JP7189791B2 - running vehicle - Google Patents

Description

The present invention relates to traveling vehicles.

2. Description of the Related Art Conventionally, a traveling vehicle including an engine and a case accommodating a power transmission device for transmitting power from the engine is widely known (see Patent Document 1). The power transmission device is, for example, a forward/reverse switching device that switches forward/backward travel of the traveling vehicle. A power transmission device has a gear and a synchronizer ring that contacts the gear. When the driver shifts gears, the shifter pushes the synchronizer ring toward the gears, and the gears and the synchronizer ring come into contact with each other. Due to the friction generated by this contact, the rotational speeds of the gear and the synchronizer ring match, and the rotation of the shaft is transmitted to the gear via the synchronizer ring.

In general, oil (mission oil) is stored in the case. By immersing at least a portion of the power transmission device (particularly the synchronizer ring) in oil, the oil enters between the gear and the synchronizer ring. The oil reduces the friction between the gear and the synchronizer ring, thereby suppressing wear of the synchronizer ring.

Japanese Patent Application Laid-Open No. 2004-168228

Since the oil in the case heats up when the vehicle is driven, if there is a large amount of oil, damage due to heat increases and costs increase. On the other hand, if the amount of oil is reduced, the synchronizer ring arranged on the upper side in the case is less likely to be soaked in oil, and there is a problem that the synchronizer ring is likely to wear.

Accordingly, it is an object of the present invention to provide a traveling vehicle capable of suppressing wear of a synchronizer ring even when the synchronizer ring is not soaked in oil.

A traveling vehicle according to the present disclosure includes an engine, a case that houses a power transmission device that transmits power from the engine, and a housing space of the case. a supply pipe for supplying oil. The power transmission device has a gear and a synchronizer ring that contacts the gear. The supply pipe includes a tubular body through which the oil flows, a discharge port through which the oil is discharged, and a guide portion that guides the oil discharged from the discharge port to between the gear and the synchronizer ring. and have

Since the oil supplied by the supply pipe is guided between the gear and the synchronizer ring by the guide, the oil is applied to the contact surface of the synchronizer ring that contacts the gear. Therefore, even if the synchronizer ring is not immersed in oil, lubrication between the gear and the synchronizer ring can be maintained, and wear of the synchronizer ring can be suppressed.

According to a preferred aspect, the guide portion is tubular. The guide portion extends from the body portion toward between the gear and the synchronizer ring. The discharge port is provided at an end portion in the extending direction of the guide portion. The guide portion discharges the oil discharged from the outlet facing the gear in the extending direction of the guide portion. Since the guide portion extends between the gear and the synchronizer ring, the discharged oil can be accurately hung between the gear and the synchronizer ring. This helps maintain lubrication between the gear and the synchronizer ring.

According to a preferred aspect, the outlet is arranged above the central axis of the shaft to which the gear is attached. As a result, oil can be applied to the upper side of the gear, which is less likely to be immersed in oil, and lubrication can be maintained between the gear and the synchronizer ring.

According to a preferred aspect, the main body extends so as not to vertically overlap the central axis of the shaft. In a cross section orthogonal to the central axis of the shaft, an imaginary line passing through the center of the discharge port and the central axis of the shaft forms an angle of less than 30 degrees with the extending direction of the guide section. , the extending direction of the guide portion is inclined with respect to the vertical direction. As a result, when the main body and the central axis of the main shaft do not overlap, the oil can be discharged toward the axial center of the gear (that is, the central axis of the shaft). Therefore, it becomes easier for the oil to reach not only the radially outer contact surface between the gear and the synchronizer ring but also the radially inner contact surface between the gear and the synchronizer ring. It becomes easier to lubricate the contact surface between the gear and the synchronizer ring.

According to a preferred aspect, the power transmission device includes a mechanical forward/reverse switching device for switching between forward and reverse travel of the traveling vehicle. The gear is a gear of the forward/reverse switching device. When work using a traveling vehicle (e.g., agricultural work) is performed, since switching between forward and reverse travel occurs frequently, the number of shifts of the forward/reverse switching device is greater than the number of shifts of the transmission. . Therefore, the synchronizer ring that contacts the gears of the forward/reverse switching device wears more easily than the synchronizer ring that contacts the gears of the transmission. Therefore, by guiding oil between the gear of the forward/reverse switching device and the synchronizer ring, wear of the synchronizer ring, which is prone to wear, can be suppressed.

According to a preferred aspect, the forward/reverse switching device has a forward gear and a reverse gear as the gears. The synchronizer ring has a first synchronizer ring that contacts the forward gear and a second synchronizer ring that contacts the reverse gear. The guide portion includes a first guide portion that guides the oil between the forward gear and the first synchronizer ring, and a second guide portion that guides the oil between the reverse gear and the second synchronizer ring. and Since oil is applied to the first synchronizer ring that contacts the forward gear and the second synchronizer ring that contacts the reverse gear, wear of both synchronizer rings can be suppressed.

According to a preferred aspect, the traveling vehicle has a transmission that shifts the power from the engine and transmits the power to drive wheels. The case is positioned between a first accommodation chamber in which the forward/reverse switching device is accommodated, a second accommodation chamber in which the transmission is accommodated, and the second accommodation chamber between the first accommodation chamber and the second accommodation chamber. and a case wall separating the first storage chamber and the second storage chamber. The supply pipe supplies the oil to the first storage chamber. While the oil is being supplied, the oil level in the first storage chamber is higher than before the oil is being supplied. As a result, at least part of the synchronizer ring of the forward/reverse switching device is likely to be soaked in oil. As a result, wear of the synchronizer ring can be further suppressed.

According to a preferred aspect, the case wall is provided with an opening penetrating the first storage chamber and the second storage chamber. The traveling vehicle is arranged in the first storage chamber and has a shaft rotated by power from the engine and a bearing into which the shaft is inserted. The bearing is fixed to the case wall so as to block the opening. Since the bearing is fixed so as to block the opening, the flow rate of oil flowing from the first storage chamber to the second storage chamber through the opening is restricted. As a result, even if the case wall has an opening, oil can easily be stored in the first storage chamber, and at least a portion of the synchronizer ring of the forward/reverse switching device can easily be soaked in oil. As a result, wear of the synchronizer ring can be further suppressed.

According to a preferred aspect, the bearing has an inner ring, an outer ring, rolling elements, and a seal portion closing between the inner ring and the outer ring. This makes it more difficult for oil to pass between the inner ring and the outer ring compared to a bearing that does not have a seal portion, further limiting the flow rate of oil that flows out from the first storage chamber to the second storage chamber. Therefore, oil is easily stored in the first housing chamber, and at least a portion of the synchronizer ring of the forward/reverse switching device is easily soaked in oil. As a result, wear of the synchronizer ring can be further suppressed.

According to a preferred aspect, the seal portion is arranged closer to the first housing chamber than the rolling element. Since the oil is stored closer to the first housing chamber than the seal portion is, compared to the case where the seal portion is farther from the rolling elements, the oil can be easily stored in the first housing chamber, and at least one of the gears of the forward/reverse switching device can be stored. part is easily soaked in oil. As a result, wear of the synchronizer ring can be further suppressed.

According to a preferred aspect, the opening has a first opening to which the bearing without the seal is fixed, and a second opening to which the bearing with the seal is fixed. . The first opening is positioned below the second opening. As a result, it is possible to improve the circulation of oil between the first storage chamber and the second storage chamber on the lower side where oil tends to accumulate.

According to a preferred aspect, the opening further has a third opening to which the bearing without the seal portion is fixed. The third opening is located above the second opening. As a result, the oil flows more easily into the second storage chamber at the third opening than at the second opening. Therefore, it is possible to prevent oil from accumulating in the first storage chamber more than necessary.

According to a preferred aspect, the opening has a fourth opening located above the synchronizer ring. The fourth opening is open without the bearing being fixed. This makes it easier for the oil accumulated above the synchronizer ring to flow into the second storage chamber. Therefore, it is possible to prevent oil from accumulating in the first storage chamber more than necessary.

FIG. 1 is a left side view of a traveling vehicle according to the embodiment. FIG. 2 is a perspective view of the operating device according to the embodiment as viewed from the upper left rear side. FIG. 3 is a rear view of the operating device according to the embodiment. FIG. 4 is a rear view of the operating device according to the embodiment. FIG. 5 is a left side view of the operating device according to the embodiment. FIG. 6 is a left side view of the operating device according to the embodiment. FIG. 7 is an enlarged view of the shuttle lever and guide plate according to the embodiment. FIG. 8 is an enlarged view of the guide plate according to the embodiment. FIG. 9 is an enlarged view of the steering unit according to the embodiment. FIG. 10 is a BB cross-sectional view of FIG. 11 of the case according to the embodiment. 11 is a cross-sectional view of the case according to the embodiment taken along the line AA of FIG. 10. FIG. 12 is a CC cross-sectional view of FIG. 10 of the case according to the embodiment. FIG. 13 is a DD cross-sectional view of FIG. 10 of the case according to the embodiment. FIG. 14 is a perspective view for explaining the bearing according to the embodiment; FIG. 15 is a diagram for explaining the movement of the transmission section; FIG. 16 is a diagram for explaining the movement of the transmission section;

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In addition, in the following description of the drawings, the same or similar reference numerals are given to the same or similar parts. However, it should be noted that the drawings are schematic, and the ratio of each dimension is different from the actual one. Therefore, specific dimensions and the like should be determined with reference to the following description. In addition, portions having different dimensional relationships and ratios may also be included between the drawings. In the present specification and drawings, elements having substantially the same functions and configurations are denoted by the same reference numerals to omit redundant description, and elements that are not directly related to the present invention are omitted from the drawings.

