US3686838A - Control arrangement for hydraulic systems - Google Patents

Control arrangement for hydraulic systems Download PDF

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Publication number
US3686838A
US3686838A US159623A US3686838DA US3686838A US 3686838 A US3686838 A US 3686838A US 159623 A US159623 A US 159623A US 3686838D A US3686838D A US 3686838DA US 3686838 A US3686838 A US 3686838A
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US
United States
Prior art keywords
connection
control
valve
hydraulic fluid
load
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US159623A
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English (en)
Inventor
Claude Comeau
Karl-Heinz Digel
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Robert Bosch GmbH
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Robert Bosch GmbH
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Publication date
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
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Publication of US3686838A publication Critical patent/US3686838A/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B20/00—Safety arrangements for fluid actuator systems; Applications of safety devices in fluid actuator systems; Emergency measures for fluid actuator systems
    • F15B20/002—Electrical failure
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/2496—Self-proportioning or correlating systems
    • Y10T137/2559—Self-controlled branched flow systems
    • Y10T137/265—Plural outflows
    • Y10T137/2657—Flow rate responsive
    • Y10T137/266—Primer valve

Definitions

  • ABSTRACT The return flow passage from the load is connected to a switchover valve, the position of which is controlled by a control flow that is present while the pump is operating. Should the pump be shut off when the control is unintentionally set to lower the load, lowering is prevented by a shut-off member in the switchover valve that is biased to close the return flow passage when the control flow is not present.
  • the invention relates to a control arrangement for a load that is fed from a source of hydraulic fluid, the control arrangement having a servo valve spool that in the neutral position closes the connection to the load, in a first work position connects the load to the source of hydraulic fluid, and in a second work position connects the load to the return flow connection.
  • the arrangement further comprises a control passage and a switchover valve for returning the hydraulic fluid from the source back to the source.
  • the German patent laid open to public inspection No. 1,507,164, FIG. 2 describes a control arrangement in which the hydraulic fluid directlyfrom the pump can be returned in the connection block when it does not pass through a valve to the load. In this case, if a valve is unintentionally operated, the load will sink even when the pump is shut off. It is frequently desired to prevent such lowering of the load when the pump is not operating.
  • the US. Pat. No. 3,299,903 describes a control arrangement having a plurality of servo valve spools which, to avoid cavitation, controls the return flow from the load in dependence on the feed pressure. Solely for this purpose, there is provided an additional valve that is operated by the hydraulic fluid. The arrangement has no switchover valve.
  • An object of the invention is to provide, in a control arrangement having a switchover valve, a certain and simple means for preventing lowering of the load when the servo valve spool is unintentionally operated.
  • the invention consists of a load connection, a return flow connection, valve means, such as a servo valve spool, having a neutral position for closing off the load connection, a first work position for connecting the load connection to the source of hydraulic fluid, and a second work position for connecting the load connection to the return flow connection, a switchover valve for returning the hydraulic fluid from the source back to the source, the switchover valve being connected in the return flow connection, control means for operating the switchover valve in dependence on a control flow of hydraulic fluid through the control means, the switchover valve including a shut-off member for closing the return flow connection in the event that the control flow of hydraulic fluid fails.
  • valve means such as a servo valve spool
  • FIG. 2 is a side view of the connection block of the control arrangement shown in FIG. 1;
  • FIG. 3 is a longitudinal section taken along line I-I of FIG. 2.
  • control arrangement 10 of the invention comprises a connection block 11, a blocking valve 12 for a single acting load 13, and an end plate 14.
  • connection block 11 has a housing 15, which incorporates a first bore 16 that has a conventional relief valve 17.
  • the pressure relief valve 17 protects a feed connection 18 from a return connection 19.
  • a shut-ofi member 24 is free to slide in a fluid-tight relationship in the second bore 21.
  • the member 24 is part of a switch-over valve 25.
  • a spring 26 pushes the shut-off member 24 into a first, rest, position that is defined by a spring washer 27. In this position, a first piston-like section 28 of the member 24 separates the feed connection 18 from the first chamber 22. In this position of the shut-off member 24, a second piston-like section 29 of this member separates the second chamber 23 from the first chamber 22.
  • the spring 26 is located in a chamber 31, from which latter a control passage 32 leads to a flange face 33.
