Paddy field farming machine

Abstract

To stabilize support of a step in a paddy field work machine in which a rear axle case supporting a rear wheel for traveling is supported by a machine body via a suspension spring.SOLUTION: A paddy field work machine includes: a spring receiving member 33 attached to a rear portion of a machine body frame 3; a rear axle case 27; and a suspension spring 34 attached across the spring receiving member 33 and the rear axle case 27. The paddy field work machine further includes a step frame 66 supporting a step from a lower side and a vertical frame 15 attached to the spring receiving member 33 and extending upward from the spring receiving member 33. The step frame 66 is attached to an upper portion of the vertical frame 15.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a paddy field working machine such as a riding rice transplanter or a riding direct seeding machine. [Background technology]

[0002] In a riding rice transplanter, which is an example of a paddy field work machine, as disclosed in Patent Document 1, a seedling planting device (corresponding to a work device) is supported on a link mechanism that extends rearward from the rear of the machine body, and a large step is provided at the rear of the machine body. Since the worker stands on the step to supply seedlings to the seedling planting device, if the step is configured to be large, it becomes easier to supply seedlings to the seedling planting device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-13759 Summary of the Invention [Problem to be solved by the invention]

[0004] In some paddy field working machines, the rear axle case that supports the rear wheels for driving is supported on the machine body via suspension springs. The present invention aims to stabilize support of steps in a paddy field working machine in which a rear axle case that supports the rear wheels for driving is supported on the machine body via suspension springs. [Means for solving the problem]

[0005] The paddy field working machine of the present invention comprises a body frame arranged along the front-rear direction, a spring bearing member attached to the rear of the body frame, a rear axle case supporting the rear wheels for traveling, a suspension spring attached across the spring bearing member and the rear axle case, a step provided at the rear of the body frame, and a step frame supporting the step from below, Partially A vertical frame is provided that is arranged to overlap the spring support member, is attached to the spring support member, and extends upward from the spring support member, and the step frame is attached to the upper part of the vertical frame.

[0006] According to the present invention, the rear of the vehicle frame is supported via the rear wheels, the rear axle case, and the suspension springs. The vertical frame is directly supported by the spring bearing members of the suspension springs, and the step frames that support the steps are supported by the vertical frame. As a result, the step and step frame are directly supported by the suspension spring via the vertical frame, so that the support of the step and step frame can be stabilized.

[0007] According to the present invention, when an impact from the ground during driving is transmitted to the vehicle frame via the rear wheel, rear axle case, and suspension spring, the impact from the ground is also transmitted to the vertical frame via the spring support member, dispersing the impact from the ground and thereby improving the strength of the vehicle frame. The vertical frame can be said to be an existing component used to position the step higher than the floor, so by effectively utilizing the existing vertical frame, it is advantageous in terms of simplifying the structure.

[0008] In the present invention, it is preferable that the lower portion of the vertical frame is attached across the spring receiving member and the vehicle frame.

[0009] According to the present invention, the lower part of the vertical frame is attached across the spring support member and the aircraft frame, so that the vertical frame acts as a reinforcing member for the attachment between the spring support member and the aircraft frame, which is advantageous in terms of improving the strength of the aircraft frame and the spring support member.

[0010] In the present invention, it is preferable that the spring receiving member has a main body portion attached to the lower part of the body frame so as to extend rightward from the right side of the body frame and extend leftward from the left side of the body frame, a right mounting portion attached across the part of the main body portion extending rightward from the right side of the body frame and the right side of the body frame, and a left mounting portion attached across the part of the main body portion extending leftward from the left side of the body frame and the left side of the body frame.

[0011] According to the present invention, the spring bearing member has a main body and right and left mounting portions, and is attached to the lower part and the right and left side portions of the vehicle frame. This improves the mounting strength of the spring bearing member to the vehicle frame, which is advantageous in terms of improving the strength of the vehicle frame and the spring bearing member.

[0012] In the present invention, it is preferable that the lower part of the vertical frame is attached across the upper part of the aircraft frame, the side of the aircraft frame, and the part of the main body extending from the side of the aircraft frame, thereby being attached across the spring support member and the aircraft frame.

[0013] According to the present invention, the lower part of the vertical frame is attached across the spring support member and the aircraft frame, so that the vertical frame acts as a reinforcing member for the attachment between the spring support member and the aircraft frame, which is advantageous in terms of improving the strength of the aircraft frame and the spring support member. By attaching the lower part of the vertical frame to the upper part of the body frame, the load applied from the step and step frame to the vertical frame is applied smoothly to the body frame, which is advantageous in terms of improving the support strength of the step and step frame.

[0014] In the present invention, it is preferable that a floor is provided on the body frame, the step is provided at a position higher than the floor, a floor frame supporting the floor from below is provided on the body frame, and a right connecting frame is attached in the vertical direction between the right front part of the step frame and the right rear part of the floor frame, and a left connecting frame is attached in the vertical direction between the left front part of the step frame and the left rear part of the floor frame.

[0015] According to the present invention, when a floor frame that supports the floor from below is provided on the aircraft frame, right and left connecting frames are attached across the right front and left front portions of the step frame and the right rear and left rear portions of the floor frame, which is advantageous in terms of improving the support strength of the step frame and the floor frame.

[0016] In the present invention, it is preferable that a fuel tank is provided below the right front portion or below the left front portion of the step frame, and that the right or left connecting frame is arranged in a vertical direction at a position laterally outside the fuel tank.

[0017] In paddy field working machines, a fuel tank may be provided below the right front portion or the left front portion of the step (step frame). According to the present invention, the right or left connecting frame is positioned in the vertical direction at a position laterally outside the fuel tank, so that the right or left connecting frame functions as a protective member for the fuel tank, which is advantageous in terms of preventing damage to the fuel tank. In addition to improving the support strength of the step frame and floor frame, the connecting frame also functions as a protective member for the fuel tank, so having the same member serve multiple purposes is advantageous in terms of simplifying the structure.

[0018] In the present invention, it is preferable that a plurality of protrusions protruding downward are provided on the lower part of the step, and that the step is supported by the step frame by placing the protrusions on the step frame.

[0019] According to the present invention, the protruding portion of the step is placed on the step frame, so that the step is stably supported by the step frame.

[0020] In the present invention, it is preferable that a recess extending downward is formed in the upper part of the protrusion, and that a bolt is inserted into the recess and attached across the protrusion and the step frame, thereby connecting the step to the step frame.

[0021] According to the present invention, the step is stably connected to the step frame by attaching a bolt to the contact point between the step and the step frame. The bolt fits into the recess (protrusion) of the step and rarely protrudes above the step, so it is less uncomfortable for the worker standing on the step.

[0022] In the present invention, the step has a front step and a rear step connected to the rear of the front step, and the step frame has a front step frame that supports the front step from below and a rear step frame that supports the rear step from below, and it is preferable that by not providing the rear step and rear step frame, an installation area for installing an agricultural material supply device that can supply agricultural materials to the rice field surface is formed rearward of the front step and front step frame.

[0023] In paddy field working machines, the same model may be produced in two types: one equipped with an agricultural material supplying device that can supply agricultural materials to the surface of the rice field, and another type that is not equipped with the agricultural material supplying device. According to the present invention, the step has a front step and a rear step, and the step frame has a front step frame and a rear step frame. Therefore, when producing a model that is not equipped with an agricultural material supply device, it is sufficient to provide a front step (front step frame) and a rear step (rear step frame) on the step (step frame), thereby obtaining a wide step.

[0024] When producing a model equipped with an agricultural material supply device, it is sufficient to provide a front step (front step frame) on the step (step frame) and not provide a rear step (rear step frame). This creates an installation area for the agricultural material supply device in the rear step (rear step frame) section, so the agricultural material supply device can be installed in the installation area without any difficulty.

