CN113148914A - Forklift potential energy recovery and release integrated device and working method - Google Patents

Abstract

The invention discloses a device for integrating potential energy recovery and release of a forklift and a working method, wherein the device integrates the recovery and release of gravitational potential energy, and realizes the recovery and release of energy through the same set of energy recovery and release unit: when the lifting oil cylinder drives the heavy object to be lowered, the hydraulic pump motor is used as a motor, the motor generator is used as a generator, pressure oil in the second rodless cavity of the lifting oil cylinder flows into the motor to drive the generator to work, and output electric energy is stored in the storage battery; or the pressure oil of the second rodless cavity of the lifting oil cylinder flows into the first rodless cavity of the tilting oil cylinder to drive the tilting oil cylinder to act, and the energy recovery is completed. In the lifting process, the motor generator works in a motor state to draw electric energy from the storage battery, the hydraulic pump motor works in a hydraulic pump state to improve pressure oil for the system, a piston rod of the lifting oil cylinder or a piston rod of the inclined oil cylinder is pushed to extend out to complete the lifting action, and the energy releasing process is carried out at the moment.

Description

Forklift potential energy recovery and release integrated device and working method

technical field

The invention relates to an integrated device and a working method for recovering and releasing potential energy of a forklift.

Background technique

Forklift refers to various wheeled handling vehicles for loading, unloading, stacking and short-distance transportation of palletized goods. It is a commonly used lifting tool and is usually driven by an engine or motor. Its working principle is the engine or motor. The hydraulic pump is driven to generate hydraulic energy, so that the lifting cylinder converts the hydraulic energy into the gravitational potential energy of the cargo.

The electric forklift uses the battery as energy, and uses the electric motor instead of the engine to drive the hydraulic system to complete the work process of lifting, lowering, transferring, and unloading the goods. Since the forklift contains a lot of potential energy in the process of driving the heavy object down, the traditional forklift consumes this part of the energy on the throttle valve port, which causes a lot of energy loss on the one hand, and also increases the oil temperature on the other hand. , affecting the life of hydraulic components and oil, and may cause problems such as leakage and unstable work. At present, for the research on the potential energy of forklifts, some studies use hydraulic accumulators to store the pressure oil of the lifting cylinder in the process of lowering the heavy objects. The controllability changes during the descending process of the object; another part of the research adopts an electrical energy recovery method, using a separate hydraulic motor-generator connected to the rodless cavity of the lifting cylinder; when the lifting cylinder drives the heavy object to descend, the lifting The hydraulic oil in the rodless cavity of the lift cylinder flows into the hydraulic motor to drive the generator to generate electricity, and the electrical energy is stored in the battery. During lifting or other operating conditions, the stored electrical energy is released. In this working method, the energy recovery system and the release system are two different systems, and there are multiple energy conversions, the system is complex and the efficiency is low. In order to simplify the system and improve the energy utilization efficiency, the integration of recovery and release is an important research direction.

SUMMARY OF THE INVENTION

The present invention provides an integrated device and working method for recovering and releasing potential energy of a forklift, which overcomes the shortcomings of the background technology. One of the technical solutions adopted by the present invention to solve its technical problems is:

Forklift potential energy recovery and release integrated device, it includes: tilting cylinder, lifting cylinder, three-position four-way electromagnetic reversing valve, first two-position two-way electromagnetic reversing valve, second two-position two-way electromagnetic reversing valve , energy recovery and release unit, motor controller and battery, the tilting oil cylinder includes a first rod cavity and a first rodless cavity, the three-position four-way electromagnetic reversing valve is connected with the first rod cavity and the first rodless cavity. The rod cavity, the second two-position two-way electromagnetic reversing valve and the energy recovery and release unit are all connected, the energy recovery and release unit is connected with the motor controller, and the motor controller is connected with the battery; the lifting cylinder includes a second rod cavity and the second rodless cavity, the second rodless cavity is connected with the first two-position two-way electromagnetic reversing valve, the first two-position two-way electromagnetic reversing valve and the second two-position two-way electromagnetic reversing valve, energy recovery Both are connected with the release unit, and the second two-position two-way electromagnetic reversing valve is connected with the energy recovery and release unit.

