U.S. patent number 3,621,907 [Application Number 05/033,319] was granted by the patent office on 1971-11-23 for cooling system for locomotive engines and the like.
This patent grant is currently assigned to General Motors Corporation. Invention is credited to Max Ephraim, Jr., Ludvik F. Koci, Humberto Suarez.
United States Patent |
3,621,907 |
Ephraim, Jr. , et
al. |
November 23, 1971 |
COOLING SYSTEM FOR LOCOMOTIVE ENGINES AND THE LIKE
Abstract
A locomotive cooling system has radiators mounted above the
normal coolant level during engine shutdown in the engine and water
tank so as to drain the radiators when the engine stops, to avoid
the possibility of freezing the water therein. An automatic
pressure relief and overflow valve is provided which is open during
engine shutdown to drain excess water from the cooling system so as
to prevent the retaining of any coolant in the radiators. When the
engine is operating, the valve is normally closed by engine
lubricating oil pressure to permit normal pressure buildup in the
engine cooling system. However, the valve opens to relieve excess
pressure in the cooling system. Manual opening means are also
provided to relieve system pressure during engine operation.
Inventors: |
Ephraim, Jr.; Max (Evergreen
Park, IL), Koci; Ludvik F. (La Grange Park, IL), Suarez;
Humberto (Forest Park, IL) |
Assignee: |
General Motors Corporation
(Detroit, MI)
|
Family
ID: |
21869728 |
Appl.
No.: |
05/033,319 |
Filed: |
April 30, 1970 |
Current U.S.
Class: |
165/51;
123/41.08; 123/41.14; 165/71; 165/104.31; 165/104.32; 251/14;
251/77; 137/87.03 |
Current CPC
Class: |
F01P
11/20 (20130101); Y10T 137/2703 (20150401) |
Current International
Class: |
F01P
11/14 (20060101); F01P 11/20 (20060101); F01p
011/02 () |
Field of
Search: |
;165/71,107,51
;123/41.14,41.08,41.54 ;105/62A ;180/54A ;137/87
;251/14,63.4,77 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Davis, Jr.; Albert W.
Claims
We claim:
1. An engine cooling system for a locomotive or the like, said
cooling system comprising means defining coolant passages in such
engine and a circulating pump having an outlet connected to supply
coolant to said passages,
a radiator mounted at a high point in the cooling system, said
radiator being connected between the outlet of said engine coolant
passages and the inlet of said circulating pump to complete a
closed circulation system,
a water tank mounted at a lower level than said radiator but above
the inlet to said circulating pump, said tank being connected to
said pump inlet and being adapted to maintain a head of water
coolant at said pump inlet, and
a drain valve connecting with an upper portion of said water tank,
said valve including means responsive to a predetermined condition
of engine operation to close the valve during engine operation so
as to permit the cooling system to be pressurized and to open the
valve when the engine is stopped to drain excess water in the
system so as to maintain during engine shutdown, a water level
below the radiators to prevent any possibility of the radiators
being damaged due to freezing.
2. The cooling system of claim 1 wherein said drain valve is
additionally responsive to pressure in the cooling system so as to
open to relieve any excessive pressure buildup in said system.
3. The combination of claim 2 wherein said drain valve further
includes manual actuating means to permit said valve to be manually
opened during engine operation so as to relieve the system
pressure.
4. An engine cooling system having a coolant supply tank and a
drain valve connecting with an upper portion of said tank, said
drain valve being responsive to a predetermined condition of engine
operation to close during engine operation so as to permit the
cooling system to become pressurized and to open when the engine is
stopped to drain excess coolant from the system so as to maintain a
predetermined maximum water level during engine shutdown.
5. The cooling system of claim 4 wherein said drain valve is
connected to the engine lubricating oil system and is closed by the
buildup of pressure in said oil system during engine operation.
