CN218233634U

CN218233634U - Loader hydraulic system and loader

Info

Publication number: CN218233634U
Application number: CN202222449603.2U
Authority: CN
Inventors: 周进平; 雷念; 王允; 韦茂志; 覃海双
Original assignee: Guangxi Liugong Machinery Co Ltd
Current assignee: Guangxi Liugong Machinery Co Ltd
Priority date: 2022-09-16
Filing date: 2022-09-16
Publication date: 2023-01-06
Anticipated expiration: 2032-09-16

Abstract

The utility model relates to a loader hydraulic system, for solving the problem that the uncertain accessory flow demand of flow is difficult to deal with to the current loader hydraulic system single pump fuel feeding, the utility model discloses construct a loader hydraulic system and loader, wherein hydraulic system includes the main pump, with each lead valve that allies oneself with the main valve and be connected of distributing valve, the subpump, two three-way valves, the shuttle valve, two oil inlet ends of shuttle valve and two leading output oil ports of the attached antithetical couplet in the pilot valve are connected, the oil outlet end of shuttle valve is connected with the liquid accuse end of two three-way valves, the first hydraulic fluid port and the subpump pump mouth of two three-way valves are connected, the second hydraulic fluid port of two three-way valves is connected with main pump mouth main oil circuit through the confluence connection oil circuit, the third hydraulic fluid port and the hydraulic tank of two three-way valves are connected; one of the first oil ports of the two-position three-way valve is communicated with the second oil port or the third oil port, and the first oil port is communicated with the third oil port in a normal state. The utility model discloses loader hydraulic system can compromise the fuel feeding demand of the flow demand of the system of variation in size to energy-conserving advantage that can be better.

Description

Loader hydraulic system and loader

Technical Field

The utility model relates to a loader hydraulic system, more specifically say, relate to a loader hydraulic system and loader.

Background

The hydraulic system of the loader working device comprises a pressure oil source, a distribution valve connected with the pressure oil source, a movable arm oil cylinder and a rotary bucket oil cylinder, wherein a rotary bucket linkage main valve and a movable arm linkage main valve in the distribution valve are respectively connected with the rotary bucket oil cylinder and the movable arm oil cylinder. The bucket mounted at the front end of the movable arm is a common accessory of the loader, but in order to expand the functions of the loader, the front end of the movable arm can also use related accessories such as a breaking hammer, a snow sweeper and the like to replace the bucket, and the related accessories have hydraulic actuators to realize the related functions. In order to supply and control the associated accessory, a main accessory valve is usually also arranged on the distributor valve for connecting and controlling the accessory.

For a small-sized loader, a pressure oil source in a hydraulic system of a working device of the loader usually only comprises a single hydraulic pump, and the hydraulic pump is designed according to the flow rate required by the working device when the loader carries out shoveling operation. The flow rate required for selecting the accessory is uncertain for a loader main machine manufacturer, the flow rate required by the selected accessory during operation may be larger than the flow rate which can be provided by the hydraulic pump, or the sum of the flow rates required by the accessory, the boom cylinder and the rotary bucket cylinder during simultaneous operation is larger than the flow rate which can be provided by the hydraulic pump, so that the accessory cannot operate smoothly, and the operation efficiency is influenced.

For the problem of insufficient flow, the loader manufacturer can select a hydraulic pump with a larger flow (large flow) in the hydraulic pump selection mode, but the hydraulic pump with the excessive surplus displacement selection mode causes high manufacturing cost, and meanwhile, the large-displacement hydraulic pump causes energy loss and increases operation cost in the operation with a small flow demand (such as only conventional shovel operation or accessory equipment with a small flow).

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is that current loader hydraulic system single pump fuel feeding is difficult to deal with the problem of the uncertain accessory flow demand of flow, and provides a loader hydraulic system and loader.

