JP2006238796A - Walking type lawn mower - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a walking type lawn mower which can efficiently prevent that mowed lawns are scattered, when a grass-collecting box 23 is carelessly switched into a releasing posture in a state that a mower device 15 is driven. <P>SOLUTION: One end of a connection link 103 is slidably and non-insertably connected to a clutch operation board 106 integrally turned with a PTO clutch lever 12 through a connection block 109. The other end of the connection link 103 is turnably pivoted to a fixed link 83 attached to the rotation support shaft 71 of the grass-collecting box 23. The connection block 109 permits the sliding of the connection link 103, when the PTO clutch lever 12 is switched off, and holds the connection link 103 in a non-slidable state, when the PTO clutch lever 12 is switched on. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a traveling lawn mower provided with a mower device for mowing turf grass planted on the ground.

  Generally, a traveling lawn mower includes a mower device for mowing mounted on a traveling machine body, a discharge duct through which the mowing lawn cut by the mower device is conveyed, and a grass collection box that communicates with the exhaust duct. ing.

  An example of this type of traveling lawn mower is disclosed in Patent Document 1. In the traveling lawn mower disclosed in Patent Document 1, the grass collection box disposed at the rear of the traveling machine body is driven by a hydraulic cylinder so that the opening is directed to the discharge duct and the grass collection posture for receiving the cut grass and the opening on the ground. It is configured to be able to rotate up and down around a horizontal rotation support shaft so as to switch to a discharge posture in which the cut grass is discharged.

  The discharge duct is formed in a U shape with a downward cross section. A rotating plate (deflecting plate) is provided at the lower rear end in the discharge duct. The rotating plate is configured to be able to turn up and down (up and down) around the rear end so as to open and close the outlet (rear opening) of the discharge duct in conjunction with the posture changing rotation of the grass collection box. .

  In this configuration, when the grass collection box is in the grass collection posture, the rotation plate rotates downward, and the discharge duct communicates with the grass collection box. The cut grass cut by the mower device is collected in the grass collection box via the discharge duct.

On the other hand, when the grass collection box is in the discharge posture, the rotating plate is flipped up and pivoted to cut off the communication between the discharge duct and the grass collection box, and a large discharge opening is made at the lower part of the discharge duct. Therefore, for example, even if the grass collecting box is switched to the discharge posture while the mower device is driven, the mowing lawn is not scattered backward from the discharge duct outlet and is directed from the discharge duct outlet to the ground. Discharged.
JP 2004-113135 A (see FIGS. 5 and 8)

  However, according to the configuration of Patent Document 1, with the mower device being driven as described above, the mowing lawn is discharged from the discharge port of the discharge duct toward the ground even if the rotating plate is flipped up and rotated. Therefore, the mowing lawn is still scattered around. Also, if an unexpected situation occurs where the rotating plate becomes unable to rotate due to clogging of the mowing lawn, etc., if the grass collecting box is inadvertently switched to the discharge position while the mower device is driven, the mowing lawn will It will be scattered backward from the outlet of the discharge duct. For this reason, a traveling lawn mower has been required to adopt a mechanism that more effectively prevents the mowing lawn from being scattered.

  Therefore, the present invention has a technical problem to meet such a demand.

  In order to solve this technical problem, the invention of claim 1 includes a mower device mounted on a traveling machine body so as to be movable up and down, and a grass collection box communicating with a discharge duct extending from the mower apparatus. A part of the rotational power from the power source mounted on the mower device is transmitted to the mower device, and the grass collecting box receives the mowing grass cut by the mower device and the collected grass posture. While the posture can be changed to the release posture for releasing the turf, the PTO clutch that interrupts the transmission of power to the mower device is turned on and off by the turning on and off operation of the PTO operation means provided on the traveling machine body. A traveling lawn mower configured as described above, wherein the traveling machine body is allowed to change the posture of the grass collection box when the PTO operation means is in a cut state, and the PTO operation The grass collection box when stage of engaged condition is that has a working inhibition means for maintaining the grass collecting posture.

  According to a second aspect of the present invention, in the traveling type lawn mower according to the first aspect, the operation restricting means includes a fixed link fixed to a rotation support shaft that supports the grass collection box so that the posture of the grass collection box can be changed and rotated. A connecting link that connects the PTO operating means, and one end of the connecting link is slidably connected to the other of the PTO operating means and the fixed link via a connecting body and cannot be removed; The other end of the connection link is pivotally attached, and the connecting body allows the connection link to slide when the PTO operation means is in a cut state, and when the PTO operation means is in an on state. The connection link is configured to be non-slidable.

  According to a third aspect of the present invention, in the traveling type lawn mower according to the first aspect, the operation restricting means is provided in an oil path between a hydraulic cylinder that drives the grass collection box and a hydraulic pump that supplies pressure oil to the hydraulic cylinder. A switching valve disposed and valve control means for controlling the operation of the switching valve, wherein the valve control means is capable of extending and retracting the hydraulic cylinder when the PTO operating means is in the off state, and the PTO operating means The switching valve is controlled so that the hydraulic cylinder is maintained in a shortened state when is in the on state.

  According to the present invention, when the PTO operation means is in the cut state, the grass collection box can be changed between the grass collection posture and the discharge posture, but when the PTO operation means is in the on state, the grass collection box can be changed. The box is maintained in the grass collection posture without changing the posture to the discharge posture due to the restriction of the operation restricting means.

