DE102020114154B4 - Crank mechanism for electrically driven blinds - Google Patents

Abstract

Crank gear (2) for an electrically driven curtain, comprising a bevel gear (10) with a gear base (4) in which a hollow shaft (8) connected to a pinion is guided, in the opening of which a hand crank (not shown), in particular in a non-positive connection, can be inserted, and with a gear body (12) which has a gear rim which is arranged at the lower end of the gear base (4) and into which the pinion engages, the crank gear (2) being mounted on the end of the gear body (12 ) has a winding shaft bearing (14) for a winding shaft for winding and unwinding the curtain, and wherein the bevel gear (10) has a reduction ratio in the range from 2:1 to 4:1, in particular 3:1.

Description

The invention relates to a crank gear for an electrically driven blind, comprising a bevel gear with a gear base, in which a hollow shaft connected to a pinion is guided, into whose opening a hand crank can be inserted, and with a gear body, which has a gear body arranged at the lower end of the gear base Sprocket has, in which the pinion engages. It also relates to an electrical operating device for a curtain.

Electrically driven hangings are, for example, roller shutters, awnings or blinds, which are retracted in an upper end position and do not cover an area such as a window in this position, while in a lower end position they serve to cover or shade the area. A switch can be actuated to raise or lower the curtain, which activates an electric motor.

A mechanical drive is used to rewind the curtain in an emergency or power failure to clear an escape route or opening or area.

Emergency hand crank motors are known from the prior art, which have an unfavorable reduction ratio in order to quickly move a blind upwards. Reduction ratios of 23:1 to 38:1 revolutions are typically necessary for the winding shaft to make one revolution. This means that the winding shaft has to make seven revolutions to release a door-high element on a maxi tank. Accordingly, 161 to 266 turns must be made by hand on the crank rod in order to move the curtain to the upper end position.

Also known are systems with springs. Springs in or at the end of the winding shaft ensure that the curtain is automatically wound up on the winding shaft after a safety device has been triggered by the spring force. These systems are awkward to assemble and hit the upper stop of the curtain at very high speed, which in turn can lead to damage to the facade. This can be avoided by reducing the spring tension, which in turn means that the curtain is not completely moved to the upper end position and the necessary opening height, such as with parapet windows, is not guaranteed. The same applies if the spring force decreases.

the DE 10 2016 125 688 A1 describes a shading device with an emergency opening function, which includes an electric drive motor and a winding shaft for a curtain, with an emergency drive being connected to the winding shaft via a clutch. The shading device has a freewheel that is connected to the winding shaft. The winding shaft is rotatably mounted on a bearing cap via a ball bearing.

From the DE 69 15 935 U a crank mechanism for an electrically driven curtain with a freewheel is known. The crank gear comprises a bevel gear with a gear base, in which a hollow shaft connected to a pinion is guided, in the opening of which a hand crank can be inserted, in particular in a non-positive connection, and a gear body, which has a toothed rim arranged at the lower end of the gear base which engages the pinion, the crank mechanism having a winding shaft bearing for a winding shaft for winding and unwinding the curtain at the end of the gear body facing away from the gear base.

the CH 360 305 A discloses an electrically operated winding system for a curtain having a winding shaft and a reduction gear with a plurality of gears

the DE 71 47 737 U describes an electrically operated roller blind with an electric drive. It comprises an auxiliary shaft directed parallel to a drum, which can be non-positively connected to the main shaft of the arrangement by axial displacement in the direction of rotation, counter to the action of resilient means. At the free end of the auxiliary shaft there is provided a manual actuating device, one of the ends of the auxiliary shaft arranged in the axis of the main shaft being provided with a lug for engagement with the opposite end of the main shaft, while the end opposite thereto slidably carries a small bevel gear permanently connected to a in a suitable form in the housing mounted gear meshes.

The invention is therefore based on the object of specifying a crank mechanism for electrically driven blinds in which the disadvantages of the prior art are avoided. In particular, rapid raising of the curtain should be made possible in an emergency. Furthermore, an advantageous actuating device for a curtain is to be specified.

With regard to the crank mechanism, this object is achieved according to the invention with a crank mechanism with the features of claim 1.