The utility model discloses a realize that the technical scheme of its purpose is like: the hydraulic system of the loader is constructed, and comprises a distribution valve, a movable arm oil cylinder, a rotary bucket oil cylinder and accessory hydraulic actuators which are connected with corresponding main valves in the distribution valve, a main pump of which an oil suction port is connected with a hydraulic oil tank and of which a pump port supplies oil to the distribution valve through an oil path, and pilot valves connected with the main valves of the distribution valve, and is characterized by further comprising an auxiliary pump of which the oil suction port is connected with the hydraulic oil tank, a two-position three-way valve and a shuttle valve, wherein two oil inlet ends of the shuttle valve are connected with two pilot output oil ports of the accessory main valves in the pilot valves, an oil outlet end of the shuttle valve is connected with a hydraulic control end of the two-position three-way valve, a first oil port of the two-position three-way valve is connected with a pump port of the auxiliary pump, a second oil port of the two-position three-way valve is connected with a main oil path of the pump port of the main pump through a confluence connection oil path, and a third oil port of the two positions of the three-way valve is connected with the hydraulic oil tank; one of the first oil ports of the two-position three-way valve is communicated with the second oil port or the third oil port, and the first oil port is communicated with the third oil port in a normal state.

The utility model discloses in, when the loader is connected with the appurtenance and allies oneself with the main valve switching-over of the affiliation in the control distribution valve through the pilot valve, when making the appurtenance operation, the pilot pressure of the annex output of pilot valve acts on the liquid accuse end of two three-way valves through the shuttle valve, makes two three-way valve switching-overs, and the subpump is through two three-way valves and confluence connection oil circuit and main pump confluence, and common to the distribution valve fuel feeding, make its fuel feeding satisfy system flow demand. When the accessory tool does not work, the accessory link of the pilot valve does not have pilot pressure output, a first oil port and a third oil port of the two-position three-way valve are communicated, pressure oil output by the auxiliary pump flows to the hydraulic oil tank through the two-position three-way valve, low-pressure unloading of the auxiliary pump is achieved, and oil for a boom oil cylinder and a rotating bucket oil cylinder in the hydraulic system is supplied by a main pump. The power consumed by the low-pressure unloading of the auxiliary pump is smaller, and the energy consumption can be reduced.

The utility model discloses among the loader hydraulic system the switching control oil circuit between the liquid accuse end of shuttle valve and two three-way valves is provided with the two-way ooff valves of control switching control oil circuit break-make on the road. Further, the two-position two-way switch valve is an electromagnetic valve, and the two-position two-way switch valve can also be a rotary valve or a slide valve which is operated to be closed or conducted by manually rotating a valve rod. When the accessory installed on the loader is an accessory with a small flow demand and all flow demands of the system can be met by supplying oil through the main pump alone, the oil path from the shuttle valve to the hydraulic control end of the two-position three-way valve can be closed through the two-position two-way switch valve at the moment, the two-position three-way valve is not controlled by the accessory in the pilot valve, the auxiliary pump is always in a low-pressure unloading state, and energy waste caused by operation of the accessory during working is avoided.

The utility model discloses among the loader hydraulic system, the second hydraulic fluid port of two three-way valves and the confluence between the main pump mouth main oil circuit are connected and are provided with the check valve on the oil circuit, the check valve switches on to main pump mouth main oil circuit direction one-way. High-pressure oil output by the main pump is prevented from flowing to the two-position three-way valve and flowing to the hydraulic oil tank through leakage of the two-position three-way valve.

The utility model discloses among the loader hydraulic system, loader hydraulic system still includes priority valve, steering gear, the steering cylinder of being connected with the steering gear, the oil inlet and the main pump mouth of priority valve are connected, and the CE hydraulic fluid port of priority valve is connected with the oil inlet of steering gear, and the EF hydraulic fluid port of priority valve is connected with the oil inlet of distribution valve.

The utility model discloses among the loader hydraulic system, the subpump is the gear pump. Further, the main pump is a gear pump.

The utility model discloses a realize that the technical scheme of its purpose is like: a loader is constructed, and is characterized by comprising the loader hydraulic system.

Compared with the prior art, the utility model discloses loader hydraulic system can compromise the fuel feeding demand of the system flow demand of variation in size to energy-conserving advantage that can be better.

Drawings

Fig. 1 is a schematic diagram of an embodiment of a hydraulic system of a loader according to the present invention.

Fig. 2 is a schematic diagram of a hydraulic system of a loader according to the second embodiment of the present invention.

