JP2554335Y2 - Tractor valve case mounting structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure of a valve case containing a hydraulic valve for controlling a hydraulic lift for lifting and lowering a working machine.

[0002]

2. Description of the Related Art Conventionally, hydraulic cases and tractors for tractors have been used.
Since the technology related to Linder's technology is known,
is there. For example, Japanese Utility Model Laid-Open No. 57-37022 and
JP-A-63-34774 and JP-A-2-54687.
And Japanese Patent Application Laid-Open No. 62-83768.
It is as follows. Usually, a hydraulic case is mounted on the transmission case of the tractor, and as shown in FIG. 8, a turning shaft 6 is laid horizontally on a rear portion of the hydraulic case 15, and lift arms are provided at both ends of the turning shaft 6. A cylinder 11 'is installed in a hydraulic case 15 for rotating the lift arm by being fixed so that the work machine can be raised and lowered, and a hydraulic valve 16 and a control valve for control are provided between the cylinder 11' and the transmission case. Links and the like were provided.

[0003]

However, with such a layout, since the rear portion of the seat is located above the pivot shaft 6 of the hydraulic case, the lowering of the seat is restricted, and the pivoting of the hydraulic case is restricted. Since the shaft portion protrudes, a dead space A is generated between immediately below the seat and the hydraulic case. In addition, since the hydraulic valve 16 is provided in the lower portion of the hydraulic case, the dimension between the PTO shaft and the upper end of the hydraulic case cannot be reduced as shown in FIG. 8, the seat cannot be lowered, and the center of gravity cannot be reduced. Was higher. Also,
Most of the causes of failures in hydraulic valves are caused by dirt clogging, so when replacing or cleaning the hydraulic valve, the hydraulic case must be removed from the transmission case before the hydraulic valve can be removed. It was troublesome work.

[0004]

The present invention is configured as follows in order to solve such a problem.
According to claim 1, a tractor mission case 1
A cylinder 10 for rotating the lift arm 7 is arranged at the top
Then, the hydraulic case 1c supporting the cylinder 10 is
And the hydraulic case part 1
c, a front support 1 supporting the front of the cylinder 10
a and a rear support portion 1b for supporting the rear portion of the cylinder 10.
And the rear support portion 1b is provided inward from the hydraulic case portion 1c.
Configuration in which the insertion hole of the cylinder 10 is provided in the wall protruding from the part
And a hydraulic cable between the front support portion 1a and the rear support portion 1b.
On the upper surface of the base 1c, a valve
The case 12 is provided. In claim 2,
Lift arm 7 at the top of the tractor's mission case 1
Is disposed, and the cylinder 10 is rotated.
The hydraulic case part 1c supporting the
The hydraulic case part 1c has a cylinder 1
Front support 1a for supporting the front part of the cylinder 10;
And a rear support portion 1b for supporting a rear portion of the vehicle.
1b is mounted on a wall projecting inward from the hydraulic case 1c.
And the front support portion 1 is provided.
a on the side of the hydraulic case 1c between the rear support 1b and
A valve case 12 'for controlling lifting and lowering of a working machine is provided.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The problem to be solved by the present invention and the means for solving it are as described above, and the configuration of the embodiment shown in the accompanying drawings will be described. 1 is a partial cross-sectional view of a side of a transmission case, FIG. 2 is a side cross-sectional view of a hydraulic case, FIG. 3 is a rear view of the same, FIG. 4 is a side view of a transmission case showing an embodiment in which a hydraulic valve is attached to the side, and FIG. FIG. 6 is a side sectional view showing a supporting portion of the cylinder, and FIG.
It is XX sectional drawing in. The transmission case 1 disposed below the seat 2 of the tractor has an input shaft and gears for shifting in the lower part, and supports the rear wheel axle 3 on the side,
The PTO shaft 4 protrudes from the rear surface. A hitch 5 for pivotally supporting the top link is fixedly mounted on the upper rear surface of the transmission case 1, and a rotary shaft 6 is laid horizontally with a front portion of the hitch 5 as a hydraulic case portion 1 c. Lift arms 7, 7 are fixedly provided outside the case 1, and a turning arm 8 is fixedly provided in the hydraulic case portion 1c.
Has a rod 9 fitted at the lower end, and the other end of the rod 9 is fitted to the piston 11.

The piston 11 is inserted into a cylinder 10, which is supported at the front and rear. That is, conventionally, as shown in FIG.
Because only the front part was supported by the hydraulic case 15, oil leakage occurred from the seal part when an eccentric load was applied. Therefore, in this embodiment, as shown in FIGS. 6 and 7, the front and rear portions of the cylinder 10 are securely supported by the support portions 1 a and 1 b protruding from the transmission case 1, and are integrally formed with the transmission case 1. Because it is composed,
Since the dimensional accuracy is good and the front cover 13 is assembled from the front, assembly can be easily performed. The front cover 13 that covers the front surface of the transmission case 1 integrally forms the cylinder head of the cylinder 10, is more compact than the conventional case provided separately, and reduces the number of parts and cost. The cylinder head is provided with an adjustment valve handle 24 which can adjust the lowering speed of the lift arm 7 and can also lock it.

