U.S. patent application number 11/367117 was filed with the patent office on 2007-09-06 for engine shroud.
Invention is credited to Klaus K. Hahn, Clinton C. Thackery.
Application Number | 20070207042 11/367117 |
Document ID | / |
Family ID | 38226507 |
Filed Date | 2007-09-06 |
United States Patent
Application |
20070207042 |
Kind Code |
A1 |
Hahn; Klaus K. ; et
al. |
September 6, 2007 |
Engine shroud
Abstract
A machine is provided that includes an engine that rotates an
operating member. Each of the engine and the operating member is
supported on a frame that supports each of the engine and the
operating member. A shroud is mounted to the frame independently of
the engine and the operating member and the shroud substantially
encloses at least a portion of the engine.
Inventors: |
Hahn; Klaus K.; (Braselton,
GA) ; Thackery; Clinton C.; (Anderson, SC) |
Correspondence
Address: |
BRINKS HOFER GILSON & LIONE
P.O. BOX 10395
CHICAGO
IL
60610
US
|
Family ID: |
38226507 |
Appl. No.: |
11/367117 |
Filed: |
March 3, 2006 |
Current U.S.
Class: |
417/234 ;
417/364 |
Current CPC
Class: |
B08B 3/026 20130101;
B08B 2203/0211 20130101 |
Class at
Publication: |
417/234 ;
417/364 |
International
Class: |
F04B 53/00 20060101
F04B053/00 |
Claims
1. A pressure washer comprising: (a) an engine that is operatively
connected to a pump; (b) a frame that supports each of the engine
and the pump; and (c) a shroud mounted to the frame independently
of the engine and the pump, wherein the shroud at least partially
encloses the engine.
2. The pressure washer of claim 1 wherein the shroud substantially
encloses the engine and the pump.
3. The pressure washer of claim 1 wherein the shroud further
comprises a plurality of vents to define an air flow passage to and
from the engine.
4. The pressure washer of claim 1 wherein the shroud is mounted to
the frame with at least one dampener to limit vibrations generated
by the pump and the engine.
5. The pressure washer of claim 4 wherein the dampeners are
rubber.
6. The pressure washer of claim 1 wherein the shroud is
plastic.
7. The pressure washer of claim 1 wherein the shroud is mounted to
the frame at a plurality of discrete locations.
8. The pressure washer of claim 1 wherein the engine and the pump
are each mounted to the frame with at least one dampener to limit
vibrations transferred to the frame.
9. The pressure washer of claim 1 wherein the shroud further
comprises at least one retainer to receive and support tools for
use with the pressure washer.
10. The pressure washer of claim 9 wherein the at least one
retainer is integrally formed with the shroud.
11. The pressure washer of claim 9 wherein the at least one
retainer is formed separately from the shroud and connected to the
shroud.
12. The pressure washer of claim 1 wherein the shroud does not
contact the engine or the pump when attached to the frame.
13. A machine comprising: (a) an engine that rotates an operating
member; (b) a frame that supports each of the engine and the
operating member; and (c) a shroud mounted to the frame
independently of the engine and the operating member, wherein the
shroud substantially encloses a portion of either the engine or the
operating member.
14. The machine of claim 13 wherein the shroud has at least one
vent to define an air flow passage to and from the engine from
outside the shroud.
15. The machine of claim 13 wherein the shroud is mounted to the
frame with structure to attenuate the vibrations generated by the
engine and the operating member.
16. The machine of claim 13 wherein the shroud further comprises at
least one retainer to receive and support tools for use with the
machine.
17. The machine of claim 16 wherein the at least one retainer is
integrally formed with the shroud.
18. The machine of claim 16 wherein the at least one retainer is
formed separately from the shroud and connected to the shroud.
19. The machine of claim 13 wherein the shroud does not contact the
engine or the operating member when mounted to the frame.
20. The machine of claim 13 wherein the machine is a generator.
21. The machine of claim 13 wherein the machine is an air
compressor.
22. A pressure washer comprising: (a) an engine that is operatively
connected to a pump; (b) a frame that supports each of the engine
and the pump; and (c) a shroud mounted to the frame independently
of the engine and the pump with structure to limit the vibrations
produced in the engine or the pump, wherein the shroud at least
partially encloses the engine and includes at least one retainer to
accept and retain a tool for use with the pressure washer.
23. The pressure washer of claim 22 wherein the shroud is mounted
to the frame at a plurality of locations.
