US3613798A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic control system for agricultural implements
Assignee: Council of Scientific and Industrial Research
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Filing: 1969-05-06
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Granted: 1971-10-19
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Expires: 1989-05-06
Abstract
Abstract A control mechanism for agricultural implements mounted on three-point linkages in tractors includes a valve mechanism which controls the hydraulic circuit. A single selection and operational control device operates the implements and draft- and position-sensing means act through a cam and lever arrangement for controlling the operation of the valve mechanism which includes two concentrically arranged valve members for regulating the flow of the fluid in the hydraulic circuit.
Inventors
- 👤 Chandra Mohan
- 👤 Gursharan Singh Rihal
- 👤 Balbir Singh Devgun
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:32
CPC Classifications
A; A01; A01B; A01B63/00; A01B63/02; A01B63/10; A01B63/111; A01B63/1117; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/87917; Y10T137/88022
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
232 words
A control mechanism for the regulation of a hydraulic circuit in tractors for controlling the movement and working of mounted implements attached to a three-point linkage, comprising a valve mechanism comprised of at least a first and second control valve controlling the working of the said hydraulic circuit, said second valve disposed within said first control valve, a selection and operational control means for selecting and controlling draft- and position-working of the said implement, a draft-sensIng means operatively connected to said implement, position-sensing means operatively connected to said implement, and a responsive means arranged to receive an actuation movement from said implement through said draft-sensing means and position-sensing means, said responsive means also arranged to receive an actuation from said selection and operational control means, said responsive means comprising a shaft an actuator rotatably mounted on said shaft. a position member rotatably mounted on said shaft, and arranged to be actuated by said position-sensing means, a draft member rotatably mounted on said shaft and arranged to be actuated by said draft-sensing means, said actuator mounted between said draft member and position member and arranged for engagement with either said position member or draft member upon being actuated by said selection and operational control means, and said actuator being arranged to actuate one of said first and second control valves in response to its engagement with either said position member or draft member.
Claim 2
Dependent Claim
232 words
A control mechanism for the regulation of a hydraulic circuit in tractors for controlling the movement and working of mounted implements attached to a three-point linkage, comprising a valve mechanism comprised of at least a first and second control valve controlling the working of the said hydraulic circuit, said second valve disposed within said first control valve, a selection and operational control means for selecting and controlling draft- and position-working of the said implement, a draft-sensIng means operatively connected to said implement, position-sensing means operatively connected to said implement, and a responsive means arranged to receive an actuation movement from said implement through said draft-sensing means and position-sensing means, said responsive means also arranged to receive an actuation from said selection and operational control means, said responsive means comprising a shaft an actuator rotatably mounted on said shaft. a position member rotatably mounted on said shaft, and arranged to be actuated by said position-sensing means, a draft member rotatably mounted on said shaft and arranged to be actuated by said draft-sensing means, said actuator mounted between said draft member and position member and arranged for engagement with either said position member or draft member upon being actuated by said selection and operational control means, and said actuator being arranged to actuate one of said first and second control valves in response to its engagement with either said position member or draft member.
Claim 3
Dependent Claim
14 words
A control mechanism as claimed in claim 1, wherein said actuator comprises a cam.
Claim 4
Dependent Claim
26 words
A control mechanism as claimed in claim 2, wherein said position member comprises a position radial arm, and said draft member comprises a draft radial arm.
Claim 5
Dependent Claim
62 words
A control mechanism as claimed in claim 3, wherein said shaft being formed as a hollow section, a longitudinal slot provided in said shaft, a spring-loaded plunger disposed within said shaft and having an abutting means arranged to travel within said slot, and said abutting means arranged to actuate said cam upon said plunger being actuated by said selection and control means.
Claim 6
Dependent Claim
66 words
A control mechanism as claimed in claim 4, wherein two first pins extending from said cam on the side thereof of the said draft radial arm and one second pin extending from said cam on the side thereof said position radial arm, and spring means urging said cam toward said draft radial arm to maintain engagement of one said first pin on said draft radial arm.
Claim 7
Dependent Claim
132 words
A control mechanism as claimed in claim 5, wherein said position radial arm having a slot therein, said abutting means effects the actuation of said cam away from the said draft radial arm into engagement with the position radial arm through said second pin on said cam when said second pin and the slot on said position radial arm are opposite each other, said spring-loaded plunger allowing give in the event the slot in said position radial arm is not opposite said second pin at the moment of actuation and said second pin coming up against the side of said position radial arm, said spring-loaded plunger effecting subsequent engagement of said second pin with the slot when said position radial arm rotates to bring the slot into line with said second pin.
Claim 8
Dependent Claim
82 words
A control mechanism as claimed in claim 6, wherein the other said first pin on the said control cam projecting towards said draft radial arm being arranged in the path of the draft radial arm irrespective of the axial position of the said cam, the other said first pin being arranged to actuate said cam when working in automatic position control and the actual draft forces on said implement exceed said draft valve corresponding to the set position by a predetermined amount.
