U.S. patent number 3,841,236 [Application Number 05/344,747] was granted by the patent office on 1974-10-15 for contour underground mine car.
This patent grant is currently assigned to ACF Industries, Incorporated. Invention is credited to James C. Hammonds, Walter E. O'Leary.
United States Patent |
3,841,236 |
Hammonds , et al. |
October 15, 1974 |
**Please see images for:
( Certificate of Correction ) ** |
CONTOUR UNDERGROUND MINE CAR
Abstract
An underground mine car is disclosed in which the sides and
bottom members are at least partly curved preferably having a
radius of curvature from about 6 to about 60 feet for the sides and
10 to 30 feet for the bottom, enabling these members to resist
applied forces primarily in tension rather than in flexure
according to prior construction. In addition, the curved sides
transmit longitudinal loads, such as impact and squeeze, more
effectively than flat plate construction of equal cross-sectional
area. This enables thinner sections to be utilized, and a reduction
in car weight can be obtained. Since the number and extent of the
welds is marketly reduced in the construction of the invention, and
since such welds are often points of inception of corrosive attack,
the structure is less susceptible to corrosion and hence this
reduction in thickness and thus weight is permissible. The sides
and bottom can be made of substantially the same thickness and thus
can be made of a single member. Therefore only one longitudinal
joint along the bottom of the car is required resulting in
inexpensive fabrication. Only one top chord is required to
reinforce the unsupported edges of the curved side members. One or
a limited number of transversely extending reinforcing members may
be provided, if desired, particularly on long cars.
Inventors: |
Hammonds; James C. (St.
Charles, MO), O'Leary; Walter E. (Creve Coeur, MO) |
Assignee: |
ACF Industries, Incorporated
(New York, NY)
|
Family
ID: |
23351849 |
Appl.
No.: |
05/344,747 |
Filed: |
March 26, 1973 |
Current U.S.
Class: |
105/364; 105/161;
105/406.1; 105/396; 105/413 |
Current CPC
Class: |
B61D
11/02 (20130101) |
Current International
Class: |
B61D
11/02 (20060101); B61D 11/00 (20060101); B61d
011/02 () |
Field of
Search: |
;105/367,364,404,406,409,413,414,421,161,416 ;299/95 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Wood, Jr.; M. Henson
Assistant Examiner: Bertsch; Richard A.
Attorney, Agent or Firm: Cummings; Henry W.
Claims
What is claimed is:
1. An underground mine car comprising: opposite end sections
supported by railway car trucks, and a center section having a
bottom portion extending into the space between said trucks;
said center section comprising spaced apart integral center members
comprising an at least partly curved side portion having a radius
of curvature within the range of from about 6 to 60 feet and an at
least partly curved bottom portion having a radius of curvature
within the range of from about 10 to 30 feet; each of said spaced
integral center members having a bottom inward curve with a radius
of curvature of at least about three inches; said spaced integral
center members being joined together along their respective bottom
portions;
said opposite end portions comprising spaced apart integral end
members comprising an at least partly curved side portion having a
radius of curvature within the range of from about 6 to about 60
feet; and an at least partly curved bottom portion having a radius
of curvature within the range of from about 10 to 30 feet; each of
said spaced integral end members having a bottom inward curve
having a radius of curvature of at least about 3 inches; said
integral end members at each end being joined together along their
respective bottom portions;
at each end of the car a generally vertical end plate extending
transversely between said spaced apart integral end members; spaced
apart generally vertical joining plates joining the bottom portions
of said center section with the bottom portions of said end
sections, said joining plates extending transversely between said
spaced apart integral center members;
a chord extending longitudinally along each side of the car affixed
to said curved side portions on said integral central members and
to said curved side portions on said integral end members; whereby
lading loads applied to said center and/or end members are resisted
primarily in tension, and whereby the car volume to mine volume
ratio is maximized without overstressing the inward curve between
the side and bottom portion of said center and end members.