[0025] According to the present invention, by providing or not providing a rear step (rear step frame) in the step (step frame), it becomes possible to easily produce models equipped with an agricultural material supply device and models not equipped with an agricultural material supply device, thereby improving the productivity of paddy field working machines. [Brief explanation of the drawings]

[0026] [Figure 1] FIG. 1 is a left side view of a riding rice transplanter. [Figure 2] FIG. 1 is a plan view of a riding rice transplanter. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] FIG. 10 is a plan view of the vicinity of the right and left floor frames. [Figure 6]FIG. 2 is a plan view of the vicinity of the vehicle frame, the front step frame, and the rear step frame. [Figure 7] FIG. 2 is a left side view of the vicinity of the body frame, floor frame, front step frame, and rear step frame. [Figure 8] FIG. 2 is a longitudinal sectional front view of the vicinity of the spring bearing member and the suspension spring. [Figure 9] FIG. [Figure 10] FIG. [Figure 11] FIG. 2 is a perspective view of a right step and a left step. [Figure 12] FIG. 2 is a plan view of the right step and the left step. [Figure 13] FIG. 2 is a bottom view of the right step and the left step. [Figure 14] FIG. 2 is a longitudinal sectional front view of the vicinity of the right step and the left step. [Figure 15] FIG. 2 is a longitudinal left side view of the vicinity of the right and left legs of the seat. [Figure 16] FIG. [Figure 17] FIG. [Figure 18] FIG. [Figure 19] FIG. [Figure 20] FIG. [Figure 21] FIG. [Figure 22] FIG. [Figure 23] FIG. [Figure 24] FIG. [Figure 25] FIG. 2 is a longitudinal sectional front view of the right and left side panels. [Figure 26] 10A and 10B show the openings in the right and left side panels. [Figure 27]FIG. 2 is a left side view of the vicinity of the engine and transmission case. [Figure 28] FIG. 2 is a plan view of the vicinity of the engine and transmission case. [Figure 29] FIG. 3 is a vertical sectional front view of the vicinity of a fertilizer application device in a first alternative embodiment of the invention. [Figure 30] FIG. 4 is a rear view of the vicinity of the fertilizer application device in the first alternative embodiment of the invention. [Figure 31] FIG. 3 is a left side view of the vicinity of the fertilizer application device in the first alternative embodiment of the invention. [Figure 32] FIG. 4 is a longitudinal sectional left side view of the vicinity of the fertilizer application device in a first alternative embodiment of the invention. DETAILED DESCRIPTION OF THE INVENTION

[0027] Figures 1 to 32 show a riding rice transplanter, which is an example of a paddy field working machine, and in Figures 1 to 32, F indicates the forward direction, B indicates the backward direction, U indicates the upward direction, D indicates the downward direction, R indicates the right direction, and L indicates the left direction.

[0028] (Overall configuration of riding rice transplanter) As shown in Figures 1 and 2, a machine frame 3, which is the machine body, is supported by right and left front wheels 1 for traveling and right and left rear wheels 2 for traveling. A link mechanism 4 extends rearward from the rear of the machine frame 3, and a seedling planting device 5, which is a working device, is supported at the rear of the link mechanism 4.

[0029] As shown in Figures 1 and 5, the transmission case 25 is connected to the front of the body frame 3, and a support frame 42, which is frame-shaped in a plan view, is connected to the front of the transmission case 25 and extends forward.

[0030] An engine 49 is supported by the support frame 42 and provided at the front of the vehicle frame 3, and a bonnet 58 is provided to house the engine 49. A steering handle 59 for steering the front wheels 1 is provided behind the bonnet 58.

[0031] 1 and 2, a floor 38 is provided on the machine frame 3, and a step 43 is provided at the rear of the machine frame 3 so as to be located at a position higher than the floor 38. A driver's seat 60 is located in the center of the front of the step 43, and a seat 87 is provided on the step 43.

[0032] (Configuration of seedling planting device and spare seedling tray) As shown in Figures 1 and 2, the seedling planting device 5 is configured as an eight-row planting type, and includes four planting transmission cases 6 supported at the rear of the link mechanism 4, a rotating case 7 rotatably supported on the right and left rear parts of the planting transmission cases 6, a pair of planting arms 8 supported on the rotating case 7, multiple floats 9, and a seedling tray 10.

[0033] Right and left support frames 61 are connected to the right and left parts of support frame 42 and extend upward laterally outward from the front right and left parts of floor 38, and spare seedling trays 62 are attached to the top of support frame 61. Spare seedling trays 63 are attached to the bottom of support frame 61, spare seedling tray 64 is attached to the front part of spare seedling tray 63 so as to be able to swing up and down, and spare seedling tray 65 is attached to the rear part of spare seedling tray 63 so as to be able to swing up and down.

[0034] (Aircraft frame configuration) 5, 6, and 7, the right and left body frames 3 are arranged along the fore-and-aft direction, and the body frames 3 are made of rectangular pipes with a square cross section. The right and left connecting parts 11 are connected downward to the front of the body frames 3, and the right and left frames 12 are connected between the lower parts of the connecting parts 11 and the middle parts of the body frames 3 between the fore and aft. A transmission case 25 is connected to the front of the body frames 3 and the connecting parts 11.

[0035] Right and left flat plate-shaped vertical frames 13 and right and left square pipe-shaped vertical frames 14, 15, 16 are connected to the body frame 3 and extend upward from the body frame 3. Right and left square pipe-shaped horizontal frames 17 are connected to the upper parts of the vertical frames 13, 14, 15 in the front-to-rear direction. Right and left square pipe-shaped horizontal frames 18 are connected to the upper parts of the vertical frames 15, 16 in the front-to-rear direction.

[0036] A square pipe-shaped horizontal frame 19 is connected in the left-right direction across the lower parts of the body frame 3 and the vertical frames 13. A square pipe-shaped horizontal frame 21 is connected in the left-right direction across the horizontal frames 17, and a square pipe-shaped horizontal frame 22 is connected in the left-right direction across the upper parts of the vertical frames 16. An angle-shaped horizontal frame 23 (see Figure 8) is connected in the left-right direction across the rear of the body frame 3.

[0037] An upper link 4a of the link mechanism 4 is supported by the upper part of the vertical frame 16 and extends rearward so as to be able to swing up and down about an axis P1 along the left-right direction. A lower link 4b of the link mechanism 4 is supported by the rear of the machine frame 3 and extends rearward so as to be able to swing up and down about an axis P2 along the left-right direction.

[0038] A hydraulic cylinder 24 is connected between the position of the axis P1 of the vertical frame 16 and the rear part of the lower link 4b of the link mechanism 4, and the extension and contraction of the hydraulic cylinder 24 causes the link mechanism 4 to swing up and down. With the above configuration, the link mechanism 4 (upper link 4a and lower link 4b) is supported by the rear part (vertical frame 16) of the machine body frame 3 and extends rearward.

[0039] (Front and rear wheel support configuration) As shown in Figures 1 and 5, right and left front axle cases 26 are connected to the right and left parts of the transmission case 25 and extend outward to the right and left, and the right and left front wheels 1 are supported on the front axle cases 26 in a steerable manner.

[0040] 1 and 7, a rear axle case 27 is provided that supports right and left rear wheels 2. Right and left brackets 28 are connected to the front-to-rear intermediate portion of the vehicle frame 3, and right and left upper links 29 are supported by the brackets 28 and extend rearward so as to be able to swing up and down about an axis P3 that runs along the left-right direction. Right and left lower links 30 are supported by the lower portions of the connecting portion 11 and extend rearward so as to be able to swing up and down about an axis P4 that runs along the left-to-right direction.

[0041] As shown in Figures 7 and 8, the rear of the upper link 29 is connected to the upper part of the front part of the rear axle case 27 so as to be able to swing up and down, and the rear of the lower link 30 is connected to the connecting pin 20 at the lower part of the front part of the rear axle case 27 so as to be able to swing up and down.

[0042] A bracket 31 is connected downward to the rear of the right vehicle frame 3. A lateral rod 32 is supported by the bracket 31 and extends leftward so as to be swingable up and down around an axis P5 along the front-to-rear direction, and the left portion of the lateral rod 32 is connected to the rear of the rear axle case 27 so as to be swingable up and down.

[0043] Right and left spring support members 33 are attached to the rear of the vehicle frame 3, and right and left coil suspension springs 34 are attached between the spring support members 33 and the connecting pin 20 of the rear axle case 27, and the rear axle case 27 is supported on the vehicle frame 3 via the suspension springs 34.

[0044] With the above configuration, the right and left upper links 29, the right and left lower links 30, the lateral rod 32, and the right and left suspension springs 34 form a five-link type suspension mechanism, and the rear axle case 27 is supported on the vehicle frame 3 via the suspension mechanism.

[0045] (Configuration of spring support member) As shown in Figures 8 and 9, the spring support member 33 is made of a flat plate and has a main body portion 33a that extends in the left-right direction, a right mounting portion 33b formed by bending the right front and right rear portions of the main body portion 33a upward, and a left mounting portion 33c formed by bending the left front and left rear portions of the main body portion 33a upward.

[0046] The main body 33a of the spring support member 33 is attached to the lower part 3a of the body frame 3 by welding, and extends to the right from the right side 3b of the body frame 3, and extends to the left from the left side 3c of the body frame 3.

[0047] The right mounting portion 33b of the spring receiving member 33 is attached by welding to the right side portion 3b of the body frame 3. As a result, the right mounting portion 33b of the spring receiving member 33 is attached across the portion of the main body portion 33a of the spring receiving member 33 that extends rightward from the right side portion 3b of the body frame 3 and the right side portion 3b of the body frame 3.

[0048] The left mounting portion 33c of the spring receiving member 33 is attached by welding to the left side portion 3c of the body frame 3. As a result, the left mounting portion 33c of the spring receiving member 33 is attached across the portion of the main body portion 33a of the spring receiving member 33 that extends leftward from the left side portion 3c of the body frame 3 and the left side portion 3c of the body frame 3.

[0049] There are provided right and left flat plate-shaped connecting members 35, and the cylindrical portions 35a are connected downward to the connecting members 35. Right and left rods 36 are attached to the connecting pins 20 of the rear axle case 27 and extend upward, and the rods 36 are inserted into the cylindrical portions 35a of the connecting members 35 so as to be slidable in the up and down direction.

