attached to the lower surface of the. The return filter 21 is disposed so as to hang downward from the upper lid portion 18C in the return filter chamber 19, and the lower surface side thereof is closed by a closing plate 21A.

  Here, the working oil introduced into the return filter chamber 19 from the external inlet 23 described later flows from the inner side in the radial direction of the return filter 21 toward the outer side, thereby removing (filtering) foreign matter and cleaning. Is done. When maintaining / inspecting the return filter 21, the upper cover 18C of the filter case 18 is detached from the case body 18A via a bolt or the like, thereby removing the return filter 21 from the case body 18A.

  A suction filter 22 is housed and provided in the suction filter chamber 20 of the filter case 18, and the suction filter 22 is configured using a cylindrical filter element as shown in FIG. It is attached to the upper surface of the part 18D. The suction filter 22 protrudes upward from the bottom lid 18D and is disposed in the suction filter chamber 20, and the upper surface side thereof is closed by a closing plate 22A.

  Here, the working oil introduced into the suction filter chamber 20 from the case inlet 26 described later flows from the radially outer side to the inner side of the suction filter 22, thereby removing (filtering) foreign matters and cleaning. Is done. When the suction filter 22 is maintained and inspected, the bottom cover 18D of the filter case 18 is detached from the case body 18A via a bolt or the like, thereby removing the suction filter 22 from the case body 18A.

  Reference numeral 23 denotes an external inflow port provided on the upper end side of the filter case 18, and the external inflow port 23 is provided so as to protrude upward from the upper lid portion 18C as shown in FIG. The external inflow port 23 guides hydraulic oil returned from an external hydraulic device (for example, a hydraulic cylinder, a hydraulic motor, a directional control valve, etc.) into the return filter chamber 19 of the filter case 18.

  Reference numeral 24 denotes a case outlet provided on the side surface of the filter case 18, and the case outlet 24 is provided so as to protrude radially outward from the case body 18A as shown in FIG. 16 (see FIG. 2). And the case outflow port 24 is connected to the main body inflow port 16 of the tank main body 11 using the connection hose 25 as a connection tool. The connecting hose 25 is connected between the main body inlet 16 and the case outlet 24 in a state of being bent in a substantially “<” shape.

  Here, the working oil, which has been cleaned by removing foreign matter by the return filter 21 in the filter case 18, flows from the case outlet 24 toward the main body inlet 16 of the tank body 11, and an arrow in FIG. 3. As shown by A, it flows along the side surface 11E and the side surface 11C of the tank body 11.

  Reference numeral 26 denotes a case inlet provided on the side surface of the filter case 18, and the case inlet 26 is located at a position and a direction different from the case outlet 24 as shown in FIG. Protrusively provided. The case inlet 26 is positioned below the case outlet 24 as shown in FIGS. 2 and 4, and is disposed at the same height as the main body outlet 17 of the tank body 11.

  Here, the case inlet 26 is connected to the main body outlet 17 of the tank main body 11 using a connecting hose 27 as a connector. The hydraulic oil in the tank main body 11 is guided from the main body outlet 17 into the suction filter chamber 20 of the filter case 18 through the connecting hose 27 and the case inlet 26, and the suction filter 22 in the suction filter chamber 20. This removes (filters) foreign matter in the hydraulic oil.

  Reference numeral 28 denotes an external outlet provided on the lower end side of the filter case 18, and the external outlet 28 protrudes downward from the bottom lid portion 18D as shown in FIG. The external outlet 28 is connected to the suction side of the hydraulic pump via a suction pipe (not shown). Here, the hydraulic oil cleaned by the suction filter 22 in the filter case 18 is sucked (derived) from the external outlet 28 to the suction side of the hydraulic pump by the rotation of the hydraulic pump.

  The hydraulic oil tank device 10 mounted on the hydraulic excavator 1 according to the present embodiment has the above-described configuration, and the operation thereof will be described next.

