JPS6087702A - Hydraulic controller of tractor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

The present invention relates to a hydraulic control device for a tractor. Conventionally, the hydraulic pressure 1iI11 control circuit that controls the left and right posture of the rotary plowing device to a certain level, for example, a horizontal posture, and also controls the designated 72: plowing depth to a horizontal posture, is controlled from the left and right posture control cylinder. A lift cylinder for raising and lowering the discharged oil YO-Tari tilling device (two grooves supplying the groove,
When the threatening pressure based on the movement resistance f2 of the lift cylinder and its piston acts on the left and right posture l11g @ the discharge side C of the cylinder, the movement of the piston of the left and right posture control cylinder of the engine is slowed down, and the a-Tari tilling device is Left and right posture 1BIl (
4 The movement is slow (9 III control is also incomplete). Otsu's invention in the 1970s was a movement delay RTV in left and right posture control.
In order to eliminate this problem, the pressure oil supplied to the lift cylinder is separated from the pressure oil to the left and right attitude control cylinders, and the first technical means is taken as the first invention. In other words, the pressure oil of the oil pump Alpha? 1 a- by diversion valve q
The left and right attitude control cylinder (71) of the rotary tilling device (21)
A return oil passage c34 is provided at the mouth of the attitude control valve rT7 to divert the oil discharged from the left and right attitude control cylinders (7) to the lift cylinder α button 2 of the lift cylinder
2: This is the configuration of the hydraulic control device of the tractor. As a result of this, the first invention can obtain the following technical effects. That is, pressure oil is independently supplied to the lift cylinder α → to the left and right position 111 Jil cylinder (70) with the four ports of the Fi1 flow valve behind, and the oil discharged from the pressure cylinder (η) is supplied to the return oil path. (To) causes tank C2 to return to ζ2.The discharge operation is quick, there is no need for the left and right attitude control cylinder (7) to move C2, and left and right attitude control is performed accurately with good followability. The supply and discharge of pressure oil to the lift cylinder (14?) has also become faster, and 1i# depth control has also become more accurate.Next, 1!# depth automatic control ta1 (:l:, rt, manual operation It is more convenient for feedback to use an electromagnetically actuated control valve than a type-type elevating control valve. Generally, valves are used, and in the case of oil pumps, the pressure oil of the oil pump is used to supply a predetermined flow of 1lt to the lift control valve and the electromagnetically actuated valve, respectively, to control the lift. When the valve does not require pressure oil, the circuit is configured to return the pressure oil to the tank that should originally supply the pressure oil to both valves, so the excess oil pressure is wasted. 0 70 and the second invention (in 2, the elevator 111r (a11
The surplus oil in the valve is also supplied to the electromagnetically actuated control valve without wasting it.
Attitude control valve Elevation control: JPuψ (two-way flow,
rt when operating the lift control valve in the raised position. The oil spilled from each of the above diversion valves 4 and 11-valve haze. This is the configuration of a hydraulic control system for a tractor, which is configured to supply water via a pressure regulating valve to an electromagnetically actuated control valve for automatic control of plowing depth. With this configuration, C's second invention was able to achieve the first technical effect. That is, except when operating the lift control valve in the 〇 raise position. The leaked oil from the flow divider valve and the attitude control valve flB is 0 to the pressure regulating valve.
