Mixer truck and state detection device

Abstract

To provide a mixer vehicle capable of detecting content state in a mixer drum which reduces working man-hour.SOLUTION: A state detection device includes: a housing 21; a camera 30 attached to a hopper cover 6 via the housing 21 so as to be stored inside a hopper 5 when the hopper 5 is closed, and detects a content state; and a shutter part 40 rotatably attached to the housing 21 via a shutter shaft 40A, the shutter part 40 opens the camera 30 without covering it when the hopper 5 is closed by a hopper cover 6, and is configured to rotate around the shutter shaft 40A to cover the camera 30 when the hopper cover 6 rotates so that the hopper 5 changes from a closed state to an open state.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a mixer vehicle and a state detection device. [Background technology]

[0002] Patent Document 1 discloses a device for estimating the amount of fresh concrete in a mixer drum. This device has a camera that can capture images of the inside of the mixer drum, and the camera is attached to the hopper cover so that it is housed inside the hopper when the hopper cover closes the hopper opening. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-025680 Summary of the Invention [Problem to be solved by the invention]

[0004] In the device described in Patent Document 1, when contents such as ready-mixed concrete are poured into the mixer drum, the camera needs to be temporarily removed from the hopper cover to prevent the contents from adhering to the camera. Thus, with the device described in Patent Document 1, the camera needs to be attached and detached every time contents are poured.

[0005] The present invention has been made in view of the above-mentioned problems, and has as its object to reduce the number of work steps in a mixer vehicle and a state detection device capable of detecting the state of the contents of a mixer drum. [Means for solving the problem]

[0006] The present invention is a mixer vehicle comprising a mixer drum rotatably mounted on the vehicle, and a state detection device for detecting the state of the contents of the mixer drum, wherein the mixer drum has a hopper for pouring the contents into it, and a hopper cover rotatably attached to the hopper via a cover rotation shaft for opening and closing the hopper, and the state detection device has a housing, a sensor unit that detects the state of the contents and is attached to the hopper cover via the housing so as to be contained inside the hopper when the hopper is closed, and a shutter unit rotatably attached to the housing via a shutter rotation shaft, wherein the shutter unit is configured to open the sensor unit without covering it when the hopper is closed by the hopper cover, and to rotate about the shutter rotation shaft to cover the sensor unit as the hopper cover rotates so that the hopper changes from a closed state to an open state.

[0007] Furthermore, the present invention is characterized in that the sensor unit is arranged so that the sensor axis extends downward of the vehicle toward the bottom of the mixer drum, and the shutter rotation axis is arranged in the housing so that it is located lower than the sensor unit when the hopper is closed by the hopper cover.

[0008] The present invention also provides a condition detection device for detecting the condition of the contents in a mixer drum, comprising: a housing; a sensor unit that detects the condition of the contents and is attached to a hopper cover via the housing so as to be housed inside the hopper when the hopper is closed; and a shutter unit that is rotatably attached to the housing via a shutter rotation shaft, wherein the shutter unit opens without covering the sensor unit when the hopper is closed by the hopper cover, and rotates around the shutter rotation shaft to cover the sensor unit as the hopper cover rotates so that the hopper changes from a closed state to an open state.

[0009] In these inventions, as the hopper cover rotates about the cover rotation axis from a closed state to an open state, the shutter rotates about the shutter rotation axis due to gravity to cover the sensor. When the hopper is in the open state, the shutter covers the sensor, preventing the contents from adhering to the sensor. This eliminates the need to remove the sensor from the hopper cover every time the contents are added to the mixer drum.

[0010] The present invention is also characterized in that the state detection device further comprises a stopper portion that restricts the shutter portion from rotating beyond a predetermined amount in the direction that opens the sensor portion.

[0011] In this invention, when the hopper cover is used to open the hopper, the shutter section can be prevented from rotating in a direction that opens the sensor section due to the inertia of the rotation of the hopper cover, thereby more reliably covering the sensor section when the hopper is opened.

[0012] Furthermore, the present invention is characterized in that the shutter section is detachably attached to the housing.

