Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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ENGINE PRE-HEATER SYSTEM
This invention relates generally to engine pre-heaters, and more particularly
to an
improved engine pre-heater system for heating engine coolant, and having
easily removable and
replaceable electric heating elements that can be installed or removed easily
from within the
engine pre-heater and having a greater surface area so as to contact the
coolant flowing past and
around it, therefore heating the coolant in a faster and more efficient
manner. The engine pre-
heater is also operably able to heat coolant, engine oil and transmission oil,
therefore warming the
engine in a faster and more efficient manner for quick start-ups.
DESCRIPTION OF THE PRIOR ART
It is well known that engines are difficult to start and subject to excessive
wear when
operated in cold, northern areas. Various kinds of engine pre-heaters that
heat engine coolant
and/or engine oil or fuel have been used to alleviate this problem. However,
these pre-heaters
have not always been reliable, or require the use of natural gas, propane, oil
or other fuels to
operate. As such, these types of devices are not environmentally friendly or
pollution free.
Other types of engine pre-heaters have attempted to circumvent this problem by
utilizing
electrical elements internally positioned within the pre-heater, whereby
coolant can be heated by
the electrical element. United States Patents Nos. 5,408,960 (Woytowich) and
4,770,134
(Foreman et al) are examples of such devices. However, these arrangements
feature electrical
elements that are internally positioned within the tank or chamber, and do not
allow for easy
removal of the electrical element from the pre-heater, should maintenance or
replacement of the
electrical element be required. Usually, removal of such engine preheating
devices (or heating
elements) can only be effected through complete disassembly of the housing or
the destruction
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thereof, should maintenance or replacement of the electrical element be
required. In such
maintenance or replacement situations, the entire pre-heater would be required
to be removed to
access the internal electrical element, thereby making maintenance and
replacement of such pre-
heater components difficult and complicated.
Thus, there is a need for an improved, environmentally friendly engine pre-
heater system
which has a generally uncomplicated and simple design, which may have easily
removable and
replaceable electric heating elements that can be installed or removed easily
from within the
engine pre-heater and which are more durable and reliable to withstand the
constant flow of
coolant flowing around it over time. There is also a further need for an
improved engine pre-
heater system having electric heating elements with a greater surface area so
as to contact the
coolant flowing past and around it, therefore heating the coolant in a faster
and more efficient
manner. There is further a need for an improved engine pre-heater system which
is also operably
able to heat the coolant, engine oil and transmission oil, therefore heating
the coolant and
warming the engine in a faster and more efficient manner for quick start-ups.
In this regard, the
present invention substantially fulfills this need.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved,
environmentally friendly
engine pre-heater system which has a generally uncomplicated and simple
design, which may
have easily removable and replaceable electric heating elements that can be
installed or removed
easily from within the engine pre-heater and which are more durable and
reliable to withstand the
constant flow of coolant flowing around it over time.
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It is another object of the present invention to provide an improved engine
pre-heater
system having electric heating elements with a greater surface area so as to
contact the coolant
flowing past and around it, therefore heating the coolant in a faster and more
efficient manner.
It is another object of the present invention to provide an improved engine
pre-heater
system which is also operably able to heat the coolant, engine oil and
transmission oil, therefore
heating the coolant and warming the engine in a faster and more efficient
manner for quick start-
ups.
According to one aspect of the present invention, there is provided an engine
pre-heater
system for a vehicle comprising a housing having a passage extending
therethrough for permitting
a passage of coolant through the housing, the housing further comprising at
least one opening
defined therein separate from the passage; at least one electric heating
element inserted into the at
least one opening, the at least one electric heating element being removable
without disassembly
of the housing and having a substantially vertical upper stem body and an
elongated lower end
being connected thereto in a substantially perpendicular relationship to the
upper stem body, the
lower end being constructed and arranged for insertion into the at least one
opening and
projecting into the passage whereby the lower end is in direct contact with
the coolant; an
electrical power source constructed and arranged for connection to the heating
element and a
transmission fluid pan of the vehicle to provide electrical power thereto, and
for enabling the
heating element to directly heat the coolant and transmission oil in the
transmission fluid pan of
the vehicle, and wherein the electrical power source further comprises a first
component
positioned on an interior of the cab of the vehicle and a second component
positioned on an
interior of the engine housing for the vehicle, the first component being
detachable from the
second component; and a pump for circulating the coolant.
