JPS6221473Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a power transmission device for a mid-mounted mower, which does not allow grass to become entangled, has sufficient ground clearance on the side that connects the tractor body, and is easy to maintain. Another object of the present invention is to provide a power transmission device with a simple structure.

Conventionally, in mid-mount mowers attached to the lower abdomen of the tractor body, power was transmitted to the mower from the front PTO shaft installed at the front end of the tractor body, or from the rear PTO shaft installed at the rear end of the tractor body. . However, in the former case, power is transmitted from the front PTO shaft located in front of the front axle to the input shaft of the mower via a universal joint shaft that extends rearward through the bottom of the front axle. Therefore, there is a problem that uncut grass tends to get wrapped around the power transmission device during mowing work, and there is also the inconvenience that the ground clearance of the connecting part of the power transmission device to the tractor body is too low. . In addition, in the latter case, power was transmitted from the rear PTO shaft to the input shaft of the mower via a wrap-around transmission mechanism using a belt, so the belt easily came off the pulley when the mower was raised and lowered, and maintenance The reality is that it took a lot of time and effort.

The present invention has solved the above problem, and its characteristics are that a mid-mount mower is installed below the tractor body so that it can be raised and lowered freely via a pair of left and right lifting link mechanisms, and the mower is mounted on the mower machine frame. , a plurality of cutters that are rotatably arranged in parallel on the lower side of the mower frame and whose rotation trajectories do not overlap with each other, a winding transmission mechanism that interlocks these cutters, and an input shaft that interlocks with the winding transmission mechanism. The winding transmission mechanism has a plurality of pulleys that interlock with each cutter, and a belt that interlocks these pulleys, and a mid-PTO shaft is provided on the tractor body behind the input shaft of the mower, and the PTO The shaft is removably connected to the input shaft via a joint shaft, and the joint shaft is located between the tractor body and the mower machine frame and between the left and right lifting link mechanisms.

Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments. FIGS. 1 to 4 show an agricultural tractor in which a rotary mid-mount mower 2 is attached to the lower abdomen of a body 1 of the agricultural tractor. The tractor body 1 consists of an engine, a transmission case 3, etc., and is provided with a hydraulic device 5 having a lift arm 4 at the rear thereof, and a seat 6 above the device 5. 7 is a bonnet that covers the engine etc., 8 is a front wheel, and 9 is a rear wheel. Reference numeral 10 denotes a pair of left and right stays, which extend outward from both sides of the tractor body 1 in the front and rear middle portions. On each side of the tractor body 1, a bending link mechanism 12 shown as a pair of left and right lifting link mechanisms is interposed between a pair of stays 10 and a mower frame 11.
The mower 2 is suspended from the tractor body 1 so as to be movable up and down. Then, the bending link mechanism 12 and the lift arm 4 are connected to the Bowden wire 13 and the link mechanism 4.
The mower 2 is raised and lowered by being connected via the mower 2.
The front end of the mower frame 11 is formed into an arrowhead shape, and a guide cover 15 for guiding grass clippings laterally is attached to one side, and an opening on the other side is closed by a lid 16. The upper surface of the rear side of the mower frame 11 is a horizontal plane that is one step lower than the front side, and a transmission box 18 is fixed to the center of the front part of the surface via a pair of left and right stays 17, and this box 18 is vertically The barrel 19 and the rear barrel 20 form a T-shape.
The lower end of the vertical cylindrical body 19 is located slightly above the upper surface of the mower frame 11, and the cutter shaft 2 is located inside the vertical cylinder body 19.
1 is rotatably provided and installed below. The lower side of the cutter shaft 21 is inserted through a bearing case 22 fixed to the mower frame 11, and a cutter 24 with a protective cover 23 is spline-coupled to the lower end thereof. The rotation loci of each cutter 24 do not overlap with each other. Further, cutter shafts 21 each having a cutter 24 with a protective cover 23 are provided on both sides of the mower frame 11, and a sheet metal transmission pulley 25 fixed to these cutter shafts 21 is connected to a belt with a tension pulley 26. 2
7, a winding transmission mechanism 28 is constructed, and the mechanism 28 is covered with a cover 29. The tension pulley 26 is provided on a swingable arm 30, and the arm 30 is supported by a spring 31.
It is being repulsed by. By the way, a driven pinion 32 is fixed to the upper end of the central cutter shaft 21 disposed in the vertical cylinder body 19, and a driving pinion 33 that meshes with the driven pinion 32 is fixed to the input shaft 34. The input shaft 34 is supported by the rear barrel 20 and projects rearward from the barrel 20, and the input shaft 34 has a mid-PTO shaft 35 located at the rear and upper side thereof, and has a universal joint 36 at both ends. Telescopic universal joint shaft 37
are interlocked and connected via. Mid PTO axis 3
5 is rotatably supported by the power take-off case 38 in a forward-protruding manner, and is fitted onto the transmission shaft 41 in the transmission case 3 via a gear 39 integrally formed with the mid-PTO shaft 35 and an intermediate gear 40. The transmission sliding gear 42 is engaged with the transmission sliding gear 42. The intermediate gear 40 is fitted around an intermediate shaft 43 fixed to a power take-off case 38 so as to be freely rotatable, and the power take-off case 38 is inserted into the transmission case 38 so as to close an opening 44 formed in the bottom wall of the mission case 3. It is fixed to the bottom wall of the case 3. Power is transmitted from the engine to the transmission shaft 41 via the transmission. By the way, in order to be able to adjust the cutting height of the cutter 24, a pair of caster-type front gauge wheels 45 are provided at the front positions of both ends of the mower frame 11, and a pair of left and right front gauge wheels 45 are provided at the rear position of the center part of the mower frame 11. A rear gauge wheel 46 is arranged. The front gauge wheel 45 is pivoted to the mower frame 11 via a parallel link mechanism 47 so as to be vertically movable, and each parallel link mechanism 47 is connected to the interlocking shaft 4.
8, and an upper link 49 extends rearward from one parallel link mechanism 47. The rear gauge wheel 46 is vertically movably supported by an interlocking shaft 50, and a rear link 51 extends forward from the interlocking shaft 50.
It is moved up and down by the operating lever 53 via the like, and the front and rear gauge wheels 45, 46 are thereby moved up and down. The operating lever 53 is pivoted to a guide plate 54 provided on the mower frame 11 so as to be swingable back and forth.
The operating lever 53 and the guide plate 54 are provided with means for positioning the operating lever 53 at each operating position. In order to prevent the mower frame 11 itself from directly touching the ground, a front grounding wheel 55 is provided at the front of the center of the mower frame 11, and rear gauge wheels are provided at the rear of both ends of the mower frame 11. 56 are deployed.