6. In a pressurized cooling water system of a diesel engine, the
combination with a storage tank and a radiator exposed to ambient
air and connected to and positioned above the level of the tank for
gravity draining thereinto when the engine is stopped, of a drain
port in a side of the tank at a level at which the tank therebelow
during running of the engine has sufficient excess water capacity
to contain the then water content of the radiator, and an automatic
dump valve connected to said dump port for automatically opening
said port for and closing said port against dumping respectively on
stopping and running of said engine.
Description
FIELD OF THE INVENTION
This invention relates to engine cooling systems for locomotives
and the like and, more particularly, to an improved cooling system
having automatic pressure relief and shutdown level control
features.
DESCRIPTION OF THE PRIOR ART
It is known in the art relating to diesel locomotives, power units
and other mechanisms utilizing internal combustion engines for
exterior use, to provide a water cooling system having radiators
mounted above the normal water level in the system when the engine
is shut down. This permits the water coolant to drain from the
radiators during engine shutdown to avoid the possibility of
coolant freezing in the radiator elements, which are generally
mounted in a position exposed to air at ambient temperatures.
In such systems, it is normally possible to add cooling water to
the tank while the engine is operating, at which time the level in
the water tank is lower than when the engine is stopped and the
cooling system may, therefore, be inadvertently overfilled. Then
when the engine is stopped the water level may be sufficiently high
to retain some coolant in the radiators with consequent danger of
freezing in cold weather. The problem has been complicated by the
recent use of pressure cooling systems, which require relief of the
system pressure in order to drain excessive water from the system
or to add water or cooling water treatment to the water tank.
SUMMARY OF THE INVENTION
The present invention provides an improved engine cooling system of
the above-described type which incorporates an automatic valve
having several functions. (1) It opens to relieve excessive
pressure in the cooling system. (2) It is normally closed when the
engine is running so as to permit normal pressure buildup in the
cooling system but it opens when the engine is stopped so as to
drain any excess water from the cooling system and thus provide for
positive draining of the radiators. (3) It provides for manual
pressure relief so as to permit safe removal of the water tank
filler cap for filling of the water tank or the addition of water
treatment.
Further details and advantages of the cooling system and valve
arrangement will be apparent from the following description of a
preferred embodiment taken together with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a side view representing, in part diagrammatically, a
locomotive engine with attached cooling and lubricating oil system
elements;
FIG. 2 is an enlarged view of a portion of FIG. 1 taken generally
in the plane indicated by the line 2--2 as viewed in the direction
of the arrows; and
FIG. 3 is a cross-sectional view showing the interior construction
of the valve as viewed in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the drawings, numeral 10 generally indicates the car body of a
locomotive in which there is mounted a diesel engine 12 having
externally connected radiators 14 (shown diagrammatically) and
various lubricating and cooling system elements mounted in a
separate plumbing rack 16.
Engine 12 is of a type in current use for diesel locomotives and
includes a pair of water pumps 18 (only one being shown) which have
outlets connecting with the internal cooling passages (not shown)
of the engine. The engine also has a lubricating oil pump 20 which
supplies pressure to the engine lubricating oil system whenever the
engine is running. A pressure line 22 connects a distant portion of
the lubricating oil system with the engine governor 24 to provide a
pressure signal indicating proper operation of the engine.
The engine cooling system passages have an outlet which connects
through conduit 26 with the radiators 14. The radiators are, in
turn, connected through conduits 28 with an oil cooler 30 mounted
in the plumbing rack 16. Oil cooler 30 then connects through dual
conduits 32 with the inlets of the water pumps, completing the main
cooling water flow circuit.
A water tank 34 is also mounted in plumbing rack 16 below the level
of the radiators and is connected through vertical conduits 36,
which extend from the lower surface of the tank to the conduits 32
which convey water to the water pump inlets. The water tank is
adapted to retain a supply of water and to provide a pressure head
on the pump inlets so that water is provided to the pump inlets
under all operating conditions.
When the engine is stopped, the cooling water level in the engine
cooling system normally extends along a plane 38 slightly below the
top of the water tank 34 so that no water remains in the radiators
14. When the engine is running the water level in tank 34 drops,
since the engine water pumps maintain a solid flow of water through
the main coolant circuit and the water to fill the radiators is
supplied by the water tank.
