Setting device for bending layer material more particularly paper

Information

  • Patent Grant
  • 6302678
  • Patent Number
    6,302,678
  • Date Filed
    Friday, March 27, 1998
    26 years ago
  • Date Issued
    Tuesday, October 16, 2001
    22 years ago
Abstract
For levelling webs of paper (3) gaps (20) are provided, each defined by a deflection roll (17) and a stationary bending face (16). For changing the wrap angle at the bending face (16) and also for non-bended passage of the web (3) through the device (1) the deflection roll (17) is transferable into varying positions powered by a positioning device (30). Thereby high speed operation with reliable function and simple construction are achieved.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The invention relates to a device with which flexural or elastic materials can be worked in achieving a desired non-stressed shape, such as a flat shape. Such materials may be substrates or other rollable materials having a constant thickness which are worked as individual sheets or as an endless material web.




2. Description of the Background




Due to it being supplied as a reeled material, for instance, paper tends to curl, i.e. a portion of the web spread out flat is subject to an inherent bending stress and thus tends to curve or curl to relieve the stresses on release of external forces. However, it may also be wanted to bend or work a flat layer which is planar when free of stress so that it assumes a curved position. In any case, bending breaks a predetermined stress by moving the material on its face to which it is to be curved relative to a bending face. In this arrangement the material defines an angle of wrap in the portion coming into contact with the bending face. This angle of wrap is determined by the position of a deflector or guide for the material next the bending face. This deflector may be provided upstream and/or downstream of the bending face. For modifying the angle of wrap or for optionally working both faces of the material the deflector arrangement and the bending face means are expediently adjustable relative to each other. For this purpose the bending face may be positioned on the device frame so that it can be adjusted relative to the deflector during the entire bending operation, e.g. to transpose material sections in sequence having continuously changing tendencies into the same, non-stressed planar shape or the like. Such an adjustment may, however, result in a bulky configuration involving complicated control and inertia in control movements which makes it difficult to quickly react to varying curl tendencies or other properties of the material. If the length of the material section tensioned freely or linearly between the bending face and the deflection face is greater than the deflection radius of the deflection face the aforementioned drawbacks are likewise given and in addition to this material section may oscillate at high running speeds to the detriment of consistent good quality working.




OBJECTS OF THE INVENTION




An object is to overcome the drawbacks of known configurations or of the kind described. A wide variety of stresses should be introduceable into the material by simple constructional means.




SUMMARY OF THE INVENTION




In accordance with the invention the guiding face forming the deflection face and the bending face define as boundaries a relatively narrow gap which permits material to pass preferably free of compression stress. The clear width or the like of the gap is variable so that its minimum width is many times smaller than the cited deflection radius when the material wraps the bending face. This width can be measured in an axial plane of the deflection passing through the center of the bending face or of the angle of wrap. The minimum width may also be smaller than half, a quarter or a tenth of the deflection radius or smaller than 50 or 30 times the thickness of the material so that the free running zone between the two guiding faces is maximally as large as the deflection radius or smaller as compared thereto corresponding to one of the cited values.




Although in this case too, the bending face is positionally adjustable during bending operation it is, however, particularly expedient when thereby only the deflection is adjusted transverse to the deflection axis since then the distances and time required maximally for positioning are relatively small. The deflection face can thus be set tangentially to the plane of a flank connecting to the bending face and the tangential point can be continuously displaced from a position remote from the flank and opposing the bending face up to the flank face and a zone behind the bending face. This is especially achieved when the associated positioning axis is located away from the deflection axes of the deflection face upstream or downstream next to the bending face and thus the gap width is slightly altered by the positioning motion.




A web of paper to be subsequently worked is expediently secured with its leading edge to the overlapping trailing edge of an advanced paper web, e.g. by an adhesive tape before these ends or the seam reaches the working station. If the seam is passed on an arc or angle of wrap through the working engagement at the bending face or the like it may easily tear. This is why the guiding faces are mutually displaceable in a sudden short impulse such that the seam can be guided past one or both guiding faces without curvature or even contact, thus excluding damage.




