Work vehicle

Abstract

To provide a work vehicle which enables reduction of a possibility that a positioning device located on the upper side of a cabin contacts with an obstacle to be damaged and which reduces a user's workload.SOLUTION: A tractor 1 serving as a work vehicle includes: a vehicle body; a cabin 7 mounted on the vehicle body and having a roof 70; and an antenna unit 50 serving as a positioning device located on the upper side of the cabin 7 and configured to detect a position of the vehicle body on the basis of a signal transmitted from a positioning satellite. The roof 70 has a roof front end 70F located in a forefront portion in a front-rear direction. The roof 70 inclines so as to be higher toward the rear relative to the roof front end 70F. A position of the positioning device is higher than the roof front end 70F and lower than at least a part of the roof 70.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a work vehicle such as a tractor.

Background Art

[0002] Conventionally, a technique has been proposed in which a positioning device for detecting the position of a vehicle body is provided above the cab of a tractor (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the tractor of Patent Document 1, the roof of the cab is horizontal. Therefore, when a positioning device is installed above the cab, the positioning device protrudes above the roof of the cab. Therefore, when the tractor is driven with the positioning device installed, depending on the situation, the positioning device may come into contact with an obstacle and be damaged. For example, when storing the tractor in a shed, the positioning device above the cab may come into contact with the upper part of the shed entrance and be damaged.

[0005] In order to avoid damage to the positioning device due to contact with an obstacle, for example, it may be considered that the positioning device is rotated and changed to a lower position, or the positioning device is removed. However, in these cases, troublesome operations for changing the position or removing the positioning device are required, increasing the work burden on the user. Therefore, some improvement is needed regarding the installation of the positioning device.

[0006] The present invention has been made to solve the above problems, and an object thereof is to provide a work vehicle capable of reducing the risk of damage caused by contact between a positioning device located above the cabin and an obstacle, and capable of reducing the work load of a user.

Means for Solving the Problems

[0007] A work vehicle according to an aspect of the present invention is a work vehicle including a vehicle body and a cabin mounted on the vehicle body and having a roof, and includes a positioning device that is located above the cabin and detects the position of the vehicle body based on a signal transmitted from a positioning satellite. The roof has a roof front end located at the foremost part in the front-rear direction, the roof is inclined so as to be higher toward the rear than the roof front end, and the position of the positioning device is higher than the roof front end and lower than at least a part of the roof.

Effects of the Invention

[0008] According to the above configuration, it is possible to reduce the risk of damage caused by contact between the positioning device located above the cabin and an obstacle, and it is possible to reduce the work load of the user.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Embodiments for Carrying Out the Invention

[0010] Embodiments of the present invention will be described as follows with reference to the drawings. In this embodiment, a tractor will be described as an example of a work vehicle. However, as work vehicles, in addition to tractors, it is also possible to consider riding work vehicles such as rice transplanters, combines, civil engineering and construction work equipment, and snow removal vehicles.

[0011] Also, in this specification, directions are defined as follows. First, the direction in which a tractor as a work vehicle travels during work is defined as "front", and the opposite direction is defined as "rear". Also, the right side is defined as right and the left side is defined as left toward the traveling direction of the tractor. And the direction perpendicular to the front-rear direction and the left-right direction of the tractor is defined as the vertical direction. At this time, the direction of gravity is defined as down, and the opposite side is defined as up.

[0012] 〔1. Outline of Vehicle Traveling System〕 FIG. 1 is a side view showing a schematic configuration of a tractor 1 which is an example of a work vehicle according to this embodiment. FIG. 2 is a block diagram of a vehicle traveling system including the tractor 1.

[0013] As shown in FIG. 2, the vehicle driving system of the present embodiment includes a tractor 1, a wireless communication terminal 30, and a reference station 40. The tractor 1 can travel according to the operation of the driver, or can autonomously travel based on instructions from the wireless communication terminal 30 or the like. The wireless communication terminal 30 is a terminal for giving various instructions to the tractor 1. The reference station 40 is provided to acquire the position information of the tractor 1.

[0014] As shown in FIG. 1, the tractor 1 includes a vehicle body 2. It is possible to mount a ground working machine (not shown) on the rear side of the vehicle body 2. As the ground working machine, for example, a tilling device, a plow, or a fertilizer applicator can be used, but it is not limited thereto.

