Lawn mower

Abstract

To provide a highly safe lawnmower. [Solution] The lawnmower comprises a machine body, a cutting blade, a drive unit that rotates the cutting blade, a cutting unit whose tilt relative to the machine body can be adjusted, and a control unit that controls the drive unit. The cutting unit has an operating means that the operator operates when adjusting the tilt of the cutting unit relative to the machine body, and the control unit stops the drive of the drive unit based on the operation of the operating means. The machine body is equipped with a drive operating means that the operator operates when driving the drive unit, and the drive of the drive unit remains stopped until the drive operating means is operated.

Description

Technical Field

[0001] One embodiment of the present invention relates to a lawn mower.

Background Art

[0002] Conventionally, in order to remove weeds and the like growing on the top surface or the side surface of a ridge, lawn mowing work has been regularly performed using a lawn mower. Patent Document 1 discloses a self-propelled lawn mower that performs lawn mowing work on the top surface and the side surface while traveling on a ridge by remote control via wireless communication. The lawn mower described in Patent Document 1 includes a blade portion having a horizontal cutting blade and an inclined cutting blade at the front portion of the machine body, and while traveling, rotates the horizontal cutting blade to remove (mow) weeds and the like growing on the top surface of the ridge, and rotates the inclined cutting blade to remove (mow) weeds and the like growing on the side surface of the ridge. Further, in the lawn mower described in Patent Document 1, by inserting a pin into a hole provided in a plurality of arms connected between the inclined cutting blade and the machine body, the angle of the inclined cutting blade can be adjusted according to the inclination angle of the side surface, and lawn mowing work according to the inclination angle of the side surface of the ridge can be performed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] On the other hand, from the viewpoint of the safety of the operator, for example, when adjusting the inclination angle of the side surface cutting portion, it is preferable that the rotation of the inclined cutting blade is stopped.

[0005] One embodiment of the present invention has been made in view of the above problems, and one of the problems is to provide a highly safe lawn mower.

Means for Solving the Problems

[0006] A lawnmower in one embodiment of the present invention comprises a machine body, a cutting blade, a drive unit that rotates the cutting blade, a cutting unit whose tilt relative to the machine body can be adjusted, and a control unit that controls the drive unit, wherein the cutting unit has an operating means that is operated by an operator when adjusting the tilt of the cutting unit relative to the machine body, and the control unit stops the drive of the drive unit based on the operation of the operating means.

[0007] The aforementioned grass trimmer is equipped with a drive operation means that is operated by an operator when the drive unit is driven, and the control unit does not need to drive the drive unit after stopping the drive of the drive unit based on the operation of the operation means, until the drive operation means is operated again.

[0008] The grass trimmer is equipped with a tilt adjustment mechanism that can adjust the inclination of the cutting section relative to the machine body, and the tilt adjustment mechanism can be switched between a restricted state in which the adjustment of the tilt is restricted and an unrestricted state in which the restriction on the adjustment of the tilt is released by the operator's operation of the operating means, and the control unit may stop the drive of the drive unit based on the operation of the operating means to switch from the restricted state to the unrestricted state.

[0009] The tilt adjustment mechanism comprises a fixed part fixed to the cutting unit and a movable part that is provided so as to be grippable together with the fixed part and is movable relative to the fixed part. The movable part is movable relative to the fixed part when gripped together with the fixed part by the operator, and the movement of the movable part relative to the fixed part may switch from the restricted state to the unrestricted state. [Effects of the Invention]

[0010] According to one embodiment of the present invention, a highly safe lawnmower can be provided. [Brief explanation of the drawing]

[0011] [Figure 1] This is a top view showing the configuration of a lawnmower according to one embodiment of the present invention. [Figure 2] This is a side view showing the configuration of a lawnmower according to one embodiment of the present invention. [Figure 3] This is a rear view showing the configuration of a lawnmower according to one embodiment of the present invention. [Figure 4] This is a perspective view showing the configuration of the slope mowing section of a lawnmower according to one embodiment of the present invention. [Figure 5] This is a side view showing the configuration of the slope mowing unit in one embodiment of the present invention. [Figure 6] This is a side view showing the configuration of the slope mowing unit in one embodiment of the present invention. [Figure 7] This is a side view showing the configuration of the slope mowing unit in one embodiment of the present invention. [Figure 8] This is a rear view showing the configuration of the slope mowing unit according to one embodiment of the present invention. [Figure 9] This is a functional block diagram showing the control system of a lawnmower according to one embodiment of the present invention. [Modes for carrying out the invention]

[0012] The lawnmower of the present invention will be described below with reference to the drawings. However, the lawnmower of the present invention can be implemented in many different forms and should not be interpreted as being limited to the examples shown below. In the drawings referenced in this embodiment, the same part or parts having similar functions will be given the same reference numeral or the same reference numeral followed by an alphabet letter, and repeated explanations will be omitted. In addition, if the same or similar members are provided on the left and right sides in the direction of travel, L (left-side member) or R (right-side member) will be added after the reference numeral of the member. If the left and right members are not particularly distinguished, L and R may be omitted and only the reference numeral will be used to describe the member.

[0013] In the specification of the present application, "up" indicates a direction away from the grassland in the vertical direction when the lawn mower is moving forward while performing a mowing operation on the grassland such as a ridge, and "down" indicates the opposite direction to "up". For the sake of convenience in description, "front" indicates the direction in which the top surface mowing part is located with respect to the traveling part, and "rear" indicates the opposite direction to "front". Also, "left" or "right" indicates "left" or "right" with respect to the rear view of the lawn mower when viewed from the rear of the lawn mower.

[0014] Further, when based on the center line of the lawn mower in a plan view (a line parallel to the traveling direction and passing through the center of the lawn mower), relatively, the side closer to the center line is called "inside", and the side farther from the center line is called "outside".

[0015] In the specification of the present application, ridges, flat ground, and other grasslands where the lawn mower mows grass are collectively called grasslands.

[0016] [1. Configuration of Lawn Mower 100] The lawn mower 100 is a self-propelled lawn mower that performs a mowing operation while traveling. Specifically, the lawn mower 100 is a lawn mower that is remotely controlled by a remote controller and travels on the grassland to perform a mowing operation.

[0017] FIG. 1 is a top view showing the configuration of the lawn mower 100 according to an embodiment of the present invention. FIG. 2 is a left side view showing the configuration of the lawn mower 100 according to an embodiment of the present invention. Specifically, FIG. 2 shows a state in which, when the lawn mower travels on a ridge, the later-described normal surface mowing part 80 (only the left normal surface mowing part 80L is shown in the figure) is adjusted to a position parallel or substantially parallel to the horizontal plane 203 (see FIG. 3). FIG. 3 is a rear view showing the configuration of the lawn mower 100 according to an embodiment of the present invention. Specifically, FIG. 3 shows a state in which, when the lawn mower 100 travels on a ridge, the normal surface mowing part 80 is adjusted to an inclined posture according to the inclination of the normal surface 202 of the ridge 200.

[0018] As shown in FIGS. 1 to 3, the lawn mower 100 includes a machine body 10, a traveling unit 20, a cutting unit 120 including a top surface cutting unit 30 and a slope cutting unit 80, a position adjusting mechanism 90, an inclination adjusting mechanism 130, an engine 60, an alternator 70, a battery 40, a control unit 50, and an anti-tipping means 300. The driving of each unit is controlled by the control unit 50. The lawn mower 100 can perform the lawn mowing operation on the top surface 201 and the slope surface 202 of the ridge 200 in one pass as shown in FIG. 3 by driving and controlling the cutting unit 120 while self-propelling with the traveling unit 20. In FIG. 3, for the sake of simplifying the drawing, the illustration of parts other than the slope cutting unit 80, the position adjusting mechanism 90, and the inclination adjusting mechanism 130 is omitted or simplified. The slope cutting unit 80 may be referred to as the "working unit".

[0019] In FIGS. 1 and 2, the machine body 10 includes a machine body main body 14 that forms the skeleton of the lawn mower 100, and a support case 15 that is attached to the machine body main body 14 and extends forward. The support case 15 may be supported so as to be rotatable in the vertical direction with respect to the machine body main body 14. An attachment member 11 (see FIG. 2) for attaching the top surface cutting unit 30 is provided downward on the support case 15. Further, a pair of left and right slope cutting units 80 are provided behind the machine body main body 14. Although details will be described later, the slope cutting unit 80 is supported by a position adjusting mechanism 90 that adjusts the vertical and horizontal positions of the slope cutting unit 80 and an inclination adjusting mechanism 130 that rotates the slope cutting unit 80 about an axis extending in the traveling direction of the machine body 10 (for example, the rotation axis 185L described later). In other words, the slope cutting unit 80 (working unit) is connected to the machine body 10 (machine body main body 14) so that the inclination with respect to the machine body 10 can be adjusted. The machine body 10 can be configured using a metal material (for example, steel material, aluminum material), a fiber reinforced plastic (FRP) material, etc., but is not limited to this example.

[0020] The travel unit 20 includes a pair of left and right travel units 20L and 20R, and functions as the travel mechanism for the lawnmower 100. In a rear view (see Figure 3), the travel unit 20L is the left travel mechanism in the direction of travel of the lawnmower 100, and the travel unit 20R is the right travel mechanism. Since the structure of the travel unit 20R is the same as that of the travel unit 20L, the explanation here will focus on the travel unit 20L.

[0021] As shown in Figure 2, the running section 20L includes a crawler belt 21L, drive wheels 22L, driven wheels 23L, a crawler frame 24L, and a drive unit 54L. The crawler belt 21L is stretched over the drive wheels 22L and driven wheels 23L and rotates in accordance with the rotation of the drive wheels 22L. The drive unit 54L is driven by power supplied from the alternator 70 or battery 40. The drive wheels 22L rotate due to the power transmitted from the drive unit 54L. The power from the rotation of the drive wheels 22L is transmitted to the driven wheels 23L via the crawler belt 21L. The crawler frame 24L rotatably supports the drive wheels 22L and driven wheels 23L, respectively. In this embodiment, the crawler belt 21L is made of an elastic material (specifically rubber) and has a plurality of lugs (protrusions), and a motor is used as the drive unit 54L.

