GB2219039A

GB2219039A - Door drive

Info

Publication number: GB2219039A
Application number: GB8912031A
Authority: GB
Inventors: Peter Andrae; Norbert Kaiser
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1988-05-27
Filing date: 1989-05-25
Publication date: 1989-11-29
Anticipated expiration: 2009-05-25
Also published as: FR2632007A3; GB8912031D0; CH678964A5; FR2632007B3; DE8806956U1; GB2219039B; IT216596Z2; IT8921111V0

Description

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Door Drive .DTD:

Prior Art .DTD:

The invention starts from a door drive according to the precharacterizing clause of the main claim. A drive of this type for a motoractuated garage door is known from DE-OS 2,815,997, for example. This Patent Specification discloses an arrangement in which a rope tensioned at both ends, and serving as a drive device, serves as a supporting and retaining device on the one hand and is looped round a pulley coupled to the drive motor to transmit the movement forces on the other hand. The drive is coupled articulately to a door leaf pivotable about a horizontal axis and slidable transversely to the latter, so that the treck with the motor drive can transport the garage door into a closed position and an open position depending upon the direction of rotation of the motor. A geared small motor, such as is used as a windscreen wiper motor in motor vehicles, for example, serves as drive motor. The rope pulley is arranged directly on the output shaft of the geared small motor. In order to tension the rope it is anchored firmly on the one side and fastened with interposition of a helicoidal spring stressed in tension on the other side, which compensates production tolerances in the Length of the rope on the one hand and obviates any retensioning on the other hand. The limit cut-out of the drive in the open position and in the closed position, like the emergency cut-out, occurs through a camactuated microswitch, the switch cams are adjustable by longitudinal sliding and actuate the microswitch due to a forward movement of the truck.

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An electromechanical garage door drive is known from DE-OS 3,546,282, in which a chain retained resiliently at both ends in a guide rail serves as a positive drive device. In order to move the garage door, the drive motor engages releasably and positively by a pinion into the chain tensioned parallel to the guide rail. Due to the resilient fastening of the chain at both ends, it is slidable resiliently in both directions of movement of the drive motor. This movement is utilized to actuate a limit switch, namely both in the limit positions of the motor-driven carriage and also in the case of a locking of the drive and of the obstruction cut- out.

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Advantages of the Invention The door drive according to the invention having the characterizing features of the main claim possesses the advantage that a highly precise control of the movement of the drive carriage is made possible with simple means. It is cheap to produce and can also be installed and adjusted without difficulty by non-specialists. The door drive according to the invention also generates little noise and requires a low installation height.

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Advantageous further developments and improvements i of the door drive disclosed in the main claim are possible -by the measures enumerated in the subordinate claims. Due to the mode of tensioning of the chain used as a propulsion element, the Latter is retained substantially rigidly, stationary and securely against twisting, and slight pro- ) duction tolerances and expansions are nevertheless compensated.

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A particularty simple decoupling between drive motor and propulsion element, particutarty a drive chain, is obtained by the pivotable assembly of the drive motor in i the carriage. In the working position the drive motor is locked in a particularly simple manner by a resilient strap; in order to release the coupling between drive motor and propulsion element the rigid coupling can be released in a simple and rapid manner by slight resilient deflection of the locking strap, so that the carriage with the door is freely transportable.

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The control device for the drive is also conveniently fastened on the profile rail slidably in the longitudinal direction. A short transport length, and a positioning of the control device adapted to the existing installation conditions, are obtained by this means.

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The contacting and power supply of the drive motor is achieved particularly simply by the arrangement of two mutually insulated sliding contact tracks on the profile rail, on which carbon brushes retained on the carriage slide as current collectors for the drive motor. The insertion of an intermediate part made of insulating material between the two sliding contact track sections of the profile rail permits a simple and reliable mode of contacting whilst maintaining a compact and stable construction of the profile rail.

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The number of components required for the door drive can be further reduced because one and the same terminal piece can be used as a retaining and fastening part at both longitudinal ends of the profile rail. The terminal piece serves both for the positive retention of the profile rail and chain, and also to fasten them in a wall section or ceiling section.

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An exemplary embodiment of the invention is shown in the drawing and explained more fully in the following description. In the drawing Fig.1 shows a general view of the door drive, Fig.2 shows in elevation the top side of the drive carriage facing the profile rail, and 35 Fig.3 shows a section through the profile rail.

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Description of the Exemplary Embodiment .DTD:

In Fig.1, 10 designates a profile rail which is fastened, at Least in the region of its ends, to a ceiling 11a or a wall surface 11b of a garage. Additional fastening points along the ceiling are possible, as may be seen at 11c.