[0015] The front part of the vehicle body 2 is supported by a pair of left and right front wheels 3. The rear part of the vehicle body 2 is supported by a pair of left and right rear wheels 4. A bonnet 5 is arranged at the front part of the vehicle body 2. An engine 6 as a drive source is arranged below the bonnet 5. The engine 6 is, for example, a diesel engine, but is not limited thereto, and may be, for example, a gasoline engine. Further, in addition to or instead of the engine 6, an electric motor may be used as the drive source.

[0016] A cabin 7 for the operator (driver) to board is provided on the upper part of the vehicle body 2 behind the bonnet 5. A door 7a that opens forward and rotates is provided on the left side of the cabin 7. By opening and closing the door 7a, the driver can get on and off the cabin 7. Note that the door 7a may be provided on the right side of the cabin 7.

[0017] The cabin 7 has a roof 70. That is, the tractor 1 as a work vehicle includes a vehicle body 2 and a cabin 7 mounted on the vehicle body 2 and having a roof 70. Inside the cabin 7, a steering wheel 8 for the driver to perform a steering operation and a driver's seat 9 are provided.

[0018] On the rear side of the vehicle body 2, a three-point link mechanism is provided. The three-point link mechanism includes a pair of left and right lower links 10 and an upper link 11. The above-mentioned ground working machine is configured to be attachable to the three-point link mechanism. Further, on the rear side of the vehicle body 2, a lifting device (not shown) having a hydraulic device such as a lifting cylinder is provided. By the lifting device lifting the three-point link mechanism, the ground working machine can be lifted and lowered.

[0019] As shown in FIG. 2, the tractor 1 is provided with a governor device 21 capable of adjusting the rotational speed of the engine 6 and a transmission device 22 that changes the rotational driving force from the engine 6 and transmits it to the drive wheels. The governor device 21 and the transmission device 22 are controlled by a control unit 23.

[0020] The tractor 1 is equipped with a steering device 24. The steering device 24 is provided, for example, in the middle part of the rotation axis of the steering wheel 8 and is configured to be able to adjust the rotation angle (steering angle) of the steering wheel 8. By the control unit 23 controlling the steering device 24, the tractor 1 can not only travel straight, but also adjust the rotation angle of the steering wheel 8 to a desired angle and perform turning travel with a desired turning radius.

[0021] The tractor 1 further includes an antenna unit 50. The antenna unit 50 is located above the cabin 7 (especially the roof 70) and is a positioning device that detects the position of the vehicle body 2 based on the signal transmitted from the positioning satellite (navigation satellite) 45 shown in FIG. 1.

[0022] The antenna unit 50 and the control unit 23 are electrically connected by a harness WH. Thereby, various kinds of information or instructions can be transmitted between the antenna unit 50 and the control unit 23 via the harness WH. For example, the position information of the vehicle body 2 detected by the antenna unit 50 is input to the control unit 23 via the harness WH. From this, it can be said that the tractor 1 includes a control unit 23 to which the position information of the vehicle body 2 detected by the antenna unit 50 is input via the harness WH.

[0023] Next, the details of the above-described antenna unit 50 will be explained. The antenna unit 50 includes an inertial measurement unit (IMU) 25, a GNSS (Global Navigation Satellite System) antenna 26, a wireless communication unit 27, an antenna 28 for wireless communication, and a base station antenna 29.

[0024] The inertial measurement unit 25 includes a three-axis gyro sensor and a three-directional accelerometer, thereby detecting three-dimensional angular velocity and acceleration. The detection values of the inertial measurement unit 25 are input to the control unit 23. Based on the above detection values, the control unit 23 can obtain the attitude information of the tractor 1. The above attitude information includes, for example, information on the azimuth angle (yaw angle) of the aircraft body, the left and right inclination angles (roll angles) of the aircraft body, and the front and rear inclination angles (pitch angles) in the traveling direction of the aircraft body.

[0025] The GNSS antenna 26 receives radio wave signals transmitted from positioning satellites 45 that constitute a satellite positioning system (GNSS). In the satellite positioning system, in addition to GPS (Global Positioning System; United States) as a positioning satellite, quasi-zenith satellites (Japan), Glonass satellites (Russia), etc. can be used.