Although the device can be made for bending engagement only on one face of the material, it is expediently configured for alternating bending engagement on both faces. For this purpose two separate deflecting faces are displaceable in common and two separate bending faces are mutually and separately adjustable relative to the device frame. The deflecting faces provided for this purpose, on the one hand, and the bending faces on the other are facing each other and are minimally spaced from each other by a spacing which is maximally as large as the deflection radius or smaller. The deflecting faces may be formed by rotational faces or rollers, the clear width there between as measured in their common axial plane being smaller than their radius. At both deflecting faces and at the bending face the material may be simultaneously guided and thus curved alternatingly in opposite directions.




In accordance with the invention fluid or suction means is provided with which particles of dust, paper or the like can be permanently exhausted more particularly in the region of the guiding faces or gap. A suction port adjoining the gap or the guiding faces is shaped expediently, as viewed axially, other than circular, more particularly oblong so that in the associated gap boundary only a single suction orifice extending over the full gap length is necessary. Such a configuration is substantially simpler to produce than orifices arranged in a grid pattern.




The bending face is expediently arranged on a plate or slat-like or similar type reversible body which can be replaced as a module without needing to destroy any part of it or its fastener means and can be thus reinserted in reversed positions so that a further bending face of three, four or more such faces is in place for workingly engaging the material. Accordingly, these bending faces working alternatingly may be configured in one part. However, the bending face may also be formed by a rotational face, for example, a round rod, instead of an edged face.




To facilitate changing the bending body, together with a support body such as a rod, where necessary, its fastening to the device frame is suitable for radial removal, i.e. for removal transversely to the longitudinal direction of the bending face or to the width extension of the material. Removing or changing can thus also be done when the material regularly passes through the device, the same applying also to the deflector arrangement or the individual deflector bodies.




In a further aspect of the invention the guiding faces are slantingly adjustable relative to each other or relative to the material or the running direction or the like, more particularly as viewed at right angles to the longitudinal direction of the guiding faces so that varying wrap angles or gap widths can be achieved over the width of the material. This adjustment is possible during bending operation.











BRIEF DESCRIPTION OF THE INVENTION




Example embodiments of the invention are explained in more detail in the following and illustrated in the drawings in which:





FIG. 1

is a side view of a device for a multi-ply material web,





FIG. 2

is a partially sectioned view as seen from the right of a single subdevice of the arrangement as shown in

FIG. 1

,





FIG. 3

is a section through the bending tools as shown in

FIG. 2

,





FIG. 4

is a view of a bending body as shown in

FIGS. 2 and 3

,





FIG. 5

is a longitudinal section through the bending body as shown in

FIG. 4

,





FIG. 6

is a scrap view of the bending body as shown in cross-section in

FIG. 3

on an enlarged scale,





FIG. 7

is a scrap view of the suction connection of the bending body,





FIG. 8

is a cross-sectional view of the mounting arrangement of one end of the bending body,





FIG. 9

is a cross-sectional view of the bearing means of the other end of the bending body, and





FIG. 10

is a scrap view of a further embodiment of the subdevice as shown in FIG.


1


.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




As shown in

FIG. 1

multiple equal bending or subdevices


1


are arranged in a station


2


horizontally juxtaposed and spaced from each other by an amount which is smaller relative to the space requirement for a device


1


, each of which is designed to work a separate material


3


in a working zone. In these working zones the materials


3


have parallel running directions


4


inclined downwards in running planes


5


parallel to each other. Each device


1


is arranged as a module for facilitated removal from a frame


6


. A multi-layer material web


7


from which the webs


3


located initially congruently on each other is fed horizontally and above the devices


1


to station


2


from separate reel stands, firstly aligned at a deflection


9


and then downstream thereof the individual materials


3


are each deflected in sequence from the web


7


at an upper deflection


8


and fed extended directly to the associated device


1


. From the working zone each material


3


is fed extended to devices


11


located below at which the materials


3


are placed one on the other in sequence to again form the web


7


.




In front and behind of the devices


1


the frame


6


comprises a portal


12


and


13


respectively each composed of rods, the vertical supports of these portals being connected to each other via horizontal girders


14


located on both sides of the material


3


. On their tops these members


14


mount the device modules


1


and can be removed together therewith as a unit from the remaining frame


12


,


13


. The upper ends of portals


12


,


13


are likewise interconnected with girders on which the deflectors


8


or rolls are rotatively mounted in sequence.