Description
BACKGROUND
[0001] The present invention relates to portable machines with fuel
powered engines, and specifically to portable pressure washers with
fuel powered engines.
[0002] One side effect of using a fuel powered engine to operate a
pressure washer is that the engine generates a significant amount
of heat during operation due to the combustion process. This
generated heat causes the engine's exterior surfaces to become
extremely hot during operation such that a user could easily become
burned if directly contacting an exposed engine surface. Prior art
pressure washers have used various covers or shrouds to enclose the
engine to prevent users from contacting the engine. Because the
covers are generally attached directly to the surface of the
engine, the cover must be manufactured from a material with
specific properties that allow the cover to accept the significant
amount of heat transferred to it from the engine, or in the
alternative, the dimensions of the cover (i.e. the thickness of the
cover) must be such that the cover can accept the amount of heat
generated and transferred to the cover.
[0003] Because covers for pressure washers must be robust enough to
accept a significant amount of heat from an engine, it is often a
design challenge to provide structures or components to store
external tools that may be used with the pressure washer. Many
current pressure washers have been designed to include a plurality
of clips, rings, or other structures to retain external tools for
use with the pressure washer, such as lances, spray guns, cords,
nozzles, etc. The structures provided to store these tools is often
attached to the handle, the cart, or other working parts of the
pressure washer. Storing external components on these portions of
the pressure washer makes the pressure washer bulkier and less
maneuverable with the external tools installed than many users
would prefer.
[0004] Because of heat or vibrational concerns, many previous
shrouds that were mounted directly to the engine could not be
formed to accept and retain external tools because of material
considerations. Specifically, shrouds or covers that are mounted on
an engine receive a significant amount of heat from the engine
during operation and accordingly reach dramatically higher
temperatures. Accordingly, shrouds were often manufactured with
relatively thick or relatively heat resistant materials to
withstand the increased temperatures. The design requirements for
previous shrouds that were directly connected to an engine often
prevented the shroud from including structures that were movable or
had sufficient elasticity to accept and retain a tool such as a
spray gun.
[0005] Additionally, shrouds that are directly mounted to an engine
receive a portion or percentage of any vibrations created by the
engine or pump during operation. Any external tools that are
attached to the shroud receive any vibrations within the shroud and
may become at least partially unstable with respect to the shroud
during pressure washer operation. This unstable connection could
lead to failure or breakage of the structures used to removeably
accept the external tools, which reduces the operability and
convenience of operating the pressure washer. Additionally, the
relative movement between the vibrating shroud and the external
tools during operation (because the external tools do not vibrate
with the same harmonic frequency as the shroud because of their
inertia) may create additional unpleasant noise, which often serves
as a distraction and an annoyance to the user.
BRIEF SUMMARY
[0006] A pressure washer is provided that includes an engine that
is operatively connected to a pump. Each of the engine and the pump
are supported on a frame. A shroud is mounted to the frame
independently of the engine and the pump wherein the shroud at
least partially surrounds and encloses a portion of the engine.
[0007] Advantages of the present invention will become more
apparent to those skilled in the art from the following description
of the preferred embodiments of the invention that have been shown
and described by way of illustration. As will be realized, the
invention is capable of other and different embodiments, and its
details are capable of modification in various respects.
Accordingly, the drawings and description are to be regarded as
illustrative in nature and not as restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The features and advantages of the present invention may be
better understood by reference to the accompanying drawings in
which like reference numerals refer to like elements.
[0009] FIG. 1 is a perspective view of a pressure washer of the
present invention.
[0010] FIG. 2 is the perspective view of FIG. 1 showing the
pressure washer without the external tools attached to the
shroud.
[0011] FIG. 3 is a perspective exploded view of the shroud and
external tools.
[0012] FIG. 4 is a right side view of the pressure washer of FIG.
1.
[0013] FIG. 5 is a front side view of the pressure washer of FIG.
1.
[0014] FIG. 6 is a top view of the pressure washer of FIG. 1.
[0015] FIG. 7 is a back view of the pressure washer of FIG. 1.
[0016] FIG. 8 is a perspective view of a second embodiment of the
pressure washer of the present invention.
[0017] FIG. 9 is an exploded view of the pressure washer of FIG.
8.
DETAILED DESCRIPTION
[0018] While this invention is susceptible of several different
embodiments, this specification and the accompanying drawings
disclose only some specific forms as examples of the invention. The
invention is not intended to be limited by the descriptions in this
specification or the drawings. Instead, the scope of the invention
is provided in the claims.
