JPH0225011Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a hydraulic pump mounting structure for a mobile agricultural machine.

[Prior art]

In the case of conventional hydraulic pumps that are installed on mobile agricultural machines and supply pressure oil, the return oil from the hydraulic pump or the return oil from the switching valve and hydraulic telescoping mechanism is equal to the oil level in the oil tank. Or it was supposed to be returned above the oil level.

In addition, for mobile agricultural machinery such as combines,
In the past, the general structure of a combine was to be equipped with a hydraulic expansion and contraction device that raised and lowered the pretreatment device, but recently it has also been equipped with a hydraulic expansion and contraction device that engages and engages the clutch of the traveling device, and the oil circulation The amount has also increased.

However, especially in small combine harvesters, the oil tank for supplying pressure oil to these multiple hydraulic expansion and contraction devices drives the hydraulic pump due to the compact arrangement of the overall functional devices that make up the small combine harvester. It has a small-capacity construction that also serves as an intermediate shaft case with a built-in transmission mechanism for the purpose of servicing, and is not equipped with a dedicated large-capacity oil tank. The oil is diffused by the gears in the case, and as mentioned above, the returning oil returns from the oil level or above the oil level, which generates air bubbles and gradually becomes cloudy. The cooling capacity of the oil decreases and the oil temperature rises, causing it to deteriorate relatively quickly, resulting in problems such as abnormal sounds from the hydraulic pump and cavitation.

[Purpose of invention]

The present invention was devised in view of the above-mentioned conventional situation and to eliminate the drawbacks thereof, and the present invention is to return the return oil from the hydraulic pump and the switching valve to a position below the oil level in the intermediate shaft case. This eliminates air bubbles generated by return oil that is equal to or higher than the oil level stored in a small intermediate shaft case that also serves as an oil tank, and eliminates the early clouding of oil that is caused by this. It is an object of the present invention to provide a hydraulic pump mounting structure for a mobile agricultural machine that can prevent deterioration.

[Structure of the idea]

The hydraulic pump mounting structure of the present invention for a mobile agricultural machine that achieves the above object has a mounting surface of a hydraulic pump case in which a return oil passage from a relief valve provided on the hydraulic pump and a return oil passage from a switching valve are formed. ,
It is fixed to the side surface of the intermediate shaft case that also serves as an oil tank, and is connected to the return oil path of the relief valve on the mounting surface of the hydraulic pump case, and extends below the oil level in the intermediate shaft case. A guide oil path is formed, a return oil path from the switching valve is communicated with the guide oil path, and the lower part of the guide oil path is communicated with the inside of the intermediate shaft case through a return hole opened in the intermediate shaft case. This is a characteristic feature.

〔Example〕

Hereinafter, the present invention will be described with reference to the drawings showing one embodiment.

FIG. 1 is a side view of a combine harvester embodying the present invention. In this case, the intermediate shaft case 5 is fixedly disposed.

An intermediate pulley 7 fixed to the shaft end of an intermediate shaft 6 rotatably provided in the intermediate shaft case 5, and the prime mover 2
Between the output shaft 8 and the fixed prime mover pulley 9,
A V-belt 10 is wound around a tension pulley 11, and the power of the prime mover 2 is transmitted to the intermediate shaft 6 of the intermediate shaft case 5.

Further, a split pulley type continuously variable transmission 13 is provided between the intermediate shaft 6 of the intermediate shaft case 5 and the traveling drive shaft 12 of the traveling transmission case 4. The drive side split pulley is
It is composed of a fixed pulley 14 and a movable pulley 15 that face each other on the intermediate shaft 6, and the driven side split pulley of one of the continuously variable transmissions 13 is connected to a fixed pulley 74 and a compression spring 76 provided on the traveling drive shaft 12. The movable pulley 75 moves so that the distance between the fixed pulley 74 and the fixed pulley 74 expands and contracts. 16 is wound around the drive shaft 16, and the continuously variable transmission device 13 continuously changes the speed of the rotation of the travel drive shaft 12.

