CN110653622A

CN110653622A - Refrigerant pipe brazing device for central air conditioner

Info

Publication number: CN110653622A
Application number: CN201910986382.2A
Authority: CN
Inventors: 刘燕青
Original assignee: Individual
Current assignee: Jiangsu Taiente Environmental Technology Co ltd
Priority date: 2019-10-17
Filing date: 2019-10-17
Publication date: 2020-01-07
Anticipated expiration: 2039-10-17
Also published as: CN110653622B

Abstract

The invention relates to a central air conditioner, in particular to a refrigerant pipe brazing device for the central air conditioner. The invention aims to provide a refrigerant pipe brazing device for a central air conditioner. A refrigerant pipe brazing device for a central air conditioner comprises a side supporting plate, a nitrogen supply mechanism, a weld opening polishing and grinding mechanism, a corner connecting pipe expanding mechanism and a weld opening feeding brazing mechanism; a control display screen is arranged in the middle of the left end of the side supporting plate; the bottom of the right end of the side supporting plate is connected with the bottom supporting table; the right side of the top end of the bottom support table is connected with a welding port polishing and grinding mechanism, and the left end of the welding port polishing and grinding mechanism is connected with a nitrogen supply mechanism; the right middle part of the top end of the bottom supporting table is connected with the corner connecting pipe expanding mechanism, and the effects of accurately and flatly cutting the refrigerant pipe, polishing and feeding without oxidation, controlling and spraying welding flux at a welding port and accurately expanding the pipe and welding in a matching manner are achieved.

Description

Refrigerant pipe brazing device for central air conditioner

Technical Field

The invention relates to a central air conditioner, in particular to a refrigerant pipe brazing device for the central air conditioner.

Background

The central air conditioning system is composed of one or more cold and heat source systems and a plurality of air conditioning systems, and the system is different from the traditional refrigerant type air conditioner, and the air is intensively treated (such as a single machine, VRV) to achieve the comfort requirement. The principle of liquid gasification refrigeration is adopted to provide the required cold energy for the air conditioning system so as to offset the heat load of the indoor environment; the heating system provides the required heat for the air conditioning system to offset the cold and warm load of the indoor environment, a cooling system is arranged in the heating system, one of important parts is a refrigerant pipeline which is made of copper pipes, the welding requirement is high, the precision is high, namely the problem of partial oxidation cannot occur in high-temperature welding is solved, but in the manual brazing welding process in the prior art, due to the fact that nitrogen power is insufficient, the pipeline cutting mode is mostly processed in an electric saw cutting mode, a weld crater is polished and brazed and fed, the weld crater is partially oxidized, in the manual welding process, a manual pipe expander cannot achieve accurate positioning of the weld crater, cutting notches of the refrigerant pipe are uneven, the welding area cannot be determined in the inner feeding process, the service life is reduced due to partial oxidation of refrigerant in the polishing process, and the feeding area on the inner side of the weld crater cannot be controlled, the limit of the pipe expander mouth can not be determined, and the welding is misplaced.

Disclosure of Invention

The invention aims to overcome the defects that in the manual brazing welding process in the prior art, due to the fact that nitrogen power is insufficient, a pipeline cutting mode is mostly processed in an electric saw cutting mode, a weld crater is polished and is partially oxidized in the brazing feeding process, and in the manual welding process, a manual pipe expander cannot realize accurate positioning of the weld crater, so that the cutting cuts of refrigerant pipes are uneven, the welding area cannot be determined in the inner side feeding process, the partial oxidation of the refrigerant pipe causes the reduction of the service life in the polishing process, the feeding area on the inner side of the weld crater cannot be controlled, the limit of an expanded pipe opening of the pipe expander cannot be determined, and welding is staggered.

The invention is achieved by the following specific technical means:

a refrigerant pipe brazing device for a central air conditioner comprises a side supporting plate, a control display screen, a bottom supporting table, a cutting and intercepting mechanism, a nitrogen supply mechanism, a weld crater polishing and grinding mechanism, a corner connecting pipe expanding mechanism and a weld crater feeding brazing mechanism; a control display screen is arranged in the middle of the left end of the side supporting plate; the bottom of the right end of the side supporting plate is connected with the bottom supporting table; the top of the right end of the side supporting plate is connected with a cutting and intercepting mechanism; the middle part of the right end of the side supporting plate is connected with a nitrogen supply mechanism, and the upper left part of the nitrogen supply mechanism is connected with a cutting and intercepting mechanism; the middle lower part of the right end of the side supporting plate is connected with a welding port feeding and brazing mechanism, and the top end of the welding port feeding and brazing mechanism is connected with a nitrogen supply mechanism; the bottom end of the welding port feeding and brazing mechanism is connected with the bottom support table; the right side of the top end of the bottom support table is connected with a welding port polishing and grinding mechanism, and the left end of the welding port polishing and grinding mechanism is connected with a nitrogen supply mechanism; the right middle part of the top end of the bottom supporting table is connected with the corner connecting pipe expanding mechanism.

Preferably, the cutting and intercepting mechanism comprises a motor, a first transmission wheel, a second transmission wheel, a third transmission wheel, a first flat gear, a fourth transmission wheel, a fifth transmission wheel, a second flat gear, a rotating fixed rod, a fixed pipe sleeve, a pipe clamp, a locking buckle, a sixth transmission wheel, a cutting fixed shaft seat, a rotating cutter, a rotating fixed bearing, a connecting slip ring, a first screw rod, a seventh transmission wheel and an eighteenth transmission wheel; the middle part of the right end of the motor is rotationally connected with the first driving wheel; the middle part of the right end of the first driving wheel is rotationally connected with the second driving wheel; the bottom end of the second driving wheel is in transmission connection with a third driving wheel through a belt; the middle part of the right end of the third driving wheel is rotationally connected with the first flat gear; the middle part of the right end of the first flat gear is rotationally connected with a fourth transmission wheel; the top end of the first flat gear is meshed with the second flat gear; the middle part of the right end of the fourth driving wheel is rotationally connected with the fifth driving wheel; the top end of the fourth transmission wheel is in transmission connection with the sixth transmission wheel through a belt; the middle upper part at the left end of the second flat gear is connected with the middle upper part; the inner middle part of the fifth driving wheel is in sliding connection with the rotating fixed rod; the right end of the fifth driving wheel is rotationally connected with the eighteenth driving wheel; the inner middle part of the second flat gear is rotationally connected with the fixed pipe sleeve; the left end of the fixed pipe sleeve is connected with the pipe clamp; the right end of the outer surface of the fixed pipe sleeve is sleeved with the locking buckle; the right end of the locking buckle is provided with a cutting fixing shaft seat; a rotary cutter is arranged at the bottom in the cutting fixed shaft seat, and the middle part of the left end of the rotary cutter is connected with a sixth driving wheel; the middle part of the right end of the rotary cutter is rotationally connected with the rotary fixed bearing; the right end of the rotary fixed bearing is connected with the connecting slip ring; the middle part of the bottom end of the connecting slip ring is rotationally connected with the first screw rod; the bottom end of the first screw rod is rotationally connected with a seventh transmission wheel; the left end of the motor is connected with the side supporting plate; the middle part of the left end of the third driving wheel is connected with the side supporting plate; the left end of the rotating fixed rod is connected with the side supporting plate; the middle part of the right end of the sixth driving wheel is connected with the side supporting plate; the bottom end of the fifth driving wheel is connected with a nitrogen supply mechanism; the left end of the seventh driving wheel is connected with a nitrogen supply mechanism; the bottom end of the eighteenth driving wheel is connected with the corner connecting pipe expanding mechanism.

