Multi-container pressure washer and related product selecting valve

Information

  • Patent Grant
  • 6571805
  • Patent Number
    6,571,805
  • Date Filed
    Thursday, November 15, 2001
    22 years ago
  • Date Issued
    Tuesday, June 3, 2003
    21 years ago
Abstract
A pressure washer includes a chassis as well as a liquid pump, a pump-driving prime mover, plural chemical product containers and a product selecting valve, all supported by the chassis. Each of the containers is attached to a separate valve conduit extending to the valve and the valve is connected to a device conduit extending to the mixing device. A distributor is mounted for movement with respect to the valve body and has a channel for selectively connecting one of the valve conduits to the device conduit. The user may thereby use the pressure washer to dispense any one of plural solutions. A fresh water container facilitates “wash out” of the valve and device conduit before switching to another chemical product.
Description




FIELD OF THE INVENTION




This invention relates to fluid handling and, more particularly, to fluid handling systems, e.g., pressure washers, of the self-proportioning type.




BACKGROUND OF THE INVENTION




Pressure washers are widely known and widely used for such tasks as washing and wax-coating motor vehicles, preparing a building for painting, washing walkways and a host of similar tasks. Examples of pressure washers are disclosed in U.S. Pat. Nos. 5,409,032 (Berfield) and 5,718,255 (Gilpatrick et al.).




While pressure washers can be used with water alone (and are quite effective when so used), it is often desirable to mix a chemical product, e.g., a detergent, with water. The resulting solution is even more effective than plain water for certain purposes.




While certain types of pressure washers include a container for a chemical product, such pressure washers are disadvantageous for certain uses. Particularly, the user of the washer may, at different times, desire to use a detergent solution, an auto wax solution, a deck wash solution, as but a few examples. If the user desires to switch from one chemical product to another, it is preferred that the product container and all of the related tubing be first washed out with water. In other words, it is not a good idea (and may be self-defeating) to place an auto wax product into a container having detergent residue in it.




But insofar as is now known, there are no pressure washers which offer the product features and configuration which permit the user to quickly switch from one chemical product to another while yet avoiding diluting or impairing the quality of a product with residue from a previously-used product. And insofar as is now known, there is no selector valve suitable for use on such a pressure washer.




Another disadvantage of certain types of pressure washers arises from the mechanism used to control pump output pressure. A typical arrangement uses a pressure control knob which bypasses water in the pump. The knob is less than entirely convenient to use and its rotational position gives no indication of pressure or is only casually related thereto.




A multi-container pressure washer and related product selecting valve which addresses shortcomings of the prior art would be a distinct advance in the field of pressure washers.




OBJECT OF THE INVENTION




It is an object of the invention to provide a multi-container pressure washer addressing shortcomings of prior art pressure washers.




Another object of the invention is to provide a multi-container pressure washer which permits a user to quickly switch between different chemical products.




Another object of the invention is to provide a multi-container pressure washer having a product selecting valve facilitating quickly switching between different chemical products.




Yet another object of the invention is to provide a multi-container pressure washer which includes an easy-to-use pressure control. How these and other objects are accomplished will become apparent from the following descriptions and from the drawings.




SUMMARY OF THE INVENTION




Aspects of the invention involve a pressure washer of the type including a wheeled chassis as well as a liquid pump, a pump-driving prime mover, and a liquid container, all supported by the chassis. The pump has a water inlet port and is coupled to a mixing device such as a venturi-type eductor mixer.




In the improvement, the washer has first and second containers and a product selecting valve, also supported by the chassis. Each of the containers is attached to a separate, i.e., first and second input or valve conduit extending to the valve. The valve is connected to an output or device conduit extending to the mixing device. In a specific, highly preferred embodiment, the pressure washer has a total of four containers, three for chemical products and one for fresh “conduit rinse-out” water.




To set up the pressure washer for use, a relatively small quantity of a different chemical is poured into each of the three chemical product containers. Herein, each such undiluted chemical is referred to as a “concentrate.” A specified amount of water is then added to each such container (and to the chemical therein) and herein, each such moderately diluted substance is referred to as a “product.” The fourth container is filled only with water.




