US 3768777 A
The disclosure describes a reciprocating manual slide valve with coaxial port and dispensing orifice, in which the outlet pressure of the valve and thereby the pressure differential across the port with the valve in the open position is controlled by the discharge orifice having a flow area sufficiently less than the effective flow area of the valve port that their ratio is greater than 2 to 1 whereby the downstream pressure at the valve port is only slightly less than the upstream pressure for high volume potential flow to the upstream side of the spray nozzle orifice at a substantially constant pressure for constancy of spray application. In one embodiment the valve stem has opposing effective areas externally balanced to atmosphere, and has equal areas on opposite sides of the valve that are appreciably greater in area than the balanced areas when the valve is closed, to hold the valve alternatively in its open and closed positions by the pressure of the liquid it controls. The valve stem areas are alternately increased when the valve is moved in alternate directions and by this pressure is urged with a snap action from intermediate positions to its closed position for safety. In another embodiment, the valve elements are externally unbalanced so that the valve must be held open and there is a small pressure, about 4 oz. tending to close the valve due to the flow of liquid thereby. A third embodiment allows the selective use of two nozzles in conjunction with the invention.
Description (OCR text may contain errors)
Imited States Patent 1 Hechler, IV
[ 1 Oct. 30, 1973 LIQUID SPRAY DEVICE  Inventor: Valentine Hechler, IV, 26 Meadow View Rd., Northfield, Ill.
 Filed: Apr. 26, 1971  Appl. No.: 137,541
 U.S. Cl. 251/319, 251/330  Int. Cl. Fl6k H36  Field of Search 251/319, 282, 320, 251/330  References Cited UNITED STATES PATENTS 818,054 4/1906 Sears 251/320 1,861,916 6/1932 I-Iennebohle... 251/282 3,304,048 2/1967 Roberts 251/282 X FOREIGN PATENTS OR APPLICATIONS 33,886 4/1905 Switzerland 251/330 305,208 4/1955 Switzerland... 593,479 10/1947 Great Britain 251/282 Primary ExaminerArnold Rosenthal Att0rneyI-Iarbaugh & Thomas  ABSTRACT The disclosure describes a reciprocating manual slide ill valve with coaxial port and dispensing orifice, in which the outlet pressure of the valve and thereby the pressure differential across the port with the valve in the open position is controlled by the discharge orifice having a flow area sufficiently less than the effective flow area of the valve port that their ratio is greater than 2 to 1 whereby the downstream pressure at the valve port is only slightly less than the upstream pressure for high volume potential flow to the upstream side of the spray nozzle orifice at a substantially constant pressure for constancy of spray application. In one embodiment the valve stem has opposing effective areas externally balanced to atmosphere, and has equal areas on opposite sides of the valve that are appreciably greater in area than the balanced areas when the valve is closed, to hold the valve alternatively in its open and closed positions by the pressure of the liquid it controls. The valve stem areas are alternately increased when the valve is moved in alternate directions and by this pressure is urged with a snap action from intermediate positions to its closed position for safety. In another embodiment, the valve elements are externally unbalanced so that the valve must be held open and there is a small pressure, about 4 oz. tending to close the valve due to the flow of liquid thereby. A third embodiment allows the selective use of two nozzles in conjunction with the invention.
3 Claims, 8 Drawing Figures Patented Oct. 30, 1973 3,?@8,777
2 SheetsSheet 2 FIG. 7
\ 232' fi/Zoo "Ami a;
231 INVEN TOR.- 207 WJLE/VTl/VE HECHLER i 230' F I 6'. 8 v 204 Afforneys mourn SPRAY nnvrcs CROSS REFERENCES TO RELATED APPLICATION This application relates to application Ser. No. 625,086 filed Mar. 27, 1967 and 520,568 filed Jan. 14, 1966.