Part names and serial numbers in the figure:

the hydraulic control system comprises a hydraulic oil tank 1, a main pump 2, an auxiliary pump 3, a two-position two-way switch valve 4, a shuttle valve 5, a two-position three-way valve 6, a priority valve 7, a distribution valve 8, a rotary bucket oil cylinder 9, a movable arm oil cylinder 10, an accessory hydraulic actuator 11, a pilot valve 12, a steering oil cylinder 13, a steering gear 14 and a one-way valve 15.

Detailed Description

The following description of the embodiments refers to the accompanying drawings.

The first embodiment.

Fig. 1 shows a schematic diagram of a first embodiment of the hydraulic system of the loader according to the present invention. The hydraulic system of the dry loader comprises a hydraulic oil tank 1, a shuttle valve 5, a two-position three-way valve 6, a priority valve 7, a distribution valve 8, a rotary bucket oil cylinder 9, a movable arm oil cylinder 10, an accessory hydraulic actuator 11, a pilot valve 12, a steering oil cylinder 13 and a steering gear 14.

The oil inlet of the distribution valve 8 is connected with the EF oil port of the priority valve 7. The distribution valve 8 has a boom linkage main valve, a bucket linkage main valve, and an attachment linkage main valve, working ports of the triple main valve are connected to a boom cylinder 10, a bucket cylinder 9, and an attachment hydraulic actuator 11, respectively, and the attachment hydraulic actuator 11 may be a hydraulic motor, a hydraulic cylinder, or other hydraulic components.

The pilot valve 12 has three corresponding sets, namely a boom set, a swing bucket set and an auxiliary set, each set having two pilot output ports for connecting with two pilot hydraulic control ends of the main valve of the corresponding set. When the operating handle or the pedal corresponding to a certain connection of the pilot valve is operated and swung, one pilot output oil port of the two pilot output oil ports of the connection of the pilot valve outputs pressure oil which acts on the hydraulic control end of the corresponding connection main valve, so that the connection main valve is reversed and the corresponding hydraulic actuating part acts.

The steering oil cylinder 13 is connected with a steering gear 14, and an oil inlet of the steering gear 14 is supplied with oil from a CE oil port of the priority valve 7. In some embodiments, the diverter 14 may also be comprised of a combination of a flow amplifying valve and a small displacement diverter, or other hydraulic steering control mechanism.

In the present embodiment, the pressure oil source is constituted by a main pump 2 and a sub-pump 3, both of which have oil suction ports connected to a hydraulic oil tank, and the main pump 2 and the sub-pump 3 are driven by an engine or an electric motor. The main pump 2 and the auxiliary pump 3 are gear pumps, and a pump port of the main pump 2 is connected with an oil inlet of the priority valve 7 through a main oil path of the pump port of the main pump.

The pump port of the auxiliary pump 3 is connected with the first oil port of the two-position three-way valve 6, the second oil port of the two-position three-way valve 6 is connected with the main oil circuit of the pump port of the main pump, the third oil port of the two-position three-way valve 6 is connected with the hydraulic oil tank 1 through a pipeline, one first oil port of the two-position three-way valve 6 is selected to be communicated with the second oil port or the third oil port, and the first oil port and the third oil port are communicated in a normal state.

The hydraulic control end of the two-position three-way valve 6 is connected with the oil outlet end of the shuttle valve 5 through a switching control oil path, and two oil inlet ends of the shuttle valve 5 are correspondingly connected with two pilot output oil ports which are connected in an auxiliary manner in the pilot valve 12 respectively. When the auxiliary link of the pilot valve 12 is operated, the pilot pressure output by the auxiliary link of the pilot valve 12 is transmitted to the pilot control end of the two-position three-way valve 6 through the shuttle valve 5 and the switching control oil path, so that the two-position three-way valve is switched from the normal state to the confluence working position. When the two-position three-way valve works at the confluence working position, the first oil port and the second oil port of the two-position three-way valve are communicated.