The multi-container, valve-equipped pressure washer permits the user to select (by valve manipulation) any one of several products, e.g., a detergent product, a car wash product, a deck wash product, an automobile wax product, or a multi-purpose cleaning product to be mixed with water from the pump. Herein, when a product is mixed with water from the pump, the resulting liquid delivered to the spray wand is referred to as a “solution.” The new pressure washer also permits the user to wash a product out of a conduit with fresh water from a separate water container before selecting another product to be mixed with the pumped water.




In more specific aspects of the invention, each of the containers includes a top fill neck and a neck cap or closure. The closures are “top-exposed,” thereby providing free access to the containers closures for container filling. (Top-exposed closures means closures which are accessible without moving or removing any other component of the pressure washer.) And in a specific embodiment, the containers are of the same size and shape and the closures are in registry with the same horizontal plane.




In another aspect of the invention, the pressure washer has a third container—and, most preferably, a fourth container. Each of the first, second and third containers includes a different chemical product. And the fourth container holds only water.




A highly preferred pressure washer has features which make the washer very easy to use. As examples, the washer has a control console with a product selector device and a pressure selector device mounted with respect to such console. In a specific embodiment, the product selector device is a rotary knob and the pressure selector device is a linearly-actuated lever controlling the throttle of the prime mover engine. On the console, the lever is identified by mnemonic symbols (e.g., L, M and H) and/or by graphic symbols related to pressure. (Since the pump rotates at engine speed, changing such engine speed will also change output pressure at the spray wand.)




In yet another aspect of the invention, the valve has a body with first, second, third and fourth inlet apertures formed in it. First, second, third and fourth conduits, respectively, are connected to such apertures. The valve body also has an outlet aperture having a device conduit attached to it and extending from the outlet aperture to the mixing device. A distributor is mounted for movement, e.g., sliding or rotary movement, with respect to the valve body and has a channel for selectively connecting one of the conduits to the device conduit.




When the distributor is set to connect a particular inlet conduit to the device conduit, it is preferred that the distributor be restrained from moving from the selected position. To that end, the valve includes a position retention mechanism coacting between the distributor and the valve body. In an exemplary embodiment, the position retention mechanism includes a plurality of shallow detent pockets and a pocket engagement member, e.g. a ball or the like, which is spring biased toward the pockets.




In more specific aspects of the invention, the distributor is mounted for rotational movement about an axis of rotation. The first, second, third and fourth inlet apertures extend along first, second, third and fourth aperture axes, respectively. Such aperture axes have a fixed positional relationship with respect to the axis of rotation. In a highly preferred embodiment, such positional relationship of the aperture axes to the axis of rotation is substantially parallel thereto.




More particularly, such aperture axes define an arc of a circle. The outlet aperture extends along an outlet axis coincident with the circle center. (It is to be appreciated that in other valve embodiments involving, for example, a rotary or linearly sliding distributor, the positional relationship of the aperture axes to the axis of rotation may be angular thereto.




Yet other aspects of the invention involve additional features of the product selecting valve. As to one such feature, the valve has a dynamic sealing surface coacting between the body and the distributor. At least the first aperture axis is substantially parallel to the axis of rotation and the sealing surface is on an O-ring lodged between the body and the distributor. Such O-ring extends around the first aperture axis.




Other details of the invention are set forth in the following detailed description and in the drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is representative perspective view of the new pressure washer. Parts are broken away.





FIG. 2

is a pictorial view of the primary operative components of the pressure washer of FIG.


1


. Parts are broken away.





FIG. 3

is a diagrammatic view of components shown in FIG.


2


.





FIG. 4

is an elevation view of aspects of the operating console of the pressure washer of FIG.


1


.





FIG. 5

is a cross-sectional elevation view of the rotary product selecting valve shown in

FIGS. 2 and 3

.





FIG. 6

is a cross-sectional elevation view of the housing of the product selecting valve shown in FIG.


5


.





FIG. 7

is an elevation view, in full representation, of the housing shown in

FIG. 6

taken in the viewing plane


7





7


thereof.





