EP0122629A1 - Electrical driving-device for blinds, curtains or the like - Google Patents

Abstract

Electric driving device for curtains, blinds or the like, having a driving motor (2) in driving relationship with a cable pulley (8) which is provided to be engaged with a cord used to open and close the curtain, and with a device for automatically disconnecting the electric motor in at least one terminal position of the curtain. The present device is characterized in that the disconnecting device has at least one limit switch incorporated in the driving device and detecting if, during the operation of the motor, a stop element arranged on the cord is positioned against a stop. The extension of the cord may thus be neglected.

Description

The invention relates to an electric drive device for curtains, curtains or the like, with a drive motor which is in drive connection with a rope pulley which is designed for engagement with a cord for opening and closing the curtain, and with a device for automatically switching off the electric motor in at least one end position of the curtain.

In a known device of this type, the electric motor is switched off in both end positions of the curtain, if it is not switched off manually, in that a part of the curtain connected to the cord, in particular a roller, at the end of a guide in which the roller slides, comes to the plant, and that the then effective increased torque of the electric motor is used for switching off by means of a torque sensor. The torque required to switch off is considerably greater than the torque required to pull the curtain. The known device has the disadvantage that the increased torque causes the cord to be stretched, that is to say a permanent length extension, as a result of which the shutdown accuracy can be impaired and re-tensioning is necessary from time to time.

The invention has for its object to provide a device of the type mentioned, in which no significantly increased torque of the engine is required for switching off. This object is achieved according to the invention in that the switch-off device has at least one limit switch built into the drive device, which detects when a stop means arranged on the cord comes to rest against an associated stop when the motor is running.

The stop element can in particular act directly on the limit switch, which can thus form the stop itself, or, as is provided in the embodiments described later, a movably mounted stop is provided which transmits its movement to the switching element of the limit switch. Another embodiment that is possible in principle will be explained later.

In one embodiment of the invention, the drive device has, in the interior of a housing, a pivotably mounted control shaft which has a radially projecting projection which interacts with the switching element of the limit switch. In this case, a further radially projecting projection can be provided on the control shaft, which forms the abovementioned stop. The advantage of such a control shaft is that the limit switch can be placed in a location of the drive device that is suitable for constructional reasons and that can be located relatively far from the stop.

In one embodiment of the invention, the control shaft runs within a bore in the motor shaft, and the limit switch is arranged in the region of that end of the control shaft that lies on the side of the motor facing away from the stop. An advantage is that the electrical supply lines to the limit switch can be laid parallel to the electrical supply line to the motor without difficulty.

In one embodiment of the invention, a spring is provided for returning the control shaft to a position in which the limit switch is not actuated. This can be useful for electrical reasons. To switch off the motor, a single brief actuation of the limit switch is sufficient.

In one embodiment of the invention, the control shaft is essentially coaxial or parallel to the pulley and has a radially protruding arm closely adjacent to the pulley, such that when the motor is running a stop element attached to the cord comes into contact with the arm and rotates the control shaft. In this case, according to embodiments of the invention, the radially projecting arm can be located on that side of the rope pulley which faces the motor, or else on the other side of the rope pulley. In the latter case, the control shaft extends through a central recess in the pulley.

In one embodiment of the invention, at least one actuating part is slidably guided in the housing, which has an abutment surface protruding from the housing, which is provided for cooperation with an abutment element fastened to the cord, and which has its end region which is located inside the housing and faces away from the abutment surface actuation of the limit switch. It is thereby achieved in a particularly simple manner that the limit switch arranged in the interior of the housing is actuated safely without it being necessary for the stop element arranged on the cord to be able to run into the interior of the housing. According to embodiments of the invention, the actuating part can be designed such that the cord can be passed through it. In one embodiment of the invention, the inner end of the operating part acts on the arm mentioned above. In another embodiment of the invention, the inner end region of the actuating part acts directly on a switching element of the limit switch. The limit switch can be arranged in close proximity to the rope pulley. The advantage of this embodiment lies in the space-saving construction. If, as in the exemplary embodiment, the limit switches are located in a housing part which is separate from the actual motor housing, the motor can be easily removed from the latter housing part, the The number of connections to be disconnected and re-established after replacing the motor is limited to the power supply to the motor. This makes maintenance and repair of the device easier.

