ITMI20070493A1 - LIMIT SWITCH DEVICE AND A MOVEMENT HANDLING OPERATOR AND METHOD FOR SETTING A LIMIT SWITCH - Google Patents

Description

"Limit switch device for a handling operator, handling operator and method for setting a limit switch point"

The present invention refers to an innovative device

inserting movable elements, such as rolling shutters and the like, into the electrical circuit of an operator for moving elements. The invention also refers to a handling operator and a method for setting a limit switch point in a handling operator,

In the known art of operators for moving elements, such as rolling shutters and the like, limit switch devices are known which are equipped with two sliders coupled with a threaded bar controlled to rotate by the rotation of the operator, so that they slide in agreement on the bar in a manner corresponding to the movement of the actuated element, a detection sensor (generally a microswitch) is associated with each cursor, which signals when the respective cursor has reached its position corresponding to the desired end-of-stroke position for the actuated element. To adjust and vary the two limit switch positions it is necessary to manually adjust the initial position of the two cursors on the threaded rod. This generally takes place by releasing two couplings that normally prevent the free rotation of the cursors on the threaded bar and turning each cursor by hand to bring it into the activation position of its sensor when the element moved by the actuator is in the corresponding desired limit switch position.

In these limit switch devices, the correct setting of the limit switch positions is achieved through several attempts and the expenditure of time and the difficulty of setting are high, the expenditure of time that this adjustment mode implies is particularly evident in the case of operators of the directly mounted type. above the rolling roller of a shutter or similar, where the limit switch device is accessible only when the shutter is completely closed (i.e. completely unwound by the roller). This makes it impossible to directly adjust the limit switch position corresponding to the completely open shutter and forces to proceed with the adjustment by successive approximations starting from the completely closed shutter position.

The general purpose of the present invention is to obviate the aforementioned drawbacks by providing a limit switch device, a handling operator equipped with this device and a method for setting a limit switch point in a handling operator, which allow automatic setting of the point. limit switch, with only one movement of the element operated by the handling operator.

In view of this purpose, according to the invention, it was thought to provide a limit switch device to be inserted in the electrical circuit of an operator handling movable elements, such as rolling shutters and the like, comprising a rotating drive shaft, two sensors detection each corresponding to one of two extreme movement positions to be detected through the alternate rotation of said drive shaft, two cursors each associated with one of the two detection sensors and coupled with a threaded bar driven to rotate by said drive shaft to produce an alternate translation of the cursors towards the respective sensor up to a detection point of the cursor by the sensor, characterized in that it comprises in combination, for the execution of an automatic setting procedure of the limit switch point for one of these sensors, means for deactivating the detection of the corresponding cursor for said sensor and means of stopping the movement of said corresponding cursor towards the sensor at the point of non-detection of it by the sensor.

Still according to the principles of the invention, it was thought to realize an operator group for moving mobile elements such as rolling shutters and the like, comprising a movement gearmotor which is operatively associated with a limit switch group made according to what described above to define two extreme positions stop of the element moved by the gearmotor with an automatic setting of the limit switch point of at least one of these two extreme positions.

According to the principles of the invention, it was also thought to implement a method for setting a limit switch point in an operator for moving a movable element, such as a rolling shutter and the like, and equipped with a limit switch device which is inserted in the electrical circuit of the operator, which is kinematically sensitive to the movement of the mobile element and which includes two detection sensors, each associated with one of two extreme movement positions, and two cursors each associated with one of the two detection sensors and coupled with a threaded bar that is commanded to rotate by the operator to produce an alternate translation of the cursors towards the respective sensor up to a point of detection of the cursor by the sensor, the method comprising the steps of: deactivating the action of the corresponding sensor to the limit switch point to be set; move the movable element towards its position corresponding to that of the limit switch point to be set, so as to move or keep the corresponding cursor towards the point of normal detection of it by the sensor, while preventing, by means of a yielding of the screw which causes the dragging of the cursor caused by the rotation of the threaded bar, that the cursor can continue beyond this point; reactivate the action of the sensor after the moving element has reached the position corresponding to the limit switch point that you want to be set.