(1) Schematic Configuration of Traveling Vehicle 1 A schematic configuration of the traveling vehicle 1 will be described mainly with reference to FIGS. 1 and 2. FIG. FIG. 1 is a side view of a traveling vehicle according to an embodiment. FIG. 2 is a perspective view of the operating device according to the embodiment as viewed from the upper left rear side. In this embodiment, a tractor is exemplified as the traveling vehicle 1 .

An arrow X shown in the drawing indicates the width direction of the traveling vehicle 1 , an arrow Y indicates the longitudinal direction of the traveling vehicle 1 , and an arrow Z indicates the vertical direction of the traveling vehicle 1 . An arrow X<b>1 indicates the right direction of the traveling vehicle 1 , and an arrow X<b>2 indicates the left direction of the traveling vehicle 1 . An arrow Y1 indicates the forward direction (forward direction) of the traveling vehicle 1, and an arrow Y2 indicates the backward direction (reverse direction) of the traveling vehicle 1. As shown in FIG. An arrow Z1 indicates the upward direction of the traveling vehicle 1, and an arrow Z2 indicates the downward direction of the traveling vehicle 1. As shown in FIG.

A direction from the center to the right or left in the width direction X of the traveling vehicle 1 is referred to as an outward direction, and a direction from the right or left to the center in the width direction X of the traveling vehicle 1 is referred to as an inward direction. Therefore, the center of the traveling vehicle 1 in the width direction X may be referred to as the "vehicle inner side", and the right and left sides of the center in the width direction X may be referred to as the "vehicle outer side".

As shown in FIGS. 1 and 2, a traveling vehicle 1 has a vehicle body 2 that can travel. The vehicle body 2 has an engine 3 , a case 5 , a case cover member 6 and a control device 10 .

Engine 3 is a diesel engine. The engine 3 is located in the front part of the traveling vehicle 1 and is covered with a bonnet. The engine 3 may be an electric motor or a hybrid type having a diesel engine and an electric motor.

Case 5 has a flywheel housing, a clutch housing, and a transmission case. The flywheel housing is connected to the rear part of the engine 3 and accommodates the flywheel. The clutch housing is connected to the rear part of the flywheel housing and accommodates a clutch that intermittently transmits the power of the engine 3 transmitted via the flywheel. The transmission case is connected to the rear portion of the clutch housing.

The case 5 accommodates a power transmission device that transmits power from the engine 3 . The power transmission device may include a forward/reverse switching device 20 and a transmission 30 . In the embodiment, the case 5 accommodates a forward/reverse switching device 20 that switches between forward and reverse travel of the vehicle, and a transmission device 30 that changes the speed of the power from the engine 3 and transmits it to the drive wheels. The forward/reverse switching device 20 has a forward gear 25 and a reverse gear 26 as gears. The case 5 is arranged below the control device 10 in the vertical direction Z. As shown in FIG.

A case cover member 6 covers the upper portion of the case 5 . The case cover member 6 has a body portion 6a that overlaps with the upper portion of the case 5 and side portions 6b that are arranged outside in the width direction X of the body portion 6a when viewed from the top of the vehicle. The upper surface of the body portion 6a is positioned higher than the upper surface of the side portion 6b (see FIG. 2-4).

A driver's foot is placed on the case cover member 6 . The case cover member 6 is arranged on the front side in the front-rear direction Y with respect to the driver's seat 9 . It is arranged on the rear side in the front-rear direction X of the control stand 12 .

As shown in FIG. 1, the traveling vehicle 1 has a traveling device 8 that supports the vehicle body 2 so that it can travel. The traveling device 8 is a wheel-type traveling device having a plurality of front wheels 8A provided on the front portion of the vehicle body 2 and a plurality of rear wheels 8B provided on the rear portion of the vehicle body 2 . The plurality of front wheels 8A includes a left front wheel supported on the left side of the front axle case supported in front of the engine 3 and a right front wheel supported on the right side of the front axle case. The plurality of rear wheels 8B includes a left rear wheel supported on the left side of case 5 (transmission case or the like) and a right rear wheel supported on the right side of case 5 . The traveling device 8 may be a semi-crawler type traveling device (a traveling device having front wheels 8A and a crawler-type traveling mechanism employed in place of the rear wheels 8B).

The front wheel 8A is a steerable wheel that can be steered by moving a cylinder rod of a steering cylinder provided in the front portion of the front axle case. By steering the front wheels 8A, the direction of the vehicle body 2 can be changed (the vehicle body can be steered). The steering cylinder is composed of a hydraulic cylinder.

Of the front wheels 8A and the rear wheels 8B, at least the rear wheels 8B are driving wheels, and power output from the transmission 30 is transmitted to the driving wheels.

A driver's seat 9 on which a driver sits is mounted on the rear portion of the vehicle body 2. - 特許庁A control device 10 partially covered with a control cover 11 is provided in front of the driver's seat 9 .

(2) Details of Pilot Device 10 and Forward/Reverse Switching Device 20 Details of the pilot device 10 and forward/rearward travel switching device 20 will be described with reference mainly to FIGS. 3 to 11 . 3 and 4 are rear views of the operating device according to the embodiment. However, in FIG. 4, some members (case cover member 6, pedal 17, support pipe 18, cover member 124, etc.) are omitted from FIG. 5 and 6 are left side views of the operating device according to the embodiment. 6, some members (case cover member 6, pedal 17, support pipe 18, cover member 124, etc.) are omitted from FIG. FIG. 7 is an enlarged view of the shuttle lever and guide plate according to the embodiment. FIG. 8 is an enlarged view of the guide plate according to the embodiment. FIG. 9 is an enlarged view of the steering unit according to the embodiment. FIG. 10 is a BB cross-sectional view of FIG. 11 of the case according to the embodiment. 11 is a cross-sectional view of the case according to the embodiment taken along the line AA in FIG. 10. FIG. 12 is a CC cross-sectional view of FIG. 10 of the case according to the embodiment. FIG. 13 is a DD cross-sectional view of FIG. 10 of the case according to the embodiment. FIG. 14 is a perspective view for explaining the bearing according to the embodiment; FIG. 15 is a diagram for explaining the movement of the transmission section; FIG. 16 is a diagram for explaining the movement of the transmission section; It should be noted that in each drawing, some members may be omitted as appropriate.

As shown in FIGS. 1-6, the control device 10 has a control platform 12, a shuttle lever 13, a guide plate 14, a transmission section 15, a steering section 16, pedals 17, and a support pipe .

As shown in FIG. 1 , the control platform 12 has a fixed bracket 122 and a cover member 124 .

The fixed bracket 122 is erected on the vehicle body 2 (case 5). The fixed bracket 122 supports the transmission section 15 and the steering section 16 .

As shown in FIG. 3, the fixed bracket 122 has a first side wall 1221 and a second side wall 1222 facing the first side wall. The first side wall 1221 and the second side wall 1222 are arranged outside the transmission portion 15 in the width direction X. As shown in FIG. The first side wall 1221 and the second side wall 1222 are plate-shaped members extending in the up-down direction Z. As shown in FIG.

The first side wall 1221 and the second side wall 1222 are arranged side by side in the width direction X (arranged to face each other in the width direction X). The first side wall 1221 is arranged on the left side of the center of the vehicle body 2 in the width direction X, and the second side wall 1222 is arranged on the right side of the center of the vehicle body 2 in the vehicle width direction.

The first side wall 1221 and the second side wall 1222 are connected by a first connecting member 1223 and a second connecting member 1224 .

A left end portion of the first connecting member 1223 is fixed to the first side wall 1221 , and a right end portion of the first connecting member 1223 is fixed (connected) to the second side wall 1222 . The first connecting member 1223 has a through hole 1223a through which the steering post 164 passes, and the steering controller 166 is fixed.

A left end portion of the second connecting member 1224 is fixed to the first side wall 1221 , and a right end portion of the second connecting member 1224 is fixed (connected) to the second side wall 1222 . The second connecting member 1224 fixes the first side wall 1221 and the second side wall 1222 at the respective front portions of the first side wall 1221 and the second side wall 1222 .

