Working machine

Abstract

To provide an implement capable of suppressing movement of an object to be cut, to a power conversion mechanism.SOLUTION: An implement comprises: a motor; a power conversion mechanism for converting the power from the motor; a first blade connected to the power conversion mechanism; a second blade which is overlapped to the first blade in a vertical direction, and faces a first facing surface of the first blade; a seal member which is engaged to a first non-facing surface which is at an opposite side of the first facing surface of the first blade, and has a first seal surface facing the first non-facing surface of the first blade in the vertical direction; and a cover member which faces a second seal surface at an opposite side of the first seal surface of the seal member. The first blade reciprocates along the first direction with respect to the second blade. The seal member is arranged on a front side of the power conversion mechanism, in a cross direction being orthogonal to the vertical direction, and suppresses an object to be cut which is cut by the first and second blades from moving toward the power conversion mechanism between the first blade and the cover member.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present invention relates to a working machine.

Background Art

[0002] Patent Document 1 discloses a blade unit. The blade unit includes a first blade, a second blade that overlaps the first blade in the vertical direction and faces a first facing surface of the first blade, a scraper locked to the first facing surface of the first blade, and a guide member that overlaps the second blade on the side opposite to the first blade with respect to the second blade in the vertical direction. The guide member has a through hole penetrating in the vertical direction. When the first blade reciprocates along a first direction with respect to the second blade, the scraper also reciprocates along the first direction with respect to the second blade. When the scraper reciprocates along the first direction with respect to the second blade, foreign matter (such as soil) between the first blade and the guide member is pushed out in the direction along the first direction by the scraper and discharged from between the first blade and the guide member through the through hole.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When the blade unit as described above is used in a working machine (e.g., a lawn trimmer) equipped with a power conversion mechanism, the blade unit is connected, for example, to the front side of the power conversion mechanism. When an object to be cut such as grass or turf is cut by the first blade and the second blade, most of the object to be cut is pushed out in the direction along the first direction by the scraper as the scraper reciprocates. However, a part of the object to be cut may move beyond the scraper and reach the power conversion mechanism. This specification discloses a technique capable of suppressing the movement of the object to be cut to the power conversion mechanism.

Means for Solving the Problems

[0005] The working machine disclosed in this specification includes a prime mover, a power conversion mechanism that converts the power of the prime mover, a first blade connected to the power conversion mechanism, a second blade that overlaps the first blade in the vertical direction and faces the first opposing surface of the first blade, a seal member that is locked to the first non-opposing surface on the opposite side of the first opposing surface of the first blade and has a first sealing surface that faces the first non-opposing surface of the first blade in the vertical direction, and a cover member that faces the second sealing surface on the opposite side of the first sealing surface of the seal member. The first blade has a first cutting edge. The second blade has a second cutting edge. Due to the power of the prime mover, the first blade reciprocates along the first direction with respect to the second blade. When the working machine moves forward along the front-rear direction perpendicular to the vertical direction while the first blade is reciprocating with respect to the second blade, the first cutting edge of the first blade and the second cutting edge of the second blade cut the object to be cut. The seal member is disposed on the front side of the power conversion mechanism in the front-rear direction, and suppresses the object to be cut cut by the first cutting edge of the first blade and the second cutting edge of the second blade from moving toward the power conversion mechanism between the first blade and the cover member.

[0006] According to the above configuration, the object to be cut is suppressed from moving toward the power conversion mechanism by the seal member. Further, since the seal member is locked to the first blade, the seal member reciprocates along the first direction with respect to the second blade together with the first blade. Thereby, the seal member pushes out the object to be cut in the direction along the first direction. By adopting such a configuration, it is possible to suppress the object to be cut from moving toward the power conversion mechanism.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Embodiments for Carrying Out the Invention

[0008] Hereinafter, representative and non-limiting specific examples of the present invention will be described in detail with reference to the drawings. This detailed description is merely intended to show those skilled in the art the details for implementing preferred examples of the present invention, and is not intended to limit the scope of the present invention. In addition, the additional features and inventions disclosed below can be used separately or together with other features and inventions in order to provide a more improved working machine, its manufacturing method, and usage method.

[0009] Also, the combinations of features and steps disclosed in the following detailed description are not essential for implementing the present invention in the broadest sense, and are described only for explaining representative specific examples of the present invention in particular. Furthermore, the various features of the above and below representative specific examples, as well as the various features described in the independent and dependent claims, do not have to be combined as described in the specific examples here or in the order listed when providing additional and useful embodiments of the present invention.

[0010] All features described in this specification and / or the claims are intended to be disclosed separately and independently of each other as limitations to the initial disclosure and the claimed specific matters, apart from the configurations of the features described in the examples and / or claims. Furthermore, all descriptions regarding numerical ranges and groups or populations are made with the intention of disclosing intermediate configurations as limitations to the initial disclosure and the claimed specific matters.