In one embodiment of the invention, the control shaft is designed for anchoring to a part of a curtain rail, such that the stator of the motor can be pivoted to a limited extent with respect to the control shaft. The advantage is that the stop element arranged on the cord of the curtain does not now have to interact with a special stop of the drive device which is designed to be pivotable relative to the housing of the drive device, but that it is sufficient that the cord in any end position of the curtain, for example, when a roller hits the end of the curtain track. The motor which is still running then causes the stator of the motor to pivot somewhat, as a result of which the limit switch, which is immovable relative to the stator, rotates relative to that in the adjacent end of the likewise immovable control shaft, so that the limit switch is actuated. This embodiment is particularly advantageous when curtain rails are used with an extremely low height, so that it would be difficult to make the arrangement so that a stop element arranged on the cord can enter the drive device in order to pivot the control shaft.

• Fig. 1 einen Längsschnitt teilweise abgebrochen, durch eine Antriebsvorrichtung für Vorhänge,
• Fig. 2 eine Ansicht auf die Vorrichtung nach Fig. 1 von links,
• Fig. 3 eine der Fig. 2 entsprechenden Ansicht, jedoch bei abgenommenen Deckel,
• Fig. 4 eine Ansicht entsprechend der Linie IV-IV auf die Endschalter.
• Fig. 5 eine Ansicht, teilweise abgebrochen, in Richtung des Pfeils V in Fig. 3,
• Fig. 6 eine Seitenansicht, teilweise abgebrochen und im Längsschnitt, durch einen Teil einer weiteren Antriebsvorrichtung für Vorhänge,
• Fig. 7 einen Schnitt entsprechend der Linie VII-VII in Fig. 8 durch den auf das in Fig. 6 gezeigte Teil links aufsteckbaren Vorrichtungsteil und
• Fig. 8 eine Ansicht von links auf den Vorrichtungsteil der Fig. 7, bei dem jedoch einige Teile entfernt sind.

Further features and advantages of the invention will become apparent from the following description of embodiments of the invention with reference to the drawing, which shows details essential to the invention, and _'from the claims. The A Individual features can be implemented individually or in any combination in any combination in one embodiment of the invention. Show it:

• 1 is a longitudinal section partially broken off by a drive device for curtains,
• 2 is a view of the device of FIG. 1 from the left,
• 3 is a view corresponding to FIG. 2, but with the cover removed,
• Fig. 4 is a view along the line IV-IV on the limit switch.
• 5 is a view, partially broken away, in the direction of arrow V in Fig. 3,
• 6 is a side view, partially broken away and in longitudinal section, through part of a further drive device for curtains,
• Fig. 7 is a section along the line VII-VII in Fig. 8 by the part of the device shown in Fig. 6 on the left part of the device and
• Fig. 8 is a view from the left of the device part of Fig. 7, but with some parts removed.

The device has an electric motor 2 which is surrounded on all sides by a motor housing, and to the left (in the view of FIG. 1) there is a first roller housing 4 and a second roller housing 6, which essentially form a housing for a cable pulley 8 which Parts of the device arranged to the right of the motor 2 are covered by a cap 10 which has a feedthrough 12 through which an electrical cable 14 enters the inside of the cap 10, which contains the electrical leads to the electric motor 2 and to limit switches to be explained later.

The inner rotor 16 of the electric motor 2 drives a hollow shaft 18, which is connected in a rotationally fixed manner to the cable wheel 8, the rotationally fixed connection being effected by a tongue and groove connection. If the device for driving a curtain or a curtain shown in FIG. 1 is mounted, the longitudinal direction of the motor shaft 18 runs perpendicularly, and the cable pulley 8 is approximately at the level of the curtain strip guiding the curtain.

The second roller housing 6 has a projection 20 which is intended for engagement in a conventional curtain rail and which serves to mount the device in a defined position relative to the curtain rail. The firm anchoring to the curtain rail is facilitated by a recess 22 in the area of the projections 20. Further recesses 24, which are provided on outwardly projecting projections of the roller housings 4 and 6, are intended to facilitate cladding of the drive device by material webs.

The cable wheel 8 is supported on its side facing the motor 2 by a Seeger ring 26 which engages in a groove in the motor shaft 18, and on the other side the cable wheel 8 is held by two disks 30 and 32, of which the latter disk 32 abuts a lever 36 formed from flat material.

The lever 36 is rotatably attached to a control shaft 38 which is passed through a bore in the motor shaft 18 and is secured by a spring ring 40. At the other end of the control shaft 38 pointing to the right in FIG. 1, an actuating element 44 is connected in a rotationally fixed manner and secured against slipping off by a spring ring 46.

In Fig. 3, in which the pulley 8 is shown partially broken off, the cord 48 drawn into the device is shown.

