ROLL-UP DOOR

Abstract: Roll-up door comprising two door-leaves (4) arranged to be wound onto and off a common roll-up roller (14). The door-leaves (4) are kept spaced apart by a roller (16) and a rigid profile member (6) at the lower ends of the doorleaves where the latter are interconnected. The rigid member (6) is guided by carriages (8) which are rotatably mounted at the member ends and travel in U-beams (10). Belts (22) are secured to the carriages (8) and are carried about a number of pulleys (24, 26, 28, 30, 34) and are wound onto and off discs (36) which are mounted on the same shaft (38) as the roller (14) onto which the door-leaves (4) are wound on and off, whereby the door-leaves (4) will be maintained tensioned and their weight balanced.

Description: Roll-Up Door The subject invention concerns a roll-up door the door-leaf of which is flexible and arranged to be wound onto a roll-up roller. Several different types of doors are available on the market, such as: a) Continuous, rigid door panels; b) Sectionized, rigid door-panels, the sections of which are hingedly interconntected; c) Door-panels consisting of steel lamella; d) Doors made from aluminium profiles arranged to be telescopically nested in one another. A feature common to all types of doors mentioned above is that in their open position they are collected above the door opening and for this reason several of them require considerable headroom space vertically or in the plane above the opening. For all the door types mentioned above the speed of opening up and closing the doors is very low, resulting in considerable hold-up time for internal -transport vehicles, particularly when double doors including an air lock are used in which case one door has to be shut before the second one is opened. Another type of prior-art door consists of a roll-up door comprising a single door-leaf which is arranged to be wound onto a roll-up roller. The door opening and closing movements are rapid, the door operation is noiseles and the space required to accommodate the door-leaf in its open position is minimal. This prior -art door is particularly suitable for use between two premises or rooms to avoid disturbing air currents and noise between the two premises. Because it may be closed and opened rapidly the door is also suitable for use between premises and the outside where a heavy traffic load makes it necessary to open and close the door frequently, such as for instance is the case at goods -reception stations.However, because the door-leaf is comparatively thin and not insulated, this type of door has the disadvantage that a considerable amount of energy is consumed to maintain the area immediately inside the door at the desired temperature level. In addition, when the door is used to interconnect a noisy room and a comparatively quiet room it has proved to be difficult to satisfactorily prevent the noise from penetrating into the quiet premises. This situation could, of course, be remedied by arranging two roll-up doors in succession but this solution is a comparatively expensive one, since two complete door arrangements are required. The prior-art door construction comprises a device designed to maintain the door-leaf in stretched condition vertically and at the same time balanced with the aid of tensioning devices, located in their respective one of the two side frames. The tensioning device may consists for instance of a moveable weight-actuated wire or belt pulley through which is carried a wire or belt. One end of the wire or belt is attached to the lower end of the door leaf.= The opposite wire or belt end is arranged to be wound on and off a wire or belt pulley which is connected to the wind-up roller of the door-leaf, in the opposite direction from the winding-on and winding-off of the door leaf itself. The load which may be a weight, a spring or some other suitable device is divided into two opposing counter -balancing load components. Half the load acts on the wire or belt pulley provided ow#the roll-up roller. This ##- component is transferred to the door-leaf as a consequence of the winding-on and winding-off of the wire or belt in the opposite direction to the door-leaf movement in the form of an upwardly directed force. The other half of the load acts as a downwardly directed force acting on the lower edge of the door-leaf. Balancing of the dead weight of the door-leaf must be effected by providing for difference in the moments or radii of the roll-up roller ot the door-leaf and of the wire or belt pulley associated therewith. When the radius of the pulley is the larger one the vertically upwards directed force acting on the door-leaf will be reinforced and exceed the downwards directed force. The difference in forces will counteract the dead weight of the door -leaf and balance it. However, it has proved to be difficult, at least when the doors are very wide and their dead weight therefore considerable, to obtain sufficient difference in forces. The difference of moments (difference of radii) that this would require is of such a magnitude that the dimensions of the wire or belt pulley inevitably would become unproportionally large. The difference of moments (radii) also