JP7092343B2 - Working machine traction device, working machine steering device and working machine equipped with these - Google Patents

Description

INDUSTRIAL APPLICABILITY The present invention includes a work machine traction device, a work machine steering device, and a work machine provided with these, which connect a drawbar installed at the rear end of the tractor and a work machine towed by the tractor to steer the work machine. It is about.

Working machines towed by tractors include, for example, boom sprayers that spray liquid fertilizers, pesticides, and the like. In order to grow the crops to be grown evenly and to protect them from pests evenly, liquid fertilizers and pesticides must be sprayed evenly. However, since the boom sprayer of the type towed by the tractor is simply towed by the tractor and travels, the boom sprayer turns later than the turn of the tractor. For this reason, it is difficult to operate when turning at the edge of the field, and the tractor meanders, which makes the spraying work difficult, which causes uneven spraying.

Therefore, conventionally, an invention relating to a steering device for a working machine towed by such a tractor has been proposed. For example, in Japanese Patent Application Laid-Open No. 2007-191139 filed by the applicant of the present application, a hitch angle sensor for detecting a hitch angle formed by the working machine with respect to a hitch, and the hitch and the working machine connected to the hitch angle. The hitch angle increasing / decreasing means for increasing / decreasing, the storage means for storing the hitch angle as a reference offset value when the traveling direction of the working machine matches the traveling direction of the tractor, and the numerical value changed by the operation of the tractor. When the turning status detecting means for detecting the turning status of the tractor and the turning status detecting means detect the start of turning based on the numerical value changed by the operation of the tractor, the work machine controls the turning angle increasing / decreasing means to control the turning direction of the tractor. When the hitch angle is increased or decreased so as to be outward with respect to the tractor and the turning state detecting means detects the end of turning based on the numerical value changed by the operation of the tractor, the hitch angle increasing or decreasing means is controlled and the hitch angle is a reference offset. A steering device for a working machine is disclosed, which has a steering control means for increasing or decreasing the value so as to be a value. (Patent Document 1).

Japanese Unexamined Patent Publication No. 2007-191139

According to the invention described in Patent Document 1, the steerability of the working machine is improved and uneven spraying of liquid fertilizer and the like can be suppressed in each stage, but on the other hand, the tractor traveling in the field vibrates in the vertical direction due to undulations. Then, it was transmitted to the working machine, and the front-back position of the working machine was tilted in the vertical direction, that is, so-called pitching may cause uneven spraying. Therefore, there is a new problem of suppressing the pitching of the working machine generated by the transmission of such vertical vibration of the tractor. Further, in a tractor-type boom sprayer, when the chemical liquid tank is full of chemical liquid or the like, the load due to the load of the hitch or the attachment portion between the hitch and the tractor and the connection portion on the working machine side connecting the hitch is large. In recent years, as the size of the towed boom player has increased, the load due to the load has become even larger. Furthermore, although the field and farm roads around the field are being improved and the moving speed is increasing, when traveling on an unexpected rough road due to a depression or the like, the load condition applied to the hitch or the like is extremely deteriorated due to the impact, and the hitch Etc. may be damaged.

The present invention has been made to solve the above problems, and suppresses pitching of the working machine generated by the vertical vibration of the tractor, and is caused by the load on the working machine side applied to the hitch or the like. It is an object of the present invention to provide a work machine traction device, a work machine steering device, and a work machine equipped with these, which can reduce the burden.

The work machine traction device according to the present invention includes a drawbar installed at the rear end of the tract and a work machine towed by the tractor in order to solve the problem of cushioning the vertical vibration of the tractor transmitted to the work machine. A work machine traction device that connects the work machine to a left-right rotation support shaft provided at the tip of the work machine with its axis oriented in a substantially vertical direction, and a left-right rotation support shaft that is rotatably supported in the left-right direction. A vertical rotation support shaft provided at the tip of the working machine side hitch with its axis perpendicular to the longitudinal direction of the working machine side hitch so as to be substantially horizontal, and the vertical rotation thereof. A tractor-side hitch having a drawbar connecting portion that is rotatably supported by a support shaft at a substantially central position in the longitudinal direction and connected to the drawbar at its tip, a side position of the working machine-side hitch, and the working machine. The left and right steering hydraulic cylinders that steer the work machine in the left-right direction by being connected to and expanding and contracting, and the tractor side hitch provided between the rear end of the tractor side hitch and the work machine side hitch. It has a vertical vibration cushioning member that cushions vibration in the vertical direction.

