Information
-
Patent Grant
-
6186762
-
Patent Number
6,186,762
-
Date Filed
Wednesday, January 21, 199826 years ago
-
Date Issued
Tuesday, February 13, 200123 years ago
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Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 425 344
- 425 345
- 425 211
- 425 193
- 118 200
- 118 DIG 15
-
International Classifications
-
Abstract
A pressure roller unit for rotary presses, especially for preparing tablets, with a frame lockable at the rotary press and with two bearing blocks, which can be adjusted at the frame and carry the pressure rollers. To absorb stronger pressing forces and to extensively relieve the press frame of the pressing forces, the frame is formed from a guide column (1), and the bearing blocks (20) are arranged at upper and lower pressure roller mounts (2 and 3), which are guided by the guide column (1) and are adjustable in relation to one another.
Description
FIELD OF THE INVENTION
The present invention pertains to a pressure roller unit for rotary presses, especially for preparing tablets, with a frame lockable at the rotary press and with two bearing blocks which are adjustable at the frame and carry the pressure rollers.
BACKGROUND OF THE INVENTION
Such pressure roller units are used in rotary presses which comprise a frame, a rotor with drive, upper and lower rockers, which guide upper and lower pressure rollers, a frame housing, corner connections, and a cover plate. The forces occurring during the pressing process are directly introduced into the cover plate and the frame via the punches and the rockers and induce vibrations in these membrane-like components due to the pressing forces. These vibrations lead to considerable noise emissions.
A pressure roller unit of this type has been known from U.S. Pat. No. 3,891,375. In this pressure roller unit, the frame comprises upper and lower crossbeams, which are connected by vertical braces, and two columns arranged between these, on which the bearing blocks of the pressure rollers are slidable. The frame is mounted pivotably around a vertical axis in the press frame and forms a part of the press housing in the closed position. The frame may be pivoted by about 90° from a working position into the open position, in which case the drive of the pressure rollers is uncoupled and the pressure rollers are disengaged from the upper and lower punches. The bearing block for the upper pressure roller is connected to the upper crossbeam by means of an adjustable spacer. The spacer is used to set the depth of penetration of the upper punches into the dies of the die disk. The bearing block for the lower pressure roller is connected via a shaft to a hydraulic adjusting unit, which acts on the lower pressure roller for the purpose of setting the tablet thickness. The drawback is that the pressing force passes over the press frame and that the mounting of the bearing blocks for the pressure rollers at the two vertical columns and at the frame pivotable in the press frame is soft and elastic, so that the prior-art pressure roller unit can be used for weak pressing forces only.
SUMMARY AND OBJECTS OF THE INVENTION
The basic object of the present invention is therefore to improve the pressure roller unit of this type.
To accomplish this object, the present invention provides for the frame formed from a guide column and bearing blocks arranged at jointly adjustable upper and lower pressure roller mounts guided by the guide column. As a result, a pressure roller unit which can be used to absorb strong pressing forces is created, whose guide column can be designed as an extremely stable guide column, and the pressing force is prevented from passing over the press frame. Furthermore, the upper and lower pressure roller mounts may be adjusted not only independently from one another, but also together, in order to thus make possible the adjustment of the pressing zone in the case of the parallel adjustment of both pressure roller mounts at a fixed distance from another, or the adjustment of the web height for setting the tablet thickness in the case of the setting of the lower pressure roller mount in relation to the upper pressure roller mount.
In the preferred embodiment, the guide column and the pressure roller mounts have a cylindrical design and the pressure roller mounts are mounted in the guide column. Thus, this forms the housing of the pressure roller unit at the same time.
In another embodiment of the present invention, the upper pressure roller mount is provided with an upper adjusting drive acting on the guide column, and the lower pressure roller mount is provided with a lower adjusting drive, which is mounted in the upper pressure roller mount and acts on same.
Furthermore, the guide column is mounted vertically upright on a frame plate of the rotary press and can be set and locked by means of an adjusting drive. This design and arrangement of the pressure roller unit is possible, because the pressing forces of both pressure rollers are absorbed exclusively by the guide column, and this guide column can thus be arranged freely on a component standing on a massive, rigid and twisting-resistant frame plate of the rotary press.