  First, the operator of the hydraulic excavator 1 gets on the cab 8 of the upper swing body 3, starts the engine 9, and drives a hydraulic pump (not shown). As a result, the hydraulic oil in the tank body 11 is guided from the main body outlet 17 into the suction filter chamber 20 of the filter case 18 via the connection hose 27 and the case inlet 26, and from the external outlet 28 of the filter case 18. Suction (derived) to the suction side of the hydraulic pump.

  At this time, in the suction filter chamber 20 of the filter case 18, foreign matter in the hydraulic oil is removed (filtered) by the suction filter 22, and the cleaned hydraulic oil is passed from the external outlet 28 of the filter case 18 to the hydraulic pump. And sucked. Then, the hydraulic pump discharges the sucked hydraulic oil as pressure oil, thereby supplying the pressure oil to an external hydraulic device (for example, a hydraulic actuator such as a hydraulic cylinder or a hydraulic motor).

  On the other hand, the hydraulic oil returned as return oil from the hydraulic actuator is introduced into the return filter chamber 19 from the external inlet 23 side of the filter case 18 via, for example, an oil cooler, a return pipe (both not shown) and the like. It is burned. Here, the hydraulic oil (return oil) guided into the return filter chamber 19 of the filter case 18 is cleaned by removing (filtering) foreign matters in the oil liquid by the return filter 21 in the return filter chamber 19. In this state, the air flows into the tank body 11 from the case outlet 24 of the filter case 18 through the connecting hose 25 and the main body inlet 16.

  Then, the hydraulic oil flowing into the tank main body 11 from the main body inlet 16 flows in the direction of arrow A along the side surface 11E and the side surface 11C as shown in FIG. The flow of oil can be smoothed, and the defoaming effect that suppresses the generation of bubbles in the hydraulic oil can be exhibited.

  Further, a viewing window 14 is formed on the wall surface (for example, the side surface 11F) of the tank body 11 in order to check the amount of the hydraulic oil L accommodated therein as shown in FIG. In the vicinity of the viewing window 14, a plurality of gauge wires 15A, 15B, and 15C are provided at regular intervals. Thereby, the oil amount or the remaining amount of the hydraulic oil stored in the tank main body 11 can be confirmed by visual comparison with the gauge wires 15A, 15B, 15C.

  Thus, according to the present embodiment, the filter case 18 separate from the tank body 11 is provided outside the tank body 11, and the return filter 21 and the suction filter 22 are provided inside the filter case 18. It is set as the structure accommodated separately. Thereby, compared with a prior art, the structure of the tank main body 11 can be simplified greatly, and the tank main body 11 can be formed as a box body of a simple shape as a resin tank.

  At the time of maintenance for inspecting and inspecting the filters 21 and 22, it is not necessary to remove the filters 21 and 22 from the tank body 11, so that workability at the time of maintenance can be improved. In addition, even if foreign matter adhering to the filters 21 and 22 falls off, the foreign matter can be prevented from entering the hydraulic oil in the tank body 11, and the hydraulic oil in the tank body 11 can be kept clean. be able to.

  Further, since the filter case 18 employed in the present embodiment has a case body 18A, a partition portion 18B, an upper lid portion 18C, and a bottom lid portion 18D, the partition portion 18B and the upper lid portion are provided in the case body 18A. A return filter chamber 19 in which the return filter 21 is accommodated can be defined between the suction filter chamber 18C and a suction filter chamber 20 in which the suction filter 22 is accommodated is defined between the partition portion 18B and the bottom lid portion 18D. be able to.

  When maintaining / inspecting the return filter 21 in the filter case 18, the upper lid portion 18C of the filter case 18 is detached from the case body 18A via a bolt or the like. Thereby, the return filter 21 can be easily taken out from the case body 18A, and the maintenance work for the return filter 21 can be easily performed.

  When maintaining / inspecting the suction filter 22 in the filter case 18, the bottom cover portion 18D of the filter case 18 is detached from the case body 18A via a bolt or the like. Thereby, the suction filter 22 can be easily taken out from the case body 18A, and the maintenance work for the suction filter 22 can be simplified.

