CA2038750C - Process and apparatus suitable for effecting steel band guidance - Google Patents
Process and apparatus suitable for effecting steel band guidanceInfo
- Publication number
- CA2038750C CA2038750C CA002038750A CA2038750A CA2038750C CA 2038750 C CA2038750 C CA 2038750C CA 002038750 A CA002038750 A CA 002038750A CA 2038750 A CA2038750 A CA 2038750A CA 2038750 C CA2038750 C CA 2038750C
- Authority
- CA
- Canada
- Prior art keywords
- press
- pressure
- bands
- cylinder assemblies
- beams
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 72
- 239000010959 steel Substances 0.000 title claims abstract description 72
- 238000000034 method Methods 0.000 title claims abstract description 35
- 230000000712 assembly Effects 0.000 claims abstract description 43
- 238000000429 assembly Methods 0.000 claims abstract description 43
- 238000003825 pressing Methods 0.000 claims description 37
- 239000000463 material Substances 0.000 claims description 34
- 210000000887 face Anatomy 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 6
- 125000006850 spacer group Chemical group 0.000 claims 5
- 230000013011 mating Effects 0.000 claims 2
- 238000010438 heat treatment Methods 0.000 description 9
- 238000013461 design Methods 0.000 description 4
- 238000006073 displacement reaction Methods 0.000 description 4
- 238000012423 maintenance Methods 0.000 description 3
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 210000003128 head Anatomy 0.000 description 1
- 230000002706 hydrostatic effect Effects 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000011120 plywood Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27N—MANUFACTURE BY DRY PROCESSES OF ARTICLES, WITH OR WITHOUT ORGANIC BINDING AGENTS, MADE FROM PARTICLES OR FIBRES CONSISTING OF WOOD OR OTHER LIGNOCELLULOSIC OR LIKE ORGANIC MATERIAL
- B27N3/00—Manufacture of substantially flat articles, e.g. boards, from particles or fibres
- B27N3/08—Moulding or pressing
- B27N3/20—Moulding or pressing characterised by using platen-presses
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27N—MANUFACTURE BY DRY PROCESSES OF ARTICLES, WITH OR WITHOUT ORGANIC BINDING AGENTS, MADE FROM PARTICLES OR FIBRES CONSISTING OF WOOD OR OTHER LIGNOCELLULOSIC OR LIKE ORGANIC MATERIAL
- B27N3/00—Manufacture of substantially flat articles, e.g. boards, from particles or fibres
- B27N3/08—Moulding or pressing
- B27N3/24—Moulding or pressing characterised by using continuously acting presses having endless belts or chains moved within the compression zone
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B30—PRESSES
- B30B—PRESSES IN GENERAL
- B30B1/00—Presses, using a press ram, characterised by the features of the drive therefor, pressure being transmitted directly, or through simple thrust or tension members only, to the press ram or platen
- B30B1/32—Presses, using a press ram, characterised by the features of the drive therefor, pressure being transmitted directly, or through simple thrust or tension members only, to the press ram or platen by plungers under fluid pressure
- B30B1/323—Presses, using a press ram, characterised by the features of the drive therefor, pressure being transmitted directly, or through simple thrust or tension members only, to the press ram or platen by plungers under fluid pressure using low pressure long stroke opening and closing means, and high pressure short stroke cylinder means
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B30—PRESSES
- B30B—PRESSES IN GENERAL
- B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
- B30B15/04—Frames; Guides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B30—PRESSES
- B30B—PRESSES IN GENERAL
- B30B5/00—Presses characterised by the use of pressing means other than those mentioned in the preceding groups
- B30B5/04—Presses characterised by the use of pressing means other than those mentioned in the preceding groups wherein the pressing means is in the form of an endless band
- B30B5/06—Presses characterised by the use of pressing means other than those mentioned in the preceding groups wherein the pressing means is in the form of an endless band co-operating with another endless band
Abstract
The present invention relates to a process for correcting misalignment of steel bands circulating about a continuously operating press and to a press adapted for such correction of misalignment. The press has a fixed press bed and a movable press top and a pair of endless flexible steel bands circulating around the press bed and the press top and defining a press gap between them having a high pressure zone, a medium pressure zone and a low pressure zone. The press top is flexible, at least in the high pressure zone, the flexing being controlled by piston and cylinder assemblies arranged on opposite longitudinal sides of the press. The bands pass over driven and deflection rollers on opposite sides of the press gap and at least one of the rollers is adjustable so that its axis of rotation can be moved. When realignment of one of the steel bands is required, the short stroke piston and cylinder assemblies are operated on one side of the press to reduce pressure on the band at that side, and then the axis of rotation of the adjustable roller is moved to cause the desired realignment. In this way, stretching and deformation of the band during realignment can be avoided.
Description
2~38750 ',~ 1 Process and Apparatus Suitable for Effecting Steel Band Guidance The present invention relates to a process and to an apparatus suitable for guiding the steel band of a continuously-operating press along the longitudinal axis of the press.
Continuously-operating presses normally comprise a press bed and a press top which can be moved towards or away from each other and define a press gap between them through which a feedstock material is drawn and compressed by a pair of endless flexible steel bands which recirculate about the press bed and the press top. The steel bands normally pass over drive drums and deflection drums at the inlet and outlet of the press gap. Heater plates are generally provided on the opposed faces of the press bed and the press top for the purpose of heating the feedstock material as it is drawn through the press gap and the steel bands roll on roller rods, whose axes run transversely to the direction of movement of the steel bands, provided between the steel bands and the press top or the press bed.
Presses of this kind are used to form particle board, fibre board, plywood sheets and compressed sheets of other particulate feedstock material.
In such prior art heating plate presses, the press top and the press bed usually comprise merely webbed plates and cross ribs serving to connect the latter (e.g. as in DE-OS 31 49 243 and DE-OS 37 02 9g5). A number of such webbed plates, which are further strengthened with cross ribbing are welded together into single beams that are first grouped together and then arranged in series. The attachment of heating plates to the beam structure completes an assembly whose length 203~75~
corresponds effectively to that of press top and press bed and thus also to the length of the heating plate press itself.
Attachments or protrusions that extend outwardly left and right from the webbed plates provide contact surfaces for the press columns, which form part of the frame, to raise and lower the press top. In conventional systems, furthermore, short-stroke pressing cylinder-and-piston assemblies are arranged between the upper crossheads and the attachments to the press top.
Practical use of continuously-operating presses employing either hydrostatic or rolling support involving roller rods has demonstrated that the all-important control of steel band travel becomes problematic in longer presses that are employed for the purpose of achieving higher product throughput.
Control of the steel band running path becomes difficult in presses whose length exceeds 28 m. For example:
a) slight disruptions in the lubrication of the steel bands or roller rods, or b) uneven process material density distributions, may negatively affect online control, rendering impossible the return of the steel bands to their medial alignment by the angular displacement of the axes of the drive and deflection rollers.
The steel bands are, in the zone of the heating plate, and especially in the first third of the high pressure zone in the press gap, locked in position as in a vise. When the roller axis is displaced through its displacement angle, the steel band, not being locked in position in this region, undergoes partially greater elongation than in its fixed region. The same phenomenon occurs in the vicinity of the exit-side roller. The relationship between the length of the fixed section of the steel band in the high-pressure zone of presses of greater length and the section of such band in entry-side and exit side zones becomes increasingly disadvantageous. In order, therefore, to avoid one-side overstretching of the steel bands during adjustment of steel band travel, the press must be shut down with obvious : ~ 3 ~ 7 ~ ~
disadvantages.
