Hydraulic system for expansion of multifunctional work joint of hydraulic wheel type excavator

Abstract

The utility model discloses a hydraulic system for expanding a multifunctional work joint of a hydraulic wheel type excavator, and belongs to the technical field of engineering machinery. The wheel type hydraulic excavator overcomes the defects that in the prior art, a traditional wheel type hydraulic excavator has many standard configuration actions, the number and cost of integrated main control valve function links are limited, and the matching requirements of multifunctional accessories cannot be met. A main body structure of the hydraulic system comprises a steering pump, a main pump, a second electromagnetic reversing valve, a steering system and an accessory rotating system, the steering pump is connected with a priority valve, a CF port of the priority valve is connected with the steering system, an EF port of the priority valve is connected with the accessory rotating system, and a P7 port of the main pump is connected with an accessory opening and closing oil cylinder through a standby joint on a main control valve. A port P8 of the main pump is connected with an electromagnetic oil source valve set, the electromagnetic oil source valve set is connected with a second electromagnetic reversing valve, and a port A1 and a port A2 of the second electromagnetic reversing valve are connected with pilot control ports on the two sides of the standby unit respectively. The utility model is mainly applied to engineering machinery such as excavators and the like.

Description

Technical Field

[0001] This utility model belongs to the field of engineering machinery technology, and more specifically, it relates to a hydraulic system for multi-functional working extension of a hydraulic wheel excavator. Background Technology

[0002] Currently, domestic wheeled hydraulic excavators generally use multi-unit main control valves, with each unit controlling different actions (boom raising / lowering, stick retraction / extension, bucket retraction / extension, etc.). With the diversification of multi-functional attachments, the requirements for the number and functionality of the excavator's main control valve are increasing. For example, in existing hydraulic wheeled excavators with negative flow hydraulic systems, the integral main valve, in addition to standard actions, only has one spare unit (for adding a single-action breaker attachment). However, the shortcomings of this solution are: existing fully hydraulic wheeled excavators have many standard actions, and the number and cost of the integral main control valve's functional units are limited, making it impossible to meet the requirements of multi-functional attachments. Many excavators use external pump sources and plate valves for functional expansion, resulting in cumbersome system designs, significant modifications to the original vehicle, and high costs. Utility Model Content

[0003] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a hydraulic system for multi-functional working extension of hydraulic wheel excavators.

[0004] To achieve the above objectives, this utility model employs the following technical solution:

[0005] A hydraulic system for a multi-functional working link extension of a hydraulic wheel excavator includes a steering pump, a main pump, a second solenoid directional valve, a steering system, and an attachment slewing system. The steering pump is connected to a priority valve, the CF port of the priority valve is connected to the steering system, and the EF port of the priority valve is connected to the attachment slewing system. The P7 port of the main pump is connected to the attachment opening and closing cylinder through a spare link on the main control valve. The P8 port of the main pump is connected to a solenoid oil source valve group, which is connected to the second solenoid directional valve. The A1 and A2 ports of the second solenoid directional valve are respectively connected to the pilot control ports on both sides of the spare link.

[0006] Preferably, the attachment rotation system includes a first solenoid directional valve and an attachment rotation motor. The A4 port of the first solenoid directional valve is connected to the A port of the attachment rotation motor, the B4 port is connected to the B port of the attachment rotation motor, the P6 port is connected to the EF port of the priority valve, and the T port is connected back to the hydraulic oil tank.

[0007] Preferably, the steering system includes a steering gear, a central rotary joint, and a front axle steering cylinder, with the steering gear connected to the front axle steering cylinder via the central rotary joint.

[0008] Preferably, the steering gear is a load-sensitive steering gear.

[0009] Preferably, the P port of the second electromagnetic directional valve is connected to the safety handle on the electromagnetic oil source valve group, the A1 port is connected to the pilot control port XAo on the standby connection, the A2 port is connected to the pilot control port XBo on the standby connection, and the T2 port is connected back to the hydraulic oil tank.