2. An underground mine car according to claim 1 wherein at least
one of said at least partly curved side portions in said center
section comprises a series of flat portions approximating a radius
of curvature within the ranges of from about 6 to 60 feet.
3. An underground mine car according to claim 1 wherein at least
one of said at least partly curved bottom portions in said center
section comprises a series of flat portions approximating a radius
of curvature of within the range of from about 10 to 30 feet.
4. An underground mine car according to claim 1 wherein at least
one of said at least partly curved side portions in at least one of
said end sections comprises a series of flat portions approximating
a radius of curvature of within the range of from about 6 to 60
feet.
5. An underground mine car according to claim 1 wherein at least
one of said at least partly curved bottom portions in at least one
of said end sections comprises a series of flat portions
approximating a radius of curvature of within the range of from
about 10 to 30 feet.
6. An underground mine car according to claim 1 wherein the spaced
integral members in said center section and in said end sections
are joined together by a generally longitudinally running weld.
7. An underground mine car according to claim 1 wherein said spaced
integral center members have a thickness not exceeding about 1/4
inch.
8. An underground mine car according to claim 7 wherein said spaced
integral end members have a thickness not exceeding about 1/4
inch.
9. An underground mine car according to claim 8 wherein the inward
curve at the bottom portion of said spaced integral center members
has a radius of curvature of at least from about 3 to about 10
inches.
10. An underground mine car according to claim 8 wherein said
spaced integral center members are welded to said spaced integral
end members.
11. An underground mine car according to claim 9 wherein the inward
curve at the bottom portion of said spaced integral end members has
a radius of curvature from about 3 to about 10 inches.
12. An underground mine car according to claim 11 wherein the side
portions of said spaced integral center members have a radius of
curvature from about 10 to 30 feet.
13. An underground mine car according to claim 12 wherein the side
portions of said spaced integral end members have a radius of
curvature from about 10 to 30 feet.
14. An underground mine car according to claim 11 wherein said car
has a height of from about 21/2 to 5 feet.
15. An underground mine car according to claim 14 wherein said car
has a width of less than about 8 feet.
16. An underground mine car according to claim 11 comprising a
channel member extending longitudinally between said joining
plates.
17. An underground mine car according to claim 16 wherein said
channel is affixed to the respective bottom members of said spaced
apart center members.
18. An underground mine car according to claim 17 wherein openings
are provided in the bottom portion of at least one of said center
members adjacent said joining plates.
19. An underground mine car according to claim 18 wherein
transverse plates are provided in said openings and affixed to at
least one of center bottom portions for engagement with unloading
lugs.
20. An underground mine car according to claim 11 wherein a
transversely extending chord is affixed to the upper portion of
each of said end plates and joins the longitudinally extending
chords on opposite sides of the car.
21. An underground mine car according to claim 20 wherein a curved
channel member extends transversely between, and is integral with
said spaced apart end members.
22. An underground mine car according to claim 21 wherein a stub
sill is affixed to said channel.
23. An underground mine car according to claim 22 wherein side
bearings are provided on said truck and on the bottom surface of
said end portions which engage each other at least during swaying
of the car about the truck.
24. An underground mine car according to claim 22 wherein said
truck is provided with side frames inboard of said side
bearings.
25. An underground mine car according to claim 11 wherein at least
one reinforcing member is provided extending in a transverse
direction affixed to at least one of said center and end
members.
26. An underground mine car according to claim 25 wherein said
reinforcing member joins the side portion of said center member
with the side portion of said end members.
27. An underground mine car according to claim 26 wherein at least
one reinforcing member extends transversely between said spaced
apart center members and is affixed thereto.
28. An underground mine car according to claim 26 wherein the
reinforcing members comprise gussets extending only part way into
the car.