Further, as one aspect of the present invention, in order to solve the problem of facilitating the cushioning performance of the vertical vibration cushioning member, the vertical vibration cushioning member is at the rear end of the vertical rotation support shaft and is said to be the same. The distance along the longitudinal direction from the vertical rotation support shaft may be provided at a position substantially equal to the distance along the longitudinal direction from the vertical rotation support shaft to the drawbar connecting portion.

Further, as one aspect of the present invention, in order to solve the problem of cushioning vibration in either the vertical direction, the work machine side hitch is formed in a tubular shape with an open tip, and the tractor side hitch is formed. Is supported by the vertical rotation support shaft in a state of being inserted into the working machine side hitch from the opening, and the vertical vibration cushioning member is attached to the lower surface of the rear end of the tractor side hitch and the working machine side hitch. A lower cushioning member that is connected to the inner lower surface and cushions vibration when the rear end of the tractor side hitch sways downward, and a lower cushioning member that is provided on the upper surface of the rear end of the tractor side hitch and is provided on the upper surface of the rear end of the tractor side hitch. It may have an upper cushioning member that cushions the vibration when the rear end of the tractor side hitch swings upward by being sandwiched with the inner upper surface of the tractor.

Further, as one aspect of the present invention, in order to solve the problem of adjusting the strength of the reaction force against vertical vibration, the lower cushioning member is arranged between the lower cushioning member and the inner lower surface of the work machine side hitch, and the same is provided. A reaction force adjusting member that adjusts the strength of the reaction force against the vertical vibration of the rear end of the tractor side hitch by the lower cushioning member by increasing or decreasing the thickness may be provided.

Further, as one aspect of the present invention, in order to solve the problem of facilitating the attachment, removal and replacement of the lower cushioning member and the reaction force adjusting member, the lower cushioning member is arranged on the inner lower surface of the work machine side hitch. An opening may be formed at the position, and a cushioning member connecting lid to which the lower cushioning member is connected may be detachably attached to the opening.

The work machine steering device according to the present invention is the work to be pulled by the tractor by the left and right steering hydraulic cylinders in the work machine traction device in order to solve the problem that the work machine is steered and controlled by the left and right steering hydraulic cylinders. A work machine steering device that steers a machine, the hitch angle detecting means for detecting the hitch angle made by the work machine with respect to the hitch on the work machine side, and the drawbar angle made by the drawbar with respect to the hitch on the tractor side. The left and right steering hydraulic cylinders are expanded and contracted based on the drawbar angle detecting means to be detected, the hitch angle detected by the hitch angle detecting means, and the drawbar angle detected by the drawbar angle detecting means, and the working machine is steered. It has a steering control means, and the drawbar angle detecting means is rotatably installed in the left-right direction at the tip of the tractor-side hitch and is connected to the tractor-side hitch to turn left and right. The drawbar following arm that follows the movement, the drawbar angle transmission link that transmits the rotation angle of the drawbar following arm in the left-right direction, and the angle that detects the rotation angle of the drawbar following arm transmitted by this drawbar angle transmission link. It is the tip of the tractor side hitch that is equipped with a sensor body and can avoid interference with the power extraction mechanism that takes out the power of the tractor for driving the work equipment, and is either left or right. It is installed at the side position of.

Further, as one aspect of the present invention, in order to solve the problem of improving the followability of the drawbar follower arm to the drawbar, the drawbar follower arm has a size in which the drawbar follower arm provided in the drawbar can be inserted. It may be slidably inserted in the front-rear direction with respect to the arm insertion frame portion formed in the shape of a horizontally long elliptical frame.

Further, as one aspect of the present invention, in order to solve the problem of preventing the drawbar following arm from interfering with the drawbar, the drawbar following arm is installed so as to be rotatable in the left-right direction at the position on the upper surface of the tip of the tractor side hitch. In addition, the tip side thereof may be bent upward so as to avoid interference with the drawbar.

Further, as one aspect of the present invention, in order to solve the problem of avoiding interference between the drawbar angle transmission link and the angle sensor main body and the drawbar following arm, the drawbar angle transmission link is rotated in the left-right direction of the drawbar following arm. The rotation interlocking arm that is integrally interlocked with the motion, the angle input arm that inputs the rotation angle to the angle sensor main body, and the left and right of the rotation interlocking arm that is connected to the rotation interlocking arm and the angle input arm. It has an angle transmission arm that transmits the rotation of the direction to the angle input arm, and the angle transmission arm is curved outward so as to avoid interference with the angle sensor main body and the drawbar following arm. You may be doing it.

The working machine according to the present invention has the vertical rotation support shaft and the vertical vibration cushioning member in order to solve the problem of suppressing pitching of the working machine due to vertical vibration of the tractor and reducing the load on the working machine side. The working machine traction device, or the working machine traction device and the working machine steering device.