affects the movements of the weight in the side frame and therefore the space allowed for the movements of the weight may be insufficient. When the load is in the form of a spring the spring movements become unproportionally large and affect the serviceable life of the spring. The roll-up door in accordance with the subject invention has for its purpose to remedy the drawbacks outlined in the aforegoing while at the same time provide good insulating effects. At the same time, the door according to the invention possesses all the advantages of single door-leaf roll-up doors. These objectives are obtained in the roll-up door in accordance with the subject invention by providing the door in accordance with one embodiment thereof with double door-leaves arranged to be wound onto and to be wound off a common roll-up roller. Preferably, the lower ends of the double door-leaves are attached to, alternatively carried around, a rigid profile member which is supported by the interconnected door-leaves. A tensioning device in the form of a belt or the like may be arranged in the frame members at either side of the roll-up door and secured to the latter, said belt arranged to be wound onto or off a drum in a direction opposite the winding-on and winding-off direction of the door leaf. The belt or similar means is preferably arranged to be wound onto a belt pulley which is mounted on the same shaft as the roller onto which are wound the door-leaves The belt and the door-leaves are wound onto respectively the pulley and the roller in opposite directions. An elongate, flexible sealing cloth is preferably suspended from the lower end of the roll-up door and secured to the double door-leaves of the door. A photoelectric cell arranged to emit a beam of light between the sealing cloth and the rigid member may be so connected to the motor operating the door-leave movements that as soon as the beam of light emitted by the photoelectric cell is interrupted the winding-off of the door ceases In order to stiffen the door-leaves one or several members may be arranged to be lowered together with the door into abutment against stop means which are conceived to stop and support the stiffening members at suitable spaced -apart positions. In accordance with one embodiment of the invention a second tensioning device is arranged in each one of the side frames to act on the roll-up roller to provide a force counteracting the force of gravity of the door-leaf. The invention will be described in closer detail in the following with reference to the accompanying drawings, wherein Fig. 1 is a cross-sectional view through the door along line 1-1 of Fig. 2, Fig. 2 is a cross-sectional view along line Il-Il of Fig. 1 through the end wall of the construction in accordance with the invention, Fig 3 is a tensioning device associated with the door, Fig. 4 is a cross-sectional view of the roll-up door as seen from the side, Fig. 5 illustrates the tensioning and balancing device in accordance with the invention to be used in a single-leaf roll-up door in accordance with the invention, Fig. 6 is a somewhat modified embodiment of the device of Fig. 5 and Fig. 7 is a corresponding device in accordance with one embodiment thereof modified for use in a double-leaf roll-up door. The roll-up door in accordance with the embodiment shown in Figs. 1-4 is designated generally by numeral 2. This door consists of two door-leaves 4 forming a double -cloth door-leaf. The cloths are interconnected at their bottom ends around a rigid profile member, such as a tube 6. The tube serves both as a weight-balancing means to achieve equal tensioning of the two door-leaves and as a guide means to control the movements of the door 2. The ends of the tube 6, only one of which is shown in the drawings (Figs. 1 and 2), are rotatably mounted in a carriage 8 which is arranged to run in a U-shaped beam 10 the open side of which faces the door-leaves 4 and which beam forms a guide means to control the movements of the carriage 8. The U-beam 10 is mounted in a profile member 12 forming the frame and end post of the roll-up door 2. A corresponding frame member (not shown) is provided at the opposite side of the door 2. The door-leaves 4 are pulled up and down by being wound onto and off a roller 14, whereby the two door-leaves 4 are wound onto and off said roller. The door leaves 4 are kept in spaced relationship both by the tube 6 and by a roll 16 about which is carried one of the door leaves 4. In this manner the two door-leaves 4 forming the roll-up door 2 will be suspended in parallel relationship along principally the entire extension of the door when the latter is in its fully pulled-down position, that is closed. The relative movements occurring between the two door-leaves 4 as a result of each winding turn of one of the leaves being wound on top of the other leaf on the roller 14 are compensated for in a simple manner by turning the profile member 6 or by biasing the roll 16 by a spring. At the lower end of the roll-up door 2 is provided a flexible, elongate sealing cloth 18. By means of attachment members 19 the two ends of the cloth 8 are secured to their respective one of the door-leaves 4. The cloth 18 