FR2763663A3 - DUAL AUTHORIZATION OPERATING DEVICE, PARTICULARLY FOR HEDGE TRIMMERS AND THE LIKE - Google Patents

Abstract

This device is of the type comprising blades of size L actuated by an electric motor M housed in a casing T, in which this device comprises two authorization elements 2, 4, which can be actuated separately to act selectively on at least one switch S for supplying the motor, and braking means 8 able to act on a rotating part 6 connected to the blades L when at least one of the authorization elements 2, 4 is released. It comprises a tilting member 7 coupled in an operational manner to the authorization elements 2, 4 to control both the switch (s) S and the braking means.

Description

Double authorization actuation device.

  in particular for hedge trimmers and similar tools Field of application The present invention finds an application in the sector of garden tools and in particular hedge trimmers and relates specifically to a double authorization actuation device for a safe switching on and off of said

tools.

  STATE OF THE ART In order to comply with the safety standards in force, hedge trimmers and electric garden tools currently on the market must be fitted with suitable actuating devices which require the use of both hands by the user. To this end, said devices provide two separate controls which must be activated simultaneously to obtain start-up.

of the instrument.

  Said controls are normally of the mechanical type and consist of two elements accessible from the outside which, by means of linkage and return lever mechanisms which are complex, act separately on a single switch arranged

  in series in the motor supply circuit.

  This solution has the drawback of requiring numerous components of small dimensions and limited tolerances which must be mounted in relatively small spaces, with the difficulty of

resulting assembly.

  In accordance with another safety standard, tools with a free blade must also provide rapid stop devices, that is to say devices which block the movement of the pruning blades, and therefore of the electric motor which drives them, within a few seconds of the interruption of the power supply. For this purpose, braking means are provided which act on the engine or on moving parts driven by it. The braking devices used today can be of the electrical type, for example for short-circuiting the rotor, or of the mechanical type with free wheel and locking control. The former have the drawbacks of requiring the use of relatively complex cabling, of presenting premature wear of the collector and in addition of requiring the

  synchronization of the two switches.

  All current braking devices are relatively complex and cost a lot of money.

realization and assembly.

  SUMMARY OF THE INVENTION The general aim of the present invention is to remedy the drawbacks mentioned above by producing an actuation device with double control, of high safety and reliability and

relatively low cost.

  A particular aim within the framework of the general aim is to provide a dual control actuation device which is capable of guaranteeing maximum safety conditions both at start-up and at

shutdown.

  Another object is to reduce the number of components and the complexity of production and mounting of both the starting device and

of the braking device.

  These aims, as well as others, which will emerge better from the following, are obtained by a double authorization actuation device, in particular for hedge trimmers and similar tools, of the type comprising pruning blades actuated by a motor. electric housed in a casing, in which this device comprises two authorization elements, which can be actuated separately to act selectively on at least one engine power switch, and braking means capable of acting on a connected rotating part to the blades when at least one of the authorization elements is released, characterized in that it comprises a tilting member operatively coupled to the authorization elements for controlling both the one or more

  switches as the braking means.

  Thanks to this arrangement, the actuation device will be made up of a minimum number of components of low cost and high reliability. The tilting member is carried inside the casing so as to be able to oscillate and / or slide between a first closed position of the switch or switches, in which the braking means are inactive, and a second open position of the or electrical switches in which the

braking means are active.

  Preferably, the tilting member comprises a central axis from which extend, in a direction substantially perpendicular to the geometric axis of the axis, two arms each capable of cooperating

  with a respective authorization element.

  The authorization elements may consist of two levers or pushers with a tip mounted tilting or housed in a sliding manner inside the casing and comprising internal parts cooperating with free ends.

  respective arms of the tilting member.

  The central axis has end portions housed in buttonhole seats formed in the casing, or integral with the latter, with a possibility of rotation and translation in a direction substantially perpendicular to the geometric axis of the axis . The dual authorization actuation device according to the invention may also have one or more of the following features - elastic opposition means are provided acting on the axis to hold it towards the bottom of the buttonhole seats, a forced manner resting on the rotating part, - the rotating part consists of a disc or ring of material with a high coefficient of friction wedged on the motor rotor, the braking means are constituted by the external cylindrical surface of the axis which faces the disc of material with a high coefficient of friction, - the tilting member is operatively coupled to the pusher of the electric switch by means of an intermediate actuating member, - the intermediate actuating member consists of an L-shaped lever mounted tilting on a geometric axis substantially parallel to the axis and comprising end parts which cooperate respectively with the rocking member and the pusher, - the intermediate connecting member consists of a projecting part of the rocking member which directly faces the pusher of the electric switch.