[0010] Preferably, the working oil port Ao of the spare connection is connected to port A5 of the attachment opening and closing cylinder, and the working oil port Bo of the spare connection is connected to port B5 of the attachment opening and closing cylinder.

[0011] Preferably, the steering pump is a gear pump.

[0012] Compared with the prior art, the beneficial effects of this utility model are:

[0013] 1. Compared with the existing negative flow hydraulic system of excavators, a priority valve and a solenoid directional valve are added, and a steering gear is selected to expand the working power oil circuit. The main control valve remains unchanged. The use requirements of dual-action attachments are realized when the main control valve has only one spare connection.

[0014] 2. A stable power oil source output is provided through the priority valve and load-sensitive steering system, and the dual-action function attachment is used without adding a power source or a plate valve when only one backup connection of the main control valve is used.

[0015] In summary, this utility model simplifies the system, reduces costs, and meets the multifunctional needs of attachments. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the hydraulic system of this utility model;

[0017] Figure 2 for Figure 1 A magnified view of a section at point K;

[0018] Figure 3 for Figure 1 A magnified view of a section at point E in the middle.

[0019] In the diagram: 1. Steering pump; 2. Priority valve; 3. Steering gear; 4. First solenoid directional valve; 5. Second solenoid directional valve; 6. Attachment rotary motor; 7. Attachment opening and closing cylinder; 8. Main control valve; 9. Main pump; 10. Solenoid oil source valve assembly; 11. Radiator; 12. Hydraulic oil tank; 13. Central rotary joint; 14. Front axle steering cylinder; 81. Spare coupling; 101. Safety handle. Detailed Implementation

[0020] The present invention will be further described below through specific embodiments and in conjunction with the accompanying drawings.

[0021] Example 1:

[0022] like Figure 1-3 As shown, a hydraulic system for a multi-functional working extension of a hydraulic wheeled excavator includes a steering pump 1, a main pump 9, a second solenoid directional valve 5, a steering system, and an attachment slewing system. The steering pump 1 is connected to a priority valve 2. The CF port of the priority valve 2 is connected to the steering system, and the EF port of the priority valve 2 is connected to the attachment slewing system. The P7 port of the main pump 9 is connected to the attachment opening / closing cylinder 7 via a spare connection 81 on the main control valve 8. The P8 port of the main pump 9 is connected to a solenoid oil source valve group 10, which is connected to the second solenoid directional valve 5. The A1 and A2 ports of the second solenoid directional valve 5 are respectively connected to the pilot control ports on both sides of the spare connection 81. The priority valve 2 switches the oil circuit between the steering system and the working system. Through the pressure feedback control signal from the LS port of the steering gear 3, the second solenoid directional valve 5 and the spare connection 81 on the main control valve 8 provide oil circuit switching for the working system. The steering pump 1 is a gear pump.

[0023] Example 2:

[0024] A hydraulic system for a multi-functional working extension of a hydraulic wheel excavator differs from Embodiment 1 in that the attachment slewing system includes a first solenoid directional valve 4 and an attachment slewing motor 6. The A4 port of the first solenoid directional valve 4 is connected to the A port of the attachment slewing motor 6, the B4 port is connected to the B port of the attachment slewing motor 6, the P6 port is connected to the EF port of the priority valve 2, and the T port is connected back to the hydraulic oil tank 12.

[0025] Furthermore, the steering system includes a steering gear 3, a central rotary joint 13, and a front axle steering cylinder 14. The steering gear 3 is connected to the front axle steering cylinder 14 via the central rotary joint 13. The steering gear 3 is a load-sensitive steering gear.

[0026] Furthermore, the P port of the second electromagnetic directional valve 5 is connected to the safety handle 101 on the electromagnetic oil source valve assembly 10, the A1 port is connected to the pilot control port XAo on the backup coupling 81, the A2 port is connected to the pilot control port XBo on the backup coupling 81, and the T2 port is connected back to the hydraulic oil tank 12. The working oil port Ao of the backup coupling 81 is connected to the A5 port of the attachment opening and closing cylinder 7, and the working oil port Bo of the backup coupling 81 is connected to the B5 port of the attachment opening and closing cylinder 7.