hangs freely like a loop or pocket below the tube 6. In the lower (closed) position of the door the cloth will abut against the substructure/ground, thus forming an insulating means protecting against floor draughts. In this manner good insulation effects are obtained also when the ground/floor is uneven, sloping, etcetera. A system including a photoelectric cell 20 arranged on the carriage 8 cooperates with a beam of light emitted between the two carriages in parallel with the tube 6 and in the lengthwise direction of the sealing cloth 18 inside the loop formed by the latter. In case the sealing cloth 18 bends upwards as a result of an obstruction, for instance by the presence of a person or a vehicle underneath the door, blocking the path of movement of the cloth 18 during the closing movement of the door 2, the beam of light is interrupted and the closing movement of the door is stopped. It may even be preferable to arrange for the door to re-open automatically over a short distance when the closing movement has been stopped. Owing to the interruption of the door closing movement before the tube 6 reaches the obstacle or blocking object accidents may be avoided. Alternatively, the safety function may be provided in other conventional ways, for instance by the provision of a pneumatically operated rail, a tape-switch, to mention only a few. The door in accordance with the invention is provided with a special tensioning device comprising a belt 22 which is attached to the carriage 8. The belt 22 extends in a downwards direction from the carriage and immediately above ground level it is passed about two pulleys 24, 26 from whence it runs upwards towards a third pulley 28 which is positioned at the upper portion of the roll-up door 2 (see Fig. 3 and the left part of Fig. 1). On its run from the carriage 8 to the pulley 28 the belt 22 is turned over a quarter of a turn about is lengthwise axis, whereby at the level of the pulley 28 and beyond, the belt 22 will extend in parallel with the door-leaves 4. From the pulley 28 the belt 22 runs downwards and about a fourth pulley 30 which is secured to a spring 32 and further up and around a fifth pulley 34 and finally to a wind-on disc 36. The disc 36 is mounted on the same shaft 38 as are the roller 14, the corresponding wind-on disc for the belt 22 at the opposite side of the door 2 (not shown) and a motor 40 producing the motions of the roller 14 and the discs 36. Owing to the mounting of these means on a common shaft the door-leaves 4 will be paid out when the belts 22 are paid in because the latter are wound on the discs 36 in a direction opposite to that of the door-leaves 4. By selecting the diameters of the discs 36 to ensure that the diameters of the belts 22 wound onto the discs 36 in all positions of the door exceed the diameter of the door -leaves 4 wound onto the roller 14 an increased tensioning force exerted on the door-leaves is obtained upon door closing movements because the spring 32 is tensioned gradually as a result of the length of the belt 22 wound onto the disc 36 exceeds the length of the door-leaf 4 which is wound off from the roller 14. The width of the door-leaves 4 exceeds the length of the tube 6 and their side edges project into the U-profile member 10, see Fig. 2 (and Fig. 1). This increases the sealing effect at the side frames of the door 2 when the latter is in its lower position. The side edges of the door -leaves 4 are slitted at their lower ends in such a manner that each door leaf 4 forms a depending flap 42 below and laterally of the tube 6. One or several stiffening members in the form of tubes or beams 44 between the two door-leaves 4 are arranged to be lifted and lowered by the carriages 8 to and from a position at suitable spacings when the door 2 is in its lower position. Fig. 1 shows a stiffening member 44 supported on a pair of abutments 46 which preferably are secured to the U-profile members 10. This tube 44 gives stability to the door 2 in the lowermost position of the latter and prevents it from serving as a wind-catcher means of sail or balloon type. Fig. 6 shows the manner in which the tensioning device is supplemented with a weight 48 which by means of a block 50 is suspended in a wire 52. The weight is suspended ed SO as to tend to turn the disc 36 in the same direction as the tensioning belt 22 and consequently it reinforces the moment of force by means of which the tensioning belt 22 acts on the disc 36. In this manner the weight 48 serves to balance the weight of the door-leaves 4 upon operation of the door, and to tension it. The weight 48 is particularly suitable for use in larger doors in order to avoid big and bulky tensioning devices comprising the tensioning belt 22 and the spring 32. Figs. 5 and 7 show modifications of the invention. The door-leaf 61, which is a single- or do.ble-leaf door, is wound on and off a rov up roller 62 corresponding to roller 14. A belt 64 or similar means is attached to the lower end 63 of the door-leaf. The belt 64 is carried around fixed discs 65 and around a movable disc 66 which is weighted by a tensioning device, the opposite end of said belt being wound onto a disc 67 which is mounted on the same shaft