  On the other hand, the main body inlet 16 provided in the tank main body 11 is disposed at a position near the corner between the side surface 11D and the side surface 11E of the tank main body 11 as shown in FIG. 25, the hydraulic oil flowing into the tank body 11 through the body inlet 16 is circulated in the direction of arrow A in FIG. 3 along the side surface 11E and the side surface 11C of the tank body 11. Thereby, the flow of the hydraulic oil in the tank main body 11 can be made smooth, and the defoaming effect which suppresses generation | occurrence | production of a bubble in hydraulic fluid can be exhibited.

  Further, a viewing window 14 is formed on the wall surface (for example, the side surface 11F) of the tank body 11 as shown in FIG. 2, and a plurality of gauge wires 15A, 15B, 15C are provided in the vicinity of the viewing window 14. It is said. Thus, for example, when the maintenance worker checks the amount of the hydraulic oil L stored in the tank body 11, the maintenance operator can visually check the remaining amount of hydraulic oil as compared with the gauge wires 15A, 15B, and 15C through the observation window 14. The amount can be confirmed.

  Next, FIG. 6 shows a second embodiment of the present invention, and the feature of this embodiment is that the main body inlet provided in the tank main body is inclined and protrudes from the tank main body. is there. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In the figure, 31 is a main body inlet employed in the second embodiment, and the main body inlet 31 is configured in substantially the same manner as the main body inlet 16 described in the first embodiment. It arrange | positions in the position close | similar to the corner of side 11D and side 11E. Further, a reinforcing metal pipe 31A is integrally formed inside the main body inlet 31 by means such as insert molding.

  However, the main body inlet 31 in this case is different from the first embodiment in that the main body inlet 31 protrudes obliquely from the side surface 11D of the tank body 11 toward the case outlet 32 described later. Then, by inclining the main body inlet 31 with respect to the side surface 11D of the tank main body 11, the hydraulic oil flowing into the tank main body 11 from the main body inlet 31 flows into the side 11E in the direction of arrow A in FIG. It flows smoothly along the side surface 11C and exhibits a defoaming effect.

  Reference numeral 32 denotes a case outlet provided on a side surface of the filter case 18, and the case outlet 32 extends radially outward from the case body 18A in substantially the same manner as the case outlet 24 described in the first embodiment. It protrudes and is arranged at a height position equivalent to the main body inlet 31 of the tank main body 11. However, the case outlet 32 in this case is located on the same straight line as the main body inlet 31 protruding obliquely from the side surface 11D of the tank main body 11, and is formed to face the main body inlet 31 with a gap. This is different from the first embodiment.

  Reference numeral 33 denotes a connecting hose as a connection tool. The connecting hose 33 connects the main body inlet 31 of the tank body 11 and the case outlet 32 of the filter case 18 and extends linearly between the two. Is formed. For this reason, the hydraulic oil flowing from the case outlet 32 of the filter case 18 toward the main body inlet 31 of the tank body 11 smoothly flows linearly in the connecting hose 33, and the flow resistance is suppressed to a small value.

  Thus, also in the second embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment described above. In particular, in the second embodiment, the main body inlet 31 protrudes obliquely from the side surface 11D of the tank body 11 and is opposed to the case outlet 32 of the filter case 18 in a straight line. Such effects can be obtained.

  That is, the connecting hose 33 that connects the main body inlet 31 of the tank body 11 and the case outlet 32 of the filter case 18 can be formed by extending linearly between the two. For this reason, the hydraulic oil flowing from the case outlet 32 of the filter case 18 toward the main body inlet 31 of the tank body 11 can be smoothly circulated in the connecting hose 33, and the flow resistance can be kept small. Moreover, the defoaming effect can be exhibited.

  Further, the hydraulic oil that flows into the tank body 11 from the case outlet 32 of the filter case 18 through the connecting hose 33 and the body inlet 31 flows along the side surface 11E and the side surface 11C of the tank body 11 with the arrows in FIG. Circulates in the direction indicated by A. Thereby, the flow of the hydraulic oil in the tank main body 11 can be made smooth, and the defoaming effect which suppresses generation | occurrence | production of a bubble in hydraulic fluid can be exhibited.