29. An underground mine car comprising:
opposite end sections supported by railway car trucks and a center
section having a bottom portion extending into the space between
said truck;
said center section comprising spaced apart integral center members
comprising an at least partly curved side portion and an at least
partly curved bottom portion each having a radius of curvature
within the range of from about 10 to about 30 feet;
said integral center members having a bottom inward curve having a
radius of curvature within the range of from about 3 to 10 inches;
said spaced integral center members being joined together along
their respective bottom portions by a generally longitudinally
running weld;
said opposite end portions comprising spaced apart integral end
members comprising an at least partly curved side portion and an at
least partly curved bottom portion each having a radius of
curvature within the range of from about 10 to about 30 feet;
said integral end members having a bottom inward curve having a
radius of curvature within the range of from about 3 to 10
inches;
the integral end members located at each end of the car being
joined together along their respective bottom portions by a
generally longitudinally running weld; generally vertical end
plates at each end of the car extending transversely between the
spaced apart integral end members;
spaced apart generally vertical joining plates joining the bottom
portions of said center section with the bottom portions of said
end sections, said joining plates extending transversely between
said spaced apart integral center members;
a chord member extending longitudinally along each side of the car
affixed to said curved side portions on said integral center
members and to said curved side portions on said integral end
members;
whereby lading loads applied to said center and end members are
resisted primarily in tension, and whereby said center and end
members maximize the car volume to mine volume ratio without
overstressing the inward curve between the side and bottom portions
of said center and end members.
30. An underground mine car according to claim 29 wherein at least
one of said at least partly curved side portions in said center
section comprises a series of flat portions approximating a radius
of curvature of within the ranges of from about 10 to 30 feet.
31. An underground mine car according to claim 29 wherein at least
one of said at least partly curved bottom portions in said center
section comprises a series of flat portions approximating a radius
of curvature of within the range of from about 10 to 30 feet.
32. An underground mine car according to claim 29 wherein at least
one of said at least partly curved side portions in at leastone of
least one end sections comprises a series of flat portions
approximating a radius of curvature of within the range of from
about 10 to 30 feet.
33. An underground mine car according to claim 29 wherein at least
one of said at least partly curved bottom portions in at least one
of said end sections comprises a series of flat portions
approximating a radius of curvature of within the range of from
about 10 to 30 feet.
34. An underground mine car comprising:
opposite end sections supported by railway car trucks and a center
section having a bottom portion extending into the space between
said truck;
said center section comprising spaced apart integral center members
comprising an at least partly curved side portion and an at least
partly curved bottom portion each having a radius of curvature
within the range of from about 10 to about 30 feet; said integral
center members having a bottom inward curve having a radius of
curvature within the range of from about 3 to 10 inches; and a
thickness not greater than about 1/4 inch, said spaced integral
center members being joined together along their respective bottom
portions by a generally longitudinally running weld;
said opposite end portions comprising spaced apart integral end
members comprising an at least partly curved side portion and an at
least partly curved bottom portion each having a radius of
curvature within the range of from about 10 to about 30 feet; said
integral end members having a bottom inward curve having a radius
of curvature within the range of from about 3 to 10 inches and a
thickness not greater than about 1/4 inch, the integral end members
located at each end of the car being joined together along their
respective bottom portions by a generally longitudinally running
weld;
generally vertical end plates at each end of the car extending
transversely between the spaced apart integral end members; spaced
apart generally vertical joining plates joining the bottom portions
of said center section with the bottom portions of said end
sections, said joining plates extending transversely between said
spaced apart integral center members;
a chord member extending longitudinally along each side of the car
affixed to said curved side portions on said integral central
members and to said curved side portions on said integral end
members; whereby lading loads applied to said center and end
members are resisted primarily in tension, and whereby said center
and end members maximize the car volume to mine volume ratio
without overstressing the inward curve between the side and bottom
portions of said center and end members.
35. An underground mine car according to claim 24 wherein said side
frames have openings having springs therein for cushioning.
Description
BACKGROUND OF THE INVENTION
This invention relates to underground mine cars.
