JP2570323Y2 - Operating device for steering mechanism - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for operating a side clutch and a side brake of a steering device using a hydraulic circuit of a hydraulic clutch type transmission.

[0002]

2. Description of the Related Art Conventionally, there has been known a technique in which a gear is shifted by using a hydraulic clutch type transmission, and a side clutch and a side brake are operated by pressure oil to perform steering. For example, Japanese Utility Model Application Laid-Open No. 61-69548 and Japanese Utility Model Application
It is like the technique of JP-A-3-89712.

[0003]

In such prior art, pressure oil is supplied to a hydraulic clutch type transmission and a side clutch and a side brake by a dedicated hydraulic pump. Are installed in parallel, so that the load on the engine increases and space is required, and the number of parts such as piping increases,
It was also necessary to construct an oil passage, which was a high cost factor.

[0004]

The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described. A hydraulically operated steering mechanism consisting of a side clutch that can cut off transmission of power from the hydraulic clutch type transmission to the left and right traveling devices independently on the left and right, and a side brake that brakes the traveling device on the power cutoff side in transmission of a working vehicle that, the discharge side of the hydraulic pump P of the hydraulic clutch transmission arranged delay relief valve 36 connected to the primary side, the delay relief valve 3
6 , a hydraulic operating circuit for a side clutch is connected to the secondary side, and a hydraulic operating circuit for a side brake is further connected to the primary side of the delay relief valve 36. The hydraulic operating circuit for the side brake includes A sequence valve 33 is provided for enabling the side brake after the steering control valve disposed in the hydraulic operating circuit of the clutch is switched, and the operating hydraulic pressure of the side brake is increased in conjunction with the switching operation of the steering control valve 39 . A variable pressure reducing valve 34 is provided.

[0005]

With such a configuration, the fluctuation of the hydraulic pressure at the time of shifting of the hydraulic clutch type transmission is suppressed by the delay relief valve, and when the side clutch lever is turned to one side to turn, the control valve is switched. By operating the hydraulic side clutch to cut off the transmission of power, at the same time, the sequence valve is switched from the pilot oil passage, the switching valve on the turning direction side is also switched, and the side brake is operated, so that smooth turning can be performed.

[0006]

Next, an embodiment will be described. FIG. 1 is a skeleton diagram of a transmission case, and FIG. 2 is a hydraulic circuit diagram of the operating device of the present invention. 1, the input shaft 2 is laid horizontally on the upper part of the transmission case 1, an input pulley 3 is fixedly mounted on one end of the input shaft 2 outside the transmission case 1, and the hydraulic pump P is mounted on the other end. The loose fitting gear 4 and the sliding gear 5 are externally fitted on the input shaft 2 in the transmission case 1, and the loose fitting gear 4 is
The sliding gear 5 is always engaged with the gear 7 fixed above, and the sliding gear 5 is slid by the rotation of the auxiliary transmission lever, and the tooth portion 4a of the loose fitting gear 4 is rotated.
And the gears 8 and 9 on the auxiliary transmission shaft 6 are selectively meshed with each other to enable the auxiliary transmission.

The gear 9 on the auxiliary transmission shaft 6 is further provided with a transmission single shaft 1
The gear 13 on the auxiliary transmission shaft 6 meshes with the gear 13 loosely fitted on the transmission single shaft 11, and meshes with the gear 13 loosely fitted on the transmission 1 and the gear 15 loosely fitted on the transmission double shaft 12. Is engaged with the gear 16 which is loosely fitted on the transmission double shaft 12. A first-speed hydraulic clutch F1 is interposed between the transmission single shaft 11 and the gear 14, a second-speed hydraulic clutch F2 is interposed between the transmission single shaft 11 and the gear 13, and a one-speed hydraulic clutch F2 is interposed between the transmission single shaft 11 and the gear 15. A third-speed hydraulic clutch F3 is interposed between the two gears, and a reverse-speed hydraulic clutch R1 is interposed between the two-speed shift shaft 12 and the gear 16, thereby constituting a hydraulic clutch type transmission.