[0022] As mentioned above, in Figure 1, the mowing unit 120 has a top surface mowing unit 30 located in front of the traveling unit 20, and a slope mowing unit 80 (specifically, a pair of left and right slope mowing units 80L and 80R) located behind the traveling unit 20. As will be described in detail later, the top surface mowing unit 30 is located in front of the machine body 10 and functions as a mowing means to cut weeds and other grass growing on the top surface when mowing the grass on the ridges. The slope mowing unit 80 is located behind the machine body 10 and functions as a mowing means to cut weeds and other grass growing on the slopes when mowing the grass on the ridges. For example, when mowing the grass on the top surface of the ridge and the left and right slopes simultaneously, in a rear view, the top surface mowing unit 30 will be located between the left slope mowing unit 80L and the right slope mowing unit 80R in the left-right direction. Note that the positional relationship between the top surface mowing section 30 and the slope mowing section 80 is not limited to the examples in Figures 1 to 3; for example, the positions of the top surface mowing section 30 and the slope mowing section 80 may be reversed.

[0023] Furthermore, the operations that the slope mowing unit 80 can perform are not limited to mowing grass on slopes; it can also perform grass mowing on grassy areas other than slopes (for example, flat grassy areas). For example, as shown in Figures 1 and 2, if the slope mowing unit 80 is adjusted to a position parallel or approximately parallel to the horizontal plane 203 (see Figure 3), it can perform grass mowing on a plane parallel or approximately parallel to the horizontal plane 203.

[0024] The control unit 50 is, for example, located above the machine body 10 and has the function of controlling the travel unit 20, the cutting unit 120, the engine 60, the alternator 70, or the battery 40. The control unit 50 has, for example, an electronic circuit board 520 (see Figure 9) equipped with a computing device, memory, and communication circuits. In this case, the memory stores a control program for controlling each part of the grass cutter 100, the computing device reads the control program from the memory, and controls each part such as the travel unit 20 based on the control program. The control unit 50 is also connected to a detection means 190 (see Figure 9), which will be described later, for detecting the operating state of the first gripping unit 150 (operating means), which will be described later. Furthermore, the control unit 50 is connected to a drive operation means 530 (see Figure 9), which will be described later, operated by the operator when driving the drive unit 83 of the slope cutting unit 80, which will be described later. Although not shown in the illustration, in this embodiment the drive operation means 530 is provided in the control unit 50. Furthermore, the installation location of the drive operation means 530 is not limited to being located on the control unit 50, but may also be located on the machine body 10, on the slope mowing unit 80, or on the remote controller.

[0025] As shown in Figures 1 to 3, the engine 60 is mounted above the machine body 10. The engine 60 functions as a power source for the drive unit 33 that drives the top surface cutting unit 30, and also as a power source for the alternator 70. The power generated by the engine 60 is transmitted to the drive unit 33 and the alternator 70 via a power transmission means (not shown) consisting of a belt or the like.

[0026] The alternator 70 is located below the support case 15. The alternator 70 generates electricity when power from the engine 60 is transmitted to it. The alternator 70 supplies the generated electricity to the battery 40 and also functions as a power source for the drive unit 83 that drives the slope mowing unit 80 and the drive unit 54 (see Figure 2) that drives the travel unit 20.

[0027] In this embodiment, an example is shown in which an engine 60 is used as the power source to drive the top surface mowing unit 30, but the invention is not limited to this example. For example, it is also possible to use an alternator 70 as the power source to drive the top surface mowing unit 30. That is, it is also possible to drive all of the top surface mowing unit 30, the slope mowing unit 80, and the travel unit 20 with power supplied from the alternator 70 or the battery 40.

[0028] The alternator 70 in this embodiment is equipped with a power generation control circuit (not shown) for controlling power generation. The lawnmower 100 has a sensor that detects the battery voltage of the battery 40, and the power generation control circuit monitors the results detected by the sensor, so that the alternator 70 can control its power generation state itself. The power generation control circuit controls the alternator 70 so that if the battery voltage of the battery 40 falls below a predetermined value, it generates power and enters a power supply state, and if the battery voltage of the battery 40 exceeds a predetermined value, it enters a power supply stop state.

[0029] The battery 40 is detachably mounted at the rear of the control unit 50. The battery 40 stores the electricity generated by the alternator 70. The battery 40 functions as a power source, supplying the stored electricity to the drive unit 83 that drives the slope mowing unit 80 and the drive unit 54 that drives the travel unit 20. The electricity stored in the battery 40 may also be used as a power source for the control unit 50. The battery 40 can be installed anywhere above the machine body 10, but in this embodiment, considering the overall weight balance of the grass trimmer 100 and the ease of attachment and detachment when replacing the battery 40, the battery 40 is placed at the rear of the control unit 50 (machine body 10).

[0030] Although not shown in the diagram, the lawnmower 100 may include a cover member that covers the battery 40, the control unit 50, and the engine 60, and protects each part. The cover member may be configured to cover a portion of the battery 40, the control unit 50, and the engine 60.

[0031] The anti-tipping means 300L and 300R are arranged side by side on the left and right running sections 20L and 20R respectively, and prevent the lawnmower 100 from tipping over in the left or right direction during grass cutting work. The anti-tipping means 300 includes a support frame 310, a main arm 320, and an auxiliary arm 330. The support frame 310 is attached to the side of the running section 20 by a mounting member 17 (see Figure 2; however, only the mounting member 17L is shown in Figure 2) which is connected to the machine body 14 and the crawler frame 24.

[0032] One front end of the main arm 320 is rotatably connected to the support frame 310, and the main arm 320 is rotatably supported by the support frame 310. The auxiliary arm 330 is an extendable member that spans between the support frame 310 and the main arm 320, and is configured to be fixed at a predetermined length. By extending or retracting the auxiliary arm 330, the main arm 320 can be rotated. Specifically, when the auxiliary arm 330 is extended, the main arm 320 rotates downward and protrudes outward, and when the auxiliary arm 330 is retracted, the main arm 320 rotates upward and is held toward the machine body. When performing grass cutting work, by extending the auxiliary arm 330 and rotating the main arm 320 downward, and fixing the auxiliary arm 330 at a predetermined length, the protruding main arm 320 can contact the field or grassland and support the grass cutter 100 when the grass cutter 100 tilts. Furthermore, it is possible to place a component that can ensure a large contact area at the part of the main arm 320 that contacts the field. For example, if a plate-shaped component is attached to the rear end of the main arm 320, when the brush cutter 100 tilts, the plate-shaped component will function as a contact point with the field, thereby distributing the load on the main arm 320 (the weight of the brush cutter 100).

[0033] The configuration of the mowing section 120 (specifically, the top surface mowing section 30 and the slope mowing section 80) will be explained in detail below using Figures 1 to 3.

[0034] [2. Configuration of the top surface cutting section 30] The configuration of the top surface cutting unit 30 will now be described. As shown in Figure 1, the top surface cutting unit 30 includes a casing 31, two blade sections 32L and 32R arranged side by side, and drive sections 33L and 33R corresponding to the blade sections 32L and 32R, respectively. The drive sections 33L and 33R are each connected to a mounting member 11. The casing 31 covers the top and sides of the blade section 32, preventing soil, pebbles, grass, etc. from scattering into the surrounding area. The casing 31 may be called a cover section, and the side of the blade section 32 not covered by the casing 31 faces the top surface 201 of the ridge 200. The structure of the blade section 32R and the drive section 33R is the same as the structure of the blade section 32L and the drive section 33L, respectively.

[0035] As shown in Figure 2, the top cutting section 30 is supported so as to be suspended from the support case 15 via the mounting member 11. The blade section 32 is composed of multiple grass-cutting blades. The blade section 32 is connected to the rotating shaft of the drive unit 33, and the rotation of the rotating shaft of the drive unit 33 causes the blade section 32, including the multiple grass-cutting blades, to rotate. These rotating grass-cutting blades perform the grass-cutting work on the grassland. The drive unit 33 utilizes the driving force of the engine 60, transmitted via a power transmission means (not shown) including a belt (not shown), as the driving force (rotational power) for the blade section 32.

[0036] In this embodiment, the two blade sections 32L and 32R are arranged symmetrically or substantially symmetrically with respect to the center line 110 of the machine body 10, and are positioned with a phase difference so that the mowing blades do not interfere with each other when stationary. The power transmission means is designed to transmit the driving force of the engine 60, transmitted via a belt, equally or substantially equally to both the drive units 33L and 33R. Therefore, the multiple mowing blades of blade section 32L and the multiple mowing blades of blade section 32R rotate at the same timing and speed.

[0037] In this embodiment, an example is shown in which an engine 60 is used as the power source for rotating the blade portion 32 of the top surface cutting section 30. However, if an alternator 70 is used as the power source for rotating the blade portion 32, a motor can be used as the drive unit 33. In this case, the control unit 50 may be used to independently control the drive units 33L and 33R, respectively, and the blade portions 32L and 32R may be driven independently. Furthermore, in this case, the power to drive the motor can be supplied from the alternator 70 or the battery 40.

[0038] [3. Structure of the slope mowing section 80] The structure of the slope mowing section 80 will now be described. The slope mowing section 80 includes a pair of left and right slope mowing sections 80L and 80R. As shown in Figures 1 and 2, the slope mowing sections 80L and 80R each include casings 81L and 81R, blade sections 82L and 82R, drive sections 83L and 83R corresponding to the blade sections 82L and 82R, and second gripping sections 140L and 140R. The casing 81, like the casing 31 of the top surface mowing section 30, may be called a cover section and covers the top and sides of the blade section 82 to prevent the scattering of soil, pebbles, grass, etc. to the surroundings. The structure of the slope mowing section 80R is the same as that of the slope mowing section 80L.

[0039] As shown in Figure 2, the blade section 82 has multiple grass-cutting blades. The blade section 82 is connected to the rotating shaft of the drive unit 83, which is driven by power from the alternator 70 or the battery 40, and rotates. That is, the rotation of the rotating shaft of the drive unit 83 causes the blade section 82, which includes the multiple grass-cutting blades, to rotate, and the grass-cutting work is performed by the blade section 82. For example, a motor can be used as the drive unit 83. The drive unit 83L and the drive unit 83R can be driven independently of each other. That is, the grass cutter 100 can perform grass-cutting work by independently controlling the slope cutting section 80L and the slope cutting section 80R.

