TW201313115A - Walk-behind mower - Google Patents

Abstract

The present invention is to easily construct an adjusting mechanism capable of adjusting the mowing height. The adjusting mechanism includes a front wheel transmission box (16) for supporting a front end by a front wheel (1) and supporting a front portion of a movable body in a swingable manner around a supporting shaft (Q), a switching operation part (F) for maintaining the swing status of the front wheel transmission box (16). The switching operation part (F) includes an engaging board (82) with a plurality of engaging holes (82A); a locking member (84) to engage with the engaging holes (82A) by means of the elastic pushing force of a latch spring (85), and an unlocking steel wire (86) for operating the locking member (84) toward the direction of leaving the engaging holes (82A).

Description

Lawn mower

The present invention relates to a cutting blade for mowing that is provided with a driving shaft core that is rotated in a longitudinal direction, and a front wheel is provided at a front portion of the body, and a handle extending rearward from the body is provided. The support body for supporting the front wheel is supported by the support body so as to be vertically swingable around the support shaft core in the lateral posture, and the adjustment of the mowing height of the cutting edge is adjusted according to the setting of the swing posture of the support body. Institutional mower.

Further, the present invention relates to a lawn mower having a cutting blade for mowing on a lower end side of a drive shaft that rotates around a drive shaft core in a longitudinal direction, and a grounding body disposed on a lower end side of the drive shaft.

In the above-described lawn mower, Japanese Laid-Open Patent Publication No. 2010-273584 (Patent Document 1) discloses a configuration in which a shaft core supporting an input shaft on the upper end side at a front portion of the movable body is The center is a swinging front wheel gearbox. The front wheel is supported on the front end side of the front wheel transmission case. Patent Document 1 discloses a mechanism for setting a swing amount of a front wheel transmission case by a rotation operation of an operation handle, thereby changing a ground height adjustment of a road surface mowing apparatus.

Further, in the above-described Patent Document 1 (paragraph Nos. [0052] to [0056], and Figs. 18 to 20), the mower described above is provided with the front wheel and the rear wheel. Mobile body There is a road surface cutting device, and a slope cutting device for cutting grasses having a slope surface is provided at a side portion of the mobile body. In the side of the movable body, the side surface of the movable body is provided with a deck for swinging around the axis of the front and rear positions of the side position, and the deck is supported by the deck. The lower end side of the drive shaft is provided with a cutting blade for mowing, and a grounding body is provided on the lower end side of the drive shaft to constitute a slope cutting device. Therefore, the grounding body is grounded on the ground during the work, whereby the height of the cutting edge to the ground can be determined, and the mowing height of the cutting device for the slope can be maintained.

Further, in the above-described Patent Document 1, the slope deck is configured to be swingably supported by a movable body centering on a shaft core in a lateral posture, and the slope cutting device and the slope surface are operated by the operation of the operating lever. The deck is tilted together to perform the adjustment of the mowing height.

In Patent Document 1, in order to perform the adjustment of the swing amount of the front wheel transmission case, the hoisting device that connects the front wheel transmission case is configured to extend the drive screw portion of the hoisting device upward, and the base end hub portion of the operation handle is screwed in Drive the screw section.

In this configuration, it is necessary to have a base end hub portion that is rotatably operated by the operation handle, and a support structure for supporting the operation handle is required, and a drive screw portion screwed to the base end hub portion is required and equipped with the drive. The front wheel transmission case of the screw portion and the like, and thus the number of parts is increased to cause a complicated structure.

Further, the mechanism for adjusting the mowing height disclosed in Patent Document 1 requires the operator to operate the operation handle at the front position of the mobile body, which also causes trouble to the operator.

In addition, as shown in the description of the patent document 1, when the height is adjusted in a state in which the slope cutting device is integrally swung, the movable portion is likely to be large, and the adjustment structure is increased in size. In addition, the adjustment structure of the patent document 1 is configured such that the slope cutting device is tilted in a state where the grounding body is grounded, and thus the amount of adjustment of the mowing height cannot be greatly changed.

In the lawn mower of Patent Document 1, the mowing height is highest in a state where the rotation locus around the cutting edge is on an imaginary plane parallel to the slope surface (ground), and the mowing height is high in a state where the rotation locus is largely inclined. It is low, so if the mowing height is set to be high, it is necessary to replace the grounding body with a grounding body that protrudes downward from the cutting edge and has a large amount of protrusion, which is relatively labor-intensive.

One of the objects of the present invention is to easily configure an adjustment mechanism capable of adjusting the height of mowing.

Further, another object of the present invention is to provide a lawn mower having a mowing height adjusting mechanism that determines the mowing height by the grounding of the grounding body, and an adjustment mechanism capable of greatly adjusting the mowing height.

The lawn mower according to the present invention is configured such that the machine body includes a cutting blade for cutting the blade core in a longitudinal direction, and a front wheel is provided at a front portion of the body, and the body is provided from the body toward Extend rearward The handle is provided, and the support body for supporting the front wheel is supported by the support body in a lateral posture, and is supported by the body up and down, and the cutting edge is adjusted according to the setting of the swing posture of the support body. Mowing height adjustment mechanism, The adjustment mechanism includes a switching operation unit that can freely convert the posture of the support body into a fixed state in which the posture of the support body is fixed, and a release state in which the posture of the support body is allowed to swing freely. When the operation unit sets the support body in the released state, the front wheel is freely displaced downward or upward according to the setting of the lift height of the front portion of the body, and the displacement allows the swing of the support body.

