Patent Description:
An operator who operates a shovel serving as a construction machine is required to have expert operational skills to efficiently and accurately perform work such as excavation with an attachment. That being so, a shovel that has a function of guiding shovel operations (hereinafter referred to as "machine guidance function") to allow less experienced shovel operators to accurately perform work is known. (See, for example, Patent Document <NUM>.

Japanese Patent Document <CIT> discloses a display system for a construction machine that can display the operation state of the construction machine at a plurality of display positions on transparent windows disposed around the operator's cab.

<CIT> discloses a construction machine control system that displays guiding information for guiding a working tool to a working position.

According to shovels with the machine guidance function, for example, information such as a working condition is displayed, on the screen of a display device installed diagonally in front of a driver's seat. A shovel operator can check the working condition of the shovel from the information displayed on the display device.

The display device is limited in size so as not to hinder the vision of the operator. Accordingly, because the screen of the display device is reduced in size, the operator may be unable to obtain desired information unless gazing at the screen of the display device.

Furthermore, shovel operators normally perform operations while watching the teeth tips of a bucket or an excavation site positioned in front of the driver's seat, and therefore cannot look at the display device for a long time during operations. Accordingly, shovel operators can look at the display device for an extremely short time during operations, and may have difficulty in checking desired information from an image displayed on the display device within the time.

The present invention has been made in view of the above, and has an object of providing a shovel that makes it possible to efficiently and accurately perform work while checking work information.

A shovel according to the present invention is defined in the independent claim and includes a traveling undercarriage configured to travel, an upper rotating structure swingably mounted on the traveling undercarriage, a cab mounted on the upper rotating structure, an attachment including a working part configured to perform work, and a display device provided in the cab, wherein the display device is configured to display an image including a work guidance display part, the work guidance display part showing an attitude of the working part and a work target surface, and the display device is configured to display a position indicator image in the work guidance display part such that the position indicator image is larger when the attachment is in operation than when the attachment is not in operation, the position indicator image showing a positional relationship between the working part and the target surface.

According to an embodiment of the present invention, a shovel that makes it possible to efficiently and accurately perform work while checking work information is provided.

Embodiments of the present invention are described below with reference to drawings. In the drawings, the same constituent parts are given the same reference character, and a repetitive description thereof may be omitted.

<FIG> is a side view illustrating a shovel according to an embodiment.

An upper rotating structure <NUM> is mounted on a traveling undercarriage <NUM> of the shovel via a swing mechanism <NUM>. A boom <NUM> is attached to the upper rotating structure <NUM>. An arm <NUM> is attached to an end of the boom <NUM>. A bucket <NUM> serving as an end attachment (a working part) is attached to an end of the arm <NUM>. A slope bucket, a dredging bucket, a breaker or the like may alternatively be attached as an end attachment.

The boom <NUM>, the arm <NUM>, and the bucket <NUM> form an excavation attachment as an example of an attachment, and are hydraulically driven by a boom cylinder <NUM>, an arm cylinder <NUM>, and a bucket cylinder <NUM>, respectively. A boom angle sensor S1 is attached to the boom <NUM>. An arm angle sensor S2 is attached to the arm <NUM>. A bucket angle sensor S3 is attached to the bucket <NUM>. A bucket tilt mechanism may be provided on the excavation attachment. The boom angle sensor S1, the arm angle sensor S2, and the bucket angle sensor S3 may be referred to as "attitude sensors.

The boom angle sensor S1 detects the rotation angle of the boom <NUM>. For example, the boom angle sensor S1 is an acceleration sensor that detects the rotation angle of the boom <NUM> relative to the upper rotating structure <NUM> by detecting an inclination to a horizontal plane.

The arm angle sensor S2 detects the rotation angle of the arm <NUM>. For example, the arm angle sensor S2 is an acceleration sensor that detects the rotation angle of the arm <NUM> relative to the boom <NUM> by detecting an inclination to a horizontal plane.

The bucket angle sensor S3 detects the rotation angle of the bucket <NUM>. For example, the bucket angle sensor S3 is an acceleration sensor that detects the rotation angle of the bucket <NUM> relative to the arm <NUM> by detecting an inclination to a horizontal plane.

When the excavation attachment is provided with a bucket tilt mechanism, the bucket angle sensor S3 additionally detects the rotation angle of the bucket <NUM> about a tilt axis. The boom angle sensor S1, the arm angle sensor S2, and the bucket angle sensor S3 may alternatively be potentiometers using a variable resistor, stroke sensors that detect the stroke amount of a corresponding hydraulic cylinder, or rotary encoders that detect a rotation angle about a connecting pin.

Power sources such as an engine <NUM> and a body tilt sensor S4 are mounted on the upper rotating structure <NUM> and covered with a cover 3a. The body tilt sensor S4 detects the tilt angle of the upper rotating structure <NUM>. For example, the body tilt sensor S4 is an acceleration sensor that detects the tilt angle of the upper rotating structure <NUM> by detecting an inclination to a horizontal plane.

An image capturing unit <NUM> is provided on top of the cover 3a. The image capturing unit <NUM> includes, facing a cabin <NUM> from the upper rotating structure <NUM>, a left-side camera <NUM> that captures an image on the left side, a right-side camera 80R that captures an image on the right side, and a back-side camera 80B that captures an image on the back side. The left-side camera <NUM>, the right-side camera 80R, and the back-side camera 80B are, for example, digital cameras that contain an imaging device such as a CCD or CMOS, and transmit respective captured images to a display device <NUM> provided in the cabin <NUM>.

