JP2003081140A5 - - Google Patents

Description

[Title of the Invention] Passenger-type work vehicle
[Claim of claim]
1. A front case of the transmission case disposed in the front and rear direction is provided with right and left front wheels,
Rear wheel transmission shafts are disposed in the left and right direction at the rear of the transmission case, and right and left transmission cases are supported on the right and left sides of the rear wheel transmission shafts and extended rearward, and the right and left transmissions Along with rear right and left wheels at the rear of the case
The power of the engine is transmitted to the rear wheel transmission shaft through a transmission chain disposed inside the transmission case,Via the right and left transmission casesA passenger-type work vehicle configured to be transmitted to the right and left rear wheels.
2. The passenger type working vehicle according to claim 1, further comprising a right and left side clutches capable of transmitting and disconnecting power to the right and left rear wheels on the rear wheel transmission shaft.
3. The passenger type working vehicle according to claim 1, wherein the right and left transmission cases are supported so as to be vertically pivotable independently on the rear wheel transmission shaft.
4. The power of the rear wheel transmission shaft is disposed by disposing a reduction gear for a support shaft supporting the right and left rear wheels inside the right and left transmission cases.Is theThe riding type work vehicle according to any one of claims 1 to 3, wherein power transmitted to a reduction gear and reduced in power by the reduction gear is transmitted to the support shaft.
[Claim 5]A rear wheel transmission chain is provided inside the right and left transmission cases so that engine power is transmitted to the right and left rear wheels via the rear wheel transmission chain.
Right and left portions of the rear wheel transmission shaft are projected laterally outward from the transmission case, and a sprocket gear on which the rear wheel transmission chain is wound is disposed inside the right and left transmission cases.
The right and left portions of the rear wheel transmission shaft are inserted into the right and left transmission cases and configured to be attachable to the sprocket gear,
5. The riding type according to any one of claims 1 to 4, further comprising a detent member for stopping removal of the right and left transmission cases at the right and left ends of the rear wheel transmission shaft. Work car.
6. The right and left side portions of the sprocket gear inside the right and left transmission cases are provided with bearings, and the right and left transmission cases are provided on the right and left side portions of the rear wheel transmission shaft, The passenger type working vehicle according to claim 5, which is configured to be supported via the vehicle.
7. The sprocket gear is positioned at a position where the right and left portions of the rear wheel transmission shaft can be attached when inserting the right and left portions of the rear wheel transmission shaft into the right and left transmission cases. The riding type work vehicle according to claim 5 or 6, wherein a temporary holding portion for temporarily holding the sprocket gear is provided inside the right and left transmission cases.
8. The rear wheel transmission shaft according to any one of claims 1 to 7, further comprising: right and left side brakes capable of braking the right and left rear wheels independently. Passenger type work vehicle.
9. The passenger type working vehicle according to any one of claims 1 to 8, wherein the right and left transmission cases are formed by aluminum die casting.
Detailed Description of the Invention
[0001]
Field of the Invention
The present invention relates to the configuration of a riding type work vehicle such as a riding type rice planter, a riding type direct seeding machine, or a tractor for agricultural use.
[0002]
[Prior Art]
For example, in passenger type work vehicles such as agricultural tractors, the transmission case is disposed in the front and rear direction, the right and left front wheels are provided on the front side of the transmission case, and the right and left rear wheels are provided on the rear side of the transmission case. There is.
[0003]
[Problems to be solved by the invention]
In order to be able to make a small turn at the end of the work site, it is necessary to set the maximum steering angles of the right and left front wheels to be large in a riding type work vehicle. In addition, particularly in the case of a small passenger type working vehicle, the demand for weight reduction is also high.
The present invention sets the maximum steering angles of the right and left front wheels to be large when the transmission case is arranged in the front and rear direction and the right and left front wheels are provided on the front side of the transmission case in a passenger type work vehicle The purpose is to make it possible to reduce the weight.
[0004]
[Means for Solving the Problems]
[I]
When the transmission case is arranged in the front and rear direction and the right and left front wheels are provided on the front side of the transmission case, for example, when steering the right and left front wheels to the right, the rear side of the right front wheel Since the width of the middle part of the transmission case determines the maximum steering angle of the right and left front wheels (if the width of the middle part of the transmission case is wide, the width of the middle part of the transmission case will be large. The maximum steering angles of the right and left front wheels will be small, and if the width of the middle part of the transmission case is narrow, the maximum steering angles of the right and left front wheels will be large.
[0005]
According to the first aspect of the present invention, the right and left front wheels are provided on the front side of the transmission case disposed in the front and rear direction, and the rear wheel transmission shaft is disposed in the left and right direction at the rear of the transmission case. The right and left transmission cases are supported on the left side and extended rearward, and the right and left rear wheels are provided at the rear of the right and left transmission cases. The power of the engine is transmitted to the rear wheel transmission shaft via a transmission chain disposed inside the transmission case,Through right and left transmission caseIt is configured to be transmitted to the right and left rear wheels.
[0006]
In this case, according to the feature of claim 1, the transmission chain for transmitting the motive power of the engine to the rear wheel transmission shaft is arranged to rotate around the axial center in the left-right direction. In the transmission chain that rotates around the core, a relatively large width in the vertical direction is required as a space surrounding the transmission chain, but a large width in the lateral direction is not required. Thus, the width of the middle portion of the transmission case (the portion where the transmission chain is installed) can be made narrow.
Therefore, as in the first aspect of the present invention, when the right and left front wheels are provided on the front side of the transmission case, the width of the middle portion of the transmission case (the portion where the transmission chain is installed) can be made narrow. The maximum steering angles of the right and left front wheels can be set to be large.
[0007]
[II]
According to the feature of claim 1, the power of the engine is transmitted to the rear wheel transmission shaft through the transmission chain.RightAnd is transmitted to the left rear wheel.
In the drive chainWhen configured to transmit power over a relatively long distance,Transmission chainThe middle part of the transmission case can be configured in a space where there are not many objects, so the transmission chain can be provided inside the mission case as in the first aspect of the invention.Mission case by arrangingWeight reduction.
[0008]
In this case, if the engine power is transmitted to the right and left rear wheels at once through the transmission chain, the transmission chain becomes very long. According to the feature of claim 1, the rear wheel transmission shaft functions as a relay shaft located between the engine side and the right and left rear wheels,Transmission chainIt has not been unnecessarily long.
