JPH10127102A - Mission device for farm work machine and farm work machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mission device for a farm work machine capable of circulating lubricating oil inside a gear pump when an input shaft is reversely rotated and preventing the danger that the gear pump is damaged by frictional heat or the like and the farm work machine provided with the mission device. SOLUTION: This mission device 3 is provided with a mission case 13 filled with the lubricating oil 12, the freely normally and reversely rotatable input shaft 15 provided with a bevel gear 17, an output shaft 19 provided with a linked bevel gear 21 engaged and linked with the bevel gear 17 of the input shaft 15 and the gear pump 26 for sucking the lubricating oil 12, ejecting it inside the mission case 13 and circulating it at the time of the normal rotation of the input shaft 15 and sucking the lubricating oil 12 from an ejection side and circulating it inside at the time of the reverse rotation of the input shaft 15. The gear pump 26 is provided with a driving gear, a driven gear, a circulation path provided with a suction port provided with a filter 38 and an ejection port for circulating the lubricating oil 12 at the time of the reverse rotation of the input shaft 15 and a circulation path opening/closing means for closing the circulation path at the time of the normal rotation of the input shaft 15 and opening the circulation path at the time of the reverse rotation of the input shaft 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mission device for an agricultural work machine and an agricultural work machine, and more particularly to a mission device for outputting to a work body such as a tilling work machine and a scraping work machine, and an agricultural work machine provided with the mission device.

[0002]

2. Description of the Related Art Conventionally, this kind of agricultural working machine is provided with a mission device. As this mission device,
For example, a transmission case, an input shaft rotatably provided in the transmission case, a bevel gear fixed to the input shaft, an output shaft rotatably provided in the transmission case, and a transmission shaft fixed to the output shaft. And a gear pump having two gears meshed with each other to circulate the lubricating oil in the transmission case. The input shaft is connected via a power transmission shaft to a PTO shaft of a tractor that pulls the agricultural work machine.

[0003]

In the transmission device, when the PTO shaft of the tractor rotates only in one direction (forward rotation), the input shaft is rotated forward by the PTO shaft and the gear pump is rotated. Is operated, and the lubricating oil in the transmission case is circulated by this gear pump, so that bevel gears and interlocking bevel gears meshing with each other are prevented from being damaged by heat or the like, but the input shaft is reversed. In such a case, the gear pump may run out of oil during the suction of lubricating oil, and lubricating oil may not be sucked into the gear pump, and the gear pump may be damaged due to frictional heat generated by the reverse rotation of the two gears meshed with each other There is.

Further, the conventional tractor PTO shaft is of a type that rotates only in one direction (forward rotation). Recently, however, the tractor PTO shaft has been adapted to be compatible with the working method of agricultural work machines.
Since the shaft is of a type that can be switched between forward rotation and reverse rotation, the tractor PT
When the input shaft is rotated by the O-axis and the input shaft is reversed by erroneously operating the rotation direction of the PTO shaft, there is a risk that the lubricating oil is interrupted and the gear pump is damaged.

[0005] Further, in the agricultural work, for example, in the work of leveling the convex portions of the headland or the like, the input shaft is switched from the normal rotation to the reverse rotation by the PTO shaft, and the convex portions of the headland or the like are leveled while moving backward. Then, after leveling the ground, the ship moves forward again to perform the work. At this time, it is often forgotten to switch the input shaft from the reverse rotation to the normal rotation with the PTO shaft, and the forward work is performed with the reverse rotation. There is a danger that the lubricating oil will be interrupted and the gear pump will be damaged.

[0006] The present invention has been made in view of such a point, the lubricating oil can be circulated in the gear pump even when the input shaft is reversed, and the lubricating oil is interrupted in the gear pump. It is an object of the present invention to provide a mission device for an agricultural work machine that can prevent the risk of the gear pump being damaged by frictional heat or the like without any problem, and an agricultural work machine equipped with the mission device.

[0007]

According to a first aspect of the present invention, there is provided a mission device for an agricultural work machine, comprising: a transmission case filled with lubricating oil; and an input shaft rotatably provided in the transmission case and having a bevel gear and capable of rotating forward and reverse. An output shaft rotatably provided on the transmission case and having an interlocking bevel gear meshed with and interlocked with the bevel gear of the input shaft; and an output shaft that is driven to rotate by an output from the input shaft and rotates when the input shaft rotates forward. A reversible pump for sucking lubricating oil, discharging and circulating the lubricating oil into the transmission case, and recirculating the lubricating oil from the discharge side and circulating the lubricating oil internally when the input shaft rotates in the reverse direction.

When the input shaft is rotated forward, lubricating oil in the transmission case is sucked into the reversible pump by a reversible pump that is rotationally driven by the output from the input shaft, and the transmission case is discharged from the discharge port of the reversible pump. Therefore, the lubricating oil is circulated between the transmission case and the reversible pump by the reversible pump, and the lubricating oil sufficiently lubricates the bevel gear and the interlocking bevel gear in the transmission case and the reversible pump. The gears are rotated in this state, and these gears are prevented from being damaged or broken due to frictional heat or the like.