[0013] In this invention, even if the contents adhere to the shutter part, the shutter part can be easily replaced.

[0014] The present invention is also characterized in that the state detection device further includes a control unit that processes the detection results of the sensor unit, and the control unit pre-stores at least one of the detection results of the sensor unit when the hopper is closed and the shutter unit covers the sensor unit, and the detection result of the sensor unit when the hopper is open and the shutter unit opens the sensor unit, as a reference detection value, and detects the open / closed state of the shutter unit by comparing the reference detection value with the detection value detected by the sensor unit.

[0015] In this invention, it is possible to confirm whether the sensor section is opened or closed by the shutter section. [Effects of the Invention]

[0016] According to the present invention, the number of work steps required for a mixer vehicle and a state detection device capable of detecting the state of the contents of a mixer drum can be reduced. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a side view of a mixer vehicle according to an embodiment of the present invention. [Figure 2] 1 is a block diagram showing a configuration of a state detection device according to an embodiment of the present invention; [Figure 3] FIG. 2 is an enlarged view showing the measuring unit in the embodiment of the present invention, showing a state in which the hopper is closed. [Figure 4] FIG. 10 is an enlarged view showing the measuring unit according to the embodiment of the present invention, illustrating a state in which the hopper is in the middle of being opened. [Figure 5] FIG. 2 is an enlarged view showing the measuring unit according to the embodiment of the present invention, showing a state in which the hopper is open. [Figure 6] FIG. 10 is an enlarged view showing the measurement unit according to the embodiment of the present invention, illustrating a state in which the hopper cover is in contact with a stopper portion. DETAILED DESCRIPTION OF THE INVENTION

[0018] A mixer vehicle 101 and a state detection device 100 according to an embodiment of the present invention will be described below with reference to the drawings.

[0019] First, the overall configuration of a mixer vehicle 101 equipped with a state detection device 100 will be described with reference to Figure 1. In the following, an example will be described in which the mixer vehicle 101 is on a horizontal plane, and the front and rear of the direction of travel of the mixer vehicle 101 will be referred to as the "front-rear direction," the vertical direction as the "up-down direction," and the direction perpendicular to the front-rear direction and the up-down direction (the width direction of the vehicle) as the "left-right direction." The left side when looking forward in the direction of travel of the vehicle corresponds to the left side in the left-right direction.

[0020] The mixer truck 101 transports contents such as so-called ready-mixed concrete (hereinafter referred to as "ready-mixed concrete"), such as mortar or ready-mixed concrete, in a mixer drum 2 mounted on a base 1.

[0021] As shown in Fig. 1, the mixer drum 2 is a container rotatably mounted on the base 1. The mixer drum 2 is mounted so that its rotation axis O1 extends in the front-to-rear direction of the mixer vehicle 101. The mixer drum 2 is also mounted at an incline in the front-to-rear direction so that it gradually becomes higher toward the rear of the base 1.

[0022] A pair of blades 3 and 4 are provided inside the mixer drum 2, protruding from the inner wall and extending spirally along the rotation axis O1.

[0023] The mixer drum 2 has an opening 2A formed at its rear end, and fresh concrete is charged and discharged through the opening 2A.

[0024] A hopper 5 for charging ready-mixed concrete is provided above the opening 2A of the mixer drum 2. The hopper 5 guides ready-mixed concrete charged from outside into the mixer drum 2 through the opening 2A.

[0025] A hopper cover 6 that covers the opening of the hopper 5 is provided above the hopper 5 and is rotatable via a shaft 6A that serves as a cover rotation axis. The shaft 6A is provided on the hopper 5 so as to extend in the left-right direction. The hopper 5 is opened and closed by the hopper cover 6 rotating about the shaft 6A. In other words, the hopper cover 6 rotates in the up-down direction around the shaft 6A that extends in the left-right direction. Hereinafter, with regard to the rotation direction of the hopper cover 6 about the shaft 6A, the direction in which the hopper 5 is opened will also be referred to as the "opening direction" (the direction of arrow A in FIG. 3), and the direction in which the hopper 5 is closed will also be referred to as the "closing direction" (the direction of arrow B in FIG. 3).

