JP4863728B2 - lawn mower - Google Patents

Description

  The present invention relates to a lawn mower used for lawn mowing work.

  Japanese Patent Laid-Open No. 2003-117267 (Patent Document 1) discloses a technique related to a trimming machine that can be applied to hedge trimming work and lawn trimming work. The trimming machine described in the above publication is a double-edged drive type that drives both an upper blade and a lower blade that are arranged one above the other, and a blade unit for hedges used for hedge cutting work, And a lawn blade unit used for mowing. In other words, the hedge blade unit and the lawn blade unit are exchanged to replace the hedge blade unit with the lawn blade unit.

In the above-described mower, when performing lawn mowing work using a blade unit for lawn, that is, when used as a lawn mower, it is a double-blade drive type that drives both the upper and lower blades. When mowing the lawn around the fixed object, the upper blade or the lower blade interferes with the fixed object, and it is difficult to cut the area around the fixed object. On the other hand, in the case of a single blade drive type in which the lower blade of the upper blade and the lower blade is fixed and only the upper blade is driven, the fixed lower blade is used as a guide member and trimmed while moving along the fixed object. Since the work can be performed, the pruning work can be easily performed.
JP 2003-117267 A

  The present invention has been made in view of the above points, and provides a technique capable of rationally switching between a double-blade drive mode and a single-blade drive mode for a blade driving mode in a lawn mower. With the goal.

In order to achieve the above object, the invention described in each claim is configured.
The lawn mower according to the first aspect of the present invention includes a main body portion, a blade mounting portion, a blade assembly, an upper blade driving member, and a lower blade driving member. The blade mounting portion has a blade mounting surface formed substantially horizontally in the lower region of the main body portion. The blade assembly includes a base plate, an upper blade and a lower blade that are arranged above and below so as to overlap each other on the upper surface of the base plate, and a connecting shaft that connects the upper blade and the lower blade to the base plate so as to be horizontally swingable. And is detachably attached to the blade mounting portion. The upper blade driving member drives the upper blade by rotating while engaged with the upper blade. The lower blade driving member drives the lower blade opposite to the upper blade by rotating while engaged with the lower blade. The lawn mower according to the present invention uses the upper blade driving member by maintaining the engagement between the upper blade driving member and the upper blade for the driving modes of the upper blade and the lower blade by the upper blade driving member and the lower blade driving member. A double-blade drive mode that allows the lower blade to be driven by the lower blade drive member by allowing the upper blade to be driven and maintaining the engagement between the lower blade drive member and the lower blade, and the upper blade drive member and the upper blade The upper blade can be driven by the upper blade driving member by maintaining the engagement with the blade, and the lower blade can be driven by the lower blade driving member by releasing the engagement between the lower blade driving member and the lower blade. It is possible to switch between prohibited single-blade drive modes. As the “upper blade driving member” and “lower blade driving member” in the present invention, an eccentric cam (disk cam) is typically used. However, the cam is not limited to the eccentric cam, and is driven by a heart cam, a tangential cam, a yoke cam, or the like. It is possible to suitably use a flat cam in which a portion engaged with the upper blade or the lower blade on the side operates in a plane. In the present invention, the term “drive oppositely” refers to a mode in which the lower blade is driven in an opposite phase with respect to the operation direction of the upper blade.

According to the present invention, there is further provided a drive mode switching member for switching the drive mode of the upper blade and the lower blade by the upper blade drive member and the lower blade drive member between the double blade drive mode and the single blade drive mode. The drive mode switching member is placed on the lower surface of the base plate, and the first position switches the drive mode to the double-blade drive mode, and the second position is placed on the upper surface of the base plate to switch the drive mode to the single-blade drive mode. The position can be changed between. Note that the “position change” in the present invention is preferably either an aspect in which the position can be changed while the drive mode switching member is connected to the base plate, or an aspect in which the position can be changed while being disconnected from the base plate. Included. The position of the drive mode switching member is changed in a state where the blade assembly is removed from the blade mounting portion.In this case, the blade assembly is removed in a state where it is completely separated from the blade mounting portion, or Any of removal in a state where a part is connected to the blade mounting portion is preferably included.
When the drive mode switching member is placed at the first position, the mounting height position in the vertical direction with respect to the blade mounting portion of the blade assembly is set to the upper position. This upper position is typically realized by the upper surface of the base plate directly contacting the blade mounting surface. Thus, the engagement state between the upper blade driving member and the upper blade and the engagement state between the lower blade driving member and the lower blade are maintained, respectively, and the upper blade and the lower blade are driven by the upper blade driving member and the lower blade driving member. Further, since the drive mode switching member does not interfere with either the upper blade or the lower blade, the horizontal swing operation of the upper blade and the lower blade is allowed.
On the other hand, when the drive mode switching member is placed at the second position, the drive mode switching member is interposed between the blade mounting surface and the upper surface of the base plate, and the vertical mounting height position with respect to the blade mounting portion of the blade assembly. Is switched to the lower position. As a result, the engagement state between the upper blade driving member and the upper blade is maintained so that the upper blade can be driven by the upper blade driving member, and the lower blade driving member and the lower blade are disengaged from each other. The lower blade is prohibited from being driven by the blade driving member, and the drive mode switching member does not interfere with the upper blade, so that the upper blade is allowed to swing horizontally, and the drive mode switching member interferes with the lower blade. The configuration is such that the horizontal oscillation of the lower blade is restricted. Note that “interfering” in the present invention typically means a state in which the drive mode switching member is in contact (contact) with the lower blade.

