US2919680A - Piston-slide control valve for hydraulic presses - Google Patents

Piston-slide control valve for hydraulic presses Download PDF

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Publication number
US2919680A
US2919680A US47203154A US2919680A US 2919680 A US2919680 A US 2919680A US 47203154 A US47203154 A US 47203154A US 2919680 A US2919680 A US 2919680A
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United States
Prior art keywords
control
piston
working
valve
channels
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Expired - Lifetime
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English (en)
Inventor
Hans Scharringhausen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Scharringhausen Maschb Ges M B
Scharringhausen Maschinenbau GmbH
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Scharringhausen Maschb Ges M B
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
    • B30B15/16—Control arrangements for fluid-driven presses
    • B30B15/24—Control arrangements for fluid-driven presses controlling the movement of a plurality of actuating members to maintain parallel movement of the platen or press beam
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
    • B30B15/16—Control arrangements for fluid-driven presses
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K11/00—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves
    • F16K11/02—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit
    • F16K11/06—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements
    • F16K11/065—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements with linearly sliding closure members
    • F16K11/07—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements with linearly sliding closure members with cylindrical slides
    • 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
    • Y10T137/8593—Systems
    • Y10T137/86493—Multi-way valve unit
    • Y10T137/86574—Supply and exhaust
    • Y10T137/86582—Pilot-actuated
    • Y10T137/86606—Common to plural valve motor chambers

