WO2017009721A1

WO2017009721A1 - Lever actuator for controlling electrical devices

Info

Publication number: WO2017009721A1
Application number: PCT/IB2016/051900
Authority: WO
Inventors: Marco Pizzato; Simone Zonta
Original assignee: Pizzato Elettrica S.R.L.
Priority date: 2015-07-15
Filing date: 2016-04-04
Publication date: 2017-01-19
Also published as: EP3323135A1; CN106716291A; TR201906361T4; ITUB20152214A1; CN106716291B; EP3323135B1

Abstract

A lever actuator for controlling electrical devices comprises an anchoring body (2) for the anchorage to the panel or box of the device defining a central axis (X) and provided with drive means (5) adapted to engage the switching means of the electrical device, a control lever (7) having a lower end (8) pivoted on the anchoring body (2) to rotate around a fulcrum point (9) and selectively engage the drive means (5), a flexible sheath (10) for covering the lever (7) fixed to the anchoring body (2) by sealing means (3, 13), locking means (19) of the lever (7), unlocking means (26) comprising a releasing element (27) movable on the lever (7) between a locking position of the lever (7) wherein it engages the locking means (19) and an unlocking position wherein it is free therefrom to disengage the lever (7) from the locking means (19) and allow the rotation thereof. The flexible sheath (10) is a unitary body which entirely covers the lever (7) and the release element (27) seamlessly. The unlocking means (26) comprise a gripping element (28) coupled to the releasing element (27) with the interposition of the sheath (10) to allow gripping of the unlocking means (26) by a user adapted to promote the movement of the releasing element (27) from the locking position to the unlocking position.

Description

LEVER ACTUATOR FOR CONTROLLING ELECTRICAL DEVICES

Description

Technical Field

The present invention finds application in the field of electrical devices for industrial use and it particularly relates to a lever actuator adapted to be coupled to electrical controlling or commanding devices of machines or industrial plants. In particular, the actuator is connectable to electrical devices provided with panels and/or control push-button for controlling a power supply or service circuit of a machine or industrial plant.

State of the art

The push-button units and the panels for controlling machines or industrial plants are electrical devices provided with one or more actuators adapted to operate corresponding movable contacts housed inside a box or placed inside an electric panel for switching one or more power supply or service circuits of the machine or plant.

The actuators adapted to be applied to the push-button unit or panel may be of different types depending on the type of command to be sent.

One of these actuators can be constituted by a joystick-type lever whose movement in one or more directions causes a predetermined action of the machine or plant.

For example, a typical action controlled by a lever actuator provides for the movement of the machine or part of the plant in a predetermined direction.

In general, the control levers comprise a rod pivoted at its lower end so that the handling of the rod produces the operation of one or more corresponding electrical contacts.

The stem is also covered by a bellows sheath whose aim is to protect the internal components from dirt and/or liquids depending to the safety degree needed for the device, as disclosed for example in WO2005/043 269.

In some embodiments the lever is provided with a locking/releasing device that operates when the rod is in a central position to prevent accidental movements thereof.

In this way, to operate the command the operator have to act on the device in order to obtain the release of the stem.

Typically, the releasing of the stem is obtained by translating an unlocking element upwards or downwards so as to disengage it from an appropriate locking element.

However, the solutions provided with sheath and locking/releasing device, such as the one disclosed in EP1808738, are affected by some drawbacks that make them not safely usable within dusty environments or where there is risk of contact with liquids.

As matter of fact, these solutions require the presence of a top key to press or a lateral ring to pull that, however, provide for a break of the continuity of the outer sheath, thus creating areas of potential entry of water and dirt and making necessary the use of additional means to ensure the liquid-tight seal, such as inner gaskets.

Scope of the invention

The object of the present invention is to overcome the above mentioned drawbacks, by providing a lever actuator for controlling electrical devices that is high efficient and relatively cost-effective.

A particular object is to provide a lever actuator for controlling electrical devices provided with central position block and which is compact, sturdy, and which may ensure the best possible protection against entry of water and dirt, to be classified at least IP67 according to IEC 60529.

