JP2007116956A - Lawn mower - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lawn mower with which grass leaves and powder dust cut by a cutting blade in a reaping apparatus and water attached to the grass leaves are prevented from flowing into a housing and which is safe and hardly causes a trouble. <P>SOLUTION: A motor 18 for operating the cutting blade 4 and a cooling fan 20 for cooling the motor 18 are internally installed in the reaping apparatus 2 equipped with the cutting blade 4. The reaping apparatus 2 is connected to the lower end of a handle 1 and mounted. The reaping apparatus 2 and the external surface of the connection part of the handle 1 are covered with a connection part cover 34. The inlet 57 of air introduced into the reaping apparatus 2 by the cooling fan 20 is formed at a part covered with the connection part cover 34. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lawn mower in which a mowing device includes a cooling fan for cooling a motor.

  Conventional lawn mowers include a lawn mower as disclosed in Patent Document 1, for example. This lawn mower has a cutting device with a cutting blade on the lower surface attached to the tip of the handle, and the cutting blade is operated by driving a motor built in the cutting device while moving the cutting device on the lawn. And it cuts grass and branches on the ground.

By the way, in the lawn mowers as described above, there is a possibility that the motor becomes very hot as the motor is driven, and for this reason, there is a mowing device equipped with a cooling fan for cooling the motor. However, a lawn mower provided with a general cooling fan has an air inlet introduced into the mowing device by the cooling fan on the lower surface of the mowing device provided with the mowing blade. There is a risk of dust, water on the leaves, etc. flowing into the housing, and it is dangerous for grass and dust to flow into the mowing device equipped with a high-temperature motor, and when water enters the mowing device. Cause failure.
JP-A-6-153650

  The present invention has been invented in view of the above-mentioned conventional problems, and can prevent grass, dust, water attached to the grass, etc., mowed with a cutting blade in the reaping device from flowing into the housing, and is safe and faulty. An object of the present invention is to provide a lawn mower that is unlikely to cause a problem.

  In order to solve the above problems, a lawn mower according to the present invention includes a mowing device 2 provided with a mowing blade 4 and a motor 18 that operates the mowing blade 4 and a cooling fan 20 that cools the motor 18, and the mowing device. 2 is connected to the lower end of the handle 1 and attached, the outer surface of the connection portion between the cutting device 2 and the handle 1 is covered with the connection portion cover 34, and the cutting device 2 is covered by the cooling fan 20 on the portion covered with the connection portion cover 34. An air inlet 57 for air introduced into the inside is formed.

  By forming the air inlet 57 in the portion covered with the connection portion cover 34 away from the ground in this way, the leaves and dust mowed by the cutting blade 4 when the cooling fan 20 rotates, water attached to the grass, etc. Inflow into the housing 3 can be prevented.

  Further, a cylindrical connection cover 34 surrounding the outer periphery of the connection portion between the reaping device 2 and the handle 1 is attached to the reaping device 2, and a communication port 59 is formed at a position overlapping the connection portion cover 34 on the outer surface of the reaping device 2. It is also preferable that the intake port 57 communicates with the reaping device 2 via the communication port 59.

  In this case, since the communication port 59 overlaps with the connection portion cover 34 of the housing 3, the grass, dust, rainwater, etc. that have risen at the time of cutting by the portion covering each communication port 59 of the connection portion cover 34 from the communication port 59. Can be prevented.

  The connecting portion cover 34 has a cylindrical shape formed by connecting a pair of halved cylindrical bodies 35a and 35b, and is connected to the cylindrical connecting tube portion 44 constituting the lower end portion of the handle 1 from the reaping device 2. The protruding insertion part 42 is inserted, the connection cylinder part 44 is sandwiched between the pair of half cylinders 35a, 35b, and the fixing tool 46 inserted from the one half cylinder 35a, 35b is connected to the connection cylinder part 44. And the reinforcing rib 51 protruding from the inner surface of the half tubular bodies 35a and 35b and connected to the outer peripheral surface of the insertion section through the insertion portion 42 and fixed to the other half tubular bodies 35a and 35b. It is also preferable to sandwich the cylindrical portion 44.

