JP5733290B2 - Hydraulic oil tank device - Google Patents

Description

  The present invention relates to a hydraulic oil tank device installed in a construction machine such as an excavator.

  In construction machines such as excavators, a hydraulic oil tank that stores hydraulic oil and a hydraulic pump that supplies the hydraulic oil in the tank to the boom cylinder and other hydraulic actuators of the work attachment are installed. Are connected by a suction line.

  The configuration of a conventional hydraulic oil tank device is shown in FIGS.

  Taking a hydraulic oil tank device for an excavator as an example, a hydraulic oil tank (hereinafter simply referred to as a tank) 1 is formed in a rectangular parallelepiped box shape by a top plate, a bottom plate, and front, rear, left and right side plates.

  A deck structure (side deck) 2 having a beam structure in which a plurality of beams 2 a are combined vertically and horizontally is provided on the upper rotating body on which the tank 1 is mounted, and the hydraulic oil tank 1 is provided on the deck 2. Installed.

  In the tank 1, a strainer 3 for filtering hydraulic oil (not shown) is installed at the bottom, and the hydraulic oil discharged from the strainer 3 is supplied to a suction side of a hydraulic pump (not shown) by a suction line 4.

  The tank 1 is provided with other elements and members including a filter for filtering the return oil. However, since they are not directly related to the present invention, their illustration and description are omitted.

  The suction line 4 is connected to the strainer 3 by an L-shaped bent portion (usually an elbow is used for pressure loss reduction) 5 at one end and is connected to the hydraulic pump at the other end.

  FIG. 5 shows a case where the suction line 4 is disposed outside the tank, and the suction line 4 is passed outside the tank 1 into the thickness (height) of the deck 2 and sandwiches the tank bottom plate 1a. Thus, the strainer 3 and the bent portion 5 arranged inside and outside the tank are connected through a connection hole (not shown) (see Patent Document 1).

  However, according to this tank external piping system, the bent portion 5 does not fit within the deck thickness depending on the thickness of the deck 2 and the beam configuration, or the portion that passes through the deck 2 interferes with the beam 2a that constitutes the deck 2. In some cases, piping may not be possible in practice.

  Therefore, as shown in FIG. 6, there is a case where an in-tank piping system is employed in which a fixed length portion (inside tank portion) 4a on the tank side of the suction line 4 including the bent portion 5 is arranged in the tank 1 (patent). Reference 2).

  In this in-tank piping system, one end side of the tank inner portion 4a arranged at the tank inner bottom portion is connected to the strainer 3 by the bending portion 5, and the other end side is led out from the tank side surface and connected to the tank outer portion 4b.

  In the tank inner portion 4 a, for example, the bent portion 5 is welded to the tank bottom plate 1 a and is fixed to the inner bottom portion of the tank 1, thereby fulfilling the vibration suppressing function of the strainer 3.

  According to this in-tank piping system, there is no problem due to the relationship with the deck 2 as in the outside tank piping system, and the piping of the suction line 4 becomes easy.

Japanese Patent Laid-Open No. 5-187401 JP 2006-46016 A

  However, according to the conventional hydraulic oil tank device which adopts the in-tank piping system, as a result of disposing the tank inner portion 4a in the tank 1, the position of the strainer 3 which is a suction port for the hydraulic oil is raised, Since the minimum oil level of the tank rises, the tank 1 needs to be enlarged in order to secure the storage amount.

  Therefore, the present invention provides a hydraulic oil tank apparatus that can suppress the enlargement of the tank by lowering the strainer position while adopting the in-tank piping system.

As means for solving the above problems, in the present invention, a tank for storing hydraulic oil, a strainer provided at the bottom of the tank, and a suction for supplying the hydraulic oil discharged from the strainer to the suction side of the hydraulic pump In the hydraulic oil tank apparatus, the suction line has a tank inner portion disposed in the tank, and a tip end side of the tank inner portion is connected to the strainer via an L-shaped bent portion. A concave portion recessed downward on the bottom surface of the tank, and the tank inner portion of the suction line is disposed in a state where one end side portion including the bent portion is dropped into the concave portion , and the side surface of the bent portion A rib is provided so as to project outward, and this rib is welded and fixed to the bottom surface of the tank so that the tank inner portion of the suction line is tapped. Those fixed to the click.