[0040] The second gripping parts 140L and 140R are components that the operator grips when adjusting the inclination of the slope mowing section 80L and the slope mowing section 80R relative to the machine body 10, or when moving the slope mowing section 80L and the slope mowing section 80R up and down. The second gripping part 140L is provided near the left end of the casing 81L, and the second gripping part 140R is provided near the right end of the casing 81R. However, the installation positions of the second gripping parts 140L and 140R are not limited to the left end of the casing 81L and the right end of the casing 81R, and they may be installed anywhere on the casing 81L and casing 81R.

[0041] As shown in Figures 1 and 3, the slope mowing sections 80L and 80R are supported on the machine body 14 via position adjustment mechanisms 90L and 90R, and tilt adjustment mechanisms 130L and 130R, respectively. Since the position adjustment mechanism 90 is rotatably connected to the machine body 14, the slope mowing section 80 is also rotatable relative to the machine body 14.

[0042] The position adjustment mechanism 90 is a mechanism for moving the slope mowing unit 80 to follow the shape of the slope when the slope mowing unit 80 performs grass cutting work on the slope. It adjusts the position of the slope mowing unit 80 in the left-right direction to match the width of the ridge (ridge width), and adjusts the position of the slope mowing unit 80 in the up-down direction to match the height and undulation of the slope. The position adjustment mechanism 90 is equipped with a parallel link structure for moving the slope mowing unit 80 in the vertical direction parallel to the main body 14, and a parallel link structure for moving the slope mowing unit 80 in the left-right direction parallel to the slope. These two parallel link structures allow the slope mowing unit 80 to be moved in the up-down and left-right directions parallel to the slope without changing its posture. In other words, when the position adjustment mechanism 90 operates in response to changes in ridge width or changes in the height and undulation of the slope, the slope mowing unit 80 moves in the up-down and left-right directions parallel to the slope by the two parallel link structures, so its posture does not change relative to the slope, and grass cutting work can be performed efficiently.

[0043] The tilt adjustment mechanisms 130L and 130R are connected to the position adjustment mechanisms 90L and 90R, and the slope mowing sections 80L and 80R, respectively. The slope mowing section 80 is connected to the machine body 10 so that its tilt relative to the machine body 14 can be adjusted by the operation of the tilt adjustment mechanism 130. Specifically, as shown in Figure 3, the tilt adjustment mechanism 130 is configured so that the angle (angle α2) between the mowing surface 204 of the slope mowing section 80 and the lower surface of the machine body 14 (the same plane as the plane 206 shown in Figure 3) can be adjusted according to the inclination angle of the slope 202 of the ridge 200 (the same angle α1 as the angle between the horizontal plane 203 and the mowing surface 204). In the following description, "lower surface of the machine body 14" is synonymous with the plane 206 shown in Figure 3. The "cutting surface 204" refers to the surface that includes the trajectory of the blade portion 82 (see Figure 2) of the slope cutting section 80 when cutting grass (shown by a dashed line in Figure 3), and can also be called the cut surface of the grass during grass cutting. The configurations of the tilt adjustment mechanisms 130L and 130R will be explained in detail later.

[0044] Furthermore, as shown in Figures 1 and 2, the slope mowing sections 80L and 80R each include mowing height adjustment sections 400L and 400R, respectively. The mowing height adjustment section 400L includes a roller support section 420L that rotatably supports the roller 410L. Similarly, the mowing height adjustment section 400R includes a roller support section 420R that rotatably supports the roller 410R.

[0045] As shown in Figure 1, the front end of the roller support section 420 is rotatably supported via a bracket erected on the upper surface of the casing 81, and both extend rearward from near the rear end of the slope mowing section 80. An adjustment section for adjusting the rotational position of the roller support section 420 using a positioning pin is also provided on the upper surface of the casing 81.

[0046] The roller 410 extends to the left and right from the roller support 420 and is rotatably connected to the roller support 420. Also, as shown in Figure 2, the roller 410L is suspended from the roller support 420L. The roller 410 is a frustoconical rotating body. The axis of rotation of this frustoconical shape is the center of rotation of the roller 410L and is inclined downward with respect to the roller support 420L so that the lower end of the circumferential surface of the roller 410 is parallel or approximately parallel to the mowing surface 204 of the slope mowing section 80, that is, so that the lower end of the circumferential surface of the roller 410 is parallel or approximately parallel to the ground which serves as the work surface. Furthermore, the axis of rotation of this frustoconical shape is inclined to move backward as it moves away from the connection point with the roller support 420L, that is, when viewed from above, it is positioned further back as it moves outward. The bottom surface of the frustoconical shape of the roller 410 is closer to the roller support 420 than the top surface. In other words, the diameter of the roller 410 gradually decreases as it moves away from the roller support portion 420.

[0047] As described above, the slope mowing unit 80 is configured to move in accordance with the shape of the slope by the operation of the position adjustment mechanism 90. As shown in Figure 3, the slope mowing unit 80 is configured such that the roller 410 contacts the slope 202 of the ridge 200, maintaining the distance from the mowing surface 204 to the slope 202 (corresponding to the mowing height) at a predetermined distance H1. In other words, the slope mowing unit 80 can maintain a constant mowing height for the grass growing on the slope 202, according to the undulations of the slope 202 of the ridge 200. Furthermore, the position of the roller 410 relative to the slope mowing unit 80 can be adjusted by inserting the positioning pin while the roller support unit 420 is at a predetermined rotation angle. Therefore, the height of the mowing surface 204 relative to the slope 202 can be adjusted. Furthermore, the configuration for adjusting the position of the roller 410 relative to the slope mowing section 80 is not limited to a configuration in which a positioning pin is inserted; any configuration that allows for adjustment of the position of the roller 410 relative to the slope mowing section 80 may be adopted.

[0048] As described above, the lawnmower 100 of this embodiment can move the slope mowing section 80 in the up, down, left, and right directions by the operation of the position adjustment mechanism 90, and can perform grass cutting work without changing the posture of the slope mowing section 80 in response to changes in the width of the ridge or changes in the height and undulation of the slope. Providing a cutting height adjustment section 400 on the slope mowing section 80 is very useful for making the operation of such a position adjustment mechanism 90 function effectively. The lawnmower 100 can maintain a predetermined distance from the mowing surface 204 to the slope 202 by the cutting height adjustment section 400, so that the casing 81 of the slope mowing section 80 does not come into contact with the ridge 200, and the position adjustment mechanism 90 can perform smooth parallel movement of the slope mowing section 80.

[0049] As described above, in this embodiment, a configuration in which the slope mowing unit 80 can move in the up, down, left, and right directions by the position adjustment mechanism 90 has been illustrated, but the present invention is not limited to this configuration. The position adjustment mechanism 90 may be omitted, and the slope mowing unit 80 may be connected to the machine body 10 via the tilt adjustment mechanism 130. In other words, the slope mowing unit 80 may not be able to move in the up, down, left, and right directions, and only the tilt can be adjusted by the tilt adjustment mechanism 130. However, the position adjustment mechanism 90 may be configured to move only in the up and down direction, or it may be configured to move only in the left and right direction.

[0050] [4. Configuration of the tilt adjustment mechanism 130] The configuration of the tilt adjustment mechanism 130 will be explained using Figures 4 to 7. Figure 4 is a perspective view showing the configuration of the slope mowing section 80L, position adjustment mechanism 90L, and tilt adjustment mechanism 130L of a grass mower according to one embodiment of the present invention. Figures 5 to 7 are side views showing the configuration of the slope mowing section 80L, position adjustment mechanism 90L, and tilt adjustment mechanism 130L according to one embodiment of the present invention. Figures 5 to 7(A) are views of the slope mowing section 80L, position adjustment mechanism 90L, and tilt adjustment mechanism 130L from the left side, respectively. However, members such as the drive unit 83L, second gripping unit 140L, roller 410L, and roller support unit 420L shown in Figure 4(A) are omitted, and cross-sections of some components related to the tilt adjustment mechanism 130L (for example, the connecting unit 175L and reinforcing member 176L, which will be described later) are shown. Also, Figure 4(B) shows the top surface of the first gripping unit 150L, ​​which will be described later. In Figure 4(B), the movable part 160L is located below the rod-shaped member 154L and is hidden by the rod-shaped member 154L, so it is not shown. Also, Figures 5 to 7(B) illustrate the positional relationships of the movable part 160L, the restricted part 170L, the fixed contact 191L, the movable contact 192L, and the interlocking part 195L of the detection means 190, which will be described later, in the state shown in Figures 5 to 7(A), respectively. The configuration of the tilt adjustment mechanism 130R is the same as that of the tilt adjustment mechanism 130L, so the explanation will focus on the tilt adjustment mechanism 130L.

[0051] The tilt adjustment mechanism 130L is a mechanism that adjusts the tilt of the slope mowing section 80 relative to the machine body 10 by rotating the slope mowing section 80L around an axis (rotation axis 185L, described later) that extends in the direction of travel of the machine body 10 when it is moving forward, in response to the operator's operation of the first gripping section 150L, ​​which will be described later. The slope mowing section 80L is connected to the position adjustment mechanism 90L via the tilt adjustment mechanism 130L (more specifically, the connecting section 175L). As will be described in detail later, the tilt adjustment mechanism 130L is a mechanism that can switch between a "restricted state" and an "unrestricted state" in response to the operator's operation of the first gripping section 150L (described later). The restricted state is a state in which the adjustment of the tilt of the slope mowing section 80 relative to the machine body 10 is restricted. The unrestricted state is a state in which the restriction on the adjustment of the tilt is removed. Specifically, the tilt adjustment mechanism 130L can adjust the tilt (rotation position) of the slope mowing unit 80L relative to the machine body 10 (for example, the machine body main body 14) when the restriction is released, and when the restriction is in place, it restricts the tilt (rotation position) of the slope mowing unit 80L to a predetermined rotation angle that has been adjusted or to a predetermined range of rotation angles that includes the predetermined rotation angle that has been adjusted.