[0050] The cylindrical portion 35a and rod 36 of the connecting member 35 are positioned inside the suspension spring 34, and the upper portion of the suspension spring 34 is abutted against the connecting member 35, which is connected to the main body portion 33a of the spring support member 33 by a bolt 37. The right and left spring bearing members 33 and the right and left connecting members 35 are symmetrical in shape and have the same structure.

[0051] (Configuration of attachment between vertical frame and spring support member) As shown in Figures 8 and 9, the lower part of the vertical frame 15 (see the above-mentioned (Configuration of the aircraft frame) and Figures 6 and 7) is cut out, and a horizontal portion 15a and an extension portion 15b extending downward from the horizontal portion 15a are formed at the lower part of the vertical frame 15, and a slit 15c is formed in the extension portion 15b.

[0052] The horizontal portion 15a of the vertical frame 15 is abutted against the upper portion 3d of the body frame 3 and attached by welding. The left mounting portion 33c of the spring receiving member 33 is inserted into the slit 15c of the vertical frame 15, and the horizontal portion of the extending portion 15b of the vertical frame 15 is abutted against the left side portion 3c of the body frame 3 and attached by welding. The lower portion of the extending portion 15b of the vertical frame 15 is abutted against the main body portion 33a of the spring receiving member 33 and attached by welding.

[0053] The lower portions of the right and left vertical frames 15 are symmetrical and have the same structure. The attachment structure between the lower portion of the right vertical frame 15 and the right spring receiving member 33 and the attachment structure between the lower portion of the left vertical frame 15 and the left spring receiving member 33 are symmetrical and have the same structure.

[0054] With the above configuration, the lower part of the vertical frame 15 is attached across the upper part 3d of the body frame 3, the side parts 3b and 3c of the body frame 3, and the part of the main body part 33a of the spring receiving member 33 extending from the side parts 3b and 3c of the body frame 3, and the lower part of the vertical frame 15 is attached across the spring receiving member 33 and the body frame 3. The vertical frame 15 is attached to the spring receiving member 33 and extends upward from the spring receiving member 33.

[0055] (Overall floor layout) 1 and 2, the floor 38 has a front floor 39, a right floor 40, and a left floor 41. Rubber floor mats (not shown) are placed across the right floor 40 and the left floor 41.

[0056] The front floor 39 is made of synthetic resin and is integrally formed, spanning both the right and left sides of the hood 58, and is configured in a symmetrical shape. An opening 39a is formed in the front floor 39 above the front wheels 1, with multiple crosspieces arranged at intervals along the lateral direction. An operator can visually observe the front wheels 1 (see FIG. 1) through the opening 39a in the front floor 39.

[0057] The right floor 40 is provided so as to be connected to the right rear part of the front floor 39, and the left floor 41 is provided so as to be connected to the left rear part of the front floor 39. The right floor 40 and the left floor 41 are integrally formed from synthetic resin and are configured in a symmetrical shape.

[0058] Openings 40a, 41a, each having a plurality of crosspieces arranged at intervals along the horizontal direction, are formed above the front wheels 1 on the right floor 40 and the left floor 41. A worker can visually check the front wheels 1 (see FIG. 1) through the openings 40a, 41a in the right floor 40 and the left floor 41.

[0059] (Configuration of the floor frame that supports the floor) As shown in Figures 5, 6 and 7, the right and left floor frames 50 are provided across the right and left body frames 3 and the support frame 42, and the right and left floor frames 50 are configured to have a symmetrical shape.

[0060] The floor frame 50 is provided with horizontal frames 51, 52 extending in the left-right direction, and three frames 53 extending in the front-rear direction are connected across the horizontal frames 51, 52, with the ends of the horizontal frames 51, 52 connected to the machine frame 3. A footrest 70 (see Figures 1 and 2) for an operator to use when getting on and off the machine is connected across the horizontal frames 51 and the outermost frame 53.

[0061] Two frames 54 extending in the front-to-rear direction are connected to the horizontal frame 52 and extend forward, and a horizontal frame 55 extending in the left-to-right direction is connected between the outermost frames 53 and 54. A frame 56 extending in the front-to-rear direction is connected to the horizontal frame 55 and extends forward, and a horizontal frame 57 extending in the left-to-right direction is connected between the front portions of the frames 54, 56, with one end of the horizontal frame 57 connected to the front portion of the support frame 42.

[0062] With the above configuration, in the floor 38, the right portion of the front floor 39 and the right floor 40 are attached to the right floor frame 50 and are supported from below by the right floor frame 50. The left portion of the front floor 39 and the left floor 41 are attached to the left floor frame 50 and are supported from below by the left floor frame 50.

[0063] (Overall structure of steps) As shown in Figures 1, 2 and 3, the step 43 has a right step 44 which is a front step, a left step 45 which is a front step, right and left rear steps 46, right and left rear steps 47, and right and left lateral steps 48.

[0064] (Right and left step configuration) As shown in Figures 11 and 12, the right step 44 and the left step 45 have upper surface portions 44a, 45a, front surface portions 44b, 45b, side surface portions 44c, 44c, and extension portions 44d, 45d, and are integrally constructed from synthetic resin, and are configured in a bilaterally symmetrical shape except for one part.

[0065] Openings 44e, 45e are formed in the upper surface portions 44a, 45a, and a plurality of crosspieces 44f, 45f are provided in the openings 44e, 45e so as to be aligned at intervals along the lateral direction. The openings 44e, 45e are located above the rear wheel 2 (see FIG. 1), and an operator can visually observe the rear wheel 2 through the openings 44e, 45e in the right step 44 and the left step 45.

[0066] Front surface portions 44b, 45b are connected to the front portions of the upper surface portions 44a, 45a and extend downward. Horizontal surface portions 44c, 45c are connected across the horizontal portions of the upper surface portions 44a, 45a and the horizontal portions of the front surface portions 44b, 45b. Extension portions 44d, 45d are connected to the lower portions of the front surface portions 44b, 45b and extend forward. Cutout portions 44g, 45g are provided across the upper surface portions 44a, 45a and the front surface portions 44b, 45b.

[0067] Wall portions 44h, 45h are formed on the sides of the upper surface portions 44a, 45a in the front-rear direction so as to be higher than the upper surface portions 44a, 45a. Wall portions 44i, 45i are formed on the rear portions of the upper surface portions 44a, 45a in the left-right direction so as to be higher than the upper surface portions 44a, 45a. In the right step 44, a protruding portion 44q that protrudes forward is provided on the side of the front surface portion 44b, and an opening 44r is formed at the top of the protruding portion 44q.

[0068] As shown in Figures 11 to 14, a plurality of downwardly protruding portions 44j, 45j, 44k, 45k are provided on the lower surface portions of the upper surface portions 44a, 45a and the lower portions of the extension portions 44d, 45d, and a large number of vertical wall-shaped ribs 44m, 45m are provided along the front-to-back, left-to-right and diagonal directions across the protruding portions 44j, 45j, 44k, 45k.

[0069] The protrusions 44j, 45j are recessed downward from the upper surface portions 44a, 45a and the extending portions 44d, 45d, and a recess extending downward is formed at the top of the protrusions 44j, 45j, so that the protrusions 44j, 45j are open upward. Small openings 44n, 45n and drainage portions 44p, 45p are formed at the bottom of the protrusions 44j, 45j.

[0070] The protrusions 44k, 45k are cylindrical and extend downward from the upper surface portions 44a, 45a and the extending portions 44d, 45d, respectively. The bottoms of the protrusions 44j, 45j and the lower ends of the protrusions 44k, 45k are set at the same height, and the lower ends of the ribs 44m, 45m are set at a higher position than the bottoms of the protrusions 44j, 45j and the lower ends of the protrusions 44k, 45k.

[0071] (Configuration of the next step in a step) As shown in FIGS. 16, 17, and 18, the right rear step 46 and the left rear step 46 are the same, and the rear steps 46 are integrally formed from synthetic resin and are configured in a symmetrical shape.

[0072] The rear step 46 is provided with a main body 46a, an opening 46b formed in the left-right center of the main body 46a, and a plurality of crosspieces 46c are provided in the opening 46b so as to be aligned at intervals along the lateral direction. The opening 46b is located above the rear wheel 2, and an operator can visually observe the rear wheel 2 (see FIG. 1) through the opening 46b of the rear step 46.

[0073] A plurality of protrusions 46d, 46e that protrude downward are provided at the bottom of the main body 46a, and a number of vertical wall-shaped ribs 46f are provided along the front-to-back and left-to-right directions across the protrusions 46d, 46e.

[0074] The protrusion 46d is recessed downward from the main body 46a, and a recess that extends downward is formed in the upper surface of the protrusion 46d, so that the protrusion 46d is open upward. A small opening 46g and a drainage section 46h are formed in the bottom of the protrusion 46d.

[0075] The protrusion 46e is formed in a cylindrical shape that extends downward from the main body 46a and is open downward. The bottom of the protrusion 46d, the lower end of the protrusion 46e, and the lower end of the rib 46f are set at the same height.