[0019] Referring now to the figures, a shroud for a machine is
provided. The shroud described below can be implemented with a
multitude of different types of machines that include engines to
operate a working member to perform a specific task. Additionally,
the shroud described below may be implemented on various machines
that include fuel powered engines, such as pressure washers,
generators, or air compressors. Although the invention may be
implemented with a variety of different types of machines, the
design is fully described with specific references to use in a
pressure washer. For the sake of brevity we do not fully describe
the use of this concept with other types of machines although one
of skill in the art, after fully reviewing the specification and
drawings herein, will comprehend that this disclosure may
successfully be implemented with other types of machines.
[0020] Turning now to FIG. 1, a pressure washer 10 is provided. The
pressure washer 10 is used to receive liquid at a relatively low
pressure and raise the pressure using a pump 46, or similar device,
until the liquid pressure is such that the liquid may be projected
from a spray gun 92, or similar device, at a high rate of speed and
pressure. The liquid projected from the pressure washer 10 may be
used for various operations. Often, pressure washers are located on
a wheeled cart or other movable apparatus to allow the pressure
washer to be transported to remote locations for use. The pump 46
on a pressure washer is often operated by a fuel powered engine 40
that includes a rotating drive shaft that is coupled with the pump
46 to rotate a pump impeller (not shown). In some embodiments, the
fuel powered engine 40 may be an internal combustion engine.
[0021] As understood by those of ordinary skill in the art, a fuel
powered engine generates a large amount of heat during operation
due to fuel combustion. While engines are provided with mechanisms
for cooling, such as fins 42 and air flow (whether forced or
natural circulation) past the external surfaces of the engine,
these cooling mechanisms are not normally efficient enough to
prevent the exterior surfaces of the engine 40 from dramatically
increasing in temperature during engine operation. Accordingly,
because the engine 40 is at an increased temperature during
operation, the excess heat present on the exterior surfaces of the
engine is transferred to neighboring components due to radiation
and convection heat transfer, and transferred to components that
are in contact with the engine surface due to conduction heat
transfer. Therefore, components of the pressure washer that are in
contact with or simply in close proximity to the engine 40
experience a significant amount of heat from the engine 40 during
operation and accordingly reach higher temperatures during engine
operation.
[0022] The engine 40 and associated components such as the fuel
tank 14 and the pump 46 are normally rigidly mounted on the frame
60. The frame 40 additionally serves as the mounting point for a
pair of wheels 12, a plurality of stops 13, a handle 14, and a
shroud or cover 50. The wheels 12 may be mounted independently of
each other to the frame, or in other embodiments, the wheels may
rotate together on an axle (not shown) that is rotatably mounted to
the frame 60. The handle 14 serves as the structure to manipulate
when moving the pressure washer 10.
[0023] The frame 60 may be formed from metal and may preferably be
formed with hollow metal tubing for high suitable strength but
limited weight and material requirements. As shown in the figures,
the frame 60 includes a vertical rear section 62, a bottom section
63, and a top section 64. The rear section 62 includes two vertical
posts 62a and a horizontal cross-member 62b (FIG. 7). The wheels 12
rotate about axles that are rotatably mounted to each of the
vertical posts 62a. The rear section 62 additionally includes a
handle 14 that is collapsible into the vertical posts 62a and can
be locked in the extended position shown in the figures with a knob
14b on each vertical post 62a.
[0024] The bottom section 63 includes two arms 63a, each extending
from a respective one of the vertical posts 62a. The bottom section
63 additionally includes a front cross-member 63b that connects the
two arms 63a and is at substantially the same height as the
cross-member 62b of the rear section 62. Finally, the top section
64 includes two arms 64a that extend from one of the two vertical
posts 62a of the rear section 62. The arms 64a extend substantially
perpendicularly from the vertical posts 62a and curve slightly
downward as they project toward the front end of the machine. The
two arms 64a are connected at the front end with a cross-member
64b.