[0011] In one or more embodiments, the seal member may reciprocate along the first direction together with the first blade. The cover member may be provided with a discharge port. The inlet of the discharge port may be arranged at a position facing the seal member with respect to the first direction.

[0012] According to the above configuration, the object to be cut is pushed toward the inlet of the discharge port by the reciprocating motion of the seal member. Thereby, the object to be cut can be easily discharged from the working machine.

[0013] In one or more embodiments, the outlet of the discharge port may be disposed at a position facing the inlet of the discharge port with respect to the first direction.

[0014] According to the above configuration, when the object to be cut enters the discharge port from the inlet of the discharge port, it moves along the first direction to the outlet of the discharge port. Thereby, the object to be cut can be more easily discharged from the working machine.

[0015] In one or more embodiments, the cover member may be disposed on the rear side of the discharge port with respect to the front-rear direction, and may be provided with a grease guard for suppressing the movement of grease.

[0016] Grease is applied to the power conversion mechanism to reduce friction associated with its operation. When the power conversion mechanism operates, the applied grease may scatter from the power conversion mechanism. According to the above configuration, the grease scattered from the power conversion mechanism is less likely to move to the discharge port due to the grease guard. Thereby, it is possible to suppress the grease from being discharged from the discharge port to the outside of the working machine.

[0017] In one or more embodiments, the cover member may extend toward the first non-facing surface of the first blade and may be provided with a protruding wall disposed on the front side of the seal member. When the working machine is viewed in the front-rear direction, the protruding wall may at least partially overlap with the seal member.

[0018] According to the above configuration, with respect to the front-rear direction, the protruding wall closes at least a part of the gap between the second seal surface of the seal member and the cover member. Thereby, it is possible to further suppress the object to be cut from moving beyond the seal member toward the power conversion mechanism.

[0019] (Example) As shown in FIG. 1, the working machine 2 of the present embodiment is a gardening electric working machine, for example, a ground trimmer, and is used for mowing grass, turf, etc. growing on the ground. The working machine 2 includes a linearly extending operation lever 4, a rear end unit 6 attached to one longitudinal end of the operation lever 4, a front end unit 8 attached to the other longitudinal end of the operation lever 4, a pair of wheels 10 attached near the other longitudinal end of the operation lever 4, a loop handle 12 attached near the center in the longitudinal direction of the operation lever 4, and a battery pack BP. The working machine 2 operates using the electric power supplied from the battery pack BP. The user can move the working machine 2 on the ground while cutting grass, turf, etc. growing on the ground by pushing the working machine 2 forward to rotate the pair of wheels 10 while gripping the rear end unit 6 with one hand and the loop handle 12 with the other hand. Hereinafter, the direction in which the working machine 2 moves when the pair of wheels 10 rotate is referred to as the front-rear direction, the direction orthogonal to the ground is referred to as the vertical direction, and the direction orthogonal to both the front-rear direction and the vertical direction is referred to as the left-right direction. Also, the direction in which the working machine 2 is moved to cut grass, turf, etc. growing on the ground using the working machine 2 (the direction in which the working machine 2 is pushed out in the present embodiment) is referred to as the front direction, and the direction opposite to the front direction is referred to as the rear direction.

[0020] As shown in FIG. 2, the rear end unit 6 includes a rear end housing 16. The rear end housing 16 includes a support portion 18, a grip portion 20, and a battery attachment portion 22.

[0021] The operation lever 4 is inserted into the support portion 18. A main power switch 24 is disposed on the upper surface of the support portion 18. The main power switch 24 switches between the on state and the off state of the working machine 2.

[0022] The grip portion 20 is disposed on the rear side of the support portion 18. A trigger 26 is rotatably attached to the lower front side of the grip portion 20. The trigger 26 is pushed in by the finger of the user's hand gripping the grip portion 20. When the working machine 2 is in the on state, when the trigger 26 is pushed in, an electric motor 32 (see FIG. 3) described later operates.

[0023] Also, a shark fin 28 is rotatably attached to the upper front side of the gripping portion 20. The shark fin 28 is pushed in by the palm of the user's hand that grips the gripping portion 20. In a state where the shark fin 28 is pushed in, the user can push in the trigger 26. On the other hand, in a state where the shark fin 28 is not pushed in, the user cannot push in the trigger 26.

[0024] The battery attachment portion 22 is disposed on the rear side of the gripping portion 20. A battery pack BP is detachably attached to the rear end of the battery attachment portion 22. The battery pack BP can be attached to the battery attachment portion 22 by sliding the battery pack BP along the rear end of the battery attachment portion 22 from the upper side to the lower side with respect to the battery attachment portion 22. Also, the battery pack BP can be removed from the battery attachment portion 22 by sliding the battery pack BP along the rear end of the battery attachment portion 22 from the lower side to the upper side with respect to the battery attachment portion 22 in a state where the battery pack BP is attached to the battery attachment portion 22. Therefore, the battery pack BP can be removed from the battery attachment portion 22 and charged.

