U.S. patent application number 10/697292 was filed with the patent office on 2005-05-05 for grinding-band swaying device for a band grinding machine.
Invention is credited to Chuang, Po Chang.
Application Number | 20050095965 10/697292 |
Document ID | / |
Family ID | 34435485 |
Filed Date | 2005-05-05 |
United States Patent
Application |
20050095965 |
Kind Code |
A1 |
Chuang, Po Chang |
May 5, 2005 |
GRINDING-BAND SWAYING DEVICE FOR A BAND GRINDING MACHINE
Abstract
A grinding-band swaying device for a band grinding machine
includes a motor pivotally connected with a machine base and
driving an endless grinding band around two rollers and forming a
fulcrum for swaying, a speed-reducing unit and an eccentric wheel.
The speed-reducing unit is positioned under the motor, having a
shaft connected with the eccentric wheel. An elastic compressing
unit is provided between the speed-reducing unit or the motor and
the machine base, and then the eccentric wheel is kept to
elastically urge the machine base. When the motor together with the
speed-reducing unit rotates the eccentric wheel, the speed-reducing
unit, the motor and the roller sway regularly with the fulcrum and
then the endless grinding band moves forward and also sways
regularly synchronously to perform grinding against a work with
grinding angles constantly altered to achieve balanced grinding
result.
Inventors: |
Chuang, Po Chang; (Taiping
City, TW) |
Correspondence
Address: |
TROXELL LAW OFFICE PLLC
SUITE 1404
5205 LEESBURG PIKE
FALLS CHURCH
VA
22041
US
|
Family ID: |
34435485 |
Appl. No.: |
10/697292 |
Filed: |
October 31, 2003 |
Current U.S.
Class: |
451/304 |
Current CPC
Class: |
B24B 47/00 20130101;
B24B 21/04 20130101 |
Class at
Publication: |
451/304 |
International
Class: |
B24B 049/00 |
Claims
What is claimed is:
1. A grinding-band swaying device for a band grinding machine, said
band grinding machine having a worktable on a machine base, an
upper frame positioned on the worktable, two upright rollers
positioned at two ends of said upper frame, one of said two rollers
separated from said upper frame and connected with and driven by a
motor, an endless grinding band extending around and moved by said
two rollers, said grinding band grinding a work placed vertically
on said worktable, said grinding-band swaying device comprising: A
pivotal plate provided near said machine base and connected with
said motor, said pivotal plate pivotally connected with a
corresponding wall of said machine base, said pivotal plate
combined with an elastic compressing unit at a preset location,
said elastic compressing unit elastically urging said motor towards
said machine base, said motor having an upper spindle extending up
from its top and a lower spindle extending down from a bottom, said
upper spindle connected with a shaft of said roller: A
speed-reducing unit positioned under said motor and connected with
and driven by said lower spindle, said speed-reducing unit
diminishing the rotating speed of said lower spindle and
transmitting it to a shaft: An eccentric wheel fixed on and driven
by the shaft of said speed-reducing unit, said eccentric wheel
keeping elastic compressing against a wall of said machine base by
elastic pressing of said motor against said machine base: Said
eccentric wheel overcoming the elastic pressing of said elastic
compressing unit to force said speed-reducing unit, said motor and
said roller sway outward when said eccentric wheel rotates, said
eccentric wheel also swaying inward by recovery of the elasticity
of said elastic compressing unit so that said eccentric wheel may
force said speed-reducing unit, said motor and said roller sway
upward and downward regularly (in other words, reciprocate).
2. The grinding-band swaying device for a band grinding machine as
claimed in claim 1, wherein said speed-reducing unit consists of a
shell fitting firmly around a lower portion of said motor, a bottom
cap closed up the bottom of said shell, a transmission unit
arranged in said shell, said transmission unit having gears and
endless belts for transmitting rotating force and for reducing
rotating speed, a last one of said gears having a shaft extending
up through said shell and driving said eccentric wheel to rotate, a
first one of said gears having its shaft extending down to said
bottom cap and sliding thereon to control tightness of said endless
belts.
3. The grinding-band swaying device for a band grinding machine as
claimed in claim 1, wherein said elastic compressing unit consists
of a position bolt extending from said pivotal plate connected with
said motor to the inner side of said wall of said machine base, a
coil spring fitting around an inner portion of said position bolt
inside said wall, a nut screwing with an end of said bolt and
compressing said coil spring so said coil spring always urges
against an inner surface of said wall of said machine base, thus
said motor and the connecting components kept elastically urging
towards said machine base.
4. The grinding-band swaying device for a band grinding machine as
claimed in claim 1, wherein said elastic compressing unit is
provided on said speed-reducing unit, consisting of a shaft with
one end connected with a preset location of said wall of said
machine base and with the other end extending through and out of
said pivotal plate with a coil spring fitting around the outer
portion and then screwing tightly with a nut so that said coil
spring may always elastically compress said pivotal plate together
with said speed-reducing unit and the connecting components on said
same unit toward said machine base.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a band grinding machine,
particularly to one having a grinding-band swaying device possible
to sway the grinding band of a band grinding machine for regularly
changing grinding angles of the grinding band against a work in
order to upgrade ground quality of a work.
