EP0091360B1 - Mechanical remote control for electric motors with explosion protection - Google Patents

Abstract

1. Mechanical remote control for anti-deflagrating motors of the type in which a motor (2) comprises a resilient returning on-off control crankshaft (1) connected by a movement transmission means (31) to a mobile means (21) to which can be manually imparted a reciprocating motion by acting on an handling button (22), characterized in that said mobile means has the shape of a slide (21) having a groove (30) and a thinned portion (21a) with a shoulder (29), said slide (21) being placed between a first (10) and a second (11) pivoting plates mounted on two rods which are parallel to each other and perpendicular to the sliding direction of the slide (21), said pivoting plates (10, 11), normally urged for tending to make them to pivot the one towards the other, able to be activated by an olive (23) mounted so that it can move in a longitudinal direction which is parallel to the direction of movement of the slide (21) and also placed between said two pivoting plates (10, 11), the first pivoting plate (10) being further able to be submitted through a bearing (17) to action of a cam (18) driven by a timer (3) ; the position of said olive (23) with respect to said pivoting plates (10, 11) permitting or not the activation of the slide (21) by means of an handling button (22) and as a consequence the on or off setting of the motor (2).

Description

The present invention relates to a remote control which can be used in particular for explosion-proof electric motors.

In certain applications, for example for controlling paint stirrers or other products containing volatile components, explosion-proof motors are used which are often placed in inaccessible places. It is therefore important to be able to control these electric motors remotely.

Furthermore, in the use under consideration, a mixer or other device must be driven for a well-defined period of time, so that the control must be provided with a timer to avoid having to constantly monitor it. It is also very important that the engine can be stopped immediately if an incident occurs and it is known in the art that particularly rapid intervention is obtained when a stop switch or button operating by pressing is available since an actuation known as a punch corresponds to an automatic reflex.

US-A-1 993 645 describes a mechanical system for triggering a spring device, for example for the control of a motor vehicle starter in which a low force allows the triggering of a powerful mechanism.

Patent GB-A-511,683 discloses an on-off-reverse-rotation control for an electric motor intended to work in an environment presenting danger of explosion, in which the transmission of movement between the manual control member and the electric on-off-inversion rotation control of the motor is carried out by pneumatic or hydraulic control in which means are provided to ensure safety from the danger of explosion. In particular, it is intended that the direction of rotation cannot be reversed as long as a danger situation exists.

US-A-4 259 878 describes a structure in which a mechanical element with longitudinal movement is also held in two stable positions by an elastic latch, which makes it possible to obtain two different effects corresponding to each of the two stable positions.

The present invention solves the problem set out in the foregoing by creating a new control which, in addition, prevents the engine from being restarted even by accidental operation. In addition, the engine can be stopped at any time during the operation of the timer. Furthermore, these results are obtained by using extremely simple and robust means.

According to the invention, the mechanical remote control for explosion-proof motors of the type in which a motor comprises an on-off control crank with elastic return connected by a member for transmitting a movement to a movable member which can be printed manually a reciprocating movement by the actuation of an operating button is characterized in that said movable member has the form of a slide having a groove and a thinned part having a shoulder, said slide being disposed between a first and second pivoting plates mounted on two axes parallel to each other and perpendicular to the sliding direction of the slide, said pivoting plates, normally subjected to thrusts tending to pivot them towards each other, being able to be actuated by a olive mounted in such a way that it can move in a longitudinal direction parallel to the direction of movement of the ram and disp also daring between said two pivoting plates, the first pivoting plate being able moreover to be subjected, by means of a range, to the action of a cam driven by a timer; the position of said olive relative to said pivoting plates allowing or not the actuation of the slide using an operating button and consequently starting or stopping the engine.

Various other characteristics of the invention will also emerge from the detailed description which follows.

• La figure 1 est une élévation en partie schématique d'un mécanisme de commande à distance d'un moteur électrique antidéflagrant.
• La figure 2 est une élévation vue sensiblement suivant la ligne II-II de la fig. 1.
• La figure 3 est une coupe vue suivant la ligne III-III de la fig. 1.
• La figure 4 est une coupe vue suivant la ligne IV-IV de la fig. 1.
• La figure 5 est une coupe partielle vue suivant la ligne V-V de la fig. 4.
• La figure 6 est une coupe vue suivant la ligne VI-VI de la fig. 1.
• La figure 7 est une élévation partielle analogue à la fig. 1 illustrant la commande dans une position caractéristique.
• La figure 8 est une coupe vue suivant la ligne VIII-VIII de la fig. 7.
• La figure 9 est une coupe vue suivant la ligne IX-IX de la fig. 7.
• La figure 10 est une coupe vue suivant la ligne X-X de la fig. 7.
• La figure 11 est une élévation partielle analogue à la fig. 7 illustrant une autre position caractéristique.
• La figure 12 est une coupe vue suivant la ligne XII-XII de la fig. 11.
• La figure 13 est une coupe vue suivant la ligne XIII-XIII de iafig. 11.
• La figure 14 est une coupe vue suivant la ligne XIV-XIV de lafig. 11.
• La commande illustrée au dessin est destinée à manoeuvrer une manivelle de commande marche-arrêt 1 d'un moteur électrique antidéflagrant 2. La manivelle 1 est normalement sollicitée par un ressort pour tourner dans le sens de la flèche f₁ (fig.1), c'est-à-dire dans le sens interrompant automatiquement l'alimentation du moteur 2.

An embodiment of the object of the invention is shown, by way of nonlimiting example, in the accompanying drawing.

• Figure 1 is a partly schematic elevation of a remote control mechanism of an explosion-proof electric motor.
• Figure 2 is an elevation seen substantially along line II-II of FIG. 1.
• Figure 3 is a sectional view along line III-III of FIG. 1.
• Figure 4 is a sectional view along line IV-IV of FIG. 1.
• FIG. 5 is a partial section seen along the line VV of FIG. 4.
• Figure 6 is a sectional view along line VI-VI of FIG. 1.
• FIG. 7 is a partial elevation similar to FIG. 1 illustrating the control in a characteristic position.
• Figure 8 is a sectional view taken along line VIII-VIII of FIG. 7.
• Figure 9 is a sectional view taken along line IX-IX of FIG. 7.
• Figure 10 is a sectional view taken along line XX of FIG. 7.
• FIG. 11 is a partial elevation similar to FIG. 7 illustrating another characteristic position.
• Figure 12 is a sectional view taken along line XII-XII of FIG. 11.
• Figure 13 is a sectional view along line XIII-XIII of iafig. 11.
• Figure 14 is a sectional view along line XIV-XIV of lafig. 11.
• The command illustrated in the drawing is intended for operate an on-off control crank 1 of an explosion-proof electric motor 2. The crank 1 is normally biased by a spring to turn in the direction of the arrow f ₁ (fig. ₁ ), that is to say in the direction automatically interrupting the supply of motor 2.

The operating time of the motor 2 must be controlled by a timer 3, the operation of which must only be taken into account after the crank 1 has been made to pivot in the opposite direction to the arrow f ₁ by a corresponding sufficient angle. on condition of engine “running” 2. Furthermore, the explosion-proof engine 1 must be able to be stopped instantly by means of a push button 4 of the so-called punch type.

As illustrated in the drawing (fig. 1), the control advantageously comprises a box 5 in which a support 6 made of sheet metal is fixed. This support forms a back 7 which is parallel to the front face 5a of the housing.

Figs. 1 and 2 show that the back 7 has openings 8 through which the legs 9 with arched ends 9a which are part of two plates 10 and 11 have passed. The legs 9 are held behind the back 7 by two springs 12, 13 constituted by piano strings, the ends of which are engaged behind the arched ends 9a of said legs, said springs also bearing at their middle part against projections 14, 15 formed from punctures in the back 7. The springs 12, 13 are prestressed so as to exert a thrust on the legs 9 and, consequently, so as to rotate the plates 10, 11 in the direction for which these plates tend to be brought closer to one another.

The plate 10 (fig. 3 for example) has a dropped edge 16 extending over part of its length as shown in dotted lines in fig. 1 and which is directed towards the plate 11. In addition, the plate 10 has a bearing surface 17 which is intended to cooperate with a cam 18 driven by the timer 3.

The plate 11 (fig. 4 for example) has on its side two fallen edges 19, respectively 20, offset relative to each other. The dropped edge 19 is intended to cooperate with a slide 21 which can be operated by a button 22.

The dropped edge 20 is intended to cooperate with an olive 13 having a flat 24, said olive being controlled by the pusher 4.