  As described above, according to the present invention, the drive mode is switched between the double-blade drive mode and the single-blade drive mode by changing the drive mode switching member between the first position and the second position. be able to. For this reason, when mowing the lawn where there is no fixed object (obstacle), the lawn mowing work can be efficiently performed by driving the upper blade and the lower blade in the double-blade drive mode. On the other hand, when mowing the lawn around fixed objects such as stone walls and garden stones, switch to the single-blade drive mode that prohibits the driving of the lower blade and drive only the upper blade to fix the lower blade to the fixed object. It is possible to perform a trimming operation in such a manner that the grass is trimmed while being slid against the ground. Thereby, the lawn mowing work around the fixed object can be easily performed. As described above, according to the present invention, since the drive mode can be switched according to the work situation, a lawn mower effective for increasing the efficiency of the lawn mowing work is provided.

(Invention of Claim 2)
According to the second aspect of the present invention, the drive mode switching member in the lawn mower according to the first aspect includes a base portion extending in the operation direction of the upper blade and the lower blade, and each end portion in the extending direction of the base portion. And two extending portions extending opposite to each other in a direction intersecting the operation direction of the upper blade and the lower blade. Each extension portion is interposed in a plane contact state with the blade mounting surface and the upper surface of the base plate and interferes with a part of the lower blade when the drive mode switching member is placed at the second position. By doing so, it has an operation restricting portion for restricting the horizontal swinging motion of the lower blade. The “drive mode switching member” of the present invention is typically formed in a U-shaped frame shape. In the present invention, when the drive mode switching member is placed at the second position, each extension is interposed between the blade mounting surface and the upper surface of the base member in a planar contact state. The stability of the mounting state with respect to the blade mounting part of the assembly can be obtained. In addition, the movement restricting part of the extension part interferes with the lower blade, thereby restricting the horizontal swinging motion of the lower blade, thereby securely fixing the lower blade to a predetermined fixing position and moving the lawn relative to the upper blade. Therefore, the pruning operation can be performed smoothly.

(Invention of Claim 3)
According to the third aspect of the present invention, the drive mode switching member in the lawn mower according to the first or second aspect is rotatably mounted on the base plate via the support shaft, thereby integrating with the blade assembly. And is configured to be repositioned between the first position and the second position by rotating around the support shaft. According to the present invention, it is possible to improve the convenience in handling by integrating the drive mode switching member with the blade assembly, and only to turn the drive mode switching member around the support shaft and to reverse it (turn over). Since the position can be easily changed, the workability of the drive mode switching work can be improved.

(Invention of Claim 4)
According to the invention described in claim 4, the support shaft in the lawn mower according to claim 3 can be moved in the vertical direction relative to the base plate, and the drive mode switching member is in the first position and the second position. When the position of the driving mode switching member is shifted between the two, the support shaft moves in the vertical direction, so that the planar contact of the drive mode switching member with the upper surface or the lower surface of the base plate is allowed. According to the present invention, when the drive mode switching member is rotated by using the support shaft as a rotation fulcrum, the position of the rotation fulcrum moves in the vertical direction. It can be in a state per plane with respect to both the upper surface and the lower surface. Thereby, the arrangement space can be reduced in the state placed at the first position, and the interposition state between the blade mounting surface of the main body and the base plate can be optimized in the state placed at the second position.

(Invention of Claim 5)
According to the invention described in claim 5, the upper blade driving member in the lawn mower according to any one of claims 1 to 4, the first cam for driving the upper blade with a predetermined stroke amount; And a second cam that drives the upper blade with a stroke amount larger than the stroke amount of the first cam. When the drive mode switching member is placed at the first position, the first cam engages with the upper blade to drive the upper blade, and when the drive mode switching member is placed at the second position, The second cam is engaged with the upper blade to drive the upper blade. In a double-edged drive lawn mower that drives both the upper and lower blades, when it is configured to switch to the single-blade drive mode by prohibiting the lower blade drive, the upper blade compared to when driving in the double-blade drive mode And the relative stroke amount of the lower blade is reduced. However, according to the present invention, when the drive mode switching member is switched from the first position to the second position to switch from the double-blade drive mode to the single-blade drive mode, the upper blade is larger than the first cam. It is configured to be driven by a second cam that can be driven with a stroke amount. For this reason, it is possible to increase the relative stroke amount between the upper blade and the lower blade in the single blade drive mode, and it is possible to drive with a relative stroke amount preferably equal to that in the double blade drive mode. That is, according to the present invention, even when the double-blade drive mode is switched to the single-blade drive mode, the same pruning performance as in the double-blade drive mode can be maintained.

(Invention of Claim 6)
According to the invention described in claim 6, in the lawn mower according to any one of claims 1 to 5, the cover member that is detachably attached to the lower region of the main body and covers the lower surface side of the blade assembly. And a seal member that closes the gap between the upper surface of the upper blade and the main body, and a seal member that closes the gap between the lower surface of the base plate and the cover member. The seal member is configured to absorb the change in the gap by elastically deforming in the vertical direction when the gap in the vertical direction of the gap changes in accordance with the change in the vertical position of the blade assembly. The “elastic deformation” in the present invention broadly includes an aspect in which the seal member has elasticity, an aspect in which an elastic member that urges the seal member in a resilient manner is provided as a separate member, and the like. As the “seal member”, typically, sponge, elastic rubber or the like is preferably used. According to the present invention, when the vertical position of the blade assembly is changed by switching the drive mode, the change in the gap caused by the change is absorbed by the elastic deformation of the seal member, and the sealing performance can be maintained. Thereby, the penetration | invasion in the main-body part of the cut | disconnected lawn can be prevented.

  According to the present invention, in the lawn mower, there is provided a technique capable of rationally switching between the double-blade drive mode and the single-blade drive mode for the blade drive mode.

(First embodiment of the present invention)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows the overall configuration of the lawn mower with the blade device removed, as a side sectional view, and FIG. 2 shows the configuration of the lawn mower shown in FIG. 1 viewed from the bottom (lower surface) side. 3 to 5 show the overall configuration of the blade device. 6 and 7 show a case where the blade device is driven in the double-blade drive mode, and FIGS. 8 and 9 show a case where the blade device is driven in the single-blade drive mode. 10 to 12 show the configuration of the blade device in a state where the upper blade and the lower blade are removed, and FIG. 13 shows a position change operation mode of the drive mode switching plate in the blade device.