  As described above, by dropping the one end side portion including the bent portion in the tank inner portion of the suction line into the concave portion, it is possible to suppress an increase in the height position of the strainer in the tank.

  By the way, as another configuration (configuration that does not depend on the recessed portion) for dropping one end side portion of the inner part of the tank below the tank bottom surface, a window hole is provided on the tank bottom surface, and one end side portion is dropped into this window hole. It is theoretically possible to take a configuration in which the entire circumference is sealed.

  However, in this case, since it is necessary to ensure the oil tightness of the dropped portion, it is necessary to process the window hole into a shape along the pipe with high accuracy. In addition, a highly accurate sealing operation is required, for example, welding the entire periphery of the tank to the bottom of the tank with the one end side portion dropped. For this reason, assembly is extremely troublesome.

  On the other hand, according to the present invention, since the concave portion is provided on the bottom surface of the tank and the pipe is dropped in a state where oil tightness is ensured, high accuracy is not required for the processing of the window hole, and the sealing work is unnecessary. As a result, assembly is simplified.

On the other hand, the tank inner part of the suction line is usually welded and fixed to the bottom of the tank in order to fix the strainer position, suppress vibrations, etc. During this welding, the height position of the strainer, the inclination seen from the front of the bent part It is necessary to perform positioning.

  In this case, if the configuration in which the tank inner portion is directly welded to the tank bottom surface is taken, the positioning is troublesome and the fixing operation of the tank inner portion becomes troublesome.

  On the other hand, according to the present invention, a rib is provided on the side surface of the bent portion so as to project outward, and the rib is welded to the bottom surface of the tank to fix the tank inner portion of the suction line in the tank. For this reason, the above positioning is facilitated, and the work for fixing the inner portion of the tank can be performed efficiently.

  In the present invention, it is preferable that the tank is installed on a beam-structured deck having a plurality of beams, and the concave portion is provided at a position avoiding the beams of the deck.

  As described above, in a construction machine such as an excavator, a deck having a beam structure is provided on an upper swing body on which a tank is mounted, and the tank is installed on the deck.

  In this case, by providing a recess at a position avoiding the deck beam, an extra structure such as a raised block is added on the deck to avoid interference with the recess, or the deck structure may be significantly changed. In addition, a necessary and sufficient volume can be secured in the recess.

  Further, in the present invention, it is desirable that the recess is formed by providing a window hole on the bottom surface of the tank and attaching a depth-like vessel-like cover in a state in which the window hole is closed from the outside. Item 3).

  The recess can also be formed by partially denting the tank bottom plate by pressing or the like.

However, if the recess is formed by providing a window hole on the bottom of the tank and closing it with a vessel-shaped cover as in the invention of claim 3, after the tank is assembled, the one end side portion of the inner portion of the tank is dropped into the hole. Since a method of attaching the cover later can be taken, the production of the entire tank including the piping inside the tank is simplified .

Further, in the present invention, the upper Symbol ribs, of providing a symmetrical arrangement on the left and right sides when viewed the bending portion from the front it is desirable (claim 4)
In this case, the adjustment of the inclination of the bent portion can be omitted or simplified, so that the fixing operation of the inner portion of the tank is further simplified and a stable fixing state can be obtained.

  According to the present invention, the strainer position can be lowered while suppressing the increase in size of the tank while adopting the in-tank piping system.

It is sectional drawing of the hydraulic-oil tank apparatus which concerns on embodiment of this invention. FIG. 2 is a partially enlarged view of FIG. 1. It is the III-III sectional view taken on the line of FIG. It is a perspective view of the portion in a tank of a strainer and a suction line in an embodiment. It is sectional drawing of the hydraulic-oil tank apparatus by the conventional tank piping system. It is sectional drawing of the hydraulic-oil tank apparatus by the conventional piping system in a tank.

  An embodiment of the present invention will be described with reference to FIGS.

  The embodiment is applied to a hydraulic oil tank device for an excavator.