Claim 9
Dependent Claim
45 words
A control mechanism as claimed in claim 1, wherein said valve mechanism includes a third valve operative during overload on said implement and capable of receiving an actuation from said responsive means, and said selection and operational means controlling the actuation of said third valve.
Claim 10
Dependent Claim
31 words
A control mechanism as claimed in claim 1, wherein the said selection and operational control means include a single operating lever and a plurality of cams on said single operating lever.
Claim 11
Dependent Claim
35 words
A control mechanism as claimed in claim 8, wherein said third valve comprising a spool valve located in said hydraulic circuit for selectively releasing the pressure of said hydraulic circuit during overloads in said implement.
Claim 12
Dependent Claim
34 words
A control mechanism as claimed in claim 1, wherein said valve mechanism comprises a valve body, said first valve being an annular sleeve valve and cooperating with said second valve and said valve body.
Claim 13
Dependent Claim
23 words
A control mechanism as claimed in claim 1, wherein said second valve being a spool valve and cooperates with the said first valve.
Claim 14
Dependent Claim
18 words
A control mechanism as claimed in claim 1, wherein the said first and second valves are concentrically arranged.
Claim 15
Dependent Claim
72 words
A control mechanism as claimed in claim 1, characterized therein by an oil sump, a pump located in said oil sump, said valve mechanism comprising a valve body containing said first and second valves and said valve mechanism being positioned on the suction side of said pump and immersed and disposed in said oil sump and wherein said first and second valves slide relative to each other and to said valve body.
Claim 16
Dependent Claim
36 words
A control mechanism as claimed in claim 14, characterized therein by a profiled first cam, an operating lever mounting said first cam, a first hinged lever arranged to actuate said first valve from said first cam.
Claim 17
Dependent Claim
34 words
A control mechanism as claimed in claim 15, wherein a second hinged lever being disposed between said cam and said second valve, and said cam actuating said second valve through said second hinged lever.
Claim 18
Dependent Claim
43 words
A control mechanism as claimed in claim 16, wherein spring means being arranged for urging said first and second valves into contact with the respective said first and second levers, and means provided for oscillating said first valve in its entire sliding range.
Claim 19
Dependent Claim
22 words
A control mechanism as claimed in claim 1, wherein the said second valve is arranged to be actuated by said responsive means.
Claim 20
Dependent Claim
22 words
A control mechanism as claimed in claim 9, wherein a second cam supported on said operating lever for actuating said responsive means.
Claim 21
Dependent Claim
61 words
A control mechanism as claimed in claim 16, characterized therein by a third hinged lever hinged at a hinge point adjacent the hinge point of said first hinged lever, said first cam on the said operating lever also arranged to actuate said third hinged lever, and spring means arranged to urge said second hinged lever into contact with said first cam.
Claim 22
Dependent Claim
52 words
A control mechanism as claimed in claim 20, characterized therein by a pawl, a second spool valve carrying a ratchet, said ratchet coming into engagement with said pawl having a downwardly motion, whereby subsequent actuation of said pawl effecting movement of said spool valve to relieve the pressure in said hydraulic circuit.
Claim 23
Dependent Claim
72 words
A control mechanism as claimed in claim 21, characterized therein by a pin carrying said pawl on said first hinged lever operating the said first valve, an abutment on said third hinged lever, the opposite end of said pawl spaced from said pin resting against said abutment on said third lever, so that downward motion of said pawl occurs only when said third hinged lever moves relatively to said first hinged lever.
Claim 24
Dependent Claim
84 words
A control mechanism as claimed in claim 22, characterized therein by an abutment on said second hinged lever, the relative motion causing the downward actuation of the pawl occuring when said abutment on said second hinged lever operating said second valve comes up against and carries forward with its said first hinged lever actuating said first valve with said third hinged lever remaining stationary, any further forward motion of the said abutment causing forward movement of the said spool valve carrying the said ratchet.
Claim 25
Dependent Claim
93 words
A control mechanism as claimed in claim 1, characterized therein by a first lever and a second lever, a spool valve, a ratchet secured to said spool valve, a pawl mounted on said first lever and arranged to be contacted by said ratchet and having a slot therein, said second lever having a pin thereon arranged to engage in he slot in said pawl, wherein the pressure in said hydraulic circuit is relieved whenever the draft forces on said implement increases substantially and with the relief being effected through said second spool valve.
Claim 26
Dependent Claim
33 words
A control mechanism as claimed in claim 15, characterized therein by a single-acting external hydraulic cylinder, said first cam on said operating lever being profiled for control of said single-acting external hydraulic cylinders.
Claim 27
Dependent Claim
26 words
A control mechanism as claimed in claim 1, wherein an independently controlled infinitely variable orifice valve being provided in the discharge line of said hydraulic circuit.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-18 | 1975-04-19 | 1975-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-18 | 1979-04-19 | 1979-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-18 | 1983-04-19 | 1983-10-19 | $7700.00 | Window Closed / Lapsed |