CN111056504A - Forklift hydraulic control system capable of realizing automatic driving and manual driving - Google Patents

Forklift hydraulic control system capable of realizing automatic driving and manual driving Download PDF

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Publication number
CN111056504A
CN111056504A CN202010112478.9A CN202010112478A CN111056504A CN 111056504 A CN111056504 A CN 111056504A CN 202010112478 A CN202010112478 A CN 202010112478A CN 111056504 A CN111056504 A CN 111056504A
Authority
CN
China
Prior art keywords
valve
port
oil
electromagnetic valve
way
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202010112478.9A
Other languages
Chinese (zh)
Inventor
沈勇
任大明
商飞
李凯
路振坡
王小虎
程然
王爱华
任佳璞
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xuzhou Xugong Special Construction Machinery Co Ltd
Original Assignee
Xuzhou Xugong Special Construction Machinery Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Xuzhou Xugong Special Construction Machinery Co Ltd filed Critical Xuzhou Xugong Special Construction Machinery Co Ltd
Priority to CN202010112478.9A priority Critical patent/CN111056504A/en
Publication of CN111056504A publication Critical patent/CN111056504A/en
Pending legal-status Critical Current

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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075Constructional features or details
    • B66F9/20Means for actuating or controlling masts, platforms, or forks
    • B66F9/22Hydraulic devices or systems
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/20Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors controlling several interacting or sequentially-operating members
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/06Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with two or more servomotors
    • F15B13/07Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with two or more servomotors in distinct sequence
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205Systems with pumps
    • F15B2211/2053Type of pump

Abstract

The invention discloses a forklift hydraulic control system capable of realizing automatic driving and manual driving, and belongs to the technical field of electric forklift hydraulic systems. The oil outlet of the pump is connected with a selector valve; the first oil way of the selector valve is connected with the multi-way valve, and the second oil way of the selector valve is connected with the priority valve; the priority valve oil outlet A is respectively connected with a first electromagnetic valve and a second electromagnetic valve; the first electromagnetic valve is connected with the lifting cylinder, and the second electromagnetic valve is connected with the tilting cylinder; the PF port of the priority valve is connected with the PF port of the multi-way valve through a one-way valve; the LS port of the priority valve is connected with the LS port of the multi-way valve; the multi-way valve is connected with the lifting cylinder and the tilting cylinder in a control way; the controller is electrically connected with the pump, the selector valve, the first electromagnetic valve and the second electromagnetic valve. The hydraulic system can realize automatic driving control and manual driving control, and simultaneously has an energy-saving mode of automatic driving; when the automatic driving fails, the manual driving mode is automatically started, and the maintenance efficiency is improved.