[0026] The wireless communication unit 27 transmits and receives various signals via a wireless communication network constructed with a wireless communication terminal 30 or the like. In the present embodiment, the wireless communication unit 27 is composed of a Wi-Fi (registered trademark) unit with a frequency band of 2.4 GHz. The signal transmitted from the wireless communication terminal 30 is received by the antenna 28 for wireless communication and input to the control unit 23 via the wireless communication unit 27. Also, the signal from the control unit 23 is transmitted to the wireless communication device 31 or the like of the wireless communication terminal 30 via the wireless communication unit 27 and the antenna 28 for wireless communication.

[0027] Here, as a positioning method using a satellite positioning system, in this embodiment, for example, RTK (Real Time Kinematic) positioning is used. In RTK positioning, the carrier phase (satellite positioning information) from the positioning satellite 45 is measured by both the reference station antenna 42 for reference station positioning of the reference station 40 installed at the reference point and the GNSS antenna 26 on the tractor 1 side which is the target for obtaining position information. At the reference station 40, correction information is generated each time satellite positioning information is measured from the positioning satellite 45 or each time a set period elapses. The above correction information is transmitted from the reference station wireless communication device 41 to the base station antenna 29 of the tractor 1. The control unit 23 of the tractor 1 corrects the satellite positioning information measured by the GNSS antenna 26 using the correction information transmitted from the reference station 40, and obtains the current position information of the tractor 1. The control unit 23 obtains, for example, latitude information and longitude information as the current position information of the tractor 1.

[0028] Note that the positioning method to be used is not limited to the above RTK positioning, and other positioning methods such as DGPS (Differential GPS positioning) may be used. Also, the reference station 40 can transmit and receive various types of information not only with the tractor 1 but also with the wireless communication terminal 30.

[0029] The wireless communication terminal 30 is composed of, for example, a tablet-type personal computer having a touch panel. The wireless communication terminal 30 is provided with a wireless communication device 31 and a route generation unit 32 for generating a target travel route. The route generation unit 32 can generate a target travel route for autonomously driving the tractor 1 based on various types of information input through the touch panel. The route generation unit 32 is composed of, for example, a CPU (Central Processing Unit) of a personal computer.

[0030] The wireless communication terminal 30 transmits various types of information for autonomously driving the tractor 1, such as the target travel route, to the tractor 1. The control unit 23 of the tractor 1 obtains the current position information of the tractor 1 from the received signal of the GNSS antenna 26, and obtains the displacement information and azimuth information of the vehicle body 2 from the detected values of the inertial measurement unit 25. Based on these pieces of information, by controlling the transmission device 22, the steering device 24, etc., the tractor 1 can be autonomously driven along the target travel route generated by the route generation unit 32.

[0031] [2. Installation method of the antenna unit (Part 1)] Next, the installation method of the above-described antenna unit 50 will be described. FIG. 3 is a side view of the upper part of the cabin 7 of the tractor 1. FIG. 4 is a perspective view of the cabin 7 of the tractor 1 when viewed from above. First, the shape of the roof 70 of the cabin 7 will be described.

[0032] The roof 70 of the cabin 7 has a roof front end 70F. The roof front end 70F is located at the most forward side of the roof 70 in the front-rear direction. That is, the roof 70 has a roof front end 70F located at the foremost part in the front-rear direction.

[0033] More specifically, the cabin 7 has a right front pillar 71R and a left front pillar 71L. The right front pillar 71R and the left front pillar 71L are connected to the vehicle body 2 and support the right front part and the left front part of the roof 70, respectively. That is, the cabin 7 has a right front pillar 71R that is connected to the vehicle body 2 and supports the right front part of the roof 70, and a left front pillar 71L that is connected to the vehicle body 2 and supports the left front part of the roof 70. The above-described roof front end 70F is located at the most forward side at the peripheral edge of the roof 70 connecting the upper ends of the right front pillar 71R and the left front pillar 71L.

[0034] In the present embodiment, the cabin 7 has a front glass FG in front of the driver's seat 9 (see FIG. 1). In this configuration, the roof front end 70F coincides with the most forward position in the roof 70 where it contacts the upper side of the front glass FG.

