FR2821878A1 - Process, for controlling operation of sliding door of refrigerating room, involves electronic drive unit varying torque of motor drive according to state of position sensor integrated into motorized unit - Google Patents

Abstract

Method involves electronic drive unit (11) that varies torque of motor drive (1), according to state of position sensor integrated into motorized unit. Torque varies between first value, corresponding to maximum force applied to door (9) during first opening phase, and second value, corresponding to minimum force ensuring constant movement of door along rectilinear part of rail (3), during opening and closing. Control and signaling systems are activated to signal and modify door operation during an opening and closing cycle. When door is opened, drive motor operates until the open position of the door is detected, then the motor is stopped and triggers a first time delay. After time delay has elapsed, motor is started in the closing direction until closed door is detected, and second time delay is triggered for inhibiting opto-electronic security sensors (15,16). An Independent claim is also included for an electronic drive system for the door.

Description

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 The invention which relates to the sliding doors of refrigerating chambers relates more precisely to a method for controlling the operation of these doors, as well as to the power unit enabling the implementation of this method.

 These sliding doors are usually equipped at their upper part with guide rollers thanks to which they are suspended from a sliding rail, and they move between a closed position to guarantee perfect sealing, and an open position. So that when closing, sealing is ensured, it is known to equip the sliding rail with notches oriented downwards and judiciously arranged, so that when the rollers descend into these notches, the door undergoes a identical movement of descent which applies the door seals to the floor as well as to the frame of the frame.

 There are various automatic means for moving such a door. Apart from pneumatic devices or electric jacks, a currently widespread solution consists in connecting the door to a movement transmission member consisting for example of an endless chain or belt returning on two pinions, each placed at a end of the door travel zone. A clutch linked to a motorization ensures the transmission of movement between a geared motor group and a drive pinion. Of course it is necessary, at the time of opening the door, that the torque exerted by the clutch is sufficient, not only to detach the door from the seals against which it is applied and to overcome the friction resulting therefrom, but also to release the rollers from their notches in order to reassemble the door on the horizontal running part of the rail. As these insulated doors are often heavy, the effort required is significant, but only during the very first phase of opening the door. Also we regulate the pressure on the clutch so that the door can come out of the notches; but this non-adjustable setting turns out to be too

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powerful when the door is removed from its notches and moves on the rail, which has a drawback when the direction of translation is reversed as this causes unacceptable jolts;
Admittedly, one could obtain a variation of torque by using a DC motor, but this solution is much more expensive and requires taking special safety precautions.

 To overcome this drawback, we thought of using two geared motor groups, one for driving the door flat on the rail and the other to serve as a backup only to ensure the exit of the notches. To this end, this second booster or start-up group has a power and develops a torque greater than that of the first, and advantageously its output shaft carries a cam which cooperates with a roller carried by the door, a cam whose active part exerts briefly and in less than a turn, a large force on the roller to clear the door of the notches.

 Another solution consists in using the geared motor group necessary for moving the door, as described in FR 2681899 in the name of the Applicant, but by associating it with a torque variator device which modulates the pressure exerted by the clutch at the time the start of the opening movement, in relation to the continuous movement of the door. Thus the opening is done in two phases, the exit of the door and the translation of the latter until the maximum opening.

 Rather than the implementation of such a mechanical torque variator system, the invention proposes another solution now based on an electronic control unit, by means of which the engine torque available at the output of the power unit can be varied, during the various opening and closing phases of the door, said control being linked to a position detection system integrated into the motorization group, control and signaling devices being furthermore provided,

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 allowing to remedy the operational irregularities during the cycle.

 The main object of the invention is therefore a method for controlling the operation of a sliding door, in particular of a refrigerating chamber, which moves on a rail by means of a belt driven by the engine of a power unit, method according to which an electronic control unit varies the torque of the drive motor, according to the position of the door detected by a position detection system integrated in the motorization group, said torque varying between a value corresponding to a maximum force applied to the door during the first phase of opening thereof, and another value corresponding to a minimum effort ensuring the constant translation of the door on the straight part of the rail, during its opening and closing, of the control devices and signaling devices are activated to signal and remedy operational problems during the cycle.

 Another main object of the invention relates to a device for implementing the method, according to which the electronic control unit of the motorization group is connected to a wall control box, which being connected at least to a flashing light and optoelectronic safety cells.

Other particular characteristics and advantages of the invention will emerge from the description which follows of an exemplary embodiment in which reference is made to the appended drawings which represent:
Figure 1, a schematic elevational view of a sliding door and the drive belt.

 Figure 2, a schematic view of the installation equipped with the electronic control unit.

 Figure 3 and 4, curves showing the variations of the torques applied to the motor with respect to the forces required, respectively for the opening and closing of the door.

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There is shown schematically in FIG. 1 a sliding door 9 suspended by rollers 2 from a guide rail 3.

