JP2021026348A - Work vehicle - Google Patents

Abstract

To provide a work vehicle which suppresses deterioration in accuracy of obstacle detection.SOLUTION: A work vehicle includes: a traveling vehicle body; a rear sensor 22 which is provided at a rear part of the traveling vehicle body so as to detect an obstacle behind the traveling vehicle body and which can change an inclination angle of a detection region extending posterior to the traveling vehicle body; and a controller 40 for changing the inclination angle of the detection region according to the type of a work machine W mounted at the rear part of the traveling vehicle body in an elevatable manner.SELECTED DRAWING: Figure 2

Description

The present invention relates to a work vehicle.

Conventionally, some work vehicles are equipped with a positioning device on a traveling vehicle body and autonomously travel while measuring the position of the traveling vehicle body. Such a work vehicle is equipped with a sensor that detects obstacles around the machine body, and by increasing the sensitivity inside the predetermined work area and decreasing the sensitivity outside the work area, objects that are not involved in the work can be regarded as obstacles. There is something that prevents detection (that is, false positive) (see, for example, Patent Document 1).

JP 2015-191592

By the way, in a work vehicle such as an agricultural tractor, a work machine that can be raised and lowered may be attached to the rear part of the traveling vehicle body. There are multiple types of work machines, which are replaced according to the work content. In the conventional work vehicle as described above, the work machine may enter the detection area of the sensor that detects an obstacle behind the machine, and the work machine may be erroneously detected as an obstacle, resulting in a decrease in obstacle detection accuracy. ..

The present invention has been made in view of the above, and an object of the present invention is to provide a work vehicle capable of suppressing a decrease in obstacle detection accuracy.

In order to solve the above-mentioned problems and achieve the object, the work vehicle (1) according to one aspect of the embodiment is provided at the traveling vehicle body (2) and the rear part of the traveling vehicle body (2), and the traveling vehicle body is provided. A rear sensor (22) that can detect an obstacle behind the traveling vehicle body (2) and can change the inclination angle of the detection region extending to the rear of the traveling vehicle body (2), and can move up and down to the rear part of the traveling vehicle body (2). It is characterized by including a control device (40) that changes the inclination angle of the detection region according to the type of the work machine (W) to be mounted.

According to one aspect of the embodiment, it is possible to suppress a decrease in obstacle detection accuracy.

FIG. 1 is an explanatory view of a work vehicle according to an embodiment. FIG. 2 is a block diagram showing an example of a control system including obstacle detection. FIG. 3 is a flowchart illustrating the inclination angle changing process according to the embodiment.

Hereinafter, embodiments of the work vehicle disclosed in the present application will be described in detail with reference to the accompanying drawings. The present invention is not limited to the embodiments shown below.

First, the overall configuration of the work vehicle 1 according to the embodiment will be described with reference to FIG. FIG. 1 is an explanatory view of the work vehicle 1 according to the embodiment, and is a schematic left side view of the work vehicle 1. In the following, a tractor will be described as an example of the work vehicle 1.

The tractor 1 which is a work vehicle is an agricultural tractor that performs work in a field or the like while traveling by itself. Further, the tractor 1 is provided by a control system centered on a control device 40 (see FIG. 2), which will be described later, in addition to executing a predetermined work while the operator (also referred to as an operator) is on board and traveling in the field. By controlling each part, a predetermined work is executed while automatically traveling in the field.

Further, in the following, the front-rear direction is defined as the traveling direction when the tractor 1 travels straight, and the front side of the traveling direction is defined as "front" and the rear side is defined as "rear". The traveling direction of the tractor 1 is a direction from the driver's seat 8 to the steering wheel 9, which will be described later, when traveling straight.

The left-right direction is a direction that is horizontally orthogonal to the front-back direction. In the following, the left and right are defined toward the "front" side. That is, with the operator of the tractor 1 seated in the driver's seat 8 and facing forward, the left hand side is "left" and the right hand side is "right".

The vertical direction is a direction parallel to the vertical direction. The front-back direction, the left-right direction, and the up-down direction are orthogonal to each other. It should be noted that each direction is defined for convenience of explanation, and the present invention is not limited to these directions. Further, in the following, the tractor 1 may be referred to as an "airframe".