The cabin <NUM>, serving as a cab, is provided on the upper rotating structure <NUM>. A GPS device (a GNSS receiver) G1 is provided on top of the cabin <NUM>. The GPS device G1 detects the position of the shovel using a GPS function, and feeds position data to a machine guidance device <NUM> in a controller <NUM>. The controller <NUM>, the display device <NUM>, an audio output device <NUM>, an input device <NUM>, and a storage device <NUM> are provided in the cabin <NUM>.

The controller <NUM> operates as a main control part to control the driving of the shovel. The controller <NUM> is composed of a processing unit including a CPU and an internal memory. The CPU executes a program stored in the internal memory to implement various functions of the controller <NUM>.

The controller <NUM> also operates as the machine guidance device <NUM> to guide shovel operations. For example, the machine guidance device <NUM> notifies an operator of work information such as the distance between a target surface that is the surface of a target terrain set by the operator and the working part of the attachment. The distance between the target surface and the working part of the attachment is, for example, the distance between the target surface and the end (teeth tips) of the bucket <NUM> as an end attachment, the back surface of the bucket <NUM>, the end of a breaker as an end attachment, or the like. The machine guidance device <NUM> notifies the operator of work information through the display device <NUM>, the audio output device <NUM>, etc., to guide shovel operations.

While the machine guidance device <NUM> is incorporated into the controller <NUM> according to this embodiment, the machine guidance device <NUM> and the controller <NUM> may alternatively be provided separately. In this case, like the controller <NUM>, the machine guidance device <NUM> is composed of a processing unit including a CPU and an internal memory. The CPU executes a program stored in the internal memory to implement various functions of the machine guidance device <NUM>.

The display device <NUM> displays an image including various kinds of work information in response to a command from the machine guidance device <NUM> included in the controller <NUM>. The display device <NUM> is, for example, an in-vehicle liquid crystal display connected to the machine guidance device <NUM>.

The audio output device <NUM> outputs various kinds of audio information in response to an audio output command from the machine guidance device <NUM> included in the controller <NUM>. The audio output device <NUM> includes, for example, an in-vehicle speaker connected to the machine guidance device <NUM>. The audio output device <NUM> may include an alarm such as a buzzer.

The input device <NUM> is a device for inputting various kinds of information to the controller <NUM> including the machine guidance device <NUM> by the operator of the shovel. The input device <NUM> includes, for example, a membrane switch provided on the surface of the display device <NUM>. The input device <NUM> may include a touchscreen or the like.

The storage device <NUM> is a device for storing various kinds of information. The storage device <NUM> is, for example, a non-volatile storage medium such as a semiconductor memory. The storage device <NUM> stores various kinds of information output by the controller <NUM> including the machine guidance device <NUM>, etc..

A gate lock lever <NUM> is a mechanism provided between the door and the driver's seat of the cabin <NUM> to prevent the shovel from being accidentally operated. When the operator climbs onto the driver's seat and pulls up the gate lock lever <NUM>, the operator is prevented from getting out of the cabin <NUM> and various operation apparatuses become operable. When the operator pushes down the gate lock lever <NUM>, the operator can get out of the cabin <NUM> and various operation apparatuses become inoperable.

<FIG> is a diagram illustrating a configuration of connections including the controller <NUM> of the shovel according to an embodiment.

The display device <NUM> is provided in the cabin <NUM> to display an image including work information fed from the machine guidance device <NUM>, etc. The display device <NUM> is connected to the controller <NUM> including the machine guidance device <NUM> via a communications network such as a Controller Area Network (CAN) or a Local Interconnect Network (LIN), a dedicated line, etc..

The display device <NUM> includes a conversion part 40a to generate an image to be displayed on an image display part <NUM>. The conversion part 40a generates an image including captured images to be displayed on the image display part <NUM>, based on image data obtained from the image capturing unit <NUM>. Image data are input to the display device <NUM> from each of the left-side camera <NUM>, the right-side camera 80R, and the back-side camera 80B.

Furthermore, the conversion part 40a converts, into an image signal, data to be displayed on the image display part <NUM> among various kinds of data input to the display device <NUM> from the controller <NUM>. The data input to the display device <NUM> from the controller <NUM> include, for example, data indicating the temperature of engine coolant water, data indicating the temperature of hydraulic oil, data indicating the remaining amount of an aqueous urea solution, data indicating the remaining amount of fuel, etc..

The conversion part 40a outputs image signals after conversion to the image display part <NUM> to display an image generated based on captured images and various kinds of data on the image display part <NUM>.

The conversion part 40a may be provided in not the display device <NUM> but, for example, the controller <NUM>. In this case, the image capturing unit <NUM> is connected to the controller <NUM>.

The display device <NUM> includes a switch panel <NUM> serving as an input part. The switch panel <NUM> is a panel including various kinds of hardware switches. The switch panel <NUM> includes a light switch 42a, a windshield wiper switch 42b, and a window washer switch 42c.

The light switch 42a is a switch for turning on and off lights attached to the exterior of the cabin <NUM>. The windshield wiper switch 42b is a switch for moving and stopping a windshield wiper. The window washer switch 42c is a switch for spraying window washer fluid.

The display device <NUM> is supplied with electric power from a rechargeable battery <NUM> to operate. The rechargeable battery <NUM> is charged with electric power generated in an alternator 11a (generator) of the engine <NUM>. The electric power of the rechargeable battery <NUM> is also supplied to electrical equipment <NUM>, etc., of the shovel besides the controller <NUM> and the display device <NUM>. Furthermore, a starter 11b of the engine <NUM> is driven with electric power from the rechargeable battery <NUM> to start the engine <NUM>.