  The overall configuration of the lawn mower 100 according to the present embodiment will be described with reference to FIGS. 1 and 2. The main body 101 of the lawn mower 100 is mainly composed of a housing 103 and a handle (hand grip) 105 arranged to extend on one side of the housing 103 (left side in FIGS. 1 and 2). The main body 101 corresponds to the “main body” in the present invention. Housed in the housing 103 is an electric motor 111 and a rotation drive device 121 that appropriately reduces the rotational output of the electric motor 111 and transmits it to the cam device 131. A cam device 131 is disposed below the rotation drive device 121, and a blade device 151 (see FIGS. 3 to 5) is detachably engaged with the cam device 131. In a state where the blade device 151 is engaged with the cam device 131 (see FIGS. 6 to 9), the blade device is driven based on the rotational drive of the cam device 131 to perform the lawn mowing work. This will be described later. The blades of the blade device 151, that is, the blade portions of the upper blade 152 and the lower blade 153 extend from the lower region of the housing 103 in the direction opposite to the extending direction of the handle 105 (the right side in FIGS. 1 and 2). . For convenience of explanation, the handle 105 side is referred to as the rear, and the extending sides of the upper blade 152 and the lower blade 153 are referred to as the front.

  Next, details of each mechanism will be described. The electric motor 111 is arranged so that the rotation axis is in the vertical direction (vertical direction) with the output shaft 113 on the lower side, and a pinion 115 is formed at the tip (lower end) of the output shaft 113. The handle 105 is provided with a trigger 109 for operating a power switch 107 for energization driving of the electric motor 111.

  The rotary drive device 121 is meshed with and engaged with the pinion 115 of the output shaft 113, and is formed integrally with the intermediate large gear 123 that rotates in the horizontal plane with the first support shaft 122 as the rotation center. The intermediate small gear 124 and the intermediate small gear 124 are engaged with and engaged with each other, and the driven gear 126 that rotates around the second support shaft 125 in the horizontal plane is mainly configured. The first support shaft 122 and the second support shaft 125 are arranged in parallel with the output shaft 113 (the axis is in the vertical direction). The second support shaft 125 has its axial upper end portion secured to the housing 101, and its axial lower portion projects from the lower surface of the driven gear 126 by a predetermined length, and this projecting portion is the cam device 131. It is set as the attachment shaft part 127. That is, the cam device 131 is arranged on the lower surface of the driven gear 126.

  As shown in FIGS. 1 and 2, the cam device 131 includes upper and lower eccentric cams (disk cams) 133 and 135 arranged so as to overlap each other in the thickness direction (up and down direction). The upper eccentric cam 133 is for driving the upper blade, and corresponds to the “upper blade driving member” in the present invention. The lower eccentric cam 135 is for driving the lower blade, and corresponds to the “lower blade driving member” in the present invention. The center of the upper eccentric cam 133 and the center of the lower eccentric cam 135 are decentered (shifted) by a predetermined amount from the rotation center of the mounting shaft portion 127 to the opposite sides. The two eccentric cams 133 and 135 may be formed by processing a single material, or may be formed separately and then joined together by welding or pins or the like.

  A blade mounting portion 141 to which the blade device 151 is mounted is formed at the lower portion of the housing 103. As shown in the bottom view of FIG. 2, the blade mounting portion 141 is formed into a substantially U-shaped frame shape with the front (right side in the drawing) opened, and the lower surface thereof is a blade mounting surface 141a formed substantially horizontally. The A cover mounting portion 143 that protrudes further downward than the blade mounting surface 141a of the blade mounting portion 141 is formed on the outer side of both side surface portions of the blade mounting portion 141. An under cover 145 that covers the base side of the blade device 151 from below is detachably mounted on the cover mounting portion 143, and the blade device 151 is mounted on the blade mounting portion 141 of the housing 103 by the under cover 145. . This will be described later.

  Next, the configuration of the blade device 151 used for lawn mowing will be described with reference to FIGS. The blade device 151 includes an upper blade 152 and a lower blade 153 that are arranged to overlap each other in the vertical direction, a base plate 154 that is a substantially rectangular flat plate on which the upper blade 152 and the lower blade 153 are placed, and an upper blade 152. And a connection pin 155 for connecting the lower blade 153 to the base plate 154 and a drive mode switching plate 157 for switching the drive mode of the upper blade 152 and the lower blade 153 between the double blade drive mode and the single blade drive mode. The The base plate 154 corresponds to a “base plate” in the present invention. The drive mode switching plate 157 has a double-blade drive mode in which both the upper blade 152 and the lower blade 153 are driven with respect to the drive modes of the upper blade 152 and the lower blade 153 driven by the upper and lower eccentric cams 133 and 135. And the single blade drive mode in which only the upper blade 152 is driven and the lower blade 153 is prohibited from driving, and corresponds to the “drive mode switching member” in the present invention. The upper blade 152 and the lower blade 153 are formed in a substantially T shape in plan view, and on the base side corresponding to the T-shaped leg, near the boundary with the blade side corresponding to the T-shaped head, the base plate 154 And a single connecting pin 155, and is relatively rotatable in a horizontal plane with the connecting pin 155 as a rotation center. That is, the upper blade 152 and the lower blade 153 and the base plate 154 on which the upper blade 152 and the lower blade 153 are placed are joined (integrated) via the connecting pin 155, and this joined product is called a blade assembly. The blade assembly corresponds to the “blade assembly” in the present invention. The connection pin 155 corresponds to the “connection shaft” in the present invention.