Preferably, the nitrogen supply mechanism comprises a fixed bottom plate, a liquid nitrogen storage tank, a first nitrogen conveying pipe, a first air pump, a second nitrogen conveying pipe, an elastic pipe orifice, a buffer channel plate, a sliding plate, a first spring, a second spring, abrasive paper, a polishing wheel, a linkage rod, a magnetic fixed rod, a joint fixed plate, an electromagnet, a first bevel gear, a second bevel gear, an eighth transmission wheel and a connecting support plate; the left side of the top end of the fixed bottom plate is connected with a liquid nitrogen storage tank; the right side of the top end of the fixed bottom plate is connected with a first air pump; the top end of the liquid nitrogen storage tank is connected with a first nitrogen conveying pipe, and the right end of the first nitrogen conveying pipe is connected with a first air pump; the middle part of the right end of the first air pump is connected with a second nitrogen conveying pipe; a first bevel gear is arranged on the upper right of the top end of the first air pump; the right end of the second nitrogen conveying pipe is provided with an elastic pipe orifice; the right upper part of the elastic pipe orifice is connected with the buffer channel plate; the middle part of the front end of the elastic pipe orifice is connected with a linkage rod; the left end of the buffer channel plate is connected with the sliding plate; sand paper is arranged at the right end of the buffer channel plate; the left middle part of the bottom end of the sliding plate is connected with a first spring; the right middle part of the bottom end of the sliding plate is connected with a second spring; the outer side of the sand paper is connected with a grinding wheel; the right end of the linkage rod is connected with the magnetic fixed rod; the top end of the outer surface of the magnetic fixed rod is in sliding connection with the attaching fixed plate; an electromagnet is arranged below the bottom end of the magnetic fixed rod; the bottom end of the electromagnet is connected with the connecting support plate; the bottom of the right end of the first bevel gear is meshed with the second bevel gear; the middle part of the right end of the first bevel gear is rotationally connected with an eighth driving wheel; the left end of the outer surface of the first bevel gear is connected with a cutting and intercepting mechanism; the bottom of the left end of the liquid nitrogen storage tank is connected with a welded junction feeding and brazing mechanism; the bottom end of the outer surface of the second bevel gear is connected with a cutting and intercepting mechanism; the bottom end of the eighth driving wheel is connected with a welding port feeding and brazing mechanism; the bottom end of the connecting support plate is connected with the bottom support platform; the left side of the bottom end of the second nitrogen conveying pipe is connected with a welding port feeding and brazing mechanism.

Preferably, the weld crater polishing and grinding mechanism comprises a ninth driving wheel, a third bevel gear, a tenth driving wheel, a fourth bevel gear, an eleventh driving wheel, a cam, a spring rod, an in-pipe steel brush, a rotating clamping strip and an impact block; the middle part of the left end of the ninth driving wheel is rotationally connected with the third bevel gear; the rear end of the outer surface of the third bevel gear is in transmission connection with a tenth transmission wheel through a belt; the rear side of the left end of the third bevel gear is meshed with the fourth bevel gear; the middle part of the left end of the tenth driving wheel is rotationally connected with the spring rod; the rear end of the outer surface of the fourth bevel gear is in transmission connection with an eleventh transmission wheel through a belt; the middle part of the rear end of the eleventh transmission wheel is rotationally connected with the cam; the left end of the cam is in transmission connection with the impact block; the left end of the spring rod is rotationally connected with the steel brush in the pipe; the right side of the outer surface of the steel brush in the pipe is rotationally connected with the rotating clamping strip; the bottom end of the ninth driving wheel is connected with the corner connecting pipe expanding mechanism; the middle part of the right end of the tenth driving wheel is connected with a nitrogen supply mechanism; the middle part of the rear end of the eleventh driving wheel is connected with a nitrogen supply mechanism.

Preferably, the corner connecting pipe expanding mechanism comprises a table-shaped fixing seat, an edge limiting block, a right-angle refrigerant pipe, a special-shaped pipe expanding wheel, a helical gear, an electric telescopic rotating shaft, a twelfth driving wheel and a nineteenth driving wheel; the middle part of the bottom end in the table-type fixed seat is provided with an edge limiting block; the inner rear side of the platform-shaped fixed seat is connected with a right-angle refrigerant pipe; a special-shaped pipe expanding wheel is arranged at the right end of the right-angle refrigerant pipe; the right end of the special-shaped pipe expanding wheel is connected with the helical gear; the middle part of the right end of the helical gear is rotationally connected with the electric telescopic rotating shaft; the right end of the electric telescopic rotating shaft is rotationally connected with a twelfth driving wheel; the middle part of the right end of the twelfth driving wheel is rotationally connected with the nineteenth driving wheel; the top end of the nineteenth transmission wheel is connected with a weld crater polishing and grinding mechanism; the top end of the twelfth transmission wheel is connected with the cutting and intercepting mechanism; the bottom end of the table-shaped fixed seat is connected with the bottom supporting table.

Preferably, the crater feeding and soldering mechanism comprises a second air pump, a third nitrogen delivery pipe, a fourth nitrogen delivery pipe, a fuel storage tank, a fuel delivery pipe, a flame surrounding type spray welding device, a liquid solder storage tank, a solder delivery pipe, a solder spraying device, a fifth nitrogen delivery pipe, a bearing seat, a thirteenth transmission wheel, a fourteenth transmission wheel and a fifteenth transmission wheel; the right side of the top end of the second air pump is connected with a third nitrogen conveying pipe; the middle part of the right end of the second air pump is connected with a fourth nitrogen conveying pipe; a fuel storage tank is arranged at the rear right part of the third nitrogen delivery pipe; the right side of the top end of the fuel storage tank is connected with a fuel delivery pipe; the right end of the fuel delivery pipe is connected with the flame surrounding type spray welding device; a liquid solder storage tank is arranged above the top end of the flame surrounding type spray welding device; the bottom of the right end of the liquid solder storage tank is connected with a solder delivery pipe; the right end of the solder conveying pipe is connected with a solder spraying device; the middle part of the left end of the solder spraying device is connected with a fifth nitrogen conveying pipe; the right end of the solder spraying device is provided with a bearing seat; the right end of the bearing seat is rotationally connected with a thirteenth driving wheel; the middle part of the right end of the thirteenth driving wheel is rotationally connected with the fourteenth driving wheel; the bottom end of the thirteenth driving wheel is in transmission connection with the fifteenth driving wheel through a belt; the bottom end of the second air pump is connected with the bottom support platform; the bottom end of the fuel storage tank is connected with the bottom support platform; the top of the right end of the third nitrogen conveying pipe is connected with a nitrogen supply mechanism; the top end of the fifth nitrogen conveying pipe is connected with a nitrogen supply mechanism; the top end of the fourteenth driving wheel is connected with the nitrogen supply mechanism.

Preferably, the special-shaped pipe expanding wheel comprises an inner wheel, a second screw rod, a fifth bevel gear and an outer expanding ring; the left middle upper part of the inner wheel is rotationally connected with a second screw rod; the right lower part of the second screw rod is rotationally connected with a fifth bevel gear; the upper left part of the second screw rod is rotationally connected with the external expansion ring; the right end of the fifth bevel gear is connected with the bevel gear.

Preferably, the flame surrounding type spray welding device comprises a flame welding gun, a third flat gear, a fourth flat gear, a sixteenth driving wheel, a seventeenth driving wheel, a connecting synchronous bearing, an L-shaped fixed pipe, a rebound rod and a tail protection seat; a third spur gear is arranged on the lower right of the flame welding gun; the bottom end of the third flat gear is meshed with the fourth flat gear; the bottom of the right end of the third spur gear is connected with a connecting synchronous bearing; the middle part of the right end of the fourth flat gear is rotationally connected with a sixteenth driving wheel; the bottom end of the sixteenth driving wheel is in transmission connection with the seventeenth driving wheel through a belt; the inner side of the connecting synchronous bearing is connected with the L-shaped fixed pipe; the top of the front end of the L-shaped fixed pipe is connected with a rebound rod; the bottom end of the rebound rod is connected with the tail protection seat; the left end of the flame welding gun is connected with the fuel delivery pipe; the middle part of the right end of the seventeenth driving wheel is rotationally connected with the fifteenth driving wheel; the left middle part of the bottom end of the flame welding gun is connected with the bottom support platform; the bottom end of the connecting synchronous bearing is connected with the bottom supporting platform.