To clarify the explanation of the innovative principles of the present invention and its advantages with respect to the known art, a possible exemplary embodiment applying these principles will be described below, with the help of the attached drawings. In the drawings:

-figure 1 represents a partially sectioned schematic view of a handling operator with a limit switch device according to the invention;

figure 2 represents a partially sectioned view of the limit switch device along the line II-II of figure 1;

figure 3 represents a partial perspective view of a guide element present in the limit switch device;

figure 4 represents a partial view of an area of the limit switch device in a normal operating condition,

With reference to the figures, Figure 1 shows a longitudinal section of a movement operator indicated generically with 10 of the type used to move mobile elements such as rolling shutters and the like. This operator 10 comprising a movement gearmotor 11 and a limit switch device 12. operatively associated in a known way so that the movement of the movable element causes the corresponding actuation of the limit switch device which is equipped with two detection sensors 13, 14 each corresponding to one of two extreme handling positions to be detected. The sensors of the limit switch device are inserted in a known way in the electric circuit of the gearmotor so as to allow its normal operation between the two extreme stop positions established by the limit switch device. In the device shown in the figures, the sensors are made with limit switch microswitches.

In particular, the operator 10 shown is of the type intended for mounting directly on a roller or shaft 15 for rolling up a gate or similar rolling elements. For this purpose, the operator includes a wheel 16 with an internal toothed crown to engage in a pinion 17 of the gearmotor and in a gear 18 keyed on the control shaft 19 of the limit switch device. The rolling shaft 15 axially crosses the wheel 16 and is constrained to it to be put into rotation by the gearmotor. Advantageously, the wheel 16 can be opened radially by means of a known system (not shown) to allow the operator to be mounted on the rolling shaft.

A threaded rod or screw 20 is commanded to rotate by the drive shaft 19 to produce a translation of two threaded sliders 21, 22 alternately in one direction or the other on the bar towards or away from the respective sensor 13 or 14 up to a point detection of the cursor by the sensor itself. In the specific case, each slider activates the microswitch by pushing with its periphery against an operating lever of the microswitch. The two sliders have the same thread to translate in a concordant way on the threaded rod.

According to the adopted conventions, the right microswitch 14 supervises the determination of the closing position (completely unwound shutter) while the left microswitch 13 supervises the determination of the opening position (rolled shutter). As the application context varies (shutter height, drum winding diameter, etc.), the position of the limit switches must be set and, in particular, a different distance between the sliders to increase or reduce the stroke between the two positions. limit switch. In prior art devices, the calibration of this distance and the position of the cursors on the threaded bar causes a long and difficult manual setting, as mentioned above. In the device according to the invention, for carrying out an automatic setting procedure of the limit switch point for one of these sensors (the one on the left in figure 1) and therefore of the distance of the two cursors, means 23 are provided for deactivating the detection of the corresponding cursor 21 by the sensor 13 and means 24 for stopping the movement of said cursor 24 at the point (shown in Figure 1) which is normally detected by the sensor.

Advantageously, the means 24 for stopping the movement of the cursor comprise in combination an abutment element or bushing 25 against which the cursor rests when it reaches the said point of normal detection and release means 26 which allow the rotation of the cursor 21 together with the threaded bar 20 when the slider is pushed against the abutment element.

In particular, the device advantageously comprises a guide 27 which is parallel to the threaded bar and which cooperates with the slider to normally prevent its rotation. As can be clearly seen in Figure 2, the guide usually engages in a notch 28 with a plurality of notches on the periphery of the cursors so as to allow axial sliding but not rotation of the latter. Advantageously, the release means comprising a corresponding region 26 of the guide which is made to offer a reduced resistance to the rotation of the cursor in said non-detecting point of the sensor. This resistance is of such a value as to still block the rotation of the cursor when it translates freely, but to allow the rotation of the cursor together with the threaded bar when the cursor is pushed against the stop element by the rotation of the bar. Advantageously, as can be seen in Figure 3 where an end part of the guide 27 is shown in perspective, the reduced resistance zone 26 is made with a plurality of elastically yielding tabs in the direction of rotation of the slider. In this way, the cursor 21, when it reaches the normal detection point of its limit switch sensor 13 and is blocked against further translation by the stop element 25, begins to rotate with the screw, flexing the yielding tabs 26. One rotation opposite of the screw 20 instead moves the cursor away from the abutment element, since the torque transmitted by the cursor is reduced to the point that the tabs 26 are no longer bent and there is the normal translation of the cursor along the guide.