[0009]
[III]
According to the second aspect of the present invention, as in the case of the first aspect, the "action" described in the preceding paragraph [I] [II] is provided, and in addition to this, the following "action" is provided.
Passenger type work vehicles are often equipped with right and left side clutches that can transmit and disconnect power to the right and left rear wheels. For example, the right and left front wheels are largely steered to the right (left) Then, when turning slightly to the right (left), by turning the right (left) side clutch to the disengagement side, it is possible to smoothly turn small (right) without roughening the ground.
[0010]
According to the feature of claim 2, the rear wheel transmission shaft is provided with the right and left side clutches capable of transmitting and disconnecting the power to the right and left rear wheels. Thereby, according to the feature of claim 2, the rear wheel transmission shaft can be functioned as a relay shaft positioned between the engine side and the right and left rear wheels (see the previous section [II]), right and left Can function as a support shaft for the side clutch.
[0011]
[IV]
According to the feature of claim 3, as in the case of claim 1 or 2, the "action" described in the preceding paragraph [I] [II] [III] is provided, and in addition to this, the following "action" Is equipped.
As a support structure of the right and left rear wheels, a structure is conceivable in which a rear wheel support case provided with the right and left rear wheels is supported in a rollable manner (around an axial center in the front-rear direction). According to this structure, for example, when the rear wheel support case rolls so that the right side rises and the left side descends, the contact point of the right rear wheel moves outward to the right and the right rear wheel inclines to the left inside. The left rear wheel is inclined to the left outside while the contact point of the left rear wheel moves inward to the right. For example, if both the right and left rear wheels ride on the convex part of the work site, the entire rear wheel support case will be lifted, and the passenger working vehicle will be lifted.
[0012]
According to the third aspect of the present invention, the right and left transmission cases are supported so as to freely swing up and down independently on the rear wheel transmission shaft disposed in the left and right direction. Thereby, according to the feature of claim 3, for example, the right transmission case (right rear wheel) swings upward, and the left transmission case (left rear wheel) swings downward, or the like. The unevenness of the work site is absorbed by the right and left transmission cases (right and left rear wheels), and the lateral inclination of the passenger type work vehicle is suppressed.
[0013]
According to the third aspect of the present invention, the right and left transmission cases swing up and down around the rear wheel transmission axis in the left and right direction instead of the axial center in the front and rear direction, so along with the vertical movement of the right and left transmission cases. The right and left rear wheels do not move to the right and left inside or right and left outside, and the right and left rear wheels are inclined to the right and left inside or right and left outside. Does not occur. As a result, the power of the right and left rear wheels can be transmitted to the work site (the contact points of the right and left rear wheels) without being affected by the unevenness of the workplace.
[0014]
According to the feature of claim 3, since the right and left transmission cases independently swing up and down around the rear wheel transmission shaft in the left and right direction, for example, both the right and left rear wheels ride on the projection of the work site Even if the right and left transmission cases (right and left rear wheels) swing upward, the situation in which both the right and left rear wheels ride on the projection of the work site is absorbed, The situation where the passenger type work vehicle is lifted can be suppressed.
[0015]
[V]
According to the feature of claim 4, as in the case of any one of claims 1 to 3, the "action" described in the preceding paragraphs [I] to [IV] is provided, and in addition to this, Have an “action”.
According to the feature of claim 4, the reduction gears for the support shafts for supporting the right and left rear wheels are disposed inside the right and left transmission cases, and the power of the rear wheel transmission shafts is transmitted to the reduction gears to reduce the speed. The power reduced by the gear is transmitted to the support shaft. In this case, even if the reduction gear is relatively simple and light, a relatively large reduction ratio can be obtained.
[0016]
[VI]
According to the feature of claim 5, as in the case of any one of claims 1 to 4, the "action" described in the preceding paragraphs [I] to [V] is provided, and in addition to this, Have an “action”.
According to the features of claim 5,A rear wheel transmission chain is provided inside the right and left transmission cases so that engine power is transmitted to the right and left rear wheels through the rear wheel transmission chain.When attaching the right and left transmission cases to the rear wheel transmission shaft, sprockets on which the rear wheel transmission chain and the rear wheel transmission chain are wound are arranged in advance inside the right and left transmission cases, The left transmission case is in the form of a unit assembled in advance, and the right and left portions of the rear wheel transmission shaft project laterally outward from the transmission case.
[0017]
Thus, according to the feature of claim 5, by inserting the right and left side portions of the rear wheel transmission shaft into the right and left transmission cases, the right and left side portions of the rear wheel transmission shaft are attached to the sprocket gear The right and left transmission cases are attached to the wheel transmission shaft. After that, a detent member for locking the right and left transmission cases is attached to the end of the right and left sides of the rear wheel transmission shaft.
[0018]
[VII]
According to the sixth aspect of the present invention, as in the case of the fifth aspect, the "action" described in the preceding paragraphs [I] to [VI] is provided, and in addition to this, the following "action" is provided.
According to the feature of claim 6, when configured as in the preceding paragraph [VI], bearings are provided on the right and left sides of the sprocket gear in the inside of the right and left transmission cases, and the right and left sides of the rear wheel transmission shaft By inserting the parts into the right and left transmission cases, the right and left transmission cases are supported via bearings on the right and left sides of the rear wheel transmission shaft. Thus, according to the feature of claim 6, the right (left) transmission case is supported on the right side (left side) of the rear wheel transmission shaft with a sufficient strength by the pair of bearings.
[0019]
[VIII]
According to the feature of claim 7, as in the case of claim 5 or 6, the "action" described in the preceding paragraphs [I] to [VII] is provided, and in addition to this, the following "action" is provided. ing.
According to the feature of claim 7, when the right and left portions of the rear wheel transmission shaft are inserted into the right and left transmission cases as described in the preceding paragraph [VI] [VII], according to the feature of claim 7, A temporary holding portion to be held is provided inside the right and left transmission cases, and a sprocket gear is temporarily held by the temporary holding portion at a position where the right and left portions of the rear wheel transmission shaft can be attached. Thus, according to the feature of claim 7, when the right and left portions of the rear wheel transmission shaft are inserted into the right and left transmission cases, the right and left portions of the rear wheel transmission shaft are attached to the sprocket gear without any problem. Can.