A particular object is to provide a lever actuator for controlling electrical devices which is of simple construction and easy to assemble.

These objects, as well as others which will become more apparent hereinafter, are achieved by a lever actuator for controlling electrical devices that, according to claim 1, comprises an anchoring body for anchoring to a panel or box of an electrical device, said anchoring body defining a central axis and being provided with drive means adapted to interact with the switching means of the electric device, a control lever having a lower end pivoted on said anchoring body to rotate around a fulcrum point and interact selectively with said drive means, a flexible sheath for covering said lever, said sheath being closed at the top and having a lower open edge fixed to said anchoring body by sealing means, locking means of said lever in axial position adapted to prevent the rotation thereof around said fulcrum point, unlocking means comprising a releasing element movable in said lever between a locking position of said lever wherein engages said locking means and an unlocking position wherein it is free therefrom to disengage said lever from said locking means and allow its rotation.

The flexible sheath is a unitary body which entirely covers said lever and said releasing element without breaking the continuity thereof.

Moreover, said unlocking means comprise a gripping element coupled to said releasing element with the interposition of said sheath to allow said unlocking means to be gripped by a user to promote the movement of said releasing element from said locking position to said unlocking position.

Thanks to this combination of features, it will be possible to provide an actuator suitably protected from dirt and liquids, thanks to the presence of a sheath that covers entirely the sensitive parts, and at the same time also provided with a releasing device whose positioning does not compromise the integrity of the sheath nor requires that the same sheath should be formed by two or more parts non-unitary with each other.

Suitably, said releasing element may comprise a movable cylindrical rod slidingly inserted on said lever to slide between said locking and unlocking positions.

Advantageously, said cylindrical rod may comprise a peripheral groove defining a housing seat for said gripping element and for their mutual coupling with the interposition of said sheath.

The gripping element may comprise a ring having an inner peripheral edge with an annular radial projection adapted to be inserted into said peripheral groove of said rod with the interposition of said sheath.

In this way the coupling between the gripping element and the rod will be stable and safe during the whole sliding of the movable rod.

Moreover, said sheath may be shaped as a bellows with an annular peripheral portion shaped to be inserted into said peripheral groove of said rod and having an outer peripheral groove adapted to snugly fit the radial projection of said ring.

The shape of the sheath will allow it to be stably coupled to the rod and at the same time to provide for the correct positioning of the gripping element that will not deform excessively the sheath, while preserving the integrity during time.

In addition, the gripping element will not interfere with the movement of the sheath, which may deform and return in the undeformed position without having particularly stressed areas and behaving as if the gripping element was not present.

However, the coupling between the gripping element and the movable rod will be adequately stable even in the absence of the groove in the sheath and/or of the groove of the rod as only consequence of the compression of the suitably sized gripping element on the sheath itself other than on the rod.

Advantageously, said ring may be formed from two half-rings fastened to each other in a removable manner, so as to position the ring in a simple and rapid manner after the assembly of the sheath, being able to also use sheaths suitable for use with control lever devices without block.

Suitably, said gripping element may comprise a closing disc snap coupled with said half-rings in order to stabilize the mutual coupling.

Advantageous embodiments of the invention are obtained in accordance with the dependent claims.

Brief disclosure of the drawings Further features and advantages of the invention will become more apparent in light of the detailed description of a preferred but not exclusive embodiment of a lever actuator for controlling electric devices, shown by way of non-limiting example with the aid of the accompanying drawings, wherein:

FIG. 1 is an elevated view of the actuator;

FIG. 2 is an axially sectioned view of the actuator of Fig. 1;

FIG. 3 is an exploded elevated view of the actuator of Fig. 1;

FIG. 4 is an exploded elevated view of a detail of the actuator of Fig. 1;

FIG. 5 is a sectioned view of the actuator of Fig. 1 in an operating sequence.

Best mode of carrying out the invention

With reference to the accompanying drawings, a preferred but not exclusive embodiment of a lever actuator for controlling electrical devices is shown, which is adapted to be applied to a control panel or to a box or push-button unit for controlling machines or industrial plants, not shown as known per se.