The various features of the novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1
is a vertical sectional view taken through the pressure roller unit;
FIG. 2
is an enlarged vertical sectional view taken through the upper adjusting drive;
FIG. 3
is an enlarged vertical sectional view taken through the lower adjusting drive;
FIG. 4
is a vertical sectional view taken through the adjustable mounting of the pressure roller unit on a frame plate, and
FIG. 5
is a view of a rotary tabletting press with the pressure roller unit.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The pressure roller for rotary tabletting presses comprises a massively designed guide column
1
of cylindrical cross section, in the cylindrical interior space of which a likewise cylindrical and hollow, upper pressure roller mount
2
and a cylindrical and internally hollow, lower pressure roller mount
3
are slidably mounted, wherein the upper and lower pressure roller mounts
2
,
3
are likewise of a massive and stable design. The adjusting drive
4
for the upper pressure roller
40
is arranged in the upper area of the guide column
1
, and the adjusting drive
5
for the lower pressure roller
50
is arranged in the middle area of the guide column
1
. The upper adjusting drive
4
is used for setting the upper pressure roller
40
and thus the depth of penetration of the upper punch
56
, on which the upper pressure roller
40
acts, and for adjusting the upper and lower pressure rollers
40
and
50
, respectively, jointly, i.e., in parallel, at a fixed distance and thus for adjusting the pressing zone. The adjusting drive
5
for the lower pressure roller
50
is used to set the tablet thickness in relation to the upper pressure roller
40
.
The upper adjusting drive
4
shown in
FIG. 2
on a larger scale contains a gear motor
6
with a gearbox
36
and power take-off shaft
37
. The gear motor
6
is surrounded by a closing cover
42
closing off the guide column
1
in the upward direction, as well as a pot-shaped spindle
7
, which is connected to the power take-off shaft in a non-positive matter. The pot-shaped spindle
7
has external teeth
66
which mesh with the internal teeth
67
of a spindle nut
12
fixed in the cylindrical upper pressure roller mount
2
. To mount the gear motor
6
and the gearbox
36
, two disks
8
,
9
are screwed to the upper end of the guide column
1
. The disk
9
carries the gear motor
6
and the gearbox
36
, and the outer bearing ring of a bearing
10
is clamped between the two disks
8
,
9
, and the inner bearing ring of said bearing
10
carries the upper circumferential edge of the pot-shaped spindle
7
. The pot-shaped spindle
7
is thus freely rotatable in relation to the disks
8
,
9
and the gearbox
36
enclosed inside. The spindle nut
12
is screwed to a flange
11
, which in turn is screwed to the top side of the cylindrical upper pressure roller mount
2
. The likewise hollow cylindrical upper pressure roller mount
2
, which is slidable in the inner cylindrical hole
81
of the guide column
1
by means of sliding elements
68
, can thus be moved vertically adjustably within the guide column
1
by actuating the gear motor
6
and in cooperation with the rotatable spindle
7
and the fixed spindle nut
12
.
On the side shown on the left in
FIGS. 1 and 2
, the upper pressure roller mount
2
has a passage opening
38
, in which the massive bearing block
20
for the upper pressure roller
40
is mounted, wherein the end of the bearing block
20
, which is the right-hand end in
FIG. 1
, is inserted into an inner recess
69
on the inside of the cylindrical upper pressure roller mount
2
by means of a screw
39
. In the area of the head of the screw
39
, a mounting opening
43
, which is closed by a plug
70
, is provided within the cylindrical guide column
1
. On the outer side of the guide column
1
, which is the left-hand outer side in
FIG. 1
, the pressure roller axle
20
carries the upper pressure roller
40
acting on the upper punch
56
with the pressure roller mount
41
comprising two angular ball bearings
71
. A sealing ring
72
cooperating with the rear side of the upper pressure roller
40
is arranged on the outside of the guide column
1
facing the upper pressure roller
40
. The pressure roller axle
20
of the upper pressure roller
40
has a hole
35
for manual adjustment in the central axis
73
.
