JP7632333B2 - Grass trimmer - Google Patents

Description

The present invention relates to a lawnmower.

Patent document 1 discloses a lawnmower that can be operated automatically or remotely.

JP 2018-174707 A

However, the lawnmower described in Patent Document 1 above is unable to cut grass that has fallen due to being bent or otherwise damaged, and there is room for improvement.

The present invention aims to provide a lawnmower that can cut fallen grass.

The grass mower of claim 1 has a main body provided with a moving mechanism, a rotating member rotatably mounted on the main body with the vertical direction as the thickness direction , and a cutting blade unit including a cutting blade attached to the outer peripheral end of the rotating member , and a suction force generating mechanism provided on the main body for generating an upward suction force near the cutting blade unit, the suction force generating mechanism being constituted by a rotating blade-shaped cutout formed in the rotating member, and a first inclined portion formed in the rotating member, the opening edge on the opposite side to the direction of rotation of the cutout being provided with a first inclined portion that inclines in the opposite direction to the direction of rotation as it moves from the bottom to the top, and the opening edge on the rotation direction side of the cutout being provided with a second inclined portion that inclines in the opposite direction to the direction of rotation as it moves from the bottom to the top.

In the grass cutter according to claim 1, the cutting blade unit is rotatably mounted on the main body. The main body is also equipped with a movement mechanism, so that grass around the main body can be cut by rotating the cutting blade unit while moving the main body with the movement mechanism.

The main body is also provided with a suction force generating mechanism that generates an upward suction force in the vicinity of the cutting blade unit, which makes it possible to lift up grass that has fallen around the cutting blade unit and cut the fallen grass.
Furthermore, the rotating member has a notch shaped like a rotating blade. This allows the blade to cut grass while generating an upward suction force by rotating the rotating member. In other words, there is no need to provide a separate fan or other component.

The grass cutter according to claim 2 is the same as claim 1, except that a cover is provided around the cutting blade unit, extending in the vertical direction, to prevent foreign objects from entering the cutting blade unit.

In the grass cutter according to claim 2, the cover can prevent foreign objects such as pebbles from entering the cutting blade unit, and the cutting blade can be effectively protected. Even if the grass is knocked down by the cover, the suction force generating mechanism can raise the grass up, so the grass can be cut efficiently while protecting the cutting blade.

A grass mower according to a third aspect of the present invention is the grass mower according to the first or second aspect, further comprising a storage section above the suction force generating mechanism, capable of storing grass sucked by the suction force generating mechanism.

In the grass cutter according to claim 3 , the grass cut by the cutting blade unit can be sucked up by the suction generating mechanism and stored in the storage section. This makes it possible to prevent the cut grass from scattering around. In addition, by using the suction generating mechanism to stand up fallen grass, a dedicated part for sucking in the cut grass is not required.

As described above, the mower according to the present invention can cut fallen grass.

1 is a perspective view showing a grass mower according to a first embodiment. FIG. 1 is a side cross-sectional view showing a grass mower according to a first embodiment in a partially broken state as viewed from the side; 1 is a block diagram showing a hardware configuration of a grass mower according to a first embodiment. FIG. FIG. 3 is an enlarged view of a main part of FIG. 2 . FIG. 11 is a closed cross-sectional view of a cutting blade unit constituting a grass mower according to a second embodiment, as viewed from above.

First Embodiment
A mower 10 according to a first embodiment will be described with reference to the drawings. Note that the arrows UP, FR, and RH in the drawings respectively indicate the upper side in the up-down direction, the front side in the front-rear direction, and the right side in the left-right direction of the mower 10. Also, since the mower 10 is configured to be movable in both the front and rear directions, the forward direction does not necessarily coincide with the traveling direction.

As shown in Figures 1 and 2, the grass cutter 10 of this embodiment is mainly composed of a main body 12, a cutting blade unit 14, and a control unit 16.

