EP0568492B1 - Automatic braking device for motorised electronic operation of a door, shutter, blind or similar - Google Patents

Abstract

A compact automatic stop device for two mechanisms for counting revolutions which consist of coaxial counting wheels (10, 10') each associated with a notched cam (14, 14') interacts with a cutoff finger (24, 24') securely fastened to a common cutoff lever (20, 20'), so that when the notches (19) are aligned, the cutoff lever actuates a switch (26, 26'). A set-to-zero lever (29, 29') makes it possible to reset the counting wheels to zero by acting via hammers (33') on core cams (18'). The counting wheels, the cutoff levers and the set-to-zero levers of each counting mechanism are pivoted in a common cradle (5, 5') articulated with respect to a fixed casing (1) having profiled parts (36, 37, 36', 37') which are intended to interact with the cutoff levers and the set-to-zero levers during the displacement of the cradles.

Description

The present invention relates to an automatic stop device for the electric motorized drive of a door, shutter, blind or the like, comprising two revolution counting mechanisms, consisting of coaxial wheels driven at different speeds and each associated with a cam. with a notch cooperating with a cutting finger integral with a common cutting lever biased by a spring holding the cutting fingers in abutment against the notched wheels so that when the notches are aligned, the cutting fingers penetrate into the notches and a switch is actuated by the cut-off lever, the device further comprising two mechanisms for zeroing the counting mechanisms essentially consisting of means for disengaging the counting wheels and a zeroing lever provided with hammers acting on heart cams associated respectively with each of the wheels of the counting mechanism.

Such a device is known from patent FR 2 455 695 with the difference, however, that this prior device only comprises a single counting mechanism. In this device, the differential movement of the counting wheels is obtained by a kinematic connection produced by means of a return element with intermittent meshing pivoted on an axis parallel to the counting wheels. This type of meshing makes it possible to count a large number of turns with good precision, but has drawbacks when it comes to making a device ensuring two automatic stopping points as this is generally necessary in the case of a blind or roller shutter. Indeed, to drive two mechanisms counting, it is necessary to have two independent references which must be pivoted either on two different axes themselves different from the axis supporting the entry of the movement on the first wheel, or on the same axis but the references being then arranged in the extension of one another. In addition, an intermittent meshing requires accompanying arrangements such as that of the presence of a holding spring in position during the non-meshing period. All this is a source of significant bulk, complications and therefore additional cost. In addition, in the prior device, the means for disengaging and zeroing the counting wheels are relatively complicated and the counting wheels are mounted on a cradle pivoting on the frame while the cut-off lever is mounted directly on the frame. . This lengthens the chain of tolerances and requires compliance with great precision on the elementary components of the device.

From US Pat. No. 4,171,473, there is also known a counting mechanism comprising three counting wheels arranged coaxially and in which each counting wheel meshes with a separate pinion, the pinions being arranged on the same axis with which they are integral in rotation. The differential movement of the counting wheels is obtained thanks to a different ratio between each pair of wheel and pinion. Each wheel has sliding zones and notches cooperating with rollers having the function of cutting levers. This device is complex and requires a pinion axis by counting mechanism, a pinion by counting wheel and a kinematic connection between each counting axis and the input axis of the movement. In addition, returning to the start of counting is not easy, nor very fast because it is necessary, after having brought the door, roller shutter or the like in the desired stop position, to act axially on a thumb wheel to disengage the pinion axis from the input axis, then drive it manually in rotation until the counting wheels of the counting mechanism assume the position allowing all the rollers of the cutting mechanism to simultaneously penetrate into the notches of the counting wheels. If the counting wheels are in any position, the operation may take a long time.

The object of the invention is to provide an automatic stop device with two stop points which is simpler and less bulky than the prior devices.

