# Patent

## Title
Air cushion grip with a cubic supporting structure and shock-absorbing

## Abstract

This is a continuation-in-part of copening application Ser. No. 536,219 filed Jun. 11, 1990, now U.S. Pat. No. 5,105,504, which is a continuation-in-part of application Ser. No. 335,761 filed Apr. 10, 1989 now abandoned, which is a continuation-in-part of application Ser. No. 164,131 filed Mar. 4, 1988 now U.S. Pat. No. 4,933,017 dated Jun. 12, 1990, which is a continuation-in-part of application Ser. No. 90,756 filed Aug. 28, 1987 now abandoned.

## Background
The present invention is directed to an apparatus and method for opening slow and clogged drains in commercial, industrial and household applications and for purging any type of radiator cooled engines such as cars, trucks, etc., and cooling system for marine inboard and outboard motors.

It is a common problem that drains of various kinds such as household plumbing drains including bathtubs, showers, and so forth, periodically become clogged and need to be opened to restore normal usage. Typical methods for cleaning drains call for the use of chemicals including caustics and acids which are highly detrimental to plumbing systems and plumbing fixtures. Chemical treatments tend to destroy metal fittings while caustics attack ABS pipes, and acids attack porcelain. These chemicals are dangerous to handle and are pollutants. In other techniques, high pressure drain opening systems tend to rupture plumbing joints and snakes tend to damage the finish of plumbing fittings and fixtures. Accordingly, there is need for a safe, nondestructive, nonpolluting way of dealing with clogged plumbing drains.

Motor vehicle radiators over a period of time accumulate rust scale and other deposits which impede cooling efficiency and require periodic flushing to remove accumulated materials and to restore the radiator to full heat exchange efficiency. Typically, high pressure devices or acids are used for cleaning automobile radiators and are detrimental to the structural integrity of the radiator.

Marine inboard and outboard motors ordinarily have cooling systems using ambient water and tend to become coated with foreign materials carried along in the cooling water. It is desirable periodically to flush the cooling systems to remove such materials which substantially interfere with heat transfer of the cooling system and also when winterizing an engine.

When winterizing swimming pools, the filter system is secured and it is desirable to purge the filter lines of water and debris which remain in the lines.

There is a need for an apparatus and method which can quickly and effectively deal with clogged drains and flushing radiator and cooling systems and aid in cleaning or winterizing swimming pools.

The present invention provides a method and apparatus for conveniently and effectively opening drains in plumbing systems which is applicable to other opening/flushing operations such as cleaning motor vehicle radiators and marine engine cooling systems. According to the invention, a series of pressure pulses both positive and negative are applied in rapid succession effectively to move and clear away debris blocking drains or to aid in purging and flushing cooling systems.

In one form of the invention the drain opener includes an ordinary household wet/dry vacuum cleaner fitted with a pressure reversing header for quickly applying a repetition of negative and positive pressure pulses to the plugged drain. The header includes a manually operable valve member which when manipulated causes the wet/dry vacuum cleaner to apply alternate pressure and vacuum pulses to the drain in rapid succession effectively to clear the drain. In a modification of the invention, pressurized water and/or detergent cleaners can aid in drain opening.

In another form of the invention, the drain opener is suitable for use with household canister-type dry vacuum or wet/dry vacuum cleaners having a vacuum port and an exhaust port. The drain opener includes a wet canister fitted with a pressure reversing header connected to a dry vacuum cleaner by suitable hose connections. In this form of the invention the household vacuum cleaner whether dry or wet/dry are used for supplying pressure and vacuum pulses while the wet canister serves as receptacle for effluent form clogged drains.

It is an object of the invention to provide a drain opener and method of operation for rapidly cleaning clogged drains, motor vehicle radiators, marine engine cooling systems and the like, and purging filter system lines when winterizing or cleaning swimming pools.

Another object of the invention is to provide a fitting for a typical wet/dry vacuum cleaner which effectively applies alternating pulses to open drains.

A further object of the invention is to provide differential pressure pulses of a low magnitude which will not overpressure and damage household plumbing fittings or engine cooling systems.

Another object of the invention is to provide a drain opener suitable for use with canister-type dry and wet/dry vacuum cleaners in which the effluent form a slow or clogged drain is collected in a separate receptacle.

A further object of the invention is to provide a drain opener which is safe to use, does not damage plumbing fittings and fixtures, and does not result in chemical pollution of plumbing systems, septic systems, underground sewers, and so forth.

Another object of the invention is to provide a valve to alert the operator when effluent fills the receptacle.