The gear 1 formed at the center of the transmission shaft 11
7, a gear 18 formed at the center of the transmission two shaft 12 meshes with a gear 20 fixed on the side clutch shaft 19, and a brake drum 22 is fixed at the end of the transmission two shaft 12 to constitute a parking brake. ing. Hydraulic side clutches SCL / SCR are formed between both side surfaces of the gear 20 and the gears 23L / 23R loosely fitted on the side clutch shaft 19, and the gear 2
3L / 23R meshes with gears 24aL / 24aR loosely fitted on the side brake shaft 21, and the gears 24aL / 24a
Hydraulic side brake S between R and side brake shaft 21
BL and SBR are formed, and the gears 24bL and 24bR loosely fitted on the side brake shaft 21 mesh with the gears 32L and 32R on the axles 31L and 31R, and the axles 31L and 31R.
Crawlers or running wheels can be driven by fixing drive sprockets or the like at both ends.

The hydraulic clutches F1, F2, F
The 3 · R1, the hydraulic side clutches SCL / SCR, and the hydraulic side brakes SBL / SBR are connected as in the hydraulic circuit shown in FIG. That is, the pressure oil from the hydraulic pump P is branched, and one of the pressure oils can be supplied to the hydraulic clutches F1, F2, F3, and R1 via the switching valve 30,
By switching the switching valve 30, the oil can be selectively supplied so that the power can be disconnected and connected, so that the speed can be changed. The other of the hydraulic oil from the hydraulic pump P is hydraulically transmitted through the delay relief valve 36. The oil is supplied to the side clutch, and the delay relief valve 36 is connected to the hydraulic clutch F1.
When the F2, F3 and R1 are actuated, the pressure is reduced so that no shock occurs. A steering control valve 39 is connected to the secondary side of the delay relief valve 36, and the steering control valve 39 is connected. Is an electromagnetic valve, and is a switch 4 that is turned on / off by turning the side clutch lever 43.
It is switched by 4L / 44R.

Between the output ports A and B of the steering control valve 39 and the hydraulic side clutches SCL and SCR, oil passages 45L and 4L are provided.
5R, a shuttle switching type pressure regulating valve 40 is provided between the oil passages 45L and 45R for setting the operation of the hydraulic side clutches SCL and SCR so as to be able to operate even at a low pressure. A sequence valve 33 is connected to the primary side of the delay relief valve 36, and a variable pressure reducing valve 34 and a switching valve 3 are connected in series with the sequence valve 33.
5. The hydraulic side brakes SBL / SBR are connected, the switching valve 35 is a control valve that is switched by pilot oil pressure, and the pilot oil passages 46L and 46R are connected to the oil passages 4L and 46R.
5L and 45R are connected to the oil chamber side on which the spools of the switching valve 35 and the sequence valve 33 slide, and the pilot pressure of the switching valve 35 is
The sequence valve 33 is linked to the side clutch lever 43 via a wire or the like. Reference numeral 42 denotes a low-pressure relief valve for setting a lubricating oil pressure.

In such a configuration, the hydraulic oil from the hydraulic pump P rotates the shift lever to switch the switching valve 30 to change the hydraulic clutches F1, F2, F3, and R1 on the shift single shaft 11 and the shift double shaft 12. Is selected and the oil is fed, one of them is operated, and the clutch is brought into contact to perform a shift. The hydraulic pressure for operating this hydraulic clutch is compensated by the delay relief valve 36,
When the delay relief valve 36 is opened, the pressure oil on the secondary side is sent to the steering control valve 39.

Here, when the side clutch lever 43 is tilted to the left, for example, the steering control valve 39 is switched, the oil supply port is connected to the output port A, and oil flows through the oil passage 45L and the pressure regulating valve 4
Thus, the hydraulic pressure is adjusted to 0 to operate the hydraulic side clutch SCL, the transmission of power from the gear 20 to the gear 23L is cut off, and the aircraft turns to the left. Then, the sequence valve 33 is opened from the pilot oil passage 46L, and the switching valve 35 is also switched at the same time, and the pressure oil is supplied from the primary side of the delay relief valve 36 to the sequence valve 33, the variable pressure reducing valve 34,
The hydraulic side brake SBL is actuated via the switching valve 35, and the axle 31L is braked to enable reliable turning. That is, since the primary side of the delay relief valve 36 is used for the brake pressure, a high pressure is obtained,
Only when the brake is turned, the relief pressure of the pressure regulating valve 40 is turned ON on the primary side, so that a high brake braking force can be obtained. When the brake is turned, the axle torque increases, which is advantageous, and at the same time, the clutch capacity is also increased. is there. At this time, the variable pressure reducing valve 34 opens and closes with a pressure proportional to the amount of rotation of the side clutch lever 43 so that the braking force of the hydraulic side brake can be adjusted. Conversely, when the side clutch lever 43 is rotated rightward, the same operation is performed.

