Working machine

Abstract

To provide a technology which can inhibit foreign objects from entering a housing.SOLUTION: A working machine includes: a working part; a prime mover which causes the working part to operate; a housing which holds the working part and houses the prime mover; a trigger lever which spans the interior and the exterior of the housing through a through hole formed at the housing and is operated by a user; a sensor which is disposed in the housing and detects motion of a portion existing in the housing of the trigger lever; and a control unit which controls the prime mover according to a detection result of the sensor. The trigger lever is supported through a rotary shaft so as to be rotatable relative to the housing. The trigger lever includes a shield part having a rotating body shape centered on a rotation axis of the trigger lever. A peripheral edge part of the through hole includes an opposing edge part facing an outer peripheral surface of the shield part.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The technology disclosed in this specification relates to a work machine. [Background technology]

[0002] Patent Document 1 discloses a working machine including a working unit, a prime mover for operating the working unit, a housing for holding the working unit and accommodating the prime mover, a trigger lever operated by a user, a sensor disposed inside the housing, and a control unit for controlling the prime mover according to the detection result of the sensor. The trigger lever is entirely disposed outside the housing. The sensor is configured to detect the movement of the trigger lever that is present outside the housing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Publication No. 2016 / 0219793 Summary of the Invention [Problem to be solved by the invention]

[0004] In the work machine of Patent Document 1, the sensor and the trigger lever are blocked by the housing, so the accuracy of the detection of the trigger lever by the sensor may be poor. In order to improve this, a through hole is provided in the housing, the trigger lever is placed between the inside and outside of the housing through the through hole, and the movement of the part of the trigger lever that is inside the housing is detected by the sensor. However, in this configuration, there is a risk that foreign matter such as dust may enter the inside of the housing through a gap provided between the periphery of the through hole and the trigger lever. This specification provides a technology that can suppress the intrusion of foreign matter into the inside of the housing. [Means for solving the problem]

[0005] The working machine disclosed in this specification includes a working unit, a prime mover for operating the working unit, a housing for holding the working unit and accommodating the prime mover, a trigger lever that spans between the inside and outside of the housing via a through hole formed in the housing and is operated by a user, a sensor that is disposed inside the housing and detects the movement of a portion of the trigger lever that is present inside the housing, and a control unit that controls the prime mover in accordance with the detection result of the sensor. The trigger lever is rotatably supported on the housing via a rotating shaft. The trigger lever includes a shielding portion having a shape of a rotating body centered on the rotation axis of the trigger lever. The peripheral portion of the through hole includes an opposing edge portion that faces an outer circumferential surface of the shielding portion.

[0006] The trigger lever can take various positions relative to the housing. Depending on the position of the trigger lever, it is expected that the gap provided between the peripheral portion of the through hole and the trigger lever will expand. If the gap provided between the peripheral portion of the through hole and the trigger lever expands, foreign matter will easily enter the inside of the housing. According to the above configuration, since the shielding portion has a rotating body shape centered on the rotation axis of the trigger lever, even if the trigger lever rotates, the distance between the outer circumferential surface of the shielding portion and the opposing edge portion is maintained constant. Therefore, among the gaps provided between the peripheral portion of the through hole and the trigger lever, at least the gap provided between the outer circumferential surface of the shielding portion and the opposing edge portion can be kept narrow regardless of the position of the trigger lever. Therefore, it is possible to suppress the intrusion of foreign matter into the inside of the housing. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a perspective view of pruning scissors 2 according to an embodiment, viewed from above on the front right. [Diagram 2] FIG. 2 is an exploded view showing the configuration of the vicinity of a working part 12 of the pruning scissors 2 according to the embodiment. [Diagram 3] 1 is a view of the internal structure of pruning scissors 2 according to an embodiment of the present invention when the movable blades 8 of the pruning scissors 2 are in the open position, as viewed from the right. [Figure 4] 1 is a view of a trigger through-hole 100 provided in a housing 4 of pruning shears 2 according to an embodiment, viewed from the lower rear right. [Diagram 5] 2 is a diagram showing a configuration in the vicinity of a trigger lever 10 of pruning scissors 2 according to an embodiment. FIG. [Figure 6] 1 is a view of the trigger lever 10 in the zero position of the pruning scissors 2 according to the embodiment, as viewed from the right. [Figure 7] 1 is a right view of the trigger lever 10 of the pruning shears 2 according to the embodiment at the maximum raised position. FIG. [Figure 8] 2 is a diagram showing a configuration in the vicinity of a sensor board 90 of pruning scissors 2 according to an embodiment. FIG. [Figure 9] 1 is a view of the internal structure of pruning scissors 2 according to an embodiment of the present invention, viewed from the right, when movable blades 8 of the pruning scissors 2 are in a closed position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Representative and non-limiting examples of the present invention are described in detail below with reference to the drawings. This detailed description is intended simply to provide those skilled in the art with details for implementing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Additionally, the additional features and inventions disclosed can be used separately or together with other features and inventions to provide further improved working machines.

[0009] In addition, the combinations of features and steps disclosed in the following detailed description are not essential for implementing the present invention in the broadest sense, but are specifically described only to illustrate representative embodiments of the present invention. Furthermore, the various features of the following representative embodiments and the various features described in the claims do not have to be combined in the exact manner of the embodiments described herein or in the order listed in order to provide additional and useful embodiments of the present invention.

[0010] All features described in the specification and / or claims are intended to be disclosed individually and independently of one another as limitations to the specific features described in the original disclosure and claims, apart from the configuration of features described in the examples and / or claims. Furthermore, all numerical ranges and group or aggregate descriptions are intended to disclose intermediate configurations thereof as limitations to the specific features described in the original disclosure and claims.