As shown in FIG. 1, the tractor 1 includes a traveling vehicle body 2 and a working machine W. The traveling vehicle body 2 includes a vehicle body frame 3, front wheels 4, rear wheels 5, a bonnet 6, an engine E, a control unit 7, and a mission case 10. The body frame 3 is the main frame of the traveling vehicle body 2.

The front wheels 4 are a pair of left and right wheels, and are mainly steering wheels (steering wheels). The rear wheels 5 are a pair of left and right wheels, and are mainly driving wheels (driving wheels). The tractor 1 may be configured to be switchable between a two-wheel drive (2WD) driven by the rear wheels 5 and a four-wheel drive (4WD) driven by both the front wheels 4 and the rear wheels 5. In this case, the drive wheels are both the front wheels 4 and the rear wheels 5. The traveling vehicle body 2 may be provided with a crawler device instead of the wheels (front wheels 4 and rear wheels 5). In this case, the traveling crawler is the drive wheel.

The bonnet 6 is provided so as to be openable and closable at the front portion of the traveling vehicle body 2. The bonnet 6 can be rotated (opened and closed) in the vertical direction with the rear portion as the center of rotation. The bonnet 6 covers the engine E mounted on the vehicle body frame 3 in a closed state. The engine E is a drive source for the tractor 1 and is a heat engine such as a diesel engine or a gasoline engine.

The control unit 7 is provided on the upper part of the traveling vehicle body 2, and includes a driver's seat 8 and a steering wheel 9. The control unit 7 may be formed by being covered with a cabin 7a provided on the upper part of the traveling vehicle body 2. The driver's seat 8 is the driver's seat. The steering wheel 9 is operated by the operator when steering the front wheels 4, which are the steering wheels. The steering unit 7 is provided with a display unit (meter panel) for displaying various information in front of the steering wheel 9.

Further, the control unit 7 includes various operation levers such as a forward / backward forward lever, an accelerator lever, a main shift lever, and an auxiliary shift lever, and various operation pedals such as an accelerator pedal, a brake pedal, and a clutch pedal.

The transmission case 10 houses a transmission (transmission mechanism). The transmission appropriately decelerates the power (rotational power) transmitted from the engine E and transmits it to the rear wheels 5 which are the driving wheels and the PTO (Power Take-off) shaft.

A work machine W that performs work in the field is connected to the rear portion of the traveling vehicle body 2, and a PTO shaft that transmits power for driving the work machine W projects rearward from the mission case 10. The PTO shaft transmits the rotational power appropriately decelerated by the transmission to the working machine W mounted at least at the rear of the traveling vehicle body 2.

Further, an elevating device 12 for raising and lowering the working machine W is provided at the rear portion of the traveling vehicle body 2. The elevating device 12 moves the working machine W to a non-working position by raising the working machine W. The non-working position is, for example, a position where the working machine W is raised when the traveling vehicle body 2 retracts or when the traveling vehicle body 2 turns. Further, the elevating device 12 moves the work machine W to the ground work position by lowering the work machine W. The lifting device 12 includes a hydraulic lifting cylinder 121, a lift arm 122, a lift rod 123, a lower link 124, and a top link 125.

When the hydraulic oil is supplied to the elevating cylinder 121, the lift arm 122 rotates so as to raise the work machine W around the shaft AX which is a rotation fulcrum, and when the hydraulic oil is discharged from the elevating cylinder 121, the lift arm 122 rotates. The work machine W is rotated around the shaft AX so as to be lowered. A lift arm sensor 26 for detecting the rotation angle of the lift arm 122 is provided at the base of the lift arm 122 (near the shaft AX). The height of the working machine W is calculated based on the detection result of the lift arm sensor 26 and the working machine W.

Further, the lift arm 122 is connected to the lower link 124 via the lift rod 123. In this way, the elevating device 12 connects the working machine W to the traveling vehicle body 2 so as to be able to move up and down by the lower link 124 and the top link 125.

The working machine W is a machine that performs work in the field. In the example shown in FIG. 1, the working machine W is a rotary cultivator that performs cultivating work in a field. The rotary cultivator cultivates the field scene (soil) by rotating the cultivator 61 by the power transmitted from the PTO axis.

Further, the tractor 1 includes a control device 40 (see FIG. 2). The control device 40 controls the engine E and also controls the traveling speed of the traveling vehicle body 2. Further, the control device 40 controls the working machine W.