BACKGROUND OF THE INVENTION Heretofore the manual control of dispensing spray applications of mixtures under municipal water pressures has required a poppet type valve that is hand held open against either the water pressure or a closing spring, or both. Levers have been employed to reduce the manual strain but such a valve construction not only is sizable and cumbersome, but the spray from the valve body generally is limited to axial flow so that manipulation for special flow directions is almost impossible while continuing to hold the valve open. Other types of valves also have this latter difficulty and a conventional one involving turning a part of the valve assembly to reduce the manual effort in varying and stopping the flow, is slow and generally requires two hands to operate.
The heavy opening effort and constancy of orientation of holding and directing the valve not only fatigues the user but the spray also generally being conical rather than fan shaped, reduces the accuracy and care desired in spraying herbicides, pesticides and the like. In comparison with the present invention, other disadvantages and lack of advantages will be noted in the prior art.
SUMMARY OF THE INVENTION Not only are quickness and ease of valve operation that are greatly desired, provided by the present invention, but the operation is further coupled and benefitted in its action and response with a fan spray nozzle orifice for universal orientation of spray direction which also develops a back pressure on the valve port for a low pressure differential across the valve port. Within the limits of the municipal water pressure, the back pressure at the port outlet varies as the square of the relative flow ratio in the valve of this invention. Thereby, a high back pressure approaching the valve inlet pressure is present at the valve outlet and nozzle with a relative flow area between the valve and the nozzle orifice in excess of 2 to 1.
Thus, there is no substantial drop of pressure across the valve port for a reasonably wide range of nozzle sizes since the flow pressure applied to the nozzle will be reasonably close to the valve inlet pressure for operation of the valve in which a direct acting and light finger effort is all that is required to change the position of the valve quickly. The fingers and hand are then free at all other times to manipulate and direct the spray in any direction and orientation. A corollary advantage of the above is that these differential relationships vary very little with differences in municipal water pressures in various communities.
In accomplishing the concept of a light and universal control of a large volume spray applicator utilizing municipal water pressures for critical mixtures, the opposite push rod portions of the slide valve having an axially aligned port are exposed to atmosphere with sectional areas that are slightly less than the valve flow area when the valve is open. Thus, the valve movement from either closed or open position can be accomplished with a light manual effort.
In brief, with the valve closed, the upstream pressure balances out for the areas of the rods and leaves only the area differential of the flow area of the port thereover to urge closing. Thus, an area of the upstream rod can be provided relatively for any actuation lightness desired. When the valve is open against the flow, the rod areas also balance out, approximately, with little if any pressure drop at the valve port leaving only the area differential of the piston valve thereover to urge maintenance of open position. Thus, the area of the downstream valve rod is designed for any lightness desired for manually actuating the valve to close. A piston valve changing its effective area in excursion can also vary the lightness of touch control.
Furthermore, seals are provided which not only terminally cushion the valve in its movement, but also are engaged over an area larger than that of the slide valve rods. This also somewhat unbalances the rod areas favorably in a direction tending to hold the valve in either terminal position. This is of particular interest with the valve in its open position where hydraulic flow might otherwise tend to close it. In one embodiment a selected portion of this hydraulic flow pressure is used to urge the valve into a closed position and the valve can be held open with slight finger pressure.
The differential in pressures across the valve port depends upon its flow area compared with the spray nozzle orifice area. A valve flow area for a predetermined differential in pressures for a particular nozzle flow area can be computed and the valve port and nozzle orifice will perform accordingly throughout a range of municipal pressures, because the nozzle flow volume varies as the square root of the pressures. Flow variations consigned to the square root of the pressure changes are substantially minimized. Moreover, a range of smaller nozzle orifices can also be used with material change in the ease of the valve operation.