(Main body portion 12)
The main body 12 is formed in a generally rectangular parallelepiped shape with an open bottom, and is provided with crawler units 18 as a movement mechanism on the main body 12. The crawler units 18 are provided on both the left and right sides of the front end of the main body 12 and on both the left and right sides of the rear end.

Each crawler section 18 is composed of a rubber crawler 18A, a drive wheel 18B, a first idler wheel 18C, and a second idler wheel 18D. The rubber crawler 18A is formed in an endless belt shape and is wrapped around the drive wheel 18B, the first idler wheel 18C, and the second idler wheel 18D.

The drive wheel 18B is connected to a drive motor 52 (see FIG. 3) disposed inside the main body 12 via a rotating shaft (not shown). The drive motor 52 is configured to receive power from a battery (not shown). When power is supplied to operate the drive motor 52, the drive wheel 18B rotates and the rubber crawler 18A moves in a unidirectional circular motion.

The first idler wheel 18C is disposed forward and below the drive wheel 18B, and is rotatably attached to a rotating shaft (not shown) that extends in the left-right direction. The first idler wheel 18C rotates following the movement of the rubber crawler 18A. The second idler wheel 18D is disposed rearward of the first idler wheel 18C, and is rotatably attached to a rotating shaft (not shown) that extends in the left-right direction. The second idler wheel 18D rotates following the movement of the rubber crawler 18A.

Here, a drive motor 52 is provided independently for each of the four crawler units 18, and by controlling the four drive motors 52, it is possible to move the grass cutter 10 in any direction. Note that, for ease of explanation, in FIG. 3, the four drive motors 52 are illustrated together.

A cover 20 is provided on the front of the main body 12. The cover 20 is a generally flat plate-shaped member with its thickness direction in the front-to-rear direction, and extends in the vertical and horizontal directions. The bottom end of the cover 20 is located lower than the bottom end of the main body 12, and the cover 20 narrows the gap between the main body 12 and the ground. This cover 20 prevents foreign objects such as stones from entering the cutting blade unit 14, which will be described later.

In this embodiment, as an example, the cover 20 is provided only on the front surface of the main body 12, but this is not limited to this. For example, a similar cover 20 may also be provided on the rear and side surfaces of the main body 12. Also, a member for preventing the intrusion of foreign objects similar to the cover 20 may be provided on both side surfaces of the main body 12.

(Cutting blade unit 14)
2, the cutting blade unit 14 is provided inside the main body 12. The cutting blade unit 14 includes a rotating member 22, a cutting blade 24, a rotating shaft 26, and a cutting blade motor 28.

The rotating member 22 is disposed near the lower opening 12A of the main body 12 with the plate thickness direction being the up-down direction. The rotating member 22 is also fixed to a rotating shaft 26 (described later) and is configured to be rotatable together with the rotating shaft 26 with respect to the main body 12.

The rotating member 22 is provided with a plurality of cutting blades 24. The cutting blades 24 are attached to the outer peripheral end of the rotating member 22, and in this embodiment, as an example, four cutting blades 24 are provided at equal intervals along the circumferential direction of the rotating member 22.

Each cutting blade 24 is made of a thin metal material with its thickness direction extending vertically, and is configured to be able to cut grass.

The rotating shaft 26 is disposed in the center of the main body 12 and extends in the vertical direction, and the rotating member 22 is attached to the lower end of the rotating shaft 26. The upper end of the rotating shaft 26 is connected to the blade motor 28.

The blade motor 28 is attached to the top of the main body 12 and is driven by power supplied from a battery (not shown) provided in the main body 12. The blade motor 28 also has an output shaft (not shown), and this output shaft is connected to the rotating shaft 26 via a gear or pulley (not shown). Therefore, when the blade motor 28 is driven, a rotational force is transmitted to the rotating member 22 via the rotating shaft 26, and the rotating member 22 rotates in one direction around the rotating shaft 26.

Here, a fan 30 that constitutes a suction force generating mechanism is attached to the rotating shaft 26. Details of the fan 30 will be described later.

