US3522821A - Pilot actuated valve - Google Patents

Description

United States [56] References Cited UNlTED STATES PATENTS 2,638,108 5/1953 Williams etal l37/625.26X 2,896,665 7/1959 Lieser 137/5961 2,898,936 8/1959 Collins 137/625.63 2,918,906 12/1959 Becker 137/596 3,171,438 3/1965 Helsing.... 137/625.26 3,249,123 5/1966 Berg l37/625.26

Primary Examiner- Henry T. Klinksiek Att0rney-Cullen, Sloman and Cantor ABSTRACT: A valve comprises a deformable ball acting as a spool valve in a control chamber to alternately connect a distributor passage to either exhaust or line pressure, while precluding the possibility of a direct temporary connection between supply and exhaust. The ball also acts as a poppet valve while deforming into and against the supply inlet port. The position of the ball is controlled by a piston which is acted upon by line pressure from a second distribution passage.

Patented Aug. 4, 1970 7 M w/ 1. l lm nnul l hl t a iii}. 4 a 1 w 4 H L\ FIGZ INVENTOR JEROME B. KOMENDERA 3&2, fa, w

ATTORN EYS US. PATENT 3,522,821 PILOT ACTUATED VALVE BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view, mostly in section of the valve in its normal or first condition.

FIG. 2 is a view similar to FIG. 1, but showing the valve in its second condition following actuation of the solenoid.

FIG. 3 is a cross sectional view taken in the direction of arrows 3-3 of FIG. 1.

FIG. 4 is a schematic diagram of the control circuit for the valve of this invention.

DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. I of the drawings, the invention generally comprises a valve body to which is connected a solenoid housing 12 (only a portion of which is shown). Valve body 10 has a longitudinal bore 14 including a central control chamber 16. Three flow passages lead into control chamber 16: A first distribution port 18 leads to first distribution passage 20; a first exhaust port 22 leads to first exhaust passage 24; and inlet port 26 interconnects control chamber 16 with the upper segment of longitudinal bore 14, leading to valve supply passage 28. As can be seen from FIGS. 1 and 3, port 18 exits out of the paper in FIG. 1, while port 22 exits into the paper in FIG. 1.

The upper segment of longitudinal bore 14 also communicates with asecond distribution passage 30 via channel 32, which is selectively and alternatively exposed to either positive pressure or exhaust by the action ofthe solenoid assembly 12. The plunger 34 of solenoid 12 controls passage 36 of seat 38, whereby spring 40 normally maintains plunger 34 in the position of FIG. 1 to block passage 36 and to establish communication between channel 32 and a second exhaust passage 42 in solenoid housing 12 via plunger bore 44.

Actuation of the solenoid causes the plunger 34 to assume the position of FIG. 2, whereby passage 36 is unblocked, and plunger O-ring 46 enters and seals plunger bore 44 to block exhaust passage 42.

Second distribution passage 30 also communicates with the lower segment of longitudinal bore14 by means of control passage 48. This lower portion of bore 14 has a piston 50 provided with a sealing O-ring 52 mounted for vertical movement. Piston 50 functions to control the position of ball 54 in control chamber 16.-

Ball 54 is fabricated of a resilient deformable material such as Buna-N or Viton, and is so dimensioned relative to the diameter of control chamber 16 to block and seal from each other the portions of the chamber lying on opposite sides of the ball. The ball may in fact be slightly oversize, so that some deformation is necessary for it to fit within chamber 16. This deformation, coupled with further flattening which occurs under fluid pressure, assures the desired sealing action. The ball become ellipsoidal under such pressure, and seals along its major axis. Piston50 acts as a stop for the ball, thus increasing such flattening effect.

, From FIGS. l and 3 it is apparent-that the lower positions of piston 50 and ball 54 blocks flow between port 18 and 22, while permitting flow between ports 18 and 26. In the upper position of piston 50 and ball 54, shown in FIG. 2, flow between ports 18 and 26 is blocked, while flow is established between ports 18 and 22.

FIG. 4 merely illustrates the valve body 10 and solenoid unit 12 with the associated'controls for the solenoid comprising a 7 battery 56 or other source ofelectrical energy 12 and a switch 58.

OPERATION The unique valve of this invention may be used to control the flow of pneumatic or hydraulic medium to the two ends of a double-acting cylinder or to two single acting cylinders. For operative illustration, it will be assumed that first distribution passage 20 is to be a normally open or pressurized line while second distribution passage 30 is to be normally exhausted.

LII

As explained above, in the normal condition of the valve and solenoid, illustrated in FIGS. 1 and 3, passage 20 is pressurized via supply passage 28, inlet port 26, control chamber 16, and port 18. Ball 54 blocks flow between passage 20 and first exhaust passage 24. Simultaneously, second distribution passage 30 is exhausted via channel 32, plunger bore 44 and second exhaust passage 42, with plunger 34 blocking flow to passage 30 from supply passage 28. Similarly the lower portion of bore 14 is exhausted via control passage 48, channel 32, bore 44 and second exhaust passage 42, to place piston 50 and ball 54 in their lower positions under the influence of pressure from supply passage 28 acting on the top of ball 54.

