KR20180082103A - Working machine lifting and working fluid take out hydraulic device of agricultural work vehicle - Google Patents

Abstract

Disclosed is a hydraulic apparatus for lifting and lowering a working machine of a working vehicle for agricultural use. The hydraulic apparatus according to the present invention includes an elevating control valve unit for controlling the supply of pressure oil for elevating driving to a three-point elevating device mounted on the rear end of the agricultural working vehicle and driven by hydraulic pressure, a hydraulic pressure take-off valve unit provided to be able to receive pressurized oil in preference to the lift control valve unit on the basis of the flow of pressurized oil while interrupting the extraction of the pressurized oil out of the working vehicle for driving an external working machine driven by hydraulic pressure, and a flow control valve unit provided between the hydraulic pressure takeoff valve unit and the elevation control valve unit with a bypass flow path for fluidly connecting the hydraulic pressure supply valve unit supply side pressure line and the lift control valve unit supply side pressure line formed therein and a flow control valve provided so as to control the opening amount of the input-side branch portion of the bypass flow path, wherein the flow rate of the bypass flow path is regulated through the flow rate regulator to regulate the amount of flow that is bypassed to the pressure line on the supply side of the elevating control valve unit via the bypass flow path, and thus the external hydraulic pressure can be simultaneously discharged.

Description

TECHNICAL FIELD [0001] The present invention relates to a hydraulic device for lifting and lowering a working machine of a working vehicle for agricultural use,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a hydraulic device for lifting and lowering a working machine for an agricultural work vehicle, and more particularly, to a hydraulic device for lifting and lowering an outer working machine through a three- To a hydraulic device for lifting and lowering a working machine of a working vehicle and extracting the hydraulic pressure.

 The work vehicle called 'tractor' has a structure and characteristics which are advantageous for carrying out various work by attaching an external working machine to a hitch (hereinafter referred to as 'three-point lifting device') of the rear of the vehicle. For example, work machines such as rake, rotavator, plow, and harrow are attached to the hitch to perform various farming operations such as tilling, crushing, pest control, pumping, and threshing .

The three-point lift device is a lift cylinder constituting a three-point elevation device in accordance with flow control of a working fluid (hereinafter referred to as "pressure oil") of a lift control valve operated by a signal outputted by a controller in accordance with a lever operation of a tractor- And the height of the external working machine with respect to the ground can be adjusted.

The tractor rear is provided with a hydraulic pressure take-off valve unit for extracting the pressurized oil in the tractor from the tractor to supply the pressurized oil to the work machine as a power source for operating the external working machine. The actuator on the machine side is connected to the output port by a hydraulic hose, so that the compressor on the tractor main unit is driven.

The hydraulic pressure supply valve 100 applied to the tractor is a directional control valve for regulating the flow of pressurized oil by switching an internal flow path by an external operation force. As shown in Fig. 1, a plurality of directional control valves 110a to 110c And is configured to be connected to each other so as to be fluid-flowable, and can receive pressurized oil prior to the elevation control valve 200 based on the flow of the pressurized oil.

More specifically, in the conventional hydraulic circuit take-off and external circuit elevator circuit configuration, as shown in Fig. 1, the hydraulic take-out valve 100 gives priority to the lift control valve 200 on the basis of the flow of the pressurized oil In order to be supplied, the two valves 100 and 200 are configured to form a series circuit in a circuit. Therefore, conventionally, the pressure oil can only be used sequentially.

That is, since the pressure oil passing through the plurality of directional control valves 110a to 110c is supplied to the elevation control valve 200 as a ratio, even if only one of the plurality of directional control valves is used, (300) is not operated, so that it is not possible to simultaneously carry out two operations (lifting and lowering of the working machine and extraction of the external hydraulic pressure). For this reason, conventionally, there is a problem that the efficiency of the work is low and the working time is long.

