JPH0635358U - Pressure oil supply device - Google Patents

Abstract

(57) [Summary] [Purpose] One pilot valve can be used to switch between the blade switching valve and the boom switching valve. [Structure] Pilot valve 3 operated by operating lever 34
The output side of 1 is selectively connected by a switching valve 30 to one of the pilot pipes 21 and 22 of the blade switching valve 7 and one of the pilot pipes 25 and 26 of the boom switching valve 10. A switch 35 for energizing the solenoid 33 is provided on the operation lever 34 to turn on the switch 35.
When it is turned off, the switching valve 30 is switched so that one of the blade switching valve 7 and the boom switching valve 10 can be switched.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a pressure oil supply device that supplies pressure oil to a plurality of actuators in a small power shovel or the like.

[0002]

[Prior art]

 Small excavators are equipped with blades outside the boom, arm and bucket, and are equipped with blade cylinders as extra actuators outside the standard power shovel actuators such as boom cylinders, arm cylinders and bucket cylinders.

A device shown in FIG. 1 is known as a device for supplying pressure oil to each actuator of the aforementioned small power shovel. That is, the swing switching valve 3, the swing switching valve 4, the arm switching valve 5, the left traveling switching valve 6, the blade switching valve 7, the right traveling switching valve 8, the bucket switching valve 3 in the discharge passage 2 of the hydraulic pump 1. A switching valve 9 and a boom switching valve 10 are provided, and by switching each switching valve, a swing cylinder 11, a swing motor 12, an arm cylinder 13, a left traveling motor 14, a blade cylinder 15, a right traveling motor 16, a bucket cylinder 17, Pressure oil is supplied to the boom cylinder 18.

[0004]

[Problems to be solved by the device]

 As described above, when a plurality of switching valves are provided, the number of operating levers for switching the switching valves increases, and the number of rods connecting the operating levers and the switching valves and the pilot piping increase, which not only increases the space. Or the cost will be higher. For example, as shown in FIG. 1, the output side of the pilot valve 20 which can be switched by the blade operating lever 19 is connected to the blade switching valve 7 by the pilot pipes 21 and 22, and the pilot valve which can be switched by the boom operating lever 23. The output side of 24 is connected to the boom switching 10 by pilot pipes 25 and 26. This requires multiple control levers, multiple pilot valves, and long pilot piping.

Therefore, an object of the present invention is to provide a pressure oil supply device capable of solving the above problems.

[0006]

[Means for Solving the Problems]

 The hydraulic fluid discharged from the hydraulic pump 1 is supplied to a plurality of actuators by a plurality of switching valves, and the pilot pipes of the two switching valves of the plurality of switching valves and the output side of one pilot valve 31 are connected by a switching valve 30. Pressure oil supply device.

[0007]

[Work]

 By switching the switching valve 30, the output pressure oil of one pilot valve 31 can be selectively supplied to one of the two switching valves to switch the switching valve.

[0008]

【Example】

 An embodiment of the present invention will be described with reference to FIG. The same members as those of the conventional one have the same reference numerals. The pilot pipes 21 and 22 of the blade switching valve 7 and the pilot pipes 25 and 26 of the boom switching valve 10 are connected and controlled by the switching valve 30 to the output side of the pilot valve 31. The switching valve 30 is a solenoid valve that is held at a first position A by a spring 32 and is switched to a second position B by energizing a solenoid 33. A switch 35 is provided on an operation lever 34 of a pilot valve 31. By pressing the switch 35, the solenoid 33 is energized.

Therefore, when the operation lever 34 is operated without pressing the switch 35, the switching valve 30 is set to the first position A and the boom switching valve 10 is switched, and the switch 35 is pressed to operate the operating lever 34. When is operated, the switching valve 30 is set to the second position B, and the blade switching valve 7 is switched.

[0010]

[Effect of device]

 By switching the switching valve 30, the output pressure oil of one pilot valve 31 can be selectively supplied to one of the two switching valves to switch the switching valve. Therefore, the number of pilot valves 31 and operating levers 34 can be made smaller than the number of actuators, so that the cost can be reduced, and the length of the pilot piping up to the switching valve 30 can be simplified and the space can be reduced. .

[Brief description of drawings]

FIG. 1 is a conventional hydraulic circuit diagram.

FIG. 2 is a hydraulic circuit diagram showing an embodiment of the present invention.

[Explanation of symbols]

1 ... Hydraulic pump, 2 ... Discharge passage, 7 ... Blade switching valve,
10 ... Boom switching valve, 21 ... Pilot piping, 22
… Pilot piping, 25… Pilot piping, 26…
Pilot piping, 30 ... switching valve, 31 ... pilot valve, 33 ... solenoid, 34 ... operating lever, 35 ... switch.

Claims (2)

[Scope of utility model registration request] Claim: What is claimed is: 1. Discharge pressure oil of the hydraulic pump 1 is supplied to a plurality of actuators by a plurality of switching valves, and pilot pipes of two switching valves in the plurality of switching valves and an output side of one pilot valve 31 are switched. A pressure oil supply device characterized by being connected at 30. 2. The solenoid valve for switching the switching valve 30 from the first position to the second position by energizing the solenoid 33, and the operating lever 34 of the pilot valve 31 is provided with a switch 35 for energizing the solenoid 33. Item 1. The pressure oil supply device according to item 1.