EP0188405B1

EP0188405B1 - An arrangement for preventing a door from dropping down precipitately

Info

Publication number: EP0188405B1
Application number: EP83903116A
Authority: EP
Inventors: Sven-Ivar Thomasson; Tomas Andersson
Original assignee: Crawford Door AB
Current assignee: Crawford Door AB
Priority date: 1983-09-26
Filing date: 1983-09-26
Publication date: 1989-01-04
Also published as: DK158238B; DK228785A; FI854991A; FI854991A0; EP0188405A1; ATE39726T1; FI78959C; DK158238C; NO161339B; DE3378836D1; FI78959B; WO1985001543A1; NO161339C; DK228785D0; NO852089L

Abstract

Arrangement for preventing a door which is movable in a substantially vertical direction and which can be acted upon by a plurality of balancing springs from dropping down precipitately. The invention makes it possible for an arrangement which functions effectively and reliably to be produced to prevent the door dropping down precipitately in the event of failure of the spring function of its balancing spring. A balancing spring is connected to a spring fixing (3, 4; 125, 126; 208) which can be acted upon forcibly to move it towards a stop position when the spring force effect of the connected balancing spring fails, and a plurality of locking elements (10, 130; 213) which are acted upon forcibly to move them into a position wherein they co-act with a locking device (13; 110) which is connected to an operating arrangement provided for the door are incorporated in the arrangement, the said locking device being designed to stop or reduce the continued movement of the door by the effect of the locking elements.

Description

The present invention relates to an arrangement for preventing a substantially vertically movable door from dropping according to the pre-characterizing portion of claim 1.
SE-B-341 681 discloses such an arrangement for preventing a substantially vertically movable door from dropping, wherein locking means are provided which, in the case of failure of the balancing spring, automatically engage with a locking device, which is rigidly linked with a door operating axle, and thus prevent any movement of the door.
Due to the rigid link between the locking means and the door operating axle in the case of engagement between locking means and locking device a rigid braking action is effected in the known arrangement. Accordingly, there is the risk of the arrangement and/or the door operation device being damaged.
Underlying the subject matter of the invention is the problem to further develop the generic arrangement so that damages of the arrangement in the case of failure of the balancing spring are reliably eliminated.
This problem is solved by features contained in the characterizing portion of claim 1. The spring element, which is disposed between the spring fixing and the door operating device and which can be designed as torsion spring and as arrangement of the springs connected in series, safeguards a gradual transmission of the braking moment so that possible peak loadings of the door operating axle are avoided. The spring element can be disposed adjacent the door operating device according to the claims 2 to 5 or in adjacent relationship to the locking means according to claims 6 to 8.
The invention is described below by way of preferred embodiments with reference to the drawing, in which:

Figure 1 shows an arrangement in a sectional view along the direction of its axis;
Figure 2 shows part of the arrangement with it held in a non-actuated stop position;
Figure 3 shows part of the arrangement with it held in an actuated stop position;
Figure 4 is an end view of the arrangement;
Figure 5 is a side view of the arrangement;
Figure 6 is a side view of an axle appertaining to the arrangement, with the associated adjoining locking wheel provided with holes;
Figure 6A is an end view of a locking wheel;
Figure 6B is a section along the line A-A in Figure 6;
Figure 7 is a side view of a fixing element;
Figure 8 is a side view of a spring fixing;
Figure 8A is a sectional view of the spring fixing with locking means received in it;
Figure 9 shows a door spring arrangement with its associated stop unit and trigger unit and the' interlinking thereof;
Figure 10 shows a further door spring arrangement with its associated stop unit and trigger unit;
Figure 11 shows the cross-linking connection for such stop units and trigger units;
Figure 12 shows a further cross-linking connection between a stop unit and a trigger unit;
Figure 13 shows a stop unit viewed transversely across its axis of rotation;
Figure 14 shows the stop unit viewed along its axis of rotation;
Figure 15 shows a trigger unit viewed transversely across its axis of rotation;
Figure 16 shows the trigger unit viewed along its axis of rotation;
Figure 17 shows another trigger unit viewed from the side;
Figure 18 shows the trigger unit shown in Figure 17 viewed from straight in front;
Figure 19 shows a brake housing appertaining to the last mentioned embodiment, viewed from the side;
Figure 20 shows the brake housing viewed from straight in front;
Figure 21 is a sectional view through parts appertaining to the brake housing;
Figure 22 shows the same parts viewed in the axial direction;
Figure 23 shows a locking ring, viewed from the side;
Figure 24 shows the locking ring viewed from the left;
Figure 25 shows a locking gear incorporated in the brake housing, partially cut away;
Figure 26 shows the locking gear from one of its sides;
Figure 27 shows a part of the opposite side of the locking gear; and
Figure 27A is a sectional view along the line B-B in Figure 27.