According to this configuration, the support unit is set to the released state by the switching operation unit, and the amount of lift of the front portion of the body is adjusted by the operation of the handle, so that the support body can be swinged freely to bring the front wheel to the ground. After the support body is swung as described above until the height of the cutting edge and the ground reaches the value corresponding to the mowing height, the support body is set to a fixed state by the switching operation portion, thereby maintaining the height of the cutting edge and the ground to the ground. The height of the mowing is adjusted.

As a result, it is not necessary to use a large number of components, and it is also possible to easily configure an adjustment mechanism capable of adjusting the mowing height without using a high-precision configuration.

In the present invention, the switching operation unit may include a plurality of engaging portions that correspond to the plurality of swinging postures of the support body, and the one of the engaging portions that are engaged with the plurality of engaging portions to hold the support In the lock body of the swinging posture of the body, the switching operation unit further includes an operation unit for performing switching between the engagement portion and the lock body.

According to the above configuration, the operation using the operation unit is capable of being engaged The engagement of the unlocking body is released, and after the release, one of the plurality of engaging portions is selected by the operation of the operating unit to engage the locking body, and the support can be set to one of the plurality of swinging postures. This configuration is such that the lock body is engaged with the engagement portion, so that the swing posture can be firmly maintained.

In the present invention, the plurality of engaging portions may be configured to include an engaging plate that has a plurality of engaging holes disposed in an arcuate region centering on the support shaft core, and the locking portion The body is formed by a locking member that is detachable from the engaging hole, and the switching operation portion has a lock spring that can obtain a spring force to engage the locking member with the engaging hole, and the operating unit has a working force to cause the locking member The operation wire that is detached from the engagement hole is provided with the lock release lever that acts to move the lock member away from the engagement hole through the operation wire.

According to the above configuration, since the engaging hole of the engaging plate is engaged with the locking member by the elastic thrust of the lock spring, the locked state can be surely maintained. Further, since the lock member is disengaged from the engagement hole by the operation of the operation wire from the handle, the operator can adjust the mowing height without standing at the front of the body.

In the present invention, the body may include a motive portion, and the support body may include a transmission mechanism that transmits a driving force from the motive portion to the front wheel.

According to the above configuration, the driving force of the driving force can be obtained by transmitting the driving force of the motive portion from the transmission case to the front wheel.

The lawn mower according to the present invention is a driving core in a longitudinal posture The lower end side of the drive shaft that rotates at the center is provided with a lawn cutting blade, and a lawn mower is disposed on the lower end side of the drive shaft. a displacement shaft that is movable integrally with the drive shaft along a drive shaft core of the drive shaft in a state of being embedded in the drive shaft, and the grounding body is provided at a lower end of the shift shaft. An adjustment unit that adjusts the amount of protrusion of the shift shaft downward is provided.

According to this configuration, the transmission adjusting unit moves the shift shaft along the drive shaft core, thereby changing the relative distance between the grounding body provided at the lower end of the shift shaft and the cutting edge of the drive shaft, and can be arbitrarily set. Mowing height. In particular, in this configuration, the relative movement amount of the drive shaft and the shift shaft can be easily increased, and the movable portion is smaller than the configuration in which the drive shaft and the cutting edge are integrally inclined as shown in Patent Document 1. It is also possible to suppress the increase in size.

Therefore, although the lawn mower is a lawn mower equipped with an adjustment mechanism that determines the mowing height by the grounding of the grounding body, an adjustment mechanism capable of greatly adjusting the mowing height can be constructed.

In the present invention, the drive shaft is rotatably supported by the casing, and is formed in a tubular shape having a hole through which the displacement shaft is to be inserted, and an inner circumference of the hole portion and the displacement shaft. Between the outer periphery, a transmission means for allowing the shift shaft to move up and down with respect to the drive shaft and integrally rotating the drive shaft and the shift shaft is formed.

According to the above configuration, when the shift shaft is inserted into the hole portion of the cylindrical drive shaft, and the shift shaft is moved along the drive shaft core with respect to the drive shaft, the inner circumference and the shift of the hole portion of the drive shaft are formed. The transmission between the periphery of the bit axis will allow In this movement, the rotational driving force of the drive shaft is transmitted to the shift shaft via the transmission means, and the drive shaft and the shift shaft are integrally rotated. In this way, in order to transmit the driving force of the drive shaft to the shift shaft, even if a complicated transmission system such as a gear type or a chain type is not provided, the configuration of the transmission means can be simplified by using a spline shaft or an angular shaft.

In the present invention, the adjustment unit may include an engagement member that engages with the shift shaft in a state in which the shift shaft is allowed to rotate, and an operation shaft that is rotatable in a posture parallel to the drive shaft core. And a screw portion that moves the engaging member along the driving shaft core during the operation of the operating shaft.

According to the above configuration, the rotation operation is performed on the operation shaft, and the engagement member can be moved along the drive shaft core by the force from the screw portion, and the shift shaft to which the engagement member is engaged can be moved along the drive shaft core. Further, since the adjustment portion is provided with the screw portion, it is possible to perform a small amount of adjustment, and the screw portion does not rotate even when an external force acts from the displacement shaft in the direction of the drive shaft core, and the set mowing can be maintained. height.

In the present invention, the body may be provided with a wheel and a motive portion to be in contact with the ground, and a base end of the casing that is swingably supported at a side portion of the body at a side portion of the body may be oscillated. The drive shaft is supported by the casing, and the drive shaft is provided with a transmission mechanism for transmitting a driving force from the motive portion.

According to the above configuration, since the base end portion of the casing that swings freely around the pivot axis of the front and rear postures is supported on the side portion of the body, the rotation locus of the cutting edge is parallel to the slope surface. Posture tolerance The swing of the casing, whereby the grass on the slope can be cut off. As described above, even if the casing that is configured to be swingable is provided with the drive shaft, or the shift shaft that can freely adjust the amount of protrusion that protrudes downward from the drive shaft, the grounding body is provided, so that the swing of the casing can be eliminated. The posture maintains the mowing height at the set value.