  Long base holes 152b and 153b that are long in the front-rear direction are formed in the bases of the upper blade 152 and the lower blade 153, respectively (see FIGS. 3 and 4), and the oblong hole 152b of the upper blade 152 is located on the upper side of the cam device 131. The eccentric cam 133 can be engaged (fitted), and the oval hole 153 b of the lower blade 153 can be engaged with the lower eccentric cam 135. The upper blade 152 and the lower blade 153 have comb blade-shaped cutting blades 152a and 153a, respectively. The base plate 154 has a through-hole 154a through which the attachment shaft portion 127 of the second support shaft 125 passes when the blade device 151 is mounted on the blade mounting portion 141.

  As shown in FIGS. 10 to 12, the drive mode switching plate 157 is formed in a substantially U-shaped frame shape in plan view with the front opened. The drive mode switching plate 157 is rotatably attached to the base plate 154 via a support shaft 158 on the rear end side (base side), and rotates around the support shaft 158 as shown in FIG. The position can be changed between a position overlapping the lower surface of 154 and a position overlapping the upper surface. The position overlapping the lower surface corresponds to the “first position” in the present invention, and the position overlapping the upper surface corresponds to the “second position” in the present invention. The support shaft 158 is attached to a long hole 154c of an ear-shaped protrusion 154b formed on both side surfaces of the rear end of the base plate 154 so as to be movable in the vertical direction. The amount of movement of the support shaft 158 in the vertical direction is set to be at least a value obtained by adding the diameter of the support shaft 158 to the thickness (vertical direction dimension) of the base plate 154. For this reason, the drive mode switching plate 157 is moved up and down along with the support shaft 158 while rotating around the support shaft 158 as shown by solid line arrows or broken line arrows in FIG. When the position of the base plate 154 is changed to the side position, it is possible to contact the lower surface or the upper surface of the base plate 154 in a horizontal state. As a result, the tool mounting surface 141a of the tool mounting portion 141 and further the upper surface of the under cover 145 are provided. Surface contact in a horizontal state is possible.

  By switching the arrangement position of the drive mode switching plate 157 with respect to the base plate 154, it is possible to change the mounting height position of the cutter assembly in the vertical direction with respect to the cutter mounting portion 141 of the housing 103. That is, when the drive mode switching plate 157 is placed on the lower surface side of the base plate 154, as shown in FIG. 6, the upper surface of the base plate 154 directly contacts the blade mounting surface 141a of the blade mounting portion 141 in a contact state. However, when the drive mode switching plate 157 is placed on the upper surface side of the base plate 154, the upper surface of the base plate 154 faces the blade mounting surface 141a of the blade mounting portion 141 via the drive mode switching plate 157 as shown in FIG. It is set as the structure contact | abutted in a surface contact state. As a result, the mounting height position of the blade assembly in the vertical direction is changed upward or downward relative to the blade mounting portion 141 by the thickness of the drive mode switching plate 157.

  That is, when the drive mode switching plate 157 is moved to the lower surface side of the base plate 154, the mounting height position of the blade assembly with respect to the blade mounting portion 141 is changed upward. At this time, the upper blade 152 and the lower blade 153 are in the upper position, the upper eccentric cam 133 is engaged with the oblong hole 152b of the upper blade 152, and the lower eccentric cam 135 is engaged with the oblong hole 153b of the lower blade 153. Is configured to be engaged (see FIG. 6). This state is a double-blade drive mode in which both the upper blade 152 and the lower blade 153 are driven, and corresponds to the “double-blade drive mode” in the present invention. When the drive mode switching plate 157 is moved to the upper surface side of the base plate 154, the mounting height position of the blade assembly with respect to the blade mounting portion 141 is changed downward. At this time, the upper blade 152 and the lower blade 153 are in the lower position, and the upper eccentric cam 133 is engaged with the oval hole 152b of the upper blade 152, but the lower oval hole 153b of the lower blade 153 has a lower side. The eccentric cam 135 is not engaged (disengaged) (see FIG. 8). This state is a single-blade drive mode in which only the upper blade 152 is driven and the drive of the lower blade 153 is prohibited (stopped), and corresponds to the “single-blade drive mode” in the present invention.

  The thickness (vertical dimension) of the upper eccentric cam 133 is set to be thicker than that of the lower eccentric cam 135, and a predetermined gap is formed in the vertical direction between the base of the upper blade 152 and the base of the lower blade 153. Has been. With this configuration, the upper blade 152 can be engaged with the upper eccentric cam 133 regardless of whether the mounting height position of the blade device 151 is changed to the upper side or the lower side. When the mounting height position of the blade device 151 is changed upward, the lower blade 153 is engaged with the lower eccentric cam 135, and when the mounting height position of the blade device 151 is changed downward, The engagement with the side eccentric cam 135 can be released. The lower blade 153 has a guide pin 159 that protrudes toward the upper blade 152 at the base side end. The upper end of the guide pin 159 is in contact with the lower surface of the base side end of the upper blade 152 in a state where relative sliding is allowed. Thereby, it is set as the structure by which the contact state between the cutting blades 152a and 153a of the upper blade 152 and the lower blade 153 is appropriately maintained.

  As described above, the drive mode switching plate 157 is formed in a substantially U-shaped frame shape in plan view with the front opened. That is, the base 157a extending in the horizontal swing operation direction of the upper blade 152 and the lower blade 153 and the horizontal swing operation direction of the upper blade 152 and the lower blade 153 from each end in the extending direction of the base 157a. It is set as the structure which has the two extension parts 157b extended mutually facing to the direction. The extension portion 157b is a double-blade drive operation mode that is placed when the drive mode switching plate 157 is repositioned (reverse operation) between the lower surface side position and the upper surface side position of the base plate 154 and at the lower surface side position of the base plate 154. Then, the upper blade 152 and the lower blade 153 are configured not to interfere with each other. On the other hand, in the single-blade drive mode placed at the upper surface side position of the base plate 154, the extension portion 157b is engaged with the base portion of the lower blade 153 by the narrow width portion 157c formed near the base portion 157a of the extension portion 157b. Thus, the horizontal swing operation of the lower blade 153 is restricted. The narrow width portion 157c corresponds to the “operation restricting portion” in the present invention.

