FR2599524A1 - Device for automatically stopping the winding and unwinding of a windable element - Google Patents

Abstract

Device for automatically stopping an electric motor winding and unwinding a windable element. It comprises two switches 6, 7 each actuated by a movable stop 2, 3 kinematically linked with the windable element. A movable index 8 associated with one of the stops makes it possible to record the displacement of the movable stops between the automatic stop positions desired. A second movable index associated with the other stop makes it possible to transfer the distance recorded by the first index 8 and thus to determine the initial position of the second stop 3 so that the latter actuates the second switch 7 at the desired instant. This device makes it possible to adjust rapidly the automatic stop positions of the windable element in the case where the device is inaccessible when the windable element is wound.

Description

The present invention relates to an automatic stop device for an electric motor ensuring the winding and unwinding of a rollable element, device comprising two switches corresponding respectively to the rolled-up and unwound position of 1 roll-up element and each cooperating respectively with a stop for cut the power supply to the motor when the roll-up element arrives in the rolled-up position. respectively desired course. means for linear drive of the switches or stops, kinematically linked to the windable element and adjustment means per # making it possible to modify the relative position between each switch and its stop regardless of the movement of the windable element.

Such devices are known, for example from the patent
FR 2 076 529, the utility certificate FR 2 497 261 and the patent CH 453 646.

To adjust such automatic stop devices, it is necessary that the adjustment means are accessible when the roll-up element is in the desired automatic stop position. This condition is fulfilled when they equip tubular gearmotors such as that described for example in patent CH 453 646..However, when they equip gearmotors generally called around the "or" central "axis such as that described in the utility certificate FR 2 497 261, the adjustment means can only be accessible when the roll-up element is in the only unrolled position The installer who must adjust the stopping point when the element is wound, of an installation equipped with such a gearmotor, must successively - control the unwinding of the windable element
until it comes to its first position
automatic shutdown or automatic shutdown device
tick is accessible; - act on the means of adjusting the stop device
in order to make an initial arbitrary adjustment of the
second automatic stop point; - order the winding of the element and wait
that it stops automatically; - locate the difference between the position of the element as well
arrested and that desired; - deduct the value of the retouching to be carried out on the
means for adjusting the automatic stop device; - order the element again
can be rolled up so that the automatic stop device
be accessible; - touch up.

The setting of the second automatic stopping point is thus carried out by successive approximations and the preceding operations are repeated as long as the desired result is not obtained. This requires numerous maneuvers, which represents a first drawback.

Otherwise. the electric motors fitted to such geared motors are generally relatively small and highly stressed, because in practice they only operate for very short periods. Also, to avoid excessive overheating resulting from accidental prolonged use, they are equipped with thermal safety automatically limiting the maximum duration of continuous operation. However, this duration is not sufficient when it comes to adjusting the installation according to the procedure described above. The adjustment operation is therefore generally abruptly interrupted, which is another disadvantage.In addition, the installer is obliged to wait for the thermal safety reset, that is to say ten minutes before being able to resume its adjustment, which is yet another drawback.

Finally. when the installer resumes his adjustment at the end of the motor power supply interruption, he may have forgotten the effects produced by the last touch-up which is a source of error or requires an additional cycle to find the last adjustment elements, which is another drawback.

The present invention is able to obviate these drawbacks, that is to say to allow faster adjustment, without interruption.

To this end, the automatic stop device according to the invention comprises an indicator registering the movement of 1 mobile element, respectively of one of the mobile elements, stops or switches. this indicator being kinematically linked to the rollable element, between a first stop position corresponding to the unwound position of 1 rollable element and a second desired stop position corresponding to the rolled position of the rollable element, and means to postpone the movement recorded by the indicator between the other stop and 1 other switch.

The witness can simply be constituted by a movable index capable of being driven in one direction by the movable element whose displacement it must record.

The means for postponing this movement can also essentially consist of a second movable index.

According to certain forms of execution. these indexes move respectively in front of a graduated scale.

According to a preferred embodiment of the invention.

comprising two separate mobile elements moving along two separate axes parallel to each other and in opposite directions for the same direction of movement of the windable element, the two indexes are driven in one and the same direction by the mobile elements and their ends move substantially on the same line and coincide when the two mobile elements are in contact with the fixed elements, the index fingers being in contact with the mobile elements so that the transfer of the path traveled by one of the mobile and recorded by one of the indexes can be executed by bringing 1 other index in coincidence with the first index by means of the mobile element which is associated with it.

This embodiment allows a more precise adjustment than with graduated scales, because the error coming from the reading of the first scale and on the other hand from the transfer to the second scale is eliminated.

 Some embodiments of the invention will be described, by way of example. by means of the attached drawing.

in which FIGS. 1 to 6 schematically represent a first embodiment and the successive phases of the adjustment; FIG. 7 represents a variant of the first embodiment; FIG. 8 represents a second embodiment comprising a single screw on which movable stops are mounted; Figure 9 is an axial sectional view of one of the movable, adjustable stops of the second embodiment; Figure 10 is a sectional view along XX of Figure 9; FIG. 11 schematically represents an alternative embodiment of the second embodiment; Figure 12 is a full axial sectional view of a third embodiment; Figure 13 is an external view of this third embodiment; Figure 14 is a partially sectional view along
XIV-XIV of figure 13; Figures 15 to 19 schematically represent the successive phases of the adjustment of the stopping points of the device shown in Figures 12 to 14; Figures 20 to 25 schematically show a fourth embodiment and its successive positions when adjusting the breakpoints.

The automatic stop device shown schematically in Figure 1 is similar in design to that described in patent FR 2 076 259. It differs from it only by the use of two screws of the same pitch.

It comprises a toothed or grooved shaft 1 kinematically linked in rotation with the enro lable element, two sliding nuts 2 and 3 # in the form of a pinion meshing with the teeth of the shaft 1 and mounted respectively on two screws 4 and 5 parallel to the shaft 1 and which can be manually rotated to adjust the position of the movable stops 2 and 3, a first fixed switch 6 actuated by the movable stop 2 and a second fixed switch 7 actuated by the movable stop 3. The switch 6 is intended to ensure the engine stops driving the windable element in the unwound position of this element, while switch 7 is intended to ensure the engine stops in the wound position of the windable element. device further comprises a first movable index 8 moving on a guide means 9 and intended to be driven in the direction of the arrow by the movable stop 2, but not in the opposite direction, and a second movable index 10 movable along 'a hub n guide 11 and integral, in both directions.

of the movable stopper 3. The index 8 moves in front of a graduated scale 12, while the movable index 10 moves in front of a graduated scale 13. The scales 12 and 13 are identical and the zeros of the scales correspond to the switch actuation positions. The whole is mounted between two flanges not shown and generally housed in a box.

The guide means 9 and 11 may consist of bars or slots in the housing.

The adjustment process of this device will be described in relation to FIGS. 2 to 6. When mounting a roll-up element, the device is for example in the unadjusted position shown in FIG. 2.

The windable element is unwound and the means for adjusting the automatic stop device are accessible. The movable stops 2 and 3 and their indexes 8 and 10 are in any intermediate position.

In this unrolled position, by acting on the screw 4, the movable stop 2 is brought against the switch 6 so as to actuate this switch. The movable index 8 is also brought near the movable stop 2. The movable stop 3 is moved as far as possible from the switch 7 (FIG. 3).

The windable element is then wound up to its desired stop position. During this winding, the mobile stops 2 and 3 are rotated by the splined shaft 1 and move to a certain position (FIG. 4), the mobile index 8 being driven by the mobile stop 2.

The windable element is then unrolled by means of its motor which stops automatically in the desired unrolled position when the mobile stop 2, driven by the splined shaft 1, meets the switch 6. The other mobile stop 3 moves in the same direction as the stop 2, driving its index finger 10, while the movable index finger 8 has remained in the acquired position at the stop position corresponding to the wound position of the windable element (FIG. 5).

To set the second desired stop position corresponding to the wound position of the windable element, it suffices to manually move the movable stop 3 relative to the switch 7, by turning the screw 5, by a distance equal to the displacement of the movable index 8, that is to say of bringing the movable index 10 opposite the same scale, of its scale 13, as the index 8. The automatic stop device is then adjusted, During the next winding of the windable element, the movable stop 3 will actuate the switch 7 in the desired stop position, since it has traveled the same distance as that traveled by the movable stop 2 between the first and the second desired stop position (Figure 6).

In the first embodiment described above, the functions of the stops 2 and 3 and their indexes are differentiated, the movable index 8 being always used as a witness and the index 10 as a means of reporting the distance traveled by index 8. This is no longer the case in the variant embodiment shown in FIG. 7.

In this variant, the mobile stops 2 and 3 'are identical and the mobile indexes 8 and 10' are both movable in one direction, by pushing. Both index 8 and index 10 ′ can be used as a displacement indicator and to report this displacement.

for example the displacement of the index 8, we first bring the stop 3 'and its index 10' to the left of the scale corresponding to the position to be transferred then push the index 10 'by means of its movable stop 3 'opposite this graduation. This variant has the advantage of being independent of the direction of rotation of the motor.

A second embodiment of the automatic stop device according to the invention is shown diagrammatically in FIG. 8. This device comprises a single screw 14 kinematically linked in rotation with the windable element and on which are mounted two movable stops 15 and 16 constituted by two nuts immobilized in rotation by a guide bar 17 (FIG. 10) and cooperating respectively with two fixed switches 18 and 19. The movable stop 15 drives, in one direction, a movable 4index 20 in front of a ladder graduated 21, while the movable stop 16 drives in both directions, a movable index 22 in front of a graduated scale 23. These two movable stops each consist of a cylindrical nut 2; on and around which is mounted a ring 25 retained axially on 1 nut 24 by a circlip 26 and secured in rotation with the nut 24 by means of a radial screw 27.

Regarding the movable stop 16, the movable index 22, slidably mounted on a guide bar 28, is engaged in a housing 29 of the ring 25, without play in the direction of movement of the stop.

The adjustment of the stopping points of this device is carried out in the same way as for the first embodiment with the only difference that the manual movement of the mobile stops 15 and 16 is carried out by slightly unscrewing the screw 27 so to be able to rotate the nut 24 to bring the movable stop. respectively its movable index, in the desired position, then tightening the screw 27.

Figure 11 is a variant of the second embodiment, in which the two movable indexes 20 and 22 'are both drive in one direction so that, as in the case of Figure 7, the movable indexes can both play the role of witness and means of reporting. so that the device is independent of the direction of rotation of the motor.

A third embodiment, which constitutes the preferred embodiment of the invention, is shown in more detail in FIGS. 12 to 14. In principle, this embodiment is very close to the first embodiment shown in Figure 1. It comprises a grooved rotary shaft 31 meshing with two stops 32 and 33 constituted by pinion nuts mounted respectively on screws 34 and 35 corresponding respectively to the shaft 1, to the two movable stops 2 and 3 and to the screws 4 and 5 of Figure 1, The screws 34 and 35 are however of equal and opposite pitch, so that the movable stops 32 and 33 move simultaneously in opposite directions, The assembly is mounted in a tubular housing 39, between a end flange 41 and an inner flange 42. The movable stops 32 and 33 act respectively on lifting beams 36 located in the same plane perpendicular to the screws 34, 35 and 37 actuating the switches located behind the drawing plane and not visible on the drawing. The spreaders 36 and 37 are respectively held in the rest position by springs 43 and 44 working in compression. One end of the shaft 31 is provided with a flange 45 for its coupling to a member kinematically linked in rotation with 1 windable element.

The screws 34 and 35 respectively have an extension 46 and 47 provided with a flat integral in rotation with a conical head 48, respectively 49 provided with a screw slot for its rotation drive by means of a screwdriver, these heads 48 and 49 being rotatably mounted in conical housings at the bottom of the case 39 in which they are held by springs 50 and Si arranged between these heads and the inner flange 42.

On either side of their threaded parts, the screws 34 and 35 have non-threaded constrictions 50, 51, 52 and 53 ensuring the disengagement, for safety reasons. movable stops 32 and 33. At the ends of the screws located on the right in the drawing, the movable stops 32 and 33 abut against springs 54 and 55 ensuring the automatic re-engagement of the stops 32 and 33. These movable stops 32 and 33 respectively drive an index 38 and 40 in one direction. These indexes are guided in slots 71, respectively 72 of the housing 39. The tips of these arrow-shaped indexes move substantially along a common line 57 (FIG. 13). As can be seen in FIG. 14, each index includes a fork 58 surrounding the corresponding screw 34. respectively 35, a part in an arc of a circle situated outside the housing 39 and a part in an arc of a circle 59 situated inside the housing, so that the index finger is perfectly guided by the housing, the corresponding movable stop pushing the index finger by its fork 58.

The adjustment of the stopping points of the device shown in Figures 12 to 14 will be described in relation to Figures 15 to 19. Figure 15 shows schematically the device in its initial position. The windable element is unwound in its first automatic stop position, the adjustment heads 48 and 49 are accessible, the adjustment is not made and the movable stops 32 and 33 are in any intermediate position.

By turning the head 48, the screw 34 is driven so as to bring the movable stop 32 against its switch 36, so that this switch is actuated. The movable index 38 is brought near the movable stop 32. The movable stop 33 is moved as far as possible from its switch 37.

The roll-up element is then rolled up to # its second desired automatic stop position. The index finger 38 is then pushed by the movable stopper 32 to the position shown in FIG. 17. The movable index finger 40 has not moved. In this rolled-up position of the roll-up element, the adjustment heads 48 and 49 are not accessible.

The windable element is then unwound to its first automatic stop position. During this course, the movable stop 32, driven by the splined shaft 31, returns in the direction of the switch 36 and automatically stops the motor in its first stop position when it meets the switch 36. The movable index 38, not driven in this direction, retains its previous position. The movable stop 33 moves in the opposite direction towards the index 40.

In this unrolled position, the adjustment heads 48 and 49 are accessible and it is then possible to move the mobile stop 33 by rotating the head 49. First of all, the mobile stop 33 is moved so as to come beyond the 'index 38 and to also allow to bring 1 movable index 40 beyond the index 38, then we bring in the other - sense the index 40 in front of the index 38 by means of the mobile stop 33 (figure 19). The second automatic stop point is thus set. The use of two equal and opposite pitch screws thus makes it possible to adjust by direct coincidence of the two movable indexes and thus to do without a graduated scale, which has the effect of eliminating the cumulative errors originating from the inaccuracy of the reading. of the first scale and of the carry over to the second scale.

 A fourth embodiment, as well as its mode of adjustment, are shown diagrammatically in FIGS. 20 to 25. Like the second embodiment, this fourth embodiment comprises a single screw 60 kinematically linked # in rotation with the roll-up element. On this screw are mounted two stops 61 and 62 constituted by nuts locked on the screw 60 by means of a screw 63, respectively 64, so that these stops rotate with the screw 60. Between the stops 61 and 62 is mounted on the same screw 60 a movable member 65 in the form of a nut retained in rotation by a guide bar not shown or any other means.

This movable element 65 carries the switches 66 and 67 ensuring the stopping of the drive motor of the windable element. The switch 66 cooperates with the stop 61, while the switch 67 cooperates with the stop 62.

To move the stops 61 and 62 along the screw 60, when this screw is not driven, the stops are released by slightly unscrewing the screws 63 and 6X, which allows to screw, respectively unscrew the stops on the screw 60. The movable element 65 pushes an index 68 and the stops 61 and 62 are respectively provided with a mark consisting of a circular peripheral line 69 and 70 defining exactly their axial position.

whatever their angular position around the screw 60.

The adjustment process of this device will now be described in relation to FIGS. 21 to 25.

As shown in FIG. 21, the device is in its initial position, the roll-up element being unwound in its first automatic stop position, the stops 61 and 62 being accessible and the mobile element 65 being in any intermediate position. .

In this position, the stop 62 is disengaged in rotation from the screw 60 and then brought, by screwing it on the screw 60, against the switch 67 of the movable element 65 so that the electrical supply to the motor is interrupted (figure 22). As for the stop 61, it is separated as far as possible from the movable element 65.

The roll-up element is then rolled up to its desired second automatic stop position (Figure 23). During this movement, the screw 60 is driven in rotation with the stops 61 and 62 and the movable element 65 moves in the direction of the stop 61 by driving the movable index 68. The movable element 65 and the index 68 s '' immobilize when the rollable element arrives in its second desired automatic stop position.

The rollable element is then unwound to its first automatic stop position (Figure 24).

During this movement, the screw 60 drives the movable element 65 which joins the stop 62 leaving the movable index 68 in its position, and cuts the power supply to the electric motor. In this unrolled position, the stops 61 and 62 are accessible and the installer can bring the stop 61 in front of the index 68 so that its circle 69 coincides with the index 68 (Figure 25).

 The second automatic stopping point is thus adjusted. The device could be equipped with a second movable index 68 detachable in the other direction so as to make the device symmetrical and independent of the direction of rotation of the motor.

In each of the embodiments described, it is possible to reverse the switches and the stops, that is to say to mount the switches on the movable elements and to use the fixed elements as stops for actuating the switches. , as is the case with the last embodiment.

Claims (9)

CLAIMS. 1. Automatic stop device for electric motor ensuring the winding and unwinding of a windable element, comprising two switches (6, 7; 18, 19; 36, 37; 66. 67) corresponding respectively to the position wound and unwound from the windable element and each cooperating respectively with a stop (2, 3; 15, 1 # 6; 32, 33; 61, 62) to cut the power to the motor when the windable element arrives in the position wound, respectively unwound desired, linear drive means (1, 4, 5; 14, 17; 31. 34, 35; 60) of the switches or stops, kinematically linked to the windable element, and adjustment means (4, 5; 24; 48, 49; 63, 64) making it possible to modify the relative position -between each switch and its stop regardless of the movement of the windable element, characterized in that it comprises a tell-tale (8; 20 ; 38; 68) recording the displacement of the movable element, respectively of one of the movable elements, stops or interrupted pteurs, between a first stop position corresponding to the unwound position of the windable element and a second desired stop position corresponding to the wound position of the windable element, and means (10; 22; 40; 69) to postpone the movement recorded by the tell-tale between the other stop and the other switch. 2. Device according to claim 1, characterized in that the indicator is a movable index (8; 20; 38; 68) capable of being driven in one direction by the movable element whose movement it must record. 3. Device according to claim 2, comprising two separate mobile elements, characterized in that the means for postponing the movement of said index consists essentially of a second mobile index (10; 22; 40). 4. Device according to claim 3, wherein the two separate movable elements (32, 33) move along two distinct axes parallel to each other and in opposite directions for the same direction of movement of the windable element. characterized in that the two indexes (38, 40) are driven in one and the same direction by the mobile elements and that their ends move substantially on the same line (57), and coincide when the two mobile elements are in contact with the fixed elements, the indexes being in contact with the mobile elements, so that the transfer of the path traveled pa. one of the mobiles and recorded by one of the indexes can be executed by bringing the other index in coincidence with the first index by means of the mobile element which is associated with it, using the adjustment means (48, 49). 5. Device according to claim 3, wherein the two movable elements (2, 3) move along two distinct axes parallel to each other and in the same direction for the same direction of movement of the windable element. characterized in that it comprises two graduated scales (12, 13) opposite which the indexes (8, 10) move respectively. 6. Device according to Claim # 5, characterized in that the two indexes (8, 10 ') can be driven in one direction by the movable elements (2, 3'). 7. Device according to claim 5, characterized in that the index (10) serving as a transfer means is driven in both directions by the mobile (3) with which it is associated. 8. Device according to claim 3, wherein the two movable elements are constituted by nuts (15. 16) mounted on a common screw constituting said drive means and immobilized in rotation so that they move in the same direction for the same direction of movement of the windable element, characterized in that these nuts are immobilized in rotation by a part (25) made integral in rotation with the nut by a locking means (27) releasable so as to allow the displacement of this nut independently of the drive screw (14) and in that the device comprises two graduated bowls in front of which the indexes (20, 22) respectively move.  9. Device according to claim 2, comprising a single mobile element (65) moving between two axially fixed elements (61, 62) but whose position is adjustable by said adjustment means, characterized in that the means for transferring the displacement of said index (68) are constituted by a mark (69) carried by the adjustable fixed element, mark capable of being brought into coincidence with said index (68).