JP3672513B2 - Work vehicle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
According to the present invention, a pair of left and right lift arms to which a ground working device located below the vehicle body is connected so as to be movable up and down are attached to the vehicle body by a single rotation support shaft so as to be swingable up and down, and the rotation support shaft is rotated. The present invention relates to a work vehicle including a lift cylinder that is operated to swing the pair of left and right lift arms.
[0002]
[Prior art]
The work vehicle constitutes a working machine used for various kinds of work, for example, a lawn mower is configured by connecting lawn mowers so as to be moved up and down by a lift cylinder.
[0003]
[Problems to be solved by the invention]
In the above working machine, for example, when a lawn mower is connected and traveling, the grounding wheel of the lawn mower may fall into the concave portion of the ground and the lawn mower may be suspended. Therefore, a stopper means for setting the lower limit of the lift arm is provided, and even if the weight of the work device is applied to the link mechanism that connects the work device so as to be movable up and down, if the stopper means acts properly, It can be avoided that the link mechanism has a problem such as the connection posture of the link member being reversed and it is difficult to raise and lower the work device.
Further, in this type of work machine, when the stopper means for setting the lift arm lift limit is provided, the lift cylinder can be advantageously operated while avoiding reaching the stroke end when the work device is lifted.
[0004]
It is an object of the present invention to be able to set the lowering and raising limits of the lift arm with a stopper having a simple structure, and further to support a work vehicle that is supported while preventing the member from being distorted even when the work device is suspended. Is to provide.
[0005]
[Means for Solving the Problems]
The configuration, operation, and effect of the invention according to claim 1 are as follows.
[0006]
〔Constitution〕
A pair of left and right lift arms to which a ground work device located below the vehicle body is connected so as to be movable up and down are attached to the vehicle body by a single rotation support shaft so as to be swingable up and down, and the rotation support shaft is operated to rotate the rotation support shaft. In a work vehicle provided with a lift cylinder that swings and operates a pair of left and right lift arms, positioning portions are provided on both end sides of the rotating support shaft so as to be integrally rotatable, and are individually in contact with the pair of left and right positioning portions. The vehicle body includes a pair of ascending stopper portions for setting the ascent limit of the lift arm and a pair of descending stopper portions for contacting the pair of left and right positioning portions separately to set the descending limit of the lift arm.
[0007]
[Action]
When the lift arm is swung to the ascending side, the rotation support shaft rotates together with the lift arm and the positioning portion comes into contact with the ascent stopper portion, the lift arm reaches the ascent limit. When the lift arm is swung to the lower side, the rotation support shaft rotates together with the lift arm, and the positioning part comes into contact with the lowering stopper part, the lift arm reaches the lowering limit. Thereby, when the lifting operation of the working device is performed, the lifting arm is lifted and the lifting cylinder can be lifted while not reaching the stroke end, and even if the working device is in a suspended state, The working device can be suspended and supported while preventing the lift arm from being lowered to prevent the link member from being connected in a reverse posture. Then, the lift stopper and the lower stopper are applied to the same positioning member to stop the lift arm.
[0008]
If the positioning part is provided only at one position of the rotating spindle, even if the positioning part is provided at the central part in the longitudinal direction of the rotating spindle, both lifts will be supported from the point that the support by the lowering stopper part of the rotating spindle acts. The span to the arm is relatively long. On the other hand, since the positioning portions are provided on both ends of the rotating support shaft, both positioning mechanisms are positioned near the left and right lift arms, and both support points from the lower support portion of the rotating support shaft act. When the span to the lift arm is shortened and the work device is suspended, the rotating support shaft is made relatively light due to the support point by the descent stopper and the short span to the lift arm. However, it is possible to suspend and support the working device while preventing distortion from occurring.
[0009]
〔effect〕
Therefore, both the upper limit stop and the lower limit stop of the lift arm are applied to the rotation support shaft, preventing the lift cylinder from reaching the stroke end and reversing the link connection posture to the link mechanism even when the work device is suspended. The work device can be lifted and lowered while preventing troubles such as
[0010]
In addition, both the lowering stopper part and the raising stopper part can be obtained at low cost with a simple structure that acts on the same positioning member. Further, even when the working device is in a suspended state or the rotating support shaft is relatively light, the working support is firmly suspended and supported so that the rotating support shaft is unlikely to be distorted.
[0011]
The structure, operation, and effect of the invention according to claim 2 are as follows.
[0012]
〔Constitution〕
In the configuration of the invention according to claim 1, the vehicle body is located on the vehicle body having a transmission case connecting the clutch housing and the transmission case, and separated from both lateral sides of the vehicle body, and one end side is the clutch housing. And a pair of vehicle body reinforcement frames each having the other end connected to the transmission case, and the vehicle body reinforcement frame includes the ascending stopper portion and the descending stopper portion.