The engine <NUM> is connected to a main pump <NUM> and a pilot pump <NUM>, and is controlled by an engine control unit (ECU) <NUM>. Various data indicating the condition of the engine <NUM> (for example, data indicating coolant water temperature (a physical quantity) detected with a water temperature sensor 11c, etc.) are constantly transmitted from the ECU <NUM> to the controller <NUM>. The controller <NUM> can store these data in an internal temporary storage part (memory) 30a and suitably transmit the data to the display device <NUM>.

The main pump <NUM> is a hydraulic pump for supplying hydraulic oil to a control valve <NUM> via a highpressure hydraulic line. The main pump <NUM> is, for example, a swash-plate variable displacement hydraulic pump.

The pilot pump <NUM> is a hydraulic pump for supplying hydraulic oil to various hydraulic control apparatuses via a pilot line. The pilot pump <NUM> is, for example, a fixed displacement hydraulic pump.

The control valve <NUM> is a hydraulic controller to control the hydraulic system of the shovel. For example, the control valve <NUM> selectively supplies hydraulic oil discharged by the main pump <NUM> to the boom cylinder <NUM>, the arm cylinder <NUM>, the bucket cylinder <NUM>, traveling hydraulic motors, a swing hydraulic motor, etc. In the following, the boom cylinder <NUM>, the arm cylinder <NUM>, the bucket cylinder <NUM>, the traveling hydraulic motors, and the swing hydraulic motor may be referred to as "hydraulic actuators.

Operation levers 26A through 26C are provided in the cabin <NUM> to be used by the operator to operate hydraulic actuators. When the operation levers 26A through 26C are operated, hydraulic oil is supplied from the pilot pump to the pilot ports of flow control valves corresponding to hydraulic actuators. Each pilot port is supplied with hydraulic oil of a pressure commensurate with the direction of operation and the amount of operation of a corresponding one of the operation levers 26A through 26C.

According to this embodiment, the operation lever 26A is a boom operation lever. The operator can hydraulically drive the boom cylinder <NUM> to operate the boom <NUM> when operating the operation lever 26A. The operation lever 26B is an arm operation lever. The operator can hydraulically drive the arm cylinder <NUM> to operate the arm <NUM> when operating the operation lever 26B. The operation lever 26C is a bucket operation lever. The operator can hydraulically drive the bucket cylinder <NUM> to operate the bucket <NUM> when operating the operation lever 26C. Besides the operation levers 26A through 26C, operation levers, operation pedals, etc., for driving the traveling hydraulic motors, the swing hydraulic motor, etc., may be provided in the shovel.

The controller <NUM> obtains, for example, various kinds of data described below. The data obtained by the controller <NUM> are stored in the temporary storage part 30a.

A regulator 14a of the main pump <NUM>, which is a variable displacement hydraulic pump, transmits data indicating a swash plate angle to the controller <NUM>. Furthermore, a discharge pressure sensor 14b transmits data indicating the discharge pressure of the main pump <NUM> to the controller <NUM>. These data (data representing physical quantities) are stored in the temporary storage part 30a. Furthermore, an oil temperature sensor 14c provided in a conduit between the main pump <NUM> and a tank storing hydraulic oil that the main pump <NUM> draws in transmits data representing the temperature of hydraulic oil flowing through the conduit to the controller <NUM>.

Pressure sensors 15a and 15b detect a pilot pressure transmitted to the control valve <NUM> when the operation levers 26A through 26C are operated, and transmit data indicating the detected pilot pressure to the controller <NUM>. The operation levers 26A through 26C are provided with a switch button <NUM>. The operator can transmit a command signal to the controller <NUM> by operating the switch button <NUM> while operating the operation levers 26A through 26C.

An engine rotational speed adjustment dial <NUM> is provided in the cabin <NUM>. The engine rotational speed adjustment dial <NUM> is a dial for adjusting the rotational speed of the engine <NUM>, and, for example, can switch the engine rotation speed in a stepwise manner. According to this embodiment, the engine rotational speed adjustment dial <NUM> is provided to make it possible to switch the engine rotational speed among the four levels of SP mode, H mode, A mode, and idling mode. The engine rotational speed adjustment dial <NUM> transmits data indicating the setting of the engine rotational speed to the controller <NUM>. <FIG> illustrates a state where the H mode is selected by the engine rotational speed adjustment dial <NUM>.

The SP mode is a rotational speed mode selected when it is desired to prioritize workload, and uses the highest engine rotational speed. The H mode is a rotational speed mode selected when it is desired to satisfy both workload and fuel efficiency, and uses the second highest engine rotational speed. The A mode is a rotational speed mode selected when it is desired to operate the shovel with low noise while prioritizing fuel efficiency, and uses the third highest engine rotational speed. The idling mode is a rotational speed mode selected when it is desired to idle the engine, and uses the lowest engine rotational speed. The engine <NUM> is controlled to a constant rotational speed at the engine rotational speed of the rotational speed mode set by the engine rotational speed adjustment dial <NUM>.

Next, various functions provided in the controller <NUM> and the machine guidance device <NUM> of the shovel are described. <FIG> is a diagram illustrating a configuration of the controller <NUM> and the machine guidance device <NUM> according to an embodiment.

The controller <NUM> controls the entire shovel including the engine controller <NUM>. The controller <NUM> performs control to close a gate lock valve 49a when the gate lock lever <NUM> is pushed down and to open the gate lock valve 49a when the gate lock lever <NUM> is pulled up. The gate lock valve 49a is a selector valve provided in an oil passage between the control valve <NUM> and the operation levers 26A through 26C, etc. Here, the gate lock valve 49a is configured to be opened or closed based on a command from the controller <NUM>. Alternatively, the gate lock valve 49a may be mechanically connected to the gate lock lever <NUM> to be opened or closed in response to the operation of the gate lock lever <NUM>.