Japanese Patent Application Laid-Open No. 2008-061552 (Published March 21, 2008)

SUMMARY OF THE INVENTION It is an object of the present invention to provide a hydraulic apparatus for lifting and lowering a working machine for an agricultural work vehicle capable of simultaneously raising and lowering an external working machine through a three-point lift device and extracting an external hydraulic pressure through a hydraulic take-

According to an embodiment of the present invention as a solution to the problem,

A device mounted on the rear of the agricultural work vehicle and capable of simultaneously performing the elevating operation and the driving operation of the external working machine using hydraulic pressure,

An elevating control valve unit which is mounted on the rear end of the agricultural working vehicle and controls the supply of pressure oil for elevating driving to a three-point elevating device driven by hydraulic pressure;

And a control unit that is connected to the three-point elevation device and interrupts the extraction of the pressure oil outside the working vehicle for driving the external working machine driven by the hydraulic pressure, and supplies the pressure oil to the elevation control valve unit, A hydraulic takeoff valve unit; And

Wherein a bypass flow path is formed between the hydraulic pressure takeoff valve unit and the ascending / descending control valve unit for fluidly connecting the hydraulic pressure takeoff valve unit supply pressure line and the lift control valve unit supply pressure line in fluid communication therewith, And a flow control valve unit provided with a flow control valve for controlling the opening amount of the flow path formed by the supply valve unit supply side pressure line,

The flow rate of the bypass flow path through the flow control valve is regulated to be bypassed to the pressure line on the supply control valve unit side via the bypass flow path, The present invention also provides a hydraulic apparatus for lifting and lowering a working machine for an agricultural working vehicle in which external hydraulic pressure is taken out through a hydraulic circuit.

The hydraulic pressure takeoff valve unit according to the embodiment of the present invention includes a valve unit having a structure in which a plurality of directional control valves are arranged in a stacked manner on the lower side so that an internal spool is moved by an operation signal input from the outside, And a valve cover coupled to an upper portion of the directional control valve at the uppermost one of the directional control valves and having an internal flow path connected to the flow path of the uppermost directional control valve.

Further, in the embodiment of the present invention, the flow control valve unit may be coupled to the lower-most direction control valve among the direction control valves arranged in layers so as to make fluid-flowable connection with the lowermost control valve.

According to the embodiment of the present invention, the flow rate of the hydraulic pressure generated by the hydraulic pressure take-off valve unit, which forms the bypass flow passage for fluidly connecting the hydraulic pressure supply valve unit supply side pressure line and the lift control valve unit supply side pressure line, As the control valve unit is disposed, the operation of the three-point elevating device and the extraction of the external hydraulic pressure through the hydraulic take-out valve can be simultaneously realized with a simple additional configuration.

That is, the lifting operation of the external working machine and the predetermined operation using the external working machine can be performed at the same time, so that the continuity and efficiency of the work can be improved and the working time can be greatly shortened. Since the flow control valve is constructed as a single module, it is possible to exclude the cost loss and the space required when the flow control valve is separately constructed.

1 is a hydraulic circuit diagram for external hydraulic pressure take-off and external work machine elevation applied to a conventional agricultural work vehicle.
BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a hydraulic system for an agricultural machine,
Fig. 3 is an enlarged view of the hydraulic device for lifting and lowering the work machine of Fig. 2; Fig.
4 is a hydraulic circuit diagram of a hydraulic device for lifting and lowering a work machine and taking out hydraulic pressure according to an embodiment of the present invention.
5 and 6 are operational states showing the flow of pressure oil (working fluid) in accordance with the valve switching state of the hydraulic pressure supply valve unit.

Hereinafter, preferred embodiments of the present invention will be described in detail.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. It is to be understood that the terms "comprises", "having", and the like in the specification are intended to specify the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, or combinations thereof.

Also, the terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

In addition, the terms " part, "" unit," " module, "and the like, which are described in the specification, refer to a unit for processing at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software .