IN THE DRAWINGS FIG. I. is a diagrammatical view of the device embodying the invention used for lawn care;
FIGS. 2 and 3 are fragmentary perspective views of the nozzle demonstrating its adjustability in two of its positions;
FIG. 4 is an enlarged sectional view taken longitudinally of the valve body, connecting conduit and spray head with the valve in open position;
FIG. 5 is a view of the valve shown in FIG. 4 with the valve moved to a position just starting or just relinquishing its closed position;
FIG. 6 is a cross-sectional view similar to FIG. 4 of a modified form of the valve of this invention shown in closed position or just as it is being released from its closed position;
FIG. 7 is a view of the valve shown in FIG. 6 with the valve in open position.
FIG. 8 is a fragmentary cross-sectional view of a form of the valve of this invention modified to selectively operate two nozzles.
THE PREFERRED EMBODIMENT Referring to the drawings in further detail, the disclosure of said application Ser. No. 625,086 is incorporated herein by reference for a fuller detailed description of the structure shown in FIG. 1 in which a fluid flow proportioning device can be located at either end of a garden hose 12 that is supplied with water at municipal pressure from a valved water tap or sill cock 14, preferably through a short section of flexible hose 16. Liquid concentrate comprising water soluble area fertilizer is educted from the container 18 through a conduit 20 by the proportioning device 10 as more particularly described in Application Ser. No. 520,568 by the action of the water flowing through it and a valve control 22 is provided by which the concentrate can be selectively supplied or shut off. The concentrate can be either a fertilizer, or a herbicide, pesticide or other solutions with or without additives. The pressure drop across the proportioning device 10 is slight and with municipal pressures in various communities that can vary from 30 to 45 p.s.i. the ultimate spray pattern is very critically controlled by the action of the relative flow areas of the valve port and orifice provided in accordance with this invention at the outlet of the hose. A spray wand or applicator 26 with nozzle 30 is provided, as more particularly shown in FIGS. 2 and 3.
The nozzle 30 is adjustably positioned rotatively on the end of the short arm 32 of an L-shaped dispensing tube 34. The orifice 36 extends axially through the body 38 where it opens on a conventional compoundconvexly-curved distribution face 40 designed to provide a fan-like spray of uniform volume along the line of application. The base 42 of the body is reduced in diameter and has a cylindrical portion 44 fitting within a mating cylindrical surface at the end of the arm 32. The cylindrical portion is provided with an annular channel 46 receiving an O-ring seal 48 frictionally therein between the two elements. The end portion 42 of the base is provided with a machine thread 50 received in a corresponding threaded end portion 52 in the arm 32 to secure the nozzle in place, the threaded relationship providing for relative rotatable adjustment of the nozzle as frictionally held by the O-ring 48.
The finger controlled cut-off valve mentioned is indicated at 54 and comprises a body 56 (FIGS. 4 and 5) recessed at the outlet end, as at 58, to receive the other end of the tube 32 in sealed relationship. The inlet end of the valve body has an external flange 60 receiving a swivel nut 62 with an internal flange 64 engaging around the inside of the flange 60. An O-ring seal 66 is frictionally supported within the threaded portion 68 of the nut 62 which hold the nut in place on the body and seals the joint between the male end of the hose 12 (See FIG. 1) and the flanged end 60 of the body when secured together in dispensing relationship.
The valve body 54 can be of any desired length, but as compactly shown it has been cored in forming to have two radially spaced axially overlapping flow chambers 70 and 72 with a common wall 73 between them. The inlet chamber 70, communicating with hose 12, is shown as the upper one and the outlet chamber 72, communicating with the tube 32, is shown as the lower one. Each chamber preferably has parallel radially spaced planar upper and lower walls. The upper and lower walls of the inlet chamber 70 are indicated at 74 and '76 respectively.
A cross opening is bored by a form tool from one side of the body to the other perpendicular to the planar walls and the intermediate wall 73. The shape of the base is shown in which a cylindrical port 78 is provided through the common wall with a valve seat on the inlet chamber side of the wall 73, and cavities 80 and 82 are provided in the outer walls of the chambers receiving O-ring seals 84. One of the cavities comprises a shoulder 86 supporting the O-ring surrounding an opening 87 of reduced diameter open to the atmosphere. The other cavity 82 is formed by a collar or ring 88 received in a terminal enlargement 89 of the cross bore to hold the other O-ring in place.