When the input shaft rotates in reverse, lubricating oil is sucked from the discharge side by a reversible pump driven in reverse by the output from the input shaft and circulated inside the reversible pump. Therefore, the inside of the reversible pump is rotated in a sufficiently lubricated state by this lubricating oil, and the reversible pump is prevented from being damaged or broken by frictional heat or the like.

According to a second aspect of the present invention, the reversible pump is a gear pump provided in a transmission case. When the input shaft rotates forward, lubrication oil is circulated between the transmission case and the gear pump by the gear pump, and when the input shaft rotates reversely, lubrication oil is circulated in the gear pump by the gear pump, Therefore, even when the input shaft rotates in any direction, the bevel gear and the interlocking bevel gear in the transmission case and the gear in the gear pump are prevented from being damaged or broken due to frictional heat or the like.

According to a third aspect of the present invention, there is provided the mission device for an agricultural work machine according to the first or second aspect, wherein the gear pump includes a drive gear rotatably driven by an output from the input shaft and the drive gear. A meshed driven gear, a suction port having a filter opened in the transmission case on one side, and a discharge port opened in the transmission case on the other side. And a circulation path opening / closing means which is provided in the circulation path so as to be able to move forward and backward, and which closes the circulation path when the input shaft rotates forward and opens the circulation path when the input shaft rotates reversely.

During normal rotation of the input shaft, lubricating oil in the transmission case is sucked from the suction port of the gear pump via the filter by the drive gear and the driven gear, and is closed by the circulation path opening / closing means. The fluid flows between the drive gear and the driven gear via the path and is discharged from the discharge port of the gear pump into the transmission case. That is, when the drive gear and the driven gear are driven to rotate by the input shaft, the lubricating oil is sucked from the suction port on the low pressure side and discharged into the transmission case from the discharge port on the high pressure side.

When the input shaft rotates in reverse, lubricating oil is sucked from the discharge side by the driving gear and the driven gear driven in reverse and flows into the circulation path, and the lubricating oil and the lubricating oil in the gear pump are used. The circulation path opening / closing means is pushed, the circulation path is opened by the circulation path opening / closing means, and the lubricating oil is circulated through the circulation path.

At this time, the lubricating oil tends to be discharged from the filter at the suction port into the transmission case. However, the viscosity of the lubricating oil and the filter make it difficult for the lubricating oil to be discharged from the suction port into the transmission case. Therefore, the lubricating oil is circulated through the circulation path.

That is, when the drive gear and the driven gear are driven to rotate by the input shaft, the lubricating oil is sucked from the discharge side of the input shaft on the low pressure side during the forward rotation, and is lubricated at the time of the forward rotation on the high pressure side. Although the lubricating oil is about to be discharged to the suction side, the lubricating oil is circulated through the circulation path because the lubricating oil is hardly discharged from the suction port into the transmission case by the viscosity of the lubricating oil and the filter. Therefore, no oil shortage occurs in the gear pump, and the drive gear and the driven gear in the gear pump are rotated by this lubricating oil in a sufficiently lubricated state.

According to a fourth aspect of the present invention, there is provided the mission device for an agricultural work machine according to the third aspect, wherein the circulation path opening / closing means communicates with a valve seat provided on the circulation path and the circulation path. A plunger chamber, a plunger housed in the plunger chamber so as to be able to advance and retreat, and a plurality of communication holes communicating with the circulation path and the valve seat, and biasing the plunger to constantly join the valve to the valve seat. And a spring for closing the circulation path.

During forward rotation of the input shaft, the lubricating oil sucked by the driving gear and the driven gear flows into the circulation path, and the lubrication oil flows out of the communication hole of the plunger into the plunger chamber communicating with the circulation path. Is done. Further, when the plunger chamber is filled with the lubricating oil, the plunger is further pushed by the lubricating oil and the spring, the valve of the plunger is joined to the valve seat, and the circulation path is reliably closed. Therefore, the lubricating oil flows between the drive gear and the driven gear without being circulated through the circulation path, and is discharged from the discharge port of the gear pump into the transmission case.

Further, when the input shaft rotates in the reverse direction, lubricating oil is sucked from the discharge side of the input shaft during normal rotation and flows into the circulation path by the driving gear and the driven gear driven in the reverse direction. The plunger valve is pushed back against the spring by the lubricating oil therein, and is retracted. When the valve seat is opened by the valve, the lubricating oil is circulated through the circulation path.

At this time, the lubricating oil tries to be discharged from the filter at the suction port into the transmission case. However, the viscosity of the lubricating oil and the filter make it difficult for the lubricating oil to be discharged from the suction port into the transmission case. Therefore, the lubricating oil is concentrated on the plunger valve, and the plunger valve is reliably pushed back against the spring by the lubricating oil, and the plunger valve is opened apart from the valve seat. It is circulated in the circuit.