According to the present invention, it is possible to suppress the pitching of the working machine generated by the transmission of the vertical vibration of the tractor, and to reduce the load on the working machine side applied to the hitch or the like.

It is a perspective view which shows one Embodiment in the state which the working machine which concerns on this invention is connected to a tractor. It is a side view which shows the state which connected the working machine of this embodiment to a tractor. It is a top view which shows the state which connected the working machine of this embodiment to a tractor. However, the description of the left boom of the working machine is omitted. It is a side view which shows the working machine traction device of this embodiment. It is a bottom view which shows the working machine traction device of this embodiment. It is a block diagram which shows the structure of the work machine steering apparatus of this embodiment. It is a perspective view which shows the draw bar angle detecting means in this embodiment. It is a top view which shows the draw bar angle transmission link of the draw bar angle detection means in this embodiment.

Hereinafter, an embodiment of a working machine traction device, a working machine steering device, and a working machine provided with these according to the present invention will be described with reference to the drawings.

The work machine 1 is a vehicle for agricultural work that is towed by a tractor 10 and travels, and in the present embodiment, it is a boom sprayer as shown in FIGS. 1 to 3. The working machine 1 of the present embodiment has a working machine traction device 2 for connecting to the tractor 10 and a working machine steering device 3 for steering the working machine 1 using the working machine traction device 2. Hereinafter, each configuration will be described.

The work machine traction device 2 of the present embodiment connects the draw bar 11 installed at the rear end of the tractor 10 and the work machine 1 towed by the tractor 10, and as shown in FIG. 4, the work machine traction device 2 is described. A left-right rotation support shaft 4 provided at the tip of the work machine 1, a work machine side hitch 5 rotatably supported in the left-right direction by the left-right rotation support shaft 4, and a tip 51 of the work machine side hitch 5. A vertical rotation support shaft 6 provided in the above, a tractor side hitch 7 rotatably supported by the vertical rotation support shaft 6, a left-right steering hydraulic cylinder 8 for steering the working machine 1 in the left-right direction, and the above. It has a vertical vibration cushioning member 9 that suppresses vertical vibration of the tractor side hitch 7.

The left-right rotation support shaft 4 is a support shaft for rotatably supporting the work machine 1 in the left-right direction, and as shown in FIGS. 1 to 3, the axis line thereof is substantially perpendicular to the tip of the work machine 1. It is provided in a state facing the.

The work machine side hitch 5 connects the tractor 10 and the work machine 1 together with the tractor side hitch 7, and is rotatably supported in the left-right direction with respect to the left-right rotation support shaft 4. The work machine side hitch 5 in the present embodiment has a substantially rectangular vertical cross section with the tip 51 side opened by cutting a steel plate having a predetermined thickness with a laser cutting machine and bending the plate material. It is formed in the shape of a cylinder.

Further, on the lower surface 52 of the work machine side hitch 5, an opening 53 for facilitating attachment, removal, or replacement of the reaction force adjusting member 93 described later and a cushioning member connecting lid 54 attached to the opening 53 are provided. Have.

The opening 53 is an inner lower surface 58 of the work machine side hitch 5 and is opened at a position where the lower cushioning member 91, which will be described later, is arranged. Further, in the present embodiment, as shown in FIGS. 4 and 5, the left and right side surfaces 57 are continuously opened in order to provide the lower cushioning member 91 whose left and right width with respect to the traveling direction is larger than the width of the work machine side hitch 5. Has been done.

The cushioning member connecting lid 54 is for attaching the lower cushioning member 91, and as shown in FIG. 5, a portion formed larger in the front-rear direction than the opening 53 and overlapped with the lower surface 52 of the work machine side hitch 5. It is detachably fixed by a plurality of bolts 55 in the above.

The vertical rotation support shaft 6 is a support shaft for rotatably supporting the tractor side hitch 7 in the vertical direction, and its axis is set in the longitudinal direction of the work machine side hitch 5 at the tip 51 of the work machine side hitch 5. It is installed so as to be orthogonal to the horizontal direction. As shown in FIG. 4, the vertical rotation support shaft 6 in the present embodiment is provided at a position substantially central to the upper and lower sides of the opening in the vicinity of the opening end of the tip 51 of the work machine side hitch 5.

The tractor-side hitch 7 connects the tractor 10 and the working machine 1 together with the working machine-side hitch 5, and is vertically rotatable and vertically rotatably supported by the vertically moving rotation support shaft 6 at a substantially central position in the longitudinal direction thereof. Has been done. The tractor-side hitch 7 in the present embodiment is formed in a shape thinner than the inside of the work-machine side hitch 5 so as to be inserted into the tubular work-machine-side hitch 5. The tractor side hitch 7 is supported by the vertical movement rotation support shaft 6 with the rear end 71 side inserted into the work machine side hitch 5, and the rear end 71 is the inner lower surface of the work machine side hitch 5. It swings up and down between 58 and the inner upper surface 56.

