CN201233853Y

CN201233853Y - Contact device for plastic case circuit breaker

Info

Publication number: CN201233853Y
Application number: CNU2008201505677U
Authority: CN
Inventors: 丁一先; 全嘉青
Original assignee: PEOPLE'S ELECTRICAL APPLIANCE FACTORY SHANGHAI ELECTRICAL APPLIANCE CO Ltd
Current assignee: PEOPLE'S ELECTRICAL APPLIANCE FACTORY SHANGHAI ELECTRICAL APPLIANCE CO Ltd
Priority date: 2008-07-07
Filing date: 2008-07-07
Publication date: 2009-05-06
Anticipated expiration: 2018-07-07

Abstract

The utility model discloses a contact device of a molded case circuit breaker, which comprises a base with a fixed contact mounted on the upper surface thereof, and a rotating shaft which is mounted on a casing and can rotate around a shaft. A pivot pin is arranged on the rotating shaft; the pivot pin passes through a hole on a contact lever, so as to ensure that the contact lever can swing around the pivot pin and rotate together with the rotating shaft; a movable contact which can be in contact with and separated from the fixed contact is arranged on the contact lever; a spring mounting pin is arranged on the rotating shaft; a spring driven pin is mounted on the contact lever; one end of a contact spring sleeves the spring mounting pin, while the other end thereof sleeves the spring driven pin; a baffle block is arranged on the rotating shaft, and the lower surface of the baffle block is arc-shaped; the baffle block corresponds to a protuberance on the contact lever; and the protuberance on the contact lever is positioned on the contact lever, one end of the protuberance is connected with the smooth surface of the contact lever, while the other end thereof is connected with the upper notch of the contact lever. The utility model improves based on the prior circuit breaker, has the advantages of simple structure and convenient operation, and can perform the locking function.

Description

The contact device of breaker of plastic casing

Technical field

The utility model relates to a kind of breaker of plastic casing, relates in particular to the contact device of breaker of plastic casing.

Background technology

Breaker of plastic casing is that a kind of being used for controlled and protective device low-voltage distribution system or motor operation, in make-and-break contact, prevents the fault overcurrent phenomenon that reasons such as appearance as overload or short circuit cause in the circuit.When breaking down overcurrent, when satisfying certain disconnection condition that sets in advance, the contact device of breaker of plastic casing will be opened automatically, cuts off circuit, in order to avoid fault enlarges.

At present, along with the quick growth of power consumption equipment capacity, the fault current that requires breaker of plastic casing to disconnect also improves constantly, and therefore, being suitable for cutting off greatly on circuit breaker, the contact device of short circuit current constantly occurs.

The middle of last century, people have introduced the electrodynamic repulsion force principle, promptly utilize short circuit current with Huo Mu (Holm) power of fixing two contacts generations the contact device of circuit breaker just to be disconnected before electric current reaches maximum rapidly, thereby limited the expansion of short circuit current movable.The current limiting technique that people know in Here it is this area.

When producing big short circuit current in the circuit, making one of parts that circuit breaker can reliably disconnect fast is contact lever in the contact device, and moving contact is connected on the contact lever.The pressure that is subjected to when contact lever is scolded out is pre-set, has only when surpassing a predetermined value through the electric current of breaker contact point, under the situation of the pressure that the Huo Mu in the galvanic circle (Holm) power is subjected to greater than contact lever, just understands scold contact lever and holds.

The aforementioned pressure of mentioning is provided by touch spring usually.

After contact lever is scolded out, sealed in the bigger electric arc of resistance in the circuit, caused short circuit current to descend, Huo Muli reduces, and contact lever is replied again in the effect of touch spring pressure.If this moment, the mechanism of circuit breaker did not thread off as yet, the contact might reclose, and short circuit current might rise once more.

Usually, circuit breaker exists the danger that contact lever is replied, and this danger has hindered the ability that circuit breaker significantly improves cutting-off of short-circuit electric current.Then got rid of possibility that short circuit current once more rise if the contact lever that has a device to block to scold out makes it and can not reply this moment.

Conventional device is with touch spring and some other parts, use altogether such as keying, contact lever is remained on scold open position, to form a blocking mechanism, but need some more complicated parts to realize blocking function, have in addition adopt a device to realize blocking function specially.

The utility model content

The purpose of this utility model is to provide a kind of contact device of breaker of plastic casing, and this device improves on the basis of existing circuit breaker, and it is simple in structure, can realize blocking function.