[0011] In one or more embodiments, the shielding portion may be disposed so as to substantially entirely cover the through hole. The trigger lever may further include an operating portion extending from the shielding portion, disposed outside the housing, and operated by the user, and a detection portion extending from the shielding portion, disposed inside the housing, and detected by the sensor. The operating portion may have a rod shape.

[0012] A typical trigger lever has an operating part operated by a user that has a thickness in the circumferential direction of the rotation axis. This operating part is arranged so as to span the inside and outside of the housing through a through hole, and is configured to be pushed into the inside of the housing by the user. However, in this configuration, the shielding part does not block almost the entire through hole. In this case, there is only one opposing edge part that faces the outer circumferential surface of the shielding part, so there is only one gap that is kept narrow regardless of the position of the trigger lever. According to the above configuration, the shielding part is arranged so as to block almost the entire through hole. In this case, there are two opposing edges that face the outer circumferential surface of the shielding part so as to sandwich the outer circumferential surface of the shielding part. Therefore, there are two gaps that are kept narrow regardless of the position of the trigger lever. Therefore, it is possible to suppress the intrusion of foreign matter into the inside of the housing over a relatively wide range.

[0013] In one or more embodiments, the through hole may open in a direction substantially opposite to a direction from a point where the through hole is provided toward the working unit.

[0014] When the working unit is operated, it is expected that foreign matter such as dust will scatter in the vicinity of the working unit. Therefore, if the through hole is open toward the working unit, the foreign matter scattered as the working unit operates may enter the inside of the housing. According to the above configuration, the through hole opens in a direction substantially opposite to the direction toward the working unit from the location where the working unit is provided. Therefore, it is possible to prevent the foreign matter scattered as the working unit operates from entering the inside of the housing.

[0015] In one or more embodiments, the sensor may include at least one of a magnetic sensor and a microswitch.

[0016] According to the above configuration, since a general-purpose sensor is used, the configuration of the work machine can be simplified.

[0017] In one or more embodiments, the rotational movement of the trigger lever relative to the housing may be limited to within a predetermined range of motion, and the angle of rotation of the trigger lever when rotating from one end of the range to the other end may be less than 45 degrees.

[0018] If the movable range of the trigger lever relative to the housing is excessively large, it becomes bothersome for the user to operate the trigger lever. With the above configuration, the movable range of the trigger lever relative to the housing is limited to an appropriate size, thereby reducing the bothersomeness felt by the user when operating the trigger lever.

[0019] In one or more embodiments, the shielding portion may be disposed so as to substantially entirely block the through hole. The trigger lever may further include an operation portion extending from the shielding portion, disposed outside the housing, and operated by the user, and a detection portion extending from the shielding portion, disposed inside the housing, and detected by the sensor. The operation portion may have a rod shape. The rotational movement of the trigger lever relative to the housing may be limited within a predetermined movable range. When a portion of the outer circumferential portion of the shielding portion that is exposed to the outside of the housing through the through hole in the process of the trigger lever rotating from one end to the other end of the movable range is defined as an exposed portion, an angular range in which the exposed portion exists in the circumferential direction of the rotation axis may be 90 degrees or more.

[0020] If the space inside the housing is occupied by the shielding portion, the housing will become large. With the above configuration, most of the shielding portion can be exposed to the outside of the housing. Therefore, the space inside the housing that is occupied by the shielding portion can be reduced. As a result, the housing can be made smaller.

[0021] In one or more embodiments, the working portion may be configured to perform a cutting operation to cut an object to be cut, or a cutting operation to cut an object to be cut.

[0022] In the above configuration, dust may be generated during cutting (or milling) by the working unit. Therefore, it is considered that a relatively large amount of foreign matter may enter the housing in the environment in which the working machine is used. Therefore, the above configuration significantly suppresses the entry of foreign matter into the housing.

[0023] In one or more embodiments, the work machine may be a handheld work machine that the user can carry with one hand.

[0024] According to the above configuration, it becomes easier for the user to handle the work machine.

[0025] (Example) As shown in Fig. 1, the working machine of this embodiment is pruning scissors 2. The pruning scissors 2 are mainly used for cutting tree branches and the like. The pruning scissors 2 are an electric working machine that operates by power supplied from an external power source. The pruning scissors 2 can be held and carried by a user in one hand.

[0026] The pruning scissors 2 include a housing 4, a fixed blade 6, a movable blade 8, and a trigger lever 10. Although details will be described later, the pruning scissors 2 perform cutting work by rotating the movable blade 8 relative to the fixed blade 6 in response to a pulling operation of the trigger lever 10. The fixed blade 6 and the movable blade 8 are formed of metal (e.g., iron). In this specification, the fixed blade 6 and the movable blade 8 may be collectively referred to as the "working unit 12."

[0027] The housing 4 includes a left housing 14, a right housing 16, a gear housing 18, and a cover housing 20. The left housing 14, the right housing 16, the gear housing 18, and the cover housing 20 are all formed of plastic. The left housing 14 and the right housing 16 are fixed to each other by screws. The gear housing 18 is supported by the left housing 14 and the right housing 16. The cover housing 20 is fixed to the left housing 14 and the right housing 16 by screws. The housing 4 is provided with a grip portion 22 to be gripped by a user and a protection portion 24 to protect the trigger lever 10.