Water tank 34 is provided with an overflow pipe 40 which extends
inwardly to the normal shutdown water level and connects outwardly
through an elbow 42 with an automatic pressure relief and level
control valve 44. Valve 44 is, in turn, connected with a water
drain line 46 and, through oil lines 48 and 50, with the oil
pressure line 22.
Valve 44 comprises a housing having a valve seat 52 which is
engageable by a reciprocable valve element 54 to close the drain
passage from the tank. Element 54 is supported by a movable guide
member 56, which carries a spring 58. The spring acts against the
guide member and a spring seat 60 so as to bias the valve element
54 toward the valve seat 52. Travel of the spring 58 is limited
when the valve is open by a cap member 62 that is attached to the
guide member 56.
A hydraulic piston 64 acting within a cylinder 66 at one end of the
valve member connects with guide member 56 and is acted upon by a
second spring 68 which urges the piston in a direction to open
valve element 54 by moving the guide member, cap and valve element
assembly 56, 62, 54. Provision is made for the introduction of
lubricating oil pressure from oil line 50 through an elbow 70 and
orifice 72 to the interior of cylinder 66 so as to act against the
piston 64. Thus, when the engine is running, the oil pressure
forces piston 64 in a valve closing direction so as to compress the
spring 68 and permit the valve element 54 to be closed by spring
58.
The valve 44 also includes a manual operating handle 74 connected
with a pivotable fork 76. The fork is engageable with a flange 78
of the valve element 54 so that rotation of the handle 74 (in a
clockwise direction as shown in FIGS. 1 and 2) is effective to
manually open the valve by moving element 54 in a valve-opening
direction.
The operation of the above described cooling arrangement is as
follows. When the engine is stopped, water and water treatment may
be added to the cooling system through a suitable opening (not
shown) in the top of the water tank which is normally sealed by a
suitable closure. When the proper coolant level is reached, the
excess coolant flows into pipe 40 and down through the open valve
44, passing out through drain pipe 46. Since there is no pressure
in the engine lubricating oil system at this time, spring 68 holds
piston 64 in a leftward position, as shown in FIG. 3, thereby
moving the guide member and valve assembly leftwardly so that the
valve is open.
When the engine is started, the lubricating oil pressure is
transmitted through pressure lines 22, 48 and 50 to the cylinder 66
in the valve body. There the oil pressure forces piston 64 to the
right, permitting spring 58 to seat the valve element 54. At the
same time, the engine water pumps draw water from the water tank 34
and force it through the engine and into the radiators 14 from
whence it passes through the oil cooler and around to the inlet of
the water pumps in a continuous circuit. As previously mentioned,
the level in the water tank drops during engine operation due to
the water taken from it, which is then flowing through the
radiators and other parts of the cooling system.
Operation of the engine increases the temperature of the coolant
and, since the valve 44 is closed, pressure is developed in the
cooling system, which permits operation of the system at high
temperatures without boiling. If an excessive pressure is reached,
the coolant pressure acting directly on valve member 54, moves the
valve member leftwardly against the bias of spring 58, opening the
valve and relieving the pressure. In this way, valve 44 acts as a
pressure relief valve.
If, during engine operation, it is desired to add additional
cooling water or cooling water treatment to the cooling system, it
is necessary first to relieve the pressure in the system in order
to permit the filler cap closure to be safely opened. Such pressure
relief may be manually accomplished by rotating the valve operating
handle 74 clockwise, as shown in FIGS. 2 and 3, so that the fork
member 76 engages flange 78 of the valve member, moving the valve
member in an opening direction and relieving the cooling system
pressure.
While the invention has been described by reference to a preferred
embodiment selected for purposes of illustration, it should be
obvious that numerous modifications of the inventive concepts
disclosed could be made within the spirit and scope of the
disclosure. Accordingly, the invention is intended to be limited
only by the language of the following claims.
* * * * *