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A chain 12 is tensioned in the profile rail 10. It is pretensioned at one end on a screw bolt 13 by means of a helicoidal compression spring 14; at the other end the chain 12 is tensioned firmly by means of a bolt 15 which is placed in a terminal piece 16. An aperture 17 for the passage of the chain 12, in which the chain is guided positively and securely against twisting, is further pro vided in the terminal piece 16. A similar terminal piece 16 is provided in mirror image relationship at the opposite end of the profile rail 10 and-braces there the screw bolt 13 which retains the chain 12. The terminal pieces 16 also each have a transverse bore 16a to receive a fastening screw 16b by which the terminal pieces 16, and with them the profile rail 10, can be fastened to any desired support means or wall surface.

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A carriage 18 made of plastic is mounted slidabLy on the profile rail 10 and engages by flange-like proj ections 19a,19b into corresponding guideways 10a,10b of the profile rail 10 (Fig.3).

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A small direct-current motor, such as is known for the drive of windscreen wipers in motor vehicles, for ex ample, is mounted as drive motor 20 on the carriage 18. The drive motor 20 is coupled directly by a shaft 22 to a pinion 24, which is in positive engagement with the chain 12 during service. The carriage 18 is coupled by a rod 28 (sic) to a garage door 28, the rod 26 being articulated in the top region of the door 28 and pushing the garage door 28 in the opening or closing direction when the motor 20 is started in known manner.

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A control device 30 for the door drive is also re tained slidabLy on the profile rail 10. It contains, although not shown in the drawing, particularly an elec tronic control unit for the drive of the motor 20, a trans former to reduce the mains voltage to the service voltage of the drive motor 20, an associated rectifier arrangement and a light source which is switched on automatically when the door drive is actuated. The control device 30 is anchored on the profile raiL 20 by means of screws 31; these screws are loosened for transport and for positioning the control device.

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Fig.2 shows a plan of the top side of the carriage 18 which faces the profile rail 10..This figure shows the flange-Like projections 19a and 19b with which the carriage engages behind corresponding guideways 10a and 10b of the profile rail 10 and is thus retained and guided conductively on the rail 10. A permanent magnet 32 for the actuation of a reed switch 33 visible in Fig.3 is fastened to the carriage 18 directly on its surface at one end. The magnet 32 has a right-angled configuration and is dimensioned in the longitudinal direction of the carriage so that the reed switches which it controls can be actuated reliably. The reed switch 33 visible in Fig.3 is anchored by a retaining screw 34 in a recess 35 of the profile rail 10. The retaining screw 34 engages into a separate cavity 36 of the profile rail 10. Space is also Left in the recess 35 fir electrical supply Lines, not shown, to the reed switch.

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In Fig.2 the drive motor 20 is covered by a plate 37 upon which it is fastened pivotably. A pivot screw fastening with a screw 38a.at the pivot point and a screw 38b as fixing means in a slot 39 permits the drive comprising motor 20, shaft 22 and pinion 24 to be slid in the plane'of the drawing so that the pinion 24 comes into positive engagement with the chain, not shown in Fig.2. This position is shown in Fig.2. The Locking of the plate 37 occurs by means of a strap 40 which is constructed as a resilient tongue, engages a shoulder -41 of the plate 37 in the relaxed state and Locks the Latter between pinion 24 and chain 12 in the engaged position. After the strap 40 is pivoted at right angles to the plane of the drawing, by means of a Bowden cable (not shown) or of an unlocking Line, for example, the plate 37 can be slid in the plane of the drawing according to the dimension of the slot 39, the pinion 24 moving out of engagement with the chain 12.

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The carriage 18, and the door 28 with it, are then sLid able manuaL.Ly.

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A brush holder 42, which is also shown in Fig.2, houses carbon brushes 43 and 44, through which the drive motor 20 receives its supply of electrical power. The associated contact surfaces for the carbon brushes 43 and 44 are designated 43a and 44a in Fig.3. The contact surface 44a forms the earth lead, the contact surface 43a serves to connect- the supply voltage. For this purpose a separate rectangular hollow aluminium profile 45 is fastened, electrically insulated by a plastic insulator 46, to the profile rail 10. The insulator 46 has, at each of its two ends, two notched grooves into which corresponding projections on the profile rail 10 and on the aluminium profile 45 engage.

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Fig.3 shows the form of the profile rail 10 in all details. In particular, the guideways 10a and 10b in which the flange-like projections 19a and 19b of the carriage engage are clearly visible. The guideway 10a contains, covered by a lip 47 on the profile rail 10, the projection 10a and also the chain 12, so that the latter is arranged protected and reliably guided. The arrangement is made so that the flange-like projections 19a,b are respectively in contact with the floor of the guideways 10a,b, the chain 12 is located at the inner wall of the projection 19a and is also covered in its full width by the lip 47.

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The reed switch 33 is arranged in the recess so that it is directly adjacent to the permanent magnet 32 which slides past, so that virtually only the thickness of the aluminium profile rail 10 acts as an air gap between reed switch and associated actuating magnet. This ensures correct actuation of the reed switch. Only one reed switch 33 is visible in Fig.3 of the drawing; actually one such reed switch 33 is arranged in each of the two Limit positions of the carriage 18 which correspond to the two limit positions of the door 28.

