JPS64361Y2 - - Google Patents

Description

[Detailed description of the invention] The invention relates to a hydraulic pressure take-off circuit for a tractor.
The purpose is to facilitate the disassembly and assembly of the tractor body and hydraulic circuit, to take out hydraulic pressure to a large number of hydraulic working parts, and to reduce costs.

In tractors for agricultural and civil engineering construction, a hydraulic system is installed at the rear of the vehicle body, and in addition to hydraulically controlling the rear working equipment so that it can be raised and lowered via a three-point link mechanism, the front of the vehicle body is equipped with a loader, blade, etc. for front loading work. Loading and unloading work and ground leveling work are sometimes carried out using hydraulic cylinders, and there are also cases where a hydraulic clutch is used for the transmission changeover mechanism of the transmission. Pressure oil is supplied to hydraulic working parts such as a hydraulic cylinder of a working machine and a hydraulic clutch of a transmission by extracting pressure oil from a discharge side oil passage leading from a hydraulic pump to a hydraulic device.

In a conventional hydraulic extraction circuit, a hydraulic extraction device is provided near the hydraulic system, and pressure oil is supplied from this hydraulic extraction device to each hydraulic working part via a hose or pipe, and the pressure oil is supplied from the hydraulic extraction device to the front or center of the vehicle body. A long hose or pipe is required to reach the hydraulic work part located in the
The production cost is high, and the hydraulic pump is installed on the side of the engine and connected to the hydraulic system with a pipe that forms the discharge oil passage, but the car body is directly connected so that it can be divided into front and rear parts. Therefore, when disassembling and reassembling the car body, the pipes must also be connected and disconnected.If the pipes could be connected and disconnected midway, disassembly and reassembly would be troublesome and production costs would be high.Furthermore, even if the number of hydraulic working parts increases or decreases, It was difficult to increase or decrease the number of hydraulic pressures taken out.

The present invention solves all of these conventional problems, and its feature is that the vehicle body 5 is formed by directly connecting the engine 2, clutch housing 3, and transmission case 4 so that they can be divided into front and rear parts. A hydraulic circuit 10 is formed to supply pressure oil from a hydraulic pump 11 provided on the side of the engine 2 to a hydraulic device 7 provided at the rear upper part of the transmission case 4 via a discharge oil passage 14. A hydraulic pressure extraction device 16 mounted near the vehicle body division position 48 is disposed midway through the path 14, and this hydraulic pressure extraction device 16
A hydraulic outlet body 43 in which a suction passage 49 and a discharge passage 50 are formed and communicated with the discharge side oil passage 14; In a hydraulic pressure extraction circuit for a tractor, which is equipped with a lid connecting body 44B in which a hydraulic pressure extraction oil passage communicating with the suction oil passage 49 and the discharge oil passage 50 is formed to supply oil, the oil pressure extraction device 16 is , a suction oil passage 49 on the periphery to be connected to the second hydraulic working part and supply pressure oil.
It has an outflow passage 54 communicating with the discharge passage 50 and an inflow passage 56 communicating with the discharge passage 50, and is interposed between the hydraulic pressure extraction body 43 and the lid connection body 44B, and is connected to the hydraulic pressure extraction body 43 in common with the lid connection body 44B. Middle connecting body 4 to be tightened
4A is provided.

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, a tractor 1 has an engine 2 mounted near the front, and a clutch housing 3 is directly connected to the rear of the engine 2, and a transmission case 4 is directly connected to the rear of the engine 2 so that they can be divided into front and rear parts to form a vehicle body 5. The inside of the transmission case 4 is used as an oil tank 6.

Reference numeral 7 denotes a hydraulic system disposed at the rear upper part of the vehicle body 5, which has a pair of left and right lift arms 8, and is capable of freely raising and lowering a rear-mounted working machine mounted via a three-point linkage mechanism.

10 is a hydraulic circuit for a tractor, which includes a hydraulic pump 11 mounted on the side of the engine 2 and driven;
This hydraulic pump 11 and oil tank 6 are connected to a filter 1.
2, a discharge side oil passage 14 that connects the hydraulic pump 11 and the hydraulic device 7 via the control valve 9, and the hydraulic device 7 and the oil tank 6. A hydraulic pressure extraction device 16, which will be described later, is disposed midway through the discharge side oil passage 14.

Reference numeral 17 denotes a front loader disposed at the front of the vehicle body 5, which includes a support frame 18 detachably provided in the middle of the vehicle body 5, and a lift extending forward from the top of the support frame 18 so as to be vertically movable. arm 19 and a bucket 20 pivotally supported at the front end of the lift arm 19
It has a lift cylinder 21 that raises and lowers the lift arm 19, and a bucket cylinder 22 that causes the bucket 20 to perform dumping and scooping operations,
The lift cylinder 21 and bucket cylinder 2
2 is hydraulically controlled by a loader control valve 23.
is connected to the hydraulic pressure extraction device 16 via a feed pipe 24 and a return pipe 25, and both cylinders 21 and 22 serve as a hydraulic working section.

