Rotary spool valve

Claim 2

A four-way valve comprising: A. a valve body having a cylindrical valve chamber, a discharge port connecting with one end of said chamber, and facing into said chamber on the cylindrical wall thereof, an inlet port and opposed right and left operating ports, said operating ports being disposed 90* around said wall on each side of said inlet port, and B. a cylindrical spool mating with and fitting within said chamber and adapted for rotation therein; said spool having an inlet set of three longitudinal slots in the periphery thereof facing said wall and commonly interconnected by a passageway, said slots when viewed in a cross section of said spool being offset in a Y configuration with the arm-slots being 90* apart and the leg-slot bisecting the outside angle of said arm slots, the area of contact afforded by said leg slot with the cylindrical wall of said valve chamber being so proportioned with respect to the areas of contact afforded by the arm-slots that the displacing forces created by each are balanced; said spool also having at least two discharge openings in the periphery thereof which discharge openings when viewed in a cross section of said spool are disposed 45* on each side of said leg-slot, said discharge openings being adapted to register with said operating ports and being commonly interconnected and connected with said discharge port by a discharge passageway; and said spool fitting into said valve body and said slots and openings being disposed such that when said spool is rotated to be in the a. mid position, none of said slots and openings register with any of said ports; b. right feed position, one arm-slot of said inlet set registers with said inlet port and the other arm-slot thereof with said right-operating port, and one of said discharge openings registers with said left-operating port; and c. left-feed position, the other arm-slot of said inlet set registers with said inlet port and said one arm-slot with said left operating port, and the other of said discharge openings registers with said right-operating port.

Claim 3

The valve of claim 1 wherein a cylindrical valve stem extends from one end of said spool along the axis of rotation thereof through said valve body and a seal against fluid leakage is maintained therebetween.

Claim 4

The valve of claim 1 wherein there are three of said discharge openings on the periphery of said spool, the center lines of which intersect in a Y configuration and all commonly interconnected by said discharge passageway, the Y of said inlet slots being disposed 180* to the Y of said discharge openings, and the leg opening of said discharge oPenings when said spool is in said mid position registering with said inlet port and allowing fluid to bypass to said discharge port.

Claim 5

The valve of claim 3 when ganged with another of said valves side-by-side along the axis of revolution of said spool, therebeing but a single valve body with but a single common inlet port, discharge port and a single common spool having only said sets of slots and discharge opening and two sets of said operating ports, longitudinally offset one from the other, said spool being longitudinally movable from a mid position in either direction and rotated to effect operation of one or the other of said sets of operating ports.

Claim 6

A sliding and rotary spool valve comprising: a valve body having a cylindrical bore, a discharge port at one end thereof, and inlet port and a pair of opposed operating ports disposed 90* on either side thereof, all three ports opening into the mid portion of said cylindrical bore, and a take-off port with a check valve therein between said mid portion and said discharge port, said check valve being normally closed to flow into said cyindrical bore, said cylindrical bore having a valve seat between said take-off port and said discharge port; a spool mating and fitting within said bore and adapted for axial and rotary motion therein, said spool having a straight cylindrical first section in the area of said mid portion and having at the end facing said discharge port a shoulder tapering to a straight cylindrical second section of smaller diameter than the first and ending in a annular lip, said lip being downstream of said valve seat and being adapted to form a discharge valve therewith; said first section having a bypass passageway adapted to transmit fluid from said inlet port to the area of said second section when said spool is in a closed position and having axially disposed peripheral passageways therein, one side of which opens to said cyindrical bore, arranged in two sets, an inlet set of three passageways and a discharge set of at least two passageways, said inlet set when viewed in a cross section of said spool being arranged in a Y configuration thereabout with the leg passageway registering with said inlet port when said spool is in a 0* mid position, and the arm passageways of said inlet set being 90* apart with the leg passageway bisecting the outside angle therebetween; the ends of said inlet set terminating within said first section and being interconnected by a common passageway, and the area of the leg passageway of said inlet set contacting said cylindrical bore being about two-thirds of the combined areas of the arm passageways so contacting said cyilndrical bore; and two of said discharge passageways being disposed 45* on either side of said leg passageway and freely communicating with said discharge port when said spool is in a position other than its closed position; said check valve facing said second section when said spool is in its mid axial position and being adapted to being opened by fluid pressure from within the valve and by engagement with said shoulder; the disposition of said ports and passageways being such that when said valve is operated with at all times said leg passageway of said inlet set not registering with any of said ports, and placed in a 0* rotation position with neither of said operating ports registering with any of said passageways and a. an axial mid position, said discharge port is open and said check valve is closed, b. an axial closed position, said discharge valve is closed, said inlet port introduces fluid into the zone of said second section through said bypass passageway and the pressure thereof causes said check valve to open, and c. axial open position, said discharge port is open and said shoulder engages said check valve, opening the same; 45* rotation in either direction, said check valve remaining closed and said discharge valve remaining opeN, a leg passageway of said inlet set registers with said inlet port and the other leg passageway registers with one of said operating ports, and one of said discharge passageways registers with the other of said operating ports.