• 1. une position apparaissant aux fig. 5, 11 et 13 dans laquelle le bord tombé 20 de la plaque 11 prend appui directement sur la partie de petit diamètre de la tige 25 tandis que le bord tombé 16 de la plaque 10 prend appui sur le méplat 24 de l'olive 23. Dans cette position, le poussoir 4 est enfoncé, la tige 25 est verrouillée par les billes 27 entrant dans les rainures 26 (Fig. 5) et, fig. 11, 13 et 14, il n'est pas possible de mettre en route le moteur électrique 2. En effet, comme l'illustre le dessin, le coulisseau 21 qui peut être commandé par le bouton 22 présente une première partie 21a (fig. 10) de petit diamètre qui est raccordée à la partie 21 proprement dite par un épaulement 29 (fig. 11 et 14). Le coulisseau 21 présente, par ailleurs, une rainure 30 (fig. 10). L'épaulement 29 vient en butée contre le bord tombé 19 (fig. 14) si l'on cherche à tirer le bouton 22, ce qui empêche que le coulisseau 21 déplace un câble 31 (fig. 1) servant à l'actionnement de la manivelle 1. De même, le bord tombé 16 étant soulevé, il en est de même de la portée 17 et, par conséquent, celle-ci ne peut pas être actionnée par la came 18 de la minuterie 3 ;
• 2. une position apparaissant en particulier aux fig. 1,4 et 9 dans laquelle le poussoir 4 est tiré et a entraîné la tige 25 qui est alors verrouillée par les billes 27 entrant dans les rainures 26a (fig.5). Dans cette seconde position, le méplat 24 de l'olive 23 soulève le bord tombé 20 de la plaque 11. Cela libère le coulisseau 21 mais le ressort 12 applique le bord tombé 16 de la plaque 10 sur le corps 21 de ce coulisseau. La plaque 10 occupe par conséquent la même position que celle qu'occupait dans le cas décrit sous 1) ci-dessus, et la portée 17 ne peut pas non plus être actionnée par la came 18 de la minuterie 3.

As shown in fig. 5, the olive 23 is part of a rod 25 which connects it to the pusher 4 and which has in a manner known per se (see for example patent US-A-4 259 878) two grooves 26, 26a for locking balls 27 held by an elastic ring 28. Thus, the olive 23 can be immobilized in two positions, namely:

• 1. a position appearing in fig. 5, 11 and 13 in which the fallen edge 20 of the plate 11 bears directly on the small diameter portion of the rod 25 while the fallen edge 16 of the plate 10 bears on the flat 24 of the olive 23. In this position, the pusher 4 is depressed, the rod 25 is locked by the balls 27 entering the grooves 26 (Fig. 5) and, fig. 11, 13 and 14, it is not possible to start the electric motor 2. In fact, as illustrated in the drawing, the slide 21 which can be controlled by the button 22 has a first part 21a (fig. 10) of small diameter which is connected to the part 21 proper by a shoulder 29 (fig. 11 and 14). The slide 21 also has a groove 30 (fig. 10). The shoulder 29 abuts against the fallen edge 19 (fig. 14) if one seeks to pull the button 22, which prevents the slider 21 from moving a cable 31 (fig. 1) used for actuating the crank 1. Likewise, the dropped edge 16 being raised, the same is true of the bearing surface 17 and, consequently, the latter cannot be actuated by the cam 18 of the timer 3;
• 2. a position appearing in particular in FIGS. 1,4 and 9 in which the pusher 4 is pulled and has driven the rod 25 which is then locked by the balls 27 entering the grooves 26a (fig.5). In this second position, the flat 24 of the olive 23 raises the fallen edge 20 of the plate 11. This releases the slide 21 but the spring 12 applies the fallen edge 16 of the plate 10 to the body 21 of this slide. The plate 10 therefore occupies the same position as that occupied in the case described under 1) above, and the bearing surface 17 can also not be actuated by the cam 18 of the timer 3.

When it is desired to operate the motor 2, it is necessary to bring the pusher 4 to the second position described above, to pull the button 22 to bring it to the position shown in FIGS. 7 and 10, which causes the spring 12 to pivot the plate 10, so that the dropped edge 16 enters the groove 30 of the slide 21 which is thus locked, the bearing surface 17 coming against the cam 18 of the timer 3. The traction exerted on the button 22 brought the crank 1 into the position corresponding to the operating state of the motor 2.

When the time counted by the timer 3 has elapsed, the upper part of the cam 18 raises the span 17, which is shown in FIG. 3, so that the plate 10 is itself raised so that the dropped edge 16 escapes from the groove 30 by releasing the slide 21 which is brought back to the position illustrated in FIG. 1 by the elastic force exerted on the crank 1 in the direction of the arrow f _i . As a result, the engine stops.

The engine can be restarted by resetting the timer and pulling button 22 again.

Assuming now that the motor 2 is in operation, that is to say that the plate 10 maintains, by its fallen edge 16 engaged in the groove 30, the slide 21 in the position illustrated in FIG. 10 and that an incident occurs which requires the engine to be stopped immediately, it suffices to suddenly push the pusher 4 to bring it into the position illustrated in FIGS. 11 and 13, that is to say in which the edge fallen 16 from the plate 10 is raised and bears on the flat 24 of the olive 23 while the fallen edge 20 of the plate 11 comes to bear on the small diameter portion of the rod 25. In this case, the edge fallen 16 releases the groove 30 of the slide 21 to allow the crank 1 to return to the position corresponding to the stopping of the motor and the slide 21 can no longer be actuated from the button 22 since the fallen edge 19 of the plate 11 is then engaged with the shoulder 29. Resumption of operation is only possible after a new arming of the pusher 4.