Dimensions are very restricted in underground mine cars,
particularly height and width. It is desired to utilize as much of
this mine tunnel cross section as possible for lading carrying
capacity.
Conventional underground mine cars usually include vertical
strengthening members along the longitudinal length on the sides of
the car. U.S. Pat. No. 2,859,709 directed to an ore mine car, and
U.S. Pat. No. 3,240,168 and Canadian Pat. No. 887,966 directed to
railroad gondola cars are illustrative of this general type of
construction. See also Railway Locomotives and Cars, Nov. 1969,
pages 26 and 27.
Cost is a very important factor in the marketability of the car.
One of the main factors affecting the cost of the car is the weight
or amount of metal in the car. The vertical strengthening members
in the above constructions increase the weight and hence the cost
of the car. The strengthening members also increase the expense of
manufacture in requiring numerous fittings and weldings.
Furthermore, the weld joints are often a point of inception of
corrosive attack.
One current commercial railroad car construction described and
illustrated in Railway Locomotive and Cars, Jan. 1972, pages 23 and
24, is used in hauling coal but not as an underground mine car. The
car has a curved bottom having a small radius and sides which are
partially curved. The curved portions take lading stress in
tension. The structure basically includes three members, a bottom
member with a small radius welded to two side members which are
curved with a large radius at the bottom and flat near the top.
Longitudinal chord members are provided along the sides of the car
and at the top.
However, this car requires two longitudinally running welds in the
center portion, which is expensive. Furthermore, this car is not
efficient in maximizing volumetric capacity due to the sharp
curvature of the bottom portion of the car and providing two
longitudinal chord members on each side of the car adds to the
weight of the car and to fabrication expense.
One object of the present invention is to provide an underground
mine car of reduced weight without significantly sacrificing
strength, rigidity or wear resistance of the car.
It is another object of the present invention to provide a car
which efficiently utilizes the space available in a mine tunnel as
lading carrying volume of the car.
Another object of the present invention is to provide an
underground mine car which is easily and inexpensively
fabricated.
Another object is to provide an underground mine car which is
resistant to corrosive attack.
Another object of the present invention is to provide an
underground mine car which is readily drainable.
Other objects will be apparent from the following description and
drawings.
THE DRAWINGS
FIG. 1 is a perspective view of the underground mine car of the
present invention;
FIG. 2 is a top view of the underground mine car of the present
invention;
FIG. 3 is a side elevational view of the underground mine car
according to the present invention;
FIG. 4 is a sectional view of the underground mine car according to
the present invention along the line 4--4 in FIG. 2;
FIG. 5 is a sectional view of the underground mine car of the
present invention along the line 5--5 of FIG. 2;
FIG. 6 is a sectional view of the end portion of the underground
mine car along the line 6--6 in FIG. 2;
FIG. 7 is a sectional view of the underground mine car of the
present invention along the line 7--7 in FIG. 2;
FIG. 8 is an enlarged sectional view showing one type of
longitudinal weld which may be used for the joint along the bottom
of the car.
SUMMARY OF THE INVENTION
In accordance with the present invention an underground mine car is
provided in which the sides and bottom members are at least partly
curved enabling these members to resist applied lading forces
primarily in tension rather than flexure according to prior
construction. In addition, the curved sides transmit longitudinal
loads (i.e. impact) more effectively than flat plate construction
of equal cross-sectional area. The radius of curvature is
preferably from about 6 to 60 feet for the sides and 10 to 30 feet
for the bottom. This enables thinner sections to be utilized, and a
reduction in car weight can be obtained. Since the number and
extent of the welds is marketly reduced in the construction of the
invention, and since such welds are often points of inception of
corrosive attack, the structure is less susceptible to corrosion
and hence this reduction in thickness and thus weight is
permissible. Preferably the sides and bottom are made of
substantially the same thickness and thus can be made of a single
member. Therefore only one longitudinal weld of other appropriate
joining means along the bottom of the car is required, resulting in
inexpensive fabrication. Preferably only one chord is used as a
longitudinal reinforcement for the sides of the car. One or a
limited number of transversely extending reinforcing members may be
provided, if desired, particularly on long cars.