The single-layer material


3


is fed as an endless web to the working zone of the individual devices


1


via a cylindrical guide and deflection face


15


which the material


3


wraps over an angle of maximally 90°. From face


15


the material passes stretched directly to a guide or bending face


16


formed by a corner edge rounded in cross-section. Guide face


15


is formed by a rotating roll or deflector body


17


and the bending face


16


by a stationary bending body


18


comprising rectangular flat cross-sections throughout, which like deflector body


17


covers the full width of the material. Any soilage appearing in the working zone or in the vicinity of gap


20


is continuously removed pneumatically by a flow, for example by suction means


19


. The plane


10


of gap


20


slanting downwards in the direction


4


coincides with the bending flank of the bending face


16


which directly opposes guiding face


15


and is formed by an entirely planar larger face


21


of body


18


. The running plane


5


is steeper than face


21


so that the material


3


passes through the gap


20


from one gap boundary


15


to the opposite gap boundary


16


at an acute slanting angle before then being deflected on bending face


16


downwards and away from face


15


over an angle of less than 90°. The free length of material


3


between the two boundaries


15


,


16


is extremely short, but continuously variable. This length is smaller than the largest cross-sectional extension of body


17


or


18


or is half or a quarter thereof.




Guiding face


15


is curved about a horizontal deflector axis


22


, oriented parallel to running plane


5


and at right angles to direction


4


. Bending face


16


is curved about a bending axis


24


orientable parallel thereto. The two convex curved faces


15


,


16


greatly differ in their radius of curvature, the radius of face


15


being at least 10 to 20 times or 30 times larger than the radius of face


16


. Face


15


is adjustable about a positioning axis


25


oriented parallel to axis


22


, the positioning axis


25


being fixed on frame


6


and located on the side of axis


22


or of body


17


facing away from gap


20


or plane


10


.




The two ends of body


17


are secured or rotationally mounted on two supporting cheeks


26


, each of which is rotationally mounted about axis


25


over at least 120° or 360° with a bearing


28


and


29


respectively located at the corresponding outer side. Unit


17


,


26


,


27


can be radially removed from frame


6


, where necessary, together with bearings


28


,


29


. For precise, continuous adjustment about axis


25


positioning means


30


are provided which comprise an upright rotational motor


31


and a gear such as an angular gear


32


directly flanged thereto. Gear


32


is secured to the upper side of one member


14


and operates self-locking. The corresponding cheek


26


is secured directly to the freely protruding output journal of gear


32


so that the latters gear bearing directly forms the corresponding sole bearing


28


for positioning unit


17


,


26


,


27


, eliminating the need for any further separate or frame-fixed bearing on this side. The positioning means


30


,


40


,


42


,


43


or the suction means


19


may be arranged optionally on both sides of gap


20


by e.g. arranging gear


32


optionally on each one of members


14


and the connection


52


,


53


,


54


,


55


optionally in the region of each one of members


14


. Due to this arrangement the operator side of the device


1


may be located optionally on either the one side or the other and, where necessary, maintained free of means


19


,


30


,


42


.




For adjusting unit


17


,


26


,


27


control means


33


are provided on the side of gear


32


facing away from this unit. Means


33


comprise a control cam


34


located in axis


25


of the journal and arranged directly on the other journal of the same gear shaft. The periphery of cam


34


acts on a sensor


35


, such as an inductive transducer, so that by setting a variable signal value the positioning means


30


is stopped when the corresponding position of guiding body


17


is attained. An analog indication of the position is provided by an optical display


36


on the outer side of the other bearing


29


.




The flat or rod-type body


18


having constant outer cross-sections full-length is secured replaceably to a rod or supporting body


37


which is larger in cross-section and which is cross-sectionally configured as a flat rectangular tubular body carrying intimately adjoined body


18


on one of its two wider outer faces. Due to this the edge faces of body


18


adjoining edges


16


are located in the planes of the two outer faces of body


37


which are narrower or located at right angles thereto. The ends of unit


18


,


37


, more particularly only the ends of body


37


are rigidly connected with circular disk-shaped flanges


38


which are replaceably fixed to plate-shaped supporting flanges


38


′ of frame


2


by axial bolts which can be screwed into place toward outside. Once the axial bolts have been released unit


18


,


37


can be removed radially from supporting flanges


38


′ or conversely reinstalled.