Described is an arrangement for preventing doors, which are movable in a substantially vertical direction in a doorway or some other aperture, which it is desired to open up or close, from dropping down precipitately if a balancing spring should breakor if its spring effect should cease due to some other cause, e.g. if a balancing spring should come away from its associated spring fixing or if the spring effect should act in the wrong direction of rotation. The arrangement functions both on hand-operated and mechanically operated doors and is not actuated until the spring failure occurs. The arrangement is also simple to mount in place, and provides a high level of safety by effectively stopping the door over a short distance when spring failure occurs. Moreover, subsequent adjustment is not required, and re-setting of the arrangement or replacement of parts after actuation is simple and requires no special tools. The arrangement is reliable and actuation is not initiated by vibrations and impacts during the movement of the door.
The arrangement is intended to be composed of three units, namely, a stop unit, a trigger unit and, in the present case, a cross-linking connection unit.
In Figure 1 a first embodiment of an arrangement 1 for preventing a door from dropping down precipitately is shown. A trigger unit 2 is formed in the arrangement 1 of a spring holder 3, preferably constructed as a plate, which bears a plurality of spring fixings 4 with which one end 5A of a balancing spring 5, preferably made as a helically wound spring, is connected, for a door which is designed to be guided in tracks along its side edges and moved along the tracks to open up or close a doorway, etc. disposed between these guide tracks. A cover 6, around which the balancing spring 5 extends, is rigidly connected, for example by welding, to the spring holder 3 and forms a so-called "neck" for the spring fixing 3, 4 which is formed as a neck fixing. An axle 7 extends
. through an opening 8 in the outer end 6A of the cover 6 while over the circumference of a holder 9 a plurality of locking means 10 are disposed, distributed along the axial extent of the arrangement 1, preferably rigidly connected to the holder 9, and preferably pin-shaped. A pressure spring 11 or a spring arrangement of some other suitable kind is designed to act between the holder 9 and the cover 6, forcibly urging the locking means 10 in the axial direction of an arrow 12, towards a locking wheel 13 provided with receiving holes 18. The locking wheel 13 is expediently mounted on one end 14A of a clamping collar 14 connected to the axle 7 and non-rotatable relative thereto. The axle 7 extends through the arrangement 1, which can be doubled up due to the fact that the clamping collar 14 may be fitted with a further locking wheel 13' on the opposite end 14B of the clamping collar 14 with which appropriate locking elements of another arrangement for preventing precipitate dropping down can coact in a similar way as in the arrangement 1 described above. The clamping collar 14, which is preferably slit along one of its sides, is connected via a bracket connection 15 to a plurality of wall mounting brackets 16 for example, and is securely clamped to the axle 7 by means of a plurality of bolt units 17 around a wedge 7B which acts between the axle 7 and the clamping collar 14.
Over the circumference of the locking wheels 13 and 13' respectively there are disposed the receiving holes 18 adapted to the locking means 10.
A fixed plate or a similarly constructed fixed element 19 is connected to the wall mounting bracket 16 by means of screws 20, for example, so that it cannot be rotated. The fixed element 19 has a sleeve-shaped bearing 21 which is designed to accommodate, for example, a circular ball bearing 22 to act between the axle 7 and the arrangement 1 containing the fixed element 19.
A plurality of spacer sleeves 23 are accommodated in corresponding slit-shaped grooves 24 extending over the circumference of the fixed element 19 and in holes 25 adapted to the spacer sleeves 23 and extending through the spring holder 3, and are held together by means of a screw 26 and a nut 27 in such a way as to allow the fixed element 19 and the spring holder 3 to be rotated relative to each other.
A trigger spring 28, such as a helical tension spring, for example, is fixed by one 28A of its ends to a part 19A of the fixed element 19 and is connected by its other end 28B to a spring fixing lug 29 projecting out from the spring holder 3.