The automatic stop device according to the invention is characterized in that the counting wheels, the cut-off levers and the zeroing levers specific to each of the counting mechanisms are pivoted in a common articulated cradle, relative to a fixed frame carrying the input pinion and the switches, about an axis parallel to the axis of the counting wheels, so that each of these cradles can pivot from a first position, in which the counting wheels are in engagement with the pinion, towards a second position, in which the counting wheels are spaced from said pinion, and in that the fixed frame has profiled parts intended to cooperate with the cut-off levers and the zeroing levers during displacement of the cradles, so as to ensure zeroing of the heart cams and closing of the corresponding switch when the cradles are brought into their second position, springs being pr seen to keep the counting wheels meshed, the cutting fingers pressing on the notched cams and the zeroing levers pressing on the corresponding profiled parts of the fixed frame.

Each cradle, with its counting wheels, its cut-off lever and its zero-setting lever, constitutes a relatively simple unit whose precision is easy to ensure. The transmission mechanism of the disengaging and zeroing control of the prior art is eliminated in favor of simple profiled contours of the frame playing the role of fixed cams controlling the movement of the reset lever and the cut-off lever during pivoting of the cradle.

The counting wheels are preferably driven by a common input gear with two different teeth. In each counting mechanism, some of the wheels are engaged with one of the teeth and the others with the other teeth.

According to a preferred embodiment of the invention, the springs are reduced to two for the whole of the device, one of these springs connecting together the cut-off levers of the two counting mechanisms and simultaneously ensuring the clutched engagement of the wheels and the other spring connecting the zeroing levers of the two counting mechanisms to each other. In comparison, a device according to French patent 2 455 695 comprises three springs by counting mechanism, without counting the spring for holding in position the return element with intermittent meshing.

The counting mechanisms can be arranged on either side of the input axis, preferably symmetrically, the axial size of a device with two breakpoints is the same as that of a single breakpoint device.

The accompanying drawing shows, by way of example, an embodiment of the device according to the invention.

Figure 1 is an axial view of the device in the engaged position of the two counting mechanisms.

Figure 2 is a sectional view along II-II of Figure 1, the part to the left of the axis of symmetry being shown without the zeroing lever, while the part to the right of the axis is shown without the cut-off lever.

Figure 3 is a view similar to that of Figure 1 in which one of the cradles is shown in the disengaged position and zeroed.

The device shown comprises a frame 1 in which is pivoted a shaft 2 carrying a long pinion having, along its length, two different teeth 3 and 4. The shaft 2 is intended to be driven by the drive motor of the door, blind, roller shutter or the like, more precisely by the output of the reduction gear associated with this motor. On the frame 1 are also mounted, symmetrically to the axis 2, two identical cradles 5 and 5 'pivotally mounted on the frame 1 around a common axis 6 located in the plane of symmetry of the device and they are provided with an arm 5a, respectively 5'a, by which they can be tilted manually by means of pushers not shown.

In the cradle 5 are coaxially mounted four counting wheels 7, 8, 9, 10 free to rotate on a common axis. The wheels 7 and 8 have a different number of teeth and the same is true of the wheels 9 and 10. Each of the counting wheels is flanked on one side by a notched cam consisting of a smooth wheel coaxial with the wheel counting and whose circumference is interrupted by a notch 19 (Figure 1), and on the other side of a core cam forming a block with the counting wheel. The counting wheels 7, 8, 9, 10 are thus respectively associated with a notched cam 11, 12, 13, 14 and with a heart cam 15, 16, 17, 18.

In the cradle 5 is further pivoted a cut-off lever 20 around an axis 27 parallel to the axis 2. This cut-off lever 20 is provided with four fingers 21, 22, 23, 24 rigidly connected to the cut-off lever and cooperating respectively with the notched cams 11, 12, 13, 14. The cut-off lever 20 is further provided at one of its ends with a bent arm 25 rigidly connected to the cut-off lever and intended to actuate a first switch 26 fixed on an extension of the frame 1.

In the cradle 5 is further pivoted about an axis 28 parallel to the axis 2, a zeroing lever 29 provided with four arms constituting hammers intended to actuate each of the core cams 15 to 18 respectively. Figure 2, the zeroing lever and its hammers have not been shown, so as to clearly see the cut lever. In Figure 1, only one of the hammers 33 is visible.

