JPH0314970Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to the structure of a lower link in a three-point linkage mechanism.

(Prior Art) A forklift type elevating device is sometimes attached to the rear of a tractor via a three-point link mechanism consisting of a central top link and a pair of left and right lower links.

In this case, in order to improve the weight balance of the tractor and the lifting device as a whole and increase the lifting capacity of the lifting device, the lower link should be short in length, and the rear ends of both lower links should be Use a special type with narrow spacing between the connecting parts connected to the lifting device in the vehicle, so that part of the lifting device can be inserted between both rear wheels of the tractor, and the lifting device should be brought as close to the tractor as possible. I have to.

(Problem to be solved by the invention) However, when such a dedicated lower link is used, other work equipment, such as a frequently used rotary tiller, can be attached to the tractor instead of the lifting work equipment. When doing so, it is necessary to replace the above-mentioned dedicated lower link with a regular lower link that is longer than the above-mentioned dedicated lower link and has a wider gap between the joints at the rear ends of both lower links than the above-mentioned dedicated lower link. However, it was difficult to replace the lifting device with other work equipment, and it was not easy to replace the lifting device with other work equipment.

This invention is applicable to special working machines in which the distance between the left and right mounting parts connected to the lower link is narrower than that of normal working machines, and which is mounted closer to the tractor than normal working machines, and to normal working machines such as rotary tillers. Easy to replace the tractor with the work equipment 3
The purpose is to provide a structure of a lower link in a point link mechanism.

(Means for Solving the Problems) In order to achieve the above object, the present invention is characterized in that the lower link 13 is telescopically adjustable and its base end is pivoted to the tractor body 4. Expandable body 1
8, and an extension link 19 that is detachably provided as a front protrusion at the tip of the extensible body 18,
A connecting part 32 is provided at the distal end of the extendable body 18 to which the working machine 15 is connected when the extendable body 18 is in the contracted position and the extension link 19 is removed. The work machine 16 is in a state where the extensible body 18 provided with the
The distance between the connecting parts 40 and 74 of the extension link 19 is set according to the distance between the connecting parts 40 and 74 of the extension link 19.
The spacing is wider than the spacing between the connecting portions 32.

(Function) According to the present invention, the spacing between the left and right mounting parts connected to the lower link 13 is narrower than that of a normal working machine 16, and the special work is performed in which the mounting parts are mounted closer to the tractor 1 than a normal working machine 16. When attaching the machine 15 to the tractor 1, the extension link 19 is removed from the telescoping body 18, and the telescoping body 18 is placed in the contracted position.

Further, when the normal working machine 16 is mounted on the tractor 1, the extendable body 18 provided with the extension link 19 is placed in an extended position.

(Embodiment) An embodiment of the present invention will be described below based on the drawings of Figs. 1 to 4. 1 is an agricultural tractor that can be operated in both forward and backward directions. ing. The tractor 1 has a vehicle body 4 consisting of an engine, a transmission case 3, etc., and a seat and a steering device are movable between a forward driving position and a rearward driving position. Reference numeral 7 denotes a hydraulic system for lifting and lowering the working machine mounted on the rear part of the transmission case 3, and has a pair of left and right lift arms 8. Reference numeral 9 denotes a pair of left and right rear wheel cases, which protrude outward from both sides of the rear part of the transmission case 3. 5 is the rear wheel, 6
is the rear wheel fender.

Reference numeral 11 denotes a three-point link mechanism located at the rear of the tractor 1, which consists of a central top link 12 that can be freely adjusted by extension and contraction, and a pair of left and right lower links 13. 1
5 or a rotary tiller 16 is detachably attached to the tractor 1.

The lower link 13 has a telescopic body 18 that can be freely adjusted.
and an extension link 19 which is removably provided as a front-projecting shape on the distal end side of the extensible body 18.