[0020]
[IX]
According to the feature of claim 8, as in the case of any one of claims 1 to 7, the "action" described in the preceding paragraphs [I] to [VIII] is provided, and in addition to this, Have an “action”.
According to the feature of claim 8, right and left side brakes capable of braking the right and left rear wheels independently are provided. Thereby, according to the feature of claim 8, for example, when the right and left front wheels are largely steered to the right (left) and turned to the right (left) in a small turn, the right (left) side brake is turned to the braking side By braking the right (left) rear wheel by operation, a small turning to the right (left) can be easily performed.
[0021]
According to the feature of claim 8, right and left side brakes capable of independently braking the right and left rear wheels are provided on the rear wheel transmission shaft. By this, according to the feature of claim 8, the rear wheel transmission shaft can be functioned as a relay shaft positioned between the engine side and the right and left rear wheels (see the preceding paragraph [II]). It can function as a support shaft for the left side brake.
[0022]
[X]
According to the feature of claim 9, as in the case of any one of claims 1 to 8, the “action” described in the preceding paragraphs [I] to [IX] is provided, and in addition to this, Have an “action”.
According to the feature of claim 9, the right and left transmission cases are formed by aluminum die casting, and the weight reduction of the right and left transmission cases is achieved.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
[1]
FIG. 1 and FIG. 2 show the whole of a riding type rice transplanter as an example of a riding type work vehicle.
As shown in FIGS. 3 and 4, the aluminum die-cast transmission case 1 is disposed to extend in the front-rear direction to the left and right center CL of the front lower side. The aluminum die-cast front wheel support case 2 is connected to the side and extended to the right and left (the front wheel support case 2 does not move up and down or roll relative to the transmission case 1). An aluminum die-cast support case 3 is rotatably supported around the vertical axis P1 of the end of the front wheel support case 2, and the right and left front wheels 4 are supported by the support case 3, and right and left The front wheel 4 is steered to the right and left around the longitudinal axis P1 (around the transmission shaft 74 in FIG. 6 described later) together with the support case 3.
[0024]
As shown in FIGS. 3 and 4, bosses 1a are formed on the right and left lateral sides of the rear end of the transmission case 1 so as to project to the right and left lateral sides. The left transmission case 5 is supported so as to freely swing up and down around the axis P2 in the left-right direction of the boss portion 1a. The right and left transmission cases 5 extend rearward from the boss portion 1a, and the right and left rear wheels 6 are supported at the rear of the right and left transmission cases 5, and the right and left rear wheels 6 are operated. It is not operated.
[0025]
As shown in FIGS. 1 and 2, a support frame 7 configured by bending a flat plate into a box shape is connected to the right and left bosses 1a, and brackets 7a are fixed to the left and right of the rear upper end of the support frame 7. A single support shaft 8 is installed across the right and left brackets 7a. Suspension springs 9 are attached across the right and left transmission cases 5 and the right and left ends of the support shaft 8. The right and left torsion bars 10 bent in a crank shape in plan view (see FIG. 4) are provided, and one end of the torsion bars 10 is connected to the rear of the transmission case 1 so as not to rotate. The other ends of the two are attached to the right and left transmission cases 5.
[0026]
Thereby, the load applied to the right and left rear wheels 6 is mainly supported by the suspension spring 9, and when the right and left transmission case 5 swings upward, the elastic resistance of the suspension spring 9 becomes right In addition to being applied to the left transmission case 5, the portion of the torsion bar 10 fixed to the transmission case 1 is twisted, and the elastic resistance of the torsion bar 10 is applied to the right and left transmission cases 5. When a force is applied to displace the right and left transmission cases 5 in the left-right direction, the torsion bar 10 suppresses the displacement of the right and left transmission cases 5 in the left-right direction.
[0027]
[2]
Next, a seedling planting apparatus 41 and a support structure of the seedling planting apparatus 41 will be described.
As shown in FIGS. 1, 2 and 3, in the support frame 7, one top link 42 is vertically pivotably supported by the support shaft 8, and right and left brackets 7 b fixed to the rear lower end of the support frame 7. The right and left lower links 43 are supported so as to be vertically swingable, and the support members 44 are connected to the rear ends of the top links 42 and the lower links 43. A single-acting elevating cylinder 45 is supported on the support shaft 8 so as to be vertically pivotable, and a cylinder rod 45a of the elevating cylinder 45 is connected to the support member 44 via a suspension rubber 46 and a V-shaped connection member 47. There is.
[0028]
As shown in FIGS. 1 and 2, a four-row planting type seedling planting apparatus 41 is rollably connected around the lower longitudinal axis of the support member 44. The seedling planting device 41 is a feed case 48 connected to the support member 44, right and left planting transmission cases 49 extended rearward, and planting that is rotationally driven by the right and left portions of the planting transmission case 49. A case 60, a pair of planting arms 50 supported by the planting case 60, a seedling platform 51 provided with four seedling surfaces and driven to reciprocate laterally in the lateral direction, and a ground float 52 supported so as to be vertically movable. Etc. are configured.
[0029]
As shown in FIGS. 3 and 4, the PTO shaft 53 extends rearward from the position shifted to the right from the left and right center CL at the upper portion of the transmission case 1 and passes through the lower portion inside the support frame 7, A universal joint 54 is provided at the end of the PTO shaft 53 in the lower vicinity between the left bracket 7b and the left bracket 7b. The PTO shaft 55 is connected across the universal joint 54 of the PTO shaft 53 and the universal joint 54 of the input shaft 48 a of the feed case 48. With the above structure, the power of the planting clutch 32 described in the following [4] [5] is transmitted to the seedling planting device 41 via the PTO shafts 53, 55, and the seedling platform 51 reciprocates As the cross feed is driven, the planting arms 50 alternately take out the seedlings from the lower part of the seedling platform 51 and plant them on the field.
[0030]
[3]
Next, the structure in the vicinity of the engine 16 and the hydrostatic stepless transmission 11 will be described.