Further, the tip 72 of the tractor side hitch 7 has a drawbar connecting portion 73 to be connected to the drawbar 11, and in the present embodiment, a connecting pillar provided along a substantially vertical direction at the rear end of the drawbar 11 (not shown). ) Is fitted into the connecting hole. The configuration for connecting to the drawbar 11 is not limited to that of a connecting pillar, and may be configured to be connectable to, for example, a substantially spherical protrusion provided on the drawbar 11, a so-called hitch ball.

The left-right steering hydraulic cylinder 8 is for steering the working machine 1 in the left-right direction, and includes a hydraulic cinder that expands and contracts by hydraulic control. The left and right steering hydraulic cylinders 8 are connected to the side surface 57 position of the work machine side hitch 5 and the work machine 1. Specifically, a cylinder connecting portion 81 projecting outward is provided at the position of the side surface 57 on the right side with respect to the traveling direction of the work machine side hitch 5, and each end of the left and right steering hydraulic cylinder 8 is the cylinder. The connecting portion 81 and the position on the right side of the center of the tip of the working machine 1 are rotatably connected to each other. As a result, the left and right steering hydraulic cylinders 8 are contracted to steer the work machine 1 so as to face the left side with respect to the traveling direction of the tractor 10, and the tractor 10 is steered so as to face the right side by extending.

The vertical vibration cushioning member 9 cushions the vertical vibration of the tractor-side hitch 7, and is provided between the rear end 71 of the tractor-side hitch 7 and the working machine-side hitch 5. As shown in FIG. 4, the vertical vibration shock absorber 9 in the present embodiment has a distance along the longitudinal direction from the vertical rotation support shaft 6 in the longitudinal direction from the vertical rotation support shaft 6 to the drawbar connecting portion 73. It is provided at a position almost equal to the distance along the. As a result, the balance between the force acting on the vertical vibration cushioning member 9 and the displacement in the vertical direction is maintained.

That is, if the distance from the vertical rotation support shaft 6 to the vertical vibration buffer member 9 is shorter than the distance from the vertical rotation support shaft 6 to the drawbar connecting portion 73, the vertical vibration buffer member 9 due to the vertical vibration of the drawbar 11 Although the displacement of is small, the force received by the vertical vibration cushioning member 9 becomes stronger due to the principle of leverage. Therefore, for the vertical vibration cushioning member 9, it is necessary to select a material having high hardness and being hard to be deformed in order to resist the force received. However, the cushioning material having high hardness is difficult to attenuate the vibration and is inferior in durability. On the other hand, if the distance from the vertical rotation support shaft 6 to the vertical vibration buffer member 9 is longer than the distance from the vertical rotation support shaft 6 to the drawbar connecting portion 73, the vertical vibration buffer member 9 due to the vertical vibration of the drawbar 11 It is difficult to suppress the vibration because the displacement of is large. Therefore, in the present embodiment, in consideration of these problems, the installation position of the vertical vibration shock absorber 9 is set to the distance to the vertical rotation support shaft 6 as described above and the distance between the support shaft 6 to the drawbar connecting portion 73. Is determined to be almost equidistant.

Further, as shown in FIG. 4, the vertical vibration shock absorber 9 in the present embodiment can cushion not only the downward sway of the rear end 71 of the tractor side hitch 7 but also the upward sway of the tractor side hitch 7. It has a lower cushioning member 91 connected between the rear end lower surface 74 and the inner lower surface 58 of the working machine side hitch 5, and an upper cushioning member 92 provided on the rear end upper surface 75 of the tractor side hitch 7.

The lower cushioning member 91 is a vertical vibration of the rear end 71 of the tractor side hitch 7, and mainly cushions the vibration when the rear end 71 swings downward, and the tractor side hitch 7 is used. It is connected between the rear end lower surface 74 and the inner lower surface 58 of the working machine side hitch 5. The lower cushioning member 91 in the present embodiment is a rubber cushioning material formed in a substantially cylindrical shape with a hollow inside and a bellows shape in the vertical direction, and cushions vibration by the elastic force of the rubber. And is designed to decay. In the present embodiment, as described above, since the force acting on the rear end 71 of the tractor side hitch 7 due to vibration and the displacement in the vertical direction are balanced, a cushioning material that is flexibly deformed and has high damping performance is used. Can be done. That is, the lower cushioning member 91 in the present embodiment has a large amount of energy that can be absorbed, and can absorb a large load and a large displacement.