Preferably, the solder spraying device comprises a first solder spraying chamber, a nitrogen gas spray pipe, a second solder spraying chamber, a first clip-shaped solder spray pipe and a second clip-shaped solder spray pipe; the bottom end of the first solder spraying chamber is connected with the nitrogen spraying pipe; the middle lower part of the right end of the first solder spraying chamber is connected with the first clip-shaped solder spraying pipe; the bottom end of the nitrogen spray pipe is connected with the second solder spraying chamber; the right end of the second solder spraying chamber is connected with the second clip-shaped solder spraying pipe; the left ends of the first solder eruption chamber and the second solder eruption chamber are connected with a solder delivery pipe; the left end of the nitrogen spray pipe is connected with a fifth nitrogen conveying pipe.

Compared with the prior art, the invention has the following beneficial effects:

in order to solve the problems that the cutting cuts of the refrigerant pipe are not uniform during the brazing welding of the refrigerant pipe, the welding area can not be determined in the inner side feeding process, the service life is shortened due to partial oxidation of the refrigerant pipe in the polishing process, the limit of the pipe expanding opening of the pipe expander can not be determined, the feeding area on the inner side of the welding opening can not be controlled, and the welding is staggered in the prior art, a cutting and intercepting mechanism, a nitrogen supply mechanism, a welding opening polishing and grinding mechanism, a corner connecting pipe expanding mechanism and a welding opening feeding brazing mechanism are designed, when in use, a new pipe with smooth cuts is cut out through the cutting and intercepting mechanism, then the nitrogen supply mechanism is matched with the welding opening polishing and grinding mechanism to finish non-oxidation polishing and grinding, the welding opening expanding operation of a right-angle pipe is finished through the corner connecting pipe expanding mechanism, finally the brazing welding of the refrigerant pipe is finished through the welding opening feeding brazing mechanism, and, the material loading of polishing of non-oxidation can control spraying crater solder, and the effect of accurate expand pipe fit welding.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic view of the cutting and intercepting mechanism of the present invention;

FIG. 3 is a schematic view of the nitrogen gas supply mechanism according to the present invention;

FIG. 4 is a schematic structural view of a weld joint polishing and grinding mechanism according to the present invention;

FIG. 5 is a schematic structural view of a corner connecting pipe expanding mechanism of the present invention;

FIG. 6 is a schematic structural view of a fillet feeding and brazing mechanism of the present invention;

FIG. 7 is a schematic view of a special-shaped pipe expanding wheel according to the present invention;

FIG. 8 is a schematic structural view of a flame-looping type spray welding device of the present invention;

FIG. 9 is a schematic view of the solder-spraying apparatus of the present invention.

The labels in the figures are: 1-side supporting plate, 2-control display screen, 3-bottom supporting table, 4-cutting intercepting mechanism, 5-nitrogen supply mechanism, 6-weld joint polishing and grinding mechanism, 7-corner connecting pipe expanding mechanism, 8-weld joint feeding brazing mechanism, 401-motor, 402-first driving wheel, 403-second driving wheel, 404-third driving wheel, 405-first flat gear, 406-fourth driving wheel, 407-fifth driving wheel, 408-second flat gear, 409-rotating fixed rod, 4010-fixed pipe sleeve, 4011-pipe clamp, 4012-locking buckle, 4013-sixth driving wheel, 4014-cutting fixed shaft seat, 4015-rotating cutter, 4016-rotating fixed bearing, 4017-connecting sliding ring, 4018-first screw rod, 4019-seventh driving wheel, 4020-eighteenth driving wheel, 501-fixed base plate, 502-liquid nitrogen storage tank, 503-first nitrogen delivery pipe, 504-first air pump, 505-second nitrogen delivery pipe, 506-elastic nozzle, 507-buffer channel plate, 508-slide plate, 509-first spring, 5010-second spring, 5011-sand paper, 5012-grinding wheel, 5013-linkage rod, 5014-magnetic fixed rod, 5015-joint fixed plate, 5016-electromagnet, 5017-first bevel gear, 5018-second bevel gear, 5019-eighth driving wheel, 5020-connection support plate, 601-ninth driving wheel, 602-third bevel gear, 603-tenth driving wheel, 604-fourth bevel gear, 605-eleventh driving wheel, 606-cam, 607-spring rod, 608-steel brush in tube, 609-rotating clamping strip, 6010-impact block, 701-table type fixed seat, 702-edge limited block, 703-right angle refrigerant tube, 704-special-shaped tube expanding wheel, 705-helical gear, 706-electric telescopic rotating shaft, 707-twelfth driving wheel, 708-nineteenth driving wheel, 801-second air pump, 802-third nitrogen conveying pipe, 803-fourth nitrogen conveying pipe, 804-fuel storage tank, 805-fuel conveying pipe, 806-flame surrounding type spray welding device, 807-liquid solder storage tank, 808-solder conveying pipe, 809-spray welding device, 8010-fifth nitrogen conveying pipe, 8011-bearing seat, 8012-thirteenth driving wheel, 8013-fourteenth driving wheel, 8014-a fifteenth driving wheel, 70401-an inner wheel, 70402-a second screw, 70403-a fifth bevel gear, 70404-an outward expanding ring, 80601-a flame welding gun, 80602-a third spur gear, 80603-a fourth spur gear, 80604-a sixteenth driving wheel, 80605-a seventeenth driving wheel, 80606-a connecting synchronous bearing, 80607-an L-shaped fixed tube, 80608-a rebound rod, 80609-a tail protection seat, 80901-a first solder spraying chamber, 80902-a nitrogen gas spraying pipe, 80903-a second solder spraying chamber, 80904-a first clip solder spraying pipe and 80905-a second clip solder spraying pipe.

Detailed Description

The invention is further described below with reference to the figures and examples.

Examples

A refrigerant pipe brazing device for a central air conditioner is shown in figures 1-9 and comprises a side supporting plate 1, a control display screen 2, a bottom supporting table 3, a cutting and intercepting mechanism 4, a nitrogen supply mechanism 5, a weld opening polishing and grinding mechanism 6, a corner connecting pipe expanding mechanism 7 and a weld opening feeding brazing mechanism 8; a control display screen 2 is arranged in the middle of the left end of the side supporting plate 1; the bottom of the right end of the side supporting plate 1 is connected with a bottom supporting table 3; the top of the right end of the side supporting plate 1 is connected with a cutting and intercepting mechanism 4; the middle part of the right end of the side supporting plate 1 is connected with a nitrogen supply mechanism 5, and the upper left part of the nitrogen supply mechanism 5 is connected with a cutting and intercepting mechanism 4; the middle lower part of the right end of the side supporting plate 1 is connected with a welding port feeding brazing mechanism 8, and the top end of the welding port feeding brazing mechanism 8 is connected with a nitrogen supply mechanism 5; the bottom end of the welding port feeding and brazing mechanism 8 is connected with the bottom support table 3; the right side of the top end of the bottom supporting table 3 is connected with a welding port polishing and grinding mechanism 6, and the left end of the welding port polishing and grinding mechanism 6 is connected with a nitrogen supply mechanism 5; the right middle part of the top end of the bottom supporting table 3 is connected with a corner connecting pipe expanding mechanism 7.