[0076] As shown in FIG. 19, the right rear step 47 and the left rear step 47 are the same, and the rear steps 47 are integrally made of synthetic resin and are configured to have a symmetrical shape. The rear step 47 is provided with a main body 47a, an opening 47b, a crosspiece 47c and a protrusion 47d that are the same as the main body 46a, the opening 46b, the crosspiece 46c and the protrusion 46d of the rear step 46, and is provided with a protrusion (not shown), a rib (not shown), an opening (not shown) and a water drainage portion (not shown) that are the same as the protrusion 46e, the rib 46f, the opening 46g and the water drainage portion 46h of the rear step 46.

[0077] In the step 47, a wall portion 47i is formed in the rear portion of the main body portion 47a along the left-right direction so as to be higher than the main body portion 47a. The rear step 47 has the same shape as the rear step 46, except for the wall portion 47i.

[0078] (Horizontal step configuration in steps) 20, 21, and 22, the horizontal step 48 has a first portion 48a and a second portion 48b that are separated from each other, and the first portion 48a and the second portion 48b are integrally formed from synthetic resin. In the right and left horizontal steps 48, the first portion 48a and the second portion 48b are the same.

[0079] The first part 48a is configured with crosspieces arranged in a grid pattern along the front-to-back and left-to-right directions, and a wall part 48c protruding downward is formed along the front-to-back direction on the side of the first part 48a.

[0080] The second part 48b is configured with crosspieces arranged in a grid pattern along the front-to-back and left-to-right directions, and wall parts 48d that protrude upward and downward are formed along the front-to-back directions on the sides of the second part 48b.

[0081] When the horizontal step 48 is used as the right horizontal step 48, the first portion 48a is set so that the wall portion 48c is positioned on the outer right side and faces downward. The second portion 48b is positioned to the right of the first portion 48a, and is set so that one wall portion 48d faces upward and the other wall portion 48d faces downward.

[0082] When the horizontal step 48 is used as the left horizontal step 48, the first part 48a is reversed (flipped front to back) relative to the right first part 48a, and the wall part 48c is positioned on the left outer side and faces downward. The second part 48b is reversed (flipped upside down) relative to the right second part 48b and placed on the left side of the first part 48a, with one wall part 48d facing downward and the other wall part 48d facing upward.

[0083] (Overall structure of the step frame that supports the step) As shown in FIGS. 6 and 7, a step frame 66 is provided to support the step 43 from below, and the step frame 66 is supported by the machine frame 3.

[0084] As shown in Figures 6 and 7, the step frame 66 has a front step frame 67 that supports the front steps, that is, the right step 44 and the left step 45, from below, and a rear step frame 68 that supports the rear steps 46, 47 from below, and as shown in Figures 1, 4, and 31, has a side step frame 69 that supports the side step 48 from below.

[0085] (Configuration of the front step frame that supports the right and left steps) 6 and 7, horizontal frames 71 and 72 extending in the left-right direction are provided on the front step frame 67, and a mounting bracket 71a is attached to the horizontal frame 71. A frame 73 extending in the front-rear direction is connected across the horizontal frames 71 and 72.

[0086] A frame 74 extending along the front-rear direction is connected across the lateral ends of the horizontal frames 71, 72 and extends forward from the horizontal frame 72. A frame 75 extending along the front-rear direction is connected to the horizontal frame 72 and extends forward. A horizontal frame 76 extending along the left-right direction is connected across the front ends of the frames 74, 75. A support frame 77 extending along the front-rear direction is connected to the horizontal frame 71 and extends rearward.

[0087] In the front step frame 67 configured as above, the horizontal frame 71 is connected to the upper parts of the right and left vertical frames 15 (see the above-mentioned (Configuration of the machine body frame)) and the right and left horizontal frames 17. The horizontal frame 72 is connected to the upper parts of the right and left vertical frames 14 and the right and left horizontal frames 17. As a result, the step frame 66 (front step frame 67) is attached to the upper part of the vertical frame 15 and is attached to the upper part of the vertical frame 14.

[0088] (Relationship between floor frame and step frame) 6 and 7, right and left floor frames 50 are provided at the front of the vehicle frame 3. A front step frame 67 (step frame 66) is provided at the rear of the vehicle frame 3 so as to be positioned higher than the floor frames 50.

[0089] Multiple right connecting frames 79 are attached in the vertical direction across the right front portion (right horizontal frame 76) of the step frame 66 (front step frame 67) and the right rear portion (horizontal frame 51 of the right floor frame 50) of the floor frame 50.

[0090] Multiple left connecting frames 79 are attached in the vertical direction across the left front portion (left horizontal frame 76) of the step frame 66 (front step frame 67) and the left rear portion (horizontal frame 51 of the left floor frame 50) of the floor frame 50.

[0091] As shown in Figure 10, a fuel tank 80 is provided. The front lower portion of the fuel tank 80 is attached to the horizontal frame 51 of the right floor frame 50, and the rear upper portion of the fuel tank 80 is attached to the right portion of the horizontal frame 72 of the front step frame 67. As a result, the fuel tank 80 is provided below the right front portion of the step frame 66 (front step frame 67). The right outermost connecting frame 79 is disposed at a position on the right lateral outer side of the fuel tank 80 along the vertical direction.

[0092] (Support structure of right and left steps on front step frame) As described above (Configuration of the right and left steps in the steps) and shown in FIGS. 11 to 14, the right step 44 and the left step 45 are provided with protrusions 44j, 45j, 44k, 45k, ribs 44m, 45m, and crosspieces 44f, 45f.

[0093] 6 and 14, when the right step 44 and the left step 45 are placed on the front step frame 67, the protrusions 44j, 45j, 44k, 45k of the right step 44 and the left step 45 are placed on the frames 73, 75 and the support frame 77 of the front step frame 67. The ribs 44m, 45m and the crosspieces 44f, 45f of the right step 44 and the left step 45 are placed on the horizontal frames 71, 72 of the front step frame 67. As a result, the right step 44 and the left step 45 are supported from below by the front step frame 67 (step frame 66).

[0094] As shown in Figure 14, at the protrusions 44j, 45j of the right step 44 and the left step 45, the bolts 81 enter the protrusions 44j, 45j of the right step 44 and the left step 45 and are attached across the protrusions 44j, 45j of the right step 44 and the left step 45 and the frames 73, 75 and the receiving frame 77 of the front step frame 67. As a result, the right step 44 and the left step 45 are connected to the front step frame 67 (step frame 66).

[0095] (Configuration of rear step frame supporting rear step) 6 and 7, the rear step frame 68 is provided with a horizontal frame 82 extending in the left-right direction, and a plurality of support frames 83 extending in the front-rear direction are connected to the horizontal frame 82 and extend forward and rearward. A mounting bracket 84 is attached to the horizontal frame 82, and a mounting frame 85 is connected to the horizontal frame 82 and extends forward.

[0096] In the front step frame 67 and the rear step frame 68, the mounting bracket 84 of the rear step frame 68 is bolted to the rear of the lateral frame 18 (see (Configuration of the machine body frame) above). The mounting frame 85 of the rear step frame 68 is bolted to the mounting bracket 71a of the lateral frame 71 of the front step frame 67 (see (Configuration of the front step frame supporting the right and left steps) above).

[0097] As a result, the rear step frame 68 is attached to the front step frame 67, and the rear step frame 68 is attached to the top of the vertical frame 15 (see the above-mentioned (Configuration of the aircraft frame)) via the front step frame 67, and is attached to the top of the vertical frame 14.

[0098] (Support structure of rear step in rear step frame) As described above (Configuration of rear steps in steps) and as shown in FIGS. 16 to 19, the rear steps 46, 47 are provided with protrusions 46d, 47d, 46e, a rib 46f, and crosspieces 46c, 47c.

[0099] When the rear steps 46, 47 are placed on the rear step frame 68, the protrusions 46d, 47d, 46e, rib 46f, and crosspieces 46c, 47c of the rear steps 46, 47 are placed on the support frame 83 of the rear step frame 68. As a result, the rear steps 46, 47 are supported from below by the rear step frame 68 (step frame 66).

[0100] Similar to the right step 44 and left step 45 described above (support configuration of the right and left steps on the front step frame) and shown in Figure 14, in the rear steps 46, 47, bolts 81 are inserted into the protrusions 46d, 47d of the rear steps 46, 47 and are attached across the protrusions 46d, 47d of the rear steps 46, 47 and the support frame 83 of the rear step frame 68. As a result, the rear steps 46, 47 are connected to the rear step frame 68 (step frame 66).

[0101] (Configuration of the horizontal step frame that supports the horizontal step) As shown in Figures 1, 2, 3, 4 and 31, right and left handrail frames 86 are provided, which are formed by bending a pipe material.

[0102] The front lower part 86a of the handrail frame 86 is connected to the horizontal frame 51 of the floor frame 50 (see the above (Configuration of the floor frame that supports the floor) and Figure 5). The rear lower part 86b of the handrail frame 86 is connected to the horizontal frame 71 of the front step frame 67 (see the above (Configuration of the front step frame that supports the right and left steps) and Figure 6).

[0103] The right and left horizontal step frames 69 are arranged along the front-to-rear direction and connected to the rear lower portion 86b of the handrail frame 86. The horizontal step 48 (first portion 48a and second portion 48b) is connected to the horizontal step frames 69 with bolts.

