CN201690222U

CN201690222U - Time-delay overload short-circuit protector

Info

Publication number: CN201690222U
Application number: CN2010201822566U
Authority: CN
Inventors: 卜春国
Original assignee: 卜春国
Current assignee: Xiangyang Chongya Electrical Appliance Co., Ltd.
Priority date: 2010-04-27
Filing date: 2010-04-27
Publication date: 2010-12-29
Anticipated expiration: 2020-04-27

Abstract

A time-delay overload short-circuit protector is used for controlling electrical equipment, and is characterized in that an incoming contact is connected with three-phase alternating current, an outgoing contact is connected with a three-phase alternating current motor, an overtemperature protection switch is mounted on a mercury switch, the incoming contact is connected with the outgoing contact of the mercury switch through windings and conductive liquid, the incoming contact is connected with an electromagnet through a connecting terminal of the protection switch, and the turning arm of the mercury switch is hinged with an expansion link through a connecting rod. When the three-phase alternating current is connected with the incoming contact, under the ordinary temperature state, the overtemperature protection switch is turned on, the electromagnet is powered on, the mercury is connected with the incoming contact and the outgoing contact, and the mercury switch is turned on; when the load short circuits, the winding of the overtemperature protection switch generates heat, the power supply of the electromagnet is disconnected, under the action of a spring, the connecting rod is driven by the expansion link to move downwards, the mercury switch rotates anticlockwise around the axial line, the mercury is disengaged from the contacts, and the power supply is disconnected. The utility model can realize the short-circuit time-delay protection to a motor, has the advantages of simple structure, stability and reliability, no oxidation of the contacts, long service life and low cost, and is suitable for various occasions.

Description

The time-delay overload and short-circuit protector

Technical field

The utility model relates to a kind of overload and short-circuit protector in the electric equipment control field, especially for the electromechanical integration overload and short-circuit protector of protection motor.

Background technology

Short-circuit protector commonly used does not have delay function, when running into power-supply fluctuation, and often misoperation, when this short-circuit protector was used on the heavy-duty motor, the instantaneous overload of motor also can cause its misoperation.Another kind of intelligence time-delay short-circuit protector can be provided with guard time and overload power, but this protector complicated operation, the cost height, and fragile, be not suitable for being installed in outdoor.

Summary of the invention

For solving the motor damage that the motor short circuit causes; problems such as the machine operation instability that the instantaneous overload of motor causes; goal of the invention of the present utility model is to provide a kind of time-delay overload and short-circuit protector; cost is low; the reliability height can be realized the purpose that can ensure under various environment that motor safety moves.

For achieving the above object; the technical solution of the utility model is: inlet wire contact and three-phase alternating current are connected; the outlet contact connects three phase alternating current motor; protection switch is housed on the mercoid switch; protection switch is the overtemperature prote switch; the inlet wire contact is through the outlet contacting of winding by conductive liquid and mercoid switch; the inlet wire contact links to each other with electromagnet with the binding post of lead by protection switch respectively; the pivoted arm of mercoid switch is hinged by connecting rod and expansion link; mercoid switch is fixed in the casing by support, and electromagnet is fixed in the casing.

The bottom of the rotatable shell of described mercoid switch has the cavity that conductive liquid is housed, enclosure axis is inserted outlet contact and inlet wire contact respectively to two ends, one end of outlet contact and inlet wire contact is respectively charged in the cavity, shell is supported on the support by axle sleeve, be fixed with pivoted arm on the shell, conductive liquid in the cavity of mercoid switch is a mercury, and pressure-reducing valve is equipped with on the top of shell, and the shell of mercoid switch is interior, insulating oil is arranged at conductive liquid top.

When three-phase alternating current and inlet wire contacting, under the normal temperature state, the overtemperature prote switch conduction; the electromagnet energising, mercoid switch is under nature, and mercury is in the bottom of switch; mercury is connected inlet wire contact and outlet contact, mercoid switch conducting, three-phase alternating-current supply conducting.When short circuit appears in load, the winding of overtemperature prote switch begins heating, reach the upper limit of its design temperature when the temperature of overtemperature prote switch, the overtemperature prote switch disconnects electromagnet power supply, and under the active force of spring, the pull bar on the electromagnet moves down, drivening rod moves down, mercoid switch rotates counterclockwise around axis, and mercury breaks away from the contact, and power supply disconnects; When instantaneous overload appears in motor, winding gives the underheat of overtemperature prote switch to reach the upper limit of its design temperature, and the overtemperature prote switch can not disconnect, and has avoided misoperation; When short circuit appears in motor, winding heating overtemperature prote switch, temperature reaches its design temperature upper limit; the overtemperature prote switch disconnects, the electromagnet outage, and mercoid switch disconnects; three-phase alternating-current supply disconnects, and winding heating time is exactly the time of delaying time after the short circuit, can realize short circuit delay protection function.

The utility model is compared with existing short-circuit protector, can realize motor short circuit delay protection, and structure is simpler, and is reliable and stable, the contact non-oxidation, and long service life, with low cost, applicable to various occasions.