[Best Embodiment of the Invention]

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[All composition]

As shown in FIGS. 1 to 4, the lawn mower is configured such that the upper part of the mobile body A that travels on the single front wheel 1 and the single rear wheel 2 is provided with the engine 4, the fuel tank 5, and the muffler as the motive parts. The device 6 and the like are provided with a pair of left and right steering handles 7 extending from the rear position of the movable body A, and the lower side of the movable body A is provided with a grass to be cut off from the road surface. The road surface cutting device B is provided with a slope cutting device C for cutting the grass on the slope surface on the left side portion of the mobile body A. In the lawn mower, an electric motor that is activated by a power source from a battery may be provided to constitute a motive unit.

The body frame 10 of the mobile body is provided with a center casing 11, and a road surface cutting device B having a center blade 12 (an example of a cutting edge) is disposed below the center casing. Further, a side casing 13 is provided on the left side portion of the body frame 10, and is disposed on the lower side of the inside of the side casing 13 The cutting device C is used for the slope of the side cutting edge 14. As shown in FIGS. 5 and 6, the side casing 13 is swingably supported by the body frame 10 centering on the swing axis P along the posture in the front-rear direction of the movable body A. In order to allow the side casing 13 to swing, a part of the left end of the center casing 11 is formed into a cylindrical shape centering on the swinging shaft core P, and a part of the right end of the side casing 13 is formed into a swinging shaft. The core P has a cylindrical shape at the center, and is pivoted by a pivot shaft 15 that penetrates the internal space of the tubular portions.

The front wheel 1 is rotatably supported by a lower portion of the front end side of the wheel transmission case 16 as a support body, and the rear wheel 2 is rotatably supported at a lower portion of the rear wheel transmission case 17. The upper portion of the mobile body A is provided with a travel drive mechanism Dr that transmits the driving force of the engine 4 to the rear wheel transmission case 17 and the front wheel transmission case 16 to transmit the driving force to the front wheel 1 and the rear wheel 2. Further, in the region of the upper surface of the center casing 11 and the upper surface of the side casing 13, the cutting force for transmitting the driving force from the engine 4 to the road surface cutting device B and the slope cutting device C is provided. Grass drive mechanism Dc.

Since the side casing 13 is slidably supported at the side position of the mobile body A, when the mowing operation is to be performed in an environment where the slope on the left side of the mobile body A exists, the side casing 13 is Since the slope cutting device C can be swung into a posture along the slope surface as shown in Fig. 6, the grass on the slope surface can be cut. Further, the center blade 12 of the road surface cutting device B and the side blade 14 of the slope cutting device C are arranged in a positional relationship in which the rotation trajectories are overlapped. However, as shown in Fig. 4, the center blade 12 and the center blade 12 are provided. The rotation phase of the side cutting edge 14 is shifted by 90 degrees, so that the central cutting edge 12 and the side cutting edge 14 can be kept out of contact. The structure is rotatable. Further, the mowing drive mechanism Dc is configured to allow the swing of the side casing 13 to be freely configured as described below.

According to the above configuration, the lawn mower can drive the front wheel 1 and the rear wheel 2 to drive the mobile machine body while driving from the engine 4, and drive the road surface with the driving force from the engine 4. The cutting device B and the slope cutting device C cut the grass on the road surface in the horizontal posture by the road surface cutting device B, and cut the grass on the slope surface with the cutting device C. This performs a mowing operation.

[driving drive mechanism]

As shown in FIG. 2, FIG. 3, FIG. 10, and FIG. 11, the front wheel transmission case 16 includes an input shaft 18 at the upper end portion and a front wheel drive shaft 19 at the lower end portion, and the front wheel drive shaft 19 is coupled to the front wheel drive shaft 19. The front wheel 1 has a chain transmission mechanism incorporated in the front wheel transmission case 16 to transmit the driving force of the input shaft 18 to the front wheel drive shaft 19. A front bracket 20 having a longitudinal posture is provided at a front portion of the body frame 10, and the front bracket 20 supports a front wheel transmission case 16 that is swingable about a support shaft Q that is coaxial with the input shaft 18. The input shaft 18 is provided with an intermediate shaft 21 to be coupled, and an outer end of the intermediate shaft 21 is provided with an input sprocket 22. The front wheel transmission case 16 functions as a center mowing height adjustment mechanism that sets the grass cutting height of the road surface cutting device B in accordance with the setting of the swing posture. The details of the center mowing height adjustment mechanism will be described below.

The rear wheel transmission case 17 includes a driven shaft (not shown) at the upper end portion and a rear wheel drive shaft 25 at the lower end portion. The intermediate output shaft 26 is coupled to the rear wheel 2 at the rear wheel drive shaft 25, and a chain transmission mechanism (not shown) is incorporated in the rear wheel transmission case 17 to transmit the driving force of the driven shaft to the rear wheel drive. Axis 25 and intermediate output shaft 26. The rear wheel transmission case 17 is coupled and fixed to the rear end portion of the body frame 10. As shown in Fig. 2, the same clutch core (not shown) is provided with a running clutch mechanism 27 and an input pulley 28. The running clutch mechanism 27 is a discontinuity that performs a driving force to be transmitted from the input pulley 28 to the driven shaft (not shown).