According to the invention, the bevel gear has a reduction ratio in the range from 2:1 to 4:1, in particular 3:1.

Advantageous configurations of the invention are the subject matter of the dependent claims.

The invention is based on the consideration that, in an emergency, the possibility of quickly raising a curtain is of immense importance. Releasing an escape zone too late can result in panic, injury or even death. In known emergency devices too many revolutions of a crankshaft are required or a reliable transport of the curtain in the upper end position is not possible.

As has now been recognized, the above requirements can be met by using a bevel gear which has a very low reduction ratio.

The winding shaft bearing is advantageously designed for 40, 50 and 60 winding shafts.

According to the invention, a freewheel is provided between the winding shaft bearing and the gear body. During a rotation of the gear body (the winding shaft), which is (which) is driven in particular by an electric motor, when the curtain is transported to a desired position with the aid of the motor during normal operation, the crank should not rotate. The freewheel is preferably designed in such a way that a frictional connection between the hollow shaft or crank and the gear body or winding shaft only takes place after a predetermined number of revolutions (including not complete revolutions) or a predetermined number of degrees of rotation of the gear body or the winding shaft. The freewheel is particularly preferably designed in such a way that the crank does not turn when the blind is being transported from an upper end position to a lower end position.

According to the invention, the freewheel comprises at least one freewheel ring coupled to the gear body with a lug extending circumferentially in the axial direction of the gear body, the winding shaft bearing comprising a driving area for one of the lugs of the freewheel ring, which limits the relative radial movement between the freewheel ring and the winding shaft bearing. The freewheel ring can be firmly connected to the gear body, or a recess for the nose can be provided on the gear body. Transmission bodies and/or winding shaft bearings can form a form-fitting connection, in particular with play, with a nose of the corresponding freewheel ring. For this purpose, the recess can have two stops, so that when the freewheel ring rotates relative to this recess, the lug strikes a stop of the recess, thereby preventing further mutual rotation.

According to the invention, a plurality of freewheel rings arranged one behind the other in the axial direction of the transmission body is provided, with two lugs of adjacently arranged freewheel rings blocking one another in the direction of rotation in the assembled state. This means that after two adjacent freewheel rings rotate against each other, the lugs collide and prevent further rotation in the same direction of rotation. The lugs or axial projections block each other preferably only between immediately adjacent freewheel rings. In this way, the total angle of rotation can be maximized until all freewheel rings lock in the direction of rotation in pairs and rotate synchronously.

The number of freewheel rings and/or the width of the lugs is advantageously selected in such a way that after a predetermined number of revolutions of the gear body, a non-positive connection of the hollow shaft and the winding shaft bearing occurs. This number of revolutions preferably corresponds exactly to the number that is required to transport the curtain from the upper end position to the lower end position.

Advantageously, the crank mechanism includes a crank lock, which allows the crank to turn in only one direction of rotation. This prevents the crank from turning in the wrong direction, so that in an emergency no time is wasted because it is not recognized that the direction of rotation used does not result in the curtain being transported to the upper end position.

The crank lock is preferably designed in such a way that it can be removed and/or folded away in a lower (upper) end position of the curtain. In this way, the frictional connection can be reset in the lower (upper) end position.

The invention does not relate to a crank gear with a bevel gear with a gear ratio of 5:1 to 8:1

The invention also does not relate to a crank gear in which a worm gear with a transmission ratio between 2:1 and 4:1 is used instead of the bevel gear.

With regard to the actuating device, the above-mentioned object is achieved according to the invention with an actuating device having the features of claim 5.

Advantageously, the actuating device has a drive motor, which is coupled to the gear body (via the hollow shaft) by a freewheel driver for the direction in which the curtain is moved upwards (“up direction”). With the help of the motor, the curtain can be conveniently transported to the desired position in normal operation.

The drive motor preferably has a brake, by means of which the winding shaft bearing is rotationally fixed. In this way, the curtain can be fixed in any desired position between the two end positions.

In an assembled state, the motor (is) is advantageously fastened on one side and the bevel gear on the opposite side on a box inside of a box for a curtain.