As shown in FIGS. 1, 5 and 6, the hydrostatic continuously variable transmission 11 is positioned on the left side of the left and right center CL (see FIGS. 2 and 4) on the left lateral side of the front upper portion of the transmission case 1 It is linked as such. The input shaft 11a and the output shaft 11b of the hydrostatic continuously variable transmission 11 are positioned at substantially the same height facing in the left-right direction, and the input shaft 11a of the hydrostatic continuously variable transmission 11 protrudes leftward The output shaft 11 b of the hydrostatic continuously variable transmission 11 is located inside the transmission case 1. An outer case of the hydrostatic stepless transmission 11 is made of aluminum die cast, and an input pulley 12 and a cooling fan 13 are fixed to an input shaft 11 a of the hydrostatic stepless transmission 11.
[0031]
As shown in FIGS. 1 and 5, an engine support frame 14 directed obliquely upward and forward is connected to the front portion of the transmission case 1, and the substantially horizontal engine support base 15 is located slightly to the left of the left and right center CL Is coupled to the engine support frame 14 (see FIG. 4). The aluminum die-cast crankcase 16 a of the engine 16 is supported by the engine support 15 via the vibration-proof rubber 17, and the output shaft 16 c of the engine 16 protrudes leftward facing in the left-right direction. A die-cast cylinder 16b is disposed obliquely so as to face obliquely backward and upward.
[0032]
As shown in FIG. 5, the output pulley 18 is fixed to the output shaft 16 c of the engine 16, and the transmission belt 19 is wound around the output pulley 18 and the input pulley 12. The tension arm 20 is swingably supported around the horizontal axis P3 of the engine support frame 14, and a tension pulley 20 a is provided at the tip of the tension arm 20 so that the tension pulley 20 a is pressed against the transmission belt 19. The tension arm 20 is urged clockwise in FIG. 5 by the spring 20 b.
[0033]
[4]
Next, the transmission system to the seedling planting device 41 and the inter-strain changing mechanism 30 will be described.
As shown in FIGS. 6 and 7, in the transmission case 1, a power transmission shaft is disposed such that the power of the output shaft 11b of the hydrostatic continuously variable transmission 11 is oriented in the left-right direction and connected to the output shaft 11b. 24. A transmission gear 25 externally fitted to the transmission shaft 24 through the one-way clutch 33, a transmission gear pair 27 externally fitted rotatably relative to the transmission shaft 26 disposed in the left-right direction, transmission gear 28, transmission Transmission shaft 29 with gear 28 fixed (arranged in the left-right direction and can be rotated relative to transmission shaft 24), between-stock change mechanism 30, torque limiter 31, planting clutch 32, as described in the preceding paragraph [2] It is transmitted to the seedling planting device 41 via the PTO shafts 53 and 55 (see FIG. 3).
[0034]
As shown in FIG. 7, at the front upper portion of the transmission case 1, the transmission shafts 23 and 29 are supported so as to protrude outward from the right outer wall 1 b of the transmission case 1, and the projecting portion of the transmission shaft 29 The three transmission gears 21 are externally fitted rotatably in a key structure with the key structure, and the three transmission gears 22 are fitted relatively rotatably to the projecting portion of the transmission shaft 23, and the transmission gears 21 and 22 are There are three sets of transmission gears 21 and 22 engaged with each other. Three cam balls 34 movable in the radial direction of the transmission shaft 23 are disposed in each of the transmission gears 22, and a shift rod 35 slidably movable in the axial center direction of the transmission shaft 23 is provided. The inter-share changing mechanism 30 is configured as described above.
[0035]
As shown in FIG. 7, the vertical wall 1 c is formed on the right outer wall 1 b of the transmission case 1, and the stock change mechanism 30 is surrounded by the vertical wall 1 c of the transmission case 1. The wall portion 1 c is provided with a lid portion 57 which is detachable by a bolt 56. The shift rod 35 is slidably supported by the lid portion 57, and the lid portion 57 is provided with a detent ball 58 for holding the shift rod 35 in three positions.
[0036]
Thereby, as shown in FIG. 7, when the shift rod 35 is slide-operated to position the large diameter portion of the tip of the shift rod 35 on the cam ball 34 corresponding to the desired transmission gear 22, the large diameter of the shift rod 35 is obtained. The cam ball 34 is pushed out in the radial direction of the transmission shaft 23 by the portion to enter the opening of the transmission shaft 23 and the desired transmission gear 22, and the desired transmission gear 22 is fixed to the transmission shaft 23 The power of the transmission shaft 29 is transmitted to the transmission shaft 23 via the desired transmission gear 22. As described above, by positioning the large diameter portion of the shift rod 35 on the desired cam ball 34 (transmission gear 22), the power transmitted from the transmission shaft 29 to the transmission shaft 23 is changed into three steps, and the planting arm 50 (see Figure 1 and Figure 2) changes the interval of seedlings planted on the field in 3 stages.
[0037]
In this case, the stock change mechanism 30 can be opened by removing the bolt 56 and removing the shift rod 35 together with the lid 57. As a result, the transmission gears 21 and 22 are removed from the transmission shafts 23 and 29 and the transmission gears 21 and 22 having different numbers of teeth are attached to the transmission shafts 23 and 29 to change the stock ratio of another specification having different transmission ratios. It can be changed to 30.
[0038]
[5]
Next, the torque limiter 31 and the planting clutch 32 will be described.
As shown in FIG. 7, the output shaft 36 is disposed in the front-rear direction at a position deviated to the right from the left and right center CL at the top of the transmission case 1, and the PTO shaft 53 is placed on the output shaft 36 outside the transmission case 1. (See FIG. 3 and FIG. 4) are connected. Inside the transmission case 1, a cylindrical shaft 37 is fitted on the output shaft 36 so as to be relatively rotatable, and a bevel gear 38 fitted on the cylindrical shaft 37 so as to be relatively rotatable is engaged with the bevel gear 39 fixed to the transmission shaft 23. doing. The engaging portion 40 is externally fitted integrally with the cylindrical shaft 37 in a spline structure so as to be rotatable integrally and slidably, the spring receiving and rotating portion 59 is fixed to the cylindrical shaft 37, and a spring biasing the engaging portion 40 to the bevel gear 38 61 is provided between the engaging portion 40 and the spring receiving and rotating portion 59. The torque limiter 31 is configured as described above.