Definitions

  • control valves of the piston slide type with hydraulic presses such as plate working machines having several pressing cylinders.
  • These control valves are usually arranged between the supply source for the pressure medium, such as, for instance, a
  • Control valves of this kind may control the flow of the pressure medium to and from either one single or several working cylinders, depending on the manner of their being arranged in the flow system.
  • one single piston edge, or both piston edges, i.e., the upper and the lower edge, and in the second case, usually both piston edges, are utilized as steering edges in the valve cylinder.
  • the control pistons are moved by any kind of steering mechanism suitable for this purpose and free or close the passage for influx or outflow of the pressure medium to a greater or smaller degree, thereby controlling the movement of the pistons in the working cylinders.
  • the working pistons may either be single acting, in which case the return movement of the pressure tools is effected by strong springs, or by special so-called return pistons, or they may be double acting and may effect the return movement themselves.
  • My invention is based on observations made with double acting working pistons.
  • the upper piston face of such double acting pistons comprising the surface F upon which the pressure medium is acting during the working stroke is known to be substantially larger than the bottom face of the piston having the area F which is acted upon during the back stroke, because the face surface of the latter is diminished by the cross section of the piston rod connected with the piston.
  • the piston velocity during the back stroke, V must be greater than the piston velocity during the working stroke, V according to the atent ice reciprocal ratio of the piston surfaces, if the same pressure of, for instance, atmospheres excess pressure, or more, is acting upon the piston during both movements.
  • My invention solves this problem by providing the piston slide of the control valves in the aforesaid and similar cases, with a plurality of control edges and with a corresponding plurality of channels and grooves for the influx and outflow of the pres e medium, which channels and grooves are connected with each other by means of annular feeding and outflow channels, thus replacing the hitherto used single influx and outflow channels for the passage of the pressure means, and the single control edge opening or closing them.
  • 1 maintainvunchanged on the one hand the high sensitiveness oflregulation, and on the velocity as Well as the diameter of the control piston, while I nevertheless achieve a considerably reater cross section for the passage ot" the pressure medium.
  • My invention thus achieves an increased regulating velocity at the working stroke as well as the theoretical value of piston velocity at the back stroke.
  • Figure 1 represents a schematic view of the arrangement of a piston slide valve control according to my invention, in partial section;
  • Figure 2 shows the left hand control piston valve of Figure l in enlarged scale.
  • control means comprises as main element (which is usually employed in pairs) two working or pressing cylinders .a and 115, each having a double acting working piston 2a and 21) respectively, and piston rods and 3b, as well as two control cylinders 4a and 25, each having a control piston 5a and 5b, together with control piston rods 6a and 622 respectively.
  • the piston rods 3:: and 3b engage the pressing or pressure platen of the folding press which is not shown.
  • control rods 6a and 6b possess at their lower or outer ends racks 7a and 7b respectively which engage control pinions 9a and 9b which are in turn mounted on a common control shaft
  • Th control shaft 8 is preferably mounted on the dis laceable press platen, for instance by means of bearings indicated at Mia and 18b.
  • the pressure medium for it stance a pressure oil of 100 atmospheres excess pressure, is supplied from a pressure medium source (not shown) by way of a shiftable main valve 11 and through the conduit 32 to both control cylinders 4a and db, and is returned from the cylinders through the return conduit if).
  • the main valve ll is also represented by way of example as a piston valve. Supplying of the pressure medium, for instance from a pressure tank, takes place way of the check valve 11a provided inthe conduit 12. When the piston 22 of valve 1 moves upwardly the supply of pressure medium is throttled. If the piston 22 moves downwardly, the conduit of the valve is equally interrupted. in its intermediate position, however, the pressure medium supplied from the tank is returned through the valve and in this position of the main valve 11 the working pistons 2a and 2b remain stationary in their momentary position.
  • Conduit 12 ends in their branch conduits 121, 122 and 123 for each control cylinder, and conduit 13 ends in three branch conduits 131, 132 and 133 for each control cylinder.
  • each control cylinder (4a or 41) is provided with a number of annular recesses 2la2lp which are distributed at determined distances over the length of bore 2%.
  • conduit 14a is connected to a channel Mil in the control valve cylinder do from which branch channels Mil, 142, 143, 144 and 145 establish communication with annular recesses 21c, 21 211', 21k, and 2111 respectively.
  • conduit 3a is connected to a channel in cylin-- der which communicates by way of branch channels i, 152., 153', and 155 with annular recesses 21a, 21d, Zlm and 21p respectively.
  • Each long control piston e.g. piston 5a in Figure 2
  • Each long control piston comprises a number of lands Sll, 52, 53, 54-, 55 and 5-6 and is provided with grooves 31, 32, 33, 34 and 35 be-- tween each pair of adiacent lands, thus defining a. plural ity of control edges where each land and groove meet,. which control edges cooperate with corresponding recesses 21a 21p.
  • Branch conduit 133 of return conduit 13 is connected to the top of cylinder bore 28.
  • the lowermost land 51 in cooperation with the wall portion of bore Zll which it contacts, serves to diminish the pressure on the packing 23 about the control rod 6a, and on the guide bush 17a for the latter.
  • control piston 53:: or 5b