[0028] In this specification, the longitudinal direction of the grip portion 22 is defined as the front-rear direction. In the front-rear direction, the direction from the grip portion 22 toward the working portion 12 is defined as the front direction, and the direction from the working portion 12 toward the grip portion 22 is defined as the rear direction. The direction perpendicular to the front-rear direction and along the rotation axis of the movable blade 8 is defined as the left-right direction. In the left-right direction, the direction from the movable blade 8 toward the fixed blade 6 is defined as the left direction, and the direction from the fixed blade 6 toward the movable blade 8 is defined as the right direction. The direction perpendicular to the front-rear direction and the left-right direction is defined as the up-down direction. In the up-down direction, the direction from the protective portion 24 toward the trigger lever 10 is defined as the up direction, and the direction from the trigger lever 10 toward the protective portion 24 is defined as the down direction.

[0029] An operation unit 26 is provided at the upper rear portion of the housing 4. The operation unit 26 includes a power switch 28 for switching the main power supply on / off, an adjustment switch 30 (described in detail below), and the like. In addition, a display unit 32 is provided at the upper front portion of the housing 4. The display unit 32 includes an LED (not shown) for displaying the on / off state of the main power supply, and the like.

[0030] As shown in Fig. 2, the pruning scissors 2 further include a co-tightening bolt 34, a blade holder 36, a connecting pin 38, a co-tightening nut 40, a lock screw 42, a lock plate 44, and an O-ring 46. In this embodiment, the central axis of the co-tightening bolt 34 is called "axis A1". The central axis of the connecting pin 38 is called "axis A2". The central axis of the lock screw 42 is called "axis A3". The axes A1, A2, and A3 each extend along the left-right direction.

[0031] The co-fastening bolt 34 is formed with, from the left, a male thread 48, a fitting portion 50, and a cylindrical portion 52. The co-fastening bolt 34 is a so-called stepped bolt. The fitting portion 50 has a shape corresponding to a fitting hole 54 provided in the gear housing 18.

[0032] The blade holder 36 has a first through hole 56 and a second through hole 58 provided in front of the first through hole 56. The first through hole 56 rotatably receives the cylindrical portion 52 of the co-fastening bolt 34. Therefore, the blade holder 36 is rotatable around the axis A1 with respect to the gear housing 18. The right portion of the connecting pin 38 is inserted into the second through hole 58. The connecting pin 38 is fixed to the blade holder 36 while being inserted into the second through hole 58. In addition, a first cylindrical portion 60 (see FIG. 8) protruding leftward from the periphery of the first through hole 56 and a bevel gear 62 are formed on the left surface of the blade holder 36.

[0033] The movable blade 8 has a third through hole 64 into which the first cylindrical portion 60 of the blade holder 36 is inserted, and a fourth through hole 66 into which the left portion of the connecting pin 38 is inserted. The movable blade 8 is constrained by the blade holder 36 with respect to the axis A1 and the axis A2. This allows the movable blade 8 to rotate integrally with the blade holder 36 around the axis A1 relative to the gear housing 18.

[0034] The fixed blade 6 has a fifth through hole 68 and a sixth through hole 70 provided behind the fifth through hole 68. A second cylindrical portion 72 protruding rightward from the right surface of the gear housing 18 is inserted into the fifth through hole 68. A female screw 74 is provided on the inner surface of the sixth through hole 70.

[0035] The co-tightening nut 40 has a female thread 76 corresponding to the male thread 48 of the co-tightening bolt 34. The co-tightening bolt 34 and the co-tightening nut 40 fasten the blade holder 36, the movable blade 8, and the fixed blade 6 to the gear housing 18 by screwing the male thread 48 into the female thread 76. Specifically, the co-tightening bolt 34 and the co-tightening nut 40 restrain the blade holder 36, the movable blade 8, and the fixed blade 6 in the left-right direction. The user can adjust the force (hereinafter simply referred to as "tightening force") that tightens the gear housing 18, the fixed blade 6, the movable blade 8, and the blade holder 36 in the left-right direction by tightening (or loosening) the co-tightening nut 40 to the co-tightening bolt 34. If the tightening force is too weak, the movable blade 8 will rattle against the fixed blade 6, and the sharpness of the pruning scissors 2 may decrease. On the other hand, if the tightening force is too strong, a large resistance force is generated in the movable blade 8 when the movable blade 8 is rotated relative to the fixed blade 6. This may increase the load on the electric motor 86 (see FIG. 3) that rotates the movable blade 8.

[0036] The lock screw 42 has a male thread 78 that corresponds to the female thread 74 provided on the fixed blade 6. In addition, the gear housing 18 is provided with a seventh through hole 80 behind the fitting hole 54, through which the female thread 74 of the lock screw 42 can pass. When the male thread 78 is screwed into the female thread 74 of the fixed blade 6 with the female thread 74 of the lock screw 42 passing through the seventh through hole 80, the fixed blade 6 is fastened to the gear housing 18. As a result, the fixed blade 6 is fixed to the gear housing 18.

[0037] The lock plate 44 and the O-ring 46 are attached to the lock screw 42. The lock plate 44 and the O-ring 46 function as a so-called washer. A plurality of teeth 82 are formed on the outer periphery of the lock plate 44. Although not shown, a plurality of teeth corresponding to the plurality of teeth 82 of the lock plate 44 are formed on the outer periphery of the co-locking nut 40. When the fixed blade 6 is fixed to the gear housing 18, the lock screw 42 is fastened in a state in which the plurality of teeth 82 of the lock plate 44 are engaged with the plurality of teeth of the co-locking nut 40. When the fastening by the lock screw 42 is completed, the rotation of the lock plate 44 relative to the gear housing 18 is prohibited, and therefore the rotation of the co-locking nut 40 engaged with the lock plate 44 is also prohibited. This prevents the co-locking nut 40 from loosening, etc., and thus prevents the fastening force from unintentionally changing.