[0039]
As shown in FIG. 7, the engaging portion 62 is externally fitted with a spline structure so as to be integrally rotatable and slidably on the output shaft 36, and provided with a spring 63 for urging the engaging portion 62 against the spring receiving and rotating portion 59. The planting clutch 32 is configured. The state shown in FIG. 7 is a state in which the notch formed in the outer peripheral portion of the engaging portion 40 is engaged with the convex portion of the bevel gear 38, and the convex portion of the engaging portion 62 is a spring receiving rotating portion It is in the state of being located in the engagement position which enters into the opening of 59 and engages. In this state, the power of the inter-roll changing mechanism 30 is transmitted to the PTO shaft 53 via the bevel gear 38, the engaging portion 40, the cylindrical shaft 37, the spring receiving and rotating portion 59, the engaging portion 62 and the output shaft 36.
[0040]
In the above-mentioned state, when a large load is applied to the seedling planting device 41, the engaging portion 40 slides against the biasing force of the spring 61 to separate from the bevel gear 38, and between the bevel gear 38 and the engaging portion 40. The power is shut off and the seedling planting device 41 is stopped. When the large load applied to the seedling planting device 41 disappears, the engaging portion 40 slides to the bevel gear 38 by the biasing force of the spring 61, and the notch portion of the engaging portion 40 enters the convex portion 38a of the bevel gear 38 and engages. The power is automatically returned to the state where power is transmitted, and the seedling planting device 41 operates.
[0041]
As shown in FIG. 7, when the operating rod 64 is slid to the left in the drawing, the operating rod 64 enters the cam surface formed on the side of the engaging portion 62, and the engaging portion 62 is in a predetermined phase (planting arm The slide operation is performed at a phase 50 (see FIG. 1) located above the rice field and separated from the spring receiving and rotating portion 59. As a result, the power is cut off between the spring receiving and rotating portion 59 and the engaging portion 62, and the seedling planting device 41 is stopped.
[0042]
[6]
Next, the transmission system to the right and left front wheels 4 will be described.
As shown in FIGS. 6, 7 and 8, transmission gears 65 and 66 are fixed to the transmission shaft 24, and a shift gear 67 is externally fitted to the transmission shaft 26 rotatably and slidably integrally with the transmission shaft 26 by a spline structure. The right and left front wheel transmission shafts 68 are disposed in the left-right direction across the transmission case 1 and the right and left front wheel support cases 2, and the buttocks of the right and left front wheel transmission shafts 68 are arranged inside the transmission case 1. In the part, a front wheel differential mechanism 69 is provided.
[0043]
As shown in FIG. 8, a front wheel differential mechanism 69 is constituted by an outer case 69a, a pair of pinion gears 69b rotatably supported by the outer case 69a, and a pair of side gears 69c engaged with the pinion gear 69b. The right and left front wheel transmission shafts 68 are connected to the left side gear 69c. The cylindrical shaft 70 connected to the outer case 69 a of the front wheel differential mechanism 69 is fitted on the right front wheel transmission shaft 68 so as to be relatively rotatable, and the transmission gear 71 fixed to the cylindrical shaft 70 is connected to the transmission shaft 26. It is engaged with the fixed transmission gear 72.
[0044]
With the above structure, as shown in FIGS. 6, 7 and 8, by sliding the shift gear 67 and engaging the transmission gears 65 and 66, the power of the transmission shaft 24 is shifted in two steps and transmitted to the transmission shaft 26. Be done. Power of transmission shaft 26 is transmission gears 72 and 71, cylindrical shaft 70, front wheel differential mechanism 69, right and left front wheel transmission shaft 68, bevel gear mechanism 73 incorporated in front wheel support case 2, front wheel support case 2 and support case 3 The transmission shaft 74 is transmitted to the right and left front wheels 4 via the transmission shaft 74, the bevel gear mechanism 75 incorporated in the support case 3 and the support shaft 4a.
[0045]
As shown in FIG. 8, the shift member 76 is externally fitted to the right front wheel transmission shaft 68 so as to be integrally rotatable and slidable with the right front wheel transmission shaft 68 by the key structure, and the shift member 76 is separated from the cylindrical shaft 70 A spring 77 biasing the side and an operation shaft 78 sliding the shift member 76 on the cylindrical shaft 70 are provided. As a result, as shown in FIG. 8, when the operating shaft 78 is rotationally operated and the shift member 76 is slid to the left in the drawing so that the end of the cylindrical shaft 70 is engaged, the front wheel differential mechanism 69 is in the differential lock state. When the shift member 76 is separated from the end of the cylindrical shaft 70, the front wheel differential mechanism 69 is in the differential lock release state.
[0046]
[7]
Next, the transmission system to the right and left rear wheels 6 will be described.
As shown in FIGS. 9 and 10, right and left rear wheel transmission shafts 79 are supported by a pair of bearings 103 in each of the bosses 1a of the transmission case 1, and the right and left rear wheel transmission shafts 79 are It is matched. Right and left rear wheel transmission shafts 79 project laterally outward from the boss portion 1a of the transmission case 1, and transmit right and left transmissions to the right and left rear wheel transmission shafts 79 (axial center P2 in the left-right direction). The case 5 is supported so as to freely swing up and down. As shown in FIGS. 6 and 8, a sprocket gear 80 is fixed to the cylindrical shaft 70, and as shown in FIGS. 9 and 10, in the butt portion of the right and left rear wheel transmission shaft 79 inside the transmission case 1, Sprocket gear 81 is relatively rotatably fitted over, and transmission chain 82 is wound around sprocket gears 80 and 81.
[0047]
As shown in FIG. 9 and FIG. 10, the right and left shift members 83 are externally fitted rotatably and slidably to the right and left rear wheel transmission shafts 79 in a spline structure, and the right and left rear wheel transmission shafts A plurality of friction plates 84 are disposed between 79 and the boss portion 1 a of the transmission case 1, and a spring 85 is provided to bias the right and left shift members 83 to the sprocket gear 81. A shift arm 88 is provided for sliding the right and left shift members 83 to the friction plate 84, and a steering handle 89 (see FIGS. 1 and 5) for steering the right and left front wheels 4; The left shift arm 88 is mechanically linked. Thereby, the right and left side clutches 86 are formed between the sprocket gear 81 and the right and left shift members 83, and between the right and left shift members 83 and the friction plate 84, the right and left A side brake 87 is configured.