In the illustration in FIG. 4, the cap 10 is not shown for the sake of simplicity. FIG. 4 shows two limit switches 50 and 52, which are fastened to the end shield 54 of the electric motor 2 on the right in FIG. 1, using suitable spacing elements at the distance shown in FIG. 1 for the limit switch 52. The actuating element 44 has a short arm 56 pointing upwards in FIG. 1, to which an extension 58 running parallel to the control shaft 38 is connected. The end region of the extension 58 lies exactly between the two switching elements 60 of the limit switches 50 and 52. If the control shaft 38 is rotated slightly, the extension 58 actuates the limit switch 50 or the limit switch 52 depending on the direction of rotation. The actuating element 44 has the arm 56 diametrically opposite one another arm 62 of greater length, which also extends radially to the control shaft 38. The arm 62 carries at its free end a transverse bar 64 which extends substantially transversely to the longitudinal direction of the control shaft 38, and the two ends of the transverse bar 64 are in the vicinity of the free ends of a U-shaped leaf spring 66 which is anchored to the end shield 54 is. The leaf spring 66 ensures that the extension 58 is normally not in engagement with the actuators 60 of the limit switches 50 and 52.

In the housing 4, 6, two actuating parts 67, which cooperate with the lever 36, are mounted so that they can be displaced from the bottom to the top in the illustration in FIGS. 1 to 5. The actuating parts 67 have a tubular section 68 protruding from the housing 4, 6, the inside diameter of which is so large that the cord 48, which is passed through the tubular section 68, passes through almost without friction, but that one on the cord 48 attached stop element 69, in particular a precursor which is held on the cord by means of a screw, does not fit through. In the interior of the housing 4, 6, on the side of the actuating parts facing away from the tubular section 68, a strip-like projection 70 is arranged, which in the illustration in FIG. 5 is laterally moved out of the longitudinal central plane of the tubular section 68 perpendicular to the plane of the drawing so that it is a small distance from the cable wheel 8 and its end 71 is normally at a distance from the lever 36, as shown in FIG. 3. The connection between the strip-like projection 70 and the tubular section 68 is established by a center piece 72 with a square outer cross section. This creates a safeguard against that the actuating parts 67 can rotate about their longitudinal axis, which corresponds to the direction of the cord passing through them.

If the sheave 8 rotates counterclockwise in the illustration in FIG. 3, then depending on the location at which the stop element 69 is fastened to the cord, this stop element 69 comes on the outer end face 73 of the stop element on the right in FIG. 3 3 and moves the actuating element 67 in FIG. 3 upward, so that it finally comes to bear against the lever 36 and this and thus also the control shaft 38 is pivoted in the counterclockwise direction, through which the extension 58 is pivoted and thereby the Limit switch 50 is actuated. As soon as the engine is switched off, the leaf spring 66 brings the actuating element 64 back into the position visible in FIG. 4. If the actuating part 67 is in a position delimited by the housing 4, 6, the most outward, that is to say shifted downward in FIG. 3, the distance between the end 71 and the lever 36 is so large that if the other actuating part 67 is moved by the stop element 69, the pivoting angle of the lever 36 is sufficiently large to actuate the limit switch 50 or 52. A stop element, not shown in FIG. 3, arranged on the left strand of the cord 48 comes to rest on the actuating part 67 on the left in FIG. 3 when the rope pulley 8 runs and then causes the limit switch 52 to respond.

To thread the cord, the housing part 4 can be removed after loosening screws, and if necessary, after loosening the spring ring 40, the rope wheel 8 can also be pulled out in order to be able to insert the cord more easily.

A capacitor that is required for operating the electric motor 2 can also be seen in FIG. 1 within the right-hand part of the cap 10. The connections 53 of the limit switches 50, 52 are connected to the cable 14. The individual components of the device shown in Fig. 1 are clamped together by means of long screws.

The part 101 of a further drive device for curtains shown in FIG. 6 has a motor housing 103 in which the electric drive motor of the device is arranged. The motor drives a planetary gear 105, of which only a few parts are broken off, drives a shaft 107, which has longitudinal teeth in its left end region 110 in FIG. 6, so that it can be rotatably engaged with the pulley described later . An electrical multiple coupling 114 is fastened in a housing part 112 which is extended downward relative to the motor housing 103 and to which a multiple plug 116, which is connected to an electrical cable for supplying power to the motor, can be connected. The electrical lines 118 leading to the motor lead partly to an electrical clamping device 120, partly to the multiple coupling 114.