The cutting and intercepting mechanism 4 comprises a motor 401, a first driving wheel 402, a second driving wheel 403, a third driving wheel 404, a first flat gear 405, a fourth driving wheel 406, a fifth driving wheel 407, a second flat gear 408, a rotary fixing rod 409, a fixing pipe sleeve 4010, a pipe clamp 4011, a locking buckle 4012, a sixth driving wheel 4013, a cutting fixing shaft seat 4014, a rotary cutter 4015, a rotary fixing bearing 4016, a connecting slip ring 4017, a first screw 4018, a seventh driving wheel 4019 and an eighteenth driving wheel 4020; the middle part of the right end of the motor 401 is rotatably connected with the first driving wheel 402; the middle part of the right end of the first driving wheel 402 is rotatably connected with a second driving wheel 403; the bottom end of the second driving wheel 403 is in transmission connection with a third driving wheel 404 through a belt; the middle part of the right end of the third driving wheel 404 is rotationally connected with a first flat gear 405; the middle part of the right end of the first flat gear 405 is rotationally connected with a fourth driving wheel 406; the top end of the first flat gear 405 is meshed with the second flat gear 408; the middle part of the right end of the fourth driving wheel 406 is rotationally connected with a fifth driving wheel 407; the top end of the fourth driving wheel 406 is in driving connection with a sixth driving wheel 4013 through a belt; the middle upper part of the left end of the second flat gear 408 is connected with; the inner middle part of the fifth transmission wheel 407 is in sliding connection with the rotating fixed rod 409; the right end of the fifth driving wheel 407 is rotatably connected with an eighteenth driving wheel 4020; the inner middle part of the second flat gear 408 is rotationally connected with the fixed pipe sleeve 4010; the left end of the fixed pipe sleeve 4010 is connected with a pipe clamp 4011; the right end of the outer surface of the fixed pipe sleeve 4010 is sleeved with a locking buckle 4012; the right end of the locking buckle 4012 is provided with a cutting fixed shaft seat 4014; a rotary cutter 4015 is arranged at the bottom in the cutting fixed shaft seat 4014, and the middle part of the left end of the rotary cutter 4015 is connected with a sixth driving wheel 4013; the middle part of the right end of the rotary cutter 4015 is rotatably connected with a rotary fixed bearing 4016; the right end of the rotary fixed bearing 4016 is connected with a connecting slip ring 4017; the middle part of the bottom end of the connecting slip ring 4017 is rotationally connected with a first screw rod 4018; the bottom end of the first screw rod 4018 is rotatably connected with a seventh driving wheel 4019; the left end of the motor 401 is connected with the side supporting plate 1; the middle part of the left end of the third driving wheel 404 is connected with the side supporting plate 1; the left end of the rotating fixing rod 409 is connected with the side supporting plate 1; the middle part of the right end of the sixth driving wheel 4013 is connected with the side supporting plate 1; the bottom end of the fifth driving wheel 407 is connected with a nitrogen supply mechanism 5; the left end of the seventh driving wheel 4019 is connected with the nitrogen supply mechanism 5; the bottom end of the eighteenth driving wheel 4020 is connected with the corner connecting pipe expanding mechanism 7.

The nitrogen supply mechanism 5 comprises a fixed bottom plate 501, a liquid nitrogen storage tank 502, a first nitrogen conveying pipe 503, a first air pump 504, a second nitrogen conveying pipe 505, an elastic pipe orifice 506, a buffer channel plate 507, a sliding plate 508, a first spring 509, a second spring 5010, abrasive paper 5011, a grinding wheel 5012, a linkage rod 5013, a magnetic fixed rod 5014, an attaching fixed plate 5015, an electromagnet 5016, a first bevel gear 5017, a second bevel gear 5018, an eighth transmission wheel 5019 and a connecting support plate 5020; the left side of the top end of the fixed bottom plate 501 is connected with a liquid nitrogen storage tank 502; the right side of the top end of the fixed bottom plate 501 is connected with a first air pump 504; the top end of the liquid nitrogen storage tank 502 is connected with a first nitrogen delivery pipe 503, and the right end of the first nitrogen delivery pipe 503 is connected with a first air pump 504; the middle part of the right end of the first air pump 504 is connected with a second nitrogen conveying pipe 505; a first bevel gear 5017 is arranged at the upper right part of the top end of the first air pump 504; the right end of the second nitrogen conveying pipe 505 is provided with an elastic pipe orifice 506; the upper right of the elastic pipe orifice 506 is connected with a buffer channel plate 507; the middle part of the front end of the elastic pipe orifice 506 is connected with a linkage rod 5013; the left end of the buffer channel plate 507 is connected with the sliding plate 508; the right end of the buffer channel plate 507 is provided with sand paper 5011; the left middle part of the bottom end of the sliding plate 508 is connected with a first spring 509; the right middle part of the bottom end of the falling plate 508 is connected with a second spring 5010; the outer side of the sand paper 5011 is connected with a grinding wheel 5012; the right end of the linkage rod 5013 is connected with a magnetic fixed rod 5014; the top end of the outer surface of the magnetic fixed rod 5014 is in sliding connection with the attaching fixed plate 5015; an electromagnet 5016 is arranged below the bottom end of the magnetic fixed rod 5014; the bottom end of the electromagnet 5016 is connected with a connecting support plate 5020; the bottom of the right end of the first bevel gear 5017 is meshed with the second bevel gear 5018; the middle part of the right end of the first bevel gear 5017 is rotatably connected with an eighth transmission wheel 5019; the left end of the outer surface of the first bevel gear 5017 is connected with the cutting and intercepting mechanism 4; the bottom of the left end of the liquid nitrogen storage tank 502 is connected with a welded junction feeding and brazing mechanism 8; the bottom end of the outer surface of the second bevel gear 5018 is connected with the cutting and intercepting mechanism 4; the bottom end of the eighth transmission wheel 5019 is connected with a welding port feeding and brazing mechanism 8; the bottom end of the connecting support plate 5020 is connected with the bottom support table 3; the left side of the bottom end of the second nitrogen conveying pipe 505 is connected with a welding port feeding and brazing mechanism 8.

The crater polishing and grinding mechanism 6 comprises a ninth driving wheel 601, a third bevel gear 602, a tenth driving wheel 603, a fourth bevel gear 604, an eleventh driving wheel 605, a cam 606, a spring rod 607, an in-pipe steel brush 608, a rotating clamping strip 609 and an impact block 6010; the middle part of the left end of the ninth driving wheel 601 is rotationally connected with the third bevel gear 602; the rear end of the outer surface of the third bevel gear 602 is in transmission connection with a tenth transmission wheel 603 through a belt; the rear side of the left end of the third bevel gear 602 is meshed with a fourth bevel gear 604; the middle part of the left end of the tenth transmission wheel 603 is rotationally connected with a spring rod 607; the rear end of the outer surface of the fourth bevel gear 604 is in transmission connection with an eleventh transmission wheel 605 through a belt; the middle part of the rear end of the eleventh driving wheel 605 is rotationally connected with the cam 606; the left end of the cam 606 is in transmission connection with an impact block 6010; the left end of the spring rod 607 is rotatably connected with the steel brush 608 in the pipe; the right side of the outer surface of the steel brush 608 in the pipe is rotatably connected with a rotating clamping strip 609; the bottom end of the ninth driving wheel 601 is connected with the corner connecting pipe expanding mechanism 7; the middle part of the right end of the tenth transmission wheel 603 is connected with a nitrogen supply mechanism 5; the middle part of the rear end of the eleventh transmission wheel 605 is connected with the nitrogen supply mechanism 5.

The corner connecting pipe expanding mechanism 7 comprises a table-shaped fixing seat 701, an edge limiting block 702, a right-angle refrigerant pipe 703, a special-shaped pipe expanding wheel 704, a helical gear 705, an electric telescopic rotating shaft 706, a twelfth driving wheel 707 and a nineteenth driving wheel 708; the middle part of the bottom end of the table-type fixed seat 701 is provided with an edge limiting block 702; the rear side in the table-shaped fixing seat 701 is connected with a right-angle refrigerant pipe 703; a special-shaped pipe expanding wheel 704 is arranged at the right end of the right-angle refrigerant pipe 703; the right end of the special-shaped pipe expanding wheel 704 is connected with a helical gear 705; the middle part of the right end of the bevel gear 705 is rotationally connected with an electric telescopic rotating shaft 706; the right end of the electric telescopic rotating shaft 706 is rotatably connected with a twelfth driving wheel 707; the middle part of the right end of the twelfth driving wheel 707 is rotationally connected with the nineteenth driving wheel 708; the top end of a nineteenth transmission wheel 708 is connected with a weld crater polishing and grinding mechanism 6; the top end of a twelfth driving wheel 707 is connected with the cutting and intercepting mechanism 4; the bottom end of the table-type fixing seat 701 is connected with the bottom supporting table 3.

The crater feeding and soldering mechanism 8 comprises a second air pump 801, a third nitrogen delivery pipe 802, a fourth nitrogen delivery pipe 803, a fuel storage tank 804, a fuel delivery pipe 805, a flame-surrounding type spray soldering device 806, a liquid solder storage tank 807, a solder delivery pipe 808, a spray soldering device 809, a fifth nitrogen delivery pipe 8010, a bearing seat 8011, a thirteenth driving wheel 8012, a fourteenth driving wheel 8013 and a fifteenth driving wheel 8014; the right side of the top end of the second air pump 801 is connected with a third nitrogen delivery pipe 802; the middle part of the right end of the second air pump 801 is connected with a fourth nitrogen conveying pipe 803; a fuel storage tank 804 is arranged at the rear right of the third nitrogen delivery pipe 802; the right side of the top end of the fuel storage tank 804 is connected with a fuel delivery pipe 805; the right end of fuel delivery pipe 805 is connected to flame-surrounding spray welding device 806; a liquid solder storage tank 807 is arranged above the top end of the flame surrounding type spray welding device 806; the bottom of the right end of the liquid solder storage tank 807 is connected with a solder delivery pipe 808; the right end of the solder conveying pipe 808 is connected with a solder spraying device 809; the middle part of the left end of the solder spraying device 809 is connected with a fifth nitrogen delivery pipe 8010; a bearing seat 8011 is arranged at the right end of the solder spraying device 809; the right end of the bearing seat 8011 is rotatably connected with a thirteenth driving wheel 8012; the middle part of the right end of the thirteenth driving wheel 8012 is rotatably connected with the fourteenth driving wheel 8013; the bottom end of the thirteenth driving wheel 8012 is in transmission connection with the fifteenth driving wheel 8014 through a belt; the bottom end of the second air pump 801 is connected with the bottom support platform 3; the bottom end of the fuel storage tank 804 is connected with the bottom support platform 3; the top of the right end of the third nitrogen conveying pipe 802 is connected with a nitrogen supply mechanism 5; the top end of the fifth nitrogen delivery pipe 8010 is connected with the nitrogen supply mechanism 5; the fourteenth driving wheel 8013 is connected to the nitrogen gas supplying unit 5 at its tip.

The special-shaped pipe expanding wheel 704 comprises an inner wheel 70401, a second lead screw 70402, a fifth bevel gear 70403 and an outer expanding ring 70404; the left middle upper part of the inner wheel 70401 is rotationally connected with a second screw rod 70402; the right lower part of the second screw rod 70402 is rotationally connected with a fifth bevel gear 70403; the upper left part of the second lead screw 70402 is rotationally connected with the external expansion ring 70404; the right end of the fifth bevel gear 70403 is connected with the bevel gear 705.

The flame encircling type spray welding device 806 comprises a flame welding gun 80601, a third flat gear 80602, a fourth flat gear 80603, a sixteenth driving wheel 80604, a seventeenth driving wheel 80605, a connecting synchronous bearing 80606, an L-shaped fixed pipe 80607, a rebound rod 80608 and a tail protection seat 80609; a third spur gear 80602 is arranged on the lower right of the flame welding gun 80601; the bottom end of the third flat gear 80602 is engaged with the fourth flat gear 80603; the bottom of the right end of the third spur gear 80602 is connected with a connecting synchronous bearing 80606; the middle part of the right end of the fourth flat gear 80603 is rotatably connected with a sixteenth driving wheel 80604; the bottom end of a sixteenth driving wheel 80604 is in transmission connection with a seventeenth driving wheel 80605 through a belt; the inner side of the connecting synchronous bearing 80606 is connected with an L-shaped fixed pipe 80607; the top of the front end of the L-shaped fixed pipe 80607 is connected with a rebound rod 80608; the bottom end of the resilient rod 80608 is connected with the tail protection seat 80609; the left end of flame welding gun 80601 is connected with fuel delivery pipe 805; the middle part of the right end of the seventeenth driving wheel 80605 is rotatably connected with the fifteenth driving wheel 8014; the left middle part of the bottom end of the flame welding gun 80601 is connected with the bottom support table 3; the bottom end of the connecting synchronous bearing 80606 is connected to the bottom support table 3.

The spray solder device 809 includes a first solder spray booth 80901, a nitrogen gas spray lance 80902, a second solder spray booth 80903, a first clip solder spray lance 80904, and a second clip solder spray lance 80905; the bottom end of the first solder firing chamber 80901 is connected to a nitrogen gas lance 80902; the middle lower part of the right end of the first solder ejection chamber 80901 is connected with a first clip-shaped solder ejection pipe 80904; the bottom end of the nitrogen gas nozzle 80902 is connected with a second solder firing chamber 80903; the right end of the second solder spray chamber 80903 is connected with a second clip-shaped solder spray pipe 80905; the left ends of the first solder spray chamber 80901 and the second solder spray chamber 80903 are connected with a solder delivery pipe 808; the left end of the nitrogen nozzle 80902 is connected to a fifth nitrogen delivery tube 8010.

The working principle is as follows: when the device is used, enough liquid nitrogen is added into a nitrogen supply mechanism 5, meanwhile, enough liquid solder is added into a welding port feeding brazing mechanism 8, enough flame welding gun 80601 fuel is added, then, an external power supply is connected, a control display screen 2 is turned on, then, a refrigerant copper pipe needing to be cut is cut and cut into an intercepted part through a cutting and intercepting mechanism 4, then, the inside and outside grinding and polishing of a welding port of a new cutting pipe are completed under the nitrogen filling protection effect of the nitrogen supply mechanism 5 in cooperation with a welding port polishing and grinding mechanism 6, then, a right-angle refrigerant pipe 703 is completed on a corner connecting pipe expanding mechanism 7, finally, the new cutting pipe and the right-angle cutting pipe are welded on the welding port feeding brazing mechanism 8, and the effective nitrogen filling protection automatic surrounding brazing and welding of the refrigerant copper pipe is achieved.

A refrigerant copper pipe to be cut is fixed through a fixed pipe sleeve 4010 and a pipe clamp 4011, meanwhile, the cut part of the refrigerant pipe is clamped in the middle of the inside of a cutting fixed shaft seat 4014, the tightness of a pipeline fixed inside the refrigerant copper pipe is adjusted through a locking buckle 4012, then, the right end of a motor 401 drives a first driving wheel 402 to rotate, further, the first driving wheel 402 drives a second driving wheel 403 to rotate, then, the bottom end of the second driving wheel 403 drives a first flat gear 405 to rotate through a third driving wheel 404, then, the first flat gear 405 drives a second flat gear 408 meshed with the top end of the first flat gear to rotate, meanwhile, the first flat gear 405 drives an eighteenth driving wheel 4020 at the right end of the second driving wheel through the rotation of a fourth driving wheel 406 and a fifth driving wheel 407, then, the top end of the fourth driving wheel 406 drives a sixth driving wheel 4013 to rotate through a belt, further, a rotary cutter 4015 is, and then slip ring 4017 and rotatory fixed bearing 4016 keep vertical rising state are connected in first lead screw 4018 normal running fit, and then drive rotary cutter 4015 upward movement, realize rotary cutter 4015 can upwards impel in the rotary cutting to in with refrigerant copper pipe complete cutting.