1'lk: All electromagnetically actuated control valves (goods) (2) are supplied through, so when pressure oil is required to the lift control valve (- to the lift cylinder), the pressure oil is not wasted and is Actuated control valves - 2 and 2 are used.Also, the cost can be reduced by omitting the equipment of the flow divider valve for dividing the flow between the lift control valve (to) and the electromagnetically actuated TW control valve. I was able to make it a reality. Next, when using a magnetically actuated control valve, pressure oil leakage from the valve section becomes a problem, especially the lower valve that discharges the pressure oil in the lift cylinder according to the command value, and the lower valve that discharges the pressure oil in accordance with the command value, and the When lowering the a-tall equipment that has been hoisted to the ground. The descending speed control valve throttles the discharge of the pressure oil in the 177 cylinder so that the jaws touch the ground slowly. If the leakage of the valve part is not configured to be small, these valves will be of no use at all. Therefore, in the invention @3 and the fourth invention, such leakage prevention is In general, the check valve is installed to prevent pressure oil from leaking in the lift cylinder when the oil pump is turned on and off, and the valve is turned into the reverse L) + state or the state where backflow is possible ( In order to take advantage of the advanced leakage prevention function of the predetermined pre-valve with two switching, I purchased the Technological Fishing Technique VI by Jin Nimehisa.In other words, the third invention is the oil pump a An attitude control valve tlfi that supplies and discharges pressure oil to the left and right attitude control cylinders 1 of the rotary cell @ device 1t121 using a diversion valve, and an elevation control valve that supplies and discharges pressure oil to the 0 and 2 lift cylinders of the a-tary cultivating device (2). 136), and when the elevation control valve αG) is operated in the raised position, the flow is divided into the above-mentioned diversion valve wI and attitude control valve 1 (2).
The respective spilled oil is thrown through the pressure regulating valve (to) to be supplied to the electromagnetically actuated control valve I21) for automatic tillage depth control. A check valve that is bifurcated between the lift cylinder 0→ and the elevation control valve αG) to control the oil discharged from the lift cylinder 0→, and a check valve (to) in the non-return state, or. This is a hydraulic control system for a tractor in which a lower valve tray for the electromagnetically actuated control valve is provided downstream of each of the preceding valves for switching to a state in which backflow is possible. In addition, the fourth invention rt is an a-Tari plowing device (attitude control valve +12 for supplying and discharging the left and right attitude control cylinders (7) of 21) by dividing the pressure oil supply 1 flow valve of the oil pump 0 port, and the a- Tari plowing and drying is divided into (lift cylinder 0 of 23 → (elevating control valve u6 for lifting and discharging), and when the elevating control valve aO) is operated in the raised position, flll is turned off by the above-mentioned diverter valve and then the attitude control valve. (W
The C2 device 7 is connected to the lift cylinder A4 and the lift control valve (To) so as to supply each spilled oil W to the electromagnetically actuated control valve for automatic tillage depth control via the 11 pressure valve (G) 7. Between C
A check valve (to) that should control the oil discharged from the lift cylinder) and a check valve (to) to the non-return state.
Or. Discharge oil 1f from the lift cylinder 04 is placed downstream of each preceding valve (to) for switching to a state where backflow is possible.
This is the configuration of a hydraulic control device for a tractor that is provided with a descending speed control valve that throttles fi. And since C: is configured like this, in the third invention a,
I was able to enjoy the technical effects of 6c. In other words, the pressure oil in the lift cylinder (6) must be removed from the RFT valve (which is installed), and it may be activated violently.
Or non-crop! Preliminary valve for switching to Jh8 state (
7) Since a lowering valve is installed on the downstream side of the lift cylinder 0, the pressure oil from the lift cylinder 0 will leak through the reverse valve (to) and be held at the valve part of the lowering valve (to). There is no longer any need for precision in relation to the current, and the lowering valve is easy to use.
By using this, it was possible to achieve υF deep automatic control with good followability at a small net cost and by eliminating leakage. Next, in the fourth invention, as described above, the lift cylinder 4 is
Since the descending speed control valve mχ is installed downstream of the highly accurate check valve that can prevent the leakage of the pressure oil inside, the leakage from the descending speed control valve m is reduced. The effect of controlling the descending speed ri to a desired gradual value can be obtained by nrt. Next, one embodiment 91 of the present invention will be explained based on the drawings. Fig. 1 shows a tractor (11) and the NZ rotary tilling device (2) connected thereto, and Fig. 2 shows an example of its hydraulic control circuit.
side lift arm

[3] is connected to the lower link (6) on the same side through the lift rod (5), and the lift arm i41 on the other side is connected to the left and right attitude control cylinder (■ and its piston [81) on the same side. For example, air bubbles in a liquid sealed in a transparent tube are connected to the lower links (9), respectively.
