combine

Abstract

To provide a combine harvester that automatically prevents straw from scattering onto roads or adjacent fields at the start of harvesting in a field. [Solution] A combine harvester is provided with a traveling vehicle body (1) equipped with a traveling device (2), a harvesting device (3) on the front side of the traveling vehicle body (1), a threshing device (4) for threshing and sorting grain stalks on the upper side of the traveling vehicle body (1), a straw cutter (10) for cutting the threshed straw, and a width switching device for switching between wide and narrow diffusion widths on the rear side of the threshing device (4). The combine harvester is provided with a row / lateral mode (M1) for automatically performing perimeter cutting of grain stalks, and the diffusion width of the width switching device is controlled to be narrower when the vehicle body is tilted forward at the start of harvesting work or when perimeter cutting is performed.

Description

Technical Field

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[0001] The present invention relates to a combine that automatically travels in a field.

Background Art

[0002] The combine of Patent Document 1 is provided with a mechanism for adjusting the discharge of straw by a variable diffusion blade of a diffusion spiral of a straw cutting device.

Prior Art Documents

Patent Documents

[0003] [[ID=​​​​​​​​​​​​​​​​​​​​​​​​​In the combine harvester, a mode switching switch (11D) is provided to switch to the row / horizontal mode (M1) used for cutting around grain stalks, and when the front and rear tilt sensor detects a tilt forward of more than a predetermined value and the cutting lever is engaged, the controller (30) switches the width switching device (70) To the right This combine harvester is characterized by its ability to reduce the diffusion width to a predetermined value.

[0007] The invention described in claim 2 is a combine harvester having a traveling vehicle body (1) equipped with a traveling device (2), a harvesting device (3) on the front side of the traveling vehicle body (1), a threshing device (4) for threshing and sorting grain stalks on the upper side of the traveling vehicle body (1), a straw cutter (10) for cutting the straw after threshing and a width switching device (70) for switching the width of the diffusion, wherein a mode switching switch (11D) for switching to a row / cross mode (M1) used for cutting around grain stalks is provided, and the controller (30) is characterized in that when the mode switching switch (11D) detects the row / cross mode (M1), the controller (30) reduces the diffusion width of the width switching device (70) to a predetermined value.

[0008] The invention described in claim 3 is such that the controller (30) operates the width switching device (70) while traveling a predetermined distance after the front and rear tilt sensor detects a forward tilt of a predetermined value or more. To the right The combine harvester according to claim 1 is characterized by controlling the diffusion width to be smaller than a predetermined value.

[0009] The invention described in claim 4 is such that when the controller (30) detects an operation of the operating lever (12) in the left-right direction that exceeds a predetermined value, the width switching device (70) To the right The characteristic is to make the diffusion width smaller than a predetermined value. 1 The combine harvester is as described in claim 3.

[0010] The invention described in claim 5 is such that when the controller (30) detects an operation of the operating lever 12 in the left-right direction that exceeds a predetermined value, the width switching device (70) To the rightThe combine harvester according to claim 4, characterized in that the diffusion width is controlled to be smaller than a predetermined value, and after the operating lever (12) is in the neutral position and the harvester has traveled a predetermined distance, the diffusion width is controlled based on the value of the diffusion switching switch (74). [Effects of the Invention]

[0011] In the invention of claim 1, when the combine harvester enters the ridge at the boundary of the field, the diffusion width of the width switching device (70) can be reduced to a predetermined value, so that the operator does not have to worry about operating the diffusion switching switch (74) and the discharged straw can be prevented from scattering onto the road or adjacent fields.

[0012] In the invention of claim 2, when the combine harvester is in row / horizontal mode (M1) and harvesting around the outer perimeter of the field, the diffusion width of the width switching device (70) can be made smaller than a predetermined value, thereby preventing the discharged straw from scattering onto roads or adjacent fields.

[0013] In the invention of claim 3, when the combine harvester travels a predetermined distance from the ridge at the boundary of the field, by reducing the diffusion width of the width switching device (70) to a predetermined value, the operator can prevent the discharged straw from scattering onto roads or adjacent fields without having to worry about operating the diffusion switching switch (74).

[0014] In the invention of claim 4, when the operator turns the combine harvester, the operator operates the control lever (12) to the left or right by a predetermined value or more, so by making the diffusion width of the width switching device (70) smaller than the predetermined value, it is possible to prevent the discharged straw from scattering onto roads or adjacent fields.

