JP2022127263A - work vehicle - Google Patents

Abstract

To provide a work vehicle equipped with: wheels supported on both lateral end parts of a wheel driving case, a gear mechanism stored in an intermediate part in a lateral width direction of the body of the wheel driving case, which transmits power to the wheels supported on both lateral end parts; and an air-bleeding part that performs air-bleeding from the inside to the outside of the wheel driving case, the work vehicle being configured to prevent clogging of the air-bleeding part caused by mud spattered by the wheels and a lubricant spattered by a gear, while simplifying a countermeasure structure for preventing clogging.SOLUTION: A work vehicle is provided with: a cylindrical part 21 which is provided protruding from an intermediate part of a wheel driving case 14 toward outside of the wheel driving case 14, and through which an input shaft 19 of a gear mechanism 20 is inserted; and a bearing 22a provided between the cylindrical part 21 and the input shaft 19. An air-bleeding part 27 is opened to the inside of the cylindrical part 21, at a site positioned closer to a protruding side of the cylindrical part 21 than the bearing 22a, of the cylindrical part 21.SELECTED DRAWING: Figure 4

Description

The present invention relates to work vehicles.

The work vehicle includes a wheel drive case supported by the traveling machine body in a state extending in the machine body width direction, wheels supported on both side ends of the wheel drive case, and a middle part of the wheel drive case in the machine body width direction. a gear mechanism received and transmitting power to said wheels at both lateral ends. As this type of working vehicle, for example, there is a riding-type rice transplanter disclosed in Patent Document 1. The riding-type rice transplanter disclosed in Patent Document 1 includes a rear axle case as a wheel drive case and rear wheels as wheels, and has a bevel gear fixed to an input shaft and a bevel gear fixed to a transmission shaft. mechanism is provided.

JP 2013-203359 A

In the above-described work vehicle, if an air release portion for releasing air from the inside of the wheel drive case to the outside is provided at the lateral end of the wheel drive case, mud splashed by the wheels will be discharged through the air discharge port of the air release portion. It gets in and clogs the air release part. In order to prevent clogging of the air vent by mud splashed by the wheels, even if the air vent is provided in the middle part of the wheel drive case, lubricating oil stored inside the wheel drive case will cause the gear mechanism to rotate. If it is blown away by the agitation by the gear and enters the air vent, the air vent will be clogged.

To provide a work vehicle capable of preventing clogging of an air vent part by mud splashed by wheels and lubricating oil blown by gears, and having a simple structure for preventing clogging.

A work vehicle according to the present invention comprises:
a wheel drive case supported by the traveling body in a state extending in the width direction of the body;
wheels supported on both lateral ends of the wheel drive case;
a gear mechanism housed in an intermediate portion of the wheel drive case in the lateral width direction of the vehicle body and transmitting power to the wheels at both lateral ends;
a cylindrical portion protruding from the intermediate portion of the wheel drive case toward the outside of the wheel drive case and through which the input shaft of the gear mechanism is inserted;
a bearing provided between the cylindrical portion and the input shaft in a state of being externally fitted on the input shaft and internally fitted on the cylindrical portion;
an air bleeding portion for bleeding air from the inside of the wheel drive case to the outside,
The air release portion communicates with the inside of the cylindrical portion,
The opening of the air vent portion in the tubular portion is arranged at a portion of the tubular portion located closer to the projecting end side of the tubular portion than the bearing.

According to this configuration, the air discharge port of the air bleeder can be easily arranged at a position away from the wheel in the widthwise direction of the fuselage compared to providing the air bleeder at the end of the wheel drive case in the widthwise direction of the fuselage. Even if the mud is thrown off by the wheels, it does not easily enter the air discharge port, and clogging of the air venting part by mud thrown off by the wheels can be prevented. Even if the lubricating oil stored inside the wheel drive case is stirred by the rotating gears of the gear mechanism, the lubricating oil is prevented from hitting the bearings and entering the opening in the cylindrical portion of the air vent. Therefore, it is possible to prevent clogging of the air vent portion due to lubricating oil blown by the gear.