[0027] The working principle of this utility model is as follows:

[0028] 1. When the vehicle is moving and turning:

[0029] At this time, oil flows from port P2 of steering pump 1 into port P3 of priority valve 2. When the steering wheel is turned, port LS1 of steering gear 3 senses the oil pressure of the steering load and feeds it back to port LS of priority valve 2. The pressure oil at port LS controls the working position of priority valve 2 to switch to the left position, so that the hydraulic oil enters port P4 of steering gear 3 through port CF of priority valve 2.

[0030] 11) When the right turn is operated, the oil is discharged through the R port of the steering gear 3, passes through the J1 port of the central rotary joint 13, enters the R1 port of the front axle steering cylinder 14, and then the oil returns through the L1 port of the front axle steering cylinder 14 to the J2 port of the central rotary joint 13 to the L port of the steering gear 3 and through the T port of the steering gear 3, so as to realize the right turn of the whole vehicle.

[0031] 12) When turning left, oil is discharged through the L port of steering gear 3, passes through the J2 port of central rotary joint 13, enters the L1 port of front axle steering cylinder 14, and then flows from the R1 port of front axle steering cylinder 14 to the J1 port of central rotary joint 13 to the R port of steering gear 3 and returns through the T port of steering gear 3 to achieve left turning of the whole vehicle.

[0032] II. When the vehicle is parked and the working device needs to be operated:

[0033] 21) During non-steering operation, there is no load pressure at the LS1 port of steering gear 3, the oil pressure at the LS port of priority valve 2 is zero, the working position of priority valve 2 remains in the right-hand position, and the oil output from the P2 port of steering pump 1 enters the P6 port of the first solenoid directional valve 4 through the EF port of priority valve 2. The two ends of the first solenoid directional valve 4 are connected to the electrical signal by pressing the button on the top of the pilot handle to control the switching of the working position:

[0034] When the left terminal of the first solenoid directional valve 4 is energized, the working pressure oil exits through port A4 of the first solenoid directional valve 4 and enters port A of the attachment rotary motor 6. Port B of the attachment rotary motor 6 is connected to port B4 of the first solenoid directional valve 4 and then returns through port T of the first solenoid directional valve 4, thereby realizing the left rotation of the attachment rotary motor 6.

[0035] When the right terminal of the first solenoid directional valve 4 is energized, the working pressure oil exits through port B4 of the first solenoid directional valve 4 and enters port B of the attachment rotary motor 6. Port A of the attachment rotary motor 6 is connected to port A4 of the first solenoid directional valve 4 and then returns through port T of the first solenoid directional valve 4, thereby realizing the right rotation of the attachment rotary motor 6.

[0036] 22) The pilot pressure oil from port P8 of the main pump 9 exits and enters port P5 of the solenoid oil source valve group 10. When the safety handle 101 of the solenoid oil source valve group 10 is opened, the pressure oil enters port P of the second solenoid directional valve 5 through port P1.

[0037] When the left side of the second solenoid directional valve 5 is energized, the working pressure oil exits through port A1 of the second solenoid directional valve 5 and enters the pilot control port XAo of the backup connection 81 on the main control valve 8, opening the main valve core of the backup connection 81, allowing the hydraulic oil of the main pump 9 to exit through port P7 and enter port P9 of the backup connection 81 on the main control valve 8. Then, through the working oil port Ao of the backup connection 81 on the main control valve 8, it enters port A5 of the attachment opening and closing cylinder 7. At the same time, port B5 of the attachment opening and closing cylinder 7 is connected to the working oil port Bo of the backup connection 81 on the main control valve 8, and then through the return oil port T of the main control valve 8, it is connected to the hydraulic oil tank 12 for return oil, realizing the extension action of the attachment opening and closing cylinder 7.