As detailed above, the present invention is equipped with a mid PTO shaft on the tractor body behind the input shaft of the mower.
Since the PTO shaft is interlocked and connected to the input shaft via the joint shaft, there is no risk of uncut grass interfering with and wrapping around the power transmission device, and the power Since the height of the transmission device is not restricted by the front axle or the like, sufficient ground clearance can be secured on the side where the tractor body is connected. In addition, since the input shaft and the mid-PTO shaft are connected via a joint shaft, there is no problem of the belt coming off the pulley when the mower is raised or lowered, which is the case with conventional methods, and maintenance can be easily performed. . Since the joint shaft is located between the tractor body and the mower and between the left and right lifting link mechanisms, there is less risk of the joint shaft coming into contact with obstacles and being damaged during reaping work, etc., and the joint shaft There is little risk of touching the surface with your hands, making it highly safe. tractor body
Even though the PTO shaft and the input shaft of the mower are connected via a joint shaft, each cutter of the mower is linked by a winding transmission mechanism, so the cutter may come into contact with an obstacle, causing excessive force on the cutter. Even when a load is applied, damage to the cutter and transmission system can be prevented by the slippage between the pulley and belt of the winding transmission mechanism.
The present invention has the above-mentioned various advantages, has a simple structure, can be implemented at low cost, has few failures, and is highly profitable.

[Brief explanation of the drawing]

Fig. 1 is a side view of a tractor with a mid-mount mower showing an embodiment of the present invention, Fig. 2 is a plan view thereof, Fig. 3 is a front view thereof, and Fig. 4 is an enlarged sectional view of the power transmission device. It is. 1... Tractor body, 2... Mid-mount mower, 11... Mower machine frame, 18... Transmission box,
24... Cutter, 34... Input shaft, 35... Mid PTO shaft, 37... Universal joint shaft, 38... Power take-off case.

Claims (1)

[Scope of Claim for Utility Model Registration] A mid-mounted mower is disposed below the tractor body so that it can be raised and lowered via a pair of left and right lifting link mechanisms, and the mower is rotatable between the mower machine frame and the lower side of the mower machine frame. It has a plurality of cutters arranged in parallel and whose rotation loci do not overlap with each other, a winding transmission mechanism that interlocks these cutters, and an input shaft that interlocks with the winding transmission mechanism. In a tractor that has multiple pulleys that interlock with each other and a belt that interlocks these pulleys, the
A PTO shaft is provided, the PTO shaft is detachably connected to the input shaft via a joint shaft, and the joint shaft is located between the tractor body and the mower machine frame and between the left and right lifting link mechanisms. Power transmission device to Midmount mower.