JP3280603B2 - Hydraulic control device for construction machinery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a hydraulic control device for a construction machine such as a hydraulic shovel.

[0002]

2. Description of the Related Art In general, a construction machine such as a hydraulic shovel is provided with a plurality of hydraulic actuators and works by appropriately combining these hydraulic actuators. These valves are centrally mounted in one valve box and mounted on the fuselage. By the way, in such a construction machine, for example, when this is a hydraulic excavator, a dozer operation using a dozer blade may be performed separately from a bucket operation, and in order to cope with such a case, the valve box includes a dozer. It is essential to provide a valve for raising and lowering the blade and a spool operating means for operating the spool of the valve, and these are usually provided as standard.

[0003]

Among the dozer blades as such an attachment, there is a special specification having a so-called tilt function for raising and lowering one of the right and left, and this specification is optionally provided by a user or the like. It is generally done. By the way, in order to correspond to various attachments such as a hydraulic breaker, a crusher, and a pile punching machine, the valve box is generally provided with a spare valve for taking out an external hydraulic pressure. Next, this spare valve will be used. By the way, the spool of the spare valve is generally not provided with a spool operating means because it is necessary to perform a spool operation required as an attachment work, and a user who does not need such optional work is also required. For such a user, it is not preferable to provide all unnecessary spool operating means as standard equipment because of an increase in cost. As a result, for example, in order to provide a tilt specification, a spool operating means for tilt (corresponding to the auxiliary spool operating means of the present invention) must be provided on the spool of the spare valve. Since it was arranged at a position away from the valve box and connected to the valve spool via a connecting means consisting of a long rod, etc., the connecting means would be loose and the valve box would not be generally subject to body vibration. The auxiliary spool actuating means receives different vibrations without such considerations, while being mounted via anti-vibration material, so smooth spool operation is impaired and the accuracy of the optional hydraulic actuator However, there is a problem that high control is difficult, and there is a problem to be solved by the present invention.

[0004]

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention has been made to solve these problems, and is intended to control the supply of hydraulic oil from a hydraulic pump to a plurality of hydraulic actuators. A valve box in which each valve for operating each valve is provided in a concentrated manner, and a spool operating means for operating each valve spool is disposed on one side of the valve box so as to face each other, and a hydraulic hose connected to the valve box is provided. In a construction machine which is piped so as to pass above the spool operating means, when arranging auxiliary spool operating means for operating a spool of an optional valve provided in the valve box, The means is disposed between the spool operating means and the hydraulic hose. By doing so, the spool operating means can be arranged close to the spool of the optional valve, and the spool can be operated without play. In this case, the present invention may be such that the auxiliary spool operating means is attached via a bracket to a valve base for mounting the valve box to the body frame, whereby the auxiliary spool operating means is vibrated together with the valve box. Can be in a state. Further, in the present invention, the auxiliary spool operating means includes a solenoid and a hydraulic cylinder means switched by the operation of the solenoid, and one of the cylinder rods of the hydraulic cylinder means on which the cylinder rod projects. The end face can be sealed with a bracket in between, so that the bracket can also be used as a closing member for the cylinder, and the number of parts can be reduced.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to FIGS. In the drawings, reference numeral 1 denotes a canopy-type hydraulic excavator, which is a crawler-type lower traveling body 2, an upper revolving body 3 that is rotatably supported above the lower traveling body 2, and an upper revolving body. The bucket 3 comprises a bucket working unit 4 and the like connected to the front end of the body 3. Each of the work such as traveling of the lower traveling body 2, swinging of the upper swing body 3, and bucket work of the bucket working unit 4 is performed by upper swinging. The basic configuration such as that of receiving the pressurized oil from a hydraulic pump P driven by the power of an engine (not shown) mounted on the body 3 is the same as the conventional configuration.