[0026] The mixer drum 2 is driven by a traveling engine (not shown) mounted on the mixer vehicle 101 as a power source, and is rotated forward and reverse and accelerated and decelerated by the drum drive device 7. When the mixer drum 2 is rotated forward by the drum drive device 7, the ready-mixed concrete in the mixer drum 2 is agitated by the blades 3 and 4, and when the mixer drum 2 is rotated in reverse, the ready-mixed concrete in the mixer drum 2 is sent by the blades 3 and 4 to the opening 2A side and discharged to the outside.

[0027] Next, the state detection device 100 that detects the state of the ready-mixed concrete in the mixer drum 2 will be described.

[0028] The state detection device 100 is a device for detecting states such as the temperature, slump value, loaded amount, and air volume of the ready-mixed concrete in the mixer drum 2. The following describes an example in which the state detection device 100 detects the loaded amount of ready-mixed concrete (amount of ready-mixed concrete) from an image captured inside the mixer drum 2.

[0029] As shown in Figures 2 and 3, the state detection device 100 includes a measurement unit 20 for measuring state quantities indicating the state of the ready-mixed concrete in the mixer drum 2, and a control unit 50 for detecting the state of the ready-mixed concrete from the detection results of the measurement unit 20.

[0030] 3, the measurement unit 20 is attached to the back surface of the hopper cover 6 (the surface facing the inside of the hopper 5) at a position spaced apart from the shaft 6A in the radial direction of the shaft 6A. The measurement unit 20 has a housing 21, a camera 30 as a sensor unit housed in the housing 21, and a shutter unit 40 rotatably attached to the housing 21 via a shutter shaft 40A as a shutter rotation axis.

[0031] The housing 21 is a substantially rectangular box-shaped member, and is attached to the back surface of the hopper cover 6 via a spacer 23 for adjusting the angle of the axis (optical axis O2) of the camera 30, which serves as the sensor axis. The housing 21 has an accommodation recess 22 formed therein, which has an opening 22A that exposes the lens 31 of the camera 30 and accommodates the camera 30. The opening 22A opens in a wall of the housing 21 opposite the lens 31 of the camera 30, and faces the interior of the mixer drum 2 with its central axis pointing toward the bottom of the mixer drum 2. Light is incident on the lens 31 of the camera 30 housed in the housing 21 through the opening 22A.

[0032] The camera 30 functions as an imaging unit capable of capturing images of the inside of the mixer drum 2. Images (still images or videos) of the inside of the mixer drum 2 captured by the camera 30 are input to the control unit 50 as information indicating the state of the ready-mixed concrete in the mixer drum 2. As shown in FIG. 3 , the camera 30 is attached to the back side of the hopper cover 6 via a housing 21 and a spacer 23 so that the camera 30 is housed inside the hopper 5 when the hopper cover 6 is in the closed state of the hopper 5. The housing 21 may be configured integrally with the case of the camera 30 itself. In other words, the case of the camera 30 itself may function as the housing 21.

[0033] The camera 30 is provided so that, when the hopper cover 6 closes the hopper 5, it can capture an image of the interior of the mixer drum 2 through the opening 2A of the mixer drum 2. Specifically, the camera 30 is provided on the hopper cover 6 at an angle that tilts downward toward the front of the mixer vehicle 101 so that the optical axis O2 extends toward the bottom of the mixer drum 2 when the hopper 5 is closed. That is, when the hopper 5 is closed, the optical axis O2 of the camera 30 is not parallel to the horizontal, but has an inclination angle θ2 with respect to the horizontal that is greater than 0° and less than 90°. As shown in FIG. 3 , the inclination angle θ2 of the optical axis O2 of the camera 30 (the smaller angle with respect to the horizontal) is preferably the same as the inclination angle θ1 of the rotation axis O1 of the mixer drum 2 (see FIG. 1 ), which is also inclined with respect to the horizontal (the optical axis O2 of the camera 30 and the rotation axis O1 of the mixer drum 2 are parallel), or is smaller than the inclination angle θ1 of the rotation axis O1 of the mixer drum 2. Furthermore, when the inclination angle θ2 of the optical axis O2 of the camera 30 is smaller than the inclination angle θ1 of the rotation axis O1 of the mixer drum 2, it is desirable that the inclination angle θ2 of the optical axis O2 of the camera 30 be equal to or smaller than the inclination angle θ1 (within a range of 15° to 20°) of the rotation axis O1 of the mixer drum 2 and be equal to or larger than 10°. With this configuration, the ready-mixed concrete at the bottom of the mixer drum 2 or the upper portion of the bottom of the mixer drum 2 can be photographed more reliably by the camera 30.