[0013]

[Effects of the Invention] The present invention is constructed as described above, and has the following effects. First, the hydraulic oil from the hydraulic pump P is supplied to a plurality of hydraulic clutches.
One of the switch devices is selected and lubricated.
The hydraulic clutch type transmission is
The hydraulic pressure for operation is controlled by the delay relief valve 36.
And the delay relief valve 36 is opened.
Then, the pressure oil on the secondary side is sent to the steering control valve 39,
Used as hydraulic oil for hydraulic side clutch
You. And, the conventional technology of Japanese Utility Model Laid-Open No. 63-89712
In the technology described in the publication, the hydraulic side brake actuation
Hydraulic pump, hydraulic transmission and hydraulic side clutch
And two hydraulic pumps are provided.
Pressure on the primary side of the hydraulic pump for the device and hydraulic side clutch
Oil is supplied to the cylinder of the hydraulic side clutch to
The operation of the switching valve of the hydraulic side clutch is
The complex structure of using pressurized oil from a hydraulic pump
It has become. On the other hand, as in the present invention,
Hydraulic transmission with one hydraulic pump
The primary side of the delay relief valve 36 for
Used for brakes, and the hydraulic oil on the secondary side
Pressure for one hydraulic pump P
Hydraulic side brake and hydraulic side clutch
It is necessary to operate three devices of the hydraulic clutch type transmission.
The configuration of the oil passage for pressure oil is not complicated.
Simplifies the processing of oil passages and reduces manufacturing costs.
You can do it. Secondly, since the hydraulic pump of the hydraulic clutch type transmission is connected to the primary side of the delay relief valve 36, and also to the primary side, the hydraulic operating circuit of the side brake is connected. It could be used for the side brake as it was, and the braking force of the brake could be secured. Third, when the operating oil pressure of the side brake is taken out from the primary side of the delay relief valve 36, the pressure is too high. The brake can be braked. Fourth, since the side valve is provided with a sequence valve that is operated via the pilot oil passage from the side clutch to operate the side brake, it is possible to sequentially and reliably operate from the side clutch to the side brake. It is. Fifth, since a variable pressure reducing valve that is operated in conjunction with the side clutch lever is connected in series with the sequence valve, the side brake can be operated at low pressure, and the braking force is adjusted according to the amount of rotation of the side clutch lever. I was able to turn with good feeling.

[Brief description of the drawings]

FIG. 1 is a skeleton diagram of a transmission case.

FIG. 2 is a hydraulic circuit diagram of the operating device of the present invention.

[Explanation of symbols]

 P Hydraulic pump F1, F2, F3, R1 Hydraulic clutch SCL / SCR Side clutch SBL / SBR Side brake 30 Switching valve 33 Sequence valve 34 Variable pressure reducing valve 35 Switching valve 36 Delay relief valve 39 Steering control valve

Claims (1)

(57) [Scope of request for utility model registration] 1. A steering mechanism comprising a side clutch capable of independently interrupting transmission of power from a hydraulic clutch type transmission to left and right traveling devices and a side brake for braking the traveling device on the power interruption side. in transmission of a working vehicle configured to hydraulic operation type, a discharge side of the hydraulic pump P of the hydraulic clutch transmission arranged delay relief valve 36 connected to the primary side, the secondary side of the delay relief valve 36, the side The hydraulic operation circuit of the clutch is connected, and on the primary side of the delay relief valve 36 ,
Further, a hydraulic operating circuit for the side brake is connected, and the hydraulic operating circuit for the side brake is provided with a sequence valve 33 that can operate the side brake after switching the steering control valve disposed in the hydraulic operating circuit for the side clutch. An operating device for a steering mechanism, comprising a variable pressure reducing valve 34 for increasing the operating oil pressure of a side brake in conjunction with the switching operation of the steering control valve 39 .