[0025] Inside the battery attachment portion 22, as shown in FIG. 3, an electric motor 32 and a speed reduction mechanism 34 are accommodated. The electric motor 32 is an example of a prime mover. The electric motor 32 is, for example, a brushless motor. In a modified example, the electric motor 32 may be a brushed motor. The electric motor 32 operates by electric power supplied from the battery pack BP (see FIG. 2).

[0026] The speed reduction mechanism 34 includes a first speed reduction gear 34a and a second speed reduction gear 34b. The first speed reduction gear 34a and the second speed reduction gear 34b are spur gears. The first speed reduction gear 34a is connected to the motor shaft 32a of the electric motor 32. The second speed reduction gear 34b meshes with the first speed reduction gear 34a. The number of teeth of the second speed reduction gear 34b is larger than the number of teeth of the first speed reduction gear 34a. When the first speed reduction gear 34a rotates with the rotation of the motor shaft 32a of the electric motor 32, the second speed reduction gear 34b rotates at a rotational speed lower than the rotational speed of the first speed reduction gear 34a.

[0027] A transmission shaft 36 is connected to the second speed reduction gear 34b. The transmission shaft 36 extends from the rear end unit 6 (see FIG. 1), passes through the inside of the operation lever 4 (see FIG. 1), and reaches the front end unit 8 (see FIG. 1). The transmission shaft 36 rotates with the rotation of the second speed reduction gear 34b.

[0028] As shown in FIG. 4, the front end unit 8 is attached to the operation lever 4 on the front side of the pair of wheels 10. The front end unit 8 includes a front end housing 40, a speed reduction mechanism 42 (see FIG. 5), a power conversion mechanism 44 (see FIG. 5), and a blade unit 46.

[0029] As shown in FIG. 5, the front end housing 40 includes a gear housing 50 and a cover member 52. The gear housing 50 is connected to the front end of the operation lever 4 using a screw (not shown). The cover member 52 closes the lower end opening of the gear housing 50. Thereby, a gear accommodation chamber 56 is formed between the gear housing 50 and the cover member 52.

[0030] The reduction mechanism 42 is disposed in the gear housing chamber 56. The reduction mechanism 42 includes a third reduction gear 42a and a fourth reduction gear 42b. The third reduction gear 42a and the fourth reduction gear 42b are bevel gears. The third reduction gear 42a is connected to the front end of the transmission shaft 36. The fourth reduction gear 42b meshes with the third reduction gear 42a. The number of teeth of the fourth reduction gear 42b is larger than the number of teeth of the third reduction gear 42a. When the third reduction gear 42a rotates as the transmission shaft 36 rotates, the fourth reduction gear 42b rotates at a rotational speed lower than the rotational speed of the third reduction gear 42a. Also, the fourth reduction gear 42b rotates around a rotation axis along the vertical direction.

[0031] The power conversion mechanism 44 is a cam-crank type conversion mechanism. The power conversion mechanism 44 includes a crankshaft 60, an upper disk 62, and a lower disk 64. The crankshaft 60 is rotatably supported by the gear housing 50 and the cover member 52 via bearings 66 and 68. The crankshaft 60 is connected to the fourth reduction gear 42b. Also, the crankshaft 60 passes through the cover member 52, and the lower end of the crankshaft 60 is disposed outside the gear housing chamber 56.

[0032] The upper disk 62 and the lower disk 64 are connected to the lower end of the crankshaft 60. The upper disk 62 and the lower disk 64 have a disk shape. The upper disk 62 and the lower disk 64 rotate due to the rotation of the crankshaft 60. The rotation center of the upper disk 62 is offset from the center of the disk shape of the upper disk 62, and the rotation center of the lower disk 64 is offset from the center of the disk shape of the lower disk 64. When the upper disk 62 rotates from the rear side toward the front side, the lower disk 64 rotates from the front side toward the rear side, and when the upper disk 62 rotates from the front side toward the rear side, the lower disk 64 rotates from the rear side toward the front side. Note that grease for reducing the friction between the upper disk 62 and the lower disk 64 is applied to the upper disk 62 and the lower disk 64.

[0033] Referring to FIG. 6, the blade unit 46 will be described. The blade unit 46 of this embodiment can mow grass, turf, etc. growing on the ground. The blade unit 46 includes a first blade 70, a second blade 72, an intermediate plate 74, a first guide member 76, a second guide member 78, and a seal member 80.

[0034] The first blade 70 includes a first blade body 82, a plurality of first blade tips 84, and a first crank plate 86. The first blade body 82 extends in the left-right direction. The first blade body 82 has a plurality of first elongated holes 88 having a longitudinal direction in the left-right direction. The first elongated holes 88 penetrate the first blade body 82 in the thickness direction (up-down direction). The plurality of first blade tips 84 project forward from the front surface 82a of the first blade body 82 extending along the left-right direction. The plurality of first blade tips 84 are arranged side by side in the left-right direction. The first crank plate 86 is disposed near the center in the left-right direction of the first blade body 82 and on the rear side of the first blade body 82. The first crank plate 86 has a plurality (two in this embodiment) of locking holes 90 and a first crank opening 92 disposed rearward of the plurality of locking holes 90. The two locking holes 90 penetrate the first crank plate 86 in the up-down direction. The two locking holes 90 are arranged side by side in the left-right direction. The first crank opening 92 penetrates the first crank plate 86 in the up-down direction.