The operation of the above-described arrangement 1 is as follows: During normal operation of the door the tension moment is transferred from the balancing spring 5, which is connected non-rotatably via its other free end to the axle 7, which forms the connection to a door operating device, such as a cable pulley, for example. Normally the balancing spring 5, or balancing springs in the case where more than one is provided, balances the door so that it can be moved easily in the desired direction. When, for example, spring breakge or some other spring failure occurs, the tension moment from the balancing spring 5 ceases to act on the spring holder 3. Due to the effect of the trigger spring 28 the spring holder 3 is rotated in the direction of an arrow 30 which is made possible due to the fact that the greater ·moment which is obtained from the balancing spring 5 has ceased to exist. A number of through- bores or holes 31 adapted to the locking means 10 thereby come into position directly in front of respective locking means 10, which were previously urged by the pressure spring 11 to rest against the fixed element 19 on a sliding surface 19b, which is bounded in the lateral direction of the holes 31, which can also be surrounded by the sliding surfaces 19B. The locking means 10 quickly come into engagement with their associated corresponding receiving holes 18 of the locking wheel 13 or 13' respectively after they are inserted via their front section through the holes 31 and the spring holder 3 rotates around the axle 7 as the spacer sleeves 23 move along the slit-shaped grooves 24 in the fixed element 19. The locking wheel 13 is hereby prevented from rotating with the axle 7 and the movement of the door ceases or is reduced in this way. The axle 7 acts here with a damping effect since it acts like a torsion spring which prevents the operating mechanism, such as ropes and axles, for example, from being overloaded by violent jerking due to the direct and effective locking of the movement. It is consequently desirable that the arrangement 1 is mounted with a certain minimum spacing from the cable drum, etc.
After the arrangement 1 has been actuated it is possible to re-set it to the ready-for-locking state, after replacement of balancing springs, etc. which may be required.
By means of a split pin 32, for example, which acts between the fixed element 19 and the spring holder 3 it is possible to prevent the movement of these parts, for example when the arrangement 1 is being assembled.
An arrangement 101 for preventing a door from dropping down precipitately, which is shown on the drawings in Figures 13-27, may comprise three units: namely, a stop unit 102, a trigger unit 103, and a cross-linking connection unit 104, the arrangement containing at least the first two units mentioned.
Figure 9 shows how, depending on door weight and hoisting speed, for example in an arrangement according to Figures 13-27, two trigger units 103 are both joined to their respective balancing spring 106 connected to a hoisting operation axle 105, with a stop unit 102 connected to one of the trigger units 103 and linked to the other trigger unit 103 via a cross-linking connection unit 104.
Figure 10 shows how trigger units 103 joined to their respective balancing spring 106 are connected to their respective stop unit 102 located by the respective trigger units 103, and are connected in a cross-over fashion to each other via the cross-linking connection units 104.
Figure 11 shows the coupling together of two separately mounted trigger units 103 with an integrated trigger and stop unit 107 via a cross-linking connection unit 104 made up of springloaded lines 108.
Figure 12 shows how the cross-linking connection unit 104 can be composed of a plurality of separate interconnected lines 109.
An integrated trigger and stop unit 107, or a separate stop unit 102, which is shown in Figures 13-14, comprises two elements which are counter-rotatable relative to each other, namely, a locking ring 110 and a locking gear 111, which are designed to rotate with each other when the door is operating normally. The locking elements 110, 111 have a plurality of friction surfaces 112 and 113 respectively, disposed over the opposing side surfaces 110A and 111A respectively and sloping in a tangential direction; these friction surfaces 112, 113 are continued into locking surfaces 114 and 115 respectively which extend in the axial direction. Over the circumference of the locking ring 110 a plurality of tooth elements 116 are arranged, preferably evenly distributed; with these tooth elements 116 a plurality of locking dogs 130, which are bearing-mounted so that they can rotate around bearings 118 disposed on the circumference of the stop unit 102, are able to co- act.