Both drives, i.e. the motor and the bevel gear, are connected to the winding shaft. The motor can move the curtain in both directions while the crankshaft (crank rod) does not turn. The bevel gear can only move the curtain up and not down. The motor or its brake holds the curtain in any position between the two end positions of the curtain. If the curtain was operated via the bevel gear and thus moved to the upper end position, the motor can move the curtain back to the lower end position. The crankshaft (rod) only rotates during this so-called "reset run".

The actuating device preferably comprises a rotationally bound safety device which, in a normal operating mode, allows the hollow shaft to rotate in one direction of rotation and blocks it in the opposite direction of rotation. The safety device is preferably designed in such a way that it can be deactivated in a further operating mode, in particular to reset the frictional connection, in such a way that rotations in both directions of rotation are possible.

The invention also relates, in particular as part of the actuating device described above, to a rotationally bound safety device for a pivot bearing, in particular a pivot bearing, with a rotatable hollow shaft. The fuse comprises a blocking element attached to the hollow shaft and a movably, in particular rotatably, mounted blocking element. The blocking element protrudes from the hollow shaft, in particular perpendicularly. The blocking element is arranged in such a way that in one direction of rotation the blocking element is blocked by the blocking element in such a way that further rotation is not possible, and that in the opposite direction of rotation there is no blocking or blocking, in particular because the blocking element deflects the blocking element, whereby a further rotation is allowed.

In a preferred embodiment, the blocking element is designed as a rod and the blocking element is a flat element. The blocking element is preferably rotatably fastened to a base plate with a joint, the base plate and the blocking element forming parts of a hinge. The hollow shaft is preferably arranged at an angle to the base plate such that the blocking element is blocked by the blocking element in one direction of rotation and deflects the blocking element in the opposite direction of rotation such that the rotation in this direction is not blocked.

The fuse is preferably designed in such a way that the blocking element can be removed or folded away in the lower end position for resetting the frictional connection. The blocking element is preferably part of a hinge and can be folded away to reset the frictional connection.

The advantages of the invention are, in particular, that the blind can be quickly wound onto the winding shaft from any position using the crank. Depending on the reduction ratio for a door-high element, this can be done with only about 14, 21 or 28 turns on the crank. This represents an efficiency that is more than 90% better than known systems. With the help of a freewheel, the crank can be prevented from automatically rotating when the curtain is driven by a motor.

Further goals, advantages, features and application possibilities of the present invention result from the following description of an exemplary embodiment with reference to the drawing. All the features described and/or illustrated form the subject matter of the present invention, either alone or in any meaningful combination, even independently of their summary in the claims or their back-reference.

• 1 ein Kurbelgetriebe mit einem Getriebekörper und einer darin in Eingriff stehenden Hohlwelle zur Aufnahme einer Handkurbel in einer bevorzugten Ausführungsform;
• 2 drei Freilaufringe des Kurbelgetriebes gemäß 1;
• 3 die drei Freilaufringe gemäß 2 hintereinander angeordnet;
• 4 einen Freilaufmitnehmer für einen Antriebsmotor;
• 5 einen Adapter für den Freilaufmitnehmer gemäß 4;
• 6 eine drehrichtungsgebundene Sicherung für eine Kurbelwelle in einer sperrenden Stellung;
• 7 die drehrichtungsgebundene Sicherung gemäß 6 in einer nicht-sperrenden Stellung;
• 8 ein Scharnier;
• 9 ein Kurbelgetriebe mit der drehrichtungsgebundenen Sicherung gemäß 6 in einer sperrenden Stellung; und
• 10 ein Kurbelgetriebe mit der drehrichtungsgebundenen Sicherung gemäß 6 in einer nicht-sperrenden Stellung.

Show it:

• 1 a crank gear with a gear body and a hollow shaft engaged therein for receiving a hand crank in a preferred embodiment;
• 2 three freewheel rings of the crank gear according to 1 ;
• 3 the three freewheel rings according to 2 arranged in a row;
• 4 a freewheel driver for a drive motor;
• 5 an adapter for the freewheel driver according to 4 ;
• 6 a directional lock for a crankshaft in a locked position;
• 7 the directional fuse according to 6 in a non-locking position;
• 8th a hinge;
• 9 a crank gear with the directional lock according to 6 in a blocking position; and
• 10 a crank gear with the directional lock according to 6 in a non-locking position.