[0035] As shown in FIG. 6, the second blade 72 overlaps the lower side of the first blade 70 in the vertical direction. The second blade 72 has a shape that coincides with the shape of the first blade 70. The second blade 72 includes a second blade body 96, a plurality of second blade tips 98, and a second crank plate 100. The second blade body 96 extends in the left - right direction. In a state where the second blade body 96 overlaps the first blade body 82, the front surface 96a of the second blade body 96 is aligned vertically with the front surface 82a of the first blade body 82, the rear surface 96b of the second blade body 96 is aligned vertically with the rear surface 82b of the first blade body 82, and the upper surface 96c of the second blade body 96 faces the lower surface 82c of the first blade body 82. The second blade body 96 has a plurality of second elongated holes 102 having a longitudinal direction in the left - right direction. The second elongated holes 102 penetrate the second blade body 96 in the thickness direction (vertical direction). The plurality of second blade tips 98 project forward from the front surface 96a of the second blade body 96 extending along the left - right direction. The plurality of second blade tips 98 are arranged side by side in the left - right direction. The second crank plate 100 is disposed near the center of the second blade body 96 in the left - right direction and on the rear side of the second blade body 96. The second crank plate 100 has a second crank opening 104 penetrating the second crank plate 100 in the vertical direction.

[0036] As shown in FIG. 6, the intermediate plate 74 overlaps the upper side of the first blade 70 in the vertical direction. The intermediate plate 74 is disposed on the side opposite to the second blade 72 with respect to the first blade 70. The intermediate plate 74 extends in the left - right direction. Projection pieces 108 extending forward are formed at both ends of the intermediate plate 74. The intermediate plate 74 closes the plurality of first elongated holes 88 of the first blade body 82 from above in the vertical direction. The intermediate plate 74 has a plurality of intermediate screw holes 74a penetrating the intermediate plate 74 in the thickness direction (vertical direction). The plurality of intermediate screw holes 74a are arranged side by side in the left - right direction.

[0037] The first guide member 76 overlaps the upper side of the intermediate plate 74 in the vertical direction. The first guide member 76 is disposed on the side opposite to the first blade 70 with respect to the intermediate plate 74. The first guide member 76 extends in the left-right direction. The first guide member 76 has a plurality of first screw holes 76a penetrating the first guide member 76 in the thickness direction (vertical direction). The plurality of first screw holes 76a are arranged in the left-right direction.

[0038] The second guide member 78 overlaps the lower side of the second blade 72 in the vertical direction. The second guide member 78 is disposed on the side opposite to the first blade 70 with respect to the second blade 72. The second guide member 78 includes a second guide member main body 112 and a cover member 114. The second guide member main body 112 extends in the left-right direction. The second guide member main body 112 closes a plurality of second long holes 102 of the second blade main body 96 from below in the vertical direction. The second guide member main body 112 has a plurality of second front screw holes 112a penetrating the second guide member main body 112 in the thickness direction (vertical direction). The plurality of second front screw holes 112a are arranged in the left-right direction. The cover member 114 is disposed near the center in the left-right direction of the second guide member main body 112 and on the rear side of the second guide member main body 112. The cover member 114 includes a plurality of second rear screw holes 114a penetrating the cover member 114 in the thickness direction (vertical direction) and a recess 114b recessed downward from the upper surface of the cover member 114.

[0039] The seal member 80 is locked to the upper surface of the first crank plate 86 in the vicinity of the connection location between the first blade body 82 and the first crank plate 86 in the vertical direction. The seal member 80 is disposed closer to the first blade body 82 side than the step region formed on the first crank plate 86. The upper surface of the first crank plate 86 constitutes a part of the upper surface of the first blade 70. Also, the seal member 80 is disposed behind the first blade tip 84 and the second blade tip 98. As shown in FIG. 7, the seal member 80 includes a seal member body 118, a right wall 120, a left wall 122, and a plurality (two in this embodiment) of locking protrusions 124. The seal member body 118 extends in the left - right direction. The lower surface 118a of the seal member body 118 faces the upper surface of the first crank plate 86. The lower surface 118a of the seal member body 118 constitutes the lower surface of the seal member 80. The width of the seal member body 118 in the left - right direction is longer than the width of the first crank plate 86 in the left - right direction. The right wall 120 extends downward from the right end of the seal member body 118. The left wall 122 extends downward from the left end of the seal member body 118. The first crank plate 86 is sandwiched between the right wall 120 and the left wall 122. This suppresses the seal member 80 from moving in the left - right direction with respect to the first blade 70. The two locking protrusions 124 extend downward from the lower surface 118a of the seal member body 118. In the left - right direction, the two locking protrusions 124 are disposed between the right wall 120 and the left wall 122. Each locking protrusion 124 is inserted into each locking hole 90 of the first crank plate 86. This suppresses the seal member 80 from moving in the front - rear direction and the left - right direction with respect to the first blade 70.