Fixed bracket 122 has a third side wall 1225 that supports oil tank 168 .
A third sidewall 1225 is fixed to the top of the second sidewall 1222 .

Fixed bracket 122 has a fixed plate 1226 . A through hole is formed in the fixed plate 1226 . The transmission portion 15 (specifically, the shuttle shaft 152 and the support tube 153) is inserted into the through hole. The fixed plate 1226 is fixed to the first side wall 1221 .

Cover member 124 covers the rear side of steering controller 166 . Cover member 124 is connected to first side wall 1221 and second side wall 1222 .

The shuttle lever 13 is a member that performs an operation for switching the running direction of the vehicle body 2 . By operating the shuttle lever 13 forward or backward, the operation of the shuttle lever 13 is transmitted to the forward/reverse switching device 20 via the transmission portion 15 . As a result, the running direction (advancing direction) of the vehicle body 2 is switched between the forward direction and the reverse direction.

As shown in FIGS. 3-8, the shuttle lever 13 has a lever body 131 and a grip 132 connected to an upper end portion 131a of the lever body 131. As shown in FIGS.

A guide plate 14 guides the shuttle lever 13 . The guide plate 14 is a plate-like member. The guide plate 14 has a rectangular shape when viewed from above (see FIG. 8). The guide plate 14 extends in the width direction X. As shown in FIG. The guide plate 14 has a guide hole 142 and an insertion hole 144 . The guide hole 142 is a hole into which the shuttle lever 13 (lower end portion 131b of the lever body 131) is inserted, and is a through hole that penetrates the guide plate 14. As shown in FIG. By integrating the guide hole 142 and the insertion hole 144 into one guide plate 14, the space of the control device 10 can be saved.

The guide hole 142 has an arc-shaped portion 142A and a protrusion 142B projecting in the width direction X from the center of the arc portion 142A in the front-rear direction Y when viewed from the top of the guide plate 14 .

The insertion hole 144 is a through hole through which the transmission portion 15 is inserted and passes through the guide plate 14 . By inserting the transmission part 15 into the insertion hole 144, the transmission part 15 can be fixed.
The insertion hole 144 is located inside the guide hole 142 in the width direction X. As shown in FIG.

As shown in FIGS. 3-8, the guide plate 14 extends from the inside to the outside in the width direction X. As shown in FIGS. An end portion 141 in the width direction X of the guide plate 14 is located outside the first side wall 1221 in the width direction X. As shown in FIG. As a result, even if the length in the width direction X from the first side wall 1221 to the second side wall 1222 is reduced in order to increase the space under the driver's feet, the length in the width direction X of the guide plate 14 is secured. be able to. Therefore, the space under the driver's feet can be increased without affecting the operation of the shuttle lever 13. - 特許庁The arc portion 142A may be located outside the first side wall 1221 .

The guide plate 14 is supported by support members 145 . The guide plate 14 is fixed to the support member 145 . As a result, the position of the guide plate 14 is not fixed via the side walls (for example, the first side wall 1221) that constitute the control device 10. As shown in FIG. Therefore, the position of the guide plate 14 can be freely designed without being affected by the position of the first side wall 1221 . A support member 145 also extends from the support 146 to the steering device 10 . Therefore, the guide plate 14 is not fixed via the side walls (for example, the first side wall 1221) that constitute the control device 10. As shown in FIG. Therefore, the guide plate 14 is not configured by a member fixed to the first side wall 1221 and extending in the vertical direction Z. As shown in FIG. Therefore, the position of the guide plate 14 can be freely designed without being affected by the position of the first side wall 1221 .

In general, when an existing guide plate is fixed to the first side wall 1221, the guide plate usually has a first portion extending upward in the vertical direction Z from the first side wall 1221 and a width from the upper end of the first portion. and a second portion extending inward in the direction X. Therefore, the length in the width direction X from the first side wall 1221 to the second side wall 1222 cannot be made smaller than necessary in order to secure the length of the second portion that guides the shuttle lever.

On the other hand, since the guide plate 14 according to the present embodiment is not fixed to the first side wall 1221 , it can extend outward in the width direction X beyond the first side wall 1221 . Therefore, even if the length in the width direction X from the first side wall 1221 to the second side wall 1222 is reduced in order to increase the space under the driver's feet, the length in the width direction X of the guide plate 14 should be secured. can be done.
As a result, the space under the driver's feet can be increased without affecting the operation of the shuttle lever 13. - 特許庁

The support member 145 is fixed to a support body 146 that is located on the front side of the operating device 10 in the longitudinal direction Y. As shown in FIG. A support 146 is located within the bonnet. Support 146 is not fixed to case 5 .

The support member 145 has a first support member 145A to which the guide plate 14 is directly fixed, and a second support member 145B that supports the guide plate 14 via the first support member 145A.

The first support member 145A is a plate-like member. The first support member 145A has an arc-shaped first end 145Ae1 along the steering post 164 on the rear side in the front-rear direction Y, and a second end 145Ae2 extending in the rearward direction Y2 from the first end 145Ae1. (See Figure 8). The first support member 145A may be in contact with the steering post 164 . The left side portion 145AL of the first support member 145A is longer in the front-rear direction Y than the right side portion 145AR. As a result, for example, even if a force in the right direction X1 is applied to the guide plate 14 by operating the shuttle lever 13, the right side portion 145AR (second end portion 145Ae2) hits the steering post 164, so the guide plate 14 moves. can be suppressed. Therefore, the guide plate 14 can be firmly fixed. Further, the outer end portion in the width direction X of the right side portion 145AR extends rearward in the front-rear direction Y. As shown in FIG. Accordingly, even if a force in the left direction X2 is applied to the guide plate 14, the right side portion 145AR hits the steering post 164, so that the movement of the guide plate 14 can be suppressed.

The guide plate 14 is fixed to the first support member 145A on the inside in the width direction X. As shown in FIG. Specifically, the first support member 145A is fixed to the guide plate 14 on the outside in the width direction X with bolts and nuts. Therefore, the guide plate 14 is fixed above the left side portion 145AL of the first support member 145A. The first support member 145A is fixed to the second support member 145B with bolts and nuts at the front portion of the first support member 145A.

The second support member 145B is a member extending in the front-rear direction Y. As shown in FIG. The second support member 145B is fixed to the first support member 145A with bolts and nuts at the rear portion of the second support member 145B. The second support member 145B is fixed to the support 146 by bolts and nuts at the front portion of the second support member 145B.

As shown in FIGS. 4, 6, 15, 16, etc., the transmission portion 15 is a member that transmits the operation of the shuttle lever 13 to the forward/reverse switching device 20. As shown in FIG. In the front-rear direction Y, the transmission portion 15 is located on the front side of the cover member 124 . This makes it possible to increase the space under the driver's feet.

The transmission section 15 has a mounting member 151 , a shuttle shaft 152 , a support cylinder 153 , an interlocking rod 154 , a connecting member 155 , a shuttle arm 156 and an engaging section 157 .

The attachment member 151 is a member attached to the shuttle lever 13 . Specifically, the lever body 131 is fixed to the left end of the mounting member 151 . Specifically, the lever body 131 is fixed to the left end of the mounting member 151 . The mounting member 151 is supported on the shuttle shaft 152 by bolts and nuts. The mounting member 151 (that is, the shuttle lever 13) can swing in the vertical direction Z around the bolt.

The shuttle shaft 152 can be rotated about its axis by the shuttle lever 13 . An upper portion 152A of the shuttle shaft 152 protrudes upward from the support tube 153. As shown in FIG. The upper portion 152A is inserted into the insertion hole 144. As shown in FIG. The upper portion 152A is attached to the mounting member 151 and supports the mounting member 151 .

A lower portion 152B of the shuttle shaft 152 protrudes downward from the support cylinder 153 . The lower portion 152B is bent in the width direction X. An end of the lower portion 152B is connected to an interlocking rod 154. As shown in FIG.

The support tube 153 is arranged vertically so as to extend in the vertical direction Z. As shown in FIG. The support cylinder 153 is positioned between the first side wall 1221 and the second side wall 1222 in the width direction X. As shown in FIG. The support tube 153 is positioned between the second connecting member 1224 and the cover member 124 in the front-rear direction Y. As shown in FIG. The support tube 153 is inserted into a through hole formed in the fixing plate 1226 and fixed via the fixing plate 1226 . Therefore, the support tube 153 is fixed to the fixed bracket 122 .

The interlocking rod 154 is a member extending in the front-back direction Y. As shown in FIG. A front end 154A of the interlocking rod 154 is connected to the shuttle shaft 152 by bolts and nuts. A rear end portion 154B of the interlocking rod 154 is connected to the connecting member 155 by bolts and nuts. Accordingly, the interlocking rod 154 is connected with the shuttle arm 156 via the connecting member 155 .

Connecting member 155 connects interlocking rod 154 and shuttle arm 156 . The inner end of the connecting member 155 is connected to the interlocking rod 154 by bolts and nuts. The outer end of connecting member 155 is directly fixed to shuttle arm 156 .