Description

Forklift hydraulic control system capable of realizing automatic driving and manual driving
Technical Field
The invention relates to a hydraulic system of an electric forklift, in particular to a hydraulic control system of the forklift, which can realize automatic driving and manual driving.
Background
It is a trend that electric counterweights fork trucks achieve unmanned automatic driving, and productivity can be improved. The hydraulic system of current manual driving mode is traditional mechanical valve, can't use the signal of telecommunication of controller to carry out proportional control, considers to switch the solenoid valve comprehensively, and the cost increases too much, in case hydraulic system breaks down simultaneously, and automatic driving's whole car just can't walk, can reduce production efficiency.
Disclosure of Invention
In order to solve the technical problems, the invention provides a forklift hydraulic control system capable of realizing automatic driving and manual driving. The invention can also keep the existing manual driving mode on the basis of the automatic driving mode, when the automatic driving mode fails due to faults, the whole vehicle is automatically switched to the independent manual driving mode, and the maintenance efficiency and the production progress are ensured.
The invention is realized by the following technical scheme: a forklift hydraulic control system capable of realizing automatic driving and manual driving comprises a pump, wherein an oil outlet of the pump is connected with a selector valve; the first oil path of the selector valve is connected with a multi-way valve, and the second oil path of the selector valve is connected with a priority valve; the oil outlet A of the priority valve is respectively connected with a first electromagnetic valve and a second electromagnetic valve; the first electromagnetic valve is connected with a lifting cylinder, and the second electromagnetic valve is connected with a tilting cylinder; the PF port of the priority valve is connected with the PF port of the multi-way valve through a one-way valve; the LS port of the priority valve is connected with the LS port of the multi-way valve; the multi-way valve is in control connection with the lifting cylinder and the tilting cylinder; the controller is electrically connected with the pump, the selector valve, the first electromagnetic valve and the second electromagnetic valve.
It further comprises the following steps: and the second oil path of the selector valve is also connected with a second overflow valve, and the second overflow valve is connected to an oil tank.
The priority valve is connected with a first overflow valve, and the first overflow valve is connected to the oil tank.
The port P3 of the first electromagnetic valve is connected with the port A of the priority valve, the port A3 of the first electromagnetic valve is connected with the large cavity oil inlet of the lifting cylinder, the port B3 of the first electromagnetic valve is blocked by oil plug, and the port T3 of the first electromagnetic valve is connected with the oil tank.
The port P4 of the second electromagnetic valve is connected with the port A of the priority valve, the port A4 of the second electromagnetic valve is connected with the oil inlet of the large cavity of the inclined cylinder, the port B4 of the second electromagnetic valve is connected with the oil inlet of the small cavity of the inclined cylinder, and the port T4 of the second electromagnetic valve is connected with the oil tank.
The port P of the multi-way valve is connected with the first oil path of the selector valve, the port A1 of the multi-way valve is connected with a large cavity oil inlet of the lifting cylinder, the port B1 of the multi-way valve is blocked by oil, the port A2 of the multi-way valve is connected with a large cavity oil inlet of the tilting cylinder, the port B2 of the multi-way valve is connected with a small cavity oil inlet of the tilting cylinder, and the port T of the multi-way valve is connected with an oil tank.
The PF port of the priority valve and the PF port of the multi-way valve are connected with an oil inlet of the steering system, and the LS port of the priority valve and the LS port of the road valve are connected with a control oil port of the steering system.
The pump is in transmission connection with the pump motor through a spline, and the controller is electrically connected with the pump motor.
The invention realizes the integration of two hydraulic control modes of the electric forklift, when the hydraulic system in the automatic driving mode breaks down, the selection valve can realize automatic power-off and automatically switch to the hydraulic system in manual driving, and a driver can still normally operate the forklift to work or drive to a maintenance point to perform fixed-point maintenance, thereby improving the maintenance efficiency.
Compared with the prior art, the invention has the beneficial effects that:
1. the hydraulic system can realize automatic driving control and manual driving control and has an energy-saving mode of automatic driving;
2. compared with a high-end electro-hydraulic proportional valve hydraulic system, the whole hydraulic control system has obvious cost advantage;
3. compared with pure manual driving, the unmanned operation of a plurality of electric forklifts can be realized simultaneously, and the production efficiency is greatly improved;
4. when the automatic driving fails, the manual driving mode is automatically started, and the maintenance efficiency is improved.
Drawings
FIG. 1 is a schematic diagram of the operation of the present invention;
in the figure: 1. a pump; 2. a selector valve; 3. a priority valve; 4. a first solenoid valve; 5. a second solenoid valve; 6. a lifting cylinder; 7. a tilt cylinder; 8. a multi-way valve; 9. a one-way valve; 10. a first overflow valve; 11. a second overflow valve; 12, a pump motor; 13. and a controller.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, a forklift hydraulic control system capable of realizing automatic driving and manual driving, a pump 1 is in transmission connection with a pump motor 12 through a spline, and an oil outlet of the pump 1 is connected with an oil inlet of a selector valve 2; a first oil way of the selector valve 2 is connected with an oil port P of the multi-way valve 8, and a second oil way of the selector valve 2 is connected with an oil port P of the priority valve 3; the second oil path of the selector valve 2 is also connected with a second overflow valve 11, the second overflow valve 11 is connected to the oil tank, and the second overflow valve 11 ensures the normal operation of the working hydraulic system. The port B of the priority valve 3 is connected to a first excess flow valve 10, and the first excess flow valve 10 is connected to a tank. An oil outlet A of the priority valve 3 is respectively connected with a first electromagnetic valve 4 and a second electromagnetic valve 5. The controller 13 is electrically connected to the pump motor 12, the selector valve 2, the first solenoid valve 4, and the second solenoid valve 5, and D0 corresponds to the pump motor, D1 corresponds to the selector valve, D2 corresponds to the first solenoid valve, and D3 corresponds to the second solenoid valve.