Reference numeral 5 denotes a valve box in which a plurality of valves are assembled and assembled in a line. The valve box 5 has a valve base 6 fixed to the lower surface thereof with a rubber damper 6a interposed therebetween. Multiple valve spools 7
a is fixed to the main frame 3a of the upper traveling body 3 in a posture protruding inward in the left-right direction of the body. In the valve box 5, for example, a valve group 7A for controlling supply of pressurized oil to the bucket working unit 4 and a valve group 7B for controlling supply of pressurized oil to the swing joint 8 and the swing motor 9 are formed. However, in the present embodiment,
A spare valve 10 for taking out an external hydraulic pressure is assembled so as to be sandwiched between the two valve groups 7A and 7B, and the spare valve 10 is attached to a dozer blade B (not shown) for tilting which is optionally mounted in the present embodiment. It is used as a control valve to control the supply of pressure oil to the cylinder. In the figure, reference numeral 11 denotes a turning circle.

Reference numeral 12 denotes a bracket 12a on the valve base 6.
A link shaft supported through the link shaft 12
One link arm 12c protruding from a link boss 12b rotatably supported on the other is connected to each corresponding valve spool 7a of the valve box 5 via a connecting rod 12d, while the other protruding from the link boss 12b. The link arm 12e is connected to an operating mechanism (not shown), and the necessary operation of the valve 7 is performed by pushing and pulling the valve spool 7a by swinging the link boss 12b based on operation of an operation lever or the like. This constitutes a spool operating means. And the link boss 12b
The upper surface is fixed to the valve base 6 such that the upper surface is located lower than the upper surface of the valve box 5 and inside the inner edge of the valve base 6. On the other hand, an L-shaped elbow 13 is connected to the upper surface of each valve of each of the valve groups 7A and 7B so as to protrude upward, and is connected to corresponding hydraulic actuators through a pipe 13a connected to the tip of the elbow 13. The supply of pressurized oil is performed.
Most of them are piped above the link boss 12b with a gap S.

Further, one side 14a of an L-shaped mounting bracket 14 is screwed to the inner edge of the valve base 6 at a position facing the spare valve 10, and the other side (standing piece) 14b is connected to the valve. It is set to stand up at a substantially inner edge position of the base 6 so as to face the spool 10a of the preliminary valve 10. An auxiliary spool operating means 15 for operating the spare valve spool 10a is attached to the bracket rising side 14b.
The auxiliary spool actuating means 15 in the present embodiment has a vertical height that fits in the gap S between the link boss 12b and the pipe 13a. Spool 1
0a, and can be directly operated without a long link or the like between the spool 10a.

The auxiliary spool operating means 15 is unitized by a hydraulic cylinder 16 for operation and an electromagnetic switching valve 17 disposed on the upper surface of the hydraulic cylinder 16 for operation. Is constituted by using a cylinder tube 16a attached to the bracket rising side 14b and a cylinder rod 16b moving inside the cylinder tube 16a. The cylinder cylinder 16a is open at one end where the cylinder rod 16b projects,
The opening end thereof is fixed with bolts 16c in a state where it abuts against the bracket rising side 14b, whereby the auxiliary spool operating means 15 is mounted on the mounting bracket 14. In addition, 16d is packing, 1
6e and 16f are O-rings for sealing the open ends. Further, the tip end of the cylinder rod 16b protruding from the opening end of the cylinder cylinder 16a penetrates through a through hole 14c formed in the bracket standing side 14b so as to be freely movable, and protrudes toward the valve box 5 side.
The tip of this cylinder rod 16b is an auxiliary link 16g.
And is operatively connected to the spare valve spool 10a via The auxiliary spool actuating means 15 is configured such that, by switching the electromagnetic switching valve 17, the valve is switched from a neutral state to a state in which the cylinder rod 16b protrudes toward the spare valve spool 10a and to a retracted state. I have. Incidentally, reference numeral 16h denotes a return spring for returning the cylinder rod 16b to the neutral position, and reference numeral 16i denotes a spacer. Further, the auxiliary spool operating means 15 is set to operate based on a lever operation of an operation lever 15a provided on an operation section of the upper swing body 3.

