US3819307A - Stability means for a controller for fluid pressure operated devices - Google Patents

Stability means for a controller for fluid pressure operated devices Download PDF

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Publication number
US3819307A
US3819307A US30003772A US3819307A US 3819307 A US3819307 A US 3819307A US 30003772 A US30003772 A US 30003772A US 3819307 A US3819307 A US 3819307A
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United States
Prior art keywords
apertures
controller
spool
fluid
slots
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English (en)
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S Uppal
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Eaton Corp
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Eaton Corp
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Priority to US30003772 priority Critical patent/US3819307A/en
Priority to CA183,886A priority patent/CA962550A/en
Priority to IT3047573A priority patent/IT998896B/it
Priority to AU61714/73A priority patent/AU471180B2/en
Priority to DE19732353068 priority patent/DE2353068A1/de
Priority to FR7337963A priority patent/FR2203953A1/fr
Priority to JP11978473A priority patent/JPS4994028A/ja
Priority to BR832073A priority patent/BR7308320D0/pt
Priority to GB4960273A priority patent/GB1444019A/en
Priority to GB4804875A priority patent/GB1444020A/en
Application granted granted Critical
Publication of US3819307A publication Critical patent/US3819307A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
    • B62D5/09—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle characterised by means for actuating valves
    • B62D5/093—Telemotor driven by steering wheel movement
    • B62D5/097—Telemotor driven by steering wheel movement gerotor type
    • 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
    • Y10T137/86638—Rotary valve
    • Y10T137/86646—Plug type
    • Y10T137/86662—Axial and radial flow