DETAILED DESCRIPTION
The underground mine car of the present invention is indicated
generally at 10 in the drawing. The center portion 11 comprises
spaced apart integral side and bottom members 12 and 14 which, if
desired, may be made of a single piece of metal. The integral
members 12 and 14 respectively comprise at least partly curved side
portions 17, 19 and at least partly curved bottom portions 16 and
18. The general shape is shown in FIG. 4.
The radius of curvature of the side and bottom portions is a
balance between curvature to increase strength and rectangularly to
maximize mine tunnel cross section. The radius of curvature for the
sides is preferably not more than about 60 feet depending upon car
length to provide for strength and not less than about 6 feet to
avoid excessive loss of lading capacity. At radii above about 60
feet the curvature of the sides approach a flat plate, requiring
reinforcement on the side and bottom. At a radius less than about 6
feet loss of carrying capacity occurs at a greater rate than
savings in weight and car cost. Limited portions of the side and/or
bottom may have little curvature or be substantially flat,
generally not exceeding about 25 percent of the side and/or bottom.
If desired, a series of flat portions may be utilized which
approximate a radius within the above range. Preferably the radius
of curvature for the bottom is from acout 10 to about 30 feet to
maximize both strength and carrying capacity.
The radius of curvature for the inward curve at the bottom is
dictated primarily by that radius which is large enough to avoid
excessive strain which may result in cracking. To this end the
radius is preferably not less than about 3 inches. It is desirable
to have the radius as small as possible preferably not above 10
inches to maximize lading capacity.
Bottom portions 16, 18 may have the same or a different radius of
curvature than the side portions. Preferably, however, the radius
of curvature of the side and bottom portions is substantially the
same. For example, the side and bottom may be rolled to a desired
radius of curvature and then bent to form the inward curve defining
portions 16 and 18.
The height of the car is dictated by the height of the mine tunnel
and may be as low as about 30 inches or as high as 5 feet or
higher. The width of the car again is dictated by the width of the
tunnel and, for example, may be from 6 feet to 8 feet.
Members 12 and 14 are welded or otherwise appropriately affixed
together, such as by riveting, bolting, adhesive bonding, or a
combination thereof, as indicated generally at 20 along the bottom
portion of the car. For example, weld 20 may comprise, for example,
a weld in which the members 12 and 14 are brought into close
contact, for example, 0 to 1/8 inch and a weld support strip 22
tack welded to the two members along the length of the car body.
Then the strip 22 is welded to respective bottom portions 16 and 18
of the members 12 and 14 as shown in FIG. 8.
Drain holes 106 are preferably provided in bottom portions 16 and
18. The curved sides 17 and 19 and curved bottom thus provide
positive drainage.
The bottom portion of the car further comprises a channel 24 welded
to the respective bottom portions 16 and 18 along the car and
terminating adjacent vertical plates 26 and 28. Channel 24 provides
longitudinal floor reinforcement. Openings 27 and 29 are cut in the
bottom portions 16 and 18 and lug plates 30 and 32 are also
provided therein adjacent plates 26 and 28, for example by welding.
As shown in FIG. 3, the lug plates are provided so that lugs 34
mounted upon a conveyor 36 are movable about wheels 38 and 40 by an
appropriate power source (not shown) and a cam surface 42 is
provided to move lugs 34 into the locking position in engagement
with the lug plates to engage the bottom of the cars and move them
forward along the track to position them for dumping. The conveyor
36 and lugs 34 are shown schematically as their use and function
are well known in the art.
