US3729026A — Control valve with metering type valve spool

Claim 1

Independent Claim 244 words

A control valve having a valve spool with alternately spaced grooves and lands, and a bore in which the spool is slidable from one to the other of a pair of metering positions in the former of which it provides for restricted flow of supply fluid concurrently along first and second paths leading through spaced zones of the bore and through throttle notches in the ends of certain of said lands, one of said paths leading from upstream to downstream branches of a fluid supply passage and the second one of said paths leading to a service passage, said spool being operable in the other of said metering positions thereof to provide for restricted flow of return fluid to a tank passage along a third path leading through the bore from the service passage and extending through similar throtTle notches in the end of one of said lands, characterized by: A. an arrangement of passages, lands, and throttle notches such that in each metering position of the spool fluid travelling along each of said paths is constrained to flow through the throttle notches thereof before such fluid enters the bore; B. and each of said throttle notches having a bottom wall which faces toward the periphery of the spool and diverges at a small acute angle away from the spool axis toward the adjacent spool groove, and a concave side wall which faces toward the adjacent groove and is normal to said bottom wall.

Claim 2

Dependent Claim 244 words

A control valve having a valve spool with alternately spaced grooves and lands, and a bore in which the spool is slidable from one to the other of a pair of metering positions in the former of which it provides for restricted flow of supply fluid concurrently along first and second paths leading through spaced zones of the bore and through throttle notches in the ends of certain of said lands, one of said paths leading from upstream to downstream branches of a fluid supply passage and the second one of said paths leading to a service passage, said spool being operable in the other of said metering positions thereof to provide for restricted flow of return fluid to a tank passage along a third path leading through the bore from the service passage and extending through similar throtTle notches in the end of one of said lands, characterized by: A. an arrangement of passages, lands, and throttle notches such that in each metering position of the spool fluid travelling along each of said paths is constrained to flow through the throttle notches thereof before such fluid enters the bore; B. and each of said throttle notches having a bottom wall which faces toward the periphery of the spool and diverges at a small acute angle away from the spool axis toward the adjacent spool groove, and a concave side wall which faces toward the adjacent groove and is normal to said bottom wall.

Claim 3

Dependent Claim 146 words

The control valve of claim 1, further characterized by: A. said valve spool being operable in both of its said metering positions to provide restricted communication between upstream and downstream branches of the supply passage via the bore and throttle notches of said configuration in the spool at one end of each of a pair of said grooves; B. said valve having a second service passage; C. the valve spool being operable in said metering positions thereof to restrictedly direct supply fluid to a selected one of said service passages and to restrictedly communicate the non-selected service passage with a tank passage, all via the bore and throttle notches of said configuration in the spool lands; D. and said passages, lands and throttle notches being so arranged as to constrain pressure fluid flowing through all of said throttle notches to pass therethrough before entering the bore.

Claim 4

Dependent Claim 30 words

and operable in said other working position of the spool to provide for flow to the second service passage of pressure fluid debouching from the fourth set of throttle notches.

Claim 5

Dependent Claim 30 words

and operable in said other working position of the spool to provide for flow to the second service passage of pressure fluid debouching from the fourth set of throttle notches.

Claim 6

Dependent Claim 34 words

and operable in the other of said working positions of the spool to provide for flow to said tank passage of return fluid debouching into the bore from the second set of throttle notches.

Claim 7

Dependent Claim 34 words

and operable in the other of said working positions of the spool to provide for flow to said tank passage of return fluid debouching into the bore from the second set of throttle notches.

Claim 8

Dependent Claim 18 words

and a concave sIde wall which is substantially normal to said bottom wall; E. and passage defining means

Claim 9

Dependent Claim 18 words

and a concave sIde wall which is substantially normal to said bottom wall; E. and passage defining means

Claim 10

Dependent Claim 13 words

and a concave side wall which is substantially normal to said bottom wall.

Claim 11

Dependent Claim 13 words

and a concave side wall which is substantially normal to said bottom wall.

Claim 12

Dependent Claim 45 words

The control valve of claim 2, wherein the side wall of each throttle notch is cylindrically surfaced and concentric to an axis which intersects that of the spool and recedes at a substantially small acute angle from said adjacent groove outwardly of the spool axis.

Claim 13

Dependent Claim 151 words

A control valve having a bore with a valve spool slidable axially therein and having spaced grooves and lands with throttle notches in their ends to limit flow of pressure fluid to a service passage and from upstream to downstream branches of a supply passage through the bore in a first metering position of the spool, and to limit flow of return fluid through the bore to a tank passage from said service passage in a second metering position of the spool, said control valve being characterized by: A. passages, lands and throttle notches such that wherever fluid flows from one passage to another via the bore and throttle notches in one of said lands, such fluid is constrained to travel through the throttle notches before entering the bore; B. and each of said throttle notches opening to one of said grooves and to the periphery of its land, and having