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According to another aspect of the present invention, there is provided an
engine pre-
heater system for a vehicle comprising a housing having a passage extending
therethrough for
permitting a passage of coolant through the housing, the housing further
comprising at least one
opening defined therein separate from the passage; a pump for circulating the
coolant through the
housing; at least one electric heating element inserted into the at least one
opening, the at least
one electric heating element being removable without disassembly of the
housing and having a
substantially vertical upper stem body and an elongated lower end being
connected thereto in a
substantially perpendicular relationship to the upper stem body, the elongated
lower end being
constructed and arranged for insertion into the at least one opening and
projecting into the passage
whereby the lower end is in direct contact with the coolant, the elongated
lower end having a
tapered front portion for dividing the coolant flowing past in the housing
whereby the divided
coolant is in contact with, and heated by, both sides of an entire length of
the elongated lower
end; an electrical power source constructed and arranged for connection to
each of the heating
element, a transmission fluid pan of the vehicle and a car battery of the
vehicle to provide
electrical power thereto, and for enabling the heating element to directly
heat the coolant and
transmission oil in the transmission fluid pan of the vehicle, and wherein the
electrical power
source further comprises a first component positioned on an interior of the
cab of the vehicle and
a second component positioned on an interior of the engine housing for the
vehicle, the first
component being detachable from the second component; and a remote device for
activating, at a
distance from an interior of the vehicle, the electrical power source to
provide the electrical power
to each of the heating element, the transmission fluid pan of the vehicle and
the car battery of the
vehicle for pre-heating the engine and pre-heating the interior of the cab of
a vehicle when an
engine of the vehicle is not in operation.
According to another aspect of the present invention, there is provided an
engine pre-
heater system for a vehicle comprising a housing interconnected with a
radiator and engine block
of the vehicle to form a fluid flow circuit and having a passage extending
therethrough for
permitting a passage of coolant through the housing, the housing having at
least one opening
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defined thereon which is in communication with the passage; at least one
heating element inserted
into the at least one opening of the housing and having a substantially
vertical upper stem body
and an elongated lower end being connected thereto in a substantially
perpendicular relationship
to the substantially vertical upper stem body, the elongated lower end being
constructed and
arranged for insertion into the at least one opening and projecting into the
passage whereby the
elongated lower end is in direct contact with the coolant in the passage;
wherein the connection
portion of the heating element is made of austenitic nickel chromium-based
super-alloys; and
wherein the substantially vertical upper stem body is accessible from an
exterior surface of the
housing to permit removal of the at least one heating element from the housing
without
disassembly of the housing and without disconnection of the housing from the
fluid flow circuit;
an electrical power source constructed and arranged for connection to the at
least one heating
element to provide electrical power thereto, and for enabling the at least one
heating element to
directly heat the coolant; a pump in communication with the pre-heater system
for continuously
circulating the coolant throughout the fluid flow circuit; and a heat transfer
means connected to
the fluid flow circuit, the heat transfer means being configured to transfer
heat from the heated
coolant flowing in the fluid flow circuit to a space heated by the pre-heater
system; wherein the
electrical power source is at least one of a power pack and an electrical
battery.
According to a further aspect of the present invention, there is provided an
engine pre-
heater system for a vehicle comprising a housing interconnected with a
radiator and engine block
of the vehicle to form a fluid flow circuit and having a passage extending
therethrough for
permitting a passage of coolant through the housing, the housing having at
least one opening
defined thereon which is in communication with the passage; at least one
heating element inserted
into the at least one opening of the housing and having a substantially
vertical upper stem body
and an elongated lower end being connected thereto in a substantially
perpendicular relationship
to the substantially vertical upper stem body, the elongated lower end being
constructed and
arranged for insertion into the at least one opening and projecting into the
passage whereby the
elongated lower end is in direct contact with the coolant in the passage;
wherein the connection
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portion of the heating element is made of austenitic nickel chromium-based
super-alloys; and
wherein the substantially vertical upper stem body is accessible from an
exterior surface of the
housing to permit removal of the at least one heating element from the housing
without
disassembly of the housing and without disconnection of the housing from the
fluid flow circuit;
an electrical power source constructed and arranged for connection to the at
least one heating
element to provide electrical power thereto, and for enabling the at least one
heating element to
directly heat the coolant; a pump in communication with the pre-heater system
for continuously
circulating the coolant throughout the fluid flow circuit; a heat transfer
means connected to the
fluid flow circuit, the heat transfer means being configured to transfer heat
from the heated
coolant flowing in the fluid flow circuit to a space heated by the pre-heater
system; and a remote
device for activating, at a distance from an interior of the vehicle, the
electrical power source to
provide the electrical power to the at least one heating element for pre-
heating the engine and pre-
eating an interior of the vehicle when an engine of the vehicle is not in
operation.