The shuttle arm 156 extends in the up-down direction Z. As shown in FIG. The shuttle arm 156 has an arm body 156A and an arm tube 156B.

An upper end portion of the arm body 156A is fixed to the connecting member 155. As shown in FIG. Arm body 156A rotates as connection member 155 rotates. A lower end portion of the arm body 156A is fixed to the engaging portion 157 .

The arm body 156A is inserted into the arm tube 156B. The arm tube 156B is not connected to the connection member 155, but is connected to the case 5. As shown in FIG.

The engaging portion 157 is a member that contacts the shift fork 21 . The engaging portion 157 is fixed to the arm body 156A. The shift fork 21 moves along with the movement of the engaging portion 157 . The engaging portion 157 is fixed to the arm body 156A on the inner side in the width direction X, and engages with the shift fork 21 (the third fork portion 213) on the outer side in the width direction X.

The steering unit 16 has a steering handle 162 , a steering post 164 , a steering controller 166 and an oil tank 168 .

The steering handle 162 is a member operated by the driver. The steering handle 162 is a member that operates the steering of the vehicle body 2 and is manually operated by the driver.

A steering post 164 supports a steering handle 162 and a steering controller 166 . A steering shaft (shaft) is inserted into the steering post 164 . The steering post 164 transmits the operation of the steering handle 162 to the steering controller 166 via the steering shaft.

The steering controller 166 controls the steering of the traveling vehicle 1 by operating the steering handle 162 . The steering controller 166 is hydraulic.
A steering controller 166 is a valve that controls a steering cylinder. The steering controller 166 is a rotary valve that is operated by the steering handle 162 to control the flow rate of hydraulic fluid and switch the direction of the hydraulic fluid. In other words, the steering controller 166 is a valve capable of outputting hydraulic fluid for transmitting steering of the steering handle 162 . The steering controller 166 outputs hydraulic fluid corresponding to the amount of operation of the steering handle 162 from a port corresponding to the direction of operation. Hydraulic fluid output from the steering controller 166 is sent to the steering cylinder to move the cylinder rod of the steering cylinder. As a result, the front left wheel and the front right wheel are steered according to the turning operation of the steering handle 162 .

As shown in FIGS. 4, 6 and 9, the steering controller 166 is connected to a plurality of hydraulic hoses (first hose H1-fourth hose H4).

The first hose H<b>1 is a hydraulic hose that supplies the steering controller 166 with hydraulic fluid discharged from a hydraulic pump P installed in the traveling vehicle 1 . A hydraulic pump P is provided in the bonnet. The hydraulic pump P is driven by the power of the engine 3 .

The second hose H2 is a hydraulic hose that supplies (discharges) working oil to a case 5 that stores working oil (mission oil). The second hose H2 has a first hose portion H2A from the steering controller 166 to the oil tank 168, and a second hose portion H2B from the oil tank 168 to the case 5.

The second hose H2 corresponds to a flow path connecting the steering controller 166 and the tank port T. As shown in FIG. Hydraulic oil flows through the second hose H2. Note that the tank port T is the case 5 . More specifically, the tank port T is a first storage chamber 51 (and a second storage chamber 52), which will be described later.

As shown in FIG. 9, the oil tank 168 is arranged in the middle of the second hose H2.
Hydraulic oil is stored in the oil tank 168 while the engine 3 of the traveling vehicle 1 is stopped. Hydraulic oil is stored in the oil tank 168 even when the engine 3 is in operation.

Oil tank 168 is arranged below steering handle 162 . Thereby, the length of the flow path of the second hose portion H2B can be shortened.

The oil tank 168 has an inlet 168A and an outlet 168B. The inflow port 168A is an inlet through which hydraulic oil flows into the oil tank 168 . Outflow port 168B is an outlet through which hydraulic oil flows out from oil tank 168 . The outflow port 168B is arranged at a position higher than the inflow port 168A. As shown in FIG. 9, the outflow port 168B may be arranged inside the oil tank 168 . Specifically, the outflow port 168B may be provided with a cylinder portion 1682 having the outflow port 168B inside the oil tank 168 . In this case, the upper end of the tubular portion 1682 corresponds to the outflow port 168B. Cylindrical portion 1682 extends from lower surface 168L of oil tank 168 toward upper surface 168U. When the hydraulic oil stored in the oil tank 168 exceeds the height of the outflow port 168B, it flows into the second hose H2 from the outflow port 168B by gravity.

The oil tank 168 has a space 168s in which hydraulic oil is stored. In the oil tank 168, the lower surface 168L of the space 168s is arranged at a position higher than the inlet H2Ain through which hydraulic oil flows from the steering controller 166 to the flow path (second hose H2).

The provision of the oil tank 168 allows the steering controller 166 to maintain the hydraulic pressure.

The third hose H3 and fourth hose H4 are connected to the steering cylinder. The third hose H3 is a left turn hydraulic hose. The hydraulic fluid supplied through the third hose H3 operates the steering cylinder so as to steer the front left wheel and the front right wheel to the left. The fourth hose H4 is a hydraulic hose for turning to the right. The hydraulic oil supplied through the fourth hose H4 operates the steering cylinder so as to steer the front left wheel and the front right wheel to the left.

The pedals 17 are operated by the feet of the driver. As shown in FIGS. 2, 3 and 5, the pedals 17 are arranged outside the control stand 12 in the width direction X. As shown in FIGS. The pedals 17 have a clutch pedal 171 , a first brake pedal 172 and a second brake pedal 173 .

A clutch pedal 171 is a pedal for operating a clutch. The clutch pedal 171 has a pedal plate portion 171a and a pedal body 171b. One end of the pedal plate portion 171 a is connected to the support pipe 18 . The other end of the pedal plate portion 171a is connected to the pedal body 171b. The pedal main body 171b is a portion that is stepped on by the sole of the driver's foot when operated by the driver.

The first brake pedal 172 and the second brake pedal 173 are pedals that operate brakes that brake the traveling device 8 . The first brake pedal 172 has a pedal plate portion 172a and a pedal body 172b. One end of the pedal plate portion 172 a is connected to the support pipe 18 . The other end of the pedal plate portion 12a is connected to the pedal body 172b. The second brake pedal 173 has a configuration similar to that of the first brake pedal 172 . The pedal body 172b is a portion that is stepped on by the sole of the driver's foot when operated by the driver.

The clutch pedal 171 is arranged on the left side of the control platform 12 . The first brake pedal 172 and the second brake pedal 173 are arranged on the right side of the control platform 12 . The second brake pedal 173 is arranged on the right side of the first brake pedal 172 .

The support pipe 18 is a pipe that supports the pedal 17 . The support pipe 18 is fixed (connected) to the control platform 12 . The support pipe 18 is a pipe extending in the width direction X. As shown in FIG.

As shown in FIGS. 10 and 11, the case 5 includes a first accommodation chamber 51 in which the forward/reverse switching device 20 is accommodated, a second accommodation chamber 52 in which the transmission 30 is accommodated, and a second accommodation chamber 52 in which the clutch is accommodated. 3 containing chambers 53 .

The first storage chamber 51 is arranged between the second storage chamber 52 and the third storage chamber 53 in the front-rear direction Y. As shown in FIG. The first storage chamber 51 is arranged below the operating device 10 . Therefore, the forward/reverse switching device 20 is arranged below the control device 10 .

The case 5 has a case upper portion 51A, a case lower portion 51B, a case left portion 51C, a case right portion 51D, a first case wall portion 55, and a second case wall portion .

The case upper portion 51A is positioned above the first storage chamber 51 . Therefore, the case upper portion 51A is a portion arranged above the space forming the first storage chamber 51 . The case lower portion 51B is positioned below the first storage chamber 51 . The case left portion 51</b>C is positioned on the left side of the first storage chamber 51 . The case right portion 51D is located on the right side of the first storage chamber 51 .

The case 5 has a through hole 51Aa that penetrates the case upper portion 51A and into which the transmission portion 15 is inserted. Specifically, an arm body 156A is inserted into the through hole 51Aa. Compared to the case of inserting the transmission part 15 from the side surface of the case 5, it is not necessary to bring the transmission part 15 to the side surface of the case 5.例文帳に追加Therefore, the space under the feet can be widened. Moreover, it is not necessary to provide a long cover in the width direction X under the feet of the driver in order to cover the transmission portion 15 . Therefore, the space under the driver's feet can be expanded. In addition, since the distance of the transmission portion 15 from the shuttle lever 13 to the forward/reverse switching device 20 can be shortened, the shift feeling can be improved. Since the length of the transmission portion 15 is shortened to improve the shift feel, instead of increasing the rigidity of the transmission portion 15 to improve the shift feel, the cost can be reduced.