The utility model is achieved in that a kind of contact device of breaker of plastic casing, comprising: the pedestal that fixed contact is installed above; One is installed in the rotating shaft that can sway on the shell, rotating shaft is provided with pivot pin, pivot pin passes the hole on the contact lever, makes contact lever the moving contact that can contact and separate with fixed contact be arranged on the contact lever around the pivot pin swing and along with rotating shaft is rotated together; Rotating shaft is provided with the spring mount pin, and the spring mount pin is parallel and depart from the center of rotation of rotating shaft, and spring follower pin is installed on the contact lever, and spring follower pin is parallel and depart from the contact lever pivot pin; Two touch springs that symmetric arrangement is arranged in the rotating shaft, touch spring one end are enclosed within on the described spring mount pin, and the other end is enclosed within on the described spring follower pin; It is characterized in that: a block is set in the described rotating shaft, and the lower surface of block is an arc, protruding corresponding on block and the contact lever, and the projection on the contact lever is positioned on the contact lever, and a protruding end connects the contact lever shiny surface, and the other end connects the upper notch of contact lever.

The diameter in the contact lever hole that described contact lever cooperates with pivot pin is much larger than the diameter of pivot pin, so just allow the center of the center of rotation pivot axis pin of contact lever when swing, thereby make the link stopper in the rotating shaft can under the effect of touch spring power, block or discharge contact lever.

There is a central slot along circumference at the middle part of described pivot pin, and this groove guarantees that contact lever is positioned at the central authorities of rotating shaft when the whole rotating assembly of assembling.

The utility model by increase in the rotating shaft block with contact lever on protruding corresponding, position relation by block in projection on the contact lever and the rotating shaft, realize that contact lever in the circuit breaker remains on and scold open position, make it and to reply, to form blocking mechanism.The utility model is processed into diameter much larger than pivot pin with the diameter in contact lever hole, so just allow the center of the center of rotation pivot axis pin of contact lever when swing, thereby make the link stopper in the rotating shaft can under the effect of touch spring power, block or discharge contact lever.The utility model compared with prior art, it is simple in structure, and is easy to operate, can realize blocking function.

Description of drawings

The utility model is described in further detail below in conjunction with the drawings and specific embodiments.

Fig. 1 contains the profile of a breaker of plastic casing of the present utility model when make position;

Fig. 2 is the profile of breaker of plastic casing shown in Figure 1 at open position;

Fig. 3 is scolding the profile of open position for breaker of plastic casing shown in Figure 1;

Fig. 4 is the profile of contact lever in make position;

Fig. 5 is the profile of contact lever at open position;

Fig. 6 is scolding the profile of open position for contact lever;

Fig. 7 is the structural representation of rotating assembly;

Fig. 8 is the structural representation that the contact lever hole cooperates with pivot pin.

Among the figure: 12 moving contacts, 13 fixed contacts, 14 contact levers, 15 rotating shafts, 16 pivot pins, 17 spring follower pins, 18 springs are installed lock, 19 touch springs, 20 contact lever holes, 21 blocks, 22 projectioies, 23 grooves, 24 upper notch, 101 shells, 102 handles, 103 contact devices, 104 arc-control devices, 105 pedestals.

Embodiment

Referring to Fig. 1, a kind of breaker of plastic casing is in case detect fault overcurrent with regard to interrupt circuit.The internal part of breaker of plastic casing is by shell 101 protections.There is a handle 102 to stretch out from a slit, handles switching on and off of breaker of plastic casing contact with the operating mechanism that is connected in handle 102 and contact device 103 through shell 101.

In the front of contact device 103 arc-control device 104 is arranged, referring to the top of Fig. 1.As known in the field, the effect of arc-control device 104 is cutting and the electric arc that produces when absorbing because of moving contact 12 with fixed contact 13 disjunction short circuit currents.Fixed contact 13 is installed on the pedestal 105.

Contact device 103 is positioned at the middle body of circuit breaker, as Fig. 1, Fig. 2 and shown in Figure 3.For multipole circuit breaker, each utmost point comprises a contact lever 14, and for example, three-pole breaker comprises three contact levers.Moving contact 12 usefulness welding manners are fixed on the end of contact lever 14.Rotating shaft 15 is installed on the shell 101 and can sways, and rotating shaft 15 is provided with pivot pin 16, and pivot pin 16 passes the contact lever hole 20 on the contact lever 14, makes the contact lever 14 can be around pivot pin 16 swing and along with rotating shaft 15 is rotated together.Contact lever hole 20 can allow contact lever pivot pin 16 to inject in the contact lever hole 20, the diameter in contact lever hole 20 is much larger than the diameter of pivot pin 16, so just allow the center of the oscillation center pivot axis pin 16 of contact lever 14, in addition, columniform pivot pin 16 has a central recess along circumference, be the diameter of the diameter of central recess less than pivot pin, this groove guarantees that contact lever 14 is positioned at the central authorities of rotating shaft 15 when assembling, referring to Fig. 8.And the length of pivot pin 16 enough cooperates with the width of rotating shaft 15, referring to Fig. 7.Because 19 applied pressures of a pair of touch spring, pivot pin 16 can not drop out when rotating shaft 15 swings.