As shown in Figures 1 and 2, the control unit 16 is provided on the upper surface of the main body 12 and has a substantially rectangular parallelepiped housing 16A.

A GPS (Global Positioning System) device 32 is attached to the top surface of the housing 16A. The GPS device 32 is a device that measures the current position of the grass cutter 10, and includes an antenna (not shown) that receives signals from GPS satellites.

A camera unit 34 is attached to the front of the housing 16A. The camera unit 34 is a unit made up of a combination of multiple cameras, and is capable of capturing images of the situation around the grass cutter 10. The control unit 16 is also provided with a controller 36, which is a control unit.

(Hardware configuration of the grass mower 10)
Fig. 3 is a block diagram showing the hardware configuration of the grass mower 10. As shown in Fig. 3, a controller 36 constituting the grass mower 10 is configured to include a CPU (Central Processing Unit: processor) 38, a ROM (Read Only Memory) 40, a RAM (Random Access Memory) 42, a storage 44, a communication I/F (communication interface) 46, and an input/output I/F (input/output interface) 48. Each component is connected to each other via a bus 50 so as to be able to communicate with each other.

The CPU 38 is a central processing unit that executes various programs and controls each part. That is, the CPU 38 reads the programs from the ROM 40 or storage 44, and executes the programs using the RAM 42 as a working area. The CPU 38 also controls each of the above components and performs various calculation processes according to the programs recorded in the ROM 40 or storage 44.

The ROM 40 stores various programs and various data. The RAM 42 is a non-temporary recording medium that temporarily stores programs or data as a working area. The storage 44 is a non-temporary recording medium that is configured with a HDD (Hard Disk Drive) or SSD (Solid State Drive) and stores various programs including an operating system and various data. In this embodiment, the storage 44 stores the automatic driving program and various data of the grass mower 10.

The communication I/F 46 is an interface that allows the lawnmower 10 to communicate with other devices, and uses standards such as CAN (Controller Area Network), Ethernet (registered trademark), LTE (Long Term Evolution), FDDI (Fiber Distributed Data Interface), and Wi-Fi (registered trademark).

The input/output I/F 48 is electrically connected to the GPS device 32, the camera unit 34, the drive motor 52, the blade motor 28, and the fan 30. The controller 36 controls the drive motor 52 based on the surrounding images detected by the camera unit 34 and information such as the current position of the lawnmower 10 acquired by the GPS device 32, thereby causing the lawnmower 10 to automatically travel.

The controller 36 may also automatically drive the grass mower 10 based on a driving plan for the grass mower 10 acquired from an external source and the remaining battery charge (not shown).

(Fan 30)
2, the fan 30 is attached to the rotating shaft 26. Specifically, the fan 30 includes four rotating blades 30A, and each of the rotating blades 30A is fixed to the rotating shaft 26.

The rotating blade 30A is shaped to generate an airflow from the bottom to the top when the blade motor 28 is driven. Therefore, when the blade motor 28 is driven, the rotating member 22 and the fan 30 rotate in one direction, generating an upward suction force near the blade unit 14.

(Action)
Next, the operation of this embodiment will be described.

In the grass cutter 10 according to this embodiment, the grass around the main body 12 can be cut by rotating the cutting blade unit 14 while moving the main body 12 using the crawler unit 18, which is a movement mechanism.

The main body 12 is also provided with a fan 30, which is a suction force generating mechanism. When this fan 30 is activated, an upward suction force is generated near the cutting blade unit 14. This allows grass that has fallen around the cutting blade unit 14 to be lifted up, and the fallen grass can also be cut.

This action will be explained with reference to Figure 4. As shown in Figure 4, when cutting grass G while moving the mower 10, the cover 20 provided on the front side of the main body 12 can prevent foreign objects such as pebbles from entering the inside of the main body 12. This can effectively protect the cutting blade 24.

Here, if the grass G is relatively long, it will come into contact with the cover 20 and bend the grass G in the direction of travel of the mower 10. Then, the grass G that has entered the inside of the main body 12 will be sucked upward by the airflow generated by the operation of the fan 30, and will be raised up.

