Note: Descriptions are shown in the official language in which they were submitted.
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RAIL GRINDING APPARATUS
BACKGROUND OF THE INVENTION
This invention relates to a rail grinding
apparatus for grinding the welded joints of railroad
rails. More particularly, it relates to a rail grinding
apparatus which does not require the exertion of any
significant force by the operator of the apparatus.
The present invention will be described, in
relation to the prior art, with reference to the
accompanying drawings, in which:
Figure 1 is an elevation of a pair of railroad
rails which have been connected by butt welding;
Figure 2 is a cross-sectional view taken along
Line II-II of Figure l;
Figure 3 is a perspective view of an embodiment
of a rail grinding apparatus according to the present
invention when grinding the top surface of a rail;
Figure 4 is an end view of the rail grinding
2~ apparatus of Figure 3 when grinding the gage corner
surface of a rail; and
Figure 5 is an end view of the rail grinding
apparatus of Figure 3 when grinding the upper lateral
surface of a rail~
The rails of modern railroads are usually
connected with one another by butt welding. Various butt
welding methods are employed, including gas pressure
welding, flash butt welding, thermit welding, and
enclosed arc welding. Figure 1 is a side view of two
rails 1 which have been connected by conventional butt
welding, and Figure 2 is a cross-sectional view taken
along Line II-II of Figure 1. As shown in these figures,
a weld bead is formed around the entire periphery of the
joint between the two rails 1. The weld bead extends
considerably above the surface of the rails 1, so it must
be removed by grinding. Conventionally, the weld bead is
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removed from the weld ~oint using a hand grinder. A
surface hand grinder is used to grind the top surface 12,
while common hand grinders are used to grind the gage
corner sur$aces 13 and the upper lateral surfaces 14 of
the rails l. Two different types of grinders must be
used. These grinders are hereunder collectively referred
to merely as "hand grinders'`.
Furthermore, the contact force between a hand
grinder and the surface of the rails l must bè exerted by
the operator of
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the hand grinder~ AS it iS difficult for an operator to exert
a steady contact force, hand ~rinding often produce~
irregularities in the surface of the rails 1, and it is
difficult to obtain a finished surface having the required
surEace tolerance of -0.1 - +0.~ mm/m. Hand grinding also
produces an unpleasant shrill noise, which is objectionable
from the standpoint of both the operator of the hand grinder
and others working nearby. ~urthermore, a hand grinder
generates vibrations which are not only fatiguing to an
1~ operator and prevent him from working for long periods but
whicll al~o ~nay cause the operator to develop medical problems,
such as Raynaud's phenomenon.
SUMMARY OF THE INV13NTION
lS Accordingly, it is an object of the present invention to
provide a rail grinding apparatus for railroads ralls which
can grind the surface of a rail without an operator having to
exert any significant force.
It is another object of the present invention to provide
~ rail grinding apparatus whicb can provide a uniform finished
~urface.
It is yet anotber object of the present in~ention to
provide a rail grinding apparatus which produces little noise.
It is a further object of the present invention to
provide a rail ~rinding apparatus which imparts little
vibration to the hands of an operator.
A rail grinding apparatus according to the present
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invention has a frame equipped with rolling support
members, such as rollers or wheels, which support the
frame while rolling along the surface of a rail. A
rotary grinding device, such as a motor-driven grinding
belt or a grinding wheel, is mounted on the frame such
that the grinding device can grind the surface of a rail
when the rolling support members are resting on the rail.
The rolling support member carry all or substantlally all
of the weight of the grinding apparatus, and the force of
contact between the grinding device and the rail is
produced by the weight of the grinding apparatus. The
grinding apparatus can be rolled along a rail by being
lightly pushed by an operator, and the operator does not
have to exert any signi~icant force on the grinding
apparatus during operation. The grinding device may be
surrounded by a guard which protects the operator and
reduces the level of noise generated by the grinding
apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred embodiment of a rail grinding
apparatus according to the present invention will now be
described while referring to the accompanying drawings.
Figure 3 illustrates this embodiment when grinding the
top surface 12 of a rail 1. The rail grinding apparatus,
~5 which is indicated by reference number 2, has a support
frame 3 which may have a number of openings formed
therein to enable it to be easily grasped by an operator.