-Tari υF Linso @ (moves left and right as 21 tilts to the left or right) Photoelectric type C: Posture detector α that detects
a2 is installed, and the detection operation of this attitude detector α1 controls (
In order to maintain the left-handed rotational posture of the rotary tiller [21] at a constant level, e.g., horizontal C2, by operating the posture control valve, the pressurized oil of the oil pump α4 is activated. It supplies and discharges the left and right attitude control cylinder [η]. Left and right glue 7 to arms (3) (a) r! The lifting piston (5) moves in and out of the lift cylinder) and rotates up and down as one unit, and the pressure oil in the oil pump 0 is controlled by the switching operation of the up/down control valve (to). υF deep return port 1lNlilrt, provided so as to always be in sliding contact with the surface of the cultivated soil tilled by the tiller (b).
For example, it is used as a tiller cover ts# depth sensor, plowing depth designator; specified plowing depth value specified by the barrel (2) so that the above detection υ and depth values match 52, control unit ■rt, electromagnetic actuated type Pressure oil is supplied to and discharged from the lift cylinder by operating the raising valve (2) or lowering valve nv of 11011 Valve Co., Ltd. a-tari tilling device (height of the cultivating body just before it touches the ground after descending from the suspended state = 1% when reached)
A sensor is operated by, for example, a lift arm (40) to detect oil discharged from lift cylinder A4 at a descending speed [111
It is configured so that the above operation of the detector is canceled due to the gradual lowering of the tow arm (41) by I (all valves), and the details of the hydraulic control circuit. The structure is that the pressure oil of the oil bongo is introduced into the diversion valve through the neutral boat of the external hydraulic pressure lI + control valve for operating work equipment such as a 7ci no loader, and the 1-diversion valve is introduced into the outlet behind the diversion port.
il)+281 are connected to oil path - and oil path ■, respectively, and oil path @ supplies pressure oil to the attitude control valve (branch), and oil is supplied via the neutral boat of the attitude control valve (branch). The oil passage C3D, which connects the two roads to Route 6, merges with the oil route ■ to form a wave route (to), and the oil route (to) is the ascending I! ! It is connected to electromagnetically actuated control valves 11 and 11 via a control valve αφ and a pressure regulating valve (to), respectively. Then, the diversion valve q sends a certain amount of pressure oil, which accounts for the majority of the pressure oil that enters from the operation j of its spool (therefore, from the external hydraulic pressure 1IIIllall valve), to the oil passage -1, and the remaining oil quantity to the oil passage -1. The left and right posture is 11111 cylinders (
The discharged oil in step 7) is discharged from the exhaust control valve 1 (2) to the tank (T1) behind the return oil path. The pressure oil in the lift cylinder is prevented from leaking by the reverse valve (to) and the preceding valve (01), and the preceding valve CiV is kept in position 2 and the oil bong haze is In the stopped state, the lift III instantaneous valve (to) scream in Fig. 2 (lower position movement; even if it moves, it does not move freely (oil passage); it is made by pressure oil). Pressure oil ri in the lift cylinder 04 enters the valve chamber (35a) of the reverse valve (to) from the oil passage and layer, and also flows from the oil passage Gη to the upper bow (36 m) of the preceding valve (to), the oil passage (to), then the valve chamber (
35b), so the valve (35d) closes the oil passage toward the lift control valve aφ by the action of the valve spring (35c). (2) Pressure oil in the oil passage (to) will be lowered from 16 m to the lowering bow of the lift!I control valve (to)). The leading valve 01C is supplied through the passage - and the leading valve g19t7@2 is switched to the lower position shown in the figure, so the pressure oil in the valve chamber (ASB) is lowered to the lower boat (through 3 (IB) to the tank C'RZ) & discharged. San...