  In the embodiment, the following points are the same as those of the conventional hydraulic oil tank apparatus that adopts the in-tank piping system shown in FIG.

  (i) A hydraulic oil tank (hereinafter simply referred to as a tank) 11 is formed in a rectangular parallelepiped box shape by a top plate, a bottom plate, and front, rear, left and right side plates.

  (ii) A deck 12 having a beam structure in which a plurality of beams 12 a are combined vertically and horizontally is provided on the upper revolving structure on which the tank 11 is mounted, and the hydraulic oil tank 11 is installed on the deck 12. Point.

  (iii) In the tank 11, a strainer 13 for filtering the working oil is installed at the bottom, and the working oil discharged from the strainer 13 is supplied to a suction side of a hydraulic pump (not shown) by a suction line 14.

  (iv) The suction line 14 is connected to the strainer 13 by an L-shaped bent portion (usually an elbow is used for pressure loss reduction) 15 at one end and is connected to the hydraulic pump at the other end.

  (v) A portion of the tank side of the suction line 14 including the bent portion 15 (a portion in the tank) 14a is disposed at the bottom of the tank, and one end of the suction line 14 is connected to the strainer 13 by the bent portion 15. The end side is derived from the tank side surface and connected to the tank outer portion 14b.

  In this hydraulic oil tank device, a rectangular window hole 16 that is long in the length direction of the tank inner portion 14a (the left-right direction in FIGS. 1 and 2) is provided at a position avoiding the beam 12a of the deck 12 in the bottom plate 11a of the tank 11. Is provided.

  The window hole 16 is the tank inner portion 14a, more specifically, the half of the entire length of the tank inner portion 14a on the strainer side including the bent portion 15 (hereinafter, this portion is referred to as the “dropping portion”, FIG. A container-like cover 17 having a depth and a width that is provided with a reference numeral “14a1” in FIG. 4 only is provided and is attached to the outer surface of the tank bottom plate 11a in a state of closing the window hole 16 from the outside.

  As a result, a concave portion 18 that is recessed downward is formed at the bottom of the tank, and the drop portion 14a1 of the tank inner portion 14a enters the concave portion 18 and sinks below the bottom surface of the tank.

  The depth of the concave portion 18 (cover 17) is arbitrarily set according to the desired sinking amount of the dropping portion 14a1 on the premise that the depth is smaller than the thickness of the deck 12.

  In the figure, the depth of almost the upper half of the drop portion 14a1 including the bent portion 15 is set to a depth that goes out of the recess 18 (substantially the lower half sinks), but the depth at which the sinking amount becomes larger than this. May be set.

  In order to make the cover 17 as compact as possible, it is desirable that the cover 17 has a shape along the radius of the drop portion 14a1 as shown in FIG.

  The cover 17 is attached by welding the peripheral edge to the tank bottom plate 11a. However, on the condition that oil tightness can be secured, the cover 17 is provided with a flange portion and bolted to the tank bottom plate 11a. You may take

  On the other hand, as means for fixing the tank inner portion 14a to the tank 11, the bent portion 15 is a portion that goes out of the recess 18 (positioned in the tank 11) and is seen on both the left and right side surfaces when viewed from the front. Vertical plate-like ribs 19 and 19 are provided so as to project outward, and the lower surfaces of the ribs 19 and 19 are fixed by welding to the inner surface of the bottom plate 11a.

  The ribs 19, 19 may be welded to the bent portion 15 as a separate member from the bent portion 15, or may be integrally formed with the bent portion 15.

  In addition, the ribs 19 and 19 are not limited to a triangular vertical plate shape, and may protrude into a square vertical plate shape, or may protrude into a square shaft shape or a round shaft shape.

  In this way, the tank inner portion 14a of the suction line 14 is disposed in the tank 11 in a state where the one end side portion (dropped portion) 14a1 including the bent portion 15 is dropped into the recess 18, so that the drop portion 14a1 is the tank. The height position of the strainer 13 in the tank 11 can be lowered by the amount of sinking from the bottom surface.

  In other words, while using the in-tank piping system, the height of the strainer 13, that is, the rise of the substantially lowest oil level in the tank 11 can be suppressed, and the increase in size of the tank 11 can be suppressed.

