CN108560632B - An electro-hydraulic hybrid drive loader - Google Patents

Abstract

The invention discloses an electro-hydraulic hybrid-driven loader. The electro-hydraulic hybrid-driven loader adopts an electro-hydraulic mechanical cylinder or a hydraulic mechanical cylinder to replace the existing hydraulic cylinder, and adopts the hydraulic-electric hybrid drive mode without changing the loading. The mechanical structure of the machine has the advantages of precise control, high energy utilization rate, and can be applied to different tonnage models.

Description

An electro-hydraulic hybrid drive loader

technical field

The invention relates to the field of construction machinery, in particular to an electro-hydraulic hybrid drive loader.

Background technique

As a widely used construction machinery, loader has the advantages of fast operation speed, good maneuverability and simple operation. It is mainly used for shovel loading and transportation of soil, sand and gravel and other bulk materials. The traditional loader drive system mainly relies on the centralized oil supply of the hydraulic pump, adjusts the speed and pressure of each hydraulic cylinder by controlling the hydraulic valve, and then drives the working device to complete the corresponding action, there is a large throttling loss, and when the working device drops In addition, the current valve-controlled hydraulic cylinder system to obtain higher control accuracy will inevitably increase the complexity of the control system.

In order to solve this problem, patent CN 104632778A discloses a method: using a loader arm intelligent hydraulic cylinder, the piston rod drives the magnetic ring installed inside the piston rod to move on the waveguide during the movement process, and the generated signal is fed back to the On the controller, the hydraulic oil flowing into the cylinder is controlled by the hydraulic system to achieve the purpose of controlling the movement speed of the piston rod. This method increases the complexity of the hydraulic cylinder structure and increases the cost; the patent CN 103225321 discloses a method, which adopts the addition of an accumulator to recover the kinetic energy of the boom, but the power density of the accumulator is relatively low, and it takes up space Large, inconvenient to install, the effect is not obvious when the weight is large, and it is easy to cause structural fatigue.

SUMMARY OF THE INVENTION

Aiming at the shortcomings of the existing loader drive, the present invention proposes an electro-hydraulic hybrid drive loader. The electro-hydraulic hybrid drive loader uses an electro-hydraulic mechanical cylinder or a hydraulic mechanical cylinder to replace the existing hydraulic cylinder, and uses hydraulic The electric hybrid drive mode does not need to change the mechanical structure of the loader, has the advantages of precise control, high energy utilization, and can be applied to different tonnage models.

In order to achieve the above object, the present invention adopts the following technical solutions:

An electro-hydraulic hybrid drive loader, comprising a frame (30), wheels (31), a control system (32), a boom (33), a bucket (35), two travel motors (17) and a first A hydraulic drive circuit (1); wherein the wheels are driven by a travel motor;

It also includes three electro-hydraulic mechanical cylinders (15), and the electro-hydraulic mechanical cylinder further includes the first servo motor (18), the first variable pump/motor (19), the first transmission box (20) and the first lead screw (21). ), the output end of the first servo motor is connected in series with the input end of the first variable pump/motor, the output shaft of the first variable pump/motor is mechanically connected with the first gearbox, the first screw and the first gearbox are mechanically connected Connection; the boom is driven by 2 electro-hydraulic mechanical cylinders, and the bucket is driven by 1 electro-hydraulic mechanical cylinder;

The first hydraulic drive circuit (1) includes a power source (3), a constant pressure variable pump (4), a first filter (5), a fuel tank (6), a first relief valve (7), a first Check valve (8), pressure switching valve (9), second relief valve (10), first accumulator (11), second accumulator (12), third relief valve (13), pressure sensor (14), high pressure pipeline (28) and low pressure pipeline (29);

The power source is mechanically connected with the constant pressure variable pump, the oil suction port P of the constant pressure variable pump is connected with the oil tank through the first filter, and the oil outlet P of the constant pressure variable pump is connected with the oil inlet of the first check valve and the first one. The oil inlet of the relief valve is connected, the oil outlet of the first relief valve is connected with the oil tank, and the oil outlet of the first check valve is connected with the C port of the pressure switching valve, the pressure end of the pressure sensor and the high pressure oil circuit. , the oil outlet of the second overflow valve is connected to the oil tank; the electro-hydraulic mechanical cylinder and the traveling motor are connected in parallel between the high-pressure oil circuit and the low-pressure oil circuit, and the first working port A of the electro-hydraulic mechanical cylinder is connected to the high-pressure oil circuit. connected, the second working port T1 of the electro-hydraulic mechanical cylinder is connected with the low-pressure oil circuit, and finally connected with the oil tank;

