Boarding ladder hydraulic system, control method and engineering vehicle

Abstract

The invention discloses a boarding ladder hydraulic system, a control method and an engineering vehicle. A pilot pump is connected with an energy accumulator, an electromagnetic valve I and a hydraulic control reversing valve I; the hydraulic control reversing valve I is connected with a lifting cylinder, and the electromagnetic valve I is connected with the control end of the hydraulic control reversing valve I; an electronic pump is connected with a hydraulic control reversing valve II, the hydraulic control reversing valve II is connected with the lifting cylinder, and a small cavity and a large cavity of the lifting cylinder are connected with an electromagnetic valve II through a first shuttle valve and a second shuttle valve; the electromagnetic valve II is connected with the control end of the hydraulic control reversing valve II; and the energy accumulator is connected with the small cavity of the lifting cylinder through an angle valve II, and the large cavity of the lifting cylinder is connected with an oil return pipeline through an angle valve III. According to the boarding ladder hydraulic system, the boarding ladder can be controlled to be stably lowered in the state that an engine is not started, and the boarding ladder is lifted and locked in posture through pilot pressure oil; and meanwhile, the boarding ladder can be automatically lowered in emergency situations such as emergency parking or fire, manual emergency lowering in the electric control failure state can be achieved, and the smoothness of an escape way and the life safety of personnel are guaranteed to the maximum extent.

Description

technical field

[0001] The invention relates to the technical field of engineering machinery, in particular to a hydraulic system of a boarding ladder, a control method and an engineering vehicle. Background technique

[0002] With the development of the world economy, the scale of open-pit mines continues to expand, and the role of large-tonnage mining equipment is increasingly apparent. Due to its large size and complex working conditions, it has high requirements for the boarding device. The cab of the mining equipment is located at a high position, and the distance between the walking platform and the ground is large. The special boarding ladder with high posture can not only meet the convenience and safety of people waiting for the car and get off the car, but also avoid collision accidents due to the proximity to the ground.

[0003] The problem that existing boarding ladder technology exists is:

[0004] The boarding ladder is generally driven by hydraulic pressure,...

Examples

Embodiment 1

[0031] like figure 1 As shown, a hydraulic system for the boarding ladder, the lifting cylinder 16 is connected to the boarding ladder 17, and the lifting cylinder 16 controls the lifting and lowering of the boarding ladder 17.

[0032] The pilot pump 1 is connected with a power unit 2, and the power unit 2 is an engine or an electric motor. A one-way valve I3 is installed on the oil outlet pipeline of the pilot pump 1, and the oil outlet of the one-way valve I3 is respectively connected with a solenoid valve I11 and a hydraulic control reversing valve I12. The first oil outlet of the hydraulic control reversing valve I12 is connected to the large cavity of the lifting cylinder 16, and the second oil outlet of the hydraulic control reversing valve I12 is connected to the small cavity of the lifting cylinder 16. Orifice I4 is installed on the pipeline between the oil inlet of solenoid valve I11 and the oil outlet of check valve I3, the oil return port of solenoid valve I11 is ...

Embodiment 2

[0036] A boarding ladder control method, using the boarding ladder hydraulic system described in Embodiment 1;

[0037] Lift the boarding ladder at 17:00;

[0038] When the solenoid valve I11 receives the command to lift the boarding ladder, the spool of the solenoid valve I11 works in the left position, and the pilot oil discharged from the pilot pump 1 flows into the hydraulic control reversing valve through the check valve I3, the throttle port I4, and the solenoid valve I11. The control end of I12 is used to adjust the position of the spool and the size of the valve port of the hydraulic control reversing valve I12 to control the operating speed of the lifting cylinder 16;

[0039] The pilot oil flows into the large chamber of the lift cylinder 16 through the one-way valve I3 and the hydraulic control reversing valve I12, the lifting cylinder 16 extends out, and the oil in the small cavity of the lifting cylinder 16 flows back to the oil tank 25 through the hydraulic contr...

Embodiment 3

[0052] An engineering vehicle adopts the hydraulic system of the boarding ladder described in the first embodiment.