The valve case 12, which is a main part of the present invention, is disposed on the upper surface of the transmission case 1. That is, conventionally, if the valve case 12 'is located below the cylinder 10 as shown in FIG.
Dead space is created. In the present invention, the cylinder 10 is disposed on the upper surface in front of the rotary shaft 6 of the transmission case 1 integrated with the hydraulic case, and the space in which the hydraulic valve is disposed is eliminated, and the cylinder 10 is positioned lower. The seat 2 to be arranged is also arranged at a lower position. A hydraulic valve 16 is provided at a front portion inside the valve case 12, and a lift lever 17 for switching the hydraulic valve 16 is projected from a rear side surface of the valve case 12. When the lift lever 17 is rotated, the lift lever 17 The rotating arm 19 provided continuously is rotated to push the spool of the hydraulic valve 16 for switching. Further, a link (not shown) is interposed between the lift arm 7 and the hydraulic valve 16 so that the tillage depth can be controlled. The link is operated by feedback from the rear cover (sensor) to keep the tillage depth constant. It is also possible to control.

As shown in FIGS. 4 and 5, the valve case can be disposed on the side of the hydraulic case 1c above the transmission case 1. In this case, the fender 22 and the hydraulic case 1c As a result, the cylinder 10 and the seat 2 can be disposed at a low position as described above, and the wasteful space can be effectively used.

[0009]

According to the present invention, the following effects can be obtained. First, the hydraulic case part 1
c, a front support 1 supporting the front of the cylinder 10
a and a rear support portion 1b for supporting the rear portion of the cylinder 10.
And the rear support portion 1b is provided inward from the hydraulic case portion 1c.
Configuration in which the insertion hole of the cylinder 10 is provided in the wall protruding from the part
So that the cylinder 10 supports the front and rear
Can be reliably supported by the portion 1a and the rear support portion 1b.
You. Also, the dimensional accuracy is improved, and the cylinder 10 is moved forward.
It can be inserted into the support part 1a and the rear support part 1b from the front.
Thus, assembly can be easily performed. Second, the front support
Upper surface of hydraulic case portion 1c between 1a and rear support portion 1b
Or, because the valve case is located on the side,
Oil path between the valve in the cylinder and the cylinder 10
And the mission case 1
It is possible to drill an oil passage in the thick part,
There is no longer any need to do any lingering.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a side view of a transmission case.

FIG. 2 is a side sectional view of a hydraulic case part.

FIG. 3 is a rear view of the same.

FIG. 4 is a side view of a transmission case showing an embodiment in which a hydraulic valve is provided on a side surface.

FIG. 5 is a rear view of the same.

FIG. 6 is a side sectional view showing a support portion of the cylinder.

FIG. 7 is a hydraulic circuit diagram which is a sectional view taken along line XX in FIG.

FIG. 8 is a side sectional view of a conventional transmission case.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transmission case 1c Hydraulic case part 2 Seats 10 Cylinder 12 Valve case

Claims (2)

(57) [Scope of request for utility model registration] 1. An upper part of a transmission case 1 of a tractor.
A cylinder 10 for rotating the lift arm 7 is arranged.
Mission of hydraulic case 1c supporting cylinder 10
The hydraulic case part 1c is formed integrally with the hydraulic case part 1c.
Is a front support 1a for supporting the front of the cylinder 10.
And the rear support portion 1b supporting the rear portion of the cylinder 10
The rear support portion 1b is provided inside from the hydraulic case portion 1c.
A configuration in which an insertion hole for the cylinder 10 is provided in a wall protruding from
And a hydraulic cable between the front support 1a and the rear support 1b.
A valve cable for controlling the lifting and lowering of the working machine is provided on the upper surface of the
The mounting structure of the valve case of the tractor, wherein the tractor 12 is disposed . 2. An upper part of the tractor's transmission case 1
A cylinder 10 for rotating the lift arm 7 is arranged.
Mission of hydraulic case 1c supporting cylinder 10
The hydraulic case part 1c is formed integrally with the hydraulic case part 1c.
Is a front support 1a for supporting the front of the cylinder 10.
And the rear support portion 1b supporting the rear portion of the cylinder 10
The rear support portion 1b is provided inside from the hydraulic case portion 1c.
A configuration in which an insertion hole for the cylinder 10 is provided in a wall protruding from
And a hydraulic cable between the front support 1a and the rear support 1b.
A valve cable for controlling the lifting and lowering of the working machine
The mounting structure of the valve case of the tractor, wherein the tractor 12 'is disposed .