  In this case, the three members of the connection portion cover 34, the insertion portion 42, and the connection tube portion 44 can be firmly fixed and integrated by the fixing tool 46. Moreover, the half cylinders 35a and 35b can be reinforced by the rib 51, and the three members can be firmly fixed and integrated with the connection portion cover 34, the insertion portion 42, and the connection tube portion 44.

  According to the present invention, it is possible to prevent grass and dust mowed by the cutting blade when the cooling fan rotates, water attached to the grass and the like from flowing into the housing, ensuring safety and preventing failure.

  Hereinafter, the present invention will be described based on embodiments shown in the accompanying drawings. As shown in FIGS. 2 and 3, the lawn mower according to the present embodiment includes a long handle 1 and a mowing device 2 attached to the tip of the handle 1.

  The outer shell of the reaping device 2 is constituted by a hollow housing 3, and a cutting blade 4 is provided on the lower surface side of the front portion of the housing 3. The cutting blade 4 is composed of a disk-shaped fixed blade 5 and a movable blade 6. The movable blade 6 is rotatably supported on a mounting shaft 7 that protrudes downward from the front portion of the housing 3, and a plurality of blade portions 9 (see FIG. 4) are formed on the outer periphery of the movable blade 6. The fixed blade 5 positioned below the movable blade 6 has a large number of blade portions 65 formed in a comb shape on the outer periphery thereof. The fixed blade 5 is fixed to the tip surface of the mounting shaft 7 with a screw tool 8. The screw 8 projects a small-diameter male screw portion 15 having a smaller diameter than the large-diameter male screw portion 14 from the large-diameter male screw portion 14, and the small-diameter male screw portion 15 passes through the center portion of the fixed blade 5 to the screw hole 13 of the mounting shaft 7. Screwed.

  A metal or synthetic resin blade bottom cover 12 is disposed below the fixed blade 5, and the blade bottom cover 12 covers the central portion of the fixed blade 5 from below. The blade bottom cover 12 has a circular dish shape with the outer peripheral edge inclined upward, and the female screw portion 11 projecting upward from the center portion of the blade bottom cover 12 is screwed onto the large-diameter male screw portion 14 of the screw tool 8. It is attached to the lower surface side of the fixed blade 5 by wearing. A flat smooth surface portion 16 is formed on the lower surface of the blade bottom cover 12, and the cutting device 2 can be moved smoothly by grounding and sliding the smooth surface portion 16 on the grass. Further, as shown in FIG. 4, the blade bottom cover 12 is formed with a plurality of concave portions 17 recessed upward in the circumferential direction so that a portion between the concave portions 17 can be easily grasped with a finger, thereby The cover 12 can be easily attached and detached.

  As shown in FIG. 3, a motor 18 for operating the cutting blade 4 is provided at the rear of the housing 3. An output shaft (not shown) of the motor 18 is connected to the movable blade 6 via a transmission mechanism portion composed of a plurality of gears and the like that are supported by a gear case 19 in the housing 3, and rotation of the output shaft of the motor 18. Is transmitted to the movable blade 6 via the transmission mechanism, and the movable blade 6 can be rotated.

  A cooling fan 20 that cools the motor 18 is provided in the rear part of the housing 3. The cooling fan 20 is a centrifugal fan that discharges air introduced in the axial direction outward, and is disposed behind the motor 18. The cooling fan 20 is coaxially connected to the output shaft of the motor 18, and the cooling fan 20 can be rotated simultaneously with the operation of the cutting blade 4 by driving the motor 18.

  The handle 1 includes a grip 21 bent in an L shape and a cylindrical pole 22 projecting obliquely downward and forward from the tip of the grip 21.