[0034] Although not shown, a light source that emits light is provided for the camera 30. The light source is provided on the rear side of the hopper cover 6 together with the camera 30, and emits light into the mixer drum 2 so that the interior of the mixer drum 2 can be viewed by the camera 30. The light source may be, for example, an LED light, and may be integrated with the camera 30.

[0035] The shutter unit 40 is a plate-shaped member that has light-blocking properties and can cover the lens 31 of the camera 30 (in other words, the opening 22A of the housing 21). One end of the plate-shaped shutter unit 40 is attached to the housing 21 via a shutter shaft 40A. The shutter unit 40 rotates around the shutter shaft 40A to move between a state in which it covers the lens 31 of the camera 30 and blocks light from entering the lens 31 of the camera 30 (hereinafter referred to as the "blocking state") and a state in which it opens (exposes) the lens 31 of the camera 30 and allows light to enter the lens 31 of the camera 30 (hereinafter also referred to as the "open state"). Hereinafter, with regard to the rotation direction of the shutter unit 40 around the shutter shaft 40A, the rotation direction from the open state to the blocking state will be referred to as the "blocking direction" (the direction of arrow C in FIG. 3), and the rotation direction from the blocking state to the open state will be referred to as the "opening direction" (the direction of arrow D in FIG. 3).

[0036] The shutter shaft 40A is disposed so as to be positioned vertically lower than the camera 30 (specifically, the lens 31) when the hopper 5 is closed by the hopper cover 6. The shutter shaft 40A is disposed in the housing 21 so as to extend in the left-right direction (the direction perpendicular to the paper surface in FIG. 3), in other words, parallel to the shaft 6A. The shutter shaft 40A is configured to be detachable from the housing 21, and therefore the shutter unit 40 is also configured to be detachable from the housing 21. Because the shutter unit 40 is detachable from the housing 21 in this way, the shutter unit 40 can be easily replaced.

[0037] The housing 21 is also provided with a stopper portion 24 that restricts rotation of the shutter portion 40 in the opening direction (counterclockwise in FIG. 3 ) beyond a predetermined amount. The stopper portion 24 is formed so as to protrude perpendicularly from a flat wall portion of the housing 21, in which the opening 22A is provided, toward the side opposite the camera 30. In other words, the stopper portion 24 is formed so as to protrude further from the housing 21 toward the tip end (forward side) of the optical axis O2 of the camera 30. More preferably, as shown in FIG. 6 (described later), the stopper portion 24 is formed so as to protrude rearward (to the right in FIG. 6 ) of the vehicle beyond the center of the shutter shaft 40A when the hopper 5 is fully open. For example, the stopper portion 24 is molded integrally with the housing 21 using resin. Note that the materials and configurations of the housing 21 and the stopper portion 24 are not limited thereto. For example, the stopper portion 24 may be formed separately from the housing 21 using the same or a different material and attached to the housing 21.

[0038] The control unit 50 is composed of a microcomputer equipped with a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), and I / O interface (Input / Output Interface). The RAM stores data for CPU processing, the ROM stores the CPU control program and the like in advance, and the I / O interface is used for inputting and outputting information to and from connected devices.

[0039] The control unit 50 is a controller provided in the cab of the mixer vehicle 101, for example, as shown in Figure 1, and acquires the detection results of the camera 30 of the measurement unit 20 by wired or wireless means. The amount of ready-mixed concrete estimated by the control unit 50 is displayed on a monitor or the like (not shown).