[0040] As shown in FIG. 6, the first blade 70, the second blade 72, the intermediate plate 74, the first guide member 76, and the second guide member 78 are fixed by screws 128 and nuts 130. At this time, the screws 128 are inserted into the second front screw hole 112a of the second guide member 78, the first long hole 88 of the first blade 70, the second long hole 102 of the second blade 72, the intermediate screw hole 74a of the intermediate plate 74, and the first screw hole 76a of the first guide member 76. The nut 130 receives the screw 128 above the first guide member 76. Between the leftmost screw 128 and the rightmost screw 128, a washer 132 is sandwiched between the screw head of the screw 128 and the second guide member 78. Also, an annular sleeve 134 is disposed in the first long hole 88 of the first blade 70 and the second long hole 102 of the second blade 72. The screw 128 is inserted into the sleeve 134. The sleeve 134 guides the reciprocating movement in the left-right direction of the first blade 70 and the second blade 72.

[0041] Also, as shown in FIG. 5, in a state where the first blade 70, the second blade 72, the intermediate plate 74, the first guide member 76, and the second guide member 78 are assembled, the second guide member 78 is fixed to the lower side of the cover member 52 by inserting the screw 136 into the second rear screw hole 114a (see FIG. 6). Thereby, a crank chamber 140 is formed between the cover member 52 and the recess 114b of the second guide member 78. In the crank chamber 140, the upper disk 62 of the power conversion mechanism 44, the lower disk 64, the first crank plate 86 of the first blade 70, and the second crank plate 100 of the second blade 72 are disposed.

[0042] With the first blade 70, the second blade 72, the intermediate plate 74, the first guide member 76, and the second guide member 78 assembled, when the second guide member 78 is fixed to the lower side of the cover member 52, the upper disk 62 is disposed in the first crank opening 92 of the first crank plate 86, and the lower disk 64 is disposed in the second crank opening 104 of the second crank plate 100. As the upper disk 62 rotates while contacting the inner surface of the first crank opening 92, the first blade 70 reciprocates in the left - right direction with respect to the front housing 40. Also, as the lower disk 64 rotates while contacting the inner surface of the second crank opening 104, the second blade 72 reciprocates in the left - right direction with respect to the front housing 40. Further, when the second blade 72 moves to the left side, the first blade 70 moves to the right side, and when the second blade 72 moves to the right side, the first blade 70 moves to the left side.

[0043] Next, with reference to FIG. 8, the detailed structure of the cover member 52 that defines the crank chamber 140 will be described. The cover member 52 includes an upper wall 144, a U - shaped wall 146, a right inclined wall 148, a left inclined wall 150, and a front wall 152. The upper wall 144 defines a gear housing chamber 56 (see FIG. 5) between it and the gear housing 50 (see FIG. 5). The upper wall 144 has an upper opening 144a into which the crankshaft 60 (see FIG. 5) is inserted.

[0044] The U - shaped wall 146, the right inclined wall 148, the left inclined wall 150, and the front wall 152 are disposed below the upper wall 144. The U - shaped wall 146 has a substantially U - shaped configuration when the cover member 52 is viewed from below. The U - shaped wall 146 is open toward the front side.

[0045] The right inclined wall 148 extends from the right front end of the U - shaped wall 146 toward the front right side, then bends and extends toward the right side. Near the connection point between the right inclined wall 148 and the right front end of the U - shaped wall 146, a right grease guard 156 is formed. The right grease guard 156 protrudes to the left side more than the inner surface of the right front end of the U - shaped wall 146.

[0046] The left inclined wall 150 extends from the left front end of the U-shaped wall 146 toward the front left, and then bends and extends toward the left. Near the connection point between the left inclined wall 150 and the left front end of the U-shaped wall 146, a left grease guard 158 is formed. The left grease guard 158 protrudes to the right more than the inner surface of the left front end of the U-shaped wall 146.

[0047] The front wall 152 extends in the left-right direction from the front end of the upper wall 144. The front wall 152 includes a right protruding wall 162, a left protruding wall 164, and a central protruding wall 166. The right protruding wall 162 is disposed on the front side of the right inclined wall 148. The right protruding wall 162 is offset to the front side more than the right inclined wall 148. Thereby, a right discharge port 170 is formed between the right protruding wall 162 and the right inclined wall 148. The right discharge port 170 communicates the crank chamber 140 with the external space of the working machine 2. In the left-right direction, the inlet 170a of the right discharge port 170 faces the outlet 170b of the right discharge port 170. As shown in FIG. 9, the width of the right discharge port 170 in the front-rear direction is shorter than the width of the seal member 80 in the front-rear direction.