The advantage of the present invention is that it provides an improved,
environmentally
friendly engine pre-heater system which has a generally uncomplicated and
simple design, which
may have easily removable and replaceable electric heating elements that can
be installed or
removed easily from within the engine pre-heater and which are more durable
and reliable to
withstand the constant flow of coolant flowing around it over time.
Yet another advantage of the present invention is to provide an improved
engine pre-
heater system having electric heating elements with a greater surface area so
as to contact the
coolant flowing past and around it, therefore heating the coolant in a faster
and more efficient
manner.
Yet another advantage of the present invention is to provide an improved
engine pre-
heater system which is also operably able to heat the coolant, engine oil and
transmission oil,
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therefore heating the coolant and warming the engine in a faster and more
efficient manner for
quick start-ups.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the present invention is described below with
reference to the
accompanying drawings, in which:
Figure 1 is a perspective view of one embodiment of the housing of the engine
pre-heater,
illustrating the heating elements that are inserted therein to contact coolant
flowing
therethrough;
Figure 2 is a perspective view of an embodiment of an embodiment of a heating
element
that is inserted into the housing of the engine pre-heater of the present
invention;
Figure 3 is a schematic diagram of an embodiment of the engine pre-heater
system of the
present invention in place within a car engine; and
Figure 4 is a perspective view of a further embodiment of an embodiment of a
heating
element that is inserted into the housing of the engine pre-heater of the
present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to Figure 1, there is shown an engine pre-heater system for a
vehicle,
illustrating the heating element which is inserted therein to contact coolant
within the engine pre-
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heater, the engine pre-heater being designated in its entirety by the
reference numeral 1. The pre-
heater 1 is adapted to be attached to an engine (not shown) and connected to
the engine's coolant
system to heat the coolant and thereby keep the engine warm when activated to
ensure a warm
engine upon ignition. The pre-heater 1 comprises a housing 3 having a passage
9 extending
therethrough for passage of coolant (not shown) through the housing. As can be
seen in Figure 1,
the passage 9 of the housing 3 extends substantially horizontally throughout a
length of the
housing. The housing 3 further comprises at least one opening 5 on an upper
surface of the
housing 3, but more preferably, a plurality of openings defined thereon, each
of which are
separate from the passage 9, and each of which define an internally defined
chamber 7 within the
body of the housing 3, into which electric heating elements 11 are inserted
through the opening 5
on the upper surface of the housing 3, so as to reside within the internally
defined chambers 7.
With such heating elements 11, it can be seen that a lower end 25 of the
heating element 11
projects vertically downwards into the passage 9 of the housing 3, whereby the
heating element
11 is in direct contact with the coolant flowing through passage 9, (the
directional passage flow of
the coolant being shown as "A" in Figure 1). As can also be readily seen in
Figure 1, the housing
3 possesses an inlet 2 at one end of the housing, and an outlet 4 at the
opposite end of the housing.
Preferably, the housing 3 is made of metal, though it is conceivable that
other materials could also
be utilized, as would be apparent to one skilled in the art.
As can be seen in Figure 2, there is shown the electric heating element 11
that is inserted
through the opening 5 on the upper surface of the housing 3, so as to reside
within the internally
defined chambers 7 within the body of the housing 3, as noted previously.
Preferably, any of the
electric heating elements 11 are easily removable and replaceable if required.