FIG. 8

is an elevation view, in full representation, of the housing shown in

FIG. 6

taken in the viewing plane


8





8


thereof.





FIG. 9

is a cross-sectional elevation view of the cover of the product selecting valve shown in FIG.


5


.





FIG. 10

is an elevation view, in full representation, of the cover shown in

FIG. 9

taken in the viewing plane


10





10


thereof.





FIG. 11

is an elevation view, in full representation, of the cover shown in

FIG. 9

taken in the viewing plane


11





11


thereof.





FIG. 12

is a cross-sectional elevation view of the rotatable distributor of the product selecting valve shown in FIG.


5


.





FIG. 13

is an elevation view, in full representation, of the distributor shown in

FIG. 12

taken in the viewing plane


13





13


thereof.





FIG. 14

is an elevation view, in full representation, of the distributor shown in

FIG. 12

taken in the viewing plane


14





14


thereof.





FIG. 15

is a representative perspective view of another embodiment of a rotary product selecting valve which is similar to the product selecting valve shown in

FIGS. 2 and 5

.





FIG. 16

is a representative perspective view, in exploded form, of a linear, sliding type of product selecting valve.





FIG. 17

is a sectional elevation view of a typical container used with the pressure washer.











DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS




Referring first to

FIGS. 1 through 4

, aspects of the invention involve a pressure washer


10


having a wheeled chassis


11


as well as a liquid pump


13


, a pump-driving prime mover


15


(e.g., an internal combustion engine), and a liquid container (such as container C


1


), all supported by the chassis


11


. The pump


13


has a water inlet port


17


and is coupled to a mixing device


19


such as a venturi-type eductor mixer.




A highly preferred washer


10


has first, second, third and fourth containers C


1


, C


2


, C


3


, C


4


, respectively. All of the containers C


1


, C


2


, C


3


, C


4


as well as the product selecting valve


21


are supported on and by the chassis


11


. The multi-container, valve-equipped pressure washer


10


permits the user to select (by valve manipulation) any one of several chemical products, e.g., a detergent product, a car wash product, a deck wash product, an automobile wax product, or a multi-purpose cleaning product. In a specific embodiment of the washer


10


, each of the first, second and third containers C


1


, C


2


, C


3


contains or is intended to contain within it a different washing or waxing product (and, preferably, is suitably marked to designate such product). The fourth container C


4


has “rinse-out” water in it and is so designated. In the pressure washer console


23


depicted in

FIG. 4

, the products (rather than the containers) are identified by the designators A, B and C adjacent to the selector device


25


.




The mixing device


19


mixes the selected product with high-pressure water (flowing from the garden hose and pressurized by the pump


13


) in appropriate proportion to form a washing or waxing solution of proper “strength.” The solution is then directed along a hose


27


to a spray wand


29


. Notably, the new pressure washer


10


is configured to permit one to use the rinse-out water in the fourth container C


4


to wash a product out of a conduit


31


and the valve


21


using fresh water. Such “washing out” is highly preferred before selecting another product to be mixed with the pumped water.




Referring particularly to

FIGS. 1

,


2


and


17


, each of the containers C


1


, C


2


, C


3


, C


4


includes a top fill neck


33


and a neck cap or closure


35


. The closures


35


are “top-exposed,” thereby providing free access to the containers closures


35


for easy container filling. (Top-exposed closures


35


means closures


35


which are accessible for removal and pouring into the related container C


1


, C


2


, C


3


and/or C


4


without moving or removing any other component of the pressure washer


10


.) And in a specific embodiment, the containers C


1


, C


2


, C


3


, C


4


are of the same size and shape and the closures


35


are in registry with the same horizontal plane


37


.




Referring particularly to

FIGS. 2 and 17

, a container such as container C


1


has a pair of mounting ears


173


, a lower tank connection bushing


175


and an outlet filter


177


. It has been found that when the prime mover


15


is an internal combustion engine, the modest vibration causes a chemical product to splash past a closure


35


. To substantially prevent this eventuality, at least each of the chemical product containers has therewithin a flexible, free-floating baffle member


179


. Such baffle member, a pad made of rubber-like foam or the like, has a density well less than that of water (or of a chemical product) and floats thereon. The member


179


is placed in the container by crumpling it into a ball and pushing it through the neck


33


, whereupon it resumes its original size and shape.