In the present embodiment, when the attachment in the loader operation device is operated and controlled, the pilot pressure output from the attachment of the pilot valve 12 is transmitted to the hydraulic control end of the two-position three-way valve 6 via the shuttle valve 5 and the switching control oil path to change the direction of the pilot pressure, and the pressure oil output from the sub-pump 3 is merged with the pressure oil output from the main pump 2 to supply oil to the hydraulic components such as the steering cylinder, the boom cylinder, the bucket cylinder, and the attachment hydraulic actuator 11 on the loader, thereby satisfying the demand for a large flow rate of the system and efficiently operating each hydraulic actuator. When the accessory stops working, the flow required by the system is reduced, at the moment, the two-position three-way valve 6 is also reversed because the auxiliary connection of the pilot valve has no pilot pressure oil output, the auxiliary pump 3 directly unloads the low pressure of the hydraulic oil tank 1 through the two-position three-way valve 6, the power absorbed by the hydraulic system is reduced, and the energy consumption is reduced.

The second embodiment.

Fig. 2 shows a schematic diagram of a second embodiment of the hydraulic system of the loader according to the present invention. Compared with the previous embodiment, the loader hydraulic system in the embodiment is provided with the two-position two-way switch valve 4 on the switching control oil path between the oil outlet end of the shuttle valve 5 and the hydraulic control end of the two-position three-way valve 6, and the two-position two-way switch valve 4 can be an electromagnetic valve or a rotary valve or a slide valve which is operated to be closed or conducted by manually rotating a valve rod or a valve core. When the two-position two-way switch valve 4 is in a closed state, the pilot pressure oil pressure output by the auxiliary connection in the pilot valve cannot be transmitted to the hydraulic control end of the two-position three-way valve, and the two-position three-way valve is always kept in a normal state.

In this embodiment, when the hydraulic actuators in the attached accessories belong to small flow devices, and the flow rate supplied by the main pump 2 can satisfy the flow rate required by all the hydraulic actuators including the accessory hydraulic actuator 11, the operator can control to close the two-position two-way switching valve 4, so that the two-position three-way valve 6 is always kept in a normal state without being subjected to the accessory control in the pilot valve 12, and the sub-pump 3 is in a low-pressure unloading state, thereby avoiding energy consumption caused by excessive power absorption of the hydraulic system. When the hydraulic actuators in the installed accessories belong to large-flow devices, and the flow supplied by the main pump 2 cannot meet the flow of the system including the accessories, an operator can open the two-position two-way valve 4, so that when the accessories work, the main pump and the auxiliary pump are converged to supply oil to the whole system, and the oil consumption required by the normal work of each hydraulic actuator is met.

In this embodiment, the check valve 15 is disposed on the confluence connection oil path from the second oil port of the two-position three-way valve 6 to the main oil path at the pump port of the main pump, and the check valve 15 can prevent the pressure oil output by the main pump from flowing towards the two-position three-way valve and leaking through the two-position three-way valve to cause loss.

Claims

1. A hydraulic system of a loader comprises a distribution valve, a movable arm oil cylinder, a rotary bucket oil cylinder, an accessory hydraulic actuator, a main pump and a pilot valve, wherein the movable arm oil cylinder, the rotary bucket oil cylinder and the accessory hydraulic actuator are connected with corresponding main valves in the distribution valve; and one first oil port of the two-position three-way valve is communicated with the second oil port or the third oil port, and the first oil port is communicated with the third oil port in a normal state.

2. The hydraulic system of a loader according to claim 1 wherein a two-position two-way switching valve that controls the on/off of the switching control oil path is provided on the switching control oil path between the shuttle valve and the hydraulic control end of the two-position three-way valve.

3. The loader hydraulic system of claim 2, wherein the two-position, two-way switching valve is a solenoid valve.

4. The hydraulic system of a loader as claimed in claim 1 wherein a check valve is provided on the junction line between the second port of the two-position three-way valve and the main line of the main pump port, the check valve being in one-way communication with the main line of the main pump port.

5. The hydraulic system of a loader of claim 1 further comprising a priority valve, a diverter, and a steering cylinder connected to the diverter, wherein an oil inlet of the priority valve is connected to a pump port of the main pump, a CE port of the priority valve is connected to an oil inlet of the diverter, and an EF port of the priority valve is connected to an oil inlet of the distribution valve.

6. The loader hydraulic system of one of claims 1 to 5, whereby the secondary pump is a gear pump.

7. The loader hydraulic system of claim 6, wherein the main pump is a gear pump.

8. A loader characterized in that it has a loader hydraulic system according to any one of claims 1 to 7.