The gate lock valve 49a is closed to interrupt a flow of hydraulic oil between the control valve <NUM> and the operation levers 26A through 26C, etc., to disable the operation levers 26A through 26C, etc. The gate lock valve 49a is opened to allow passage of hydraulic oil between the control valve <NUM> and the operation levers, etc., to enable the operation levers 26A through 26C, etc..

The controller <NUM> detects the amount of operation of each lever from a pilot pressure detected by the pressure sensor 15a or 15b with the gate lock valve 49a being opened to have the operation levers 26A through 26c enabled.

In addition to controlling the operation of the entire shovel, the controller <NUM> controls whether to give guidance by the machine guidance device <NUM>. Specifically, in response to determining that the shovel is not working, the controller <NUM> transmits a guidance stop command to the machine guidance device <NUM> to stop guidance by the machine guidance device <NUM>.

The controller <NUM> may output a guidance stop command to the machine guidance device <NUM> when outputting an automatic idling stop command to the engine controller <NUM>. Alternatively, the controller <NUM> may output a guidance stop command to the machine guidance device <NUM> in response to determining that the gate lock lever <NUM> is pushed down.

Next, the machine guidance device <NUM> is described. The machine guidance device <NUM> receives various signals and data supplied to the controller <NUM>, from the boom angle sensor S1, the arm angle sensor S2, the bucket angle sensor S3, the body tilt sensor S4, the GPS device G1, the input device <NUM>, etc..

The machine guidance device <NUM> calculates the actual operating position of the attachment such as the bucket <NUM> based on the received signals and data. Then, the machine guidance device <NUM> compares the actual operating position of the attachment and a target surface, and calculates, for example, the distance between the bucket <NUM> and the target surface. The machine guidance device <NUM> also calculates the distance from the swing center axis of the shovel to the teeth ends of the bucket <NUM>, the inclination angle of the target surface, etc., and transmits these to the display device <NUM> as work information.

When the machine guidance device <NUM> and the controller <NUM> are provided separately, the machine guidance device <NUM> and the controller <NUM> are connected through CAN (Controller Area Network) to be able to communicate with each other.

The machine guidance device <NUM> includes a height calculating part <NUM>, a comparison part <NUM>, a display control part <NUM>, and a guidance data outputting part <NUM>.

The height calculating part <NUM> calculates the height of the end (teeth tips) of the bucket <NUM> from the angles of the boom <NUM>, the arm <NUM>, and the bucket <NUM> determined from the detection signals of the boom angle sensor S1, the arm angle sensor S2, and the bucket angle sensor S3.

The comparison part <NUM> compares the height of the end (teeth tips) of the bucket <NUM> calculated by the height calculating part <NUM> and the position of the target surface shown in the guidance data output by the guidance data outputting part <NUM>. Furthermore, the comparison part <NUM> determines the inclination angle of the target surface relative to the shovel. Various kinds of data determined in the height calculating part <NUM> and the comparison part <NUM> are stored in the storage device <NUM>.

The display control part <NUM> transmits the height of the bucket <NUM> and the inclination angle of the target surface, as determined by the comparison part <NUM>, to the display device <NUM> as work information. The display device <NUM> displays the work information transmitted from the display control part <NUM>, together with a captured image transmitted from the image capturing unit <NUM>, on the screen. A display screen layout of the display device <NUM> is described below. Furthermore, in such cases where the bucket <NUM> is positioned lower than the target surface, the display control part <NUM> can issue an alarm to the operator through the audio output device <NUM>.

<FIG> is a diagram illustrating the shovel performing the work of excavating a slope (an inclined surface) with the bucket <NUM> according to an embodiment. <FIG> is a diagram illustrating a forward looking view from the driver's seat in the cabin <NUM> of the shovel according to an embodiment.

As illustrated in <FIG>, the bucket <NUM> can be seen from the front window of the cabin <NUM>. In the cabin <NUM>, a driver's seat 10a is provided in the center, and the operation levers 26A and 26B are placed one on each side of the driver's seat 10a. The operator is seated on the driver's seat 10a and performs excavation work by moving the bucket <NUM> to a desired position by operating the operation lever 26A with the left hand and operating the operation lever 26B with the right hand.

The image display part <NUM> and the switch panel <NUM> of the display device <NUM> are placed on the front right of the driver's seat 10a (on the lower right of the front window). The operator of the shovel operates the operation levers 26A and 26B, etc., with both hands while looking at the bucket <NUM> outside the window, reading work information from the image display part <NUM> that comes into sight.

Here, the operator gazes at the bucket <NUM> outside the window during operations. Therefore, it is difficult for the operator to read the details of the information displayed on the image display part <NUM> that is in sight. Therefore, according to this embodiment, the contents displayed on the image display part <NUM> of the display device <NUM> are caused to differ between when the attachment is in operation and when the attachment is not in operation.

The controller <NUM> determines the presence or absence of an operation in the shovel based on the detection result of the pressure sensor 15a or 15b. For example, the controller <NUM> determines that the attachment is operating when any of the operation levers 26A through 26C is operated so that the pilot pressure detected by the pressure sensor 15a or 15b becomes or exceeds a predetermined value. Furthermore, the controller <NUM> determines that the attachment is non-operating when the pilot pressure detected by the pressure sensor 15a or 15b is less than a predetermined value.

Thus, the controller <NUM> determines the operating condition of the attachment from a pilot pressure detected by the sensor 15a or 15b, and determines that the condition in which an operation of the attachment is absent is "non-operating. " Furthermore, the controller <NUM> determines that the condition in which an operation of the attachment is present is "operating. " The controller <NUM> transmits an operation signal indicating whether the attachment is non-operating or operating to the display device <NUM>.