  • the great length and the multiple subdivision of the control piston also otters the added advantage-- over a conventional increase in diameter of the piston, that it results in a greatly improved guidance of the pistons in the long cylinder bore 20.
  • each control piston is thus provided with five lands and intermediate annular grooves, and consequently possesses ten control edges 41, 42a, -Zb, 43a, 43b, 44a, 44b, 45a, 45b, and 46; and the cylinder wall of each control valve is provided, again by way of a preferred example only, with fifteen annular grooves and corresponding channels in the cylinder block.
  • Five control on the control pistons namely 42a, 43a, l la, 44b and 45b are provided for cooperation with the top surface of the working piston 2a (or 2b) through.
  • five control edges for each end surface of the working pistons three are for instance, used for controlling the influx of the pressure medium. to, and two for controlling the outflow of the pressure medium from the working pistons. Thereby the hydraulic cross sectional resistance to the pressure medium flow through each control valve is reduced to one-third for the influx and to one-half tor the outflow of the pressure. medium.
  • the cylinder heads are connected by the aforesaid conduits 133 with the return conduit 13. The.
  • branch channels 151, 152 and 153 which lead to the two conduits 15a and 15b serve for feeding the pressure medium to working cylinder 1a (and 1b) during the back stroke and the two upper branch channels 154 and 155 serve for withdrawing the pressure medium during the working stroke.
  • control edges and annular grooves are so coordinated with each other that (in the case of the embodiment as shown in the drawings) the three parallel feeding recesses 21c, 21] and 211' connected to conduits 14a and 14b) are opened during the working stroke, i.e., when the pistons 2a and 2b move downwardly, while the two parallel outflow recesses 21k and Ziln connected to conduits 14a (and 1412), as well as the three parallel feeding recesses 21a, 21d and 21g connected to conduits 15a (and 15b) are closed, while simultaneously the two parallel outflow recesses 21m and 21p connected to the conduits 15a (and 15b) are open.
  • the opening and closing of the annular grooves takes place in inverted order.
  • all parallel connections i.e., the connecting channels of the annular grooves are located in the cylinder body of the control valves.
  • the internal channels in the control valves are preferably arranged in different planes. In the drawings the channels are all shown as being arranged in the plane of the drawings for drawing purposes only. However, the interruption of the channels leading from the conduits 12 and 13 to the annular grooves is intended to show that the channels are to be arranged in different planes. The last-named channels should be arranged, for instance, in a plane perpendicular to the plane of the drawings.
  • the channels through which the pressure medium passes in the same direction i.e., on the one side the channel connected to conduits 12 and 13 should in practice be at a level providing the necessary sealing effects of the lands of the pistons above the level of the channels connecting the conduits 14a, 14b, 15a and 15b respectively.
  • the shortest possible length of the passages through the valves, and correspondingly the lowest possible flow resistances are obtained.
  • the method of a diflerentiated feeding of the pressure medium to two or more working cylinders of hydraulic presses and similar machines which can be carried out with the aid of control valves according to my invention in a particularly advantageous manner, is known as such and need not be described in greater detail. It allows to feed the pressure medium to each Working cylinder under such pressure and in such quantity that the resulting factor of pressures exercised by the hydraulic cylinders coincides with the resulting factor of the counterforce exercised by the pressed working piece.
  • This 6 allows in particular to achieve a parallel and straight guidance of the press platen or other similar tools of hydraulic machines free of binding.
  • the control arrangement according to the embodiment as shown in the drawings provides for the following operation: the piston rods 6a and 6b, and together therewith the control pistons 5a and 5b are at first adjusted according to the desired control operation.
  • the pinions a and 9b connected with the control shaft 8 are idle at this stage.
  • the operation of the entire control arrangement takes place without any complicated insertion of levers, rod mechanisms, or other organs, thus being automatic and at the same time particularly sensitive.
  • the means indicated at 18a and 18b serve for the longitudinal adjustment of the control piston rods 6a and 6b in order to achieve an exact ad justment of the central or starting position of the control pistons 5a and 5b relative to each other and to their driving means.
  • Each control piston of the main valve 11 thus reciprocates between two extreme positions. In each of the latter positions, one annular recess is closed entirely by a piston land. In the lowermost position of the piston the upper annular recess (21p) is closed, and in the uppermost piston position the lowest annular recess (21a) is closed.
  • the check valve 11a thus serves to withdraw the pressure medium from the control valves when the control pistons are in central position, and to feed pressure medium to the control valves when the control pistons are in an end position either during upward or downward movement of the working pistons.
  • a special advantage of my invention resides in the fact that through providing a plurality of control edges on the control valve pistons, heating of the pressure medium is avoided. Such heating occurs frequently through friction of the pressure oil, if only one control edge is available, as is the case in the hitherto known valves. Heat of the pressure oil above F. may cause the oil to be decomposed or saponified and thus to become unsuitable for further use. This will not occur in control valves according to my invention.
  • control valves according to my invention may be constructed in a variety of manners and may also be arranged differently from the embodiment shown in the drawings, which has been used as an explanatory example only.