Further, the tractor 1 includes a positioning device 30. The positioning device 30 is provided on the upper part of the traveling vehicle body 2 and measures the position of the traveling vehicle body 2. The positioning device 30 is, for example, a GNSS (Global Navigation Satellite System), and can receive radio waves from a navigation satellite S orbiting in the sky to perform positioning and timing.

Further, the tractor 1 can set various operations in a specific field by operating the information processing terminal (portable terminal such as a tablet terminal) 100 by an operator. The information processing terminal 100 includes, for example, a storage unit composed of a hard disk, a ROM (Read Only Memory), a RAM (Random Access Memory), and a display unit and an operation unit composed of a touch panel. In addition, various keys, buttons, and the like may be separately provided as the operation unit.

Further, the tractor 1 includes an obstacle sensor 20. The obstacle sensor 20 includes a front sensor 21 and a rear sensor 22. The front sensor 21 is arranged at the front portion of the traveling vehicle body 2, such as being attached to a sensor mounting stay 13 provided in front of the bonnet 6, and is an obstacle (person or object) existing in front of the traveling vehicle body 2. Is detected.

The rear sensor 22 is arranged on the upper rear side of the traveling vehicle body 2, such as being attached to the upper portion of the cabin 7a, and detects an obstacle existing behind the traveling vehicle body 2. The rear sensor 22 can change the angle with respect to the cabin 7a, that is, the traveling vehicle body 2 by the motor 70 (see FIG. 2).

Further, both the front sensor 21 and the rear sensor 22 are medium-range sensors, preferably infrared sensors. The front sensor 21 and the rear sensor 22 emit an infrared beam and detect the reflected light from an obstacle. The front sensor 21 has a detection area extending forward. Further, the rear sensor 22 has a detection region extending rearward.

The front sensor 21 and the rear sensor 22 can detect the distance to the obstacle by, for example, measuring the time from emitting the infrared beam to detecting the reflected light from the obstacle. The front sensor 21 and the rear sensor 22, which are infrared sensors, detect obstacles two-dimensionally, and are, for example, a detection area of about several meters to several tens of meters. It is also possible to use a medium-range sensor other than the infrared sensor as the obstacle sensor 20.

Next, the control system of the work vehicle (tractor) 1 centering on the control device 40 will be described with reference to FIG. FIG. 2 is a block diagram showing an example of a control system including obstacle detection. As shown in FIG. 2, the control device 40 includes an engine ECU (Electronic Control Unit) 41, a traveling system ECU 42, and a work equipment elevating system ECU 43. The engine ECU 41 controls the rotation speed of the engine E. The traveling system ECU 42 controls the traveling speed of the traveling vehicle body 2 (see FIG. 1) by controlling the rotation of the drive wheels. The work equipment elevating system ECU 43 controls the elevating device 12 to elevate and control the work equipment W.

The control device 40 can control each part by electronic control, and includes a processing unit having a CPU (Central Processing Unit) and the like, various programs, a planned traveling route of the traveling vehicle body 2 preset for each field, and the like. It is equipped with a storage unit for storing necessary data.

As shown in FIG. 2, the control device 40 includes a positioning device (GNSS) 30, an engine rotation sensor 23, a vehicle speed sensor 24, a turning angle sensor 25, an obstacle sensor 20 (front sensor 21 and rear sensor 22), and a lift arm. Various sensors such as the sensor 26 are connected. The engine rotation sensor 23 detects the rotation speed of the engine E. The vehicle speed sensor 24 detects the traveling speed (vehicle speed) of the traveling vehicle body 2 (see FIG. 1). The turning angle sensor 25 detects the turning angle of the front wheels 4 (see FIG. 1), which are the steering wheels. The turning angle sensor 25 detects the turning of the airframe.

The control device 40 includes position information of the traveling vehicle body 2 from the positioning device 30 in a field or the like, the rotation speed of the engine E from the engine rotation sensor 23, the traveling speed of the traveling vehicle body 2 from the vehicle speed sensor 24, and the turning angle sensor 25 to the front wheel 4. The cutting angle is entered respectively. When the tractor 1 is autonomously driven, the control device 40 uses the detection result of the steering angle sensor 25 to control the steering cylinder connected to the steering wheel 9 while feeding back the steering angle of the front wheels 4, thereby controlling the steering wheel. 9 is automatically steered.