The expandable body 18 includes a base link 20 and a tip link 21, and the base link 20 is swingably attached to and detached from a mounting pin 23 on the inner surface of the rear wheel case 9 via a ball joint 22 at its base end. It is equipped. A square tube body 24 is provided along the outer surface of the tip side of the base link 20, and the tip link 2 is attached to the square tube body 24.
1 is swingably inserted.

A bracket 25 that protrudes outward is fixed to the rectangular cylinder 24, and a fixing member is inserted into and removably through the rectangular cylinder 24, the tip link 21, and the base link 20. A pin 26 is inserted so as to be movable in the left and right direction. At the base end of the base link 20, a pin hole 27 for fixing during expansion is provided.
However, a pin hole 28 for fixing at the time of contraction is formed to pass through in the left and right direction in the approximately central portion in the longitudinal direction, and by inserting the fixing pin 26 into one of these pin holes 27 and 28, the expandable body 18 is fixed in the telescopic position shown in FIG. 3 and in the extended position shown in FIG.

The fixed pin 26 has a bullet receiving piece 2 at the center in the axial direction.
9 are fitted, and a holding pin 30 is inserted between the bullet receiving piece 29 of the fixing pin 26 and the rectangular cylinder body 24.

Reference numeral 31 denotes a bullet, which is wound around the fixed pin 26 between the outer surface of the bracket 25 and the bullet receiving piece 29, and biases the fixed pin 26 inward.

A cylindrical body 32 shown as a connecting portion is inserted into the distal end of the distal link 21 so as to penetrate in the left-right direction, and the cylindrical body 32 at the distal end of the distal link 21
There is a mounting pin hole 3 at a location slightly away from the base.
3 is formed through it.

The extension link 19 includes a base 34 disposed in the front-rear direction, a middle part 35 projecting outward from the tip of the base 34, a tip 36 projecting forward from the tip of the middle part 35, and the base 34. and a reinforcing rib 37 interposed between the intermediate portion 35 and the like.

The base 34 of the extension link 19 is provided with a pair of front and rear mounting pins 38 and 39 that protrude inwardly,
The extension link 19 is provided in the telescopic body 18 in a removable manner by inserting the front mounting pin 38 into the cylinder body 32 and the rear mounting pin 39 into the mounting pin hole 33 in a removable manner. .

The distal end portion 36 of the extension link 19 is provided with a ball joint 40 shown as a connecting portion, and both lower links 13
The spacing between the ball joints 40 is larger than the spacing between the cylindrical bodies 32. Both ends of a connecting shaft 41 are removably inserted into both ball joints 40, and both lower links 1
3, and a portion near the inner side of the ball joint 40 at both ends of the connecting shaft 41 is used as a mounting portion 42.

The lifting device 15 includes a pair of left and right fixed guide frames 43 arranged vertically, a pair of left and right movable guide frames 44 that are provided on each fixed guide frame 43 so as to be able to rise and fall freely, and a roller 45 that connects both movable guide frames 44 to each other. It is equipped with a lifting table 46 that can be raised and lowered freely, a pair of left and right L-shaped forks 47 that are provided on the lifting table 46 in a forward-protruding manner, and a lift cylinder 48 that raises and lowers the movable guide frame 44 and the lifting table 46. .

Both fixed guide frames 43 are integrally connected at the upper part by an upper connecting member 49, by a vertically intermediate connecting member 50, and at the lower part by lower upper and lower connecting members 51 and 52, respectively. An upper bracket 53 that projects forward is provided at the center in the left-right direction of the midway connecting member 50, and lower brackets 54 that project forward are provided at both sides of the lower upper and lower connecting members 51 and 52. The lower bracket 54 is provided with a mounting pin 55 that projects inward.

When the lifting device 15 is attached to the tractor 1 via the three-point link mechanism 11, the top link 12 is shortened compared to normal and connected to the upper bracket 53, as shown in FIGS. 2 and 3. At the same time, in the lower link 13, the extension link 19
With the telescopic body 18 in the contracted position, the cylindrical body 3 is removed.
2 is located forward of the rear end of the rear wheel 5, and the cylindrical body 32
By removably inserting the mounting pin 55 into the rear wheel 5, the lifting device 15 is mounted close to the tractor 1 with its rear end inserted between both rear wheels 5.

