JP7777293B2 - combine - Google Patents

Description

The present invention relates to a combine harvester equipped with a continuously variable transmission that increases or decreases the traveling speed of the traveling gear.

In conventional combine harvesters, a known technology is to operate a speed change lever on the control panel to increase or decrease the engine output rotation speed, and to increase or decrease the output rotation speed of a continuously variable transmission installed on the transmission path between the engine and the traveling gear, thereby increasing or decreasing the traveling gear speed. (See Patent Document 1.)

Japanese Patent Application Laid-Open No. 2022-176677

However, with the technology in Patent Document 1, if a heavy load is placed on the engine and the engine output rotation continues to slow down, there is a risk of the engine being damaged due to overheating, or the continuously variable transmission being damaged due to a decrease in circulating hydraulic oil.

The objective of the present invention is to provide a combine that can reduce the traveling speed of the traveling device when the engine output rotation speed decreases, thereby preventing damage to the engine and continuously variable transmission.

The present invention, which has solved the above problems, is as follows.
That is, the invention of claim 1 is a combine harvester in which a traveling device (2) is provided below a machine frame (1) on which an engine (E) is mounted, a reaping device (3) is provided in front of the machine frame (1), a threshing device (4) is provided behind the reaping device (3) on the left side, and a control unit (5) is provided behind the reaping device (3) on the right side,
A continuously variable transmission (30) for increasing/decreasing the output rotation of the engine (E) and switching the rotation direction is provided downstream of the transmission path of the engine (E), a traveling device (2) is provided downstream of the transmission path of the continuously variable transmission (30), a speed change lever (16) for increasing/decreasing the output rotation of the engine (E) and the output rotation of the continuously variable transmission (30) is provided in the operating section (5), and a controller (50) of the operating section (5) is configured to control the engine (E) when a preset time has elapsed in which the load factor of the engine (E) is 100% or more and the output rotation of the engine (E) is 100% or more. When the speed of the engine (E) is reduced to a predetermined first set output speed or more below the rated speed, the output rotation of the engine (E) is increased or decreased and the forward motor (42) and reverse motor (43) of the continuously variable transmission (30) are driven to reduce the running speed of the traveling device (2) to a predetermined first set running speed , regardless of the operating position of the speed change lever (16), and the set time is set to a time for leveling out fluctuations in the load on the engine (E) caused by fluctuations in the amount of straw transported to the threshing device (4) .

The invention described in claim 2 is a combine according to claim 1, which stops increasing or decreasing the output rotation of the engine (E) when the output rotation of the engine (E) is decelerated to a first set output rotation or greater while being less than the rated rotation of the engine (E).

The invention described in claim 3 is the combine according to claim 1 or 2, in which the set time is set to 3 seconds .

The invention described in claim 4 is a combine according to claim 1, in which, when the output rotation of the engine (E) is slowed down below a first set output rotation to a preset second set output rotation or more, the output rotation of the engine (E) is increased or decreased and the forward motor (42) and reverse motor (43) of the continuously variable transmission (30) are driven to slow down the running speed of the running device (2) to a preset second set running speed that is slower than the first set running speed.

The invention described in claim 5 is a combine described in claim 4, in which when the output rotation of the engine (E) is decelerated below a first set output rotation to above a second set output rotation, the increase/decrease of the output rotation of the engine ( E ) is stopped.

The invention described in claim 6 is a combine described in claim 4 , in which the increase/decrease of the output rotation of the engine (E) is stopped when the output rotation of the engine (E) is decelerated to less than a second set output rotation.