[0035] Note that the cabin 7 does not necessarily have a windshield FG. Even if the cabin 7 is configured without a windshield, at the peripheral edge of the roof 70 connecting the upper ends of the right front pillar 71R and the left front pillar 71L, the most forward - located portion becomes the roof front end 70F.

[0036] The roof 70 of the cabin 7 further has a roof uppermost end 70H. The roof uppermost end 70H is the highest - located portion in the roof 70. This roof uppermost end 70H is located behind the roof front end 70F. In the present embodiment, the roof uppermost end 70H is located slightly rearward of the central portion in the front - rear direction of the roof 70. Note that the position of the roof uppermost end 70H is not limited to the above - described position. For example, the roof uppermost end 70H may coincide with the position of the roof rear end 70R, which is the most rear - side position of the roof 70 in the front - rear direction. In any case, the roof 70 has a shape (streamlined shape) in which the roof upper surface slopes downward in a gradient from the roof uppermost end 70H toward the front. Thus, the roof 70 is located behind the roof front end 70F and has a roof uppermost end 70H that is higher in position than the roof front end 70F.

[0037] As shown in FIG. 3, the position of the antenna unit 50 as a positioning device is lower than the roof uppermost end 70H above the cabin 7 (particularly the roof 70). Note that such a position of the antenna unit 50 can be realized by using a support mechanism 100 or a support stay 200 (see FIG. 5), etc. Details of the support mechanism 100, etc. will be described later.

[0038] In the tractor 1 of the present embodiment, the roof 70 of the cab 7 is not horizontal and has a roof uppermost end 70H that is higher in position than the roof front end 70. For this reason, the antenna unit 50 can be installed above the cab 7 and at a position lower than the roof uppermost end 70H. At such a position of the antenna unit 50, since the antenna unit 50 does not protrude above the roof uppermost end 70H, even when the tractor 1 is driven with the antenna unit 50 installed above the cab 7, there is no risk of the antenna unit 50 colliding with surrounding obstacles. As a result, damage due to contact between the antenna unit 50 and obstacles can be reduced. Also, in order to avoid contact between the antenna unit 50 and obstacles, troublesome operations such as the user (for example, the driver of the tractor 1) removing the antenna unit 50 from the cab 7 or changing the antenna unit 50 to a lower position by rotation or the like are not required. Therefore, the work burden on the user can also be reduced.

[0039] Note that as the above-mentioned obstacles, for example, (1) the upper part of the entrance and exit of the storage shed when storing the tractor 1 in the storage shed, (2) the roof of the truck bed when loading the tractor 1 onto the truck bed (with a roof) for transporting the tractor 1, (3) the lower part of the elevated structure when the tractor 1 travels under an elevated structure such as a railway, etc. can be considered.

[0040] Also, in the present embodiment, as shown in FIG. 3, the antenna unit 50 is located between the roof front end 70F and the roof uppermost end 70H. That is, the position of the antenna unit 50 is higher than the roof front end 70F.

[0041] At such a position of the antenna unit 50, it is possible to reduce the risk that the line of sight from the front to above as seen by the driver boarding in the cab 7 is blocked by the antenna unit 50. As a result, a good line of sight for the driver can be ensured. That is, it is possible to reduce the situation where the visibility during the driver's work (during operation) is reduced due to the installation of the antenna unit 50.

[0042] In addition, in this embodiment, as shown in FIG. 3, the antenna unit 50 is positioned in front of the uppermost roof end 70H. As described above, in a roof shape where the position of the uppermost roof end 70H is higher than the roof front end 70F and has a downward gradient from the uppermost roof end 70H toward the front, by positioning the antenna unit 50 in front of the uppermost roof end 70H, it becomes easy to position the antenna unit 50 at a position lower than the uppermost roof end 70H.

[0043] Note that in a shape where the roof rear end 70R is lower than the uppermost roof end 70H, by appropriately setting the height difference between the uppermost roof end 70H and the roof rear end 70R, it is also possible to install the antenna unit 50 behind the uppermost roof end 70H and at a position lower than the uppermost roof end 70H.