  As a result, if the mower device is driven by entering the PTO operation means and the mower device is driven, the mower device cannot be changed to the discharge posture due to the restriction of the operation restricting means. In this state, the cut grass is transported from the mower device through the discharge duct into the grass collection box. Therefore, it is possible to reliably prevent the mowing lawn from being scattered around the traveling machine body.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Embodiments of the invention will be described below with reference to the drawings (FIGS. 1 to 13). 1 is an overall side view of a traveling lawn mower, FIG. 2 is an overall plan view, FIG. 3 is a plan view showing a power transmission system, FIG. 4 is a plan sectional view showing the relationship between a mower device and a discharge duct, and FIG. 2 is a cross-sectional side view taken along the line V-V in FIG. 2, FIG. 6 is a plan view showing a connection structure between the fuselage frame and the grass collection box, and FIG. FIG. 8 is a schematic side view showing the relationship between the PTO clutch lever and the PTO clutch, FIG. 9 is a first explanatory diagram of a mode in which the grass collection box is rotated to be switched to the discharge posture, and FIG. 10 is a grass collection box. FIG. 11 is a third explanatory diagram of a mode in which the grass collection box is switched and rotated to the discharge posture, and FIG. 12 is a diagram of the mode in which the grass collection box is switched to the discharge posture. FIG. 13 is a hydraulic circuit and a control circuit in another example of the operation restricting means. It is a functional block diagram of a roller.

  First, an outline of a traveling lawn mower will be described mainly with reference to FIGS. 1 and 2. As shown in FIGS. 1 and 2, in the traveling lawn mower according to the embodiment, the traveling machine body 1 includes a body frame 2 having a gate shape in plan view. The body frame 2 is supported by front and rear four wheels 3, 3, 4, and 4 disposed on the left and right sides of the body frame 2. The left and right rear wheels 4, 4 of the embodiment are mounted on the outside of the lower ends of a pair of portal brackets 14, 14 fixed to the left and right outer surfaces of the body frame 2.

  An engine 6 as a power source and a steering column portion 7 having a steering round handle 7a are mounted on the front cowl 5 that covers the front upper surface of the traveling machine body 1. In the rear cowl 8 covering the rear upper surface of the traveling machine body 1, there is a transmission case 9 such as an HST type (hydrostatic continuously variable transmission mechanism) that appropriately changes the output from the engine 6 and transmits it to the left and right rear wheels 4, 4. Is arranged (see FIG. 3).

  A driver seat 10 is provided on the rear cowl 8. When the operator sitting on the driver's seat 10 turns the steering round handle 7a, the steering angles (steering angles) of the left and right front wheels 3 and 3 change according to the amount of operation (the amount of rotation). It is configured.

  As shown in FIG. 2, on the left side of the driver's seat 10, a mower elevating lever 11 for elevating a mower device 15 described later is provided so as to be able to rotate back and forth. On the right side of the driver's seat 10, a posture switching lever 13 as an operation means for switching a posture of a grass collection box 23, which will be described later, or a PTO clutch lever 12 that performs power transmission from the PTO shaft 30 to a mower device 15 to be described later. Is provided so as to be pivotable back and forth.

  Note that a shift pedal for appropriately adjusting the vehicle speed of the traveling machine body 1 and a brake pedal for braking the traveling machine body 1 are provided upright on the back surface (rear surface) side of the steering column unit 7.

  A mower device 15 is mounted on the lower surface of the body frame 2 between the left and right front wheels 3 and 3 and the left and right rear wheels 4 and 4 via a pair of front and rear connecting rods 16 and 17. . The mower device 15 is provided with a pair of left and right rotary cutting blades 19 and 19 that can rotate horizontally in a mower case 18 having a downward opening hook shape (see FIG. 3).

  Further, four gauge wheels 20 that adjust the height of the mower device 15 when lowered are attached to the front and rear of the left and right sides of the mower case 18. The more case 18 is provided with a duct portion 21 extending rearward. The duct portion 21 communicates with a grass collection box 23 disposed at the rear portion of the traveling aircraft body 1 through a discharge duct 22 disposed between the left and right rear wheels 4 and 4 on the lower surface of the vehicle body frame 2. .

  Next, a power transmission system of the traveling lawn mower will be described with reference to FIG. The traveling lawn mower according to the embodiment employs a two-wheel drive system in which a part of the rotational power of the engine 5 is distributed to the left and right rear wheels 4 and 4.

  That is, part of the rotational power of the engine 6 is from the rear end portion of the output shaft 24 projecting outward in the front-rear direction to the engine 6, the propulsion shaft 25 having universal joints at both front-rear ends, and the front of the transmission case 9. Is transmitted to the transmission case 9 via the traveling gear box 26 and the endless belt 27. And the left and right longitudinal rear wheel drive provided on the rear side portion of the traveling machine body 1 from a horizontal shaft (not shown) projecting outwardly on the transmission case 9 via an endless chain (not shown). It is transmitted to the shaft 28. As a result, the rear wheels 4 and 4 attached to the left and right ends of the rear wheel drive shaft 28 are rotationally driven.

  On the other hand, the other rotational power of the engine 6 is transmitted from the front end portion of the output shaft 24 to the PTO shaft 30 pivotally supported by the front portion of the body frame 2 through the endless belt 29. Next, from the PTO shaft 30, an intermediate shaft 31 having universal joints at both front and rear ends, a mower gear box 32 disposed on the right side of the machine body frame 2 on the upper surface of the mower case 18, and an endless belt 33. In the mower case 18, power is transmitted to the longitudinal rotary shafts 34 and 34 that are rotatably supported on both sides of the machine body frame 2 in plan view. As a result, the left rotary cutting blade 19 is driven to rotate clockwise in plan view, and the right rotary cutting blade 19 is driven to rotate counterclockwise in plan view.

  Due to the rotation of the left and right rotary cutting blades 19, 19, a conveying wind that flows backward from the mower case 18 toward the grass collection box 23 is formed. The conveying wind smoothly conveys the cut grass cut by the rotary cutting blades 19 to the grass collection box 23.

  Next, a communication structure between the duct portion 21 of the mower case 18 and the grass collection box 23 will be described with reference to FIGS. 4 and 5.