  The grip 21 is a grip portion 23 that is gripped by a hand at a rear portion in a substantially horizontal direction. A push-type switch handle 24 is provided on the lower surface of the grip portion 23 as an operation portion. The grip portion 23 includes a spring 25 for applying a spring force to the switch handle 24, and the spring 25 urges the switch handle 24 in a direction in which the switch handle 24 always protrudes. A switch body 26 operated by a switch handle 24 is housed in the grip portion 23, and a power cord 27 introduced from the rear end of the grip 21 is connected to the switch body 26. The switch body 26 is electrically connected to the motor 18 through a conductive cord 28. The conductive cord 28 is led out from the grip 21 to the outside, and is then introduced into the housing 3 from a rear portion of a protruding portion 29 protruding upward from the housing 3 which will be described later, and is connected to the motor 18 within the housing 3. A breaker 30 is provided in the middle of the conductive cord 28 in the grip 21, and an overcurrent is prevented from flowing through the motor 18 when the breaker 30 winds grass around the movable blade 6, for example. Further, a lock button 31 is provided on the grip portion 23 of the grip 21, and the switch handle 24 can be operated only when the lock button 31 is pushed. That is, the motor 18 can be driven by pushing the lock button 31 and holding the gripping part 23 in this state and pushing the switch handle 24 toward the gripping part 23 side. Further, by releasing the force in the pushing direction to the switch handle 24, the motor 18 is stopped and the operation of the cutting blade 4 can be stopped. When the push-in state of the lock button 31 is released, the switch handle 24 cannot be pushed in, thereby restricting the operation of the motor 18 and the cutting blade 4.

  Further, as shown in FIG. 5, a connecting portion cover 34 is provided at the connecting portion between the handle 1 and the reaping device 2 so as to cover the outer periphery of the same portion. The connection part cover 34 is a cylindrical thing comprised by abutting the both ends of the circumferential direction of a pair of half cylinders 35a and 35b. A plurality of cylindrical bosses 36a, 36b are protruded inward from the inner surfaces of the respective half cylinders 35a, 35b so as to be integral with the half cylinders 35a, 35b. In addition, a plurality of reinforcing ribs 37 are formed on the inner surfaces of the half cylinders 35 a and 35 b so as to be integrated with the half cylinders 35 a and 35 b and along the circumferential direction of the half cylinder 35. As shown in FIG. 6, one end of each of the bosses 36 a and 36 b of one half cylindrical body 35 a opens to the outer surface side of the half cylindrical body 35 a, and serves as a fixing tool insertion hole 38. Moreover, the hole of each boss | hub (not shown) of the other half cylinder 35b is a female screw hole which formed the internal thread in the inner surface.

  In addition, an arbitrary boss (in the illustrated example, two bosses 36a provided side by side in the axial direction of the connecting portion cover 34 on the front part of the upper part of each half cylinder 35) is provided from the inner surface of each half cylinder 35a, 35b. A boss protection part 39 is provided so as to surround. Each boss protection part 39 is constituted by an arcuate part 40 located on both outer sides of the corresponding boss 36 a in the axial direction of the cylindrical connection part cover 34. Each arcuate portion 40 is formed in an arc shape that protrudes outward in the radial direction of the boss 36a, and both ends in the circumferential direction are integrally connected to the outer peripheral surface of the boss 36a. Thus, a buffering gap 41 is formed between the circumferential central portion of each arcuate portion 40 and the outer peripheral surface of the boss 36a.