[0053] The invention discloses a boarding ladder hydraulic system, a control method and an engineering vehicle, including a boarding ladder lifting system, a lowering system and an emergency lowering system. The lifting system is mainly composed of a pilot pump, a one-way valve, a solenoid valve, a hydraulic control reversing valve, and a safety overflow valve to complete the lifting and state locking functions of the waiting car ladder; the lowering system is composed of an electronic pump, Composed of a solenoid valve, a hydraulic control reversing valve, a safety overflow valve, and a back pressure valve, it completes the normal lowering of the boarding ladder when the engineering vehicle is electrified, and the automatic and stable lowering of the boarding ladder when the engineering vehicle is in an emergency stop; the emergency lowering system is mainly co...

technical field

[0001] The invention relates to the technical field of engineering machinery, in particular to a hydraulic system of a boarding ladder, a control method and an engineering vehicle. Background technique

[0002] With the development of the world economy, the scale of open-pit mines continues to expand, and the role of large-tonnage mining equipment is increasingly apparent. Due to its large size and complex working conditions, it has high requirements for the boarding device. The cab of the mining equipment is located at a high position, and the distance between the walking platform and the ground is large. The special boarding ladder with high posture can not only meet the convenience and safety of people waiting for the car and get off the car, but also avoid collision accidents due to the proximity to the ground.

[0003] The problem that existing boarding ladder technology exists is:

[0004] The boarding ladder is generally driven by hydraulic pressure,...

Examples

Embodiment 1

[0031] like figure 1 As shown, a hydraulic system for the boarding ladder, the lifting cylinder 16 is connected to the boarding ladder 17, and the lifting cylinder 16 controls the lifting and lowering of the boarding ladder 17.

[0032] The pilot pump 1 is connected with a power unit 2, and the power unit 2 is an engine or an electric motor. A one-way valve I3 is installed on the oil outlet pipeline of the pilot pump 1, and the oil outlet of the one-way valve I3 is respectively connected with a solenoid valve I11 and a hydraulic control reversing valve I12. The first oil outlet of the hydraulic control reversing valve I12 is connected to the large cavity of the lifting cylinder 16, and the second oil outlet of the hydraulic control reversing valve I12 is connected to the small cavity of the lifting cylinder 16. Orifice I4 is installed on the pipeline between the oil inlet of solenoid valve I11 and the oil outlet of check valve I3, the oil return port of solenoid valve I11 is ...

Embodiment 2

[0036] A boarding ladder control method, using the boarding ladder hydraulic system described in Embodiment 1;

[0037] Lift the boarding ladder at 17:00;

[0038] When the solenoid valve I11 receives the command to lift the boarding ladder, the spool of the solenoid valve I11 works in the left position, and the pilot oil discharged from the pilot pump 1 flows into the hydraulic control reversing valve through the check valve I3, the throttle port I4, and the solenoid valve I11. The control end of I12 is used to adjust the position of the spool and the size of the valve port of the hydraulic control reversing valve I12 to control the operating speed of the lifting cylinder 16;

[0039] The pilot oil flows into the large chamber of the lift cylinder 16 through the one-way valve I3 and the hydraulic control reversing valve I12, the lifting cylinder 16 extends out, and the oil in the small cavity of the lifting cylinder 16 flows back to the oil tank 25 through the hydraulic contr...

Embodiment 3

[0052] An engineering vehicle adopts the hydraulic system of the boarding ladder described in the first embodiment.

[0053] The invention discloses a boarding ladder hydraulic system, a control method and an engineering vehicle, including a boarding ladder lifting system, a lowering system and an emergency lowering system. The lifting system is mainly composed of a pilot pump, a one-way valve, a solenoid valve, a hydraulic control reversing valve, and a safety overflow valve to complete the lifting and state locking functions of the waiting car ladder; the lowering system is composed of an electronic pump, Composed of a solenoid valve, a hydraulic control reversing valve, a safety overflow valve, and a back pressure valve, it completes the normal lowering of the boarding ladder when the engineering vehicle is electrified, and the automatic and stable lowering of the boarding ladder when the engineering vehicle is in an emergency stop; the emergency lowering system is mainly co...

Images