  A duct portion 21 extending rearward from the mower case 18 opens upward and rearward. The upward opening 21a of the duct portion 21 is covered with an upper cover body 35 that is U-shaped in a downward cross section. In the embodiment, the front end portions of the left and right side plates in the upper cover body 35 are connected to the duct portion 21 by a pair of left and right pivot pins 36, 36 so as to be vertically rotatable. The rear end portion of the upper cover body 35 is inserted into the carry-in port (front opening) of the discharge duct 22. A torsion spring 37 is fitted on each pivot pin 36. The upper cover body 35 is urged by the elastic restoring force of each torsion spring 37 in the direction of rotating upward so as to always contact the upper inner surface of the discharge duct 22.

  The discharge duct 22 communicating with the space surrounded by the duct portion 21 and the upper cover body 35 of the mower case 18 includes a main duct body 41 having a U-shaped cross-section that is fixed to the body frame 2, and left and right sides of the main duct body 41. A pair of oscillating side plates 42, 42 disposed on the front inner surface of both side plates, and two front and rear rotating plates 43, 44 that close the downward opening 41 a of the main duct body 41 are provided. The two front and rear rotating plates 43 and 44 are undulated (up and down) by interlocking with each other via a link rod 53 as a link mechanism disposed on the lower surface side of the two rotating plates 43 and 44. It is configured to move.

  Each swing side plate 42 is connected to the main duct body 41 so as to be vertically rotatable by pivotally attaching rear end portions thereof to left and right side plates of the main duct body 41 with pivot pins 45. The front part of each swing side plate 42 (free end near the mower device 15) is linked so that the swing side plate 42 rotates up and down around the pivot pin 45 in conjunction with the up and down movement of the mower device 15. It is connected to the mower case 18 through 46 (see FIGS. 1 and 5).

  A horizontally extending front shaft 47 is mounted between the central lower portions of the left and right swing side plates 42, 42. A support pin 48 that protrudes inward in the left-right direction is fixed to a portion of the swing side plate 42 in front of the front shaft 47. A support bar 49 having a circular cross section and a thin shaft shape is mounted on the left and right oscillating side plates 42 and 42 at a position behind the front pivot shaft 47.

  The front rotation plate 43 that closes the front half of the downward opening 41a is fitted to the front pivot 47 so that the cylindrical member 50 provided on the rear surface of the lower surface can be rotated. It is attached so as to be able to turn up and down (up and down) around the front axis 47. When the front rotation plate 43 is rotated downward so as to block the front half of the downward opening 41a, the front portion is supported by contacting the pair of left and right support pins 48, 48. In other words, the downward rotation of the front rotation plate 43 is restricted to a position (see FIGS. 4 and 5) where the front portion of the front rotation plate 43 abuts both the support pins 48, 48.

  The rear rotating plate 44 is a rectangular thin plate having an area enough to fit in the rear half of the downward opening 41 a and the outlet (rear opening) of the discharge duct 22. The rear rotating plate 44 is pivotally fitted to a rear shaft 51 mounted between the rear portions of the left and right portal brackets 14 and 14 so as to be rotated left and right. It is attached to both gate type brackets 14 and 14 so as to be able to turn up and down (up and down) around the rear axis 51.

  When the rear rotating plate 44 is rotated downward so as to close the latter half of the downward opening 41 a, the front portion is supported by being in contact with the horizontally long support bar 49 via the link rod 53. Due to the presence of the support bar 49, the rear rotation plate 44 does not rotate downward until the position shown in FIGS. 5 and 9 to 11 is exceeded.

  The front and rear lengths of the front and rear rotating plates 43 and 44 are set to such a length that the front end (front end) does not interfere with the ceiling surface of the discharge duct 22 during the flip-up rotation.

  A link rod 53 as a link mechanism disposed on the lower surface side of both the front and rear rotating plates 43 and 44 is a substantially I-shaped bar shape in which a laterally cylindrical boss portion 54 is integrally formed at both longitudinal ends thereof. . In the embodiment, the connecting pin 56 is one bracket in a state where the boss portion 54 of the link rod 53 is interposed between a pair of left and right bracket pieces 55, 55 fixed to the rear lower portion of each rotating plate 43 (44). It is inserted and fixed so that it can be inserted and removed from the piece 55 through the boss portion 54 to the other bracket piece 55.

  In this case, a long gap portion 57 is formed in the rear end portion of the front rotating plate 43 at a position overlapping with one end portion (front end portion) of the link rod 53 in plan view. Due to the presence of the gap portion 57, even if a longitudinally extending link rod 53 is arranged on the lower surface side of both the rotating plates 43, 44 so as to straddle both the 43, 44, the interlocking of both the rotating plates 43, 44 is performed. At this time, interference between the rear end portion of the front rotation plate 43 and the link rod 53 is avoided.

  A hole formed in both bracket pieces 55, 55 of the front rotating plate 43 and through which the connecting pin 56 passes is a long and narrow elongated hole for smoothly rotating the rotating plates 43, 44 up and down. It has become. Accordingly, the front rotation plate 43 is flipped up and slightly delayed after the rear rotation plate 44 is flipped up, and the rear rotation plate 44 has its tip (front end) at the front rotation plate 43. It can be flipped up and turned smoothly without being caught on the rear end. At the front end of the link rod 53, a closing plate 58 is provided for closing the gap 57 when the front rotating plate is rotated downward.

  A transmission arm 59 is fixed to one end portion of the rear pivot 51 that protrudes outside the portal bracket 14 so as to extend in a direction intersecting the rear pivot 51. The distal end portion of the transmission arm 59 is connected to the other end portion of a relay rod 97 described later.

  Next, a connection structure between the body frame 2 and the grass collection box 23 will be described with reference mainly to FIGS.