Further, in the control device 40, the engine ECU 41 is connected to the engine E, the traveling system ECU 42 is connected to the steering device 51, the transmission device 52, the braking device 53, and the like, and the work equipment elevating system ECU 43 is the elevating device 12 and the motor 70. Connected to.

Of these, the work equipment elevating system ECU 43 outputs a work equipment elevating signal to the elevating device 12. The elevating device 12 elevates and drives the work machine W based on the work machine elevating signal output from the work machine elevating system ECU 43.

Further, the work equipment elevating system ECU 43 outputs a sensor angle change signal for changing the inclination angle of the detection region of the rear sensor 22 according to the type of the work equipment W. Specifically, the work equipment elevating system ECU 43 outputs a sensor angle change signal for changing the vertical tilt angle of the detection region of the rear sensor 22 (hereinafter, referred to as “tilt angle of the rear sensor 22”).

The motor 70 drives the rear sensor 22 so as to change the tilt angle of the rear sensor 22. Specifically, the motor 70 is driven based on the sensor angle change signal output from the work equipment elevating system ECU 43, changes the mounting angle of the rear sensor 22 with respect to the traveling vehicle body 2, and changes the tilt angle of the rear sensor 22. To do. When viewed from the side, the inclination angle is formed below the rear sensor 22 in the area sandwiched between the rear sensor 22 and the vertical virtual line passing through the mounting position of the rear sensor 22. Angle. Further, the tilt angle of the rear sensor 22 is set so that the lower limit range on the lower side of the detection region of the rear sensor 22 does not overlap with the working machine W.

The driving of the motor 70 is not limited to the working machine elevating system ECU 43, and may be performed by another ECU. Further, the motor 70 is built in the rear sensor 22, and may change the radiation direction of the infrared beam, for example.

In addition, the control device 40 has an "automatic operation mode" in which the tractor 1 performs work while autonomously traveling. In the automatic operation mode, the control device 40 determines in advance a planned travel route according to the work content of the work machine W for each field, converts it into data and stores it in the storage unit, and based on the measurement result of the positioning device 30. , Each part such as the engine E, the steering device 51, the transmission 52, the braking device 53, and the elevating device 12 is controlled so as to travel along the stored scheduled traveling path. The planned travel route is set according to the shape and size of the field, the width, length and number of ridges formed in the field, the type of crop, and the like.

Further, the control device 40 is wirelessly connected to, for example, an information processing terminal 100 that can be carried by an operator. The control device 40 controls each part of the tractor 1 based on an instruction signal from the information processing terminal 100 operated by the operator. Further, the control device 40 may be configured to hold the aircraft information database of the tractor 1 so that information such as a model can be exchanged from the information processing terminal 100 or the like.

Further, the control device 40 stops the traveling vehicle body 2 when an obstacle is detected by the front sensor 21 or the rear sensor 22. Further, when an obstacle is detected by the front sensor 21 or the rear sensor 22, the control device 40 stops the engine E or stops the transmission of the rotational power to the PTO shaft. Further, the control device 40 activates an alarm device (not shown) when an obstacle is detected by the front sensor 21 or the rear sensor 22, and the control device 40 detects the obstacle. It may be notified.

Next, the tilt angle of the rear sensor 22 will be described.

The length of the work machine W in the front-rear direction is different for each type. Therefore, the control device 40 changes the tilt angle of the rear sensor 22 according to the type of the work machine W. By changing the tilt angle of the rear sensor 22, the range in which obstacles can be detected by the rear sensor 22 is changed.

When the length of the work machine W in the front-rear direction is a predetermined standard length, the tilt angle of the rear sensor 22 is set to a predetermined standard angle. Specifically, the control device 40 drives the motor 70 so that the tilt angle of the rear sensor 22 becomes a predetermined standard angle.

Further, when the length of the work machine W in the front-rear direction is longer than the predetermined standard length, the control device 40 changes the sensor angle so that the tilt angle of the rear sensor 22 becomes larger than the predetermined standard angle. Output a signal. That is, the control device 40 drives the motor 70 so that the detection range of the rear sensor 22 is higher than the detection range at a predetermined standard angle. The control device 40 may drive the motor 70 so that a part of the detection range of the rear sensor 22 is above the detection range at a predetermined standard angle.