An object of the present invention is, therefore, to provide a process which enables, during operation, the steel band to be adjusted relative to the longitudinal axis of the press without becoming overstretched on one side.
Another object of the present invention is to provide an apparatus whereby the above-mentioned process can be implemented.
According to one aspect of the invention there is provided a method of guiding first and second endless steel bands about a longitudinal axis of a continuously-operating press for the manufacture of pressed boards, the continuously-operating press having short-stroke piston and cylinder assemblies and multiple pressure regions of varying pressure and said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said method comprising the steps of (A) guiding said first and second bands, via driving rollers and deflection rollers, around a press top and a pressing bed, respectively; (B) supporting said steel bands, with an adjustable press gap formed therebetween, on a plurality of co-rotating steel rods which are guided, with their axes of rotation extending transversely to the direction of travel of said bands; (C) altering a position of said press top so that a part of said press top is inclined at an angle ~ relative to a horizontal plane, said altering step comprising the steps of (i) temporarily relieving pressing in said short-stroke piston and cylinder assemblies which are located on one longitudinal side of a high-pressure region of said press, and then (ii) applying a pressure which opposes the pressure imposed by said short-stroke piston and cylinder assemblies and which overcomes the pressures imposed by those of said piston and cylinder assemblies which are located on said one longitudinal side, thereby adjusting the position of said one longitudinal side so that said part of said press top is inclined at said angle ~; and (D) altering an angle of at least one of said rollers in a first direction through an angle ~.
7 ~ ~
: ~ 4 According to another aspect of the invention there is provided a method of guiding first and second endless steel bands about a longitudinal axis of a continuously-operating press for the manufacture of pressed boards, the continuously-operating press having short-stroke piston and cylinder assemblies and having multiple pressure regions of varying pressure, and said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said method comprising the steps of (A) guiding said first and second bands, via driving rollers and deflection rollers, around a press top and a press bed, respectively; (B) altering a position of said press top so that a part of said press top is inclined at an angle ~ relative to a horizontal plane, said altering step comprising the steps of (i) temporarily relieving pressure in said short-stroke piston and cylinder assemblies which are located on one longitudinal side of a high-pressure region of said press, and then (ii) applying a pressure which opposes the pressure imposed by said short-stroke piston and cylinder assemblies and which overcomes the pressures imposed by those of said piston and cylinder assemblies which are located on said one longitudinal side, thereby adjusting the height of said one longitudinal side so that said part of said press top is inclined at said angle ~; and C) altering an axis of at least one of said rollers through an angle ~.
According to yet another aspect of the invention there is provided a method of guiding first and second endless steel bands about a longitudinal axis of a continuously-operating press for the manufacture of pressed boards, the continuously-operating press having short-stroke piston and cylinder assemblies and multiple pressure regions of varying pressure and said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said method comprising the steps of (A) guiding said first and second bands, via driving rollers and deflection rollers, around a press top and a press bed, respectively; (B) supporting said steel bands, with an adjustable press gap B
7 ~ ~
4a formed therebetween, on a plurality of co-rotating steel rods which are guided, with their axes of rotation extending transversely to the direction of travel of said bands; and (C) altering a position of said press top; and a part of said press top is inclined at an angle ~ relative to a horizontal plane; and (D) applying a varying pressure profile to the material to be pressed via the inclined press top along a direction transverse to the longitudinal axis; and (E) altering an angle of at least one of said rollers through an angle ~ at least at a beginning of step (C).
According to yet another aspect of the invention there is provided a device for guiding first and second steel bands about a longitudinal axis of a continuously-operating press having a high-pressure region, said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said device comprising: (A) a press bed; (B) a press top composed of a plurality of beams, at least two of which are located in said high-pressure region;(C) connectors which connect the beams of said high-pressure region while allowing said beams to flex with respect to one another in the direction of a pressing plane of said press; (D) driving rollers and deflection rollers which guide said first and second bands around said press top and said press bed, respectively, the axis of at least one of said rollers being alterable through an angle ~; (E) a plurality of co-rotating steel rods which are guided with their axes of rotation extending transversely to the direction of travel of said bands, said steel rods supporting said first and second steel bands with an adjustable press gap formed therebetween;
(F) press pillars which support said press top, each of said uprights comprising a plurality of removable drawbars and parallel upper and lower crossheads which are connected to eyes of said drawbars via one of pins and bolts; and (G) short-stroke piston and cylinder assemblies which are located on opposed longitudinal sides of said press and which apply said pressing pressure to said steel bands, wherein the pressure in at least one of said assemblies on one of said ' ~ a~
4b longitudinal sides of said press is relieved when the axis of said at least one roller is altered.
According to yet another aspect of the invention there is provided a continuously-operating press having a high pressure region, said press comprising (A) a press bed; (B) a press top composed of a plurality of beams, at least two of which are located in said high-pressure region; (C) connectors which connect the beams of said high-pressure region while allowing said beams to flex with respect to one another in the direction of a pressing plane of said press; (D) first and second steel bands which transmit pressure to a material to be pressed and draw said material through said press, said bands running around said press top and said press bed, respectively; (E) press pillars which support said press top, each of said pillars comprising a plurality of removable drawbars and parallel upper and lower crossheads which are connected to eyes of said drawbars via one of pins and bolts;
(F) means for raising a first longitudinal side of a portion of said press ram which is located in said high-pressure region with respect to a second longitudinal side so that said first longitudinal side is inclined with respect to said second longitudinal side by an angle ~; and (G) short-stroke piston and cylinder assemblies which are located on said first and second longitudinal sides of said press and which apply said pressing force to said steel bands, the pressure in at least one of said cylinders on said first longitudinal side of said press being relieved when said one longitudinal side is ralsed.
According to yet another aspect of the invention there is provided a device for guiding first and second steel bands about a longitudinal axis of a continuously-operating press having a high-pressure region, said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said device comprising: (A) a press bed; (B) a press top composed of a plurality of beams, at least two of which are located in said high-pressure region; (C) connectors which connect the beams of said 4c high-pressure region while allowing said beams to flex with respect to one another in the direction of a pressing plane of said press; (D) driving rollers and deflection rollers which guide said first and second bands around said press top and said press bed, respectively, the axis of at least one of said rollers being alterable through an angle ~; (E) a plurality of co-rotating steel rods which are guided with their axes of rotation extending transversely to the direction of travel of said bands, said steel rods supporting said first and second steel bands with an adjustable press gap formed therebetween;
(F) press pillars which support said press top, each of said pillars comprising a plurality of removable drawbars and parallel upper and lower crossheads which are connected to eyes of said drawbars via one of pins and bolts; and (G) first short-stroke piston and cylinder assemblies which are located on opposed longitudinal sides of said press top and which apply pressure along a longitudinal direction of said press top creating a first variable pressure profile in said longitudinal direction.
The present invention enables the steel bands of both the press top and/or the press bed to be adjusted during press operation relative to the medial longitudinal axis of the press with the aid of displacement cylinder-piston assemblies that are located near the drive and/or deflection roller axes without either damaging the steel bands or producing one-sided elongation therein. A precondition to this arrangement is the resilient design of the press top in the high pressure and if need be, mid-pressure zone, of the roller gap, which enables first a reduction in the pressure load on the short-stroke pressure cylinders that are located on the longitudinal side n questlon.