Claim 7

A sliding and rotary spool valve comprising: a valve body having a cylindrical bore, a discharge port at one end thereof, and inlet port and a pair of opposed operating ports disposed 90* on either side thereof, all three ports opening into the mid portion of said cylindrical bore, and a take-off port with a check valve therein between said mid portion and said discharge port, said check valve being normally closed to flow into said cyindrical bore, said cylindrical bore having a valve seat between said take-off port and said discharge port; a spool mating and fitting within said bore and adapted for axial and rotary motion therein, said spool having a straight cylindrical first section in the area of said mid portion and having at the end facing said discharge port a shoulder tapering to a straight cylindrical second section of smaller diameter than the first and ending in a annular lip, said lip being downstream of said valve seat and being adapted to form a discharge valve therewith; said first section having a bypass passageway adapted to transmit fluid from said inlet port to the area of said second section when said spool is in a closed position and having axially disposed peripheral passageways therein, one side of which opens to said cyindrical bore, arranged in two sets, an inlet set of three passageways and a discharge set of at least two passageways, said inlet set when viewed in a cross section of said spool being arranged in a Y configuration thereabout with the leg passageway registering with said inlet port when said spool is in a 0* mid position, and the arm passageways of said inlet set being 90* apart with the leg passageway bisecting the outside angle therebetween; the ends of said inlet set terminating within said first section and being interconnected by a common passageway, and the area of the leg passageway of said inlet set contacting said cylindrical bore being about two-thirds of the combined areas of the arm passageways so contacting said cyilndrical bore; and two of said discharge passageways being disposed 45* on either side of said leg passageway and freely communicating with said discharge port when said spool is in a position other than its closed position; said check valve facing said second section when said spool is in its mid axial position and being adapted to being opened by fluid pressure from within the valve and by engagement with said shoulder; the disposition of said ports and passageways being such that when said valve is operated with at all times said leg passageway of said inlet set not registering with any of said ports, and placed in a 0* rotation position with neither of said operating ports registering with any of said passageways and a. an axial mid position, said discharge port is open and said check valve is closed, b. an axial closed position, said discharge valve is closed, said inlet port introduces fluid into the zone of said second section through said bypass passageway and the pressure thereof causes said check valve to open, and c. axial open position, said discharge port is open and said shoulder engages said check valve, opening the same; 45* rotation in either direction, said check valve remaining closed and said discharge valve remaining opeN, a leg passageway of said inlet set registers with said inlet port and the other leg passageway registers with one of said operating ports, and one of said discharge passageways registers with the other of said operating ports.

Claim 8

The valve of claim 5 wherein said bypass passageway forms a third member of said discharge set and is disposed on the periphery of said spool at a radial angle that bisects the outside angle between the other two passageways of said discharge set, said bypass passageway registering with said inlet port when said spool is in said 0* position.

Claim 9

In a rotary spool valve having a flow directing rotary spool mating with and rotatable in a cylindrical valve chamber, said valve chamber having in the cylindrical wall thereof an inlet port and a first and a second operating port radially disposed 45* on either side of said inlet port, and said spool having opposed first and second directing ports facing said cyindrical wall and connected by a common passageway, said first directing port when said spool is in a first operating position registering with said inlet port while said second directing port registers with said second operating port and said second directing port when said spool is rotated to a second operating position registering with said inlet port while said first directing port registers with said first operating port, the improvement comprising: a pressure balancing port in said spool facing said cylincrical wall and connecting with said common passageway, said pressure balancing port being centrally disposed on the line that bisects the outside angle between said directing ports when viewed in a cross section of said spool, and the surface area of said pressure balancing port contacting said cylindrical wall being so proportioned with respect to the combined similar surface area of said directing ports and the angular disposition thereof that the displacing forces on said spool by fluid confined by said directing and pressure balancing ports are balanced.

Claim 10

In a rotary spool valve having a flow directing rotary spool mating with and rotatable in a cylindrical valve chamber, said valve chamber having in the cylindrical wall thereof an inlet port and a first and a second operating port radially disposed 45* on either side of said inlet port, and said spool having opposed first and second directing ports facing said cyindrical wall and connected by a common passageway, said first directing port when said spool is in a first operating position registering with said inlet port while said second directing port registers with said second operating port and said second directing port when said spool is rotated to a second operating position registering with said inlet port while said first directing port registers with said first operating port, the improvement comprising: a pressure balancing port in said spool facing said cylincrical wall and connecting with said common passageway, said pressure balancing port being centrally disposed on the line that bisects the outside angle between said directing ports when viewed in a cross section of said spool, and the surface area of said pressure balancing port contacting said cylindrical wall being so proportioned with respect to the combined similar surface area of said directing ports and the angular disposition thereof that the displacing forces on said spool by fluid confined by said directing and pressure balancing ports are balanced.

Claim 11

The valve of claim 7 wherein a portion of each of said ports overlap a common plane perpendicular to the axis of rotation of said spool.

Claim 12

The valve of claim 7 wherein said common passageway is composed of three intersecting interior passageways in said spool, one each of which connects to one of said directing and pressure balancing ports.

Claim 13

The valve of claim 7 wherein said common passageway is a circumferential groove in the periphery of said spool.

Claim 14

The valve of claim 7 wherein said common passageway is a circumferential groove in said cylindrical valve chamber intersecting said inlet port.