Specifically, the method comprises the following steps:
a P3 port of the first electromagnetic valve 4 is connected with an A port of the priority valve 3, an A3 port of the first electromagnetic valve 4 is connected with a large-cavity oil inlet of the lifting cylinder 6, a B3 port of the first electromagnetic valve 4 is blocked by an oil plug, and a T3 port of the first electromagnetic valve 4 is connected with an oil tank;
a port P4 of the second electromagnetic valve 5 is connected with a port A of the priority valve 3, a port A4 of the second electromagnetic valve 5 is connected with a large cavity oil inlet of the inclined cylinder 7, a port B4 of the second electromagnetic valve 5 is connected with a small cavity oil inlet of the inclined cylinder 7, and a port T4 of the second electromagnetic valve 5 is connected with an oil tank;
the A1 port of the multi-way valve 8 is connected with a large cavity oil inlet of the lifting cylinder 6, the B1 port of the multi-way valve 8 is blocked by an oil plug, the A2 port of the multi-way valve 8 is connected with a large cavity oil inlet of the tilting cylinder 7, the B2 port of the multi-way valve 8 is connected with a small cavity oil inlet of the tilting cylinder 7, and the T port of the multi-way valve 8 is connected with an oil tank;
the PF port of the priority valve 3 is connected to the PF port of the multiplex valve 8 through a check valve 9, and the LS port of the priority valve 3 is connected to the LS port of the multiplex valve 8. The PF port of the priority valve 3 and the PF port of the multi-way valve 8 are connected with an oil inlet of a steering system, and the LS port of the priority valve 3 and the LS port of the road valve 8 are connected with a control oil port of the steering system.
The first overflow valve 10 ensures the working pressure of the steering system, the priority valve mainly controls the whole vehicle to preferentially steer, and the one-way valve 9 controls the oil way of the steering system to be in one-way conduction, so that the integration of two hydraulic control modes of the electric forklift is realized. When the steering is carried out, the valve core of the priority valve is controlled to move left by the pressure difference at the two ends of the priority valve 3, so that more flow is used for a steering system through a PF port, when the steering is not carried out, the LS port of the priority valve directly returns to the oil tank, and the valve core of the priority valve automatically moves right to the position of a working hydraulic system under the action of a throttling port through the PF port.
The working principle is as follows:
the outlet of the pump 1 is selectively switched between automatic driving mode and manual driving mode through the selector valve 2, and the circuit signal for selectively switching is controlled by the controller 13.
The first electromagnetic valve 4 adopts an O-shaped function to control a lifting cylinder 6 of the electric fork-lift truck,
when the forklift is lifted, the controller 13 respectively outputs control signals to the pump motor 12, the selector valve 2 and the first electromagnetic valve 4, the pump motor 12 drives the pump 1 to operate, the selector valve 2 is switched to an automatic driving mode, after the first electromagnetic valve 4 is electrified, the valve core moves to the right, an oil way of the lifting action is switched on, and the whole forklift is lifted;
when a fork of the forklift needs to descend, the controller 13 outputs control signals to the pump motor 12, the selector valve 2 and the first electromagnetic valve 4 respectively, the pump motor 12 drives the pump 1 to operate, the selector valve 2 is switched to a manual driving mode, after the first electromagnetic valve 4 is powered on, the valve core moves to the left, the lower cavity of the lifting cylinder 6 is communicated with the oil return path, the forklift descends under the action of gravity, the oil inlet is not communicated, at the moment, the controller 13 controls the pump motor 12 to operate at a low speed, the selector valve 2 is powered off at the same time, and the main oil path returns oil through the multi-way valve 8; that is, when the forks are lowered, the pump 1 is unloaded through the multi-way valve 8.
The second electromagnetic valve 5 controls the tilting cylinder 7 to tilt forward or backward,
when the tilting cylinder needs to tilt forwards, the controller 13 outputs control signals to the pump motor 12, the selector valve 2 and the second electromagnetic valve 5 respectively, the pump motor 12 drives the pump 1 to operate, the selector valve 2 is switched to an automatic driving mode, the second electromagnetic valve 5 is electrified, the valve core moves rightwards, hydraulic oil flows to the tilting cylinder 7 through the pump 1, the selector valve 2 and the second electromagnetic valve 5 to tilt forwards, oil is fed into a large cavity of the tilting cylinder 7, and oil is fed into a small cavity of the tilting cylinder 7;
when the tilting cylinder needs to tilt backwards, the controller 13 outputs control signals to the pump motor 12, the selector valve 2 and the second electromagnetic valve 5 respectively, the pump motor 12 drives the pump 1 to operate, the selector valve 2 is switched to an automatic driving mode, the second electromagnetic valve 5 is electrified, the valve core moves leftwards, hydraulic oil flows from the pump 1, the selector valve 2 and the second electromagnetic valve 5 to the tilting cylinder 7 to tilt backwards, oil is fed into a small cavity of the tilting cylinder 7, and oil is fed into a large cavity of the tilting cylinder 7.
When the automatic driving mode is started, the lifting and descending actions, the forward tilting and backward tilting actions and the steering actions are not generated; the controller 13 will output control signals to the selector valve 2 and the pump motor 12, the selector valve 2 is automatically switched to the manual driving mode, the pump motor 12 drives the pump 1 to run at a low speed, and the pump 1 is unloaded through the multi-way valve 8, so as to reduce the heat generation of the hydraulic system, i.e. the energy-saving mode.
Can realize electric fork truck's two kinds of hydraulic control mode's integration through above scheme, when the hydraulic system of autopilot mode breaks down, the automatic power off can be realized to the selection valve, and automatic switch-over is to manual driving's hydraulic system, and the driver still can normally operate fork truck and carry out work, perhaps drives the maintenance point and carries out the maintenance of fixing a point, promotes maintenance efficiency.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (8)