  In the first and second embodiments, the case where the case body 18A of the filter case 18 is formed as a hollow cylindrical body has been described as an example. However, the present invention is not limited to this, and the case body of the filter case may be formed as a rectangular cylinder such as a triangle, a quadrangle, or a pentagon.

  Further, the tank body 11 is not limited to a rectangular box shape, and may be formed as a rectangular box such as a pentagon or a hexagon. On the other hand, the tank body 11 does not necessarily need to be a resin tank, and for example, a tank body having a can-making structure may be used.

  Furthermore, in each embodiment, the hydraulic oil tank apparatus 10 mounted on the small hydraulic excavator 1 has been described as an example. However, the present invention is not limited to this, and may be applied to, for example, a hydraulic excavator equipped with a wheel type lower traveling body made of tires or the like, or a hydraulic oil tank device mounted on a medium-sized or large-sized hydraulic excavator. In addition, the present invention may be applied to hydraulic oil tank devices mounted on various construction machines such as wheel loaders, bulldozers, hydraulic cranes, and the like.

1 Hydraulic excavator 2 Lower traveling body (vehicle body)
3 Upper swing body (car body)
5 Turning frame 9 Engine 10 Hydraulic oil tank device 11 Tank body 11A Bottom surface 11B Upper surface 11C, 11D, 11E, 11F Side surface (inner wall surface)
13 Cap 14 Viewing Window 15A, 15B, 15C Gauge Wire 16, 31 Main Body Inlet 17 Main Body Outlet 18 Filter Case 18A Case Main Body 18B Partition 18C Top Cover 18D Bottom Cover 19 Return Filter Chamber 20 Suction Filter Chamber 21 Return Filter 22 Suction filter 23 External inlet 24, 32 Case outlet 25, 27, 33 Connection hose 26 Case inlet 28 External outlet

Claims (6)

A tank body that contains hydraulic oil, and a filter case that is formed separately from the tank body and is detachably connected to the tank body;
The inside of the filter case is divided into a return filter chamber and a suction filter chamber via a partition part,
The return filter chamber of the filter case is provided with a return filter that removes foreign matter from the hydraulic oil returned into the tank body ,
The suction in the filter chamber, the tank houses a suction filter for removing foreign matter in hydraulic oil sucked out by the hydraulic pump from the body becomes a structure in which Ru provided hydraulic tank device. The filter case has a case body inside is disposed outside of the tank body is formed as a hollow cylindrical body, the partition section on the body the case, defining the two chambers under the The hydraulic oil tank apparatus according to claim 1, wherein the upper chamber is the return filter chamber and the lower chamber is the suction filter chamber.   The filter case includes an external inlet for flowing hydraulic oil returned from an external hydraulic device into the return filter chamber, and a case flow for returning the hydraulic oil after removing foreign matter by the return filter to the tank body. An outlet, a case inlet for flowing the hydraulic oil in the tank body into the suction filter chamber, and an external outlet for guiding the hydraulic oil from which foreign matter has been removed by the suction filter to the suction side of the hydraulic pump. The hydraulic oil tank device according to claim 1 or 2, wherein the hydraulic oil tank device is provided.   The tank body is provided with a main body inlet for introducing hydraulic oil through a return filter in the filter case and a main body outlet for leading the hydraulic oil in the tank main body to the suction filter chamber. The hydraulic oil tank apparatus according to claim 1, 2 or 3.   5. The hydraulic oil tank according to claim 4, wherein the main body inlet is configured to open in the vicinity of the inner wall surface in order to allow the hydraulic oil flowing in from the filter case side to flow along the inner wall surface of the tank body. apparatus.   The tank body is formed of a resin material, and a gauge wire for confirming the amount of hydraulic oil contained therein is provided on a wall surface of the tank body. Or the hydraulic oil tank device according to 5;

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