  In addition, since the recessed portion 18 is provided on the bottom surface of the tank and the dropped portion 14a1 is dropped into the recessed portion 18 in a state where oil tightness is ensured, the configuration is compared with the configuration in which the dropped portion 14a1 is dropped into the window hole 16 and the periphery is sealed. As a result, high accuracy is not required for the processing of the window hole 16, and the sealing work is unnecessary, so that assembly is simplified.

  In this case, since the concave portion 18 is provided at a position avoiding the beam 12a of the deck 12 of the beam structure, an extra structure such as a raised block is provided on the deck 12 in order to avoid interference with the concave portion 18 or the deck structure. A necessary and sufficient volume can be ensured in the recess 18 without significantly changing.

  Further, a window hole 16 is provided in the tank bottom plate 11a, and the recess 18 is formed by closing the window hole 16 with a vessel-shaped cover 17. Therefore, after the tank is assembled, the cover part 14a1 is dropped into the window hole 16 and covered. A method of retrofitting 17 can be taken.

  For this reason, manufacture of the whole tank including piping and fixation of the tank inner part 14a becomes easy.

  On the other hand, a vertical plate-like rib 19 is provided on the side surface of the bent portion 15 so as to project outward, and this rib 19 is fixed to the bottom surface of the tank 11 by welding to fix the tank inner portion 14a in the tank 11. In addition, it becomes easy to position the strainer 13 such as the height of the strainer 13 and the inclination of the bent portion 15 as viewed from the front, and the tank inner portion 14a can be fixed efficiently.

  In this case, since the ribs 19 are provided symmetrically on the left and right side surfaces when the bent portion 15 is viewed from the front, the adjustment of the inclination of the bent portion 15 can be omitted or simplified, so that the tank inner portion 14a can be fixed. The operation is further simplified and a stable fixed state can be obtained.

Other embodiments
(1) In the above embodiment, the recess 18 is formed by closing the window hole 16 from the outside with the cover 17, but the recess 18 may be formed as a part of the tank bottom plate 11a by pressing the tank bottom plate 11a.

  (2) The present invention is not limited to the case where an elbow is used as the bending portion 15 of the tank inner portion 14a, but can also be applied to the case where a bending pipe is used.

  (3) In the above-described embodiment, the hydraulic oil tank installed on the beam-structured deck 12 is illustrated. However, the present invention is a hydraulic oil tank that adopts an in-tank piping system, and the recess 18 does not get in the way. It can be widely applied to hydraulic oil tanks made in the state.

DESCRIPTION OF SYMBOLS 11 Hydraulic oil tank 11a Tank bottom plate 12 Deck 12a Beam 13 Strainer 14 Suction line 14a Tank inner part 14a1 Dropped part in tank inner part 14b Tank outer part 15 Bending part 16 Window hole 17 Cover 18 Recessed part 19 Rib

Claims (4)

A tank for storing hydraulic oil; a strainer provided at the bottom of the tank; and a suction line for supplying hydraulic oil from the strainer to the suction side of the hydraulic pump. In the hydraulic oil tank device in which the front end side of the tank inner portion is connected to the strainer via an L-shaped bent portion, a concave portion recessed downward is provided on the bottom surface of the tank, The tank inner portion of the suction line is disposed in a state where one end side portion including the bent portion is dropped into the concave portion , and a rib is provided outwardly projecting on the side surface of the bent portion. hydraulic oil tank system, characterized in that fixed to the tank the tank portion of the suction line by welding fixed to the bottom surface in the tank   2. The hydraulic oil tank apparatus according to claim 1, wherein the tank is installed on a deck having a beam structure including a plurality of beams, and the concave portion is provided at a position avoiding the beams of the deck.   3. The recess according to claim 1, wherein a window hole is provided in a bottom surface of the tank, and a concave cover is formed by attaching a depth-like cover in a state of closing the window hole from the outside. Hydraulic oil tank device. The hydraulic oil tank apparatus according to any one of claims 1 to 3, wherein the ribs are provided symmetrically on both left and right side surfaces when the bent portion is viewed from the front .

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