[0044] Next, the details of the above-described support mechanism 100 will be described. The tractor 1 includes a support mechanism 100 that supports the antenna unit 50. This support mechanism 100 includes a right stay 101R and a left stay 101L, a support pipe 102 that is a support member, and a pedestal 103.

[0045] The right stay 101R is attached to the right front pillar 71R. The right stay 101R supports a mirror (not shown) via a mirror support rod 101a. The left stay 101L supports a work lamp WL and also supports a mirror M via a mirror support rod 101a. Note that the right stay 101R may support a work lamp in the same manner as the left stay 101L. Thus, the support mechanism 100 includes a right stay 101R and a left stay 101L that are respectively attached to the right front pillar 71R and the left front pillar 71L.

[0046] The attachment of the right stay 101R to the right front pillar 71R and the attachment of the left stay 101L to the left front pillar 71L are performed, for example, by welding, but may also be performed by other methods such as fixing with bolts. Further, a radio antenna (not shown) may be detachably provided on the right stay 101R or the left stay 101L.

[0047] The support pipe 102 extends horizontally above the roof 70 and bends downward near both left and right ends. The right end of the support pipe 102 is attached to the right stay 101R. The left end of the support pipe 102 is attached to the left stay 101L. The attachment of the support pipe 102 to the right stay 101R and the left stay 101L may be performed using fasteners such as bolts, or may be performed using dedicated mounting brackets (e.g., clamp brackets). In this embodiment, the support pipe 102 is bent slightly rearward at the central portion in the horizontal direction above the roof 70, but may be straight in the horizontal direction without bending.

[0048] The pedestal 103 is located above the roof and at the central portion in the horizontal direction, and is fixed to the support pipe 102. The support pipe 102 and the pedestal 103 are fixed, for example, by welding, but may be removably fixed using fasteners such as bolts. The pedestal 103 supports the antenna unit 50 from below. The antenna unit 50 is fixed to the pedestal 103, for example, by tightening bolts.

[0049] Thus, the support mechanism 100 has a support pipe 102 that extends horizontally above the roof 70 and has both ends fixed to the right stay 101R and the left stay 101L, and a pedestal 103 that is fixed to the support pipe 102 above the roof 70. And the antenna unit 50 is fixed to the pedestal 103.

[0050] In the configuration of the support mechanism 100 described above, the pedestal 103 to which the antenna unit 50 is fixed is fixed to the support pipe 102 above the roof 70. Both ends of the support pipe 102 are respectively fixed to the right stay 101R and the left stay 101L. The right stay 101R and the left stay 101L are respectively attached to the right front pillar 71R and the left front pillar 71L. Therefore, by fixing the antenna unit 50 to the pedestal 103, the antenna unit 50 can be stably supported above the roof 70. Also, by using the support mechanism 100, it is possible to easily perform the after - attachment of the antenna unit 50 to the tractor 1.

[0051] Also, in the present embodiment, as shown in FIG. 4, a harness WH that electrically connects the antenna unit 50 and the control unit 23 (see FIG. 2) is arranged along the right front pillar 71R. Note that the harness WH may be arranged along the left front pillar 71L. That is, the harness WH is arranged along the right front pillar 71R or the left front pillar 71L. Thereby, it becomes easy to route (wire) the exposed harness WH without making it conspicuous.

[0052] Also, when a door 7a (see FIG. 1) is provided on the left side of the cabin 7 as in the present embodiment, if the harness WH is arranged along the left front pillar 71L, there is a risk that the harness WH may come into contact with the door when the door 7a is opened or closed, or the harness WH may be pinched by the door 7a. From the viewpoint of avoiding such inconveniences, it is desirable that the harness WH be arranged along the right front pillar 71R. That is, it is desirable that the harness WH be arranged along the pillar that is located on the side opposite to the entrance / exit (door 7a) of the cabin 7 in the left-right direction among the right front pillar 71R and the left front pillar 71L.

[0053] 〔3. Installation method of antenna unit (Part 2)〕 The antenna unit 50 of the present embodiment can also be fixed to the roof 70 of the cabin 7 using a support stay 200 shown in FIG. 5 instead of the support mechanism 100 described above. Hereinafter, another installation method of the antenna unit 50 will be described. Note that even when the support stay 200 is used, the point that the antenna unit 50 can be positioned above the cabin 7 and at a position lower than the uppermost end 70H of the roof is the same as the case when the support mechanism 100 is used.