  The blade device 151 is detachably mounted on the housing 103 via the under cover 145 in a state where the base plate 154 is in contact with the blade mounting surface 141a of the blade mounting portion 141 directly or via the drive mode switching plate 157. . When the under cover 145 is mounted on the cover mounting portion 143 of the housing 103, its peripheral edge abuts against the lower surface of the drive mode switching plate 157 or the lower surface of the base plate 154 in a surface contact state from below, thereby the base plate 154. The upper surface or the upper surface of the drive mode switching plate 157 is fixed to the blade mounting surface 141a of the blade mounting portion 141 in a pressing manner. The under cover 145 is configured to be attached or detached through a plurality of hook-shaped claws by sliding the cover attaching portion 143 in the horizontal direction in the horizontal direction. Because of this technology, detailed description is omitted.

  As shown in FIG. 6 or FIG. 8, when the blade assembly is mounted on the blade mounting portion 141, the blade assembly passes through an opening formed between the lower surface of the housing 103 and the upper surface of the under cover 145. It is extended to. In the present embodiment, the gap C between the upper surface of the upper blade 152 and the lower surface of the housing 103 and the gap C between the lower surface of the lower blade 153 and the upper surface of the under cover 145 depend on switching between the double-blade drive mode and the single-blade drive mode. It changes with the change of the height position of the blade assembly. Therefore, in the present embodiment, dust seals 161 and 163 are provided on the housing 103 and the under cover 145 to seal (seal) the gap C, and the dust seals 161 and 166 are elastically deformed in the vertical direction. It is set as the structure which can absorb the deformation | transformation of the clearance gap C. FIG. As a means for elastically deforming the dust seals 161 and 163, the dust seals 161 and 163 are formed of a material having elasticity such as sponge, or the dust seals 161 and 163 are elastically formed via an elastic member such as a spring. A configuration that urges in a shape can be appropriately employed.

Lawn mower 100 according to the present embodiment is configured as described above. The operation and usage method will be described below.
When the lawnmower 100 is used in the double-edged drive mode, the drive mode switching plate 157 of the blade device 151 is switched to the lower surface position of the base plate 154. In this state, when the blade device 151 is mounted on the blade mounting portion 141 of the housing 103, the upper surface of the base plate 154 directly contacts the blade mounting surface 141a of the blade mounting portion 141. This state is shown in FIG. 6 and FIG. By mounting as described above, the mounting height position of the blade assembly with respect to the blade mounting portion 141 of the housing 103 becomes the upper position. When mounted in this manner, the upper eccentric cam 133 is engaged with the oval hole 152 b of the upper blade 152, and the lower eccentric cam 135 is engaged with the oval hole 153 b of the lower blade 153. At this time, the drive mode switching plate 157 placed on the lower surface side of the base plate 154 does not interfere with either the upper blade 152 or the lower blade 153.

  In this state, the power switch 107 is turned on (turned on) by pulling the trigger 109, and when the electric motor 111 is energized, the driven gear 126 is moved from the pinion 115 through the intermediate large gear 123 and the intermediate small gear 124. As a result, the upper and lower eccentric cams 133 and 135 of the cam device 131 are rotated in the horizontal plane. Accordingly, the upper blade 152 and the lower blade 153 engaged with the upper and lower eccentric cams 133 and 135 are horizontally oscillated reciprocally in arcs in opposite directions (in opposite phases) with the connecting pin 155 as the rotation center. A motion is performed, and the grass as the object to be cut is sandwiched between the cutting blades 152a and 153a of the upper blade 152 and the lower blade 153 and cut. That is, lawn mowing work is performed in the double-edged drive mode in which the upper blade 152 and the lower blade 153 are driven. At this time, the base side of the upper blade 152 and the lower blade 153 is swung with a movement amount twice as large as the eccentric amounts of the upper and lower eccentric cams 133, 135, and the cutting blades 152a, 153a side is connected to the connecting pin. 155 and the center of the mounting shaft 127 and the moving amount determined by the ratio of the distance from the connecting pin 155 to the distance from the cutting blades 152a and 153a.

  On the other hand, when it is desired to use the lawn mower 100 in the single-blade drive mode, the blade device 151 is temporarily detached from the blade mounting portion 141 of the housing 103. Then, the drive mode switching plate 157 is moved to the upper surface side of the base plate 154, and in that state, the drive mode switching plate 157 is mounted on the blade mounting unit 141 again. At this time, the drive mode switching plate 157 is brought into contact with the blade mounting surface 141a of the blade mounting portion 141. This state is shown in FIGS. That is, the drive mode switching plate 157 is interposed between the base plate 154 and the blade mounting surface 141a of the blade mounting portion 141. Thereby, the mounting height position of the blade assembly with respect to the blade mounting portion 141 of the housing 103 becomes the lower position. When mounted in this manner, the upper eccentric cam 133 is engaged with the oval hole 152b of the upper blade 152, but the lower eccentric cam 135 is not engaged with the oval hole 153b of the lower blade 153. . At this time, the drive mode switching plate 157 does not interfere with the upper blade 152 but interferes with the lower blade 152. That is, the outer surface of the base of the lower blade 153 is engaged with the inner surface of the frame portion of the drive mode switching plate 157 placed on the upper surface side of the base plate 154, thereby moving the lower blade 153 around the connecting pin 155, Oscillating motion is restricted.