When switch S8 actuates the solenoid, plunger 34 is driven upwardly against the bias of spring 40, opening passage 36 and blocking flow through plunger bore 44 to second exhaust passage 42. Pressure from supply passage 28 now flows via passage 36 and channel 32 to second distribution passage 30 and to the lower portion of longitudinal bore 14 via control passage 48. This drives piston 50 and ball 54 upwardly to the position of FIG. 2, forcing and deforming ball 54 against and partially into inlet port 26 to block flow from supply passage 28 to first distribution passage 20. Upward movement of ball 54 also establishes flow from first distribution passage 20 to first exhaust passage 24 via control chamber 16. Interruption of current to solenoid will re-establish the condition of FIGS. 1 and 3 under the action of spring 40.

Thus, the unique valve of this invention includes a deformable ball which acts as a closed-center spool valve to prevent blow-by between the inlet port 26, first distribution port 18, and first exhaust port 22. The elimination of blowby improves the efficiency and positiveness of operation, since loss of line pressure resulting from leakage between the supply line and exhaust often causes the fluid-operated cylinder to hang-up rather than move positively between positions. In the present valve, the supply and exhaust lines are never interconnected through the control chamber. Ball 54 also acts as a poppet valve with respect to inlet port 26, and its deformation in the condition of FIG. 2 assures a complete seal at that port when desired. The ability of ball 54 to deform has other advantages. First, it absorbs misalignments and makes dimensional tolerances less critical, thus reducing the cost of machining. Secondly, the resilience and deformability acts to absorb shock which would otherwise occur as the valve bottomed in its respective positions. This property also makes the valve virtually indestructible. Its light weight cuts the inertia of the mechanism.

While the ball has been described as fabricated entirely of a readily deformable material, it is to be understood that it could also be fabricated of a metal core coated with rubber or urethane or other suitable deformable surface.

This invention may be further developed within the scope of the following claims. Accordingly, the above specification is to be interpreted as illustrative of only a single operative embodiment of this invention, rather than in a strictly limited sense.

I claim:

1. A valve for controlling and distributing the flow of a pneumatic or hydraulic medium comprising:

a body containing a longitudinal bore having a supply passage communicating therewith and a generally cylindrical control chamber portion intermediate the ends of said bore;

said body further containing a first distribution passage and a first exhaust passage each communicating with said control chamber through respective longitudinally spaced ports in the side walls of said control chamber;

said supply passage communicating with said control chamber through an inlet port located in one end of said control chamber and interconnecting said control chamber with said longitudinal bore;

said body further containing a second distribution passage and a second exhaust passage, said second distribution passage selectively communicating with first controls means operatively connected to said body,

and in a first condition establishing communication with said second distribution passage;

whereby said piston will permit said ball to assume its first position when said second distribution passage is connected to said second exhaust passage, and said piston between said second distribution passage and said 5 will cause said ball to assume its second position when second exhaust passage and blocking communication said second distribution passage is connected to said between said second distribution passage and said supply passage. supply passage, and in a second condition establishing 4. A valve comprising; communication between said supply passage and said a body containing a longitudinal bore having a first second distribution passage byasaid longitudinal bore; passage communicating therewith and a generally second control means operatively connected to said body cylindrical control chamber portion intermediate the comprising a resilient deformable ball slidably mounted ends of said bore; for reciprocal movement within said control chamber, said body further containing second and third passages the diameter of said ball being so dimensioned relative each communicating with said control chamber to the bore of the said control chamber as to continuthrough respective first and second longitudinally ously block any flow of the controlled medium past said spaced ports in the side walls of said control chamber; ball between opposite ends of said control chamber as said first passage communicating with said control separated by said ball; chamber through an inlet port located in one end of said second control means further comprising actuating said control chamber interconnecting said control means for selectively and alternatively causing said ball Chamber and longitudinal bore; to move between a first position between said longituc ntrol means operatively connected to said body comdinally spaced ports of said first distribution passage prising a resilient deformable ball slidably mounted for and said first exhaust passage to blo k omm ni tion reciprocal movement within said control chamber, the therebetween while permitting communication diameter of said ball being so dimensioned relative to between said f rst di tribution a age and id supply the bore of said control chamber as to continuously passage via said inlet port, and a second o ition block any flow of the controlled medium past said ball wherein said ball is deformed against said inlet port end between opposite n f i Control Chamber as of said control chamber to block said inlet port while separated y Said ball; permitting communication between said first distribu- Said mm m n f r h r mprising actuating means tion passage a d aid exhau t a age via id o t l for selectively and alternatively causing said ball to chamber. move between a first position between said first and 2. The valve of Claim 1 wherein the normal condition of Second longitudinally spaced p r to blOCk Communisaid valve is in the said first condition of each of said first and Cfllion thfirfibetween hil permitting mmuni li n second control means between said first passage and said second passage via 3. The valve ofClaim 1 wherein the second end of said lonsaid inlet a a e q Position said ball gitudinal bore adjoining and communicating with said control deformed agamst mlet P0rt f of control chamber has a piston reciprocally mounted therein, one end m to block Smd POrt whle perm'ttmg of said piston adapted to abut said ball and the opposite end of g Second Passage and Sam th'rd said piston being exposed to a control passage in said housing Passage Control Chamber and interconnecting said second end of said longitudinal bore 40

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