When positioned
within the internally defined chambers 7 within the body of the housing 3 of
the, engine pre-heater
1, as shown in Figure 1, the electric heating element 11 comprises an
elongated stem 23 that is
inserted into chambers 7 of the housing 3. An upper end of the stem 23
comprises an electrical
connection portion 19, which is connected to, and supplied with, electrical
power from a power
source (not shown) such as a battery for enabling the electric heating element
11 to heat the
coolant (not shown), the coolant of course being circulated by pump (not
shown). The electrical
connection portion 19 will, preferably, be made of Inconel TM, it being
understood that this refers
to a family of austenitic nickel chromium-based super-alloys, which are
typically used in high
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temperature applications. Common trade names for Inconel TM include: Inconel
625 TM, Chronin
625 TM, Altemp 625 TM, Haynes 625 TM, Nickelvac 625 TM and Nicrofer 6020 TM,
for example.
Surrounding a substantially middle portion of the stem 23 and the insulating
sheath 21 is a
threaded portion 17, by which the electric heating element 11 can be
threadably fixed and inserted
into chambers 7 of the housing 3. A lower end 25 of the stem 23 is L-shaped
and projects into the
passage 9 of the housing 3 whereby the electric heating element 11 is in
direct contact with the
coolant, the lower end thus being substantially perpendicular in relationship
to the stem 23 and
the remainder of the heating element 11, giving the lower end 25 of the
heating element 11 a
greater surface area with which to contact, and thus heat the coolant.
The outermost point 27 of the lower end 25 will preferably be tapered, at
least slightly. In
this manner, when the electric heating element 11 is inserted into chambers 7
of the housing 3, so
as to project downwardly into the passage 9 of the housing 3 to be in direct
contact with the
coolant, the tapered outermost point 27 of the lower end 25 will act as a
breakwater to the
onrushing coolant flowing past it in the passage 9, (the directional passage
flow of the coolant
being shown as "A" in Figure 2) separating the coolant and forcing the coolant
to flow past both
sides of the lower end 25. Such a construction is advantageous, when
contrasted to that of a
conventional heating element that merely extends downwardly into the passage,
as when such an
element is vertically positioned to extend downwardly within the passage, the
vertical lower end
is thus subjected to the stress of encountering fully the coolant flowing past
within the passage 9
(the directional passage flow of the coolant being shown as "A" in Figures 1
and 2). Over time,
such a construction means that such a heating element is subjected to greater
structural stresses
than that of the electric heating element 11 of the present invention, and
likely will require more
frequent replacement and potential for breakage.
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Moreover, by virtue of the lower end 25 of the stem 23 being L-shaped, the
lower end 25
possesses a greater surface area with which to contact, and thus heat the
coolant. This effectively
means that coolant can be heated at a faster rate than that accomplished by a
conventional heating
element, since coolant is separated and heated by both sides of the lower end
25, rather than just
encountering, and being heated by, the immediate, and only, surface of a
conventional heating
element projecting downwardly in passage 9 to contact the flow of coolant.
And, by virtue of the
tapered outermost point 27 of the lower end 25 forcing the coolant to flow
past both sides of the
lower end 25, the lower end 25 is thus able to heat such coolant flowing past
it in smaller
quantities, since the coolant is effectively being split in half by the
breakwater qualities of tapered
outermost point 27, and the lower end 25 is effectively in contact with both
halves of the coolant
flowing past it.
Figure 3 represents an electrical schematic diagram of one embodiment of an
arrangement
of the engine pre-heater system of the present invention. In a preferred
embodiment, the engine
pre-heater system of the present invention is designed to be interconnected
with a car radiator 33
and an engine block 31 of a vehicle, the engine pre-heater system operating
essentially as a
distinct flow circuit for transferring coolant around the engine block 31.
This separate flow circuit
interconnects, through piping 35, the pump 14, housing 3, car radiator 33,
electric heating
elements 11, engine block 31 and heat emitting radiator 41.