A bearing that enables smooth rotation of the input shaft relative to the cylinder is used as a member to prevent lubricating oil from entering the opening of the air vent. A simple structure in which the air release portion is opened at a portion of the interior of the portion located on the protruding end side of the cylindrical portion relative to the bearing is sufficient.

In the present invention,
A second bearing that fits externally on the input shaft and internally fits on the cylindrical portion is located between the input shaft and a portion of the cylindrical portion located closer to the projecting end than the portion where the opening is located. Preferably provided.

According to this configuration, the second bearing prevents muddy water or the like from entering the opening of the cylinder portion of the air vent portion from the outside of the cylinder portion. It is possible to prevent clogging due to muddy water, etc. in the air vent while simplifying the structure of the air vent to prevent clogging by utilizing the bearing.

In the present invention,
It is preferable that the air release portion has a bendable pipe portion.

According to this configuration, even if there is a member such as a transmission system near the cylindrical portion, the air vent can be arranged in a state in which the member is bypassed by the bending of the pipe portion, so that the air discharge port of the air vent can be positioned at a desired location. Easy to place.

In the present invention,
The wheel drive case includes a middle case portion extending in the width direction of the machine body and including the cylindrical portion; and a horizontal case portion facing up and down, wherein the oil supply port for supplying lubricating oil to the inside of the wheel drive case is located at a position higher than the center of the middle case portion in the vertical direction of the aircraft body. is preferably provided on at least one of the lateral case portions of the portion.

According to this configuration, the amount of lubricating oil that can satisfy the amount of oil required to be stored in the wheel drive case, that is, the position of the oil surface of the lubricating oil stored in the wheel drive case and the center of the wheel drive case. Both lubricating oils having the same position can be supplied from at least one of the lateral case portions.

In the present invention,
It is preferable that the fuel filler port is provided in both of the lateral case portions of the both end portions.

With this configuration, even if an obstacle such as a wall is located on one side of the fuselage, it is possible to use the lubrication port located on the side of the side case that is opposite to the side where the obstacle is located. Easy to replenish. When there are no obstacles on both lateral sides of the machine body, lubricating oil can be replenished quickly because the refueling ports on both the left and right lateral cases can be used.

In the present invention,
It is preferable that the wheel drive case is provided at the rear part of the traveling machine body, and the fuel filler port is provided at a rear facing part of the outer peripheral part of the horizontal case part.

According to this configuration, since the oil filler port faces the empty space behind the wheel drive case, it is easy to fill the oil filler port with lubricating oil.

It is a left view which shows the whole ride-on type rice transplanter. It is a front view showing a wheel drive case. It is a rear view showing a wheel drive case. FIG. 4 is a side view showing a gear mechanism, an input shaft and an air bleeder; It is a left view which shows a fuel filler port. It is a left view which shows the air bleeding part provided with another embodiment.

An embodiment, which is an example of the present invention, will be described below with reference to the drawings.
1 and 4, the direction of arrow F shown in FIGS. 1 and 4 is the "body front", and the direction of arrow B is the "body rear". , the direction of arrow U is defined as "above the body", the direction of arrow D is defined as "below the body", the direction to the front side of the paper surface of FIGS.

[Overall riding type rice transplanter]
As shown in FIG. 1, the riding rice transplanter has a traveling body 3 having a pair of left and right front wheels 1 and a pair of left and right rear wheels 2 . A driving unit 5 having an engine 4 is formed in the front part of the traveling body 3 . A driving section 8 having a driver's seat 6 and a steering wheel 7 for steering the front wheels 1 is formed in the rear portion of the traveling body 3 . A seedling planting device 9 is connected to the rear portion of the traveling body 3 . The seedling planting device 9 is connected to the traveling body 3 via a link mechanism 11 extending rearward from the body frame 10 so as to be vertically swingable. In the seedling planting device 9, the link mechanism 11 is oscillated by the extension and contraction of the elevating cylinder 12, whereby the ground float 9a is in contact with the field and the ground float 9a is in a downward working state and an upward state with respect to the field. and a non-working state spaced apart from each other. The seedling planting device 9 has six seedling planting mechanisms 9b arranged in the width direction of the traveling body 3, and is configured to be capable of planting seedlings on six planting rows.