[0052] As shown in Figures 4 to 7, the tilt adjustment mechanism 130L comprises a first gripping part 150L, ​​a restricted part 170L, a connecting part 175L, and a tilt positioning member 180L. In addition, a detection means 190L is provided near the tilt adjustment mechanism 130L to detect the operation of the first gripping part 150L by the operator, which will be described later, and more specifically, the movement of the movable part 160L relative to the fixed part 151L which will be described later.

[0053] The first gripping section 150L comprises a fixed section 151L fixed to the slope mowing section 80L, and a movable section 160L that is provided to be grippable together with the fixed section 151L and is movable relative to the fixed section 151L. As will be described in detail later, the movable section 160L is connected to a rod-shaped member 173L of the restricted section 170L, which will be described later, and when the operator rotates the movable section 160L, the rod-shaped member 173L moves back and forth (advance and retreat).

[0054] The fixing section 151L comprises a pair of leg-shaped members 152L provided on the upper surface of the casing 81L, a plate 153L fixed to the upper ends of the leg-shaped members 152L so as to span the pair of leg-shaped members 152L, and a rod-shaped member 154L fixed to the upper surface of the plate 153L and gripped by an operator.

[0055] As shown in Figure 5, the movable part 160L is a lever-shaped member rotatably supported by a pivot shaft 164L fixed between a pair of leg-shaped members 152L, and has a first arm portion 161L and a second arm portion 162L. The movable part 160L is configured in a roughly "V" shape, and a bearing portion is provided in the bent portion where the first arm portion 161L and the second arm portion 162L are connected, through which the pivot shaft 164L is inserted. The movable part 160L is rotatable around the pivot shaft 164L. The movable part 160L, together with the rod-shaped member 154L of the fixed part 151L, is positioned so that it can be grasped by an operator.

[0056] The first arm portion 161L is the part that is operated (gripped) by the operator, and a bent portion 166L is provided at the rear end of the first arm portion 161L, i.e., near the rotating end, on which a hook 155L provided on the rod-shaped member 154L, which will be described later, can be hooked. The second arm portion 162L is the part that is connected to the connecting portion 171L of the restricted portion 170L and the interlocking portion 195L of the detection means 190 via a pin 172L of the restricted portion 170L, which will be described later, and an insertion hole (not shown) for inserting the pin 172L is provided near the lower end. By inserting the pin 172L through this insertion hole, an elongated hole (not shown) provided in the connecting portion 171L (described later), and an elongated hole 196L (same shape as the elongated hole provided in the connecting portion 171L) provided in the interlocking portion 195L, the movable portion 160L (second arm portion 162L) is connected to the restricted portion 170L and the interlocking portion 195L of the detection means 190.

[0057] Furthermore, a biasing part 165L is provided between the movable part 160L and the casing 81L. The biasing part 165L biases the movable part 160L away from the fixed part 151L. In other words, the biasing part 165L applies rotational force to the movable part 160L in the R1 direction (downward). As will be described in detail later, when the biasing part 165L biases the movable part 160L, the rod-shaped member 173L of the restricted part 170L, which will be described later, receives a force in the direction of insertion into the tilt positioning member 180L, which will be described later, and more specifically, in the direction of entering the restricting parts 186L to 189L (see Figure 8) provided on the tilt positioning member 180L, which will be described later. In this embodiment, a spring (a coil spring in this embodiment) is used as the biasing part 165L. However, the configuration of this embodiment is not limited to any other material that can apply force to the rod-shaped member 173L in the direction of insertion into the tilt positioning member 180L, more specifically, in the direction of entering the restricting portions 186L to 189L described later, which are provided on the tilt positioning member 180L. It is also possible to use a torsion coil spring as the biasing portion 165L. Furthermore, elastic members other than springs may be used, and members without elasticity may also be used.

[0058] As shown in Figures 5 to 7, the movable part 160L can be rotated around the pivot axis 164L by being grasped by the worker together with the fixed part 151L, and is movable relative to the fixed part 151L. Specifically, when the worker grasps the movable part 160L together with the fixed part 151L, the movable part 160L rotates in the R2 direction (upward) so as to approach the fixed part 151L. On the other hand, when the worker releases the fixed part 151L and the movable part 160L from being grasped, the biasing force of the biasing part 165L causes the movable part 160L to rotate in the R1 direction (downward) so as to move away from the fixed part 151L.

[0059] A hook 155L is rotatably connected near the rear end of the fixed portion 151L. The hook 155L is ring-shaped. When the movable portion 160L rotates in the R2 direction and approaches the fixed portion 151L, the hook 155L is hooked onto the bent portion 166L of the movable portion 160L, thereby restricting the rotation of the movable portion 160L in the R1 direction (the direction in which the movable portion 160L moves away from the fixed portion 151L).

[0060] The restricted portion 170L has a rod-shaped member 173L, a connecting portion 171L that supports the rod-shaped member 173L, and a pin 172L that are detachably positioned to insert into a through hole 177L provided in the connection portion 175L of the tilt adjustment mechanism 130L (described later) and a through hole provided in the reinforcing member 176L. The rod-shaped member 173L includes a rod-shaped portion 173L1 that is inserted into and removed from the through hole 177L and the through hole provided in the reinforcing member 176L, and a plate-shaped mounting portion 173L2 that extends rearward from the rod-shaped portion 173L1. The mounting portion 173L2 is sandwiched and fixed between the connecting portion 171L and the fixing portion 195L2 of the interlocking portion 195L (described later). The rod-shaped member 173L is connected to the movable portion 160 (the second arm portion 162L) of the first gripping portion 150L via the connecting portion 171L and the pin 172L. The connecting portion 171L is a flat plate-shaped member, to which the mounting portion 173L2 of the rod-shaped member 173L is connected and fixed on the outer side (left side) of the front end, and an elongated hole is formed on the rear end through which a pin 172L is inserted. The pin 172L is inserted through an elongated hole provided on the rear end of the connecting portion 171L, an insertion hole provided on the second arm portion 162L, and an elongated hole 196L provided on the rear end of the interlocking portion 195L, which has the same shape as the elongated hole of the connecting portion 171L. The pin 172L is configured to slide inside the elongated hole of the connecting portion 171L and the elongated hole 196L of the interlocking portion 195L. Note that the connecting portion 171L and the interlocking portion 195L may be made from a single member.

[0061] When the movable part 160L is rotated, as described above, the pin 172L slides along the inner wall of the elongated hole in the connecting part 171L and the elongated hole 196L in the interlocking part 195L, causing the connecting part 171L and the interlocking part 195L to move back and forth. The rod-shaped member 173L is inserted through the through hole 177L provided in the connecting part 175L and the through hole provided in the reinforcing member 176L, which will be described later. When the connecting part 171L and the interlocking part 195L move back and forth, the rod-shaped member 173L moves linearly in the front-to-back direction, using these through holes as a guide (moving in / out). In other words, the rotational motion of the movable part 160L is converted into linear motion (retraction / retraction) of the rod-shaped member 173L by the pin 172L, the elongated hole 196L in the connecting part 171L and the elongated hole 195L in the interlocking part 195L, and the through hole 177L in the connecting part 175L and the through hole in the reinforcing member 176L. Specifically, as the movable part 160L rotates in the R2 direction, the pin 172L slides backward along the side walls of the elongated hole 171L in the connecting part 171L and the elongated hole 196L in the interlocking part 195L, applying force to the connecting part 171L and the interlocking part 195L, causing the connecting part 171L and the interlocking part 195L to move backward. As a result, the rod-shaped member 173L moves linearly backward together with the connecting portion 171L and the interlocking portion 195L, sliding (using as a guide) through the through hole 177L provided in the connecting portion 175L and the through hole provided in the reinforcing member 176L, which will be described later. In addition, as the movable portion 160L rotates in the R1 direction, the pin 172L slides forward along the side walls of the elongated hole 171L in the connecting portion 171L and the elongated hole 196L in the interlocking portion 195L, applying force to the connecting portion 171L and the interlocking portion 195L, causing the connecting portion 171L and the interlocking portion 195L to move forward. As a result, the rod-shaped member 173L moves linearly forward, sliding (using as a guide) through the through hole 177L provided in the connecting portion 175L and the through hole provided in the reinforcing member 176L. Furthermore, the second arm portion 162L, which is connected to the rod-shaped member 173L via the connecting portion 171L and the interlocking portion 195L, is shorter than the first arm portion 161L. Therefore, by lever principle, even if the first arm portion 161L is rotated with a small operating force, the rod-shaped member 173L can be moved back and forth, and the operator can switch between the restricted state and the unrestricted state with little force.

[0062] Furthermore, the configuration is not limited to the rod-shaped member 173L moving in the front-rear direction as in this embodiment. The rod-shaped member 173L may also move in the up-down direction as the movable part 160L rotates, or it may move in the left-right direction as the movable part 160L rotates. Moreover, it is desirable that the shape of the rod-shaped member 173L corresponds to the direction of movement of the rod-shaped member 173L. In addition, the restricted part 170L is not limited to the configuration using the rod-shaped member 173L as in this embodiment. For example, the restricted part 170L may clamp the tilt positioning member 180L as the movable part 160L rotates.

[0063] The connecting portion 175L is fixed to the upper surface of the casing 81. The connecting portion 175L has a roughly U-shaped form when viewed from the side. A reinforcing member 176L is provided on the rear end side wall of the connecting portion 175L. A through hole 177L (see Figure 6) is provided on the rear end side wall of the connecting portion 175L through which a rod-shaped member 173L (rod-shaped portion 173L1) is inserted, and a through hole is also provided on the reinforcing member 176L through which the rod-shaped member 173L (rod-shaped portion 173L1) is inserted. The reinforcing member 176L is fixed to the rear end side wall of the connecting portion 175L such that the through hole provided on the reinforcing member 176L communicates with the through hole 177L provided on the rear end side wall of the connecting portion 175L. In addition, a pivot shaft 185L is provided between the front end side wall and the rear end side wall of the connecting portion 175L, and is fixed to these side walls.