 In the position shown, the door 9 is closed and the support rollers are immobilized in two notches or ramps 4 provided on the rail. The door is driven from this position to an open position represented in dotted lines by an endless belt 5 to the lower strand from which it is attached by a connecting member 6.

 The belt returns to a tension pulley 7 and to a drive pulley 8 forming part of the power unit designated as a whole by the reference 1.

 We see more precisely in Figure 2 a sliding door 9 and its arrangements for its electronic control. The drive unit 1 or motor is arranged at the end of the guide rail 3 on the opening side.

Transmission is ensured by the driving pulley 8 wedged on the output shaft of the reducer driving the belt 5.

The belt is tensioned by a tensioner 10 installed on the rail on the closing side.

 The electronic control unit is advantageously integrated in a box 11 made integral with the motor 1. The box is closed at the rear by a plate equipped with the various electrical connections, namely a box 12 for connection to the mains, a control box wall 13 connected to a flashing light 14, an optoelectronic safety cell 15 in vertical barrier on the edge of the door and another safety cell 16 in horizontal barrier. The front of the housing is advantageously closed by a plate fitted with the control interface. This will be integral with the electronic control unit and will constitute an interchangeable module to facilitate maintenance operations.

 The security cells (15,16) are positive security and operational when the door is closed. The supply voltage of the horizontal cells

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 16 is available from the control unit 11 via the multi-wire output cable and that of the vertical cell from the electronic unit of the power unit.

 The assembly formed by the motor of the motorization group and the control unit can operate independently.

 The opening and closing control of the sliding door can be carried out in two modes which can be selected from the electronic unit 11, an automatic mode where the complete opening and closing cycle is carried out by a single action of the "on" button on the control unit 13, ie a manual controlled mode in which the opening and closing are each effected by an impulse on the "on" button.

Tl. Le système de détection de position est intégré au groupe de motorisation. Les réglages de position doivent tenir compte de l'inertie des masses en mouvement, des résistances passives variables avec la température de fonctionnement, et du rebond éventuel sur les butées de porte. Le réglage de la course totale, simple et accessible à tous utilisateurs, s'effectue manuellement ou automatiquement lors de la mise en service du système.

In the case of operation in automatic mode, the door 9 being closed, an impulse on the "start" button starts the cycle. The motor is supplied in the opening direction until the door opening position is detected, which stops the motor and triggers a time delay.

Tl. The position detection system is integrated into the engine group. The position adjustments must take into account the inertia of the moving masses, the passive resistances that vary with the operating temperature, and any rebound on the door stops. The adjustment of the total stroke, simple and accessible to all users, is carried out manually or automatically when the system is put into service.

A torque Cl (see Figure 3) corresponding to a maximum opening force F, is applied to the door during the first phase where it must come out of the notches or ramps 4, and the torque must be applied over a distance dl at least equal to that of the ramp, for example 0.15 m.

Then a torque C2 is applied, corresponding to a minimum minimum effort F2, for the constant translation of the door on the rectilinear part of the rail, the movement taking place in the diagram of FIG. 3, in the direction

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des abscisses. Les valeurs de Ci et C2 sont ajustables pour assurer un fonctionnement"en douceur"selon le poids de la porte considérée. A partir des données expérimentales, ces valeurs pourront varier par exemple dans les limites suivantes.

abscissa. The values of Ci and C2 are adjustable to ensure "smooth" operation depending on the weight of the door considered. From the experimental data, these values may vary for example within the following limits.

CI from 2 to 5 m daN
C2 from 0.7 to 1 m daN
After the delay Tl has elapsed, the motor is supplied in the closing direction until the closing position is detected, which triggers a delay T3 for inhibiting the vertical and horizontal safety optoelectronic cells (15,16).

 On closing (see Figure 4) a starting torque C'2 corresponding to a starting force F'2 is applied, slightly greater than the torque C2 to overcome the inertia of the door and initiate its translational movement which takes place then with the same torque C2 as that provided for the opening. In the event of reversal of the direction of travel, for example a door return at the opening, the torque 2 is also applied except for a distance d2 close to the closing or the torque Ci must be applied. The distance d2 is not less than 0.30 m.

 To limit the jolts linked to the starting torque of the asynchronous motors, provision is made to apply a progressive starting force to them.

 During the movement of the door, the flashing light 14 for signaling is activated. When a delay T4 warning signaling by the flashing light is selected on opening and closing, or only on closing, the motor is supplied after this time has elapsed.

 In the case of operation in controlled mode, pressing the "start" button opens the door. It remains open until a new pulse closes it. Each pulse switches the direction of rotation of the motor except in the opening direction. The action of timers T3 and T4 remains identical to automatic mode.

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The electronic control unit takes into account the various operating hazards that may arise during the cycle. This is the case when there is an untimely blocking of the door for example by an object, a pallet, etc. It is expected that each time the engine is started, in the opening or closing direction, a time delay T2 is triggered, on the order of 10 seconds.