  • a control valve according to my invention may also be used for controlling machines having only single acting working pistons.
  • a piston-slide control valve for use with hydraulic presses and the like, having several pressing cylinders with double-acting working pistons, said valve comprising a cylinder body having a bore therein, a plurality of annular recesses in said bore, a control piston reciprocatingly mounted inside said bore and comprising a plurality of alternate lands and annular grooves forming a first number of control edges on said control piston for opening simultaneously during a given movement of said control piston certain of said recesses and a second number of control edges for closing the remaining recesses and invertedly closing the former and opening the latter recesses during a movement of the control piston in opposite direction, and a number of channels corresponding to the number of said recesses and connecting the latter with conduits for feeding and withdrawing the pressure medium for said pressing cylinders; each of said opening control edges being disposed with regard to the next adjacent one at a distance equal to the distance between those annular recesses cooperating with said opening control edges, thereby causing all of said opening control edges to cooperate simultaneously with
  • a control valve according to claim 1 wherein several of said annular recesses inside said cylinder bore are connected in parallel at a determined distance from one another for feeding the pressure medium, and that separately therefrom the remaining annular recesses are connected in parallel and at said determined distance from one another for withdrawing the pressure medium.
  • a control valve according to claim 1 wherein all of said annular recesses and channels conducting the flow of pressure medium to and from the head surface of said double-acting working cylinders are separate from all of said annular recesses and channels serving the tail end of said double-acting Working pistons.
  • a control valve according to claim 1 wherein said annular recesses and channels are divided into a first and a second group, a first joint conduit being provided for connecting said first group of annular recesses and channels with the head surface of said double-acting working pistons, and a second joint conduit being provided for connecting said second group of annular recesses and channels with the tail surface of said working pistons.
  • a control valve according to claim 4- wherein all said channels are arranged inside said cylinder body of said valve, said channels being provided in different planes through the axis of said cylinder, each pair of a feeding and a corresponding withdrawing channel being arranged on opposite sides of said bore with regard to one another, in planes spaced only by the distance required for sealing by said control piston lands.
  • a control valve wherein the total number of said control edges is ten and wherein five of said control edges are provided by certain lands on said control piston for controlling the flow of pressure medium to and from the head surfaces of said working pistons, and five other control edges are provided by certain lands on said control piston for controlling the flow of pressure medium to and from the tail surfaces of said working pistons, three of the former and three of the latter control edges controlling the flow of pressure medium to said working pistons, and two of the former as well as two of the latter control edges controlling the flow of pressure medium from the same.
  • a piston slide control valve for use with a hydraulic press having at least one pressing cylinder with a doubleacting piston therein, a source of hydraulic pressure fluid, and connecting lines from said control valve to said pressing cylinder and from said valve to said source of hydraulic pressure fluid for the passage of said fluid therethrough, in either direction, said valve comprising a casing having a central bore being closed at both ends, and a plurality of annular recesses in the wall of said bore, a control piston disposed for reciprocating movement in said bore, said piston comprising several lands and annular grooves therebetween, each land and adjacent groove forming a circumferential control edge of said piston, and a plurality of channels in said casing connecting said connecting lines with said annular recesses so as to establish communication with determined groups of the latter for the flow of pressure fluid in parallel through the same in a given direction of flow, said annular recesses in the wall of said bore, and said annular grooves of said piston being so distributed over the length of the bore and piston respectively, that by the movement of said piston in a
  • a piston slide control valve for use with hydraulic presses and the like which presses have several pressing cylinders with double-acting working pistons and a source of hydraulic fluid therefor, said control valve comprising a cylinder body having a bore therein, a control piston reciprocatingly mounted inside said bore, a
  • first conduit means for feeding hydraulic fluid from said fluid source to said valve and comprising a first number of parallel channels opening each into one of said first annular recesses
  • second conduit means for withdrawing hydraulic fluid from said valve and comprising a second number of parallel channels each opening into one of said second annular recesses
  • third conduit means for the flow of fluid alternatingly in different direction between said control valve and one of said pressing cylinders, and comprising a plurality of channels each connected to one of said third annular recesses
  • said control piston comprising a plurality of lands bearing two groups of control edges, one of which groups opens communication between certain of said third annular recesses simultaneously with all of said first and second annular recesses so as to cause fluid flow between said valve and said pressing cylinder in one direction during a given direction of movement of said piston in said valve bore, and the other group opens communication between the other recesses of said third annular recesses simultaneously with all of said first and second annular recesses so as