Further, when the length of the work equipment W in the front-rear direction is shorter than the predetermined standard length, the control device 40 changes the sensor angle so that the tilt angle of the rear sensor 22 becomes smaller than the predetermined standard angle. Output a signal. That is, the control device 40 drives the motor 70 so that the detection range of the rear sensor 22 is lower than the detection range at a predetermined standard angle. The control device 40 may drive the motor 70 so that a part of the detection range of the rear sensor 22 is lower than the detection range at a predetermined standard angle.

The tilt angle of the rear sensor 22 is stored in the storage unit as, for example, a table associated with the type of the work machine W.

Therefore, when the type of the work machine W is identified based on the table or the like stored in the storage unit, the control device 40 sets the tilt angle of the rear sensor 22 according to the type of the work machine W. The change signal is output and the tilt angle of the rear sensor 22 is set. The type of the working machine W may be identified automatically by the control device 40, or may be identified based on the information input by the worker.

Next, the tilt angle changing process according to the embodiment will be described with reference to FIG. FIG. 3 is a flowchart illustrating the inclination angle changing process according to the embodiment.

The control device 40 identifies the type of the work machine W mounted on the traveling vehicle body 2 (S100). The control device 40 outputs a sensor angle change signal (S102) according to the type of the identified work machine W, drives the motor 70 based on the sensor angle change signal, and changes the tilt angle of the rear sensor 22. (S103).

Next, the effect of the tractor 1 according to the embodiment will be described.

The tractor 1 is provided at the rear of the traveling vehicle body 2, and has a rear sensor 22 for detecting an obstacle behind the traveling vehicle body 2 and a rear sensor 22 depending on the type of the work machine W mounted on the rear portion of the traveling vehicle body 2. A control device 40 for changing the inclination angle of the detection area is provided.

As a result, the tractor 1 can prevent the work machine W from being erroneously detected as an obstacle when detecting an obstacle behind the machine body. Therefore, the tractor 1 can suppress a decrease in obstacle detection accuracy due to the shape and size of the work machine W.

Further, the tractor 1 changes the tilt angle of the rear sensor 22 in the vertical direction according to the type of the work machine W.

As a result, the tractor 1 can suppress a decrease in obstacle detection accuracy due to the length of the work machine W in the front-rear direction.

Further, when the length of the work machine W attached to the traveling vehicle body 2 in the front-rear direction is longer than the standard length, the tractor 1 is attached to the traveling vehicle body 2 by changing the inclination angle of the rear sensor 22 upward. When the length of the working machine W in the front-rear direction is shorter than the standard length, the tilt angle of the rear sensor 22 is changed downward.

As a result, the tractor 1 sets the detection area so that the work machine W does not enter the detection area of the rear sensor 22 by increasing the inclination angle of the detection area of the rear sensor 22 when the work machine W is long in the front-rear direction. Therefore, it is possible to prevent the work machine W from being erroneously detected as an obstacle. Further, when the work machine W is short in the front-rear direction, the tractor 1 lowers the inclination angle of the detection area of the rear sensor 22 so that no obstacle is detected between the detection area of the rear sensor 22 and the work machine W. It is possible to prevent an undetected area from being generated.

Next, the tractor 1 according to the modified example will be described.

The tractor 1 according to the modified example may raise and lower the working machine W to set the tilt angle of the rear sensor 22 after the working machine W is mounted on the traveling vehicle body 2.

Specifically, after the working machine W is mounted on the traveling vehicle body 2, the control device 40 raises the working machine W to at least a non-working position. Then, the control device 40 detects the work machine W by the rear sensor 22 while driving the motor 70 to change the inclination angle of the rear sensor 22.

For example, the control device 40 changes the tilt angle of the rear sensor 22 from the lower side to the upper side while the work machine W is raised to the non-working position. Then, when the control device 40 stops detecting the work machine W by the rear sensor 22, the change of the tilt angle of the rear sensor 22 is completed, and the angle at which the work machine W is no longer detected is set as the tilt angle with respect to the work machine W. Set.

The control device 40 changes the tilt angle of the rear sensor 22 from above to downward in a state where the work machine W is raised to a non-working position, and when the rear sensor 22 detects the work machine W, the rear sensor 22 is used. The change of the inclination angle of 22 may be completed, and the angle may be set to the inclination angle with respect to the working machine W.