[0015] In the invention of claim 5, except for harvesting work at the edge of the field, after detecting that the operating lever (12) has been moved beyond a predetermined value in the left-right direction, the position of the operating lever 12 remains neutral, and then the diffusion width of the width switching device (70) is reduced to less than a predetermined value, thereby improving the efficiency of harvesting work at the edge of the field. [Brief explanation of the drawing]

[0016] [Figure 1]It is a left side view of the combine. [Figure 2] It is a plan view of the combine. [Figure 3] It is a connection diagram of the positioning unit. [Figure 4] It is a rear view of the combine. [Figure 5] It is a plan view of the diffusion width switching switch [Figure 6] It is a connection diagram of the controller. [Figure 7] It is an explanatory diagram of the reference line and path of the strip / horizontal mode.

Mode for Carrying Out the Invention

[0017] As shown in FIGS.

[0018] An engine room 6 for mounting an engine is provided below the control unit 5, a grain tank 7 for storing threshed and sorted grains is provided behind the control unit 5, and a discharge auger 8 consisting of a vertical grain elevator extending vertically to discharge grains to the outside and a horizontal discharge extending in the front-rear direction is provided behind the grain tank 7.

[0019] A touch-panel monitor 11 that displays the travel speed of the travel device 2 is provided in the center of the front panel in front of the cockpit of the control unit 5, and an operating lever 12 for operating the turning of the travel device 2 and the raising and lowering of the harvesting device 3 is provided to the right of the monitor 11.

[0020] Between the monitor 11 and the operating lever 12, there is a straight-line assist switch 13 that automatically drives the combine along a first reference line 41, which will be described later. Pressing the straight-line assist switch 13 activates the straight-line assist, and the straight-line assist is deactivated when the operator moves the operating lever 12 far to the left or right. The straight-line assist function is a function that allows the combine to automatically drive in a straight line without the operator operating the steering wheel, based on the position information received by the combine's position information acquisition device. The posture of the operating lever 12 is measured by an angle sensor 12A, such as a potentiometer, attached to the base of the operating lever 12.

[0021] A gear shift lever 16 for increasing and decreasing the travel speed of the travel device 2 is provided at the front of the left side panel of the cockpit of the control unit 5, and an inertial measuring device 17 is provided behind the gear shift lever 16. This allows for the measurement of the yawing angle, rolling angle, and pitching angle of the machine frame 1. Near the main gear shift lever 16, a harvesting / threshing lever 18 is provided for operating the connection and disconnection of the harvesting clutch 42 and the threshing clutch 43, and the operating position of the harvesting / threshing lever 18 is measured by an angle sensor 18A such as a potentiometer attached to the base of the harvesting / threshing lever 18.

[0022] As shown in Figure 3, the positioning unit 20, which uses an RTK-GPS positioning system or a differential positioning system, is formed from multiple positioning satellites 21A to 21D, a base station 22 located at a known location, and a mobile station 26 installed on the combine harvester. As a result, positioning signals transmitted from multiple positioning satellites 21A to 21D are received and positioned by GNSS receivers installed on the base station 22 and the mobile station 26. The mobile station 26 can then accurately determine the combine harvester's position by performing high-precision positioning using correction signals from the base station 22.

[0023] The base station 22 consists of a fixed communication device 23, a fixed GPS antenna 24 that receives position information from positioning satellites 21, and a fixed data transmission antenna 25 that transmits correction position information to the mobile station 26.

[0024] The mobile station 26 is comprised of a mobile communication device 27, a mobile GPS antenna 28 that receives position information from positioning satellites 21, and a mobile data receiving antenna 29 that receives correction position information from base station 22. The GPS antenna 28 is preferably positioned at the center of the combine harvester in both the front-to-back and left-to-right directions.