The pair of left and right front wheels 1 are supported on the front part of the body frame 10 via a front transmission case 13 that supports the pair of left and right front wheels 1 in a steerable and driveable manner. The pair of left and right rear wheels 2 are supported on the rear portion of the body frame 10 via a wheel drive case 14 that drivably supports the pair of left and right rear wheels 2 . The output of the engine 4 is input to the front transmission case 13, and the input power is transmitted to the left and right front wheels 1 via a traveling transmission (not shown) accommodated in the front transmission case 13, thereby driving the left and right front wheels. 1 is driven. Power input from the engine 4 to the front transmission case 13 is input to the wheel drive case 14 via the traveling transmission and a rotating shaft 15 extending rearward from the front transmission case 13, and the input power is input to the wheel drive case 14. The left and right rear wheels 2 are driven by transmission to the left and right rear wheels 2 via the housed wheel transmission mechanism 16 (see FIG. 2).

[Configuration of wheel drive case]
As shown in FIGS. 2 and 3 , the wheel drive case 14 is supported by the traveling body 3 while extending in the width direction of the traveling body 3 . Specifically, the body frame 10 is provided with left and right main frames 17 extending in the longitudinal direction of the traveling body 3 . The wheel drive case 14 is connected to the supporting portions 18 formed on the left and right main frames 17 by connecting bolts.

As shown in FIG. 2, the rear wheels 2 are rotatably supported at both lateral ends of the wheel drive case 14 via axles 2a. As shown in FIGS. 2 and 3, an input shaft 19 for inputting power transmitted from the traveling transmission via a rotating shaft 15 (see FIG. 1) is provided at an intermediate portion of the wheel drive case 14 in the lateral width direction of the machine body. A wheel transmission mechanism 16 for transmitting the power of the input shaft 19 to the left and right rear wheels 2 is housed in the wheel drive case 14 . As shown in FIGS. 2 and 4, the wheel transmission mechanism 16 includes a gear mechanism 20 housed in an intermediate portion of the wheel drive case 14 in the lateral width direction of the machine body, the gear mechanism 20 and the axle 2a of the left rear wheel 2. and a right interlocking mechanism 16A interlockingly connecting the gear mechanism 20 and the right axle 2a. The gear mechanism 20 is provided with an input shaft 19 interlockingly connected to the rotary shaft 15 (see FIG. 1). The gear mechanism 20 transmits the power transmitted to the input shaft 19 to the left rear wheel 2 via the left interlocking mechanism 16A and the left axle 2a, and transmits the power transmitted to the input shaft 19 to the right interlocking mechanism 16A. and to the right rear wheel 2 via the right axle 2a.

As shown in FIGS. 2 and 4, the wheel drive case 14 is provided with a cylindrical portion 21 that protrudes outward from the middle portion of the wheel drive case 14 in the lateral width direction of the vehicle body. . The cylindrical portion 21 protrudes forward from the wheel drive case 14 . The input shaft 19 is provided in the gear mechanism 20 so as to pass through the cylindrical portion 21 . Between the input shaft 19 and the cylindrical portion 21, two bearings 22 are provided that are fitted on the input shaft 19 and on the cylindrical portion 21. It is rotatably supported by the portion 21 . Two bearings 22 are provided side by side with a gap in the direction along the axis of the input shaft 19 .

As shown in FIG. 4, the gear mechanism 20 includes a bevel gear 20a fixed to the input shaft 19 and a bevel gear 20b fixed to a rotation transmission shaft 23 extending in the vehicle body width direction inside the wheel drive case 14. and have. The bevel gear 20a of the input shaft 19 and the bevel gear 20b of the rotation transmission shaft 23 are in mesh.