According to a fifth aspect of the present invention, there is provided an agricultural work machine having a three-point connecting portion connected to a tractor, and an input shaft provided on the machine frame protruding so as to be connectable to a power take-off shaft of the tractor. 5. A mission device according to claim 4, and a rotary work body for ground work, which is rotatably provided on the machine frame and is rotationally driven by an output from an output shaft of the mission device.

In a farming operation in which the three-point connecting portion of the machine frame is connected to the three-point connecting portion of the tractor and the input shaft of the transmission device is connected to the PTO shaft of the tractor, for example, the projecting portion is leveled by a headland or the like. At the time of operation, the input shaft is switched from forward rotation to reverse rotation by the PTO shaft and the rotary work body is rotationally driven by the output from the output shaft of the transmission device while moving backward, so that the headland or the like is Is leveled evenly.

Then, we move forward again and work,
At this time, without forgetting to switch the input shaft from the reverse rotation to the normal rotation with the PTO shaft, the lubricating oil is circulated in the gear pump even when the rotary work body performs the forward work with the reverse rotation. Further, the lubricating oil is not interrupted and the gear pump is not damaged.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

Reference numeral 1 denotes an agricultural working machine.
The machine frame 2 has a left-right hollow pipe-shaped main frame 4 to which a transmission device 3 is fixed at an intermediate portion, and projects forward and downward parallel to both sides of the main frame 4. Left and right lower connecting arms 6 each having a lower pin 5 as a connecting portion protruding at a front end thereof, and an upper connecting arm 6 protruding forward and upward above the transmission device 3 and having a connecting hole 7 as a connecting portion at the front end thereof. 8 is provided. The three-point connecting portion including the lower pin 5 and the connecting hole 7 on both sides is connected to the three-point connecting portion of the tractor.

The machine frame 2 is composed of upper and lower pivot plates 9 projecting in parallel from both sides of the main frame 4 toward the rear and upward, respectively, and upper and lower pivot plates 9 on both sides. And a vertical rotation center shaft 10 which is inclined forward and downward with respect to the vertical axis, and which is supported so that it can be inserted and removed, and located inside the upper and lower supporting plates 9 on both sides. In addition, a support arm 11 is integrally provided on both sides of the main frame 4 to protrude rearward and upward.

Next, the transmission device 3 has a transmission case 13 fixed to an intermediate portion of the main frame 4 and filled with a lubricating oil 12. The input shaft 15 in the front-rear direction is rotatably supported in the forward and reverse directions, and a spline shaft portion 16 formed at the front of the input shaft 15 projects toward the front of the transmission case 13. A bevel gear 17 is provided at the rear end.

Further, a spur gear 18 is integrally fixed to the input shaft 15 by spline fitting at a position between the bearing members 14 at the front and rear of the transmission case 13. The spline shaft portion 16 of the input shaft 15 is linked to the PTO shaft of the tractor via a power transmission shaft.

A left-right output shaft 19 is rotatably inserted into the transmission case 13 and the left-right main frame 4 at a position behind the bevel gear 17 of the input shaft 15.
Both ends of the output shaft 19 are rotatably supported by bearings 20 provided in both ends of the main frame 4. Further, an interlocking bevel gear 21 which is located in the transmission case 13 and meshes with the bevel gear 17 of the input shaft 15 is rotatably mounted on the output shaft 19.

The interlocking bevel gear 21 is connected to and released from the output shaft 19 by a pawl clutch 22 which is spline-fitted to the output shaft 19 and is axially movable back and forth only in the axial direction. It has become so. Further, the transmission case 13 is provided with a clutch switching means 23, and the clutch switching means 23 has an interlocking body 24 which interlocks the claw clutch 22 in the axial direction.

Next, a reversible pump 25 is fixed in the transmission case 13. The reversible pump 25 includes a gear pump 26. The gear pump 26 has a pump body 27. The pump body 27 includes a housing 28 and a frame 29 detachably attached to a front end of the housing 28.

The housing 28 has a pump chamber 30 having an opening on the frame 29 side. The pump chamber 30 has arc-shaped guide recesses 31 for guiding the rotation of the gears relative to the upper and lower portions. Each has a flow recess 32 through which the lubricating oil 12 flows. The housing 28 has a communication hole 33 on the rear side thereof communicating with the rear ends of the left and right circulation recesses 32, respectively, and circulates the lubricating oil 12 through the communication hole 33 and the left and right circulation recesses 32. Circulation circuit
34 are formed.

The housing 28 has, on one side, a suction passage 35 communicating with the rear side of the one-side flow recess 32.
The suction port 36 of the suction passage 35 is opened on one side surface of the housing 28. The lubricating oil 12 of the transmission case 13 is connected to the suction port 36 via a suction pipe 37 connected in a liquid-tight manner.
A filter 38 inserted therein is mounted. Further, the housing 28 has front and rear bearing holes 41 and 42 in which metals 40 are provided above and below a rear side wall 39 of the pump chamber 30, respectively.