As shown in FIG. 5, the pedal 17 (for example, the clutch pedal 171) is arranged at a position closer to the driver's seat 9 in the longitudinal direction Y than the through hole 51Aa. Specifically, the rear end of the pedal main body 171b is arranged in the front-rear direction Y at a position closer than the through hole 51Aa. In addition, the rear end of the pedal body 171b is arranged at a position closer in the front-rear direction Y than the transmitting portion 15 itself. When the pedals 17 are operated, the pedals 17 are less likely to hit the transmission portion 15 inserted into the through hole 51Aa, and the space under the driver's feet can be increased. The pedal 17 may be arranged at a position closer to the driver's seat than the through hole 51Aa and the transmission portion 15 when the driver does not operate the pedal 17 (normal state). The through-hole 51</b>Aa and the transmission portion 15 may be arranged at a position closer to the driver's seat than the pedal 17 when the pedal is depressed by the driver's operation.

As shown in FIGS. 2 and 5, the front end portion of the case cover member 6 in the front-rear direction Y may be positioned on the rear side in the front-rear direction Y of the through hole 51Aa (and the transmission portion 15). More specifically, the front end portion of the main body portion 6a of the case cover member 6 may be located on the rear side of the through hole 51Aa (and the transmission portion 15) in the front-rear direction Y. Therefore, it can be seen that the case cover member 6 does not cover the transmission portion 15 . It is not necessary to dispose the transmission part 15 between the case 5 and the case cover member 6 in order to extend the transmission part 15 to the side surface of the case 5 . Therefore, the case cover member can be arranged closer to the case 5 (that is, further down) in the vertical direction Z, so that the space under the driver's feet can be increased. The front end portion of the side portion 6b of the case cover member 6 may or may not be positioned behind the through hole 51Aa (and the transmission portion 15) in the front-rear direction Y.

As shown in FIGS. 3 and 4, the through hole 51Aa and the transmission portion 15 may be located inside the first side wall 1221 and the second side wall 1222 in the width direction X. As shown in FIGS. As a result, it is possible to prevent the driver's foot from hitting the transmission unit 15 . Further, the transmission portion 15 may be located inside the side portion 6b of the case cover member 6 in the width direction X. As shown in FIG. The transmission portion 15 may be located inside in the width direction X of the outer end portion of the main body portion 6 a of the case cover member 6 . The pedal 17 (for example, the clutch pedal 171 ) may be positioned inside in the width direction X of the main body portion 6 a of the case cover member 6 . With such a configuration, the distance in the width direction X between the pedal 17 (for example, the clutch pedal 171) and the transmission portion 15 can be secured.

The first case wall portion 55 is positioned between the first storage chamber 51 and the second storage chamber 52 . The first case wall portion 55 separates the first storage chamber 51 and the second storage chamber 52 . The second case wall portion 56 is positioned between the first storage chamber 51 and the third storage chamber 53 . The second case wall portion 56 separates the first storage chamber 51 and the third storage chamber 53 .

The forward/reverse switching device 20 is accommodated in the first accommodation chamber 51 . The forward/reverse switching device 20 has a shift fork 21 , a main shaft 22 , a shifter 23 , a fork rod 24 , a forward gear 25 , a reverse gear 26 , a coupling 27 and a synchronizer ring 28 .

The shift fork 21 is movable via the transmission section 15 by operating the shuttle lever. Shift fork 21 is attached to fork rod 24 . The shift fork 21 has a pair of first fork portions 211 ( 211 U, 211 L), a second fork portion 212 and a third fork portion 213 .

The first fork portion 211 is connected to the shifter 23 . As a result, the shifter 23 moves together with the shift fork 21 (first fork portion 211).

The pair of first fork portions 211 has an upper fork portion 211U arranged on the upper side and a lower fork portion 211L arranged on the lower side. A pair of first fork portions 211 extend from the second fork portion 212 . Specifically, upper fork portion 211U extends upward from second fork portion 212 . The lower fork portion 211L extends inward in the width direction X from the second fork portion 212 .

The second fork portion 212 exists between the pair of first fork portions 211 . A through hole into which the fork rod 24 is inserted is formed in the second fork portion 212 .

The third fork portion 213 is engaged with the transmission portion 15 . The third fork portion 213 is connected to the upper fork portion 211U of the pair of first fork portions 211 . Specifically, the third fork portion 213 is connected to the upper end portion of the upper fork portion 211U. Since the third fork portion 213 engaged with the transmission portion 15 is arranged on the upper side, the length of the transmission portion 15 can be shortened. As a result, deterioration of shift feeling can be suppressed.

A shifter 23 , a forward gear 25 , a reverse gear 26 , a coupling 27 and a synchronizer ring 28 are attached to the main shaft 22 . That is, the forward gear 25 , reverse gear 26 , coupling 27 and synchronizer ring 28 are inserted into the main shaft 22 . A central axis (rotational axis) 22c of the main shaft 22 is closer to the case upper portion 51A than to the case lower portion 51B. As a result, the distance from the transmission portion 15 inserted into the case 5 to the forward/reverse switching device 20 can be shortened.

A synchronizer ring 28 is for synchronizing the rotation of the gears. The synchronizer ring 28 has a first synchronizer ring 281 that contacts the forward gear 25 and a second synchronizer ring 282 that contacts the reverse gear 26 . A shifter 23 and a coupling 27 are arranged between the first synchronizer ring 281 and the second synchronizer ring 282 .

Shifter 23 is movable along main shaft 22 between forward gear 25 and reverse gear 26 . The shifter 23 changes the connection (engagement) between the forward gear 25 and the reverse gear 26 . Specifically, as shown in FIG. 12 , a coupling 27 is arranged radially inside the shifter 23 . When the shifter 23 begins to move in one direction (eg forward direction Y1), the coupling 27 presses the first synchronizer ring 281 against the forward gear 25 . Due to the frictional force generated in forward gear 25 , the rotation of coupling 27 , which rotates integrally with main shaft 22 , begins to be transmitted to synchronizer ring 28 and forward gear 25 . Forward gear 25 meshes with a gear attached to a shaft different from main shaft 22 . The rotation of the gear rotates the shaft, which is designed to rotate the driving wheels so that the traveling vehicle 1 moves forward.

Similarly, when shifter 23 begins to move in the other direction (eg, rearward direction Y2), coupling 27 forces second synchronizer ring 282 against reverse gear 26 . Rotation of the coupling 27 begins to be transmitted to the synchronizer ring 28 and the reverse gear 26 due to the frictional force generated in the reverse gear 26 . It meshes with a back gear attached to a shaft different from the main shaft 22. - 特許庁The rotation of the reverse gear rotates the shaft to rotate the driving wheels so that the traveling vehicle 1 moves backward.

Note that the synchronizer ring 28 may be pushed toward the forward gear 25 or the reverse gear 26 by a synchronizer key arranged between the coupling 27 and the shifter 23 .

The transmission 30 has a main transmission section and an auxiliary transmission section. The main transmission section changes and outputs (transforms) the rotation input from the propulsion shaft. The subtransmission portion changes the rotation input from the main transmission portion and outputs it (changes speed).

As shown in FIGS. 10 to 13 , the traveling vehicle 1 has a supply pipe 60 that supplies oil (working oil) from the outside of the case 5 to the inside of the case 5 . The supply pipe 60 is arranged in the housing space (first housing chamber 51 ) of the case 5 . The supply pipe 60 supplies oil to the first storage chamber 51 . In the embodiment, the supply pipe 60 is a pipe through which the oil that has flowed through the second hose H2 passes. More specifically, the oil that has flowed through the second hose portion H2B flows through the supply pipe 60 . Oil (working oil) discharged from the hydraulic device (specifically, the steering controller 166 ) is supplied (discharged) into the case 5 .

The supply pipe 60 has a body portion 62 , a discharge port 64 and a guide portion 66 . The body portion 62 is a tubular member through which oil flows. The body portion 62 may be a circular tube. In this embodiment, the body portion 62 extends parallel to the central axis (rotational axis) 22c of the main shaft 22 . Accordingly, the body portion 62 extends from the first case wall portion 55 along the front-rear direction Y (the front direction Y1). As shown in FIG. 10, therefore, the body portion 62 extends so as not to overlap the central axis 22c of the main shaft 22 in the vertical direction Z. As shown in FIG. Specifically, the body portion 62 is arranged closer to the second hose H2 than the central axis 22c of the main shaft 22 is. The distance from the second hose H2 to the supply pipe 60 is shortened, and the oil can be quickly applied to the gear.

Oil is discharged from the discharge port 64 . The discharge port 64 may be provided in the guide portion 66 . The discharge port 64 is arranged above the main shaft 22 . As a result, oil can be applied to the upper side of the gear, which is less likely to be immersed in oil, and lubrication between the gear and the synchronizer ring 28 can be maintained.

The guide portion 66 guides the oil discharged from the discharge port 64 between the gear and the synchronizer ring 28 . As a result, oil is applied to the contact surface of the synchronizer ring 28 that contacts the gear. Therefore, even when the synchronizer ring 28 is not immersed in oil, lubrication between the gear and the synchronizer ring 28 can be maintained, and wear of the synchronizer ring 28 can be suppressed.