[0040] As shown in Fig. 2, the control unit 50 has a processing unit 51 that estimates the state of the ready-mixed concrete amount from the detection results of the camera 30, and a storage unit 52 that stores various information. Note that each component shown in Fig. 2 shows each function of the control unit 50 as a virtual unit, and does not necessarily mean that it exists physically.

[0041] The processing unit 51 processes the image captured by the camera 30 to extract the area where the ready-mixed concrete exists, and estimates the amount of ready-mixed concrete in the mixer drum 2 from the extracted estimated area. The amount of ready-mixed concrete can be estimated from the area of ​​the estimated area obtained by calculation, information such as a map showing the relationship between the area of ​​the estimated area and the amount of ready-mixed concrete stored in the memory unit 52, and the installation position and attitude of the camera 30 (tilt angle θ2 of the optical axis O2) that are known in advance. Note that the estimation of the amount of ready-mixed concrete based on the captured image is not limited to these methods.

[0042] The control unit 50 is also configured to be able to execute an open / closed state detection process that determines whether the camera 30 is in a closed state or an open state based on the detection result of the camera 30. The open / closed state detection process will be described later.

[0043] The storage unit 52 stores various types of information required to estimate the amount of ready-mixed concrete and various types of information required to execute the open / close detection process.

[0044] Next, the operation and function of this embodiment will be described.

[0045] 3, when the hopper 5 is closed by the hopper cover 6, the hopper cover 6 extends in a substantially horizontal direction, and the camera 30 is housed in the hopper 5. In this state, the shutter shaft 40A is positioned lower than the camera 30, and the camera 30 is inclined horizontally so that the optical axis O2 of the camera 30 points downward as it approaches the front of the mixer vehicle 101 toward the bottom of the mixer drum 2. Therefore, the shutter assumes a position in which it extends vertically downward from the shutter shaft 40A due to gravity (its own weight), and opens the lens 31 of the camera 30 (open state).

[0046] When ready-mixed concrete is poured into the hopper 5, the hopper 5 is opened by the hopper cover 6. As shown in FIG. 4, in the process in which the hopper cover 6 rotates around the shaft 6A to open the hopper 5 from a state in which the hopper 5 is closed by the hopper cover 6, the shutter unit 40 rotates around the shutter shaft 40A due to its own weight as the hopper cover 6 rotates. In other words, the shutter unit 40 rotates in the shielding direction relative to the camera 30 as the hopper cover 6 rotates in the opening direction. Note that in FIG. 4, the closed state of the hopper 5 is shown by a dashed line.

[0047] When the hopper cover 6 is further rotated in the opening direction from the state shown in Fig. 4, the shutter unit 40 comes into contact with the housing 21 so as to cover the lens 31 of the camera 30, and the rotation of the shutter unit 40 associated with the rotation of the hopper cover 6 in the opening direction is stopped. As shown in Fig. 5, when the hopper cover 6 is rotated approximately 180° from the closed state of the hopper 5 to the fully opened state of the hopper 5, the optical axis O2 of the camera 30 tilts upward as it moves toward the rear of the vehicle. When the hopper 5 is fully opened, the lens 31 of the camera 30 is kept covered by the shutter unit 40. As a result, even if the ready-mixed concrete poured into the mixer drum 2 through the hopper 5 splashes, the shutter unit 40 prevents the ready-mixed concrete from adhering to the lens 31 of the camera 30.

[0048] The operation when the hopper 5 is closed from an open state is the reverse of the operation when it is opened from a closed state. When the hopper cover 6 is rotated in the closing direction from the fully open state of the hopper 5 until the shutter shaft 40A passes the position directly above the shaft 6A, the shutter unit 40 begins to rotate relatively in the opening direction due to gravity. When the hopper cover 6 is rotated in the closing direction by approximately 180° from the fully open state of the hopper 5 and the hopper 5 is completely closed, the shutter unit 40 opens the lens 31 of the camera 30 and puts it into an open state (see Figure 3). This enables the camera 30 to capture images of the ready-mixed concrete in the mixer drum 2.