The locking gear 111 is connected non-rotatably to the locking ring 110 during normal operation, for example by means of tooth elements 110B and 111B respectively. The two locking elements 110, 111 are acted upon by a spring element 120, preferably a stack of disc springs compressed between locking elements 121 and 122 respectively, such as locking rings, for example, which co-act with the axle 105, 119 and are provided on either side of the locking elements 110,111 and the spring element 120, urging them towards each other so that the locking surfaces 114, 115 are engaged with each other during normal operation of the door. Flange arrangements 123 and 124 arranged between the two locking elements 110, 111 respectively are designed to form a rotating bearing between the locking elements 110, 111.
In order to avoid peak loading on the axle 105 when the braking phase is begun, and to reduce the effect on the braking moment of the coefficient of friction at the sloping friction surfaces 112, 113, the friction surfaces 112, 113 on the two locking elements 110, 111 are, as stated above, made with a sloping plane. This makes it possible for the braking moment to be engaged "gently" and to be increased with the rotary angle until the maximum value is reached and/or the movement of the door is stopped. To obtain the greatest ppssible quantity of work it is expedient to select the springs of the spring element 120 with a degressive spring characteristic. The desired braking moment forthe arrangement 101 can easily be obtained, as stated, by varying and adjusting the spring force and/or varying the angle of inclination A at the friction surfaces 112, 113.
In the integrated trigger and stop unit 107 which is shown in Figures 19-20 one end of the balancing spring 106 can be connected to a spring holder 125 and its other end to the drive axle 105.
A trigger unit 103 which is shown in Figures 15-16 and 17-18 and which comprises a spring holder 126 to which a second balancing spring, quite separate from the balancing spring which is connected to the spring holder 125, is connected to the spring holder 125 via a cross-linking connection unit made, for example, as a cord 127, by passing itthrough an opening 128 in the periphery thereof. The cord 127 also extends via a releasing ring 129 which is designed to act on the locking dogs 130, which are urged by a spring element 117 to pivot in the direction of the locking ring 110 and the toothed elements 116 appertaining thereto.
The cord 127 extends further over a pulley or the like (not shown) to a further trigger unit 103. If the cord·127should go slack,which occurs if any ofthe inter-connected balancing springs breaks or its spring effect is reduced in some other way, the spring holder or fixing 125 which is guided over the circumference of the unit 107 in slit-shaped openings 131 via controlling bolts 132, is able to rotate in the direction of an arrow 133, and thereby rotates the releasing ring 129 with it. When the cord 127 goes slack the locking dogs 130, which are normally influenced by the releasing ring 129 by co-action between a projection 135 provided on the respective locking dogs 130 and a stop 134A located at one end of a slit-shaped recess 134 in the releasing ring 129, for example, forcing them out of engagement with the tooth elements 116 on the locking ring 110 against the effect of the respective spring elements 117 on the respective locking dogs 130, are able now to be pivoted round the locking dog bearing 118 under the effect of the associated spring elements 117, and in towards the tooth elements 116 on the locking ring 110, blocking its rotary movement.
With the locking ring 110 locked against continued rotary movement, under the effect of the . door operating device the locking gear 111 strives to continue to rotate. Due to the slope on the opposing side surfaces 110A and 111A respectively, the spring element 120 is compressed and the braking moment is increased rapidly, whereby the movement and the operation of the door is stopped.
The trigger unit 103 consists of the above-mentioned spring holder or fixing 126 and a fixed bracket 136 around which the spring fixing 126 is rotatably mounted via pins 137 which are accommodated in slit-shaped openings 138 disposed in the spring fixing 126, i.e. there are similar parts to those which form the stop unit located in the central part of the integrated stop and trigger unit 107. A trigger spring 140 acts between the spring fixing 126 and the fixed bracket 136, urging the spring fixing 126 to rotate relative to the fixed bracket 136.
Re-setting of the arrangement again in the ready-for-braking state is effected simply by coupling up the existing cross-linking connection cords 127 in the above-mentioned way, after replacing any faulty balancing springs etc.

