Note: Descriptions are shown in the official language in which they were submitted.
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BELT GRINDER
The invention concerns a belt grinder according to the
preamble of claim 1.
Belt grinders of the aforementioned kind are well
known, for example from CH-PS 668 212. Such belt grinders are
relatively complicated and accordingly their provision is very
expensive, since they require special carriers as well as guide
devices associated with the carriers, in order to guide the
contact roll in keeping with the profile of the surface to be
ground.
The object of the invention is to provide a belt
grinder of the mentioned type which has a simple construction and
which in a simple way adapts to the contour of the surface to be
ground.
This object is inventively solved in the invention by
the characterizing features of claim 1. The floating support for
the contact roll makes possible its adaption to the contour of
the surface to be ground, as for example the surface of a
cambered roll, the inner and outer surfaces of containers, and
the like, whereby the guide apparatus can be simplified and while
yet achieving a high accuracy and surface finish quality.
Advantageous developments of the belt grinder are
descrihed in claims 2 to 7. For the implementation of the
floating support for the contact roll for the grinding belt
diverse possibilities arise. An especially advantageous
implementation is described in claim 2. The grinding accuracy
can be improved by a further development according to claim 3,
since then the pressure of the contact roll at all angular
positions of the contact roll remains constant. Especially
advantageous is a further development according to claim 4, which
makes possible an automatic finely regulatable delivery of the
belt grinder mechanism. For the tensioning of the grinding belt
different implementation possibilities arise such as tensioning
rolls and alike. Especially advantageous and simple is a
development according to claim 5, whereby a symmetrical
construction of the belt grinder mechanism is promoted. In it
the belt tensioning apparatus in the simplest case can be made as
a mechanical spring apparatus.
An especially advantageous implementation of the belt
grinder is described in claim 6 which makes possible a delicate
control of the grinder so that, for example, rolls with non-
cylindrical surfaces over their entire lengths can be ground with
an application pressure that remains constant. It involves a
belt grinder that can be adjusted to the different grinding
requirements so that a grinding with highest accuracy is
possible.
Especially practical is the implementation of the
grinder according to claim 7 which hinders the tilted application
of the contact roll to the work roll and with it the production
of fault type grinding marks.
Embodiments of the subject matt~r of the invention
hereafter described in more detail in connection with schematic
drawin~s which show:
Fig. 1 is a side view, in the direction of sliding
movement, of a belt grinder applied to a work roll.
Fig. 2 is a top view of the belt grinder of Fig. 1.
Fig. 3 is a sectional view of the frame of the belt
grinder taken along the line III-III of Fig. 4.
Fig. 4 is a sectional view of the frame of the belt
grinder taken along the line IV-IV of Fig. 3.
Fig. 5 is a sectional view of the frame of the belt
grinder with a supplemental securing apparatus taken along the
line V-V of Fig. 6.
Fig. 6 is a right side view of the securing apparatus
of Fig. 5.
Fig. 7 is a horizontal sectional view of the belt
grinder of Fig. 1.
Figs. 1 and 2 are complete views of a belt grinder
which is arranged on the scraper apparatus 2 of a roll 4, for
example the roll of a paper machine. The belt grinder includes a
frame 6 with rollers 8 which is placed on a scraper 10 of the
scraping apparatus 2, the scraping apparatus 2 being shown in the
condition of being pi~oted away from the roll 4. A frame 6
includes a holder 12 with an engagement roller 14, which
laterally engages the carrier 16 of the scraping apparatus 2.
The actual belt grinder mechanism 18 is fastened to the frame 6.
The holder 12 has an upper arm 20 and a lower arm 22
which are fastened to the frame 6 and extend transversely to the
plane of the rollers 8. Each arm 20, 22 is provided with a
double clamping member 24 which itself is fixed to the associated
arm 20, 22 by means of a clamping screw 26. A rod 28 is fixed to
the clamping members so as to extend transversely to the arms and
likewise is fixed by clamping screws 30. The engagement roller
14 is supported on the lower end of the rod with the plane of the
roller 14 running perpendicular to the plane of the rollers 8.
With the help of the clamping members 24 the rod 28 can be
adjusted as to its position on the arms 20, 22 as well as to its
height. The arrangement of the holder 12 is such that the rod 28
is located along the length of the frame 6 halfway between the
rollers 8. Thereby a three point support is achieved which is
especially stable. Moreover this support makes it possible that
the belt grinder mechanism 18 can be exchangably fastened at the
cheeks 32, 34 of the frame 6. For this the belt grinder
mechanism 18 is made so as to be essentially mirror image
symmetrical with respect to the horizontal plane 36, so that
through use of the mounting plate 38 forming part of the grinder
mechanism the grinder mechanism can be selectively attached to
either one of the two cheeks 32, 34.
Figs. 3 and 4 show details of the drive of the rollers
8 of the frame 6. As to this, the frame contains a drive motor
40 which through a drive 42 and a clutch 44 drives a drive wheel
46 for a toothed belt 48. The belt 48 is trained over two wheels
50, fastened to shafts 52, on which the rollers 8 are arranged.