The second counting mechanism mounted in the cradle 5 ′ is produced identically to the first counting mechanism and comprises the same elements which have been designated by the same references as those of the first counting mechanism accompanied by the sign 'so as to avoid repetition of the description. The zeroing lever 29 ′ of this second counting mechanism is visible in plan on the right side of FIG. 2. There are the four zeroing hammers 30 ′, 31 ′, 32 ′, 33 ′. The cut-off lever 20 ′ of the second mechanism has not been shown in FIG. 2. It will be noted that the symmetry of the two counting mechanisms is not complete, the position of the notched cams and of the core cams being reversed with respect to the position of these elements in the first counting mechanism, the parts consisting of a counting wheel, a notched cam and a core cam being the same for the two counting mechanisms. The cutting fingers and the zeroing hammers are therefore offset relative to the same elements of the first counting mechanism.

The bent arm 25 'of the cut-off lever of the second counting mechanism cooperates with a second switch 26' fixed like the switch 26.

The cut-off levers 20 and 20 'are interconnected by a first tension spring 34 which simultaneously has the effect of keeping the cut-off fingers in contact with the notched cams and of keeping the counting wheels of the two mechanisms engaged with the teeth 3 and 4 of the input pinion. The zeroing levers 29 and 29 ′ of the two mechanisms are also connected by a second tension spring 35 which provides the force necessary for actuating the heart cams.

The frame 1 has, on each side, profiled parts 36 and 37, respectively 36 'and 37' playing the role of cams for controlling the movement of the levers zero setting 29 and 29 'and cut-off levers 20 and 20'.

In the left-hand part of FIG. 1, we can clearly see the shape of the profiled part 36 in the form of a lateral projection having at its end a ramp on which a spout 38 is supported which constitutes the end of the zero-setting lever 29.

While the zeroing levers 29 and 29 'are supported on the profiled parts 36 and 36' when the counting wheels are engaged with the input pinion, the profiled parts 37 and 37 'do not come into contact that momentarily with the bent arms 25 and 25 ′ of the cut-off levers during zeroing, as will be described later in relation to FIG. 3.

In FIGS. 1 and 2, the cutting fingers 21 to 24 are shown engaged in the notches of the notched cams 11 to 14, which means that the first counting mechanism is in a stopped position, the bent arm 25 of the cut-off lever acting on the switch 26 under the effect of the spring 34. On the other hand, the cut-off fingers of the second counting mechanism are not engaged in the notches of the notched cams 11 'to 14'. The second mechanism is therefore in an intermediate position in which the bent arm 25 'is kept apart from the switch 26'.

The device is used with a motor with two windings allowing the motor to rotate in two directions of rotation. Switch 26 is connected in series with one of the motor windings and a switch for controlling a first direction of rotation, while the other switch 26 'is connected in series with the second motor winding and a switch for controlling the second direction of rotation.

A vertical pressure on the arm 5'a of the cradle 5 has the effect of tilting the latter around its axis 6 as shown in FIG. 3. The counting wheels are disengaged from the teeth 3 and 4 of the input pinion and , during this tilting, the spout 38 'of the zeroing lever 29' leaves the profiled part 36 'allowing the zeroing lever 29' to pivot in the direction of the heart cams. Under the effect of the spring 35, the zeroing hammers 30 'to 33' act on each of the heart cams 15 'to 18' and align the notches of the notched cams 11 'to 14'. The bent arm 25 ′ of the cutting lever abuts against the profiled part 37 ′ of the frame and it is moved away from the switch 26 ′. When the pressure on the actuating arm 5 ′ a of the cradle 5 ′ is then released, it returns to its initial position, the zeroing and cut-off levers then occupying the position shown in the left part of the FIG. 1, that is to say cutting fingers in the notches of the notched cams and switch 26 actuated by the bent arm 25.

The setting of the stopping points of the device is carried out as follows:

The direction control switch 1 being activated, that is to say closed, the cradle 5 of the first counting mechanism is brought into its declutching and zeroing position corresponding to the position 5 'shown in the figure 3. The first winding of the motor is supplied and the controlled component (door, blind or roller shutter) is driven. When the first desired automatic stop point is reached, the cradle 5 is released and comes to occupy the position shown in FIG. 1. The switch 26 is actuated and the motor is no longer supplied.