In this way, even when the cover 20 is provided, the grass G can be cut by the cutting blade 24 while the grass G is raised. In other words, the grass G can be cut efficiently while protecting the cutting blade 24. In particular, because the fan 30 is provided above the cutting blade unit 14, the grass around the cutting blade unit 14 can be effectively raised by operating the fan 30.

In addition, in this embodiment, the fan 30 is attached to the same rotating shaft 26 as the rotating member 22, so that by simply driving the blade motor 28, the rotating member 22 can be rotated while generating an upward suction force. As a result, there is no need to provide a dedicated motor for operating the fan 30, and an increase in the number of parts can be suppressed. In addition, power consumption can be reduced compared to when a separate motor is operated, and the operating time of the grass cutter 10 can be secured for a long time.

Second Embodiment
Next, a mower 60 according to a second embodiment will be described. The same components as those in the first embodiment are given the same reference numerals, and the description thereof will be omitted as appropriate. The mower 60 according to this embodiment has the same configuration as the first embodiment, except that the fan 30 is not provided and the cutting blade unit 62 is different.

As shown in FIG. 5, the blade unit 62 constituting the grass cutter 60 according to this embodiment includes a rotating member 64 and a blade 66. The rotating member 64 holds the blade 66 and is fixed to the rotating shaft 26. The rotating shaft 26 is connected to the blade motor 28 as in the first embodiment (see FIG. 2). Therefore, when the blade motor 28 is driven, a rotational force is transmitted to the rotating member 64 via the rotating shaft 26, and the rotating member 64 rotates in one direction around the rotating shaft 26. The arrow in the figure indicates the rotation direction of the rotating member 64.

The cutting blade 66, like the cutting blade 24 of the first embodiment, is made of a thin metal member with its thickness direction in the vertical direction, and is configured to be able to cut grass. In addition, four cutting blades 66 are provided at equal intervals along the circumferential direction of the rotating member 64, and each cutting blade 66 is attached to the outer peripheral end of the rotating member 64.

The rotating member 64 is disposed near the opening 12A on the lower side of the main body 12 with the plate thickness direction being the up-down direction (see FIG. 2). The rotating member 64 is also formed with a number of notches 64A. Each of the notches 64A is formed in a rotating blade shape similar to that of a fan. A first inclined portion 64B and a second inclined portion 64C are provided on the opening edge of the notches 64A.

The first inclined portion 64B is provided on the opening edge of the cutout portion 64A on the side opposite the direction of rotation, and is inclined in the opposite direction to the direction of rotation from the bottom to the top. In other words, the opening width of the cutout portion 64A is inclined so as to increase from the bottom to the top.

The second inclined portion 64C is provided on the opening edge of the cutout portion 64A on the rotational direction side, and is inclined in the opposite direction to the rotational direction as it goes from the bottom to the top. In other words, the opening width of the cutout portion 64A is inclined so as to narrow as it goes from the bottom to the top.

Since the first inclined portion 64B and the second inclined portion 64C are formed as described above, by rotating the rotating member 64 in the direction of the arrow in the figure, an airflow is generated that flows from the bottom to the top through the cutout portion 64A.

(Action)
Next, the operation of this embodiment will be described.

In the grass cutter 60 according to this embodiment, the rotating member 64 is formed with a blade-shaped notch 64A, so that by rotating the rotating member 64, the cutting blade 66 can cut the grass G while generating an upward suction force. In other words, there is no need to provide a separate fan or other component. Other functions are the same as those of the first embodiment.

The above describes the mowers 10 and 60 according to the first and second embodiments, but it goes without saying that the present invention can be embodied in various forms without departing from the spirit of the invention. For example, in the above embodiment, the grass G cut by the mowers 10 and 60 is left as it is, but the mowers 10 and 60 may be provided with a storage section to store the cut grass G.