Definitions

  • ABSTRACT An improved, stabilizing means for a controller operatively connected to a servomotor for controlling flow to a fluid pressure device.
  • a neutral position a plurality of flow control ports in first and second valve members, one member disposed within the other, are in registry with one another to direct inlet pump flow to an outlet.
  • the flow control ports are positioned a predetermined degree out of registry as one valve member is rotated relative to the other to thus communicate inlet fluid to the servomotor and metered fluid from the servomotor to the fluid pressure device.
  • the improved stability means dampens the sudden pressure changes within the modulating range as the controller is moved from one position to another. More particularly the stabilizing means comprises an orifice arrangement for augmenting ilow which is disposed relative to certain flow control ports in one valve member to control the flow area into flow ports of the second member upon relative movement of the valve members.
  • This invention relates to a controller for fluid pressure operated devices and more particularly to an arrangement for stabilizing the fluid flow therethrough.
  • the invention is particularly applicable to a controller-gerotor application for use with a power-steeringthe invention has applicability to any type of modulating valve arrangement for actuating a fluidic device by supplying pressure thereto.
  • a power-steering control of the type to which this invention pertains is described in U.S. Reissue Pat. No. 25,126 to L. L. Charlson, reissued Feb. 20, 1962 and assigned to the present assignee.
  • the Charlson patent discloses a modulating valve unit or controller feeding pressure into and out of a servomotor of the gerotor type.
  • the controller disclosed comprises a controller body to which is secured a pump inlet, a reservoir outlet and two conduits, inlet and outlet, feeding to a power-steering cylinder.
  • the vehicle steering wheel is directly connected to the controller and when the steering wheel is in a neutral position, defined as any nonrotating or stationary position, fluid is supplied from the pump inlet, through the-controller to the reservoir out let.
  • Charlson achieves this control of fluid direction by employing a modulating valve body in working communication with a gerotor servomotor comprising a fixed ring member receiving a rotating and orbiting star-member.
  • the valve body comprises a housing containing the inlet, outlet and cylinder lines along with valving passages communicating with the gerotor.
  • a rotatable, hollow cylindrical sleeve member Disposed within the housing is a rotatable, hollow cylindrical sleeve member, having various passages, recesses, chambers, etc. adapted to be in communication with the various lines in the instances described above.
  • a rotatable, hollow, cylindrical spool member also having various chambers, passages, etc. whereby fluid is communicated through the aforementioned passages in the sleeve member.
  • the spool is fixed to the steering wheel and also coupled to the sleeve by a pin and set of springs in a manner which permits a predetermined degree of relative movement between the sleeve and spool before the spool and sleeve are commonly rotated thereby.
  • a dogshaft Also extending within the spool is a dogshaft, splined at one end to the star member and bifurcated atthe other end to receive the pin; the dogshaft thus rotates the pin in direct proportion to the star members rotation.
  • Charlsons device did not provide enough modulating range between sleeve and spool or neutral band width necessary to give the driver the best possible control of the steering arrangement. This resulted from the particular aperture arrangement in the spool and sleeve which caused these apertures to move out of registry with one another upon relatively slight movement of the wheel from neutral. When this occurs, the rapid pressure change within the controller may cause oscillation between spool and sleeve, in turn causing vibration to be felt in the steering wheel. Also, in Charlsons device the spool is not pressure balanced which may cause binding of the sleeve on the spool under higher pressures, unless the diametral clearance between spool and sleeve is increased causing unwanted leakage and slip.
  • a fluidic device coupled to a modulating valve arrangement comprising a controller and servomotor which functions in a manner similar to that of the aforedescribed Charlson device.
  • the controller comprises a stationary outer casing having at least a pump inlet and an outlet, either closed or open to a reservoir, and also interchangeable inlet and outlet lines to a cylinder.
  • Received in the casing is a hollow, clindrical, rotatable sleeve member.
  • a hollow cylindrical spool member having one end fixed to the steering wheel is disposed within the sleeve member.-
  • a pin and slot arrangement between the spool and sleeve limits maximum movement of the spool and sleeve relative to one another.
  • a set of leaf springs between sleeve and spool provides means for returning the spool and sleeve back to a neutral position when steering wheel is released.
  • Means are provided for driving the sleeve in direct relation to the output of the servomotor.
  • the sleeve member has at least one row of circumferentially spaced first apertures. Circumferentially aligned with and longitudinally spaced on one side of the first apertures is at least one row of smaller-sized second apertures.
  • a plurality of flow augmentation orifices of predetermined geometric configuration are longitudinally positioned and circumferentially spaced with respect to the second apertures so that an orifice is positioned in predetermined circumferential distance on each side of each of said second apertures.
  • the spool member has a number of axially extending configured slots therethrough; the number and position corresponding to and circumferentially aligned with the first and second apertures.
  • a still further object of the invention is to provide a relationship between the resistance to flow from feed to cylinder and return from the cylinder to reduce the possibility of cavitation in the system.
  • Yet another object is to provide in a controller for a fluid pressure device having a spool valve member and a sleeve valve member, pressurizing means to maintain the spool and sleeve members in neutral or centrally disposed relation and to minimize distortion of the sleeve to prevent binding between said spool and sleeve.
  • FIG. 1 is a diagram showing the controller used in the power steering system of a vehicle
  • FIG. 2 is an enlarged view partly in elevation and partly in axial section taken substantially along line 22 of FIG. 1, some parts being broken away;
  • FIG. 3 is an axial, sectional view taken substantially on the Line 33 of FIG. 2;
  • FIG. 4 is a transverse sectional view taken substantially along line 44 of FIG. 3, some parts being broken away;
  • FIG. 5 is a fragmentary view in side elevation of one of the valve elements in the controller
  • FIG. 6 is a fragmentary view in side elevation of another valve element in the controller
  • FIGS. 7-12 are views in transverse sections taken respectively along lines 7-7, 8-8, 99, 10-10, lIl1,12-12 of FIG. 3;
  • FIG. 13 is a graph of valve deflection versus pressure change
  • FIGS. l4, l5, and 16 are overlaying views of apertures and orifices in valve elements at various valve deflections.
  • Controller A operatively connected to a servomotor B for controlling a power-steering arrangement C.
  • Controller A comprises a primary valve, hereafter referred to as spool member 10 disposed within a follow-up valve hereafter referred to as a sheeve member 12 which in turn is disposed within a tubular casing 14.
  • Stabilizing means D is provided for controller A which comprises a plurality of orifices 16 in geometric arrangement with a plurality of apertures 20 in sleeve member 12 coordinating with a plurality of slots 18 in spool member 10.
  • tubular casing 14 of controller A is shown as having a pump inlet 22 which is connected by means of a conduit 23 to a source of fluid pressure such as a pump 24 which in turn is connected to a reservoir of tank 25 by a conduit 26.
  • Tubular casing 14 is also provided with a reservoir outlet 28 for return of fluid to reservoir 25 by means of conduit 29.
  • Tubular casing 14 is also provided with a pair of interchangeable cylinder inlets and outlets 31, 32 with respective conduits 33, 34 leading to opposite ends of a power-steering cylinder 35 having mounted for axial reciprocatory movement therein a piston equipped plunger rod 36.
  • the plunger rod 36 is connected to the steering linkage 38 of a vehicle, not shown, by means of the usual bell crank 39 and rigid link 40 whereby the vehicle wheels 41 are steered in the usual manner.
  • the gerotor illustrated comprises the usual internally toothed ring member 44 which is fixed receiving an externally toothed star member 45 which is free to rotate and orbit about its axis. Ring and star members 44, 45 are so arranged that their teeth 46, 47 respectively move into and out of interrneshing engagement and define expanding and contracting fluid chambers 48 during rotary and orbital movement of ring member 44.
  • the construction and operation of ring and star members 44, 45 is similar to that shown and described in US Letters Pat. No. 2,821,171.
  • the externally toothed star member 45 partakes of an orbital movement about the axis of the internally toothed ring member 44 rotating one tooth spacing for every orbit thereof.
  • the star member 45 will rotate once on its own axis during six cycles of orbital movement thereof about the axis of the internally tooth ring member 44.
  • the servomotor arrangement B also comprises an end plate 52 abutting an axial end face 53 of star and ring members 45, 44 along with a bearing plate 54 abutting the opposite axial end face 55 of ring and star members 44, 45; bearing plate 54 being intermediate the controller assembly and servomotor arrangement A, B.
  • Bearing plate 54 has a centrally disposed opening 56 for receiving the shaft portion 57 of a dogshaft or drive shaft 58 having a crowned splined head 59 in driving engagement with a splined'central opening 60 in star member 45.
  • Bearing plate 54 is also shown as having seven valving ports 63 adapted to be in communication with pressure chambers 48 in a manner known to those skilled in the art.
  • the servomotor arrangement B thus described is secured to the tubular casing 14 of controller A by bolts 64 extending through the end plate 52, ring member 44 and bearing plate 54 to engage suitably threaded openings in tubular casing 14.
  • Servomotor arrangement B is provided with suitable seals 66 to prevent leakage therefrom.
  • the controller assembly comprises a tubular casing 14 having a substantially cylindrical opening 70 extending therethrough into which is disposed a hollow cylindrical sleeve member 12 which in turn receives a hollow cylindrical spool member 10.
  • Tubular casing 14 has a pumy inlet port 72, a reservoir outlet port 73, interchangeable inlet and outlet ports 74, communicating respectively with a pump inlet groove 76, an outlet reservoir groove 77, interchangeable inlet and outlet cylinder grooves 78, 79;
  • each groove opening to the cylindrical opening 70 is also seven L-shaped valving passages 81 are circumferentially spaced in tubular casing each valving passage 81 having one end 82 adapted to communicate with a valving port 63 in the bearing plate 54 and its other end 83 opening to the cylindrical opening 70 in tubular casing 14.
  • a plurality of circumferentially spaced threaded holes 85 are shown drilled in one axial end face 86 of tubular casing 14 to secure controller A to a mounting bracket 87 as shown in FIG. 1 by means of machine screws and the like.