The frame 29 has a bearing hole 45 penetrating in the front-rear direction provided with a metal 43 and an oil seal 44 facing the bearing hole 41 in the upper part of the housing 28 and a bearing hole 42 in the lower part of the housing 28. , Each of which has a bearing hole 47 in the front-rear direction provided with a metal 46.

The frame 29 is formed on the other end between the upper bearing hole 45 and the lower bearing hole 47, and is formed at the front end of the flow recess 32 on the other side of the housing 28. A discharge port 48 formed at an outer end of the discharge path 48 of the discharge path 48 and communicating with the oil reservoir 32a. Have been. One end of a conduit 50 is connected to the discharge port 49 in a liquid-tight manner, and a discharge port 51 opened at the other end of the conduit 50 faces the lubricating oil 12 in the transmission case 13. It is arranged.

Next, the bearing hole 45 in the upper part of the frame 29
A drive shaft 52 in the front-rear direction is rotatably mounted on a bearing hole 41 at an upper portion of the housing 28 via respective metals 40 and 43 and an oil seal 44. A drive gear 53 that is positioned at the upper portion and rotated is integrally formed. Each tooth of the drive gear 53 is adapted to be closely rotated along the arcuate guide recess 31 in the upper part of the pump chamber 30.

A driven shaft 54 in the front-rear direction is rotatably mounted in a bearing hole 47 at a lower portion of the frame 29 and a bearing hole 42 at a lower portion of the housing 28 via respective metals 40 and 46. A driven gear 55, which is located at a lower part in the pump chamber 30 and meshes with the drive gear 53, is formed integrally with the shaft 54. The driven gear 55 is connected to the drive gear 53.
, And each tooth of the driven gear 55 is rotated close to the lower part of the pump chamber 30 along the arcuate guide recess 31.

The drive shaft 52 has a spline shaft portion 56 projecting forward from the frame 29. The spline shaft portion 56 is mounted on a bearing body 57 provided before and after the front portion of the transmission case 13. A spur gear 58 meshed with the spur gear 18 of the input shaft 15 is spline-fitted to the spline shaft portion 56.

The drive shaft 52 is rotated by the output from the input shaft 15 via the spur gears 18 and 58. When the input shaft 15 rotates forward, the drive gear 53 and the drive gear 53 are rotated. The lubricating oil 12 in the transmission case 13 passes through the filter 38 through the driven gear 55 meshed with
It is sucked into the pump chamber 30 from the outlet 36 and is discharged into the transmission case 13 from the discharge passage 48 and the discharge port 51 of the conduit 50.When the input shaft 15 rotates in the reverse direction, the drive gear 53 and the driven gear 55 The lubricating oil 12 in 50 is sucked into the pump chamber 30 and circulated in the circulation path 34.

Next, in the circulation path 34 of the housing 28, circulation path opening / closing means 59 for closing the circulation path 34 when the input shaft 15 rotates forward and opening the circulation path 34 when the input shaft 15 rotates reversely. Is provided.

The circulation path opening / closing means 59 is provided with an annular valve seat 60 which is fitted in one end of the communication hole 33 of the circulation path 34 in a liquid-tight manner, and communicates with one end of the communication hole 33 in the housing. The plunger chamber 61 formed in 28 and this plunger chamber
A hollow plunger 64 having a valve 62 which is housed so as to be able to advance and retreat to the valve seat 60 at its distal end and which can be freely connected to and separated from the valve seat 60, and a plurality of communication holes 63 communicating with the communication holes 33 of the circulation path 34; and the plunger chamber 61 Plug 65 screwed to the outer end of the
And a coil spring 66 provided between the plug 65 and the plunger 64 to urge the plunger 64 to constantly join the valve 62 to the valve seat 60 to close the circulation path 34. .

When the input shaft 15 is rotated forward, the lubricating oil 12 sucked by the driving gear 53 and the driven gear 55 flows into the plunger chamber 61 from the communication recess 32 on the other side and the plurality of communication holes 63 of the plunger 64. When the plunger 64 flows and fills the plunger chamber 61, the plunger 64 is relatively strongly pushed by the lubricating oil 12 and the coil spring 66, and the valve 62 of the plunger 64 comes into close contact with the valve seat 60 and the communication hole 33. Is closed, so that the lubricating oil 12 is discharged from the discharge path 48.

When the input shaft 15 rotates in the reverse direction, the driving gear
The lubricating oil 12 sucked from the discharge side by the 53 and the driven gear 55 tries to be discharged from the suction passage 35 and the filter 38 into the transmission case 13.
The lubricating oil 12 is hardly discharged into the transmission case 13 due to the resistance of the lubricating oil 12. The valve 62 of the plunger 64 is pushed against the coil spring 66, and the valve 62 is separated from the valve seat 60 to open the communication hole 33. Therefore, the lubricating oil 12 circulates in the circulation path 34. It is supposed to be.