Face


16


is manually adjustable by positioning means


39


or


40


relative to unit


17


,


26


,


27


and frame


6


separately about two positioning axes


45


,


46


located at right angles to each other, namely by the positioning means


40


during operation and by the positioning means


39


when operation is stopped. Axis


46


oriented parallel to face


16


and to axes


22


,


25


is located on the side of face


16


facing away from gap


20


,


10


roughly in the center axis of supporting body


37


or of the associated flanges


38


. For passage of the cited axial bolts these flanges


38


comprise slots curved about axis


46


so that the inclination of the face


16


and gap flank


21


can be steadily varied and then locked in place by clamping action of the axial bolts. The flank


21


is located in one position of unit


15


,


26


,


27


at right angles to the common axial plane


47


of axes


22


,


25


, this axial plane intersecting flank


21


directly adjacent to face


16


. From this position planes


10


,


47


can be steadily displaced in both opposing directions. Also so that plane


47


spacedly opposes face


16


and thus slants relative to plane


10


. In the cited center position the clear width of gap


20


is at a minimum, it increasing steadily when varied in both directions as is evident from the positions indicated dot-dashed in FIG.


3


. The minimum gap width is expediently more than one millimeter and less than three or five millimeters. Positioning movements of both positioning means


30


,


39


result in such changes, it only being the positioning means


39


which establishes the smallest possible gap width.




Positioning means


40


permit mutually slanting adjustment of face


16


and axes


24


,


46


, on the one hand, and of guiding face


15


and axes


22


,


25


on the other. The cited gap width settings remain constant over the positioning length of positioning means


40


. Positioning means


40


set the one end, remote from positioning means


30


, of unit


18


,


37


about positioning axis


25


whilst the other end of this unit merely privots about frame-fixed axis


45


, i.e. including the corresponding supporting flange


38


′ in each case. Axis


45


is always located in the same axial plane of axis


25


and is laterally juxtaposed with the axial planes of axes


22


,


24


,


46


oriented parallel thereto. It is possible by the positioning means


30


to translate axis


22


also in this common axial plane. The supporting flange


38


′ for the one flange


38


is adjustable by a guide


41


curved about axis


25


, this guide comprising a guide pin engaging a curved slot with zero diametral clearance and rigidly connected to supporting flange


38


′. The mounting about axis


45


oriented transverse or inclined to flank


21


or plane


10


is formed by a joint


42


or a mount comprising a joining pin located fixed to frame


6


in axis


45


.




Each of the bearings


41


,


42


comprises a mounting body


48


fixed to frame


6


laterally on the inside of the corresponding member


14


. The one mounting body carries guide


41


and the other, in a bifurcated arrangement, the joining pin which passes through the corresponding supporting flange


38


′ between the forked arms of the corresponding mounting body


48


. After this adjustment the unit


18


,


37


needs to be locked only in the region of guide


41


by suitable means


43


, for example by clamping. For this purpose a manually lever-operable clamping device is provided with which guide


41


can be axially tensioned relative to the corresponding mounting body


48


. To facilitate manual adjustment along the guide


41


the corresponding supporting flange


38


′ is provided with a radially protruding handle


44


adjoining the inner side of this mounting body


48


. Clamp


43


is accessible directly on the underside of the corresponding member


14


.




Body


18


as shown in

FIGS. 4

to


6


consists of an integral metal body the surface of which is coated overall or at least in the region of the four longitudinal edges


16


e.g. with a vacuum-deposited film of a harder substance, such as ceramic oxide film or the like maximally a tenth or half a tenth of a millimeter thick, for example. Body


18


is optionally turnable about its longitudinal center axis and about its transverse axis oriented at right angles thereto so that with respect to member


37


each of its four edges


16


can be optionally brought into the same working position for engaging the material


3


. For this purpose fastening means


49


for reversible tool


18


comprise on both flat sides of reversible bit


18


countersinks for fastener bolts with which tool


18


can be tensioned optionally with both flat sides against the corresponding flat side of member


37


. Edges


16


may have different radii of curvature so that one and the same tool


18


has working edges


16


for adapting to various working requirements.