[0048]
In the states shown in FIGS. 9 and 10, the right and left front wheels 4 are steered within the range of the right and left set angles from the straight movement position and the straight movement position, respectively. A state 83 is engaged with the sprocket gear 81 (the right and left side clutches 86 are operated to the transmission side and the right and left side brakes 87 are operated to the release side). Thus, the power of the cylindrical shaft 70 (see FIGS. 6 and 8) is transmitted by the transmission chain 82, the sprocket gear 81, the right and left shift members 83, the right and left rear wheel transmission shafts 79, and the right and left transmission cases. It is transmitted to the right and left rear wheels 6 via the rear wheel transmission chain 90 and the transmission shaft 91, which are internally mounted to the vehicle 5, and the support shaft 6a.
[0049]
For example, when the steering handle 89 is operated to the right and the right and left front wheels 4 are steered to the right beyond the set angle to the right, the right shift member 88 resists the spring 85 and the right shift member The slide 83 is moved to the right in the drawing of FIG. 10 so as to be separated from the sprocket gear 81 and press the right friction plate 84. Thus, the right rear wheel 6 is braked (the right side brake 87 is braked in a state where the power to the right rear wheel 6 is cut off (the right side clutch 86 is operated to the cut-off side) Operated by the side).
[0050]
As shown in FIGS. 6 and 10, the outer surface on the right side of the middle portion of the transmission case 1 is formed with a recess 1d opened laterally outward, and a wall 1e and a boss 1f forming a periphery of the recess 1d are transmissions. The boss 1 f is integrally formed on the left outer surface of the middle portion of the transmission case 1. As shown in FIGS. 6, 10 and 11, the intermediate shaft 92 is rotatably supported over the right and left bosses 1f, and the sprocket gear 92a formed on the intermediate shaft 92 is wound around the transmission chain 82 inside the winding path. And a brake 94 capable of braking the intermediate shaft 92 is disposed so as to enter the recess 1d.
[0051]
As shown in FIGS. 6, 10 and 11, the guide chain 93 prevents the separation of the transmission chain 82 from the sprocket gear 92a, and the winding of the transmission chain 82 is performed so that the transmission chain 82 is sandwiched between the sprocket gear 92a and the guide member 93. It is arranged outside the circuit. With the above structure, by operating the brake 94 to the braking side, the right and left front wheels 4 and the right and left rear wheels 6 are braked via the intermediate shaft 92, the sprocket gear 92a, and the transmission chain 82.
[0052]
[8]
Next, the structure of the right and left transmission cases 5 will be described.
As shown in FIG. 10 and FIG. 13 (A) (B), the transmission case 5 on the right and the left is constructed in a two-piece structure by an outer case 5 a and an inner case 5 b made of aluminum die cast. As described above, at the rear of the right and left transmission case 5, the support shaft 6 a is supported by a pair of bearings 104, and the transmission shaft 91 is supported by a pair of bearings 105. The transmission shaft 91 is provided with a small diameter transmission gear 91a, and the large diameter transmission gear 6b fixed to the support shaft 6a is engaged with the transmission gear 91a.
[0053]
As shown in FIG. 12 and FIG. 13 (i) (ii) (b), an opening 5c is formed on the lateral side of the front of the right and left transmission case 5, and the bearing 106 is formed on the outer and inner cases 5a, 5b. The cylindrical shaft 107 is disposed between the bearings 106 and mounted concentrically with the opening 5 c. A small diameter sprocket gear 107 a is provided on the outer surface of the cylindrical shaft 107, and a spline portion 107 b is formed on the inner surface of the cylindrical shaft 107. As shown in FIG. 9, a sprocket gear 91b having a large diameter is fixed to the transmission shaft 91, and a rear wheel transmission chain 90 is wound around the sprocket gears 107a and 91b. As shown in FIG. 12, a spline portion 79a is formed on the right and left rear wheel transmission shafts 79, and a threaded portion 79b is provided on the spline portion 79a.
[0054]
As shown in FIG. 12 and FIG. 13 (A) (B), convex temporary holding portions 5 d, 5 e are integrally formed on the inner surface of the front of the right and left transmission case 5. The temporary holding portion 5d is disposed so as to enter inside the winding path of the rear wheel transmission chain 90, and is disposed with a slight gap so as to face the sprocket gear 107a. The temporary holding portion 5 e is disposed with a slight gap so as to be located outside the winding path of the rear wheel transmission chain 90, and is disposed so as to face the rear wheel transmission chain 90.
[0055]
With the above structure, as shown in FIG. 12, in the state where the right and left transmission cases 5 are not attached to the right and left rear wheel transmission shafts 79, the sprocket gear 107a or the rear wheel transmission chain 90 is a temporary holding portion 5d, The cylindrical shaft 107 is temporarily held in a position substantially concentric with the opening 5c in contact with the member 5e. Next, as shown in FIGS. 12 to 10, when the spline portion 79a is inserted into the cylindrical shaft 107 (spline portion 107b) and the bearing 106 from the inner opening 5c, the right and left rear wheel transmission shafts 79 (spline portions) 79a) is attached to the cylindrical shaft 107 (spline portion 107b), and the pair of bearings 106 support the right and left transmission cases 5 on the right and left rear wheel transmission shafts 79. As described above, with the right and left rear wheel transmission shafts 79 (spline portions 79a) attached to the cylindrical shaft 107 (spline portions 107b), the sprocket gear 107a and the rear wheel transmission chain 90 are temporarily held by the holding portions 5d, 5e. Leave from
[0056]
Next, as shown in FIGS. 10 and 12, the receiving plate 108 is attached to the screw portion 79b from the outer opening 5c, and the nut 109 is tightened to the screw portion 79b. Make sure that the left transmission case 5 does not come off. Finally, the cap 110 is attached to the outer opening 5c.
[0057]
[First alternative embodiment of the invention]
The right and left side clutches 86 and the right and left side brakes 87 of the above-mentioned embodiment of the invention may be disposed on the left front wheel transmission shaft 68 as shown in FIGS. 14 and 15.