A slide valve 90, defining a surface of revolution, is axially movable in the cross bore, the cylindrical character of the fit therebetween permitting the valve 90 full movement between and against the O ring seals 84. The valve member is a plastic formed member having push rod end portions 92 and 94 with a connecting enlarged portion 96 defining shoulder 98 and 100, respectively, and a radial and intermediate flange 102 bordering an annular groove 104 which receives a chevron type resilient gasket with its flange portion 106 directed towards the inlet chamber 70 and marginally terminating in a semi-feathered edge 108 of a diameter larger than the port '78. The upper wall of the groove 104 is tapered to accommodate the inward displacement of the feature edge when the valve is closed.
The cross-sectional areas of the push rod portions 92 and 94 at the O-rings 84 are substantially equal, and also the areas of the shoulders 98 and 100. When the valve is closed as shown in FIG. 5 the effective area exposed to atmosphere is the shoulder which is greater than the cross-sectional area of the push rod 92. The extra area of the shoulder holds the valve in open position, and since the flow area of the valve is more than twice the flow area of the orifice 36 (FIG. 4) there is very little pressure differential across the valve port to disturb this relationship. With this relationship the atmospheric pressure areas are opposing and substantially balanced except for the shoulder area. Accordingly, due to the differential shoulder area the closure of the valve is very easily accomplished by finger pressure.
When the valve is closed the rod areas effective for the upper chamber are equal and opposing with respect to inlet pressure and atmosphere, leaving a differential area related to the larger size of the port with respect to inlet pressure opposing the valve opening. This differential area can be varied by the relative size of the rod section 34 for the finger touch pressure desired. Nominal effort is involved in sliding the valve towards its open position until the gasket breaks from the port opening 78 whereupon inertial movement of finger pressure will break the contact and flow will begin.
However, since the break away of the gasket will quickly afford a flow rate opening which exceeds that of the nozzle orifice and the tube 32 is generally liquid solid, the pressure differential will quickly lessen and assume the relationship of an open valve thereby permitting light finger pressure to accomplish the opening of the valve for easy intermittent operation of the valve.
it will be further noted that, once open, a persons hand is free to direct the spray 110 from the nozzle in any direction by universal rotation of the tube 32 by hand about its axis and around the valve, while the nozzle can also be finger adjusted through 360 with only a momentary closing of the valve.
Assuming a pressure of 40 p.s.i. on the inlet side 70 of the valve 90, the ultimate flow rate is determined by the nozzle orifice 36 and this would vary as the square root of the upstream pressure. A differential of even several pounds across the large sized valve port would not vary the flow rate for all practical purposes. This relationship would follow with any size orifice once the municipal water pressure is known. Thus, uniform application is assured under normal circumstances.
Referring to FIGS. 6 and 7 another form of valve 120 is shown in juxtaposition to the nozzle 30 with which the valve would be connected by means of the wand 26. It is to be understood that the orifice 36 can be remote from the valve 120 or both the valve and nozzle can be part of a compact spray head, as desired.
The valve 120 has the inlet passage 122 and the outlet passage 124 formed within the body 126 in radially displaced relationship and overlapping so that the end wall 128 of the passage 122 extends a substantial distance beyond the end wall 138 of the outlet passage 124, similar to the arrangement shown in FIGS. 4 and 5. The bottom surface 140 of the passage 122 is essentially flat and coplanar with the bottom surface 142 of the outlet passage 124. The configurations of the remaining walls of the passages 122 and 124 are immaterial as long as they define equal or substantially equal cross-section areas. The outlet passage 124 communicates with the orifice 36 as through the wand 26.