As shown in FIG. 2, the left and right interlocking mechanisms 16A include a rotation transmission shaft 23 and a transmission shaft connected to the end of the rotation transmission shaft 23 on the opposite side of the gear mechanism 20 via a steering clutch 24. 25, and a gear interlocking mechanism 26 that reduces the power of the transmission shaft 25 and transmits it to the axle 2a. The rotation transmission shaft 23 of the left interlocking mechanism 16A and the rotation transmission shaft 23 of the right interlocking mechanism 16A are configured by the same rotation transmission shaft.

As shown in FIG. 2, the wheel drive case 14 is provided with an air release portion 27 for releasing air from the inside of the wheel drive case 14 to the outside. The air release portion 27 communicates with the inside of the tubular portion 21 . Specifically, as shown in FIGS. 3 and 4, the air vent portion 27 includes a through hole 28 provided in the peripheral wall portion of the cylindrical portion 21 and a pipe portion 29 communicating with the through hole 28. I have. The communication between the through-hole 28 and the tube portion 29 is achieved by connecting the end portion of the tube portion 29 to the through-hole 28 via a connecting cylinder. The opening 27a of the air vent portion 27 in the tubular portion 21 is formed by the opening of the through hole 28 on the side opposite to the pipe portion side. An air discharge port 27b of the air release portion 27 is formed by an opening of the tube portion 29 on the side opposite to the through-hole side. The opening 27a in the tubular portion 21 of the air vent portion 27 is arranged at a portion of the tubular portion 21 located between the two bearings 22, as shown in FIG. That is, the opening 27a in the tubular portion 21 of the air vent portion 27 is positioned closer to the projecting end of the tubular portion 21 than the first bearing 22a of the two bearings 22, which is closer to the bevel gear 20a of the input shaft 19. It is placed in the part located on the side. Even if the lubricating oil stored in the wheel drive case 14 is blown off by the rotating bevel gears 20a and 20b, it hits the first bearing 22a and is prevented from entering the opening 27a by the first bearing 22a. Of the two bearings 22, the second bearing 22b farther from the bevel gear 20a of the input shaft 19 is located closer to the projecting end side of the cylindrical portion 21 than the opening 27a.

The tube portion 29 is configured to be bendable. Specifically, the tube portion 29 is configured by a bendable hose. As shown in FIG. 3 , a rotating shaft 33 that transmits power from the engine 4 to the seedling planting device 9 passes above the cylindrical portion 21 in the front-rear direction. The air vent portion 27 is arranged in a state in which the rotating shaft 33 is bypassed by bending the pipe portion 29 and the pipe portion 29 is hung on the driving portion frame 34 to be supported.

In the air vent portion 27, the air located inside the wheel drive case 14 is allowed to flow out into the tubular portion 21 through the space between the spheres in the first bearing 22a and flow into the tubular portion 29 through the opening 27a. Air is discharged from the inside of the wheel drive case 14 to the outside by causing the air to flow out from the air outlet 27b through the inside of the portion 29. As shown in FIG. Even if the lubricating oil stored inside the wheel drive case 14 is agitated by the rotating bevel gears 20a and 20b and splattered toward the inside of the tubular portion 21, it hits the first bearing 22a, and the splattered lubricating oil hits the opening 27a. is prevented by the first bearing 22a. The second bearing 22b prevents dust from entering from the outside of the cylindrical portion 21 into the opening 27a by hitting the second bearing 22b.

As shown in FIG. 4 , the cylindrical portion 21 projects from the wheel drive case 14 in an upwardly forward inclined state, and the opening 27 a of the air vent portion 27 is located in the peripheral wall of the cylindrical portion 21 in the wheel drive case 14 . It is arranged at a position higher than the center X in the vertical direction. As shown in FIG. 2, the wheel drive case 14 includes a middle case portion 14A extending in the width direction of the machine body, and a horizontal case portion 14B extending downward from both ends of the middle case portion 14A in the width direction of the machine body. is provided. The vertical center X of the wheel drive case 14 is the vertical center of the middle case portion 14A.