According to the invention of claim 1, a continuously variable transmission (30) for increasing/decreasing the output rotation of the engine (E) and switching the rotation direction is provided downstream of the transmission path of the engine (E), a traveling device (2) is provided downstream of the transmission path of the continuously variable transmission (30), a speed change lever (16) for increasing/decreasing the output rotation of the engine (E) and the output rotation of the continuously variable transmission (30) is provided in the operating section (5), and a controller (50) of the operating section (5) controls the operation of the speed change lever (16) to increase/decrease the output rotation of the engine (E) and the output rotation of the continuously variable transmission (30) when a preset time has elapsed in which the load factor of the engine (E) is 100% or more and the output rotation of the engine (E) is decelerated to a preset first set output rotation or more below the rated rotation of the engine (E). Regardless of the operating position, the output rotation of the engine (E) is increased or decreased, and the forward motor (42) and reverse motor (43) of the continuously variable transmission (30) are driven to reduce the traveling speed of the traveling device (2) to a preset first set traveling speed , and the set time is set to a time for leveling out fluctuations in the load on the engine (E) caused by fluctuations in the amount of straw transported to the threshing device (4). Therefore , when the output rotation of the engine (E) falls below the rated output rotation, the traveling speed of the traveling device (2) is reduced to the first set traveling speed, thereby reducing the load on the engine (E) and the continuously variable transmission (30) and preventing damage to the engine (E) and the continuously variable transmission (30). In addition, the traveling speed of the traveling device (2) is reduced to the first set traveling speed, thereby preventing pulsation occurring in the traveling speed.

According to the invention of claim 2, in addition to the effects of the invention of claim 1, if the output rotation of the engine (E) is decelerated to a first set output rotation or greater while being less than the rated rotation of the engine (E), the increase/decrease of the output rotation of the engine (E) is stopped, thereby quickly reducing the load on the engine (E) and further preventing damage to the engine (E).

According to the invention of claim 3, in addition to the effects of the invention of claim 1 or 2, since the set time is set to 3 seconds , fluctuations in the load applied to the engine (E) can be more evened out.

According to the invention of claim 4 , in addition to the effects of the invention of claim 1, when the output rotation of the engine (E) is decelerated below the first set output rotation to a preset second set output rotation or more, the output rotation of the engine (E) is increased or decreased and the forward motor (42) and the reverse motor (43) of the continuously variable transmission (30) are driven to decelerate the traveling speed of the traveling device (2) to a preset second set traveling speed that is slower than the first set traveling speed. Therefore, when the output rotation of the engine (E) becomes less than the first set output rotation, the traveling speed of the traveling device (2) is decelerated to the second set traveling speed, thereby further reducing the load applied to the engine (E) and the continuously variable transmission (30) and further suppressing damage to the engine (E) and the continuously variable transmission (30).

According to the invention of claim 5 , in addition to the effect of the invention of claim 4 , when the output rotation of the engine (E) is decelerated below the first set output rotation to equal to or greater than the second set output rotation, the increase/decrease of the output rotation of the engine (E) is stopped, thereby quickly reducing the load on the engine (E) and further suppressing damage to the engine (E).

According to the invention described in claim 5 , in addition to the effect of the invention described in claim 4 , when the output rotation of the engine (E) is decelerated to less than the second set output rotation, the increase/decrease of the output rotation of the engine (E) is stopped. Therefore, when the output rotation of the engine (E) becomes less than the second set output rotation, the load applied to the engine (E) is quickly reduced, thereby further suppressing damage to the engine (E).

FIG. FIG. FIG. 1 is a transmission diagram of the engine output rotation. FIG. FIG. 2 is an explanatory diagram of a continuously variable transmission. This is a connection diagram between the main controller and the engine controller. This is a method for controlling the engine output rotation. This is a theoretical control map for the engine. This is an actual control map of the engine. FIG. 2 is a perspective view of a support device that supports the reaping device. FIG. 10 is a perspective view of the left support device of the support device moved to a storage position. FIG. 10 is a perspective view of the left support device of the support device moved to an open position. FIG. 10 is a front view of the left support device of the support device with a cover attached to the front part thereof. FIG. 10 is a left side view of the support device with a cover attached to the front of the left support device. FIG. 10 is a left side view of the support device with the hook of the right support device engaged with the pin. FIG. 10 is a left side view of the right support device of the support device with the hook and pin disengaged.

As shown in Figures 1 to 3, a traveling device 2 consisting of a pair of left and right crawlers that travels on the soil surface is provided on the underside of the combine's body frame 1, and a reaping device 3 that harvests stalks in the field is provided on the front side of the body frame 1. Additionally, a threshing device 4 that threshes and sorts the stalks harvested by the reaping device 3 is provided on the rear left side of the reaping device 3, and a control unit 5 on which an operator rides is provided on the rear right side of the reaping device 3.