as the roll-up roller 62. The movable disc 66 is weighted by a tensioning device, preferably a spring 68. The spring force is divided into two components one of which is transf erred via the discs 65 to the door-leaf 61 as a vertically downwards directed force. The other force component is transferred to the disc 67 and the roll-up roller 62 and acts on the door-leaf 61 as a vertically upwards directed force. To the downwardly directed force should be added the force of gravity of the door-leaf, The latter force may be wholly or partly compensated for by the difference of moments (difference of radii) between the disc 67 and the roll-up roller 62. Wide and heavy doors may need further balancing. This is achieved by the provision of a weight 69 which acts on the door-leaf 61 as an upwardly directed force via the belt 70, the disc 67 and the roll-up roller 62. All of the weight 69 may act on the door-leaf as is the case in the embodiment illustrated in Fig. 5 but in this case its movements will be rather large. In order to reduce its movements the weight 69 may be suspended from a moveable disc 71 (Figs. 6 and 7). One end of the belt 70 is attached to the fixed frame of the roll-up door. Only half of the load of the weight 69 acts on the door-leaf but on the other hand its movements are smaller. A number of advantages are obtained with a roll-up door in accordance with the invention. With the double-leaf version of the door excellent insulation is obtained as a result of the insulating air layer formed between the two leaves. This makes it possible to use the door between heated and non-heated premises or between the inside and the outside of a building. The balancing with the aid of the belts 22 and, when applicable, the weight 48, also makes it possible to raise and lower the door 2 quickly and to operate it by means of a small motor 40. The embodiments of the invention described in the aforegoing are to be regarded as examples only and other embodiments are possible within the scope of the appended claims. For instance the springs and weights, such as spring 68 and weight 69 may be replaced by other tensioning devices.

Claims: Claims 1. A roll-up door having a flexible door-leaf arranged to be wound onto a roll-up roller, said door-leaf attached, preferably at its lower end, to tensioning devices arranged in their respective side frame on either side of the door-leaf, said tensioning devices also arranged to act on the roll-up roller essentially to provide a tensioning effect in the door-leaf between said roller and the lower end of the door-leaf, c h a r a c t e r i s e d i n t h a t said door comprises double door-leaves which are arranged to be respectively wound onto and wound off the common roll-up roller. 2. A roll-up door as claimed in claim 1,c h a r a ct e r i s e d i n t h a t the double door-leaves are interconnected at their ends at or about a rigid profile member supported by the interconencted door-leaves. 3. A roll-up door as claimed in claim 1 or 2, c h a r a c t e r i s e d i n t h a t at its lower end said roll-up door is provided with a depending flexible and elongate sealing cloth, which cloth is attached to the double leaves of the door. 4. A roll-up door as claimed in any one of claims 1, 2 or 3, c h a r a c t e r i s e d i n t h a t a photoelectric cell is arranged to emit a beam of light between the sealing cloth and the rigid profile member, and in that the motor producing the door movements is arranged to interrupt the winding-off of said door upon interception of the beam of light emitted by said photoelectric cell. 5. A roll-up door as claimed in claim 1, c h a r a ct e r i s e d i n t h a t one or several stiffening members are arranged to be lowered together with the door and that stop means are arranged to stop and support said stiffening members at suitable spacings. 6. A roll-up door comprising one or several flexible door-leaves arranged to be wound onto a roll-up roller, said door-leaf attached, preferably at its lower end, to tensioning devices provided in their respective side frame on either side of the door-leaf, said tensioning devices likewise arranged to act on the roll-up roller essentially to provide a tensioning effect in the door leaf between said roller and the lower end of the door leaf, c h a r a ct e r i s e d i n t h a t a second tensioning device is arranged in each side frame to act on the roll-up roller to provide a force counteracting the force of gravity of the door leaf. 7. A roll-up roller as claimed in claim 6, c h ar a c t e r i s e d i n t h a t each tensioning device is a belt or similar means arranged to be wound onto and off a disc which is mounted on the same shaft as the roller onto which the door leaf is wound, and in that said winding -on and winding-off of the belt is effected in a direction counter to the direction of winding-on and winding-off of the door leaf. 8. A roll-up roller as claimed in claim 7,c h a r a ct e r i s e d i n t h a t the belts or the equivalent means which are arranged in the smae side frame are wind onto or off a common disc.

Inventors: MANNS, BERNT HUGO
Applicants: NOMAFA AB
Application year: 1984
Main classification: E06B9
IPC codes: E06B9