  The grass collection box 23 has a substantially box shape with an open front surface, and rotates around a pivotal support shaft 71 so as to switch between a grass collection posture and a discharge posture by driving a hydraulic cylinder 101 (details will be described later) as an actuator. It is configured to rotate up and down. The grass collection box 23 includes a frame frame 61 that constitutes the framework, a bottom plate 62 that forms the bottom surface of the grass collection box 23, and a net or cloth bag 63 that covers the frame frame 61 and the bottom plate 62. Yes. A front end portion of the bottom plate 62 is pivotally supported with respect to the frame frame 61 by a horizontally long horizontal shaft 64 so as to be rotatable around the horizontal shaft 64. A lid cover body 65 is detachably provided on the upper surface of the grass collection box 23 to prevent dust passing through the mesh of the bag body 63 from turning around to the traveling machine body 1 side.

  A pair of left and right plate plates 66 are fixed to a portion of the upper portion of the frame frame 61 near the front opening. Both plate plates 66 and 66 are detachably connected to a support frame 72 mounted on the rear end portion of the machine body frame 2 by a horizontal cylindrical rotation support shaft 71. Engagement fittings 73, 73 that rotate integrally with the rotation support shaft 71 are arranged on both sides of the support shaft 72 with respect to the rotation support shaft 71. Both the engagement fittings 73 and 73 are configured to be engaged with and disengaged from the rear beam frame 114 located behind the rotation support shaft 71 in the frame frame 61 by rotating around the rotation support shaft 71. ing.

  When both the engagement fittings 73 and 73 are rotated upward by the rotation of the rotation support shaft 71 about its own axis, the both engagement fittings 73 and 73 are engaged with the rear beam frame 114 from below and lifted up. As a result, the grass collection box 23 is rotated upward about the rotation support shaft 71 to be in a discharge posture in which the front opening is directed to the ground and the cut grass is discharged (see the two-dot chain line state in FIG. 1 and FIG. 12). ).

  On the contrary, when both the engagement fittings 73, 73 rotate downward, the engagement between the engagement fittings 73, 73 and the rear beam frame 114 is released, and the grass collection box 23 is free with respect to the rotation support shaft 71. It will be able to rotate. Accordingly, the grass collection box 23 rotates downward about the rotation support shaft 71 by its own weight, and receives the grass cut by the mower device 15 with the front opening facing the exit of the discharge duct 22. (Refer to the solid line state in FIG. 1, see FIGS. 5 and 9.)

  The support frame 72 includes a horizontally long pipe member 74 into which the rotation support shaft 71 is rotatably inserted, side frames 75 and 75 disposed on the left and right sides of the pipe member 74, and the both side frames 75, And a cross beam member 76 fixed between the front portions of 75. Each side frame 75 is fixed to one side surface of the insertion tube portion 77 having a horizontally long cylindrical shape, a standing portion 78 projecting upward at the rear end of the insertion tube portion 77, and the insertion tube portion 77 and the standing portion 78. It consists of a side plate 79. In the embodiment, each insertion pipe portion 77 of the support frame 72 is fitted and attached to the left and right rear ends of the body frame 2 from the rear.

  The left and right end portions of the rotation support shaft 71 are rotatably inserted into shaft holes 66 a formed in the plate plates 66 of the frame frame 61. A cylindrical member 80 fixed to the above-described engagement fitting 73 is fitted between one end of the rotation support shaft 71 between the pipe member 74 and the plate plate 66.

  In the embodiment, the headed first connecting shaft 81 is inserted into the inner diameter portion of the rotation support shaft 71 that passes through the shaft hole 66 a of one plate plate 66. Then, a hole 81 a formed through the tip of the first connecting shaft 81, a hole 71 a formed through one end of the rotation support shaft 71, and a hole 80 a formed through the cylindrical member 80 are matched. In this state, the first locking pin 82 is detachably inserted into the holes 71a, 80a, 81a. As a result, the first connection shaft 81, the rotation support shaft 71, and the cylindrical member 80 are connected together so that they rotate together and the rotation support shaft 71 cannot be removed from the one plate plate 66. Has been.

  At the other end of the rotation support shaft 71, the aforementioned engagement fitting 73 and the pair of fixed links 83, 84 are fixed between the pipe member 74 and the plate plate 66 (the fixed link is at least 1). You only have to) Between the second fixed link 84 and the pipe member 74 in the rotation support shaft 71, a substantially diamond-shaped rotation link 85 is rotatably fitted.

  In the embodiment, a cylindrical member 87 fixed to the lock arm 86 is disposed at a location outside the other plate plate 66, and the pivot support that penetrates the cylindrical member 87 and the shaft hole 66 a of the other plate plate 66. A long shaft portion 89 of a second connecting shaft 88 formed in a substantially J shape is inserted into the inner diameter portion of the shaft 71. Then, a hole formed in the distal end of the long shaft portion 89 of the second connecting shaft 88 in a hole 71 b formed in a position between the first fixed link 83 and the engagement fitting 73 in the rotation support shaft 71. A second locking pin 91 is detachably inserted through 89b. Thus, the second connecting shaft 88 and the rotating support shaft 71 are connected so that the rotating support shaft 71 cannot be removed from the other plate plate 66.

  A fitting hole 86 a for fitting the short shaft portion 90 of the second connecting shaft 88 is formed in a substantially central portion of the lock arm 86. In the embodiment, the second connecting shaft 88 and the rotation support shaft 71 are connected by the second locking pin 91, and the short shaft portion 90 of the second connecting shaft 88 is inserted into the fitting hole 86 a of the lock arm 86. Thus, the lock arm 86 is configured to rotate integrally with the rotation support shaft 71.

  An end of the lock arm 86 opposite to the cylindrical member 87 is an engagement link fixed to an end of the horizontal shaft 64 located at the front end of the lower end of the grass collection box 23 via a substantially rod-shaped linkage 100. 92. The engagement link 92 is rotated about the horizontal axis 64 so as to be engaged with and disengaged from a hook-shaped engagement piece 93 (see FIGS. 9 and 10) provided at the lower end of the rear end of the discharge duct 22. It is configured.