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The arrangement explained with reference to Figs.1 to 3 is designed for the drive of a garage door, however the application of the invention is not limited to this purpose. Any other comparable doors or flaps may be moved with the same drive. A small direct-current motor with permanent magnet excitation is used as a drive in the exemplary embodiment. This is particularly suitable for the present application due to its simple and robust construction, due to its high starting torque, its freedom from maintenance and its design for safe low-voltage direct current. However, other electric motor drives may also be used depending upon the application and other conditions.

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A carriage sliding in the aluminium profile rail is used as a support for the drive motor and the associated components in the exemplary embodiment. A construction of this type is particularly simple and cheap, if necessary a roller bearing or ball bearing support may also be used instead of the carriage used, if lower friction forces are desired. Instead of the chain used as a drive device, other straight drive parts may also be used, a rack or a screwthreaded spindle for example, however in the present application a chain provides the most advantageous solution for constructing a substantially stationary propulsion element with precisely adjustable switching points. The extruded aluminium profile used can be produced simply and cheaply in virtually any desired configuration and requires no finishing treatment, neither to produce additional profiling nor as protection from corrosion or the like. The arrangement shown permits the construction of a cheap, easily assembled garage door drive which is particularly suitable for fairly light doors. The door drive generates little noise and can be installed as a compact arrangement in standard garages with little height clearance between top edge of door and ceiling.

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During service the drive motor 20 slides together with the carriage 18 along the aluminium shaped profile rail, which is fastened to the garage ceiling 11a. The Linear traction required for the movement of the door 28 is transmitted through the motor pinion 24 to the onepiece chain section 12 stationary in the profile. Little installation height is required due to the horizontal position of the pinion 24 in the carriage 18. The aluminium profile rail 10 used provides adequate rigidity with low weight and small overall height and permits the construction of convenient supporting and sliding surfaces for the forces which occur on the carriage 18. The rail has a largely symmetrical construction with internally located concealed chain for optical considerations.

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Claims

Claims .CLME:

1. Door drive, particularly for a garage door, having an electric motor, particularly a low-tension direct current motor, which drives the door in the opening and closing direction, which is retained on a carriage con nected articulately to the door, having a profile rail with profile sections to guide the carriage, to retain for a propulsion element extending in the longitudinal direction of the rail and to supply the electrical drive power for the motor, also having an electrical control device for the door drive, characterized in that the pro pulsion element (12) is arranged substantially stationary in the profile rail (10) formed by an extruded aluminium prof i le.

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2. Door drive according to Claim 1, characterized in that the propulsion element is constructed as a chain (12) tensioned firmly arid securely against twisting at least at one end.

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3. Door drive according to Claim 1 or 2, characterized in that the propulsion element (12) is tensioned adjustably (13,14) in the longitudinal direction at one end.

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4. Door drive according to one of the preceding claims, characterized in that the drive motor (20) is retained pivotably in the carriage (18) on a base plate (37) in the direction of engagement of motor pinion (24) and propulsion element (12).

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5. Door drive according to Claim 4, characterized in that the base plate (37) is lockable in the position of engagement between drive motor (20) and propulsion element (12).

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6. Door drive according to Claim 5, characterized in that the locking means (40,41) between drive motor (20) and propulsion element (12) is formed by a self-engaging strap (40) of the carriage (18) which is unlockable by means of a Bowden cable, Line or the Like.

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7. Door drive according to one of the preceding claims, characterizedin that the control device (30) is fastened on the profile rail (10) slidably in the Longitudinal direction.

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8. Door drive according to one of the preceding claims, characterized in that the profile rail (10) exhibits, for the power supply to the drive motor (20), two sections as sliding contact tracks (43a,44a) for carbon brushes (43,44), one (44x) of which is constructed integrally with the rail (10), whereas the second sliding contact track (43x) is formed on a profile section (45) retained insulated (46).- on the profile rail (10).

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9. Door drive according to Claim 8, characterized in that the profile section (45) for the second contact sur face (43x) is connected to the profile rail (10) by an insulator moulding (46).

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10. Door drive according to one of Claims 1 to 7,charac terized in that the profile rail (10) exhibits two sections as sliding contact tracks (43a,44a) for the power supply to the drive motor (20).

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11. Door drive according to one of the preceding claims, characterized in that one and the same terminal piece (16) is arranged as a retaining and fastening part in mirror image relationship for the rail (10) on the one hand and for the propulsion element (12) on the other hand at both Longitu dinal-ends of the profile rail (10).

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12. Door drive according to one of the preceding claims, characterized in that the profile rail (10) exhibits a recess (35) for the housing and fastening of limit contact switches (33) in its upper region remote from the drive motor (20).

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13. A door drive substantially as herein before, described with reference to the accompanying drawings.

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Published 1989 atThe Patent Office, State House, 88!71 High Holborn,I. ondon WClR 4TP.Farther copies maybe obtained from The Patent Office. Sales Branch, St Mary Cray, Orpington, Kent BR5 3RD. Printed by Multiplex techniques ltd, 8t Mary Cray, Kent, Con. 1187