JPS5812922Y2 - Rear hoist cylinder circuit device for ditch digging machine - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rear hoist cylinder circuit device for a ditch excavator.

Conventionally, a pilot check valve a has been installed in the hoist cylinder circuit of waterway ditch excavators to prevent the working machine from falling naturally when it is self-propelled, but when it is desired to keep rear poise 1 to cylinder b in a floating state during excavation. Even if the operating valve C was moved to the floating position I, the rear hoist cylinder B was free to contract in the direction of contraction due to the pilot check valve a, but it was locked in the direction of extension and could not be moved.

The present invention was developed in view of the circumstances mentioned in 1-1 above, and its purpose is to make the rear hoist cylinder float during excavation without impairing the natural descent prevention of the work equipment during self-propelled operation. To provide a cylinder circuit device for a 2-chair 1 of a trench excavator for waterways that can perform the following functions.

The present invention will be explained below with reference to FIG.

In the drawing, 1 is an operating valve, and 2 is a rear hoist cylinder.

The drain port Mejf of the operation valve 1 is passed through the tank 11.

Pump ports i1a, lb of the operating valve 1 communicate with the discharge side of the pump.

One outlet port (IC) of the operating valve 1 communicates with the head side chamber 2a of the rear hoist cylinder 2 via a pipe line 3, and the other outlet port 1-1d of the operating valve 1 communicates with the head side chamber 2a of the rear hoist cylinder 2 via a pipe line 4. The rear hoist 1 communicates with the rod side chamber 2b of the cylinder 2.

The operation valve 1 has the other inlet ports I to 1b connected to one outlet port 1C and the other outlet port 1d connected to the drain port).
Extended position D and neutral position C, which communicate with each other, and the other pump port 1b with the other outlet port 1.
d, a retracted position E in which one outlet port 1C is connected to the drain port He, and both outlet ports IC,
A floating position B is provided which communicates the drain port 1e with the drain port 1e.

This conduit 4 is provided with a pilot check valve 5 that allows oil to flow only from the operating valve 1 side to the rod side chamber 2b.

In the drawing, 6 is a shuttle valve, and one inlet port (6a) and operating port (6b) of the shuttle valve 6 communicate with the outlet port 1C of the operation valve 1 via pipes 7 and 8. The other inlet port) 6C and the operating port 6d communicate with the drive circuit 12 of the wheel rotation hydraulic motor via pipes 9 and 10.

Further, the drain port 6e of the shuttle valve 6 communicates with the tank 11, and the outlet port 6f communicates with the operating port 5a of the pilot check valve 5 via a conduit 13.

The shuttle valve 6 has one artificial port (6a) and an outlet port (6a).
6f (first operating position F and exit port communicating with 6f)
A neutral position G in which the drain port 6C communicates with the drain port 6e and a second operating position A in which the other inlet port 6C communicates with the outlet port 6f are provided.

Since the wheel is rotating during excavation, oil from the drive circuit enters the input port 6C1 of the shuttle valve 6 and the operating port 6d, and the second operating position of the shuttle valve 6 is located on the port side, causing oil to flow through the pipe. It enters the operating port 5a of the pilot check valve 5 through the pilot check valve 5.
open.

For this purpose, a taker hoist cylinder 2 is operated to float on the operating valve 1 and the floating position B is positioned on the port side.
can be made to float.

Further, when the hoist cylinder is self-propelled, the neutral position C of the operating valve 1 is positioned on the port side, and the hoist cylinder is completely locked.

Furthermore, when the extension position D of the operating valve 1 is located on the port side to control the rear hoist cylinder 2, the head pressure of the rear hoist cylinder 2 acts on the shuttle valve 6 and the pilot check valve 5 opens.