  A pair of left and right fixed links 83 and 84 are pivotally attached to a tip end portion of a piston rod 102 protruding from a hydraulic cylinder 101 as an actuator by a horizontally long guide pin 94. A base end portion of the hydraulic cylinder 101 is connected to a bracket 95 provided at a rear end portion of the machine body frame 2 so as to be rotatable by a pin shaft 96 (see FIGS. 5 and 6).

  A hook-like portion 104 formed at one end of a connecting rod 103 (details will be described later) serving as an operation restricting means is fitted into the insertion hole 83a formed in the middle of the first fixed link 83. The other end of the connecting rod 103 is connected to a clutch operation plate 106 fixed to a lever shaft 105 that is the rotation center of the PTO clutch lever 12.

  The rotation link 85 is formed with a substantially arcuate guide groove 85a centering on the rotation support shaft 71 in a side view. In the embodiment, the leading end portion of the guide pin 94 that connects both the fixed links 83 and 84 and the piston rod 102 of the hydraulic cylinder 101 is slidably inserted into the guide groove 85a.

  One end of a substantially elongated relay rod 97 is pivotally attached to the lower end of the pivot link 85 by a pivot pin 98. The other end of the relay rod 97 is pivotally attached to a transmission arm 59 fixed to one end of the rear pivot 51 with a pivot pin 99. Due to the presence of the relay rod 97, the rotation link 85 on the grass collection box 23 side and the transmission arm 59 on the discharge duct 22 side are configured to rotate in opposite directions in conjunction with each other. That is, for example, when the rotation link 85 is rotated clockwise, the transmission arm 59 is configured to rotate counterclockwise.

  The fixed links 83 and 84 and the rotation link 85 on the rotation support shaft 71 side, the transmission arm 59 on the discharge duct 22 side, and the relay rod 97 connecting the rotation link 85 and the transmission arm 59 are patented. This corresponds to the linking means described in the claims.

  Next, with reference to FIGS. 5 and 8, etc., an operation restricting means for permitting or restricting the posture switching rotation of the grass collection box 23 according to the on / off state of the PTO clutch lever 12 will be described.

  A clutch operation plate 106 that integrally rotates about the lever shaft 105 together with the PTO clutch lever 12 is connected to a tension clutch type PTO clutch 107 by a clutch wire 108. In the embodiment, the PTO clutch lever 12 and the clutch operation plate 106 correspond to the PTO operation means described in the claims.

  When the PTO clutch lever 12 is tilted backward to the entry position indicated by the solid line in FIG. 8, the clutch wire 108 is pulled and the PTO clutch 107 presses the endless belt 29 (see FIGS. 3 and 8). Thereby, the endless belt 29 is tensioned and the power from the engine 6 is transmitted to the PTO shaft 30. When the PTO clutch lever 12 is tilted forward to the cutting position indicated by the one-dot chain line in FIG. 8, the clutch wire 108 is loosened and the PTO clutch 107 is separated from the endless belt 29. Thereby, the endless belt 29 is loosened, and the power transmission from the engine 6 to the PTO shaft 30 is interrupted.

  A connecting block 109 as a connecting body is pivotally attached to the lower end portion of the clutch operation plate 106 so as to be rotatable. The connecting block 109 is formed with a sliding hole penetrating in the front-rear direction. In the sliding hole of the connection block 109, the other end portion of the connecting rod 103 as the operation restricting means is slidably inserted along its longitudinal direction. At the other end of the connecting rod 103 in front of the connecting block 109, a retaining pin 110 for retaining is fixed.

  When the grass collection box 23 is in the grass collection posture, when the PTO clutch lever 12 is rotated back and forth around the lever shaft 105 by the rotation stroke θ from the cut position to the entry position, the connecting block 109 is moved relative to the connecting rod 103. , It is configured to slide in the front-rear direction with a sliding stroke L from the foremost position (see the solid line state in FIG. 8) to the last position (see the one-dot chain line state in FIG. 8).

  When the grass collection box 23 is in the grass collection posture and the PTO clutch lever 12 is in the disengaged position, the other end of the connecting rod 103 protrudes forward from the connection block 109 by the sliding stroke L. As a result, when the first fixed link 83 pulls the connecting rod 103 backward when the grass collection box 23 is switched to the discharge posture and rotated, the connecting rod 103 slides backward by the sliding stroke L. Therefore, the connection between the clutch operation plate 106 and the connecting rod 103 does not hinder the rotation of the grass collection box 23 to the release posture. In other words, when the PTO clutch lever 12 is in the disengaged position, the grass collection box 23 can be switched and rotated between the grass collection posture and the discharge posture.

  When the PTO clutch lever 12 is in the engaged position, the stop pin 110 provided at the other end of the connecting rod 103 is located in the vicinity of the connecting block 109. Even if it tries, the stop pin 110 hits the connecting block 109 and the connecting rod 103 cannot slide any further. Thereby, the switching rotation to the discharge | emission attitude | position of the grass collection box 23 is controlled.

  That is, when the PTO clutch lever 12 is in the disengaged position, the posture switching lever 13 can be operated to rotate and change the posture of the grass collection box 23 between the grass collection posture and the discharge posture. When in the entrance position, regardless of the operation of the posture switching lever 13, the grass collection box 23 is maintained in the grass collection posture and does not rotate to the discharge posture.

  With this configuration, even when the posture switching lever 13 is operated so that the grass collecting box 23 is in the discharge posture while the mower device 15 is driven by operating the PTO clutch lever 12, the rear of the connecting rod 103. Therefore, the grass collection box 23 cannot be switched to the discharge posture. Therefore, in a state where the mower device 15 is driven, the cut grass is conveyed from the mower device 15 through the discharge duct 22 into the grass collection box 23, and the cut grass is scattered around the traveling machine body 1. Can be reliably prevented.