[0104] As a result, the right handrail frame 86 and side step frame 69 and the left handrail frame 86 and side step frame 69 are configured to be symmetrical. The right and left handrail frames 86 are positioned laterally outward from the right part of the right step 44 and laterally outward from the left part of the left step 45, and extend upward.

[0105] (Arrangement of right and left steps, rear steps, and side steps) As shown in Figures 3, 11, and 12, the right step 44 and the left step 45 are arranged side by side in the left-right direction so as to be in contact with each other, and are arranged so as to connect to the rear of the right floor 40 and the left floor 41 (see the above-mentioned (Overall floor structure) and Figure 2).

[0106] The upper surface 44a of the right step 44 and the upper surface 45a of the left step 45 are disposed at the same height. The upper end of the wall 44i of the right step 44 and the upper ends of the wall portions 45h, 45i of the left step 45 are disposed at the same height.

[0107] The right step 44 covers the fuel tank 80, with the right front part of the fuel tank 80 fitting into the protruding portion 44q of the right step 44, and the fuel filler opening 80a of the fuel tank 80 fitting into the opening 44r of the right step 44 and protruding upward.

[0108] The driver's seat 60 is disposed in the notches 44g, 45g of the right step 44 and the left step 45, and is disposed in the center of the left and right front parts of the steps 43 (the right step 44 and the left step 45).

[0109] 3, the right and left rear steps 46 are arranged side by side in the left-right direction so as to be in contact with each other, and are provided so as to be connected to the rear part (wall portion 44i) of the right step 44 and the rear part (wall portion 45i) of the left step 45. The right and left rear steps 47 are arranged side by side in the left-right direction so as to be in contact with each other, and are provided so as to be connected to the rear part of the rear step 46.

[0110] The upper surfaces of the rear steps 46 and 47 (main body portions 46a and 47a) are arranged at the same height as the upper ends of the wall portions 44h, 45h, 44i and 45i of the right step 44 and the left step 45.

[0111] As shown in Figures 3 and 4, the right lateral step 48 is provided so as to be connected to the lateral portion (wall portion 44h) of the right step 44 and the lateral portions (wall portion 45h) of the right rear steps 46, 47, and the left lateral step 48 is provided so as to be connected to the lateral portion of the left step 45 and the lateral portions of the left rear steps 46, 47.

[0112] The upper surface of the horizontal step 48 is located at the same height as the upper surfaces of the rear steps 46, 47 (main bodies 46a, 47a) and the upper ends of the wall portions 44h, 45h, 44i, 45i of the right step 44 and the left step 45. The upper end of the wall portion 48d of the horizontal step 48 and the upper end of the wall portion 47i of the rear step 47 are located at the same height.

[0113] (Seating configuration) As shown in Figures 3, 4, 14 and 15, a seat portion 87 is provided. The seat portion 87 is formed by bending a pipe material, and has a rod-shaped horizontal portion 87a that extends in the left-right direction, a rod-shaped right leg portion 87b that extends downward from the right portion of the horizontal portion 87a, a rod-shaped left leg portion 87c that extends downward from the left portion of the horizontal portion 87a, an angle-shaped mounting bracket 87d that is connected to the lower ends of the right leg portion 87b and the left leg portion 87c, and a boss portion 87e that is connected to the mounting bracket 87d.

[0114] As shown in Figures 4 and 14, the right leg 87b of the seat 87 is bent so that the lower part of the right leg 87b of the seat 87 is positioned closer to the center of the step 43 than the right part of the horizontal part 87a of the seat 87.

[0115] The left leg 87c of the seat 87 is bent so that the lower part of the left leg 87c of the seat 87 is positioned closer to the center of the step 43 than the left part of the horizontal part 87a of the seat 87. As a result, the width W1 of the horizontal part 87a of the seat 87 is greater than the width W2 of the lower parts of the right leg 87b and left leg 87c of the seat 87.

[0116] (Support structure of the seat) As shown in Figures 3, 14, and 15, right and left mounting brackets 71b are attached to the horizontal frame 71 of the front step frame 67 (see the above (Configuration of the front step frame supporting the right and left steps) and Figure 6), and the mounting brackets 71b are located below the openings 44e, 45e of the right step 44 and left step 45.

[0117] The right mounting bracket 87d (lower part of the right leg 87b) of the seat 87 is placed on the crosspiece 44f of the right step 44, and the right boss 87e of the seat 87 is inserted into the opening 44e of the right step 44 and placed on the right mounting bracket 71b of the horizontal frame 71 (front step frame 67).

[0118] The left mounting bracket 87d (lower part of the left leg 87c) of the seat 87 is placed on the crosspiece 45f of the left step 45, and the left boss 87e of the seat 87 is inserted into the opening 45e of the left step 45 and placed on the left mounting bracket 71b of the horizontal frame 71 (front step frame 67).

[0119] A bolt 88 is inserted into a boss portion 87e of the seat portion 87, and the seat portion 87 is attached to the mounting bracket 71b of the horizontal frame 71 (front step frame 67). As a result, the bolt 88 is arranged in the vertical direction between adjacent crosspieces 44f, 45f in the openings 44e, 45e of the right step 44 and the left step 45, and is attached between the mounting bracket 87d of the seat portion 87 (the lower part of the right leg portion 87b and the left leg portion 87c) and the mounting bracket 71b of the horizontal frame 71 (front step frame 67).

[0120] When the bolt 88 is tightened, the crosspieces 44f, 45f of the right step 44 and the left step 45 are sandwiched between the mounting bracket 87d of the seat 87 and the mounting bracket 71b of the horizontal frame 71 (front step frame 67), and the right leg 87b and left leg 87c of the seat 87 are attached to the step 43 (right step 44 and left step 45).

[0121] (Seating arrangement) As shown in Figures 1 to 4, in side view and plan view, the seat portion 87 is provided along the left-right direction on the step 43 (right step 44 and left step 45) so as to be located behind the driver's seat 60, between the driver's seat 60 and the rear end of the step 43 (rear step 47).

[0122] When viewed from above and from behind, the right end of the seat portion 87 (horizontal portion 87a) is located closer to the center of the left and right of the step 43 than the right end of the step 43 (right horizontal step 48), and is located closer to the center of the left and right of the step 43 than the right end of the right step 44 (wall portion 44h).

[0123] When viewed from above and from behind, the left end of the seat portion 87 (horizontal portion 87a) is located closer to the center of the left and right sides of the step 43 than the left end of the step 43 (left horizontal step 48), and is located closer to the center of the left and right sides of the step 43 than the left end of the left step 45 (wall portion 45h).

[0124] In rear view, the lower part (mounting bracket 87d) of the right leg 87b of the seat 87 is attached to the step 43 (right step 44) closer to the center of the step 43 than the right part of the lateral part 87a of the seat 87.

[0125] In rear view, the lower part (mounting bracket 87d) of the left leg 87c of the seat 87 is attached to the step 43 (left step 45) closer to the center of the step 43 than the left part of the lateral part 87a of the seat 87.

[0126] In a rear view, the width W1 of the side portion 87a of the seat 87 and the width W2 of the lower portions of the right leg portion 87b and left leg portion 87c of the seat 87 are larger than the width W3 of the driver's seat. The right portion and right leg portion 87b of the side portion 87a of the seat 87 are located laterally outward to the right of the driver's seat 60, and the left portion and left leg portion 87c of the side portion 87a of the seat 87 are located laterally outward to the left of the driver's seat 60.

[0127] (Configuration of the upper and lower frames provided around the step) As shown in Figures 1 to 4, a lower frame 89 is attached across the lower rear parts of the right and left handrail frames 86. The lower frame 89 is formed by bending a pipe member, and has a horizontal part 89a, a right part 89b and a left part 89c, and mounting brackets 89d which are height adjustment parts connected to the ends of the right part 89b and the left part 89c.

[0128] The horizontal portion 89a of the lower frame 89 is provided along the left-right direction near the top of the rear portion of the step 43 (wall portion 47i of the rear step 47). The right portion 89b and left portion 89c of the lower frame 89 are provided along the front-to-rear direction near the top of the right and left horizontal portions (horizontal step 48) of the step 43. The mounting brackets 89d of the lower frame 89 are attached to the lower rear portions of the right and left handrail frames 86 with bolts.

[0129] An upper frame 90 is attached across the upper rear parts of the right and left handrail frames 86. The upper frame 90 is made by bending a pipe member and has a horizontal portion 90a, a right portion 90b and a left portion 90c, and mounting brackets 90d which are height-adjusting portions connected to the ends of the right portion 90b and the left portion 90c.

[0130] The horizontal portion 90a of the upper frame 90 is provided at a position spaced a predetermined distance above the horizontal portion 89a of the lower frame 89, and extends in the left-right direction along the horizontal portion 89a of the lower frame 89.

[0131] The right portion 90b and the left portion 90c of the upper frame 90 are arranged in the front-to-rear direction along the right portion 89b and the left portion 89c of the lower frame 89, at a position spaced a predetermined distance above the right portion 89b and the left portion 89c of the lower frame 89.