A cross bore is provided in the valve body 126 extending through the top wall as at 144 through the intervening wall 146 as at the bore 148 and terminating in the blind bore 150 having the flat bottom wall 152 at the other side of the valve body 126. The smaller bore 154 extends through the wall 152 to the outside of the valve body. Within the bore 144 there is provided the internal flange 156 which receives the circular plug 158 in fluid tight relationship. The plug 158 is sufficiently resilient to be forced into a press fit within the flange 156. The plug 158 has the inner flat surface 160 enclosed by the bore 144 and functions as a stop member to be described.
The valve member 162 is carried in the coaxial cross bores 144, 148 and 154 and is provided with a head 164 having the flat upper surface 166 with the radial edge off-set wall 168 spaced therefrom defining the shank 170 of reduced diameter and also having the radial flange 172 spaced from the edge 168 defining an annular recess therebetween. The other end of the valve member 162 has the radial edge or off-set 174 defining the shaft 176 of reduced diameter which is slideably engaged within the bore 154. The outer end of the shaft portion 176 carries the finger knob 174 having the inner flat surface 180 at its hub.
The valve member 162 carries the chevron type resilient gasket 182 on the shank 170 within the annular space between the edge 168 and the radial flange 172. The gasket 182 has an inner circumferential converging feather-edged flange 184 which is sealed against the shank 170 by its resiliency and the outer circumferential diverging feather-edged flange 186 which is pressed against the wall of the bore 148 when the valve member 162 is in the closed position illustrated in FIG. 6 The bottom of the gasket 182 is flat and rests in sealed relationship against the adjacent side of the flange 172. The top feather edge of the outer flange 186 is spaced as at 188 from the edge 168 although the inner flange 184 can be long enough to seat both against the flange 172 and the edge 168. Thus the outer flange 182 forms a sealing surface.
The bore 150, the edge 174 and the shaft 176 form a circumferential enclosure for the second chevron shaped gasket 182 with its base seated upon the flat wall 152 and its inner flange 184 sealed against the shaft 176 in sliding relationship. The outer flange 186 is sealed against the bore 150. This lower gasket is stationary while the upper gasket moves with the valve member 162.
The valve member 162 is so dimensioned that in the closed position shown in FIG. 6 the inner flange 184 is pressed slightly against the edge 174 as a cushion and seal while the flange 186 of the other movable gasket is brought into compressed and sealed relationship within the bore 148 and at the same time the head 164 extends slightly within the bore 144, in guided reciprocable relationship. In this position the distance between the surfaces and 166 of the plug 158 and the head 164, respectively, and the distance between the face of the finger knob 178 and the outer surface 190 of the valve body are substantially equal. Flow through the passageways 126, 148 and 124 to the orifice 36 is closed and the fluid pressure in the passageway 122 working on the face 166 and on the gasket 182 through the clearance 188 holds the valve closed.
Slight finger pressure on the knob 178 moves the valve 162 to the open position shown in FIG. 7 wherein the gasket 182 has moved out of the bore 148 and liquid flow through the valve takes place in accordance with the arrows. In the open position the circumferential flow passage 192 has an effective area greater than twice that of the orifice 36.
Another embodiment of the invention is the spray head valve assembly 200 shown in FIG. 8 wherein the valve body 202 has a lower shank portion 204 which is brazed to, otherwise attached or made integral with the end of the spray wand 26, as shown in FIG. 1. Certain of the parts in the valve assembly 200 are identical as illustrated and also interchangeable or can be so constituted. In order to avoid any undue duplication of reference numbers these identical parts are described in pairs and, as will be apparent, the description of one such part will apply to the other. Also it will be apparent that certain of the parts can be formed of one piece instead of being formed of parts that are brazed or otherwise affixed, one to the other.