Identical parts are provided with the same reference symbols in all figures.

a in 1 Crank gear 2 shown comprises a gear base 4, which is firmly connected to a mounting plate 6 or formed in one piece. The fastening plate 6 preferably has fastening openings (not shown) with which the crank mechanism 2 can be fastened, for example, to a wall of a roller shutter box, not shown, or to a building wall or the like. The crank mechanism 2 is designed to wind up a curtain again in an emergency or in the event of a power failure, for example in order to release an escape route or an opening. The curtain can be adjusted between an upper end position and a lower end position, with the lower end position being fully extended. Examples of such a hanging are, for example, blinds, shutters or awnings.

A hollow shaft 8 is guided laterally into the gear base 4 and is connected to a pinion (not shown) which is arranged inside the gear base 4 . The hollow shaft 8 is designed to accommodate a hand crank, in particular in a non-positive manner. The crank gear 2 includes a gear body 12, on which at its end, which is arranged in the gear base 4, a ring gear is arranged (not shown), in which the pinion engages. In this way, the hollow shaft with the pinion and the gear body 12 with the ring gear are designed as a bevel gear 10 . With the gear base 4, a cylinder socket 16 is firmly connected, on which the gear body 12 is rotatably mounted. A winding shaft bearing 14 is rotatably arranged on the cylinder socket 16 and can be connected to a winding shaft (not shown) which is used to wind up and unwind a hanging, for example a curtain or a roller shutter.

In normal operation, the winding shaft is driven by a drive motor (not shown), which is driven by a freewheel driver 18 (see 4 ) is connected to the winding shaft.

The crank mechanism 2 is equipped to prevent the hand crank from turning when the winding shaft is driven by the drive motor. For this purpose, the crank gear includes a freewheel 20 with a plurality of freewheel rings 22-38, which are arranged one behind the other in an axial direction of the gear body 12 or of the cylinder socket 16.

In 2 are an example of three freewheel rings 22, 24, 26 of the freewheel 20 shown in an exploded view. The freewheel ring 22, 24, 26 has an annular body 22a, 24a, 26a and a nose 40, 42, 44 on the circumference or on its outer diameter, which protrudes in an axial direction 50 beyond the annular body 22a, 24a, 26a. In the assembled state, the axial direction also corresponds to an axial direction of the transmission body 12.

The three freewheel rings 22, 24, 26 are in the assembled state in which they are arranged in the crank mechanism 2 3 shown. The lugs 40-44 and the heights, ie the extensions in the axial direction 50, of the freewheel rings 22-26 are designed such that when the freewheel ring 22 rotates, its lug 40 abuts the lug 42 of the freewheel ring 24 arranged adjacent in the axial direction 50 , but not against the lug 44 of the freewheel ring 26. This means that a lug of a freewheel ring abuts during one revolution only against the lug of the respective freewheel ring that is directly adjacent in the axial direction 50.

This provides the following functionality: When the in 3 If the freewheel ring 22 shown rotates clockwise, after almost a full rotation its lug 40 will hit the lug 42 of the directly adjacent freewheel ring 26. If the freewheel ring 22 is now rotated further in the same direction, the two freewheel rings 22, 24 rotate synchronously until the Nose 42 against the nose 44 against the third freewheel ring 26 abuts. Now all three freewheel rings 22, 24, 26 rotate synchronously in a clockwise direction. In this way, a driving movement or dragging movement of two directly adjacent freewheel rings 22, 24, 26 is realized, with the freewheel ring 22 taking the freewheel ring 24 with it in the example described, which in turn takes the freewheel ring 26 with it.

Equivalently, if the direction of rotation is reversed, idler ring 40 will now rotate first, then idler rings 40, 42 will rotate synchronously until all three idler rings 40-44 rotate in the same direction.

This is equivalently true when the one-way ring 44 is being driven. It then first takes the freewheel ring 42 with it in a synchronous manner, then the freewheel ring 40 is taken along, so that all three freewheel rings 40, 42, 44 rotate synchronously.