At the rear end of the housing 28, an oil drain hole 67 is formed which communicates with the rear end of the one-side flow recess 32. A plug 68 is liquid-tightly connected to the oil drain hole 67. It is attached detachably. Further, the housing 28 and the frame 29
Are positioned by a plurality of positioning pins 69, and an O-ring 70 is provided on the joint surface between the housing 28 and the frame 29.
The drive shaft 52 and the driven shaft 54 are located between the housing 28 and the frame 29 and the bearing plate
It is rotatably supported at 71. The housing 28 and the frame 29 are integrally and liquid-tightly fastened and fixed by a plurality of bolts 72.

Next, the rotation center axes on both sides of the main frame 4
The left and right working machines 73 are attached to 10 so as to be rotatable, that is, to be foldable around the rotation center shafts 10 on the both side portions. When working, the left and right working machines 73 are arranged at both ends of the main frame 4 to form a series of ground working bodies. Are folded and arranged side by side in parallel with each other.

The left and right working machines 73 are mounted on the rotation center shaft 10.
A right-and-left hollow pipe-shaped connecting frame 74 rotatably supported by a bracket, a bracket 75 attached to the inner end of the connecting frame 74, and an outer side of the connecting frame 74 facing the bracket 75. Transmission case mounted at the end
76, and a rotary work body 77 for ground work rotatably mounted between the lower ends of the bracket 75 and the transmission case 76 on both sides.

A rotary shaft 78 which is rotated by an output from the output shaft 19 of the transmission device 3 is rotatably provided in the connecting frame 74, and an inner end of the rotary shaft 78 and the output shaft 19 are provided. The outer end of the rotary shaft 78 protrudes into the transmission case 76.

The rotary working body 77 is provided with a tilling shaft 80 rotatably mounted between lower ends of the bracket 75 and the transmission case 76, and a radially spaced radially spaced apart from the tilling shaft 80. It has a large number of projecting tilling claws 81.
Further, the outer end of the tilling shaft 80 projects into the transmission case 76, and the outer end of the tilling shaft 80 is provided at the outer end of the rotary shaft 78 in the interlocking medium 82 provided in the transmission case 76. And are rotatably linked.

Further, a cover 83 covering the upper part of the rotary working body 77 is integrally fixed between the bracket 75 and the transmission case 76, and a rubber plate 84 is attached to the rear end of the cover 83. A first terrain body 85 is attached to the rear surface of the first terrain body 85 via a left-right support shaft 86.
Is fixed to be vertically rotatable. Further, the first terrain body 85 is suspended by a first suspension body 88 protruding from the cover body 83, and the second terrain body 87 is protruded from the connection frame 74 by the second suspension body 88. Suspension
At 89, it is suspended so as to be able to freely rotate vertically.

Further, between the left and right support arms 11 projecting from the rear portions on both sides of the main frame 4 and the connecting frames 74 of the left and right working machines 73, each working machine 73 is in a working state and a non-working state. Hydraulic cylinder device 90 that rotates and supports the state
Are attached. Although not shown, a lock means is provided for locking the left and right working machines 73 to the machine frame 2 when the left and right working machines 73 are deployed in a working state.

Next, the operation of the above embodiment will be described.

During the operation, the left and right hydraulic cylinder devices 90 are operated to extend the piston rods, so that the left and right working machines 73 are respectively rotated forward about the rotation center axis 10, and the left and right working machines 73 are rotated. The inner end of the connecting frame 74 of the machine 73 is opposed to both ends of the main frame 4, and both ends of the output shaft 19 in the main frame 4 are connected to the rotating shafts 78 in the connecting frame 74 of the left and right working machines 73. Are connected by a pawl clutch 79, respectively.

The left and right working machines 73 are deployed at both ends of the main frame 4 in a working state, and the left and right working machines 73 are locked to the machine frame 2 by respective locking means. The working machine 73 is held in a deployed state, and the rotary working bodies 77 of the left and right working machines 73 constitute a series of ground working bodies.

Next, the three-point connection portions 5 and 7 of the agricultural work machine 1 are connected to the three-point connection portion of the suspension mechanism of the tractor, and the input shaft 15 of the transmission device 3 is connected to the PTO shaft of the tractor via a power transmission shaft. The spline shaft portions 16 are spline-fitted and connected.

Then, the agricultural machine 1 is towed forward by the tractor, and the input shaft 15 of the transmission 3 is rotated in the forward direction by the PTO shaft of the tractor via the power transmission shaft. Occasionally, the output shaft 19 is rotated by the bevel gear 17 of the input shaft 15 via the interlocking bevel gear 21 and the pawl clutch 22, and the pawl clutches are provided at both ends of the output shaft 19.
The rotating shafts 78 of the left and right working bodies 73 connected at 79 are rotated in conjunction with each other.

When the rotating shafts 78 of the left and right working bodies 73 are respectively rotated, the rotary working bodies 77 of the left and right working bodies 73 are respectively down-cut by the left and right rotating shafts 78 via the interlocking medium 82. The field is driven while being plowed sequentially from a work start position such as a headland by the respective tilling claws 81 of the left and right rotary working bodies 77.