A criterion for determining the presence or absence of an operation by the controller <NUM> may be different from the above. The controller <NUM> may determine the operating condition of the attachment based on, for example, changes in the output signals of the boom angle sensor S1, the arm angle sensor S2, and the bucket angle sensor S3. Alternatively, for example, the controller <NUM> may determine that the condition in which either the arm <NUM> or the bucket <NUM> is operated is operating, and determine that the condition in which neither the arm <NUM> nor the bucket <NUM> is operated although the boom <NUM> is operated is non-operating. As yet another alternative, the controller <NUM> may determine the presence or absence of an operation in accordance with the condition of the gate lock lever.

The conversion part 40a of the display device <NUM> changes the contents displayed on the image display part <NUM> in accordance with the operation signal indicating the presence or absence of an operation transmitted from the controller <NUM>. Specifically, the work information transmitted from the machine guidance device <NUM> is displayed in detail while an actuator is non-operating, and a display of contents such as work information is simplified while an actuator is operating.

Thus, according to this embodiment, the contents displayed on the image display part <NUM> of the display device <NUM> are caused to differ between when an operation is present in the shovel and when an operation is absent in the shovel, and by simplifying the contents displayed on the image display part <NUM> during operations, the operator is enabled to read necessary information even while performing operations.

Next, display screen layouts of the display device <NUM> are described.

<FIG> is a diagram illustrating a non-operating-time screen 41V1 displayed on the image display part <NUM> of the display device <NUM> according to an embodiment.

As illustrated in <FIG>, the non-operating-time screen 41V1 includes a time display part <NUM>, a rotational speed mode display part <NUM>, a traveling mode display part <NUM>, an attachment display part <NUM>, an engine control status display part <NUM>, a remaining aqueous urea solution amount display part <NUM>, a remaining fuel amount display part <NUM>, a coolant water temperature display part <NUM>, an engine operating time display part <NUM>, a captured image display part <NUM>, and a work guidance display part <NUM>. The image displayed in each part is generated from various kinds of data transmitted from the controller <NUM> and captured images transmitted from the image capturing unit <NUM> by the conversion part 40a of the display device <NUM>.

The time display part <NUM> displays a current time. In the illustration of <FIG>, a digital display is employed, and a current time (<NUM>:<NUM>) is shown.

The rotational speed mode display part <NUM> displays a rotational speed mode set by the engine rotational speed adjustment dial <NUM> in an image. The rotational speed mode includes, for example, the above-described four modes, namely, SP mode, H mode, A mode, and idling mode. In the illustration of <FIG>, a symbol "SP" representing SP mode is displayed.

The traveling mode display part <NUM> displays a traveling mode. The traveling mode represents the setting of traveling hydraulic motors using a variable displacement pump. For example, the traveling mode includes a low-speed mode and a high-speed mode. A "turtle"-shaped mark is displayed in the low-speed mode, and a "rabbit"-shaped mark is displayed in the high-speed mode. In the illustration of <FIG>, the "turtle"-shaped mark is displayed to make it possible for the operator to recognize that the low-speed mode is set.

The attachment display part <NUM> displays an image representing an attachment that is attached. Various attachments such as the bucket <NUM>, a rock drill, a grapple, and a lifting magnet are attached to the shovel. The attachment display part <NUM> displays, for example, marks shaped like these attachments and numbers corresponding to the attachments. According to this embodiment, the bucket <NUM> is attached as an end attachment, and as illustrated in <FIG>, the attachment display part <NUM> is blank. When a rock drill is attached as an end attachment, for example, a rock drill-shaped mark is displayed together with a number representing the magnitude of the output of the rock drill.

The engine control status display part <NUM> displays the control status of the engine <NUM>. In the illustration of <FIG>, "automatic deceleration and automatic stop mode" is selected as the control status of the engine <NUM>. The "automatic deceleration and automatic stop mode" means a control status to automatically reduce the engine rotational speed and further to automatically stop the engine <NUM> in accordance with the duration of a condition in which the engine load is low. Other control statuses of the engine <NUM> include "automatic deceleration mode," "automatic stop mode," "manual deceleration mode," etc..

The remaining aqueous urea solution amount display part <NUM> displays the status of the remaining amount of an aqueous urea solution stored in an aqueous urea solution tank in an image. In the illustration of <FIG>, a bar graph representing a current status of the remaining amount of an aqueous urea solution is displayed. The remaining amount of an aqueous urea solution is displayed based on the output data of a remaining aqueous urea solution amount sensor provided in the aqueous urea solution tank.

The remaining fuel amount display part <NUM> displays the status of the remaining amount of fuel stored in a fuel tank. In the illustration of <FIG>, a bar graph representing a current status of the remaining amount of fuel is displayed. The remaining amount of fuel is displayed based on the output data of a remaining fuel amount sensor provided in the fuel tank.

The coolant water temperature display part <NUM> displays the temperature condition of engine coolant water. In the illustration of <FIG>, a bar graph representing the temperature condition of engine coolant water is displayed. The temperature of engine coolant water is displayed based on the output data of the water temperature sensor 11c provided on the engine <NUM>.

The engine operating time display part <NUM> displays the cumulative operating time of the engine <NUM>. In the illustration of <FIG>, a cumulative operating time since the restart of counting by the driver is displayed together with a unit "hr (hour). " A lifelong operating time in the entire period after the manufacture of the shovel or a section operating time since the restart of counting by the operator is displayed in the engine operating time display part <NUM>.