[0038] If it is desired to adjust the fastening force by fastening (or loosening) the co-tightening nut 40, it is necessary to first loosen and remove the lock screw 42. With the lock screw 42 removed, moving the lock plate 44 to the left will release the engagement between the co-tightening nut 40 and the lock plate 44. This allows the co-tightening nut 40 to rotate, making it possible to adjust the fastening force.

[0039] As shown in FIG. 3, the pruning scissors 2 further includes a control device 84, an electric motor 86, a power transmission mechanism 88, a sensor board 90, and a connector 92. The control device 84, the electric motor 86, the power transmission mechanism 88, and the sensor board 90 are accommodated inside the housing 4. A portion of the connector 92 is accommodated inside the housing 4, and the remaining portion is exposed to the outside of the housing 4. The connector 92 is an interface for electrically connecting an external power source to the pruning scissors 2. For example, a power cable (not shown) extending from the external power source is connected to the connector 92. The pruning scissors 2 can receive power from the external power source via the connector 92.

[0040] The control device 84 includes a memory, a CPU, and the like. The control device 84 is electrically connected to each of the operation unit 26, the display unit 32, the electric motor 86, the sensor board 90, and the connector 92. The control device 84 controls the operation of the pruning shears 2 in accordance with a predetermined program stored in the memory. For example, the control device 84 switches between a state in which power supply from an external power source to the electric motor 86 is permitted and a state in which power supply is blocked, depending on the on / off state of the main power source. The control device 84 also controls the display unit 32 to display the on / off state of the main power source, etc.

[0041] The electric motor 86 is, for example, a brushless motor. When power is supplied to the electric motor 86, the electric motor 86 rotates a motor shaft (not shown) extending along the front-rear direction.

[0042] The power transmission mechanism 88 includes a planetary gear mechanism (not shown) connected to the motor shaft (not shown), and a gear shaft 94 connected to the planetary gear mechanism. The planetary gear mechanism reduces the rotation of the motor shaft and transmits it to the gear shaft 94. The gear shaft 94 is supported by a bearing (not shown) provided inside the gear housing 18 so as to be rotatable about an axis along the front-rear direction. A bevel gear 96 corresponding to the bevel gear 62 (see FIG. 2) formed on the left side of the blade holder 36 is formed on the front part of the gear shaft 94. A part of the gear shaft 94 (bevel gear 96) meshes with the bevel gear 62 of the blade holder 36 through an opening 98 formed on the right side of the gear housing 18. The bevel gears 62, 96 convert the rotation of the gear shaft 94 into the rotation of the blade holder 36 and the movable blade 8. When the electric motor 86 is driven, power is transmitted to the movable blade 8 via the motor shaft, the planetary gear mechanism, the gear shaft 94, and the bevel gears 62 and 96. This causes the movable blade 8 to rotate.

[0043] As shown in FIG. 4, the housing 4 is provided with a trigger through-hole 100 for passing the trigger lever 10 (see FIG. 1). The trigger through-hole 100 is formed in a bottom wall of a recess 102 provided on the outer surface of the housing 4. The recess 102 and the trigger through-hole 100 are formed at a connection point between the left housing 14 and the right housing 16. The trigger through-hole 100 opens in a direction substantially opposite to the direction toward the working unit 12 from the point where the trigger through-hole 100 is provided (a diagonally upward forward direction in the example of FIG. 4). The left housing 14 is provided with a left shaft 104 that protrudes to the right at the point where the trigger through-hole 100 is provided. The right housing 16 is provided with a right shaft 106 that protrudes to the left at the point where the trigger through-hole 100 is provided. The left shaft 104 and the right shaft 106 face each other in the left-right direction.

[0044] As shown in FIG. 5, the trigger lever 10 includes a shielding portion 108 arranged to cover substantially the entire trigger through-hole 100 (see FIG. 4). The shielding portion 108 includes a left recess 110 (see FIG. 8) into which the left shaft 104 (see FIG. 4) is inserted, and a right recess 112 into which the right shaft 106 (see FIG. 4) is inserted. The trigger lever 10 is rotatably supported by the housing 4 via the left shaft 104 and the right shaft 106. In this embodiment, the axis of rotation of the trigger lever 10 is called the "axis A4". In addition, the circumferential direction of the axis A4 that is clockwise as viewed from the right is called the "clockwise direction", and the counterclockwise direction as viewed from the right is called the "counterclockwise direction". The shielding portion 108 has a rotating body shape (for example, a cylindrical shape) centered on the axis A4. The outer diameter of the shielding portion 108 is in the range of 5 mm to 11 mm, and is about 8 mm in this embodiment.