  In this state, when the trigger 109 is pulled and the electric motor 111 is energized in accordance with the turning-on operation of the power switch 107, the driven gear 126 is moved from the pinion 115 through the intermediate large gear 123 and the intermediate small gear 124. As a result, the upper and lower eccentric cams 133 and 135 of the cam device 131 are rotated in the horizontal plane. The upper blade 152 that engages with the upper eccentric cam 133 is driven, but the lower blade that has been disengaged from the lower eccentric cam 135 is held in a stopped state. That is, only the upper blade 152 is driven in the single blade drive mode in which the horizontal swing reciprocating motion around the connecting pin 155 is performed.

  As described above, the lawnmower 100 according to the present embodiment drives the upper blade 152 and the double blade driving mode for driving the upper blade 152 and the lower blade 153 for the driving mode of the blade device 151 by the cam device 131. It is possible to switch between the single-blade drive mode for prohibiting the lower blade drive. In the double-blade drive mode, the upper blade 152 and the lower blade 153 both move relative to each other in opposite phases, so that the amount of movement stroke can be increased. For this reason, when mowing a lawn in a wide area without a fixed object (obstacle), the upper blade 152 and the lower blade 153 are driven in the double-blade drive mode to efficiently cut the lawn with a large stroke amount. It can be performed. On the other hand, for example, when mowing the lawn around a fixed object such as a stone wall or garden stone, the lower blade 153 is switched to the single-blade drive mode that prohibits the drive, and only the upper blade 152 is driven, The pruning operation in a mode of cutting the lawn while sliding the blade 153 against the fixed portion is possible. Thereby, the lawn mowing work around the fixed object can be easily performed. That is, the lawn mower 100 according to the present embodiment can be selectively used as a double-blade drive lawn mower or a single-blade drive lawn mower according to work conditions, and can efficiently perform lawn mowing work.

  Further, the drive mode switching plate 157 in the present embodiment includes a base portion 157a and two extension portions extending from the base portion 157a so as to face each other in a direction intersecting the horizontal swinging operation direction of the upper blade 152 and the lower blade 153. 157b. In the single-blade drive mode in which the drive mode switching plate 157 is placed on the upper surface of the base plate 154, each extension 157b is interposed in surface contact with the blade mounting surface 141a and the upper surface of the base plate 154, and the drive mode is switched. In the double-blade drive mode in which the plate 157 is placed on the lower surface of the base plate 154, the plate 157 is interposed between the upper surface of the base plate 154 and the upper surface of the under cover 145 in a surface contact state. For this reason, it becomes possible to mount the blade assembly to the blade mounting portion 141 in a stable state in any drive mode. In the single-blade drive mode, the narrow width portion 157c of the extension portion 157b interferes with the base portion of the lower blade 153, thereby restricting the horizontal swing operation of the lower blade 153. As a result, the lower blade 153 is fixed at a predetermined position and the relative movement operation with respect to the upper blade 152 is maintained, so that the lawn mowing operation by the single blade driving can be performed without any trouble.

  Further, according to the present embodiment, the drive mode switching plate 157 is rotatably attached to the base plate 154 via the support shaft 158, and is integrated with the blade assembly. For this reason, the drive mode switching plate 157 is not separated from the blade assembly during the drive mode switching operation, and is easy to handle. Further, since the drive mode switching plate 157 is rotated around the support shaft 158 so that the position is changed between the lower surface position and the upper surface position of the base plate 154, the drive mode switching plate 157 is rotated around the support shaft 158. It can be easily repositioned simply by moving it and flipping it. Further, since the support shaft 158 can be moved in the vertical direction along the elongated hole 154c of the protrusion 154b of the base plate 154, the drive mode switching plate 157 is rotated with the support shaft 158 as a rotation fulcrum, thereby repositioning. In this case, the drive mode switching plate 157 can be set to an appropriate posture per plane with respect to both the upper surface and the lower surface of the base plate 154 by moving the rotation fulcrum in the vertical direction.

(Second embodiment of the present invention)
Next, a second embodiment of the present invention will be described with reference to FIGS. In the embodiment described above, the stroke amount is constant for driving the upper blade 152 in both the double-blade drive mode and the single-blade drive mode. For this reason, in the single blade drive mode in which the driving of the lower blade 153 is prohibited, there is a possibility that the stroke amount between the blades is insufficient compared to the double blade drive mode in which the lower blade 153 is also driven. Therefore, in the present embodiment, the upper eccentric cam provided for driving the upper blade of the cam device 171 is increased by the first eccentric cam 173 for the double blade drive mode and a stroke amount larger than that of the first eccentric cam 173. The second eccentric cam 175 for driving the blade 152 at the time of the single-blade mode driving is configured to compensate for an insufficient stroke amount between the blades at the time of the single-blade mode driving. Except for this configuration, the configuration is the same as that of the first embodiment described above. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified. The first eccentric cam 173 corresponds to the “first cam portion” in the present invention, and the second eccentric cam 175 corresponds to the “second cam portion” in the present invention.

  The cam device 171 according to the present embodiment has a total of three eccentricities including a first eccentric cam 173 and a second eccentric cam 175 for driving the upper blade, and a third eccentric cam 177 for driving the lower blade in order from the top. The cam is arranged. The three eccentric cams 173, 175, and 177 may be integrally formed by processing a single material, or after being formed separately, they are joined together by welding or pins or the like. Also good. The second eccentric cam 175 that drives the upper blade 152 in the single-blade drive mode is set to have an eccentric amount larger than the eccentric amount of the first eccentric cam 173 that drives the upper blade 152 in the double-blade drive mode. That is, the upper blade 152 is driven with a larger stroke amount, for example, a double stroke amount, in the single blade drive mode driven by the second eccentric cam 175 than in the double blade drive mode driven by the first eccentric cam 173. It is configured as follows.

  The blade device 151 driven by the cam device 171 configured as described above has a blade assembly configured by joining the upper blade 152, the lower blade 153, and the base plate 154 via the connecting pin 155. The same configuration as that of the first embodiment described above is such that the drive mode switching plate 157 is rotatably mounted on the base plate 154 via the support shaft 158.