A further object of the invention is to provide fittings for applying the method and apparatus to specific drains.

Other and further objects of the invention will become apparent on an understanding of the following detailed description or will become apparent to one skilled in the art upon employment of the invention in practice.

FIG. 1 is a schematic view of the apparatus for opening drains according to the present invention.

FIG. 2 is a perspective view of the pressure/vacuum control manifold according to the invention.

FIG. 3 is a section taken along line 3--3 of FIG. 2 to illustrate the interior of the control manifold.

FIG. 4 is a schematic view of modification of the invention in which a water feed is applied together with positive pressure pulses to a drain.

FIG. 5 is a schematic view of a modified control manifold according to the invention.

FIG. 6 is an elevational view in section of a further modification of the present invention.

FIG. 7 is a side elevational view of a blade valve and handle forming part of the modified embodiment of FIG. 6.

FIG. 8 is a side elevational view of a further modification of the invention showing the pressure/vacuum control manifold with a modified operating handle.

FIG. 9 is a top plan view of the manifold of FIG. 8.

FIG. 10 is a further modification of the invention illustrating a drain opener including a pressure/vacuum control manifold and receptacle for connection to a canister-type or wet/dry vacuum cleaner.

FIGS. 11a and 11b are sequential views of the pressure/vacuum control manifold in a pressure pulse mode (11a) and a wet vacuum mode (11b).

FIG. 12 is an elevational view of a float valve positioned within the receptacle of FIGS. 11a and 11b for closing entry to the manifold as the effluent level rises in the receptacle.

FIG. 13 is a side elevational view partly in section of a fitting for applying the method and apparatus to a sink drain.

FIG. 14 is a side elevational view partly in section of a fitting for applying the method and apparatus to a shower drain.

FIG. 15 is a side elevational view partly in section of a fitting for applying the method and apparatus to an automotive radiator.

FIG. 16 is a side elevational view partly in section of a fitting for applying the method and apparatus to a toilet.

FIG. 17 is a side elevational view partly in section of a fitting for applying the method and apparatus to a urinal.

FIG. 18 is a side elevational view partly in section of a fitting for applying the method and apparatus to a sink or tub drain.

FIGS. 19 and 20 are plan and section views respectively of a toilet cover.

FIG. 20 illustrates a detail of the cover of FIG. 19.

FIG. 21 is a side elevational view of a fitting for applying the apparatus within a pipe drain.

FIG. 22 is a side elevational view of a fitting for applying the apparatus to drain openings of various diameters.

Referring to the drawing, a preferred embodiment of the apparatus 10 for opening drains includes a suitable pressure/vacuum source, as for example, a wet/dry vacuum cleaner 12, a pressure/vacuum control manifold 14, and an operating hose 16 for opening a drain 18.

The vacuum cleaner includes an upright receptacle 20 having a motor driven fan 22 for drawing vacuum through an inlet port 24 to the interior 26 of the receptacle or canister 20 and for exhausting air from the canister through an outlet port 28. In this description these ports are referred to as vacuum port 24 and pressure port 28.

The wet and dry vacuum cleaner operates in the usual fashion to draw debris into the canister through vacuum port 24 while exhausting or evacuating the interior of the canister through pressure port 28. This basic manner of operation applies with respect to the present invention. The pressure/vacuum control manifold regulates the drain opening apparatus so as selectively to apply pressure or vacuum through operating hose 16 to drain 18.

The control manifold 14 includes an upright block shaped housing 30 formed of any suitable material such as rigid plastic or cast aluminum. The manifold includes interior vacuum 32 and pressure 34 ducts and exterior conical vacuum 36 and pressure 38 sleeves for connection to the vacuum 24 and pressure 28 ports of the vacuum cleaner. The vacuum and pressure ducts merge into an upwardly extending two-way pressure/vacuum duct 40 with an access port 42 located in the top surface 44 of the manifold. The front wall 46 has openings 48, 50 communicating with the interior vacuum and pressure ducts respectively for the purpose of drawing air into or exhausting air from the canister during operation as more fully developed below.

The control manifold further includes a control mechanism 52 for directing pressure/vacuum flow within the operating hose 16. The control mechanism includes a pivot shaft 54 extending horizontally through the manifold and lying along the top of a partition 56 separating the interior vacuum 32 and pressure ducts 34. The shaft is pivotally mounted between the front 46 and rear 50 walls of the manifold and includes a projection 60 extending a short distance from the front wall.