[0064] The tilt positioning member 180L is configured in a roughly inverted U-shape, with its upper surface fixed to the lower surface of the fixing part 901L at the rear end of the position adjustment mechanism 90L. The tilt positioning member 180L is positioned to fit inside the connecting part 175L. Through holes are provided in the side walls at the front and rear ends of the tilt positioning member 180L, and the pivot shaft 185L is inserted through these through holes. The connecting part 175L and the tilt positioning member 180L are rotatably connected and supported by the pivot shaft 185L. The detailed configuration of the tilt positioning member 180L will be described later, but the tilt positioning member 180L is provided with a plurality of restricting parts 186L to 189L (see Figure 8) into which the rod-shaped member 173L (rod-shaped part 173L1) can enter.

[0065] Figure 5 shows the state in which the rod-shaped member 173L (rod-shaped portion 173L1) has entered the restricting portion 186L (see Figure 8(B)) of the tilt positioning member 180L, which will be described later. As described above, the movable portion 160L is subjected to a rotational force in the R1 direction by the biasing portion 165L, and the movable portion 160L rotates in the R1 direction relative to the fixed portion 151L. Accordingly, the rod-shaped member 173L, the connecting portion 171L, and the interlocking portion 195L move forward in conjunction, and when the rod-shaped member 173L (rod-shaped portion 173L1) is inserted into (entered into) one of the restricting portions 186L to 189L of the tilt positioning member 180L, as shown in Figure 5, the adjustment of the tilt of the slope mowing portion 80L is restricted. At this time, at least a portion of the rod-shaped member 173L (rod-shaped portion 173L1) may be in contact with the inclined positioning member 180L, the through hole 177L, and the through hole provided in the reinforcing member 176L. This state is the aforementioned "restricted state".

[0066] Figure 6 shows the state in which, starting from the state shown in Figure 5, the worker grips the movable part 160L together with the fixed part 151L, causing the movable part 160L to rotate in the R2 direction (upward) and bringing the movable part 160L and the fixed part 151L into contact. As the movable part 160L rotates in the R2 direction, the pin 172L slides against the side wall of the elongated hole 171L of the connecting part 171L and the elongated hole 196L of the interlocking part 195L, pushing the connecting part 171L and the interlocking part 195L backward, causing the rod-shaped member 173L, the connecting part 171L, and the interlocking part 195L to move backward in conjunction. As a result, as shown in Figure 6, the rod-shaped member 173L (rod-shaped portion 173L1) is positioned in an unrestricted position, as described later, having moved out of (retracted from) any of the restricting portions 186L to 189L described later on the tilt positioning member 180L, and the restriction on the rotation of the slope mowing section 80L is released. As a result, the slope mowing section 80L can be freely rotated by the tilt adjustment mechanism 130L, and the tilt of the slope mowing section 80L can be adjusted. At this time, the rod-shaped member 173L (rod-shaped portion 173L1) is not in contact with the tilt positioning member 180L and the through hole 177L, and a part of the rod-shaped member 173L (rod-shaped portion 173L1) may be in contact with the through hole provided in the reinforcing member 176L. This state is the "restriction-released state" described above.

[0067] Figure 7 shows the state shown in Figure 6 (the worker is gripping the movable part 160L together with the fixed part 151L), after which the worker operates the hook 155L to hook the hook 155L onto the movable part 160L, and then releases the grip on the movable part 160L (releases the hand from the movable part 160L). Note that after hooking the hook 155L onto the movable part 160L and then releasing the grip on the movable part 160L, the biasing force of the biasing part 165L causes the movable part 160L to rotate in the R1 direction from the state shown in Figure 6. As the movable part 160L rotates in the R1 direction, the pin 172L slides against the side wall of the elongated hole 171L of the connecting part 171L and the elongated hole 196L of the interlocking part 195L, pushing the connecting part 171L and the interlocking part 195L forward. As a result, the rod-shaped member 173L, the connecting part 171L, and the interlocking part 195L move forward in conjunction. However, as shown in Figure 7, the hook 155L restricts the rotation of the movable part 160L in the R1 direction to a predetermined angle. The hook 155L is sometimes called a "stopper". As shown in Figure 7, the rod-shaped member 173L (rod-shaped part 173L1) is in an unrestricted position described later, where it has disengaged (retracted) from any of the restricting parts 186L to 189L described later on the tilt positioning member 180L, and the forward movement of the rod-shaped member 173L is restricted by the stopper. At this time, the rod-shaped member 173L (rod-shaped portion 173L1) is not in contact with the tilt positioning member 180L, and a part of the rod-shaped member 173L (rod-shaped portion 173L1) may be in contact with the through hole provided in the reinforcing member 176L. Even when the worker is not gripping the fixed portion 151L and the movable portion 160L, the tilt adjustment restriction of the slope mowing section 80L by the tilt adjustment mechanism 130L is released. The states shown in Figures 6 and 7 are both states in which the tilt adjustment restriction of the slope mowing section 80 is released, so these states also correspond to the aforementioned "restriction release state".

[0068] In the state shown in Figure 7, the worker grasps the movable part 160L together with the fixed part 151L and rotates the movable part 160L in the R2 direction, releasing the hook 155L from the bent part 166L of the movable part 160L and releasing the grip on the movable part 160L. As a result, the movable part 160L rotates in the R1 direction due to the biasing force of the biasing part 165L. As the movable part 160L rotates in the R1 direction, the pin 172L slides against the side wall of the elongated hole in the connecting part 171L and the elongated hole 196L of the interlocking part 195L, pushing the connecting part 171L and the interlocking part 195L forward, causing the rod-shaped member 173L to move forward. As a result, it returns to the state shown in Figure 5. When the state of the tilt adjustment mechanism 130L returns to the state shown in Figure 5, the tilt adjustment mechanism 130L is in the "restricted state".

[0069] As described above, by operating the first gripping part 150L (operating means), the operator can switch between a "restricted state" in which the tilt adjustment is restricted and a "removed restriction state" in which the tilt adjustment is removed. Specifically, the movable part 160L rotates in the R2 direction, causing the rod-shaped member 173L to move linearly backward, and the rod-shaped member 173L (rod-shaped part 173L1) moves to a non-restricted position described later, having moved out of (retracted from) any of the restricting parts 186L to 189L described later, thereby switching from the "removed restriction state" to the "restricted state". In this embodiment, the movable part 160L rotates in the R1 direction, causing the rod-shaped member 173L to move linearly forward, and the rod-shaped member 173L (rod-shaped part 173L1) moves to a restricted position described later, having entered any of the restricting parts 186L to 189L described later, thereby switching from the "removed restriction state" to the "restricted state".

[0070] Furthermore, in the state shown in Figure 7, the movable part 160L is biased in the R1 direction by the biasing part 165L, and therefore the hook 155L is pulled in the R1 direction by the movable part 160L. Consequently, even if vibration is applied to the slope mowing part 80L, it is possible to prevent the hook 155L from detaching from the bent part 166L of the movable part 160L.

[0071] Furthermore, although this embodiment illustrates a configuration in which the movable part 160L is connected to the fixed part 151L, the system is not limited to this configuration. Any configuration other than those described above is acceptable, as long as the movable part 160L can be gripped together with the fixed part 151L and the movable part 160L is movable relative to the fixed part 151L. Also, although this embodiment illustrates a configuration in which the movable part 160L is rotatably connected to the fixed part 151L, the system is not limited to this configuration. For example, the movable part 160L may be connected to the fixed part 151L so as to be translatably movable.

[0072] [5. Configuration and function of the tilt positioning member 180L] The configuration and function of the tilt positioning member 180L will be explained using Figure 8. Figure 8 is a rear view showing the configuration of the slope mowing unit 80L, the position adjustment mechanism 90L, and the tilt adjustment mechanism 130L. Figure 8(A) is a view of the slope mowing unit 80L, the position adjustment mechanism 90L, and the tilt adjustment mechanism 130L from the rear. For the sake of explanation, components such as the fixed part 151L and the movable part 160L have been omitted, and the rod-shaped part 173L1 of the rod-shaped member 173L is shown separately. In Figure 8, the slope mowing unit 80L rotates around the pivot axis 185L. Similarly, the rod-shaped part 173L1 (rod-shaped member 173L) also rotates around the pivot axis 185L, just like the slope mowing unit 80L. Furthermore, Figure 8(B) illustrates the positional relationship between the tilt positioning member 180L and the rod-shaped portion 173L1 in the state shown in Figure 8(A). Note that Figure 8 shows the state in which the mowing surface 204L is inclined at an angle θ1 with respect to the horizontal plane.

[0073] As described above, the tilt positioning member 180L is configured as a member with a roughly inverted U-shape, and the rear wall of the tilt positioning member 180L is flat, as shown in Figure 8. The tilt positioning member 180L is provided with a number of restricting sections 186L to 189L into which the rod-shaped section 173L1 can enter. The restricting sections 186L to 189L each restrict the range of motion of the rod-shaped section 173L1 (rod-shaped member 173L) relative to the tilt positioning member 180L, that is, the range of rotation of the slope mowing section 80L around the pivot axis 185L relative to the tilt positioning member 180L.

[0074] In this embodiment, the limiting portions 186L to 189L are each composed of recesses provided on the outer circumference of the tilting positioning member 180L. The range of motion of the rod-shaped portion 173L1 (rod-shaped member 173L) relative to the tilting positioning member 180L, that is, the range of rotation of the slope mowing portion 80L around the pivot axis 185L relative to the tilting positioning member, is limited by the rod-shaped portion 173L1 (rod-shaped member 173L) contacting the side walls of the limiting portions 186L to 189L (recesses). Of these side walls, those indicated by reference numerals in Figure 8(B) are called engaging portions 181L to 184L, 182'L, and 183'L. The rod-shaped portion 173L1 (rod-shaped member 173L) engages with any of these restricting portions 186L to 189L (more specifically, engaging portions 181L to 184L, 182'L, 183'L), thereby restricting the rotation of the slope mowing portion 80L by the tilt adjustment mechanism 130L.