  When the grass collection box 23 is in the releasing posture, the stop pin 110 provided at the other end of the connecting rod 103 is positioned in the vicinity of the connecting block 109. Therefore, even if the PTO clutch lever 12 is to be entered and operated, When the stop pin 110 hits the connecting block 109, the clutch operation plate 106 cannot rotate around the lever shaft 105 in the clockwise direction of FIG. As a result, even if an operator tries to enter the grass box 23 inadvertently when the grass collection box 23 is in the releasing posture, the PTO clutch lever 12 cannot be tilted backward to the entrance position. The device 15 is not driven (the left and right rotary cutting blades 19, 19 are not driven to rotate).

  Therefore, when the grass collection box 23 is in the discharge posture, the mower device 15 is driven and the mowing lawn is scattered to the rear from the outlet (rear opening) of the discharge duct without being noticed by the operator. It can be prevented.

  The structure of the coupling body is not limited to the above-described coupling block 109 with sliding holes, but, for example, a pin protruding from the clutch operation plate 106 with respect to a long slot formed in the other end of the connecting rod 103. A configuration in which the shaft is slidable and cannot be removed may be employed.

  FIG. 13 shows another example of the operation restricting means. In this example, pressure oil is supplied to or stopped from the hydraulic cylinder 101 in the oil path between the hydraulic cylinder 101 and a hydraulic pump (not shown) in the HST transmission case 9 or pressurized oil from the hydraulic cylinder 5. A five-port three-position switching type and spool type switching valve 131 is arranged in which three states of discharging can be selected. The switching valve 131 includes a supply-side electromagnetic solenoid 131a and a discharge-side electromagnetic solenoid 131b. The electromagnetic solenoids 131a and 131b are connected to an output interface of a controller 132 as valve control means.

  Although not shown in detail, the controller 132 is not only a central processing unit (CPU) that executes various operations, but also a read-only memory (ROM) for storing control programs, and an arbitrarily readable / writable memory for storing various data ( RAM), an input / output interface for transmitting data by connecting to various input units and output units.

  The input interface of the controller 132 is connected to a PTO clutch lever 12 constituting PTO operation means, and a posture detection sensor 133 such as a rotary encoder or a rotary potentiometer for detecting the current posture of the grass collection box 23. Therefore, the controller 132 operates the hydraulic cylinder 101 by operating the electromagnetic solenoids 131a and 131b of the switching valve 131 according to the detection signals. In addition to the electromagnetic solenoids 131a and 131b, a drive circuit for the PTO clutch 107 and the like can be connected to the output interface.

  Also in the case of the above configuration, as in the above-described embodiment, when the PTO clutch lever 12 is in the disengaged position, the grass collection box 23 is moved to the grass collection posture and the discharge posture by operating the posture switching lever 13. When the PTO clutch lever 12 is in the engaged position, it is possible to control to keep the grass collection box 23 in the grass collection posture regardless of the operation of the posture switching lever 13.

  Further, when the posture detection sensor 133 detects that the grass collection box 23 is in the release posture, the mower device is controlled by maintaining the PTO clutch 107 in the disengaged state regardless of the operation of the PTO clutch lever. 15 driving can be prevented. Therefore, even in this configuration, when the grass collection box 23 is in the discharge posture, the mowing lawn is prevented from being sprinkled backward from the outlet (rear opening) of the discharge duct.

  Next, an aspect in which the front and rear rotary plates 43 and 44 on the discharge duct 22 side and the grass collection box 23 are rotated up and down will be described with reference to FIGS. Here, it is assumed that the PTO clutch lever 12 is tilted forward in advance to the cut position.

  When the posture switching lever 13 is tilted forward, the piston rod 102 of the hydraulic cylinder 101 is extended, and the pair of fixed links 83 and 84 rotate upward about the rotation support shaft 71 in the counterclockwise direction of FIG. As a result, the pair of engagement fittings 73 and 73 and the lock arm 86 are integrally rotated upward in the counterclockwise direction of FIG. 9 together with the rotation support shaft 71 to which the both fixed links 83 and 84 are fixed.

  Then, both the engagement fittings 73 and 73 engage with the rear beam frame 114 constituting the frame frame 61 from below. Since the lock arm 86 lifts the linkage 100 by its upward rotation, the engagement link 92 is disengaged from the engagement piece 93 of the discharge duct 22 (see FIG. 10).

  In the initial stage of operation shown in FIG. 10, the grass collecting box 23 is free with respect to the rotation support shaft 71 until both the engagement fittings 73, 73 are engaged with the rear beam frame 114 constituting the frame frame 61 from below. Since it is in a rotatable state, the grass collection box 23 maintains the grass collection posture.

  Further, the distal end portion of the guide pin 94 pivotally attached to the piston rod 102 slides toward the rear edge in the guide groove hole 85a of the rotation link 85, so that it can freely rotate with respect to the rotation support shaft 71. In this state, the rotation link 85 itself remains stationary without rotating. As a result, the transmission arm 59 and the rear shaft 51 connected to the rotation link 85 via the relay rod 97 and the both front and rear rotation plates 43 and 44 do not rotate. Accordingly, at this stage, only the engagement release operation between the engagement link 92 and the engagement piece 93 is performed.

  Next, the piston rod 102 of the hydraulic cylinder 101 extends until the tip end portion of the guide pin 94 abuts against the rear end edge of the guide groove hole 85a, and the both fittings 73 and 73 rotate so as to lift the rear beam frame 114. When rotating upward around the support shaft 71, the grass collection box 23 is rotated upward around the rotation support shaft 71 by an appropriate angle δ (for example, about 30 ° to 60 °) so that the front opening is inclined forward and downward. Thus, the discharge posture is inclined forward and downward (see the solid line state in FIG. 11). Generally, at this time, the cut grass in the grass collection box 23 starts to slide down to the ground.

  Even in the middle stage of operation shown in FIG. 11, until the leading end of the guide pin 94 comes into contact with the rear end edge of the guide slot 85a, the pivot link 85 is not pivoted and is stationary. The transmission arm 59 and the rear pivot 51 connected to the rotation link 85 via the front and rear rotation plates 43 and 44 are not rotated, and the posture of closing the downward opening 41a of the discharge duct 22 (main duct body 41) is blocked. To maintain.