A blade-shaped valve or damper 62 is supported by and projects radially from the surface of pivot shaft 54 for directing flow through two-way duct 40 and operating house 16 by blocking either interior vacuum duct 32 or pressure duct 34. The contour of blade valve conforms to the interior wall surface of vacuum duct and pressure duct at their places of confluence with two-way duct in an air tight fit to avoid pressure loss during operation. The control mechanism further includes a movable cover 64 for selectively closing openings 48, 50 in front wall 46. The cover is connected to pivot shaft 54 by means of extension rod 66 for pivoting movement between the openings. A suitable knob 68 is fitted to the cover for ease of manipulating the cover. It is to be observed that blade valve 62 and extension rod 66 are coplanar so that when the blade valve covers the pressure duct 34, for example, the pressure opening 50 will be uncovered and vice-versa for vacuum duct 32 and vacuum opening 48.

In operation, the control mechanism is set in one position as for example, the solid line position of FIGS. 2 and 3 in which case exhaust air is expelled from the vacuum cleaner through the pressure duct 34 and pressure opening 50 while the external cover 64 closed vacuum opening 48 and opens vacuum duct 32 drawing air into the vacuum cleaner through hose 16. The position of valve 62 assures draw of partial vacuum through operational hose 16 and application of vacuum to the blocked drain. By reversing the position of the handle and control mechanism (to the dash line position of FIG. 3), pressure is now applied to the operating hose and drain. As shown in the dash line portion of FIG. 3, air is pushed into the operating hose through pressure duct 34 and into the drain while open vacuum port 48 provides for inflow of ambient air into the system.

By periodic manipulation of the control mechanism differential pressure pulsations are applied for effectively clearing the drain.

In like manner, the mechanism can be applied to other fittings such as automotive radiators, marine engines, and so on, for cleaning the fluid passages of such devices.

The invention is useful for cleaning or winterizing swimming pools particularly in purging water and any debris lodged in the filter recirculating and distribution lines.

If desired, auxiliary drain clearing aids such as detergent or pressurized water can be introduced through hose fitting 17 by means of an applicator 19 as shown in FIG. 1 and also in FIG. 4.

FIGS. 4 and 5 present a modification to the present invention in which water feed accompanies the positive pressure pulses of the system as an aid in opening drains and the like. Here a hand-held nozzle 70 is attached to hose fitting 17 and has a suitable fitting 72 for receiving a water supply hose. The nozzle includes a suitable valve 74 and is trigger actuated 76 for water supply. Additionally, the trigger forms part of an electric circuit 78 which also includes a control manifold solenoid 80 shown in FIG. 5. As the trigger is actuated water is applied to the drain and the solenoid-actuated movable cover 66 moved to the positive pressure mode. By releasing the trigger the water-feed is interrupted and a vacuum pulse applied to the drain. If desired, the nozzle may be used to feed detergents, degreasers, etc., to a drain.

A further modification of the invention is illustrated in FIGS. 6 and 7. The modified control manifold 90 includes an upright block-shaped housing 92 with an interior chamber 94 and a movable blade valve or damper 96 for directing pressure and vacuum pulses to a closed drain. The interior chamber includes a pressure chamber 98 through which pressurized air is applied to the drain or exhausted to atmosphere and a vacuum chamber 100 through which air is drawn from the drain or from atmosphere. The control manifold is generally rectangular in cross-section and includes rear 102, front 104 and side walls 106 of integral construction preferably of injection molded polypropylene. The side walls taper upwardly and inwardly at 102a from approximately two-thirds their vertical dimension terminating at a inlet/outlet sleeve 108. The upper portions of the front and rear walls are joined to and follow the contour of the tapered side wall portions 102a. The inner surface 110 of both tapered side walls just below inlet/outlet sleeve is beveled to from a sealing surface for engagement with the upper sealing surfaces 112 on both sides of the blade valve. An operating hose 113 fitted to the inlet/outlet sleeve communicates vacuum and pressure pulses to the drain.

The control manifold also includes an interior partition 114 comprising spaced partition walls 116 vertically oriented and extending between and attached to the front and rear walls. The interior partition is molded integral with the control manifold. The upper edges 118 of each partition wall are beveled to form a sealing surface for engaging the lower sealing surfaces 120 of the blade valve. Additionally, a stop shoulder 121 is located at the upper edge of each partition wall for limiting movement of the blade valve. The partition walls cooperate with the front wall and direct air into and out of a single inlet/outlet port 122 in the front wall.

The lower ends of the pressure and vacuum chambers have outlet 123 and inlet 125 ports, respectively, for connection to the corresponding ports of a vacuum cleaner substantially as shown in FIG. 1.