A pretreatment drive shaft 20 is rotatably supported on the intermediate shaft case 5 and is driven via a large gear 19 that meshes with a small gear 18 fixed to the intermediate shaft 6. The protruding portion 20a on the opposite side to the intermediate shaft 6 is a pre-processing device 2 for harvesting the standing grain culm 21 and conveying it to the rear automatic threshing device 22.
3, and the intermediate shaft 6
The protruding portion 20b in the same direction is provided with an eccentric cam 24 eccentric from the axis of the pretreatment drive shaft 20 and a rod 25 connected to the eccentric cam 24, which drive the cutting blade 26. There is.

Further, a support hole 27 formed around the axis of the pretreatment drive shaft 20 of the intermediate shaft case 5, and a support hole 27 formed around the axis of the pretreatment drive shaft 20 of the intermediate shaft case 5
A pre-processing drive shaft case 29 is rotatably supported between the supporting part 28 and the supporting part 28 facing at a predetermined distance from each other. Pre-treatment transmission case 3
By the expansion and contraction of a hydraulic expansion/contraction mechanism 31 provided between the support section 2 and the machine body, the support section 2
8 is fixed to a support 32, and this support 32 is fixed to a fixed pipe 33 fixed to the fuselage.

A pump drive shaft 35 is rotatably supported on the intermediate shaft case 5, and a pump drive gear 34 fixed to the pump drive shaft 35 meshes with the large gear 19 of the pretreatment drive shaft 20 to rotate. and
This pump drive shaft 35 has a connecting mechanism 3 formed at the shaft end.
A hydraulic pump 37a formed of a gear pump is driven and rotated by being connected to a pump shaft 35a built in a hydraulic pump case 37 fixed to an outer wall side surface 5a of the intermediate shaft case 5 via a shaft 6. .

In the present invention, the mounting surface 37c of the hydraulic pump case 37 is superimposed and fixed to the side surface 5a of the intermediate shaft case 5 via the packing 90. The mounting surface 37c is provided with a return oil passage 66 from a relief valve 48 integrally provided in the hydraulic pump case 37 as shown in FIG. 6, and a return oil passage 46 from a switching valve 39 to be described later. However, the return oil holes 46 and 66 are connected and communicated with a guide oil passage 65 extending below the oil level L in the intermediate shaft case 5 formed on the mounting surface 37c of the hydraulic pump case 37. A gasket 90 that closes the mounting surface side of the guide oil passage 65 provided in the hydraulic pump case 37 and a side face 5a of the intermediate shaft case are provided with a gasket 90 located below the guide oil passage 65 and inside the guide oil passage 65 and inside the intermediate shaft case 5. The return hole 47 is opened to communicate with the intermediate shaft case 5, and the return oil from the relief valve 48 and the return oil that has passed through the switching valve 39 are transferred to the intermediate shaft case 5 through the guide oil passage 65 extending downward. Oil level L
It is designed to return downwards.

As shown in FIG. 8, the bag 90 has a hole 88 that communicates with the return oil passage 46 provided in the hydraulic pump case 37 and into which the mounting portion is fitted, and a hole 88 that communicates with the inside of the strainer 41.
9 is open, and this buckle 90 closes the mounting surface side of the guide oil passage 65 provided in the hydraulic pump case 37. Furthermore, code 87
is an insertion hole for a mounting bolt when the hydraulic pump case 37 is superimposed and fixed to the side surface 5a of the intermediate shaft case 5.

The inside of the intermediate shaft case 5 is also used as a small oil tank 5 in which oil that also serves as lubricating oil is stored up to the oil level L position shown in FIG. The hydraulic pump 37a is supplied from the suction oil passage 42 provided in the hydraulic pump case 37 via the filter 41 disposed laterally in the corresponding lower part.
After being sucked into the oil passageway 43, the oil is discharged through a discharge oil passage 43. Note that the reference numeral 91 is an oil check plug provided at the oil level L position.

Also, the rear side 37 of this hydraulic pump case 37
In b, there are two rotary valve type switching valves 38 and 3 that can individually switch the discharge oil passages 43 provided in the hydraulic pump case 37.
Valve cases 40 are arranged side by side at intervals in the front-rear direction so that the valve cases 9 rotate about axes in directions that intersect with each other, and are arranged in an overlapping manner. In case 40,
Two switching valves 38 and 39 are arranged side by side with an interval in the front-rear direction, and are provided so as to intersect with each other at right angles.