We proceed in a similar way to set the second automatic stop point by actuating the direction control switch 2 and moving the cradle 5 'as shown in FIG. 3. As soon as the second desired stop point is reached, the cradle 5 ′ is released, the levers of which occupy the same position as that of the cradle 5 in FIG. 1.

During the setting of the second stop point, the counting wheels of the first counting mechanism were rotated and the notches of the notched wheels no longer coincide. The levers of the first mechanism occupy the position shown in Figure 3.

Operation during the period of use will be described from the position shown in FIG. 1. In this position, the adjusted device is in its first stop position. The switch 26 is open and an action on the first direction control switch has no effect. An action on the second direction of rotation control switch on the other hand has the effect of powering the motor and driving the controlled member until the notches of the notched wheels of the second counting mechanism arrive in alignment allowing the cut-off lever 20 'to switch and actuate the switch 26' causing the engine to stop in its second stop position.

Meanwhile, the counting wheels of the first counting device have been driven and their notches are no longer aligned, so that at least one of the cutting fingers is in contact with the circular part of the corresponding notched wheel and the corresponding switch is not actuated, as shown in FIG. 3.

The device described is of course subject to variations. In particular, the number of counting wheels for each counting mechanism could be different from four, but practically a minimum of three counting wheels must be provided, for example two wheels meshing with teeth 3 and one wheel meshing with teeth 4. Each counting mechanism can for example comprise two times three wheels cooperating respectively with the teeth 3 and 4 or three wheels meshing with one of the teeth and two wheels with the other teeth of the input pinion. Instead of two springs common to the two mechanisms, provision could be made for springs specific to each mechanism.

The device could include two parallel input gears, one for each counting mechanism.

Claims (3)

1. Automatic stop device for the electric drive of a door, shutter, blind or the like, comprising two revolution-counting mechanisms, consisting of coaxial wheels (7 through 10, 7' through 10') driven by at least one gear at different speeds and each associated with a notched cam (11 through 14, 11' through 14') interacting with a cutoff finger (21 through 25, 21' through 24') securely fastened to a common cutoff lever (20, 20') stressed by a spring holding the fingers bearing against the notched cams so that when the notches (19) are aligned, the cutoff fingers penetrate the notches and a switch (26, 26') is actuated by the cutoff lever, the device further comprising two mechanisms (29, 29') for setting the counting mechanisms to zero and consisting essentially of means for disengaging the counting wheels and of a set-to-zero lever (29, 29') fitted with hammers (33, 30' through 33') acting on core cams (15 through 18, 15' through 18') respectively associated with each of the wheels of the counting mechanism, characterized in that the counting wheels (7 through 14,7' through 14'), the cutoff levers (20, 20') and the set-to-zero levers (29, 29') belonging to each of the counting mechanisms are pivoted in a common cradle (5, 5') articulated, with respect to a fixed casing (1) carrying the input gear and the switches, about a spindle (6) parallel to the axis of the counting wheels, so that each of these cradles may pivot from a first position, in which the counting wheels are engaged with the gear (3, 4), to a second position in which the counting wheels are moved away from said gear, and the fixed casing (1) has profiled parts (36, 37, 36', 37') intended to interact with the cutoff levers and the set-to-zero levers during the displacement of the cradles, so as to set the core cams to zero and to close the corresponding switch when the cradles are brought into their second position, springs (34, 35) being provided to keep the counting wheels engaged, the cutoff fingers bearing on the notched cams, and the set-to-zero levers bearing on the corresponding profiled parts of the fixed casing.
2. Automatic stop device as claimed in claim 1, characterized in that it comprises a long input gear with two sets of teeth (3, 4) common to the two counting mechanisms arranged on either side of the axis of this gear, each counting mechanism comprising at least three counting wheels, at least one of which engages with one of the sets of teeth of the input gear, and the others with the other set of teeth of the input gear.
3. Automatic stop device as claimed in claim 2, characterized in that said springs consist of a first tension spring (34) connecting the cutoff levers of the two cradles and of a second tension spring (35) connecting the set-to-zero levers of the two cradles, the counting wheels therefore being kept engaged with the input gear by the first spring.

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