The sliders are also advantageously movable manually, by operating a lever 36 which pivots the guide 27 away from interference with the sliders so as to allow manual rotation of the sliders on the threaded bar.

Advantageously, the aforementioned means for deactivating the detection of the cursor by the sensor (necessary to prevent the movement of the operator from being interrupted during the calibration phase, as will be clarified below) comprise a support 28 which supports the sensor 13 and which it is movable to move the sensor on command between an operating position of normal detection (shown in figure 4) and the non-operative position (shown in figure 1). Advantageously, the displacement from the non-operative position to the operative position is produced by a kinematic mechanism which is sensitive to the displacement of the cursor 21 away from the said point of normal detection. This kinematic mechanism comprises an actuation lever 29 which is moved by the passage of the cursor 21 during its first movement away from the point of normal detection of figure 1. The movement of the lever 29 (to the right in figure 1) disengages a bolt 30 of retaining of the support 28 in the non-operative position against the action of springs 3 1 to peel the support towards the operative position.

Figure 4 shows the displacement effect of the lever 29 which is rotatably pivoted at 32 to the frame of the device and which advantageously comprises a cam track 33 for the movement of the bolt (by means of its pin 24) so as to disengage it from a seat 35 in the support 28, After moving the lever to the right, it no longer interferes with the movement of the slider and the limit switch device remains in its normal operating condition. A manual reset of the lever is possible if you want to proceed with a new calibration of the limit switch point.

From the comparison of Figures 1 and 4, it can be seen that, advantageously, the abutment element 25 moves away from its operating position (in which the cursor 21 rests against it when in the position of normal detection of the limit switch) upon displacement of the sensor holder 28 from its inoperative position to its operational position. This avoids any further interference of the stop elements during the normal operation of the operator.

To obtain this movement, it has been found advantageous to provide a kinematic mechanism with which the abutment element 25 is pushed by a spring 37 towards its non-operative position of Figure 4 and is kept in the operative position of Figure 1, against the action of this spring, by means of a locking tooth 38 which protrudes (integrally or interconnected) from the support 28 so as to interfere with the spring movement of the abutment element when the sensor support is in its lowered non-operative position. In this way, when the lever 29 releases the bolt and the support moves upwards, the tooth 38 comes out of the space between the stop element 25 and the internal wall of the device and the stop element can slide to the left until to the non-operating position of figure 4.

Thanks to the limit switch device according to the invention, the method for setting a limit switch point becomes very easy, essentially, the sensor function corresponding to the limit switch point that you want to be set automatically is deactivated and the movable element is then moved. actuated by the operator towards its position corresponding to that of the limit switch point to be set. This causes the displacement or the maintenance of the corresponding cursor in the point of normal detection of it by its sensor thanks to the fact that it is prevented (through a yielding of the constraint that causes the cursor to be dragged due to the rotation of the threaded bar) that the cursor can continue beyond that point. Finally, after the moving element has reached the position corresponding to the limit switch point that you want to be set, the action of the sensor is reactivated.

For a better understanding, an example of the automatic setting operations of a limit switch point by means of the device according to the invention will now be described. To fix the ideas, it will be assumed that the operator moves a roller shutter. The two corresponding desired extreme limit switch positions for the damper are usually defined with the terms "closed damper" and "open damper". At the beginning of the setting phase of the limit switch point, the device is initially in the condition of figure 1 and the shutter is in the closed position, completely unwound by the roller 15. in other words, at the beginning of the setting phase the mobile element is brought in the opposite limit switch position to the one to be set automatically. To allow the installer to be able to choose whether to move the shutter manually or using the automation, it is necessary that the opening microswitch 30 is not initially activated (otherwise we would have both microswitches activated simultaneously) and is therefore in its lowered position thanks to the mobile support 28.