The above-mentioned process is effected by means of an arrangement wherein the individual beams that are located in the high-pressure zone and, if need be, in the mid-pressure zone, move to a limited extent vertically relative to each other under upward counter-pressure from the material to be pressed during depressurization of the appropriate short-D
4d stroke cylinders and wherein furthermore the press top in the lower-pressure zone and, if need be along a section of the mid-pressure zone, both remain in the horizontal attitude and maintain effective pressing force.
The development of non-symmetrical pressure profile in the press top together with the assumption of a slanted _ 5 orientation about an angle ~ is assisted by an arrangement in which the suspension of the press top over the press bed via the press columns is assisted by means of freely movable drawbars.
A further advantage of the present invention is that, for the purpose of per~orming maintenance tasks in the press, e.g.
in the region of one 4-5m long heating plate that is to be replaced, the groups of drawbars located in this region can be swung outwardly far enough so as to permit access to the area of the press requiring maintenance.
The invention is described in more detail below with reference to the accompanying drawings, in which:
Fig. 1 is a front view of a proposed press along a section A-B, as shown in Fig. 3 minus steel bands, drive and deflection drums;
Fig. 2 shows the press of Fig. 1, in schematic form, from entry-side to middle;
Fig. 3 is a plan view of the press shown in Fig. 2;
Figs. 4, 5 and 6 show the elastic construction of the individual beams relative to each other; and Fig. 7 is a top schematic vièw of the proposed press.
Continuously-operating press 1 comprises, as Figs. 1 to 7 indicate, an immobile press bed 2, a movable press top 3 and press frame pillars 36 that are disposed along both longitudinal sides of press bed 2. Rigidly attached to the press as extensions to the press are side plates 21 that serve to anchor and bear the shafts of drive rollers 37, deflection rollers 9 and 10 as well as to house adjustment cylinder-piston assemblies 17, which are arranged along axes IV-IV and V-V. Press top 3 and press bed 2 comprise only webbed plates and cross ribbing serving to connect the latter. A plurality of webbed plates are, together with the cross ribs, welded together into single beams 8, which, when arranged in series and fitted with heating plates 14, correspond to the length "1" of press top 3 and press bed 2, and thus also to the integral length of the heated plate press 1 itself.
The extensions of the webbed plates that project out to the left and right provide a bearing surface for the press frame pillars 36 to raise and lower press top 3, whereby short-stroke pressing cylinder-piston assemblies 15 and 16 are arranged between upper crossheads 23 and the extensions of press top 3.
Each press frame pillar 36 comprises two drawbars 13, upper crosshead 23 and lower cross head 22. Attached on both left and right hand sides of upper and lower crossheads 23 and 22 are pins or bolts 26 that extend outwardly on each side.
Crossheads 22 and 23 are connected together by means of drawbars 13 that are suspended from pins 26 or bolts 26 that fit into eyes 27 of such drawbars.
Fitted to crosshead 22 or 23 are bolts 26 that can be removed whenever required. The overall design of press 1 provides that a majority of drawbars 13 (see Fig. 3) may remain standing vertically to the left and right of a group of outwardly swung drawbars 13 and are thus able to freely support press top 3 and so permit replacement of e.g. heating plates 14 and maintenance or repair to other components in the region of the outwardly swung group of drawbars.
Figs. l and 7 furthermore show the manner by which press top 3 can be raised up on one side through angle ~ along one longitudinal side I-I or II-II of press top 3 inside elastic region "e", which encompasses preferably high pressure zone HD
and up to half of mid-pressure zone MD. The aim of this procedure is to reduce the pressure bearing on steel bands 5 and 6 for instance during disturbances in press operation which might necessitate the realignment in the vicinity of the forward roller of the steel band with the medial longitudinal axis III-III of press 1. The procedure of decreasing the load on the short-stroke pressure cylinders 7 and 15 located inside press frame pillar 36 can be so regulated, that short-stroke pressure cylinders 7 and 15, which are disposed along each of individual beams 8 across longitudinal axis III-III, are loaded with steadily decreasing pressing force from opposing longitudinal side I-I or II-II to the outer longitudinal side II-II or I-I that is being adjusted.
20~1875~
As shown in Fig. 2, the elastic region "e" of press top 3, in systems operating with very high pressing forces, can encompass the entire mid-pressure zone MD.
The precondition for the elasticity of press top 3 is, however, the resilient method by which the individual beams 8 are connected together, enabling the creation of an asymmetric pressure profile in high pressure zone HD and, if required, in mid-pressure zone MD. Figures 4,5 and 6 show three alternative approaches to the elastic design of press top 3 in the different regions. In Fig. 4, steel springs 28 are provided between individual beams 8, which, under the application of counter pressure from an element such as a leaf spring, are caused to deform. The arrow and the broken lines indicate in all three examples the vertical range of adjustment possible amongst individual beams 8. Instead of resilient steel members, the configuration shown in Fig.5 provides that elastic rubber blocks 33 be disposed between spacing elements 39 and 40, the individual beams 8 being connected together by means of bolts 29, which also deform elastically during vertical motion. The individual beams 8 shown in Fig. 6 are also connected together by means of bolts 29 and interlock along slip faces 30. Spacing elements 31 and 32 that are installed so as to leave free spaces 34 and 35 provide for hydraulically actuated adjustment of the individual bèams 8 relative to each other. Spacing element 31 interlocks with the left-hand individual beam 8, and spacing element 32 interlocks with the right-hand individual beam.
Free spaces 34 and 35 comprise approx. O to 1,2 mm (to a maximum of 2,4mm). The freedom of motion afforded by such free spaces corresponds to the allowable elastic deformability of bolts 29 within the admissible tension range and also provides a means of relieving pressure in order to allow repositioning of steel bands 5 and 6, without causing one-sided over expansion of the steel band.
The proposed elastic design of one part of press top 3 permits the temporary development upon either the left or the right side in the process direction of a pressure profile or path of motion profile that effects overall adjustment needs.
In other words, press top 3 is shifted from its normally horizontal attitude into a slanted attitude by means of short-stroke pressure cylinders 15 that are installed on the outside of the press. Press top 3 is, in the elastic region "e" of high pressure zone HD and, if required, along up to half of mid-pressure region MD, as viewed from the entry side looking toward the exit of the press, moved temporarily through angle ~. Such upward tilting motion produces, on the left or right-hand side, depending on whichever is selected, i.e. alonglongitudinal side I-I or II-II, a reduction in pressure, so that steel bands 5 and/or 6 can be moved by means of adjustment cylinders 17 through angle $ back into alignment with longitudinal medial axis III-III. Both control procedures must be coordinated in such a manner that the displacement of the roller axes IV-IV and/or V-V begins only after pressure relief on short-stroke pressure cylinders 7 and 15 has either been completed or at least begun. The process by means of which the press top is moved into a slanted attitude through the angle ~ with the aid of short-stroke pressure cylinders 15 can be supported by the positioning to the left or right of multipot cylinders 7, in each of which the cylinder pressures can be individually adjusted. As soon as the steel band has been realigned with the longitudinal medial axis of the press, press top 3 is guided back into the horizontal attitude, at which point angle ~ has a value of zero. The above-described procedure permits the continuously-operating press in the second half of the medium-pressure zone MD and the low pressure zone ND to regain its horizontal disposition and to allow such press to be employed in a calibrating role.