[0025] The threshing device 4 receives and transports the stalks harvested by the harvesting device 3 via a stalk supply device, and the threshed stalks (straw) are transferred from the stalk supply device to a straw transport device for rearward transport. At the rear of the threshing device 4, a straw transport device is provided to transport the stalks (hereinafter referred to as straw) that have been threshed in the threshing drum to the rear. Below the rear of the straw transport device, a cutting chamber 9 is provided to shred the straw transported from the straw transport device and discharge it to the rear of the machine. Straw cutters 10 for shredding the straw are rotatably mounted on the left and right walls of the cutting chamber 9. Below the straw cutters 10, a width switching device 70 is provided to switch the width of the diffusion width of the straw shredded by the straw cutters 10. Furthermore, a dust removal fan is positioned at the rear upper side of the oscillating sorting rack of the threshing device 4 to suck up straw and other debris generated during threshing and sorting and discharge it outside the machine.

[0026] The width switching device 70 is provided with a variable straw-removing body (diffusion guide plate or diffusion guide rod) 72 formed from a pair of left and right shaft rods, and the base of the variable straw-removing body 72 is rotatably attached to a position switching unit 71 having a switching motor 62, which will be described later, and the tip (rear end) of the variable straw-removing body 72 is formed as a free end (Figure 4). The width switching device 70 rotates the tip position of the variable straw-removing body 72 to the left and right relative to the position switching unit 71 by the switching motor 73, Figure 4In this configuration, when positioned on the right side, the diffusion width is "wide," and when positioned on the left side, the diffusion width is "narrow." In this specification, a "narrow" diffusion width is defined as a value smaller than a "wide" diffusion width. Not only are there two levels, "wide" and "narrow," but there can be multiple levels of values. For example, a predetermined value in the multi-level configuration may be used as a reference, with values ​​greater than the predetermined value being defined as "wide" and values ​​smaller than the predetermined value being defined as "narrow."

[0027] For example, the operating positions of the width switching device 70 are configured to include a "wide" position 75 and a "narrow" position 76 for the diffusion width of the diffusion switching switch 74. The controller operates each part based on the operating position of the diffusion switching switch 74 to switch the diffusion width of the width switching device 70.

[0028] <Controller> As shown in Figure 6, the combine harvester's controller 30 is composed of a processing unit 31 consisting of a CPU and the like, a storage unit 32 consisting of ROM, RAM, a hard disk drive, flash memory, and the like, and a communication unit 33 for data communication with the outside.

[0029] The processing unit 31 calculates the first reference line 41, the travel position and direction of the combine harvester, etc., based on the first reference point 41A and the second reference point 41B, which will be described later.

[0030] The memory unit 32 stores location information of the first reference point 41A and the second reference point 41B acquired by the positioning unit 20.

[0031] The input side of the controller 30 is connected via a predetermined input interface circuit to a first reference point setting switch 11A for setting the first reference point 41A, a second reference point setting switch 11B for setting the second reference point 41B, a third reference point setting switch 11C for setting the turning point 41C, a mode switching switch 11D for changing the harvesting mode, an angle sensor 12A for measuring the amount of operation of the operating lever 12, a straight-line assist switch 13 for automatically driving the combine along the first reference line 41, an inertial measuring device 17 for measuring the yawing angle of the combine, a GPS antenna 28 for receiving position information from positioning satellites 21, and a data receiving antenna 29 for receiving correction position information from base station 22. Hereafter, the GPS antenna 28 and the data receiving antenna 29 are collectively referred to as the position information device 34. Switches 11A to 11D are displayed on the monitor screen of monitor 11.

[0032] On the output side of the controller 30, an automatic steering device 35 that automatically drives the combine along the first reference line 41, etc., and a brake 36 that brakes the left and right pair of crawlers of the running gear 2 based on the amount of operation of the operating lever 12 are connected via a predetermined output interface circuit.

[0033] <Reference line> When the operator presses the straight-line assist switch 13, the straight-line assist function is activated. At this time, the processing unit 31 controls the combine harvester to automatically travel in a straight line. Furthermore, the operator selects a harvesting mode so that the harvesting can be performed optimally for the field. The harvesting modes include a row / horizontal mode M1 used for cutting around grain stalks, a reciprocating mode M2 ​​used for reciprocating harvesting or splitting grain stalks, and a one-way mode M3 used for lodging harvesting or one-way harvesting of grain stalks. The processing unit 31 uses a reference line to perform automatic straight-line travel.