  14 to 16 show a case where the blade device 151 is driven in the double-blade drive mode. In this double-blade drive mode, the blade device 151 is in a state where the drive mode switching plate 157 is placed at the lower surface side position of the base plate 154 and the upper surface of the base plate 154 is in direct contact with the blade mounting surface 141a of the blade mounting portion 141. It is installed. For this reason, the mounting height position of the blade assembly of the blade device 151 is set to the upper position. In this state, the upper first eccentric cam 173 is engaged with the oval hole 152 b of the upper blade 152, and the lower third eccentric cam 177 is engaged with the oval hole 153 b of the lower blade 153. Therefore, the upper blade 152 and the lower blade 153 are each driven with a predetermined stroke amount as the electric motor 111 is energized. As a result, the cutting blade 152a of the upper blade 152 and the cutting blade 153a of the lower blade 153 face each other with a sufficient opening degree (open) and a cutting preparation position (position shown in FIG. 15) overlaps (closes) each other. The lawn can be efficiently cut by performing a horizontal swing operation with an appropriate stroke amount between the completion position (the position shown in FIG. 16).

  On the other hand, FIGS. 17 to 19 show a case where the blade device 151 is driven in the single-blade drive mode. In this one-blade drive mode, the blade device 151 has the drive mode switching plate 157 placed at the upper surface side position of the base plate 154, and the base plate 154 contacts the blade mounting surface 141a of the blade mounting portion 141 via the drive mode switching plate 157. It is mounted in the state that was done. For this reason, the mounting height position of the blade assembly of the blade device 151 is set to the lower position. In this state, the second eccentric cam 175 at the intermediate position is engaged with the oval hole 152 b of the upper blade 152, and the lower blade 153 is not engaged with the third eccentric cam 177. Accordingly, only the upper blade 152 is driven as the electric motor 111 is energized, and the lower blade 153 is not driven. At this time, the upper blade 152 is driven with a stroke amount approximately twice that in the double-blade drive mode. For this reason, as in the double-blade drive mode, the cutting blade 152a of the upper blade 152 and the cutting blade 153a of the lower blade 153 are opposed to each other with a sufficient cutting opening position (position shown in FIG. 18). A horizontal swing operation can be performed with an appropriate stroke amount between overlapping cutting completion positions (positions shown in FIG. 19). That is, the lawn can be efficiently cut even in the single-blade drive mode as in the double-blade drive mode.

  Thus, according to the present embodiment, it is possible to drive the upper blade 152 with an appropriate stroke amount without excess or deficiency in both the double-blade drive mode and the single-blade drive mode, and to efficiently perform the lawn mowing work. . The lawn mower 100 according to the present embodiment has not only the above-described operational effects, but also the same operational effects as the first embodiment, but this is meant to avoid redundant explanation. Description is omitted.

  In the above-described embodiment, the drive mode switching plate 157 is rotatably mounted on the base plate 154 via the support shaft 158 so that the position can be changed between the upper surface side position and the lower surface side position of the base plate 154. Although it is assembled, it is not limited to this configuration. For example, the drive mode switching plate 157 is detachably mounted on the upper surface and the lower surface of the base plate 154, or is detachably mounted on the blade mounting surface 141a of the blade mounting portion 141 and the inner surface (upper surface) of the under cover 145. The configuration may be changed so that the base plate 154 is replaced between the upper surface side position and the lower surface side position.

In view of the gist of the present invention, the following modes can be configured.
(Aspect 1)
“A lawnmower according to claim 4,
The vertical movement amount of the support shaft is set to be at least a value obtained by adding the diameter of the support shaft to the thickness of the base plate, whereby the drive mode switching member is moved to the first position and the first position. A lawnmower characterized in that the driving mode switching member overlaps the upper or lower surface of the base plate in a planar contact state when the position is changed between the second position and the second position. "

It is a sectional side view which shows the whole structure of the lawn mower in the state where the blade apparatus which concerns on the 1st Embodiment of this invention was removed. It is a bottom view of the lawn mower in FIG. It is a top view which shows a blade apparatus. It is a bottom view which shows a blade apparatus. It is sectional drawing which shows a cutter apparatus. It is a sectional side view of the lawn mower in the case of driving a blade apparatus in a double blade drive mode. It is a bottom view of the lawn mower in FIG. However, the under cover is omitted. It is a sectional side view of a lawn mower in the case of driving a blade device in a single blade drive mode. It is a bottom view of the lawn mower in FIG. However, the under cover is omitted. It is a top view of the cutter apparatus in the state where the upper blade and the lower blade were removed. It is a bottom view of the cutter apparatus of the state from which the upper blade and the lower blade were similarly removed. It is sectional drawing of the cutter apparatus in the state where the upper blade and the lower blade were removed. It is a figure which shows the position change operation | movement aspect of the drive mode switching plate in a blade apparatus. It is a sectional side view which shows the whole structure of the lawn mower which concerns on 2nd Embodiment, and shows the time of the double blade drive mode. Similarly, it is a bottom view of the lawn mower in the double blade drive mode, and shows a state where the upper blade and the lower blade are placed in the open position (cutting preparation position). However, the under cover is omitted. Similarly, it is a bottom view of the lawn mower in the double blade drive mode, and shows a state where the upper blade and the lower blade are placed at the closed position (cutting completion position). However, the under cover is omitted. It is a sectional side view which shows the whole structure of the lawn mower which concerns on 2nd Embodiment, and shows the time of single blade drive mode. Similarly, it is a bottom view of the lawn mower in the single-blade drive mode, and shows a state where the upper blade and the lower blade are placed in the open position (cutting preparation position). However, the under cover is omitted. Similarly, it is a bottom view of the lawn mower in the single blade drive mode, and shows a state in which the upper blade and the lower blade are placed at the closed position (cutting completion position). However, the under cover is omitted.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Lawn mower 101 Main part 103 Housing 105 Handle 107 Power switch 109 Trigger 111 Electric motor 113 Output shaft 115 Pinion 121 Rotation drive device 122 First support shaft 123 Intermediate large gear 124 Intermediate small gear 125 Second support shaft 126 Driven gear 127 Mounting shaft 131 Cam device 133 Upper eccentric cam (upper blade drive member)
135 Lower eccentric cam (lower blade drive member)
141 Cutter mounting portion 141a Cutter mounting surface 143 Cover mounting portion 145 Under cover (cover member)
151 Cutter device 152 Upper blade 152a Cutting blade 152b Oval hole 153 Lower blade 153a Cutting blade 153b Oval hole 154 Base plate (base plate)
154a Through-hole 154b Protrusion 154c Long hole 155 Connection pin (connection shaft)
157 Drive mode switching plate (drive mode switching member)
157a Base portion 157b Extension portion 157c Narrow width portion (operation restricting portion)
158 Support shaft 159 Guide pin 171 Cam device 173 First eccentric cam (first cam)
175 Second eccentric cam (second cam)
177 Third eccentric cam