An outer end of the intermediate output shaft 26 has an output sprocket 29 from which the input sprocket 22 of the front wheel transmission case 16 is wound with an interlocking chain 30 formed of an endless chain. Further, the first output pulley 31A and the input pulley 28 provided in the output shaft of the engine 4 are wound with a transmission belt 32 formed of an endless belt. By providing the front wheel transmission case 16, the rear wheel transmission case 17, and the drive belt 32 for transmitting the driving force of the engine 4 to the rear wheel transmission case 17, the driving force of the rear wheel transmission case 17 can be transmitted. The interlocking chain 30 to the front wheel transmission case 16 can constitute the travel drive mechanism Dr.

The running clutch operating lever 33 (refer to FIG. 10) for operating the running clutch mechanism 27 is provided near the grip 7G on the left side of the operating handle 7, and controls the running clutch mechanism 27 in accordance with the gripping operation of the running clutch operating lever 33. The travel clutch wire 34 is provided between the travel clutch operating handle 33 and the operating arm 27A of the travel clutch mechanism 27. Although not shown in detail in the drawing, the running clutch wire 34 has a structure in which the inner wire can be housed inside the outer wire, and is driven away. The one of the inner wires is connected to one end of the inner wire, and the other end of the inner wire is connected to the operating arm 27A.

With this configuration, as long as the gripping operation of the running clutch operating lever 33 is transmitted through the running clutch wire 34, the running clutch mechanism 27 can be input and the driving force of the engine 4 can be transmitted from the transmission belt 32 to the rear wheel transmission case 17. The transmission causes the rear wheel 2 to drive, so that the driving force synchronized with the drive is transmitted from the interlocking chain 30 to the front wheel transmission case 16, and the front wheel 1 is driven to perform the traveling of the mobile body A.

[Mower grass drive mechanism]

As shown in Figs. 3 to 6, there is provided a center gear case 40 to be disposed at an upper portion of the center casing 11, and a side gear case 41 to be disposed at an upper position of the side casing 13, and is provided with: The driving force output from the drive shaft 42 extending laterally from the center gear box 40 is transmitted to the transmission system of the center cutting edge 12; and the driving force from the driving shaft 42 and the two engaging mechanisms 43 and the expansion and contraction can be freely The driving force of the intermediate transmission shaft 44 is transmitted to the driven shaft 45 of the side gear case 41, and then transmitted from the side gear case 41 to the transmission system of the side cutting edge 4, whereby the mowing drive mechanism Dc can be constructed.

The two engagement mechanisms 43 are joint mechanisms having a function of transmitting a rotational driving force in a bent state, such as a universal joint, and the intermediate transmission shaft 44 is formed by embedding an inner shaft in the outer shaft. The fitting portion is a telescopically movable transmission shaft that can be relatively moved in the direction of the axial direction by a torque transmission using a spline shaft or an angular shaft.

A drive pulley 46 is provided at an outer end position of the drive shaft 42, and a drive belt 47 is wound from a second output pulley 31B provided in an output shaft of the engine 4 to the drive pulley 46, and a tension can be applied to the drive belt 47. Tensioning pulley 48. The tension pulley 48 is rotatably supported by the swing end of the tension arm 49, and the tension arm 49 is swingably supported by the body frame 10. The swinging operation by the tensioning arm 49 constitutes a mowing clutch mechanism for performing the driving force interruption of the driving belt 47.

As shown in Figs. 1 and 3, the mowing clutch operating handle 50 for operating the mowing clutch mechanism is disposed near the grip 7G on the right side of the operating handle 7, and the mowing clutch wire 51 for controlling the mowing clutch mechanism. It is equipped between the mowing clutch operating handle 50 and the tensioning arm 49. The mowing clutch wire 51 has a structure in which the inner wire can be housed inside the outer wire, and the mowing clutch operating handle 50 is connected to one end of the inner wire, and the tension arm 49 is connected to the other end of the inner wire. .

According to this configuration, the mowing clutch mechanism can be input and operated by the mowing clutch wire 51 by the gripping operation of the mowing clutch operating handle 50, so that the driving force of the engine 4 is transmitted from the driving belt 47 to the mowing drive mechanism. Dc realizes driving of the road surface cutting device B and the slope cutting device C. Further, when the slope cutting device C reaches the swinging posture along the slope surface, the angle of the swinging posture can be driven by the bending of the two engaging mechanisms 43 and the expansion and contraction of the intermediate transmission shaft 44. The force is transmitted to the slope cutting device C.

[Pavement cutting device]

The center gear case 40 is provided with the lower case 40A in a posture in which the center case 11 is vertically penetrated, and the lower case 40A supports a center that is rotatable about the center drive axis X in the vertical posture. The drive shaft 55 is provided with a first center bevel gear 56A on the drive shaft 42. The first center bevel gear 56A is disposed such that the driving force of the drive shaft 42 can be transmitted to the upper end of the center drive shaft 55 to be engaged with the first center. The second center bevel gear 56B of the bevel gear 56A is provided at an upper portion of the center drive shaft 55. A support plate 57 is fixed to the lower end of the center drive shaft 55, and a bottom wall portion of the attachment preventing cone 58 is disposed on the lower surface of the support plate 57, and a lower side of the bottom wall portion of the attachment preventing cone 58 is disposed. The center edge 12 of the sheet overlaps, and the center blade 12 and the winding prevention cone 58 are supported on the support by locking the nut 57N fixed to the support plate 57 by a pair of coupling bolts 59 that pass through the upper and lower blades 12 up and down. Board 57.

The wrap preventing cone 58 is formed in a cup shape in which the upper outer diameter is larger than the outer diameter of the lower portion, and the connecting bolts 59 are inserted into the two through holes formed in the bottom wall portion of the wrap preventing cone 58, and are formed in the pair. A coupling bolt 59 is inserted into the two through holes of the two center cutting edges 12. Further, among the two center cutting edges 12, the outer end of the upper center cutting edge 12 is bent to be displaced upward, and the outer end of the lower central cutting edge 12 is zigzag downward.