  • Sleeve member 12 Rotatably disposed within the cylindrical opening 70 in tubular casing 14 and in close engagement with the walls of the opening is sleeve member 12.
  • Sleeve member 12 has one axial end 89 abutting bearing plate 54 with its other axial end 90 abutting an end cap88.
  • End cap 88 is shouldered and received in a similarly stepped recess 91 in tubular casing 14 and secured in this position by a snap ring 92 or the like.
  • Nestingly received within the sleeve 12 and concentric therewith its spool member 10 which is hollowed for the greater part of its length to thereby define an axial recess or passage 94.
  • One axial end 96 of spool 10 is in substantially abutting engagement with bearing plate 54 with its opposite end 97 abuttingly engaging thrust bearing 98 mounted within the shouldered portion of end cap 88.
  • Seals 99, 100 between tubular casing 14 and end cap 88 and end cap 88 and spool 10 respectively seal the controller arrangement A.
  • transverse drive pin 102 extends radially through a pair of diametrically opposed circumferentially extended slots 103 in spool 10 and the opposite ends of drive pin posed openings 104 in sleeve member 12.
  • slots 18 are longitudinally located at the bearing plate axial end portion 96 of spool 10 and adapted to be in communication with pump inlet groove 76. Slots 18 form part of stabilizer means D and will be referred to in detail hereafter. It should suffice to state at this time that slots 18 are adapted to be in communication with pump inlet 22 when the spool and sleeve 10, 12 are in neutral position and some degree out of communication with pump inlet 22 when the controller A is actuated by rotatably displacing spool 10 relative to sleeve 12.
  • each feed slot 114 extends longitudinally from the valving passage openings 83 past one cylinder groove 78 and temiinates at a point just beyond the other cylinder groove 79 in tubular casing 14.
  • Circumferentially spaced between feed slots 114 and spaced in line with and longitudinally extending a distance equal that of one cylinder groove 78 are six first return slots 116 communicating with axial passage 94 in spool 10 which are shallow to give resistance to the return flow from the cylinder to reduce cavitation. Also circumferentially spaced between feed slots 114 and spaced in line with and longitudinally extending a distance from the second cylinder groove 79 to the outlet reservoir groove 77 in tubular casing 14 are four second return slots 118 opening to passage94 in spool 10 which are deep to have the same area as the six 116 shallow slots.
  • outlet holes 120 are interposed between second return slots 118 and aligned with the outlet reservoir groove 77.
  • Outlet holes 120 extend through spool 10 and are adapted to be in communication with passage 94.
  • the two slots 160, 162 communicating with the pin slot of spool 10 are for uniform circumferential pressure balance of the spool.
  • the return slots were discontinued in two steps 116 and 118 to connect the feed slots 114 for pressure balancing and for collector function.
  • a first pressure balancing groove 122 peripherally extending around the exterior surface of spool 10 is longitudinally aligned between the inlet and outlet cylinder grooves 78, 79.
  • a second pressure balancing groove 124 extending peripherally around the exterior surface of spool member 10 is longitudinally aligned between one cylinder groove 78 and valving passage opening 83 for purposes which will hereafter be explained.
  • a plurality of apertures 20 and orifices 16 are longitudinally located at the bearing plate axial end portion 89 of the sleeve and are adapted to be in communication with pump inlet groove 76.
  • Apertures 20 and orifices 16 form part of stabilizing means D and will be referred to in detail hereafter, it being sufficient to state that the apertures 20 and slots 18 in spool 10 align with one another to provide a fluid flow path when controller A is in a neutral position and are displaced relative to one another to close off the fluid flow path as controller A is actuated.
  • valving apertures 1 13 in sleeve 12 communicate pump inlet pressure from valving shots 112 via valving passages 81 to half the pressure chambers 48 in servomotor B which are at high pressure while the other pressure chambers 48 at low pressure are communicated to feed slots 114 in spool 10 via other valving apertures 113 in sleeve 12 in a sequential manner known to those skilled in the art.
  • first return apertures 117 Longitudinally spaced from valving apertures 113 and aligned with one of the cylinder grooves 78 in tubular casing 14 are six circumferentially spaced first return apertures 117.
  • First return apertures 117 are axially aligned with first return slots 116 in spool 10.
  • second return apertures 119 Longitudinally spaced from first return apertures 117 and in alignment with the other cylinder line groove 78 in tubular casing 14 are six circumferentially spaced second return apertures 119.
  • Second return apertures 119 are axially aligned with second return slots 118 in spool 10. As best shown in FIGS.
  • apertures 117 and 119 are circumferentially spaced relative one another in such a manner that when return apertures 117 are in communication with return slots 116, the second return apertures 119 are out of communication with second return slots 118 and vice-versa.
  • Longitudinally spaced from additional return apertures 119 and aligned with outlet reservoir groove 77 are ten outlet apertures 121 circumferentially spaced around the diametrically opposed leaf spring notches 108.
  • Outlet apertures 121 are axially aligned with outlet holes 120 in spool 10. Apertures 20, 111, 113, 117, 119, and 121 extend through sleeve 12.
  • STABILIZING MEANS Stabilizing means D comprises the slots 18 in spool 10 and orifices 16 and apertures 20 in sleeve 12 and more particularly the geometric configuration and relationship therebetween.
  • FIGS. 6, 8, 14, 15, and 16 there is shown a particular configuration of apertures 20 in sleeve membervl2. More particularly four elongated, relatively large charging apertures 128 are circumferentially spaced around sleeve member 12. Circumferentially spaced between charging apertures 128 is a first row 130 of eight circular apertures 132 of a given diameter J. Longitudinally spaced towards the bearing plate axial end 54 of sleeve 12 is a second row 134 of circumferentially spaced circular apertures 132; the apertures in the second row 134 axially align with the apertures in the first row 130.
  • each gain hole 136 in the third row 138 axially aligned with corresponding apertures 132 in the first and second rows 130, 134.
  • a fourth row 140 of gain holes 136 Longitudinally spaced from the third row 138 of gain holes is a fourth row 140 of gain holes 136 likewise circumferentially spaced so that each gain hole 136 in the fourth row 140 is axially aligned with a corresponding gain hole in a third row 138 and aperture in the first and second rows 130, 134.
  • each gain hole 136 Disposed above and below each gain hole 136 is the third and fourth row 138, 140 at a predetermined centerline distance L is an augmenting orifice 16; there thus being 16 orifices in the third row 138 and 16 orifices in the fourth row 140 with each orifice in the third row axially aligned with an orifice in the fourth row.
  • the gain holes 136 have diameters approximately half of the circular apertures 132 and the diameter of orifices 16 are equal to that of gain holes 136.
  • the centerline spacing L between each pair of axially aligned augmenting orifices 16 and each pair of axially aligned gain holes 136 in the third and fourth rows respectively 138, 140 is equal to an are extending 6% of the periphery of sleeve 12 in the embodiment shown.
  • FIGS. 5, 8, 14, 15, and 16 there is shown a plurality of slots 18 in a particular arrangement on spool member 10.
  • four circumferentially spaced charging slots 129 adapted to be in alignment with charging apertures 128 in sleeve 12 when controller A is in a neutral position.
  • Circumferentially spaced so as to be on each side of each charging slot 129 are 12 discontinuous pressure slots 131 which do not extend through spool 10.
  • Circumferentially spaced and interspersed between charging slots 129 are eight stability slots 133 adapted to be in communication with circular apertures 132 and gain holes 136 when the controller is in a neutral position.
  • each stability slot has a width at its bearing plate axial end which is equal to that of diameter J of circular apertures 132 in sleeve 12.
  • stability slot 133 has a width equal to diameter K of the gain holes 136 in sleeve 12.
  • valving passages 81 in tubular casing 14 will increase in pressure as valving slots 112 move into greater registry with valving apertures 113 as steering wheel 42 is moved beyond X
  • controller A is actuated. It should be noted that maximum communication between feed slots 112 and valving slots 114 with valving apertures 113 in the embodiment shown is established at 10 which is the angle that drive pin 102 is engaged by the circumferentially extended slot 103 in spool 10.
  • the degree of rotation of sleeve relative to spool is also a function of rate of steering wheel speed.
  • controller A As it moves from neutral to actuated position or vice-versa, it should be apparent thatwhen steering wheel 42 is slightly rotated X slots 18 in spool 10 will move X out of registry with the apertures 20 in sleeve 12. Similarly valving and feed slots 112,114 in spool 10 will move X into registry with valving apertures 113
  • the ratio of change in flow resistance to the change in relative rotation determines the sensitivity and stability of the system, and this ratio specifies the gain rate of the controller. Generally if the controller has a linear gain within the working rotational range, it will approach a stable valve. If not, the gain will fluctuate between maxima and minima in a short interval of rotation, causing instability in the valve.
  • FIG. 14 shows the alignment of slots, orifices, and apertures 18,16,20 with controller A in neutral position.
  • the total flow area A-1 communicating pressure from the pump inlet groove 76 through to passage 94 in spool 10 comprises the area A-1 of charging apertures 128 plus the area A2 of circular apertures 132 plus the area A-3 of gain holes 136.
  • the total area of all augmented orifices 16 on one side of gain holes 136 is equal to the area A-3 of gain holes 136.
  • augmented orifices 16 are not in communication with stability slots 133 in spool member 10.
  • relatively large charging apertures 128 and slots 129 in spool and sleeve members 10,12 are provided to permit relatively unimpeded flow through axial passage 94 in spool in neutral position.
  • gain holes 136 move out of registry with stability slots 133 at a faster rate than do circular apertures 128.
  • circular apertures 132 move out of register with stability slots 133 at a faster rate than do charging apertures and slots 128,129.
  • gain holes 136 have moved substantially out of registry with stabilizing slots 133, the circular apertures 132 have moved out of registry with stability slots 133 by approximately half of their area while charging aperture 128 have moved proportionately less out of engagement with charging slots 129.
  • the spacing L between axial pairs of augmenting orifices 16 and gain holes 136 is such that the orifices 16 have not moved into substantial engagement with stability slots 133 at this point. This condition makes the controller capable of steering the system. It should also be noted that area A-3 of gain holes 136 is so established that if the gain holes 136 were eliminated the flow area in neutral position as illustrated in FIG. 13 would be less, causing higher pressure drop.
  • the augmented orifices 16 disposed on one side of gain holes 136 come into registry with stability slots 133 as circular apertures 132 move further out of registry; the areas of orifices 16 and remaining areas of apertures 132 being such that the decreasing areas of apertures 132 is substantially compensated by the augmenting orifices 16. (See FIG. 15.)