Claim 14

Dependent Claim 151 words

A control valve having a bore with a valve spool slidable axially therein and having spaced grooves and lands with throttle notches in their ends to limit flow of pressure fluid to a service passage and from upstream to downstream branches of a supply passage through the bore in a first metering position of the spool, and to limit flow of return fluid through the bore to a tank passage from said service passage in a second metering position of the spool, said control valve being characterized by: A. passages, lands and throttle notches such that wherever fluid flows from one passage to another via the bore and throttle notches in one of said lands, such fluid is constrained to travel through the throttle notches before entering the bore; B. and each of said throttle notches opening to one of said grooves and to the periphery of its land, and having

Claim 15

Dependent Claim 162 words

A control valve having a bore to which service, feeder and tank passages open, and a valve spool which is slidable axially in the bore from a neutral position to each of a pair of working positions to communicate the service passage with either the feeder passage or with a tank passage, characterized by the following: A. grooves in the spool defining axially spaced lands thereon; B. a first set of throttle notches in an end of one of said lands through which fluid can flow to the bore from the feeder passage in one of said working positions of the valve spool; C. a second set of throttle notches in an end of one of said lands through which fluid can flow to the bore from the service passage in the other of said working positions of the valve spool; D. each of said throttle notches opening to one of said grooves and to the periphery of its land and having

Claim 16

Dependent Claim 162 words

A control valve having a bore to which service, feeder and tank passages open, and a valve spool which is slidable axially in the bore from a neutral position to each of a pair of working positions to communicate the service passage with either the feeder passage or with a tank passage, characterized by the following: A. grooves in the spool defining axially spaced lands thereon; B. a first set of throttle notches in an end of one of said lands through which fluid can flow to the bore from the feeder passage in one of said working positions of the valve spool; C. a second set of throttle notches in an end of one of said lands through which fluid can flow to the bore from the service passage in the other of said working positions of the valve spool; D. each of said throttle notches opening to one of said grooves and to the periphery of its land and having

Claim 17

Dependent Claim 113 words

The control valve of claim 5 further characterized by: A. a supply passage in the valve having upstream and downstream branches which open to the bore at axially spaced zones; B. said grooves defining a land on the spool having an end portion which is carried into the bore between said zones to thereby restrict communication between said branches when the spool is moved to said one operating position thereof; C. and throttle notches of said configuration in said end portion of the last named land, through which fluid must flow from the upstream to the downstream branches of the supply passage along a path leading serially through the notches and the bore.

Claim 18

Dependent Claim 82 words

The control valve of claim 5, further characterized by: A. said service passage opening to the bore at a location between the junctions of the bore with the feeder and tank passages; B. and said passage defining means comprising a passageway having one end in communication with the service passage and its other end communicated with the bore at a zone near the junction of the bore and feeder passage and at the side of the latter remote from the service passage.

Claim 19

Dependent Claim 113 words

The control valve of claim 7, further characterized by: A. a supply passage in the valve having upstream and downstream branches which open to the bore at axially spaced zones; B. said grooves defining a land on the spool having an end portion which is carried into the bore between said zones to thereby restrict communication between said branches when the spool is moved to said one operating position thereof; C. and throttle notches of said configuration in said end portion of the last named land, through which fluid must flow from the upstream to the downstream branches of the supply passage along a path leading serially through the notches and the bore.

Claim 20

Dependent Claim 89 words

The control valve of claim 5, further characterized by: A. said service passage opening to the bore at a first zone; B. the feeder and tank passages opening to the bore at second and third zones, respectively, at opposite sides of said first zone; C. and said passage defining means comprising a passageway having one end in communication with the bore at a location between said first and second zones, and having its other end in communication with the bore at a location between said first and third zones.

Claim 21

Dependent Claim 113 words

The control valve of claim 9, further characterized by: A. a supply passage in the valve having upstream and downstream branches which open to the bore at axially spaced zones; B. said grooves defining a land on the spool having an end portion which is carried into the bore between said zones to thereby restrict communication between said branches when the spool is moved to said one operating position thereof; C. and throttle notches of said configuration in said end portion of the last named land, through which fluid must flow from the upstream to the downstream branches of the supply passage along a path leading serially through the notches and the bore.

Claim 22

Dependent Claim 149 words

The control valve of claim 5, further characterized by: A. a second set of service, feeder and tank passages which open to the bore at axially spaced locations; B. the second service passage being communicable with the second tank passage by the valve spool in said one working position thereof, and being communicable with the second feeder passage by the spool in said other working position thereof; C. a thIrd set of said throttle notches in an end of one of said lands, through which fluid can flow to the bore from the second service passage in said one working position of the spool; D. a fourth set of said throttle notches in an end of one of said lands, through which fluid can flow to the bore from the second feeder passage in the other of said working positions of the spool; E. and other passage defining means

Claim 23

Dependent Claim 89 words

The control valve of claim 11, further charactaerized by: A. a supply passage having a center upstream branch and flanking downstream branches; and B. land members on the spool to govern communication between said supply passage branches, including a single land which is normally centered with respect to the upstream branch of the supply passage and has throttle notches of said configuration in its opposite ends to restrict flow into the bore from the upstream supply passage branch upon movement of the spool toward either of its working positions.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1976-04-23	1976-10-23	1977-04-24	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1980-04-23	1980-10-23	1981-04-24	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1984-04-23	1984-10-23	1985-04-24	$7700.00	Window Closed / Lapsed

Control valve with metering type valve spool

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