Miniaturized circuit-breaker switch

Claim 2

In a single-pole circuit-breaker switch for manual operation and free tripping of the type comprising an insulating casing, two stationary contacts disposed in said casing, a hand-operated closure push-button slidably fitted within said casing and projecting therefrom, means for retaining said push-button in a depressed position, two movable contact means co-operating with said stationary contacts, and connected one to the other through the two arms of a U-shaped thermostatic element means, and elastic restoring means for returning the movable parts in the opening position at the time of operation of releasing means controlled by said thermostatic element, the improvement which consists in that said movable contact means are carried by a frame slidably moving within said casing, said frame being linked to said push-button through a pivoting connection member, said frame being lockable by a lock acting on said connection member during the time of depression of said push-button, said thermostatic element contacting a pivoting lever arranged so as to release said lock at the time of deformation of the said thermostatic element and allow said sliding frame to move under the action of said restoring means.

Claim 3

A circuit-breaker switch according to claim 6, wherein said insulating casing comprises two identical hollowed-out shells having an axial and a lower groove, and wherein said two stationary contacts respectively engage in saiD lower groove of the casing shells, an insulating positioning unit for maintaining said contacts in spaced relation; a guide sleeve rigidly fixed to a top portion of the casing and having a threaded portion thereon whereby the apparatus can be attached to a panel by means of a nut; said control push-button being formed of three assembled insulating components which are at least partially housed and guided within said guide sleeve; an operating blade attached to and extending below the base of the control push-button, said blade having an inclined groove in the lower portion thereof; said movable frame comprising two symmetrical right-angle brackets of cut-out and folded sheet metal to form flanges, said brackets being disposed in the form of a T and assembled by means of two spacer members, one of the spacer members being provided with a central internally threaded bore oriented in the axial direction, a lug means which is formed on each flange of the right-angle brackets and adapted to engage in said axial groove of a corresponding half-casing for vertically guiding the assembled frame; an operating arm comprising two superposed side-plates disposed on each side of said operating blade and respectively joined together at upper and lower ends thereof by means of an upper and lower cross pin, said upper cross pin defining a retaining pin and being engaged in said inclined groove of said operating blace whereby axial force exerted on the blade applies a radial force component to said upper cross-pin, and wherein the extremities of said lower cross-pin are engaged in a double-slope groove provided in each bracket of the movable frame, said lower cross-pin defining an actuating pin; an insulating guide for the retaining pin and a retaining plate means which are juxtaposed and stationarily fixed beneath the guide sleeve and forming an assembly having a central opening of dimensions permitting the passage of the operating blade and operating arm and preventing the passage of the retaining pin, a ramp disposed on each side of the opining and terminating in a recess, wherein said locking means comprises a latch pivotally disposed about a pin carried by the brackets of the movable frame, said latch being provided on one side of said pin with a bearing nose and on the other side of said pin with a heel-shaped projection means for retaining said actuating pin and a finger means for replacing the latch in a normal position, a trip lever means pivotally mounted on a further pin carried by the brackets of the movable frame and provided with a heel an insulating stud forming part of said thermostatic element and loop-spring means for urging said heel against said stud for determining as a function of current intensity which passes through the element the angular position of a retaining nose which cooperates with said bearing nose of said latch; an insulating contact-holder, means for positioning said contact-holder including a base member housed within a recess formed in the brackets of the movable frame and side-plates of said contact-holder applied against external faces of said brackets; an assembly plate for securing the contact-holder, said assembly plate carrying two projecting lug means for engagement in the axial guiding grooves of the casing; two movable and flexible S-shaped contact-holder strips centrally attached to the side plates of the insulating contact-holder and cooperating with the stationary contacts; said thermostatic element being constituted by a U-shaped bimetallic strip surrounding the movable frame for producing action on the heel of the trip lever, wherein the two arms of the U are respectively joined to upper extremities of the flexible strips for providing a direct electric circuit; an element means for providing compensation for ambient temperature constituted by two identical bimetallic strips having a double elbow with one extremity of each strip being clamped at a point of assembly of said thermostatic element and flexible strips and with the other extremIty being mechanically clamped between two small insulating plates for producing action on the thermostatic element; an adjusting screw means carried by the movable frame for bringing the thermostatic element into a position corresponding to a calibration value; a blade-spring means for maintaining the assembly plate on the movable frame and for permitting oscillation and axial displacement of the compensating element; and wherein said restoring means includes a compression spring housed within an axial bore formed in the stationary-contact positioning unit for reacting with the assembly plate and thrusting back the movable frame towards the top of the casing.

Claim 4

A single-pole circuit-breaker switch according to claim 5, wherein the force which is applied at the point of contact between the nose of the latch and the nose of the trip lever is directed towards the pin on which the trip lever is pivotally mounted and wherein the distance between the point of engagement and the pivotal axis of the latch is equal at the maximum to the distance between the said axis and the point at which the reaction is applied between the actuating pin and the retaining heel.