When the cutting of a new refrigerant pipe is completed, the cut part of the right end of the new refrigerant pipe slides to the inner side of the buffer channel plate 507 through the sliding plate 508, before the refrigerant pipe passes through the elastic pipe orifice 506, the elastic pipe orifice 506 changes direction and rotates from left to right, then the rear end of the refrigerant pipe is inserted into the elastic pipe orifice 506, at the moment, the power supply of the first air pump 504 is connected through the control display screen 2, then the liquid nitrogen stored in the liquid nitrogen storage tank 502 is pumped to the second nitrogen delivery pipe 505 through the first nitrogen delivery pipe 503 by the first air pump 504, and further the liquid nitrogen reaches the inside of the refrigerant pipe at the right end of the elastic pipe orifice 506 to ensure that the refrigerant pipe is not oxidized, then the power supply of the electromagnet 5016 is connected through the control display screen 2, then the electromagnet 5016 attracts the magnetic fixing rod 5014 at the top end of the refrigerant pipe to contact with the electromagnet, then the adhering fixing plate 5015 is adhered to the surface of the refrigerant pipe to fix the refrigerant pipe, then the grinding wheel, the frosted solder is easier to be attached to the solder, so that the welding effect is better.

After the refrigerant pipe is fixed by the nitrogen gas supply mechanism 5, the tenth transmission wheel 603 rotates to drive the spring rod 607 at the left end to rotate, meanwhile, the ninth transmission wheel 601 rotates to drive the third bevel gear 602 to rotate, then the rear side of the left end of the third bevel gear 602 drives the fourth bevel gear 604 meshed with the third bevel gear to rotate, further the fourth bevel gear 604 drives the eleventh transmission wheel 605 at the left end to rotate through a belt, then the eleventh transmission wheel 605 drives the cam 606 at the middle part of the rear end to rotate, when the protruding part of the cam 606 impacts the impact block 6010, the inertia impact block 6010 drives the spring rod 607 to drive the rotating clamping strip 609 at the left end to be inserted into the polishing wheel 5012 to drive the polishing wheel to rotate, and meanwhile, the steel brush 608 in the pipe extends into the refrigerant pipe to polish the inside of the welding port of the refrigerant pipe, thereby completing the polishing treatment inside the welding port of the refrigerant pipe.

The right-angle refrigerant pipe 703 is placed on the table-type fixing seat 701, the right-angle refrigerant pipe is limited by the edge limiting block 702, the electric telescopic rotating shaft 706 is controlled to be pushed leftwards by controlling the display screen 2, meanwhile, the special-shaped pipe expanding wheel 704 is driven to the inside of the refrigerant pipe, then the nineteenth driving wheel 708 drives the twelfth driving wheel 707 at the left end of the driving wheel to rotate, the twelfth driving wheel 707 drives the electric telescopic rotating shaft 706 to rotate, and then the bevel gear 705 is driven to rotate, so that the special-shaped pipe expanding wheel 704 is driven to expand a welded junction of the refrigerant pipe, and pipe expansion of the refrigerant pipe is completed.

Taking down the right-angle pipe after pipe expansion and the new pipe after grinding and polishing, inserting the new pipe into the bearing seat 8011, then the liquid solder storage tank 807 is opened and closed, the liquid solder reaches the solder spraying device 809 through the solder delivery pipe 808 to be subjected to the solder feeding device, then the fourteenth driving wheel 8013 rotates to drive the thirteenth driving wheel 8012 to rotate, then the thirteenth driving wheel 8012 drives the bearing seat 8011 to rotate, thereby realizing the rotary feeding of the refrigerant pipe, simultaneously, the fifth nitrogen conveying pipe 8010 carries out the inflation operation on the refrigerant pipe to ensure that the interior of the refrigerant pipe is not oxidized, then the feeding is completed, the refrigerant pipe and the right-angle pipe are placed in the flame surrounding type spray welding device 806 for final welding operation, meanwhile, the second air pump 801 charges nitrogen into the third nitrogen conveying pipe 802 and the fourth nitrogen conveying pipe 803, and brazing welding is completed under the condition that the interior of the refrigerant pipe is not oxidized.

When the bevel gear 705 rotates to drive the special-shaped pipe expanding wheel 704 to expand the welded junction of the refrigerant pipe, the bevel gear 705 rotates, then four groups of bevel gears including the fifth bevel gear 70403 are meshed with the bevel gear 705 at the same time, the four groups of bevel gears drive the screw rods which are connected with the bevel gears in a rotating mode to rotate respectively, then the outer expanding ring 70404 realizes the movement of the outer expanding ring 70404 from the center to the outside in the direction of continuously expanding the radius under the rotating fit of the screw rods, and then the four groups of outer expanding rings 70404 complete the pipe expansion of the welded junction of the refrigerant pipe at the same time, so that the radius of the welded junction of the refrigerant pipe is enlarged, and the.

Welding craters are manually inserted into a new pipe and a right-angle pipe, the right-angle pipe is inserted into the L-shaped fixed pipe 80607, the new pipe is inserted into the third flat gear 80602, the solder covering part is aligned with the edge of the welding crater, then the seventeenth driving wheel 80605 drives the sixteenth driving wheel 80604 at the top end of the seventeenth driving wheel to rotate through a belt, then the left end of the sixteenth driving wheel 80604 drives the fourth flat gear 80603 to rotate, then the fourth flat gear 80603 drives the third flat gear 80602 at the top end of the seventeenth driving wheel to rotate, which is meshed with the fourth flat gear 80603, then a fuel valve is opened, welding flames are sprayed out of the flame welding gun 80601, meanwhile, the third flat gear 80602 drives the connecting synchronous bearing 80606 and the L-shaped fixed pipe 80607 to rotate, further drives the refrigerant pipe fixedly connected inside the flame welding pipe to.

The solder enters the first solder spraying chamber 80901 and the second solder spraying chamber 80903, meanwhile, nitrogen enters the nitrogen spraying pipe 80902, and then the edges of the new pipe are respectively inserted into the middle parts of the upper and lower spraying pipes of the first clip-shaped solder spraying pipe 80904 and the second clip-shaped solder spraying pipe 80905, so that the feeding of the inner and outer welded junctions of the refrigerant pipe is realized.

The technical solutions of the present invention or similar technical solutions designed by those skilled in the art based on the teachings of the technical solutions of the present invention are all within the scope of the present invention to achieve the above technical effects.