The guide portion 66 may be tubular. The guide portion 66 may be a nozzle. A guide portion 66 extends from the body portion 62 toward between the gear and the synchronizer ring 28 . A discharge port 64 is provided at an end portion in the extending direction of the guide portion 66 . This allows the drained oil to be accurately hung between the gear and the synchronizer ring 28 . This helps maintain lubrication between the gears and the synchronizer ring 28 .

In the embodiment, the extending direction of the guide portion 66 (vertical direction Z in FIG. 12) is orthogonal to the extending direction of the main body portion 62 (front-to-rear direction Y in FIG. 12). Therefore, the guide portion 66 extends perpendicular to the central axis 22c of the main shaft 22. As shown in FIG. In a cross section perpendicular to the central axis 22c of the main shaft 22 (that is, a cross section along the width direction X and the vertical direction Z (see FIG. 10)), the center of the discharge port 64 and the central axis 22c of the main shaft 22 are aligned. The extending direction of the guide portion 66 is inclined with respect to the vertical direction Z so that the angle formed by the virtual line passing through and the extending direction of the guide portion 66 is less than 30 degrees. As a result, when the main body portion 62 and the central axis 22c of the main shaft 22 do not overlap in the vertical direction Z, the oil can be discharged toward the axis of the gear (that is, the central axis of the main shaft 22). Therefore, it becomes easier for the oil to reach not only the radially outer contact surface between the gear and the synchronizer ring 28 but also the radially inner contact surface between the gear and the synchronizer ring 28 . It becomes easier to lubricate the contact surface between the gear and the synchronizer ring 28 . In addition, in FIG. 10, since the virtual line and the extending direction of the guide portion 66 match, the angle is 0 degree. It should be noted that the guide portion 66 may extend upward from the axis of the gear, or may extend downward from the axis of the gear, taking into account how oil is applied. .

The outlet 64 is desirably located near the synchronizer ring 28 (and the gear) in order to apply a large amount of oil to the synchronizer ring 28 . For example, the distance from the outlet 64 to the synchronizer ring 28 is preferably shorter than the distance from the synchronizer ring 28 to the central axis 22c of the main shaft 22. It should be noted that the guide portion 66 can be separated from the synchronizer ring 28 (and the gear) to the extent that the supply pipe 60 does not hit the synchronizer ring 28 (or the gear) due to the swinging of the supply pipe 60 caused by the driving of the traveling vehicle 1 . preferable.

In this embodiment, the guide portion 66 has a first guide portion 661 and a second guide portion 662 . The first guide portion 661 guides oil between the forward gear 25 and the first synchronizer ring 281 . The first guide portion 661 extends from the body portion 62 toward the forward gear 25 . A first discharge port 641 facing between the forward gear 25 and the first synchronizer ring 281 is provided at an end portion in the extending direction of the first guide portion 661 . The second guide portion 662 guides oil between the reverse gear 26 and the second synchronizer ring 282 . The second guide portion 662 extends from the body portion 62 toward between the reverse gear 26 and the second synchronizer ring 282 . A second discharge port 642 facing between the reverse gear 26 and the second synchronizer ring 282 is provided at an end portion in the extending direction of the second guide portion 662 .

The first guide part 661 is arranged upstream of the downstream end of the supply pipe 60 . The downstream end of supply tube 60 is sealed. The first guide portion 661 is arranged downstream of the second guide portion 662 .

As shown in FIG. 13 , the first case wall portion 55 is provided with an opening 550 extending through the first storage chamber 51 and the second storage chamber 52 below the supply pipe 60 . The opening 550 may have a first opening 551 , a second opening 552 , a third opening 553 and a fourth opening 554 . The first opening 551 is arranged on the lowermost side than the other openings. The second opening 552 is arranged above the first opening 551 . The third opening 553 is arranged above the second opening 552 . The fourth opening 554 is arranged above the third opening 553 . Further, as shown in FIG. 13, the fourth opening 554 is arranged above the synchronizer ring 28 (upper end of the synchronizer ring 28).

The traveling vehicle 1 has a shaft 70 and bearings 58 . The shaft 70 is arranged in the first housing chamber 51 and is rotated by power from the engine 3 . A shaft 70 is inserted in the bearing 58 . The bearing 58 is fixed to the first case wall portion 55 so as to close the opening 550 .

In an embodiment, as shown in FIG. 13, the shaft 70 has a first shaft 71, a second shaft 72, and the main shaft 22 described above. A gear is attached to each shaft. Also, the bearing 58 has a first bearing 581, a second bearing 582 (second bearing 582A, second bearing 582B), and a third bearing 583 (third bearing 583A, third bearing 583B). The first bearing 581 is fixed to the first case wall portion 55 so as to block the first opening portion 551 . Similarly, the second bearing 582 is fixed to the first case wall 55 so as to close the second opening 552 , and the third bearing 583 is fixed to the first case wall so as to close the third opening 553 . 55. The first shaft 71 is inserted in the first bearing 581 , the second shaft 72 is inserted in the second bearing 582 , and the main shaft 22 is inserted in the third bearing 583 . Note that the bearing 58 is not fixed to the fourth opening 554 .

As shown in FIG. 14, the bearing 58 has an inner ring 58I, an outer ring 58O and rolling elements 58R. A shaft 70 is inserted inside the inner ring 58I. The rolling elements 58R are rollers or balls. The rolling element 58R is arranged between the inner ring 58I and the outer ring 58O. The bearing 58 may have a retainer that positions the rolling elements 58R.

As shown in FIGS. 13 and 14B, the second bearing 582A may have an inner ring 582I, an outer ring 582O, rolling elements 582R, and a seal portion 582S. The seal portion 582S closes the space between the inner ring 582I and the outer ring 582O. The seal portion 582S is arranged closer to the first housing chamber 51 than the rolling element 582R. The seal portion 582S is not arranged closer to the second housing chamber 52 than the rolling element 582R. Therefore, the second bearing 582A has the seal portion 582S only on one side. Note that the first bearing 581, the second bearing 582B, and the third bearing 583 do not have seal portions.

10, 11, and 13, the oil level is S1 while the engine is stopped, and the oil level is S2 while the engine is running. Oil in case 5 circulates between the hydraulic device (steering controller 166 ) and case 5 .

Specifically, when the engine 3 is rotating due to the operation of the engine 3, the oil stored in the second storage chamber 52 is supplied to the hydraulic equipment. As a result, oil is supplied from the second housing chamber 52 to the hydraulic equipment. The amount of oil in the second storage chamber 52 is slightly decreased, and the oil level of the oil in the second storage chamber 52 is slightly lowered. Since the capacity of the second housing chamber 52 for containing oil is larger than the capacity of the first housing chamber 51, the difference in oil level fluctuation between when the engine 3 is rotating and when it is stopped is small.

By supplying oil from the second storage chamber 52 to the hydraulic equipment, oil is supplied (discharged) from the hydraulic equipment to the first storage chamber 51 . When the engine 3 is rotating, oil (working oil) from the steering controller 166 is supplied to the first housing chamber 51 through the discharge port 64 . As a result, in the first accommodation chamber 51, the oil level rises to S2 while the engine 3 is rotating. While the oil is being supplied, the oil level in the first storage chamber 51 is higher than before the oil is being supplied. In addition, oil preferentially accumulates in the first storage chamber 51 . Therefore, even if the central axis 22c of the main shaft 22 is close to the case upper portion 51A, the synchronizer ring 28 attached to the main shaft 22 is likely to be soaked in the oil accumulated in the first housing chamber 51, so the amount of oil used can be reduced. can be reduced.

It should be noted that the higher the rotational speed of the engine 3, the greater the amount of oil supplied to the first storage chamber 51, and the faster the oil level in the first storage chamber 51 rises. On the other hand, as the rotation speed of the engine 3 decreases, the amount of oil supplied to the first storage chamber 51 decreases, and the oil level in the first storage chamber 51 rises slowly.

Oil is supplied to the first storage chamber 51 through a supply pipe 60 . Here, a case is assumed in which the supply pipe 60 does not have the guide portion 66 and the main body portion 62 is directly provided with the discharge port 64 . Oil flowing through the body portion 62 of the supply pipe 60 has a velocity component along the body portion 62 . Therefore, since the oil discharged from the discharge port 64 of the body portion 62 has a velocity component in the extending direction of the body portion 62 (forward direction Y1 in FIG. 12), ). Here, the viscosity of the oil inside the case 5 which has been heated to a high temperature by driving the traveling vehicle 1 is lower than that of the oil at a low temperature. Therefore, the speed of the oil flowing through the supply pipe 60 increases, and the oil is discharged further forward. In particular, in the case of two outlets 64, the pressure in the pipe is higher at the upstream outlet 64 compared to the downstream outlet 64, so the oil velocity is higher and the oil is discharged further forward. Cheap. Thus, even if the gear and the synchronizer ring 28 are arranged so that the oil discharge trajectory passes between the gear and the synchronizer ring 28, the discharge trajectory changes depending on whether the oil temperature is high or low. , the contact surface of the synchronizer ring 28 may not be covered with oil. The synchronizer ring 28 attached to the main shaft 22 is easily damaged because it is not immersed in oil until the oil level rises to S2. Further, even if the oil level rises to S2, only a portion of the synchronizer ring 28 is immersed in oil, so it is preferable to apply oil to the portion that is not immersed in oil.