  • a pressure regulating valve 34 which is incorporated in the shut-off member 24, connects the chamber 31 with the feed connection 18, which leads to the flange surface 33.
  • a pump 35 forces hydraulic fluid from a tank 36 into this feed connection 18.
  • a return flow connection 37 which is connected to the second chamber 23, also leads to the flange surface 33.
  • the blocking valve 12 which is shown in FIG. 1 in a somewhat simplified form, is a conventional valve for controlling the single acting load 13.
  • the servo valve spool 39 of the blocking valve 12 has three different positions: a neutral position 41, a raise position 42, and a lower position 43, whereby a load connection 44 can be hydraulically shut off or connected to a feed connection 45 or connected to a return connection 46.
  • a load connection 44 can be hydraulically shut off or connected to a feed connection 45 or connected to a return connection 46.
  • the servo valve spool 39 When the servo valve spool 39 is in the raise position 42, it also shuts off a control connection 47 for the switchover valve 25.
  • the servo valve spool When the servo valve spool is in either of the other two positions 41 and 43, it opens this control connection 47.
  • the feed connection 45, the return connection 46, and the control connection 47 in the blocking valve 12 begin at the flange face 49 of the blocking valve, this flange face being continuous with the end plate 14.
  • These connections, or passages, 45, 46, 47 are connected in the flange face 48 with the corresponding connections, or passages, 18, 37, and 32 in the connection block 11.
  • the feed connection 45 and the return connection 46 are closed by plugs 51 in the flange face 49.
  • the end plate 14 is a flange-connected to the flange face 49 of the blocking valve 12, the end plate 14 incorporating a discharge connection 52, which connects the control connection 47 of the blocking valve 12 to the tank 36.
  • the pressure regulating valve 34, the control connection, or passage, 32 and 47, and the discharge connection, or passage, 52 constitute the control connection, or passage, 53 of the switchover valve 25.
  • the arrangement just described operates in the following manner. If the servo valve spool 39 of the blocking valve 12 is in the illustrated neutral position 41, the load 13 is hydraulically locked, and the control connection 47 is turned on. If the pump 35 pushes hydraulic fluid through the feed connection 18, a control flow of hydraulic fluid moves through the control passage 53 into the tank 36. The pressure fall across the pressure regulating valve 34 keeps the switchover valve 25 open, and the largest part of the hydraulic fluid moved by the pump 35 flows through the return connection 19 to the tank 36.
  • the servo valve spool 39 If the servo valve spool 39 is moved to the lower position 43, the hydraulic fluid flowing back from the load 13 passes through the return flow connection 37 and the chamber 23 of the connection block 11.
  • the switchover valve 35 is opened, and the pump 35 can discharge into the tank 36, while a small control flow passes through the control passage 53 to the end plate 14, where it discharges into the tank 36.
  • the shut-off member 24 provides a connection from the chamber 23 to the return connection 19, so that the load can lower.
  • the control arrangement of the invention can be constructed as a plurality of control valves.
  • the control arrangement of the invention can be used with a harvester thresher, the load 13 operating the cutting table of the thresher.
  • a control arrangement for a hydraulic load that is supplied with hydraulic fluid from a source comprising, in combination, a load connection; a return flow connection; valve means having a neutral position for closing off said load connection, a first work position for connecting said load connection to the source of hydraulic fluid, and a second work position for connecting said load connection to said return flow connection; a switchover valve for returning the hydraulic fluid from the source back to the source, said switchover valve being connected in said return flow connection; control means for operating said switchover valve in dependence on a control flow of hydraulic fluid through said control means, said switchover valve including a shut-off member for closing said return flow connection in the event that said control flow of hydraulic fluid fails.
  • shut-off member moves between a first position in which said return flow connection is closed and a second position in which said return flow connection is open, and further including resilient means for biasing said shut-off member to said first position when said control flow of hydraulic fluid falls.
  • control arrangement as defined in claim 1, further including a plurality of control valves; a relief valve connected to the source for controlling the pressure of the hydraulic fluid therefrom; and connection block means for incorporating said relief valve and said switchover valve.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Multiple-Way Valves (AREA)
  • Lifting Devices For Agricultural Implements (AREA)
  • Safety Valves (AREA)
US159623A 1970-07-07 1971-07-06 Control arrangement for hydraulic systems Expired - Lifetime US3686838A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2033485A DE2033485C3 (de) 1970-07-07 1970-07-07 Steuereinrichtung für einen von einer Druckmittelquelle gespeisten hydraulischen Hubzylinder