The generally rectangular blade valve shown in FIG. 7 comprises an imperforate valve plate 124 divided into major 124a and minor 124b parts along a pivot axis A--A defined by a hollow pivot hub 126. The pivot hub is generally cylindrical and is formed integral with the valve plate of suitable material such as polypropylene. The pivot hub receives a pivot shaft 128 which is assembled into the manifold at pivot openings 130, 132 located in front 104 and rear walls 102. A handle member 134 is fitted to the front end of the pivot shaft for manipulating the blade between vacuum and pressure positions.

As shown in FIG. 6, the control manifold has its blade valve closing the pressure chamber so that in operation the vacuum cleaner applies a vacuum pulse to the closed drain through inlet sleeve 108 and operating hose 113. Pressurized air from the vacuum cleaner enters the pressure chamber and is exhausted through outlet port 122. By reversing the valve position to the dash line position of FIG. 6, a pressure pulse is applied to the closed drain through outlet sleeve 108 and ambient air is drawn through the inlet port 122 into the vacuum chamber providing the source of pressurized air to the closed drain through operating hose 113.

The blade valve includes a spring member 136 (FIG. 7) fitted between the pivot shaft and front wall for resisting the tendency of the blade valve to shift (FIG. 6) under the influence of a pressure differential acting on the blade valve in the vacuum mode (solid line position of FIG. 6). Alternatively, a ball/detente arrangement between front wall 104 and the operating handle 134 may be used to provide positive positioning and holding of the blade valve in both pressure and vacuum positions.

FIGS. 8 and 9 illustrate a modification of the pressure/vacuum manifold of FIG. 6. This form of the manifold 90 includes housing 92, interior chamber 94 nd damper 96 for directing pressure and vacuum pulses to a closed drain. The damper 96 is manipulated between vacuum (full line) and pressure dash line) positions by means of operating handle 138. A pivot shaft 140 is mounted between front 142 and rear 144 walls and receives damper 96 in the manner of FIGS. 6 and 7. First and second levers 146, 148 are fitted to the ends of the pivot shaft extending along the front and rear walls and are joined at one end by a laterally extending gripping handle 150. The other ends of the levers extend away from the pivot shaft to provide balance to the operating handle. The outer surfaces of the front and rear walls are provided with abutments or stop members 152 which limit the movement of the operating handle without stressing the blade valve. The stop members 152 are conveniently molded integral to the front and rear walls. The operating handle is weighted for the purpose of counteracting the tendency of the blade valve 96 to move counterclockwise (FIG. 8) by reason of the pressure differential on the vacuum 96a face and pressure face 96b. The same pressure differential is sufficient to hold the operating handle in the pressure mode (dash lines FIG. 8). The handle itself provides a convenient and durable structure for rapidly switching the unit form pressure to vacuum modes. The other structural elements of FIGS. 8 and 9 have numerals corresponding to the same structural elements of FIG. 6.

FIG. 10 is a further modification of the invention illustrating a drain opener including a pressure/vacuum control manifold and receptacle for connection to a canister-type dry or wet/dry vacuum cleaner.

The drain opener includes a dedicated intermediate canister or receptacle 156 for receiving effluent from a plumbing drain 18, pressure/vacuum control manifold 90, and a canister-type dry or wet/dry vacuum cleaner 158. The arrangement provides for communication of pressure/vacuum pulses to plumbing drain 18 from pressure/vacuum source such as the canister-type vacuum cleaner 158 without requiring to the source vacuum cleaner to receive effluent from the plumbing drain. The effluent is received and retained by the intermediate canister 156. This modification includes a pressure/vacuum control manifold 90 as described above for FIGS. 8 and 9 as reflected by corresponding reference numerals of FIG. 10. As described above, the pressure/vacuum manifold 90 directs pressure or vacuum pulses through hose 113 to plugged plumbing drain 18.

The intermediate canister includes a bucket 160 of suitable capacity, e.g., five gallons, and tightly fitting top cover 162 held in place by several snap fittings 164. The top cover includes fittings defining a vacuum line 166 and a pressure line 168.

The vacuum line 166 includes a circular port 166a in the top surface of the cover and an upwardly directed elbow fitting 166b for connection to the vacuum port 158 of vacuum cleaner through a suitable hose 168. Both circular port 166a vacuum elbow 166b are open to the interior 170 of the bucket.

The pressure line 168 also includes a circular port 168a and an upwardly directed elbow 168b similar to the vacuum line fittings, however, the pressure line further includes a conduit connection 168c directly between pressure elbow and pressure port so that pressure pulses are sent from pressure source 158p through hose 172, pressure line 168, manifold 90 to plumbing drain via hose 113. In other words, the interior of the bucket is not subjected to pressure pulses.