A case where a storage section is added to the grass cutter 10 shown in Figure 2 will be described. In this case, a duct connection hole may be formed on the top surface of the main body 12 to connect one end of the duct, and a box-shaped storage section may be attached to the other end of the duct. If an exhaust hole is formed in the storage section, the airflow generated by the fan 30 flowing upward through the duct into the storage section and is discharged from the exhaust hole formed in the storage section. Also, grass G cut by the cutting blade unit 14 is sent from the duct to the storage section together with the airflow. If the exhaust hole is formed large enough that the grass G cannot pass through, only the cut grass G will be stored in the storage section.

In a structure with a storage section as described above, the cut grass G is automatically stored in the storage section, eliminating the need to dispose of the cut grass G all at once. In addition, the grass G is stored using the fan 30 that constitutes the suction force generating mechanism, eliminating the need for a dedicated suction unit, etc.

In addition, in the above embodiment, the camera unit 34 is provided only on the front surface of the control unit 16, but this is not limited to the above. For example, similar camera units 34 may also be provided on the rear and side surfaces of the control unit 16 to capture images of the surroundings of the mower 10. In addition to the camera unit 34, sensors capable of detecting the surrounding environment may also be provided.

In addition, in the first embodiment, the suction force generating mechanism is configured with one fan 30, but this is not limited to the above. For example, multiple fans may be provided inside the main body 12. In this case, the direction and magnitude of the suction force can be controlled compared to a configuration in which suction force is generated by one fan. In addition, the fan does not need to be attached to the rotation shaft 26 of the rotating member 22, and a separate fan rotation shaft may be provided.

Furthermore, in the second embodiment, the rotating member 64 is formed with the notch 64A in the shape of a rotating blade, but this is not limited to this. For example, the rotating member itself may be formed in a rotating blade shape. In this case, the cutting blade 66 is attached to the outer peripheral end of the rotating member in the shape of a rotating blade.

The shape and number of the cutting blades 24, 66 are not particularly limited, and the number of cutting blades may be three or less. Conversely, the number of cutting blades may be five or more. Furthermore, a configuration in which multiple rotating members 22, 64 are provided may be used.

In addition, in the above embodiment, a crawler unit 18 is provided as a movement mechanism, but this is not limited to this. For example, a configuration in which multiple wheels are provided instead of the crawler unit, or other movement mechanisms may be adopted.

Furthermore, in the above embodiment, a generally flat cover 20 with the thickness direction being in the front-to-rear direction is provided, but this is not limited thereto, and the cover may have another shape. Also, a configuration in which the main body and the cover are integrated may be adopted. In this case, the cover becomes part of the main body.

10 Grass cutter 12 Main body 14 Cutting blade unit 18 Crawler unit (moving mechanism)
20 Cover 22 Rotating member 24 Cutting blade 30 Fan (suction force generating mechanism)
60 Grass cutter 62 Cutting blade unit 64 Rotating member 64A Notch 66 Cutting blade

Claims (3)

A main body portion including a moving mechanism;
a blade unit including a rotating member rotatably provided on the main body with the up-down direction being the plate thickness direction , and a blade attached to an outer peripheral end of the rotating member ;
a suction force generating mechanism provided in the main body portion and configured to generate an upward suction force in the vicinity of the cutting blade unit;
having
the suction force generating mechanism is configured by a rotating blade-shaped notch formed in the rotating member,
A first inclined portion is provided on the opening edge opposite the direction of rotation in the cutout portion, the first inclined portion inclining in the opposite direction to the direction of rotation as it moves from the bottom to the top, and a second inclined portion is provided on the opening edge on the rotation direction side in the cutout portion, the second inclined portion inclining in the opposite direction to the direction of rotation as it moves from the bottom to the top . The mower according to claim 1, further comprising a cover extending in the vertical direction around the cutting blade unit to prevent foreign objects from entering the cutting blade unit. 3. The grass mower according to claim 1, further comprising a storage section above the suction force generating mechanism, the storage section being capable of storing grass sucked by the suction force generating mechanism .