When the input shaft 15 rotates forward, the input shaft
At 15, the drive shaft 52 of the gear pump 26 is rotationally driven via the spur gears 18 and 58, and the driven gear 55 of the driven shaft 54 is interlocked and rotated by the drive gear 53 of the drive shaft 52.
The lubricating oil 12 in the transmission case 13 is
Is sucked into the suction passage 35 from the suction port 36 of the gear pump 26 via the filter 38, and is discharged from the pump chamber 30 to the discharge path 48.The lubricating oil 12 further flows from the discharge port 51 of the conduit 50 to the transmission case 13 It is discharged into.

That is, when the drive gear 53 and the driven gear 55 are driven to rotate by the input shaft 15, the lubricating oil 12 is sucked from the suction port 36 on the low pressure side and discharged on the high pressure side.
It is discharged into the transmission case 13 from the discharge port 48 and the discharge port 51 of the conduit 50.

At this time, the lubricating oil 12 sucked by the driving gear 53 and the driven gear 55 flows into the flow recess 32 on the other side of the circulation path 34, and the lubricating oil 12 is supplied to the plurality of communication holes of the plunger 64. From 63, it flows out to the plunger chamber 61 communicating with the circulation path. When the plunger chamber 61 is filled with the lubricating oil 12, the lubricating oil 12 and the coil spring
The plunger 64 is further pushed by 66, and this plunger 64
The valve 62 is joined to the valve seat 60, and the valve 62
, The communication hole 33 is reliably closed, and the circulation path 34 is shut off.

Therefore, the lubricating oil 12 is not circulated through the circulation path 34 and is driven by the driving gear 53 and the driven
It is discharged from the inside to the discharge path 48 and discharged from the discharge port 51 of the conduit 50 into the transmission case 13.

Then, in this way, the lubricating oil 12 in the transmission case 13 is
The lubricating oil is circulated between
Bevel gear 17 and interlocking bevel gear in transmission case 13 at 12
21 and the drive gear 53 and the driven gear 55 in the gear pump 26 are rotated in a sufficiently lubricated state, and these gears 17, 21, 5
3, 55 is prevented from being damaged or broken by frictional heat or the like.

Next, at the work start position of the headland, the rotary work bodies 77 of the left and right work bodies 73 are respectively driven to rotate in the downcut direction, so that the tilled soil is rearwardly moved by the left and right rotary work bodies 77. The uncultivated land behind the work start position is raised with this tilling soil, and the lands are raised. You need to level the part.

Further, in some fields, it is necessary to level the ground evenly, in the process of tilling work in the field, when the cultivated soil has a convex portion that partially rises, In the case where there is a convex portion in which the cultivated soil swells, the convex portion and the like may be leveled evenly.

Therefore, the agricultural machine 1 is retracted by the tractor and stopped at a predetermined position, and the rotation direction of the PTO shaft of the tractor is switched from normal rotation to reverse rotation. Then, the agricultural machine 1 is towed again by the tractor, and the input shaft 15 of the transmission 3 is rotated in the reverse direction by the PTO shaft of the tractor via the power transmission shaft.
The output shaft 19 is reversed by the bevel gear 17 of the input shaft 15 via the interlocking bevel gear 21 and the pawl clutch 22, and the left and right working bodies connected to both ends of the output shaft 19 by the pawl clutch 79. The 73 rotation shafts 78 are respectively rotated in conjunction with each other.

When the rotating shafts 78 of the left and right working bodies 73 are reversed, the rotary working bodies 77 of the left and right working bodies 73 are respectively up-cut by the left and right rotating shafts 78 via the interlocking medium 82. It is driven to rotate in the direction, and with each tilling claw 81 of the left and right rotary work bodies 77, it is possible to proceed while leveling a convex portion rising on a non-tilled ground behind a work start position such as a headland. it can.

After the projecting portions of the uncultivated ground behind the headland or other work starting position are leveled evenly with the tillage claws 81 of the left and right rotary work bodies 77, the rotation direction of the PTO shaft of the tractor is changed. The tilling work is continued by switching from the reverse rotation to the forward rotation, but forgetting to switch the rotation direction of the PTO shaft of the tractor, and the rotary working bodies of the left and right working bodies 73 are forgotten.
There is a possibility that the tillage work will be continued with the 77s being driven to rotate in the upcut direction.

That is, even if the rotary working bodies 77 of the left and right working bodies 73 are respectively driven to rotate in the up-cut direction, the resistance of the soil to the tilling claws 81 of the left and right rotary working bodies 77 is small. It may not be noticed that the bodies 77 are still being driven to rotate in the upcut direction. In such a case,
The lubricating oil 12 is not circulated between the gear pump 26 and the transmission case 13 by the gear pump 26.