As detailed above, the present invention has pump ports 1a, lb.
is connected to the discharge side of the pump, drain ports 1-16 and 1f are connected to the tank 11, and one outlet port 1C of the operating valve 1 is connected to the head side chamber 2a of the rear hoist cylinder 2 via the pipe 3. The other outlet port 1d of 1 is connected to the rod side chamber 2b of the rear hoist cylinder 2 via a pipe 4, and this pipe 4 is provided with a pilot check valve 5 that allows oil to flow only from the operating valve 1 side to the rod side chamber 2b. , the other inlet port 1b is connected to one outlet port 1C, the other outlet port 1d is connected to the drain port (drain port) le, and the other pump port 1b is connected to the other outlet port Hd. A retracted position E in which one outlet port 1C is communicated with the drain port 1e, and a floating position B in which both outlet ports IC and ld are communicated with the drain port 1e are provided. One inlet port 6a of the shuttle valve 6 and the operating port 6 via channels 7, 8.
b, and the drive circuit 12 of the hydraulic motor for wheel rotation.
The other inlet port () 6C and the operating port (6d) of the shuttle valve 6 are connected to the valve via pipes 9 and 10, and the outlet port (6f) of the shuttle valve 6 is connected to the pilot check valve 5 via a pipe 13 to operate the pilot check valve 5. port) 5a and the shuttle valve 6.
A neutral position in which the drain port 6e of the shuttle valve 6 is communicated with the tank 11, and the outlet port 6f of the shuttle valve 6 is communicated with the drain port 6e. The gist of this invention is to provide a rear hoist cylinder circuit device for a ditch excavator, characterized in that it is provided with a second operating position A that communicates the other inlet port (6C) with the outlet port (6f).

Therefore, during excavation, oil from the drive circuit 12 acts on the operating port 6d of the other input port 6C1 of the shuttle valve 6, and the second operating position A is located on the port side, and the oil flows into the operating port 5a of the pilot check valve 5. and opens the pilot check valve 5.

For this reason, by locating the floating position B in the operating valve 1 on the port side, the rear hoist cylinder can operate in both the retracting and extending directions, and the rear hoist cylinder can be operated in both the retracting and extending directions, allowing the rear hoist to be used during excavation without compromising the ability to prevent the work equipment from falling naturally when it is self-propelled. The cylinder can be placed in a floating state.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the configuration of a conventional rear hoist shinonda circuit device for a trench excavator for waterways, and FIG. 2 is an explanatory diagram of the configuration of an embodiment of the present invention. 1 is an operating valve, 2 is a rear hoist cylinder, 5 is a pilot check valve, and 6 is a shuttle valve.

Claims (1)

[Scope of utility model registration request] Pump port)-13, lb is connected to the discharge side of the pump, drain ports le and If are connected to the tank 11, and one outlet port HC of the operation valve 1 is connected to the rear hoist I and the head side chamber 2a of the cylinder 2 via the pipe line 3. The other outlet port 1d of the operating valve 1 is connected to the rod side chamber 2b of the rear hoist cylinder 2 via a pipe 4, and the pipe 4
A pilot check valve 5 that allows oil to flow only from the operating valve 1 side to the rod side chamber 2b is installed in the operating valve 1, and the other person [-1
Port 1b is connected to one outlet port 1C and the other outlet port 1 to 1d are connected to drain port 1e, respectively, at an extended position D, a neutral position C, and the other pump port Hb.
A retracted position E in which one outlet port 1c is communicated with the drain port 1e and a floating position B in which both outlet ports 1C91d are communicated with the drain port 1e are provided. The outlet port 1c is connected to one input port 6a and the operating port 1-6b of the shuttle valve 6 via conduits 7 and 8, and the other port of the shuttle valve 6 is connected to the drive circuit 12 of the wheel rotation hydraulic motor. The inlet port 6C and the operating ports 1-6d are connected via pipes 9 and 10, and the outlet port 6f of the shuttle valve 6 is connected to the operating port 5a of the pilot check valve 5 via the pipe 13. Shuttle valve 6 drain
The shuttle valve 6 is connected to the tank 11.
The first operating position F communicates the inlet port 6a with the outlet port -6f, the neutral position G communicates the outlet L port 6f with the drain port 1-66, and the outlet port 6C 1-6 A rear hoist 1 to cylinder circuit device for a ditch excavator, characterized in that a second operating position A communicating with f is provided.