CN2622819Y

CN2622819Y - Regulatable thermistor

Info

Publication number: CN2622819Y
Application number: CN 02290367
Authority: CN
Inventors: 余龙海; 高毅; 金祖勇; 吴修君
Original assignee: XIANGFAN DALI INDUSTRIAL CONTROL Co Ltd
Current assignee: Xiangfan Big Pawer Electrical Engineering Co., Ltd.
Priority date: 2002-12-10
Filing date: 2002-12-10
Publication date: 2004-06-30
Anticipated expiration: 2012-12-10

Abstract

The utility model is named a regulatable thermistor relating to an automatic regulatable thermistor for a reduced voltage starting of a large and medium-sized high-voltage motor. The utility model comprises a dynamic plate and a static plate which are fixed in an electrohydraulic tank. The static plate is fixed in the bottom of the electrohydraulic tank. The dynamic plate is arranged on an insulating screw mandrel through a lifting nut in the central of the dynamic plate. The insulating screw mandrel is arranged in the electrohydraulic tank vertically. The upper end of the insulating screw mandrel is fixed on the upper cover plate of the electrohydraulic tank and the lower end of the insulating screw mandrel is fixed on an insulating support of the electrohydraulic tank through upper and lower shaft sleeves respectively. A guide mechanism is arranged on the dynamic plate. The insulating support is fixed in the electrohydraulic tank. The utility model can achieve a soft start in constant current and adjust appropriately according to requirements. The utility model is small in size, reliable in operation, high in safety and stable in starting performance.

Description

Adjustable thermistor

Technical field

The utility model relates to the adjustable thermistor of the big-and-middle-sized alternating current motor reduced voltage starting of a kind of high pressure.

Background technology

At present, the known liquid resistor that is used for the big-and-middle-sized alternating current motor reduced voltage starting of high pressure has two kinds: a kind of is fixed thermistor, and a kind of is adjustable liquid resistance device.These two kinds of start modes all are better than traditional reactor reduced voltage starting and auto-transformer starting, it is little and constant to have starting current, power factor height during starting, little during starting to the impact of electrical network and plant equipment, working service is convenient, the cost performance advantages of higher, but have following shortcoming: concerning fixed liquid resistor: 1, environmental suitability is relatively poor.Because resistor fluid is the conducting liquid with negative temperature characteristic, be subjected to the influence of variation of ambient temperature bigger, because temperature is low, so resistance value is bigger, starting current diminishes, thereby makes the electric motor starting time lengthening in the winter time; And summer temp is higher, and resistance is less, and it is big that starting current becomes, and the starting time shortens, and these starting performance that change motor all have certain influence.Electricity liquid heating up during 2, owing to starting, the resistor fluid change in resistance is bigger, thereby the performance of starting next time is produced certain influence; The unsteadiness that these all can cause the starting equipment performance also causes starting process to monitor, thereby influences starting effect.Existing adjustable liquid resistance starter, though resistance value is adjustable, but still there is following shortcoming: 1, because the same transmission mechanism of transmission of three-phase electrode, this transmission mechanism all is contained in the top of electrohydraulic box, take very big space, makes the casing volume become very big, 2, the movable plate electrode of three-phase electrode needs interlock, make the installation of movable plate electrode be difficult to compact the installation, therefore vibration is bigger when work, has accident potential; 3, in the process that movable plate electrode moves in electrohydraulic box, take electric liquid out of electrohydraulic box easily, influence security performance; 4, omnidistance adjustable between movable plate electrode and the static plate electrode, when two battery lead plates distance was very little, heating liquid reduced in a large number, and the conductive liquid local boiling is boiled, and very big potential safety hazard is arranged.

Summary of the invention

It is adjustable that the purpose of this utility model is exactly a kind of resistance value that provides at above weak point, automatically adaptive temperature change and can compensate automatically, volume is little, but reliable, safe, the more reasonable constant current soft start of design, cost performance is higher, starting performance is very stable adjustable thermistor.

The technical scheme that realizes the utility model purpose is: the resistor fluid that is filled with negative temperature coefficient in electrohydraulic box, moving, static plate electrode whole process is operated in the resistor fluid, static plate electrode is horizontally fixed on the bottom of electrohydraulic box, movable plate electrode is fixed on the insulation screw mandrel that vertically is installed in the electrohydraulic box by lifting nut, on having on the movable plate electrode, the down stroke guiding mechanism, movable plate electrode can move up and down along insulation screw mandrel and guiding mechanism in horizontal direction, the upper end of insulation screw mandrel is fixed on the upper cover plate of electrohydraulic box by Upper shaft sleeve, the insulation screw mandrel stretches out on the termination of upper cover plate and is fixed with the shaft coupling that links with transmission mechanism, and the lower end of insulation screw mandrel is supported by the insulation that Lower shaft sleeve is fixed in the electrohydraulic box; The insulation screw mandrel is can forward and reverse rotation in upper and lower axle sleeve under the effect of transmission mechanism, thereby adjusts the upper-lower position of movable plate electrode, promptly changes the resistance value between the two-plate; Insulation is supported and fixed on the inside of electrohydraulic box, makes to have certain minimum range between movable plate electrode and the static plate electrode.