The captured image display part <NUM> displays an image captured by the image capturing unit <NUM>. In the illustration of <FIG>, an image captured by the back-side camera 80B is displayed in the captured image display part <NUM>. A captured image captured by the left-side camera <NUM> or the right-side camera 80R may also be displayed in the captured image display part <NUM>. Furthermore, images captured by two or more of the back-side camera 80B, the left-side camera <NUM>, and the right-side camera 80R may also be displayed side by side in the captured image display part <NUM>. Moreover, a bird's-eye view image into which captured images captured by the back-side camera 80B, the left-side camera <NUM>, and the right-side camera 80R, respectively, are combined may also be displayed in the captured image display part <NUM>.

Each camera is so installed as to include part of the cover 3a of the upper rotating structure <NUM> in a captured image. The operator has a better sense of distance between an object displayed in the captured image display part <NUM> and the shovel because of inclusion of part of the cover 3a in a displayed image.

In the captured image display part <NUM>, an image capturing unit icon <NUM> representing the orientation of the image capturing unit <NUM> that has captured a captured image that is being displayed is displayed. The image capturing unit icon <NUM> is composed of a shovel icon 421a representing the shape of the shovel in a plan view and a strip-shaped orientation indicator icon 421b representing the orientation of the image capturing unit <NUM> that has captured a captured image that is being displayed.

In the illustration of <FIG>, the orientation indicator icon 421b is displayed below the shovel icon 421a (on the opposite side from the attachment) to indicate that a rearview image of the shovel captured with the back-side camera 80B is displayed in the captured image display part <NUM>. For example, when an image captured with the right-side camera 80R is displayed in the captured image display part <NUM>, the orientation indicator icon 421b is displayed to the right of the shovel icon 421a. When an image captured with the left-side camera <NUM> is displayed in the captured image display part <NUM>, the orientation indicator icon 421b is displayed to the left of the shovel icon 421a.

For example, the operator can switch an image to display in the captured image display part <NUM> to an image captured by another camera or the like by depressing an image change switch provided in the cabin <NUM>.

If the shovel is not provided with the image capturing unit <NUM>, different information may be displayed in place of the captured image display part <NUM>.

The work guidance display part <NUM> includes a position indicator image <NUM>, a first target surface display image <NUM>, a second target surface display image <NUM>, and a numerical value information image <NUM>, and displays various kinds of work information.

The position indicator image <NUM> is a bar graph of vertically arranged bars 431a, and shows a distance from the working part of the attachment (for example, the end of the bucket <NUM>) to a target surface. According to this embodiment, in accordance with the distance from the end of the bucket <NUM> to the target surface, one of the seven bars serves as a bucket position indicator bar 431b (the third bar from the top in <FIG>) that is displayed in a color different from that of the other bars. Here, a point at the end of the working part in the left-to-right direction is preset as the position of the working part to be indicated in the position indicator image <NUM>. The position of the working part to be indicated is, for example, the center, the left end, or the right end of the end of the working part. Furthermore, the position of the working part to be indicated may be changed as desired in the contents of work or at a work site. Furthermore, a relative distance between the back surface part of the working part and the target surface may be shown. The position indicator image <NUM> may include multiple images to be able to show the distance from the end of the bucket <NUM> to the target surface with more accuracy. For example, multiple bar graphs may be displayed to each show a relative distance between one of different points at the end of the working part in the left-to-right direction and the target surface. In this case, for example, a bar graph showing a relative distance between the left end of the end of the working part and the target surface and a bar graph showing a relative distance between the right end of the end of the working part and the target surface are displayed. The operator can understand the positional relationship between the working part and the target surface in more detail. Here, a central bar (a bar in the middle) among the bars 431a corresponds to the target surface. Therefore, a central bar (a bar in the middle) in a vertical direction (upward or downward direction in which the bars 431a are aligned in the position indicator image <NUM>) alone may be different in color from the other bars. Thus, the target surface is set in a vertically central region of the bars 431a.

In a bar graph displayed in the position indicator image <NUM>, for example, when the end of the bucket <NUM> is above the target surface, an upper bar is displayed in a color different from that of the other bars 431a as the bucket position indicator bar 431b in accordance with a distance from the target surface. Furthermore, when the end of the bucket <NUM> is below the target surface, a lower bar is likewise displayed in a color different from that of the other bars 431a as the bucket position indicator bar 431b in accordance with a distance from the target surface. Thus, the bucket position indicator bar 431b is displayed to move upward or downward in accordance with the position of the end of the bucket <NUM> relative to the target surface and the distance from the end of the bucket <NUM> to the target surface. The operator can determine the position of the end of the bucket <NUM> relative to the target surface and the distance from the end of the bucket <NUM> to the target surface by viewing the position indicator image <NUM>.

The first target surface display image <NUM> schematically shows the relationship between the bucket <NUM> and the target surface. In the first target surface display image <NUM>, the bucket <NUM> and the target surface in a forward looking view from the shovel that the operator has when seated in the cabin <NUM> are schematically displayed with a bucket icon <NUM> and a target surface <NUM>. The bucket icon <NUM> is shown in the shape of the bucket <NUM> viewed from the cabin <NUM>. The target surface <NUM> is displayed with the tilt angle of the bucket <NUM> relative to the actual target surface (<NUM>° in the illustration of <FIG>). The interval between the bucket icon <NUM> and the target surface <NUM> is displayed to vary in accordance with the actual distance from the end of the bucket <NUM> to the target surface. Likewise, the tilt angle of the bucket <NUM> is displayed to vary in accordance with the positional relationship between the actual bucket <NUM> and target surface.

The operator can understand the positional relationship between the bucket <NUM> and the target surface and the inclination angle of the target surface by viewing the first target surface display image <NUM>. In the first target surface display image <NUM>, the target surface <NUM> may be displayed with an inclination angle that is greater than actually is to improve visibility for the operator. The operator can recognize an approximate inclination angle from the target surface <NUM> displayed in the first target surface display image <NUM>. Furthermore, when the operator desires to know a precise inclination angle, the operator can know an actual inclination angle by viewing an inclination angle numerically displayed below the target surface <NUM>.