The first working oil port C of the pressure switching valve is connected with the high pressure pipeline, the second working oil port D is connected with the oil outlet of the first accumulator and the oil inlet of the second relief valve, and the third working oil port is connected with the oil outlet of the first accumulator and the oil inlet of the second relief valve. The oil port E is communicated with the oil outlet of the second accumulator and the oil inlet of the third relief valve, and the oil outlet of the second relief valve and the third relief valve is respectively communicated with the oil tank.

An electro-hydraulic hybrid drive loader, comprising a frame (30), wheels (31), a control system (32), a boom (33), a bucket (35), two travel motors (17) and a second A hydraulic drive circuit (2); wherein the wheels are driven by a travel motor;

It also includes 3 hydraulic mechanical cylinders (16), and the hydraulic mechanical cylinder includes the second variable pump/motor (22), the second transmission box (23) and the second lead screw (24), and the output of the second variable pump/motor The end is connected in series with the input end of the second transmission box, and the second lead screw is mechanically connected with the second transmission box; the boom is driven by two hydraulic mechanical cylinders, and the bucket is driven by one hydraulic mechanical cylinder;

The second hydraulic drive circuit (2) includes a power source (3), a constant pressure variable pump (4), a first filter (5), a fuel tank (6), a first relief valve (7), a first One-way valve (8), second overflow valve (10), first accumulator (11), pressure sensor (14), high pressure pipeline (28) and low pressure pipeline (29);

The power source is mechanically connected with the constant pressure variable pump, the oil suction port of the constant pressure variable pump is connected to the oil tank through the first filter, and the oil outlet P of the constant pressure variable pump is connected with the oil inlet of the first check valve and the first overflow at the same time. The oil inlet of the flow valve is connected, the oil outlet of the first relief valve is connected with the oil tank, and the oil outlet of the first check valve is connected with the oil inlet of the second relief valve and the inlet of the first hydraulic accumulator at the same time. The oil port and the pressure end of the pressure sensor are connected to the high-pressure oil circuit, and the oil outlet of the second relief valve is connected to the oil tank; the hydraulic mechanical cylinder and the traveling motor are connected in parallel between the high-pressure oil circuit and the low-pressure oil circuit, and the above The first working port B of the hydraulic mechanical cylinder is connected with the high pressure oil circuit, and the second working port T2 of the hydraulic mechanical cylinder is connected with the low pressure oil circuit.

The first accumulator or the second accumulator is a hydraulic accumulator, or a hydraulic accumulator group composed of two or more hydraulic accumulators.

The first servo motor is an AC asynchronous motor, a switched reluctance motor or a DC motor.

The first servo motor and the first variable displacement pump/motor of the electro-hydraulic mechanical cylinder are mechanically connected.

The transmission case is a gear transmission case or a belt transmission case.

The electro-hydraulic mechanical cylinder and the hydraulic mechanical cylinder are driven by any form of a roller screw, a ball screw or a trapezoidal screw.

Compared with the prior art, an electro-hydraulic hybrid-driven loader of the present invention has the following advantages:

(1) The present invention uses a constant pressure variable pump and an accumulator to form a constant pressure network, and uses an electro-hydraulic mechanical cylinder to replace the original hydraulic cylinder, which can effectively recover the kinetic potential energy of the loader arm reciprocating rise and fall and the light shovel unloading of the bucket , and assist the drive in its ascent and acceleration stages, release energy at the same time, and improve energy utilization.

(2) The present invention combines the advantages of the secondary regulation circuit and the electric cylinder, and can control the rotational speed and torque by controlling the swing angle of the variable pump/motor. Compared with the valve control system, the valve control throttling loss is eliminated, and Convert control of linear motion to rotary motion control of hydraulic pumps/motors.

(3) The electro-hydraulic mechanical cylinder in the present invention retains the advantages of the electric cylinder, can achieve precise control, is suitable for use in heavy-load situations, and has a protective function; if the motor is removed, the hydraulic motor and the lead screw are mechanically connected , it will not affect its working performance, it can save space, improve its power-to-weight ratio, and realize the conversion from rotary motion to linear motion.

