JPH031163B2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field
The present invention relates to an oil circulation device in which a transmission case and an oil tank are connected through a pipe, and specifically relates to an oil flow structure from the oil tank.

(B) Conventional technology In general, work vehicles such as combine harvesters are equipped with a large number of hydraulic devices to operate the work equipment, but these hydraulic devices use oil stored in the transmission case as hydraulic oil. It is used as
However, the amount of oil in the transmission case is small, and the agitation of the oil by the transmission and the operation of the hydraulic equipment causes the temperature of the oil to rise rapidly, which has a negative impact on the hydraulic equipment and causes the oil to deteriorate quickly. There is a risk that it will deteriorate and cause maintenance problems.

Therefore, an oil tank is installed in the transmission case via a bypass pipe so that the oil in the oil tank can be used together with the oil in the transmission case to prevent oil temperature from rising and causing oil deterioration. The applicant has proposed an oil circulation device designed to prevent such problems.

(c) Problems to be Solved by the Invention However, in the above-mentioned oil circulation device, depending on the amount of working oil used, the oil tank becomes full, and the oil is returned to the oil tank from the return pipe or from the tank. The back pressure of the oil sent to the transmission case becomes high, and in this case, the diameter of the bypass pipe etc. cannot be increased unnecessarily, so there is a risk that the oil will not be circulated smoothly.

(d) Means for Solving the Problems The present invention aims to solve the above-mentioned problems. For example, as shown in FIGS. 1 and 2, a One end of the flow pipe 50 is connected, and the other end is connected to a position higher than the oil level L of the mission case 12a, so that oil flowing from the oil tank 15 is guided to the mission case 12a. shall be.

(E) Effect Based on the above configuration, depending on the operating conditions of the operating equipment, the oil tank 1 can be closed by the bypass pipe 47.
The amount flowing into the oil tank 15 from the hydraulic equipment via the return hose 45 may be larger than the amount flowing out from the hydraulic equipment 5 to the transmission case 12a. In this case, the oil tank 15 becomes full and the flow Oil flows from the upper surface 15a through the flow pipe 50 to the transmission case 12a.

(F) Embodiments Hereinafter, embodiments in which the present invention is applied to a combine harvester will be described with reference to the drawings.

As shown in FIG. 6, the combine 1 has a body 3 supported by a crawler 2, and a driver's seat 5, a grain tank 6, and an engine 7 are arranged from the front on one side of the body. An automatic threshing machine 9 is installed on the other side. Further, a preprocessing section 10 is supported at the front of the fuselage 3 so as to be able to rise and fall freely, and the preprocessing section 10 includes a large number of dividers 11,
A raking device, a cutting blade, a grain culm conveying device, etc. are installed. Further, a transmission case 12 and a counter case 13 are arranged inside the machine body of the driver's seat 5, and an oil tank 15 is arranged inside the machine body of the grain tank 6.

Further, as shown in FIG. 7, the mission case 12 includes a main case 12a and a sub case 12b.
The main case 12a includes a forward hydraulic clutch 16, a reverse hydraulic clutch 17, left and right side clutches 19l, 19r, and left and right brakes 20.
l, 20r, and left and right axles 21... are disposed, and the sub case 12b has an auxiliary transmission gear 22,
A pre-processing section transmission gear 23 is provided. Furthermore,
A sprocket 25 is fixed to each of the left and right axles 21 protruding from the main case 12a.
These sprockets 25 are engaged with the crawler 2. In addition, the shaft 2 protruding from the sub case 12b
A driven speed change pulley 29b equipped with a main clutch 27 is supported by the drive side speed change pulley 29b, which is equipped with a main clutch 27.
1 is wound around to form a continuously variable transmission 29. In addition, the counter case 13 includes a hydraulic pump 3.
2 is installed, and the pump 32 is connected to the engine 7.
The continuously variable transmission 29
is driven together.

As shown in FIGS. 2 to 4, the main mission case 12a is disposed at the lower part of the fuselage at approximately the center in the left-right direction of the fuselage, and the main mission case 12a is disposed at approximately the same level in the case 12a. forward and reverse hydraulic clutch 16,
17 is filled with oil so as to partially cover the case 12a (see oil level L in FIGS. 1 and 2), and these hydraulic clutches 1 are placed on the case 12a.
A valve device 35 for controlling 6 and 17 is installed. Further, the counter case 13 is disposed diagonally rearward and upwardly of the mission case 12, and a hydraulic pump 3 is further installed on the counter case 13.
A valve unit 37 to which hydraulic pressure is supplied from 2 through a delivery pipe 36 is connected to the seat 5a of the driver's seat 5.
placed below. Also, oil tank 15
is located between the two square pipes 39, 39 that make up the fuselage frame, as shown in detail in FIG.
The lower surface 15b of the tank 15 is supported by a plate 40 that connects these pipes 39, and thus the tank 15 is protected from obstacles by these square pipes 39. Further, a filter 41 is installed above the oil tank 15 and below the hydraulic pump 35.
1 and the counter case 13 are arranged in the center of the machine by a space S created by the slope 6a of the grain tank 6 for grain flow down.