Suction means


19


are stationary or not exposed to positional changes in operation and comprise a slot-shaped fluid or suction orifice


50


passing transversely through tool


18


in the middle between edges


16


. Opening


50


is oriented parallel to edges


16


and in line between countersinks


49


. The corresponding wall of member


37


is provided with a coincidental fluid orifice connecting the port of orifice


50


located in flank


21


to a flow passage


51


. Passage


51


is bounded solely by the inner sides of profile


37


, runs full length over the latter and has at one or both ends constricted connectors


52


which are provided for both gaps


20


at the remote outer sides of support flanges


38


′ and laterally adjacent to


41


or axis


45


. To connectors


52


a flexible tube


53


, e.g. a hose, connects and traverses the underside of the corresponding member


14


. The other end of this tube is connected via a slanting connection


55


to a longitudinal passage


54


. Secured to the other longitudinal section of each member


14


is one such longitudinal passage


54


! having a rectangular or square cross-section, into the side wall of which the connection


55


issues at an acute angle inclined to the flow direction in passage


54


to eliminate flow losses. The end of passage


54


located nearer to the frame part of deflector


9


translates via a bend into a passage


56


oriented vertically upwards, the upper end of which is connected to a suitable pressure/suction source, such as a blower.




As shown in

FIGS. 1 and 2

only one single simultaneously effective tool edge


16


is provided for each working zone or device


1


so that tool engagement is possible on one face only of the corresponding material


3


. The configuration as shown in

FIG. 3

is suitable for providing tool engagement optionally on both faces of the material


3


. For this purpose identical units


18


,


37


are secured separate to the same support flanges


38


′ on both sides of axial plane or axis


45


and adjustable about axis


46


independently of each other as as removable independently of each other. The working faces


16


of these two units spacedly oppose each other symmetrically to plane


45


. Flanks


21


are counter inclined so that their planes


10


are oriented at an obtuse angle in a V-formation to each other. Cheeks


26


,


27


likewise support two separate deflecting faces


15


,


15


′ or identical deflection bodies


17


having separate deflection axes


22


,


23


arranged symmetrically on both sides of an axial plane of positioning axis


25


. In one position this axial plane coincides with plane


45


so that the material


3


is able to pass from deflector


8


to deflector


11


without contact between rolls


17


and tools


18


, i.e. without being deflected in the working zone. By pivoting unit


17


,


26


,


27


in the one direction into the position as shown in

FIG. 3

the material


3


is transferred from the deflection on one guiding face


15


with one material face into bending engagement of the other material face with the one bending face, namely the right-hand face


16


. By pivoting in the opposite direction the material


3


is correspondingly brought into engagement with the other bending edge


16


by the other deflection face


15


′.




Due to pivoting about axis


25


the angle of wrap at the corresponding edge


16


can be varied dynamically and continuously during operation. Thereby the wrap angle at the corresponding deflection face


15


,


15


′ as well as the width of gap


20


are also changed. Gear


32


automatically locks each setting by the inner obstruction of its gear members. Independently of this, this wrap angle and gapwidth can be altered by positioning means


39


. In this respect also the two flanges


38


could be displaced relative to each other in torsional deformation of unit


18


,


37


to achieve differing wrap angles along the length of edge


16


, as is possible by positioning means


40


. However, the dynamic variation is undertaken not with tools


18


but with deflections


17


resulting in a very simple configuration of the suction means


19


. Each passage


51


is connected to one of the connectors


52


. All subdevices


1


are connected to a common longitudinal header passage


54


. The cited ends of the two passages


54


are connected to the common riser passage


56


via the cited bend, configured as a Y-connector. Since the deflectors


17


cannot come into contact with tools


18


or other components of the device


1


even when fully rotated about axis


25


no means for restricting travel such as limit switches are needed. Each tool


18


or the tool edge


16


thereof may also be replaced by a rotating rod, the bearings of which are to be flanged to the support flanges


38


′ or provided on flanges


38


. All components are located freely accessible thus greatly facilitating maintenance or insertion of the material


3


.