The lower cushioning member 91 in the present embodiment is on the inner lower surface 58 side of the working machine side hitch 5, and is located symmetrically on the cushioning member connecting lid 54 provided in the opening 53 of the working machine side hitch 5. Each is connected. Further, a reaction force adjusting member 93 is provided between the lower cushioning member 91 and the cushioning member connecting lid 54. The reaction force adjusting member 93 adjusts the strength of the reaction force against the vertical vibration of the rear end 71 of the tractor side hitch 7 by the lower cushioning member 91, and when the thickness thereof is increased, the lower cushioning member 91 is adjusted. Pressure can be applied in advance to increase the reaction force. On the other hand, if the thickness is reduced, the pressure applied to the lower cushioning member 91 is reduced, and the reaction force can be weakened.

The upper cushioning member 92 is a vertical vibration of the rear end 71 of the tractor-side hitch 7, and mainly cushions the vibration when the tractor-side hitch 7 is shaken upward, and is an upper surface of the rear end of the tractor-side hitch 7. It is provided on the 75 and is sandwiched between the inner upper surface 56 of the work machine side hitch 5. The upper cushioning member 92 in the present embodiment is made of a rubber cushioning material formed in an elliptical column shape.

The lower cushioning member 91 and the upper cushioning member 92 are not limited to the above configurations and materials, and are appropriately selected from those that cushion the vertical vibration of the tractor side hitch 7. Further, the number of the lower cushioning member 91 and the upper cushioning member 92 to be installed is not particularly limited. For example, when the load on the working machine 1 side is relatively light, the lower cushioning member 91 is placed on the cushioning member connecting lid 54. Only one may be installed, and three or more may be installed when the load is relatively heavy. Further, when the working machine 1 has a difference in weight balance between left and right and a difference in vibration between left and right, the lower cushioning member 91 and the upper cushioning member 92 may be arranged asymmetrically.

Next, the working machine steering device 3 of the present embodiment will be described. The work machine steering device 3 of the present embodiment steers the work machine 1 towed by the tractor 10 by the left and right steering hydraulic cylinders 8 in the work machine traction device 2, and has a hitch angle as shown in FIG. It has a hitch angle detecting means 31 for detecting, a drawbar angle detecting means 32 for detecting a drawbar angle, and a steering control means 33 for controlling expansion and contraction of the left and right steering hydraulic cylinders 8 based on the hitch angle and the drawbar angle.

The hitch angle detecting means 31 detects the hitch angle formed by the working machine 1 with respect to the working machine side hitch 5. In the present embodiment, the angle sensor main body 12 is installed at the tip of the working machine 1. The angle input arm is connected to the work machine side hitch 5.

The drawbar angle detecting means 32 detects the drawbar angle formed by the drawbar 11 with respect to the tractor side hitch 7, and in the present embodiment, the drawbar tracking arm 13 that follows the left / right turning motion of the drawbar 11 and the drawbar following. It has a drawbar transmission link 14 that transmits a rotation angle in the left-right direction of the arm 13, and an angle sensor main body 15 that detects the rotation angle transmitted by the drawbar transmission link 14.

The drawbar following arm 13 is rotatably installed in the left-right direction at the tip 72 of the tractor-side hitch 7. As shown in FIGS. 7 and 8, the drawbar following arm 13 of the present embodiment is formed in a hairpin-shaped bent shape, and as shown in FIGS. 4 and 7, the tip end side thereof is with the drawbar 11. It is bent upward to avoid interference. The base end of the drawbar following arm 13 is rotatably installed in the left-right direction at the position on the upper surface of the tip 72 of the tractor-side hitch 7, and can also rotate in the up-down direction. The drawbar following arm 13 is not limited to the one whose tip end side is bent upward, and may have a straight shape or be bent downward as long as there is no problem of interference with the drawbar 11. ..

Further, on the drawbar 11 side, as shown in FIG. 4, an arm insertion frame portion 16 formed in a frame shape having a size capable of inserting the drawbar following arm 13 is provided. Although not shown, the arm insertion frame portion 16 in the present embodiment has a laterally long elliptical opening with an appropriate dimensional allowance with respect to the drawbar following arm 13.

The drawbar following arm 13 is inserted into the arm insertion frame portion 16 and rotates in the left-right direction following the left-right turning operation of the drawbar 11 and slides in the front-rear direction with respect to the arm insertion frame portion 16. It is possible to absorb the displacement due to pitching between the tractor 10 and the work vehicle 1. Further, the drawbar following arm 13 is held at the center position by sliding down along the downward inclination toward the center at the left and right ends of the arm insertion frame portion 16 due to its own weight.