In the transmission case 4, a forward/reverse transmission having the same number of forward and reverse gears as shown in FIG. 2 is arranged. 27 is a main clutch, 28 is a forward/reverse transmission mechanism, and has a forward rotation hydraulic clutch 29 and a reverse rotation hydraulic clutch 30 (both are hydraulic working parts).
31 is a main transmission mechanism, 32 is a creep transmission mechanism, 3
Reference numeral 3 designates sub-transmission mechanisms, and the driving force from the engine 2 is transmitted from the main clutch 27 to the rear differential gear 3 via the respective transmission mechanisms 28, 31, 32, and 33.
4.

Reference numerals 35 and 36 denote a first mechanism and a second mechanism for PTO shifting which are arranged separately in the front and rear, and the power from the main clutch 27 is transmitted without passing through the forward and reverse clutches 29 and 30, so that the PTO shaft 37 is always It is driven in one direction.

The forward and reverse clutches 29 and 30 are connected to the oil supply path 3.
It is connected to a forward/reverse control valve 41 via 9 and 40. Although the oil supply passages 39 and 40 may be formed by pipes, they are usually formed within the wall of the clutch housing 3, and the forward/reverse control valve 41 is mounted on the clutch housing 3.

In FIGS. 1 to 5, the hydraulic pressure extraction device 1
6 is a block-shaped hydraulic pressure take-out body 43 and a connecting body 44.
The mounting bracket 45 is formed of an L-shaped angle member and is attached to the side surface of the clutch housing 3 via a bolt 46, and the hydraulic extractor 43 is mounted on the mounting bracket 45. It is mounted and removably attached with a bolt 47, and is provided near a dividing position 48 between the clutch housing 3 and the transmission case 4.

The hydraulic pressure extraction body 43 has an L-shaped suction passage 49 extending from the front surface to the side surface, and an L-shaped suction passage 49 extending from the side surface to the rear surface.
A letter-shaped discharge flow path 50 is formed, and both flow paths 4
9 and 50 are independent of each other, the front pipe 14a of the discharge side oil passage 14 is welded (brazed) connected to the suction passage 49, and the rear pipe 14b is connected to the discharge passage 50.
are detachably connected via pipe joints.

The connecting body 44 is shown as a first connecting body 44A and a second connecting body 44B in FIGS. 3 and 4, and a third connecting body 44C in FIG. In combination with the third connecting bodies 44B, 44C, they are connected to the hydraulic outlet 43 via bolts 51, and the second and third connecting bodies 44B, 44C can each be connected to the hydraulic outlet 43 independently.

The first connecting body 44A is a straight channel 5 that penetrates from side to side.
2, an outflow channel 54 that penetrates from the right side to the bottom surface and has an opening 53 on the bottom surface; and an inflow channel that penetrates from the top surface to the left side, can communicate with the discharge channel 50, and has an opening 55 on the top surface. A passage 56 is formed.

The second connecting body 44B has a central passage 58 formed in the front-rear direction at the center and having an opening 57 on the front surface, and connecting passages 59 and 60 that communicate the central passage 58 with the straight flow passage 52 and the outflow passage 54. A diverter valve 61 is provided at the intersection of the central passage 58 and the connecting passage 59. Note that it is possible to divert the pressure oil from the connecting path 59 to the opening 57 without providing the diverting valve 61.

The openings 53, 55, and 57 serve as hydraulic pressure outlets, and the opening 53 is connected to a feed pipe 24 connected to the loader control valve 23, and the opening 55 is connected to a return pipe 25. Lift cylinder 21 and bucket cylinder 2
2 can be hydraulically controlled, and the opening 57 has a pipe 6 connected to the forward/reverse control valve 41.
2 is connected, and the forward/reverse hydraulic clutch 2
9 and 30 can be hydraulically controlled. The pipes 24, 25, 62 and the openings 53, 55, 57 are connected removably through pipe joints, but may be welded.

In the case of a tractor not equipped with the forward/reverse transmission mechanism 28, the opening 57 of the connecting body 44B is closed with a blind plug, or the connecting body 44C is attached to the connecting body 44A. This connecting body 44C has the same oil passage as the connecting body 44B, but the opening 57 is closed with a blind stopper 63 and no flow dividing valve 61 is provided.

Moreover, when the front loader 17 is not attached, the connection body 44B or 44C is directly attached to the hydraulic pressure take-out body 43.

The connecting bodies 44A and 44B form a hydraulic pressure take-off oil passage 65 through which the pressure oil in the discharge side oil passage 14 passes to the hydraulic working part, or branches and supplies the hydraulic oil to the hydraulic working part.