  • the charging apertures 128 continue to move further out of contact with charging slots 129, with the total area decreasing but at a less rate than would occur if the augmenting orifices 16 were not present. This is illustrated in the graph shown in FIG. 13 of pressure change versus spool and sleeve deflection.
  • the dotted line 148 shown therein is the pressure change curve which would result if the augmenting orifices 16 were deleted from the controller while the solid line 150 shows a pressure change graph of the controller with augmenting orifices
  • a rotation of Y will produce a controller actuation point which will occur in the arrangement illustrated between 4 and 7 of relative movement between sleeve and spool members 10,12.
  • a controller with the invention would have a pressure change onethird as severe as a controller without the augmenting orifices 16.
  • FIG. 13 it is clear that the augmenting orifices tend to yield a better approximation to linearity over a wider range of valve deflection.
  • the gain rate of the valve is appreciably gradual when compared to a valve without augmenting orifices and hence the invention will lead to a comparatively stable valve without effecting the total rotation between sleeve and spool which is approximately 10 in the aforesaid valve.
  • a controller operatively connected to a servomotor for actuating a fluid pressure operated device, said controller comprising valve structure including a primary movable valve element and a cooperating movable follow-up valve element; means for connecting said primary valve element to a control element for common movements therewith; said fluid servomotor including a rotary member coupled to said follow-up element for imparting follow-up movements thereto responsive to rotation of said rotary member; said valve structure defining, an inlet for connection to a source of fluid under pressure and an outlet for return of fluid to said source, a pair of fluid ports for connection to a fluid pressure operated device, and fluid passages communicating with said servomotor; said valve elements each having valve passages which cooperate to direct flow of fluid from said inlet through said servomotor to one of said ports and to direct flow of fluid from the other of said ports to said outlet responsive to movement of said primary valve element in one direction away from a neutral position relative to said follow-up valve element; movement of said primary valve element in the opposite direction from said neutral position causing said
  • said follow-up valve element having at least a first row of a plurality of circumferentially spaced apertures and at least a second row of circumferentially spaced orifices longitudinally displaced from said first row, said orifices circumferentially oriented with respect to said apertures so that one orifice is disposed above and below each first aperture a predetermined distance, and said primary valve element having a plurality of circumferentially spaced slots of number equal to said apertures, each slot axially extending a distance at least equal to the distance from said first row to said second row, said apertures and said slots in communication with one another when said controller is unactuated.
  • a modulating controller for controlling fluid flow to a fluid pressure operated device comprising:
  • a casing having a cavity therein, an inlet extending into said cavity and first and second outlets extending from said cavity;
  • first and second valve members disposed in said cavity, said first and second valve members being relatively movable between a neutral and an actuated position;
  • said first and second valve members defining a first flow area through said valve members for providing a fluid flow path between said inlet and said first outlet when said valve members are in said neutral position;
  • said first and second members defining a second fluid flow area through said valve members for providing a second fluid flow path between said inlet and said second outlet when said valve members are in said actuated position, said first flow area being decreased a predetermined amount in said actuated position;
  • valve members a third flow area through said valve members, said third flow area being effective to modify the effective area of said first flow area during relative movement of said members between said neutral and actuated positions,
  • first and second valve members being sleeve and spool members respectively;
  • said sleeve member having a plurality of first apertures circumferentially spaced thereabout, said spool member having a like plurality of circumferentially spaced slots extending therethrough;
  • said first apertures being aligned with said slots to define first flow area, said apertures being movable out of registry with said slots to define said decreased first flow area; and 7 said third flow area being defined by a plurality of second aperatures in said sleeve member, said second aperatures being spaced circumferentially about said sleeve member a predetermined distance on each side of at least some of said first apertures;
  • said first apertures including a first plurality of generally circular apertures and a second plurality of larger charging apertures interspersed among said circular apertures, and said second apertures including a plurality of augmenting orifices;
  • said slots including a pluralityof longitudinally extending slots equal in number to said first plurality and having a width at one end approximately equal to the size of said augmenting orifices and a width at the other end approximately equal to the size of said first apertures and a plurality of charging slots equal in number to said second plurality and having a width approximately equal to that of said charging apertures.
  • a controller operatively connected to a servomotor for actuating a fluid pressure. device comprising:
  • a casing having an opening therein and at least an inlet and outlet vport communicating with said opening;
  • passage means in said sleeve and spool member to direct fluid into said servomotor when said controller is actuated
  • control means in said spool and sleeve members to direct fluid pressure from said inlet through said spool to said outlet when said controller is in a neutral position andto change fluid pressure direction through said spool member when said controller is actuated;
  • control means further including said sleeve member having at least a first row of a plurality of circumferentially spaced first apertures and at least a second row of circumferentially spaced orifices longitudinally displaced from said first row, said orifices circumferentially orientated with respect to said apertures so that an orifice is disposed above and below each first aperture a predetermined distance, and said spool member having a plurality of circumferentially spaced slots of a number equal to said first apertures and in circumferentially aligned relationship with said first apertures, each of said slots axially extending a distance at least equal to the distance from said first row to said second row, said first apertures and slots in alignment with one another when said controller is in a neutral position.
  • a controller as defined in claim 3 wherein said pre determined distance is sufiicient to communicate an increasing area of said orifices with said slots after said first apertures have rotated a portion of their area out of communication with said slots as said spool and valve members rotate relative to each other.
  • a controller as defined in claim 6 further including a plurality of axially-extending, discontinuous grooves in the exterior surface of said spool member interspersed between said first slots and in at least partial communication with at least some of said first apertures when said controller is actuated.
  • each gain hole and each orifice have substantially equal areas.
  • said sleeve member has a third row of first apertures of like number of said apertures in said first row, said apertures in said third row circumferentially orientated with respect to said first apertures in said first row to be axially aligned therewith, said third row longitudinally spaced from said first row in a direction away from said second row of orifices, and said first slots in said spool member extending to said third row.
  • a controller as defined in claim 10 wherein said sleeve member has a fourth row of said orifices and said gain holes circumferentially spaced and aligned so that each orifice and gain hole in said fourth row is axially aligned with a corresponding orifice and gain hole in said second row, said fourth row longitudinally spaced from said second row away from said first and third rows and each of said slots in said spool member has a width at one axial end substantially equal to said first aperture and a width at the opposing axial end substantially equal to the diameter of said gain holes and a length extending to said fourth row, each of said slots in commmunication with said first apertures and gain holes when said controller is in an unactuated position.
  • a controller for a fluid pressure operated device comprising:
  • a housing secured to said servomotor and having a generally cylindrical opening therein;
  • a fluid inlet a fluid outlet and first and second selectively pressurizable ports in said housing communicating with said opening, said first and second ports being adapted to be connected in fluid communication with said fluid operated device;
  • a sleeve member rotatably disposed within said opena spool member disposed within said sleeve member and mounted for limited rotary movement relative to said sleeve member;
  • flow passage means in said spool and sleeve members operable to provide fluid communication from said inlet through said spool and sleeve members to said outlet when said controller is in a neutral position and to change fluid pressure direction through said spool member when said controller is actuated to provide fluid communication between said inlet and said servomotor and from said servomotor to one of said first and second ports;
  • first pressure balancing means operable to maintain said sleeve member centrally disposed within said opening
  • second pressure balancing means operable to maintain said spool member centrally disposed within said sleeve member, said second pressure balancing means including said sleeve and spool members defining first and second balancing areas, said first and second balancing areas being in communication with fluid under high pressure from said inlet when said spool is displaced relative to said sleeve upon actuation of said controller;
  • said first area being defined by first and second peripheral grooves in said spool member axially spaced from one another, and a plurality of axially extending, discontinuous, circumferentially spaced recesses in said spool member, each recess communicating with said first and second peripheral grooves and extending a sufficient distance to be axially aligned with said first and second ports and in communication with one of said first and second ports when said controller is actuated.
  • said second area in said spool member defined by longitudinally extending, discontinuous balancing slots axially aligned with said apertures, said apertures being out of fluid communication with said slots when said controller is in its nonnal position and in fluid communication with said apertures when said spool is displaced relative said sleeve upon actuation of said controller.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Steering Control In Accordance With Driving Conditions (AREA)
  • Power Steering Mechanism (AREA)
  • Servomotors (AREA)
US30003772 1972-10-24 1972-10-24 Stability means for a controller for fluid pressure operated devices Expired - Lifetime US3819307A (en)