Below the control unit 5 is an engine room 6 housing the engine E, and behind the control unit 5 is a grain tank 7 for storing grain that has been threshed and sorted by the threshing device 4. The grain stored in the grain tank 7 is discharged to the outside by a discharge auger (not shown) connected to the grain tank 7.

A front panel 10 is provided in front of the cockpit of the control unit 5, and a side panel 15 is provided to the left of the cockpit.

A touch panel monitor 11 is provided on the left side of the front panel 10, which displays the traveling speed of the traveling device 2 and the engine's E output rotations, while an operating lever 12 is provided on the right side, which controls the rotation of the traveling device 2 and the raising and lowering of the harvesting device 3. The tilt position of the operating lever 12 is measured by an angle sensor, such as a potentiometer, attached to the bottom of the operating lever 12.

A main speed change lever (referred to as "speed change lever" in the claims) 16 is provided at the front of the side panel 15 to operate the hydraulic continuously variable transmission 30, which increases/decreases the output rotation of the engine E and switches its direction of rotation. A sub-speed change lever 17 is provided behind the main speed change lever 16 to operate the transmission 31, which increases/decreases the output rotation of the continuously variable transmission 30.

Also, to the right of the main speed change lever 16 is an accelerator lever 18 that increases or decreases the output rotation of the engine E via the engine controller 60 without going through the machine controller (referred to as "controller" in the claims) 50, and behind the sub-speed change lever 17 is a reaper/thresh lever 19 that operates the connection and disconnection of the reaping clutch 32 and threshing clutch 33.

As shown in Figure 4, the output rotation of engine E is transmitted to continuously variable transmission 30 provided on transmission path A. The output rotation of engine E transmitted to the input shaft of continuously variable transmission 30 is accelerated or decelerated and the direction of rotation is switched within continuously variable transmission 30, and then output to the output shaft of continuously variable transmission 30.

The output rotation of the continuously variable transmission 30 is transmitted to the transmission 31 and the harvesting device 3. The output rotation of the continuously variable transmission 30 transmitted to the input shaft of the transmission 31 is accelerated or decelerated by multiple gears within the transmission 31 before being output to the output shaft of the transmission 31, and the output rotation of the transmission 31 is transmitted to the traveling device 2. In addition, a harvesting clutch 32 is provided between the output shaft of the continuously variable transmission 30 and the input shaft of the harvesting device 3.

The output rotation of engine E is transmitted to threshing device 4, which is provided on transmission path B. In addition, a threshing clutch 33 is provided between the output shaft of engine E and the input shaft of threshing device 4.

As shown in Figure 5, when the main speed change lever 16 is operated to the neutral position, the output rotation of the continuously variable transmission 30 becomes zero. When the main speed change lever 16 is operated from the neutral position to the forward tilt position, the rotation direction of the output rotation of the continuously variable transmission 30 becomes forward, the same as the rotation direction of the output rotation of the engine E. Increasing the tilt angle of the forward tilt position increases the output rotation of the engine E and the output rotation of the continuously variable transmission 30, while decreasing the tilt angle of the forward tilt position decreases the output rotation of the engine E and the output rotation of the continuously variable transmission 30. The increase or decrease in the output rotation of the engine E is controlled by the machine controller 50 and the engine controller 60 via the wireless circuit 53.

Furthermore, when the main speed change lever 16 is operated from the neutral position to the rear tilt position, the rotation direction of the output rotation of the continuously variable transmission 30 becomes opposite to the rotation direction of the output rotation of the engine E, and when the tilt angle of the rear tilt position is increased, the output rotation of the engine E and the output rotation of the continuously variable transmission 30 increase, and when the tilt angle of the rear tilt position is decreased, the output rotation of the engine E and the output rotation of the continuously variable transmission 30 decrease.

When the sub-speed change lever 17 is operated to the neutral position, the output rotation of the transmission 31 does not increase or decrease. When the sub-speed change lever 17 is operated from the neutral position to the forward tilt position, the output rotation of the transmission 31 increases, and when the sub-speed change lever 17 is operated from the neutral position to the rearward tilt position, the output rotation of the transmission 31 decreases.