The drawbar transmission link 14 transmits the rotation angle of the drawbar follow-up arm 13 in the left-right direction to the angle sensor main body 15. In the present embodiment, as shown in FIG. 8, the drawbar follow-up arm 13 rotates in the left-right direction. The rotation interlocking arm 141 that is integrally interlocked with the motion, the angle input arm 142 for inputting the rotation angle to be detected in the angle sensor main body 15, and the rotation interlocking arm 141 and the angle input arm 142 are connected to each other. It also has an angle transmission arm 143 that transmits the rotation of the rotation interlocking arm 141 in the left-right direction to the angle input arm 142. The angle transmission arm 143 in the present embodiment is formed in a convex curved shape on the outside so as not to interfere with the angle sensor main body 15 and the drawbar following arm 13.

The angle sensor main body 15 detects the drawbar angle, and the angle input portion is provided with an angle input arm 142 that rotates integrally. The angle sensor main body 15 in the present embodiment is the tip 72 of the tractor side hitch 7 in order to avoid interference with a power extraction mechanism (not shown) that takes out the power of the tractor 10 for driving the work machine 1, and either left or right. It is installed at 76 positions on the side of the tractor. The angle sensor main body 15 in the present embodiment is provided on the right side surface 76 of the tractor side hitch 7 with respect to the traveling direction of the tractor 10.

The steering control means 33 controls the expansion and contraction of the left and right steering hydraulic cylinders 8 based on the hitch angle detected by the hitch angle detecting means 31 and the drawbar angle detected by the drawbar angle detecting means 32 to steer the working machine 1. For example, similarly to the steering control means 33 of the steering device disclosed in Japanese Patent Application Laid-Open No. 2007-191139, the hitch angle when the tractor 10 coincides with the traveling direction is stored as a reference offset value. When the start of turning of the tractor 10 is detected based on the detection result of the drawbar angle detecting means 32, the left and right steering hydraulic cylinders 8 are controlled to increase or decrease the hitch angle so that the working machine 1 faces outward with respect to the turning direction of the tractor 10. Then, when the end of turning of the tractor 10 is detected based on the detection result of the drawbar angle detecting means 32, the left and right steering hydraulic cylinders 8 are controlled to increase / decrease the hitch angle so as to be the reference offset value.

Next, the operation of each configuration in the work machine traction device 2, the work machine steering device 3, and the work machine 1 provided with these will be described.

The work machine traction device 2 connects the work machine 1 to the drawbar 11 installed at the rear end of the tractor 10. When the tractor 10 travels in this state, the working machine 1 is towed and travels following the tractor 10.

If there are undulations in a traveling field or the like, the tractor 10 vibrates in the vertical direction accordingly. The vertical vibration of the tractor 10 is transmitted to the work equipment traction device 2 via the drawbar 11 provided at the rear end.

In the working machine traction device 2 of the present embodiment, the vertical vibration of the tractor 10 transmitted via the drawbar 11 is buffered. Specifically, the vertical vibration of the tip 72 side of the tractor side hitch 7 is transmitted to the rear end 71 of the tractor side hitch 7 by rotating around the vertical rotation support shaft 6. At this time, the vibration on the rear end 71 side of the tractor side hitch 7 is buffered by the vertical vibration buffer member 9 and the transmission to the work equipment side hitch 5 is suppressed. In the present embodiment, the vertical vibration buffering member 9 is provided on either the upper or lower side of the rear end 71 of the tractor side hitch 7, so that the vibration in the vertical direction can be buffered. In the present embodiment, as the lower cushioning member 91, a cushioning material that is flexibly deformed and has high damping performance is used, so that vibration can be suppressed and damping can be performed quickly.

If the reaction force of the lower cushioning member 91 is weak and the vibration is difficult to be damped, the reaction force adjusting member 93 is attached or thickened between the lower cushioning member 91 and the inner lower surface 58 of the work machine side hitch 5. Is replaced with the increased reaction force adjusting member 93 to increase the reaction force. On the contrary, when the reaction force by the lower cushioning member 91 is strong and the vibration is directly transmitted, the reaction force adjusting member 93 is removed or replaced with a reaction force adjusting member 93 having a reduced thickness to weaken the reaction force. In the present embodiment, the cushioning member connecting lid 54 can easily attach, remove, or replace the reaction force adjusting member 93 having an appropriate thickness.

In this way, by using the working machine traction device 2 to prevent the vertical vibration of the tractor 10 from being transmitted to the working machine 1 side, for example, when the working machine 1 is a boom sprayer, a chemical solution (herbicide or fungicide). (Diluted pesticides such as) and liquid fertilizer (liquid fertilizer that is a nutrient necessary for crop growth) can be evenly sprayed.