[0034] There are two types of reference lines: a first reference line and a second reference line. The first reference line is the standard straight-line direction for automatic straight-line driving and can be arbitrarily determined. The data for the first reference line can be any information that determines the direction, such as the position information of the first reference point and the second reference point, or the direction data connecting the first reference point and the second reference point. The second reference line is the standard straight-line direction for automatic straight-line driving and is orthogonal to the first reference line. The data for the second reference line can be any information that determines the direction, such as the position information of the second reference point and the second reference point that are orthogonal to the first reference line, or the direction data connecting the second reference point and the second reference point. By using the standard straight-line directions of the first and second reference lines and the position information of the starting point of the combined harvester (hereinafter referred to as the starting point), the row and lateral paths of the rectangular field can be determined, and automatic straight-line driving can be performed while continuing harvesting work.

[0035] Figure 7 illustrates a first reference line 41 extending horizontally in the row / horizontal mode M1 set at the top of the field 40, a second reference line 42 extending vertically on the left side, a path 43 extending parallel to the first reference line 41 at the bottom, and a path 44 extending parallel to the second reference line 42 on the right side. In this embodiment, the spacing is predetermined to the cutting width of the harvesting device 3. The arrows in Figure 7 indicate the direction of travel of the combine harvester.

[0036] The first reference line 41 is set as a reference direction by a straight line passing through the first reference point 41A, which is located to the left of the loading area 40A for combine harvesters and other equipment in the field 40, and the second reference point 41B, which is located in front of the first reference point 41A in the direction of travel, and is stored in the memory unit 32. It is preferable that the distance between the first reference point 41A and the second reference point 41B be about 5m.

[0037] The position of the first reference point 41A is determined when the operator presses the first reference point setting switch 11A displayed on the monitor 11. The processing unit 31 stores the position information received by the position information device 34 as the first reference point of the first reference line in the storage unit 32, based on the position information of the combine transmitted from the positioning satellite 21 and base station 22 at the time of the press. Alternatively, the position of the first reference point 41A can also be calculated by the processing unit 31 based on the position information of the combine transmitted from the positioning satellite 21 and base station 22 when the travel distance of the traveling device 2 reaches a predetermined distance, and the same applies to the first reference points 42A, 43A, and 44A described later.

[0038] The position of the second reference point 41B is determined when the operator presses the second reference point setting switch 11B displayed on the monitor 11. The processing unit 31 then uses the position information of the combine harvester transmitted from the positioning satellite 21 and base station 22 at the time of the press, and stores the received position information in the storage unit 32 as the second reference point of the first reference line. Alternatively, the position of the second reference point 41B can also be calculated by the processing unit 31 based on the position information of the combine harvester transmitted from the positioning satellite 21 and base station 22 when the travel distance of the traveling device 2 reaches a predetermined distance, and the same applies to the second reference point 42B, which will be described later.

[0039] The first reference line 41 is a straight line extending in the left-right direction, passing through the first reference point 41A and the second reference point 41B.

[0040] In the path between the first reference point 41A and the second reference point 41B on the first reference line 41, the operator manually controls the combine harvester by operating the control lever 12. Once the combine passes the second reference point 41B, the processing unit 31 automatically controls the combine along the first reference line 41. This reduces the workload on the operator.

[0041] Next, when the operator determines that the combine has reached the turning point 41C in Figure 7, they stop the combine's automatic movement and operate the control lever 12 to rotate the travel device 2 so that the combine's direction of travel is perpendicular to the first reference line 41 and directed downwards. When the operator presses the straight-ahead assist switch 13 and the processing unit 31 detects the input of the straight-ahead assist switch 13, the position information device 34 uses the combined's position information received as the first reference point 42A, calculates a second reference line 42 that passes through the first reference point 42A and is perpendicular to the first reference line 41, and stores the second reference line 42 in the storage unit 32.

[0042] After the second reference line 42 is set, the processing unit 31 automatically moves the combine harvester along the second reference line 42. This reduces the workload on the operator.

[0043] Next, when the operator determines that the combine has reached the turning point 42C in Figure 7, they stop the combine's automatic movement and operate the control lever 12 to rotate the travel device 2 so that the combine's direction of travel is perpendicular to the second reference line 42 and directed to the right. When the operator presses the straight-ahead assist switch 13 and the processing unit 31 detects the input of the straight-ahead assist switch 13, the position information device 34 uses the received position information of the combine as the first reference point 43A, calculates a path 43 that passes through the first reference point 43A and is parallel to the first reference line 41, and stores the path 43 in the storage unit 32.