In particular, the actuator may be movably connected to a panel or box of a push-button unit of an electrical device for controlling or operating a machine or plant for interacting with the switching means connected to one or more control circuits of the machine or plant and produce an action in function of the moving direction.

In a typical way, the actuator may be used for moving a machine or a part of a plant along one or more predetermined directions.

Fig. 1 shows the actuator in the assembled condition, generally indicated by 1, comprising an anchoring body 2 having a substantially cylindrical shape and defining a central axis X and designed to be removably anchored to the panel or box of the electric device.

In a known manner, the anchoring body 2 will be designed to be inserted in a hole of the panel or box having an appropriate diameter to be locked on the panel or box by means of a ring nut or similar fixing element, not shown as known per se, adapted to be screwed on the threaded surface 4 of the anchoring body 2.

It is however understood that the anchoring body 2 may be provided with means for fixing to the panel or box also different from those illustrated, according to any of the techniques known in the art.

As more visible from the section of Fig. 2, the anchoring body 2 internally houses drive means 5 adapted to interact with the switching means, not shown, of the electric device.

The drive means 5 comprise one or more sliders 6 axially sliding in the anchoring body 2 to interact with respective switching means and imparting a predetermined command. In the shown embodiment four sliders 6 are arranged in positions mutually angled at 90 degrees from each other to operate on corresponding switching contacts and generate a movement of the machine or plant along corresponding directions.

It is clear, however, that their number and mutual arrangement may vary depending on the intended use of the actuator 1.

The actuator 1 also comprises a control lever 7 having a lower end 8 pivoted on the anchoring body 2 to rotate around a fulcrum point 9 and be arranged in one or more inclined positions with respect to the central axis X so as to selectively interact with one of the sliders 6.

The lever 7 is completely covered by a bellows-shaped flexible sheath 10 formed as a unitary body, generally made of soft plastic, which extends seamlessly from a closed top wall 11 to an open lower edge 12.

This latter is fixed to the anchoring body 2 by sealing means, comprising for example a fastening ring 13 adapted to be applied to the anchoring body 2 to lock the lower edge 12 of the sheath 10 thereon and protect the anchoring body 2 from entry of liquids and dirt.

The drive means 5 also comprise a disk-like operating element 14 with a central hole 15 for the insertion of the lower end 8 of the lever 7.

The operating element 14 has one or more lateral projections 16 that extend downward to engage respective axial sliders 6 and a central projection 17 with a rounded shape coupled to a complementarily shaped rolling surface 18 provided in the anchoring body 2, so as to define the fulcrum point 9.

The anchoring body 2 internally house, at least partially, locking means 19 of the lever 7 in the central axial position, suitable to prevent the rotation around the fulcrum point 9.

As most clearly visible from Fig. 3, the locking means 19 comprise a cap 20 fixed to the anchoring body 2 by means of the fastening ring 13 and having a peripheral wall 21 with an outer peripheral groove 22 adapted to house the open lower base 12 of the sheath 10.

The fastening ring 13 will be designed to be applied on the upper edge 23 of the anchoring body 2 to lock the lower edge 12 of the sheath 10 on the cap 20.

Moreover, a further seal 46 will be suitably provided to be interposed between the anchoring body 2 and the panel or the lid of the box of the pus-button unit.

In addition, as more evident from the enlarged view of the detail of Fig. 2, the sealing means also comprise a small tooth 3 which extends over the whole or part of an annular surface of the anchoring body 2 designed to allow the lower open edge 12 of the sheath 10 to lean thereon. In this way the tooth 3 may penetrate into the material of the sheath 10 in order to obtain the tight coupling with the anchoring body 2.

The cap 20 also comprises a central passage 24 for the lever 7 and one or more radial slots 25, four in the shown embodiment, made in its peripheral wall 21 and connected to the central passage 24 to allow the rotation of the lever 7 along respective predetermined directions, so as to make possible the interaction with a corresponding slider 6.

The lever 7 is associated with unlocking means 26 which allow the guided displacement from the axial position to be rotated and inserted in any of the slots 25 of the cap 20.