In a preferred embodiment: the energy recovery and release unit includes a hydraulic pump motor, a motor generator and a first oil tank, the hydraulic pump motor and the motor generator, the three-position four-way electromagnetic reversing valve, and the first oil tank are all in phase connected, the motor generator is connected to the motor controller.

In a preferred embodiment, the hydraulic pump motor and the motor generator are arranged coaxially.

In a preferred embodiment: the device further includes a first check valve and a second check valve, the inlet of the first check valve is connected to the hydraulic pump motor and the outlet of the second check valve, and the outlet is connected to the third check valve. The four-way electromagnetic reversing valve and the second two-position two-way electromagnetic reversing valve are connected; the inlet of the second one-way valve is connected to the first two-position two-way electromagnetic reversing valve and the second two-position two-way electromagnetic reversing valve The valves are all connected, and the outlet of the second one-way valve is connected with the hydraulic pump motor.

In a preferred embodiment, the device further includes a throttle valve, which is connected between the first two-position two-way electromagnetic reversing valve and the inlet of the second one-way valve.

In a preferred embodiment: the device further includes a relief valve and a second oil tank, the relief valve inlet is connected to the hydraulic pump motor, the first check valve inlet and the second check valve outlet, the relief valve outlet is connected to The second fuel tank is connected.

In a preferred embodiment: the device further comprises an oil replenishment check valve and a third oil tank, the inlet of the oil replenishment check valve is connected to the third oil tank, the outlet of the oil replenishment check valve is connected with the overflow valve inlet, the hydraulic pump The motor and the inlet of the first one-way valve are all connected.

In a preferred embodiment, there are two lift cylinders, and the second rodless chambers of the two lift cylinders are both connected to the first two-position two-way electromagnetic reversing valve.

The second of the technical solutions adopted by the present invention to solve its technical problems is:

An integrated working method for recovering and releasing potential energy of a forklift truck, which applies the integrated device for recovering and releasing potential energy of a forklift truck, including:

Forklift potential energy recovery has two states:

When the lift cylinder is driven to lower the heavy objects, the three-position four-way electromagnetic reversing valve is in the neutral position, and the tilting cylinder does not work. The reversing valve is not energized, and the pressure oil in the second rodless chamber of the lift cylinder flows into the hydraulic pump motor through the first two-position two-way electromagnetic reversing valve, the throttle valve and the second one-way valve, and the hydraulic pump motor 11 Used as a motor, the motor generator is in the state of generating electricity, and the electric energy is stored in the battery through the motor controller; due to the existence of the hydraulic pump motor, the pressure difference between the two ends of the throttle valve can be adjusted, so as to realize the precise control of the descending speed;

or,

When the lifting cylinder is driven to lower the heavy objects, the left or right position of the three-position four-way electromagnetic reversing valve works, the tilting cylinder is in working state and its working pressure is lower than the pressure of the second rodless cavity of the lifting cylinder. At this time, both the first two-position two-way electromagnetic reversing valve and the second two-position two-way electromagnetic reversing valve are energized, and the pressure oil in the second rodless cavity of the lifting cylinder passes through the first two-position two-way electromagnetic reversing valve, The left or right position of the second two-position two-way electromagnetic reversing valve and the three-position four-way electromagnetic reversing valve flow into the first rodless cavity of the tilting cylinder, and the tilting cylinder drives the weight to tilt forward and backward. tilt;

There are two states when energy is released:

When the lift cylinder is driven to lift the fork, the first two-position two-way electromagnetic reversing valve and the second two-position two-way electromagnetic reversing valve are both energized, and the energy stored in the battery is supplied to the motor generator to generate electricity. Make it in the electric motor state, the hydraulic pump motor is used as a hydraulic pump, the hydraulic pump outputs pressure oil to the outside, and the pressure oil passes through the first one-way valve, the second two-position two-way electromagnetic reversing valve and the first two-position two-way electromagnetic exchange. The direction valve enters the second rodless cavity of the lift cylinder, pushes the lift cylinder to drive the fork to complete the lifting action, and realizes the reuse of recovered energy;