[0075] Therefore, by retracting the rod-shaped portion 173L1 (rod-shaped member 173L) from any of the multiple limiting portions 186L to 189L (to the unrestricted position described later) and adjusting the inclination of the slope mowing portion 80L, the rotation range of the slope mowing portion 80L can be restricted to an adjusted predetermined rotation angle or a predetermined rotation angle range including the adjusted predetermined rotation angle. The "restricted state" shown in Figure 5, where the rod-shaped portion 173L1 (rod-shaped member 173L) is positioned in the restricted position described later, having entered the limiting portions 186L to 189L of the tilt positioning member 180L, is a state in which the rod-shaped portion 173L1 (rod-shaped member 173L) can engage with any of the engaging portions 181L to 184L, 182'L, or 183'L.

[0076] In Figure 5, the rod-shaped portion 173L1 (rod-shaped member 173L) has entered the limiting portion 186L of the tilting positioning member 180L, and therefore the rod-shaped member 173L can engage with the engaging portion 181L. On the other hand, in the "unrestricted state" shown in Figures 6 and 7, where the rod-shaped member 173L is retracted from the limiting portions 186L to 189L of the tilting positioning member 180L and is located in the unrestricted position described later, the rod-shaped portion 173L1 (rod-shaped member 173L) cannot engage with any of the limiting portions 186L to 189L (more specifically, the engaging portions 181L to 184L, 182'L, and 183'L). As described above, the switching operation between the "restricted state" and the "unrestricted state" is performed by rotating the movable portion 160L.

[0077] In this embodiment, the tilt positioning member 180L is provided with a plurality of limiting portions 186L to 189L (recesses), and the side walls of each recess function as engaging portions (engaging portions 181L to 184L, 182'L, 183'L). The rotation of the slope mowing portion 80L by the tilt adjustment mechanism 130L is restricted when the rod-shaped portion 173L1 (rod-shaped member 173L) comes into contact with (engages with) any of the engaging portions 181L to 184L, 182'L, or 183'L. In this state (a restricted state in which the rod-shaped portion 173L1 (rod-shaped member 173L) enters any of the restricting portions 186L to 189L), the rod-shaped portion 173L1 (rod-shaped member 173L) can engage with the engaging portions 181L to 184L, 182'L, and 183'L, so the position of this rod-shaped member 173L in the front-rear direction is sometimes called the "restricted position".

[0078] On the other hand, when the rod-shaped portion 173L1 (rod-shaped member 173L) tilts and is disengaged from (retracted from) the positioning member 180L, the rod-shaped portion 173L1 (rod-shaped member 173L) can no longer engage with any of the engaging portions 181L~184L, 182'L, or 183'L, allowing the slope mowing portion 80L to rotate freely. In this state (the unrestricted state in which the rod-shaped portion 173L1 (rod-shaped member 173L) is retracted from any of the restricting portions 186~189L), the position of the rod-shaped member 173L in the front-rear direction is sometimes referred to as the "unrestricted position".

[0079] The inclination of the engaging portions 182'L and 183'L is gentler than the inclination of the engaging portions 182L and 183L. In other words, the angle of the side wall of the recess (restricting portion 187L, 188L) with respect to the arc centered on the pivot axis 185L in the engaging portions 182'L and 183'L is smaller than the angle of the corresponding side wall in the engaging portions 182L and 183L.

[0080] Furthermore, the engaging portion is not limited to the side wall of the recess. For example, a configuration in which a projection functioning as an engaging portion is formed on the flat surface of a plate-shaped member that does not have a recess may be used instead of the tilting positioning member 180L. In this configuration, the space between the projections corresponds to the limiting portion. Also, in this embodiment, the tilting positioning member 180L may be any member provided with a limiting portion that corresponds to an engaging portion, and the portion on which the limiting portion is provided does not have to be flat. In addition, in this embodiment, a rod-shaped member 173L that moves in the front-rear direction is exemplified as a member that engages with the engaging portions 181L~184L, 182'L, and 183'L of the tilting positioning member 180L, but the configuration is not limited to this.

[0081] As shown in Figure 8, the rotation of the slope mowing section 80L in the R3 direction is restricted when the rod-shaped section 173L1 (rod-shaped member 173L) engages with the engaging section 182L, and the rotation of the slope mowing section 80L in the R4 direction is restricted when the rod-shaped section 173L1 (rod-shaped member 173L) engages with the engaging section 182'L. In the state shown in Figure 8, since the engaging section 182'L is provided in the R4 direction of the rod-shaped section 173L1 (rod-shaped member 173L), the rod-shaped section 173L1 (rod-shaped member 173L) can rotate between the engaging section 182'L (position shown by the dashed line) and the engaging section 182L (position shown by the solid line). In other words, the slope mowing section 80L can change from the inclination state shown by the solid line to the inclination state shown by the dashed line without being fixed at a constant inclination angle θ1. For example, the angle θ1 is approximately 30°.

[0082] The first gripping section 150L is located near the right end of the slope mowing section 80L, while the second gripping section 140L is located near its left end. In other words, the second gripping section 140L and the first gripping section 150L are located near both ends of the slope mowing section 80L in the left-right direction, facing each other (approximately), and the drive unit 83L is located between the second gripping section 140L and the first gripping section 150L. In a configuration in which the slope mowing section 80L moves up and down relative to the machine body 10, when adjusting the inclination of the slope mowing section 80L using the inclination adjustment mechanism 130L, the inclination may be adjusted while restricting the up-and-down movement of the slope mowing section 80L. In this case, according to the configuration of this embodiment, the operator can grasp the fixed part 151L and the movable part 160L, which are located near the rotation center of the slope mowing unit 80L around the pivot axis 185L, and rotate the movable part 160L in an intuitively easy-to-understand manner. This allows the operator to move the rod-shaped member 173L, which is in a restricted position, away from the restricting parts 186L to 189L of the tilting positioning member 180L. This releases the rotational restriction of the slope mowing unit 80L around the pivot axis 185L while restricting the vertical movement of the first gripping part 150L (the fixed part 151L and movable part 160L in the gripped state). As a result, the operator can move the rod-shaped member 173L from the restricted position to the unrestricted position with little force. Furthermore, by gripping the second gripping part 140L in that state and moving the gripping hand up and down, the slope mowing part 80L can be rotated around the pivot axis 185L, thereby adjusting the inclination of the slope mowing part 80L. In other words, the worker can use one hand to release the restriction on the rotation of the slope mowing part 80L around the pivot axis 185L and to restrict the up and down movement of the slope mowing part 80L on the pivot axis 185L side, and use the other hand to adjust the inclination of the slope mowing part 80L. Therefore, the work efficiency in the work of adjusting the inclination of the slope mowing part 80L can be improved. In addition, it is also possible for the worker to hold the first gripping part 150L (or the rod-shaped member 154L) and the second gripping part 140L and move the slope mowing part 80 up and down.

[0083] By the way, the lawnmower 100 of this embodiment is provided with a detection means 190 for detecting the operating state of the first gripping part 150 (operating means). Since the configuration of the detection means 190R is the same as that of the detection means 190L, we will focus on the detection means 190L in our explanation. As shown in Figures 5 to 7, the detection means 190L is located adjacent to the tilt adjustment mechanism 130L, and more specifically, on the outside (left side) of the pair of leg-shaped members 152L. The detection means 190L functions as a switch for detecting that the tilt adjustment mechanism 130L has entered an unlocked state. In other words, the detection means 190L functions as a switch for detecting the operating state of the first gripping part 150L. The detection means 190L has a movable contact 192L, a fixed contact 191L, a casing 193L, and an interlocking part 195L. The movable contact 192L has a detector 192L1 that protrudes forward from the casing 193L and is displaceable (bent) back and forth. The detector 192L1 is a leaf spring-shaped contact and includes an arc-shaped curved portion 192L1a that makes contact with the interlocking portion 195L, and a plate-shaped portion 192L1b that is connected to the curved portion 192L1a and makes contact with the fixed contact 191L. The movable contact 192L is electrically connected to a circuit board provided inside the casing 193L. The fixed contact 191L ​​is arranged to protrude forward from the front of the casing 193L so that it can make contact with the plate-shaped portion 192L1b of the movable contact 192L when it is displaced (bent) backward. The fixed contact 191L ​​is also electrically connected to a circuit board provided inside the casing 193L. Inside the casing 193L is a circuit board electrically connected to the movable contact 192L and the fixed contact 191L. The circuit board located inside the casing 193L is provided with terminals that allow the contact state, i.e., the conductive state, of the fixed contact 191L ​​and the movable contact 192 to be detected externally. Although not shown in the diagram, the circuit board located inside the casing 193L is electrically connected to the control unit 50 (electronic circuit board). The interlocking part 195L is an L-shaped member in plan view and includes a fixing part 195L2 that, together with the connecting part 171L, sandwiches and fixes the mounting part 173L2 of the rod-shaped member 173L, and a bending part 195L1 that bends outward (to the left) in front of the fixing part 195L2.A rod-shaped member 173L (mounting portion 173L2) is fixed to the inner (right) side of the front end of the fixing portion 195L2, and an elongated hole 196L, which is the same shape as the elongated hole of the connecting portion 171L, is provided on the rear end of the fixing portion 195L2. A pin 172L is inserted through the elongated hole 196L. The bent portion 195L1 is configured to be able to move in and out of contact with the curved portion 192L1a of the movable contact 192L by the forward and backward movement of the interlocking portion 195L.

[0084] As described above, the interlocking part 195L moves in the front-rear direction in conjunction with the restricted part 170L (rod-shaped member 173L). In other words, when the movable part 160L rotates in the R2 direction, i.e., upward, due to the operator's gripping operation, the interlocking part 195L moves backward together with the rod-shaped member 173L. When the interlocking part 195L moves backward, the bent part 195L1 of the interlocking part 195L comes into contact with the movable contact 192L at a predetermined position. After the bent part 195L1 and the movable contact 192L (curved part 192L1a) come into contact at a predetermined position, as the interlocking part 195L moves further backward, the movable contact 192L moves backward (bends) together with the interlocking part 195L, and as shown in Figure 6, the movable contact 192L (plate-shaped part 192L1b) comes into contact with the fixed contact 191L. As shown in Figure 6, when the rod-shaped portion 173L1 (rod-shaped member 173L) is in an unrestricted position, having moved out of any of the restricting portions 186L to 189L described later on the tilt positioning member 180L, the bent portion 195L1 of the interlocking portion 195L abuts against the movable contact 192L (curved portion 192L1a), and the movable contact 192L (plate-shaped portion 192L1b) abuts against the fixed contact 191L. Note that the state in which the movable contact 192L abuts against the fixed contact 191L ​​does not necessarily have to be the state in which the movable portion 160L and the fixed portion 151L are in contact.