[0045] The trigger lever 10 further includes an operating portion 114 extending rearward and downward from the shielding portion 108, an arm portion 116 extending forward and upward from the shielding portion 108, and a protruding portion 118 protruding downward from the lower surface of the arm portion 116. The shielding portion 108, the operating portion 114, the arm portion 116, and the protruding portion 118 are seamlessly and integrally formed. The shielding portion 108, the operating portion 114, the arm portion 116, and the protruding portion 118 are formed of plastic. The operating portion 114 is disposed outside the housing 4. The operating portion 114 is disposed at a position where it can be operated by the index finger of the hand gripping the grip portion 22. The operating portion 114 has a rod shape that curves from top to bottom as it moves from the front to the rear. The width (i.e., the dimension in the left-right direction) of the operating portion 114 is approximately constant from the base end (i.e., the portion connected to the shielding portion 108) to the tip. The thickness (i.e., the vertical dimension) of the operating portion 114 increases from the base end to the tip end. The arm portion 116 is disposed inside the housing 4. A magnet 120 is fixed to the right surface of the arm portion 116. A coil spring 122 is attached around the protruding portion 118. The upper end of the coil spring 122 abuts against the lower surface of the arm portion 116. The lower end of the coil spring 122 abuts against a spring receiving surface 124 provided on the housing 4. The coil spring 122 biases the arm portion 116 upward relative to the housing 4. In other words, the coil spring 122 biases the trigger lever 10 in the counterclockwise direction relative to the housing 4. Note that in the drawings other than FIG. 5, the coil spring 122 is omitted from illustration for simplification.

[0046] Inside the housing 4, a stopper portion 126 is provided that abuts against the upper surface of the arm portion 116 when the trigger lever 10 is rotated counterclockwise. When the trigger lever 10 abuts against the stopper portion 126, the trigger lever 10 is prohibited from rotating further counterclockwise. In this specification, the position of the trigger lever 10 in this state is called the "zero position". When the user does not operate the trigger lever 10, the trigger lever 10 is held at the zero position by the biasing force of the coil spring 122. When the user pulls up the operating portion 114 against the biasing force of the coil spring 122 from the state in which the trigger lever 10 is in the zero position, the trigger lever 10 rotates in the clockwise direction. When the trigger lever 10 is rotated clockwise, the upper surface of the operating portion 114 eventually abuts against the outer surface of the housing 4. When the upper surface of the operating portion 114 abuts against the outer surface of the housing 4, the trigger lever 10 is prohibited from rotating further clockwise. In this specification, the position of the trigger lever 10 in this state is referred to as the "maximum pulled-up position."

[0047] Fig. 6 shows the trigger lever 10 in the zero position. Fig. 7 shows the trigger lever 10 in the maximum raised position. The rotational movement of the trigger lever 10 is limited to a range between the zero position and the maximum raised position. The rotation angle of the trigger lever 10 when rotated from the zero position to the maximum raised position is in the range of 10 degrees to 40 degrees, and is 25 degrees in this embodiment.

[0048] Of the peripheral portion of the trigger through-hole 100 shown in FIG. 4, the portion facing the outer peripheral surface of the shielding portion 108 (see FIG. 5) is called the "facing edge portion 130." Of the facing edge portion 130, the portion positioned above the shielding portion 108 is called the "upper facing edge portion 130a," and the portion positioned below the shielding portion 108 is called the "lower facing edge portion 130b." The upper facing edge portion 130a and the lower facing edge portion 130b each extend substantially parallel to the axis A4. In FIG. 4, the facing edge portion 130 is highlighted by a thick line.

[0049] As shown in Figs. 6 and 7, the facing edge 130 is slightly spaced from the outer circumferential surface of the shielding portion 108. As a result, a gap 132 is provided between the facing edge 130 and the outer circumferential surface of the shielding portion 108. The gap 132 is provided to allow smooth rotation of the trigger lever 10. In this embodiment, the shielding portion 108 has a shape of a revolution body centered on an axis A4. Therefore, the width of the gap 132 between the facing edge 130 and the outer circumferential surface of the shielding portion 108 is maintained constant even when the trigger lever 10 rotates.

[0050] In addition, the portion of the outer periphery of the shielding portion 108 that is exposed to the outside of the housing 4 through the trigger through-hole 100 in the process of the trigger lever 10 rotating from the zero position to the maximum pull-up position is called the "exposed portion 128." Strictly speaking, the "outside of the housing 4" here means "the range from the part where the upper gap 132a is narrowest, through the outside of the housing 4, to the part where the lower gap 132b is narrowest, as viewed from the right." In Figs. 6 and 7, the exposed portion 128 is highlighted by a thick line. The angular range in which the exposed portion 128 exists in the circumferential direction of the axis A4 is within the range of 100 degrees to 160 degrees, and is 130 degrees in this embodiment.

[0051] The sensor board 90 shown in FIG. 8 is a magnetic sensor. The sensor board 90 is fixed to the gear housing 18 (see FIG. 3) by a screw (not shown). The sensor board 90 extends in the front-rear and up-down directions. The sensor board 90 includes a first hall element 134, a second hall element 136, and a third hall element 138. The first hall element 134 is disposed on the left side of the sensor board 90 at the lower part of the sensor board 90. The second hall element 136 is disposed on the right side of the sensor board 90 above the first hall element 134. The third hall element 138 is disposed on the right side of the sensor board 90 above the second hall element 136. The sensor board 90 detects magnetism using the first hall element 134, the second hall element 136, and the third hall element 138, and outputs the detection result to the control device 84. The detection result output to the control device 84 indicates, for example, the strength of magnetism and the direction of the magnetic field.

[0052] The magnet 120 fixed to the right surface of the arm portion 116 faces the left surface of the sensor board 90. When the trigger lever 10 is pulled up, the magnet 120 moves to pass near the first hall element 134. In this case, the magnetism detected by the sensor board 90 (particularly the first hall element 134) varies. The control device 84 (see FIG. 3) can determine the position of the trigger lever 10 relative to the housing 4 or the amount by which the trigger lever 10 has been pulled up, based on the output from the sensor board 90.