[0054] FIG. 5 is a side view of the upper part of the cabin 7 of the tractor 1 in which the antenna unit 50 is installed on the roof 70 using the support stay 200. FIG. 6 is a perspective view of the cabin 7 of the tractor 1 in FIG. 5 when viewed from above. Further, FIG. 7 is a perspective view of the cabin 7 with the illustration of the antenna unit 50 in FIG. 6 omitted.

[0055] The support stay 200 is fixed to the upper surface of the roof 70 (particularly the outer roof 703 (see FIG. 9) described later). The fixing of the support stay 200 to the roof 70 is performed using the fastener 80, and the details of the fixing method will be described later. The antenna unit 50 is fixed to and supported by the support stay 200 (particularly the flat plate portion 201a and the auxiliary stay 202) described later by bolts or the like. Thereby, the antenna unit 50 is positioned above the roof 70. That is, the tractor 1 is fixed to the upper surface of the roof 70 and includes the support stay 200 that supports the antenna unit 50.

[0056] The support stay 200 that supports the antenna unit 50 is fixed to the upper surface of the roof 70. Thereby, the antenna unit 50 can be stably positioned above the roof 70.

[0057] The support stay 200 has a stay main body 201 and an auxiliary stay 202. The stay main body 201 is formed in a long shape in the left-right direction and is positioned above the roof 70. That is, the support stay 200 has a stay main body 201 that extends in the left-right direction above the roof 70.

[0058] The stay main body 201 has a flat plate portion 201a and a hanging portion 201b. The flat plate portion 201a is formed in a long shape in the left-right direction and supports the antenna unit 50 from below at the central portion in the left-right direction. The hanging portion 201b is formed in a long shape in the left-right direction and hangs downward from the front end portion 201a1 (see FIG. 8) of the flat plate portion 201a. As a result, the stay main body 201 is in an inverted L shape in side view. Note that the hanging portion 201b may be formed to hang downward from the rear end portion 201a2 (see FIG. 8) of the flat plate portion 201a. The stay main body 201 having the flat plate portion 201a and the hanging portion 201b can be formed by bending a single metal plate at 90°, or may be formed by connecting the flat plate portion 201a and the hanging portion 201b by welding or the like.

[0059] Thus, the stay body 201 has a flat plate portion 201a that extends in the left - right direction and supports the antenna unit 50 from below, and a hanging portion 201b that extends in the left - right direction and hangs down from the front end portion 201a1 or the rear end portion 201a2 of the flat plate portion 201a.

[0060] The auxiliary stay 202 is fixed to the front side of the hanging portion 201b by welding or the like in order to assist the support of the antenna unit 50 by the stay body 201. The auxiliary stay 202 has an inverted L - shaped cross - section and has a support surface 202a for supporting the antenna unit 50. In the vertical direction, the position of the support surface 202a substantially coincides with the position of the upper surface of the flat plate portion 201a.

[0061] In the present embodiment, the auxiliary stays 202 are provided at two positions spaced apart in the left - right direction at the center in the left - right direction of the hanging portion 201b. However, the number of the auxiliary stays 202 may be one, or may be three or more as required. Also, the auxiliary stay 202 is not an essential component, and it is also possible to omit the installation of the auxiliary stay 202.

[0062] Next, the details of the method for fixing the support stay 200 to the roof 70 will be described. FIG. 8 is a perspective view schematically showing the vicinity of the fixing portion of the support stay 200 on the roof 70. Also, FIG. 9 is a cross - sectional view when the support stay 200 and the roof 70 are cut along the plane passing through the roof fixing bolt 81 in FIG. 8. In FIG. 8, for the sake of convenience, the illustration of the inner roof 701 and the outer roof 703 shown in FIG. 9 is omitted.

[0063] The roof 70 has an inner roof 701, a fixed frame 702, and an outer roof 703. The inner roof 701 is located on the indoor side of the cabin 7 in the roof 70. The inner roof 701 is fixed to the fixed frame 702 by fixing members (such as stays, bolts, nuts, etc.) not shown in the figure. The outer roof 703 is disposed above the inner roof 701 and fixed to the fixed frame 702. That is, the roof 70 has an inner roof 701, a fixed frame 702 to which the inner roof 701 is fixed, and an outer roof 703 disposed above the inner roof 701.