When the accelerator lever 18 is operated to the forward tilt position, the output rotation of the engine E increases, and when the accelerator lever 18 is operated to the rearward tilt position, the output rotation of the engine E decreases. This allows the accelerator lever 18 to be operated to increase or decrease the output rotation of the engine E, thereby increasing or decreasing the rotation speed of the threshing drum, etc. of the threshing device 4, thereby enabling efficient threshing and sorting processes.

When the cutting/threshing lever 19 is operated to a forward tilt position, the cutting clutch 32 and threshing clutch 33 are disengaged, and the cutting device 3 and threshing device 4 are stopped. When the cutting/threshing lever 19 is operated to a rearward tilt position, the cutting clutch 32 and threshing clutch 33 are engaged, and the output rotation of the engine E is transmitted to the cutting device 3 and threshing device 4, driving the cutting device 3 and threshing device 4. When the cutting/threshing lever 19 is operated to a neutral position, the cutting clutch 32 is engaged and the threshing clutch 33 is disengaged, driving the cutting device 3 and threshing device 4.

The tilt position of the main shift lever 16 is measured by an angle sensor 16S such as a potentiometer attached to the bottom of the main shift lever 16, the tilt position of the sub-shift lever 17 is measured by an angle sensor attached to the bottom of the sub-shift lever 17, the tilt position of the accelerator lever 18 is measured by an angle sensor 18S attached to the bottom of the accelerator lever 18, and the tilt position of the mowing lever 19 is measured by an angle sensor 19S attached to the bottom of the mowing lever 19.

As shown in Figure 6, the base of a fan-shaped operating tool 41 is supported on the trunnion shaft 40 of the continuously variable transmission 30. A gear 42A supported on the output shaft of the forward motor 42 and a gear 43A supported on the output shaft of the reverse motor 43 are engaged with gears formed on the outer periphery of the operating tool 41. This allows the forward motor 42 and reverse motor 43 to be driven based on the attitude of the main speed change lever 16, i.e., the measurement value of the angle sensor 16S, to rotate the trunnion shaft 40 of the continuously variable transmission 30, thereby increasing or decreasing the output rotation of the continuously variable transmission 30 and switching the rotation direction.

Also, instead of the configuration shown in Figure 6, one side of an arm extending radially can be supported on the trunnion shaft 40 of the continuously variable transmission 30, and the other side of the arm can be connected to a forward cylinder driven by a forward solenoid and a reverse cylinder driven by a reverse solenoid, thereby rotating the trunnion shaft 40 of the continuously variable transmission 30.

As shown in Figure 7, the device controller 50 is made up of a processing unit 51 consisting of a CPU, etc., and a memory unit 52 consisting of ROM, RAM, a hard disk drive, flash memory, etc.

When the output rotation of engine E is decelerated to a predetermined first or second set output rotation due to the load applied to engine E, processing unit 51 performs processing such as decelerating the traveling speed of traveling device 2 to the predetermined first or second set traveling speed regardless of the tilted position of main shift lever 16.

The memory unit 52 stores the first and second preset output rotation speeds of the engine E, the first and second preset running speeds of the traveling device 2, etc.

Connected to the machine controller 50 via a specified input interface circuit are a monitor 11 that sets the first and second set output rotation speeds, an angle sensor 16S that measures the tilt position of the main speed change lever 16, an angle sensor 19S that measures the tilt position of the mowing lever 19, and other devices.

The machine controller 50 is connected to the reaping clutch 32, threshing clutch 33, and the forward motor 42 and reverse motor 43 that rotate the trunnion shaft 40 of the continuously variable transmission 30 via a specified output interface circuit.

Connected to the engine controller 60 via a specified interface circuit are an angle sensor 18S that measures the tilt position of the accelerator lever 18, a speed sensor 61 that measures the output rotation of the engine E, i.e., the output rotation of the output shaft of the engine E, an opening sensor 62 that measures the opening state of the throttle valve that supplies combustion air to the cylinders of the engine E, and a fuel sensor 63 that measures the amount of fuel injected into the cylinders of the engine E.