A valve arm 52 is fixed to the front switching valve 38 disposed close to the hydraulic pump 37a.
is connected to a pretreatment lift operation lever 60 disposed near the driver's seat 49 via a connection member to be described later,
As shown in FIG.
It is designed to be selectively rotated between the DOWN position and the UP position.

In other words, the valve arm 52 described above has the ninth
As shown in FIG. 10, a vertical connecting pin 55 is fixed, and a horizontal connecting pin 55 is fixed to an extension of a mounting seat 56 whose base end is fixed to the mating part 5b of the intermediate shaft case 5. The bearing metal 57 is fixed,
This bearing metal 57 is provided with a pivot pin 58 that is rotatably supported, and the lower elongated hole of the connecting rod 59 whose upper side is fixed to the pivot pin 58 is connected to the connecting pin of the valve arm 52. 55, and this pivot pin 58 is provided with a regulation spring 84 that fits into the outer diameter of the pivot pin 58, and the base end side of the connector 83 is fixed on the back side of this regulation spring 84. , a connecting pin 85 that swings around the axis of the rotating pin 58 is provided on the tip side of the connector 83.
is fixed, and the proximal end side of the horizontal connecting rod 85 is rotatably supported by the connecting pin 85. The distal end side of the horizontal connecting rod 85 is rotatably connected to the aforementioned pretreatment lifting/lowering operation lever 60. There is.

Therefore, by operating the pre-treatment lifting/lowering operation lever 60, the connecting rod 85 moves, and this connecting rod 85
As a result of this movement, the connector 83 swings in the direction of the arrow around the axis of the rotation pin 58, thereby moving the front switching valve 38 via the valve arm 52 to the neutral N position, DOWN position, or It is designed to be switched to the UP position.

Further, the valve arm 53 fixed to the switching valve 39 on the rear side, which is disposed further away from the hydraulic pump 37a, is automatically set to the ON position at all times by a tension spring 54 provided between the valve arm 53 and the aircraft body. It is energized to return and is further arranged near the driver's seat 49 via a connecting member consisting of an inner wire 61 connected to the valve arm 53 and an outer wire 62 fixed to the mating portion 5b of the intermediate shaft case 5. The gear shift operating lever 63 is connected to a shift operating lever 63 which is formed in an operating guide groove 82 shown in FIG.
As shown in FIG. 9, the valve arm 53 selectively rotates between the ON position and the OFF position in conjunction with the ON and OFF operations at the reverse R position.

The pretreatment hydraulic expansion/contraction device 31 includes a switching valve 3 that responds to the operation of a pretreatment lifting/lowering operation lever 60.
It is designed to expand and contract by switching 8. In other words, as shown in the hydraulic circuit diagram shown in Fig. 14, the front switching valve 38 is moved up from the neutral position N.
When switched to the position, the pressure oil in the discharge oil passage 43 passes through the oil passage 44 provided in the switching valve 38 and is supplied to the pretreatment hydraulic expansion and contraction device 31 via the oil passage CI. The hydraulic expansion/contraction device 31 is expanded, and the pretreatment device 23 is raised about the axis of the pretreatment drive shaft 20 .

When lowering the pretreatment device 23 in this raised position, the front switching valve 38 is moved from the neutral position N.
Switch to DOWN position. In this DOWN position, the pressure oil in the hydraulic expansion/contraction device 31 passes through the oil path C1, the oil path 44, and returns via the return oil path 51, so the pretreatment device 23 descends under its own weight. There is.