If the door, due to the obstacle encountered, has not reached its open or closed position after this time T2, the motor supply is cut and a warning light relating to a fault starts to flash.

After solving the problem, you can deactivate the indicator light using an appropriate button and a new action on the start button restarts the operation. This appropriate button called "stop punch" allows the movement of the door to be stopped in all circumstances, the start button allowing restarting.

 Another operational hazard can result from the cutting of the beam of the optoelectronic cells (15,16).

 During the closing of the door, if one of the beams is simply cut, the door is sent back to the opening to the torque C2'S If this cut occurs in the zone d2 close to the closing (figure 4), the door is returned to the opening at torque Cl. In automatic operation, when the door is open, cutting the beam of the cells has the effect of restarting the time delay Ti. If the beam remains permanently cut for a time of less than one minute, the time delay Tl is not restarted until after deactivation of the optoelectronic cell. For a prolonged blackout beyond one minute, the system goes into fault, signaled by the flashing of the indicator. In controlled mode, the door closes after pressing the "start" button, if the beam is not obscured.

 Regarding possible actions on the "start" button, during the door opening phase, a new impulse has no effect whatever the mode, but during the closing phase it causes the

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réouverture de la porte dans les deux modes. Durant la temporisation Tl une nouvelle impulsion sur le bouton aura pour effet de réarmer cette temporisation.

reopening the door in both modes. During the Tl delay, pressing the button again will reset this delay.

 Finally, another hazard results from a cut in the sector.

Following this, after the power has been restored, the motor must be stopped, indicated by the flashing of the fault indicator, and whatever the position of the door which is manually returned to the closed position, it must be operated the button to reset the system.

Claims (14)

 1.-Method for controlling the operation of a sliding door, in particular of a refrigerating chamber, which moves on a rail by means of a belt driven by the motor of a motorization group characterized in that an electronic piloting unit varies the torque (Ci, C2, C'2) of the drive motor (1), depending on the position of door 9 detected by a position detection system integrated in the motorization group, in that said torque

 varies between a value (Cl) corresponding to a maximum effort (Fi) applied to the door during the first phase of opening it, and a value (C2) to corresponding to a minimum effort (F2) ensuring constant translation of the door on the rectilinear part of the rail, when it is opened and closed, and in that control and signaling devices are activated to signal and remedy the vagaries of operation during the cycle.  2. -Process according to claim 1 characterized in that the control is carried out in automatic mode where the complete opening and closing cycle is carried out by a single action on a button "start" of the electronic control unit .  3. -Procédé according to claims 1 and 2 characterized in that the motor is supplied in the opening direction until detection of the door open position, which stops the motor and triggers a time delay Ti.  4. -A method according to claims 1 and 3 characterized in that, after expiry of the time delay (T1), the motor is supplied in the closing direction until detection of this closing position which triggers a time delay (T3) of inhibition of optoelectronic safety cells (15,16).  5. -A method according to claim 1 characterized in that when the door is closed, a starting torque (C'2) corresponding to a starting force (F'2) is applied to the motor, the torque (C'2 ) being slightly greater than the torque <Desc / Clms Page number 10>  (C2) to overcome the inertia of the door and initiate its translational movement with the couple (C2).

 6. -A method according to claim 1 characterized in that the motor is supplied after the expiration of a time delay (T4) warning signaling of the movement of the door materialized by a flashing light (14).  7. -A method according to claim 1 characterized in that a time delay (T2) is triggered each time the engine is started in the opening or closing direction, and in that the motor power is cut if the door has not reached its open or closed position at the end of time (T2), in the event of an operational hazard by blocking the door.  8. -A method according to claims 1 and 4 characterized in that in the event of an operational hazard linked to the cutting of the beam of an optoelectronic safety cell, the door is returned to the opening with the torque (C2) or ( CI) according to the position of the door.  (Tl).

 9. -A method according to claims 3 and 8 characterized in that in automatic operation, when the door is open, the cut of the beam restarts the time delay  10. -Process according to claim 1 characterized in that in the event of an operational hazard linked to a power cut signaled by the flashing of a "fault" indicator, the door is manually returned to the closed position before resetting the system .  11.-Method according to claim 1 characterized in that the control is carried out in manual mode where the opening and closing cycle is ensured each time by an impulse on the button "start" of the electronic control unit .  12. -Device for implementing the method according to any one of claims 1 to 11 characterized in that the electronic control units of the power unit (1,8) is connected to a control unit <Desc / Clms Page number 11>  wall (13), which being connected at least to a flashing light (14) and optoelectronic safety cells (15, 16).  13. -Device according to claim 12 characterized in that the electronic control unit is integrated in a housing (11) integral with the motor (1), closed by a plate equipped with a control interface forming an interchangeable module.  14. -Device according to claim 12 characterized in that the optoelectronic safety cells consist of a cell (15) in vertical barrier mounted on the edge of the door (9) and a cell (16) in horizontal barrier .