Brief description of the drawings

  Other features and benefits of

  the invention will become apparent from the description

  detailed view of a preferred, but not exclusive, embodiment of a double authorization actuation device, in particular for hedge trimmers and similar tools, which is made with reference to the appended drawings, of which: FIG. 1 represents a view schematic of the device according to the invention applied to a hedge trimmer tool, partially in section through a longitudinal plane, FIG. 2 represents a transverse section of the device of FIG. 1 along the line II- II, FIG. 3 represents a view schematic of the device of the preceding figures, partially in section through a longitudinal plane, in a first operational position, FIG. 4 represents a schematic view of the device of FIG. 3, partially in section through a longitudinal plane, in a second operational position, the 5 shows a schematic view of the device of Figure 3, partially in section through a longitudinal plane, in a third position ion operational and Figure 6 shows a schematic view of the device of Figure 3, partially in section through a longitudinal plane, in a fourth position

operational.

  Description of an exemplary embodiment

  If we refer to the figures shown, a double-control actuation device, generally designated by the reference 1, is applied to a hedge trimmer U of the type comprising an outer casing T formed of two half-shells which serve to internally house an electric motor M used to drive size L blades. The electric motor M is connected to a power cable by means of a microswitch S provided with a pusher P. The device 1 comprises two authorization elements consisting of a first lever 2, mounted rocking at 3 along the edge of a rear handle of the housing T, and a second lever 4 mounted rocking at 5 on the front part of the housing T in the vicinity d 'a grab handle. The levers 2, 4 can be kept in the rest position using suitable elastic means, for example helical springs. Alternatively, the authorization means could consist of pushers sliding the

  along suitable seats, not shown in the drawings.

  Braking means are provided acting on a rotating part of the tool operatively coupled to the blades of the tool, in order to be able to block them within a few seconds from the interruption of the electrical supply to the motor. In particular, such braking means consist of a disc or ring 6 made of a material with a high coefficient of friction, wedged on the rotor R of the motor M, preferably anchored on the upper face of the fan V. According to the invention , a tilting member is provided, designated as a whole by the reference 7, which is actuated by the levers 2, 4 to control both the switch S and the braking means. Advantageously, the tilting member 7 can oscillate and / or slide between a first position for closing the switch S, in which the braking means are inactive, and a second position for opening the electric switch in which

the braking means are active.

  In particular, the tilting member 7 consists of a central transverse axis 8 from which extend, from opposite parts and in a direction substantially perpendicular to the geometric axis of the axis, two longitudinal arms 9, having curved end parts 11, 12 intended to cooperate with internal parts 13,14

respective levers 2, 4.

  The axis 8 has end portions 14, 15 housed in buttonhole seats 16, 17 respectively formed in the inner walls of the housing T or in

  side supports anchored to it.

  Advantageously, the buttonhole seats 16, 17 have a width slightly greater than the diameter of the axis and a main dimension directed perpendicularly

to the geometric axis of it.

  Electrical means, constituted for example by a leaf spring 18, are interposed between the upper wall of the casing T and the axis 8 to maintain the external surface of this axis 8 applied by force

normally to disk 6.

  Thus, under conditions of rest, the axis 8 will exert, on the disc 6 and therefore on the motor M, a braking action which will block it in a period of time which will depend on the tension adjustment of the spring 18. By actuating one and the other of the two levers 2, 4, we will obtain a distance from the axis 8 against the action of the spring 18, which interrupts the action

brake on disc 6.

  The tilting member 7 is operatively coupled to the pusher P of the electric switch S via a member

intermediate actuation.