  Further, as shown in FIG. 5, a protruding portion 29 protrudes obliquely upward and rearward from the front center of the upper surface portion of the housing 3. The conductive cord 28 is introduced into the housing 3 from the upper surface of the rear portion of the protruding portion 29. In addition, an insertion portion 42 that protrudes rearward and obliquely upward is provided on the upper portion of the front portion of the protrusion portion 29. Through holes 43a and 43b penetrating in the left-right direction are formed at positions corresponding to the bosses 36a and 36b of the protruding portion 29 provided with the insertion portion 42. The through-holes 43a and 43b are formed at two locations with a space in the protruding direction of the insertion portion 42 and the lower portions of the front portion and the rear portion of the protruding portion 29, respectively. The shape of the through hole 43 a corresponding to the boss 36 a provided with the boss protection portion 39 is a shape that matches the outer shape of the boss protection portion 39. The shape of the through hole 43b corresponding to the boss 36b not provided with the boss protection part 39 is a shape that matches the outer shape of the boss 36b.

  In addition, fitting holes 45 are formed on both side surfaces of the connecting tube portion 44 constituting the lower end portion of the cylindrical pole 22. The fitting holes 45 are provided at positions corresponding to the bosses 36 a, that is, the fitting holes 45 are provided at two positions with a gap in the axial direction of the connecting tube portion 44. The shape of the fitting hole 45 is a shape that matches the outer shape of the corresponding boss protection part 39.

  When the connection portion cover 34 is attached to the connection portion between the handle 1 and the reaping device 2, it is performed as follows. First, the insertion portion 42 of the reaping device 2 is inserted into the connecting tube portion 44 from the lower end of the pole 22 so that the respective fitting holes 45 and the through holes 43a are overlapped. Next, the protruding portion 29 is sandwiched between the pair of halved cylindrical bodies 35a and 35b from both outer sides. At this time, the bosses 36b of the half tubular bodies 35a and 35b are inserted into the through holes 43b and fitted. At the same time, each boss protection part 39 of each half tubular body 35 is inserted into the through hole 45 and the boss protection part 39 is inserted into the through hole 43a, whereby each boss protection part 39 is inserted into the insertion hole 45 and the through hole. Fit into hole 43b and fix. At the same time, the projecting end surfaces of the ribs 37 of the half cylinders 35 a and 35 b are brought into contact with the outer surface of the insertion portion 42. As a result, the protruding portion 29 of the reaping device 2 is entirely covered by the connection portion cover 34 including the pair of halved cylindrical bodies 35a and 35b except for the base end portion (lower edge portion). Then, with the protruding portion 29 sandwiched between the pair of halved cylindrical bodies 35a and 35b in this manner, screws are inserted into the fixing tool insertion holes 38 of the bosses 36a and 36b from the outer surface side of the one halved cylindrical body 35a. Such a fixing tool 46 is inserted, and the fixing tool 46 is screwed into a female screw hole of each boss provided in the other half cylindrical body 35 to connect the pair of half cylindrical bodies 35a and 35b. Thereby, the connection part cover 34 is attached to the connection part of the handle 1 and the reaping device 2 with the connection cylinder part 44 in which the insertion part 42 is inserted between the pair of halved cylindrical bodies 35a and 35b being sandwiched from both sides. .

  In this attached state, the connection tube portion 44 of the handle 1 is sandwiched between the insertion portion 42 and the half tubular bodies 35a and 35b by the fastening force of the fixing tool 46. Here, the connection tube portion 44 is held inside by the insertion portion 42 and the outside is held by the connection portion cover 34, and the pair of halved cylindrical bodies 35 a and 35 b penetrate the insertion portion 42 and the connection tube portion 44. Since they are connected by the fixing tool 46, the three members of the connection part cover 34, the insertion part 42, and the connection cylinder part 44 are firmly fixed and integrated by the fixing tool 46. In addition, since the boss protection portions 39 of the half tubular bodies 35a and 35b are fitted into the fitting holes 45 of the connection cylinder portion 44, the connection cylinder portion 44 is firmly fixed so as not to come out of the insertion portion 42. . Further, since the buffer gap 41 is formed between each arcuate portion 40 of the boss protection portion 39 and the boss 36a as described above, the direction in which the connection tube portion 44 of the handle 1 is pulled out from the insertion portion 42 or the insertion portion Even if a strong force is applied in the direction of insertion into 42, this force is unlikely to act on the boss 36a. As a result, when a force is applied from the connecting tube portion 44 to the boss 36a, the boss 36a or The insertion part 42 and the connecting cylinder part 44 are prevented from being deformed or damaged.