Description of drawings

Fig. 1 is the structure diagram of the loader of the present invention;

Fig. 2 is the structural diagram of the electro-hydraulic mechanical cylinder of the present invention;

Fig. 3 is the structure diagram of the hydraulic mechanical cylinder of the present invention;

4 is a schematic diagram of an electro-hydraulic hybrid drive loader using an electro-hydraulic mechanical cylinder according to the present invention;

Fig. 5 is the principle diagram of the electro-hydraulic hybrid drive loader adopting the hydraulic mechanical cylinder of the present invention;

6 is a schematic diagram of Embodiment 1 of the present invention;

FIG. 7 is a schematic diagram of Embodiment 2 of the present invention.

In the figure, 1-I hydraulic drive circuit, 2-I hydraulic drive circuit, 3-Power source, 4-Constant pressure variable pump, 5-I filter, 6-Oil tank, 7-I relief valve, 8-The first one-way valve, 9-pressure switching valve, 10-the second relief valve, 11-the first accumulator, 12-the second accumulator, 13-the third relief valve, 14-pressure sensor , 15-electro-hydraulic mechanical cylinder, 16-hydraulic mechanical cylinder, 17-travel motor, 18-first servo motor, 19-first variable pump/motor, 20-first gear box, 21-first lead screw, 22 - Ⅱ variable pump/motor, 23- Ⅱ transmission box, 24- Ⅱ lead screw, 25- Ⅱ check valve, 26- Ⅱ filter, 27- Ⅲ check valve, 28- high pressure oil circuit , 29- low pressure oil circuit, 30- frame, 31- wheel, 32- control system, 33- boom, 34- rocker arm, 35- bucket.

Detailed ways

As shown in FIG. 1, an electro-hydraulic hybrid drive loader includes a frame 30, wheels 31, a control system 32, a boom 33, a bucket 35, two travel motors 17 and a first hydraulic drive circuit 1; wherein , the wheels are driven by the travel motor.

Also includes 3 electro-hydraulic mechanical cylinders 15, as shown in Figure 2, the electro-hydraulic mechanical cylinder further includes the first servo motor 18, the first variable pump/motor 19, the first transmission box 20 and the first screw 21, the first The output end of the servo motor is connected in series with the input end of the first variable pump/motor, the output shaft of the first variable pump/motor is mechanically connected with the first transmission box, and the first lead screw and the first transmission box are mechanically connected; the boom It is driven by 2 electro-hydraulic mechanical cylinders, and the bucket is driven by 1 electro-hydraulic mechanical cylinder.

As shown in Figure 4, the first hydraulic drive circuit 1 includes a power source 3, a constant pressure variable pump 4, a first filter 5, a fuel tank 6, a first relief valve 7, a first one-way valve 8, a pressure The switching valve 9 , the second relief valve 10 , the first accumulator 11 , the second accumulator 12 , the third relief valve 13 , the pressure sensor 14 , the high pressure pipeline 28 and the low pressure pipeline 29 .

The power source is mechanically connected with the constant pressure variable pump, the oil suction port P of the constant pressure variable pump is connected with the oil tank through the first filter, and the oil outlet P of the constant pressure variable pump is connected with the oil inlet of the first check valve and the first one. The oil inlet of the relief valve is connected, the oil outlet of the first relief valve is connected with the oil tank, and the oil outlet of the first check valve is connected with the C port of the pressure switching valve, the pressure end of the pressure sensor and the high pressure oil circuit. , the oil outlet of the second overflow valve is connected to the oil tank; the electro-hydraulic mechanical cylinder and the traveling motor are connected in parallel between the high-pressure oil circuit and the low-pressure oil circuit, and the first working port A of the electro-hydraulic mechanical cylinder is connected to the high-pressure oil circuit. The second working port T1 of the electro-hydraulic mechanical cylinder is connected with the low-pressure oil circuit, and finally connected with the oil tank.

The first working oil port C of the pressure switching valve is connected with the high pressure pipeline, the second working oil port D is connected with the oil outlet of the first accumulator and the oil inlet of the second relief valve, and the third working oil port is connected with the oil outlet of the first accumulator and the oil inlet of the second relief valve. The oil port E is communicated with the oil outlet of the second accumulator and the oil inlet of the third relief valve, and the oil outlet of the second relief valve and the third relief valve is respectively communicated with the oil tank.