[0132] The mounting brackets 90d of the upper frame 90 are attached with bolts to the upper rear portions of the right and left handrail frames 86. A plurality of frames 91 are connected across the upper frame 90 and the lower frame 89.

[0133] In side and plan views, the upper rear portion (lateral portion 90a) of the step 43 on the upper frame 90 is located rearward of the upper rear portion (lateral portion 89a) of the step 43 on the lower frame 89.

[0134] The right and left handrail frames 86 are provided at the right and left ends of the step 43 (right and left horizontal steps 48) in front of the upper frame 90 and lower frame 89. The upper frame 90 is provided at a position lower than the upper ends of the handrail frames 86.

[0135] A plurality of openings (not shown) for attaching bolts are opened in the vertical direction in the handrail frame 86. By changing the attachment positions of the attachment brackets 90d, 89d of the upper frame 90 and the lower frame 89 up or down using the openings in the handrail frame 86, the attachment position of the handrail frame 86 on the upper frame 90 and the lower frame 89 can be changed up or down.

[0136] (Hood configuration) 23 and 24, right and left lights 92, a lattice-shaped front grille 93, and a center mascot 94 (see FIGS. 1 and 2) are provided in the front part of the hood 58. A right side panel 95 is provided on the right side surface of the hood 58, and a left side panel 96 is provided on the left side surface of the hood 58.

[0137] The right and left side panels 95, 96 have frame portions 95a, 96a that form the outer periphery, and frame portions 95b, 96b that are connected in the front-to-rear direction across the front and rear of the frame portions 95a, 96a, and lattice-shaped frame portions 95c, 96c are provided between the frame portions 95a, 96a and the frame portions 95b, 96b.

[0138] A right opening 95d having an elongated hexagonal shape is formed along the front-to-rear direction between the frame portions 95c of the right side panel 95. A plurality of left openings 96d having an elongated hexagonal shape are formed along the front-to-rear direction between the frame portions 96c of the left side panel 96.

[0139] (Right and left side panel opening configuration) As shown in Figures 25 and 26, the frame portion 95c (opening 95d) of the right side panel 95 has a predetermined left-right width along the left-right direction, and the cross-sectional shape of the frame portion 95c of the right side panel 95 is rectangular.

[0140] The outer edge 95e and inner edge 95f of the opening 95d of the right side panel 95 have the same elongated hexagonal shape, and the area of ​​the elongated hexagonal shape of the edges 95e, 95f of the right side panel 95 is the cross-sectional area for air to pass through the opening 95d of the right side panel 95.

[0141] The frame portion 96c (opening 96d) of the left side panel 96 has a predetermined width in the left-right direction, and the cross section of the frame portion 96c of the left side panel 96 is V-shaped.

[0142] A front-to-back width WL11 of the outer edge 96e of the left side panel 96 is larger than a front-to-back width WL12 of the inner edge 96f of the left side panel 96. A vertical width WL21 of the outer edge 96e of the left side panel 96 is larger than a vertical width WL22 of the inner edge 96f of the left side panel 96.

[0143] The opening 96d of the left side panel 96 is formed to expand outward in cross section so that the front-to-rear width WL11 and the up-to-down width WL21 of the portion of the opening 96d of the left side panel 96 on the outside of the bonnet 58 are larger than the front-to-rear width WL12 and the up-to-down width WL22 of the portion of the opening 96d of the left side panel 96 on the inside of the bonnet 58.

[0144] As a result, the elongated hexagonal shape of the outer edge 96e of the opening 96d of the left side panel 96 is larger than the elongated hexagonal shape of the inner edge 96f of the opening 96d of the left side panel 96.

[0145] As a result, at the opening 96d of the left side panel 96, the cross-sectional area of ​​air passing through the part of the opening 96d of the left side panel 96 on the inside side of the bonnet 58 is set to be different from the cross-sectional area of ​​air passing through the part of the opening 96d of the left side panel 96 on the outside side of the bonnet 58.

[0146] 25 and 26, at the openings 95d, 96d of the right and left side panels 95, 96, the front-to-back width WR1 of the edge portions 95e, 95f of the right side panel 95 is the same as the front-to-back width WL11 of the outer edge portion 96e of the left side panel 96. The vertical width WR2 of the edge portions 95e, 95f of the right side panel 95 is the same as the vertical width WL21 of the outer edge portion 96e of the left side panel 96.

[0147] The front-to-back width WR1 of the edge portions 95e, 95f of the right side panel 95 is larger than the front-to-back width WL12 of the inner edge portion 96f of the left side panel 96. The top-to-bottom width WR2 of the edge portions 95e, 95f of the right side panel 95 is larger than the top-to-bottom width WL22 of the inner edge portion 96f of the left side panel 96.

[0148] The area of ​​the elongated hexagonal shape of the edge portions 95e, 95f of the right side panel 95 (the cross-sectional area of ​​air passing through the opening 95d of the right side panel 95) is the same as the area of ​​the elongated hexagonal shape of the outer edge portion 96e of the left side panel 96 (the cross-sectional area of ​​air passing through the portion of the opening 96d of the left side panel 96 on the outside side of the bonnet 58).

[0149] The area of ​​the elongated hexagonal shape of the edge portions 95e, 95f of the right side panel 95 (the cross-sectional area of ​​air passing through the opening 95d of the right side panel 95) is larger than the area of ​​the elongated hexagonal shape of the inner edge portion 96f of the left side panel 96 (the cross-sectional area of ​​air passing through the portion of the opening 96d of the left side panel 96 on the inside side of the bonnet 58). As a result, the cross-sectional area of ​​air passing through the opening 95d of the right side panel 95 is set to be larger than the smaller cross-sectional area of ​​air passing through the opening 96d of the left side panel 96.

[0150] In this case, the opening 96d in the left side panel 96 becomes one of the right opening 95d and the left opening 96d, and the opening 95d in the right side panel 95 becomes the other of the right opening 95d and the left opening 96d.

[0151] (Configuration near the left side of the engine) As shown in Figures 27 and 28, the engine 49 is supported laterally on the support frame 42 (see the above-mentioned (Overall configuration of the riding rice transplanter) and Figure 5) inside the hood 58. The output shaft 49a of the engine 49 protrudes leftward from the left part of the engine 49, and the output pulley 78 and the flywheel 97 are attached to the output shaft 49a of the engine 49.

[0152] As a result, in a plan view, the output shaft 49a, output pulley 78, and flywheel 97 of the engine 49 face the left side panel 96 of the hood 58 and are provided in a portion of the engine 49 facing one opening 96d.

[0153] A hydrostatic continuously variable transmission 98 is connected to the left side surface of the transmission case 25, and a transmission belt 99 is attached between the output pulley 78 and an input pulley 98a of the continuously variable transmission 98.

[0154] A support stay 103 connected to the left front portion of the engine 49 extends leftward and enters below the right floor frame 50 (see the above-mentioned (Configuration of the floor frame that supports the floor) and Figure 5). A support stay 104 connected to the left rear portion of the engine 49 extends leftward and enters below the right floor frame 50 while straddling above the transmission belt 99.

[0155] A muffler 105 is disposed in the front-to-rear direction below the right floor frame 50, with the front portion of the muffler 105 supported by a support stay 103 and the rear portion of the muffler 105 supported by a support stay 104. An exhaust pipe 106 extending from the front portion of the engine 49 is connected to the front portion of the muffler 105.

[0156] The power of the engine 49 is transmitted to the continuously variable transmission 98 via the output shaft 49a of the engine 49, the output pulley 78 and the transmission belt 99, and the power of the continuously variable transmission 98 is transmitted to a sub-transmission (not shown) inside the transmission case 25.

[0157] The power of the auxiliary transmission device is transmitted to the front wheels 1 via a transmission system (not shown) inside the front axle case 26 (see the above-mentioned (Configuration of supporting the front and rear wheels) and FIG. 5), and is transmitted to the rear wheels 2 via a transmission shaft (not shown) from the transmission case 25 to the rear axle case 27 (see the above-mentioned (Configuration of supporting the front and rear wheels) and FIG. 7), and via another transmission system (not shown) inside the rear axle case 27. The power branched off between the continuously variable transmission 98 and the sub-transmission is transmitted from the transmission case 25 to the seedling planting device 5 (see the above-mentioned (Configuration of the seedling planting device and spare seedling tray) and Figures 1 and 2) via a transmission shaft (not shown).

[0158] (Configuration near the right side of the engine) As shown in Figure 28, inside the hood 58, a fan 100 that is driven to rotate by the power of the engine 49 is provided on the right side of the engine 49. A radiator 101 is arranged along the front-to-rear direction and supported on the right side of the support frame 42 (see the above-mentioned (Overall configuration of the riding rice transplanter) and Figure 5), and a mesh member 102 that is a dustproof member is attached to the right side of the radiator 101.

[0159] As a result, the fan 100 and the radiator 101 are provided inside the hood 58 between the right side panel 95 of the hood 58 (the other opening 95d of the hood 58) and the engine 49 in a plan view. In plan view, the fan 100 is provided between the radiator 101 and the engine 49, and the mesh member 102 is provided on the radiator 101 at a portion facing the other opening 95d of the hood 58.