As described above, the center drive shaft 55 that can transmit the drive force from the mowing drive mechanism Dc and the center blade 12 that is driven by the center drive shaft 55 are provided to constitute the road surface cutting device B.

[Slope cutting device]

As shown in FIGS. 5 to 9 , in the side gear case 41 , the lower support case 41A is disposed such that the lower side case 13 is vertically penetrated, and the lower support case 41A is disposed in the vertical position. The shift shaft 61 and the cylindrical side drive shaft 62 that is externally fitted to the lower end portion of the shift shaft 61 through the spline fitting structure are disposed such that the side drive shaft core Y is located on the same shaft core. The driving force of the driven shaft 45 can be transmitted to the upper end of the shift shaft 61, and the first side bevel gear 63A is fitted to the driven shaft 45 to be engaged with the second side round gear of the first side bevel gear 63A. The 63B is disposed on the same axis as the side drive shaft core Y, and the second side bevel gear 63B is externally fitted to the upper end portion of the shift shaft 61 through the spline fitting structure. The 63B and the shift shaft 61 are relatively moved in the direction of the side drive shaft core Y.

Further, a spline fitting structure formed on the outer surface of the lower portion of the shift shaft 61 and the inner surface of the cylindrical side drive shaft 62 which is externally fitted to the outer surface is a type in which the shift shaft 61 and the side drive shaft 62 are integrally rotated. At the same time, one of the transmission means for relatively moving the shift shaft 61 and the side drive shaft 62 in the direction of the side drive shaft core Y. The transmission means may be configured such that the cross-sectional shape of the lower portion of the shift shaft 61 and the hole-shaped portion of the side drive shaft 62 to be embedded therein is formed into a polygonal shape such as a square shape or the shift shaft 61. The inner surface of the outer and side drive shafts 62 is formed with a groove that is parallel to the side drive axis Y, and is provided with a key or the like to be engaged in the groove.

The side drive shaft 62 is supported by a ball bearing type bearing 64 for supporting the intermediate portion so as to be rotatable relative to the lower support box 41A, and Further, the support plate 57 is fixed to the lower end portion of the side drive shaft 62 in the up-and-down direction. A bottom wall portion of the winding preventing cone 58 is disposed on the lower surface of the support plate 57, and two overlapping side cutting edges 14 are disposed on the lower side of the bottom wall portion of the winding preventing cone 58, and the side cutting edge is added to the side edge The lower side of the 14 is provided with an upper plate 65, and the side nut 14 and the wrap preventing cone 58 and the upper portion are fixed by a bolt 57N fixed to the support plate 57 by a connecting bolt 59 that penetrates the upper and lower blades 14 up and down. The plate 65 is supported on the support plate 57.

A pair of wrapping preventing pieces 65A are formed in the upper plate 65 in a downwardly protruding posture, and the wrapping preventing piece 65A is formed with a concave portion 65B having a small width at the intermediate position in the vertical direction at the side end.

The lower end of the shift shaft 61 protrudes downward from the lower end of the side drive shaft 62. The lower plate 70 is fixed to the lower end by a fixing bolt 71, and the grounding body 72 is coupled to the lower side of the lower plate 70 by a plurality of retaining bolts 73. Further, the retaining bolt 73 is fixed to the grounding body 72, and the retaining bolt 73 is locked by the retaining nut 74 disposed on the upper surface side of the lower plate 70.

In the lower plate 70, a pair of wrap-preventing bodies 70A are formed in a posture that protrudes upward, and the wrap-preventing body 70A is formed with a concave portion 70B having a small width at an intermediate position in the vertical direction. The relative relationship between the pair of wrap-preventing sheets 65A and the pair of wrap-preventing bodies 70A is set so that a straight line connecting the pair of wrap-preventing preventing bodies 70A can be connected, and one of the upper plates 65 is connected to the roll The straight line with the preventing piece 65A is regarded as being orthogonal to the plane, and the wrapping preventing bodies 65A, 70A can be configured to prevent the grass or the like from being wound around the shift shaft 61.

Further, the concave portion 65B formed in the pair of attachment preventing pieces 65A, and the concave portion 70B formed in the pair of attachment preventing members 70A are formed so as not to obstruct the head or the holding nut of the coupling bolt 59. 74 operation of tools such as wrenches.

The grounding body 72 is a bowl-shaped molded product whose plane is regarded as a circular shape and which is more convex toward the center portion. When the grass cutting operation is performed, the center portion of the grounding body 72 contacts the slope surface (ground), thereby determining the slope. The distance between the face and the side cutting edge 14 makes it possible to adjust the mowing height. Further, the grounding body 72 is integrally rotated with the shift shaft 61, and is rotated in a grounded state to achieve smooth slidability on the slope surface (ground). A side mowing height setting mechanism for determining the amount of protrusion of the grounding body 72 downward is provided in the vicinity of the side gear case 41, and the details of the side mowing height setting mechanism will be described below.

[Side mowing height adjustment mechanism]

As shown in FIGS. 7 and 8, the operation shaft 77 that is parallel to the side drive shaft Y is provided in the side gear case 41 in a state in which the upper end thereof protrudes upward from the upper surface of the side gear case 41. An annular groove portion is formed on the outer periphery of the shift shaft 61 at the center position, and the annular groove portion is provided with a shifting device 78 that is engaged with the engaging member through the bearing 78A. A screw portion 77A is formed at a lower end portion of the operation shaft 77, and a screw portion of the shifting device 78 is screwed to the screw portion 77A, so that the fork portion of the shifting device 78 can be engaged with the bearing 78A. A rotation operation arm 79 is provided at an upper end of the operation shaft 77, and an adjustment lever 79A is provided at an outer end of the rotation operation arm 79. As mentioned above The adjusting portion for adjusting the amount of protrusion of the shift shaft 61 downward can be formed by the shaft 77 and the shifting device 78 that adjusts the vertical position by the screw type.