Referring now to

FIGS. 1 and 4

, a highly preferred pressure washer


10


has features which make the washer


10


very easy to use. As examples, the washer


10


has a control console


23


with a constituent selector device


25


and a pressure selector device


39


mounted on such console


23


. In a specific embodiment, the constituent selector device


25


is a rotary knob and the pressure selector device


39


is a lever, e.g., a linearly actuated lever, which moves along a slot


41


and controls the throttle of the prime mover engine. Most preferably, the console


23


includes a graph


43


just above the pressure selector device


39


that visually indicates increasing pressure even though such device


39


controls the engine throttle. (Pressure along the hose


27


and at the wand


29


is generally proportional to the speed at which the pump


13


is driven.)




Further details of the product selecting valve


21


will now be set forth. Referring also to FIGS.


2


and


5


-


14


, the valve


21


has a housing


45


and a housing cover


47


. The housing


45


has a generally cylindrical cavity


49


formed in it and as further described below, a distributor


51


rotates in the cavity


49


. Formed in the cavity floor


53


are first, second, third and fourth inlet apertures


55


,


57


,


59


,


61


, respectively. Each aperture


55


,


57


,


59


,


61


is surrounded by a separate O-ring groove and such grooves are identified as first, second, third and fourth grooves


65


,


67


,


69


,


71


, respectively. The housing


45


also has an outlet aperture


73


surrounded by another O-ring groove, i.e., a fifth groove


75


. The cavity


49


is bounded in part by a circumferential lip


77


and an O-ring groove


79


is formed in such lip


77


. When the cover


47


and the housing


45


are assembled to one another as shown in

FIG. 5

, the O-ring


81


in the groove


79


seals between the housing


45


and cover


47


.




In the specific embodiment shown in

FIGS. 5 through 14

, the inlet apertures


55


,


57


,


59


,


61


extend along respective inlet axes


83


,


85


,


87


,


89


and such axes


83


,


85


,


87


,


89


are equidistant from the outlet axis


91


. To state it another way, the inlet axes


83


,


85


,


87


,


89


define an arc


93


of a circle and the outlet axis


91


is at the circle center. And the axes


83


,


85


,


86


,


89


are parallel to one another.




Referring now to FIGS.


5


and


12


-


14


the valve distributor


51


, sometimes referred to as a rotor in the illustrated embodiment, is lodged between the housing


45


and cover


47


and is rotatable with respect to both. The distributor


51


has a generally planar face


95


which bears against the housing


45


and the O-rings


81


in the grooves


65


,


67


,


69


,


71


,


75


and such face


95


is substantially perpendicular to the distributor axis of rotation


97


. The distributor


51


also includes a circular shoulder


99


which bears against the cover


47


. A ring-like, circumferential bearing surface


101


extends generally between the shoulder


99


and the face


95


. The face


95


, shoulder


99


and bearing surface


101


may be considered to be dynamic sealing surfaces since they seal during movement of distributor


51


with respect to the housing


45


and cover


47


.




Referring particularly to FIGS.


5


and


12


-


14


, the distributor


51


has an aperture connection channel


103


, comprising paths


105


,


107


and


109


which selectively connects one of the inlet apertures


55


,


57


,


59


,


61


to the outlet aperture


73


, depending upon the particular position to which the distributor


51


has been rotated. (Those portions of the paths


107


,


109


at the locations


111


,


113


, respectively, do not form part of the channel


103


and play no role in aperture interconnection.)