  Further, as shown in FIG. 7, a cover 47 is also provided at a connecting portion between the grip 21 and the pole 22. The cover 47 on the grip 21 side is also composed of a pair of halved cylindrical bodies 48a and 48b, like the connection portion cover 34 on the cutting device 2 side. That is, each of the halved cylindrical bodies 48a and 48b constituting the cover 47 on the grip 21 side has a plurality of bosses 49a and 49b and a boss protection part 50 surrounding an arbitrary boss 49a in the same manner as the connection part cover 34 on the cutting device 2 side. A reinforcing rib 51 is provided. Also, the protruding portion 52 protruding obliquely downward and forward from the gripping portion 23 is provided with the same insertion portion 53 and through holes 54a and 54b as the reaping device 2, and constitutes the upper end portion of the cylindrical pole 22 A fitting hole 56 similar to that of the connecting tube portion 44 of the pole 22 is formed in the connecting tube portion 55 to be formed. The attachment of the cover 47 on the grip 21 side is performed in the same manner using the fixing tool 46 in the same manner as the attachment of the connection portion cover 34 on the reaping device 2 side, and the description thereof will be omitted.

  When the lawn mower is used, for example, after adjusting the length of the pole 22, the gripping part 23 of the grip 21 is gripped by the hand to slide the mowing device 2 on the lawn, and the switch handle 24 is operated to operate the motor. 18 is driven. When the motor 18 is driven in this way, the movable blade 6 is rotated around the mounting shaft 7, whereby the grass and branches that are drawn between the blade portions 65 of the fixed blade 5 rotate with the blade portion 65 of the fixed blade 5. Clamp it with the blade portion 9 of the movable blade 6. Here, since the blade bottom cover 12 is provided in this example, the height position of the movable blade 6 can be kept constant by the height of the blade bottom cover 12, and the length of the turf can be made constant. At the time of lawn mowing, the cooling fan 20 rotates simultaneously with the operation of the cutting blade 4, and the cooling fan 20 can cool the motor 18 by applying air.

  Here, the air inlet 57 of the air introduced into the reaping device 2 by the operation of the cooling fan 20 described above is formed in a portion covered with the connecting portion cover 34 as shown in FIGS. Specifically, as shown in FIG. 9, the connection portion cover 34 is attached so that the entire circumference of the lower edge is located slightly above the base end of the protruding portion 29 of the housing 3. An air inlet 57 is formed by a gap 58 formed between the housing 3 and the upper surface of the housing 3. In this example, the air inlet 57 is formed between the lower edge of the connection portion cover 34 and the outer surface of the housing 3. However, holes and notches are formed in the connection portion cover 34 and these holes and notches are formed in the air inlet 57. It shall be good.

  As shown in FIG. 5, a plurality of communication ports 59 penetrating the housing 3 are formed on both sides of the protruding portion 29 of the housing 3. Each communication port 59 is located slightly above the base end of the protrusion 29. Each communication port 59 is located above the intake port 57 as shown in FIG. 9, and each communication port 59 is formed at a position overlapping the connection portion cover 34 when viewed from the outer surface side of the connection portion cover 34.