Based on the above configuration, when the operator grasps the adjustment knob 79A to rotate the operation shaft 77, the shifting device 78 moves in either of the up and down directions, which causes the shift shaft 61 to move up and down, changing the grounding body 72 and the side. The relative distance between the upper and lower blades 14 allows the mower height to be adjusted.

When the grass is cut by the cutting device C for the slope, the slope cutting device C swings in the downward direction about the swing axis P due to its own weight, so that the grounding body 72 can be kept in contact with the grounding body 72. The state of the slope (ground). Based on the grounding position of the grounding body 72, the distance from the grounding position of the grounding body 72 to the imaginary plane in which the rotational trajectory of the side cutting edge 14 exists in the direction of the side driving axis Y is the mowing height, as shown above. As long as the operator operates the adjustment 79A to adjust the amount of protrusion of the grounding body 72, the mowing height of the side cutting edge 14 based on the grounding position of the grounding body 72 and the ground can be changed to achieve the adjustment of the mowing height.

[Center mowing height adjustment mechanism]

As shown in FIGS. 10 and 11, an auxiliary plate 81 in a longitudinal posture is fixed to the flange portion of the front wheel transmission case 16, and the auxiliary plate 81 is supported with an engaging plate 82, and the engaging plate 82 is formed to support The shaft core Q is a circular arc surface at the center, and a plurality of engaging holes 82A are bored in the arc surface. In the front bracket 20, a guide bush 83 having a front-rear posture is fixedly disposed at a position facing the engaging hole 82A of the arcuate surface of the engaging plate 82, and the guide bush 83 is supported by the guide bush 83. A retractable latch-like locking member 84 is extended. The lock spring 85 that is biased toward the engaging hole 82A to protrude is provided inside the guide bush 83. The lock member 84 is coupled to the wire to be able to move the lock member 84 away from the lock member 84. One end of the wire 86 is unlocked by the locking operation of the hole 82A.

In this configuration, the engagement plate 82 in which the plurality of engagement holes 82A are formed, and the lock member 84 (an example of the engagement portion) that can be engaged with the engagement hole 82A (an example of the engagement portion) of the engagement plate 82 are configured. There is a switching operation portion F that can freely switch the swinging posture of the front wheel transmission case 16 (an example of the supporting body) so that the swinging posture of the front wheel transmission case 16 is a fixed fixed state and a released state in which the free swing is allowed.

In the vicinity of the grip 7G on the left side of the manipulation handle 7, a lock release lever 88 that is pivoted up and down about the shaft body 89 and whose operation mode is pressed from above to the lower side is supported, and the lock release lever 88 is connected. There is a other end portion of the lock release wire 86. The lock release lever 88 and the lock release wire 86 that can transmit the operation force of the lock release lever 88 to the lock member 84 constitute an operation to perform the operation of the lock member 84 to be separated from the engagement hole 82A of the engaging plate 82. unit. The lock release wire 86 has a structure in which the inner wire can be housed inside the outer wire, and one end of the inner wire is coupled to the lock release lever 88, and the other end of the inner wire is coupled to the lock member 84.

As described above, the locking member 84 including the engaging plate 82 and the plurality of engaging holes 82A that can be detached from the engaging plate 82, the lock spring 85, the lock release wire 86, and the lock release lever 88 constitute a center mowing height adjustment. machine Structure.

The front wheel transmission case 16 is supported so as to be swingable about the support shaft Q, and the locking hole 82A of the engaging plate 82 is locked with the locking member 84, so that the swinging posture of the front wheel transmission case 16 can be maintained. . Further, in the unlocked state in which the lock member 84 is withdrawn from the engagement hole 82A of the engagement plate 82, the weight of the front wheel transmission case 16 allows the front end side thereof to move downward. Further, an auxiliary spring that pushes the front end side of the front wheel transmission case 16 downward may be provided, so that the front end side can be surely moved downward.

According to this configuration, when the operator releases the lock release lever 88 downward, the lock release state of the lock member 84 from the engagement hole 82A of the engagement plate 82 can be set, and in this state, the operator only needs to When the steering handle 7 is operated in the downward pressing direction, the front portion of the movable body A can be lifted by the grounding position of the rear wheel 2 as a fulcrum, and the front wheel transmission case 16 is swung in the direction in which the front end side is lowered. On the other hand, in the unlocked state, if the operator operates the steering handle 7 in the upward direction, the front portion of the movable body A can be depressed by the grounding position of the rear wheel 2 as a fulcrum, and the front wheel transmission case 16 is directed to the front end side thereof. Swing in the direction of the rise. In other words, the lowering or lifting of the operating handle 7 allows the height of the center blade 12 to be arbitrarily set. In this setting state, the locking member 84 can be utilized by releasing the pressing operation of the unlocking lever 88. The spring force of the lock spring 85 is engaged with the engagement hole 82A, and the height of the center blade 12 is maintained to maintain the grass height.