or,

When the driving tilt cylinder works but the lift cylinder does not work, neither the first two-position two-way electromagnetic reversing valve nor the second two-position two-way electromagnetic reversing valve is energized, and the three-position four-way electromagnetic reversing valve is energized, and it is at the left Position or right position work, at this time, the energy stored in the battery is supplied to the motor-generator, so that it is in the motor state, the hydraulic pump motor is used as a hydraulic pump, the hydraulic pump outputs pressure oil to the outside, and the pressure oil output from the hydraulic pump passes through The first one-way valve and the three-position four-way electromagnetic reversing valve flow into the first rodless cavity of the tilting oil cylinder, which drives the fork to tilt forward or backward to realize the reuse of recovered energy.

Compared with the background technology, the technical solution has the following advantages:

1. The device integrates the recovery and release of gravitational potential energy, and realizes the recovery and release of energy through the same set of energy recovery and release units: in the process of lowering the heavy objects driven by the lifting cylinder, the hydraulic pump motor is used as a motor to generate electricity. The machine is used as a generator, the pressure oil in the second rodless cavity of the lifting cylinder flows into the motor to drive the motor to drive the generator to work, and the output electric energy is stored in the battery to complete the energy recovery. During the lifting process, the motor-generator works in the state of electric motor, draws electric energy from the battery, and the hydraulic pump motor works in the state of hydraulic pump, which increases the pressure oil for the system, pushes the piston rod of the lifting cylinder to extend, and completes the lifting action. This is the release process of energy.

2. In terms of energy release, on the one hand, it can be released through the energy recovery and release unit to continue to push the lifting cylinder to work; on the other hand, when the working pressure of the tilting cylinder is lower than the pressure of the second rodless chamber of the lifting cylinder, The pressure oil in the second rodless cavity of the lift cylinder can directly flow into the tilting cylinder, and push the tilting cylinder to complete the related operations. At this time, because of the direct use of pressure oil-pressure oil, there is no energy conversion, so the efficiency is high.

Description of drawings

The present invention will be further described below with reference to the accompanying drawings and embodiments.

FIG. 1 shows a block diagram of the overall structure of a device for integrating potential energy recovery and release of a forklift truck according to a preferred embodiment.

Detailed ways

In the claims, description and the above drawings of the present invention, unless otherwise clearly defined, the terms "first", "second" or "third" are used to distinguish different objects, rather than used for Describe a specific order.

In the claims, description and the above drawings of the present invention, unless otherwise expressly defined, the terms "center", "horizontal", "longitudinal", "horizontal", "vertical" and "top" are used for directional words. , "bottom", "inside", "outside", "up", "down", "front", "rear", "left", "right", "clockwise", "counterclockwise", etc. The positional relationship is based on the orientation and positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation or be constructed and operated in a particular orientation. , so it should not be construed as limiting the specific protection scope of the present invention.

In the claims, description and the above drawings of the present invention, unless otherwise clearly defined, the terms "fixed connection" and "fixed connection" should be understood in a broad sense, that is, there is no displacement relationship and relative rotation relationship between the two. Any connection means, that is to say including non-removable fixed connection, detachable fixed connection, integrated and fixed connection by other means or elements.

In the claims, description and the above-mentioned drawings of the present invention, if the terms "including", "having" and their modifications are used, it is intended to mean "including but not limited to".

Please refer to FIG. 1 , a preferred embodiment of an integrated device for recovering and releasing potential energy of a forklift. The described device for recovering and releasing integrated potential energy of a forklift includes a tilting cylinder 1 , a lifting cylinder 2.1 and 2.2 , Three-position four-way electromagnetic reversing valve 3 , first two-position two-way electromagnetic reversing valve 4 , second two-position two-way electromagnetic reversing valve 5 , energy recovery and release unit 20 , motor controller 13 and battery 14 .