Further, when the tractor 10 makes a turning operation in the left-right direction, the working machine steering device 3 steers the working machine 1.

In the drawbar angle detecting means 32, the drawbar following arm 13 rotates following the turning of the drawbar 11. The rotation of the drawbar following arm 13 is transmitted to the angle sensor main body 15 by the drawbar angle transmission link 14, and the drawbar angle is detected. At this time, since the drawbar following arm 13 slides in the front-rear direction with respect to the arm insertion frame portion 16, it is possible to smoothly follow the turning of the drawbar 11 even if it receives vibration or the like. Further, since the tip end side of the drawbar following arm 13 is bent upward, it does not buffer with the drawbar 11.

The steering control means 33 steers the work machine 1 by controlling the expansion and contraction of the left and right steering hydraulic cylinders 8 based on the hitch angle detected by the hitch angle detecting means 31 and the drawbar angle detected by the drawbar angle detecting means 32. At this time, in the drawbar angle detecting means 32, the angle sensor main body 15 is provided at a position extremely close to the drawbar connecting portion 73 which is the center of the drawbar angle, and the drawbar following arm 13 directly detects the drawbar angle, so that the steering is steered. When controlling the expansion and contraction of the left and right steering hydraulic cylinder 8 of the control means 33, it is not necessary to make a correction based on the difference in the positions of the drawbar angle detecting means 32 and the drawbar connecting portion 73.

According to the working machine traction device 2, the working machine steering device 3, and the working machine 1 provided with these, the following effects can be obtained.
1. 1. By supporting the tractor-side hitch 7 so as to be rotatable in the vertical direction and providing the vertical vibration buffer member 9 at the rear end 71, it is possible to suppress pitching of the work machine 1 steered by the left-right steering hydraulic cylinder 8. ..
2. 2. Since the vertical vibration cushioning member 9 can be deformed relatively flexibly and a cushioning material having high damping performance can be used, the vibration suppressing effect can be enhanced and the durability can be improved.
3. 3. Since it can be buffered against any shaking up and down, the durability of the cushioning members 91 and 92 arranged above and below can be extended.
4. The strength of the reaction force of the 91 lower cushioning member 91 can be easily adjusted by the reaction force adjusting member 93 and the cushioning member connecting lid 54 connecting the reaction force adjusting member 93.
5. By arranging the angle sensor main body 15 of the drawbar angle detecting means 32 at the side surface 76 of the tractor side hitch 7, it is possible to avoid interference with the power extraction mechanism that takes out the power of the tractor 10 for driving the work machine 1. can. Therefore, it can be applied to various tractors 10 and working machines 1.
6. In the drawbar angle transmission link 14, the angle transmission arm 143 is curved so that interference with the angle sensor main body 15 and the drawbar tracking arm 13 can be avoided.

The working machine traction device, the working machine steering device, and the working machine provided with these according to the present invention are not limited to the above-described embodiments, and can be appropriately changed. For example, the working machine 1 is not limited to the boom sprayer, but is not limited to a manual spreader for spraying compost, a towed broad caster for spraying fertilizer, various harvesters such as potato harvesters, or a trailer vehicle for transporting the harvested material. , Can be widely applied to towing agricultural machinery.

1 Work machine 2 Work machine traction device 3 Work machine steering device 4 Left and right rotation support shaft 5 Work machine side hitch 6 Vertical rotation support shaft 7 Tractor side hitch 8 Left and right steering hydraulic cylinder 9 Vertical vibration shock absorber 10 Tractor 11 Drawer 12 Angle Sensor body 13 Drawer following arm 14 Drawer angle transmission link 15 Angle sensor body 16 Arm insertion frame 31 Hitch angle detecting means 32 Drawer angle detecting means 33 Steering control means 51 Tip 52 Bottom 53 Opening 54 Cushioning member connection lid 55 Bolt 56 Top 57 Side 58 Inner lower surface 71 Rear end 72 Tip 73 Drawer connecting part 74 Rear end lower surface 75 Rear end upper surface 76 Side surface 81 Cylinder connecting part 91 Lower cushioning member 92 Upper cushioning member 93 Reaction force adjusting member 141 Rotational interlocking arm 142 Angle input arm 143 Angle transmission arm

Claims (10)