In the following description with reference to the accompanying drawings, the same reference numerals are given to the same constituent elements, and a duplicate description thereof will be omitted. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

FIG. 2 is a perspective view showing a rear portion of an agricultural work vehicle to which a hydraulic device for lifting and lowering a worker is applied according to an embodiment of the present invention. FIG. 3 is an enlarged view of a hydraulic device for lifting and lowering a worker FIG. And Fig. 4 is a hydraulic circuit diagram of a hydraulic device for lifting and lowering a work machine and taking out hydraulic pressure according to an embodiment of the present invention.

2 to 4, a hydraulic device for lifting and lowering a work machine according to the present invention can simultaneously perform a lifting operation and an operating machine driving operation of an external working machine using hydraulic pressure, And a flow control valve unit 10 for regulating the flow rate of the pressure oil supplied to the valve unit 30 and the hydraulic pressure takeoff valve unit 20 and between the valve units 20 and 30, respectively.

The lift control valve unit 30 may be attached to the upper surface or the side surface of the lift unit cover at the rear upper end of the mission case, though not specifically shown. The elevation control valve unit 30 is connected to the three-point elevation device 40 mounted on the rear of the agricultural work vehicle and driven by hydraulic pressure to intermittently supply pressurized oil for the elevation drive. The hydraulic pressure supply valve unit 20, On the downstream side in the circuit.

The lift control valve unit 30 is largely constituted by the ascending and descending main spools 34 and 38, the ascending and descending proportional solenoids 32 and 36 and the unloading valve 31 as shown in the circuit diagram of Fig. When the driver moves the lift control lever with the electric angle sensor, the ascending or descending proportional solenoid 32 or 36 is operated correspondingly, and the ascending or descending main spool 34 or 38 is opened or closed so that the lifting cylinder is retracted and driven The elevating arms 42R and 42L of the three-point elevating device 40 are driven to move up and down.

The flow rate supplied from the hydraulic pressure take-off valve unit 20 side flows into the P port of the circuit diagram, but since the proportional solenoids 32 and 36 for ascending and descending are closed, the front end pressure of the unloading valve 31 is increased The pilot line PL1 at the inlet of the unloading valve 31 is transmitted to the lower portion of the spool to open the spool of the unloading valve 31 and eventually the flow rate supplied to the P port is discharged through the unloading valve 31 .

The pressure oil flowing into the P port is transmitted to the ascending main spool 34 through the pilot line PL2 as the ascending proportional solenoid 32 is opened so that the ascending main spool 34 Is opened. Accordingly, the pressurized oil supplied through the P port is uniformly supplied to the pair of left and right lifting cylinders 41R and 41L to raise the three-point lifting device 40. As a result, the external lifting device connected to the three- .

At this time, the unloading valve 31 is kept in the closed state by the hydraulic pressure transmitted through the pilot line PL3 located between the rising main spool 34 and the check valve 39 so that the drain through the unloading valve 31 is completely shut off The upward proportional solenoid 32 is automatically closed and the lifting arms 42L and 42R are closed when the three-point lifting device 40 reaches the position desired by the driver. The driver stops at the desired position.

The descent of the ascending / descending arm is realized by the driver operating the descending operation lever downward than the current position. Specifically, the downward proportional solenoid 36 is opened and the hydraulic pressure of the P port is transmitted to the downward main spool 38 through the pilot line PL4 when the up / down operation lever disposed on the driver's seat is operated downward from the current position, The spool 38 is moved to the open position.

Accordingly, the fluid filled in the lifting cylinders 41L and 41R is discharged to the R port through the descending main spool 38 and the descending proportional solenoid 36, thereby lowering the lifting arms 42L and 42R. Here, the descending drain line is formed not only by the descending main spool 38 but also through the descending proportional solenoid 36, so that the descending speed can be increased as needed.

On the other hand, the descending main spool 38, the descending proportional solenoid 36 and the unloading valve 31 are connected to each other through the pilot line PL5. Accordingly, when the P port pressure is transmitted to the unloading valve 31 when it is transmitted to the descending main spool 38 through the descending proportional solenoid 36, the unloading valve 31 is repeatedly opened and closed at the time of descent.