The adjusting drive
5
for the lower pressure roller
50
, which is shown on a larger scale in
FIG. 3
, contains a gear motor
13
with gearbox
14
, which is mounted in the gearbox flange
16
, which in turn is mounted in an axially longer mounting sleeve
15
, wherein the gearbox flange
16
and the mounting sleeve
15
are tightened with screws
74
in the lower area of the upper pressure roller mount
2
. The mounting sleeve
15
dips with its outer circumference freely into the top end of the lower pressure roller mount
3
, which has a hollow cylindrical design, just as the upper pressure roller mount
2
. The drive shaft
45
of the transmission formed by the gear motor
13
and the gearbox
14
engages a spindle
18
through a clutch disk
75
, which lies on the upper bearing ring of a ball bearing
44
, and the external teeth
76
of the spindle
18
mesh with the internal teeth of a spindle nut
17
fixed in the lower pressure roller mount
3
by means of screws
46
. By actuating the gear motor
13
, the cylindrical lower pressure roller mount
3
, which is slidably mounted in the inner hole
81
of the guide column
1
by means of nonskid elements
68
, like the cylindrical upper pressure roller mount
2
, can thus be moved vertically slidably and adjustably within the guide column
1
by means of the adjusting drive
5
shown in FIG.
3
. This adjusting movement is used to adjust the web height or to set the tablet thickness in relation to the upper pressure roller
40
.
FIG. 3
also shows that compression springs
19
are inserted between the upper pressure roller mount
2
and the lower pressure roller
3
.
The pressure roller axle
20
of lower pressure roller mount
41
is inserted under the adjusting drive
5
in a passage opening
78
in the lower pressure roller mount
3
of the pressure roller axle
20
for the lower pressure roller
50
, and the right-hand end of this pressure roller axle
20
of lower pressure roller mount
41
shown in
FIG. 1
is in turn clamped by means of a screw
39
in a recess
69
on the inside of the lower pressure roller mount
3
, wherein a corresponding mounting hole
43
is closed by means of a plug
70
. The lower pressure roller
50
is also mounted on the corresponding pressure roller axle
20
by means of a pressure roller mount
41
formed by angular ball bearings
71
and is sealed by means of a sealing ring
72
. The lower pressure roller
50
cooperates with the lower punches
56
.
The pressure roller unit shown in
FIG. 1
is mounted with its guide column
1
vertically upright on a massive base plate
29
of the rotary tabletting press and is movable by means of a horizontally operating adjusting drive
79
, which is shown on a larger scale in
FIG. 4. A
truncated cone-shaped mounting flange
22
is fixed within the lower end of the guide column
1
by means of three ring segments
23
distributed over the circumference and of additional ring elements
49
. A tie rod
21
, which passes through a projection
48
at the lower end of the truncated cone-shaped mounting flange
22
, is screwed into the mounting flange
22
within the central axis
73
of the guide column
1
, and the tie rod is movable within an elongated hole
47
, which is provided in the massive base plate
29
of the rotary tabletting press. The tiered
21
passes through the wedge
24
within the stop ring
26
under the base plate
29
, and the stop ring
26
is held by the T-shaped head of the tie rod
21
by means of a dome-shaped piece
80
. The wedge
24
can be loosened and tightened by means of a spindle
25
, which is located rotatably and horizontally nondisplaceably in a vertical bolt
53
at the free end, which is inserted into a vertical blind hole
52
on the underside of the base plate
29
. The spindle
25
has a spindle head
51
on its face. It is connected to a pressure piece
27
acting on the tie rod
21
via a compression spring
28
. For locking, the spindle
25
is rotated at the spindle head
51
until the projection
48
of the mounting flange
22
and the stop ring
26
at the end of the elongated hole
47
, which is the left-hand end in
FIG. 4
, come into contact with base plate
29
. Under the action of the compression spring
28
, the spindle
25
now presses the pressure piece
27
against the spindle
21
. The wedge
24
is displaced at the same time to the left in
FIG. 4
such that the guide column
1
becomes firmly seated on the top side of the base plate
29
of the rotary tabletting press by means of the tie rod
21
.
To pull the pressure roller unit and thus the pressure rollers
40
,
50
forward from the engagement area of the upper and lower punches
56
and
57
, respectively, the spindle
25
is rotated in the opposite direction by means of the spindle head
51
, the compression spring
28
is released, and the wedge
24
is moved away from the stop ring
26
by a small amount, so that the guide column
1
is released from its fixed tensioning at the base plate
29
and can be pulled to the right in
FIG. 4
by continuing to actuate the spindle
25
.