[0003] 2. Description of Prior Arts
[0004] A known conventional band-grinding machine shown in FIG. 1
includes a machine base 11, a worktable 12, a grinding-band
wheelbase 13 and a motor 14. The worktable 12 is positioned on the
machine base 11, with the grinding-band wheelbase 13 pivotally
connected on the machine base 11. Further, two rollers 131 are
positioned at the left side and the right side of the worktable 12,
and an endless grinding band 132 extends around the two rollers
131. The motor 14 is fixed at the left side of the machine base
just under the left roller 131 and connected with a swaying member
15, having its output end combined with the left roller 131 so as
to drive the grinding band move around the two rollers 131.
Further, an eccentric device 16 is provided to work with the motor
14, consisting of a main wheel 161 combined with the motor 14, and
an eccentric shaft 1611 fixed laterally on the main wheel 161, and
a swaying shaft 162 pivotally connected with the eccentric shaft
1611. The swaying shaft 162 is firmly connected with the endless
grinding band 13. Therefore, when the motor 14 rotates the main
wheel 161, the eccentric shaft 1611 makes eccentric movement so
that the grinding band 132 may sway laterally back and forth
together with linear straight movement, caused by the stationary
condition of the grinding-band wheelbase 13 and the swaying shaft
162.
[0005] However, the eccentric device 16 in the conventional
band-grinding machine 10 has a disadvantage of a complicated
structure, and the swaying shaft 162 has one end directly connected
firmly with the band-grinding wheelbase 13. Then the main wheel 161
indirectly actuates the swaying shaft 162 Via the eccentric shaft
1611, so the swaying shaft 162 may be interfered by the connected
end with the grinding-band wheelbase 13, resulting in unsmooth
operation of the eccentric swaying. Moreover, the combining
structure of the two ends of the swaying shaft 162 has to share the
load of the motor 14 so the eccentric shaft 1611 may become
gradually worn off by long-term usage, with the service life of the
machine possible to be shortened. Further, an universal joint would
have to be used for the connecting locations for the swaying shaft
162 and the grinding-band wheelbase 13 and the eccentric shaft
1611, the structure should become quite complicated to end in high
cost of the conventional band grinding machine.
SUMMARY OF THE INVENTION
[0006] A principal objective of the invention is to offer a
grinding-band swaying device for a band grinding machine, which has
rollers driven by a motor so as to sway a grinding band back and
forth in the lengthwise direction so that grinding angles between a
work and the grinding band vary incessantly to achieve balanced
surface of the ground portion. Thus, the service life of the
grinding band can be prolonged by constant alteration of the
grinding location of the grinding band against the work.
[0007] Another objective of the invention is to offer a
grinding-band swaying device for a band grinding machine, having an
eccentric wheel and an elastic compressing unit not fixed together
to ensure smooth swaying of the grinding band and to prevent the
swaying device from getting damaged.
BRIEF DESCRIPTION OF DRAWINGS
[0008] This invention will be better understood by referring to the
accompanying drawings, wherein:
[0009] FIG. 1 is a perspective view of a conventional band-grinding
machine;
[0010] FIG. 2 is a front view of an eccentric device in the
conventional band-grinding machine;
[0011] FIG. 3 is a grinding-band swaying device for a band-grinding
machine in the present invention;
[0012] FIG. 4 is an exploded perspective view of the grinding-band
swaying device in the present invention;
[0013] FIG. 5 is a front view of the band-grinding machine in the
present invention;
[0014] FIG. 6 is a front view of a speed-reducing unit in the
present invention;
[0015] FIG. 7 is a side view of an eccentric wheel with related
portion in the present invention;
[0016] FIG. 8 is a side view of the eccentric wheel under motion in
the present invention; and,
[0017] FIG. 9 is a side view of another embodiment of an elastic
compressing unit in the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMGODIMENT
[0018] A preferred embodiment of a grinding-band swaying device for
a band grinding machine in the present invention, as shown in FIGS.
3, 4 and 5, includes a worktable 21 positioned on a machine base
20, an upper frame 30 provided n the worktable 21, two vertical
rollers 40 combined with the upper frame 30, a motor 50 driving one
of the rollers 40, an endless grinding band 60 extending around the
two rollers 40, a speed-reducing unit 70 and an eccentric wheel
80
[0019] The motor 50 is fixed with an pivotal plate 51 at an inner
side, and the pivotal plate 51 has two studs 511 formed to extend
inward from two ends, cooperating with a rotatable shaft 52
pivotally connected with the machine base 20 to function as an
eccentrically rotating point. The motor 50 has an upper spindle 53
and a lower spindle 54 respectively connected with and rotating one
of the two rollers 40. Further, an elastic compressing unit (S) is
provided on the pivotal plate 51, which has a hole 512 in a lower
portion, a bolt 55 screwing through the hole 512 in the wall 22 of
the machine base 20, with a coil spring 56 fitting around a outer
portion of the bolt 55 and with a nut 57 screwing tightly with the
bolt 55 for compressing the spring 56. Then the spring 56
elastically presses against the wall 22 of the machine base 20,
having resilience to push back the motor 50 to its original
position, always keeping the eccentric swaying function.