Thus, the valve body 202 has the longitudinal bore 206 through the lower shank portion 204 providing an inlet passage communicating with the source of fluids to be handled. The transverse or cross bore 207 is provided in the valve body 202 which intersects and is in communication with the inlet passage 206. The transverse bore 207 receives a pair of identical valve housing members 208 and 208 having an inner end illustrated at 210 which is brazed or otherwise affixed thereto and extending into the transverse bore 207 to the outer periphery of the inlet passage 206 and forming a unified T-shaped housing member constituting the valve body 202.
The valve housing members 208 are preferably identical. Thus, each is machined to form a pair of axially spaced inner radial flanges 212 defining therebetween the inner annular recess 214, the intermediate shank portion 218, the pair of outer axially spaced radial flanges 220 defining therebetween the outer annular recess 221, and, the outer externally threaded shank portion 224. Each valve housing 208 is inserted in the valve body 202 so that the innermost of the radial flanges 212 abuts the side of the valve body 202 and this juncture is a permanent seal. The inner annular recess 214 retains the O-ring seal 216.
The intermediate shank portion 218 may be of lesser diameter than the inner end portion 210 and is provided with the transverse bore 219 through the opposite walls which is preferably, but not necessarily, oriented essentially parallel to the inlet passage 206 in the valve body 202. The outer radial flanges 220 and the outer annular recess 221 therebetween are preferably of a lesser diameter than the inner radial flanges 212 and the inner annular recess 214, respectively. The outer annular recess 221 retains the O-ring seal 222.
The outer threaded shank portion 224 for each housing member may be of lesser diameter than the intermediate shank portion 218. Each of the valve housings 208 is provided with the longitudinal open ended bore 225 which has a substantially uniform diameter at the inner and outer ends and has the intermediate shank portion 218 where a bore section 227 is reamed out to a larger diameter than the rest of the bore 225 and has the opposite facing chamfered shoulders 228 at each end of the section. The combination of the longitudinal bore 225 and the inlet passage 206 forms a T-shaped passageway within the T-shaped valve body formed by the body 202 and the housing 208.
Two nozzle holders 230 and 230 are provided and can be formed from a blank similar in construction to the valve body 202. Thus, each nozzle holder is longitudinally bored through its shank portion to form the outlet passages 232 and have the larger diameter threaded sections 234 to accommodate the nozzles 30 only partially shown (see FIG. 4). The transverse bore 235 is provided through each of the nozzle holders 230, intersecting the outlet passages 232 and 232 and preferably having a diameter slightly greater than that of the pair of inner radial flanges 212. The transverse bore 235 in each nozzle holder has a reduced outer end 236 which preferably has a diameter slightly greater than that of the outer radial flanges 220. The transverse bores 235 and their reduced outer ends 236 are sealed by the rings 216 and 222, respectively. Thus the nozzle holders are rotatably attached to the valve housing members 208 and can be rotated 360 thereon, while abutting the valve body 202 in sealed relationship. The nuts 237 are attached to the threaded portions 224 of the valve housings 208 to hold the nozzle holders in the rotatable sealed relationship. In this manner, the nozzle holders 230 and the nozzles 30 have their bores in continuous communication through the bores 219 in any radial attitude about the housing members 208, as controlled by the slide valve body 238 now to be described.
The slide valve body 238 is axially movable in the longitudinal bore 225 of the aligned valve housing members on each side of the assembly 208. The slide valve body 238 is symmetrical and includes the push rod end portions 240 and 242 with the intermediate shank 2&4 defining a section of reduced diameter therebetween. An annular groove 246 is provided at the innermost ends of the shanks 240 and 242 to accommodate the pair of O-ring seals as indicated at 248 and 250.