[0025] A mounting plate 65 may be attached to the cross-member 62b
of the rear section and the cross-member 63b of the bottom section
63. The mounting plate 65 accepts and stabilizes the engine 40
above the mounting plate (and below the top section 64 of the frame
60) and includes an aperture (not shown) to operatively connect the
pump 46 with the engine 40. The pump 46 extends from the engine 40
below the mounting plate 65a. As shown in FIG. 1, the mounting
plate 65 is mounted to the frame 60 with a plurality of fasteners
66. Additionally, the forward and rear ends 65a, 65b (FIG. 7) of
the mounting plate 65 are curved to match the curvature of the
frame 60 for a stable connection. Additionally, dampening material
(not shown), such as rubber, may be positioned between the mounting
plate 65 and the frame 60 to attenuate any vibrations present in
the mounting plate 65 from the engine 40 or pump 46 to reduce their
transfer to the frame. Additionally, the dampening material may
have a relatively high thermal conductivity to substantially
prevent heat in the mounting plate 65 from transferring to the
frame 60 through conduction.
[0026] The shroud 50 is mounted to the frame 60 independently of
the engine 40 and the pump 46. The shroud 50 is provided on the
pressure washer 10 to at least partially enclose the engine 40 to
provide a protective barrier against accidental contact with the
engine 40 during operation that could lead to burns or other
injuries. As shown in FIG. 1, the shroud 50 is located above the
engine 40 and is mounted to the frame 60.
[0027] The shroud 50 is mounted directly to the frame 60 and does
not contact the engine 40 or any associated components. As can be
understood by those of ordinary skill in the art, because there is
no direct connection contact between the engine 40 and the shroud
50, there is no direct path for conduction heat transfer between
the two components. This significantly reduces the amount of heat
that can be transferred to the shroud 50, and accordingly reduces
the maximum temperature of the shroud during pressure washer 10
operations.
[0028] The shroud 50 may be mounted to the frame 60 at multiple
locations to increase the stability of the shroud 60. As best shown
in FIG. 2, the shroud 50 has a plurality of extending flanges 58
that provide the connection with the frame 60. As shown, the
flanges 58 may have a curved bottom surface or profile to closely
contact the curved frame 60. Each flange 58 has an aperture 58a
(FIG. 3) to accept a fastener for insertion into a corresponding
hole in the frame 60.
[0029] A dampener 62, such as a layer of rubber or other similar
material, may be provided between the frame 60 and the shroud 50 at
each mounting location. This dampener 62 attenuates or
substantially prevents the transfer of heat from the frame 60 to
the shroud 50 (and vice versa), and also substantially prevents the
transfer of any vibrations that may be present in the frame 60 from
transferring to the shroud 50 (and vice versa). Accordingly,
because the dampeners 62 attenuate or substantially prevent the
transfer of heat and vibrations from the frame to the shroud 50,
the shroud 50 can be designed and manufactured with a broader range
of shapes, sizes, and materials than would be possible if the
shroud 50 reached higher temperatures during pressure washer 10
operation or if the shroud 50 was subject to vibrations of a larger
magnitude.
[0030] As best understood with reference to FIGS. 1-3, the shroud
50 may include a plurality of receptacles 56 to accept and retain
tools for use with the pressure washer 10. Specifically, the shroud
50 may include a hole 55a for receiving a spray gun 92, a
receptacle 56a for a lance 94, and a plurality of receptacles 56c
to receive spray nozzles 96. As shown in FIG. 3, the spray gun 92
may include a projection 92a that may be inserted into the hole 55a
in the shroud to connect the spray gun 92 to the shroud 50.
Additionally, a receptacle 56a may be provided that includes a
plurality of fingers 56b to retain the lance 94. As can be
understood, the spray gun 92 can be retained by the shroud 50 using
a similar receptacle 56a as shown in FIG. 3. The receptacle 56a may
be threaded or otherwise inserted into a second hole 55a in the
shroud, or in other embodiments the fingers 56b of the receptacle
may be monolithically formed with the shroud 50.
[0031] As best shown in FIG. 3, a plate 54 may be provided to hold
a plurality of nozzles 96. The plate 54 includes a plurality of
holes 54a that receive the male ends of the nozzles 96 and a
plurality of retaining apertures 54b that are engageable with
fingers 53 on the shroud 50 to retain the plate 54 on the shroud
50. In this embodiment, the plate 54 is easily and quickly
removable from the shroud 50 for convenient use at the worksite. In
other embodiments, the plate 54 may be monolithically formed with
the shroud 50. In other embodiments, the shroud 50 may include
additional or alternate receptacles 56 for other tools or
components for use with the pressure washer 10, or another type of
machine that uses a similar shroud 50. The receptacles 56 may be
integrally formed with the shroud 50, or may be attached to the
shroud 50 after the shroud 50 is formed.