Pressure line rt oil passage valve in lift cylinder o casting! (35,
a Oil input y6CII, lowering bow of elevation control valve 4φ) (16
25a) (when operating the height sensor) or non-L5 boat (zsb) v = 2” c fi / (Tm) 4 : To be discharged C2 9. Pressure oil rj in the back pressure chamber of the 1g pressure valve (to), via the lowering boat (1 shaft).Tank (T1)
Since the pressure is discharged to
This is the valve that supplies pressure oil to the electromagnetically actuated control valve (b). In addition, C2ri supplies (two-pressure oil to the lift cylinder)
s rise and fall! C: Move the 1J valve valve φ to the raised position. The pressure oil in the oil path (to) is supplied to the lifting boat (
16b) from the oil passage μml to the back pressure chamber of the pressure regulating valve (to), so the pressure regulating valve (to) is in a closed tt + swing state (9, and the high i pressure oil in the oil passage (to) is raised) Pressure oil will flow into the valve chamber (35a) through the oil passage (to) from (16b), push open valve CB, and supply pressure oil to the lift cylinder 04 from the oil passage (to). Even when the control valve α61Y is moved to the neutral position, the pressure oil in the back pressure chamber of the pressure regulating valve (to) remains at the neutral position (16e) P
Since the water is discharged to the tank (Ts), fJ4 pressure valve 01t
1kl of pressure oil in oil passage (2) is in communication state! Magnetically actuated 111! This is to be supplied to the goben■. Then, when the oil pump is stopped, if the preceding valve (to) and the elevation control valve α←h are moved to the lower position, the pressure oil in the valve chamber (ssb) is discharged to the lower boat (36b) and then to the tank (T,). Since the valve (35d) is pushed open, the pressure oil in the cylinder 0 and θ passes through the check valve and the lift control α6 and is discharged to the tank (T8 and 2). To perform automatic plowing depth control using the electromagnetic actuated type i1? By energizing or demagnetizing the lunoid, the pressure oil in the oil passage (to) is transferred from the switching valve (6) to the valve (43 and oil passage 1444' to the lift cylinder a) through the pressure regulating valve IA. Alternatively, by the operation of the preceding valve (to) ζ2, the reverse valve (to) ηλ, etc., the pressure oil of the lift cylinder α is lowered by the lowering speed of the lift control valve Q (1) (16a)%. Pressure oil is discharged to the tank (T3) via the control valve (F), and the amount of pressure oil is proportional to the operating time of the upper valve and lower valve μs). Lift cylinder/dummy 4C 2 supply or 1
This is what will be discharged from now on. Part 'C), in the state where the extensions (the upper valve and the lower valve) in Fig. 2 are both demagnetized, the valve chamber (3) of the preceding valve (to)
6c) Pressure oil is supplied from oil path 4 to the lower bow (lower bow) (2) when the lower valve is opened.
3a) through the tank ('ri) < two discharged nb oil passages (
Pressure oil is supplied to the preceding valve ga'Ik via oil passage t4I'r.
: Because Kanji on the left moves. Pressure oil in the valve chamber (35b) of the reverse and valve (to)? (lowering bow) (
36b) Drain the pressure oil into the tank (T2) and into the lift cylinder by pushing open the valve (3sd), z reverse valve (to) and lowering boat (16a) s lowering speed mmm J valve. g＠Please drain it into the tank (T,), and also use the switching valve (9
) The pressure oil in the valve chamber (42a) of the valve chamber (42a) is discharged from the lift valve @ηλ to the tank (Ts), so the switching valve (6) is
2h), the neutral boat (44c) entered the oil channel.9. The lift arm (41 is the one that gradually descends. When the lift valve -) and the lower valve open are both energized to their electromagnetic solenoids, the pressure oil ld from the pressure regulating valve (to) passes through the oil path IAew and lifts up. Since the oil flows into the valve chamber (42a) of one switching valve through the valve @tamera oil passage t47)a', the raised boat (42d) looks into the wave channel (IQ) near the switching valve, and the pressure oil is oil road r43.lifting boat (ts2d
), flows into lift cylinder a4 via oil passage 4, +J7 tor arm (4) rises, and pressure oil from pressure regulating valve (to) flows from oil passage 4 to lift boat (a) of lowering valve -).