Because the elastic press top can move through angle ~
across high pressure region HD, the particulate pressing mass, can, after steel band adjustment, undergo the same degree of continuous compression while traversing the region of the entry-side angle as was the case prior to ad~ustment of the steel band.
B
2038~50 _,.~ g Fig. 2 also indicates the manner in which deflection rollers 9 and lO form entry gap 4 and in which roller rods 11, which travel together with steel bands 5 and 6 about press bed 2 and press top 3, and being carried along by means of guide chains 12, bear upon press bed 2 and press top 3. In other words, circulating roller rods 11 are arranged between heating plates 14 and steel bands 5 and 6 in such a way as to be able to roll with the latter.
Continuously-operating presses normally comprise a press bed and a press top which can be moved towards or away from each other and define a press gap between them through which a feedstock material is drawn and compressed by a pair of endless flexible steel bands which recirculate about the press bed and the press top. The steel bands normally pass over drive drums and deflection drums at the inlet and outlet of the press gap. Heater plates are generally provided on the opposed faces of the press bed and the press top for the purpose of heating the feedstock material as it is drawn through the press gap and the steel bands roll on roller rods, whose axes run transversely to the direction of movement of the steel bands, provided between the steel bands and the press top or the press bed.
Presses of this kind are used to form particle board, fibre board, plywood sheets and compressed sheets of other particulate feedstock material.
In such prior art heating plate presses, the press top and the press bed usually comprise merely webbed plates and cross ribs serving to connect the latter (e.g. as in DE-OS 31 49 243 and DE-OS 37 02 9g5). A number of such webbed plates, which are further strengthened with cross ribbing are welded together into single beams that are first grouped together and then arranged in series. The attachment of heating plates to the beam structure completes an assembly whose length 203~75~
corresponds effectively to that of press top and press bed and thus also to the length of the heating plate press itself.
Attachments or protrusions that extend outwardly left and right from the webbed plates provide contact surfaces for the press columns, which form part of the frame, to raise and lower the press top. In conventional systems, furthermore, short-stroke pressing cylinder-and-piston assemblies are arranged between the upper crossheads and the attachments to the press top.
Practical use of continuously-operating presses employing either hydrostatic or rolling support involving roller rods has demonstrated that the all-important control of steel band travel becomes problematic in longer presses that are employed for the purpose of achieving higher product throughput.
Control of the steel band running path becomes difficult in presses whose length exceeds 28 m. For example:
a) slight disruptions in the lubrication of the steel bands or roller rods, or b) uneven process material density distributions, may negatively affect online control, rendering impossible the return of the steel bands to their medial alignment by the angular displacement of the axes of the drive and deflection rollers.
The steel bands are, in the zone of the heating plate, and especially in the first third of the high pressure zone in the press gap, locked in position as in a vise. When the roller axis is displaced through its displacement angle, the steel band, not being locked in position in this region, undergoes partially greater elongation than in its fixed region. The same phenomenon occurs in the vicinity of the exit-side roller. The relationship between the length of the fixed section of the steel band in the high-pressure zone of presses of greater length and the section of such band in entry-side and exit side zones becomes increasingly disadvantageous. In order, therefore, to avoid one-side overstretching of the steel bands during adjustment of steel band travel, the press must be shut down with obvious : ~ 3 ~ 7 ~ ~
disadvantages.
An object of the present invention is, therefore, to provide a process which enables, during operation, the steel band to be adjusted relative to the longitudinal axis of the press without becoming overstretched on one side.
Another object of the present invention is to provide an apparatus whereby the above-mentioned process can be implemented.
According to one aspect of the invention there is provided a method of guiding first and second endless steel bands about a longitudinal axis of a continuously-operating press for the manufacture of pressed boards, the continuously-operating press having short-stroke piston and cylinder assemblies and multiple pressure regions of varying pressure and said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said method comprising the steps of (A) guiding said first and second bands, via driving rollers and deflection rollers, around a press top and a pressing bed, respectively; (B) supporting said steel bands, with an adjustable press gap formed therebetween, on a plurality of co-rotating steel rods which are guided, with their axes of rotation extending transversely to the direction of travel of said bands; (C) altering a position of said press top so that a part of said press top is inclined at an angle ~ relative to a horizontal plane, said altering step comprising the steps of (i) temporarily relieving pressing in said short-stroke piston and cylinder assemblies which are located on one longitudinal side of a high-pressure region of said press, and then (ii) applying a pressure which opposes the pressure imposed by said short-stroke piston and cylinder assemblies and which overcomes the pressures imposed by those of said piston and cylinder assemblies which are located on said one longitudinal side, thereby adjusting the position of said one longitudinal side so that said part of said press top is inclined at said angle ~; and (D) altering an angle of at least one of said rollers in a first direction through an angle ~.
7 ~ ~
: ~ 4 According to another aspect of the invention there is provided a method of guiding first and second endless steel bands about a longitudinal axis of a continuously-operating press for the manufacture of pressed boards, the continuously-operating press having short-stroke piston and cylinder assemblies and having multiple pressure regions of varying pressure, and said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said method comprising the steps of (A) guiding said first and second bands, via driving rollers and deflection rollers, around a press top and a press bed, respectively; (B) altering a position of said press top so that a part of said press top is inclined at an angle ~ relative to a horizontal plane, said altering step comprising the steps of (i) temporarily relieving pressure in said short-stroke piston and cylinder assemblies which are located on one longitudinal side of a high-pressure region of said press, and then (ii) applying a pressure which opposes the pressure imposed by said short-stroke piston and cylinder assemblies and which overcomes the pressures imposed by those of said piston and cylinder assemblies which are located on said one longitudinal side, thereby adjusting the height of said one longitudinal side so that said part of said press top is inclined at said angle ~; and C) altering an axis of at least one of said rollers through an angle ~.
According to yet another aspect of the invention there is provided a method of guiding first and second endless steel bands about a longitudinal axis of a continuously-operating press for the manufacture of pressed boards, the continuously-operating press having short-stroke piston and cylinder assemblies and multiple pressure regions of varying pressure and said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said method comprising the steps of (A) guiding said first and second bands, via driving rollers and deflection rollers, around a press top and a press bed, respectively; (B) supporting said steel bands, with an adjustable press gap B
7 ~ ~
4a formed therebetween, on a plurality of co-rotating steel rods which are guided, with their axes of rotation extending transversely to the direction of travel of said bands; and (C) altering a position of said press top; and a part of said press top is inclined at an angle ~ relative to a horizontal plane; and (D) applying a varying pressure profile to the material to be pressed via the inclined press top along a direction transverse to the longitudinal axis; and (E) altering an angle of at least one of said rollers through an angle ~ at least at a beginning of step (C).
According to yet another aspect of the invention there is provided a device for guiding first and second steel bands about a longitudinal axis of a continuously-operating press having a high-pressure region, said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said device comprising: (A) a press bed; (B) a press top composed of a plurality of beams, at least two of which are located in said high-pressure region;(C) connectors which connect the beams of said high-pressure region while allowing said beams to flex with respect to one another in the direction of a pressing plane of said press; (D) driving rollers and deflection rollers which guide said first and second bands around said press top and said press bed, respectively, the axis of at least one of said rollers being alterable through an angle ~; (E) a plurality of co-rotating steel rods which are guided with their axes of rotation extending transversely to the direction of travel of said bands, said steel rods supporting said first and second steel bands with an adjustable press gap formed therebetween;
(F) press pillars which support said press top, each of said uprights comprising a plurality of removable drawbars and parallel upper and lower crossheads which are connected to eyes of said drawbars via one of pins and bolts; and (G) short-stroke piston and cylinder assemblies which are located on opposed longitudinal sides of said press and which apply said pressing pressure to said steel bands, wherein the pressure in at least one of said assemblies on one of said ' ~ a~
4b longitudinal sides of said press is relieved when the axis of said at least one roller is altered.