On the other hand, the rotary tiller 16 is provided with a pair of left and right brackets 57 that protrude forward, and a quick hitch 58 is provided at the tip of the brackets 57.

The quick hitch 58 includes a hit part 59 that is fixed to the tip of the bracket 57 and has a substantially U-shape in side view that opens forward, a cylindrical body 60 that is erected on the upper surface of the hit part 59, and a cylindrical body 60 and a hitch part 59. A retaining pin 61 is inserted into the portion 59 so as to be movable in the vertical direction.
, a bullet 62 provided in the cylinder body 60 and urging the retaining pin 61 downward; and a U-shaped gun 62 provided in the rear part of the hit part 59 so as to be movable in the front-rear direction and opening toward the front. A stopper 63, a cylindrical body 64 fixed to the rear surface of the hit portion 59 in a rearwardly projecting manner, and a cylindrical body 6
4 and the hit portion 59 so as to be movable in the front-rear direction, and a bullet 66 provided in the cylinder body 64 to urge the stopper 63 forward through the press pin 65. There is.

The retaining pin 61 is located at a detached position in which it has detached from the inside of the hit portion 59 as shown by the solid line in FIG.
As shown by the imaginary lines in the figure, the position can be freely changed between the retaining positions inserted into the upper and lower walls of the hit part 59.

When the rotary tilling device 16 is removed from the tractor 1, the stopper 63 has its upper surface in contact with the lower end of the retaining pin 61 to hold the retaining pin 61 in the detached position. The stopper 63 is a regulating piece 6 fixed to the inner surface of the hit portion 59.
7 and is restricted from moving forward.

When attaching the rotary tilling device 16 to the tractor 1, the top link 12 is extended, and as shown in FIG. A link 19 is provided, a ball joint 40 is located behind the rear end of the rear wheel 5, and both ball joints 40 are connected by a connecting shaft 41.

In this state, the tractor 1 is positioned in front of the tilling device 16, and the mounting portion 42 of the connecting shaft 41 is positioned in front of the hitch portion 59 of the quick hitch 58.

Next, the tractor 1 is moved backwards, and the tilling device 16 is
, and the mounting part 42 is fitted into the hit part 59, and the mounting part 42, which has been fitted into the hit part 59, pushes the stopper 63 toward the rear side.

When the mounting part 42 reaches the normal connection position shown by the imaginary line in FIG. 42 is prevented from coming off toward the front side of the hit portion 59.

Next, by connecting the top link 12 to the tilling device 16, the tilling device 16 can be mounted on the tractor 1.

Therefore, even when replacing the lifting device 15 and the tilling device 16, there is no need to attach or detach the lower link 13.
It is only necessary to extend and contract the extendable body 18 and to attach and detach the extension link 19, and replacement can be easily performed.

In the above embodiment, the mounting pin hole 33 into which the rear mounting pin 39 of the tip link 21 is inserted is
is not composed of a cylindrical body, but is simply a through hole,
Since there is no interference between the mounting pin hole 33 and the rectangular cylinder 24, the distance between the cylinder 32 and the rectangular cylinder 24 can be reduced when the telescopic body 18 is in the contracted position.

Note that the attachment pin hole 33 may be inserted into the rectangular tube body 24 when the expandable body 18 is in the contracted position.

FIG. 5 shows a second embodiment of the present invention, in which the square tube body 24 is not provided with the bracket 25, fixing pin 26, etc. of the first embodiment, and a tube protruding inwardly is provided at the tip of the base link 20. The body 69 includes a tip link 2.
The fixing pin 26, which is removably inserted into one of the fixing pin holes 27 and 28, is removably inserted into the cylindrical body 69 and the base link 20, thereby making the extendable body 18 freely adjustable.