Priority Applications (10)

Application Number Priority Date Filing Date Title
US30003772 US3819307A (en) 1972-10-24 1972-10-24 Stability means for a controller for fluid pressure operated devices
CA183,886A CA962550A (en) 1972-10-24 1973-10-22 Stability means for a controller for fluid pressure operated devices
AU61714/73A AU471180B2 (en) 1972-10-24 1973-10-23 Stability means for a controller for fluid pressure operated devices
DE19732353068 DE2353068A1 (de) 1972-10-24 1973-10-23 Steuergeraet fuer druckmittelbetaetigte vorrichtungen
IT3047573A IT998896B (it) 1972-10-24 1973-10-23 Mezzo stabilizzatore per un dispositivo di controllo previsto per dispositivi azionati dalla pressione di un fluido
FR7337963A FR2203953A1 (enrdf_load_stackoverflow) 1972-10-24 1973-10-24
JP11978473A JPS4994028A (enrdf_load_stackoverflow) 1972-10-24 1973-10-24
BR832073A BR7308320D0 (pt) 1972-10-24 1973-10-24 Controlador modulador aperfeicoado
GB4960273A GB1444019A (en) 1972-10-24 1973-10-24 Stability means for a controller for fluid pressure operated de vices
GB4804875A GB1444020A (en) 1972-10-24 1973-10-24 Controller for fluid pressure operated devices