[0053] A magnet 140 is fixed to the left surface of the blade holder 36. The magnet 140 faces the right surface of the sensor board 90. When the movable blade 8 rotates, the blade holder 36 also rotates, and the position of the magnet 140 with respect to the sensor board 90 also changes. In this case, the magnetism detected by the sensor board 90 (particularly the second hall element 136 and the third hall element 138) fluctuates. The control device 84 (see FIG. 3) can determine the position of the movable blade 8 with respect to the housing 4 or the amount of rotation of the movable blade 8 based on the output from the sensor board 90.

[0054] (Normal mode of Pruning Shears 2) The following describes the normal operation of the pruning scissors 2. The normal operation here refers to, for example, when a user performs cutting work using the pruning scissors 2. In this embodiment, the operation mode of the pruning scissors 2 at this time is called the normal mode.

[0055] As shown in FIG. 3, when the trigger lever 10 is in the zero position, the control device 84 drives the electric motor 86 so as to hold the movable blade 8 in an open position (also called an open position) relative to the fixed blade 6. When the trigger lever 10 is pulled up from this state, the control device 84 drives the electric motor 86 so as to close the movable blade 8 relative to the fixed blade 6 according to the amount of pulling up the trigger lever 10. Specifically, the control device 84 rotates the movable blade 8 relative to the fixed blade 6 by an amount of rotation according to the amount of pulling up the trigger lever 10. As shown in FIG. 9, when the trigger lever 10 is in the maximum pull-up position, the movable blade 8 is held in a position (also called a closed position) closed relative to the fixed blade 6. When the pull-up operation of the trigger lever 10 is released from this state, the control device 84 drives the electric motor 86 so as to return the movable blade 8 to the open position. In the normal mode, the user can cause the pruning scissors 2 to perform a cutting operation by pulling up the trigger lever 10.

[0056] The control device 84 switches the open position of the movable blade 8 between the first open position and the second open position, which is closer to the first open position, in response to a first operation (e.g., a short press operation) on the adjustment switch 30. By using this function, the user can select an appropriate open position depending on the thickness of the object to be cut. Note that the open position is not limited to the first open position and the second open position, and may be switched to another position.

[0057] (Pruning Shears 2 cutting depth fine adjustment mode) When the second operation (long press operation) of the adjustment switch 30 is performed, the control device 84 switches the operation mode of the pruning scissors 2 to a cutting depth fine adjustment mode for finely adjusting the cutting depth by the fixed blade 6 and the movable blade 8. The cutting depth here means the width of the overlapping portion of the fixed blade 6 and the movable blade 8 when the movable blade 8 is in the closed position. If the cutting depth is shallow, the fixed blade 6 and the movable blade 8 may not be able to completely cut the object to be cut. Although not shown, in the cutting depth fine adjustment mode, the control device 84 deepens the cutting depth each time the trigger lever 10 is pulled up from the zero position. When the trigger lever 10 is pulled up from the zero position a predetermined number of times, the control device 84 returns the cutting depth to the original depth. In the cutting depth fine adjustment mode, the user can adjust the cutting depth to an appropriate depth by pulling up the trigger lever 10. When a third operation (short press or long press) is performed on the adjustment switch 30, the control device 84 switches the operation mode of the pruning scissors 2 to the normal mode.

[0058] (Modification) The configuration in the vicinity of the trigger lever 10 may be applied to other types of working machines, not limited to the pruning scissors 2. The other types of working machines referred to here may be, for example, a grass cutter, shears, a riveter, or a grinder.

[0059] The working machine is not limited to a handy type that the user can hold and carry with one hand, but may be a working machine that is difficult for the user to hold and carry with one hand.

[0060] The work machine may be capable of being fitted with a rechargeable battery pack, in which case the work machine may be operated by power supplied from the battery pack.

[0061] The work machine may be provided with a prime mover other than a brushless motor (for example, a brushed motor, an engine) instead of the electric motor 86.

[0062] The shielding portion 108 may have a shape of a solid of revolution other than a cylindrical shape, for example, the shielding portion 108 may have a truncated cone shape.

[0063] The operating portion 114 may have a shape other than a rod shape. For example, the operating portion 114 may have a shape that is thicker in the circumferential direction of the rotation axis. In this case, the operating portion 114 may straddle the inside and outside of the housing 4 through the trigger through-hole 100. However, in this configuration, there is only one opposing edge portion 130 that faces the outer circumferential surface of the shielding portion 108.

[0064] The shielding portion 108 does not have to be disposed so as to cover substantially the entire trigger through-hole 100. In other words, the shielding portion 108 may be disposed so as to cover only a portion of the trigger through-hole 100.

[0065] The opening direction of the trigger through-hole 100 may be changed as appropriate. For example, the trigger through-hole 100 may open in a direction toward the working unit 12 from a location where the trigger through-hole 100 is provided.

[0066] The left shaft 104 and the right shaft 106 may be separate from the housing 4. In this case, the left shaft 104 and the right shaft 106 may be supported by the housing 4 in a state where they are inserted into the left recess 110 and the right recess 112, respectively. This allows the trigger lever 10 to be rotatable with respect to the housing 4.

[0067] Instead of the left recess 110 and the right recess 112, the shielding portion 108 may have a through hole passing through the inside of the shielding portion 108 in the left-right direction. The left shaft 104 may be inserted into this through hole from the left side of the shielding portion 108. The right shaft 106 may be inserted into this through hole from the right side of the shielding portion 108. In this way, the trigger lever 10 may be rotatable with respect to the housing 4. In addition, the left shaft 104 and the right shaft 106 may be replaced with one shaft passing through the through hole. In this case, the left and right surfaces of the shielding portion 108 may each abut against the periphery of the trigger through hole 100. In this way, the trigger lever 10 may be prohibited from moving in the left-right direction with respect to the housing 4.