The hydraulic pressure extraction device 16 configured as described above is
A hydraulic extraction body 43 in which a suction passage 49 and a discharge passage 50 communicating with the discharge side oil passage 14 are formed, and a first hydraulic working part (forward/reverse hydraulic Clutch 29, 30 etc.)
The suction oil passage 49 is connected to the suction oil passage 49 to supply pressure oil.
and a hydraulic pressure extraction oil passage 58 that communicates with the discharge oil passage 50.
The second connection body (lid connection body) 44B is formed with
and an outflow passage 54 and a discharge passage 50 connected to the second hydraulic working part (lift cylinder 21, bucket cylinder 22, etc.) and communicating with the suction oil passage 49 on the circumference (upper and lower surfaces) to supply pressure oil. Inflow channel 5 communicating with
6, and is provided with a first connecting body (middle connecting body) 44A that is interposed between the hydraulic extracting body 43 and the lid connecting body 44B and is fastened to the hydraulic extracting body 43 together with the lid connecting body 44B. ing. Since the hydraulic outlet 43 and the connecting bodies 44A and 44B can be separated, even if the pipes are connected to each other during disassembly and assembly, the pipes will not crack due to their weight. 44A, 44B, 44C
Can be used in combination depending on the required work. Furthermore, although it is possible to directly attach the hydraulic outlet 43 to the vehicle body 5, disassembling and reassembling work is easier if it is attached via the mounting bracket 45, and cracks in the pipe of the discharge side oil passage 14 can be avoided. It can also be prevented. In addition, when the hydraulic pressure extraction device 16 is arranged near the dividing position between the engine 2 and the clutch housing 3, or when the forward/reverse control valve 41 is provided on the transmission case 4, it is located at the dividing position 48.
It may also be provided on the side surface of the nearby mission case 4.

According to the present invention described in detail above, the discharge side oil passage 14
The hydraulic pressure take-out device 16 located in the middle of the vehicle body 5
Since it is installed near the dividing position 48 of the vehicle body 5, the distance from the hydraulic working part of the front work machine 17 or the hydraulic working part of the central part of the tractor is short, and piping such as hoses can be shortened and inexpensive. When disassembling and assembling, it is only necessary to connect and disconnect the pipe 14b that forms the discharge side oil passage 14 with respect to the hydraulic pressure extraction device 16, so the structure allows the pipe to be connected and disconnected at a different position from the conventional hydraulic pressure extraction device. Disassembly and reassembly work is facilitated, and the discharge side oil passage 1
4 can also be formed at low cost. In addition, the hydraulic extraction device 1
6 allows the middle connecting body 44A to be interposed between the hydraulic outlet body 43 and the lid connecting body 44B, so if the number of hydraulic working parts increases or decreases, the number of hydraulic outlet bodies can be easily increased or decreased accordingly. Yes, the middle connecting body 44
A can be easily attached and detached.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is an overall side view, Fig. 2 is an explanatory diagram of a hydraulic circuit, Fig. 3 is a cross-sectional plan view of a hydraulic pressure extraction device, and Fig. 4 is a cross-sectional view of Fig. 3. 5 is a cross-sectional plan view showing one of the connecting bodies. 2...Engine, 3...Clutch housing,
4...Mission case, 5...Vehicle body, 7...Hydraulic system, 10...Hydraulic circuit, 11...Hydraulic pump, 14...Discharge side oil path, 16...Hydraulic pressure extraction device, 43...Hydraulic pressure extraction Body, 44... Connecting body, 4
8...Divided position, 49...Suction flow path, 50...Discharge flow path, 65...Hydraulic pressure extraction oil path.

Claims (1)

[Claims for Utility Model Registration] A vehicle body 5 is formed by directly connecting an engine 2, a clutch housing 3, and a transmission case 4 so that they can be separated into the front and rear, and a hydraulic pump 1 provided on the side of the engine 2.
A hydraulic circuit 10 is formed for supplying pressure oil from 1 to a hydraulic device 7 provided at the rear upper part of the transmission case 4 through a discharge side oil passage 14, and a hydraulic circuit 10 is formed in the middle of the discharge side oil passage 14 near the vehicle body division position 48. A hydraulic pressure extraction device 16 mounted on the hydraulic pressure extraction device 1 is arranged.
6 is a suction flow path 49 communicating with the discharge side oil path 14;
A hydraulic extraction body 43 in which a discharge passage 50 and a discharge passage 50 are formed.
A hydraulic extraction oil passage is formed which can be directly attached to this oil pressure extraction body 43 and which is connected to the first hydraulic working section and communicates with the suction oil passage 49 and the discharge oil passage 50 to supply pressure oil. In the hydraulic pressure extraction circuit for a tractor that is equipped with a lid connection body 44B, the hydraulic pressure extraction device 16 has a suction oil passage 49 on its periphery in order to be connected to the second hydraulic working part and supply pressure oil.
It has an outflow passage 54 communicating with the discharge passage 50 and an inflow passage 56 communicating with the discharge passage 50, and is interposed between the hydraulic pressure extraction body 43 and the lid connection body 44B, and is connected to the hydraulic pressure extraction body 43 in common with the lid connection body 44B. Middle connecting body 4 to be tightened
A hydraulic pressure extraction circuit for a tractor, characterized in that it is equipped with 4A.