The machine controller 50 and engine controller 60 are also connected via a wireless circuit 53. As a result, input information from the angle sensor 16S and other sensors input to the machine controller 50 is sent to the engine controller 60, and operating the main shift lever 16 from the neutral position to the forward tilt position allows the output rotation of the engine E to be increased or decreased. Furthermore, input information from the speed sensor 61 input to the engine controller 60 is sent to the machine controller 50, allowing the output rotation of the engine E to be controlled based on input such as the output rotation of the engine E.

As shown in FIG. 8, in step S1, the processing unit 51 of the machine controller 50 determines whether the main shift lever 16 has been operated to a position that starts control of the output rotation, etc. of the engine E. For example, if it determines that the main shift lever 16 has been operated to the neutral position, which is the control start position, the process proceeds to step S2, but if it determines that the main shift lever 16 has not been operated to the control start position, step S1 is repeated. The operating position of the main shift lever 16 is measured by the angle sensor 16S.

In step S2, the processing unit 51 drives the throttle valve of engine E via the wireless circuit 53 and engine controller 60 to increase the output rotation of engine E to the rated output rotation, and then proceeds to step S3. The rated output rotation of engine E installed in the combine harvester of this embodiment is 2600 rpm, and the green zone is 2000 to 2600 rpm.

In step S3, the processing unit 51 determines whether the load factor of engine E is equal to or greater than a preset load factor. If the load factor of engine E is equal to or greater than the preset load factor, the process proceeds to step S4; if the load factor of engine E is less than the preset load factor, the process returns to step S2. The load factor of engine E is a ratio calculated by dividing the amount of fuel injected into engine E by the amount of fuel injected into engine E at rated output rotation, and the amount of fuel injected into engine E is measured by the fuel sensor 63. In addition, in this embodiment, the set load factor of engine E is set to 100%.

In step S4, the processing unit 51 determines whether the load rate of engine E has remained at 100% or above for a predetermined period of time. If the load rate of engine E has remained at 100% or above for a predetermined period of time, the process proceeds to step S5. If the load rate of engine E has not remained at 100% or above for a predetermined period of time, the process returns to step S3. This makes it possible to level out fluctuations in the load on engine E due to fluctuations in the amount of straw transported to the threshing device 4, thereby preventing the control system from becoming unstable. The elapsed time is measured by a timer in the machine controller 50. In this embodiment, the set time is set to 3 seconds.

In step S5, the processing unit 51 determines whether the output rotation of engine E has decelerated from the rated output rotation. If it determines that the output rotation of engine E has decelerated from the rated output rotation, the process proceeds to step S6, and if it determines that the output rotation of engine E is maintaining the rated output rotation, the process returns to step S2. The output rotation of engine E is measured by the speed sensor 61.

In step S6, the processing unit 51 determines whether the output rotation of engine E has been decelerated to a first set output rotation or more below the rated output rotation. If the output rotation of engine E has been decelerated to a first set output rotation or more below the rated output rotation, the process proceeds to step S7. If the output rotation of engine E has been decelerated to less than the first set output rotation, the process proceeds to step S8. In this embodiment, the first set output rotation is set to 2500 rpm, which is 100 rpm slower than the rated output rotation and falls within the green zone.

In step S7, the processing unit 51 controls the speed of the traveling device 2 to increase or decrease the output rotational speed of the engine E via the radio circuit 53 and the engine controller 60, and drives the forward motor 42 and reverse motor 43 to reduce the traveling speed to the first set traveling speed, and then returns to step S1. This reduces the load on the engine E, preventing the engine E from overheating, and suppresses damage to the continuously variable transmission 30 due to a reduction in the output rotational speed of the engine E. In this embodiment, the first set traveling speed is set to a traveling speed that is 10% slower than the traveling speed of the traveling device 2 corresponding to the operating position of the main shift lever 16. For example, if the traveling speed of the traveling device 2 corresponding to the operating position of the main shift lever 16 is 40 km/h, the first set traveling speed is set to 36 km/h. The processing unit 51 can also stop the control of increasing or decreasing the output rotational speed of the engine E via the radio circuit 53 and the engine controller 60, and drive the forward motor 42 and reverse motor 43 to reduce the traveling speed of the traveling device 2 to the first set traveling speed.