In operating the embodiment of FIG. 10, the operating handle 150 is set in vacuum mode (solid lines) and a vacuum pulse drawn on clogged drain by vacuum source 158v. The bucket interior 170 is subject to vacuum conditions developed by the vacuum source. Effluent drawn from the drain in this operating mode is trapped in the bucket. By merely reversing the operating handle to pressure mode (dash lines) a pressure pulse is directed from pressure source through pressure line, manifold, hose 113, to drain. When the drain is clear, effluent in canister can be disposed of by removing the top cover.

If desired a liner 171 (FIG. 10) can be used for collection and disposal of effluent received by the container 160 (FIG. 10) or 20 (FIG. 1). Preferably the liner is of heavy gauge sheet material or of rigid material to maintain its shape in the vacuum mode.

FIGS. 11a and 11b illustrate a further modification of the invention. In this form of the invention the pressure/vacuum manifold 180 is arranged in horizontal orientation within an outer housing 182 of the drain opening device. A motor driven fan 184 within the housing provides pressure P and vacuum V sources with suitable connections 186, 188 to the manifold. The housing includes a base plate 190 and external cover 192 and is mounted on a receptacle 194 for receiving effluent from a closed drain and with a liner 171. A control damper 196 is mounted within the manifold on a pivot shaft 198 dividing interior chamber 200 into pressure 202 and vacuum 204 chambers. Preferably, the damper and its pivot shaft are integral and molded of suitable plastic. A U shaped handle 206 is fitted to opposite ends of the pivot shaft for manipulating the damper. A knob 208 attached to the handle through slot 210 provides for gripping and manipulating the damper. In operation, the damper normally assumes the position shown in FIG. 11a, i.e., the pressure mode where the incoming pressurized air opens the damper to direct pressure through the inlet/outlet port 212 to drain. As in the case with the embodiment of FIGS. 1-10, the damper is shifted from vacuum to pressure mode to provide sequential vacuum and pressure pulses to a drain. As shown in FIG. 11b, the operating handle may be restrained in the vacuum mode by a ring 214 fixed to the housing adjacent the slot 210. The restraining ring 214 is pivotally mounted to a base member 216 fixed to the housing. The ring slips over the knob and holds the damper in the vacuum position against the force of pressurized air which is direct through exhaust port 218 to atmosphere. In this position, the drain opening device can now be used as for wet vacuum operations with waste collected in the lined receptacle 194 through the two way duct 220 and vacuum chamber 200.

FIG. 11b further illustrates a force cup 222 particularly adapted for use with the present invention. The force cup includes a hemispheric upper portion 224 which is truncated to define an opening 226 for communicating with two-way duct 220. The edge of the force cup around opening 226 is flanged 228 for ease in connection with the two way duct. The opposite end 230 of the hemispheric portion includes an integral hollow neck wall portion 232 of gradually reduced diameter as the neck wall converges to an open end 234. The force cup is molded integral of rubber or a suitable rubber substituted with sufficient resiliency to conform to a variety drain contours and wall sufficient strength to withstand vacuum within as the drain opening device is used in vacuum mode particularly the wet vacuum mode of FIG. 11b.

In operating the drain opening apparatus with a receptacle liner, it is desirable for the liner to maintain its shape within the receptacle and not to interfere with the vacuum draw from the receptacle. As shown in FIG. 11a, the liner is provided with a pleated sidewall 171a for maintaining side wall rigidity for resisting side wall collapse during operation. Additionally, linear bottom wall 171b is fitted with double coated tape strips 171c for securing the liner to the receptacle bottom wall 194a. As a further measure in maintaining liner shape, manifold connection 188 extends well into the interior of receptacle 194 directing air flow therefrom toward the liner bottom wall 171b.

Manifold connection 188 preferably extends at least half the depth of receptacle and its length may be selected by user or manufacturer for the purpose of determining the volume of effluent received by the receptacle. When the effluent level rises to cover the lower open end 189 of connection 188 the air flow characteristics of the apparatus are changed and a change of motor pitch will alert the operator that the volume limits of the receptacle have been reached and the receptacle is to be emptied. This safety arrangement assures that no effluent will flow into the fan 184 through vacuum intake connection 186.

A modified safety arrangement 240 is shown in FIG. 12 for positively closing a manifold connection 186 for assuring that no effluent will flow into fan 184 (FIG. 11a). The safety arrangement includes a float valve 242 which closes manifold connection preferably the pressure connection 186 when effluent in the receptacle rises from below level A--A to level B--B. As shown, the receptacle cover or base plate 190 is open at 244 to accommodate manifold connection 186 which extends a short distance into the receptacle interior 170.

The safety valve assembly 240 comprises an open cagelike structure including upper 248 and lower 250 rings interconnected by a plurality of tubular posts 252. There are preferably four posts equally spaced above the perimeters of the upper and lower rings, with just two posts being illustrated in FIG. 12. The rings are fabricated of suitable inert material such as rigid plastic. The upper ring has a central opening 254 by which it is fitted onto the depending portion 256 of the manifold 186 connection and retained by a suitable fastener 258. The upper end 260 of each post is secured by suitable means not shown to the upper ring. The lower ring is fitted to the lower end 262 of each post and held there by suitable fasteners 264. The lower ring has a central opening 266 to accommodate the body of a float 268 forming part of the float valve assembly. The float valve 242 is also in the form of a ring or disc 270 with a central opening 272 slightly greater in size (diameter) than the lower end 256 of the manifold connection 186. The outer perimeter of the float ring includes a plurality of peripherally located openings 274 which permit sliding or floating movement of the valve upward and downward of the supporting and guiding posts 252. The floating disc 270 is provided at its underside with a float 268 of suitable buoyant material and of sufficient volume for floating upwardly on the effluent surface as it rises from below level A--A to level B--B shown in FIG. 12. When the float valve 242 reaches the upper limit of its excursionary range the upper surface 278 of the buoyant block exposed through ring opening 272 now closes the lower end 256 of the manifold connection barring entry of effluent. As this occurs, the normal sound of the operating motor 184 (FIG. 11a) will change pitch alerting the operator that the receptacle is filled and must be emptied.

It is also desirable to provide a suitable mesh screen 280 encircling the float valve assembly to assure that the buoyancy of the float valve is not altered by accumulation thereon of debris floating in the effluent.

The present invention further provides a set of fittings 290 for applying the drain opening apparatus to drains including sink drains (FIG. 13), shower stall drains (FIG. 14), and to automotive or marine radiators (FIG. 15). In each case the fittings include an adapter in the from of a truncated cone 292 having a central bore 294 for communicating vacuum and pressure pulses (indicated by arrows v and p) to a drain. The upper surface 296 of each adapter is greater in diameter than the lower surface 298 with an intervening outer conical surface 300 and is thereby enabled to seal drain openings of various sizes typically 1 to 3 inches. The upper surface of each adapter is recessed at 302 to accommodate the end of inlet/outlet duct 220.

The fitting 290 (FIG. 14) for shower drains further includes downwardly extending extension tubes 304 for applying pressure and vacuum pulses directly to material (M) blocking the drain which normally occupies the gooseneck section of the drain. The extension tubes are supported from the adapter shoulder or recess 302 and extend through the central bore. The tubes may come in various lengths and be joined as desired at 306 to reach drain blockages.

The fitting 290 of FIG. 15 includes a closure cap 308 affixed to the adapter at its conical surface 300 to provide for positive securement to a radiator filling opening 310. This featyre is particularly useful in dealing with hot or steaming radiators.

FIG. 16 illustrates a fitting 320 for use with toilets which in preferred form includes a generally spherical or bulbous plastic or rubber body 322 having an interior passage 324 for applying pressure and vacuum pulses to a toilet drain. The fitting includes an inlet tube 326 which may be formed integral with the body or provided as an insert. The tube provides an extension of the interior passage 324 and serves as a point of attachment to an inlet/outlet duct. This construction provides a body having greatest wall thickness at its midsection 328 to resist collapse or deflection when pressure/vacuum pulses are applied to the interior passage. The body is provided with an integral sealing member 330 for sealing the fitting in a toilet discharge line in order to assure that there is no leakage of pressure/vacuum pulses during operation. The sealing member includes a disc portion 332 projecting radially from the body midsection terminating in a downwardly directed skirt portion 334. In use, the lower portion 336 of the fitting projects into a toilet discharge opening and the sealing member especially the skirt engages the bowl surface around the opening providing the desired seal.

FIG. 17 illustrates a fitting for a urinal substantially similar to the fitting of FIG. 16 as indicated by common reference numerals. The urinal fitting of FIG. 17 omits the lower body portion so that the under surface 338 of the sealing disc is the end face of the fitting. The fitting is applied over the drain grille of a urinal with the sealing member surrounding the grille in engagement the urinal surface.