Rotating support members in the form of first and second
rollers 41 and 42 are rotatably mounted on the lower
portions of the front end ~the left end in Figure 3) and
the rear end of the frame 3. The first rollers 41 extend
perpendicularly from the frame 3, while the second
rollers 42 extend downwards in the plane of the frame 3.
As shown in Figure 3, when grinding the top surface 12 of
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a rail 1, the first rollers 41 sit on the surface 12 of
the rail 1 and support the weight of the grinding
apparatus 2, while the second rollers 42 contact the
upper lateral surfaces 14 of the rail 1. The front end
S of the frame 3 includes an adjusting screw 31 which
enables the height of the front end to be adjusted.
A rotary grinding device in the form of a
grinding belt 23 is wrapped around a pair of pulleys 21
and 22 whiCh are
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rotatably mountecl on the frame 3. The pulley~ 21 and 22
extend p~rpendicularly from the frame 3 parall~l to the fir~t
roller~ 41. The front pulley 22 i~ preferably mad~ of an
elastic material ~uch a~ rubber so that the gr~nding belt 23
will be re~illiently presqed agai4st the rail 1 by the pulley
22. The rear pulley 21 is rotated by an electric motor 24
which is moun~ed on the frame 3, and tbe ro~ation of th~ rear
pulley 21 is transmitted to the front pulley 22 by the
grinding belt 23. The tension in the grinding belt 23 can be
adjusted by a conventional tensioning mechanism 25 which i~
secured to the frame 3. The motor 24 can be controlled by a
switch box 7 which is incorporated into the upper portion of
the frame 3.
The pulleys 21 and 22 and the grinding belt 23 are
covered by a protective cover 5 which prevent~ clothing and
other items from ~ecoming caught in the pulleys 21 and 22 and
alQo protects the operator from grinding spark8. The cov~r 5
can ~lso greatly reduce the lev~l of noiQe wh$ch ~8 generated
by th~ grinding appàratus. A guard plate 6 i8 secured to the
under~ido of ~he protective cove~ 5 ~U9t to the rear of the
rear puliey 21 to protect the rear rollors 41 and 42 from
grinding sparks.
~ he force of contact between the grinding belt 23 and the
rail 1 can be ad~usted by the ad~usting screw 31. A~ thi~
force is provided by the weight of the grinding apparatu8 2,
which is constant, grinding ~an be perform~d with a uniform
grinding force, so a uni,form surf~ce fini~h can be obtained.
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When grinding the top surface 12 of a rall 1, the
operator rolls the grinding apparatus 2 along the rail 1 to a
Welded joint. When rolling the grinding apparatu~ 2 from
joint to joint, it may be desirable to ad~ust the ad~ustlng
screw 31 so that the grinding belt 23 is completely separated
from the surface of the rail 1 to reduce frictional
resistance. When the weld joint to be -Qu~iected to grinding
is reached, the adjusting screw 31 i9 adjusted to produce a
suitable contact force between the grinding belt 23 and the
rail 1. The operator then turns on the motor 24 to rota~e the
grinding belt 23. While ~he grinding belt 23 ls turning, the
operator may want to move the frame 3 in the len~thwise
direction of the rail 1 back and forth over the joint. When
the first rollers ~1 are rolling on the top surface 12 of a
rail 1, the second rollers 42 act as guide rollers and help
the operator to keep the grinding apparatus 2 atop the rail 1.
As the weight of the grlnding apparatus 2 i8 entirely
supported by tbe fir~t rolters 41 and the grinding force is
provided by the weight of the grinding apparatus 2, tbe
operator has to exert very little force on the grinding
apparatus 2 and is not subjected to harmful vibrations.
When grinding the gage corner surfaces 13 o~ a rail 1,
the frame 3 is tilted a~ shown in Figure 4 ~o that the first
and second rollers 41 and 42 rest on the qage corner sur~ace9
13 on opposite sides of the rail 1. In this attitude, the
motor 24 is turned on to grind the gage corner Qurfaco 13 on
which the first roller 4t is resting:- When it is desired to
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grind the gage corner surface 13 on the other ~ide of the rall
1, the grinding apparatus 2 is repositioned ~o that the first
rollers 41 rest on the other side.
When grinding the upper lateral surface 14 of a rail, the
frame 3 is tilted un~ iS horizontal as shown in Figure 5.
Tn this state, the first rollers ~1 contact the upper lateral
surface 14 which is to ~e subiect~d to grinding, and the
~econd rollers ~2 rest on the top surface 12 of the rail.
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