[0013]
[Action]
The vehicle body reinforcement frame is provided with the above-mentioned ascending stopper part and descending stopper part, and firmly acts on the positioning member to firmly set the upper and lower limits of the lift arm, and acts firmly on the lift arm. is there.
[0014]
〔effect〕
Therefore, the upper and lower limits of the lift arm are set, the rotation support shaft is firmly supported to support the work device in a suspended state, the limit of the lift arm is set, the link connection posture is prevented from being reversed, and the work device is suspended. Lowering support is surely performed firmly.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1, a pair of left and right front wheels 6 that can be driven and steered, a pair of left and right rear wheels 8 that can be driven, a driving portion having an engine 1 located at the front end of the vehicle body, and a driving located at the rear portion of the vehicle body A pair of left and right rear lift arms 13 that connect a working device such as a rotary tiller to a transmission case 3 that forms a rear portion of a vehicle body B having a boarding type driving unit having a seat S, and the above-described operation; A power take-off shaft 10 for transmitting the driving force from the engine 1 to the work device is provided to constitute a riding work vehicle, and the lawnmower M is placed between a pair of left and right lifts below the front and rear wheels of the vehicle body B of the work vehicle. The link mechanism L having the arms 20, 20 is connected so as to be movable up and down, and the driving force from the power take-out part 11 of the transmission case 3 is driven by the rotary shaft 27 to the mower deck 1 of the lawn mower M. And transmitted to the input unit 24 located on the upper surface of, and configured to drive the rotary blade located inside the mower deck 16, have configured riding lawn mower.
[0016]
As shown in FIGS. 1 and 2, the vehicle body B of the work vehicle is constituted by a vehicle body body composed of the engine 1 and the transmission case 3 and a vehicle body reinforcement frame 31 positioned on both lateral outer sides of the vehicle body body. is there.
The vehicle body includes the engine 1, a front wheel support frame 5 whose rear end is connected to a lower portion of the engine 1 by a connecting bolt 5a, a clutch housing 2 connected to the rear portion of the engine 1, and the clutch housing. The transmission case 4 whose front end side is connected to the rear portion of the transmission case 2 by a connection bolt 4a, and the front case connected to the rear end side of the transmission case 4 by a connection bolt 4b and connected to the front portion And the transmission case 3 provided with a rear axle case 3c extending from the rear side to both lateral outer sides.
[0017]
The transmission case 4 has a rotating shaft that transmits the output of the clutch housing 2 to the continuously variable transmission 9 and a rotating shaft that transmits the front wheel output of the transmission case 9 to the front axle case 7. It is made of a bent sheet metal formed into an open channel shape.
[0018]
As shown in FIGS. 2, 6, etc., the left and right vehicle body reinforcing frames 31 are connected to the lateral side of the lower part of the clutch housing 2 by the connecting bolt 33 at the front end side and the lateral side of the intermediate part of the transmission case 4 at the rear end side. The front frame portion 31F is connected to the outer surface side by a connecting bolt 35, the front end side is connected to the rear end portion of the front frame portion 31F by the connecting bolt 32, and the intermediate portion is connected to the connecting portion 36 of the transmission case 4 by the connecting bolt 37. And the rear end side is constituted by a rear frame portion 31R connected to the lateral outer surface side of the transmission case 3 by a connecting bolt 34.
[0019]
The link mechanism L is configured as shown in FIG. 1, FIG. 3, FIG.
That is, the front end side is pivotably and detachably connected to the support portion 5b included in the front wheel support frame 5, and the rear end side is pivotally connected to the bracket 16a located at the front portion of the mower deck 16 of the lawn mower M. The front swing link 18, the link support portion 31 a provided in the front frame portion 31 F of the vehicle body reinforcement frame 31 on the left side of the vehicle body, the front end side is rotatably connected, and the rear end side is located at the rear portion of the mower deck 16. The rear swing link 19 rotatably connected to the bracket 16b, the link support portion 31a provided on the front frame portion 31F of the vehicle body reinforcement frame 31 on the right side of the vehicle body, the front end side is rotatably connected, and the rear end The rear swing link 19 whose side is rotatably connected to the link bracket 16b located at the rear of the moor deck 16 is separated from both lateral outer sides of the transmission case 4. And a pair of left and right lift arms 20 supported by the transmission case 4 so as to be swingable up and down, a lift link 21 connecting the rear swing link 19 on the left side of the vehicle body and the lift arm 20, and a right side of the vehicle body Each of the rear swing link 19 and the lift arm 20 is connected to a lift link 21 and a lift cylinder C positioned inside the transmission case 3.