In step S8, the processing unit 51 determines whether the output rotation of engine E has been decelerated to equal to or greater than the second set output rotation but less than the first set output rotation. If the output rotation of engine E has been decelerated to equal to or greater than the second set output rotation but less than the first set output rotation, the process proceeds to step S9. If the output rotation of engine E has been decelerated to less than the second set output rotation, the process proceeds to step S10. In this embodiment, the second set output rotation is set to 2400 rpm, which is 200 rpm slower than the rated output rotation and falls within the green zone.

In step S9, the processing unit 51 controls the speed of the traveling device 2 to decrease or increase the output rotational speed of the engine E via the radio circuit 53 and the engine controller 60, and drives the forward motor 42 and reverse motor 43 to decrease the traveling speed to the second set traveling speed, and then returns to step S1. This reduces the load on the engine E, better preventing the engine E from overheating, and further suppresses damage to the continuously variable transmission 30 due to a decrease in the output rotational speed of the engine E. In this embodiment, the second set traveling speed is set to a traveling speed that is 20% slower than the traveling speed of the traveling device 2 corresponding to the operating position of the main shift lever 16. For example, if the traveling speed of the traveling device 2 corresponding to the operating position of the main shift lever 16 is 40 km/h, the second set traveling speed is set to 32 km/h. The processing unit 51 can also stop the control of increasing or decreasing the output rotational speed of the engine E via the radio circuit 53 and the engine controller 60, and drive the forward motor 42 and reverse motor 43 to decrease the traveling speed of the traveling device 2 to the first set traveling speed.

In step S10, the processing unit 51 stops controlling the increase/decrease of the output rotation of the engine E via the radio circuit 53 and the engine controller 60, and returns to step S1. The processing unit 51 continues to drive the forward motor 42 and reverse motor 43 to decelerate the traveling speed of the traveling device 2. This removes the excessive load on the engine E, preventing damage to the engine E.

Figure 9 shows the theoretical control map of the output rotation of engine E and the control ratio of the forward motor 42 and reverse motor 43 that rotate the trunnion shaft 40 of the continuously variable transmission 30, i.e., the control ratio of the continuously variable transmission 30, while Figure 10 shows the actual control map of the output rotation of engine E and the control ratio of the continuously variable transmission 30. The rated output rotation of engine E installed in the combine harvester of this embodiment is 2600 rpm, and the green zone is 2000 to 2600 rpm.

The horizontal axis of the theoretical control map and the actual control map represents the output rotation speed [rpm] of the engine E, and the vertical axis represents the control ratio [%] of the continuously variable transmission 30.

As shown in Figure 9, the theoretical control map is formed by the first control line C1 to the fifth control line C5. Note that in this specification, the first control line C1 to the fifth control line C5 are collectively referred to as control lines C.

The first control line C1 sets the control ratio of the continuously variable transmission 30 to 40% when the output rotation of engine E is 1000 to 1400 rpm, the second control line C2 sets the control ratio of the continuously variable transmission 30 to 40 to 70% when the output rotation of engine E is 1400 to 1700 rpm, the third control line C3 sets the control ratio of the continuously variable transmission 30 to 70% when the output rotation of engine E is 1700 to 2000 rpm, the fourth control line C4 sets the control ratio of the continuously variable transmission 30 to 70 to 100% when the output rotation of engine E is 2000 to 2300 rpm, and the fifth control line C5 sets the control ratio of the continuously variable transmission 30 to 100% when the output rotation of engine E is 2300 to 2600 rpm. However, if a load greater than a predetermined level is applied to engine E near the lower limit speed of the green zone of engine E, there is a risk that the control of the control ratio of the continuously variable transmission 30 may become unstable due to a large drop in output rotation speed, etc.

As shown in Figure 10, the actual control map is formed by the first control line D1 to the third control line D3. Note that in this specification, the first control line D1 to the third control line D3 are collectively referred to as control lines D.

The first control line D1 sets the control ratio of the continuously variable transmission 30 to 40% when the engine E output rotation speed is 1000-1400 rpm. The second control line D2 sets the control ratio of the continuously variable transmission 30 to 40-100% when the engine E output rotation speed is 1400-2000 rpm. The third control line D3 sets the control ratio of the continuously variable transmission 30 to 100% when the engine E output rotation speed is 2000-2600 rpm. This prevents the control ratio of the continuously variable transmission 30 from becoming unstable due to a large drop in output rotation speed that occurs when a load greater than a predetermined level is applied to the engine E near the lower limit speed of the green zone of the engine E. Control can also be simplified by reducing the number of control lines.