[The role and effect of the embodiment]

When mowing the grass with the horizontal posture and the grass with the slope in the inclined posture, the front wheel 1 and the rear wheel 2 of the mobile body A of the lawn mower are grounded on the road surface, and the side casing is placed. 13 is disposed above the slope surface, and the side casing 13 is set to be swingable about the swing shaft core P. In this state, the grounding of the bowl-shaped grounding body 72 causes the side casing 13 to reach a posture parallel to the wavefront. Then, the mowing clutch operating lever 50 is used to input the mowing clutch mechanism, and the running clutch mechanism 33 is used to input the operation of the running clutch mechanism 27, whereby the road cutting device B can be used along the road surface. At the same time, the bowl-shaped grounding body 72 is in contact with the slope surface in a state of driving rotation, so that it can be rotated with a low resistance to perform smooth movement, and the cutting device can be used as a slope surface. C performs the cutting of the grass on the slope along the shape of the slope.

When the mowing height adjustment of the road surface cutting device B is performed, the locking member 84 can be released from the engaging hole 82A of the engaging plate 82 of the switching operation portion F by pressing the lock release lever 88 with a finger or the like. locking. In the unlocked state, the center blade 12 can be set to the target mowing height by the adjustment of the amount of depression under the steering handle 7 or the adjustment of the amount of lift, and the locking member is released based on the operation of the lock release lever 88. The 84 is engaged with the engaging hole 82A near the height set by the elastic force of the lock spring 85, so that the front wheel transmission case 16 is locked to thereby realize the mowing height adjustment.

When the mowing height adjustment of the slope cutting device C is performed, the operator As long as the adjustment operation of the rotary operation arm 79 is performed, the rotation of the shift shaft 61 can be performed to change the relative distance between the side cutting edge 14 and the grounding body 72, thereby realizing the adjustment of the mowing height.

[Other Embodiments]

The present invention may be configured as described below in addition to the above-described embodiments.

(a) The switching operation portion F is composed of a plurality of pins included in the arcuate surface of the engaging plate shown in the embodiment, and an engaged member having a hole portion to be engaged with the plurality of pins. Even if the switching operation portion F has the above configuration, the mowing height can be adjusted by changing the swing posture of the front wheel transmission case 16 by the engagement of the pin and the hole portion, and the changed state can be firmly maintained. When the configuration is as described above, the operation mode may be set such that the engaged member is separated from the pin by an operation wire or the like to be an operation unit.

(b) The center mowing height adjusting mechanism is formed with a plurality of irregularities on the arcuate surface of the outer periphery of the engaging plate 82, and includes a locking member 84 having a plurality of concave and convex surfaces that are engageable with the plurality of irregularities. Further, a lock spring 85 that can push the lock member 84 in the direction of the engagement plate 82 is provided, and an operation wire or the like that allows the lock member 84 to move away from the engagement plate 82 against the spring force of the lock spring 85 is provided. The center mowing height adjusting mechanism configured as described above is capable of setting the swing of the front wheel transmission case 16 at a smaller angle than the configuration in which the single locking member 84 is engaged with the plurality of engaging holes 82A as described in the embodiment. Posture, which enables subtle settings for mowing height adjustment.

(c) The operating unit is a link mechanism constructed of a rod. Even if the operation unit has the above configuration, the switching operation of the switching operation portion F can be performed from the portion where the handle 7 is manipulated.

(d) The road surface cutting device B is configured to adjust the amount of protrusion of the grounding body 72 downward by the operation of the shift shaft 61. In this way, the utilization of the common parts can be achieved, and the mowing height adjustment of the plurality of blades can be performed in the same operation mode.

(e) The slope cutting device C is configured to include the plurality of side blades 14, and one of the plurality of side blades 14 is provided with a grounding body 72 to execute the grounding body 72. The position is adjusted to form a mowing height adjustment mechanism. As described above, even if the slope cutting device C includes the plurality of side blades 14, the grass height adjustment can be performed by adjusting the amount of protrusion of the one grounding body 72 downward.

(f) As shown in Fig. 12, the upper end of the shift shaft 61 is provided to protrude upward from the second side bevel gear 63B. The shifting device 78 is provided with a shifting device 78 that is an annular groove formed by the engaging member being engaged with the outer periphery of the upper end of the shifting shaft 61, in order to move the shifting device 78 along The side drive shaft core Y moves to form an adjustment portion by screwing the internal thread portion of the screw unit 77A of the operation shaft 77 to the screw unit 78. Even in the above configuration, the operator can move the shifting device 78 in either of the upper and lower directions by grasping the adjustment knob 79A to rotate the operation shaft 77. This operation causes the shifting shaft 61 to move up and down, and the grounding is changed. The relative distance between the body 72 and the side cutting edge 14 in the upper and lower directions enables the adjustment of the mowing height to be achieved.

In particular, in the other embodiment (f), the second side bevel gear 63B and the side drive shaft 62 may be integrally formed into a tubular shape, and the inner surface of the cylindrical body may be spline-shifted. When the configuration of the shaft 61 is the above configuration, the size of the extension side drive shaft 62 can also be increased.

[Industrial availability]

The present invention is capable of utilizing in a lawn mower.

1, 2‧‧‧ wheels (front and rear wheels)

4‧‧‧The original part (engine)

7‧‧‧Handle (manipulation handle)

12‧‧‧ cutting edge (central blade)

13‧‧‧Machine case (side case)

14‧‧‧ cutting edge (side blade)

16‧‧‧Support body and gearbox (front wheel gearbox)

41A‧‧‧Chassis (lower gearbox)

61‧‧‧Shift shaft

62‧‧‧Drive shaft (side drive shaft)

72‧‧‧ Grounding body

77‧‧‧Operating shaft

77A‧‧‧ Screw Department

78‧‧‧ engaging members (shifting device)

82‧‧‧Plywood

82A‧‧‧Cabinet and Snap Hole

84‧‧‧Locking body and locking member

85‧‧‧Lock spring

86‧‧‧Operating wire (locking wire)

88‧‧‧Lock release lever

A‧‧‧body (mobile body)

Dc‧‧‧Transmission mechanism (mower drive mechanism)

F‧‧‧Transition Operation Department

P‧‧‧Swing core

Q‧‧‧Support core

X‧‧‧ drive shaft core (central drive shaft core)

Y‧‧‧ drive shaft core (side drive shaft core)

Figure 1 is a full side view of the lawn mower.