[0020]
As shown in FIGS. 3 and 4, the left and right lift arms 20, 20 have a base end side of one lift arm 20 at one end side and a base end side of the other lift arm 20 at the other end side, respectively. A single rotation support shaft 40 that is supported so as to rotate integrally is rotatably mounted across a pair of left and right support portions 41 provided at the lower portion of the transmission case 4 so that the rotation support shaft is supported with respect to the vehicle body B. 40 is pivotally attached and swings up and down in conjunction with the rotation shaft 40 around the axis.
As shown in FIGS. 4 and 6, the rotary support shaft 40 is detachably fitted on the support shaft main body with one lift arm 20 fixed to one end and the other end of the support shaft main body. And a cylindrical shaft portion 40a that is interlocked and connected to the support shaft main body, and the other lift arm 20 is fixed to one end portion. The left and right support portions 41 include a metal plate bracket 41a whose one end is fixed to the transmission case 4, and an inner surface side of the bracket 41a so as to increase a support area for receiving and acting on the rotation support shaft 40 of the support portion 41. And a thick metal plate 41b that is bolt-connected to each other.
[0021]
In the lift cylinder C, the base end side is connected to the rotation support shaft 40 between the support portions 41 so as to be integrally rotatable by a connection pin 43, and the rod is connected to an operation arm 44 that rotates the rotation support shaft 40. And a single-acting hydraulic cylinder having a tube connected to a cylinder bracket supported by the transmission case 3, the driving force by the supplied pressure oil, and the gravity of the lawnmower M applied to the lift arm 20. Thus, the rotation support shaft 40 is rotated to swing the left and right lift arms 20 and 20.
[0022]
As shown in FIGS. 4 and 5, a positioning member 47 is formed by fixing a sheet metal member to an end portion of the rotating shaft 40 which is a main shaft body and an end portion of the cylindrical shaft portion 40a. In addition, the upper and lower vehicle body reinforcement frames 31 are provided with notches on the upper edge sides of the rear frame portions 31R so as to provide an ascending stopper portion 48 and a descending stopper portion 49. Stopper means for setting the lowering limit is configured.
That is, as the lift arm 20 swings and the rotation support shaft 40 rotates, each positioning portion 47 rotates together with the rotation support shaft 40, and one end portion 47 a of each positioning portion 47 is connected to this positioning portion 47. A corresponding upper stopper portion 48 of the vehicle body reinforcing frame 31 is brought into contact, or the other end portion 47 b of each positioning portion 47 is brought into contact with a lowering stopper portion 49 of the vehicle body reinforcing frame 31 corresponding to the positioning portion 47. When the positioning part 47 comes into contact with the ascending stopper part 48, the ascending stopper part 48 puts a stop on the rotating support shaft 40 so as not to rotate any further, thereby setting the swing position of the lift arm 20 at the ascending limit. Set as. When the positioning part 47 comes into contact with the lowering stopper part 49, the lowering stopper part 49 stops the rotation support shaft 40 so that it does not rotate any more, thereby setting the current swing position of the lift arm 20 as the lowering limit. Set.
[0023]
In other words, the link mechanism L switches the control valve of the lift cylinder C to move the lawn mower M up and down by the driving force of the lift cylinder C and the weight of the lawn mower M.
That is, when the control valve is switched to the ascending side, the lift cylinder C is driven to the extending side by the pressure oil supplied, and the rotating support shaft 40 is rotated to the ascending side to swing the left and right lift arms 20 to the ascending side. Operation. Then, the left and right lift arms 20 pull up the lift link 21 and swing the rear swing link 19 upward with respect to the vehicle body B. Accordingly, the front swing link 18 swings upward with respect to the vehicle body B, and the lawnmower M is lifted. At this time, when each positioning portion 47 of the rotation support shaft 40 of the lift arm 20 comes into contact with the rising stopper portion 48 corresponding to the positioning portion 47, each lift arm 20 becomes the rising limit, and the lawnmower M is further lifted. Disappear.
[0024]
When the control valve is switched to the lowering side, the lift cylinder C can be drained, and the rotary support shaft 40 is rotated to the lowering and rising side by the weight of the lawn mower M, so that the left and right lift arms 20 are moved to the lowering side. Swing operation. Then, the left and right lift arms 20 lower the lift link 21 and swing the rear swing link 19 downward relative to the vehicle body B. As a result, the front swing link 18 swings downward with respect to the vehicle body B, and the lawnmower M is lowered. At this time, when each positioning portion 47 of the rotation support shaft 40 of the lift arm 20 comes into contact with the lowering stopper portion 49 corresponding to this positioning portion 47, each lift arm 20 becomes the lowering limit, and the lawnmower M is further lowered. Disappear. In this state, when the grounding gauge ring 17 as shown in FIG. 1 of the lawn mower M enters the concave portion of the ground and the lawn mower M is in a suspended state, the positioning portions 47 of the rotary support shaft 40 with respect to the lowering stopper portions 49 are arranged. For hitting, the lawn mower M is suspended and supported while the left and right lift arms 20, 20 are supported by the vehicle body reinforcing frame 31 so as not to descend any further.