23b) ' flows from oil passage 1 into the valve chamber (36c) of the preceding valve (to), and from oil passage @ to the check valve via the pressure oil supply boat (36a) Y of oil passage (b). (to) valve chamber (3
5b), this check valve 0!1 will be switched to the reverse positive state. Then, the detected υF depth value detected by the IF depth sensor (4) will be detected by the υF depth setter CI. When the specified plowing depth value C as specified by , switching valve (turn) raw bean bow) (42c) -
From the raising boat (23b) of the fi wave channel (season. Look into package 0, and the pressure oil of oil channel 00 is a lowering valve @) to oil channel A9? : Via the valve chamber (36c
), so the pressure oil in the oil path (b) is raised.
C36a)s It flows into the valve chamber (35b) of the check valve (to) through the oil passage (to), and the check valve (to) becomes a check valve.
Therefore, the pressure oil in the cylinder 7 is maintained as it is, and the lift arm 41 is also stopped.

[Brief explanation of the drawing]

The figure shows the first example of this invention.
The figure is a perspective view of the tractor and the a-tali square device, and the second figure of the broom is a hydraulic control TG circuit diagram. Code explanation

Claims (1)

[Scope of Claims] (1) - An attitude control valve that supplies and discharges the left attitude control cylinder C2 of the rotary tiller by means of the pressure oil t1 flow valve of the oil pump; A tractor hydraulic control system in which the attitude control valve is provided with an oil path that returns the discharged oil from the left and right attitude control cylinders to the tank. The flow is divided into the posture control valve that supplies and discharges the left and right posture control cylinders of the rotary tiller, and the lift control valve that supplies and discharges the lift cylinder of the rotary tiller.When the lift control valve is operated in the raised position, the pond is Oil spilled from each valve and attitude control valve is supplied to an electromagnetically actuated control valve for automatic tillage depth control via a pressure regulating valve. A posture control valve that supplies and discharges the left stone posture control (2) cylinder of the rotary 1! # case equipment by the pressure oil t1 diversion valve, and a lift II III fil! valve that supplies and discharges the lift cylinder of the 0-tari cultivation device. Divided into, ascending and descending l!
! In addition to when the I control valve is operated in the raised position, the spilled oil from each of the above-mentioned flow divider valve and attitude control valve is provided to be supplied to an electromagnetically actuated control valve for automatic tillage depth control through a pressure regulating valve,
A check valve C2 is installed between the lift cylinder and the lift control valve to control the oil discharged from the lift cylinder. A hydraulic control system for a tractor, wherein a lowering valve of the electromagnetically actuated control valve is provided downstream of each preceding valve IIUI for switching. (4) The pressure oil of the oil pump is transferred to the left and right positions of the rotary tiller using the diversion valve! The flow is divided into the attitude control valve that supplies and discharges to the ill cylinder, and the elevation IQ control valve that supplies and discharges to the lift cylinder of the rotary tiller. Other than when the lift control valve is operated in the raised position, the spilled oil from the above-mentioned diversion valve and the posture valve is supplied via the pressure regulating valve to the electromagnetically actuated control valve 42 for return port movement control. 137) A check valve is installed between the cylinder and the lift lIj control valve to control the oil discharged from the lift cylinder, and the other check valve is placed in the non-return state, or the back flow is A hydraulic control device for a tractor comprising a descending speed control valve for controlling the total amount of oil discharged from a lift cylinder downstream of each preceding valve for switching between two possible states.