The electric heating elements 11 in the housing 3 are supplied with electrical
power from
a power source 15 via conventional electrical wiring 49 for enabling the
electric heating elements
11 to heat the coolant (not shown), the coolant of course being circulated by
pump 14. In a
preferred embodiment, the power source 15 is an electrical power pack, though
it is conceivable
that, alternatively, solar power cells, battery power, a/c power or the like
could also be used, as
would be apparent to one skilled in the art. Of course, it would be readily
apparent that such a
power source 15 could also be re-energized or re-charged also, as is known in
the art. In a further
preferred embodiment, the power pack 15 can easily be removed and replaced
from the system, in
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order that a new one can be inserted. It will be understood that the power
pack can be activated by
a conventional switch in the cab of the vehicle, or by remote device, as would
be understood by
one skilled in the art.
It should be understood that the power source 15 also comprises, and is
detachable from,
AC plug 29, the power source 15 being present within the cab or interior of a
vehicle, and the AC
plug 29 being fixedly located adjacent to the cab on an interior of the engine
housing for the
vehicle. In this manner, if the power source 15 (the power pack) is to be
detached from the AC
plug 29 for replacement, the power pack 15 is detached from within the cab of
the vehicle, while
the AC plug 29 remains in place within the interior of the engine housing for
the vehicle. The
replacement power pack would then, of course, be attached to the AC Plug 29
for further use. The
AC plug 29 interconnects, by way of electrical wiring 49, power from the power
source 15 (once
activated) to selectively heat electric heating elements 11, and a further
electrical heating wire 45
also extends to selectively heat a transmission oil pan 39. An additional
electrical heating wire 51
also extends to the car battery 43 to provide 1 amp of power continuously to
the battery to keep
the battery 43 charged. In this manner, when the power source 15 is activated,
the electric heating
elements 11 are utilized to warm the coolant, and transmission oil pan 39 is
also heated to warm
the transmission oil therein.
Piping 35 is joined to the existing engine block 31 and the car radiator 33 to
interconnect
these elements to the housing 3 (holding the electric heating elements 11
therein) and the heat
emitting radiator 41 to form the distinct flow circuit for transferring
coolant therein, such coolant
flow obviously being driven by means of pump 14. Pump 14 also ensures that a
steady flow of
coolant will be continuously passed through the piping 35 so as to enter the
housing 3 to
encounter electric heating elements 11 for heating. Generated heat from the
heated coolant can be
passed through piping 35 to the heat emitting radiator 41, where it is
circulated to the interior or
cab of the vehicle by means of a conventional fan or blower (not shown).
Further, through the
flow of warmed coolant (by way of electric heating elements 11) through the
engine block 31, the
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engine oil pan 47 is also indirectly warmed, whereby warming of the engine can
occur in a faster
and more efficient manner for quick engine start-ups.
As can be seen in Figure 4, there is shown an alternative embodiment of the
electric
heating element 52 that is inserted through the opening 5 on the upper surface
of the housing 3, so
as to reside within the internally defined chambers 7 within the body of the
housing 3, as noted
previously. Preferably, any of the electric heating elements 52 are easily
removable and
replaceable if required. When positioned within the internally defined
chambers 7 within the
body of the housing 3 of the engine pre-heater 1, as shown in Figure 1, the
electric heating
element 52 comprises an elongated stem 59 that is inserted into chambers 7 of
the housing 3. An
upper end of the stem 59 comprises an electrical connection portion 53, which
is connected to,
and supplied with, electrical power from a power source (not shown) such as a
battery for
enabling the electric heating element 52 to heat the coolant (not shown), the
coolant of course
being circulated by pump (not shown). The electrical connection portion 53
will, preferably, be
made of Inconel TM, it being understood that this refers to a family of
austenitic nickel chromium-
based super-alloys, which are typically used in high temperature applications.
Common trade
names for Inconel TM include: Inconel 625 TM, Chronin 625 TM, Altemp 625 TM,
Haynes 625 TM,
Nickelvac 625 TM and Nicrofer 6020 TM, for example.
Surrounding a substantially middle portion of the stem 59 and the insulating
sheath 55 is a
threaded portion 57, by which the electric heating element 52 can be
threadably fixed and inserted
into chambers 7 of the housing 3. A lower end 61 of the stem 59 is
substantially angled at a 45
degree angle and projects into the passage 9 of the housing 3 whereby the
electric heating element
52 is in direct contact with the coolant, the lower end thus being
substantially perpendicular in
relationship to the stem 59 and the remainder of the heating element 52,
giving the lower end 61
of the heating element 52 a greater surface area with which to contact, and
thus heat the coolant.