[0085] On the other hand, when the movable part 160L rotates in the R1 direction relative to the fixed part 151L, i.e., downward, the restricted part 170L (rod-shaped member 173L) and the interlocking part 195L move forward in conjunction. When the bending part 195L1 of the interlocking part 195L reaches a predetermined position due to the forward movement of the interlocking part 195L, the bending part 195L1 becomes separated from the movable contact 192L (curved part 192L1a). As shown in Figure 5, when the rod-shaped portion 173L1 (rod-shaped member 173L) is in a restricted position where it is inserted into (entered) one of the restricting portions 186L to 189L of the tilt positioning member 180L, the bent portion 195L1 is separated from the movable contact 192L (curved portion 192L1a) and is not in contact with it, and the movable contact 192L (plate-shaped portion 192L1b) is separated from the fixed contact 191L ​​and is not in contact with it.

[0086] As will be explained in more detail later, when the control unit 50 detects that the movable contact 192L and the fixed contact 191L ​​have come into contact, it stops the drive of the drive unit 83L and stops the rotation of the blade unit 82. In other words, the movable contact 192L and the fixed contact 191L ​​function as switches that ensure the safety of the worker by detecting that the tilt adjustment mechanism 130L has been released due to the worker gripping the movable unit 160L together with the fixed unit 151L, or in other words, that the worker has operated the first gripping unit.

[0087] As shown in Figure 6 (with the worker gripping the movable part 160L together with the fixed part 151L), when the worker operates the hook 155L to hook it onto the movable part 160L and then releases gripping the movable part 160L, the biasing force of the biasing part 165L causes the movable part 160L to rotate in the R1 direction from the state shown in Figure 6. As described above, as the movable part 160L rotates in the R1 direction, the pin 172L slides against the side wall of the elongated hole 171L of the connecting part 171L and the elongated hole 196L of the interlocking part 195L, pushing the connecting part 171L and the interlocking part 195L forward, causing the restricted part 170L (rod-shaped member 173L) and the interlocking part 195L to move forward in conjunction. As shown in Figure 7, the hook 155L restricts the rotation of the movable part 160L in the R1 direction to a predetermined angle. In this state, the rod-shaped portion 173L1 (rod-shaped member 173L) is in an unrestricted position, having moved away from (retracted from) any of the restricting portions 186L to 189L described later on the tilt positioning member 180L, and the movable contact 192L (plate-shaped portion 192L1b) is separated from the fixed contact 191L ​​and does not come into contact with it, but the bent portion 195L1 remains in contact with the movable contact 192L (curved portion 192L1a).

[0088] [6. Control of the control unit 50] The control of the control unit 50 will be explained using Figures 5 to 9. Figure 9 is a functional block diagram showing the control system of a lawnmower according to one embodiment of the present invention.

[0089] The control unit 50 (electronic circuit board 520) is connected to the drive unit 54 of the travel unit 20 and the drive unit 83 of the slope mowing unit 80, and as described above, controls the drive unit 54 of the travel unit 20 and the drive unit 83 of the slope mowing unit 80. The control unit 50 (electronic circuit board 520) is also connected to the engine 60 that controls the drive of the drive unit 33 of the top surface mowing unit 30, and controls the engine 60 as well. Furthermore, the control unit 50 (electronic circuit board 520) is connected to a detection means 190 that detects the operating state of the first gripping unit 150L operated by the operator when adjusting the inclination of the slope mowing unit 80 relative to the machine body 10, and detects the state of the detection means 190 to control the drive unit 83 of the slope mowing unit 80. Details will be described later. In addition, the control unit 50 (electronic circuit board 520) is connected to a drive operation means 530 operated by the operator when driving the drive unit 83 of the slope mowing unit 80.

[0090] The drive operation means 530 is a means operated by the operator when driving the drive unit 83 (for example, the drive unit 83L). The drive operation means 530 is a push-button type switch provided on the control unit 50. However, the drive operation means 530 is not limited to a push-button type switch, and may be a key switch or a toggle switch. Furthermore, the drive operation means 530 may be provided on the machine body 10, on the slope mowing unit 80, or, if the operator can operate the grass cutter 100 by remote control or the like, the drive operation means 530 may be provided on the remote control.

[0091] This section will explain how the control unit 50 stops and restarts the drive unit 83. First, we will explain the control of the control unit 50 (stopping the drive unit 83) when an operator operates the first gripping unit 150 to adjust the inclination of the slope mowing unit 80 relative to the machine body 10.

[0092] When the worker grasps the movable part 160L together with the fixed part 151L from the state shown in Figure 5, the movable part 160L rotates in the R2 direction as described above, and as the movable part 160L rotates in the R2 direction, the interlocking part 195L moves backward in conjunction with it. When the interlocking part 195L moves backward, it comes into contact with the movable contact 192L. After the interlocking part 195L comes into contact with the movable contact 192L, the movable part 160L rotates further in the R2 direction, and the interlocking part 195L moves backward, causing the interlocking part 195L to move (bend) the movable contact 192L backward until it reaches the fixed contact 191L, resulting in the state shown in Figure 6.

[0093] When the control unit 50 detects that the movable contact 192L has come into contact with the fixed contact 191L, it stops supplying power (drive signal) to the drive unit 83L. As a result, the drive unit 83L stops driving, and the rotation of the blade 82 stops. In other words, the movable contact 192L and the fixed contact 191L ​​function as switches that ensure the safety of the worker, detecting that the tilt adjustment mechanism 130L has been released when the worker grips the movable part 160L together with the fixed part 151L. In other words, the control unit 50 can stop the drive of the drive unit 83L based on the operation of the first gripping part 150, which switches the tilt adjustment mechanism 130L from a "restricted state" to an "unrestricted state". As a result, the operator can adjust the inclination of the slope cutting unit 80L in a safe state with the rotation of the blade unit 82L stopped. Note that the state in which the drive unit 83L is stopped and the rotation of the blade unit 82 is stopped is sometimes referred to as the "stopped state".

[0094] Furthermore, in the state shown in Figure 6 (where the operator is gripping the movable part 160L together with the fixed part 151L), if the operator operates the hook 155L to hook it onto the movable part 160L, and then releases their grip on the movable part 160L (releasing their hand from the movable part 160L), as described above, the movable part 160L rotates by a predetermined angle in the R1 direction from the state shown in Figure 6 to the state shown in Figure 7. In the state shown in Figure 7, the movable contact 192L is separated from the fixed contact 191L. In this state, the operator is in the process of adjusting the inclination of the slope cutting unit 80L relative to the machine body 10, and it would be dangerous if the drive unit 83L were driven and the blade part 82 were rotated in this state. Therefore, when the control unit 50 detects that the movable contact 192L and the fixed contact 191L ​​have come into contact, it will not drive the drive unit 83L until the drive operation means 530 is operated. In other words, the drive unit 83L will not drive unless an operator restarts the drive of the drive unit 83L. The control unit 50 may choose not to detect the contact / separation state of the movable contact 192L and the fixed contact 191L ​​after detecting that they have come into contact, or it may choose not to drive the drive unit 83L even if it detects the separation between the movable contact 192L and the fixed contact 191L.

[0095] Next, we will explain how the operator restarts the drive unit 83L by operating the drive operation means 530.

[0096] After adjusting the inclination of the slope mowing unit 80 relative to the machine body 10, the operator operates the first gripping unit 150 to switch the inclination adjustment mechanism 130 from the unrestricted state to the restricted state. Then, the operator operates the drive operation means 530 to restart the drive unit 83. When the control unit 50 detects the operator's operation of the drive operation means 530, it supplies power to the drive unit 83L to drive the drive unit 83L and rotate the blade unit 82. As a result, the grass cutter 100 can move on the grass and perform grass cutting work. The control unit 50 may also detect the state of the detection means 190 (contact / separation of the movable contact 192 and the fixed contact 191) before driving the drive unit 83, and drive the drive unit 83 only if the movable contact 192 and the fixed contact 191 are separated.

[0097] In this embodiment, the detection means 190L is a switch operated by the interlocking part 195L (bending part 195L1), but the configuration is not limited to this. For example, it may be a contact sensor that detects when an operator touches it, or a proximity sensor that detects when an operator's hand approaches. When a contact sensor or proximity sensor is used for the detection means 190L, it is desirable that it be provided on at least one of the fixed part 151L or the movable part 160L, or on the second gripping part 140.

[0098] [7. Variation 1] Modification 1 of the lawnmower 100 shown in this embodiment will now be described. Modification 1 is a configuration in which a release operation means operated by the operator to release the aforementioned "stopped state" is added to the lawnmower 100. Modification 1 is effective for configurations such as a configuration in which the control unit 50 detects contact between the movable contact 192 and the fixed contact 191 and stops the drive of the drive unit 83, and then the control unit 50 does not perform any control; a configuration in which a switch or relay circuit is provided on the power supply line to the drive unit 83, and the control unit 50 detects contact between the movable contact 192L and the fixed contact 191L ​​and cuts off the switch or relay circuit on the power supply line to the drive unit 83; or a configuration in which the detection means 190 cuts off the switch or relay circuit on the power supply line to the drive unit 83 by contact between the movable contact 192L and the fixed contact 191L.

[0099] The release operation means is a means operated by the operator to release the "stopped state". Specifically, it is a means operated by the operator to release the aforementioned stop mode or to restore the aforementioned switches and relay circuits to a conductive state. In other words, after the control unit 50 stops driving the drive unit 83 based on the detection means 190 detecting the operator's operation to adjust the tilt of the slope mowing unit 80 relative to the machine body 10, the drive unit 83 will not drive even if the drive operation means 530 is operated until the operator operates the release operation means.