The tilting oil cylinder 1 includes a first rod cavity and a first rodless cavity, and the three-position four-way electromagnetic reversing valve 3 is exchanged with the first rod cavity, the first rodless cavity, and the second two-position two-way electromagnetic switch. The valve 5 is connected to the energy recovery and release unit 20, the energy recovery and release unit 20 is connected to the motor controller 13, and the motor controller 13 is connected to the battery 14; the lifting cylinders 2.1 and 2.2 include the second rod chamber and the first Two rodless chambers, the second rodless chamber is connected with the first two-position two-way electromagnetic reversing valve 4, the first two-position two-way electromagnetic reversing valve 4 and the second two-position two-way electromagnetic reversing valve 5, energy The recovery and release units 20 are both connected, and the second 2/2-way electromagnetic reversing valve 5 is connected with the energy recovery and release unit 20 .

In this embodiment, two lifting cylinders 2.1 and 2.2 are provided, and the second rodless chambers of the two lifting cylinders 2.1 and 2.2 are both connected to the first two-position two-way electromagnetic reversing valve 4 .

In this embodiment, the energy recovery and release unit 20 includes a hydraulic pump motor 11, a motor generator 12 and a first oil tank 15, the hydraulic pump motor 11 and the motor generator 12, a three-position four-way electromagnetic reversing valve 3, a third A fuel tank 15 is connected to each other, and the motor generator 12 is connected to the motor controller 13 . Preferably, the hydraulic pump motor 11 and the motor generator 12 are arranged coaxially to reduce friction and improve efficiency.

In this embodiment, the device further includes a first check valve 6 and a second check valve 7, the inlet of the first check valve 6 is connected to the hydraulic pump motor 11 and the outlet of the second check valve 7, and the outlet of the first check valve 6 is connected to the hydraulic pump motor 11 and the outlet of the second check valve 7. It is connected with the three-position four-way electromagnetic reversing valve 3 and the second two-position two-way electromagnetic reversing valve 5; the inlet of the second one-way valve 7 is connected with the first two-position two-way electromagnetic reversing valve 4, the second two-way electromagnetic reversing valve The two-way electromagnetic reversing valve 5 is connected to each other, and the outlet of the second one-way valve 7 is connected to the hydraulic pump motor 11 .

In this embodiment, the device further includes a throttle valve 8 , and the throttle valve 8 is connected between the first two-position two-way electromagnetic reversing valve 4 and the inlet of the second one-way valve 7 .

In this embodiment, the device further includes a relief valve 9 and a second oil tank 17. The inlet of the relief valve 9 is connected to the hydraulic pump motor 11, the inlet of the first check valve 6 and the outlet of the second check valve 7. The outlet of the valve 9 is connected to the second oil tank 17 .

In this embodiment, the device further includes a fuel check valve 10 and a third fuel tank 16 , the inlet of the fuel check valve 10 is connected to the third fuel tank 16 , and the outlet of the fuel check valve 10 is connected to the inlet of the relief valve 9 . , The hydraulic pump motor 11 and the inlet of the first one-way valve 6 are all connected.

The working method of the forklift potential energy recovery and release integrated device includes:

Forklift potential energy recovery has two states:

When the operating handle of the forklift drives the lifting cylinders 2.1 and 2.2 to lower the heavy objects, the three-position four-way electromagnetic reversing valve 3 is in the neutral position, and the tilting cylinder 1 does not work. At this time, the first two-position two-way electromagnetic reversing valve 4 is energized, the second two-position two-way electromagnetic directional valve 5 is not energized, and the pressure oil in the second rodless chamber of the lifting cylinders 2.1 and 2.2 passes through the first two-position two-way electromagnetic directional valve 4, throttle valve 8, After the second check valve 7 flows into the hydraulic pump motor 11, the hydraulic pump motor 11 is used as a motor to drive the motor generator 12 to generate electricity, and the electric energy is stored in the battery 14 through the motor controller 13; If there is, the pressure difference between the two ends of the throttle valve 8 can be adjusted, so as to realize the precise control of the descending speed;

or,

When the lifting cylinders 2.1 and 2.2 are driven to lower the heavy objects, the left or right position of the three-position four-way electromagnetic reversing valve 3 works, the tilting cylinder 1 is in working state and its working pressure is lower than that of the lifting cylinders 2.1 and 2.2. The pressure of the second rodless chamber, at this time, the first two-position two-way electromagnetic reversing valve 4 and the second two-position two-way electromagnetic reversing valve 5 are both energized, and the pressure of the second rodless chamber of the lift cylinders 2.1 and 2.2 The oil flows into the first position of the tilt cylinder 1 after passing through the left or right position of the first two-position two-way electromagnetic reversing valve 4, the second two-position two-way electromagnetic reversing valve 5 and the three-position four-way electromagnetic reversing valve 3. In the rodless cavity, the tilting cylinder 1 drives the heavy object to tilt forward and backward;