That is, when the pressure of the P line is discharged through the unloading valve 31 at the time of lowering the lift arm, the unload valve 31 is properly opened and closed according to the magnitude of the pressure. Accordingly, A pressure that is easy to maintain the spool 38 in the open position can be formed in the P line.

The hydraulic pressure take-off valve unit 20 uses hydraulic pressure and interrupts the extraction of the pressure oil outside the working vehicle for driving the external working machine connected to the three-point elevating device 40. [ 2 and 3, the hydraulic pressure take-off valve unit 20 can be mounted on the upper surface of the lift unit cover 43. The hydraulic pressure take-out valve unit 20 can be mounted on the lift control valve unit 30) upstream of the lift control valve unit (30).

Specifically, the hydraulic pressure take-out valve unit 20 includes a plurality of, preferably three, directional control valves 20a to 20c, in which the internal spool is moved by a physical operation signal input from the outside, And a valve cover having an inner flow path 250 connected to a flow path of the upper-most directional control valve 20c and coupled to an upper portion of the directional control valve 20c, 20d.

One of the plurality of directional control valves 20a to 20c may be a detent double acting valve capable of fixing the internal spool to a desired operating position by a detent ball when operating the internal spool through an operation lever, Since the spool can be fixed to a desired operating position by the detent ball, continuous supply of hydraulic pressure to the external working machine is possible. For example, it can be used in a work machine equipped with a hydraulic motor or the like.

4, the directional control valves 20a to 20c of the laminated structure constituting the hydraulic pressure takeoff valve unit 20 are arranged such that the pressurized oil supplied through the P port of the flow control valve unit 10 is passed through, (The A port and the B port of each control valve), and the actuator of the working machine, which uses the hydraulic pressure at the output port of the desired directional control valves 20a through 20c, is connected to the hydraulic hoses Connect and use.

That is, the hydraulic pressure take-out valve unit 20 according to the present invention includes a plurality of directional control valves 20a to 20c arranged in a stacked manner in a downward direction, and the adjacent directional control valves 20a to 20c have the same function (A port and B port) connected to each other through a hydraulic hose and an actuator on the outside of the working machine, respectively.

Each of the directional control valves 20a to 20c may be a manual type that is configured to move the spool in the axial direction by the operation lever to regulate the flow of the hydraulic fluid, It may be a solenoid type that is switched by an external electrical signal, or it may be a 6 port 3 way valve composed of an input port, a discharge port, a neutral port, and two output ports.

Accordingly, each of the directional control valves 20a to 20c is provided with a switch and a valve (not shown) for extending the actuator of the external working machine, for example, the hydraulic cylinder according to the position of the internal spool according to the input of the operation force So that the pressure can be supplied to the elevating control valve unit 30 as it is through the neutral line formed in the three-way valve.

For example, when one of the directional control valves 20a to 20c is switched to the extension side of the actuator 60, the hydraulic fluid supplied through the oil supply line 21 is supplied to the extension side of the actuator 60 under the control of the directional control valve The hydraulic fluid in the opposite hydraulic chamber is drained to the oil tank T via the corresponding directional control valve and the oil drain line 24 when the actuator 60 is extended.

On the contrary, when one of the directional control valves 20a to 20c is switched to the contraction side of the actuator 60, the hydraulic fluid supplied through the oil supply line 21 is supplied to the hydraulic chamber in the shrinkage direction of the actuator 60, And the hydraulic oil in the opposite hydraulic chamber is drained to the oil tank T via the directional control valve and the oil drain line 24 when the actuator is contracted.