As shown in FIG. 1, an electro-hydraulic hybrid drive loader includes a frame 30, wheels 31, a control system 32, a boom 33, a bucket 35, two travel motors 17 and a second hydraulic drive circuit 2; wherein , the wheels are driven by the travel motor.

As shown in FIG. 3, it also includes three hydraulic mechanical cylinders 16, and the hydraulic mechanical cylinder includes the second variable pump/motor 22, the second transmission box 23 and the second lead screw 24. The output end of the second variable pump/motor is connected to the second variable pump/motor 22. The input ends of the second transmission box are connected in series, and the second lead screw and the second transmission box are mechanically connected; the boom is driven by two hydraulic mechanical cylinders, and the bucket is driven by one hydraulic mechanical cylinder.

As shown in FIG. 5, the second hydraulic drive circuit 2 includes a power source 3, a constant pressure variable pump 4, a first filter 5, a fuel tank 6, a first relief valve 7, a first one-way valve 8, a first II relief valve 10 , first accumulator 11 , pressure sensor 14 , high pressure pipeline 28 and low pressure pipeline 29 .

The power source is mechanically connected with the constant pressure variable pump, the oil suction port of the constant pressure variable pump is connected to the oil tank through the first filter, and the oil outlet P of the constant pressure variable pump is connected with the oil inlet of the first check valve and the first overflow at the same time. The oil inlet of the flow valve is connected, the oil outlet of the first relief valve is connected with the oil tank, and the oil outlet of the first check valve is connected with the oil inlet of the second relief valve and the inlet of the first hydraulic accumulator at the same time. The oil port and the pressure end of the pressure sensor are connected to the high-pressure oil circuit, and the oil outlet of the second relief valve is connected to the oil tank; the hydraulic mechanical cylinder and the traveling motor are connected in parallel between the high-pressure oil circuit and the low-pressure oil circuit, and the above The first working port B of the hydraulic mechanical cylinder is connected with the high pressure oil circuit, and the second working port T2 of the hydraulic mechanical cylinder is connected with the low pressure oil circuit.

The first accumulator or the second accumulator is a hydraulic accumulator, or a hydraulic accumulator group composed of two or more hydraulic accumulators.

The first servo motor is an AC asynchronous motor, a switched reluctance motor or a DC motor.

The first servo motor and the first variable displacement pump/motor of the electro-hydraulic mechanical cylinder are mechanically connected.

The transmission case is a gear transmission case or a belt transmission case.

The electro-hydraulic mechanical cylinder is driven by any form of roller screw, ball screw or trapezoidal screw.

Example 1

As shown in FIG. 1, an electro-hydraulic hybrid drive loader includes a frame 30, wheels 31, a control system 32, a boom 33, a bucket 35, two travel motors 17 and a first hydraulic drive circuit 1; wherein , the wheels are driven by the travel motor.

It also includes three hydraulic mechanical cylinders 16, as shown in Figure 3, the hydraulic mechanical cylinder includes the second variable pump/motor 22, the second transmission box 23 and the second lead screw 24. The output end of the second variable pump/motor is connected to the second variable pump/motor 22. The input ends of the second transmission box are connected in series, and the second lead screw and the second transmission box are mechanically connected; the boom is driven by two hydraulic mechanical cylinders, and the bucket is driven by one hydraulic mechanical cylinder.

As shown in FIG. 6, the first hydraulic drive circuit 1 includes a power source 3, a constant pressure variable pump 4, a first filter 5, a fuel tank 6, a first relief valve 7, a first one-way valve 8, a pressure The switching valve 9 , the second relief valve 10 , the first accumulator 11 , the second accumulator 12 , the third relief valve 13 , the pressure sensor 14 , the high pressure pipeline 28 and the low pressure pipeline 29 .