FIG. 6 shows a third embodiment of the present invention, in which the tip link 21 of the extensible body 18 and the extension link 19
The following structure has been adopted as the mounting structure. That is, the rectangular cylinder 20 is provided along the outer surface of the midway part of the tip link 21 in the longitudinal direction, and the cylinder 32 that protrudes inward is fixed to the inner surface of the tip of the tip link 21. There is. Extension link 1
The base 34 of 9 is removably inserted into the rectangular cylinder 20, and a mounting pin 71 is removably inserted into the base 34, the tip link 21, and the cylinder 32.

FIG. 7 shows a fourth embodiment of the present invention, in which a mounting pin 7 is attached to the inner surface of the vehicle body 34 of the extension link 19.
A collar 72 into which 1 is inserted is fixedly provided. The thickness of the collar 72 is the same as the thickness of the side wall of the rectangular tube body 70, so that the extension link 19 can be fixed to the tip link 21 without rattling. In the extension link 19, a reinforcing rib 37 is interposed between the base portion 34 and the middle portion 35, and a reinforcing rib 73 is also interposed between the middle portion 35 and the tip portion 36. Further, the distal end portion 36 is provided with a mounting pin 74 projecting outward as a connecting portion, and a guiding disk 75 having an outwardly curved protrusion is rotatably fitted onto the base of the mounting pin 74. ing.

In addition, in the embodiment, a cylinder was used as the connection part of the tip link, but a ball joint may also be used.
Further, a cylinder may be used as the connecting portion of the extension link.

In addition, in the embodiment, an elevating work device was exemplified as a work machine in which the distance between the left and right attachment parts connected to the lower link is narrower than in a normal work machine, and the work machine is mounted closer to the tractor than in normal work. The above-mentioned work equipment also includes a spreader.

(Effects of the invention) As detailed above, according to the invention, the distance between the left and right mounting parts connected to the lower link is narrower than that of a normal working machine, and the mounting parts are mounted closer to the tractor than a normal working machine. It is easy to replace a special working machine with a normal working machine such as a rotary tiller on a tractor. The present invention has the above advantages and is of great practical benefit.

[Brief explanation of the drawing]

Figures 1 to 4 show a first embodiment of the present invention, with Figure 1 being a partial plan view of the tractor and rotary tiller, Figure 2 being a side view of the tractor and lifting device, and Figure 3 being a partial plan view of the tractor and rotary tilling device. The same plan view and FIG. 4 are partially sectional side views of the quick hitch, and each of FIGS. 5 to 7 is a plan view of a main part showing each of the second to fourth embodiments of the present invention. 1... Tractor, 11... Three-point linkage mechanism, 1
2... Top link, 13... Lower link, 15
...Elevating work device, 16...Rotary tillage device,
18...Extensible body, 19...Extension link, 32...
Cylindrical body, 40...Ball joint, 74...Mounting pin.

Claims (1)

[Scope of utility model registration request] One top link 1 in the center on the tractor body 4
2 and a pair of left and right lower links 13, in which working machines 15 and 16 are detachably attached.
The telescoping body is made up of a telescoping body 18 which is telescopically adjustable and whose base end is pivotally supported on the tractor body 4, and an extension link 19 which is removably provided as a front protrusion at the distal end of the telescoping body 18. At the tip of 18,
The telescopic body 18 is in the contracted position and the extension link 19
The work equipment 16 is provided with a connecting portion 32 to which the work equipment 15 is connected in a state in which the extension link 19 is removed, and a telescopic body 18 provided with the extension link 19 is in an extended position at the tip of the extension link 19. Connecting part 4 to be connected
0,74, and the connecting portion 40 of the extension link 19,
A structure of a lower link in a three-point link mechanism, characterized in that the distance between the points 74 and 74 is wider than the distance between the connecting portions 32 of the expandable body 18.