Description of drawings

Fig. 1 is a three-dimensional sketch of the present utility model;

Fig. 2 is the A-A profile of Fig. 1;

Fig. 3 is an electric sketch of the present utility model.

Embodiment

As Fig. 1; shown in Figure 2; inlet wire contact 7 is connected with three-phase alternating current; outlet contact 9 connects three phase alternating current motor; three mercoid switches 3 are installed in the casing 1 side by side by support 11; the pivoted arm 12 of mercoid switch 3 is hinged by E type connecting rod 2 and expansion link 13; overtemperature prote switch 5 is housed on the mercoid switch 3; inlet wire contact 7 is connected by the mercury conductive liquid 16 and the outlet contact 9 of mercoid switch 3 through winding 14; inlet wire contact 7 links to each other with electromagnet 10 with 8 with the binding post 4 of lead by protection switch 5 respectively, and the support 11 and the electromagnet 10 of mercoid switch are fixed in the shell 1.

Rotatable shell 15 bottom cavities 17 of mercoid switch 3 are equipped with conductive liquid 16, one end of outlet contact 9 and inlet wire contact 7 is respectively charged in the cavity 17, conductive liquid 16 in the cavity 17 is a mercury, insulating oil 19 is arranged at conductive liquid 16 tops, both protected the cleaning in the mercoid switch 3, can prevent that again mercury from evaporateing into contaminated air in the air, can play the effect of cooling simultaneously; Overtemperature prote switch 5 is embedded in the shell 15, and shell 15 is supported on the support 11 by axle sleeve 18, is fixed with pivoted arm 12 on the shell 15, and pressure-reducing valve 6 is equipped with on the top of the shell 15 of mercoid switch 3.

When three-phase alternating current was connected inlet wire contact 7, at normal temperatures, overtemperature prote switch 5 was in conducting state, electromagnet 10 energisings, and under initial position, the mercury in the mercoid switch 3 is connected inlet wire contact 7 and outlet contact 9, mercoid switch 3 conductings; When load outlet short circuit of receiving outlet contact 9 or overload; winding 14 through overtemperature prote switch 5 can generate heat; when temperature surpassed the upper limit set value of overtemperature prote switch 5, overtemperature prote switch 5 disconnected, electromagnet 10 outages; under the effect of spring tension; expansion link 13 on the electromagnet 10 moves down, and drives E type connecting rod 2 and moves down, and mercoid switch 3 rotates counterclockwise around axis; mercury 16 breaks away from the contact, and power supply disconnects.Because from the load short circuits heating in winding, to the outage of overtemperature prote switch, need a period of time, this switch has just possessed the function of delay protection like this.

As shown in Figure 3; JP1 is inlet wire contact 7; connect three-phase alternating current; wherein two-phase is connected with electromagnet 10 with 8 by the binding post 4 of JP2, JP3 overtemperature prote switch 5 respectively; inlet wire contact 7 is connected through winding 14 and outlet contact 9, and three-phase alternating current arrives outlet contact 9 after sequence number is 3 mercoid switch SW1, SW2, SW3.When at least one phase line short circuit of load, winding 14 heatings of overtemperature prote switch 5 seal in two at least one disconnections of switch of electromagnet 10, electromagnet 10 outages, and mercoid switch 3 is turned off, and three-phase alternating current is disconnected, and has so just played the effect of short-circuit protection.

Claims

One kind the time-delay overload and short-circuit protector; inlet wire contact (7) is connected with three-phase alternating current; outlet contact (9) connects three phase alternating current motor; it is characterized in that: protection switch (5) is housed on the mercoid switch (3); inlet wire contact (7) is connected by the conductive liquid (16) and the outlet contact (9) of mercoid switch (3) through winding (14); inlet wire contact (7) links to each other with electromagnet (10) with binding post (4), (8) of lead by protection switch (5) respectively, and the pivoted arm (12) of mercoid switch (3) is hinged by connecting rod (2) and expansion link (13).
2. time-delay overload and short-circuit protector according to claim 1; it is characterized in that: the bottom of the rotatable shell (15) of described mercoid switch (3) has the cavity (17) that conductive liquid (16) are housed; shell (15) axially two ends inserts inlet wire contact (7) and outlet contact (9) respectively and packs in the cavity (17); shell (15) is supported on the support (11) by axle sleeve (18), is fixed with pivoted arm (12) on the shell (15).
3. time-delay overload and short-circuit protector according to claim 2 is characterized in that: the conductive liquid (16) in the cavity (17) of mercoid switch (3) is a mercury.
4. time-delay overload and short-circuit protector according to claim 1 is characterized in that: pressure-reducing valve (6) is equipped with on the top of the shell (15) of mercoid switch (3).
5. time-delay overload and short-circuit protector according to claim 1 is characterized in that: protection switch (5) is the overtemperature prote switch.
6. time-delay overload and short-circuit protector according to claim 1 is characterized in that: the shell (15) of mercoid switch (3) is interior, insulating oil (19) is arranged at conductive liquid (16) top.
7. time-delay overload and short-circuit protector according to claim 1 is characterized in that: mercoid switch (3) is fixed in the casing (1) by support (11), and electromagnet (10) is fixed in the casing (1).