When all the directional control valves 20a to 20c are fixed in the state of being switched to the neutral side, the pressurized oil flowing into the oil supply line 21 flows through the internal flow path 250 of the valve cover 20d and the directional control valve 20a to 20c through the one directional control valve 20a to 20c through one neutral flow path 22 formed as the neutral port of the flow control valve unit 10 is communicated with the flow control valve unit 10, And is supplied to the lift control valve unit 30 described above through the line 15. [

The flow rate control valve unit 10 is provided between the hydraulic pressure supply valve unit 20 and the elevation control valve unit 30 and is directly connected to the elevation control valve unit 30 side Adjust the flow rate of the supplied pressure oil. In other words, the pressurized oil from the hydraulic pump P is classified into the lift control valve unit 30 and the hydraulic pressure take-out valve unit 20 side during the passage of the pressurized oil to supply the hydraulic oil to the hydraulic takeoff valve unit 20 It plays a role.

To this end, the flow control valve unit 10 is provided therein with a hydraulic pressure takeoff valve unit supply side pressure line (not shown) connected to the P1 port (input port) of the lowermost control valves 20a to 20c of the hydraulic pressure takeoff valve unit 20 And a bypass line 14 connecting the elevation control valve unit supply side pressure line 15 and the bypass line 14 so as to fluidly connect the bypass line 14 and the input side branch line of the bypass line 14, And a flow rate regulator 13.

3, the flow rate regulator 13 may include a rotary type handle 130 extending outward from the valve block of the flow rate regulating valve unit 10. [ In this case, the handle can be rotated to the left and right to adjust the flow rate directly supplied to the hydraulic pressure takeoff valve unit 20 and the elevation control valve unit 30 in a stepwise manner. Through the three-point elevation device 40 and the hydraulic pressure The operating speed of the external working machine can be appropriately adjusted.

That is, the flow amount bypassed to the lift control valve unit supply side pressure line 15 via the bypass flow passage 14 by regulating the opening amount of the input side branch portion of the bypass flow passage 14 through the flow rate regulating valve 13 The elevating and lowering of the external working machine by the above-mentioned three-point elevating device 40 controlled by the elevating control valve unit 30 and the taking out of the external hydraulic pressure through the hydraulic pressure taking-out valve unit 20 are simultaneously realized .

The flow rate control valve unit 10 is preferably disposed below the lowermost directional control valve 20a of the directional control valves 20a to 20c arranged in a stacked manner forming the hydraulic pressure supply valve unit 20 as shown in Fig. And may be coupled to establish a fluid-flowable connection with the lowermost control valve 20a. That is, the hydraulic pressure take-out valve unit 20 and the hydraulic pressure take-out valve unit 20, it is preferable not to incur an effort such as an increase in cost or space.

The operation of the present invention will now be described with reference to FIGS. 5 to 6, wherein a double acting cylinder is applied as an actuator on the external working machine connected to the hydraulic takeoff valve unit.

5 and 6 are operational states showing the flow of pressurized fluid (working fluid) in accordance with the valve switching state of the hydraulic pressure supply valve unit, wherein the plurality of, preferably three, directional control valves constituting the hydraulic pressure- The flow of pressure will be described as an example when the valve (referred to as "first directional control valve") is switched to the actuator up side and when all directional control valves are switched to the neutral side.

5, when the first directional control valve 20a is switched to the ascending side of the actuator 60, when the actuator 60 of the first directional control valve 20a is switched on the ascending side, the hydraulic pump P A part of the supplied pressure oil is moved to the upside hydraulic chamber 602 of the actuator 60 through the oil passage of the second directional control valve 20a through the oil supply line 21 and is filled in the opposite hydraulic chamber 604 The pressure oil is drained to the oil tank T through the oil feed line 24.

The remaining part of the pressure oil supplied by the hydraulic pump P is supplied to the elevation control valve unit 30 via the bypass flow path 14 of the flow control valve unit 10 and the elevation control valve unit 30 And is drained to the side of the oil tank T through the internal circuit in the case where there is no operating command for the lifting device, or is supplied as the working fluid for raising or lowering the three-point lifting device 40 according to the switching state of the constituent valve elements.

At this time, when the amount of opening of the input-side branching portion of the bypass flow path 14 is adjusted through the flow rate control port 13 of the flow control valve unit 10, the flow rate supplied to the hydraulic pressure take- The flow rate bypassed to the elevating control valve unit supply side pressure line 15 via the flow path 14 is regulated so that the operating speed of the three-point elevating device 40 and the actuator 60 can be adjusted.