In addition, as shown in FIG. 12, on the traveling transmission case 4 side, there is a transmission gear that can only slide freely between forward F, neutral N, and reverse R, which is disposed on the traveling drive shaft 12 inside the traveling mission case 4. 67 are provided,
The above-mentioned speed change operation lever 63 is connected to this speed change gear 67 via a shifter (not shown), and a fixed cam 68 fixed to this traveling transmission case 4,
A movable cam 69 that moves in the axial direction around the axis of the traveling drive shaft 12 is disposed with respect to the fixed cam 68, and a movable cam 69 is disposed on the traveling drive shaft 12 outside of this movable cam 69. The relay bearing 70 moves in the axial direction on the traveling drive shaft 12 by the movement of the relay bearing 7.
Disc 7 fixed to traveling drive shaft 12 as movement of
1 and a dry veneer 72 that can freely rotate with respect to the traveling drive shaft 12. It is engaged inside a fixed pulley 74 in the form of a split pulley that is rotatably supported.

a moving cam 69 for actuating the clutch mechanism 73;
is a constant clutch mechanism 7 using a spring (not shown).
It is supported so that 3 is in the ON position,
Also, connecting pins 76 and 77 are provided on both sides of the moving cam 69.
The connecting pin 76 on one side is operatively connected to a foot pedal (not shown) via a connecting member, and is further connected to a piston 81 connected to a connecting pin 77 on the other side and a fixed pin 78 fixed to the fuselage. cylinder 7
The moving cam 69 is connected to a hydraulic telescoping mechanism 80 for the clutch consisting of a foot pedal and a manual operation of the gear shift operating lever 63 via the hydraulic telescoping mechanism 80. It is now ready for operation.

A hydraulic expansion/contraction device 80 for a clutch that operates this clutch mechanism 73 operates a switching valve 39 on the rear side that is linked to a speed change operation by a speed change operation lever 63.
Clutch mechanism 73 is activated by switching to ON and OFF positions.
It is becoming a non-clutch shifting system that intermittents.

In other words, as shown in the hydraulic circuit diagram shown in FIG. 14, the front switching valve 38 is in the neutral N position (or
DOWN 1 position), shift control lever 6
By operating step 3, the rear switching valve 39 is
When switched to the ON position, the pressure oil in the discharge oil passage 43 passes through the switching valve 38, via the oil passage 45, passes through the switching valve 39 in the ON position, reaches the return oil passage 46, and returns oil from the relief valve 48. Similarly, a return hole 47 opened below the oil level L of the intermediate shaft case 5 via a guide oil path 65 connected to this return oil path 46.
At the same time, the pressure oil in the hydraulic expansion and contraction mechanism 80 also returns to the oil tank 5 due to the biasing force of the subring disposed on the moving cam 69. The clutch mechanism 73 is in the [on] state. At this time, since the variable throttle valve 50 is in the return oil path and the return of the hydraulic expansion/contraction device 80 is slow, the hydraulic expansion/contraction device 80 returns quickly and the clutch mechanism 73 is suddenly connected, causing a large impact and causing discomfort to the operator. Never give up.

In addition, when the front side switching valve 38 is in the neutral N position (or DOWN 1 position),
When the switching valve 39 on the rear side is switched to the OFF position by operating the shift operation lever 63, the oil passage leading to the return oil passage 46 via the switching valve 39 is blocked, and the pressure oil is transferred to the intermediate shaft case 5. Instead of returning to the internal oil tank 5, the pressure rises to the set pressure of the relief valve 48 mechanism, and the pressure oil with this increased pressure passes through the variable throttle valve 50 and is sent to the hydraulic expansion and contraction device via the oil path C2. 80, the hydraulic expansion/contraction device 80 is expanded, the moving cam 69 is rotated, and the clutch mechanism 73 is brought into the "disengaged" state via the relay bearing 70. At this time, the return oil from the hydraulic pump 37a side that has passed through the relief valve 48 descends through the downward guided oil path 65, and then flows through the opening hole 47 below the oil level L to the oil tank 5 which also serves as the intermediate shaft case 5. will be returned. At this time, with the switching valve 38 disposed on the front side in the neutral N position (or DOWN 1), switch the switching valve 39 on the rear side.
A hydraulic circuit configured to switch between ON and OFF so that the rear switching valve 39 is not switched at the UP position of the front switching valve 38;
By prioritizing the raising of the pre-treatment device 23 by the hydraulic telescopic mechanism 31 and preventing simultaneous operation of this and the engagement/disconnection of the clutch by the hydraulic telescopic mechanism 80, the hydraulic pump 37a and the intermediate shaft case 5 are
The dual-purpose oil tank 5 can be small and have a small capacity.