A work machine towing device that connects a drawbar installed at the rear end of a tractor to a work machine towed by the tractor.
A left-right rotation support shaft provided at the tip of the working machine with its axis oriented in a substantially vertical direction,
The work machine side hitch that is rotatably supported in the left-right direction by this left-right rotation support shaft,
A vertical rotation support shaft provided at the tip of the work machine side hitch so that its axis line is orthogonal to the longitudinal direction of the work machine side hitch so as to be substantially horizontal.
A tractor-side hitch having a drawbar connecting portion that is rotatably supported by the vertical rotation support shaft at a substantially central position in the longitudinal direction and is connected to the drawbar at its tip.
A left-right steering hydraulic cylinder that steers the work machine in the left-right direction by expanding and contracting with the side position of the work machine side hitch and the work machine.
The working machine traction device having a vertical vibration buffering member provided between the rear end of the tractor side hitch and the working machine side hitch to cushion the vertical vibration of the tractor side hitch. The vertical vibration shock absorber is at the rear end from the vertical rotation support shaft, and the distance along the longitudinal direction from the vertical rotation support shaft is the longitudinal direction from the vertical rotation support shaft to the drawbar connecting portion. The working machine traction device according to claim 1, which is provided at a position substantially equal to the distance along the above. The work machine side hitch is formed in a tubular shape with an opening at the tip, and the tractor side hitch is supported by the vertical rotation support shaft in a state of being inserted into the work machine side hitch from the opening. Ori,
The vertical vibration shock absorber
A lower cushioning member that is connected between the lower surface of the rear end of the tractor side hitch and the inner lower surface of the work machine side hitch and cushions vibration when the rear end of the tractor side hitch sways downward.
It has an upper cushioning member provided on the upper surface of the rear end of the tractor side hitch and sandwiched with the inner upper surface of the work machine side hitch to cushion the vibration when the rear end of the tractor side hitch swings upward. , The working machine traction device according to claim 1 or 2. It is arranged between the lower cushioning member and the inner lower surface of the working machine side hitch, and by increasing or decreasing the thickness thereof, the lower cushioning member adjusts the strength of the reaction force against the vertical vibration of the rear end of the tractor side hitch. The work machine traction device according to claim 3, further comprising a reaction force adjusting member for adjustment. An opening is formed at the arrangement position of the lower cushioning member on the inner lower surface of the work machine side hitch, and a cushioning member connecting lid to which the lower cushioning member is connected is detachably attached to the opening. , The working machine traction device according to claim 3 or 4. The work equipment steering device for steering the work machine to be pulled by the tractor by the left and right steering hydraulic cylinders in the work equipment traction device according to any one of claims 1 to 5.
A hitch angle detecting means for detecting a hitch angle formed by the working machine with respect to the working machine side hitch, and a hitch angle detecting means.
A drawbar angle detecting means for detecting the drawbar angle formed by the drawbar with respect to the tractor side hitch, and a drawbar angle detecting means.
It has a steering control means for steering the working machine by controlling the expansion and contraction of the left and right steering hydraulic cylinders based on the hitch angle detected by the hitch angle detecting means and the drawbar angle detected by the drawbar angle detecting means. And
The drawbar angle detecting means
A drawbar following arm that is installed so as to be rotatable in the left-right direction at the tip of the tractor-side hitch and that follows the left-right turning operation of the drawbar connected to the tractor-side hitch.
A drawbar angle transmission link that transmits the left-right rotation angle of this drawbar follow-up arm,
It is equipped with an angle sensor main body that detects the rotation angle of the drawbar following arm transmitted by this drawbar angle transmission link, and also includes.
The angle sensor body is the tip of the tractor side hitch capable of avoiding interference with a power extraction mechanism that takes out the power of the tractor for driving the work machine, and is installed at either the left or right side surface position. Work equipment steering device. The drawbar following arm is slidably inserted in the front-rear direction with respect to an arm insertion frame portion formed in a horizontally long elliptical frame having a size capable of inserting the drawbar following arm provided in the drawbar. The working machine steering device according to claim 6. The drawbar following arm is rotatably installed in the left-right direction at the position on the upper surface of the tip of the tractor side hitch, and the tip side thereof is bent upward so as to avoid interference with the drawbar. 6 or the work equipment steering device according to claim 7. A rotation interlocking arm in which the drawbar angle transmission link is integrally interlocked with the left-right rotation of the drawbar follow-up arm, an angle input arm for inputting a rotation angle to the angle sensor main body, the rotation interlocking arm, and the rotation interlocking arm. It has an angle transmission arm that is connected to the angle input arm and transmits the left-right rotation of the rotation interlocking arm to the angle input arm.
The work equipment steering device according to any one of claims 6 to 8, wherein the angle transmission arm is curved outward in a convex shape so as to avoid interference with the angle sensor main body and the drawbar following arm. A work machine comprising the work machine traction device according to any one of claims 1 to 5, or the work machine traction device and the work machine steering device according to any one of claims 6 to 9.

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