However, when the input shaft 15 is rotated in the reverse direction, the gear pump is driven by the input shaft 15 via the spur gears 18 and 58.
The drive shaft 52 of the 26 is driven in reverse rotation, and the drive shaft 52
The driven gear 55 of the driven shaft 54 is driven in reverse rotation by the driving gear 53, and the lubricating oil 12 is discharged by the driving gear 53 and the driven gear 55 when the input shaft is rotated forward, that is, the conduit 50, the discharge path 48, and the oil. The lubricating oil 12 in the reservoir portion 32a is sucked and flows into the circulation recess 32 on one side of the circulation path 34, and the valve 62 of the plunger 64 is coiled by the lubricating oil 12 and the lubricating oil 12 in the pump chamber 30. The lubricating oil 12 is circulated through the circulation path 34 when the valve 62 is separated from the valve seat 60 and the communication hole 33 is opened by being pushed and retracted against the spring 66.

At this time, the drive gear 53 and the driven gear 55 are driven to rotate in the reverse direction by the input shaft 15, so that the lubricating oil 12 is sucked from the discharge side of the input shaft 15 on the low pressure side when the input shaft 15 rotates forward, and When the lubricating oil 12 tries to discharge from the filter 38 of the suction port 36 into the transmission case 13, the lubricating oil 12
The lubricating oil 12 is suctioned by the viscosity of 12 and the resistance of the filter 38.
It is difficult to discharge the lubricating oil 12 into the transmission case 32 and the communication recess
From 33, the valve 62 of the plunger 64 is concentrated against the valve 62 of the plunger 64, and the valve 62 of the plunger 64 is reliably pushed back by the lubricating oil 12 against the coil spring 66. Is done.

Therefore, the lubricating oil 12 sucked from the discharge side of the input shaft 15 during normal rotation by the driving gear 53 and the driven gear 55 is circulated through the circulation path 34, and the lubricating oil 12 There is no danger that the drive gear 53 and the driven gear 55 in the gear pump 26 are rotated by the lubricating oil 12 with sufficient lubrication, and the gear pump 26 is damaged or damaged due to generation of heat. Is prevented.

By switching the rotation direction of the PTO shaft of the tractor from the reverse rotation to the forward rotation, the input shaft 15 is driven to rotate forward by the PTO shaft via the power transmission shaft. The rotary working bodies 77 are each driven to rotate in the downcut direction, and the tillage work is continued by the left and right rotary working bodies 77.

Next, in the above embodiment, the reversible pump
Mission device 3 with built-in 25 is mounted on the tillage machine,
The case where the tilling work machine is connected to a tractor capable of switching the PTO shaft between forward and reverse rotations to perform the tilling work has been described. However, the present invention is not limited to this, and the transmission device 3 having the built-in reversible pump 25 is a substitute working machine. The scraping machine may be mounted and connected to a tractor capable of switching the PTO shaft between forward and reverse rotations to perform the scraping task. Further, the mission device 3 with the built-in reversible pump 25 is another agricultural machine. And perform predetermined agricultural work.

If necessary, a check valve, a switching valve, a branching device, and the like may be interposed in the conduit 50 so that the lubricating oil
It is preferable to use 12 as a drive source to drive other devices.

[0073]

According to the first aspect of the present invention, the input shaft is driven to rotate by the output from the input shaft, and when the input shaft rotates forward, the lubricating oil in the transmission case is sucked, discharged into the transmission case and circulated. During the reverse rotation, a reversible pump was provided that sucks the lubricating oil from the discharge side and circulates it internally.
The lubricating oil circulated when the input shaft rotates forward can reliably protect each gear in the transmission case and the pump mechanism in the reversible pump from frictional heat, etc. The lubricating oil is not interrupted in the reversible pump and the risk of breakage or damage of the reversible pump due to frictional heat can be reliably prevented,
To provide a mission device for an agricultural work machine that can be used for a long time as a device capable of coping with an erroneous operation of switching between forward and reverse rotations, and thus can sufficiently cope with a tractor having a PTO shaft of a type capable of switching between forward and reverse rotations. Can be.

According to the invention of claim 2, in addition to the effect of the invention of claim 1, since the reversible pump is constituted by a gear pump provided in the transmission case, the lubricating oil circulates in the gear pump when the input shaft rotates in the reverse direction. The lubricating oil can reliably prevent the gear mechanism in the gear pump from being damaged or damaged due to frictional heat, etc., and the overall configuration by providing the gear pump in the transmission case However, the appearance can be improved easily.

According to the third aspect of the present invention, in addition to the effects of the first or second aspect, the gear pump further comprises a driving gear rotatably driven by an output from the input shaft and a driven gear meshed with the driving gear. A circulation path for circulating lubricating oil when the input shaft reversely has a suction port having a filter opened in the transmission case on one side and a discharge port opened in the transmission case on the other side; A circulation path opening / closing means that is provided in the circulation path so as to be able to move forward and backward, and closes the circulation path when the input shaft rotates forward and opens the circulation path when the input shaft rotates reversely. The lubricating oil can be circulated between the gear pump and the transmission case by reliably closing the circulation path by the means. Discharge during normal rotation The sucked lubricating oil can be circulated in the gear pump, thus, it is possible to reliably protect the drive gear and the driven gear in the gear pump at the lubricating oil from the friction heat or the like from.