[0048] As shown in FIG. 8, the left protruding wall 164 is disposed on the front side of the left inclined wall 150. The left protruding wall 164 is offset to the front side more than the left inclined wall 150. Thereby, a left discharge port 172 is formed between the left protruding wall 164 and the left inclined wall 150. The left discharge port 172 communicates the crank chamber 140 with the external space of the working machine 2. In the left-right direction, the inlet 172a of the left discharge port 172 faces the outlet 172b of the left discharge port 172. As shown in FIG. 9, the width of the left discharge port 172 in the front-rear direction is shorter than the width of the seal member 80 in the front-rear direction.

[0049] As shown in FIG. 8, the central protruding wall 166 is disposed between the right protruding wall 162 and the left protruding wall 164. The vertical length of the central protruding wall 166 is shorter than both the vertical length of the right protruding wall 162 and the vertical length of the left protruding wall 164. Thereby, a front end opening 174 is formed below the central protruding wall 166 between the right protruding wall 162 and the left protruding wall 164.

[0050] Next, the positional relationship between the cover member 52 and the blade unit 46 will be described. As shown in FIG. 9, in a state where the blade unit 46 is attached to the cover member 52, the first crank plate 86 of the first blade 70 and the second crank plate 100 (see FIG. 6) of the second blade 72 are inserted into the front end opening 174 of the cover member 52. The seal member 80 is disposed on the rear side of the front end opening 174. Further, the seal member 80 is disposed on the front side of the upper disk 62 and the lower disk 64 (see FIG. 5) in the crank chamber 140 (that is, closer to the front than the power conversion mechanism 44). Also, in the left-right direction, the seal member 80 faces both the inlet 170a of the right discharge port 170 and the inlet 172a of the left discharge port 172. As shown in FIG. 10, the seal member 80 is disposed on the rear side of the central protruding wall 166. When the blade unit 46 is viewed in the front-rear direction, the seal member 80 at least partially overlaps with the central protruding wall 166. The seal member 80 and the central protruding wall 166 form a labyrinth structure. Further, the upper surface 118b of the seal member body 118 faces the upper wall 144 of the cover member 52. Note that the upper surface 118b of the seal member body 118 constitutes the upper surface of the seal member 80. The upper surface 118b of the seal member body 118 is separated from the upper wall 144. The central protruding wall 166 extends toward the upper surface of the first crank plate 86. In the front-rear direction, the central protruding wall 166 is disposed between the seal member 80 and the intermediate plate 74. When the blade unit 46 is viewed in the front-rear direction, the central protruding wall 166 at least partially overlaps with the intermediate plate 74.

[0051] Next, the behavior of cutting an object to be cut, such as grass or turf, by the first blade 70 and the second blade 72 will be described. As described above, when the electric motor 32 operates, the power of the electric motor 32 is transmitted to the first blade 70 and the second blade 72 via the transmission shaft 36 (see FIG. 3) and the power conversion mechanism 44 (see FIG. 5), and the first blade 70 and the second blade 72 reciprocate in the left-right direction with respect to the front housing 40. When the working machine 2 is pushed forward, the object to be cut is sandwiched between the first cutting edge 84 of the first blade 70 and the second cutting edge 98 of the second blade 72 and is cut.

[0052] The cut object to be cut may move rearward between the first blade 70 and the intermediate plate 74 as the first blade 70 reciprocates along the left-right direction. When the object to be cut exceeds the intermediate plate 74, it moves toward the central protruding wall 166 of the cover member 52. The object to be cut cannot move through the gap between the upper surface 118b of the seal member body 118 and the cover member 52 due to the labyrinth structure formed by the seal member 80 and the central protruding wall 166. This suppresses the movement of the object to be cut toward the power conversion mechanism 44.

[0053] Also, since the first blade 70 is reciprocating in the left-right direction, as shown in FIG. 9, the object to be cut whose rearward movement is suppressed by the seal member 80 is pushed rightward by the right wall 120 of the seal member 80. The pushed object to be cut enters the interior of the right discharge port 170 from the inlet 170a of the right discharge port 170. The entered object to be cut moves rightward inside the right discharge port 170 and is then discharged to the outside of the crank chamber 140 from the outlet 170b of the right discharge port 170.

[0054] Furthermore, the object to be cut whose rearward movement is suppressed by the seal member 80 may be pushed leftward by the left wall 122 of the seal member 80. The pushed object to be cut enters the interior of the left discharge port 172 from the inlet 172a of the left discharge port 172. The entered object to be cut moves leftward inside the left discharge port 172 and is then discharged to the outside of the crank chamber 140 from the outlet 172b of the left discharge port 172.