Publications (1)

Publication Number Publication Date
US3686838A true US3686838A (en) 1972-08-29

Family

ID=5775953

Family Applications (1)

Application Number Title Priority Date Filing Date
US159623A Expired - Lifetime US3686838A (en) 1970-07-07 1971-07-06 Control arrangement for hydraulic systems

Country Status (6)

Country Link
US (1) US3686838A (enrdf_load_stackoverflow)
JP (1) JPS5019714B1 (enrdf_load_stackoverflow)
BE (1) BE769584A (enrdf_load_stackoverflow)
DE (1) DE2033485C3 (enrdf_load_stackoverflow)
FR (1) FR2098206B1 (enrdf_load_stackoverflow)
GB (1) GB1314793A (enrdf_load_stackoverflow)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3953959A (en) * 1973-06-14 1976-05-04 Decruyenaere Trudo Marie Josep Header height control mechanism
US4188772A (en) * 1977-06-06 1980-02-19 Harrington Manufacturing Company Hydraulic speed control system for the pick-up reel of a peanut combine
US20060254233A1 (en) * 2005-05-10 2006-11-16 Deere & Company, A Delaware Corporation Header hydraulic float suspension
US20070214760A1 (en) * 2005-05-10 2007-09-20 Bomleny Duane M Floating header with integrated float system for use with an agricultural windrower or combine

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4353289A (en) * 1980-05-29 1982-10-12 Sperry Corporation Power transmission
JPS63131652U (enrdf_load_stackoverflow) * 1987-02-20 1988-08-29
DE9310932U1 (de) * 1993-07-21 1993-09-30 Heilmeier & Weinlein Fabrik für Oel-Hydraulik GmbH & Co KG, 81673 München Elektrohydraulische Steuervorrichtung

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3138908A (en) * 1960-09-01 1964-06-30 Budzich Tadeusz Control in harvesting machinery
US3196599A (en) * 1963-05-20 1965-07-27 Elmo R Meiners Automatic height control system
US3299903A (en) * 1964-03-26 1967-01-24 Parker Hannifin Corp Fluid system and valve assembly therefor
US3623304A (en) * 1970-03-30 1971-11-30 Int Harvester Co Hydraulic system for supporting a harvester platform

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1020860A (fr) * 1949-06-02 1953-02-11 Hobson Ltd H M Système de commande pour appareils d'actionnement hydraulique

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3138908A (en) * 1960-09-01 1964-06-30 Budzich Tadeusz Control in harvesting machinery
US3196599A (en) * 1963-05-20 1965-07-27 Elmo R Meiners Automatic height control system
US3299903A (en) * 1964-03-26 1967-01-24 Parker Hannifin Corp Fluid system and valve assembly therefor
US3623304A (en) * 1970-03-30 1971-11-30 Int Harvester Co Hydraulic system for supporting a harvester platform

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3953959A (en) * 1973-06-14 1976-05-04 Decruyenaere Trudo Marie Josep Header height control mechanism
US4188772A (en) * 1977-06-06 1980-02-19 Harrington Manufacturing Company Hydraulic speed control system for the pick-up reel of a peanut combine
US20060254233A1 (en) * 2005-05-10 2006-11-16 Deere & Company, A Delaware Corporation Header hydraulic float suspension
US7207164B2 (en) * 2005-05-10 2007-04-24 Deere & Company Header hydraulic float suspension
US20070214760A1 (en) * 2005-05-10 2007-09-20 Bomleny Duane M Floating header with integrated float system for use with an agricultural windrower or combine
US7430846B2 (en) 2005-05-10 2008-10-07 Deere & Company Floating header with integrated float system for use with an agricultural windrower or combine

Also Published As

Publication number Publication date
JPS5019714B1 (enrdf_load_stackoverflow) 1975-07-09
DE2033485B2 (de) 1978-11-02
DE2033485C3 (de) 1979-06-21
FR2098206B1 (enrdf_load_stackoverflow) 1976-09-17
FR2098206A1 (enrdf_load_stackoverflow) 1972-03-10
BE769584A (fr) 1971-11-16
DE2033485A1 (de) 1972-01-13
GB1314793A (en) 1973-04-26

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