With the help of the freewheel rings 22-38, a freewheel 20 of the hollow shaft 8 or a hand crank attached thereto is now achieved in the crank mechanism 2 during engine operation. For this purpose, the freewheel ring 22 , which is arranged closest to the gear base 4 , is rigidly connected to the gear body 12 or the gear body 12 has a driving area for the lug 40 of the freewheel ring 22 . The winding shaft bearing 14, which is arranged adjacent to the freewheel ring 38, has a driver area 60, which is preferably designed as a recess in the winding shaft bearing 14 and in which the lug 44 of the freewheel ring 38 can move circumferentially over a predetermined angular range when assembled.

When the drive motor rotates the winding shaft bearing 14 and thus the winding shaft, the freewheel rings first rotate until all the freewheel rings rotate synchronously. At this point in time, there is only a frictional connection between the hollow shaft 8 or crank and the winding shaft. The frictional connection thus takes place only after freewheeling, which can include whole revolutions and/or fractions of revolutions.

The freewheel rings 22-38 are selected in terms of their height, number and circumferential extension of the lugs 40-44 such that this frictional connection between the crank and the winding shaft is only achieved when the blind has reached the lowest end position. This is preferably set automatically the first time you go down, so that the connecting rod no longer rotates when the curtain is moved to its end position. Since the frictional connection between the crank and the winding shaft is achieved after the winding shaft has been actuated via the crank gear 2, this is not broken when the motor moves down and the crankshaft (rod) rotates with it. Thus, the power shot is guaranteed in the lower end position.

The drive motor includes a brake and the blind is held in the desired position by the brake of the drive motor. If the blind is between the upper and the lower end position and has to be wound into the upper end position using the crank, the path covered by the drive motor is first rotated with the crank to restore the frictional connection.

The drive motor is connected to the winding shaft using the in 4 illustrated freewheel driver 18 in the up direction and the adapter 58 coupled. The freewheel driver 18 can only be rotated in one direction, in this case as in 4 shown clockwise. Rotation in the opposite direction is not possible.

Normally, the curtain is moved to the desired position with the help of the drive motor. In an emergency, the curtain, which in the lower end position blocks an escape route, for example, can be raised using the crank. It should be avoided that the crank is turned in the wrong direction. For this purpose, a crank safety device 64 is preferably arranged in the region of the joint bearing, which only allows the crank to be turned in one direction in which the curtain is moved to the upper end position. In 5 an adapter is shown as an example, with the help of which the freewheel driver 18 can be plugged onto a motor.

In 6 a joint bearing 96 is shown, which is inserted into the hollow shaft 8 with an output rod 84 . A universal joint 86 (only indicated) is arranged opposite, to which the actual connecting rod is attached. The joint bearing essentially consists of three parts, namely a joint bearing plate 82, the output rod 84 and the universal joint 86.

The output rod 84 is inserted through the joint bearing plate 82, and the universal joint 86 is pushed onto its end and connected by means of a spring pin. The spring pin has the same length as the receiving body of the universal joint 86 for the driven rod. This is replaced by a longer rod or a blocking element 66 which protrudes on one side. A locking element 62, which is mounted on a base plate 74 of a hinge by means of a joint 70, permits rotation in only one direction (counterclockwise) and locks it, as in FIG 6 shown, clockwise. The blocking element 66 then pushes the locking element 62, which is designed as a leg of the hinge 72, which 72 moves away to the right; on the opposite side, this spring pin prevents rotation. During the reset run, the arm or the blocking element must be folded away so that the safety device does not block the motor.

The blocking element 66 and the hinge 72 with the locking element 62 form a rotationally bound safety device 64 or crank safety device. The blocking element 66 is rigid with the hollow shaft 8 ver bound and is blocked by the blocking element 62 when the crank is turned clockwise. The blocking element 62 can be folded away with the aid of the joint 70 (in particular to enable the reset movement), so that the directional locking is canceled, which is relevant for resetting the frictional connection in the lower end position. In another preferred embodiment, the twist-lock safety device 6464 can also be removed in order to restore the frictional connection in the lower end position of the curtain.