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US30003772 US3819307A (en) 1972-10-24 1972-10-24 Stability means for a controller for fluid pressure operated devices

Publications (1)

Publication Number Publication Date
US3819307A true US3819307A (en) 1974-06-25

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ID=23157418

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Application Number Title Priority Date Filing Date
US30003772 Expired - Lifetime US3819307A (en) 1972-10-24 1972-10-24 Stability means for a controller for fluid pressure operated devices

Country Status (9)

Country Link
US (1) US3819307A (enrdf_load_stackoverflow)
JP (1) JPS4994028A (enrdf_load_stackoverflow)
AU (1) AU471180B2 (enrdf_load_stackoverflow)
BR (1) BR7308320D0 (enrdf_load_stackoverflow)
CA (1) CA962550A (enrdf_load_stackoverflow)
DE (1) DE2353068A1 (enrdf_load_stackoverflow)
FR (1) FR2203953A1 (enrdf_load_stackoverflow)
GB (2) GB1444019A (enrdf_load_stackoverflow)
IT (1) IT998896B (enrdf_load_stackoverflow)

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4033377A (en) * 1974-09-18 1977-07-05 Eaton Corporation Controller for fluid pressure operated devices
DE2737788A1 (de) * 1976-08-24 1978-03-02 Eaton Corp Steuergeraet mit geschlossener mittelstellung
US4109679A (en) * 1976-04-23 1978-08-29 Eaton Corporation Controller for fluid pressure operated devices
US4251194A (en) * 1978-04-03 1981-02-17 Danvoss A/S Spring arrangement for the control valve of a hydrostatic steering unit
US4336687A (en) * 1980-04-21 1982-06-29 Eaton Corporation Load sensing controller
US4395877A (en) * 1979-02-17 1983-08-02 Zahnradfabrik Friedrichshafen, Ag. Hydrostatic steering system for motor vehicles
US4462774A (en) * 1982-09-27 1984-07-31 William Hotine Rotary expander fluid pressure device
US4671747A (en) * 1985-02-14 1987-06-09 Danfoss A/S Control device for hydrostatic power assisted steering
US4934911A (en) * 1987-04-01 1990-06-19 Mannesmann Rexroth Gmbh Hydraulic rotary piston engine having inproved commutator valve
US5080135A (en) * 1990-10-24 1992-01-14 Eaton Corporation Large deflection angle rotary modulation steering valve
DE4107604A1 (de) * 1991-03-09 1992-09-10 Danfoss As Vollhydraulische lenkeinheit
US5161577A (en) * 1990-04-23 1992-11-10 Eaton Corporation Fluid controller having rotary/axial valving, and spring arrangement therefor
US6427722B1 (en) * 2000-05-23 2002-08-06 Danfoss Fluid Power A/S Rotary slide set for a hydraulic steering arrangement
US20030217550A1 (en) * 2002-05-27 2003-11-27 Ognibene S.P.A. Hydrostatic power steering device for fast steering
US20070113905A1 (en) * 2005-06-10 2007-05-24 Sauer-Danfoss Aps Fluid controller
US20090218161A1 (en) * 2008-02-28 2009-09-03 Eaton Corporation Control Valve Assembly for Electro-Hydraulic Steering System
US20110197983A1 (en) * 2008-05-02 2011-08-18 Eaton Corporation Isolation Valve for a Load-Reaction Steering System
US20120103444A1 (en) * 2010-11-03 2012-05-03 Sauer-Danfoss Aps Control device for a hydrostatic steering motor
US20130220458A1 (en) * 2012-02-28 2013-08-29 Ognibene Power S.P.A. Distributor device for hydraulic power steering
WO2014066592A1 (en) * 2012-10-24 2014-05-01 David Paul Smith Electro-hydraulic pressure reducing and relieving valve with flow force control for large flow capacity
CN104024088A (zh) * 2011-12-27 2014-09-03 丹佛斯动力系统有限公司 液压转向设备
US9927037B2 (en) * 2014-07-24 2018-03-27 Boston Dynamics, Inc. Rotary valve with brake mode
CN113371063A (zh) * 2020-03-10 2021-09-10 丹佛斯动力系统有限公司 液压转向单元
CN113374753A (zh) * 2020-03-10 2021-09-10 丹佛斯动力系统有限公司 尤其作为液压转向单元的一部分的流体控制器
CN113562069A (zh) * 2021-07-14 2021-10-29 芜湖中意液压科技股份有限责任公司 一种分体式前盖螺纹连接的全液压转向器
US12012160B2 (en) 2020-03-10 2024-06-18 Danfoss Power Solutions Aps Fluid controller, in particular as part of a hydraulic steering unit