According to the above, the guide portion 66 guides the oil discharged from the outlet 64 to the gear. Accordingly, since the oil supplied by the supply pipe 60 is guided between the gear and the synchronizer ring 28 by the guide portion 66, the contact surface of the synchronizer ring 28 that contacts the gear is covered with oil. Therefore, even when the synchronizer ring 28 is not immersed in oil, lubrication between the gear and the synchronizer ring 28 can be maintained, and wear of the synchronizer ring 28 can be suppressed. Moreover, not only the synchronizer ring 28 but also gear wear can be suppressed.

A discharge port 64 is provided at an end portion of the cylindrical guide portion 66 in the extending direction (the front-rear direction Y in FIGS. 11 and 12). Since the guide portion 66 extends between the gear and the synchronizer ring 28 , the oil that has flowed inside the cylindrical guide portion 66 is discharged toward between the gear and the synchronizer ring 28 . be. This allows the oil to be applied accurately between the gear and the synchronizer ring 28 .

Further, the gear to which oil is guided by the guide portion 66 is the gear of the forward/reverse switching device 20 . When a work using the traveling vehicle 1 (for example, farming work) is performed, the number of shifts of the forward/reverse switching device 20 is larger than the number of shifts of the transmission 30, because switching between forward and reverse travel occurs frequently. , become many. Therefore, the synchronizer ring 28 that contacts the gears of the forward/reverse switching device 20 wears more easily than the synchronizer ring 28 that contacts the gears of the transmission 30 . Therefore, by guiding oil between the gear of the forward/reverse switching device 20 and the synchronizer ring 28, wear of the synchronizer ring 28, which is easily worn, can be suppressed.

Even if the gears of the transmission 30 are not immersed in oil, the splashing of the oil stored in the second storage chamber 52 sufficiently lubricates the synchronizer ring of the transmission 30 .

The guide portion 66 includes a first guide portion 661 that guides oil between the forward gear 25 and the first synchronizer ring 281, and a second guide portion that guides oil between the reverse gear 26 and the second synchronizer ring 282. 662. Since oil is applied to the first synchronizer ring 281 contacting the forward gear 25 and the second synchronizer ring 282 contacting the reverse gear 26, wear of both synchronizer rings 28 can be suppressed.

On the other hand, since the opening 550 is provided in the first case wall portion 55 , oil flows from the first storage chamber 51 to the second storage chamber 52 through the opening 550 . As a result, when the engine 3 is rotating, the oil level in the second storage chamber 52 is lowered to S2, but the oil does not run out from the second storage chamber 52 .

Here, since the bearing 58 is fixed so as to close the opening 550 , the flow rate of oil flowing from the first storage chamber 51 to the second storage chamber 52 through the opening 550 is restricted. As a result, even if the opening 550 is provided in the first case wall portion 55, oil can easily be stored in the first housing chamber 51, and at least a portion of the synchronizer ring 28 can easily be soaked in oil.

Also, the second bearing 582A has a seal portion 582S. This makes it more difficult for oil to pass between the inner ring 582I and the outer ring 582O compared to the bearing 58 (for example, the first bearing 581) that does not have the seal portion 58S. The flow of oil to 52 is further restricted. Therefore, oil is easily stored in the first housing chamber 51, and at least a portion of the synchronizer ring 28 is easily soaked in oil. In particular, when the traveling vehicle 1 is driven and the temperature rises, the viscosity of the oil decreases, so that the oil easily flows from the first storage chamber 51 to the second storage chamber 52 through the opening 550 . Therefore, by restricting the oil flow rate by the seal portion 582S, the oil level in the first storage chamber 51 can be maintained high even when the oil is at a high temperature.

Further, when the rotation speed of the engine 3 is low, the amount of oil supplied to the first storage chamber 51 is small, so the speed at which the oil level rises in the first storage chamber 51 slows down. Therefore, by restricting the flow rate of the oil flowing from the first storage chamber 51 to the second storage chamber 52 by the bearing 58, the oil can be easily stored in the first storage chamber 51 even when the engine speed is low. Become. As a result, at least a portion of the synchronizer ring 28 is likely to be immersed in oil.

Note that even if the bearing 58 has the seal portion 58S, the oil passes through the gap between the shaft 70 and the bearing 58 and the gap between the first case wall portion 55 and the bearing 58 to open. It flows out from the first storage chamber 51 to the second storage chamber 52 through the portion 550 . If the seal portion 58S does not seal the space between the inner ring 58I and the outer ring 58O, the oil flows through the bearing 58 into the second housing chamber 52, although the flow rate is small.

Also, the seal portion 582S of the second bearing 582 is arranged closer to the first housing chamber 51 than the rolling element 582R. Since the oil is stored closer to the first storage chamber 51 than the seal portion 582S is, compared to the case where the seal portion 582S is farther than the rolling element 582R, it becomes easier to store the oil in the first storage chamber 51 (the oil surface rises faster). easier to climb). Therefore, at least part of the synchronizer ring 28 is likely to be soaked in oil.

The first opening 551 to which the first bearing 581 without the seal portion 58S is fixed is located below the second opening 552 to which the second bearing 582 with the seal portion 582S is fixed. As a result, the circulation of oil between the first storage chamber 51 and the second storage chamber 52 can be improved on the lower side where oil tends to accumulate. As a result, it is possible to prevent continued use of oil whose performance has deteriorated (for example, high-temperature oil) in either the first storage chamber 51 or the second storage chamber 52 . On the other hand, by making it difficult for the oil to flow out from the second opening 552 , which tends to be higher than the oil surface of the second storage chamber 52 , the oil can be easily stored in the first storage chamber 51 . .

A third bearing 583 that does not have a seal portion 58S is fixed to the third opening 553. As shown in FIG. The third opening 553 is located above the second opening 552 . As a result, oil flows more easily into the second storage chamber 52 at the third opening 553 than at the second opening 552 . Therefore, it is possible to prevent oil from accumulating in the first storage chamber 51 more than necessary.

Also, the fourth opening 554 is arranged above the synchronizer ring 28 . The fourth opening 554 is open without the bearing 58 being fixed. As a result, since the bearing 58 is not fixed, the oil accumulated above the synchronizer ring 28 flows more easily into the second housing chamber 52 compared to the third opening 553 . Since the oil accumulated above the synchronizer ring 28 does not contribute to the lubrication of the synchronizer ring 28, it is possible to further prevent oil from accumulating in the first housing chamber 51 more than necessary.

When the engine 3 is stopped, oil is not supplied from the second housing chamber 52 to the hydraulic equipment. Therefore, oil is not supplied from the hydraulic equipment to the first storage chamber 51 . While the engine 3 is stopped, oil flows out from the first storage chamber 51 to the second storage chamber 52 through the second opening 552 and the third opening 553 . As a result, the oil level in the first storage chamber 51 is lowered to S1.

(3) Movement of Transmission Unit 15 Movement of the transmission unit 15 will be described mainly with reference to FIGS. 15 and 16. FIG.

In FIG. 15, shuttle lever 13 is in a neutral position. At this neutral position, the shuttle lever 13 (lower end portion 131b of the lever body 131) is positioned on the protrusion 142B of the guide hole 142. As shown in FIG. In this case, the shuttle lever 13 cannot be operated back and forth. Further, when the shuttle lever 13 is at the neutral position, the forward/reverse switching device 20 is in the power-disconnected state (that is, the shifter 23 is not connected to either the forward gear 25 or the reverse gear 26), No power is output from the transmission 30 to the traveling device 8 .

The shuttle lever 13 can swing upward against the biasing force of the spring at the neutral position. When the shuttle lever 13 is swung upward at the neutral position, the shuttle lever 13 moves from the protrusion 142B of the guide hole 142 to the arc portion 142A. When the shuttle lever 13 is swung upward, the shuttle lever 13 can move within the arc portion 142A of the guide hole 142. As shown in FIG. Therefore, the shuttle lever 13 can swing back and forth.

When the shuttle lever 13 is moved in the direction F1 (rear direction Y2) along the arc portion 142A, the shuttle lever 13 is moved from the neutral position to the forward position. When the shuttle lever 13 is in the forward position, the forward/reverse switching device 20 is in a state of transmitting forward power, and the traveling direction of the vehicle body 2 is switched to the forward direction.