As shown in FIGS. 1 and 4 , the front transmission case 13 and the wheel drive case 14 are provided on the traveling body 3 while being spaced apart in the longitudinal direction of the traveling body 3 . An output shaft 13 a projects from the front transmission case 13 toward the wheel drive case 14 . The output shaft 13 a and an input shaft 19 forming an input shaft of the wheel drive case 14 are interlocked with each other by a rotary shaft 15 . The rotating shaft 15 and the output shaft 13a are connected by a universal joint 15a provided across the front end portion of the rotating shaft 15 and the output shaft 13a. The rotating shaft 15 and the input shaft 19 are connected by a cylindrical connecting member 15b. The interlocking connection between the rotating shaft 15 and the input shaft 19 by the connecting member 15b is achieved by externally fitting a spline shaft portion 15s provided at the rear end portion of the rotating shaft 15 and a spline shaft portion 19s provided at the leading end portion of the input shaft 19. This is achieved by providing the connecting member 15b with a spline hole that engages with the joint member 15b. The connecting member 15b is connected to the input shaft 19 by a connecting pin 15c and is slidable with respect to the rotating shaft 15. As shown in FIG.

The input shaft 19 protrudes from the wheel drive case 14 in an inclined state (forward raised state) positioned higher toward the projecting end side. As compared with the case where the input shaft 19 is projected in a horizontal position, the forward rising angle of the rotary shaft 15 is loose.

As shown in FIGS. 2 and 3, the wheel drive case 14 includes a middle case portion 14A extending in the width direction of the machine body, and horizontal case portions extending downward from both ends of the middle case portion 14A in the width direction of the machine body. 14B and are provided. The left and right horizontal case portions 14B are configured such that the rear wheel 2 is supported under the horizontal case portions 14B.

As shown in FIG. 3 , both the left horizontal case portion 14B and the right horizontal case portion 14B are provided with oil supply ports 30 for supplying lubricating oil to the inside of the wheel drive case 14 . As shown in FIGS. 3 and 5, the fuel filler port 30 is provided above a fuel filler port forming portion 31 projecting upward from the horizontal case portion 14B. A refueling port forming portion 31 is provided with a detachable plug member 32 for opening and closing the refueling port 30 . As shown in FIGS. 3 and 5, the fuel filler port 30 is positioned higher than the center X of the wheel drive case (the center of the middle case portion 14A in the vertical direction of the machine body). The position of the oil surface of the lubricating oil stored in the wheel drive case 14 and the position of the center X of the wheel drive case 14. can be supplied from the oil supply port 30 in an amount that is the same as .

As shown in FIGS. 3 and 5, the left and right fuel filler ports 30 are provided on the rear facing portion of the outer peripheral portion of the horizontal case portion 14B.

[Another embodiment]
(1) In the above-described embodiment, an example in which the pipe portion 29 of the air vent portion 27 is bendable has been shown, but the invention is not limited to this, and the pipe portion 29 may be a metal pipe. In this case, as shown in FIG. 6, the tubular portion 29 includes a tubular portion 29a connected to the tubular portion 21 and a bearing case 36 that supports a bearing 35 fitted on the rotation shaft 33. An air discharge port side pipe portion 29b extending from the case 36 is provided, and the cylinder portion side pipe portion 29a and the air discharge port side pipe portion 29b are configured to communicate with each other via an internal space 36a of the bearing case 36. is possible. The air discharge port 27b of the air release portion 27 can be installed at a position higher than the rotating shaft 33 passing above the cylindrical portion 21 while the pipe portion 29 is formed of a straight metal pipe. The bearing case 36 is supported by the body frame 10 via support members 37 .

(2) In the above-described embodiment, the gear mechanism 20 has the bevel gear 20a of the input shaft 19 and the bevel gear 20b of the rotation transmission shaft 23, but the present invention is not limited to this. For example, it may have three or more gears, or may be a differential mechanism.

(3) In the above-described embodiment, the wheel drive case 14 drivably supports the rear wheels 2, but the wheel drive case 14 may drivably support the front wheels 1. .

(4) In the above-described embodiment, an example in which the horizontal case portion 14B is provided has been shown, but the horizontal case portion 14B may not be provided.