As shown in FIGS. 14 and 15, a front wheel differential mechanism 69 is provided at the butting portion of the right and left front wheel transmission shafts 68 inside the transmission case 1, and rotation and slide integrally with the right front wheel transmission shaft 68 by the key structure. The spring 77 and the shift member 76 are freely fitted on the right front wheel transmission shaft 68 to urge the shift member 76 away from the outer case 69 a of the front wheel differential mechanism 69. An operating shaft 78 is provided to slide on the outer case 69a. Thereby, when the shift member 76 is separated from the outer case 69a of the front wheel differential mechanism 69, the front wheel differential mechanism 69 is in the differential lock released state, and the operation shaft 78 is rotated to shift the shift member 76 to the left in the drawing. When the slide operation is performed and the outer case 69a of the front wheel differential mechanism 69 is engaged, the front wheel differential mechanism 69 is in the differential lock state.
[0058]
As shown in FIGS. 14 and 15, the cylindrical shaft 70 connected to the outer case 69a of the front wheel differential mechanism 69 is fitted on the left front wheel transmission shaft 68 so as to be relatively rotatable and fixed to the cylindrical shaft 70. The transmission gear 96 is engaged with the transmission gear 72. The right and left cylindrical shafts 95 are relatively rotatably fitted on the cylindrical shaft 70, and the right and left shift members 97 are integrally rotatably and slidably fitted on the right and left cylindrical shafts 95 by the key structure. A plurality of friction plates 98 are disposed between the right and left cylindrical shafts 95 and the transmission case 1. Thus, the right and left side clutches 86 are formed between the transmission gear 96 and the right and left shift members 97, and between the right and left shift members 97 and the friction plate 98, the right and left A side brake 87 is configured.
[0059]
As shown in FIGS. 14 and 15, the right and left rear wheel transmission shafts 79 are disposed in the left-right direction across the boss portion 1a of the transmission case 1 and the right and left transmission cases 5; The right and left transmission cases 5 are supported by the left rear wheel transmission shaft 79 (the axial center P2 in the left-right direction) so as to be vertically swingable. An intermediate shaft 99 is supported by the transmission case 1, and a transmission gear 100 externally fitted to the intermediate shaft 99 is engaged with the transmission gear 101 fixed to the right and left rear wheel transmission shafts 79. A transmission chain 102 is wound around sprocket gears 95 a provided on the right and left cylindrical shafts 95 and a sprocket gear 100 a fixed to the transmission gear 100.
[0060]
With the above-described structure, as shown in FIGS. 14 and 15, the power of the transmission shaft 26 is transmitted to the right and left front wheels 4 via the transmission gears 72 and 96, the cylindrical shaft 70, and the front wheel differential mechanism 69. In the states shown in FIGS. 14 and 15, the right and left front wheels 4 are steered within the range of the right and left set angles from the straight ahead position and the straight ahead position, and the right and left shift members 97 is engaged with the transmission gear 96 (the right and left side clutches 86 are operated to the transmission side, and the right and left side brakes 87 are operated to the release side). Thus, the power of the transmission gear 96 is transmitted via the right and left shift members 97, the transmission chain 102, the right and left rear wheel transmission shafts 79, and the rear wheel transmission chain 90 incorporated in the right and left transmission cases 5. It is transmitted to the right and left rear wheels 6.
[0061]
For example, when the steering handle 89 is operated to the right and the right and left front wheels 4 are steered to the right beyond the set angle of the right, the right shift member 97 slides to the right in the drawing of FIG. Then, it separates from the transmission gear 96 and presses the right friction plate 98. Thus, the right rear wheel 6 is braked (the right side brake 87 is braked in a state where the power to the right rear wheel 6 is cut off (the right side clutch 86 is operated to the cut-off side) Operated by the side).
[0062]
Second Embodiment of the Invention
In the above-mentioned [Embodiments of the Invention] and [First Embodiment of the Invention], when the outer and inner cases 5a, 5b are connected to obtain the right and left transmission cases 5, the outer and inner cases 5a, The outer peripheral part of 5b is connected by a bolt.
In this case, since the central portions of the outer and inner cases 5a and 5b are not particularly disposed inside the winding path of the rear wheel transmission chain 90, as shown in FIG. 16 (a), the outer and inner cases 5a , 5b may be connected by bolts 111, and the number of bolts 111 connecting the outer peripheral portions of the outer and inner cases 5a, 5b may be reduced. Further, as shown in FIG. 16 (b) (c), an opening 5f penetrating in the central portion of the outer and inner cases 5a, 5b is formed, and the outer periphery of the outer and inner cases 5a, 5b, the outer and inner cases The outer peripheral portions of the openings 5 f of 5 a and 5 b may be connected by bolts 111.
[0063]
[Third Embodiment of the Invention]
In the above-described [Invention embodiment], [First alternative embodiment of the invention] and [Second alternative embodiment of the invention], the right and left side brakes 87 are eliminated and the right and left side clutches are eliminated. It may be configured to include only 86. Conversely, the right and left side clutches 86 may be eliminated to provide the right and left side brakes 87 and a rear wheel differential mechanism (not shown).
[0064]
In the above-described embodiment of the invention, the transmission chain 82 shown in FIGS. 6 and 9 may be wound around the transmission shaft 26 and the sprocket gear 81. In the first embodiment of the invention, the transmission chain 102 shown in FIGS. 14 and 15 may be wound around the transmission shaft 26 and the sprocket gear 100a.
The present invention can be applied not only to a riding type rice transplanter but also to a four wheel drive type riding type direct seeding machine provided with a direct seeding device at the rear and capable of moving up and down, a four wheel drive type agricultural tractor and a riding type lawn mower.
[0065]
【Effect of the invention】
According to the first aspect of the present invention, in the passenger type work vehicle, when the transmission case is disposed in the front and rear direction and the right and left front wheels are provided on the front side of the transmission case, the middle portion of the transmission case Part) can be made narrow, and the maximum steering angle can be set to a large value for steering the right and left front wheels until they touch the middle part of the transmission case, It has been possible to improve the turning performance of mold working vehicles.
[0066]
According to the features of claim 1, inside the mission caseMission case by arranging the transmission chainIn particular, the traveling performance of the passenger type working vehicle in a soft work place such as a paddy field can be improved.
In this case, according to the feature of claim 1, the rear wheel transmission shaft functions as a relay shaft located between the engine side and the right and left rear wheels,Transmission chainIs not unnecessarily long, soTransmission chainIt does not involve the reduction of the transmission efficiency of the
[0067]
According to the feature of claim 2, the "effect of the invention" of the above-mentioned claim 1 is provided as in the case of the claim 1, and in addition to the "effect of the invention", the following "effect of the invention" Is equipped.