There are two states when energy is released:

When the lift cylinders 2.1 and 2.2 are driven to lift the forks, the first two-position two-way electromagnetic reversing valve 4 and the second two-position two-way electromagnetic reversing valve 5 are both energized, and the energy stored in the battery 14 at this time is energized. Supply the motor-generator 12 to make it in the motor state, the hydraulic pump motor 11 is used as a hydraulic pump, the hydraulic pump outputs pressure oil to the outside, and the pressure oil passes through the first one-way valve 6 and the second two-position two-way electromagnetic reversing valve 5 and the first two-position two-way electromagnetic reversing valve 4 enter the second rodless cavity of the lifting cylinders 2.1 and 2.2, and push the lifting cylinders 2.1 and 2.2 to drive the forks to complete the lifting action, realizing the reuse of recovered energy. ;

or,

When driving the tilting cylinder 1 to work and the lifting cylinder 2 not working, the first two-position two-way electromagnetic reversing valve 4 and the second two-position two-way electromagnetic reversing valve 5 are not energized, and the three-position four-way electromagnetic reversing valve 3. Power on and work in the left or right position. At this time, the energy stored in the battery 14 is supplied to the motor-generator 12 to make it in the motor state. The hydraulic pump motor 11 is used as a hydraulic pump, and the hydraulic pump outputs pressure oil to the outside. , the pressure oil output by the hydraulic pump flows into the first rodless cavity of the tilting cylinder 1 after passing through the first one-way valve 6 and the three-position four-way electromagnetic reversing valve 3, so that it drives the fork to tilt forward or backward. Realize the reuse of recovered energy.

The above descriptions are only preferred embodiments of the present invention, so the scope of implementation of the present invention cannot be limited accordingly, that is, equivalent changes and modifications made according to the patent scope of the present invention and the contents of the description should still be covered by the present invention. within the range.

Claims (9)

1. Fork truck potential energy is retrieved and release integrated device, its characterized in that: it includes: the device comprises a tilting oil cylinder, a lifting oil cylinder, a three-position four-way electromagnetic directional valve, a first two-position two-way electromagnetic directional valve, a second two-position two-way electromagnetic directional valve, an energy recovery and release unit, a motor controller and a storage battery, wherein the tilting oil cylinder comprises a first rod cavity and a first rodless cavity; the lifting oil cylinder comprises a second rod cavity and a second rodless cavity, the second rodless cavity is connected with a first two-position two-way electromagnetic directional valve, the first two-position two-way electromagnetic directional valve is connected with the second two-position two-way electromagnetic directional valve and the energy recovery and release unit, and the second two-position two-way electromagnetic directional valve is connected with the energy recovery and release unit.

2. The integrated forklift potential energy recovery and release device of claim 1, wherein: the energy recovery and release unit comprises a hydraulic pump motor, a motor generator and a first oil tank, the hydraulic pump motor is connected with the motor generator, the three-position four-way electromagnetic directional valve and the first oil tank, and the motor generator is connected with the motor controller.

3. The integrated forklift potential energy recovery and release device of claim 2, wherein: the hydraulic pump motor is arranged coaxially with the motor generator.

4. The integrated forklift potential energy recovery and release device of claim 3, wherein: the device also comprises a first one-way valve and a second one-way valve, wherein the inlet of the first one-way valve is connected with the hydraulic pump motor and the outlet of the second one-way valve, and the outlet of the first one-way valve is connected with the three-position four-way electromagnetic reversing valve and the second two-position two-way electromagnetic reversing valve; and the inlet of the second one-way valve is connected with both the first two-position two-way electromagnetic reversing valve and the second two-position two-way electromagnetic reversing valve, and the outlet of the second one-way valve is connected with the hydraulic pump motor.

5. The integrated forklift potential energy recovery and release device of claim 4, wherein: the device also comprises a throttle valve which is connected between the first two-position two-way electromagnetic directional valve and the inlet of the second one-way valve.