[0100] The release operation means, like the drive operation means 530, is a push-button type switch provided on the control unit 50 (not shown in the figure). Furthermore, the release operation means is not limited to a push-button type switch, like the drive operation means 530; it may be a key switch or a toggle switch. The release operation means may be provided on the machine body 10, on the slope mowing unit 80, or, if the operator can operate the mower 100 using a remote control, the release operation means may be provided on the remote control. The release operation means is electrically connected to the control unit 50 (electronic circuit board 520).

[0101] After adjusting the inclination of the slope mowing unit 80 relative to the machine body 10, the operator operates the first gripping unit 150 to switch the inclination adjustment mechanism 130 from the unrestricted state to the restricted state. The operator operates the release operation means to restart the drive unit 83. When the control unit 50 detects that the operator has operated the release operation means, it releases the aforementioned stop mode and restores the disconnected switches and relay circuits to a conductive state. Subsequently, the operator operates the drive operation means 530 to restart the drive unit 83. When the control unit 50 detects that the operator has operated the drive operation means 530, it drives the drive unit 83L and rotates the blade unit 82. As a result, the grass cutter 100 can move on the grass and perform grass cutting work. The control unit 50 may, before driving the drive unit 83, detect the state of the detection means 190 (contact / separation of the movable contact 192 and the fixed contact 191), and only drive the drive unit 83 if the movable contact 192 and the fixed contact 191 are separated.

[0102] [8. Variation 2] A second modification of the lawnmower 100 shown in this embodiment will now be described. In modification 1, two operating means, a release operating means and a drive operating means 530, were required to restart the drive of the drive unit 83 after adjusting the inclination of the slope mowing unit 80 relative to the machine body 10. In modification 2, the stopped state is released and the drive of the drive unit 83 is restarted with a single operating means. Modification 2 is configured to have a release / restart operating means that is operated by the operator to release the aforementioned stopped state and restart the drive of the drive unit 83, instead of the release operating means of modification 1. Furthermore, Modification 2 is effective for configurations similar to Modification 1, such as a configuration in which the control unit 50 detects contact between the movable contact 192 and the fixed contact 191, stops the drive of the drive unit 83, and then has a stop mode in which the control unit 50 does not perform any control; a configuration in which a switch or relay circuit is provided on the power supply line to the drive unit 83, and the control unit 50 detects contact between the movable contact 192L and the fixed contact 191L ​​and shuts off the switch or relay circuit on the power supply line to the drive unit 83; and a configuration in which the detection means 190 shuts off the switch or relay circuit on the power supply line to the drive unit 83 by the contact between the movable contact 192L and the fixed contact 191L.

[0103] The release / restart operation means is a means operated by the operator to release the "stopped state" and restart the drive of the drive unit 83. Specifically, it is a means operated by the operator to release the aforementioned stopped mode, restore the aforementioned switches and relay circuits to a conductive state, and restart the drive of the drive unit 83. In other words, after the control unit 50 stops the drive of the drive unit 83 based on the detection means 190 detecting the operator's operation to adjust the tilt of the slope mowing unit 80 relative to the machine body 10, the drive unit 83 will not drive until the operator operates the release / restart operation means.

[0104] The release / restart operation means, like the drive operation means 530 and the release operation means, is a push-button type switch provided on the control unit 50, although it is not shown in the figures. Furthermore, the release / restart operation means is not limited to a push-button type switch, like the drive operation means 530 and the release operation means, but may be a key switch or a toggle switch. In addition, the release / restart operation means may be provided on the machine body 10, on the slope mowing unit 80, or, if the operator can operate the grass mower 100 by remote control, the release / restart operation means may be provided on the remote control. The release / restart operation means is electrically connected to the control unit 50 (electronic circuit board 520).

[0105] After adjusting the inclination of the slope mowing unit 80 relative to the machine body 10, the operator operates the first gripping unit 150 to switch the inclination adjustment mechanism 130 from the unrestricted state to the restricted state. The operator operates the release / restart operation means to restart the drive unit 83. When the control unit 50 detects that the operator has operated the release / restart operation means, it releases the aforementioned stop mode, restores the disconnected switches and relay circuits to a conductive state, and then drives the drive unit 83L to rotate the blade unit 82. As a result, the grass cutter 100 can move on the grass and perform grass cutting work. The control unit 50 may also detect the state of the detection means 190 (contact / separation of the movable contact 192 and the fixed contact 191) before driving the drive unit 83, and drive the drive unit 83 only if the movable contact 192 and the fixed contact 191 are separated.

[0106] In the above embodiment, a configuration in which the working section, the slope mowing section 80L, is provided on a self-propelled lawnmower 100 was illustrated, but the configuration is not limited to this. For example, the above configuration may be applied to a work implement that can be attached to and detached from a mobile machine such as a tractor.

[0107] Although the present invention has been described above with reference to the drawings, the present invention is not limited to the embodiments described above, and can be modified as appropriate without departing from the spirit of the invention. For example, an agricultural machine based on this embodiment, with additions, deletions, or design changes made by a person skilled in the art, is also included in the scope of the present invention as long as it retains the gist of the invention. Furthermore, the embodiments described above can be combined as appropriate as long as they do not contradict each other, and technical matters common to each embodiment are included in each embodiment even without explicit description.

[0108] Furthermore, any effects or benefits other than those brought about by the embodiments described above, if they are clear from the description herein or easily predictable to a person skilled in the art, are naturally considered to be brought about by the present invention. [Explanation of symbols]

[0109] 10: Machine body, 11: Mounting member, 14: Machine body, 15: Support case, 17: Mounting member, 17L: Mounting member, 20: Running section, 20L: Running section, 20R: Running section, 21L: Crawler belt, 22L: Drive wheel, 23L: Drive wheel, 24: Crawler frame, 24L: Crawler frame, 30: Top surface mowing section, 31: Casing, 32: Blade section, 32L: Blade section, 32R: Blade section, 33: Drive unit, 33L: Drive unit, 33R: Drive unit, 40: Battery, 50: Control unit, 54: Drive unit, 54L: Drive unit, 60: Engine, 70: Alternator, 80: Slope mowing section, 80L: Slope 80R:Slope mowing section, 81:Casing, 81L:Casing, 81R:Casing, 82:Blade section, 82L:Blade section, 82R:Blade section, 83:Drive unit, 83L:Drive unit, 83R:Drive unit, 90:Position adjustment mechanism, 90L:Position adjustment mechanism, 90R:Position adjustment mechanism, 100:Grass cutter, 110:Centerline, 120:Cutting section, 130:Tilt adjustment mechanism, 130L:Tilt adjustment mechanism, 130R:Tilt adjustment mechanism, 140:Second gripping section, 140L:Second gripping section, 140R:Second gripping section, 150:First gripping section, 150L:First gripping section, 151L:Fixing section, 152L: Leg-shaped member, 153L: Plate, 154L: Rod-shaped member, 155L: Hook, 160: Movable part, 160L: Movable part, 161L: First arm part, 162L: Second arm part, 164L: Rotating shaft, 165L: Biasing part, 166L: Bending part, 170: Restricted part, 170L: Restricted part, 171L: Connecting part, 172L: Pin, 173L: Rod-shaped member, 173L1: Rod-shaped part, 173L2: Mounting part, 175L: Connection part, 176L: Reinforcement member, 177L: Through hole, 180L: Inclined positioning member, 181L: Engaging part, 182'L: Engaging part, 182L: Engaging part, 183'L: Engaging part, 1 83L: Engaging part, 184L: Engaging part, 185L: Rotating shaft, 186L: Restricting part, 187L: Restricting part, 188L: Restricting part, 189L: Restricting part, 190: Detection means, 190L: Detection means, 191: Fixed contact, 191L: Fixed contact, 192: Movable contact, 192L: Movable contact, 192L1: Detector, 192L1a: Curved part, 192L1b: Plate-shaped part, 193L: Casing, 195L: Interlocking part, 195L1: Bent part, 195L2: Fixed part, 196L: Elongated hole, 200: Ridge, 201: Top surface, 202: Slope, 203: Horizontal surface, 204: Mowing surface, 204L: Mowing surface, 206: Plane,300: Anti-tipping means, 300L: Anti-tipping means, 300R: Anti-tipping means, 310: Support frame, 320: Main arm, 330: Auxiliary arm, 400: Adjustment part, 400L: Adjustment part, 400R: Adjustment part, 410: Roller, 410L: Roller, 410R: Roller, 420: Roller support part, 420L: Roller support part, 420R: Roller support part, 520: Electronic circuit board, 530: Drive operation means, 901L: Fixing part,

Claims

1. The aircraft and, A cutting unit having a cutting blade and a drive unit that rotates the cutting blade, and the cutting unit having an adjustable tilt relative to the machine body, The system comprises a control unit for controlling the drive unit, The harvesting unit has an operating means that the operator uses to adjust the inclination of the harvesting unit relative to the machine body. The control unit stops the drive of the drive unit based on an operation on the operating means of the lawnmower.

2. The drive unit is equipped with a drive operation means operated by an operator, The lawnmower according to claim 1, wherein the control unit stops driving the drive unit based on an operation on the operating means, and does not drive the drive unit until the drive operating means is operated.

3. The cutting section is equipped with a tilt adjustment mechanism that can adjust the tilt of the cutting section relative to the machine body, The tilt adjustment mechanism can be switched between a restricted state in which the tilt adjustment is limited and an unrestricted state in which the tilt adjustment is released by the operator's operation of the operating means. The lawnmower according to claim 1 or 2, wherein the control unit stops the drive of the drive unit based on an operation on the operating means that switches from the restricted state to the unrestricted state.

4. The tilt adjustment mechanism is, A fixing part fixed to the cutting part, It comprises a movable part that is provided so as to be grippable together with the fixed part and is movable relative to the fixed part, The movable part is movable relative to the fixed part by being grasped by the worker together with the fixed part. The movement of the movable part relative to the fixed part switches from the restricted state to the unrestricted state. The lawnmower according to claim 3.

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