[0044] After the route 43 is set, the processing unit 31 automatically drives the combine harvester along the route 43. This reduces the workload on the workers.

[0045] Next, when the operator determines that the combine has reached the turning point 43C in Figure 7, they stop the combine's automatic movement and operate the control lever 12 to rotate the travel device 2 so that the combine's direction of travel is perpendicular to the path 43 and directed upward. When the operator presses the straight-line assist switch 13 and the processing unit 31 detects the input of the straight-line assist switch 13, the position information device 34 uses the combined's position information received as the first reference point 44A, calculates a path 44 that passes through the first reference point 44A and is parallel to the second reference line, and stores the path 44 in the storage unit 32.

[0046] After the route 44 is set, the processing unit 31 automatically drives the combine harvester along the route 44. This reduces the workload on the workers.

[0047] Next, when the operator determines that the combine has reached the turning point 44C in Figure 7, they stop the combine's automatic movement and operate the control lever 12 to rotate the travel device 2 so that the combine's direction of travel is perpendicular to the path 44 and directed to the left. When the operator presses the straight-ahead assist switch 13 and the processing unit 31 detects the input of the straight-ahead assist switch 13, the position information device 34 uses the received position information of the combine as the first reference point (not shown), calculates a path 46 that passes through the first reference point and is parallel to the first reference line 41, and stores the path 46 in the storage unit 32.

[0048] After the route 46 is set, the processing unit 31 automatically drives the combine along the route 46. This reduces the workload on the operator. Similarly, the processing unit 31 calculates a route along the first reference route 41 and the second reference line 42, and then automatically drives the combine along the route.

[0049] Based on the above, after acquiring the first reference line 41, the second reference line 42 is also determined based on the first reference line 41, and the combine harvester can be made to automatically travel in a straight line using the two reference directions of the first reference line 41 and the second reference line 42. The operator only needs to stop the combine harvester when it reaches the turning position and perform the turn. After the operation of the control lever 12 is completed (i.e., after the turn is completed), the processing unit 31 activates the straight-line assist switch 13 to enable the straight-line assist function, and then uses the received position information of the combine harvester and the first reference line 41 or the second reference line 42 stored in the storage unit 32 to control the combine harvester's automatic straight-line travel.

[0050] Next, embodiments of the present invention will be described with reference to Figure 7.

[0051] <Example 1> Figure 7 illustrates the path through which the combine harvester enters the field 40 from the edge of the field, the first reference line 41 extending horizontally in the row / horizontal mode M1 set at the top of the field 40, the second reference line 42 extending vertically on the left side, the path 43 extending parallel to the first reference line 41 at the bottom, and the path 44 extending parallel to the second reference line 42 on the right side. In this embodiment, the spacing is set in advance to the cutting width of the harvesting device 3. The arrows in Figure 7 indicate the direction of travel of the combine harvester.

[0052] When the combine harvester enters the field 40 from the edge of the field, the operator sets the threshing lever to the "on" position to begin harvesting. At this time, at the edge of the field, which is the slope outside the field, the controller 30 detects that the combine harvester's front-to-back tilt sensor is tilted forward by a certain amount (for example, 5 degrees), and detects that the threshing lever is in the "on" position. Therefore, by controlling the diffusion width of the width switching device 70 to "narrow," it is possible to prevent the straw from scattering and soiling the surrounding area even if harvesting and threshing begin near the outer edge of the field. The controller 30 controls the diffusion width of the width switching device 70 to "narrow" only while traveling a predetermined distance (for example, 5m), and after traveling the predetermined distance, it may control it based on the value of the diffusion switching switch.

[0053] Next, when the combine enters the field, the operator sets the mode selector switch 11D to row / cross mode M1 and presses the straight-line assist switch 13 to acquire the first reference line 41 and the second reference line 42, and then starts automatic straight-line driving. At this time, when the controller 30 detects that the mode selector switch 11D is in row / cross mode M1, it controls the diffusion width of the width switching device 70 to "narrow". This prevents straw from scattering and soiling the surrounding area even if harvesting and threshing begin near the outer edge of the field.

[0054] Next, the combine harvester automatically travels to the corner of the field, and the operator turns it by operating the turning lever. At this time, when the controller 30 detects that the operating lever 12 has been moved beyond a predetermined value in the left-right direction, it controls the diffusion width of the width switching device 70 to "narrow". This prevents the scattering of straw in the corner of the field.