According to yet another aspect of the invention there is provided a continuously-operating press having a high pressure region, said press comprising (A) a press bed; (B) a press top composed of a plurality of beams, at least two of which are located in said high-pressure region; (C) connectors which connect the beams of said high-pressure region while allowing said beams to flex with respect to one another in the direction of a pressing plane of said press; (D) first and second steel bands which transmit pressure to a material to be pressed and draw said material through said press, said bands running around said press top and said press bed, respectively; (E) press pillars which support said press top, each of said pillars comprising a plurality of removable drawbars and parallel upper and lower crossheads which are connected to eyes of said drawbars via one of pins and bolts;
(F) means for raising a first longitudinal side of a portion of said press ram which is located in said high-pressure region with respect to a second longitudinal side so that said first longitudinal side is inclined with respect to said second longitudinal side by an angle ~; and (G) short-stroke piston and cylinder assemblies which are located on said first and second longitudinal sides of said press and which apply said pressing force to said steel bands, the pressure in at least one of said cylinders on said first longitudinal side of said press being relieved when said one longitudinal side is ralsed.
According to yet another aspect of the invention there is provided a device for guiding first and second steel bands about a longitudinal axis of a continuously-operating press having a high-pressure region, said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said device comprising: (A) a press bed; (B) a press top composed of a plurality of beams, at least two of which are located in said high-pressure region; (C) connectors which connect the beams of said 4c high-pressure region while allowing said beams to flex with respect to one another in the direction of a pressing plane of said press; (D) driving rollers and deflection rollers which guide said first and second bands around said press top and said press bed, respectively, the axis of at least one of said rollers being alterable through an angle ~; (E) a plurality of co-rotating steel rods which are guided with their axes of rotation extending transversely to the direction of travel of said bands, said steel rods supporting said first and second steel bands with an adjustable press gap formed therebetween;
(F) press pillars which support said press top, each of said pillars comprising a plurality of removable drawbars and parallel upper and lower crossheads which are connected to eyes of said drawbars via one of pins and bolts; and (G) first short-stroke piston and cylinder assemblies which are located on opposed longitudinal sides of said press top and which apply pressure along a longitudinal direction of said press top creating a first variable pressure profile in said longitudinal direction.
The present invention enables the steel bands of both the press top and/or the press bed to be adjusted during press operation relative to the medial longitudinal axis of the press with the aid of displacement cylinder-piston assemblies that are located near the drive and/or deflection roller axes without either damaging the steel bands or producing one-sided elongation therein. A precondition to this arrangement is the resilient design of the press top in the high pressure and if need be, mid-pressure zone, of the roller gap, which enables first a reduction in the pressure load on the short-stroke pressure cylinders that are located on the longitudinal side n questlon.
The above-mentioned process is effected by means of an arrangement wherein the individual beams that are located in the high-pressure zone and, if need be, in the mid-pressure zone, move to a limited extent vertically relative to each other under upward counter-pressure from the material to be pressed during depressurization of the appropriate short-D
4d stroke cylinders and wherein furthermore the press top in the lower-pressure zone and, if need be along a section of the mid-pressure zone, both remain in the horizontal attitude and maintain effective pressing force.
The development of non-symmetrical pressure profile in the press top together with the assumption of a slanted _ 5 orientation about an angle ~ is assisted by an arrangement in which the suspension of the press top over the press bed via the press columns is assisted by means of freely movable drawbars.
A further advantage of the present invention is that, for the purpose of per~orming maintenance tasks in the press, e.g.
in the region of one 4-5m long heating plate that is to be replaced, the groups of drawbars located in this region can be swung outwardly far enough so as to permit access to the area of the press requiring maintenance.
The invention is described in more detail below with reference to the accompanying drawings, in which:
Fig. 1 is a front view of a proposed press along a section A-B, as shown in Fig. 3 minus steel bands, drive and deflection drums;
Fig. 2 shows the press of Fig. 1, in schematic form, from entry-side to middle;
Fig. 3 is a plan view of the press shown in Fig. 2;
Figs. 4, 5 and 6 show the elastic construction of the individual beams relative to each other; and Fig. 7 is a top schematic vièw of the proposed press.
Continuously-operating press 1 comprises, as Figs. 1 to 7 indicate, an immobile press bed 2, a movable press top 3 and press frame pillars 36 that are disposed along both longitudinal sides of press bed 2. Rigidly attached to the press as extensions to the press are side plates 21 that serve to anchor and bear the shafts of drive rollers 37, deflection rollers 9 and 10 as well as to house adjustment cylinder-piston assemblies 17, which are arranged along axes IV-IV and V-V. Press top 3 and press bed 2 comprise only webbed plates and cross ribbing serving to connect the latter. A plurality of webbed plates are, together with the cross ribs, welded together into single beams 8, which, when arranged in series and fitted with heating plates 14, correspond to the length "1" of press top 3 and press bed 2, and thus also to the integral length of the heated plate press 1 itself.
The extensions of the webbed plates that project out to the left and right provide a bearing surface for the press frame pillars 36 to raise and lower press top 3, whereby short-stroke pressing cylinder-piston assemblies 15 and 16 are arranged between upper crossheads 23 and the extensions of press top 3.
Each press frame pillar 36 comprises two drawbars 13, upper crosshead 23 and lower cross head 22. Attached on both left and right hand sides of upper and lower crossheads 23 and 22 are pins or bolts 26 that extend outwardly on each side.
Crossheads 22 and 23 are connected together by means of drawbars 13 that are suspended from pins 26 or bolts 26 that fit into eyes 27 of such drawbars.
Fitted to crosshead 22 or 23 are bolts 26 that can be removed whenever required. The overall design of press 1 provides that a majority of drawbars 13 (see Fig. 3) may remain standing vertically to the left and right of a group of outwardly swung drawbars 13 and are thus able to freely support press top 3 and so permit replacement of e.g. heating plates 14 and maintenance or repair to other components in the region of the outwardly swung group of drawbars.
Figs. l and 7 furthermore show the manner by which press top 3 can be raised up on one side through angle ~ along one longitudinal side I-I or II-II of press top 3 inside elastic region "e", which encompasses preferably high pressure zone HD
and up to half of mid-pressure zone MD. The aim of this procedure is to reduce the pressure bearing on steel bands 5 and 6 for instance during disturbances in press operation which might necessitate the realignment in the vicinity of the forward roller of the steel band with the medial longitudinal axis III-III of press 1. The procedure of decreasing the load on the short-stroke pressure cylinders 7 and 15 located inside press frame pillar 36 can be so regulated, that short-stroke pressure cylinders 7 and 15, which are disposed along each of individual beams 8 across longitudinal axis III-III, are loaded with steadily decreasing pressing force from opposing longitudinal side I-I or II-II to the outer longitudinal side II-II or I-I that is being adjusted.