According to the feature of claim 2, when the right and left side clutches capable of transmitting and disconnecting power to the right and left rear wheels are provided, by providing the right and left side clutches on the rear wheel transmission shaft, The rear wheel transmission shaft can function as a relay shaft positioned between the engine side and the right and left rear wheels, can function as a support shaft for the right and left side clutches, and the structure is simplified. In terms of
[0068]
According to the feature of claim 3, as in the case of claim 1 or 2, the "effect of the invention" of the above-mentioned claim 1 or 2 is provided, and in addition to the "effect of the invention" "Effects of the Invention" is provided.
According to the feature of the third aspect, while suppressing the left-right inclination of the passenger type work vehicle, the power of the right and left rear wheels is not wasted without being affected by the unevenness of the work site, and the work site (right and left rear wheels Was able to improve the running performance of the passenger type work vehicle.
According to the feature of claim 3, for example, even if both the right and left rear wheels ride on the convex part of the work site, the right and left transmission cases (right and left rear wheels) swing upward, The situation in which both the right and left rear wheels ride on the convex part of the work place is absorbed, and the situation where the passenger type work vehicle is lifted is suppressed, so the traveling performance of the passenger type work vehicle is improved in this point as well. I was able to
[0069]
According to the feature of claim 4, the “effect of the invention” of the above-mentioned claims 1 to 3 is provided as in the case of any one of claims 1 to 3, and in addition to this “effect of the invention” The following “effects of the invention” are provided.
According to the feature of claim 4, it is possible to utilize a point that a relatively large reduction ratio can be obtained even with a relatively simple and light reduction gear.More than enoughIt is possible to reduce the transmission ratio of the right and left transmission cases, and to improve the running performance of the passenger type work vehicle especially in a soft work place such as a paddy field. I was able to.
[0070]
According to the feature of claim 5, as in the case of any one of claims 1 to 4, the “effect of the invention” of the above-mentioned claims 1 to 4 is provided, and in addition to this “effect of the invention” The following “effects of the invention” are provided.
According to the feature of claim 5, by inserting the right and left portions of the rear wheel transmission shaft into the right and left transmission cases, the right and left portions of the rear wheel transmission shaft are attached to the sprocket gear, and the rear wheel transmission shaft The right and left transmission cases can be attached as a unit by attaching the right and left transmission cases to each other, and the assemblability can be improved.
[0071]
According to the feature of claim 6, the “effect of the invention” of the above-mentioned claim 5 is provided as in the case of the claim 5, and in addition to the “effect of the invention”, the following “effect of the invention” Is equipped.
According to the feature of claim 6, the right (left) transmission case is supported with sufficient strength by the pair of bearings on the right side (left side) of the rear wheel transmission shaft, and the strength of the passenger type work vehicle It became advantageous in terms of securing.
[0072]
According to the feature of claim 7, the “effect of the invention” of the above-mentioned claim 5 or 6 is provided as in the case of the claim 5 or 6, and in addition to the “effect of the invention” "Effects of the Invention" is provided.
According to the feature of claim 7, the right and left portions of the rear wheel transmission shaft are inserted into the right and left transmission cases by providing temporary holding portions for temporarily holding the sprocket gears inside the right and left transmission cases. In this case, since the right and left portions of the rear wheel transmission shaft can be attached to the sprocket gear without any trouble, the assemblability can be improved.
[0073]
According to the feature of claim 8, as in the case of any one of claims 1 to 7, the “effect of the invention” of the above-mentioned claims 1 to 7 is provided, and in addition to this “effect of the invention” The following “effects of the invention” are provided.
According to the feature of claim 8, in the case of providing the right and left side brakes capable of independently braking each of the right and left rear wheels, the rear wheel transmission can be performed by providing the right and left side brakes on the rear wheel transmission shaft. The shaft can function as a relay shaft located between the engine side and the right and left rear wheels, can function as a support shaft for the right and left side brakes, and in terms of simplification of the structure. It became an advantage.
[0074]
According to the feature of claim 9, as in the case of any one of claims 1 to 8, the “effect of the invention” of the above-mentioned claims 1 to 8 is provided, and in addition to this “effect of the invention” The following “effects of the invention” are provided.
According to the feature of claim 9, by configuring the right and left transmission cases by aluminum die casting, it is possible to reduce the weight of the right and left transmission cases, especially in a soft work place such as a paddy field or the like. The driving performance of the passenger type work vehicle was able to be improved.
Brief Description of the Drawings
[Fig. 1] Overall side view of a riding type rice transplanter
[Fig. 2] Overall plan view of the riding type rice transplanter
[FIG. 3] Side view in the vicinity of the transmission case, front wheel support case, transmission case, support frame, top link and lower link
FIG. 4 is a plan view of the vicinity of the transmission case, the front wheel and the front wheel support case, the rear wheel and the transmission case.
[FIG. 5] Side view of the vicinity of the engine and hydrostatic stepless transmission
FIG. 6 is a cross-sectional plan view of the front of the transmission case and near the front wheel support case
[FIG. 7] Transverse plan view of the front of the transmission case
[FIG. 8] Cross-sectional plan view near the front wheel differential mechanism of the transmission case
[FIG. 9] Transverse plan view of the rear of the transmission case and in the vicinity of the transmission case
[FIG. 10] Transverse plan view near the rear of the transmission case
[Figure 11] Longitudinal side view of transmission case of transmission case
FIG. 12 is a transverse plan view showing how the right and left transmission cases are attached to the right and left rear wheel transmission shafts.
FIG. 13 is a view showing the inside of the outer and inner cases in the right and left transmission cases
FIG. 14 is a cross-sectional plan view in the vicinity of the transmission case in the first alternative embodiment of the invention;
FIG. 15 is a cross-sectional plan view near the front of the transmission case in a first alternative form of implementation of the invention;
FIG. 16 is a side view of the right and left transmission cases in a second alternative embodiment of the invention;
[Description of the code]
1 Mission case
4 front wheel
5 Transmission case
5d, 5e temporary holder
6 rear wheel
6a Support shaft
16 engine
79 Rear wheel transmission shaft
82 Transmission Chain
86 side clutch
87 Side brake
90 rear wheel drive chain
91 Reduction gear
106 bearings
107a Sprocket gear
109 Locking member