Figure 2 is a general plan view of the lawn mower.

Figure 3 is a side view of the drive system of the lawn mower.

Fig. 4 is a plan view showing a cutting device for a road surface and a cutting device for a slope surface.

Fig. 5 is a cross-sectional view showing a transmission structure of a road surface cutting device and a slope cutting device.

Fig. 6 is a cross-sectional view showing the road surface cutting device and the slope surface cutting device in an operation state.

Fig. 7 is a cross-sectional view showing the configuration of a side mowing height adjusting mechanism.

Figure 8 is a cross-sectional view of the shifting shaft and the shifting device and the operating shaft.

Fig. 9 is an exploded perspective view showing the connection structure of the grounding body.

Fig. 10 is a side view showing the configuration of a center mowing height adjusting mechanism.

Fig. 11 is a cross-sectional view showing a switching operation portion of the center mowing height adjusting mechanism.

Fig. 12 is a cross-sectional view showing the configuration of a side mowing height adjusting mechanism of another embodiment (f).

1‧‧‧ Wheels (front wheel)

7‧‧‧Handle (manipulation handle)

7G‧‧‧ grip

10‧‧‧ body frame

11‧‧‧ center housing

12‧‧‧ cutting edge (central blade)

16‧‧‧Support body and gearbox (front wheel gearbox)

18‧‧‧ input shaft

19‧‧‧Front wheel drive shaft

20‧‧‧ front bracket

33‧‧‧Driving clutch handle

34‧‧‧Travel clutch wire

81‧‧‧Auxiliary board

82‧‧‧Plywood

82A‧‧‧Cabinet and Snap Hole

83‧‧‧Guide

84‧‧‧Locking body and locking member

85‧‧‧Lock spring

86‧‧‧Operating wire (locking wire)

88‧‧‧Lock release lever

89‧‧‧Axis

F‧‧‧Transition Operation Department

Q‧‧‧Support core

Claims (8)

A lawn mower includes a cutting blade for cutting a blade that rotates around a driving shaft core in a longitudinal posture, and a front wheel is provided at a front portion of the body, and has a handle extending rearward from the body Further, the support body for supporting the front wheel is supported by the support body in a lateral posture around the support shaft core, and the height of the cutting blade is adjusted according to the setting of the swing posture of the support body. The adjustment mechanism is characterized in that the adjustment mechanism is configured to include a switching operation unit that can freely convert the posture of the support body into a fixed state in which the posture of the support body is fixed, and a release in which the posture of the support body is allowed to swing freely. In a state in which the support body is set to the released state by the switching operation unit, the front wheel is freely displaced downward or upward according to the setting of the lifting height of the front portion of the body, and the displacement allows the support body to be accommodated. swing. The lawn mower according to the first aspect of the invention, wherein the conversion operation unit includes a plurality of engagement portions corresponding to a plurality of swinging postures of the support body, and one of the engagement portions that are engaged with the plurality of the plurality of engagement portions The engagement portion holds the lock body in the swinging posture of the support body, and the conversion operation portion further includes an operation unit that performs switching between the engagement portion and the lock body. The lawn mower according to the second aspect of the invention, wherein the plurality of engagement portions are configured to include an engagement plate having a plurality of arc-shaped regions centered on the support shaft core Engagement hole, the locking body is configured by a locking member that can be detached from the engaging hole The switching operation portion has a lock spring that can obtain a spring force to engage the lock member with the engagement hole, and the operation unit has an operation wire that can bias the lock member from the engagement hole, and the operation wire is transmitted through the operation wire. A lock release lever that urges the force in a direction in which the lock member can be separated from the engagement hole is provided in the handle. The lawn mower according to any one of claims 1 to 3, wherein the body has a motive portion, and the support body is provided with a transmission mechanism for driving the driving force from the motive portion. It is composed of a transmission case that is transmitted to the above front wheel. A lawn mower is a lawn mower equipped with a cutting blade at a lower end side of a drive shaft that rotates around a drive shaft core in a longitudinal position, and a grounding body is disposed on a lower end side of the drive shaft. a shifting shaft that is movable integrally with the drive shaft along a drive shaft of the drive shaft in a state of being embedded in the drive shaft, and the grounding body is provided at a lower end of the shift shaft, and An adjustment unit that adjusts the amount of protrusion of the shift shaft downward is provided. The lawn mower according to claim 5, wherein the drive shaft is rotatably supported by the casing, and is formed in a tubular shape having a hole through which the displacement shaft is inserted, and the hole portion is formed in the hole portion. Between the inner circumference and the outer periphery of the shift shaft, a transmission means for allowing the shift shaft to move up and down with respect to the drive shaft and integrally rotating the drive shaft and the shift shaft is formed. The lawn mower described in claim 6 of the patent application, wherein The adjustment unit includes: an engagement member that engages with the shift shaft in a state in which the shift shaft is allowed to rotate; an operation shaft that is rotatably provided in a posture parallel to the drive shaft core; and the operation shaft a screw portion that moves the engaging member along the drive shaft core during the rotating operation. The lawn mower according to claim 6 or 7, wherein the body is provided with a wheel and a motive portion that are in contact with the ground, and a swing shaft core that supports the front and rear postures is supported at a side portion of the body. The base end portion of the casing that is swingable at the center is supported by the casing, and the drive shaft is provided with a transmission mechanism for transmitting a driving force from the motive portion.