20~1875~
As shown in Fig. 2, the elastic region "e" of press top 3, in systems operating with very high pressing forces, can encompass the entire mid-pressure zone MD.
The precondition for the elasticity of press top 3 is, however, the resilient method by which the individual beams 8 are connected together, enabling the creation of an asymmetric pressure profile in high pressure zone HD and, if required, in mid-pressure zone MD. Figures 4,5 and 6 show three alternative approaches to the elastic design of press top 3 in the different regions. In Fig. 4, steel springs 28 are provided between individual beams 8, which, under the application of counter pressure from an element such as a leaf spring, are caused to deform. The arrow and the broken lines indicate in all three examples the vertical range of adjustment possible amongst individual beams 8. Instead of resilient steel members, the configuration shown in Fig.5 provides that elastic rubber blocks 33 be disposed between spacing elements 39 and 40, the individual beams 8 being connected together by means of bolts 29, which also deform elastically during vertical motion. The individual beams 8 shown in Fig. 6 are also connected together by means of bolts 29 and interlock along slip faces 30. Spacing elements 31 and 32 that are installed so as to leave free spaces 34 and 35 provide for hydraulically actuated adjustment of the individual bèams 8 relative to each other. Spacing element 31 interlocks with the left-hand individual beam 8, and spacing element 32 interlocks with the right-hand individual beam.
Free spaces 34 and 35 comprise approx. O to 1,2 mm (to a maximum of 2,4mm). The freedom of motion afforded by such free spaces corresponds to the allowable elastic deformability of bolts 29 within the admissible tension range and also provides a means of relieving pressure in order to allow repositioning of steel bands 5 and 6, without causing one-sided over expansion of the steel band.
The proposed elastic design of one part of press top 3 permits the temporary development upon either the left or the right side in the process direction of a pressure profile or path of motion profile that effects overall adjustment needs.
In other words, press top 3 is shifted from its normally horizontal attitude into a slanted attitude by means of short-stroke pressure cylinders 15 that are installed on the outside of the press. Press top 3 is, in the elastic region "e" of high pressure zone HD and, if required, along up to half of mid-pressure region MD, as viewed from the entry side looking toward the exit of the press, moved temporarily through angle ~. Such upward tilting motion produces, on the left or right-hand side, depending on whichever is selected, i.e. alonglongitudinal side I-I or II-II, a reduction in pressure, so that steel bands 5 and/or 6 can be moved by means of adjustment cylinders 17 through angle $ back into alignment with longitudinal medial axis III-III. Both control procedures must be coordinated in such a manner that the displacement of the roller axes IV-IV and/or V-V begins only after pressure relief on short-stroke pressure cylinders 7 and 15 has either been completed or at least begun. The process by means of which the press top is moved into a slanted attitude through the angle ~ with the aid of short-stroke pressure cylinders 15 can be supported by the positioning to the left or right of multipot cylinders 7, in each of which the cylinder pressures can be individually adjusted. As soon as the steel band has been realigned with the longitudinal medial axis of the press, press top 3 is guided back into the horizontal attitude, at which point angle ~ has a value of zero. The above-described procedure permits the continuously-operating press in the second half of the medium-pressure zone MD and the low pressure zone ND to regain its horizontal disposition and to allow such press to be employed in a calibrating role.
Because the elastic press top can move through angle ~
across high pressure region HD, the particulate pressing mass, can, after steel band adjustment, undergo the same degree of continuous compression while traversing the region of the entry-side angle as was the case prior to ad~ustment of the steel band.
B
2038~50 _,.~ g Fig. 2 also indicates the manner in which deflection rollers 9 and lO form entry gap 4 and in which roller rods 11, which travel together with steel bands 5 and 6 about press bed 2 and press top 3, and being carried along by means of guide chains 12, bear upon press bed 2 and press top 3. In other words, circulating roller rods 11 are arranged between heating plates 14 and steel bands 5 and 6 in such a way as to be able to roll with the latter.
Claims (25)
1. A method of guiding first and second endless steel bands about a longitudinal axis of a continuously-operating press for the manufacture of pressed boards, the continuously-operating press having short-stroke piston and cylinder assemblies and multiple pressure regions of varying pressure and said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said method comprising the steps of:
(A) guiding said first and second bands, via driving rollers and deflection rollers, around a press top and a pressing bed, respectively;
(B) supporting said steel bands, with an adjustable press gap formed therebetween, on a plurality of co-rotating steel rods which are guided, with their axes of rotation extending transversely to the direction of travel of said bands;
(C) altering a position of said press top so that a part of said press top is inclined at an angle .alpha. relative to a horizontal plane, said altering step comprising the steps of:
(i) temporarily relieving pressing in said short-stroke piston and cylinder assemblies which are located on one longitudinal side of a high-pressure region of said press, and then (ii) applying a pressure which opposes the pressure imposed by said short-stroke piston and cylinder assemblies and which overcomes the pressures imposed by those of said piston and cylinder assemblies which are located on said one longitudinal side, thereby adjusting the position of said one longitudinal side so that said part of said press top is inclined at said angle .alpha.; and (D) altering an angle of at least one of said rollers in a first direction through an angle .beta..
(A) guiding said first and second bands, via driving rollers and deflection rollers, around a press top and a pressing bed, respectively;
(B) supporting said steel bands, with an adjustable press gap formed therebetween, on a plurality of co-rotating steel rods which are guided, with their axes of rotation extending transversely to the direction of travel of said bands;
(C) altering a position of said press top so that a part of said press top is inclined at an angle .alpha. relative to a horizontal plane, said altering step comprising the steps of:
(i) temporarily relieving pressing in said short-stroke piston and cylinder assemblies which are located on one longitudinal side of a high-pressure region of said press, and then (ii) applying a pressure which opposes the pressure imposed by said short-stroke piston and cylinder assemblies and which overcomes the pressures imposed by those of said piston and cylinder assemblies which are located on said one longitudinal side, thereby adjusting the position of said one longitudinal side so that said part of said press top is inclined at said angle .alpha.; and (D) altering an angle of at least one of said rollers in a first direction through an angle .beta..
2. The method as claimed in claim 1, wherein said step (i) further comprises the step of temporarily relieving pressure in a short-stroke piston and cylinder assembly located in a medium-pressure region of said press.
3. The method as claimed in claim 1, wherein said press includes an individual beam and a transverse row of short-stroke piston and cylinder assemblies connected to said individual beam and said step (i) further comprises the step of applying pressing pressure to said transverse row of short-stroke piston and cylinder assemblies, which applied pressing pressure progressively increases from a minimum pressure in a first one of said row of piston and cylinder assemblies which is located adjacent said one longitudinal side to a maximum pressure in another one of said row of piston and cylinder assemblies which is located on a longitudinal side opposite said one longitudinal side.
4. A method as claimed in claim 1, wherein said step (ii) comprises the step of applying counter-pressure to said press from a material which is being pressed.
5. A method of guiding first and second endless steel bands about a longitudinal axis of a continuously-operating press for the manufacture of pressed boards, the continuously-operating press having short-stroke piston and cylinder assemblies and having multiple pressure regions of varying pressure, and said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said method comprising the steps of:
(A) guiding said first and second bands, via driving rollers and deflection rollers, around a press top and a press bed, respectively;
(B) altering a position of said press top so that a part of said press top is inclined at an angle .alpha. relative to a horizontal plane, said altering step comprising the steps of:
(i) temporarily relieving pressure in said short-stroke piston and cylinder assemblies which are located on one longitudinal side of a high-pressure region of said press, and then (ii) applying a pressure which opposes the pressure imposed by said short-stroke piston and cylinder assemblies and which overcomes the pressures imposed by those of said piston and cylinder assemblies which are located on said one longitudinal side, thereby adjusting the height of said one longitudinal side so that said part of said press top is inclined at said angle .alpha.; and C) altering an axis of at least one of said rollers through an angle .beta..