As a result, the tractor 1 according to the modified example can set the detection area by using the detection function of the rear sensor 22. Further, the tractor 1 according to the modified example automatically sets the detection area of the rear sensor 22 without storing the type of the work machine W and the inclination angle of the rear sensor 22 in the storage unit. Can be done. Therefore, the tractor 1 according to the modified example can automatically set the detection area of the rear sensor 22 even when the work machine W that is not stored in the storage unit is used.

Further, the tractor 1 according to the modified example has an inclination angle of the rear sensor 22 with respect to the working machine W, which is a boundary between whether or not to detect the working machine W in a state where the working machine W is raised to a non-working position. The angle deviated upward from the predetermined angle may be the tilt angle of the rear sensor 22 with respect to the work machine W.

As a result, the tractor 1 makes the detection area of the rear sensor 22 upward so as to have a margin, so that, for example, even if the work machine W bounces during work, the bounced work machine W is erroneously detected as an obstacle. Will not be.

Further, the tractor 1 according to the modified example may detect the remaining amount of fertilizer in the fertilizer tank of the fertilizer spraying device that sprays fertilizer in the field by the rear sensor 22. The fertilizer spraying device is mounted on the rear part of the traveling vehicle body 2 like the working machine W. That is, the fertilizer spraying device is included in the working machine W.

The tractor 1 according to the modified example is set so as not to detect an obstacle at a distance where the fertilizer spraying device is detected.

For example, the tractor 1 according to the modified example detects the remaining amount of fertilizer in the fertilizer tank, that is, the amount of fertilizer has decreased, based on the change in the reflected light at a distance where no obstacle is detected. The rear sensor 22 may be provided with a color identification function to detect that the amount of fertilizer has decreased from the change in color based on the change in the remaining amount of fertilizer in the fertilizer tank.

Further effects and variations can be easily derived by those skilled in the art. For this reason, the broader aspects of the invention are not limited to the particular details and representative embodiments expressed and described as described above. Therefore, various modifications can be made without departing from the spirit or scope of the general concept of the invention as defined by the appended claims and their equivalents.

1 Tractor (working vehicle)
2 Traveling vehicle body 12 Lifting device 22 Rear sensor 26 Lift arm sensor 40 Control device 70 Motor W Working machine

Claims (6)

With the running body
A rear sensor provided at the rear of the traveling vehicle body, which detects an obstacle behind the traveling vehicle body and can change the inclination angle of a detection region extending to the rear of the traveling vehicle body.
A work vehicle including a control device that changes the inclination angle of the detection region according to the type of work machine that is mounted on the rear portion of the traveling vehicle body so as to be able to move up and down. The working machine is
The length in the front-back direction is different for each type,
The control device is
The work vehicle according to claim 1, wherein the vertical inclination angle of the detection region is changed according to the type of the work machine. The control device is
When the length of the working machine in the front-rear direction is longer than the standard length, the inclination angle of the detection area of the rear sensor is changed upward.
The work vehicle according to claim 2, wherein when the length of the work machine in the front-rear direction is shorter than the standard length, the inclination angle of the detection region of the rear sensor is changed downward. A motor for driving the rear sensor to change the tilt angle of the detection area is provided.
The control device is
When the detection area is set after the work machine is mounted on the traveling vehicle body, the work machine is raised to at least a non-working position, and the tilt angle of the detection area is directed from above to below by the motor. The work vehicle according to claim 3, wherein the rear sensor is driven so as to be changed, and when the rear sensor detects the work machine, the drive of the rear sensor is stopped. A motor for driving the rear sensor to change the tilt angle of the detection area is provided.
The control device is
When the detection area is set after the work machine is mounted on the traveling vehicle body, the work machine is raised to at least a non-working position, and the tilt angle of the detection area is directed from the lower side to the upper side by the motor. The work vehicle according to claim 3, wherein the rear sensor is driven so as to be changed, and when the rear sensor stops detecting the work machine, the drive of the rear sensor is stopped. The control device is
The fourth or fifth aspect of the present invention, wherein when the detection area is set, the inclination angle of the detection area is shifted upward by a predetermined angle from an angle that is a boundary of whether or not to detect the work machine. Work vehicle.

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