[0049] In this way, the shutter section 40 is configured to automatically open and close the camera 30 by gravity as the hopper cover 6 is rotated. This makes it possible to protect the camera 30 from adhesion of ready-mixed concrete without having to remove the measurement unit 20 when pouring ready-mixed concrete.

[0050] If the measurement unit 20 is removed when pouring ready-mixed concrete, it is difficult to reproduce the installation position and posture when reattaching it, making it difficult to ensure the reproducibility of measurements. Therefore, when the measurement unit 20 is attached and detached when pouring ready-mixed concrete, the attachment and detachment work becomes complicated and the number of work steps increases. In contrast, in this embodiment, there is no need to remove the measurement unit 20 when pouring ready-mixed concrete, so the number of work steps can be reduced.

[0051] Furthermore, when the hopper 5 is opened, the shutter unit 40 normally rotates relative to the camera 30 in the blocking direction, but if the hopper cover 6 is rotated forcefully in the opening direction and then suddenly stopped, inertia may cause the shutter unit 40 to rotate in the opening direction, which is the opposite of the normal direction. In this case, if the shutter unit 40 moves beyond the position directly above the shutter shaft 40A in the opening direction, the camera 30 will be in an open state with the hopper 5 open, and gravity will prevent the shutter unit 40 from rotating in the direction that blocks the camera 30 (gravity will prevent it from returning to the state that blocks the camera 30).

[0052] In contrast, in this embodiment, the housing 21 is provided with a stopper portion 24. Therefore, even if the shutter portion 40 rotates in the opening direction due to inertia when the hopper 5 is opened, the stopper portion 24 and the shutter portion 40 abut against each other as shown in FIG. 6 . This prevents the shutter portion 40 from rotating in the opening direction until it can no longer return to the shielded state. Therefore, the camera 30 can be more reliably placed in the shielded state as the hopper cover 6 rotates in the opening direction. Furthermore, the stopper portion 24 protrudes forward in the optical axis direction of the camera 30 beyond the housing 21, and more desirably, protrudes rearward of the vehicle beyond the shutter shaft 40A when the hopper 5 is open. This more reliably prevents the shutter portion 40 from rotating in the opening direction, thereby more reliably placing the camera 30 in the shielded state.

[0053] Next, the open / close detection process executed by the control unit 50 will be described.

[0054] The open / close detection process detects whether the camera 30 is in a closed state or an open state by the shutter unit 40, and the detection result is displayed on the monitor.

[0055] The storage unit 52 stores a reference detection value based on at least one of the detection result (captured image) of the camera 30 in the blocked state and the detection result of the camera 30 in the open state. For example, the storage unit 52 stores the luminance value of a predetermined area (the entire area or a partial area of ​​the captured image) in the captured image captured in the blocked state as the detection result in the blocked state. Because the shutter unit 40 is a member having light-blocking properties, in the blocked state the captured image of the camera 30 appears dark and black, and a relatively low luminance value is stored as the reference detection value.

[0056] The control unit 50 receives the detection results of the camera 30 at predetermined time intervals. When the detection results of the camera 30 are received, the processing unit 51 acquires the average value of the luminance values ​​in a predetermined area in the captured image as the detection value. The processing unit 51 then compares the luminance value of the captured image with a reference luminance value to determine the state of the camera 30. If the luminance value in the captured image matches the detection reference value (is within a predetermined range of luminance values ​​including the detection reference value), the processing unit 51 determines that the camera 30 is in the blocked state; otherwise, it determines that the camera 30 is in the open state.

[0057] In this way, it is possible to detect the closed state and the open state of the camera 30 by comparing a detection reference value based on a detection value in at least one of the closed state and the open state with a detection value actually acquired by the camera 30. By detecting the closed state and the open state, it is possible to detect malfunctions in the opening and closing of the shutter unit 40 and prevent unintentional inability to acquire images by the camera 30 or to protect the camera 30. Note that in the open / close detection process, two detection reference values ​​based on both the closed state and the open state may be compared with the actual detection value of the camera 30, and the closed state and the open state may be detected depending on which one matches.