(A) guiding said first and second bands, via driving rollers and deflection rollers, around a press top and a press bed, respectively;
(B) altering a position of said press top so that a part of said press top is inclined at an angle .alpha. relative to a horizontal plane, said altering step comprising the steps of:
(i) temporarily relieving pressure in said short-stroke piston and cylinder assemblies which are located on one longitudinal side of a high-pressure region of said press, and then (ii) applying a pressure which opposes the pressure imposed by said short-stroke piston and cylinder assemblies and which overcomes the pressures imposed by those of said piston and cylinder assemblies which are located on said one longitudinal side, thereby adjusting the height of said one longitudinal side so that said part of said press top is inclined at said angle .alpha.; and C) altering an axis of at least one of said rollers through an angle .beta..
6. A method as claimed in claim 5, wherein said step (ii) comprises the step of applying counter-pressure to said press from the material which is being pressed.
7. A method as claimed in claim 5, wherein said step (A) comprises the step of guiding said first and second bands over driving rollers and deflection rollers, and further comprising the step of altering an axis of at least one of said rollers through an angle .beta. via an adjusting piston and cylinder assembly.
8. A method of guiding first and second endless steel bands about a longitudinal axis of a continuously-operating press for the manufacture of pressed boards, the continuously-operating press having short-stroke piston and cylinder assemblies and multiple pressure regions of varying pressure and said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said method comprising the steps of:
(A) guiding said first and second bands, via driving rollers and deflection rollers, around a press top and a press bed, respectively;
(B) supporting said steel bands, with an adjustable press gap formed therebetween, on a plurality of co-rotating steel rods which are guided, with their axes of rotation extending transversely to the direction of travel of said bands; and (C) altering a position of said press top; and a part of said press top is inclined at an angle .alpha. relative to a horizontal plane; and (D) applying a varying pressure profile to the material to be pressed via the inclined press top along a direction transverse to the longitudinal axis; and (E) altering an angle of at least one of said rollers through an angle .beta. at least at a beginning of step (C).
(A) guiding said first and second bands, via driving rollers and deflection rollers, around a press top and a press bed, respectively;
(B) supporting said steel bands, with an adjustable press gap formed therebetween, on a plurality of co-rotating steel rods which are guided, with their axes of rotation extending transversely to the direction of travel of said bands; and (C) altering a position of said press top; and a part of said press top is inclined at an angle .alpha. relative to a horizontal plane; and (D) applying a varying pressure profile to the material to be pressed via the inclined press top along a direction transverse to the longitudinal axis; and (E) altering an angle of at least one of said rollers through an angle .beta. at least at a beginning of step (C).
9. A method as claimed in claim 8, wherein said altering step (C) includes the steps of:
(i) temporarily relieving pressure in short-stroke piston and cylinder assemblies which are located on one longitudinal side of a high-pressure region of said press, and then (ii) applying a pressure which opposes the pressure imposed by said piston and cylinder assemblies and which overcomes the pressures imposed by those of said piston and cylinder assemblies which are located on said one longitudinal side, thereby adjusting the position of said one longitudinal side so that said part of said press top is inclined to said angle .alpha..
(i) temporarily relieving pressure in short-stroke piston and cylinder assemblies which are located on one longitudinal side of a high-pressure region of said press, and then (ii) applying a pressure which opposes the pressure imposed by said piston and cylinder assemblies and which overcomes the pressures imposed by those of said piston and cylinder assemblies which are located on said one longitudinal side, thereby adjusting the position of said one longitudinal side so that said part of said press top is inclined to said angle .alpha..
10. The method as claimed in claim 9, wherein said step (i) further comprises the step of temporarily relieving pressure in short-stroke piston and cylinder assemblies located in a medium-pressure region of said press.
11. The method as claimed in claim 8, wherein said step (i) further comprises the step of applying pressing pressure to a transverse row of short-stroke piston and cylinder assemblies connected to an individual beam of said press, which applied pressing pressure progressively increases from a minimum pressure in a first one of said row of piston and cylinder assemblies which is located adjacent said one longitudinal side to a maximum pressure in another one of said row of piston and cylinder assemblies which is located on a longitudinal side opposite said one longitudinal side.
12. A device for guiding first and second steel bands about a longitudinal axis of a continuously-operating press having a high-pressure region, said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said device comprising:
(A) a press bed;
(B) a press top composed of a plurality of beams, at least two of which are located in said high-pressure region;
(C) connectors which connect the beams of said high-pressure region while allowing said beams to flex with respect to one another in the direction of a pressing plane of said press;
(D) driving rollers and deflection rollers which guide said first and second bands around said press top and said press bed, respectively, the axis of at least one of said rollers being alterable through an angle .beta.;
(E) a plurality of co-rotating steel rods which are guided with their axes of rotation extending transversely to the direction of travel of said bands, said steel rods supporting said first and second steel bands with an adjustable press gap formed therebetween;
(F) press pillars which support said press top, each of said uprights comprising a plurality of removable drawbars and parallel upper and lower crossheads which are connected to eyes of said drawbars via one of pins and bolts; and (G) short-stroke piston and cylinder assemblies which are located on opposed longitudinal sides of said press and which apply said pressing pressure to said steel bands, wherein the pressure in at least one of said assemblies on one of said longitudinal sides of said press is relieved when the axis of said at least one roller is altered.
(A) a press bed;
(B) a press top composed of a plurality of beams, at least two of which are located in said high-pressure region;
(C) connectors which connect the beams of said high-pressure region while allowing said beams to flex with respect to one another in the direction of a pressing plane of said press;
(D) driving rollers and deflection rollers which guide said first and second bands around said press top and said press bed, respectively, the axis of at least one of said rollers being alterable through an angle .beta.;
(E) a plurality of co-rotating steel rods which are guided with their axes of rotation extending transversely to the direction of travel of said bands, said steel rods supporting said first and second steel bands with an adjustable press gap formed therebetween;
(F) press pillars which support said press top, each of said uprights comprising a plurality of removable drawbars and parallel upper and lower crossheads which are connected to eyes of said drawbars via one of pins and bolts; and (G) short-stroke piston and cylinder assemblies which are located on opposed longitudinal sides of said press and which apply said pressing pressure to said steel bands, wherein the pressure in at least one of said assemblies on one of said longitudinal sides of said press is relieved when the axis of said at least one roller is altered.
13. The device as claimed in claim 12, wherein said connectors comprise spring elements.
14. The device as claimed in claim 12, wherein each of said connectors comprise bolts connecting two facing beams and spacing elements having mating faces which have a vertical clearance which allows said faces to slide vertically with respect to one another.
15. The device as claimed in claim 12, wherein said press has a medium-pressure region and wherein at least two of said beams are located in said medium pressure region, and further comprising connectors which connect the beams of said medium-pressure region while allowing said beams to flex with respect to one another in the direction of said pressing plane.