Referring also to

FIGS. 2

,


3


,


5


and


12


-


14


, the distributor stem


115


has the selector device


25


mounted thereon. When the distributor


51


is set to connect a particular container C


1


, C


2


, C


3


, C


4


to the mixing device


19


, it is preferred that the distributor


51


be restrained from moving from the selected position. To that end, the valve


21


includes a position retention mechanism


117


coacting between the distributor


51


and the cover


47


. In an exemplary embodiment, the position retention mechanism


117


includes a blind hole


119


(“blind” in that such hole


119


is open at only one end) in which is lodged a compression spring


121


and a ball


123


urged toward the cover


47


by such spring


121


. The cover


47


has a plurality of shallow detent pockets


125


,


127


,


129


,


131


and when the path


105


is aligned with a particular inlet aperture


55


,


57


,


59


or


61


, the ball is aligned with a corresponding pocket


131


,


129


,


127


,


125


, respectively. When the selector device


25


is in the OFF position (see FIG.


4


), the ball


123


is aligned with the pocket


133


.




Conveniently, the new valve


21


also includes structure which limits angular rotation of the distributor


51


. Referring to

FIGS. 11 and 13

, the distributor


51


has a tang


135


protruding in the direction of the stem


115


and the cover


47


includes an arcuate stop groove


137


into which the tang


135


extends and in which the tang


135


moves. In a specific embodiment, the stop groove


137


has an arc length of about 210°. That is, radii extending from the cover center through respective ends of the groove define an arc of about 210° therebetween. When the valve


21


is so configured, the tang


135


and groove


137


cooperate to limit rotational travel of the distributor


51


to about 210°.




Referring now to

FIGS. 2 and 3

, each of the containers C


1


, C


2


, C


3


, C


4


is attached to a separate valve conduit extending to the valve


21


. Herein, such conduits are referred to as first, second, third and fourth conduits


139


,


141


,


143


,


145


, respectively, and in the assembled ready-to-use valve, the conduits


139


,


141


,


143


,


145


are attached to the inlet apertures


55


,


57


,


59


,


61


, respectively. And the output or device conduit


31


is connected to and extends between the outlet aperture


73


and the mixing device


19


.




In use, each of three different constituents is placed in the containers C


1


, C


2


and C


3


and water is placed in the container C


4


. The selector device


25


is rotated to select one of containers and a constituent or water flows from one of the containers C


1


, C


2


, C


3


or C


4


along one of the conduits


139


,


141


,


143


or


145


is mixed in the device


19


with water from the pump


13


and delivered to the wand


29


for washing, waxing or the like. Before selecting another constituent, the device


25


is rotated to select the water container C


4


to wash out the channel


103


and the outlet aperture


73


and conduit


31


. Thereafter, another constituent may be selected by device rotation. (No doubt, it is appreciated that the pressure washer


10


can be used with but a single constituent in any one of the containers C


1


, C


2


, C


3


. Preferably, no liquid other than water is placed in container C


4


.)




As described above, the highly preferred valve


21


is a rotary valve having axially-oriented inlet apertures


55


,


57


,


59


,


61


. Referring to

FIG. 15

, the rotary valve


21




a


may also be configured with radially-oriented inlet apertures


55




a,




57




a,




59




a,




61




a


and an axial outlet aperture


73




a.






But a rotary valve


21


,


21




a


is not the only type of valve suitable for use with the pressure washer


10


. Referring to

FIG. 16

, a simplified, linearly-actuated slider valve


21




b


has a manifold plate


149


in which each inlet aperture


55




b,




57




b,




59




b,




61




b


connects via a right-angle channel represented by dashed lines to a corresponding port


151


,


153


,


155


,


157


. An output plate


159


has an elongate channel


161


which is in registry with the ports when the valve


21




b


is assembled.




A selector plate


163


is mounted for sliding movement between the plates


149


,


159


which are not relatively movable with respect to one another. The selector plate


163


has a pickup aperture


165


which is in registry with one of the ports


151


,


153


,


155


,


157


, depending upon the position of the plate


163


. Irrespective of the position of the selector plate


163


, the pickup aperture


165


is always in registry with the channel


161


. Liquid entering any one of the apertures


55




b,




57




b,




59




b,




61




b


is thereby connected vi the channel


161


, to the outlet aperture


167


in the plate


159


.




While the principles of the invention are shown and described in connection with preferred embodiments, it is to be understood clearly that such embodiments are by way of example and are not limiting.



Claims
  • 1. A pressure washer comprising:a single pump fluidly connected to a primary water source; a mixing device fluidly connected to the pump; a valve including a device conduit fluidly connected to the mixing device; first and second containers having respective first and second chemical products therein, a first conduit fluidly connecting the first container to the valve; a second conduit fluidly connecting the second container to the valve; and a wash out assembly including a third container having water and a third conduit fluidly connecting the third container to the valve, wherein the valve is fluidly connected between the first, second, and third containers and the mixing device, the valve being adjustable to selectively place one of the first, second, and third containers in fluid flow communication with the mixing device through the device conduit such that the valve can be adjusted to fluidly connect the wash out assembly with the mixing device to flush out the valve and device conduit.
  • 2. The pressure washer of claim 1, wherein the pump is fluidly connected to a water source.
  • 3. The pressure washer of claim 1, wherein the mixing device is a venturi-type eductor mixer.
  • 4. The pressure washer of claim 1, further comprising a chassis, wherein the pump, valve, and container are supported by the chassis.
  • 5. The pressure washer of claim 1, wherein the chemical product of the first container is one of a detergent product, a car wash product, a deck wash product, an automobile wax product, and a multipurpose cleaning product, and the chemical product of the second container is a different one of a detergent product, a car wash product, a deck wash product, an automobile wax product, and a multipurpose cleaning product.
  • 6. The pressure washer of claim 1, wherein the valve includes a valve body that is connected to the first, second, and third valve conduits and a distributor that is connected to the device conduit and mounted for movement relative to the valve body.
  • 7. The pressure washer of claim 6, wherein the distributor includes a channel for selectively fluidly connecting one of the first, second, and third container to the mixing device.
  • 8. The pressure washer of claim 6, wherein the valve includes a position retention mechanism between the distributor and the valve body to maintain the distributor at a selected position.
  • 9. The pressure washer of claim 6, further comprising a pump driving prime mover that drives the pump and includes a throttle, the pressure washer further comprising a control console including a product selector device and a pressure selector device, wherein the product selector device is coupled to the control console and the distributor and adjusts the valve, and the pressure selector device is coupled to the control console and the throttle of the pump driving prime mover and adjusts the speed of the motor and the pump.
  • 10. The pressure washer of claim 9, wherein the product selector device is a manually adjusted rotary knob.
  • 11. The pressure washer of claim 9, wherein the pressure selector device is a manually linearly-actuated lever.
  • 12. A method for washing out a pressure washer that includes a single pump fluidly connected to a primary water source, a mixing device that is fluidly connected to the pump, a valve having a device conduit fluidly connected to the mixing device, first and second containers having respective first and second chemical products therein, a first conduit fluidly connecting the first container to the valve, and a second conduit fluidly connecting the second container to the valve, the method comprising:providing a wash out assembly including a third container having water and a third conduit fluidly connecting the third container to the valve; adjusting the valve to direct the first chemical product from the first container, through the first conduit, valve, and device conduit, and into the mixing device; adjusting the valve to direct water from the wash out assembly, through the valve and device conduit, and into the mixing device to wash out the first chemical product from the valve and the device conduit; adjusting the valve to direct the second chemical product from the second container, through the second conduit, valve, and device conduit, and into the mixing device; pumping water from the primary water source; and mixing the second chemical product with the water from the primary water source within the mixing device.
  • 13. The method of claim 12, further comprising mixing within the mixing device one of the first chemical product from the first container, the second chemical product from the second container, and the water from the washout assembly with water being pumped by the pump from a water source.
Parent Case Info

This application is a continuation of application Ser. No. 09/246,886, filed Feb. 8, 1999, the entire content of which is incorporated herein by reference now abandoned.

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5409032 Berfield Apr 1995 A
5421900 Clontz Jun 1995 A
5584327 Thomas et al. Dec 1996 A
5653261 Dalhart et al. Aug 1997 A
5718255 Gilpatrick et al. Feb 1998 A
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5996907 Toetschinger et al. Dec 1999 A
Continuations (1)
Number Date Country
Parent 09/246886 Feb 1999 US
Child 09/999421 US