The second target surface display image <NUM> schematically shows the relationship between the bucket <NUM> and the target surface viewed from the side. In the second target surface display image <NUM>, the bucket icon <NUM> and the target surface <NUM> are displayed. The bucket icon <NUM> is shown in the shape of the bucket <NUM> viewed from the side. The target surface <NUM> is displayed with an inclination angle relative to a horizontal plane (<NUM>° in the illustration of <FIG>). The interval between the bucket icon <NUM> and the target surface <NUM> is displayed to vary in accordance with the actual distance from the end of the bucket <NUM> to the target surface. The inclination angle is displayed to vary in accordance with the positional relationship between the actual bucket <NUM> and target surface.

The operator can understand the positional relationship between the bucket <NUM> and the target surface and the inclination angle of the target surface by viewing the second target surface display image <NUM>. In the second target surface display image <NUM>, the target surface <NUM> may be displayed with an inclination angle that is greater than actually is to improve visibility for the operator. The operator can recognize an approximate inclination angle from the target surface <NUM> displayed in the second target surface display image <NUM>. Furthermore, when the operator desires to know a precise inclination angle, the operator can know an actual inclination angle by viewing an inclination angle numerically displayed below the target surface <NUM>.

The numerical value information image <NUM> displays various kinds of numerical values indicating the positional relationship between the end of the bucket <NUM> and the target surface, etc. In the numerical value information image <NUM>, the swing angle of the upper rotating structure <NUM> relative to a reference (<NUM>° in the illustration of <FIG>) is displayed together with an icon showing a shovel. Furthermore, in the numerical value information image <NUM>, the height of the end of the bucket <NUM> from the target surface (the vertical distance between the end of the bucket <NUM> and the target surface, which is <NUM> in the illustration of <FIG>) is displayed together with an icon showing the positional relationship with the target surface. In <FIG>, the positional relationship between a preset part of the bucket, which is a working part, and the target surface is shown in a numerical value. When it is desired to show the positional relationship between each of the left and right ends of the blade edge or the back surface of the working part and the target surface in a numerical value, multiple combinations of an icon and numerical value information may be displayed side by side.

When an operation is absent in the shovel, the above-described non-operating-time screen 41V1 is displayed on the image display part <NUM> of the display device <NUM>. The operator can specifically check, as numerical value information, the relative positional relationship between the bucket <NUM> and the target surface, etc., from various kinds of numerical values displayed in the numerical value information image <NUM>. Numerical value information different from that described above may be displayed in the numerical value information image <NUM>.

<FIG> is a diagram illustrating an operating-time screen 41V2 displayed on the image display part <NUM> of the display device <NUM> according to an embodiment.

When the attachment is operated by the operator, the controller <NUM> transmits a signal indicating the presence of an operation to the display device <NUM>, and the operating-time screen 41V2 illustrated in <FIG> is displayed on the image display part <NUM> of the display device <NUM>.

As illustrated in <FIG>, like the non-operating-time screen 41V1, the operating-time screen 41V2 includes the time display part <NUM>, the rotational speed mode display part <NUM>, the traveling mode display part <NUM>, the attachment display part <NUM>, the engine control status display part <NUM>, the remaining aqueous urea solution amount display part <NUM>, the remaining fuel amount display part <NUM>, the coolant water temperature display part <NUM>, the engine operating time display part <NUM>, the captured image display part <NUM>, and the work guidance display part <NUM>.

The non-operating-time screen 41V1 and the operating-time screen 41V2 are different in the configuration of the work guidance display part <NUM>. The work guidance display part <NUM> of the operating-time screen 41V2 includes the position indicator image <NUM>, the first target surface display image <NUM>, the second target surface display image <NUM>, and a target surface indicator image <NUM>. In the operating-time screen 41V2, the position indicator image <NUM> is displayed larger and the first target surface display image <NUM> and the second target surface display image <NUM> are displayed smaller than in the non-operating-time screen 41V1. Furthermore, in the operating-time screen 41V2, the numerical value information image <NUM>, which is displayed in the non-operating-time screen 41V1, is not displayed, and the target surface indicator image <NUM> is displayed.

According to the position indicator image <NUM> in the operating-time screen 41V2, the bars 431a in the non-operating-time screen 41V1 are enlarged and displayed. Furthermore, the target surface indicator image <NUM> is displayed next to and alongside the position indicator image <NUM>. Thus, as a method of changing the contents displayed in the work guidance display part <NUM>, the form of display of the position indicator image <NUM> changes, for example.

The target surface indicator image <NUM> is composed of, for example, two regions 435a and 435b that are displayed in different colors, and the boundary between the region 435a and the region 435b represents the position of the target surface <NUM>. The target surface indicator image <NUM> may alternatively be composed of three or more regions that are displayed in different colors, and may have any boundary represent the position of the target surface <NUM>.

According to this embodiment, in the target surface indicator image <NUM>, the boundary between the region 435a and the region 435b representing the target surface <NUM> is formed at a position corresponding to the fourth bar 431a from the top in the position indicator image <NUM>.

According to this configuration, when the end of the bucket <NUM> is above the target surface, in the position indicator image <NUM>, one of the upper three bars is displayed in a color different from that of the other bars 431a as the bucket position indicator bar 431b in accordance with the distance between the end of the bucket <NUM> and the target surface. Furthermore, when the end of the bucket <NUM> is near the target surface, in the position indicator image <NUM>, the fourth bar from the top (from the bottom) is displayed in a color different from that of the other bars 431a as the bucket position indicator bar 431b. Furthermore, when the end of the bucket <NUM> is below the target surface, in the position indicator image <NUM>, one of the lower three bars is displayed in a color different from that of the other bars 431a as the bucket position indicator bar 431b in accordance with the distance between the end of the bucket <NUM> and the target surface.