16. The device as claimed in claim 12, where each of said connectors comprises bolts connecting two facing beams, spacers connected to the respective beams, and elastic blocks provided between said spacers.
17. A continuously-operating press having a high pressure region, said press comprising:
(A) a press bed;
(B) a press top composed of a plurality of beams, at least two of which are located in said high-pressure region;
(C) connectors which connect the beams of said high-pressure region while allowing said beams to flex with respect to one another in the direction of a pressing plane of said press;
(D) first and second steel bands which transmit pressure to a material to be pressed and draw said material through said press, said bands running around said press top and said press bed, respectively;
(E) press pillars which support said press top, each of said pillars comprising a plurality of removable drawbars and parallel upper and lower crossheads which are connected to eyes of said drawbars via one of pins and bolts;
(F) means for raising a first longitudinal side of a portion of said press ram which is located in said high-pressure region with respect to a second longitudinal side so that said first longitudinal side is inclined with respect to said second longitudinal side by an angle .alpha.; and (G) short-stroke piston and cylinder assemblies which are located on said first and second longitudinal sides of said press and which apply said pressing force to said steel bands, the pressure in at least one of said cylinders on said first longitudinal side of said press being relieved when said one longitudinal side is raised.
(A) a press bed;
(B) a press top composed of a plurality of beams, at least two of which are located in said high-pressure region;
(C) connectors which connect the beams of said high-pressure region while allowing said beams to flex with respect to one another in the direction of a pressing plane of said press;
(D) first and second steel bands which transmit pressure to a material to be pressed and draw said material through said press, said bands running around said press top and said press bed, respectively;
(E) press pillars which support said press top, each of said pillars comprising a plurality of removable drawbars and parallel upper and lower crossheads which are connected to eyes of said drawbars via one of pins and bolts;
(F) means for raising a first longitudinal side of a portion of said press ram which is located in said high-pressure region with respect to a second longitudinal side so that said first longitudinal side is inclined with respect to said second longitudinal side by an angle .alpha.; and (G) short-stroke piston and cylinder assemblies which are located on said first and second longitudinal sides of said press and which apply said pressing force to said steel bands, the pressure in at least one of said cylinders on said first longitudinal side of said press being relieved when said one longitudinal side is raised.
18. The press as claimed in claim 17, wherein said connectors comprise spring elements.
19. The press as claimed in claim 17, wherein each of said connectors comprise bolts connecting two facing beams and spacers having mating faces which have a vertical clearance which allows said faces to slide vertically with respect to one another.
20. The press as claimed in claim 17, wherein said press has a medium-pressure region and wherein at least two of said beams are located in said medium pressure region, and further comprising connectors which connect the beams of said medium-pressure region while allowing said beams to flex with respect to one another in the direction of said pressing plane.
21. The press as claimed in claim 17, wherein each of said connectors comprises bolts connecting two facing beams, spacers connected to the respective beam, and elastic blocks provided between said spacers.
22. The press as claimed in claim 17, wherein said means for raising comprises material which is being pressed which applies a counter-pressure to said press top.
23. The press as claimed in claim 17, further comprising driving rollers and deflection rollers which guide said first and second bands around said press top and said pressing cylinder, respectively, the axis of at least one of said rollers being alterable, and an adjusting piston and cylinder assembly which alters the axis of said at least one roller through an angle .beta..
24. A device for guiding first and second steel bands about a longitudinal axis of a continuously-operating press having a high-pressure region, said bands transmitting pressing pressure to the material to be pressed and drawing said material through said press, said device comprising:
(A) a press bed;
(B) a press top composed of a plurality of beams, at least two of which are located in said high-pressure region;
(C) connectors which connect the beams of said high-pressure region while allowing said beams to flex with respect to one another in the direction of a pressing plane of said press;
(D) driving rollers and deflection rollers which guide said first and second bands around said press top and said press bed, respectively, the axis of at least one of said rollers being alterable through an angle .beta.;
(E) a plurality of co-rotating steel rods which are guided with their axes of rotation extending transversely to the direction of travel of said bands, said steel rods supporting said first and second steel bands with an adjustable press gap formed therebetween;
(F) press pillars which support said press top, each of said pillars comprising a plurality of removable drawbars and parallel upper and lower crossheads which are connected to eyes of said drawbars via one of pins and bolts; and (G) first short-stroke piston and cylinder assemblies which are located on opposed longitudinal sides of said press top and which apply pressure along a longitudinal direction of said press top creating a first variable pressure profile in said longitudinal direction.
(A) a press bed;
(B) a press top composed of a plurality of beams, at least two of which are located in said high-pressure region;
(C) connectors which connect the beams of said high-pressure region while allowing said beams to flex with respect to one another in the direction of a pressing plane of said press;
(D) driving rollers and deflection rollers which guide said first and second bands around said press top and said press bed, respectively, the axis of at least one of said rollers being alterable through an angle .beta.;
(E) a plurality of co-rotating steel rods which are guided with their axes of rotation extending transversely to the direction of travel of said bands, said steel rods supporting said first and second steel bands with an adjustable press gap formed therebetween;
(F) press pillars which support said press top, each of said pillars comprising a plurality of removable drawbars and parallel upper and lower crossheads which are connected to eyes of said drawbars via one of pins and bolts; and (G) first short-stroke piston and cylinder assemblies which are located on opposed longitudinal sides of said press top and which apply pressure along a longitudinal direction of said press top creating a first variable pressure profile in said longitudinal direction.
25. A device as recited in claim 24, including a second plurality of short-stroke cylinders which are arranged transverse to said press top and which apply a second variable pressure profile to said press top transverse to said longitudinal direction.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE9003298.5 | 1990-03-21 | ||
| DE9003298U DE9003298U1 (en) | 1990-03-21 | 1990-03-21 | |
| DEP4017791.2 | 1990-06-01 | ||
| DE4017791A DE4017791C2 (en) | 1990-03-21 | 1990-06-01 | Method and device for steel strip guidance |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2038750A1 CA2038750A1 (en) | 1991-09-22 |
| CA2038750C true CA2038750C (en) | 1999-01-19 |
Family
ID=25893784
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002038750A Expired - Fee Related CA2038750C (en) | 1990-03-21 | 1991-03-21 | Process and apparatus suitable for effecting steel band guidance |
Country Status (4)
| Country | Link |
|---|---|
| CA (1) | CA2038750C (en) |
| FI (1) | FI95674C (en) |
| IT (1) | IT1245228B (en) |
| SE (1) | SE504760C2 (en) |
-
1991
- 1991-02-26 FI FI910928A patent/FI95674C/en active
- 1991-03-06 SE SE9100658A patent/SE504760C2/en not_active IP Right Cessation
- 1991-03-15 IT ITMI910704A patent/IT1245228B/en active IP Right Grant
- 1991-03-21 CA CA002038750A patent/CA2038750C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| ITMI910704A1 (en) | 1992-09-15 |
| FI910928A (en) | 1991-09-22 |
| SE9100658D0 (en) | 1991-03-06 |
| SE504760C2 (en) | 1997-04-21 |
| SE9100658L (en) | 1991-09-22 |
| IT1245228B (en) | 1994-09-13 |
| ITMI910704A0 (en) | 1991-03-15 |
| CA2038750A1 (en) | 1991-09-22 |
| FI910928A0 (en) | 1991-02-26 |
| FI95674B (en) | 1995-11-30 |
| FI95674C (en) | 1996-03-11 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |