WO2005033464A1

WO2005033464A1 - Quick connection tubular motor

Info

Publication number: WO2005033464A1
Application number: PCT/IT2004/000528
Authority: WO
Inventors: Massimo Vigano'; Walter Defendenti
Original assignee: Cherubini Spa
Priority date: 2003-10-03
Filing date: 2004-09-27
Publication date: 2005-04-14
Also published as: ITMI20030459U1; CN1863979A; ITMI20030459V0

Abstract

The present invention relates to a tubular motor for moving awnings, curtains and the like, provided with an output pin adapted to be inserted in the hole of a driving pulley, comprising a resiliant metal element mounted inside the pin or the pulley in such a manner as to cause a protrusion on the pin or on the pulley which hinders the sliding of the pin in the hole of the pulley, suitable to be compressed for allowing insertion and assuming automatically the mounting position when the pin is completely introduced in the hole of the pulley thereby avoiding disengagement of the pin from the pulley.

Description

Title Quick connection tubular motor

Description The present invention relates to a tubular motor for the movement of awnings, curtains and the like, provided with an output pin adapted to be inserted in the hole of a driving pulley. The drawing pulley is usually inserted in the roller tube, for instance, of the awning or curtain; this serves to transmit the movement of the motor from the output pin to the roller tube. The tubular motor is usually inserted in the roller tube. The coupling between the pin and the pulley may be locked in various different ways: by means of one or more screws, by means of a cotter pin, or by means of a Seeger circlip. All of these known means of locking the coupling have a drawback: none of them enables a really rapid connection without the need for tools: the screws have to be screwed in with a screwdriver, the cotter pin has to be inserted with pliers and the Seeger circlips have to be expanded by an appropriate tool. If the pin and/or the pulley are made from plastics material, it is possible to lock the coupling by means of one or more teeth of plastics material (which is therefore partly flexible and resilient). For instance, a tooth is provided directly on the pin while a seat corresponding to the tooth is provided directly on the pulley.

When the pin is coupled to the pulley, the tooth is inserted in the seat and the coupling is locked. However, disengaging the pin and the pulley is then extremely difficult, and may also lead to the breakage of the tooth. Moreover, the service life of plastic teeth is limited. The object of the present invention is to provide a tubular motor with an output pin, having a system for locking the coupling which is rapid, does not require tools, does not impose any constraints as regards the material of the pin and of the pulley (and is therefore adapted to metal pins and pulleys), and can be readily disengaged. The utility of a rapid and simple connection between the output pin of the motor ^'and the driving pulley is readily evident when it is borne in mind that technicians installing (and dismantling) these motors tend to be in relatively uncomfortable and hazardous positions (on top of a ladder, on scaffolding, etc.). The output pin of the motor has to be disengaged from the drawing pulley chiefly when the motor breaks down or, less commonly, if installation has been incorrect. The use of metal materials for the pin and the pulley is always advisable (better resistance to wear, able to transmit greater torques); it will be appreciated, however, that the cost of plastics components is much less than that of metal components. This object is achieved by the tubular motor having the characteristing features set out in independent claim 1. The innovation principle step on which the present invention is based, is that of using a resilient metal member to be mounted within the pin or the pulley in such a way as to cause a protrusion on the pin or on the pulley. Further advantageous features of the present invention are set out in the dependent claims. The present invention is described in further detail in the following description made with reference to the accompanying drawings; these drawings relate to a particular embodiment of the present invention and are not to be understood as limiting: Fig. 1 shows an output pin of a tubular motor according to the prior art; Fig. 2 shows a drawing pulley particularly adapted to the present invention; Fig. 3 shows an output pin of the present invention; Fig. 4 shows a resilient elastic member of the present invention; Fig. 5 shows the pin of Fig. 3 in which the member of Fig. 4 is mounted; Fig. 6 shows the pin of Fig. 5 inserted in the hole of the pulley of Fig. 2; Fig. 7 is a partial section through the assembly of Fig. 6. It should be borne in mind that none of these drawings show all the typical components of a tubular motor; in particular, the electric motor has not been illustrated and only those components which are pertinent to the present invention have been illustrated, primarily the output pin. The output pin of Fig. 1 , according to the prior art, is made in one piece from metal. The head of the pin is solid and has six large teeth. It should be appreciated that tubular motors with many other types of pins, shaped in very different ways, are commercially available. The output pin of Fig. 3, according to the present invention, is very similar to the pin of Fig. 1, but has some major differences: its head is hollow (in this embodiment, the cavity follows the external profile of the head, but this is not essential for the purposes of the present invention) and two holes symmetrical with respect to the axis of the pin are provided vertically with respect to the lateral walls of the head of the pin. The pin of Fig. 1 may be inserted in the drawing pulley of Fig. 2. The pulley has a central shaped hole which substantially complements the shape of the pin. For applications to move awnings or curtains, the presence of play between the pin and the hole of the pulley is not detrimental (provided that it is within reasonable limits). The tubular motor of the present invention is provided with an output pin adapted to be inserted in the hole of a drawing pulley. It comprises a resilient metal member mounted within the pin or the pulley in order to cause a protrusion on the pin or the pulley which prevents the pin from sliding in the hole of the pulley. The resilient metal member is adapted to be compressed to enable the pin to be inserted in the hole of the pulley and is adapted automatically to assume the assembly position when the pin is folly inserted in the hole of the pulley so as to prevent the disengagement of the pin from the pulley. The resilient metal member used in the embodiment shown in the drawings is a piece of suitably shaped harmonic steel wire. An example of such a shaped wire is shown in Fig. 4 prior to mounting within the cavity of the pin of Fig. 3. Fig. 4A shows three orthogonal projections of the member and Fig. 4B shows an axonometric view. Fig. 5 shows the pin of Fig. 3 after the member of Fig. 4 has been mounted therein. The member is disposed almost completely in the cavity of the pin. The ends of the wire project laterally from the two lateral holes of the pin and cause two projections. Two eyelets (produced by bending the wire) project from the front of the pin. The member of Fig. 5, i.e. the piece of wire, is adapted to be compressed in a radial direction by bending. The piece of wire may be compressed until its ends project from the lateral surface of the pin. In this way, the pin may be freely inserted in the hole of the pulley. In practice, the piece of wire is adapted to be even further compressed to enable its mounting within the pin. When the pin is folly inserted in the hole of the pulley, as shown in Fig. 6, the piece of wire automatically assumes (as a result of the resilience of the material), the assembly position, i.e. the position of Fig. 5; in this way, the protrusion caused by the member prevents the disengagement of the pin from the pulley. A number of advantageous, albeit non-essential, aspects of the present invention are described below. The resilient metal member may be made so that it can be manually compressed when the pin is inserted in the hole of the pulley (as shown in Fig. 6).

By manually closing up the two eyelets of the piece of wire, the ends of the piece of wire are retracted in the pin and the pulley may be disengaged without problem. The resilient metal member may be made so that it can be manually compressed when the pin is not inserted in the hole of the pulley (as shown in Fig.