[0160] As the fan 100 is driven to rotate, an air flow is generated inside the hood 58 in the left-right direction from right to left, and air outside the hood 58 is introduced into the inside of the hood 58 through the opening 95d in the right side panel 95 of the hood 58 (see the above-mentioned (Configuration of the openings in the right and left side panels) and Figures 23 and 25) to cool the engine 49. In this case, the opening 95d in the right side panel 95 becomes one of the right opening 95d and the left opening 96d, and the opening 96d in the left side panel 96 becomes the other of the right opening 95d and the left opening 96d.

[0161] Air introduced into the inside of the hood 58 through the opening 95d in the right side panel 95 of the hood 58 passes through the mesh member 102, the radiator 101, and the fan 100, flows around the engine 49, and exits to the outside of the hood 58 through the opening 96d in the left side panel 96 of the hood 58 (see the above-mentioned (Configuration of the openings in the right and left side panels) and Figures 24 and 25).

[0162] (First Alternative Embodiment of the Invention) 1 to 28 show a riding rice transplanter that is not equipped with a fertilizer applicator 107. The following describes how to obtain a riding rice transplanter that is equipped with a fertilizer applicator 107, which is an agricultural material supply device, from among the riding rice transplanters shown in FIGS. 1 to 28.

[0163] (Installation area for installing a fertilizer application device in the first alternative embodiment of the invention) 3, 4 and 6, the seat portion 87, the rear steps 46 and 47 and the rear step frame 68 are removed. The wall portions 44i and 45i of the right step 44 and the left step 45 shown in Figures 11 and 12 are cut away, and the right step 44 and the left step 45 are used.

[0164] In Figures 3 and 6, since the rear steps 46, 47 and the rear step frame 68 are not provided, the area where the rear steps 46, 47 and the rear step frame 68 were provided becomes the installation area for installing the fertilizer application device 107, and the installation area for installing the fertilizer application device 107 is formed rearward of the right step 44, left step 45 and front step frame 67, and is formed between the rear parts of the right and left lateral steps 48.

[0165] (Configuration of the Fertilizer Applicator in the First Alternative Embodiment of the Invention) As shown in FIGS. 29 to 32, the fertilizer applicator 107 has a hopper 108, a plurality of delivery units 109, an air blower unit 110, a transport air duct 111, a discharge duct 112, and the like.

[0166] As shown in Figure 30, a support frame 114 is provided along the left-right direction, and right and left support frames 113 are connected to the support frame 114 and extend downward. The lower part of the support frame 113 is connected with bolts to the rear of the horizontal frame 18 (see the above-mentioned (Configuration of the aircraft frame) and Figure 6).

[0167] 29, 30, and 31, the right and left support frames 115 are connected to the lower rear parts of the handrail frame 86, and the support frame 116 along the left-right direction is connected across the right and left support frames 115. The extension part 109 is connected to the support frames 114, 116 so as to be sandwiched between the support frames 114, 116 from the front and back.

[0168] A hopper 108 for storing fertilizer, an agricultural material, is attached to the top of multiple delivery units 109, which are connected to the bottom of the hopper 108. A furrow former (not shown) is attached to the float 9 (see the above-mentioned (Configuration of the seedling planting device and spare seedling tray) and Figures 1 and 2), and a hose (not shown) is connected between the delivery units 109 and the furrow former.

[0169] Blower unit 110 is attached to the left side of support frame 114. Blower unit 110 has a blower case 110a attached to the left side of support frame 114, blower blades (not shown) housed in blower case 110a so as to be rotatable around an axis extending in the vertical direction, and an electric motor 110b that drives and rotates the blower blades.

[0170] 29, 30, and 32, a cylindrical transport air duct 111 is arranged along the left-right direction and is connected along the left-right direction across the front portions of the lower parts of the plurality of feed units 109. An air blowing switching unit 119 is connected to the left portion of the transport air duct 111, and an air blowing case 110a of the air blowing unit 110 is connected to the air blowing switching unit 119.

[0171] A cylindrical exhaust duct 112 is arranged in the left-right direction in front of the transport air duct 111 at the same height as the transport air duct 111, and is connected to the front parts of the plurality of payout units 109 in the left-right direction, with the left part of the exhaust duct 112 connected to the air blow switching unit 119. A cover 120 that protects the transport air duct 111 and the exhaust duct 112 is provided above the exhaust duct 112 in the left-right direction over substantially the entire length of the exhaust duct 112.

[0172] (Configuration of intake duct in first alternative embodiment of the invention) As shown in FIGS. 29, 39, and 31, the intake duct 117 extends downward from the lower part of the blower case 110a of the blower section 110, and extends forward below the upper surface 45a of the left step 45 toward the engine 49.

[0173] A support stay 118 is attached to the frame 73 of the front step frame 67 (see the above (Configuration of the front step frame supporting the right and left steps) and Figure 6). An intake duct 117 is supported by the support stay 118 and is positioned below the lower part 86b of the left handrail frame 86.

[0174] (Operating state of the fertilizer application device in the first alternative embodiment of the invention) As shown in Figures 29 to 32, when the blower blades in the blower section 110 are rotated by the electric motor 110b, relatively high-temperature air near the engine 49 is drawn into the intake duct 117 and guided to the blower section 110 via the intake duct 117.

[0175] The air guided to the blower section 110 causes the blower section 110 to generate a conveying wind, which is supplied from the blower switching section 119 to the conveying wind duct 111, and the conveying wind is supplied from the conveying wind duct 111 to the feed section 109.

[0176] The fertilizer discharge port (not shown) from the delivery unit 109 to the discharge duct 112 is closed, and the air blowing switching unit 119 is set to a state in which the transport air from the air blowing unit 110 is supplied to the transport air duct 111.

[0177] In the above-mentioned state, the fertilizer in the hopper 108 is discharged into the inside of the discharge unit 109 by the discharge unit 109, and the fertilizer inside the discharge unit 109 is supplied to the furrow former (see the above-mentioned (Configuration of the fertilizer application device in the first alternative embodiment of the invention)) through the hose by the conveying air supplied to the discharge unit 109 from the conveying air duct 111. As the riding rice transplanter moves forward, furrows are formed on the surface of the rice field by the furrow former, and the fertilizer supplied to the furrow former is supplied to the furrows on the surface of the rice field.

[0178] When work is completed and the fertilizer remaining in the hopper 108 is to be collected, the fertilizer discharge outlet (not shown) from the delivery section 109 to the discharge duct 112 is opened and the air blowing switching section 119 is set to a state in which the conveying air from the air blowing section 110 is supplied to the discharge duct 112. In the above-mentioned state, the fertilizer remaining in the hopper 108 is supplied to the discharge duct 112, and is transported to the outlet on the right side of the discharge duct 112 by the conveying air supplied to the discharge duct 112, and the fertilizer coming out from the outlet of the discharge duct 112 is collected in a collection bag (not shown).

[0179] (Arrangement of the fertilizer application device in the first alternative embodiment of the invention) As shown in Figures 29 to 32, the fertilizer application device 107 (hopper 108, delivery section 109, air blowing section 110, conveying air duct 111, discharge duct 112 and air blowing switching section 119) is arranged in an installation area for installing the fertilizer application device 107 (see the above-mentioned (installation area for installing the fertilizer application device in the first alternative embodiment of the invention)). The fertilizer application device 107 is disposed along the left-right direction on the rear side of the rear parts of the steps 43 (the right step 44 and the left step 45) in plan view and side view.

[0180] The fertilizer application device 107 is disposed between the rear part of the right lateral step 48 and the rear part of the left lateral step 48 in plan view and rear view. The rear part of a right lateral step 48, which is the right part of the step 43, extends rearward so as to be positioned laterally outward relative to the right part of the fertilizer application device 107. The rear part of the left lateral step 48, which is the left part of the step 43, extends rearward so as to be positioned laterally outward relative to the left part of the fertilizer application device 107.

[0181] The upper surfaces 44a, 45a of the right step 44 and the left step 45, the exhaust duct 112, the carrying airflow duct 111, the air blower case 110a of the air blower 110, and the air blower switching unit 119 are arranged at the same height.

[0182] In a front view, the upper surface portions 44a, 45a of the right step 44 and the left step 45, the exhaust duct 112, and the transport air duct 111 overlap over the entire length of the transport air duct 111 and the entire length of the exhaust duct 112. In a front view, the upper surface portion 45a of the left step 45 overlaps with the air blower case 110a of the air blower 110 and the air blowing switching unit 119.

[0183] As a result, the fertilizer applicator 107 is installed at a relatively low position in the riding rice transplanter. When the fertilizer applicator 107 is in operation (when the front and rear wheels 1 and 2 are in contact with the tillage pan and the float 9 of the seedling planting device 5 is in contact with the rice field surface), if an imaginary line (not shown) is imagined extending diagonally upward and forward from the seedling tray 10 along the seedling tray 10 in a side view, the upper end of the fertilizer applicator 107 (hopper 108) is located below the imaginary line.