[0038] When the right side of the second solenoid directional valve 5 is energized, the working pressure oil exits through port A2 of the second solenoid directional valve 5 and enters the pilot control port XBo of the backup connection 81 on the main control valve 8, opening the main valve core of the backup connection 81, allowing the hydraulic oil of the main pump 9 to exit through port P7 and enter port P9 of the backup connection 81 on the main control valve 8. Then, through the working oil port Bo of the backup connection 81 on the main control valve 8, it enters port B5 of the attachment opening and closing cylinder 7. At the same time, port A5 of the attachment opening and closing cylinder 7 is connected to the working oil port Ao of the backup connection 81 on the main control valve 8, and then through the return oil port T of the main control valve 8, it is connected to the hydraulic oil tank 12 for return oil, realizing the inward movement of the attachment opening and closing cylinder 7.

[0039] The extension and retraction of the attachment cylinder 7 drive the opening and closing action of the attachment.

[0040] Since the integrated main valve of the wheeled hydraulic excavator with negative flow system has only one spare connection, which is insufficient to drive the rotation and opening / closing actions of the multi-functional attachment, this utility model realizes the expansion of the drive oil circuit from the steering system to achieve dual-path action of the attachment.

[0041] In summary, this utility model can solve the problem of insufficient number of functional connections of the existing main control valve. That is, the original negative flow system is equipped with an integral main valve with only one spare connection for the single action application of the breaker pipeline. In contrast, this utility model can meet the needs of the original excavator for all functional actions, while also meeting the needs of attachments with dual action (rotation + clamping composite action) functions. The solution is simplified and cost-effective.

Claims

1. A hydraulic system for multi-functional work extension of a hydraulic wheeled excavator, characterized in that: The system includes a steering pump (1), a main pump (9), a second solenoid directional valve (5), a steering system, and an attachment rotation system. The steering pump (1) is connected to a priority valve (2). The CF port of the priority valve (2) is connected to the steering system, and the EF port of the priority valve (2) is connected to the attachment rotation system. The P7 port of the main pump (9) is connected to the attachment opening and closing cylinder (7) through the spare connection (81) on the main control valve (8). The P8 port of the main pump (9) is connected to the solenoid oil source valve group (10). The solenoid oil source valve group (10) is connected to the second solenoid directional valve (5). The A1 port and A2 port of the second solenoid directional valve (5) are respectively connected to the pilot control ports on both sides of the spare connection (81).

2. The hydraulic system for multi-functional work extension of a hydraulic wheeled excavator according to claim 1, characterized in that: The attachment rotation system includes a first solenoid directional valve (4) and an attachment rotation motor (6). The A4 port of the first solenoid directional valve (4) is connected to the A port of the attachment rotation motor (6), the B4 port is connected to the B port of the attachment rotation motor (6), the P6 port is connected to the EF port of the priority valve (2), and the T port is connected back to the hydraulic oil tank (12).

3. The hydraulic system for multi-functional work extension of a hydraulic wheeled excavator according to claim 1, characterized in that: The steering system includes a steering gear (3), a central rotary joint (13), and a front axle steering cylinder (14). The steering gear (3) is connected to the front axle steering cylinder (14) through the central rotary joint (13).

4. The hydraulic system for multi-functional work extension of a hydraulic wheeled excavator according to claim 3, characterized in that: The steering gear (3) is a load-sensitive steering gear.

5. The hydraulic system for multi-functional working extension of a hydraulic wheeled excavator according to any one of claims 1-4, characterized in that: The P port of the second electromagnetic reversing valve (5) is connected to the safety handle (101) on the electromagnetic oil source valve group (10), the A1 port is connected to the pilot control port XAo on the standby connection (81), the A2 port is connected to the pilot control port XBo on the standby connection (81), and the T2 port is connected back to the hydraulic oil tank (12).

6. The hydraulic system for multi-functional work extension of a hydraulic wheeled excavator according to claim 5, characterized in that: The working port Ao of the spare coupler (81) is connected to port A5 of the attachment opening and closing cylinder (7), and the working port Bo of the spare coupler (81) is connected to port B5 of the attachment opening and closing cylinder (7).

7. The hydraulic system for multi-functional work extension of a hydraulic wheeled excavator according to any one of claims 1-4, characterized in that: The steering pump (1) is a gear pump.

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