[0055] Also, when the object to be cut is discharged outside the crank chamber 140, the upper disk 62 and the lower disk 64 (see FIG. 5) of the power conversion mechanism 44 are operating. At this time, a part of the grease adhering to the upper disk 62 and the lower disk 64 may scatter from the upper disk 62 and the lower disk 64. The scattered grease moves forward along the U-shaped wall 146 in the crank chamber 140. The grease that has moved to the front end of the U-shaped wall 146 is blocked by the right grease guard 156 and the left grease guard 158 and cannot move forward beyond the right grease guard 156 and the left grease guard 158. As a result, it becomes difficult for the grease to be discharged outside the crank chamber 140 through the right discharge port 170 and the left discharge port 172.

[0056] (Effect) The working machine 2 includes an electric motor 32, a power conversion mechanism 44 that converts the power of the electric motor 32, a first blade 70 connected to the power conversion mechanism 44, a second blade 72 that overlaps the first blade 70 in the vertical direction and faces the lower surface of the first blade 70, a seal member 80 that is locked to the upper surface on the opposite side of the lower surface of the first blade 70 and has a lower surface facing the upper surface of the first blade 70 in the vertical direction, and a cover member 52 that faces the upper surface on the opposite side of the lower surface of the seal member 80. The first blade 70 includes a first blade tip 84. The second blade 72 includes a second blade tip 98. By the power of the electric motor 32, the first blade 70 reciprocates along the left-right direction with respect to the second blade 72. When the working machine 2 moves forward along the front-rear direction perpendicular to the vertical direction in a state where the first blade 70 is reciprocating with respect to the second blade 72, the first blade tip 84 of the first blade 70 and the second blade tip 98 of the second blade 72 cut the object to be cut. The seal member 80 is disposed on the front side of the power conversion mechanism 44 in the front-rear direction and suppresses the object to be cut cut by the first blade tip 84 of the first blade 70 and the second blade tip 98 of the second blade 72 from moving between the first blade 70 and the cover member 52 toward the power conversion mechanism 44.

[0057] According to the above configuration, the object to be cut is suppressed from moving toward the power conversion mechanism 44 by the seal member 80. Further, since the seal member 80 is locked to the first blade 70, the seal member 80 reciprocates in the left - right direction along with the first blade 70 with respect to the second blade 72. Thereby, the seal member 80 pushes out the object to be cut in the direction along the left - right direction. By adopting such a configuration, it is possible to suppress the object to be cut from moving toward the power conversion mechanism 44.

[0058] Also, the seal member 80 reciprocates in the left - right direction along with the first blade 70. The cover member 52 is provided with discharge ports 170 and 172. The inlets 170a and 172a of the discharge ports 170 and 172 are arranged at positions facing the seal member 80 in the left - right direction.

[0059] According to the above configuration, the object to be cut is pushed out toward the inlets 170a and 172a of the discharge ports 170 and 172 by the reciprocating motion of the seal member 80. Thereby, the object to be cut can be easily discharged from the working machine 2.

[0060] Also, the outlets 170b and 172b of the discharge ports 170 and 172 are arranged at positions facing the inlets 170a and 172a of the discharge ports 170 and 172 in the left - right direction.

[0061] According to the above configuration, when the object to be cut enters the discharge ports 170 and 172 from the inlets 170a and 172a of the discharge ports 170 and 172, it moves to the outlets 170b and 172b of the discharge ports 170 and 172 along the left - right direction. Thereby, the object to be cut can be more easily discharged from the working machine 2.

[0062] Also, the cover member 52 is arranged on the rear side of the discharge ports 170 and 172 in the front - rear direction and is provided with grease guards 156 and 158 for suppressing the movement of grease.

[0063] According to the above configuration, grease is applied to the power conversion mechanism 44 in order to reduce friction associated with its operation. When the power conversion mechanism 44 operates, the applied grease may scatter from the power conversion mechanism 44. According to the above configuration, the grease scattered from the power conversion mechanism 44 is made difficult to move to the discharge ports 170 and 172 by the grease guards 156 and 158. Thereby, it is possible to suppress the grease from being discharged outside the working machine 2 from the discharge ports 170 and 172.

[0064] Further, the cover member 52 extends toward the upper surface of the first blade 70 and includes a central protruding wall 166 disposed in front of the seal member 80. When the working machine 2 is viewed in the front-rear direction, the central protruding wall 166 at least partially overlaps with the seal member 80.

[0065] According to the above configuration, in the front-rear direction, the central protruding wall 166 closes at least a part of the gap between the upper surface of the seal member 80 and the cover member 52. Thereby, it is possible to further suppress the object to be cut from moving toward the power conversion mechanism 44 beyond the seal member 80.

[0066] (Corresponding relationship) The lower surface of the first blade 70 is an example of the "first facing surface". The upper surface of the first blade 70 is an example of the "first non-facing surface". The lower surface of the seal member 80 is an example of the "first seal surface". The upper surface of the seal member 80 is an example of the "second seal surface". The left-right direction is an example of the "first direction". The central protruding wall 166 is an example of the "protruding wall".

[0067] (Modification) In one embodiment, the working machine 2 may be a lawn trimmer.

[0068] In one embodiment, the working machine 2 may not include the battery pack BP and may operate using power supplied from an external power source via an external cord.