To clarify the technical significance of the control ratio of the continuously variable transmission 30, the following describes an example in which, when the main shift lever 16 is operated from the neutral position to the maximum forward tilt position, the output rotation of the engine E within the continuously variable transmission 30 is increased to 120% of the output rotation of the engine E, i.e., the speed increase rate within the continuously variable transmission 30 is 20%.

The third control line D3 indicates that when the load on engine E is less than a predetermined value and the output rotation speed of engine E is between 2000 rpm and 2600 rpm, the control ratio is 100% and the speed increase rate within continuously variable transmission 30 is 20%. In other words, the output rotation speed of engine E, which is 2000-2600 rpm transmitted to continuously variable transmission 30, is increased by 20% within continuously variable transmission 30, and the output rotation speed of continuously variable transmission 30 becomes 2400-3120 rpm.

The second control line D2 indicates that when the load on engine E is above a predetermined level and the output rotation speed of engine E is between 1,400 rpm and 2,000 rpm, the control ratio is 40 to 100%, and the speed increase rate within continuously variable transmission 30 is 8 to 20%. In other words, the output rotation speed of engine E, 1,400 to 2,000 rpm, transmitted to continuously variable transmission 30 is increased by 8 to 20% within continuously variable transmission 30, and the output rotation speed of continuously variable transmission 30 becomes 1,512 to 2,400 rpm.

The first control line D1 indicates that when the load on engine E is above a predetermined level and the output rotation speed of engine E is between 1000 rpm and 1400 rpm, the control ratio is 40% and the speed increase rate within continuously variable transmission 30 is 8%. In other words, the output rotation speed of engine E, 1000-1400 rpm, transmitted to continuously variable transmission 30 is increased by 8% within continuously variable transmission 30, and the output rotation speed of continuously variable transmission 30 becomes 1080-1512 rpm.

As shown in Figure 11, the support device 70, which supports the left-right extending transmission tube (not shown) to which the output rotation of the engine E mounted at the rear of the harvesting device 3 is transmitted, is made up of a left support device 70L located on the front left side of the machine frame 1 and a right support device 70R located on the front right side.

The left support device 70L is made up of a fixed part 71 that is fixed to the machine frame 1, a support shaft 72 that extends upward from the fixed part 71, and a rotating arm 73 that is rotatably fixed to the support shaft 72 and curves upward to the right. A clamping part 74 that clamps the left part of the transmission tube is formed at the top of the rotating arm 73, and a plate-shaped dust cover 75 is attached to the front of the rotating arm 73. This prevents dust from entering the rotating arm 73 and maintains optimal sliding between the sliding parts of the support shaft 72 and rotating arm 73.

The right support device 70R is made up of a fixed part 81 that is fixed to the machine frame 1 and an arm 82 that extends upward from the fixed part 81. Furthermore, a clamping part 83 that clamps the right part of the transmission tube is formed on the upper part of the arm 82.

As shown in Figures 12 and 13, a circular opening 73A is formed in the lower part of the rotating arm 73, and a roughly L-shaped pin 76 is inserted into opening 73A from above. An engaging member 77 is provided on the upper side of the fixed part 71, and two circular openings 77A and 77B are formed in engaging member 77, through which the pin 76 is inserted. Openings 77A and 77B are formed approximately 90 degrees apart in the circumferential direction around the axis of support shaft 72.

When the rotating arm 73 is rotated clockwise around the support shaft 72 to the stored position, the pin 76 is inserted through the openings 73A and 77A. When the rotating arm 73 is rotated counterclockwise around the support shaft 72 to the open position, the pin 76 is inserted through the openings 73A and 77B. This prevents the rotating arm 73 from rotating around the support shaft 72, allowing maintenance work on the harvesting device 3 to be carried out safely.