[0032] The shroud 50 may be formed from various materials. The
shroud 50 may be formed from plastic and integrally mounted in a
single piece. The shrouds 50 that are manufactured from plastic may
be conveniently and inexpensively molded as a single component in
the desired shape. As is known to those of ordinary skill in the
art, plastic has a relatively low thermal conductivity.
Additionally, plastic can be molded to be relatively elastic, which
is useful for receptacles 56 that receive some of the pressure
washer tools. For example, as shown in FIGS. 1-3, the receptacles
56a for receiving the lance 94, may be formed from opposing arms
56b that partially surround the outer volume of a portion of the
tool when positioned within the arms 56b. The arms 56b of the
receptacles 56a must be sufficiently flexible because they are
biased away from each other to insert the tool into the receptacle
56a and return to their normal orientation when the tool is fully
inserted within the receptacle 56a. In other embodiments, the
shroud 50 may be formed from metal or other acceptable
materials.
[0033] In addition to providing a plurality of receptacles 56a,
56b, the shroud may include a plurality of vents, or louvers, 70 to
allow air flow through the shroud 50 to interact with the engine
40. The vents 70 formed on the shroud 50 may be positioned to allow
inlet and exhaust air to flow to and from the engine in conjunction
with the combustion process. Additionally, vents 70 may be used to
allow air flow past the engine 40 during operation (either by
natural or forced air circulation) to remove heat by convection. As
can be understood, the vents 70 can be integrally formed in the
shroud 50 when formed as a molded plastic piece. Alternatively, the
vents 70 can be formed in the shroud 50 after the initial formation
of the shroud 50 in an independent step for shrouds 50 that are
formed from metal or another similar material.
[0034] A second representative embodiment of the machine is shown
in FIGS. 8 and 9. Specifically, these figures show a second
pressure washer 100. The pressure washer 100 includes all of the
components discussed with respect to the first embodiment above,
but substantially encloses the motor 140 (FIG. 9) and the pump (not
shown) with a shroud or cover 150.
[0035] The shroud 150 is formed from multiple pieces, a front
member 151, right and left sides 152, 153, a top member 154, and a
rear member 155. As shown in the exploded view of FIG. 9, the left
and right sides 152, 153 are attached to the frame 160 with
fasteners 180 that are inserted through holes in the shroud members
and into holes 161 in the frame. The top and rear members 154, 155
are mounted to the left and right sides 152, 153 after they are
mounted to the frame 160. The front member 151 is mounted to a
front cross-member 164 of the frame 160 and is kept rigidly mounted
to the pressure washer with the left and right sides 152, 153.
Accordingly, the shroud is mounted to the frame 160 and does not
contact the engine 140 or the pump. Therefore, the pressure washer
of this embodiment includes the advantages of the previous
embodiment. Specifically, there is no path for direct conduction
heat transfer between the engine 140 and the shroud 150.
Additionally, because the shroud 150 is not directly attached to
the engine 140, vibrations are not directly transferred to the
shroud, which allows for quieter and more stable operation of the
pressure washer. As with the embodiment above, in this embodiment,
a dampening material may be positioned between the frame and the
sides of the shroud 150 to attenuate the transfer from any
vibrations in the frame to the shroud 150.
[0036] As with the embodiment discussed above, the shroud 150 may
include a plurality of structures 156 for receiving tools for use
with the pressure washer 100. Specifically, the shroud may receive
a spray gun 92 and a lance 94 as well as a plurality of nozzles 96.
Additionally, the shroud 150 includes a plurality of vents 170
along the sides and top of the shroud 150 to allow air flow past
the engine 140 (that is substantially enclosed within the shroud
150) for cooling as well as air flow for use with the combustion
process.
[0037] The foregoing disclosure is the best mode devised by the
inventors for practicing this invention. It is apparent, however,
that apparatus incorporating modifications and variations will be
obvious to one skilled in the art. Inasmuch as the foregoing
disclosure is intended to enable one skilled in the pertinent art
to practice the instant invention, it should not be construed to be
limited thereby but should be construed to include aforementioned
obvious variations and be limited only by the spirit and scope of
the following claims.
[0038] It is therefore intended that the foregoing detailed
description be regarded as illustrative rather than limiting, and
that it be understood that it is the following claims, including
all equivalents, that are intended to define the spirit and scope
of this invention.
* * * * *