The upper and lower stroke guiding mechanism of adorning on the said movable plate electrode in the technique scheme is the static plate electrode electrode, and this electrode is the contact rod that is set with insulating sleeve, is upward through the pilot hole of movable plate electrode, and stretches out the electrohydraulic box cover plate.

The utility model is compared with prior art, because the three-phase variable resistor is respectively by transmission mechanism control (every phase one sets of transmission mechanism), therefore reduced volume, avoided the vibration in the work, made reliable, work safety, movable plate electrode is to move up and down on the insulation screw mandrel, has avoided resistor fluid excessive, keeps certain spacing between the sound pole plate, avoid the fluid temperature between the sound pole plate too high, increased fail safe.And can realize intelligent control, detect automatically, regulate automatically and realize the constant current soft start according to motor starting parameters; Guarantee one push start success and can start continuously three times that performance is more stable when making starting, equipment is more reliable.

Description of drawings

Accompanying drawing is a structural representation of the present utility model.

Embodiment

The utility model is described in further detail below in conjunction with accompanying drawing.

Electrohydraulic box (1) is made by insulating material, be filled with resistor fluid (12) in the electrohydraulic box (1) with negative temperature coefficient, level is provided with upper and lower pole plate in electrohydraulic box (1), be dynamic and static pole plate (5,8), static plate electrode (8) is horizontally fixed on the bottom of electrohydraulic box, the electrode (2) of static plate electrode (8) is for being equipped with the copper rod of insulating sleeve (3), be upward through the pilot hole of movable plate electrode (5), draw from the cover plate of electrohydraulic box (1), this electrode (2) also can be used as the guiding mechanism of the upper and lower stroke of movable plate electrode (5); Insulation screw mandrel (10) is vertically fixed in the electrohydraulic box (1); The upper end of insulation screw mandrel (10) is fixed on electrohydraulic box (1) upper cover plate by Upper shaft sleeve (11), dynamic and static pole plate (5,8) and insulation screw mandrel (10) all are immersed in the resistor fluid (12), insulation screw mandrel (10) stretches out on the termination of electrohydraulic box (1) upper cover plate and is fixed with shaft coupling (13), is convenient to connect with transmission mechanism; The lower end of insulation screw mandrel (10) is fixed on insulation by Lower shaft sleeve (7) and supports in the centre bore on (6), and the screw mandrel (10) that insulate can rotate in upper and lower axle sleeve (11,7); On movable plate electrode (5) centre bore lifting nut (9) is housed, the electrode (4) of movable plate electrode (5) is a flexible cable, draws from electrohydraulic box (1) upper cover plate; Lifting nut (9) is sleeved on the insulation screw mandrel (10), when rotating under the drive of insulation screw mandrel (10) at transmission mechanism, movable plate electrode (5) is moved along insulation screw mandrel (10) is upper and lower, thereby reach the distance of regulating between the dynamic and static pole plate (5,8), the i.e. resistance of liquid resistance; Insulation is supported (6) and is fixed between the dynamic and static pole plate (5,8), the inside of electrohydraulic box (1), and and static plate electrode (8) between certain distance is arranged keep a determining deviation so that make between the sound pole plate (5,8), avoid between the dynamic and static pole plate (5,8) electric liquid temp too high; What provide among the figure is the structural representation of single-phase adjustable resistance, when being used for the starting of three-phase large ac machines, three resistors of the present utility model is connected to respectively in the three-phase winding of motor, can control respectively.

Claims

1. adjustable thermistor that is used for high pressure large and medium motor reduced voltage starting, comprise the electrohydraulic box (1) that is filled with resistance liquid (12), dynamic and static pole plate (5,8), it is characterized in that: vertical fixing has insulation screw mandrel (10) in electrohydraulic box (1), the upper end of insulation screw mandrel (10) is fixed on the cover plate of electrohydraulic box (1) by Upper shaft sleeve (11), the lower end of insulation screw mandrel (10) is fixed on insulation by Lower shaft sleeve (7) and supports on (6), and the inside that (6) are fixed on electrohydraulic box (1) is supported in insulation; Movable plate electrode (5) is by being fixed therein lifting nut (9) horizontal set on the heart hole in insulation screw mandrel (10); Upper and lower stroke guiding mechanism is housed on movable plate electrode (5); Static plate electrode (8) is horizontally fixed on the bottom of electrohydraulic box (1).

2. adjustable thermistor as claimed in claim 1, the electrode (2) that the upper and lower stroke guiding mechanism that it is characterized in that the last dress of said movable plate electrode (5) is static plate electrode (8), electrode (2) is for being set with the contact rod of insulating sleeve (3), be upward through the pilot hole of movable plate electrode (5), and stretch out the upper cover plate of electrohydraulic box (1).