The power source is mechanically connected with the constant pressure variable pump, the oil suction port P of the constant pressure variable pump is connected with the oil tank through the first filter, and the oil outlet P of the constant pressure variable pump is connected with the oil inlet of the first check valve and the first one. The oil inlet of the relief valve is connected, the oil outlet of the first relief valve is connected with the oil tank, and the oil outlet of the first check valve is connected with the C port of the pressure switching valve, the pressure end of the pressure sensor and the high pressure oil circuit. , the oil outlet of the second overflow valve is connected to the oil tank; the hydraulic mechanical cylinder and the traveling motor are connected in parallel between the high-pressure oil circuit and the low-pressure oil circuit, and the first working port B of the hydraulic mechanical cylinder is connected to the high-pressure oil circuit, The second working port T2 of the hydraulic mechanical cylinder is connected with the low-pressure oil circuit, and finally connected with the oil tank.

The first working oil port C of the pressure switching valve is connected with the high pressure pipeline, the second working oil port D is connected with the oil outlet of the first accumulator and the oil inlet of the second relief valve, and the third working oil port is connected with the oil outlet of the first accumulator and the oil inlet of the second relief valve. The oil port E is communicated with the oil outlet of the second accumulator and the oil inlet of the third relief valve, and the oil outlet of the second relief valve and the third relief valve is respectively communicated with the oil tank.

Example 2

As shown in FIG. 1, an electro-hydraulic hybrid drive loader includes a frame 30, wheels 31, a control system 32, a boom 33, a bucket 35, two travel motors 17 and a second hydraulic drive circuit 2; wherein , the wheels are driven by the travel motor.

It also includes 3 electro-hydraulic mechanical cylinders 15, as shown in Figure 2, the electro-hydraulic mechanical cylinder also includes the first variable pump/motor 19, the first servo motor 18, the first transmission box 20 and the first lead screw 21, the first The output end of the servo motor is connected in series with the input end of the first variable pump/motor, the output shaft of the first variable pump/motor is mechanically connected with the first transmission box, and the first lead screw and the first transmission box are mechanically connected; the boom It is driven by 2 electro-hydraulic mechanical cylinders, and the bucket is driven by 1 electro-hydraulic mechanical cylinder.

As shown in FIG. 7, the second hydraulic drive circuit 2 includes a power source 3, a constant pressure variable pump 4, a first filter 5, a fuel tank 6, a first relief valve 7, a first one-way valve 8, a first II relief valve 10 , first accumulator 11 , pressure sensor 14 , high pressure pipeline 28 and low pressure pipeline 29 .

The power source is mechanically connected with the constant pressure variable pump, the oil suction port of the constant pressure variable pump is connected to the oil tank through the first filter, and the oil outlet P of the constant pressure variable pump is connected with the oil inlet of the first check valve and the first overflow at the same time. The oil inlet of the flow valve is connected, the oil outlet of the first relief valve is connected with the oil tank, and the oil outlet of the first check valve is connected with the oil inlet of the second relief valve and the inlet of the first hydraulic accumulator at the same time. The oil port and the pressure end of the pressure sensor are connected with the high-pressure oil circuit, and the oil outlet of the second relief valve is connected with the oil tank; the electro-hydraulic mechanical cylinder and the traveling motor are connected in parallel between the high-pressure oil circuit and the low-pressure oil circuit, The first working port A of the electro-hydraulic mechanical cylinder is connected to the high-pressure oil circuit, and the second working port T1 of the electro-hydraulic mechanical cylinder is connected to the low-pressure oil circuit.

Claims (7)

1. An electro-hydraulic hybrid driven loader comprises a frame (30), wheels (31), a control system (32), a movable arm (33), a bucket (35), two traveling motors (17) and a first hydraulic driving loop (1); wherein the wheels are driven by a walking motor;

the hydraulic control system is characterized by further comprising 3 electro-hydraulic mechanical cylinders (15), wherein each electro-hydraulic mechanical cylinder comprises an I-th servo motor (18), an I-th variable pump/motor (19), an I-th transmission case (20) and an I-th lead screw (21), the output end of the I-th servo motor is connected with the input end of the I-th variable pump/motor in series, the output shaft of the I-th variable pump/motor is mechanically connected with the I-th transmission case, and the I-th lead screw is mechanically connected with the I-th transmission case; the movable arm is driven by 2 electro-hydraulic mechanical cylinders, and the bucket is driven by 1 electro-hydraulic mechanical cylinder;