[0184] Instead of the fertilizer application device 107, a chemical supply device may be provided as the agricultural material supply device, which has a hopper (not shown) for storing the agricultural material, chemicals, a plurality of delivery sections (not shown), a blower section (not shown), a transport air duct (not shown), an exhaust duct (not shown), etc., and is configured to supply chemicals to the rice field surface.

[0185] (Second Alternative Embodiment of the Invention) In the fertilizer application device 107, the air blowing section 110 and the air blowing switching section 119 may be configured to be connected to the right parts of the conveying air duct 111 and the exhaust duct 112, and the intake duct 117 may be configured to extend downward from the lower part of the air blowing case 110a of the air blowing section 110 and extend forward toward the engine 49 from the lower side relative to the upper surface part 44a of the right step 44. The intake duct 117 may be configured to be disposed above the lower portion 86b of the right (left) handrail frame 86.

[0186] (Third Alternative Embodiment of the Invention) Instead of the five-link type suspension mechanism, a three-link type suspension mechanism having right and left links and lateral rods may be employed.

[0187] (Fourth Alternative Embodiment of the Invention) The fuel tank 80 may be configured so that the front lower portion of the fuel tank 80 is attached to the horizontal frame 51 of the left floor frame 50 and the rear upper portion of the fuel tank 80 is attached to the left portion of the horizontal frame 72 of the front step frame 67, and the fuel tank 80 is provided below the left front portion of the step frame 66 (front step frame 67). In this configuration, the left outermost connecting frame 79 may be configured to be disposed at a position on the left lateral outer side relative to the fuel tank 80 along the vertical direction.

[0188] (Fifth Alternative Embodiment of the Invention) Instead of constructing the right step 44 and the left step 45 separately, the right step 44 and the left step 45 may be integrally constructed as a single front step. Instead of constructing the right and left floor frames 50 separately, the right and left floor frames 50 may be connected to each other to form a single floor frame 50.

[0189] (Sixth Alternative Embodiment of the Invention) In addition to the openings 44e, 45e of the right step 44 and the left step 45, openings dedicated to attaching the seat portion 87 may be provided in the right step 44 and the left step 45. With this configuration, the boss portion 87e of the seat portion 87 is unnecessary, so that the right step 44 and the left step 45 are sandwiched between the mounting bracket 87d of the seat portion 87 and the mounting bracket 71b of the horizontal frame 71, and the bolt 88 can be tightened through the openings of the right step 44 and the left step 45 across the mounting bracket 87d of the seat portion 87 and the mounting bracket 71b of the horizontal frame 71.

[0190] (Seventh Alternative Embodiment of the Invention) In the left side panel 96, the elongated hexagonal shape of the inner edge 96f of the opening 96d of the left side panel 96 may be configured to be larger than the elongated hexagonal shape of the outer edge 96e of the opening 96d of the left side panel 96.

[0191] As a result, at the opening 96d of the left side panel 96, the cross-sectional area of ​​air passing through the part of the opening 96d of the left side panel 96 on the inside side of the bonnet 58 is set to be different from the cross-sectional area of ​​air passing through the part of the opening 96d of the left side panel 96 on the outside side of the bonnet 58.

[0192] (Eighth Alternative Embodiment of the Invention) The engine 49 may be arranged in reverse left and right, with the output shaft 49a of the engine 49 provided on the right side of the engine 49 and the fan 100, radiator 101 and mesh member 102 arranged on the left side of the engine 49. According to this configuration, in the hood 58, the opening 95d of the right side panel 95 may be configured as shown in the right part of Fig. 5 and the lower part of Fig. 6, or may be configured as described above (seventh alternative embodiment of the invention). The opening 96d of the left side panel 96 may be configured as shown in the left part of Fig. 5 and the upper part of Fig. 6.

[0193] (Ninth Alternative Embodiment of the Invention) The engine 49 may be configured as an air-cooled type. In this configuration, a fan 100 for cooling the engine 49 is provided, and the radiator 101 is eliminated. The openings 95d, 86d of the right and left side panels 95, 96 may be formed not only in an elongated hexagonal shape but also in a circular shape, a rectangular shape, an elongated oval shape, a parallelogram shape, or the like.

[0194] (Tenth Alternative Embodiment of the Invention) In a riding rice transplanter equipped with a fertilizer application device 107, the seat portion 87 may be provided as a guard member for the fertilizer application device 107, the right and left side steps 48 may be eliminated, and the upper frame 90 and lower frame 89 may be eliminated.

[0195] (Eleventh Alternative Embodiment of the Invention) An electric winch (not shown) may be provided as described below. A winch frame (not shown) is attached to the front of the support frame 42 (see the above-mentioned (Overall configuration of the riding rice transplanter) and Figure 5) to extend the front position of the floor 38 upward, and the winch is attached to the top of the winch frame so that it is positioned higher than the floor 38.

[0196] If the riding rice transplanter becomes unable to move in a deep paddy field, a wire (not shown) extending from the winch can be attached to a tree or the like on the ridge, and the wire can be wound up with the winch to free the riding rice transplanter. Because the winch is located higher than the floor 38, it will not be submerged.

[0197] Of the multiple mounting members that attach the winch frame to the support frame 42, one mounting member may be configured to be slightly weaker than the other mounting members. If a large load is applied to the winch when it is used, the weak mounting member can be broken and the winch frame can be dropped off from the support frame 42, thereby preventing a large load from being applied to the support frame 42. [Industrial Applicability]

[0198] The present invention can be applied not only to riding rice transplanters, but also to riding direct seeding machines equipped with a seeding device that sows seeds on the surface of a rice field as a working device. [Explanation of symbols]

[0199] 3 Aircraft frame 3a Bottom part 3b Side part 3c Side part 3d top part 4 Link mechanism 5 Seedling planting device (work device) 15 Vertical Frame 27 Rear axle case 33 Spring support member 33a Main body 33b Mounting part 33c Mounting part 34 Suspension spring 38 floors 43 steps 44 Right step (forward step) 44j Projection 44k protrusion 45 Left step (front step) 45j protrusion 45k protrusion 46 Rear step 46d Protrusion 46e Protrusion 47 Rear step 47d Protrusion 50 Floor Frame 66 Step Frame 67 Front step frame 68 Rear step frame 79 Connecting Frame 80 Fuel Tank 81 volts 107 Fertilizer application equipment (agricultural material supply equipment)

Claims

1. An aircraft frame arranged along the front-to-rear direction; a spring bearing member attached to a rear portion of the aircraft frame; a rear axle case supporting rear wheels for driving; a suspension spring attached across the spring support member and the rear axle case; a step provided at a rear portion of the aircraft frame; A step frame that supports the step from below; a vertical frame provided so as to partially overlap the spring receiving member in a plan view, attached to the spring receiving member, and extending upward from the spring receiving member; A paddy field working machine in which the step frame is attached to the top of the vertical frame.

2. 2. The paddy field working machine according to claim 1, wherein the lower part of the vertical frame is attached across the spring receiving member and the machine body frame.

3. The spring bearing member is a main body attached to a lower portion of the body frame so as to extend rightward from a right side portion of the body frame and to extend leftward from a left side portion of the body frame; a right mounting portion attached across a portion of the main body portion extending rightward from the right side portion of the vehicle frame and the right side portion of the vehicle frame; 3. A paddy field working machine as described in claim 1 or 2, having a left mounting portion attached across a portion of the main body portion extending leftward from the left side portion of the body frame and the left side portion of the body frame.

4. A paddy field working machine as described in claim 3, wherein the lower part of the vertical frame is attached across the upper part of the body frame, the side of the body frame, and the part of the main body extending from the side of the body frame, thereby being attached across the spring support member and the body frame.

5. a floor is provided on the aircraft frame; The step is provided at a position higher than the floor, a floor frame that supports the floor from below is provided on the aircraft frame, a right connecting frame attached along the up-down direction across the right front portion of the step frame and the right rear portion of the floor frame; A paddy field working machine according to any one of claims 1 to 4, comprising a left connecting frame attached along the vertical direction across the left front portion of the step frame and the left rear portion of the floor frame.

6. A fuel tank is provided below the right front portion or the left front portion of the step frame, The paddy field working machine according to claim 5, wherein the right or left connecting frame is disposed in a vertical direction at a position laterally outside the fuel tank.

7. a plurality of protrusions protruding downward are provided on a lower portion of the step; The paddy field working machine according to any one of claims 1 to 6, wherein the step is supported by the step frame by the protrusion being placed on the step frame.

8. a downwardly recessed portion is formed in an upper portion of the protrusion; The paddy field working machine according to claim 7, wherein the step is connected to the step frame by a bolt that is inserted into the recess and attached across the protrusion and the step frame.

9. The step has a front step and a rear step connected to a rear portion of the front step, The step frame includes a front step frame that supports the front step from below, and a rear step frame that supports the rear step from below, A paddy field working machine as described in any one of claims 1 to 8, wherein the rear step and rear step frame are not provided, so that an installation area for installing an agricultural material supply device capable of supplying agricultural materials to the rice field surface is formed rearward of the front step and front step frame.

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