In particular, the unlocking means 26 comprise a releasing element 27 movable on the lever 7 and entirely housed in the sheath 10 move between a locking position of the lever 7, wherein the releasing element 27 engages the locking means 19, and an unlocking position wherein the releasing element 27 is free from the locking means 19 to disengage the lever 7 from the latter and allow the rotation thereof.

The unlocking means 26 also comprise a gripping element 28 arranged externally to the sheath 10 and adapted to be grasped by a user to promote the movement of the movable releasing element 27 from the locked position to the unlocked position, as will be described in more detail hereinafter.

The releasing element 27 comprises a seat 29 for housing the gripping element 28 and their mutual coupling with the interposition of the sheath 10.

In particular, the releasing element 27 comprises a cylindrical rod 30 slidably inserted on the lever 7 to slide between the locking position wherein it is at least partially inserted in the central passage 24 of the cap 20 and the unlocking position wherein it is completely outside the locking cap 20.

The cylindrical rod 30 has a peripheral groove defining the housing seat 29 for the gripping element 28.

This latter comprises a ring 31 having an inner peripheral edge 32 with an annular radial projection 33 adapted to be inserted into the peripheral groove 29 of the rod 30 with the interposition of the sheath 10.

In turn, the bellows-shaped sheath 10 has a peripheral annular portion 34 shaped to fit into the peripheral groove 29 of the rod 30 and having an outer peripheral groove 35 adapted to snugly fit the radial projection 33 of the ring 31.

As shown form Fig. 4, the ring 31 is formed by two half-rings 36 mutually fastened in a removable manner, for example by means of respective pins 37 protruding from one of the front walls to be inserted into corresponding holes 38 of the other half -ring 36. The coupling between the two half-rings 36 is made stable by an annular closure element 39 snap coupled or coupled by bayonet means with the half-rings 36.

In a not shown variant, the sheath 10 may be devoid of the peripheral groove 35 as the coupling with the annular gripping element 28 may be obtained following the only mutual coupling of the two half-rings 36 or by the compression effect produced thereon by a grasping element annular differently shaped, for example made in one piece. For the same reason, the rod 30 may be devoid of the peripheral groove 29.

Fig. 5 shows a typical unlocking and moving sequence of the lever 7.

In particular, in Fig. 5a) the lever 7 is shown in the central axial locked position, wherein the movable rod 30 is in the locking position and partially inserted in the central passage 24 of the cap 20, preventing the movement of the lever 7 because the diameter of the rod 30 is greater than the width of the radial slots 25 of the cap 20.

In Fig. 5b) the rod 30 is pulled by means of the gripping element 28 towards the unlocking position wherein it is extracted from the cap 20.

In this movement the rod 30 operates against the elastic force of a first elastic element 40 fixed on the opposite side to a fixed head 41 coupled to the upper end 42 of the lever 7.

The first elastic element 40, for example a coli spring, will have the task of pushing the movable rod 30 toward the locking position as the gripping element 28 is released.

As soon as the rod 30 will be extracted from the cap 20 it will be possible to rotate the lever 7 around the fulcrum point 9 by inserting it into one of the slots 25 and causing the contact between one of the lateral projections 16 of the disk-like operating element 14 and the corresponding slider 6, which in turn will engage with one or more switching contacts of the electrical device.

The lever 7 will also be provided with elastic return means 43 adapted to return it in the axial position upon its release by the user.

The elastic return means 43 comprise a wedge 44 which acts against the inner surface of the cap 20 under the action of a second elastic element 45.

Following the rotation of the lever 7 the wedge 44 moves downwards compressing the second elastic element 45, so that the action of elastic return of the latter promotes the upward sliding of the wedge 44 on the inner surface of the cap 20 and the return of the lever 7 in the axial position.

From above it appears evident that the actuator according to the invention reaches the intended objects and in particular to ensure high protection against entry of dirt and water even in the presence of locking means of the lever in the central position. The actuator according to the invention is susceptible of numerous modifications and variations, all falling within the inventive concept expressed in the accompanying claims. All the details may furthermore be replaced with other technically equivalent elements, and the materials may be different according to requirements, without departing from the scope of protection of the present invention.