In 7 Pivot bearing 96 and lock 64 are shown in a counter-clockwise rotation position and rotation is free and not blocked by the interaction of blocking member 66 and blocking member 72. The pin-shaped blocking element 66 folds away to the side when it comes into contact with the blocking element 72 so that rotation is possible.

In 8th the hinge 72 is shown in plan view. The locking element 62 is attached by means of the joint 70 to the base plate 74, which preferably has openings 76 for attachment to a ceiling element. The base plate 74 is preferably attached in a horizontal position, so that the blocking element 62 hangs down vertically. In the preferred embodiment shown, the blocking element 62 has an essentially rectangular end region 90 adjacent to a widening region 92 which widens symmetrically with two inclined flanks in the direction of the joint 70 .

In the 9 the joint bearing is shown in a position as it is fastened, for example, to a ceiling element or a ceiling. The position in 9 corresponds to the locked position 6 . When the hollow shaft rotates clockwise, the blocking element 66 strikes the vertically hanging blocking element 62 and is prevented from rotating further. In this way, clockwise rotation is blocked or blocked.

In 10 After a counter-clockwise rotation, the blocking element 66 is located behind the blocking element 62 in the viewing direction realized in the figure and deflects it laterally during the rotation of the hollow shaft 8, as is shown in 7 is recognizable. This allows counter-clockwise rotation.

Reference List

2

crank gear

4

gear base

6

mounting plate

10

bevel gear

8th

hollow shaft

12

gear body

14

winding shaft bearing

16

cylinder socket

18

freewheel driver

20

freewheel

22-38

freewheel rings

22a-26a

ring body

40-44

nose

50

axial direction

58

adapter

60

take away area

62

blocking element

64

rotary fuse

66

blocking element

70

joint

72

hinge

74

base plate

76

openings

82

joint plate

84

output rod

86

universal joint

90

end area

92

expansion area

96

pivot bearing

Claims (7)

Crank gear (2) for an electrically driven curtain, comprising a bevel gear (10) with a gear base (4) in which a hollow shaft (8) connected to a pinion is guided, in the opening of which a hand crank can be inserted, and with a gear body ( 12), which has a toothed ring arranged at the lower end of the gear base (4), in which the pinion engages, with the crank gear (2) behind the end of the gear body (12) facing away from the gear base (4) having a winding shaft bearing (14) for a Winding shaft for winding and unwinding the curtain, and wherein the bevel gear (10) has a reduction ratio in the range of 2: 1 to 4: 1, wherein between the winding shaft bearing (14) and gear body (12) a freewheel (20) with a plurality of freewheel rings (22-38) arranged one behind the other in the axial direction of the gear body (12), each with one circumferentially in the axial direction of the gear body (12) extending lug (40-44) is provided, and one of the freewheel rings (22-38) is coupled to the gear body (12), wherein in the assembled state two lugs (40-44) of block adjacently arranged freewheel rings (22-38) in the direction of rotation, with the winding shaft bearing (14) comprising a driving area (60) for one of the lugs (40-44) of the freewheel ring (22-38), which prevents the relative radial movement between the freewheel ring (22 -38) and winding shaft bearing (44). Crank mechanism (2) after claim 1 , whereby the number of freewheel rings (22-38) and/or the width of the lugs (40-44) is selected in such a way that after a specified number of revolutions of the gear body (12), a non-positive connection of the hollow shaft (8) and winding shaft bearing (14 ) arises. Crank mechanism (2) after claim 1 or 2 , comprising a crank lock (64) which allows the crank to rotate in only one direction of rotation. Crank mechanism (2) after claim 3 , The crank safety device (64) being designed in such a way that it can be removed and/or folded away in a lower end position of the curtain. Operating device for a curtain, comprising a crank gear (2) according to one of the preceding claims, further comprising a drive motor connected to the gear body (12). operating device claim 5 , wherein the drive motor is coupled to the gear body (12) by a freewheel driver (18). operating device claim 5 or 6 , wherein the drive motor has a brake, by which the winding shaft bearing (14) is rotationally fixed.

Images