  Next, the piston rod 102 of the hydraulic cylinder 101 further expands, and both the engagement fittings 73, 73 rotate upward around the rotation support shaft 71, so that the grass collection box 23 moves around the rotation support shaft 71. Rotating upward, it becomes a discharge posture with the front opening facing downward (see FIG. 12). Then, the cut grass in the grass collection box 23 is discharged at a stretch toward the ground.

  In this case, since the front end portion of the guide pin 94 is in contact with the rear end edge of the guide groove hole 85 a, the rotation link 85 is also rotated upward around the rotation support shaft 71 together with both the engagement fittings 73 and 73. Then, the transmission arm 59 and the rear pivot 51 connected to the pivot link 85 via the relay rod 97 pivot around the rear pivot 51 in the clockwise direction of FIG. 12 (the direction opposite to the pivot support shaft 71). The rear turning plate 44 is turned up and turned around the rear axis 51 so as to block the carry-out port of the discharge duct 22. Since the rear rotation plate 44 is connected to the front rotation plate 43 via the link rod 53, the front rotation plate 43 is flipped up around the front axis 47 in conjunction with the flip-up rotation of the rear rotation plate 44. Rotate. Thereby, the downward opening 41a of the discharge duct 22 (main duct body 41) is opened.

  On the other hand, when the posture switching lever 13 is tilted backward, the piston rod 102 of the hydraulic cylinder 101 is shortened, and the pair of fixed links 83 and 84 rotate downward about the rotation shaft 71 counterclockwise in FIG. As a result, the pair of engagement fittings 73 and 73 and the lock arm 86 are integrally rotated downward in the clockwise direction in FIG. 12 together with the rotation support shaft 71 to which both the fixed links 83 and 84 are fixed.

  Then, the engagement between both the fittings 73 and 73 and the rear beam frame 114 is released, and the grass collection box 23 is in a state of being freely rotatable with respect to the rotation support shaft 71. Due to its own weight, it pivots downward about the pivotal support shaft 71 to return to the grass collecting posture. Since the lock arm 86 pushes down the linkage 100 by its downward rotation, the engagement link 92 is kicked into the engagement piece 93 of the discharge duct 22 and the grass collection box 23 is locked so as not to rotate. .

  Further, since the tip end portion of the guide pin 94 pivotally attached to the piston rod 102 slides and abuts to the front end edge of the guide groove hole 85a of the rotation link 85 by the shortening movement of the piston rod 102, both the engagement fittings 73, 73 and the rotation link 85 rotate downward around the rotation support shaft 71. Then, the transmission arm 59 and the rear pivot 51 connected to the pivot link 85 via the relay rod 97 pivot around the rear pivot 51 in the counterclockwise direction (the direction opposite to the pivot support shaft 71) in FIG. Therefore, the rear rotating plate 44 rotates downward about the rear pivot 51 so as to open the outlet of the discharge duct 22, and in conjunction with this, the front rotating plate 43 rotates downward about the front pivot 47. As a result, the downward opening 41a of the discharge duct 22 (main duct body 41) is closed.

  From the above, according to the traveling type lawn mower of the embodiment, the grass box 23 is rotated to change the posture to the discharge posture and the front and rear both rotation plates only by the operator tilting the posture switching lever 13 forward. 43 and 44 are swung up and rotated, so that every time the cut grass is discharged from the grass collection box 23 whose posture has been changed to the release posture, the cut grass collected on the front and rear rotary plates 43 and 44 is moved forward and backward. The rotary plates 43 and 44 can be slid down on the ground by the flip-up rotation.

  In addition, the front and rear lengths of the front and rear rotating plates 43 and 44 are set to such a length that the front end (front end) does not interfere with the ceiling surface of the discharge duct 22 during the flip-up rotation. Both of the plates 43 and 44 can be largely inclined with respect to the ground during the flip-up rotation, and as a result, the cut grass collected on the both front and rear rotation plates 43 and 44 can be smoothly discharged to the ground. it can. Therefore, clogging of the discharge duct 22 due to the accumulation of cut grass can be reliably suppressed.

  Further, the grass collection box 23 is rotated to the discharge posture such that both the front and rear rotation plates 43 and 44 are swung up after the grass box 23 is rotated to change the posture to the discharge posture. By shifting the operation timing of the rear rotating plate 44 from the flip-up rotation, the mowing lawn is released from the grass collecting box 23 first, so the mowing lawn and the grass collecting box 23 that slide down on the rear rotating plate 43 are released. There is no longer any interference (collision) between the discharged cut grass and the vicinity of the exit of the discharge duct 22. As a result, the piles of the cut grass released from the grass collection box 23 are sufficiently far away from the carry-out port of the discharge duct 22 at the highest position, and the cut grass is located near the carry-out port of the discharge duct 22. No pile of piles will be formed.

  Accordingly, a sufficient space can be secured in the vicinity of the outlet of the discharge duct 22 to collect the cut grass on the rear rotating plate 44, and the cut grass on the rear rotating plate 44 can be reliably placed on the ground. Can be released.

  In addition, as a main configuration for rotating the rear rotation plate 44 upward after the posture change rotation of the grass collection box to the discharge posture, the rotation link 85 in which a substantially arcuate guide groove hole 85a is formed. Therefore, the structure is simple, the number of parts is small, and the manufacturing cost can be reduced.

  In addition, both the front and rear rotating plates 43 and 44 constituting the bottom surface of the discharge duct 22 are rotated up and down (up and down) in conjunction with each other via a link rod 53 as a link mechanism arranged across the lower surface side. Therefore, the bottom surface of the discharge duct 22 can be sufficiently blocked by the front and rear rotating plates 43 and 44 during normal cutting operations. Thereby, the leakage of the cut grass from the bottom surface of the discharge duct 22 can be effectively prevented.