Claims

1. An arrangement for preventing a substantially vertically movable door from dropping, said door being acted upon by a balancing spring (5; 106), which is connected to a spring fixing (3, 4; 125, 126), said spring fixing (3, 4; 125, 126) moving towards a stop position, if the spring force of said balancing spring (5; 106) fails, and locking means (10; 110, 116), which are disposed on said spring fixing (3, 4; 125, 126), engageable with a locking device (13, 130), thus stopping the movement of a door operating device comprising an axle (7; 105), characterized in that said locking means (10; 110, 116) is axially movable with respect to said axle (7; 105) of said door operating device and that between said spring fixing (3, 4; 125, 126) and said axle (7; 105) of said door operating device is provided a spring element (11; 120) for damping the transmission of the braking moment between said spring fixing (3, 4; 125, 126) and said axle (7; 105) of said door operating device.

2. An arrangement according to claim 1, wherein said balancing spring (5) is helically wound and connected at one (5A) of its ends to said spring fixing (3, 4), which comprises a spring holder (3) rotatable relative to said locking device (13) and to a fixed element, preferably constructed as a fixed plate (19), respectively, and that a trigger arrangement, preferably constructed as a trigger spring (28), acting between said spring holder (3) and said fixed element (19), is adapted to rotate said spring holder (3) relative to said fixed element (19).

3. An arrangement according to claim 2, wherein said fixed element (19) has a plurality of holes (31) through which said locking means (10) pass, if they come into a position directly in front of the corresponding holes (31) after relative rotation between said fixed element (19) and said spring holder (3).

4. An arrangement according to claim 3, wherein said locking means (10) are pins which can be received in said locking device (13) comprising at least one locking wheel (13) equipped with receiving holes (18) and connected to said axle (7), said axle (7) being mounted in a bearing (21) connected to said door operating device and preferably designed as a torsion spring element.

5. An arrangement according to claim 4, wherein said pins (10) are mounted on a holder (9) which can be acted upon forcibly by a pressure spring (11) to be moved towards said receiving holes (18) of said locking wheel (13).

6. An arrangement according to claim 1 or 2, wherein said locking means comprises a locking ring (110), which is acted upon forcibly by said spring element (120) to be moved towards a locking gear (111) and which locking ring (110) is mounted non-rotatably relative to said axle (119) of said door operating device, said locking ring (110) and said locking gear (111) being designed to rotate normally counted to each other.

7. An arrangement according to claim 6, wherein said locking ring (110) has tooth elements (116) distributed over its circumference, with which said locking device (130), preferably constructed as a locking dog (130), which can be acted upon by a releasing ring (129) which can co- act with said spring fixing (125, 126), is engageable, and wherein said locking ring (110) and said locking gear (111) having friction surfaces (112, 113) sloping in a tangential direction, which may co-act with each other and which are continued into axially extending locking surfaces (114,115).

8. An arrangement according to claim 6 or 7, wherein said spring element (120) comprises a plurality of springs having degressive spring characteristics, preferably disc springs.