[0058] Next, a modification of this embodiment will be described.

[0059] In the above embodiment, the stopper portion 24 is a block body that is provided integrally with or separately from the housing 21. However, the stopper portion 24 may be formed of, for example, a spring (torsion spring, coil spring) or a shock absorber. This can cushion the momentum of the shutter portion 40 rotating in the opening direction and prevent the shutter portion 40 from opening the camera 30 when the hopper 5 is opened.

[0060] Furthermore, in the above embodiment, the shutter unit 40 is a plate member with a uniform thickness. However, for example, the shutter unit 40 may have a weight portion located radially away from the shutter shaft 40A. The weight portion may be formed by increasing the thickness of a portion of the shutter unit 40, or may be formed by attaching a separate member to the distal end of the shutter unit 40, with the shutter shaft 40A as the base end. By providing a weight portion located away from the shutter shaft 40A, the center of gravity of the shutter unit 40 is farther from the shutter shaft 40A than in the absence of the weight portion, making it easier for the shutter unit 40 to rotate around the shutter shaft 40A due to gravity. In other words, providing a weight portion makes it more difficult for the shutter unit 40 to move in the direction that opens the camera 30 when the hopper 5 is opened, thereby more reliably placing the camera 30 in a shielded state.

[0061] In the above embodiment, the sensor unit is the camera 30. However, the sensor unit is not limited to the camera 30, and may be an optical sensor such as an optical displacement meter.

[0062] The configuration, operation, and effects of the embodiment of the present invention will be described below.

[0063] In this embodiment, the mixer vehicle 101 comprises a mixer drum 2 rotatably mounted on the vehicle, and a state detection device 100 for detecting the state of the contents of the mixer drum 2. The mixer drum 2 has a hopper 5 for pouring the contents into it, and a hopper cover 6 that is rotatably attached to the hopper 5 via a shaft 6A and opens and closes the hopper 5. The state detection device 100 has a housing 21, a camera 30 that is attached to the hopper cover 6 via the housing 21 so as to be housed inside the hopper 5 when the hopper 5 is closed and detects the state of the contents, and a shutter unit 40 that is rotatably attached to the housing 21 via a shutter shaft 40A. The shutter unit 40 is configured to open the camera 30 without covering it when the hopper 5 is closed by the hopper cover 6, and to rotate around the shutter shaft 40A to cover the camera 30 as the hopper cover 6 rotates so that the hopper 5 changes from a closed state to an open state.

[0064] In addition, in this embodiment, the camera 30 is arranged so that the optical axis O2 extends downward of the vehicle toward the bottom of the mixer drum 2, and the shutter shaft 40A is arranged in the housing 21 so as to be positioned below the vehicle relative to the camera 30 when the hopper 5 is closed by the hopper cover 6.

[0065] Furthermore, in this embodiment, the condition detection device 100 that detects the condition of the contents in the mixer drum 2 includes a housing 21, a camera 30 that detects the condition of the contents and is attached to the hopper cover 6 via the housing 21 so as to be housed inside the hopper 5 when the hopper 5 is closed, and a shutter unit 40 that is rotatably attached to the housing 21 via a shutter shaft 40A, and is configured so that when the hopper 5 is closed by the hopper cover 6, the shutter unit 40 opens the camera 30 without covering it, and rotates around the shutter shaft 40A to cover the camera 30 as the hopper cover 6 rotates so that the hopper 5 changes from a closed state to an open state.

[0066] In these configurations, as the hopper cover 6 rotates about the shaft 6A from a closed state to an open state of the hopper 5, the shutter unit 40 rotates about the shutter shaft 40A due to gravity and covers the sensor unit. When the hopper 5 is in the open state, the camera 30 is covered by the shutter unit 40, which prevents the contents from adhering to the camera 30. This eliminates the need to remove the camera 30 from the hopper cover 6 every time the contents are added to the mixer drum 2.

[0067] Moreover, in this embodiment, the state detection device 100 further includes a stopper portion 24 that restricts the shutter portion 40 from rotating beyond a predetermined amount in the direction in which the camera 30 is opened.