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Control Of Presses (AREA)
  • Fluid-Driven Valves (AREA)
US47203154 1953-11-30 1954-11-30 Piston-slide control valve for hydraulic presses Expired - Lifetime US2919680A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEM21019A DE1007627B (de) 1953-11-30 1953-11-30 Steuerventil mit Kolbenschieber fuer hydraulische Pressen

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DE (1) DE1007627B (nl)
NL (1) NL88915C (nl)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3223379A (en) * 1962-10-16 1965-12-14 Elmer L Erickson Apparatus for producing prestressed concrete articles
US3304840A (en) * 1965-10-11 1967-02-21 Elmer L Erickson Means for selectively operating plural working members
US3313181A (en) * 1961-10-30 1967-04-11 Clark Equipment Co Transmission control
US3322038A (en) * 1964-04-09 1967-05-30 Sperry Rand Corp Hydraulic hammer
US3378898A (en) * 1965-03-05 1968-04-23 Du Pont Textile package laydown device
US3395763A (en) * 1965-09-22 1968-08-06 Curtiss Wright Corp Hydraulic control system for variable pitch propeller
US3913450A (en) * 1973-05-11 1975-10-21 Dreis & Krump Manufacturing Co Hydraulic Control system for press brakes or the like
US11130521B2 (en) * 2018-07-23 2021-09-28 Jtekt Corporation Steering control unit
RU2772517C2 (ru) * 2020-11-03 2022-05-23 Федеральное государственное бюджетное образовательное учреждение высшего образования "Красноярский государственный аграрный университет" Устройство для синхронизации движения поршневых штоков двухцилиндрового маслопресса

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2541934B1 (fr) * 1983-03-04 1986-10-17 Poncet Pierre Dispositif de reglage du parallelisme et de la planeite des plateaux dans les presses a mouler

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1016167A (en) * 1909-11-19 1912-01-30 John Austen Mcculloch Valve.
US2522481A (en) * 1948-08-14 1950-09-12 Norton Co Fluid motor
US2612184A (en) * 1949-01-14 1952-09-30 Cincinnati Milling Machine Co Sensitive hydraulic tracer valve
US2718877A (en) * 1954-05-07 1955-09-27 Northrop Aircraft Inc Hydraulic servo with integral equalization

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE484313C (de) * 1927-05-19 1929-10-15 Maschf Regelvorrichtung fuer hydraulische Pressen mit mehreren Presszylindern
US2592338A (en) * 1946-04-17 1952-04-08 Plant Choate Mfg Co Inc Hydraulic system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1016167A (en) * 1909-11-19 1912-01-30 John Austen Mcculloch Valve.
US2522481A (en) * 1948-08-14 1950-09-12 Norton Co Fluid motor
US2612184A (en) * 1949-01-14 1952-09-30 Cincinnati Milling Machine Co Sensitive hydraulic tracer valve
US2718877A (en) * 1954-05-07 1955-09-27 Northrop Aircraft Inc Hydraulic servo with integral equalization

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3313181A (en) * 1961-10-30 1967-04-11 Clark Equipment Co Transmission control
US3223379A (en) * 1962-10-16 1965-12-14 Elmer L Erickson Apparatus for producing prestressed concrete articles
US3322038A (en) * 1964-04-09 1967-05-30 Sperry Rand Corp Hydraulic hammer
US3378898A (en) * 1965-03-05 1968-04-23 Du Pont Textile package laydown device
US3395763A (en) * 1965-09-22 1968-08-06 Curtiss Wright Corp Hydraulic control system for variable pitch propeller
US3304840A (en) * 1965-10-11 1967-02-21 Elmer L Erickson Means for selectively operating plural working members
US3913450A (en) * 1973-05-11 1975-10-21 Dreis & Krump Manufacturing Co Hydraulic Control system for press brakes or the like
US11130521B2 (en) * 2018-07-23 2021-09-28 Jtekt Corporation Steering control unit
RU2772517C2 (ru) * 2020-11-03 2022-05-23 Федеральное государственное бюджетное образовательное учреждение высшего образования "Красноярский государственный аграрный университет" Устройство для синхронизации движения поршневых штоков двухцилиндрового маслопресса

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Publication number Publication date
NL88915C (nl) 1958-08-15
DE1007627B (de) 1957-05-02

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