[0055] Alternatively, the system may be configured to control the diffusion width of the width switching device 70 to "narrow" from the time it is detected that the operating lever 12 has been operated by a predetermined value or more in the left or right direction until the operating lever 12 returns to the neutral position and the combine harvester has traveled a predetermined distance, and then, after the combine harvester has traveled the predetermined distance, to control the diffusion width based on the value of the diffusion switching switch 74 operated by the width switching device 70. This makes it possible to prevent the scattering of straw over a wide area in the corners of the field. In addition, when the diffusion width of the width switching device 70 is controlled to "narrow", the controller 30 can suppress the area over which straw is scattered by controlling the rotation speed of the dust removal fan to a certain level or less.

[0056] <Other Embodiments> Although various embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above and can be implemented in various modified forms. It is applicable not only to combine harvesters but also to other work vehicles such as tractors and rice transplanters. Furthermore, while the operator switches modes by operating a switch on the control unit 5, the controller 30 can be configured to control the automatic steering of the work vehicle in response to operation requests from a remote control device operated from outside the work vehicle. Also, while the operator switches modes by operating the mode switching switch 11 on the control unit 5 and operates the diffusion width of the width switching device 70 using the diffusion switching switch 74, the controller 30 can be configured to control the automatic steering of the work vehicle and the diffusion width of the width switching device 70 in response to operation requests from a remote control device operated from outside the work vehicle. [Explanation of Symbols]

[0057] 1. Aircraft frame 2. Traveling device 3 Reaping device 4. Threshing machine 5. Control Unit 9 Cutting Processing Room 10 Straw Removal Cutter 11D Mode Switch 30 controllers 41. First reference line 42. Second reference line M1 Strip / Horizontal Mode θ Intersection angle 70 width switching device 71 Position switching section 72 Variable Straw Disposal Unit 73 Switching motor 74 Diffusion width selector switch 75 "Wide" position 76 “Narrow” position

Claims

1. In a combine harvester, a harvesting device (3) is provided on the front of a traveling vehicle body (1) equipped with a traveling device (2), a threshing device (4) for threshing and sorting grain stalks is provided on the upper side of the traveling vehicle body (1), a straw cutter (10) for cutting the threshed straw and a width switching device (70) for switching between wide and narrow diffusion widths are provided on the rear side of the threshing device (4), and a control unit (5) for the operator is provided on the rear right side of the harvesting device (3), A mode selector switch (11D) is provided to switch to the row / horizontal mode (M1) used for cutting around grain stalks. The controller (30) is characterized in that when the front and rear tilt sensor detects a forward tilt and the cutting lever is engaged, it reduces the rightward diffusion width of the width switching device (70) to less than a predetermined value.

2. In a combine harvester, a harvesting device (3) is provided on the front of a traveling vehicle body (1) equipped with a traveling device (2), a threshing device (4) for threshing and sorting grain stalks is provided on the upper side of the traveling vehicle body (1), and a straw cutter (10) for cutting the threshed straw and a width switching device (70) for switching between wide and narrow diffusion widths are provided on the rear side of the threshing device (4), A mode selector switch (11D) is provided to switch to the row / horizontal mode (M1) used for cutting around grain stalks. The controller (30) is characterized in that when the mode switching switch (11D) detects a row / horizontal mode (M1), the controller (30) reduces the diffusion width of the width switching device (70) to a predetermined value.

3. The combine harvester according to claim 1, characterized in that the controller (30) controls the rightward diffusion width of the width switching device (70) to be less than a predetermined value while the vehicle has traveled a predetermined distance after the front and rear tilt sensor detects a forward tilt of more than a predetermined value.

4. The combine harvester according to claims 1 to 3, characterized in that when the controller (30) detects an operation of the operating lever (12) in the left-right direction exceeding a predetermined value, the rightward diffusion width of the width switching device (70) is reduced to less than a predetermined value.

5. The combine harvester according to claim 4, characterized in that when the controller (30) detects an operation of the operating lever 12 in the left or right direction exceeding a predetermined value, it controls the rightward diffusion width of the width switching device (70) to be less than a predetermined value, and when the operating lever (12) returns to the neutral position and travels a predetermined distance, it controls the diffusion width based on the value of the diffusion switching switch (74).

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