Families Citing this family (19)

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Publication number Priority date Publication date Assignee Title
US3895888A (en) * 1973-10-19 1975-07-22 Trw Inc Hydrostatic control unit
US3960234A (en) * 1974-09-18 1976-06-01 Eaton Corporation Controller for fluid pressure operated devices providing high pressure to an auxiliary device
GB1524707A (en) * 1974-09-18 1978-09-13 Eaton Corp Controller for fluid pressure operated devices
HU170933B (hu) * 1975-04-01 1977-10-28 Autoipari Kutato Intezet Hhelevoe upravlenie k servorulevomu mekhanizmu avtomashin
IT1077304B (it) * 1976-06-23 1985-05-04 Eaton Corp Regolatore per dispositivi azionati dalla pressione di un fluido
DE2633011C3 (de) * 1976-07-22 1979-07-26 Zahnradfabrik Friedrichshafen Ag, 7990 Friedrichshafen Hydrostatische Hilfskraftlenkung, insbesondere für Kraftfahrzeuge
CA1059440A (en) * 1977-01-24 1979-07-31 Oliver W. Johnson Controller for fluid pressure operated devices
DE2917298C2 (de) * 1979-04-28 1985-03-21 Zahnradfabrik Friedrichshafen Ag, 7990 Friedrichshafen Drehschiebereinrichtung zur Steuerung eines hydrostatischen Servoantriebs
DE2917435C2 (de) * 1979-04-28 1987-03-12 Zahnradfabrik Friedrichshafen Ag, 7990 Friedrichshafen Drehschiebereinrichtung zur Steuerung eines hydrostatischen Servoantriebs
DE2944883C2 (de) * 1979-11-07 1982-08-26 Danfoss A/S, 6430 Nordborg Hydrostatische Lenkeinrichtung
DE2952674C2 (de) * 1979-12-28 1983-03-24 Danfoss A/S, 6430 Nordborg Hydraulische Lenkeinrichtung
DE3126040C2 (de) * 1981-07-02 1985-12-12 Danfoss A/S, Nordborg Hydraulische Steuervorrichtung
DE3302001C2 (de) * 1983-01-21 1985-05-09 Danfoss A/S, Nordborg Drehschieber für eine hydrostatische Lenkeinheit für Fahrzeuge
GB2144379B (en) * 1983-08-05 1987-05-20 Cam Gears Ltd Power steering valve and method of making the same
DE3789189T2 (de) * 1986-10-10 1994-06-01 Eaton Corp Flüssigkeitssteuerung und gedämpfter Flüssigkeitsweg.
JP2532079B2 (ja) * 1987-01-30 1996-09-11 日産自動車株式会社 パワ−ステアリング用ロ−タリ制御弁
US4862690A (en) * 1988-10-06 1989-09-05 Eaton Corporation Steering control unit with both flow amplification and manual steering capability
DE4204336C2 (de) * 1992-02-14 1995-07-06 Hydraulik Nord Gmbh Hydrostatische Lenkeinrichtung
IT1306089B1 (it) * 1998-07-31 2001-05-29 Ognibene Spa Distributore rotante a strozzatura variabile particolarmente perservosterzi o guide idrostatiche

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US3443586A (en) * 1966-06-07 1969-05-13 Danfoss As Four-way change-over device for hydraulic installations
US3528521A (en) * 1968-06-13 1970-09-15 Allis Chalmers Mfg Co Hydraulic steering system
US3564848A (en) * 1968-05-03 1971-02-23 Danfoss As Steering equipment particularly for heavy vehicles
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US3443586A (en) * 1966-06-07 1969-05-13 Danfoss As Four-way change-over device for hydraulic installations
US3564848A (en) * 1968-05-03 1971-02-23 Danfoss As Steering equipment particularly for heavy vehicles
US3584985A (en) * 1968-05-11 1971-06-15 Danfoss As Hydrostatic control equipment particularly for steering systems
US3528521A (en) * 1968-06-13 1970-09-15 Allis Chalmers Mfg Co Hydraulic steering system