FIG. 5
shows a view of the entire rotary tabletting press, in which the pressure roller unit comprising the guide column
1
and the upper and lower pressure rollers
40
and
50
, respectively, is placed on the base plate
29
and
FIG. 5
shows that the pressing force from the rollers
40
,
50
is transmitted through the guide column
1
to the one end of the guide column connected to the base plate
29
. The upper and lower punches
56
and
57
engage dies of the die plate
55
, not shown. The respective upper and lower pressure rollers
40
and
50
act on the respective punch heads
58
and
59
during the rotation of the die plate
55
of the rotor
30
. The rotor
30
is driven via a drive motor
54
, a toothed belt
31
and two belt pulleys
60
and
61
, as well as a tightening disk
62
. The massive base plate
29
accommodating the pressure roller
1
, the rotor
30
and the drive motor
54
is mounted on the base frame
33
of the rotary tabletting press by means of a plurality of rubber-bonded-to-metal mountings
32
, the rotary tabletting press being carried by frame legs
34
at the installation site. The rotary tabletting press also contains non-carrying frame parts
63
,
64
and
65
, which are used to accommodate the press control and the encapsulation of the rotor
30
and of the pressure roller unit
1
.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.
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LIST OF REFERENCE NUMBERS
|
|
|
1
Guide column
|
2
Upper pressure roller mount
|
3
Lower pressure roller mount
|
4
Adjusting drive for depth of
|
penetration
|
5
Adjusting drive for tablet
|
thickness
|
6
Gear motor
|
7
Spindle (pot-shaped)
|
8, 9
Disk
|
10
Bearing
|
11
Flange
|
12
Spindle nut
|
13
Gear motor
|
14
Gearbox
|
15
Mounting sleeve
|
16
Gearbox flange
|
17
Spindle nut
|
18
Spindle
|
19
Compression spring
|
20
Pressure roller axle
|
21
Tie rod
|
22
Mounting flange
|
23
Ring segment
|
24
Wedge
|
25
Spindle
|
26
Stop ring
|
27
Pressure piece
|
28
Compression spring
|
29
Base plate
|
30
Rotor
|
31
Toothed belt
|
32
Rubber-bonded-to-metal
|
mounting
|
33
Base frame
|
34
Frame leg
|
35
Hole for manual adjustment
|
36
Gearbox
|
37
Drive shaft
|
38
Passage opening
|
39
Screw
|
40
Upper pressure roller
|
41
Pressure roller mount
|
42
Closing cover
|
43
Mounting opening
|
44
Bearing
|
45
Drive shaft
|
46
Screw
|
47
Elongated hole
|
48
Projection
|
49
Ring element
|
50
Lower pressure roller
|
51
Spindle head
|
52
Hole
|
53
Bolt
|
54
Drive motor
|
55
Die plate
|
56
Upper punch
|
57
Lower punch
|
58, 59
Punch head
|
60, 61, 62
Belt pulley
|
63, 64, 65
Frame parts
|
66
External teeth
|
67
Internal teeth
|
68
Sliding element
|
69
Recess
|
70
Plug
|
71
Angular ball bearing
|
72
Sealing ring
|
73
Central axis
|
74
Screw
|
75
Clutch disk
|
76
External teeth
|
77
Internal teeth
|
78
Passage opening
|
79
Adjusting drive
|
80
Dome-shaped piece
|
81
Hole
|
|
Claims
- 1. A pressure roller unit for rotary tablet presses, comprising:pressure rollers; a guide column with an end; two bearing blocks adjustably connected to said guide column, said bearing blocks carrying said pressure rollers, said bearing blocks being arranged at upper and lower pressure roller mounts, said pressure roller mounts being guided by said guide column and being adjustable in relation to one another, said upper and lower pressure roller mounts and said guide column being formed to cancel pressing force from said pressure rollers in said guide column, said guide column being supported only through said one end of said guide column.
- 2. The pressure roller unit in accordance with claim 1, wherein said guide column and said pressure roller mounts have a cylindrical design, and said pressure roller mounts are mounted in said guide column.
- 3. The pressure roller unit in accordance with claim 1, wherein said guide column is provided with an upper adjusting drive acting on said upper pressure roller mount, and said upper pressure roller mount is provided with a lower adjusting drive mounted in said upper pressure roller mount and acts on said lower pressure roller mount.