6. The integrated forklift potential energy recovery and release device of claim 5, wherein: the device also comprises an overflow valve and a second oil tank, wherein the inlet of the overflow valve is connected with the hydraulic pump motor, the inlet of the first one-way valve and the outlet of the second one-way valve, and the outlet of the overflow valve is connected with the second oil tank.

7. The integrated forklift potential energy recovery and release device of claim 6, wherein: the device still includes oil supplementing check valve and third oil tank, and this oil supplementing check valve import links to each other with the third oil tank, and this oil supplementing check valve export all links to each other with overflow valve import, hydraulic pump motor, first check valve import.

8. The integrated forklift potential energy recovery and release device of claim 7, wherein: the two lifting oil cylinders are arranged, and second rodless cavities of the two lifting oil cylinders are connected with the first two-position two-way electromagnetic directional valve.

9. An integrated forklift potential energy recovery and release working method applying the integrated forklift potential energy recovery and release device of any one of claims 7 to 8, characterized in that: the method comprises the following steps:

the fork truck has two states when potential energy is retrieved:

when the lifting oil cylinder is driven to drive a heavy object to be lowered, the three-position four-way electromagnetic reversing valve is located at the middle position, the inclined oil cylinder does not work, at the moment, the first two-position two-way electromagnetic reversing valve is electrified, the second two-position two-way electromagnetic reversing valve is not electrified, pressure oil in a second rodless cavity of the lifting oil cylinder flows into the hydraulic pump motor after passing through the first two-position two-way electromagnetic reversing valve, the throttle valve and the second one-way valve, the hydraulic pump motor 11 serves as a motor, the motor generator is in a power generation state, and electric energy is stored in the storage battery through the motor controller; due to the existence of the hydraulic pump motor, the pressure difference between two ends of the throttle valve can be adjusted, so that the accurate control of the descending speed is realized;

or,

when the lifting oil cylinder is driven to drive the heavy object to be lowered, the left position or the right position of the three-position four-way electromagnetic directional valve works, the inclined oil cylinder is in a working state, the working pressure of the inclined oil cylinder is lower than the pressure of a second rodless cavity of the lifting oil cylinder, the first two-position two-way electromagnetic directional valve and the second two-position two-way electromagnetic directional valve are electrified at the moment, and pressure oil in the second rodless cavity of the lifting oil cylinder flows into the first rodless cavity of the inclined oil cylinder after passing through the left positions or the right positions of the first two-position two-way electromagnetic directional valve, the second two-position two-way electromagnetic directional valve and the three-position four-way electromagnetic directional valve, so that the inclined oil cylinder drives the heavy object to be tilted forwards and backwards;

the energy release has two states:

when the lifting oil cylinder is driven to drive the fork to lift, the first two-position two-way electromagnetic reversing valve and the second two-position two-way electromagnetic reversing valve are electrified, energy stored in the storage battery is supplied to the motor generator to enable the motor generator to be in a motor state, the hydraulic pump motor is used as a hydraulic pump, the hydraulic pump outputs pressure oil outwards, the pressure oil enters the second rodless cavity of the lifting oil cylinder through the first one-way valve, the second two-position two-way electromagnetic reversing valve and the first two-position two-way electromagnetic reversing valve to push the lifting oil cylinder to drive the fork to complete lifting action, and recycling of recovered energy is achieved;

or,

when the driving tilting oil cylinder works and the lifting oil cylinder does not work, the first two-position two-way electromagnetic directional valve and the second two-position two-way electromagnetic directional valve are not electrified, the three-position four-way electromagnetic directional valve is electrified and works in the left position or the right position, at the moment, energy stored in the storage battery is supplied to the motor generator to enable the motor generator to be in a motor state, the hydraulic pump motor serves as a hydraulic pump, the hydraulic pump outputs pressure oil outwards, and the pressure oil output by the hydraulic pump flows into a first rodless cavity of the tilting oil cylinder after passing through the first one-way valve and the three-position four-way electromagnetic directional valve to enable the fork to be driven to incline forwards or backwards, so that the recycling of the energy is realized.

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