Conversely, with the shutter closed, the closing microswitch 14 before the automatic learning cycle begins must be activated by manually moving the respective cursor 22 to its sensor activation position, again shown in Figure 1, if necessary.

The fact that the initial condition of the automatic learning cycle coincides with the closed (completely unwound) shutter position is advantageous since in this position the sliders to be adjusted are accessible.

During the first movement of the shutter (towards opening) the closing slider 14 moves to the left while the opening slider 21, unable to move to the left due to the presence of the stop element 25 which acts as an obstacle and to the compliance of the anti-rotation constraint, it rotates integral with the threaded bar and does not translate but remains in its limit switch point.

Once the shutter reaches the desired opening position, the installer reverses the direction of motion of the automation (electrically or manually by acting on the shutter) and therefore also of the threaded rod.

During this second movement of the shutter (towards closing) both move to the right: the cursor 21 performs a stroke which is proportional to the height (total stroke) of the shutter, while the cursor 22 will return to the original position until the corresponding microswitch is reactivated. closing 14. This causes the shutter to stop automatically if the installer uses the automation during the self-learning cycle.

The automatic setting is now complete. The opening slider 21 itself at the beginning of the movement to the right advantageously triggers the device that places the opening microswitch in its final operating position where it can be activated by its slider 21 in steady state operation. The stop bush 25 moves simultaneously to the non-operative position.

At this point it is clear that the predetermined purposes have been achieved since the installer no longer needs to intervene on the limit switch device, except to possibly perform a refinement of the automatically determined positions. The setting of the limit switch point is quick and precise and can be done by means of a single opening and closing cycle of the shutter or similar.

Naturally, the above description of an embodiment applying the innovative principles of the present invention is given by way of example of such innovative principles and must therefore not be taken as a limitation of the patent scope claimed herein. For example, the blocking of the advancement of the cursor can also take place by means of known means for its disengagement from the threaded bar instead of from the anti-rotation guide.

The sensors can also be different from simple microswitches. For example, they can be optical sensors, as easily imagined by the technician. The deactivation of sensor detection can also take place electrically, by interrupting the signal emitted by the sensor or its effect on the operator, instead of moving the sensor. The transmission of the motion to the threaded bar can take place with kinematic connections different from those shown, as can be easily imagined by the technician.

Claims (20)