Claims

1. A refrigerant pipe brazing device for a central air conditioner comprises a side supporting plate (1), a control display screen (2) and a bottom supporting table (3), and is characterized by further comprising a cutting and intercepting mechanism (4), a nitrogen supply mechanism (5), a welding opening polishing and grinding mechanism (6), a corner connecting pipe expanding mechanism (7) and a welding opening feeding brazing mechanism (8); a control display screen (2) is arranged in the middle of the left end of the side supporting plate (1); the bottom of the right end of the side supporting plate (1) is connected with the bottom supporting table (3); the top of the right end of the side supporting plate (1) is connected with a cutting and intercepting mechanism (4); the middle part of the right end of the side supporting plate (1) is connected with a nitrogen supply mechanism (5), and the upper left part of the nitrogen supply mechanism (5) is connected with a cutting and intercepting mechanism (4); the middle lower part of the right end of the side supporting plate (1) is connected with a welding port feeding brazing mechanism (8), and the top end of the welding port feeding brazing mechanism (8) is connected with a nitrogen supply mechanism (5); the bottom end of the welding port feeding and brazing mechanism (8) is connected with the bottom support table (3); the right side of the top end of the bottom supporting table (3) is connected with a welding port polishing and grinding mechanism (6), and the left end of the welding port polishing and grinding mechanism (6) is connected with a nitrogen supply mechanism (5); the right middle part of the top end of the bottom supporting table (3) is connected with a corner connecting pipe expanding mechanism (7).

2. The refrigerant pipe brazing device for the central air conditioner as claimed in claim 1, wherein the cutting and intercepting mechanism (4) comprises a motor (401), a first driving wheel (402), a second driving wheel (403), a third driving wheel (404), a first flat gear (405), a fourth driving wheel (406), a fifth driving wheel (407), a second flat gear (408), a rotating fixing rod (409), a fixing pipe sleeve (4010), a pipe clamp (4011), a locking buckle (4012), a sixth driving wheel (4013), a cutting fixing shaft seat (4014), a rotary cutter (4015), a rotary fixing bearing (4016), a connecting sliding ring (4017), a first screw rod (4018), a seventh driving wheel (4019) and an eighteenth driving wheel (4020); the middle part of the right end of the motor (401) is rotationally connected with the first transmission wheel (402); the middle part of the right end of the first driving wheel (402) is rotationally connected with a second driving wheel (403); the bottom end of the second driving wheel (403) is in transmission connection with a third driving wheel (404) through a belt; the middle part of the right end of the third driving wheel (404) is rotationally connected with the first flat gear (405); the middle part of the right end of the first flat gear (405) is rotationally connected with a fourth driving wheel (406); the top end of the first flat gear (405) is meshed with the second flat gear (408); the middle part of the right end of the fourth driving wheel (406) is rotationally connected with a fifth driving wheel (407); the top end of the fourth driving wheel (406) is in transmission connection with a sixth driving wheel (4013) through a belt; the middle upper part of the left end of the second flat gear (408) is connected with the upper part of the left end of the second flat gear; the inner middle part of the fifth transmission wheel (407) is in sliding connection with the rotating fixed rod (409); the right end of the fifth driving wheel (407) is rotationally connected with an eighteenth driving wheel (4020); the inner middle part of the second flat gear (408) is rotationally connected with the fixed pipe sleeve (4010); the left end of the fixed pipe sleeve (4010) is connected with a pipe clamp (4011); the right end of the outer surface of the fixed pipe sleeve (4010) is sleeved with a locking buckle (4012); the right end of the locking buckle (4012) is provided with a cutting fixed shaft seat (4014); a rotary cutter (4015) is arranged at the bottom in the cutting fixed shaft seat (4014), and the middle part of the left end of the rotary cutter (4015) is connected with a sixth driving wheel (4013); the middle part of the right end of the rotary cutter (4015) is rotationally connected with a rotary fixed bearing (4016); the right end of the rotary fixed bearing (4016) is connected with a connecting slip ring (4017); the middle part of the bottom end of the connecting slip ring (4017) is rotationally connected with a first screw rod (4018); the bottom end of the first screw rod (4018) is rotationally connected with a seventh driving wheel (4019); the left end of the motor (401) is connected with the side supporting plate (1); the middle part of the left end of the third driving wheel (404) is connected with the lateral support plate (1); the left end of the rotary fixing rod (409) is connected with the side supporting plate (1); the middle part of the right end of a sixth driving wheel (4013) is connected with a side supporting plate (1); the bottom end of the fifth driving wheel (407) is connected with a nitrogen supply mechanism (5); the left end of the seventh driving wheel (4019) is connected with a nitrogen supply mechanism (5); the bottom end of the eighteenth driving wheel (4020) is connected with the corner connecting pipe expanding mechanism (7).

3. The refrigerant pipe brazing device for the central air conditioner as claimed in claim 2, wherein the nitrogen supply mechanism (5) comprises a fixed base plate (501), a liquid nitrogen storage tank (502), a first nitrogen delivery pipe (503), a first air pump (504), a second nitrogen delivery pipe (505), an elastic pipe orifice (506), a buffer channel plate (507), a sliding plate (508), a first spring (509), a second spring (5010), abrasive paper (5011), a grinding wheel (5012), a linkage rod (5013), a magnetic fixed rod (5014), an attaching fixed plate (5015), an electromagnet (5016), a first bevel gear (5017), a second bevel gear (5018), an eighth transmission wheel (5019) and a connecting support plate (5020); the left side of the top end of the fixed bottom plate (501) is connected with a liquid nitrogen storage tank (502); the right side of the top end of the fixed bottom plate (501) is connected with a first air pump (504); the top end of the liquid nitrogen storage tank (502) is connected with a first nitrogen conveying pipe (503), and the right end of the first nitrogen conveying pipe (503) is connected with a first air pump (504); the middle part of the right end of the first air pump (504) is connected with a second nitrogen conveying pipe (505); a first bevel gear (5017) is arranged at the upper right of the top end of the first air pump (504); an elastic pipe orifice (506) is arranged at the right end of the second nitrogen conveying pipe (505); the upper right of the elastic pipe orifice (506) is connected with a buffer channel plate (507); the middle part of the front end of the elastic pipe orifice (506) is connected with a linkage rod (5013); the left end of the buffer channel plate (507) is connected with the slide-down plate (508); sand paper (5011) is arranged at the right end of the buffer channel plate (507); the left middle part of the bottom end of the sliding plate (508) is connected with a first spring (509); the right middle part of the bottom end of the sliding plate (508) is connected with a second spring (5010); the outer side of the sand paper (5011) is connected with a polishing wheel (5012); the right end of the linkage rod (5013) is connected with a magnetic fixed rod (5014); the top end of the outer surface of the magnetic fixed rod (5014) is in sliding connection with the attaching fixed plate (5015); an electromagnet (5016) is arranged below the bottom end of the magnetic fixed rod (5014); the bottom end of the electromagnet (5016) is connected with the connecting support plate (5020); the bottom of the right end of the first bevel gear (5017) is meshed with the second bevel gear (5018); the middle part of the right end of the first bevel gear (5017) is rotationally connected with an eighth transmission wheel (5019); the left end of the outer surface of the first bevel gear (5017) is connected with a cutting and intercepting mechanism (4); the bottom of the left end of the liquid nitrogen storage tank (502) is connected with a welding port feeding brazing mechanism (8); the bottom end of the outer surface of the second bevel gear (5018) is connected with a cutting and intercepting mechanism (4); the bottom end of the eighth transmission wheel (5019) is connected with a welding port feeding and brazing mechanism (8); the bottom end of the connecting support plate (5020) is connected with the bottom support table (3); the left side of the bottom end of the second nitrogen conveying pipe (505) is connected with a welding opening feeding and brazing mechanism (8).