Therefore, in the present invention, the structure is simple and easy to process using the guide oil passage 65 extending below the oil level L in the intermediate shaft case 5 formed on the mounting surface 37c of the hydraulic pump case 37. With this, the oil returned from the relief valve 48 is transferred to the hydraulic telescopic mechanism 31,
The oil level L in the oil tank 5 along with the return oil from 80
It can be returned to a lower position. For this reason, unlike conventional models in which the return oil is returned to a level equal to or above the oil level in the oil tank, air bubbles generated by the return oil are eliminated, and this causes an intermediate shaft that also serves as an oil tank. Eliminates problems such as the small volume of oil in the case becoming cloudy or deteriorating relatively early, causing abnormal sounds in the hydraulic pump and cavitation, and preventing early clouding and deterioration of oil. be able to.

[Effect of idea]

In short, the hydraulic pump mounting structure for a mobile agricultural machine according to the present invention uses the mounting surface of the hydraulic pump case, in which the return oil passage from the relief valve provided on the hydraulic pump and the return oil passage from the switching valve are formed, to The induction oil is fixed to the side surface of the intermediate shaft case which also serves as a tank, and is connected to the return oil path of the relief valve on the mounting surface of the pump case and extends below the oil level in the intermediate shaft case. A return oil passage from the switching valve is communicated with the induction oil passage, and the lower part of the induction oil passage is communicated with the interior of the intermediate shaft case through a return hole opened in the intermediate shaft case. The return oil can be returned to the intermediate shaft case below the oil level using the easy-to-process oil path formed on the mounting surface of the pump case, so the interior of the intermediate shaft case can also be used as an oil tank. Despite using a small oil tank, this method eliminates the air bubbles generated by the returned oil, unlike conventional models that return the returned oil to a level equal to or above the oil level in the oil tank. As a result, the small volume of oil in the intermediate shaft case, which also serves as an oil tank, becomes cloudy or deteriorates relatively quickly, causing problems such as abnormal sounds from the hydraulic pump and cavitation. This can prevent early clouding and deterioration of oil.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention,
Figure 1 is a side view of the combine, Figure 2 is an enlarged side view of the intermediate shaft case, Figure 3 is a plan development of the intermediate shaft case, and Figure 4 is an enlarged view of the valve case and hydraulic pump. Figure 5 is the front view shown in Figure 4.
6 is a rear view showing the mounting surface of the hydraulic pump, and FIG. 7 is a sectional view taken along the arrow B-B in the figure.
A partial sectional view in the direction of the O-C arrow, FIG. 8 is a front view of the buckle, FIG. 9 is a side view showing the connection structure of the switching valve, FIG. 10 is a rear view of FIG. 9, and FIG. FIG. 12 is a plan view showing a portion of the traveling transmission case, FIG. 13 is a plan view showing the guide groove of the gear shift operation lever, and FIG. 14 is a hydraulic circuit diagram. 5... Intermediate shaft case, 5a... Side, 37...
Hydraulic pump case, 37a...Hydraulic pump, 37
c...Mounting surface, 38, 39...Switching valve, 40
... Valve case, 31, 80 ... Hydraulic expansion mechanism, 46 ... Return oil path, 47 ... Return hole, 65 ...
...Guidance oil path, 66...Return oil path.

Claims (1)

[Scope of utility model registration request] The mounting surface of the hydraulic pump case, on which the return oil passage from the relief valve and the return oil passage from the switching valve provided in the hydraulic pump are formed, is superimposed and fixed to the side of the intermediate shaft case, which also serves as an oil tank. No, a guide oil passage is formed on the mounting surface of the hydraulic pump case, which connects to the return oil passage of the relief valve and extends below the oil level in the intermediate shaft case, and the guide oil passage is connected to the return oil passage of the relief valve and extends below the oil level in the intermediate shaft case. A hydraulic pump mounting structure for a mobile agricultural machine, characterized in that a return oil passage is communicated, and a lower part of the guide oil passage is communicated with the inside of the intermediate shaft case through a return hole opened in the intermediate shaft case.