Claims (6)

The main body,
A blade mounting portion having a generally horizontal blade mounting surface formed in a lower region of the main body portion;
A base plate, and an upper blade and a lower blade that are arranged above and below to overlap each other on the upper surface of the base plate, and a connecting shaft that connects the upper blade and the lower blade to the base plate so as to be horizontally swingable. And a blade assembly that is detachable from the blade mounting portion,
An upper blade driving member that drives the upper blade by rotating in a state of being engaged with the upper blade;
A lower blade driving member that drives the lower blade opposite to the upper blade by rotating in a state of being engaged with the lower blade;
With respect to the driving modes of the upper blade and the lower blade by the upper blade driving member and the lower blade driving member, by maintaining the engagement between the upper blade driving member and the upper blade, A double-blade drive mode that enables driving of the lower blade by the lower blade drive member by maintaining the engagement between the lower blade drive member and the lower blade, and the upper blade drive member The upper blade can be driven by the upper blade driving member by maintaining the engagement between the lower blade and the upper blade, and the lower blade can be driven by releasing the engagement between the lower blade driving member and the lower blade. A lawnmower capable of switching between a single blade drive mode for prohibiting driving of the lower blade by a drive member,
A drive mode switching member that switches the drive mode between the double-edged drive mode and the single-edged drive mode;
The drive mode switching member is placed on the lower surface of the base plate to place the drive mode in the double-blade drive mode, and placed on the upper surface of the base plate to drive the drive mode to the single-blade drive. The position can be changed between the second position to switch to the mode,
When the drive mode switching member is placed at the first position, the mounting height position in the vertical direction with respect to the blade mounting portion of the blade assembly is set to the upper position, thereby the upper blade driving member and the upper blade And the engagement state of the lower blade driving member and the lower blade are maintained, respectively, and the upper blade and the lower blade can be driven by the upper blade driving member and the lower blade driving member. The drive mode switching member is configured to allow horizontal swing operation of the upper blade and the lower blade by allowing neither the upper blade nor the lower blade to interfere,
When the drive mode switching member is placed at the second position, the drive mode switching member is interposed between the blade mounting surface and the upper surface of the base plate, and the vertical direction of the blade assembly with respect to the blade mounting portion. The mounting height position of the upper blade is switched to the lower position, whereby the engagement state between the upper blade driving member and the upper blade is maintained, and the upper blade can be driven by the upper blade driving member. The lower blade driving member is disengaged from the lower blade, the lower blade driving member is prohibited from driving the lower blade, and the drive mode switching member does not interfere with the upper blade, A lawnmower characterized in that a horizontal swing operation of the blade is allowed and the horizontal swing operation of the lower blade is restricted by the drive mode switching member interfering with the lower blade. The lawn mower according to claim 1,
The drive mode switching member is opposed to each other in a direction that intersects the operation direction of the upper blade and the lower blade from each end of the base portion extending in the operation direction of the upper blade and the lower blade. Have two extensions that extend,
Each of the extensions is interposed in a plane contact state with respect to the blade mounting surface and the upper surface of the base plate when the drive mode switching member is placed at the second position. A lawnmower having an operation restricting part that restricts horizontal swinging action of the lower blade by interfering with the part. A lawnmower according to claim 1 or 2,
The drive mode switching member is rotatably mounted on the base plate via a support shaft, thereby being integrated with the blade assembly, and rotating around the support shaft to move the first position and the A lawnmower that is repositioned between the second position and the second position. A lawnmower according to claim 3,
The support shaft is movable up and down relative to the base plate, and when the drive mode switching member is repositioned between the first position and the second position, the support shaft is moved up and down. The lawn mower has a configuration in which the planar contact of the drive mode switching member with respect to the upper surface or the lower surface of the base plate is allowed by moving to the base plate. A lawnmower according to any one of claims 1 to 4,
The upper blade driving member includes a first cam that drives the upper blade with a predetermined stroke amount, and a second cam that drives the upper blade with a stroke amount larger than the stroke amount of the first cam. And when the drive mode switching member is placed at the first position, the first cam engages with the upper blade to enable the upper blade to be driven, and the drive mode switching member is the second. A lawnmower characterized in that the second cam engages with the upper blade to enable the upper blade to be driven when placed in the position. A lawnmower according to any one of claims 1 to 5,
A cover member that is detachably attached to a lower region of the main body, and covers a lower surface side of the blade assembly;
A seal member that closes the gap between the upper blade upper surface and the main body, and a seal member that closes the gap between the lower surface of the base plate and the cover member,
The seal member is configured to absorb the change in the gap by elastically deforming in the vertical direction when the gap in the vertical direction of the gap changes in accordance with the switching of the vertical position of the cutter assembly. Lawn mower.

Images