4. The refrigerant pipe brazing device for the central air conditioner as claimed in claim 3, wherein the crater polishing and grinding mechanism (6) comprises a ninth driving wheel (601), a third bevel gear (602), a tenth driving wheel (603), a fourth bevel gear (604), an eleventh driving wheel (605), a cam (606), a spring rod (607), an in-pipe steel brush (608), a rotating clamping strip (609) and an impact block (6010); the middle part of the left end of the ninth transmission wheel (601) is rotationally connected with a third bevel gear (602); the rear end of the outer surface of the third bevel gear (602) is in transmission connection with a tenth transmission wheel (603) through a belt; the rear side of the left end of the third bevel gear (602) is meshed with the fourth bevel gear (604); the middle part of the left end of the tenth transmission wheel (603) is rotationally connected with a spring rod (607); the rear end of the outer surface of the fourth bevel gear (604) is in transmission connection with an eleventh transmission wheel (605) through a belt; the middle part of the rear end of the eleventh transmission wheel (605) is rotationally connected with the cam (606); the left end of the cam (606) is in transmission connection with an impact block (6010); the left end of the spring rod (607) is rotationally connected with the steel brush (608) in the pipe; the right side of the outer surface of the steel brush (608) in the pipe is rotationally connected with a rotating clamping strip (609); the bottom end of the ninth driving wheel (601) is connected with a corner connecting pipe expanding mechanism (7); the middle part of the right end of the tenth transmission wheel (603) is connected with a nitrogen supply mechanism (5); the middle part of the rear end of the eleventh transmission wheel (605) is connected with a nitrogen supply mechanism (5).

5. The refrigerant pipe brazing device for the central air conditioner as claimed in claim 4, wherein the corner connecting pipe expanding mechanism (7) comprises a table-shaped fixed seat (701), an edge limiting block (702), a right-angle refrigerant pipe (703), a special-shaped pipe expanding wheel (704), a helical gear (705), an electric telescopic rotating shaft (706), a twelfth driving wheel (707) and a nineteenth driving wheel (708); the middle part of the inner bottom end of the table-type fixed seat (701) is provided with an edge limiting block (702); the inner rear side of the table-shaped fixed seat (701) is connected with a right-angle refrigerant pipe (703); a special-shaped pipe expanding wheel (704) is arranged at the right end of the right-angle refrigerant pipe (703); the right end of the special-shaped pipe expanding wheel (704) is connected with the helical gear (705); the middle part of the right end of the bevel gear (705) is rotationally connected with an electric telescopic rotating shaft (706); the right end of the electric telescopic rotating shaft (706) is rotationally connected with a twelfth driving wheel (707); the middle part of the right end of the twelfth driving wheel (707) is rotationally connected with the nineteenth driving wheel (708); the top end of a nineteenth transmission wheel (708) is connected with a weld crater polishing and grinding mechanism (6); the top end of the twelfth driving wheel (707) is connected with the cutting and intercepting mechanism (4); the bottom end of the table-shaped fixed seat (701) is connected with the bottom supporting table (3).

6. The refrigerant pipe brazing device for the central air conditioner as claimed in claim 5, wherein the crater feeding brazing mechanism (8) comprises a second air pump (801), a third nitrogen delivery pipe (802), a fourth nitrogen delivery pipe (803), a fuel storage tank (804), a fuel delivery pipe (805), a flame-surrounding type spray welding device (806), a liquid solder storage tank (807), a solder delivery pipe (808), a spray welding device (809), a fifth nitrogen delivery pipe (8010), a bearing seat (8011), a thirteenth driving wheel (8012), a fourteenth driving wheel (8013) and a fifteenth driving wheel (8014); the right side of the top end of the second air pump (801) is connected with a third nitrogen conveying pipe (802); the middle part of the right end of the second air pump (801) is connected with a fourth nitrogen conveying pipe (803); a fuel storage tank (804) is arranged at the rear right part of the third nitrogen delivery pipe (802); the right side of the top end of the fuel storage tank (804) is connected with a fuel delivery pipe (805); the right end of the fuel delivery pipe (805) is connected with a flame surrounding type spray welding device (806); a liquid solder storage tank (807) is arranged above the top end of the flame surrounding type spray welding device (806); the bottom of the right end of the liquid solder storage tank (807) is connected with a solder delivery pipe (808); the right end of the solder conveying pipe (808) is connected with a solder spraying device (809); the middle part of the left end of the solder spraying device (809) is connected with a fifth nitrogen conveying pipe (8010); a bearing seat (8011) is arranged at the right end of the solder spraying device (809); the right end of the bearing seat (8011) is rotatably connected with a thirteenth driving wheel (8012); the middle part of the right end of the thirteenth driving wheel (8012) is rotatably connected with the fourteenth driving wheel (8013); the bottom end of the thirteenth driving wheel (8012) is in transmission connection with the fifteenth driving wheel (8014) through a belt; the bottom end of the second air pump (801) is connected with the bottom support platform (3); the bottom end of the fuel storage tank (804) is connected with the bottom support platform (3); the top of the right end of the third nitrogen conveying pipe (802) is connected with a nitrogen supply mechanism (5); the top end of the fifth nitrogen conveying pipe (8010) is connected with a nitrogen supply mechanism (5); the top end of the fourteenth driving wheel (8013) is connected with a nitrogen supply mechanism (5).

7. The refrigerant pipe brazing device for the central air conditioner as claimed in claim 6, wherein the special-shaped pipe expanding wheel (704) comprises an inner wheel (70401), a second lead screw (70402), a fifth bevel gear (70403) and an outer expanding ring (70404); the left middle upper part of the inner wheel (70401) is rotationally connected with a second screw rod (70402); the right lower part of the second screw rod (70402) is rotationally connected with a fifth bevel gear (70403); the upper left part of the second screw rod (70402) is rotationally connected with an external expanding ring (70404); the right end of a fifth bevel gear (70403) is connected with a bevel gear (705).

8. The refrigerant pipe brazing device for the central air conditioner as claimed in claim 7, wherein the flame-looping type spray welding device (806) comprises a flame welding gun (80601), a third flat gear (80602), a fourth flat gear (80603), a sixteenth driving wheel (80604), a seventeenth driving wheel (80605), a connecting synchronous bearing (80606), an L-shaped fixed pipe (80607), a rebound rod (80608) and a tail protection seat (80609); a third spur gear (80602) is arranged on the lower right of the flame welding gun (80601); the bottom end of the third flat gear (80602) is meshed with the fourth flat gear (80603); the bottom of the right end of the third spur gear (80602) is connected with a connecting synchronous bearing (80606); the middle part of the right end of the fourth flat gear (80603) is rotationally connected with a sixteenth driving wheel (80604); the bottom end of the sixteenth driving wheel (80604) is in transmission connection with a seventeenth driving wheel (80605) through a belt; the inner side of the connecting synchronous bearing (80606) is connected with an L-shaped fixed pipe (80607); the top of the front end of the L-shaped fixed pipe (80607) is connected with a rebound rod (80608); the bottom end of the rebound rod (80608) is connected with the tail protection seat (80609); the left end of the flame welding gun (80601) is connected with a fuel delivery pipe (805); the middle part of the right end of the seventeenth driving wheel (80605) is rotationally connected with the fifteenth driving wheel (8014); the left middle part of the bottom end of the flame welding gun (80601) is connected with the bottom support platform (3); the bottom end of the connecting synchronous bearing (80606) is connected with the bottom support platform (3).

9. The refrigerant pipe brazing device for the central air conditioner as claimed in claim 8, wherein the solder spraying device (809) comprises a first solder spraying chamber (80901), a nitrogen gas spraying pipe (80902), a second solder spraying chamber (80903), a first clip-shaped solder spraying pipe (80904) and a second clip-shaped solder spraying pipe (80905); the bottom end of the first solder spraying chamber (80901) is connected with a nitrogen spraying pipe (80902); the middle lower part of the right end of the first solder spraying chamber (80901) is connected with a first clip-shaped solder spraying pipe (80904); the bottom end of the nitrogen gas spray pipe (80902) is connected with a second solder spraying chamber (80903); the right end of the second solder spray chamber (80903) is connected with a second clip-shaped solder spray pipe (80905); the left ends of the first solder spray chamber (80901) and the second solder spray chamber (80903) are connected with a solder delivery pipe (808); the left end of the nitrogen nozzle (80902) is connected with a fifth nitrogen conveying pipe (8010).