As shown in FIG. 1, a suction pipe 42 with a rubber pipe 42a interposed in the middle extends from the lower part of the main transmission case 12a toward a filter 41.
From there, a suction pipe 43, which also has a rubber pipe 43a in the middle, extends toward the hydraulic pump 32. Further, from the valve unit 37, a first return hose 45 extends toward the oil tank 15, and a second return hose 45 extends toward the oil tank 15.
6 extends toward the valve device 35 and the main transmission case 12a. Further, the oil tank 15 and the main transmission case 12a are communicated with each other by a bypass pipe 47 having a rubber pipe 47a, and as shown in detail in FIG.
The bypass pipe 47 is extended in parallel with the suction pipe 42 and the clamp 49, and is open adjacent to the case 12a.

Further, the upper surface 15a of the oil tank 15 and the upper part of the main transmission case 12 are communicated by a flow pipe 50, and as shown in detail in FIGS. 1 and 2, the case connection part of the flow pipe 50 is is constructed by fitting a large-diameter pipe 52 connected to a flow pipe 50 into a large-diameter pipe 51 fixed to the case 12a and located above the forward/reverse hydraulic clutches 16, 17 in side view. Furthermore, a plurality of washers 53 are fixed to the small diameter pipe 52 to form a labyrinth consisting of a small gap A between the small diameter pipe 51 and the pipe 55.
It communicates with the breather pipe 56 via. Therefore, the oil flowing from the flow pipe 50 to the main transmission case 12a is transferred to the small diameter pipe 52.
The breather pipe 56 also serves as a breather for both the transmission case 12 and the oil tank 15. In addition, in the figure, 57 is an oil filler port of the oil tank 15. Further, as shown in FIG. 3, a partition plate 59 is installed in the oil tank 15 so as to separate the opening of the return hose 45 and the opening of the bypass pipe 47, so that oil flows from the return hose 45 to the bypass pipe 47.
This prevents direct inhalation.

As shown in detail in FIG. 1, the upper surface 15a of the oil tank 15 is located at a position slightly higher than the oil level L of the transmission case 12, and therefore the oil tank 15 has an air section formed by a small gap H. The oil level is set so that In addition, as shown in detail in FIG. 3, the oil tank 15
The main transmission case 12a is installed at approximately the center of the fuselage at approximately the same position with respect to the fuselage center line when viewed from above.

Further, FIG. 8 is a diagram showing a hydraulic circuit that operates each operating device of the present combine. In the figure, 60 is a flow divider, and a small amount of oil flows into the constant pressure side oil path a, and the hydraulic clutches 16, 17 Control valve device 3
5, and a large amount of oil flows through the fluctuating pressure side oil path b, which controls the grain tank control hydraulic equipment 61, the pre-processing section control hydraulic equipment 62, the side clutch control hydraulic equipment 63, and the continuously variable transmission control. hydraulic equipment 65 and hydraulic equipment 66 for controlling the handbrake.

Since this embodiment has the above-described configuration, rotation from the engine 7 is transmitted to the shaft 30 of the counter case 13, and further transmitted to the continuously variable transmission 29 and to the hydraulic pump 32. The rotation, which has been appropriately changed in speed by the continuously variable transmission 29, is transmitted to the pre-processing section 10 via the gears 22 and 23 in the sub-case 12b, and is also transmitted to the forward clutch 16 and the forward clutch in the main transmission case 12a. The transmission is transmitted to the reverse clutch 17, and forward or reverse rotation based on the connection of these clutches 16 or 17.
The power is transmitted to the left and right axles 21 via the left and right side clutches 19l and 19r, or the axle 21 is braked by the left and right side brakes 20l and 20r, and the crawler 2 is driven by a sprocket 25 fixed to the axle 21 to drive the combine 1. run.

On the other hand, the hydraulic pressure driven by the hydraulic pump 32 is supplied by a flow divider 60 to the valve device 35 of the hydraulic clutches 16 and 17 for forward and backward movement, and also to the hydraulic equipment 61 for controlling the grain tank and the hydraulic equipment for controlling the pre-processing section. 62, is supplied to the side clutch control hydraulic equipment 63, the continuously variable transmission control equipment 65, and the side brake control hydraulic equipment 66, and based on appropriate control of these hydraulic equipment, the forward clutch 16 and the reverse clutch 17 are disconnected. Contact operation, movement of the grain transfer cylinder of the grain tank 6, lifting and lowering operation of the pre-processing section 10, left and right side clutches 19l, 1
The connecting/disconnecting operation of 9r, the speed change operation of the continuously variable transmission 29, and the braking operation of the left and right side brakes 20l and 20r are performed.