As shown in Figures 14 and 15, a generally L-shaped opening 75A is formed in the lower part of the dust cover 75 at a location facing the pin 76, and the length of the upper part of the pin 76 is determined so that the upper part of the pin 76 inserted through openings 73A and 77A extends to the front of the dust cover 75 through opening 75A. This allows the pin 76 to be easily attached and detached from openings 77A by moving it vertically from outside the dust cover 75. It is also preferable to provide a lid or the like to cover opening 77A to prevent the upper part of the pin 76 from coming into contact with other components.

As shown in Figures 16 and 17, the clamping portion 83 is made up of a lower clamping portion 83A provided above the arm 82 and having a semicircular arc-shaped notch formed in its upper portion, and an upper clamping portion 83B provided above the lower clamping portion 83A and having a semicircular arc-shaped notch formed in its lower portion.

The upper clamping portion 83B is rotatably fixed to a support shaft 82A extending left and right at the front of the arm 82 via a connector 84. An operating lever 85 extending rearward and upward is provided at the rear of the connector 84 to open and close the upper clamping portion 83B.

A hook member 86 extending downward and rearward is rotatably fixed to a support shaft 85A extending left and right in the middle of the operating lever 85. The tip of the hook member 86 is formed in a roughly J-shape and engages with a pin 87 extending left and right on the upper part of the arm 82.

The hook member 86 is formed from a leaf spring that can deform left and right. This allows the tip of the hook member 86 to be deformed leftward to release the engagement between the hook member 86 and the pin 87, allowing the right part of the transmission tube to be removed from the clamping portion 83.

1 Machine frame 2 Traveling device 3 Harvesting device 4 Threshing device 5 Control unit 16 Main speed change lever (speed change lever)
30 Continuously variable transmission 42 Forward motor 43 Reverse motor 50 Main machine controller (controller)
E engine

Claims (6)

A combine harvester having a traveling device (2) provided below a machine frame (1) on which an engine (E) is mounted, a reaping device (3) provided in front of the machine frame (1), a threshing device (4) provided to the left rear of the reaping device (3), and a control unit (5) provided to the right rear of the reaping device (3),
A continuously variable transmission (30) for increasing/decreasing the output rotation of the engine (E) and switching the rotation direction is provided downstream of the transmission path of the engine (E), and a traveling device (2) is provided downstream of the transmission path of the continuously variable transmission (30),
The control unit (5) is provided with a speed change lever (16) for increasing or decreasing the output rotation of the engine (E) and the output rotation of the continuously variable transmission (30),
When a preset time has elapsed in which the load factor of the engine (E) is 100% or more, and the output rotation of the engine (E) is decelerated to a preset first set output rotation or more below the rated rotation of the engine (E), the controller (50) of the operating section (5) increases or decreases the output rotation of the engine (E) and drives the forward motor (42) and the reverse motor (43) of the continuously variable transmission (30) to decelerate the traveling speed of the traveling device (2) to a preset first set traveling speed, regardless of the operating attitude of the speed change lever (16) ;
A combine harvester characterized in that the set time is set to a time that evens out fluctuations in the load on the engine (E) caused by fluctuations in the amount of straw transported to the threshing device (4) . A combine harvester as described in claim 1, wherein when the output rotation of the engine (E) is decelerated to a first set output rotation or more while being less than the rated rotation of the engine (E), the increase/decrease of the output rotation of the engine (E) is stopped. 3. The combine harvester according to claim 1, wherein the set time is set to 3 seconds. A combine harvester as described in claim 1, wherein, when the output rotation of the engine (E) is slowed below a first set output rotation and reaches or exceeds a predetermined second set output rotation, the output rotation of the engine (E) is increased or decreased, and the forward motor (42) and reverse motor (43) of the continuously variable transmission (30) are driven to slow the traveling speed of the traveling device (2) to a predetermined second set traveling speed that is slower than the first set traveling speed. 5. A combine harvester according to claim 4 , wherein when the output rotation of the engine (E) is decelerated to a second set output rotation or more below a first set output rotation, the increase/decrease of the output rotation of the engine (E) is stopped. 5. The combine harvester according to claim 4 , wherein when the output rotation of the engine (E) is reduced to less than a second set output rotation, the increase/decrease of the output rotation of the engine (E) is stopped.