End portions 46 and 48 are constructed similarly to the center
portion of the car. Each integral members 47 and 49, if desired,
may be made of a single piece of metal and comprise respectively
the side portions 50 and 52, at least partly curved, and bottom
portions 54 and 56, also at least partly curved. Similar ranges of
radii of curvature may be used for the side and bottom curvature
and for the bottom inward curve as are used in the center portion.
The main difference is that the vertical extent of the side
portions is considerably foreshortened. Integral members 47 and 49
are welded together at 58 with a weld similar to that shown in FIG.
8. Integral members 47 and 49 are preferably formed separately and
butt welded to center members 12 and 14.
End portions 46 and 48 are mounted upon suitable trucks 60 and 62
comprising wheels 64, 66, side bearings 68, 70, and springs 72, 74
(shown schematically in FIG. 5). Center plates 76 and 78 are
mounted below stub sills 75 and 77. Transversely extending body
bolsters 80 and 82 (FIGS. 2 and 5) which extend below bottom
portions 54 and 56 and are affixed to side portions 50 and 52 to
transmit lading loads from the side members to the trucks 60-62.
Each end portion is provided with a body side bearing 84, 86 which
may comprise, for example, angles 88, 90 having mounted thereon
steel plates 92 and 94.
End plates 96 and 98 are welded to integral members 47 and 49, both
to the bottom portions 54 and 56 and to side portions 50, 52.
Mounted upon the end plates 96 and 98 respectively are chords 100,
102 of a channel section as shown in FIG. 6 comprising channel
member 104. Along the sides of the car members 13 and 15 which may,
for example, have a cross section as shown in FIG. 7, are provided
which extend through the end portions 46 and 48 as indicated at 51
and 53. End portions 51 and 53 are preferably welded to chords 100
and 102.
Gussets 108 and 110 preferably are also provided and are welded in
place to the car sides and to plates 26 and 28 respectively. The
gussets help to maintain the curvature in the preformed shape.
Additionally, if desired, one or a limited number of transverse
plates 112 may be provided to support integral members 12 and 14
and maintain rigidity. The plates 112 are welded to members 12, 14
and optionally to channel 24. In general, if used at all, one or at
most two or three such members would be provided. It is desirable
to minimize the number of such transverse members to minimize
weight, fabrication time, and avoid weld joints where corrosion may
begin.
Strength and rigidity is obtained through the use of the curved
sides and curved bottom. The chords along the side and end portions
of the car provide additional strength and rigidity. Thus, less
weight per unit strength is obtainable with the construction of the
present invention.
Through the use of the curved sides and bottom the longitudinal
forces (impacts) on the car are more effectively taken and a
thickness reduction from the usual 5/16 inch or greater to below
1/4 inch, preferably about 7/32 inch, can be realized without the
loss of strength and rigidity. For example, a thickness reduction
of 10 to 40 percent can often be obtained, which results roughly in
a corresponding weight reduction in the car body, excluding trucks
and draft gear.
The radius of curvature of the center and side portions and the
inward curve at the bottom are such that the car volume to mine
volume ratio is maximized and only about 10 percent of available
mine volume is lost due to the curved sides corresponding to
approximately 6 feet radius. Most preferably not more than about 5
percent is lost corresponding to approximately 14 radius.
Furthermore, the simplified design with a single longitudinal weld
reduces fabrication time and thus reduces labor cost.
The underground mine car is preferably made of corrosion resistant
steel, for example of COR-TEN.sup.(R), a registered trademark of
U.S. Steel Corp., having a composition of C 0.12 max, Mn 0.20-0.50,
P 0.07-0.15, Si 0.25-0.75, Cu 0.25-0.55, Cr 0.30-1.25, S 0.05 max,
Ni 0.65 max.
Through the use of an appropriate corrosion resistant, low cost
steel, little or no loss of corrosion and wear resistance results
from the design of the present invention. In fact, fewer welded
joints avoid points for the conception of corrosive attack, thus
improved corrosion resistance may be observed with the design of
the present invention.
* * * * *