~ 'igs. 5 and 6 show a supplementary securing mechanism
54 for securing the belt grinder to the scraper apparatus 2. In
this case the scraper 10 of the scraper apparatus 2 is first
replaced in the scraper apparatus 2 by an L shaped rail 56. The
rollers 8 run on the rail 56. The securing mechanism 54 includes
securing rollers 58 which are associated with the rollers 8 and
which are pivotal into engagement with the inner side 60 of the L
shaped rail 56. For this the securing rollers 58 are fastened to
a pivot axle 62 which in turn is pivotably supported in arms 64
on the frame 6. To the pivot axle 62 is fastened a lever 66
which is connected through a coupling member 68 with a threaded
¦spindle 70. The spindle 70 cooperates with a rotatably supported
¦sleeve 72 having a non-illustrated internal thread. The sleeve
172, which is rotatably supported in the frame 6, is provided with
a hand crank 74. By rotation of the hand crank 74 the securing
rollers 58 can be moved into and out of engagement with the inner
side 60 of the L shaped rail 56 as well as be pressed against it.
Figs. 1, 2 and 7 show the belt grinding mechanism 18 in
detail. The grinding belt 76 is guided over a floatingly
supported contact roll 78, over fixedly positioned guide rolls
80, 82 adjacent both sides of the contact roll, and over a drive
roll 86 driven by a drive motor 84. The drive motor 84 is
arranged on a slide 88 which is arranged in a housing 92
containing the floating support 90 for the contact roll 78. A
belt tensioning device 94 serves to tension the grinding belt,
which device cooperates with the slide 88 of the drive motor 84
and biases the drive roll 86 away from the contact roll 78. The
belt tensioning device 94 includes a piston/cylinder unit 96
connected by conductors 98, lOo with a fluid mechanism 102. The
floating support 90 for the contact roll 78 includes longitudinal
guides 104, 106 contained in the housing 92 for the axle 108 on
which the contact roll 78 is rotatably supported. The
longitudinal guides 104, 106 extend perpendicularly to the
surface to be worked, that is radially to the work roll 4. The
axle 108 in the longitudinal guides 104, 106 is yieldingly
engaged with piston/cylinder units 110, 112. In connection with
this, the corresponding pressure spaces of the piston/cylinder
units 110, 112 are connected with one another by connecting
conductors 114, 116~ The piston/cylinder units 110, 112 are
moreover connected by conductors 118, 120 to the fluid apparatus
102. The piston/cylinder units 110, 112 also serve at the same
time for positioning the contact roll against the work surface,
that is the work roll 4. An alignment device 122 serves for
aligning the contact roll in the delivery and application of the
contact roll 78 to the work surface in order to avoid a one-sided
contact and therewith a one-sided grinding of the roll 4. The
alignment device 22 includes threaded shafts 124 on both sides of
the contact roll 78, of which only one shaft is illustrated, with
a rigidly locked contact surface 26, which is displaced
rearwardly a few tenth millimeters from the working position of
the grinding belt. Each threaded shaft 124 is fastened to a
protective cover 128 for the floating support 90, which cover
itself is connected with the axle 108 of the contact roll 78. If
the contact roll 78 is unequally delivered, one of the two
threaded shafts 124 come to rest on the roll 4 and brings the
contact roll into essentially aligned position with the roll.
The control for the belt grinding mechanism through the
fluid apparatus 102, which is preferably an air pressure
apparatus, takes place in a way, not more specifically
illustrated, such that first through the piston/cylinder unit 96
the grinding belt 76 has imparted to it a given tension force.
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In connection with this the contact roll 78 through the axle 108
engages the associated piston/cylinder units llo, 112 in which
the necessary counterpressure is built up. If the contact roll
78 is pushed forwardly against the work surface, that is against
the roll 4, with the help of the piston/cylinder units 110, 112,
the piston/cylinder unit 96 is retracted to the same measure, so
that the once adjusted belt tension remains constant. Upon
grinding the guide rolls 80, 82 serve for the stabilization of
the grinding belt on the contact roll 78, especially when because
of the contour of the work surface the contact roll 78 because of
the floating support 90 takes on an angular position deviating
from its base position. Because of the floating support 90 the
contact roll 78 can follow the contour of a surface to be ground.
Thereby it is possible, without special measures to re-grind an
existing surface especially to improve it. The fluid apparatus
12 provides that during straight line guiding of the belt
grinding mechanism, the pressure at which the contact roll is
applied to the work surface, and which contact roll may for
example may be following a cambered contour of the work surface,
is always held constant.
REFERENCE NUMBER LIST
2 Scraper Apparatus
4 Roll
6 Frame
8 Roller
Scraper
12 Holder
14 Engagement Roller
16 Carrier
18 Belt Grinding Mechanism
Upper Arm
22 Lower Arm
24 Clamping Member
26 Clamping Screw
28 Rod
Clamping Screw
32 Cheek
34 Cheek
36 Horizontal Plane
38 Mounting Plate
Drive Motor
42 Drive
44 Clutch
46 Drive Wheel
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¦48 Toothed Belt
¦ 50 Toothed Wheel
2 Shaft
54 Securing Apparatus
56 L-Shaped Rail
58 Securing Roller
Inner Side
62 Pivot Axle
64 Arm
66 Lever
68 Coupling Member
Spindle
72 Sleeve
74 Hand Crank
76 Grinding Belt
78 Contact Roll
Guide Roll
82 Guide Roll
84 Drive Motor
86 Drive Roll
88 Slide
Floating Support
92 Housing
94 Band Tensioning Device
96 Piston/Cylinder Unit
98 Conductor
100 Conductor
102 Fluid Apparatus
¦104 Longitudinal Guide
106 Longitudinal Guide
108 Axle
110 Piston/Cylinder Unit
112 Piston/Cylinder Unit
l 114 Connecting Conductor
I ¦ 116 Connecting Conductor
118 Conductor
120 Conductor
122 Alignment Apparatus
124 Threaded Shaft
126 Contact Surface
128 Protective Cover