Rotating shaft 15 is plastic insulation spares, and carries out at least two functions.At first, contact lever 14 is installed in implementation structure function in the rotating shaft 15, and contact lever 14 can be around pivot pin 16 swings and along with rotating shaft 15 is rotated together; Groove 23 in rotating shaft 15 1 sides allows contact lever 14 opening, disconnect, scolding between the open position and swing.Secondly, if circuit breaker more than a phase time, the unit that rotating shaft 15 can being made of one, rotating shaft 15 is connected also synchronization action with contact lever 14 with another contact lever 14.For example, if circuit breaker is three utmost points, rotating shaft 15 is the plastic insulation spares that three syndetons that similarly are parallel to each other are arranged so.

Touch spring 19 is the extension springs that can carry out several functions.Touch spring 19 is carried out two major functions, and it is both as contact pressure spring, again when scolding open position as the locking device of contact lever 14.Referring to Fig. 7.

One end of touch spring 19 is enclosed within on the spring mount pin 18 of rotating shaft 15, and the other end is enclosed within on the spring follower pin 17 on the contact lever 14.Under the effect of spring force, the contact lever 14 that has movable contact 12 is installed in the rotating shaft 15 to be swung around pivot pin 16, and when being in combined floodgate, disconnecting or scolding out different conditions at circuit breaker, contact lever 14 is in diverse location, referring to Fig. 4, Fig. 5, Fig. 6.

When circuit breaker disconnected, contact lever 14 was under the effect of touch spring 19 power, and upper notch 24 props up spring mount pin 18, contact lever 14 was positioned in the rotating shaft 15 and can landing, referring to Fig. 5; During breaker closing, the movable contact 12 of contact lever 14 front ends contacts with fixed contact 13, and touch spring 19 provides suitable contact pressure.

Circuit breaker runs into short circuit current, moving contact 12 is pushed away fixed contact 13 under electrodynamic effect, when promptly scolding exploitation to give birth to, contact lever 14 is that fulcrum is rotated counterclockwise with pivot pin 16, as long as the power of scolding out is enough big, projection 22 on the contact lever 14 will slip over the link stopper 21 in the rotating shaft 15, referring to Fig. 4, Fig. 6.Because the lower surface of block 21 is arcs, block 21 is corresponding with the projection 22 on the contact lever 14, and projection 22 1 ends on the contact lever 14 connect contact lever 14 shiny surfaces, and the other end connects the upper notch 24 of contact lever 14.Along with the decline of short circuit current, the electric power of pushing movable contact 12 open also reduces thereupon, but contact lever 14 when being pushed to scold open position by electric power the pulling force of touch spring increase.When electric power that the pulling force of touch spring 19 is subjected to greater than moving contact 12, contact lever 14 will with pivot pin 16 be fulcrum clockwise toward revolution since the link stopper 21 in the rotating shaft 15 stop that contact lever 14 will be locked in scolds open position.Referring to Fig. 6.

Contact lever 14 is returned to entopic action will disconnect the back generation at circuit breaker.When circuit breaker disconnects, the upper end of

contact lever

14 and 105 collisions of circuit breaker pedestal, referring to the place, the left side of Fig. 2, the thrust that collision produces will make contact lever 14 clockwise rotate around pivot pin 16, projection 22 on the contact lever 14 slips over the link stopper 21 of rotating shaft 15, and moving contact 12 is got back to normal off position.Referring to Fig. 5.

Claims

1, a kind of contact device of breaker of plastic casing comprises:

The pedestal of fixed contact is installed above one;

One is installed in the rotating shaft that can sway on the shell, rotating shaft is provided with pivot pin, pivot pin passes the hole on the contact lever, makes contact lever the moving contact that can contact and separate with fixed contact be arranged on the contact lever around the pivot pin swing and along with rotating shaft is rotated together;

Rotating shaft is provided with the spring mount pin, and the spring mount pin is parallel and depart from the center of rotation of rotating shaft, and spring follower pin is installed on the contact lever, and spring follower pin is parallel and depart from the contact lever pivot pin; Two touch springs that symmetric arrangement is arranged in the rotating shaft, touch spring one end are enclosed within on the described spring mount pin, and the other end is enclosed within on the described spring follower pin;

It is characterized in that:

A block is set in the described rotating shaft, and the lower surface of block is an arc, protruding corresponding on block and the contact lever, and the projection on the contact lever is positioned on the contact lever, and a protruding end connects the contact lever shiny surface, and the other end connects the upper notch of contact lever.

2, the contact device of breaker of plastic casing as claimed in claim 1 is characterized in that: the diameter in the contact lever hole that described contact lever cooperates with pivot pin is much larger than the diameter of pivot pin.

3, the contact device of breaker of plastic casing as claimed in claim 1 or 2 is characterized in that: there is a central slot along circumference at the middle part of described pivot pin.