Based on the drive of the hydraulic pump 32, oil is sucked into the suction pipe 42 from the lower part of the main transmission case 12a, and further into the pump 32 through the filter 41 and the second suction pipe 43. The oil discharged from the pump 32 is sent to the valve unit 37 via the delivery pipe 36, sent to each hydraulic device by the flow divider 60 in the valve unit 37, and then the oil in the flow divider 60 is sent to the valve unit 37. A large flow of oil based on path b is returned to the return hose 45.
is discharged to the oil tank 15 via
A small flow of oil based on the oil reservoir a is sent to the forward/reverse valve device 35 via the second return hose 46 and is discharged into the main case 12a. At this time, for example, when the hydraulic pump 32 discharges 15 oils per minute, 12 oils are discharged to the first return hose 45 and 3 oils are discharged to the second return hose 46. From the oil tank 15, 13
of oil will be returned.

In addition, as shown in FIG. 5, the bypass pipe 4
7 and the suction pipe 42 are open adjacent to the main transmission case 12a, so that almost all of the oil from the suction pipe 42 (12) is sucked into the suction pipe 42, and is also removed from the main case 12a. The remaining amount (3) is sucked in, circulates the oil in the main case 12a, and prevents it from becoming hot.

Note that, in reality, the entire amount from the return hose 45 does not flow into the bypass pipe 47;
The amount of suction from the main case 12a will inevitably be large, and the amount of discharge from the return hose 45 will also vary depending on the usage status of the hydraulic equipment.
The oil tank 15 tends to become full. Therefore, when the oil tank 15 becomes full, oil flows from the oil tank 15 to the main case 12a through the flow pipe 50. The flow oil then flows over the forward and reverse hydraulic clutches 16 and 17 to lubricate and cool them, as shown in FIG. In addition, a small diameter pipe 52 constituting the flow pipe 50
Around the labyrinth A consisting of washers 53
There is a breather pipe 56 via the main case 12a, and therefore the oil case 15
The upper part of the oil level is also communicated with the atmosphere through the flow pipe 50, and the labyrinth A suppresses the oil blown out from the main transmission case 12a by the tampering action of the damper chambers 51a and 51b, so that the oil It is configured so that it does not blow out to the breather pipe 56.

(G) Effects of the Invention As explained above, according to the present invention, the transmission case 1 is
Since the flow pipe 50 is connected to a position higher than the oil level L of the oil tank 2a and is configured to guide the oil flowing from the oil tank 15 to the case 12a, a large amount of oil returns to the tank 15 due to oil circulation. When the oil tank 15 becomes full, excess oil immediately flows out from one end of the flow pipe 50 into the transmission case 12a, thereby preventing the back pressure caused by the oil tank 15 from increasing. Therefore, although the oil tank 15 and the transmission case 12a are communicated with each other with a simple structure, it is possible to maintain proper oil circulation and prevent the temperature of the oil from rising, thereby providing high reliability to the hydraulic equipment. You can get sex.

Furthermore, the connection position of the other end of the flow pipe 50 to the transmission case 12a is changed to the hydraulic clutch 1 located partially above the oil level L in the case 12a.
6, 17 above, the oil sent from the oil tank 15 via the flow pipe 50 can be poured into the hydraulic clutches 16, 17, thereby facilitating the lubrication and cooling of the clutches 16, 17.

[Brief explanation of the drawing]

Fig. 1 is a side view showing the oil circulation device according to the present invention, Fig. 2 is a cross-sectional view showing the flow pipe connected to the transmission case, Fig. 3 is a plan view of the oil circulation device, and Fig. 4 is the same. The rear view and FIG. 5 are cross-sectional views showing the connection portions of the return pipe and the suction pipe to the mission case. FIG. 6 is a side view showing a combine harvester to which the present invention is applied, FIG. 7 is an expanded sectional view showing its power transmission device, and FIG. 8 is a diagram showing its hydraulic circuit. 1... Work vehicle (combine harvester), 12a... Mission case (main), 15... Oil tank, 15a... Tank top surface, 16, 17... Hydraulic clutch (forward hydraulic clutch, reverse hydraulic clutch), 32... Hydraulic pump, 35, 37... Hydraulic equipment (valve unit, valve device), 47...
...Bypass pipe, 50...Flow pipe, L...
...Oil level.

Claims (1)

[Scope of Claims] 1. A hydraulic device is provided for operating and operating a transmission case, an oil tank, and various operating devices, and a hydraulic pump sucks oil in the transmission case and discharges it toward the hydraulic device, and In a work vehicle configured to return oil to the oil tank, and in which the oil tank is connected to the transmission case via a bypass pipe, one end of a flow pipe is connected to the upper surface of the oil tank, and the other end is connected to the upper surface of the oil tank. An oil circulation device for a working vehicle, which has an end connected to a position higher than the oil level of the transmission case to guide oil flowing from the oil tank to the transmission case. 2. The oil circulation system for a work vehicle according to claim 1, wherein the other end of the flow pipe is connected to the transmission case above a hydraulic clutch that is partially located above the oil level in the case.