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The outermost point 63 of the lower end 61 will preferably be tapered, at
least slightly. In
this manner, when the electric heating element 52 is inserted into chambers 7
of the housing 3, so
as to project downwardly into the passage 9 of the housing 3 to be in direct
contact with the
coolant, the tapered outermost point 63 of the lower end 61 will act as a
breakwater to the
onrushing coolant flowing past it in the passage 9, (the directional passage
flow of the coolant
being shown as "A" in Figure 4) separating the coolant and forcing the coolant
to flow past both
sides of the lower end 61. Such a construction is advantageous, when
contrasted to that of a
conventional heating element that merely extends downwardly into the passage,
as when such an
element is vertically positioned to extend downwardly within the passage, the
vertical lower end
is thus subjected to the stress of encountering fully the coolant flowing past
within the passage 9
(the directional passage flow of the coolant being shown as "A" in Figures 1,
2 and 4). Over
time, such a construction means that such a heating element is subjected to
greater structural
stresses than that of this embodiment of the electric heating element 52 of
the present invention,
and likely will require more frequent replacement and potential for breakage.
Moreover, by virtue of the lower end 61 of the stem 59 being substantially
angled at a 45
degree angle, the lower end 61 possesses a greater surface area with which to
contact, and thus
heat the coolant. This effectively means that coolant can be heated at a
faster rate than that
accomplished by a conventional heating element, since coolant is separated and
heated by both
sides of the lower end 61, rather than just encountering, and being heated by,
the immediate, and
only, surface of a conventional heating element projecting downwardly in
passage 9 to contact
the flow of coolant. And, by virtue of the tapered outeimost point 63 of the
lower end 61 forcing
the coolant to flow past both sides of the lower end 61, the lower end 61 is
thus able to heat such
coolant flowing past it in smaller quantities, since the coolant is
effectively being split in half by
the breakwater qualities of tapered outermost point 63, and the lower end 61
is effectively in
contact with both halves of the coolant flowing past it. It will of course be
understood that the
lower end of the stem the electric heating element can be substantially angled
at from between a
45 degree angle to a 90 degree angle when it is inserted into the housing to
project into the
passage.
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The engine pre-heater system can be activated by a remote device (not shown)
by a user,
whereby the power source 15 can be activated to heat the electric heating
elements 11, and the
interconnected system, remotely at a distance from the vehicle, and this heat
can then be
transferred by way of the heat emitting radiator 41 into the cab or interior
of the vehicle, pre-
warming the engine and pre-heating the inside of the vehicle.
In another alternative embodiment of the present invention, coolant can be
omitted, and
dry heat, provided from the electric heating elements 11, can be utilized. In
this embodiment
(not shown) the housing would preferably have an air passageway extending
therethrough for
passage of air through the housing, the housing further comprising openings
defined therein
separate from the air passageway. Electric heating elements would be inserted
and mounted
into the openings, the heating so as to project into the the air passageway of
the housing
whereby the electric heating elements are in direct contact with air in the
air passageway. A
power source in communication with the heater assembly supplies the electric
heating elements
with power, for enabling the electric heating elements to heat the air in the
air passageway. An
air blower, for example, or other such device, could then direct the heated
air from the air
passageway to an area external to the heater assembly, such as a house or
other enclosed
structure, the air blower being supplied with power from the power source.
In an alternative embodiment, as shown in Figure 3, the pre-heater can further
comprise
a thermostatic control 53 in association with the electric heating elements 11
and the coolant in
the housing, wherein the thermostatic control is adapted to deactivate the
electric heating
elements 11 when a temperature of the engine coolant exceeds a pre-determined
level.
Preferably, the theimostatic control is positioned relative to the inlet of
the housing. Further, the
thermostatic control can also thus turn the electric heating elements 11 on
when a temperature
of the engine coolant falls below a pre-determined level.
The present invention has been described herein with regard to preferred
embodiments.
However, it will be obvious to persons skilled in the art that a number of
variations and
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modifications can be made without departing from the scope of the invention as
described
herein.