the first hydraulic driving circuit (1) comprises a power source (3), a constant-pressure variable pump (4), a first filter (5), an oil tank (6), a first overflow valve (7), a first one-way valve (8), a pressure switching valve (9), a second overflow valve (10), a first energy accumulator (11), a second energy accumulator (12), a third overflow valve (13), a pressure sensor (14), a high-pressure pipeline (28) and a low-pressure pipeline (29);

the power source is mechanically connected with the constant-pressure variable pump, an oil suction port P of the constant-pressure variable pump is communicated with the oil tank through a first filter, an oil outlet P of the constant-pressure variable pump is simultaneously connected with an oil inlet of a first check valve and an oil inlet of a first overflow valve, an oil outlet of the first overflow valve is communicated with the oil tank, an oil outlet of the first check valve is simultaneously connected with a port C of the pressure switching valve, a pressure end of the pressure sensor and the high-pressure oil way, and an oil outlet of a second overflow valve is connected with the oil tank; the electro-hydraulic mechanical cylinder and the walking motor are connected in parallel between a high-pressure oil way and a low-pressure oil way, a first working port A of the electro-hydraulic mechanical cylinder is connected with the high-pressure oil way, and a second working port T1 of the electro-hydraulic mechanical cylinder is connected with the low-pressure oil way and is finally communicated with an oil tank;

the oil outlet of the second working oil port E is communicated with the oil outlet of the second energy accumulator and the oil inlet of the third overflow valve, and the oil outlets of the third overflow valve and the fourth overflow valve are respectively communicated with the oil tank.

2. An electro-hydraulic hybrid driven loader comprises a frame (30), wheels (31), a control system (32), a movable arm (33), a bucket (35), two traveling motors (17) and a second hydraulic drive circuit (2); wherein the wheels are driven by a walking motor; the method is characterized in that:

the hydraulic mechanical cylinder comprises a second variable pump/motor (22), a second transmission case (23) and a second lead screw (24), wherein the output end of the second variable pump/motor is connected with the input end of the second transmission case in series, and the second lead screw is mechanically connected with the second transmission case; the movable arm is driven by 2 hydraulic mechanical cylinders, and the bucket is driven by 1 hydraulic mechanical cylinder;

the second hydraulic driving circuit (2) comprises a power source (3), a constant-pressure variable pump (4), a first filter (5), an oil tank (6), a first overflow valve (7), a first one-way valve (8), a second overflow valve (10), a first energy accumulator (11), a pressure sensor (14), a high-pressure pipeline (28) and a low-pressure pipeline (29);

the power source is mechanically connected with the constant-pressure variable pump, an oil suction port of the constant-pressure variable pump is communicated with an oil tank through a first filter, an oil outlet P of the constant-pressure variable pump is simultaneously connected with an oil inlet of a first check valve and an oil inlet of a first overflow valve, an oil outlet of the first overflow valve is communicated with the oil tank, an oil outlet of the first check valve is simultaneously communicated with an oil inlet of a second overflow valve, an oil inlet of a first hydraulic accumulator, a pressure end of a pressure sensor and a high-pressure oil way, and an oil outlet of the second overflow valve is connected with the oil tank; the hydraulic mechanical cylinder and the walking motor are connected in parallel between a high-pressure oil path and a low-pressure oil path, the I working port B of the hydraulic mechanical cylinder is connected with the high-pressure oil path, and the II working port T2 of the hydraulic mechanical cylinder is connected with the low-pressure oil path.

3. An electro-hydraulic hybrid drive loader according to claim 1 or 2, characterized in that: the first accumulator or the second accumulator is a hydraulic accumulator or a hydraulic accumulator group consisting of more than two hydraulic accumulators.

4. An electro-hydraulic hybrid drive loader according to claim 1 or 2, characterized in that: the first servo motor is an alternating current asynchronous motor, a switched reluctance motor or a direct current motor.

5. An electro-hydraulic hybrid drive loader according to claim 1 or 2, characterized in that: and the I servo motor of the electro-hydraulic mechanical cylinder is mechanically connected with the I variable pump/motor.

6. An electro-hydraulic hybrid drive loader according to claim 1 or 2, characterized in that: the transmission case is a gear transmission case or a belt transmission case.

7. An electro-hydraulic hybrid drive loader according to claim 1 or 2, characterized in that: the electro-hydraulic mechanical cylinder adopts any one form of a roller screw, a ball screw or a trapezoidal screw for transmission.

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