Even if the actuator has been disclosed with particular reference to the attached figures, the reference numbers used in the description and in the claims are used to improve the intelligence of the invention and do not constitute any limitation to the scope of protection claimed.

Claims

1. A lever actuator for controlling electrical devices, wherein an electrical device comprises a support panel or box and switching means adapted to be connected to a control circuit of a plant or machine, which actuator comprises:

- an anchoring body (2) for the anchorage to the panel or box of the device, said anchoring body (2) defining a central axis (X) and being provided with drive means (5) adapted to engage the switching means of the electrical device;

a control lever (7) having a lower end (8) pivoted on said anchoring body (2) to rotate around a fulcrum point (9) and selectively engage said drive means (5);

- a flexible sheath (10) for covering said lever (7), said sheath (10) being closed at the top and having an open lower edge (12) fixed to said anchoring body (2) by sealing means (3, 13);

locking means (19) of said lever (7) in an axial position adapted to prevent rotation thereof about said fulcrum point (9);

- unlocking means (26) comprising a releasing element (27) movable on said lever (7) between a locking position of said lever (7) wherein it engages said locking means (19) and an unlocking position in which it is free therefrom to disengage said lever (7) from said locking means (19) and allow the rotation thereof;

characterized in that said flexible sheath (10) is a unitary body which entirely covers said lever (7) and said release element (27) seamlessly, said unlocking means (26) comprising a gripping element (28) coupled to said releasing element (27) with the interposition of said sheath (10) to allow gripping of said unlocking means (26) by a user adapted to promote the movement of said releasing element (27) from said locking position to said unlocking position.

2. Actuator as claimed in claim 1, characterized in that said releasing element (27) comprises a movable cylindrical rod (30) slidingly inserted on said lever (7) to slide between said locking and unlocking positions.

3. Actuator as claimed in claim 2, characterized in that said cylindrical rod (30) comprises a peripheral groove (29) defining a seat for housing said gripping element (28) and for their mutual coupling with the interposition of said sheath (10).

4. Actuator as claimed in claim 2 or 3, characterized in that said gripping element (28) comprises a ring (31) having an inner peripheral edge (32) with an annular radial projection (33) adapted to be inserted into said peripheral groove (29) of said rod (30) with the interposition of said sheath (10) so that said ring (31) radially compresses said sheath (10) and firmly couple with said cylindrical rod (30).

5. Actuator as claimed in claim 4, characterized in that said sheath (10) is bellows-shaped with an annular peripheral portion (34) shaped to fit into said peripheral groove (29) of said rod (30) and having an outer peripheral groove (35) adapted to snugly fit said radial projection (33) of said ring (31).

6. Actuator as claimed in claim 4 or 5, characterized in that said ring (31) is formed by two half -rings (36) mutually fastened and stably coupled by means of an annular closure (39).

7. Actuator as claimed in any claim from 2 to 6, characterized in that said releasing element (27) comprises a fixed head (41) coupled to the upper end (42) of said lever (7) and a first elastic element (40) interposed between said fixed head (41) and said movable rod (30) and adapted to push the latter towards said locking position upon the unlocking of said gripping element (28).

8. Actuator as claimed in any preceding claim, characterized in that said drive means (5) comprise one or more sliders (6) axially sliding in said anchoring body (2) to engage with respective switching means of the electric device.

9. Actuator as claimed in any preceding claim, characterized in that said anchoring body (2) comprises an annular surface for supporting said open lower edge (12) of said sheath (10), said sealing means comprising an annular tooth (3) projecting axially from said annular supporting surface to penetrate at least partially in the material of said sheath (10).

10. Actuator as claimed in any preceding claim, characterized in that said locking means (19) comprise a cap (20) fixed in said anchoring body (2) by said sealing means (13) and having a peripheral wall (21) with an external peripheral groove (22) adapted to receive an edge of the lower end of said sheath (10) and a central passage (24) for said lever (7), said peripheral wall (21) also comprising one or more radial slots (25) connected with said central passage (24) to allow rotation of said lever (7) according to predetermined respective directions and its interaction with a corresponding slider (6).