5). By manually closing up the two eyelets of the piece of wire, the ends of the piece of wire are retracted in the pin. This makes it possible (in the case of the embodiment) to mount the resilient metal member and also enables or at least facilitates the insertion of the pin in the hole of the pulley. The resilient metal member may be made so that it is compressed as a result of the insertion of the pin in the hole of the pulley. This characteristic feature has also been used in the embodiment shown in the drawings. Looking at the section of Fig. 7, which corresponds to the situation of Fig. 6, the hole of the pulley has a degree of conicity. In this way, the pin may initially be inserted a few millimetres into the hole, then the walls of the hole start to press on the end of the piece of wire and as the hole contracts, the piece of wire bends and is retracted into the pin. As soon as the wall of the hole ends (and the pin is therefore folly inserted into the pulley), the piece of wire returns to its initial position of protrusion as a result of its resilience. It will be appreciated that the resilient metal member may be made in extremely different ways. Moreover, the protrusion is caused by this member but (in contrast to the embodiment of the drawings) may also be provided by one or more other members separate from the resilient metal member and of the same or a different material. In the case of the embodiment of the drawings, two hoods of plastics material could be applied to the ends of the piece of wire. As an alternative, for example, the resilient metal member could take the form of a conventional helical spring which presses one or a plurality of pins or spheres of metal material. The use of a shaped piece of harmonic steel wire or like material forms a particularly simple, effective and economic embodiment. The use of the openings (at least one) in the pin into which the end of the wire can be inserted to cause the protrusion also forms a particularly simple, effective and economic embodiment. In the embodiment of the drawings, the opening takes the form of a circular hole, but use could also be made of a narrow, elongate eyelet in order better to guide the downward movement of the piece of wire along the opening. In the embodiment of the drawings, two openings and two projections have been preferred. In this way, with a negligible additional cost (a small circular hole), symmetrical operation and a double seal is provided. It will be appreciated that if it were desired to complicate the shape of the resilient metal member, a larger number of holes and protrusions could be provided, for instance six in the case of the drawings. To facilitate manual operations on the resilient metal member, in the case of the piece of wire, eyelets have been provided at the end parts of the piece of wire. Small handles are therefore produced with a negligible cost (two bends in the wire). In the case in which only one protrusion of the piece of wire is provided, a single eyelet could also be sufficient. These are then positioned so that they are accessible on the front of the pin at any time (both prior to, during and after the insertion of the pin into the pulley). As has been illustrated, it may be advantageous for the walls of the hole of the pulley to be conical (at least in part) so as to cause the gradual compression of the resilient metal member when the pin is being inserted into the hole. This is the case in Fig. 2, Fig. 6 and Fig. 7. As can be seen in Fig. 2, only six sections of the inner surface of the hole are conical. To facilitate the compression of the resilient meal member at the beginning of insertion of the pin into the hole of the pulley, it may be provided for the hole of the pulley to have a lip along its perimeter. This lip is shown in Fig. 2 and in Fig. 7.

Claims

1. A tubular motor for moving awnings, curtains and the like, provided with an output pin adapted to be inserted in the hole of a drawing pulley, comprising a resilient metal member mounted within the pin or the pulley so as to cause a protrusion on the pin or the pulley which prevents the pin from sliding in the hole of the pulley, adapted to be compressed to enable insertion and automatically to assume the mounting position when the pin is folly inserted into the hole of the pulley so as to prevent the disengagement of the pin from the pulley.

2. A tubular motor according to claim 1, wherein the resilient metal member is made so that it can be manually compressed when the pin is inserted in the hole of the pulley.

3. A tubular motor according to claims 1 or 2, wherein the resilient metal member is made so that it can be manually compressed when the pin is not inserted in the hole of the pulley.

4. A tubular motor acording to any of the preceding claims, wherein the resilient metal member is made so that it can be compressed as a result of the insertion of the pin in the hole of the pulley.

5. A tubular motor according to any of the preceding claims, wherein the resilient metal member is made from a shaped piece of harmonic steel wire or like material.

6. A tubular motor according to claim 5, wherein the output pin comprises at least one opening and the piece of wire is mounted so that one of its ends is threaded into this opening and causes a protrusion.

7. A tubular motor according to claim 5, wherein the output pin comprises two openings and the piece of wire is mounted such that its two ends are threaded respectively into these two openings and cause two protrusions.

8. A tubular motor according to claims 5, 6 or 7, wherein an eyelet is provided at least at one of the end portions of the piece of wire in order to enable the manual compression of the member.

9. A tubular motor according to any of the preceding claims, wherein the walls of the hole of the pulley are conical so as to cause the gradual compression of the resilient metal member when the pin is being inserted into the hole.

10. A tubular motor according to any of the preceding claims, wherein the hole of the pulley has a lip along its perimeter to facilitate the compression of the resilient metal member at the beginning of insertion.