[0068] The work machine may be provided with a microswitch instead of the sensor board 90. The microswitch may be disposed in a position where it is pressed by the arm portion 116 of the trigger lever 10 when the trigger lever 10 is rotated clockwise. The control device 84 may determine whether or not the trigger lever 10 has been pulled up based on the output from the microswitch.

[0069] The work machine may include a sensor other than the sensor board 90 and the microswitch (for example, a photo sensor).

[0070] The rotation angle of the trigger lever 10 when the trigger lever 10 is rotated from the zero position to the maximum pulled-up position may be less than 10 degrees or may be more than 40 degrees.

[0071] The angular range in the circumferential direction of the axis A4 over which the exposed portion 128 exists may be less than 100 degrees or may be greater than 130 degrees.

[0072] (Features of the embodiment) As described above, in one or more embodiments, the pruning scissors 2 (an example of a working machine) includes the working unit 12, the electric motor 86 (an example of a prime mover) that operates the working unit 12, the housing 4 that holds the working unit 12 and accommodates the electric motor 86, the trigger lever 10 that spans the inside and outside of the housing 4 via a trigger through-hole 100 (an example of a through-hole) formed in the housing 4 and is operated by a user, a sensor board 90 (an example of a sensor) that is disposed inside the housing 4 and detects the movement of a part of the trigger lever 10 that exists inside the housing 4, and a control device 84 (an example of a control unit) that controls the electric motor 86 according to the detection result of the sensor board 90. The trigger lever 10 is rotatably supported by the housing 4 via a left shaft 104 and a right shaft 106 (an example of a rotating shaft). The trigger lever 10 includes a shielding part 108 having a rotating body shape centered on an axis A4 (an example of a rotating axis of the trigger lever). The peripheral edge of the trigger through-hole 100 includes an opposing edge 130 that faces the outer circumferential surface of the shielding portion 108 .

[0073] The trigger lever 10 can take various positions relative to the housing 4. Depending on the position of the trigger lever 10, it is expected that the gap provided between the peripheral portion of the trigger through hole 100 and the trigger lever 10 will expand. If the gap provided between the peripheral portion of the trigger through hole 100 and the trigger lever 10 expands, foreign matter will easily enter the inside of the housing 4. According to the above configuration, since the shielding portion 108 has a rotating body shape centered on the rotation axis of the trigger lever 10, even if the trigger lever 10 rotates, the distance between the outer circumferential surface of the shielding portion 108 and the opposing edge portion 130 is maintained constant. Therefore, among the gaps provided between the peripheral portion of the trigger through hole 100 and the trigger lever 10, at least the gap 132 provided between the outer circumferential surface of the shielding portion 108 and the opposing edge portion 130 can be kept narrow regardless of the position of the trigger lever 10. Therefore, it is possible to suppress the intrusion of foreign matter into the inside of the housing 4.

[0074] In one or more embodiments, the shielding portion 108 is disposed so as to cover substantially the entire trigger through-hole 100. The trigger lever 10 further includes an operation portion 114 that extends from the shielding portion 108, is disposed outside the housing 4, and is operated by a user, and an arm portion 116 and a magnet 120 (an example of a detection portion) that extend from the shielding portion 108, are disposed inside the housing 4, and are detected by the sensor board 90. The operation portion 114 has a rod shape.

[0075] According to the above configuration, the shielding portion 108 is disposed so as to cover substantially the entire trigger through-hole 100. In this case, the opposing edges 130 (upper opposing edge 130a and lower opposing edge 130b) opposing the outer peripheral surface of the shielding portion 108 are present in two locations so as to sandwich the outer peripheral surface of the shielding portion 108. Therefore, there are two gaps 132 (upper gap 132a and lower gap 132b) that are kept narrow regardless of the position of the trigger lever 10. Therefore, it is possible to prevent foreign matter from entering the inside of the housing 4 over a relatively wide range.

[0076] In one or more embodiments, the trigger through-hole 100 opens in a direction generally opposite to the direction toward the working part 12 from the point where the trigger through-hole 100 is provided.

[0077] When the working unit 12 is operated, it is expected that foreign matter such as dust will scatter in the vicinity of the working unit 12. For this reason, if the trigger through-hole 100 were open toward the working unit 12, the foreign matter scattered as the working unit 12 operates may enter the inside of the housing 4. According to the above configuration, the trigger through-hole 100 opens in a direction substantially opposite to the direction from the location where the working unit 12 is provided toward the working unit 12. For this reason, it is possible to prevent the foreign matter scattered as the working unit 12 operates from entering the inside of the housing 4.

[0078] In one or more embodiments, the sensor includes a magnetic sensor (examples of at least one of a magnetic sensor and a microswitch).

[0079] According to the above configuration, since a general-purpose sensor is used, the configuration of the pruning scissors 2 can be simplified.

[0080] In one or more embodiments, the rotational movement of the trigger lever 10 relative to the housing 4 is limited within a predetermined range of motion. The angle of rotation of the trigger lever 10 when the trigger lever 10 rotates from a zero position (an example of one end of the range of motion) to a maximum raised position (the other end of the range of motion) is less than 45 degrees.

[0081] If the movable range of the trigger lever 10 relative to the housing 4 is excessively large, it becomes bothersome for the user to operate the trigger lever 10. With the above configuration, the movable range of the trigger lever 10 relative to the housing 4 is limited to an appropriate size. This reduces the bothersomeness felt by the user when operating the trigger lever 10.