  Moreover, as shown in FIG. 6 etc., the recessed part 60 is formed in the part which opposes each communicating port 59 of the inner surface of each half cylinder 35a, 35b which comprises the connection part cover 34, and each recessed part 60 is an inside. It opens only in the direction and below. As a result, the intake port 57 is formed in the housing 3 through the intake passage 61 formed between the inner surface of the protrusion 29 of the housing 3 and the rear surface of the concave portion 60 of the cover, and the communication ports 59 in this order. Communicating with

  Further, as shown in FIG. 5, a plurality of exhaust ports 62 are formed on both sides of the rear portion of the housing 3. Each exhaust port 62 is located outside the cooling fan 20. Each exhaust port 62 communicates with the above-described communication port 59 through a vent passage 63 formed in the housing 3 as shown in FIG. 3, and the motor 18 and the cooling fan 20 are connected to the vent passage 63 from the upstream side. They are arranged in order. The space between the lower surface of the housing 3 on which the cutting blade 4 is provided and the outer peripheral portion of the movable blade 6 is hermetically sealed by a seal member 64, so that when the cooling fan 20 is operated, the lower surface of the housing 3 The air is prevented from flowing into.

  Therefore, when the motor 18 is driven to rotate the cooling fan 20, air outside the reaping device 2 is sucked from the intake port 57, and this air passes through the intake passage 61 and the communication port 59 in the air passage 63 in the housing 3. Then, the air is discharged from the exhaust port 62 through the motor 18 and the cooling fan 20.

  As described above, in the present invention, the air inlet 57 is formed in the connection portion cover 34 located at a position away from the cutting blade 4, so that the grass, dust, and grass cut by the cutting blade 4 when the cooling fan 20 rotates. It is possible to prevent water or the like from flowing into the housing 3. In addition, each communication port 59 through which the air flowing in from the intake port 57 passes is formed at a position overlapping the connection portion cover 34 of the housing 3, so that It is also possible to prevent dust, rainwater, and the like from flowing into the housing 3 from each communication port 59. Moreover, since the intake port 57 is formed by a gap between the lower edge of the connection portion cover 34 and the upper surface of the housing 3, the appearance is not noticeable and good.

It is an example of an embodiment of the invention and is a side view of a connection portion between a cutting device and a handle. It is a whole perspective view of a lawn mower same as the above. It is a sectional side view of a lawn mower same as the above. It is a bottom view of a lawn mower same as the above. It is a disassembled perspective view of the connection part of a cutting device same as the above and a handle. It is the perspective view seen from the inner surface side of one half cylinder body of a cover same as the above. It is a disassembled perspective view of the connection part of a pole and a grip same as the above. It is the perspective view seen from the inner surface side of one half cylinder body of the grip side cover same as the above. It is AA sectional drawing of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Handle 2 Cutting device 4 Cutting blade 18 Motor 20 Cooling fan 34 Connection part cover 35a Half cylinder body 35b Half cylinder body 42 Insertion part 44 Connection cylinder part 57 Inlet 59 Communication port

Claims (3)

  A mowing device provided with a mowing blade is equipped with a motor for operating the mowing blade and a cooling fan for cooling the motor, the mowing device is connected to and attached to the lower end of the handle, and the outer surface of the connecting portion between the mowing device and the handle is attached. A lawn mower characterized in that it is covered with a connection portion cover, and an air intake port for air introduced into the mowing device by the cooling fan is formed in a portion covered with the connection portion cover.   A cylindrical connection cover that surrounds the outer periphery of the connection portion between the reaping device and the handle is attached to the reaping device, a communication port is formed at a position overlapping the connection portion cover on the outer surface of the reaping device, and the intake port is connected to the communication port. The lawn mower according to claim 1, wherein the lawn mower is communicated with the mowing device.   The connecting portion cover is a cylindrical member formed by connecting a pair of halved cylindrical bodies, and an insertion portion protruding from the reaping device is inserted into a cylindrical connecting tube portion constituting the lower end portion of the handle. The connecting cylinder part is sandwiched between the pair of half cylinders, and the fixing tool inserted from one half cylinder is fixed to the other half cylinder through the connection cylinder and the insertion part, The lawn mower according to claim 1 or 2, wherein the connecting cylinder part is sandwiched between a reinforcing rib projecting from the inner surface of the half cylinder and the outer peripheral surface of the insertion part.

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