[0020] The speed-reducing unit 70 is provided under the motor 50,
as shown in FIG. 6, consisting of a shell 71, a bottom cap 72, and
a transmitting unit 73. The shell 71 has an upper combining ring
711 just fitting firmly around a lower portion of the motor 50, and
a bottom portion with a hole 712 near the ring 711. The bottom cap
72 closes up the bottom of the shell 71, having an intermediate
slot 722, and two slide slots 723 at two sides of the intermediate
slot 722, with all the sliding direction of the three slots 722 and
723 being the same. Further, a connector 724 is positioned on the
intermediate slot 722, having two ends screwed with the two slide
slots 723 with screws with the screwed locations adjustable by
sliding.
[0021] The transmission unit 73 consists of a first gear 731 of a
large diameter, an endless belt 732 extending around the first gear
731 and the lower spindle 54 of the motor 50, a first shaft 733
fixed through the center of the first gear 731 and having an
annular teeth 7331 around its upper portion and its lower end
passing though the connector 724 to be fixed in the slot 72.
Therefore, the first gear 73 can move up in the intermediate slot
722 together with the connector 724. Further the transmission unit
73 has a second gear 734, and a second shaft 736 extending through
the center of the second gear 734 and fixed in the hole 712 of the
shell 71. Then the output force of the motor 50 is reduced by the
transmission unit 73 and transmitted as output by the second shaft
73. In addition, the two endless belts 732 and 735 are tightened
properly by adjustment by the first gear 731.
[0022] The eccentric wheel 80 is fixed with the second shaft 736 of
the speed reducing unit 70, kept to sway eccentrically toward the
inner direction and pressing against the wall 22 of the machine
base 20. In this embodiment, a press plate 23 of a low friction
coefficient and of anti-grinding feature is additionally provided
at the outer side of the wall 22, permitting the eccentric wheel 80
rotate much smoothly against the press plate 23.
[0023] In using, referring to FIGS. 5, 7 and 8, when the motor 50
is started, the spindle 51 rotates the roller 40 to drive the
grinding band 60 to make grinding action to one side, and the lower
spindle 54 also rotates the speed-reducing unit 70 to reduce the
rotating speed of the second shaft 736, which then rotates the
eccentric wheel 80, which then is held elastically urging the press
plate 23 of the machine base 20 due to the coil spring 56
positioned between the pivotal base plate 51 and the machine base
20. Thus, the eccentric wheel 80 is ensured to be kept in an
elastic compressing condition against the press plate 23 so the
eccentric wheel 80 and the press plate 23 can produce correct
interaction. When the eccentric wheel 80 increase its biasing
force, the speed-reducing unit 70 along with the motor 50 and the
roller 40 may rotate eccentrically by the pivotal connecting point
of the motor 50 and the machine base 20. Then the roller 40 on the
motor 50 sways a little inward, and then the grinding band 60 on
the roller 40 also produce lengthwise upward biasing during moving
around the two rollers 40, constantly altering grinding angles
against a work being ground, In the same principle, when the
biasing distance gradually decreases, the grinding band produces
lengthwise downward biasing. Thus the grinding band 60 makes
regular biasing during moving around the two rollers 40 by means of
the swaying action of the speed-reducing unit 70 and the motor 50,
incessantly altering grinding angles against a work being ground,
resulting in the surface of a work with good ground quality.
[0024] Next, as shown in FIG. 9, another embodiment of an elastic
compressing unit (S) is illustrated, consisting of a shell 71
provided with a pivotal plate 713, a shaft 24 provided having one
end contacting the machine base 20 and the other end passing
through pivotal plate 713 and screwed with a nut 26, with a coil
spring 25 fitting around the portion extending out of the pivotal
plate 713. The spring 25 can elastically push the pivotal plate 713
towards the machine base 20. Therefore, the pivotal plate 713 may
elastically bias towards the machine base 20, together with the
whole speed-reducing unit 70, the motor 50 and the roller 40
connected with the motor 50. Likewise, the eccentric wheel 80 on
the speed-reducing unit 70 may have elasticity against the machine
base 20, rotating to actuate the motor 50 together with the roller
40 to sway upward and downward lengthwise. It is worthy to say that
the motor 50 and the speed-reducing unit 70 are composed integral
as one component, and so long as the motor 50 or the speed-reducing
unit 70 is provided with the elastic compressing unit (S), the
connecting members on the motor 50 or the speed-reducing unit 70
can be swayed towards the machine base 20 to force the eccentric
wheel 80 kept elastically urging the machine base 20 or the wall 22
beneficial for swaying action.
[0025] While the preferred embodiment of the invention has been
described above, it will be recognized and understood that various
modifications may be made therein and the appended claims are
intended to cover all such modifications that may fall within the
spirit and scope of the invention.
* * * * *