[0069] In one embodiment, the working machine 2 may not include the pair of wheels 10.

[0070] In one embodiment, the working machine 2 may be provided with an engine instead of the electric motor 32.

[0071] In one embodiment, the blade unit 46 may include a seal member that is locked to the lower surface of the second blade 72. In this case, the seal member is disposed between the second blade 72 and the second guide member 78. According to this configuration, it is possible to suppress the object to be cut from moving from between the second blade 72 and the second guide member 78 toward the power conversion mechanism 44.

[0072] In one embodiment, the width of the right discharge port 170 in the front-rear direction may be longer than the width of the seal member 80 in the front-rear direction. Also, the width of the left discharge port 172 in the front-rear direction may be longer than the width of the seal member 80 in the front-rear direction.

[0073] In one embodiment, the first blade 70 may further include a cutting edge disposed on the rear surface 82b of the first blade body 82. Also, the second blade 72 may further include a cutting edge disposed on the rear surface 96b of the second blade body 96.

[0074] In one embodiment, the first blade 70 and the second blade 72 may reciprocate linearly (in the left-right direction in the embodiment) or may reciprocate in an arc shape. When the first blade 70 and the second blade 72 reciprocate in an arc shape, the first blade 70 and the second blade 72 reciprocate so as to rotate about a rotation axis along the vertical direction. That is, the first direction is a direction along the circumferential direction of the rotation axis.

[0075] In the above embodiment, by pushing out the working machine 2, the object to be cut is cut by the first cutting edge 84 of the first blade 70 and the second cutting edge 98 of the second blade 72. In one embodiment, when the user pulls the working machine 2 in the direction towards the user, the object to be cut may be cut by the first cutting edge 84 of the first blade 70 and the second cutting edge 98 of the second blade 72. In this case, the direction in which the working machine 2 is pulled is the forward direction. Further, from the front side to the rear side (i.e., in the direction away from the user), the first cutting edge 84 (second cutting edge 98), the central protruding wall 166, the seal member 80, and the power conversion mechanism 44 are arranged in sequence. Furthermore, when the user operates using the working machine 2, the first cutting edge 84 and the second cutting edge 98 face the user. According to the above configuration, it is possible to suppress the object to be cut, which has been cut by the first cutting edge 84 and the second cutting edge 98, from moving towards the power conversion mechanism by the central protruding wall 166 and the seal member 80.

Explanation of Reference Numerals

[0076] 2: Working machine 4: Operating lever 6: Rear end unit 8: Front end unit 10: Wheels 32: Electric motor 36: Transmission shaft 40: Front end housing 44: Power conversion mechanism 46: Blade unit 52: Cover member 56: Gear housing 70: First blade 72: Second blade 76: First guide member 78: Second guide member 80: Seal member 82: First blade body 84: First cutting edge 96: Second blade body 98: Second cutting edge 112: Second guide member body 114: Cover member 118: Seal member body 140: Crank chamber 148: Right inclined wall 150: Left inclined wall 156: Right grease guard 158: Left grease guard 166: Central protruding wall 170: Right discharge port 172: Left discharge port BP: Battery pack

Claims

1. A working machine, including a prime mover, a power conversion mechanism that converts the power of the prime mover, a first blade connected to the power conversion mechanism, a second blade that overlaps the first blade in the vertical direction and faces a first facing surface of the first blade, a seal member that is locked to a first non-facing surface of the first blade opposite to the first facing surface of the first blade and has a first sealing surface that faces the first non-facing surface of the first blade in the vertical direction, and a cover member that faces a second sealing surface of the seal member opposite to the first sealing surface, The first blade includes a first cutting edge, The second blade includes a second cutting edge, By the power of the prime mover, the first blade reciprocates along a first direction with respect to the second blade, When the working machine moves forward along a front-rear direction orthogonal to the vertical direction while the first blade is reciprocating with respect to the second blade, the first cutting edge of the first blade and the second cutting edge of the second blade cut an object to be cut, The seal member is disposed on the front side of the power conversion mechanism in the front-rear direction, and suppresses the object to be cut cut by the first cutting edge of the first blade and the second cutting edge of the second blade from moving between the first blade and the cover member toward the power conversion mechanism. The seal member reciprocates along the first direction together with the first blade. The cover member includes a discharge port, An inlet of the discharge port is disposed at a position facing the seal member in the first direction. A working machine.

2. An outlet of the discharge port is disposed at a position facing the inlet of the discharge port in the first direction. The working machine according to claim 1.

3. The cover member is disposed rearward of the discharge port in the front-rear direction and includes a grease guard that suppresses the movement of grease. The working machine according to claim 1 or 2.

4. The cover member includes a protruding wall that extends toward the first non-facing surface of the first blade and is disposed forward of the seal member. When the working machine is viewed in the front-rear direction, the protruding wall at least partially overlaps the seal member. The working machine according to any one of claims 1 to 3.

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