1. A forklift hydraulic control system capable of realizing automatic driving and manual driving,
comprises a pump (1), wherein an oil outlet of the pump (1) is connected with a selector valve (2); a first oil path of the selector valve (2) is connected with a multi-way valve (8), and a second oil path of the selector valve (2) is connected with a priority valve (3);
an oil outlet A of the priority valve (3) is respectively connected with a first electromagnetic valve (4) and a second electromagnetic valve (5); the first electromagnetic valve (4) is connected with a lifting cylinder (6), and the second electromagnetic valve (5) is connected with a tilting cylinder (7); the PF port of the priority valve (3) is connected with the PF port of the multi-way valve (8) through a one-way valve (9); the LS port of the priority valve (3) is connected with the LS port of the multi-way valve (8);
the multi-way valve (8) is connected with the lifting cylinder (6) and the tilting cylinder (7) in a control mode;
the controller (13) is electrically connected with the pump (1), the selector valve (2), the first electromagnetic valve (4) and the second electromagnetic valve (5).
2. The forklift hydraulic control system capable of realizing automatic driving and manual driving according to claim 1, characterized in that: and a second overflow valve (11) is further connected to a second oil path of the selector valve (2), and the second overflow valve (11) is connected to an oil tank.
3. The forklift hydraulic control system capable of realizing automatic driving and manual driving according to claim 1, characterized in that: the priority valve (3) is connected with a first overflow valve (10), and the first overflow valve (10) is connected to an oil tank.
4. The forklift hydraulic control system capable of realizing automatic driving and manual driving according to claim 1, characterized in that: the P3 port of the first electromagnetic valve (4) is connected with the A port of the priority valve (3), the A3 port of the first electromagnetic valve (4) is connected with the large cavity oil inlet of the lifting cylinder (6), the B3 port of the first electromagnetic valve (4) is blocked by an oil plug, and the T3 port of the first electromagnetic valve (4) is connected with an oil tank.
5. The forklift hydraulic control system capable of realizing automatic driving and manual driving according to claim 1, characterized in that: the port P4 of the second electromagnetic valve (5) is connected with the port A of the priority valve (3), the port A4 of the second electromagnetic valve (5) is connected with a large cavity oil inlet of the inclined cylinder (7), the port B4 of the second electromagnetic valve (5) is connected with a small cavity oil inlet of the inclined cylinder (7), and the port T4 of the second electromagnetic valve (5) is connected with an oil tank.
6. The forklift hydraulic control system capable of realizing automatic driving and manual driving according to claim 1, characterized in that: the P port of the multi-way valve (8) is connected with a first oil path of the selector valve (2), the A1 port of the multi-way valve (8) is connected with a large cavity oil inlet of the lifting cylinder (6), the B1 port of the multi-way valve (8) is blocked by an oil plug, the A2 port of the multi-way valve (8) is connected with a large cavity oil inlet of the inclined cylinder (7), the B2 port of the multi-way valve (8) is connected with a small cavity oil inlet of the inclined cylinder (7), and the T port of the multi-way valve (8) is connected with an oil tank.
7. The forklift hydraulic control system capable of achieving automatic driving and manual driving according to claim 6, wherein: the PF port of the priority valve (3) and the PF port of the multi-way valve (8) are connected with an oil inlet of the steering system, and the LS port of the priority valve (3) and the LS port of the multi-way valve (8) are connected with a control oil port of the steering system.
8. The forklift hydraulic control system capable of realizing automatic driving and manual driving according to claim 1, characterized in that: the pump (1) is in transmission connection with the pump motor (12) through a spline, and the controller (13) is electrically connected with the pump motor (12).
CN202010112478.9A 2020-02-24 2020-02-24 Forklift hydraulic control system capable of realizing automatic driving and manual driving Pending CN111056504A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010112478.9A CN111056504A (en) 2020-02-24 2020-02-24 Forklift hydraulic control system capable of realizing automatic driving and manual driving

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010112478.9A CN111056504A (en) 2020-02-24 2020-02-24 Forklift hydraulic control system capable of realizing automatic driving and manual driving

Publications (1)

Publication Number Publication Date
CN111056504A true CN111056504A (en) 2020-04-24

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ID=70307752

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010112478.9A Pending CN111056504A (en) 2020-02-24 2020-02-24 Forklift hydraulic control system capable of realizing automatic driving and manual driving

Country Status (1)

Country Link
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112297985A (en) * 2020-11-04 2021-02-02 航天重型工程装备有限公司 Hydraulic lifting control device and method, storage medium and engineering vehicle

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112297985A (en) * 2020-11-04 2021-02-02 航天重型工程装备有限公司 Hydraulic lifting control device and method, storage medium and engineering vehicle

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