Cited By (43)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4033377A (en) * 1974-09-18 1977-07-05 Eaton Corporation Controller for fluid pressure operated devices
US4109679A (en) * 1976-04-23 1978-08-29 Eaton Corporation Controller for fluid pressure operated devices
DE2737788A1 (de) * 1976-08-24 1978-03-02 Eaton Corp Steuergeraet mit geschlossener mittelstellung
US4251194A (en) * 1978-04-03 1981-02-17 Danvoss A/S Spring arrangement for the control valve of a hydrostatic steering unit
US4395877A (en) * 1979-02-17 1983-08-02 Zahnradfabrik Friedrichshafen, Ag. Hydrostatic steering system for motor vehicles
US4336687A (en) * 1980-04-21 1982-06-29 Eaton Corporation Load sensing controller
US4462774A (en) * 1982-09-27 1984-07-31 William Hotine Rotary expander fluid pressure device
US4671747A (en) * 1985-02-14 1987-06-09 Danfoss A/S Control device for hydrostatic power assisted steering
US4934911A (en) * 1987-04-01 1990-06-19 Mannesmann Rexroth Gmbh Hydraulic rotary piston engine having inproved commutator valve
US5161577A (en) * 1990-04-23 1992-11-10 Eaton Corporation Fluid controller having rotary/axial valving, and spring arrangement therefor
US5080135A (en) * 1990-10-24 1992-01-14 Eaton Corporation Large deflection angle rotary modulation steering valve
EP0482440A1 (en) * 1990-10-24 1992-04-29 Eaton Corporation Large deflection angle rotary modulation steering valve
DE4107604A1 (de) * 1991-03-09 1992-09-10 Danfoss As Vollhydraulische lenkeinheit
US5165447A (en) * 1991-03-09 1992-11-24 Danfoss A/S Fully-hydraulic steering unit
JP2500219B2 (ja) 1991-03-09 1996-05-29 ダンフォス アクチェセルスカベト 完全液圧操舵装置
US6427722B1 (en) * 2000-05-23 2002-08-06 Danfoss Fluid Power A/S Rotary slide set for a hydraulic steering arrangement
US20030217550A1 (en) * 2002-05-27 2003-11-27 Ognibene S.P.A. Hydrostatic power steering device for fast steering
US6863147B2 (en) * 2002-05-27 2005-03-08 Ognibene S.P.A. Hydrostatic power steering device for fast steering
US7610935B2 (en) * 2005-06-10 2009-11-03 Sauer-Danfoss Aps Fluid controller
US20070113905A1 (en) * 2005-06-10 2007-05-24 Sauer-Danfoss Aps Fluid controller
US7984785B2 (en) 2008-02-28 2011-07-26 Eaton Corporation Control valve assembly for electro-hydraulic steering system
US8651225B2 (en) 2008-02-28 2014-02-18 Eaton Corporation Control valve assembly for electro-hydraulic steering system
US20090218161A1 (en) * 2008-02-28 2009-09-03 Eaton Corporation Control Valve Assembly for Electro-Hydraulic Steering System
US20110197983A1 (en) * 2008-05-02 2011-08-18 Eaton Corporation Isolation Valve for a Load-Reaction Steering System
US8272471B2 (en) 2008-05-02 2012-09-25 Eaton Corporation Isolation valve for a load-reaction steering system
US20120103444A1 (en) * 2010-11-03 2012-05-03 Sauer-Danfoss Aps Control device for a hydrostatic steering motor
CN102556154A (zh) * 2010-11-03 2012-07-11 索尔-丹佛斯公司 用于静液力转向马达的控制装置
CN102556154B (zh) * 2010-11-03 2015-06-17 丹佛斯动力系统有限公司 用于静液力转向马达的控制装置
US8561643B2 (en) * 2010-11-03 2013-10-22 Sauer-Danfoss Aps Control device for a hydrostatic steering motor
CN104024088A (zh) * 2011-12-27 2014-09-03 丹佛斯动力系统有限公司 液压转向设备
US9032999B2 (en) * 2012-02-28 2015-05-19 Ognibene Power S.P.A. Distributor device for hydraulic power steering
US20130220458A1 (en) * 2012-02-28 2013-08-29 Ognibene Power S.P.A. Distributor device for hydraulic power steering
WO2014066592A1 (en) * 2012-10-24 2014-05-01 David Paul Smith Electro-hydraulic pressure reducing and relieving valve with flow force control for large flow capacity
CN104813038A (zh) * 2012-10-24 2015-07-29 大卫·保罗·史密斯 用于大流量容量具有流动力控制的电液减压和泄压阀
US10648575B2 (en) 2012-10-24 2020-05-12 Prince Industries, Inc. Electro-hydraulic pressure reducing and relieving valve with flow force control for large flow capacity
US9927037B2 (en) * 2014-07-24 2018-03-27 Boston Dynamics, Inc. Rotary valve with brake mode
CN113371063A (zh) * 2020-03-10 2021-09-10 丹佛斯动力系统有限公司 液压转向单元
CN113374753A (zh) * 2020-03-10 2021-09-10 丹佛斯动力系统有限公司 尤其作为液压转向单元的一部分的流体控制器
US11623684B2 (en) * 2020-03-10 2023-04-11 Danfoss Power Solutions Aps Hydraulic steering unit
CN113374753B (zh) * 2020-03-10 2023-11-21 丹佛斯动力系统有限公司 尤其作为液压转向单元的一部分的流体控制器
US11878748B2 (en) 2020-03-10 2024-01-23 Danfoss Power Solutions Aps Fluid controller, in particular as part of a hydraulic steering unit
US12012160B2 (en) 2020-03-10 2024-06-18 Danfoss Power Solutions Aps Fluid controller, in particular as part of a hydraulic steering unit
CN113562069A (zh) * 2021-07-14 2021-10-29 芜湖中意液压科技股份有限责任公司 一种分体式前盖螺纹连接的全液压转向器

Also Published As

Publication number Publication date
AU471180B2 (en) 1976-04-08
JPS4994028A (enrdf_load_stackoverflow) 1974-09-06
GB1444019A (en) 1976-07-28
DE2353068A1 (de) 1974-05-02
GB1444020A (en) 1976-07-28
IT998896B (it) 1976-02-20
AU6171473A (en) 1975-04-24
FR2203953A1 (enrdf_load_stackoverflow) 1974-05-17
BR7308320D0 (pt) 1974-08-22
CA962550A (en) 1975-02-11

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