When the push rod end portion 242 of the slide valve body 238 is pushed to the position shown in FIG. 8 within the aligned pair of housings 208 and the O-ring seal 248 on the other end portion 240 passes against the outer shoulder 228 of the section 227 and snaps into a compressed position as shown, to close and seal this end of the bore 225. Liquid from the wand is free to pass from the passage 206 into the bore 225 and the enlarged section 227 and out the passage 232 of the rotatable nozzle 230, as indicated by the arrows. At the same time, the O-ring 250 on the push rod portion 242 has passed against the inner shoulder 228 of the nozzle 230 and has sealed this end of the passageway or bore 225 and flow through the nozzle holder 230' is stopped. Conversely, when the position of the slide valve 238 is reversed by pushing the end portion 240 to the right, the relative positions of the O-ring seals 248 and 250 is also reversed bringing the seal 248 against the opposite end of the section 227 and into the bore 225 in snap-sealing relationship while simultaneously the seal 250 opens the passageway 225 at that end, and is pressed against the corresponding outer beveled shoulder 228' of the housing 208'. The nozzle holder 230 and its passageway 232 is then in open communication with the bore 206 while the nozzle 230 is closed. The reciprocation of the slide valve body to and from these positions is a positive snap action as the seals 248 and 250 simultaneously snap into their positions at the ends of their respective enlarged sections 227.
When necessary for the purpose'of changing nozzles for cleaning, the spray head valve assembly 200 can be taken apart. First the slide valve body 238 is pulled out of the bore 225 from either end and the nuts 237 are removed. The nozzle holders 230 can then be removed by sliding them off the valve stem 208. Assembly is accomplished by essentially the reverse process. The outermost of the O-ring seals 222 on the valve housing 208 and 208' have a smaller circumference than the inner O-ring seals 216, to avoid uneven wear on these seals due to assembly and disassembly and to allow the use of less force in installing and removing the nozzle holders 230 without sacrificing sealing.
If desired, the dimensions of this embodiment can be altered so that a third, intermediate position is provided for the slide valve body 238 wherein the O-ring 248 seals the bore 225 between the inlet passage 206 and the outlet passage 232 while the O-ring 250 seals the bore 225 between the inlet passage 206 and the outlet passage 232. This simultaneous sealing of the bore 225 around the inlet passage 206 creates a shut-off configuration for the valve without detracting from its function as hereinbefore disclosed.
What is claimed is:
l. A valve comprising:
a valve body having an inlet opening and an outlet opening;
an inlet chamber communicating with said inlet opening;
an outlet chamber communicating with said outlet opening;
a common wall between said inlet and outlet chambers;
a valve port in said common wall interconnecting said chambers and defining a valve seat exposed to said inlet chamber;
an opening to atmosphere in said valve body in the outer walls of each of said chambers, said openings being substantially coaxial with said seat of said valve port with at least one opening of lesser diameter than said valve port and having a planar surface thereabout defined by the wall of said inlet chamber and facing said valve port;
a slide valve body freely movable within and radially spaced from said valve port and having one of its ends extending in reciprocating sealed relationship through said one of said openings in said valve body; and
resilient sealing means carried by said slide valve body in said inlet chamber,
said resilient sealing means having a diverging flange portion flared against the path of flow of fluid through said valve terminating in a planar circular edge adapted to engage in sealing relationship against said planar surface about said one opening in said valve body in the open position and having a converging base portion of lesser diameter than said valve port and adapted to engage within and seal said valve seat in closed position.
2. A valve in accordance with claim 1 in which:
said common wall defines a second planar surface about and at an angle to said valve port and facing said planar surface about said one opening in substantially parallel relationship, and
the converging base portion of said resilient sealing means seats against the angle formed by said valve seat and said second planar surface in the closed position be held thereagainst by the pressure of fluid in said inlet chamber upon said diverging flange.
3. A valve in accordance with claim 1 in which:
said slide valve body has a circumferential groove thereabout with a radial flange nearest said valve seat;
said resilient sealing means has an inner bore through said converging base portion engaged by said groove and seated against said radial flange, and
the diverging flange of said resilient sealing means extends axially beyond said base portion and is radially spaced from said slide valve body to peripherally engage said planar surface and be held thereto by the flow of fluid in the open position of the valve.