According to the fourth aspect of the invention, in addition to the effects of the third aspect, the circulation path opening / closing means includes a valve seat provided in the circulation path, a plunger chamber connected to the circulation path, A plunger which is accommodated in the plunger chamber so as to be able to advance and retreat, and which has a plurality of communication holes communicating with the valve and the circulation path which can be freely connected to and separated from the valve seat; and And a spring for closing, so that when the input shaft rotates forward, the plunger valve is liquid-tightly joined to the valve seat with the lubricating oil and the spring flowing into the circulation path from the plurality of communication holes of the plunger, thereby ensuring the circulation path. When the input shaft rotates in the reverse direction, the plunger is retracted against the spring by the lubricating oil flowing in from the high pressure side of the circulation path, and the circulation path is reliably opened. It can, this spring for relatively weak biasing force, the plunger valve at the lubricating oil can be opened circulation path easily moved away from the valve seat.

According to the fifth aspect of the present invention, there is provided a machine frame having a three-point connecting portion connected to a tractor, and an input shaft provided on the machine frame protrudably connectable to a power take-out shaft of the tractor. 4 and a rotary work body for ground work, which is rotatably provided on the machine frame and is rotationally driven by an output from an output shaft of the transmission, so that it is interlocked with the rotation of the input shaft. The desired ground work can be performed by the rotary work body that is rotated and driven by the output from the output shaft.

At this time, the rotary working body can be driven to rotate in the downcut direction or the upcut direction by switching the rotation direction of the input shaft according to the work situation. Can be neatly leveled. In addition, the rotation direction of the input shaft is switched to rotate the rotary working body in the upcut direction. When the input shaft is rotated in reverse, lubricating oil is circulated in the reversible pump or the gear pump to reliably protect the reversible pump or the gear pump. Can be. Therefore, the durability of the agricultural work machine can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a mission device showing one embodiment of the present invention.

FIG. 2 is a sectional view of the gear pump.

FIG. 3 is a side view of the gear pump in which a part of the gear pump is cut away.

FIG. 4 is a cross-sectional plan view of the pump body.

FIG. 5 is an explanatory diagram of the gear pump in a state where the circulation path is cut off.

FIG. 6 is an explanatory view of the gear pump in a state where the circulation path is opened.

FIG. 7 is a side view of the agricultural work machine including the mission device.

FIG. 8 is an explanatory diagram of the agricultural work machine in a state where the mission device is cut away.

[Explanation of symbols]

 2 Machine frame 3 Transmission device 5, 7 Connecting part 12 Lubricating oil 13 Transmission case 15 Input shaft 17 Bevel gear 19 Output shaft 21 Interlocking bevel gear 25 Reversible pump 26 Gear pump 34 Circulation path 36 Inlet 38 Filter 51 Discharge port 53 Drive gear 55 Follower gear 59 Circulation path opening / closing means 60 Valve seat 61 Plunger chamber 62 Valve 63 Communication hole 64 Plunger 66 Spring 77 Rotary work body

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Osodo 5-1 Higashinakakanuki-cho, Tsuchiura-city, Ibaraki Pref. Uchida Hydraulic Equipment Co., Ltd. Uchida Hydraulic Equipment Co., Ltd.

Claims (5)

[Claims] A transmission case filled with lubricating oil;
An output shaft rotatably provided on the transmission case and having a bevel gear and having an interlocking bevel gear rotatably provided on the transmission case and meshing with the bevel gear of the input shaft. When the input shaft is rotated and driven, the lubricating oil is sucked when the input shaft rotates forward, discharged and circulated in the transmission case, and the lubricating oil is sucked from the discharge side when the input shaft rotates reversely. And a reversible pump that circulates inside the work machine. 2. The transmission device according to claim 1, wherein the reversible pump comprises a gear pump provided in a transmission case. 3. A gear pump comprising: a drive gear rotatably driven by an output from an input shaft; a driven gear meshed with the drive gear; a suction port having a filter opened in a transmission case on one side; A circulation path which has a discharge port opened in the transmission case on the side and circulates the lubricating oil when the input shaft rotates in reverse, and a circulation path which is provided in this circulation path so as to be able to move forward and backward when the input shaft rotates forward. 3. A mission device for an agricultural work machine according to claim 1, further comprising: a circulation path opening / closing means that closes and opens a circulation path when the input shaft rotates in a reverse direction. 4. A circulation path opening / closing means, comprising: a valve seat provided in the circulation path; a plunger chamber connected to the circulation path; 4. A plunger having a plurality of communication holes communicating with the circulation path, and a spring for urging the plunger to constantly join the valve to the valve seat to close the circulation path.
A mission device for an agricultural work machine according to the above. 5. The transmission device according to claim 1, further comprising a machine frame having a three-point connecting portion connected to the tractor, and an input shaft provided on the machine frame protrudably connectable to a power take-off shaft of the tractor. A rotary work body for ground work, rotatably provided on the machine frame and rotatably driven by an output from an output shaft of the mission device.