(5) In the above-described embodiment, the second bearing 22b is provided closer to the projecting end of the cylindrical portion 21 than the opening 27a, but the second bearing 22b may not be provided.

(6) In the above-described embodiment, the left and right lateral case portions 14B are provided with the fuel filler ports 30. However, the fuel filler port 30 is provided in at least one of the left lateral case portion 14B and the right lateral case portion 14B. may In addition, although an example in which the fuel filler port 30 is provided on the rear facing portion of the outer peripheral portion of the horizontal case portion 14B has been shown, it may be provided on the front facing portion or upward facing portion of the outer peripheral portion of the horizontal case portion 14B. may

(7) In the above-described embodiment, the cylinder portion 21 is provided with the air release portion 27, but a boss portion protruding high from the middle case portion 14A is provided to release air from the boss portion. may be provided instead of the air vent portion 27.

(8) A state in which the horizontal case portion 14B is configured to be divisible into two split case portions in the front-rear direction, the two split case portions have symmetrical shapes, and both of the two split case portions include a filler opening forming portion. By fabricating the two divided case portions in the above, even if the lateral case portion 14B is connected to either the left or right end of the middle case portion 14A, the outer peripheral portion of the lateral case portion 14B can be connected to either the left or right lateral case portion 14B. A fuel filler port 30 can be provided in the front-facing portion of the body or the rear-facing portion of the body.

The present invention comprises a wheel drive case supported by a traveling machine body in a state extending in the machine body width direction, wheels supported on both side end portions of the wheel drive case, and housed in an intermediate part of the wheel drive case in the machine body width direction. a gear mechanism that transmits power to the wheels on both lateral ends; and a cylindrical portion that protrudes from an intermediate portion of the wheel drive case toward the outside of the wheel drive case and through which the input shaft of the gear mechanism is inserted. Can be applied to work vehicles that have been

2 wheels (rear wheels)
3 traveling machine body 6 driver's seat 14 wheel drive case 19 input shaft 20 gear mechanism 21 tubular portion 22a bearing (first bearing)
22b second bearing 27 air vent 27a opening 29 pipe 30 oil supply port

Claims (6)

a wheel drive case supported by the traveling body in a state extending in the width direction of the body;
wheels supported on both lateral ends of the wheel drive case;
a gear mechanism housed in an intermediate portion of the wheel drive case in the lateral width direction of the vehicle body and transmitting power to the wheels at both lateral ends;
a cylindrical portion protruding from the intermediate portion of the wheel drive case toward the outside of the wheel drive case and through which the input shaft of the gear mechanism is inserted;
a bearing provided between the cylindrical portion and the input shaft in a state of being externally fitted on the input shaft and internally fitted on the cylindrical portion;
an air bleeding portion for bleeding air from the inside of the wheel drive case to the outside,
The air release portion communicates with the inside of the cylindrical portion,
The working vehicle, wherein the opening of the air vent portion in the tubular portion is arranged at a portion of the tubular portion located closer to the projecting end side of the tubular portion than the bearing. A second bearing that fits externally on the input shaft and internally fits on the cylindrical portion is located between the input shaft and a portion of the cylindrical portion located closer to the projecting end than the portion where the opening is located. The work vehicle of Claim 1 provided with. The work vehicle according to claim 1 or 2, wherein the air bleeding portion includes a bendable pipe portion. The wheel drive case includes a middle case portion extending in the width direction of the machine body and including the cylindrical portion; A horizontal case part facing up and down is provided,
A lubrication port for supplying lubricating oil to the inside of the wheel drive case is provided in at least one of the lateral case portions of the both end portions in a state of being positioned higher than the center of the middle case portion in the vertical direction of the fuselage. The work vehicle according to any one of claims 1 to 3. 5. The work vehicle according to claim 4, wherein the fuel filler port is provided in both of the lateral case portions of the both end portions. The wheel drive case is provided at the rear part of the traveling machine body,
The working vehicle according to claim 4 or 5, wherein the fuel filler port is provided in a rear facing portion of the outer peripheral portion of the lateral case portion.

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