[0082] In one or more embodiments, the shielding portion 108 is disposed so as to cover substantially the entire trigger through-hole 100. The trigger lever 10 further includes an operating portion 114 extending from the shielding portion 108, disposed outside the housing 4, and operated by a user, and an arm portion 116 and a magnet 120 extending from the shielding portion 108, disposed inside the housing 4, and detected by the sensor board 90. The operating portion 114 has a rod shape. The rotational movement of the trigger lever 10 relative to the housing 4 is limited within a predetermined movable range. When the portion of the outer circumferential portion of the shielding portion 108 that is exposed to the outside of the housing 4 through the trigger through-hole 100 in the process of the trigger lever 10 rotating from the zero position to the maximum pull-up position is defined as an exposed portion 128, the angular range in which the exposed portion 128 exists in the circumferential direction of the axis A4 is 90 degrees or more.

[0083] If the space occupied by the shielding portion 108 inside the housing 4 is large, the housing 4 will become large in size. With the above configuration, most of the shielding portion 108 can be exposed to the outside of the housing 4. This makes it possible to reduce the space occupied by the shielding portion 108 inside the housing 4. As a result, the housing 4 can be made smaller.

[0084] In one or more embodiments, the working portion 12 is configured to perform a cutting operation to cut an object.

[0085] In the above configuration, dust may be generated during cutting by the working unit 12. For this reason, it is considered that a relatively large amount of foreign matter may enter the housing 4 in the environment in which the pruning shears 2 are used. Therefore, the above configuration significantly exerts an effect of suppressing the entry of foreign matter into the housing 4.

[0086] In one or more embodiments, the pruning shears 2 may be a handheld implement that the user can carry in one hand.

[0087] According to the above configuration, the pruning scissors 2 can be easily handled by the user. [Explanation of symbols]

[0088] 2: Pruning shears 4: Housing 6: Fixed blade 8: Movable blade 10: Trigger lever 12: Working section 14: Left housing 16: Right side housing 18: Gear housing 20: Cover housing 22: Grip part 24 :Protective part 26: Operation unit 28: Power switch 30: Adjustment switch 32: Display unit 34: Co-tightening bolt 36: Blade holder 38: Connecting pin 40: Co-tightening nut 42: Lock screw 44: Lock plate 46: O-ring 48: Male thread 50: Fitting part 52: Cylindrical part 54: Fitting hole 56: First through hole 58: Second through hole 60: First cylindrical section 62: Bevel gear 64: 3rd through hole 66: 4th through hole 68: 5th through hole 70: 6th through hole 72: Second cylindrical section 74: Female thread 76: Female thread 78: Male thread 80: 7th through hole 82: Multiple teeth 84: Control device 86: Electric motor 88: Power transmission mechanism 90: Sensor board 92: Connector 94: Gear shaft 96: Bevel gear 98: Opening 100: Trigger through hole 102: Recess 104: Left shaft 106: Right shaft 108: Shielding part 110: Left recess 112: Right recess 114:Operation unit 116: Arm section 118:Protrusion 120: Magnet 122: Coil spring 124: Spring bearing surface 126: Stopper part 128:Exposed part 130, 130a, 130b: opposing edges 132, 132a, 132b: gap 134: First Hall element 136: Second Hall element 138: 3rd Hall element 140: Magnet

Claims

1. The work area and, A prime mover for operating the aforementioned work unit, A housing that holds the work section and houses the prime mover, A trigger lever, operated by the user, spans the inside and outside of the housing via a through-hole formed in the housing, A sensor is located inside the housing and detects the movement of the portion of the trigger lever that is located inside the housing. The system includes a control unit that controls the prime mover according to the detection result from the sensor, The trigger lever is rotatably supported in relation to the housing via a rotating shaft. The trigger lever is equipped with a shielding portion having a rotating body shape centered on the rotation axis of the trigger lever, The peripheral edge of the through hole includes an opposing edge that faces the outer circumferential surface of the shielding portion, in a work machine.

2. The shielding portion is positioned to cover substantially the entire through hole. The trigger lever is, An operating section extending from the shielding portion, located outside the housing, and operated by the user, The system further comprises a detection unit extending from the shielding portion, located inside the housing, and detected by the sensor, The operating section has a rod shape, according to claim 1.

3. The work machine according to claim 1, wherein the through hole opens in a direction substantially opposite to the direction toward the work section from the location where the through hole is provided.

4. The work machine according to claim 1, wherein the sensor includes at least one of a magnetic sensor and a microswitch.

5. The rotational movement of the trigger lever relative to the housing is limited to a predetermined range of motion. The work machine according to claim 1, wherein the rotation angle of the trigger lever when the trigger lever rotates from one end to the other end of the movable range is less than 45 degrees.

6. The shielding portion is positioned to cover substantially the entire through hole. The trigger lever is, An operating section extending from the shielding portion, located outside the housing, and operated by the user, The system further comprises a detection unit extending from the shielding portion, located inside the housing, and detected by the sensor, The aforementioned operating part has a rod shape, The rotational movement of the trigger lever relative to the housing is limited to a predetermined range of motion. When the portion of the outer circumference of the shielding portion that is exposed to the outside of the housing through the through hole during the rotation of the trigger lever from one end to the other end of the movable range is defined as the exposed portion, The work machine according to claim 1, wherein the angular range in which the exposed portion exists in the circumferential direction of the rotating shaft is 90 degrees or more.

7. The work machine according to claim 1, wherein the work unit is configured to perform a cutting operation for cutting an object to be cut, or a cutting operation for cutting an object to be cut.

8. The work machine according to any one of claims 1 to 7, which is a handheld work machine that can be carried by the user with one hand.

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