When all the directional control valves 20a to 20c are switched to the neutral position as shown in Fig. 6, some of the pressure oil supplied by the hydraulic pump P passes through the neutral line 22 constituted by the directional control valves, Unit 30 and the remaining part is supplied directly to the lift control valve unit 30 side via the bypass flow path 14 of the flow control valve unit 10. [ As a result, the entire amount of the pressurized oil supplied when the hydraulic pressure takeoff valve unit 20 is neutral is supplied to the elevation control valve unit 30. [

According to the embodiment of the present invention described above, a part is supplied to the hydraulic pressure take-out valve unit side by the flow rate control valve unit between the hydraulic pressure take-out valve unit and the lift control valve unit, The operation of the point elevating device and the operation of the external working machine using the hydraulic pressure can be realized simultaneously, and the operating speed of the three-point elevating device and the external working machine can also be appropriately adjusted.

That is, the lifting operation of the external working machine and the predetermined operation using the external working machine can be performed at the same time, so that the continuity and efficiency of the work can be improved and the working time can be greatly shortened. Since the flow control valve is constructed as a single module, it is possible to exclude the cost loss and the space required when the flow control valve is separately constructed.

In the foregoing detailed description of the present invention, only specific embodiments thereof have been described. It is to be understood, however, that the invention is not to be limited to the specific forms thereof, which are to be considered as being limited to the specific embodiments, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims. .

10: Flow control valve unit
12: Hydraulic pressure relief valve unit supply side pressure line
13: Flow control valve 14: Bypass passage
15: Lift control valve unit supply side pressure line
20: Hydraulic take-out valve unit
20a, 20b, 20c: direction control valve 20d: valve cover
21: Lubrication line 22: Neutral line
24: Drain line 30: Lift control valve unit
31: Unloading valve 32: Rising proportional solenoid
34: rising main spool 36: descending proportional solenoid
38: descending main spool 39: check valve
40: 3 point elevation device 41L, 41R: elevation cylinder
42L, 42R: lift arm 60: external working machine actuator
P: Hydraulic pump T: Oil tank

Claims (3)

A device mounted on the rear of the agricultural work vehicle and capable of simultaneously performing the elevating operation and the driving operation of the external working machine using hydraulic pressure,
An elevating control valve unit which is mounted on the rear end of the agricultural working vehicle and controls the supply of pressure oil for elevating driving to a three-point elevating device driven by hydraulic pressure;
And a control unit that is connected to the three-point elevation device and interrupts the extraction of the pressure oil outside the working vehicle for driving the external working machine driven by the hydraulic pressure, and supplies the pressure oil to the elevation control valve unit, A hydraulic takeoff valve unit; And
Wherein a bypass flow path is formed between the hydraulic pressure takeoff valve unit and the ascending / descending control valve unit for fluidly connecting the hydraulic pressure takeoff valve unit supply pressure line and the lift control valve unit supply pressure line in fluid communication therewith, And a flow control valve unit having a flow control valve for controlling the opening amount of the input side branching portion of the path flow path,
Wherein the flow rate of the hydraulic fluid bypassed to the pressure line on the supply side of the lift control valve unit is controlled through the bypass flow path and the external working machine is raised and lowered through the hydraulic pressure take- Hydraulic device for lifting and lowering the work machine.
The method according to claim 1,
The hydraulic pressure take-off valve unit includes:
A valve unit having a plurality of directional control valves stacked one on top of the other so that an internal spool is moved by an operation signal input from the outside to switch the flow state;
And a valve cover coupled to an upper portion of the uppermost directional control valve among the directional control valves and having an internal flow passage connected to the flow path of the uppermost directional control valve. Hydraulic device for extraction.
3. The method of claim 2,
And a flow control valve unit is connected to the lower portion of the directional control valve among the directional control valves arranged in layers so as to make fluid connection with the lowermost control valve. Device.

Images