FIG. 18 illustrates a fitting 340 for use with sink, tub, or shower drains and comprises a hollow cone 342 of substantially constant wall thickness 344. In a preferred form, the cone has an inlet end 346 of say 3.5 inches and tapers to an outlet 348 of 0.625 (five-eighths) inches. The body of the cone may be marked at intervals of one, two, and three inches along its length so the user may lop off and discard the lower part of the cone enabling the remaining upper portion to fit a particular drain inlet size. The fitting is provided with an angled connector 350 for access to drains such as sink drains where a water tap or other plumbing installation interferes with vertical access of the fitting to the drain.

FIGS. 19 and 20 illustrate a plastic cover sheet 352 for covering a toilet bowl when using the drain opening apparatus. The cover protects the operator from splashback from the toilet when pressure pulses are applied to a tightly blocked drain. The cover is generally oval shaped, fabricated of transparent plastic sheet material and has a peripheral depending skirt 354 for securing the cover over the top of a bowl 356. The cover has a central opening 358 for accommodating a fitting and inlet/outlet duct such as shown in FIG. 16. The cover is split radially along parting lines 360, 362 from the central opening to its outer edge in order to provide a snug fit of the cover to the bowl by overlapping cover sections along the split. The periphery of the skirt is provided with a suitable fastener 364 such as Velcro or the like.

FIG. 21 illustrates an extension tube 366 for insertion into a drain for applying pressure/vacuum pulses and, if desired, a water spray W and a detergent spray D directly to a blockage for disturbing, diluting and dissolving the blockage for easier removal by the pressure/vacuum pulses. The extension tube includes an imperforate wall 368 with flexible positioning guides 370 for centering the tube within the drain. There are preferably three guides equally spaced about the circumference of the tube. A truncated conical plug 372 fitted to the top end of the tube positions the tube int eh drain and forms an air tight seal at the drain opening. Supply lines 374, 376 for applying water and detergent to the drain from external sources form part of the tube.

FIG. 22 illustrates a drain fitting 378 for application to a variety of drain diameters. The fitting is a truncated conical hollow structure tapering from say 5 inches at top to 2 inches at bottom and suitable for application to drains within this range. An adapter collar 380 in the form of a truncated cone with an inner taper corresponding to the outer taper of the base fitting enlarges the effective diameter of the base fitting for use in larger drain sizes over 5 inches for example.

The present invention has been described with particular reference to utilizing a household wet/dry vacuum cleaner in usual commercial form. It is within the purview of the present invention to provide apparatus for opening drains specifically built for the purpose as would be used for commercial or industrial applications in which the pressure/vacuum source together with the control mechanism are dedicated to drain opening applications and are of unitary construction. In such embodiment of the invention, a drive motor of greater horsepower is used to achieve higher levels of pressure/vacuum than are available with wet/dry vacuum cleaners and which are appropriate and required for clearing drains in commercial and industrial applications. Similarly, the present invention contemplates embodiments of the invention specifically designed for use in purging motor vehicle radiators, the cooling systems of marine engines, and so forth where pressure/vacuum levels are tailored specifically for these applications.

## Claims

1. An apparatus for opening drains comprising an operating hose, a pressure source and a vacuum source, a control manifold having an interior chamber, a valve member and partition means located in the interior chamber and cooperating to divide the interior chamber into a pressure chamber and a vacuum chamber, means for connecting the pressure chamber to the pressure source, means for connecting the vacuum chamber to the vacuum source, the control manifold having an inlet/outlet port for connecting the interior chamber to one end of the operating hose and therethrough to a plugged drain, means for portion the interior chamber to atmosphere, the valve member having a first position in which the pressure source and pressure chamber are connected to the drain and in which the vacuum chamber is ported to atmosphere, the valve having a second position in which the vacuum source and the vacuum chamber are connected to the drain and in which the pressure chamber is ported to atmosphere, and means for moving the valve member between the first and second positions rapidly to apply pressure pulses and vacuum pulses through the inlet/outlet port and through the operating hose to the drain for dislodging and removing the drain blockage, a receptacle communicating with the drain through the vacuum chamber for receiving effluent of the drain when the drain is connected to the vacuum source, the manifold having an open end communicating with the interior of the manifold for directing effluent into the receptacle, and a toilet fitting affixed to the other end of the operating hose, the fitting having a bulbous body with a generally cylindrical passage therethrough such that body wall thickness is greatest at the body midsection, and the fitting further having a sealing member encompassing its midsection in a plane generally normal to the central passage, and the sealing member comprising a annular disc affixed at its inner periphery to the body midsection and a skirt depending from the outer periphery of the disc.