Specifically, when shuttle lever 13 is operated in direction F1, upper portion 152A of shuttle shaft 152 rotates in direction F2, and lower portion 152B of shuttle shaft 152 moves in direction F3. As a result, the interlocking rod 154 moves in the F4 direction (backward direction Y2), and the connecting member 155 and the shuttle arm 156 rotate in the F5 and F6 directions, respectively. Rotation of the shuttle arm 156 causes the engaging portion 157 to move in the F7 direction, and the shift fork 21 moves along the main shaft 22 in the F8 direction (forward direction Y1). As a result, the shifter 23 is connected to the forward gear 25, and the forward/reverse switching device 20 is switched to transmit forward power.

On the other hand, when the shuttle lever 13 is moved along the arc portion 142A in the direction R1 (rear direction Y2), the shuttle lever 13 is moved from the neutral position to the reverse position. When the shuttle lever 13 is in the reverse position, the forward/reverse switching device 20 is in a state of transmitting reverse driving power, and the running direction of the vehicle body 2 is switched to the reverse direction.

Specifically, when the shuttle lever 13 is operated in the R1 direction, the upper portion 152A of the shuttle shaft 152 rotates in the R2 direction, and the lower portion 152B of the shuttle shaft 152 moves in the R3 direction. As a result, the interlocking rod 154 moves in the R4 direction (rear direction Y2), and the connecting member 155 and the shuttle arm 156 rotate in the R5 and R6 directions, respectively. Rotation of the shuttle arm 156 causes the engaging portion 157 to move in the R7 direction, and the shift fork 21 moves along the main shaft 22 in the R8 direction (rear direction Y2). As a result, the shifter 23 is connected to the reverse gear 26, and the forward/reverse switching device 20 is switched to transmit reverse power.

(4) Other Embodiments Although the present invention has been described in detail using the above-described embodiments, it should be apparent to those skilled in the art that the present invention is not limited to the embodiments described herein. is. The present invention can be implemented with modifications and variations without departing from the spirit and scope of the invention defined by the claims. Accordingly, the descriptions herein are for the purpose of illustration and description, and are not intended to have any limiting meaning with respect to the present invention.

For example, in the above description, the guide portion 66 may be provided by bending the downstream end portion of the supply pipe 60 toward the gear. As a result, the number of man-hours for processing the supply pipe 60 can be reduced compared to the case where the first guide portion 661 and the first discharge port 641 are formed.

In the above description, the guide portion 66 may extend vertically downward from the body portion 62 . Since the oil is discharged vertically downward by the guide portion 66, it is difficult for the discharged oil to have a horizontal velocity component. Therefore, the discharged oil can easily reach the gear facing the discharge port without being shifted in the horizontal direction (for example, the forward direction in FIG. 12). Lubrication between the gears and the synchronizer ring 28 can be maintained because the oil can be applied to a targeted location regardless of the temperature of the oil.

Although the supply pipe 60 has two discharge ports 64 in the above, it is not limited to this. The supply tube 60 may have one outlet 64 . A supply tube 60 may direct oil from a single outlet 64 between multiple gears and multiple synchronizer rings 28 . Also, the supply tube 60 may have three or more outlets 64 . The supply pipe 60 may have a number of guide portions 66 corresponding to the number of discharge ports 64 . The supply tube 60 may have a number of outlets 64 and guides 66 corresponding to the number of synchronizer rings 28 to be oiled.

In the above description, only the second bearing 582A has the seal portion 582S, but the present invention is not limited to this. At least one of the other bearings 58 (first bearing 581, second bearing 582B, and third bearing 583) may have a seal portion 58S. Also, the second bearing 582A may not have the seal portion 582S.

Also, in the second bearing 582A, the seal portion 582S is arranged closer to the first housing chamber 51 than the rolling element 582R, but this is not the only option. The seal portion 582S may be arranged not closer to the first storage chamber 51 than the rolling element 582R, and may be located closer to the second storage chamber 52 than the rolling element 582R. Alternatively, the seal portion 582S may be arranged on both the first storage chamber 51 side and the second storage chamber 52 side with respect to the rolling element 582R. As a result, the flow rate of oil flowing out from the first storage chamber 51 to the second storage chamber 52 through the second opening 552 can be further restricted.

In the above description, oil is applied from the supply pipe 60 between the gear of the forward/reverse switching device and the synchronizer ring 28, but this is not the only option. Oil may be applied between the synchronizer ring 28 and a gear other than the gear of the forward/reverse switching device 20 (for example, the gear of the transmission 30).

For example, the oil tank 168 is arranged below the steering controller 166, but this is not the only option. For example, the oil tank 168 may be provided within the hood.

In the above description, the steering controller 166 is used as an example of the hydraulic equipment, but it may be other hydraulic equipment or may include other hydraulic equipment.

1: Running vehicle 2: Car body 3: Engine 5: Case 6: Case cover member 8: Traveling device 9: Driver's seat 10: Control device 11: Control cover 12: Control platform 13: Shuttle lever 14: Guide plate 15: Transmission part 16: Steering unit 17: Pedal 18: Support pipe 20: Forward/reverse switching device 22: Main shaft 25: Forward gear 26: Reverse gear 30: Transmission device 51: First accommodation chamber 51Aa: Through hole 52: Second accommodation chamber 53 : Third housing chamber 55 : First case wall 56 : Second case wall 58 : Bearing 60 : Supply pipe 62 : Body 64 : Discharge port 66 : Guide 70 : Shaft 550 : Opening 551 : First opening Part 552 : Second opening 553 : Third opening 554 : Fourth opening 581 : First bearing 582 : Second bearing 583 : Third bearing 661 : First guide part 662 : Second guide part

Claims (11)

a moving vehicle,
engine and
a case housing a power transmission device that transmits power from an engine;
a supply pipe disposed in the housing space of the case and supplying oil from the outside of the case to the inside of the case;
a mechanical forward/reverse switching device for switching between forward and reverse travel of the traveling vehicle as the power transmission device;
a transmission device for transmitting the power from the engine to the driving wheels ,
The power transmission device has a gear and a synchronizer ring in contact with the gear,
The supply pipe is
a tubular main body through which the oil flows;
a discharge port through which the oil is discharged;
a guide portion that guides the oil discharged from the discharge port to between the gear and the synchronizer ring ;
the gear is a gear of the forward/reverse switching device;
Said case is
a first accommodation chamber in which the forward/reverse switching device is accommodated;
a second accommodation chamber in which the transmission is accommodated;
a case wall portion positioned between the first storage chamber and the second storage chamber and separating the first storage chamber and the second storage chamber;
The supply pipe supplies the oil to the first storage chamber,
A traveling vehicle in which, while the oil is being supplied, the oil level in the first housing chamber is higher than before the oil is being supplied . The guide portion is cylindrical,
The guide portion extends from the body portion toward between the gear and the synchronizer ring,
2. The traveling vehicle according to claim 1, wherein the discharge port is provided at an end portion in the extending direction of the guide portion. 3. The traveling vehicle according to claim 1, wherein the outlet is arranged above a central axis of a shaft to which the gear is attached. The main body extends so as not to overlap the central axis of the shaft in the vertical direction,
In a cross section orthogonal to the central axis of the shaft, an imaginary line passing through the center of the discharge port and the central axis of the shaft forms an angle of less than 30 degrees with the extending direction of the guide section. 4. The traveling vehicle according to claim 3, wherein the extending direction of the guide portion is inclined with respect to the vertical direction. The forward/reverse switching device has a forward gear and a reverse gear as the gears,
The synchronizer ring has a first synchronizer ring that contacts the forward gear and a second synchronizer ring that contacts the reverse gear,
The guide portion includes a first guide portion that guides the oil between the forward gear and the first synchronizer ring, and a second guide portion that guides the oil between the reverse gear and the second synchronizer ring. The traveling vehicle according to claim 1 , comprising: The case wall is provided with an opening penetrating the first storage chamber and the second storage chamber,
a shaft arranged in the first storage chamber and rotated by power from the engine;
a bearing into which the shaft is inserted;
The traveling vehicle according to claim 1 , wherein the bearing is fixed to the case wall so as to close the opening. 7. The traveling vehicle according to claim 6 , wherein the bearing has an inner ring, an outer ring, rolling elements, and a seal portion closing a space between the inner ring and the outer ring. 8. The traveling vehicle according to claim 7 , wherein the seal portion is arranged closer to the first housing chamber than the rolling element. The opening is
a first opening to which the bearing without the seal is fixed;
a second opening to which the bearing having the seal is fixed;
The traveling vehicle according to claim 7 or 8 , wherein the first opening is positioned below the second opening. The opening further has a third opening to which the bearing without the seal is fixed,
The traveling vehicle according to claim 9 , wherein the third opening is located above the second opening. The opening further has a fourth opening arranged above the synchronizer ring,
11. The traveling vehicle according to claim 10 , wherein the fourth opening is open without the bearing being fixed.

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