- 4. The pressure roller unit in accordance with claim 3, wherein said upper adjusting drive comprises:a gear motor; a gearbox connected to said gear motor; a power take-off shaft connected to said gear box; and a pot-shaped spindle connected to said power take-off shaft, said spindle having external teeth; a spindle nut fixed in said upper pressure roller mount, said upper pressure roller mount being cylindrical, said spindle having external teeth meshing with internal teeth of said spindle nut.
- 5. The pressure roller unit in accordance with claim 3, wherein said upper adjusting drive comprises:a gear motor; a gearbox connected to said gear motor; a power take-off shaft connected to said gear box; and a spindle driven by said power take-off shaft, said spindle having external teeth; a spindle nut fixed to said upper pressure roller mount, said spindle nut having internal teeth meshing with said external teeth of said spindle.
- 6. The pressure roller unit in accordance with claim 1, further comprising:a base plate, said guide column being mounted vertically upright on said base plate; and a guide column adjusting drive, said guide column being adjustable and lockable by means of said guide column adjusting drive.
- 7. The pressure roller unit in accordance with claim 6, wherein said guide column adjusting drive includes:a mounting flange fixed within a lower end of said guide column; a tie rod screwed into said mounting flange, said tie rod passing through said base plate; a stop ring, said tie rod passing through said stop ring; a spindle; and a wedge in contact with said base plate, said wedge being loosened and tightened by means of said spindle.
- 8. A pressure roller unit for rotary tablet presses, comprising:a guide column having only one end connected to a base frame of the rotary tablet press; a first pressure roller mount movably connected to said guide column; a first pressure roller connected to said first pressure roller mount, said first pressure roller engaging with a first set of punches of said rotary tablet press, said first pressure roller mount being formed to transmit pressing force from engagement of the first set of punches with said first pressure roller to said first pressure roller mount; a second pressure roller mount movably connected to said guide column and movable in said guide column with respect to said first pressure roller mount; a second pressure roller connected to said second pressure roller mount, said second pressure roller engaging with a second set of punches of said rotary tablet press, said second pressure roller mount being formed to transmit pressing force from engagement of the second set of punches with said second pressure roller to said second pressure roller mount, said first and second mounts being connected to have said pressing forces from said first and second set of punches cancel within said guide column.
- 9. The pressure roller unit in accordance with claim 8, further comprising:an adjusting drive for moving said first and second pressure roller mounts together with respect to said guide column.
- 10. The pressure roller unit in accordance with claim 9, further comprising:another adjusting drive for moving said second pressure roller mount with respect to said first pressure roller mount.
- 11. The pressure roller unit in accordance with claim 8, further comprising:a base plate mounted on said base frame of the rotary tablet press; a guide column adjusting drive connected to said base plate and said end of said guide column for moving said guide column with respect to said base plate and locking said guide column to said base plate.
- 12. The pressure roller unit in accordance with claim 10, further comprising:a base plate mounted on the base frame of the rotary tablet press; a guide column adjusting drive connected to said base plate and said end of said guide column for moving said guide column with respect to said base plate and locking said guide column to said base plate.
- 13. The pressure roller unit in accordance with claim 8, wherein:said guide column exclusively transmits any remaining said pressing force from said pressure rollers through said end of said guide column.
- 14. A pressure roller unit for rotary tablet presses, comprising:pressure rollers; a guide column with an end; two bearing blocks adjustably connected to said guide column, said bearing blocks carrying said pressure rollers, said bearing blocks being arranged at upper and lower pressure roller mounts, said pressure roller mounts being guided by said guide column and being adjustable in relation to one another, said upper and lower pressure roller mounts and said guide column being formed to cancel pressing force from said pressure rollers in said guide column, said guide column being supported only through said one end of said guide column, said guide column and said pressure roller mounts having a cylindrical design, and said pressure roller mounts being mounted in said guide column.
Priority Claims (1)
Number |
Date |
Country |
Kind |
197 05 092 |
Jan 1997 |
DE |
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US Referenced Citations (9)
Foreign Referenced Citations (4)
Number |
Date |
Country |
165401 |
Sep 1904 |
DE |
1 933 490 |
Apr 1970 |
DE |
0 460 295 A1 |
Dec 1991 |
EP |
2 252 917 |
Jun 1975 |
FR |