[0068] With this configuration, when the hopper 5 is opened by the hopper cover 6, the shutter unit 40 can be prevented from rotating in the direction that opens the camera 30 due to the inertia of the rotation of the hopper cover 6. Therefore, the camera 30 can be more reliably covered by the shutter unit 40 when the hopper 5 is opened.

[0069] In this embodiment, the shutter section 40 is detachably attached to the housing 21.

[0070] In this configuration, even if the contents adhere to the shutter part 40, the shutter part 40 can be easily replaced.

[0071] In addition, in this embodiment, the state detection device 100 further includes a control unit 50 that processes the detection results of the camera 30, and the control unit 50 pre-stores at least one of the detection results of the camera 30 when the hopper 5 is closed and the shutter unit 40 covers the camera 30 and the detection result of the camera 30 when the hopper 5 is open and the shutter unit 40 opens the camera 30 as a reference detection value, and compares the reference detection value with the detection value detected by the camera 30 to detect the open / closed state of the shutter unit 40.

[0072] In this configuration, it is possible to confirm whether the camera 30 is opened or closed by the shutter unit 40.

[0073] Although the embodiments of the present invention have been described above, the above embodiments merely illustrate some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above embodiments. [Explanation of symbols]

[0074] 100... state detection device, 101... mixer vehicle, 2... mixer drum, 5... hopper, 6... hopper cover, 6A... shaft (cover rotation shaft), 21... housing, 24... stopper section, 30... camera (sensor section), 40... shutter section, 40A... shutter shaft (shutter rotation shaft), 50... control section

Claims

1. A mixer truck, a mixer drum rotatably mounted on the vehicle; a state detection device for detecting the state of the contents of the mixer drum; The mixer drum is a hopper for depositing the contents; a hopper cover that is rotatably attached to the hopper via a cover rotation shaft and opens and closes the hopper; The state detection device is The housing and a sensor unit attached to the hopper cover via the housing so as to be accommodated inside the hopper when the hopper is closed, and which acquires information indicating the state of the contents; a shutter unit rotatably attached to the housing via a shutter rotation shaft, The shutter section is configured to open the sensor section without covering it when the hopper cover is closed on the hopper, and to rotate about the shutter rotation axis to cover the sensor section when the hopper cover is rotated so that the hopper changes from a closed state to an open state.

2. The mixer vehicle according to claim 1, the sensor unit is provided such that a sensor axis extends downwardly toward a bottom of the mixer drum, The mixer truck is characterized in that the shutter rotation shaft is provided on the housing so as to be located below the sensor unit when the hopper is closed by the hopper cover.

3. The mixer vehicle according to claim 1 or 2, The mixer truck according to claim 1, wherein the state detection device further includes a stopper portion that restricts rotation of the shutter portion in a direction that opens the sensor portion by more than a predetermined amount.

4. The mixer vehicle according to claim 1 or 2, The mixer truck is characterized in that the shutter unit is detachably attached to the housing.

5. The mixer vehicle according to claim 1 or 2, the state detection device further includes a control unit that processes the detection result of the sensor unit; The control unit pre-stores, as a detection reference value, at least one of the detection result of the sensor unit when the hopper is closed and the shutter unit covers the sensor unit and the detection result of the sensor unit when the hopper is open and the shutter unit opens the sensor unit, and compares the detection reference value with the detection value detected by the sensor unit to detect the open / closed state of the shutter unit.

6. A state detection device for detecting the state of contents in a mixer drum of a mixer vehicle, the state detection device having a hopper for feeding contents into the mixer drum of the mixer vehicle, and a hopper cover rotatably attached to the hopper via a cover rotation shaft for opening and closing the hopper, The housing and a sensor unit attached to the hopper cover via the housing so as to be accommodated inside the hopper when the hopper is closed, and detecting the state of the contents; a shutter unit rotatably attached to the housing via a shutter rotation shaft, The shutter section is configured to open the sensor section without covering it when the hopper cover is closed on the hopper, and to rotate around the shutter rotation axis to cover the sensor section when the hopper cover is rotated so that the hopper changes from a closed state to an open state.

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