[0064] Here, the fastening unit 80 used when only the outer roof 703 is fixed to the fixed frame 702 (see FIG. 8) will be described first. FIG. 10 is a cross-sectional view of the fastening unit 80. The fastening unit 80 includes a roof fixing bolt 81, a rubber washer 82, a connecting stay 83, and a nut 84.

[0065] The rubber washer 82 is provided to prevent rainwater from entering the cabin 7 from above the roof 70. An opening 82a through which the roof fixing bolt 81 is inserted is provided at the center of the rubber washer 82.

[0066] The connecting stay 83 is a metal plate for connecting the outer roof 703 and the fixed frame 702 and has a shape bent at a predetermined position. A through hole 83a is provided in the connecting stay 83. The roof fixing bolt 81 is inserted through the through hole 83a. The connecting stay 83 is fixed to the fixed frame 702 by welding or the like at a portion spaced apart from the through hole 83a (see FIG. 8). A through hole 703a through which the roof fixing bolt 81 is inserted is provided in the outer roof 703.

[0067] Therefore, as shown in FIG. 10, the roof fixing bolt 81 is inserted into the opening 82a of the rubber washer 82, the through hole 703a of the outer roof 703, and the through port 83a of the connecting stay 83 in this order from above, and is screwed with the nut 84, whereby the outer roof 703 can be fixed to the fixing frame 702. The outer roof 703 is fixed to the fixing frame 702 at a plurality of locations by the fastening unit 80. Note that the above-mentioned screwing means rotating the bolt to engage with the nut.

[0068] The support stay 200 can be easily fixed to the roof 70 by using the above-mentioned fastening unit 80 in combination with a spacer bolt 85 which is a spacer member shown in FIGS. 8 and 9.

[0069] The spacer bolt 85 has a convex portion 85a at the lower end portion in the rotation axis direction. The convex portion 85a passes through the opening 82a of the rubber washer 82, the through hole 703a of the outer roof 703, and the through port 83a of the connecting stay 83, and is screwed with the nut 84. Further, the spacer bolt 85 has a concave portion 85b at the upper end portion in the rotation axis direction. A screw groove is cut on the inner surface of the concave portion 85b, and the roof fixing bolt 81 is inserted and screwed therein.

[0070] On the other hand, a through hole 201p is provided in the flat plate portion 201a of the stay body 201 of the support stay 200. The support stay 200 can be fixed to the spacer bolt 85 by inserting the roof fixing bolt 81 into the through hole 201p and further screwing it into the concave portion 85b of the spacer bolt 85.

[0071] Therefore, by using the spacer bolt 85, the support stay 200 can be held at a predetermined height position spaced upward from the outer roof 703 by the height of the spacer bolt 85. Note that the height of the spacer bolt 85 may be appropriately set according to the target height position above the roof 70 of the antenna unit 50. Further, by inserting the convex portion 85a of the spacer bolt 85 into the opening 82a of the rubber washer 82, the through hole 703a of the outer roof 703, and the through port 83a of the connecting stay 83 in order from above and screwing it with the nut 84, the support stay 200 fixed to the spacer bolt 85 can be fixed to the fixing frame 702 together with the outer roof 703.

[0072] In this way, the outer roof 703 is connected to the fixing frame 702 by the fastening unit 80. The fastening unit 80 includes a spacer bolt 85 that holds the support stay 200 at a predetermined height position with respect to the outer roof 703.

[0073] In this way, since the fastening unit 80 includes the spacer bolt 85, the support stay 200 can be easily fixed to the upper surface of the roof 70 by the spacer bolt 85 while effectively using the normal fastening unit 80 that fixes the outer roof 703 to the fixing frame 702. Therefore, for example, when fixing the support stay 200 to the roof 70, the operation of separately providing a dedicated hole for fixing the support stay 200 on the upper surface of the roof 70 can be made unnecessary.