  Since not only the rear rotating plate 44 but also the front rotating plate 43 can be flipped up and turned up, the cut grass can be rotated both forward and backward regardless of where the cut grass accumulates on the bottom surface of the discharge duct 22. The plates 43 and 44 can be slid down on the ground by the flip-up rotation of the plates 43 and 44. This eliminates the need for the operator to manually remove the cut grass that has accumulated in the discharge duct 22, thereby reducing the burden on the operator.

  Further, as a link mechanism for swinging up and down both the front and rear rotating plates 43, 44, a substantially I-shaped rod-shaped link rod 53 in which a horizontal cylindrical boss portion 54 is integrally formed at both longitudinal ends. Therefore, the structure is simple and the number of parts is small, which can contribute to the reduction of the manufacturing cost. In addition, since the link rod 53 is disposed across the lower surfaces of both the rotating plates 43 and 44, the link rod 53 is transported by the cutting grass in the state where both the front and rear rotating plates 43 and 44 are rotated downward. It will be located outside the discharge duct 22 to be performed. Thus, the presence of the link rod 53 does not hinder the transport of the cut grass to the grass collection box 23.

  In the embodiment, the rear rotating plate 44 is set to a size that closes the rear surface opening of the discharge duct 22 in a state in which the rear rotating plate 44 is flipped up and rotated around the rear pivot 51, so When the cut grass is discharged from 23, the carry-out port (rear opening) of the discharge duct 22 is closed by the rotation plate 44 after being turned up around the rear axis 51. Thereby, it is possible to reliably prevent the mowing lawn from flowing backward from the grass collection box 23 into the discharge duct 22.

  The present invention is not limited to the above-described embodiment, and can be embodied in various forms. For example, the grass collecting box and the both front and rear rotating plates are not limited to a configuration that rotates via the linkage means by driving the hydraulic cylinder, but may be a configuration that rotates via the linkage means by a biasing means such as a spring. Good. As a PTO operation means, the structure which connected the other end part of the connection rod 103 directly to the PTO clutch lever 12 may be sufficient, and a switch type may be sufficient instead of a lever type. In addition, the configuration of each unit is not limited to the illustrated embodiment, and various modifications can be made without departing from the spirit of the present invention.

1 is an overall side view of a traveling lawn mower. It is a whole top view. It is a top view which shows a power transmission system. It is a plane sectional view showing the relation between a mower device and a discharge duct. FIG. 5 is a side cross-sectional view taken along line VV in FIG. It is a top view which shows the connection structure of a body frame and a grass collection box. It is an isolation | separation perspective view which shows the relationship between a rotation spindle, a support frame, a connection means, and a grass collection box. It is a schematic side view which shows the relationship between a PTO clutch lever and a PTO clutch. It is the 1st explanatory view of the mode which a grass collection box changes and rotates to a discharge posture. It is the 2nd explanatory view of the mode which a grass collection box changes and rotates to a discharge posture. It is a 3rd explanatory view of the mode which a grass collection box changes and rotates to a discharge posture. It is the 4th explanatory view of the mode which a grass collection box changes and rotates to a discharge posture. It is a functional block diagram of a hydraulic circuit and a controller in another example of the operation restricting means.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Traveling machine body 2 Machine body frame 3 Front wheel 4 Rear wheel 12 PTO clutch lever 13 Posture switching lever 15 Mower device 22 Discharge duct 23 Grass collection box 24 Output shaft 29 Endless belt 30 PTO shaft 41 Main duct body 42 Swing side plate 43 Front rotation plate 44 rear pivot plate 47 front pivot shaft 51 rear pivot shaft 53 link rod 71 pivot shaft 72 support frame body 73 engagement fitting 83 first fixed link 84 second fixed link 85 pivot link 85a guide groove hole 86 lock arm 92 engagement Joint link 93 Engagement piece 94 Guide pin 97 Relay rod 100 Joint 101 Hydraulic cylinder 102 Piston rod 103 Connecting rod 105 Lever shaft 106 Clutch operation plate 107 PTO clutch 108 Clutch wire 109 Connection block 131 Switching valve 132 Controller 133 Attitude detection sensor

Claims (3)

A mower device mounted on the traveling machine body so as to be movable up and down, and a grass collection box communicating with a discharge duct extending from the mower apparatus, and a part of rotational power from a power source mounted on the traveling machine body is the mower device. The grass collection box is configured to be able to change the posture between a grass collection posture for receiving the cut grass cut by the mower device and a discharge posture for discharging the collected cut grass. On the other hand, a traveling lawn mower configured such that a PTO clutch that interrupts power transmission to the mower device is turned on and off by an on / off operation of a PTO operation means provided on the traveling machine body,
The traveling machine body allows the posture change movement of the grass collection box when the PTO operation means is in a cut state, and maintains the grass collection box in a grass collection posture when the PTO operation means is in an on state. With regulatory means,
Traveling lawn mower. The operation restricting means is a connection link that connects the PTO operating means and a fixed link fixed to a rotating support shaft that supports the grass collection box so that the posture of the grass collecting box can be changed and rotated, and the PTO operating means and the fixed One of the links is connected to one end of the connection link through a connecting body so as to be slidable and cannot be removed, and the other end of the connection link is pivotally attached to the other.
The coupling body is configured to allow the connection link to slide when the PTO operation means is in a cut state, and to hold the connection link non-slidable when the PTO operation means is in an on state.
The traveling lawn mower according to claim 1. The operation restricting means includes a switching valve disposed in an oil passage between a hydraulic cylinder that drives the grass collection box and a hydraulic pump that supplies pressure oil to the hydraulic cylinder, and valve control means that controls the operation of the switching valve. With
The valve control means controls the switching valve so that the hydraulic cylinder can be expanded and contracted when the PTO operating means is in the off state, and the hydraulic cylinder is maintained in the shortened state when the PTO operating means is in the on state. To
The traveling lawn mower according to claim 1.

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