[0025]
The hydraulic pipe 51 that connects the control valve of the lift cylinder C to the hydraulic pump and the hydraulic pipe 52 that connects the control valve of the lift cylinder that swings the rear lift arm 13 to the hydraulic pump are shown in FIG. It is fixed to the vehicle body B by the fixing structure shown in FIG.
That is, the hydraulic pipes 51 and 52 are fixed to the stay 53 by the pipe band 54 that is locked to the stay 53 through the band hole 53 a of the stay 53 that is fixed to the outer surface side of the transmission case 4. An inclined portion 53b is provided at the leading end side of the stay 53, and the inclined portion 53b prevents the hydraulic pipes 51 and 52 from coming off the stay 53 by suppressing the displacement movement of the hydraulic pipes 51 and 52. ing.
[0026]
As shown in FIG. 9, a packaging case 60 for storing a work vehicle during transportation is configured by combining a plurality of square pipe members along the front and rear and up and down directions of the vehicle body. As shown in FIG. 10, a takeout guide is constituted by a guide main body 65 made of an angle material and an attachment rod 66 extending from the back of the guide main body 65. This take-out guide is used when taking out the packing case 60 loaded in the container 68, and is configured in detail as follows.
[0027]
That is, when the packing case 60 is taken out from the container 68, the fork claws of the unloading vehicle are inserted into the nail attachment holes 61 as shown in FIG. At this time, the take-out guide mounting rod 66 is inserted into the guide mounting hole 62 as shown in FIG. 10 formed by the holes of the square pipe material existing on both sides of the lower portion of the packing case 60. As a result, take-out guides are mounted on both lateral sides of the packing case 60. Then, the side wall surface of the container 68 is an uneven surface in which ridges 69 along the vertical direction of the container are aligned in the take-out direction of the packing case 60, and when the take-out guide is not attached to the packing case 60, the packing case However, when the take-out guide is attached, the take-out guide is supported by the inclined guide surface 65a of the guide main body 65 so as to be packed in the packing case. 60 corners are made difficult to catch on the ridge 69. Thereby, the work vehicle stored in the packing case 60 can be smoothly and efficiently removed from the container 68.
[0028]
[Another embodiment]
In addition to the lawn mower M, the present invention can also be applied to work vehicles that connect various working devices such as a cleaning device that sucks dust and the like. Therefore, the lawnmower M and the cleaning device are collectively referred to as the ground work device M.
[Brief description of the drawings]
FIG. 1 is a side view of the entire riding lawn mower. FIG. 2 is a side view of a vehicle body. FIG. 3 is a cross-sectional view of a structure for attaching a link mechanism of a vehicle body. 5] Side view of the stopper means [Fig. 6] Exploded perspective view of the vehicle body and the lift arm support shaft [Fig. 7] Cross-sectional view of the hydraulic hose support structure [Fig. 8] Plan view of the hydraulic hose support structure [Fig. Side view showing the packing state [Fig. 10] Perspective view of the take-out guide [Fig. 11] Explanatory drawing showing how to use the take-out guide
2 Clutch housing 3 Transmission case 4 Transmission case 20 Lift arm 40 Rotating support shaft 47 Positioning portion 48 Lifting stopper portion 49 Lowering stopper portion M Ground working device C Lift cylinder B Car body

Claims (2)

A pair of left and right lift arms to which a ground work device located below the vehicle body is connected so as to be movable up and down are attached to the vehicle body by a single rotation support shaft so as to be swingable up and down, and the rotation support shaft is operated to rotate the rotation support shaft. A work vehicle including a lift cylinder that swings a pair of left and right lift arms,
Positioning portions are provided on both end sides of the rotation spindle so as to be integrally rotatable, a pair of ascending stopper portions that respectively contact the pair of left and right positioning portions to set a lift limit of the lift arm, and the pair of left and right positioning A work vehicle in which the vehicle body includes a pair of lowering stopper parts that contact the parts separately to set the lowering limit of the lift arm. A vehicle body having a transmission case for connecting the vehicle body to a clutch housing and a transmission case, the vehicle body is positioned separately on both lateral sides of the vehicle body, one end side is the clutch housing, and the other end side is the transmission case. 2. The work vehicle according to claim 1, further comprising a pair of vehicle body reinforcement frames respectively connected to the vehicle body reinforcement frame, wherein the vehicle body reinforcement frame includes the ascending stopper portion and the descending stopper portion.

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