2. An apparatus for opening drains comprising an operating hose, a pressure source and a vacuum source, a control manifold having an interior chamber, a valve member and partition means located in the interior chamber and cooperating to divide the interior chamber into a pressure chamber and a vacuum chamber, means for connecting the pressure chamber to the pressure source, means for connecting the vacuum chamber to the vacuum source, the control manifold having an inlet/outlet port for connecting the interior chamber to one end of the operating hose and therethrough to a plugged drain, means for portion the interior chamber to atmosphere, the valve member having a first position in which the pressure source and pressure chamber are connected to the drain and in which the vacuum chamber is ported to atmosphere, the valve having a second position in which the vacuum source and the vacuum chamber are connected to the drain and in which the pressure chamber is ported to atmosphere, and means for moving the valve member between the first and second positions rapidly to apply pressure pulses and vacuum pulses through the inlet/outlet port and through the operating hose to the drain for dislodging and removing the drain blockage, a receptacle communicating with the drain through the vacuum chamber for receiving effluent of the drain when the drain is connected to the vacuum source, the manifold having an open end communicating with the interior of the manifold for directing effluent into the receptacle, and a urinal fitting affixed to the other end of the operating hose, the fitting have a hemispheric body with a generally cylindrical passage therethrough such that body wall thickness is greatest at the body end face, and the fitting further having a sealing member encompassing the end face in a plane generally normal to the central passage, and the sealing member comprising an annular disc affixed at its inner periphery to the body adjacent the end face and a skirt depending from the outer periphery of the disc.

3. An apparatus for opening drains comprising an operating hose, a pressure source and a vacuum source, a control manifold having an interior chamber, a valve member and partition means located in the interior chamber and cooperating to divide the interior chamber into a pressure chamber and a vacuum chamber, means for connecting the pressure chamber to the pressure source, means for connecting the vacuum chamber to the vacuum source, the control manifold having an inlet/outlet port for connecting the interior chamber to one end of the operating hose and therethrough to a plugged drain, means for portion the interior chamber to atmosphere, the valve member having a first position in which the pressure source and pressure chamber are connected to the drain and in which the vacuum chamber is ported to atmosphere, the valve having a second position in which the vacuum source and the vacuum chamber are connected to the drain and in which the pressure chamber is ported to atmosphere, and means for moving the valve member between the first and second positions rapidly to apply pressure pulses and vacuum pulses through the inlet/outlet port and through the operating hose to the drain for dislodging and removing the drain blockage, a receptacle communicating with the drain through the vacuum chamber for receiving effluent of the drain when the drain is connected to the vacuum source, the manifold having an open end communicating with the interior of the manifold for directing effluent into the receptacle, and a drain fitting affixed to the other end of the operating hose, the fitting having a conical body with a generally conical passage therethrough such that body wall thickness is substantially the same the full length of the fitting, and the fitting further having markings on its outer surface corresponding to various drain sizes so that the operator may cut the fitting to size corresponding to a particular drain.

4. An apparatus for opening drains comprising an operating hose, a pressure source and a vacuum source, a control manifold having an interior chamber, a valve member and partition means located in the interior chamber and cooperating to divide the interior chamber into a pressure chamber and a vacuum chamber, means for connecting the pressure chamber to the pressure source, means for connecting the vacuum chamber to the vacuum source, the control manifold having an inlet/outlet port for connecting the interior chamber to one end of the operating hose and therethrough to a plugged drain, means for portion the interior chamber to atmosphere, the valve member having a first position in which the pressure source and pressure chamber are connected to the drain and in which the vacuum chamber is ported to atmosphere, the valve having a second position in which the vacuum source and the vacuum chamber are connected to the drain and in which the pressure chamber is ported to atmosphere, and means for moving the valve member between the first and second positions rapidly to apply pressure pulses and vacuum pulses through the inlet/outlet port and through the operating hose to the drain for dislodging and removing the drain blockage, a receptacle communicating with the drain through the vacuum chamber for receiving effluent of the drain when the drain is connected to the vacuum source, the manifold having an open end communicating with the interior of the manifold for directing effluent into the receptacle, a toilet fitting affixed to the other end of the operating hose, and a toilet cover of plastic sheet material having a central opening for accommodating the operating hose and fitting, a peripheral skirt for securing the cover to a toilet, and a radial split in the cover from the central opening to its periphery so that the cover may be drawn tightly about the operating hose at the central opening and the rim of the toilet.

5. The apparatus as defined in claim 4 in which the cover is transparent.