  Said intermediate member preferably consists of a lever 19 in L mounted tilting on a geometric axis 20 substantially parallel to the geometric axis of the axis 8. One end of the lever 19 is articulated on the axis with a certain play of so as to follow this axis in its rotational and / or translational movement along the buttonhole seats 16, 17, while the opposite end faces the pusher P. As a variant, the intermediate actuating member could be constituted by a projecting part formed or attached to one of the arms, which is not shown in the drawings and made directly

  facing the pusher P, or on the axis 8 itself.

  Thus, the simultaneous actuation of the levers 2, 4 will determine the rotation of the lever 19 and the depressing of the normally open pusher P, so as to supply the motor M. In operation, by rotating the lever 2 counterclockwise and the lever 4 clockwise, a rotational and translational movement of the rocking member 7 is obtained, with a rotation of the lever 19, which results therefrom, which is sufficient to apply pressure to the pusher P and therefore to put the engine M running, as is easily understood

from Figure 1.

  Simultaneously, the actuation of one and the other of the levers 2, 4 causes the axis 8 to move away from the disc 6, so as to remove the braking action which blocks the motor, as is

  clearly shown in Figure 6.

  It is observed that the actuation of only one of the levers 2, 4, as shown in FIGS. 4 and 5, is not sufficient to distance the axis 8 from the disc, which still maintains the braking action. neither on it, nor to cause actuation of the push-button P on the switch S. The dual-control actuation device is susceptible to numerous modifications and variants all coming within the framework of the concept

  inventive expressed by the appended claims. All

  details may be replaced by technical equivalents which are also intended to be protected. The materials, shapes and dimensions could be any materials, shapes and dimensions in

according to requirements.

Claims (11)

  1. Double authorization actuation device, in particular for hedge trimmers and similar tools, of the type comprising size blades (L) actuated by an electric motor (M) housed in a casing (T), in which this device comprises two authorization elements (2, 4), which can be actuated separately to act selectively on at least one switch (S) for supplying the motor, and braking means (8) capable of acting on a rotating part (6) connected to the blades (L) when at least one of the authorization elements (2, 4) is released, characterized in that it comprises a tilting member (7) operatively coupled to the elements d authorization (2, 4) to order both the   the switches (S) as the braking means.   2. Actuating device according to claim 1, characterized in that the tilting member (7) is carried inside the casing (T) so as to be able to oscillate and / or slide between a first closed position of the or switches (S), in which the braking means (8) are inactive, and a second opening position of the electrical switch (s) in which the means braking are active.   3. actuation device according to claim 1, characterized in that the tilting member (7) comprises a central axis (8) from which extend, in a direction substantially perpendicular to the geometric axis of the axis , two arms (9, 10) each capable of cooperating with an element   respective authorization (2, 4) respective.   he 4. Actuating device according to claim 3, characterized in that the authorization elements (2, 4) consist of two levers or pushers with an end pivotally mounted or housed in a sliding manner inside the casing and comprising internal parts (13, 14) cooperating with free ends (11, 12) respective to the   arm (9, 10) of the tilting member (7).   5. actuation device according to claim 3, characterized in that the central axis (8) has end portions (14, 15) housed in buttonhole seats (16, 17) formed in the housing (T ) with a possibility of rotation and translation in a direction substantially   perpendicular to the geometric axis of the axis (8).   6. An actuating device according to claim 5, characterized in that there is provided elastic opposition means (18) acting on the axis (8) to hold it towards the bottom of the buttonhole seats (16, 17 ), forcibly pressing the rotating part (6).   7. actuating device according to claim 6, characterized in that the rotating part (6) consists of a disc or ring of material with a high coefficient of friction wedged on the motor rotor (R) (M).   8. An actuating device according to claim 7, characterized in that the braking means are constituted by the outer cylindrical surface of the axis (8) which faces the disc (6) of   material with a high coefficient of friction.   9. Actuation device according to   claims, characterized in that the organ   tilting (7) is operatively coupled to the pusher (P) of the electrical switch (S) by means   an intermediate actuator.   10. An actuating device according to claim 9, characterized in that the intermediate actuating member consists of an L-shaped lever (19) mounted tilting on a geometric axis (20) substantially parallel to the axis (8 ) and having end portions which cooperate respectively with   the tilting member (7) and the pusher (P).   11. Actuating device according to claim 9, characterized in that the intermediate connecting member consists of a projecting part of the tilting member which faces directly   the push button (P) of the electric switch (S).