[0010] In the embodiment of the present invention configured as described above, when the dozer operation is performed using the dozer blade B, the dozer blade B is connected to one of the valve groups 7A provided in the bubble box 5 in advance. When the dozer blade B with a tilt function (specification) is selected, the spare valve 10 is used for tilting operation. The auxiliary spool operating means 15 for tilting is linked to the valve spool 10a, and the auxiliary spool operating means 15 is operated by operating the operation lever 15a. In this case, the auxiliary spool operating means 15 is attached to the valve base 6 via the bracket 7, and the auxiliary spool operating means 15 is connected to the link boss 12 b provided in a state of being opposed to the inner edge of the valve base 6. The gap S formed between the pipe 13a and the dead space, which has been a dead space in the past, can be effectively used as a storage space and can be accommodated therein, and there is no need to separately secure a space for mounting the auxiliary spool operating means 15. Further, the auxiliary spool operating means 15 can be arranged in a state of being close to the auxiliary valve spool 10. The distal end of the cylinder rod 16b is connected to the auxiliary link 16 which is short between the auxiliary valve spool 10a and the auxiliary valve spool 10a.
g, the spare valve spool 10a can be actuated to prevent backlash as in the conventional case where the spare valve spool is connected to the spare valve spool via a long connecting means such as a long rod. it can.

Further, the auxiliary spool operating means 15 is fixed together with the valve box 5 on the valve base 6 provided via the damper 6a in order to avoid vibration from the body frame 3a. Means 1
The vibration of the spool 5 together with the valve box 5 is the same even if it vibrates. Therefore, a smooth spool operation can be realized, and the tilt operation can be controlled accurately.

In addition, since the opening end of the operating cylinder 16 is closed by the bracket rising side 14b, a dedicated closing member is not required, so that the number of parts can be reduced, the number of parts can be shared, and the dedicated cylinder can be used. Because of the absence of the closing member, the weight and size can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view of a hydraulic shovel.

FIG. 2 is a plan view of a valve box portion.

FIG. 3 is a plan view of a main part.

FIG. 4 is a side view of a main part.

FIG. 5 is a side view of the auxiliary spool operating means.

FIG. 6 is a sectional view taken along line XX in FIG. 5;

FIG. 7 is a hydraulic circuit diagram of a main part.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hydraulic excavator 3 Upper revolving unit 4 Bucket work part 5 Valve box 6 Valve base 6a Rubber damper 7A Valve group 7a Valve spool 10 Spare valve 10a Spool 12b Link boss 13a Piping 14 Mounting bracket 15 Auxiliary spool operating means 16 Hydraulic cylinder for operation 16b cylinder Rod 16g Auxiliary link 17 Solenoid

Claims (3)

(57) [Claims] 1. A valve box in which valves for controlling the supply of pressure oil from a hydraulic pump to a plurality of hydraulic actuators are provided in a centralized manner.
In a construction machine in which spool operating means for operating each valve spool are disposed to face each other, and a hydraulic hose connected to the valve box is piped so as to pass above the spool operating means, In arranging auxiliary spool operating means for operating a spool of an optional valve to be equipped, the auxiliary spool operating means is a hydraulic control device for a construction machine arranged between the spool operating means and a hydraulic hose. 2. The hydraulic control device for a construction machine according to claim 1, wherein the auxiliary spool operating means is mounted via a bracket to a valve base for mounting the valve box to the body frame. 3. The auxiliary spool actuating means according to claim 2, wherein the auxiliary spool actuating means comprises a solenoid and hydraulic cylinder means switched by the operation of the solenoid, and is provided on a side on which a cylinder rod of a cylinder constituting the hydraulic cylinder means projects. A hydraulic control device for a construction machine in which one end surface is sealed via a bracket.