As shown in

FIG. 3

on the side of the deflector


17


facing away from tool


18


, namely between deflectors


8


,


17


or


11


,


17


a further material guide


57


may be provided located nearer to deflector


17


. Guide


57


does not deflect during bending but when the material


3


is guided past without contacting bending face


16


or at the most slightestly touching it. For each deflection face


15


,


15


′ material guide


57


comprises a corresponding frame-fixed deflector


58


,


58


′ or cylindrical rod or the like. In one position deflection face


15


forms with deflector


58


a tight passage gap for S-shaped reversing deflection of the material


3


and in the other position for likewise oppositely deflecting in the region of an equal deflector gap between deflection face


15


′ and deflector


58


′. The material passes through the deflection gap in each case without any clamping pressure so that only one material face has deflector contact at any moment. Deflectors


58


,


58


′ are secured to flanges


59


and thus secured adjustable and removable at a support flange


59


′ as already described with respect to flanges


38


. Accordingly, here too, positioning means may be provided corresponding to means


39


,


40


, the deflectors


58


,


58


′ like the deflectors


16


each being located eccentrically to the corresponding positioning axis.




In the embodiment shown in

FIG. 10

the deflectors


17


are provided spacedly downstream of bending faces


16


and deflector


8


is located upstream of faces


16


as shown in FIG.


1


. To engage and disengage passage control mode for non-worked passage of material


3


past the faces


16


the drive


31


is a power of fluid cylinder. Drive cylinder


31


comprises two separate cylinders each separately controllable and rigidly connected to each other in series. The pistons rods face away from each other. Each cylinder can be transposed separately into two end positions so that four stop-limited working strokes, namely that of each individual cylinder and the two working cylinders are achieved. Instead of the deflectors


17


being fixedly mounted to the frame the units


18


,


37


or the supporting flange


38


′ are pivoted about axis


25


of deflector


8


by drive


31


. Thereby each of the two tools


18


too, can optionally be brought into engagement with the material


3


. Fine adjustment of the tool


18


or of its wrap angle is done manually via gearing such as a worm gear.



Claims
  • 1. A setting device for bending layer material defining remote first and second layer faces, said setting device comprising:a stationary base frame; a running path defining a running direction and a cross-sectional running plane, and first and second guide faces for guiding the layer material, said first guide face including a bending face and said second guide face including a deflection face, said first and second guide faces being operationally directly interconnected by the layer material when passing between said first and second guide faces, and wherein dusting means are included for conveying dust away from said running path.
  • 2. The setting device according to claim 1, wherein said dusting means include suction means directly connecting to at least one of said first and second guide faces.
  • 3. A setting device for bending layer material defining remote first and second layer faces, said setting device comprising:a stationary base frame; a running path defining a running direction and a cross-sectional running plane, and first and second guide faces for guiding the layer material, said first guide face including a bending face and said second guide face including a deflection face, said first and second guide faces being operationally directly interconnected by the layer material when passing between said first and second guide faces, said first and second guide faces bounding a gap defining a gap shape for passing the layer material, said gap shape being operationally variable by displacing said first guide face with respect to said second guide face, between said first and second guide faces said gap defining a gap plane, and wherein an air port connects directly to said gap, said air port being positionally displaceable with said bending face and with respect to said deflection face.
  • 4. A setting device for bending layer material defining remote first and second layer faces, said setting device comprising:a stationary base frame; a running path defining a running direction and a cross-sectional running plane, and first and second guide faces for guiding the layer material, said first guide face including a bending face and said second guide face including a deflection face, said first and second guide faces being operationally directly interconnected by the layer material when passing between said first and second guide faces, and a bending body including said bending face and exchangeably mounted on a support rod, wherein said support rod includes a hollow profile including angular internal cross-sections.
  • 5. A setting device for bending layer material defining remote first and second layer faces, said setting device comprising:a stationary base frame; a running path defining a running direction and a cross-sectional running place, and first and second guide faces for guiding the layer material, said first guide face including a bending face and said second guide face including a deflection face, said first and second guide faces being operationally directly interconnected by the layer material when passing between said first and second guide faces, and a bending rod including said bending face, wherein said bending rod includes a fluid duct for operationally passing a fluid.
Priority Claims (1)
Number Date Country Kind
197 13 207 Mar 1997 DE
US Referenced Citations (12)
Number Name Date Kind
2070505 Beck Feb 1937
3649447 Turner Mar 1972
3661703 Shelor May 1972
3772145 Notbohm Nov 1973
4013284 Demetre Mar 1977
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