[0074] Further, in the present embodiment, as shown in FIG. 7 and the like, the stay body 201 is fixed to the roof 70 (particularly the outer roof 703) by the fastening unit 80 at its right end and left end. That is, each end portion of the stay body 201 in the left-right direction is fixed to the outer roof 703 by the fastening unit 80 including the spacer bolt 85. Thereby, the support stay 200 extending in the left-right direction can be stably fixed to the outer roof 703.

[0075] Also, as shown in FIG. 6, in the configuration where the antenna unit 50 is supported by the flat plate portion 201a of the support stay 200, it is desirable that the harness WH for electrically connecting the antenna unit 50 and the control unit 23 (see FIG. 2) is drawn out in the lateral direction from behind the hanging portion 201b of the antenna unit 50.

[0076] By positioning the harness WH behind the hanging portion 201b of the support stay 200, the hanging portion 201b serves as a cover for the routing of the harness WH when viewed from the front. Therefore, it is possible to reduce the situation where the appearance quality is impaired due to the exposure of the harness WH.

[0077] As described above, the embodiments of the present invention have been described. However, the scope of the present invention is not limited thereto, and it can be implemented with expansion or modification without departing from the gist of the invention.

Industrial Applicability

[0078] The present invention can be used for work vehicles such as tractors, for example.

Explanation of Reference Numerals

[0079] 1 Tractor (work vehicle) 2 Vehicle body 23 Control unit 7 Cabin 45 Positioning satellite 50 Antenna unit (positioning device) 70 Roof 70F Front end of roof 70H Top end of roof 71R Right front pillar 71L Left front pillar 80 Fastening unit 85 Spacer bolt (spacer member) 100 Support mechanism 101R Right stay 101L Left stay 102 Support pipe (support member) 103 Pedestal 200 Support stay 201 Main Body 201a Flat Part 201b Vertical Part 701 Inner Roof 702 Fixed Frame 703 Outer Roof WH Harness

Claims

1. A work vehicle comprising a vehicle body and a cabin mounted on the vehicle body and having a roof, wherein the work vehicle is provided with a positioning device located above the cabin and configured to detect the position of the vehicle body based on signals transmitted from positioning satellites, the roof has a roof front end located at the foremost part in the front-rear direction, the roof is inclined so as to rise rearward from the roof front end, and the position of the positioning device is higher than the roof front end and lower than at least a part of the roof.

2. The work vehicle according to claim 1, wherein the positioning device has a GNSS antenna as a receiving unit, and the position of the GNSS antenna is lower than at least a part of the roof.

3. The work vehicle according to claim 1 or 2, wherein the positioning device is located forward of the uppermost end of the roof.

4. The work vehicle further comprises a support mechanism for supporting the positioning device, the cabin has a right front pillar connected to the vehicle body and supporting the right front part of the roof and a left front pillar connected to the vehicle body and supporting the left front part of the roof, the support mechanism has a right stay and a left stay respectively attached to the right front pillar and the left front pillar, a support member extending in the left-right direction above the roof and having both ends fixed to the right stay and the left stay, and a pedestal fixed to the support member above the roof, and the positioning device is fixed to the pedestal.

5. The work vehicle according to claim 4 further comprises a control unit into which the position information of the vehicle body detected by the positioning device is input via a harness, and the harness is arranged along the right front pillar or the left front pillar.

6. The work vehicle according to any one of claims 1 to 3 further comprises a support stay fixed to the upper surface of the roof and supporting the positioning device.

7. The roof has an inner roof, a fixed frame to which the inner roof is fixed, and an outer roof arranged above the inner roof, the outer roof is connected to the fixed frame by a fastening unit, and the fastening unit includes a spacer member for holding the support stay at a predetermined height position with respect to the outer roof.

8. The support stay has a stay body extending in the left-right direction above the roof. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The work vehicle according to claim 7, wherein each end portion in the left - right direction of the stay main body is fixed to the outer loop by the fastening unit including the spacer member.

9. The work vehicle further includes a control unit to which the position information of the vehicle body detected by the positioning device is input via a harness. The stay main body has a flat plate portion that extends in the left - right direction and supports the positioning device from below, and a hanging portion that extends in the left - right direction and hangs down from the front end portion or the rear end portion of the flat plate portion. The work vehicle according to claim 8, wherein the harness is drawn out in the left - right direction behind the hanging portion from the positioning device.

Images