The invention is not limited to the embodiment shown and described in detail, because various modifications can be made without departing from its scope. In particular, the cable 31 could be replaced by a hydraulic control.

Claims (8)

1. Mechanical remote control for anti-deflag- rating motors of the type in which a motor (2) comprises a resilient returning on-off control crankshaft (1) connected by a movement transmission means (31) to a mobile means (21) to which can be manually imparted a reciprocating motion by acting on an handling button (22), characterized in that said mobile means has the shape of a slide (21) having a groove (30) and a thinned portion (21a) with a shoulder (29), said slide (21) being placed between a first (10) and a second (11) pivoting plates mounted on two rods which are parallel to each other and perpendicular to the sliding direction of the slide (21), said pivoting plates (10, 11), normally urged for tending to make them to pivot the one towards the other, able to be activated by an olive (23) mounted so that it can move in a longitudinal direction which is parallel to the direction of movement of the slide (21) and also placed between said two pivoting plates (10, 11), the first pivoting plate (10) being further able to be submitted through a bearing (17) to action of a cam (18) driven by a timer (3) ; the position of said olive (23) with respect to said pivoting plates (10, 11) permitting or not the activation of the slide (21) by means of an handling button (22) and as a consequence the on or off setting of the motor (2).

2. Mechanical control according to claim 1, characterized in that the olive (23) is mounted on a rod (25) which can be locked in two distinct positions depending on the position occupied by a push member (4) and consequently by the olive (23) ; the first of these two positions permitting the on setting of the motor (2) provided that the olive (23) maintain in a raised position the second pivoting plate (11) which otherwise would prevent sliding of the slide (21) by means of a bent edge (19) that it has and which is placed to engage the shoulder (29) of said slide (21).

3. Mechanical control according to one of claims 1 and 2, characterized in that the crankshaft (1) for controlling the on-off setting of the motor (2) is maintained in the position corresponding to the setting of the motor (2) by the slide (21) locked by a bent edge (16) of the first pivoting plate (10) which is engaged in the groove (30) of said slide (21) and maintained in this position, when said slide is drawn, as long as said first plate (10) is not raised by the action of the cam (18), driven by the timer (3), on the bearing (17) of said first plate (10).

4. Mechanical control according to claims 1 to 3, characterized in that, in case of a difficulty, the activation of the push member (4) which handles the olive (23) may move said olive in the second position that it can occupy, in which the bent edge (16) of the second pivoting plate (11), which maintains the slide (21) in the position corresponding to the on state of the motor (2), is freed from the groove (30) of the slide (21) whereby the crankshaft (1), which controls the on-off setting of the motor (2) is brought back, by its resilient return, in the position corresponding to the off state of said motor while the second pivoting plate (11) maintained previously raised by the olive (23), can be lowered whereby the bent edge (19) of said second plate (11) becomes engaged with the shoulder (29) of the slide (21) by making thus impossible a new activation of said slide (21) - and consequently a new on setting of the motor (2) - except in the case the olive (23) has taken back the first of its two distinct positions, following a new triggering of the push member (4).

5. Mechanical control according to one of claims 1 to 4, characterized in that the two pivoting plates (10, 11) have articulation tabs (9) engaged in apertures (8) of the back (7) of a support (6), said tabs having bent over ends (9a) for delimiting notches for the ends of springs (12, 13) bearing on protrusions (14, 15) of a back (7) and exerting on said tabs (9a) pushes tending to make the plates (10, 11) to pivot the one toward the other.

6. Mechanical control according to one of claims 1 to 5, characterized in that the slide (21) is connected, in a manner know per se, to the crankshaft (1) which controls the on-off setting of the motor (2) by a calbe (31), an hydraulic transmission on similar means.

7. Mechanical control according to one of claims 1 to 6, characterized in that the plates (10, 11) are placed within a casing (5) on the front side of which are mounted the push member (4), the button (22) for activating the slide (21) and the timer (3).

8. Mechanical control according to one of claims 1 to 7, characterized in that the olive (23) which activates the plates (10, 11) in dependency of the position of the push member (4) has a flat (24) at its median part and, in a manner know per se, locking grooves (26, 26a) cooperating with a resilient lock (27, 28) permitting to maintain said olive (23) in said two stable and distinct positions.

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