The device part 130 which is arranged on the left-hand side of the housing part 112 in the ready-to-operate state and is arranged immediately after this is shown separately in FIGS. The device part 130 contains a rope pulley 134 which is easily rotatably supported by a ball bearing 132 and over which the pulling rope (not shown) of the curtain is guided. The cable pulley 134 has a central recess with a longitudinal toothing 136 which can be pushed onto the end section 110 of the shaft 107 and is rotatably connected in this way to the shaft 107. Two microswitches 138 and 139 are arranged in the device part 130, each of which has a switching arm 140. Each switching arm 140 can cooperate with the upper end region of a switching pin 142, which is arranged in a housing part 144 of the device part 130 in the illustration in FIG. 8 so as to be vertically displaceable. The switching pin 142 has a groove, into which a spring ring 146 engages, which serves as an abutment for a helical compression spring 148, which is supported with its upper end region on part of the housing part 144. The spring 148 thus endeavors to always move the switching pin 142 into the end position shown in FIG. 8, in which the microswitches 138, 139 are not actuated. The end regions 150 of the switching pins 142 facing away from the microswitches 138, 139 protrude from the housing 144. They are at a distance from the longitudinal center plane of the housing 144, which runs perpendicular to the plane of the drawing in FIG. 8, which corresponds approximately to the deflection radius of the traction cable guided by the pulley 134 and can therefore be displaced into the interior of the housing part 144 by means of a lifting means fastened to the traction cable , so that they operate the respective microswitch 138, 139. For this purpose, the outer end surface of the switching pins forms a stop surface 151.

In Fig. 7, the electrical clamping device 120, which is part of the device part 101, is drawn in the position it occupies relative to the device part 130 when it is attached to the device part 101. Connections of the clamping device 120 are connected to the electrical connections of the microswitches 138, 139.

For the sake of clarity, the cable pulley 134 and the ball bearing 132 and a cover 160 shown in FIG. 7 are not shown in FIG. 8.

The device shown in FIGS. 6 to 8 with the motor axis running horizontally, like the device described with reference to FIGS. 1 to 5, is generally arranged in the installed state in such a way that the motor axis runs perpendicularly, so that the switching pins 142 run horizontally. After loosening a screw connection between the housing part 112 and the housing part 144, the unit shown in FIG. 6 can be pulled off the housing part 144, the end section 110 of the shaft 107 being easily detached from the cable pulley 134. A few electrical connections in the area of the clamping device 120 are then still to be loosened, and then the device part shown in FIG. 6 can be removed, for example in order to carry out an engine repair. The curtain traction cable remains in engagement with pulley 134, which does not have to be removed from the place of the building where it is located to replace the motor.

The reference symbols in the claims are not restricted, but are intended to facilitate understanding.

Claims (11)

1. Electric drive device for curtains, curtains or the like, with a drive motor (2) which is in drive connection with a rope pulley (8, 134), which is designed to engage with a cord (48) for opening and closing the curtain and with a device for automatically switching off the electric motor in at least one end position of the curtain, characterized in that the switching off device has at least one built-in limit switch (50, 52, 138, 139) which detects when the motor is running a stop means arranged on the cord comes to rest against an associated stop (36, 67, 150). 2. Device according to claim 1, characterized in that it has a control shaft (38) which is pivotally mounted in the interior of a housing and which has a radially projecting projection (58) which is connected to the switching element (60) of the limit switch; (50, 52) interacts. 3. Apparatus according to claim 2, characterized in that the control shaft (38) extends within a bore of the motor shaft (18) and that the limit switch (50, 52) is arranged in the region of that end of the control shaft which is on the side facing away from the stop of the engine. 4. Apparatus according to claim 2 or 3, characterized in that a spring (66) is provided for resetting the control shaft in a position not actuating the limit switch. 5. Device according to one of claims 2 to 4, characterized in that the control shaft (38) is substantially coaxial or parallel to the cable pulley (8) and has a radially projecting arm (36) closely adjacent to the cable pulley, such that when Running of the motor (2) a stop element attached to the cord (48) comes into contact with the arm and rotates the control shaft. 6. Device according to one of the preceding claims, characterized in that in a housing (4, 5, 144) at least one actuating part (67, 142) mounted displaceably in its longitudinal direction is arranged, that a stop surface (73, 151) of the actuating part (67, 142) protrudes from the housing, and that the actuating part (67, 142) with its end region (71) facing away from the stop surface effects the actuation of the limit switch (50, 52, 138, 139). 7. The device according to claim 6, characterized in that the cord (48) can be passed through the actuating part (67). 8. Apparatus according to claim 5 and according to claim 6 or 7, characterized in that the actuating part (67) cooperates with its end region (71) facing away from the stop surface with the arm (36). 9. The device according to claim 6 or 7, characterized in that the actuating part (142) cooperates with its end region facing away from the stop surface with a switching element (140) of the limit switch (138, 139). 10. The device according to claim 9, characterized in that the limit switch (138, 139) of the pulley (134) is arranged closely adjacent. 11. The device according to claim 2, characterized in that the control shaft is designed for anchoring to a part of a curtain rail, such that the stator of the motor can be rotated to a limited extent with respect to the control shaft.

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