CLAIMS 1. Limit switch device (12) to be inserted in the electrical circuit of an operator (10) for moving moving elements, such as rolling shutters and the like, comprising a rotating drive shaft (19), two detection sensors (13, 14} each corresponding to one of two extreme movement positions to be detected through the alternate rotation of said drive shaft, two cursors (21, 22) each associated with one of the two detection sensors and coupled with a threaded bar (20) commanded to rotate from said drive shaft to produce an alternate translation of the cursors (21, 22) towards the respective sensor up to a point of detection of the cursor by the sensor, characterized in that it comprises in combination, for the execution of a procedure of automatic setting of the limit switch point for one of these sensors, means (23) for deactivating the detection of the corresponding cursor for said sensor and means (24) for stopping the movement of this corresponding cursor towards the sensor at the point of normal detection thereof by the sensor. 2. Limit switch device according to claim 1, characterized in that the means for stopping the movement of the slider comprising in combination an abutment element (25) against which the slider rests when it reaches the said point of normal detection and means (26 ) which allow the rotation of the slider together with the threaded bar when the slider is pushed against the stop element. 3. Limit switch device according to claim 2, characterized in that it comprises a guide (27) parallel to the threaded bar and which cooperates with the cursor to normally prevent its rotation, the release means comprising a corresponding region (26) of the guide which is made to offer reduced resistance to the rotation of the slider at said normal detection point in such a degree as to allow rotation of the slider together with the threaded bar when the slider is pushed against the abutment element. Limit switch device according to claim 3, characterized in that said region of the guide with reduced resistance is made with elastically yielding tabs (26) in the direction of rotation of the slider. Limit switch device according to claim 1, characterized in that the means for deactivating the detection of the cursor by the sensor comprise a support (28) for supporting the sensor which is movable to move the sensor on command between an operative detection position and an inoperative position. 6. Limit switch device according to claim 5, characterized in that the displacement from the inoperative position to the operative position is produced by a kinematic mechanism (29, 30, 31) sensitive to the displacement of the cursor away from the said non-operating point. Limit switch device according to claim 6, characterized in that the kinematic mechanism comprises an operating lever (29) which is moved by the passage of the cursor during the movement away from said normal detection point. Limit switch device according to claim 7, characterized in that the movement of the operating lever (29) disengages a latch (30) for holding the sensor support (28) in the inoperative position against the action of springs (31) pushing the support towards the operating position. Limit switch device according to claim 8, characterized in that the actuation lever (29) is rotatably pivoted and comprises a cam track (33) for the movement of the bolt (30) during its rotation. 10. Limit switch device according to claims 2 and 5, characterized by the fact that the stop element (25) moves away from its operating position to the displacement of the sensor support (28) from its inoperative position to its operating position. 11. Limit switch device according to claim 10, characterized in that the stop element (25) is pushed by spring towards its non-operative position and is maintained in the operative position by means of a locking tooth (38) protruding from the said sensor support (28) to interfere with the spring movement of the abutment element when the sensor support is in its non-operative position. Limit switch device according to claim 1, characterized in that it comprises a guide (27) parallel to the threaded bar and which cooperates with the cursors (21, 22) to normally prevent their free rotation, said guide being supported to be manually movable between an operative position of engagement in the sliders and an inoperative position of free rotation of the sliders. 13. Limit switch device according to claim 1, characterized in that the sensors are limit switch microswitches. 14. Operator for moving moving elements such as rolling shutters and the like, comprising a moving gearmotor (11) which is operatively associated with a limit switch device (12) made according to any one of the preceding claims to define two extreme stopping positions of the element moved by the gearmotor with an automatic setting of the limit switch point of at least one of these two extreme positions. 15. Method for setting a limit switch point in a moving operator of a mobile element, such as a rolling shutter and the like, and equipped with a limit switch device which is inserted in the operator's electrical circuit, which is kinematically sensitive to the movement of the mobile element and which comprises two detection sensors, each associated with one of two extreme movement positions, and two cursors each associated with one of the two detection sensors and coupled with a threaded bar which is commanded to rotate by the operator to produce an alternate translation of the cursors towards the respective sensor up to a point of detection of the cursor by the sensor, the method comprising the steps of: deactivating the action of the sensor corresponding to the limit switch point to be set; move the movable element towards its position corresponding to that of the limit switch point to be set, so as to move or keep the corresponding cursor towards the point of normal detection of it by the sensor, while preventing, by means of a failure of the constraint that causes the cursor to be dragged caused by the rotation of the threaded bar, that the cursor can continue beyond this point; reactivate the action of the sensor after the moving element has reached the position corresponding to the limit switch point that you want to be set, 16. Method according to claim 15, in which before moving the movable element towards its position corresponding to that of the limit switch point that you want to be set, the movable element is positioned in a position corresponding to an opposite limit switch point. 17. Method according to claim 15, in which, for setting a second limit switch point opposite to the first one, the movable element is positioned in the position corresponding to said second limit switch point and the cursor corresponding to the sensor to be activated in this position is moved manually until this sensor is activated. 18. Method according to claim 15, in which the mobile element wraps around an axis rotated by the handling operator and that the limit switch point to be set corresponds to the wrapped mobile element. Method according to claim 15, in which to deactivate the sensor, the sensor is moved from its operative position to an inoperative position in which it cannot detect the corresponding cursor. 20. Method according to claim 19, in which to reactivate the sensor, the sensor is moved from its non-operative position to its operative position thanks to the movement of the corresponding cursor which moves away from said normal detection point.