Thus, in the operating-time screen 41V2, the position indicator image <NUM> becomes larger than in the non-operating-time screen V1 and is displayed together with the target surface indicator image <NUM>. Therefore, the operator can easily understand the positional relationship between the end of the bucket <NUM> and the target surface while operating the bucket <NUM>, without gazing at the operating-time screen 41V2 during operations. Accordingly, the operator can accurately perform work while checking the positional relationship between the end of the bucket <NUM> and the target surface.

As illustrated in <FIG>, the position indicator image <NUM> may be displayed over the target surface indicator image <NUM>. A superimposed display of the position indicator image <NUM> and the target surface indicator image <NUM> makes it possible to more easily understand the positional relationship between the end of the bucket <NUM> and the target surface. Alternatively, as illustrated in <FIG>, in the position indicator image <NUM>, a bar indicating the vicinity of the target surface may be displayed in a color different from those of the bucket position indicator bar 431b and the other bars 431a as a target surface indicator bar 431c. Such display makes it possible to easily understand the positional relationship between the end of the bucket <NUM> and the target surface.

In addition, for example, a display change switch may be provided in the cabin <NUM> to allow the operator to easily switch the display of the position indicator image <NUM> and the target surface indicator image <NUM> from <FIG> to the layout illustrated in <FIG>. By properly switching to a display layout that is easy for the operator to see, it is possible to perform work with more accuracy. The color of the target surface indicator bar 431c may be the same as the color of the other bars 431a. In this case as well, the target surface is set in a vertically central region of the bars 431a.

In the work guidance display part <NUM> of the operating-time screen 41V2, the first target surface display image <NUM> and the second target surface display image <NUM> are displayed smaller than in the non-operating-time screen 41V1. In the first target surface display image <NUM> and the second target surface display image <NUM>, a display of numerical values such as the inclination angle of the target surface and the distance from the swing center axis to the end of the bucket <NUM>, which are displayed in the non-operating-time screen 41V1, is omitted.

For example, even if the above-described numerical values are displayed in the first target surface display image <NUM> and the second target surface display image <NUM>, it is difficult for the operator, who cannot gaze at the operating-time screen 41V2 while operating the attachment, to check these numerical values. Therefore, a display of the above-described numerical values is omitted, and the first target surface display image <NUM> and the second target surface display image <NUM> are configured to show the relationship between the bucket icon <NUM> and the target surface <NUM> in a simplified manner.

The omission of numerical values improves the visibility of the first target surface display image <NUM> and the second target surface display image <NUM>, thus making is possible for the operator to accurately perform work while checking the positional relationship between the bucket <NUM> and the target surface during operations.

Furthermore, in the first target surface display image <NUM> and the second target surface display image <NUM>, the bucket icon <NUM> is displayed in a shape that is an exaggeration of the actual shape of the bucket <NUM>. Furthermore, the target surface <NUM> is displayed with an inclination angle that is greater than actually is. As a result of thus displaying the relationship between the actual bucket <NUM> and target surface in an exaggerated manner, it becomes easier for the operator to check the relationship between the bucket <NUM> and the target surface during operations.

As described above, according to the shovel of this embodiment, the contents displayed on the image display part <NUM> of the display device <NUM> differ between when the attachment is operating and when the attachment is non-operating. At the operating time, the position indicator image <NUM> is larger than at the non-operating time and is displayed together with the target surface indicator image <NUM>. Furthermore, various kinds of numerical values displayed at the non-operating time are not displayed at the operating time. Accordingly, the operator can easily understand the positional relationship between the bucket <NUM> and the target surface without gazing at the image display part <NUM> of the display device <NUM>, and can accurately perform work while checking the positional relationship between the bucket <NUM> and the target surface.

In addition to those described above, the non-operating-time screen 41V1 and the operating-time screen 41V2 may include a fuel efficiency display part to display fuel efficiency and a hydraulic oil temperature display part to display the temperature condition of hydraulic oil in a hydraulic oil tank. The remaining aqueous urea solution amount display part <NUM>, the remaining fuel amount display part <NUM>, and the coolant water temperature display part <NUM>, which are displayed in a bar graph in the illustrations of <FIG> and <FIG>, may alternatively be of needle display, and the form of display of the regions is not limited to what illustrated in this embodiment. Furthermore, the arrangement of the regions is not limited to the configuration illustrated in this embodiment.

A shovel according to embodiments is described above. The present invention, however, is not limited to the above-described embodiments, and variations and modifications may be made without departing from the scope of the present invention, which is defined in the appended claims.

Claim 1:
A shovel comprising:
a traveling undercarriage (<NUM>) configured to travel;
an upper rotating structure (<NUM>) swingably mounted on the traveling undercarriage (<NUM>);
a cab (<NUM>) mounted on the upper rotating structure (<NUM>);
an attachment including a working part (<NUM>) configured to perform work; and
a display device (<NUM>) provided in the cab (<NUM>),
wherein the display device (<NUM>) is configured to display an image including a work guidance display part (<NUM>), the work guidance display part (<NUM>) showing an attitude of the working part (<NUM>) and a target surface, and
characterised in that
the display device (<NUM>) is configured to display a position indicator image (<NUM>) in the work guidance display part (<NUM>) such that the position indicator image (<NUM>) is larger when the attachment is in operation than when the attachment is not in operation, the position indicator image (<NUM>) showing a positional relationship between the working part (<NUM>) and the target surface.