CN110919187B

CN110919187B - Laser spot welding machine and production process of range hood applying same

Info

Publication number: CN110919187B
Application number: CN201911413838.2A
Authority: CN
Inventors: 罗丹丹; 黄超年; 蒋英; 易智能; 林红
Original assignee: Shaoxing Elio Kitchenware Co ltd
Current assignee: Shaoxing Elio Kitchenware Co ltd
Priority date: 2019-12-31
Filing date: 2019-12-31
Publication date: 2022-02-18
Anticipated expiration: 2039-12-31
Also published as: CN110919187A

Abstract

The invention relates to a laser spot welder and a production process of a range hood applying the laser spot welder, and relates to the technical field of welding equipment. The welding piece is clamped by the first clamping block and the second clamping block, so that the welding piece is fixed, the possibility of gaps of the welding piece is reduced, the possibility of non-welding of the laser during welding is reduced, the welding quality is improved, and the defective rate is reduced.

Description

Laser spot welding machine and production process of range hood applying same

Technical Field

The invention relates to the technical field of welding equipment, in particular to a laser spot welding machine and a production process of a range hood applying the laser spot welding machine.

Background

Laser spot welding is the localized heating of materials in small areas by high energy laser pulses, the energy of the laser radiation diffusing through heat transfer into the material to melt the material and form a specific melt pool, thereby welding the same or different materials together.

As shown in fig. 1, the conventional laser spot welding machine includes a frame 1, wherein a transverse adjusting frame 41 is arranged on the frame 1, a longitudinal adjusting frame 42 is slidably arranged on the transverse adjusting frame 41, and a workbench 3 is slidably arranged on the longitudinal adjusting frame 42; a screw motor is arranged in the transverse adjusting frame 41, and a connecting block connected with a screw of the screw motor is arranged at the bottom of the longitudinal adjusting frame 42, so that the screw motor drives the connecting block to move, the process that the longitudinal adjusting frame 42 slides on the transverse adjusting frame 41 is realized, and the workbench 3 slides on the longitudinal adjusting frame 42 in the same structure; the upper surface of the workbench 3 is provided with a square limiting frame 36, and the rack 1 above the limiting frame 36 is provided with a laser 2. In the actual use process, the metal frame and the metal plate are attached to one side of the limiting frame 36, and then the metal frame and the metal plate are attached to one side of the limiting frame 36 by other objects, so that simple fixation is realized, and the attachment part of the metal frame and the limiting frame is welded by the laser 2.

The technical scheme has the following defects: in the welding process, the vertical sliding frame and the shaking generated by the movement of the working platform can cause a gap between the metal frame and the metal plate to be formed and not to be attached, and when the laser irradiation position is not attached, the metal frame and the metal plate cannot be welded; and foreign objects can not tightly abut against the metal frame and the metal plate, and the metal frame and the metal plate can not be welded because the foreign objects are not tightly attached, so that the welding efficiency is greatly influenced.

Disclosure of Invention

Aiming at the defects in the prior art, the first purpose of the invention is to provide a laser spot welding machine, which can fix a welding piece, reduce the possibility of generating gaps on the welding piece, reduce the possibility of generating non-welding when a laser is used for welding, improve the welding quality and reduce the defective rate.

The first invention is realized by the following technical scheme:

the utility model provides a laser spot welder, includes the frame, be provided with laser instrument, observation mechanism, moving mechanism in the frame, the last workstation that is provided with of moving mechanism, be provided with fixture on the workstation, fixture is including installing perpendicularly fixed frame on the workstation, the interval level is slided and is provided with two and removes the seat on the fixed frame, remove and install first grip block on the seat, remove on the seat slide be provided with the second grip block that first grip block corresponds, first grip block with the relative one side of second grip block forms the space that is used for the centre gripping weldment, be provided with on the fixed frame with the first drive assembly that the second grip block is connected, just be provided with on the fixed frame with two remove the seat and connect and can drive two remove the second drive assembly that the seat was relative motion.

Through adopting above-mentioned technical scheme, when the weldment needs to be fixed, the second drive assembly drives two and removes the seat and remove, until the weldment both ends all between first grip block and second grip block, first drive assembly is driving the motion of second grip block, make first grip block and the tight weldment of second grip block clamp, realize the fixed of butt welding spare, the probability in gap has been reduced to the weldment, thereby greatly reduced the unwelded possibility of laser appearance when the welding, the welded quality has been improved, the defective percentage is reduced, the waste of material has also been reduced simultaneously. The movable adjustment setting of two movable blocks makes can satisfy the welding demand of different length, has improved the suitability.

The present invention may further be configured in a preferred example, wherein the second driving assembly includes a second screw rod rotatably installed on the fixed frame and in threaded engagement with the two movable seats, and a second motor installed on the fixed frame and connected to one end of the second screw rod, the second screw rod has two opposite threaded sections, and the two movable seats are in threaded engagement with the two threaded sections respectively.

Through adopting above-mentioned technical scheme, when first grip block and second grip block messenger weldment is in between first grip block and the second grip block need be removed, the second motor drives the second screw rod and rotates, and two screw sections of second screw rod drive two motion seats movements respectively to the realization is with first grip block and second grip block motion to the position that can the centre gripping weldment.

In a preferred example, the fixed frame is in a rectangular frame shape, two moving seats are arranged on two horizontal long sides of the fixed frame, and two vertically corresponding moving seats are connected with a vertical moving column; two long edges of the fixed frame are both rotatably provided with second screw rods, one end of the fixed frame at the same side of the second screw rods penetrates out of the fixed frame, a first linkage rod is rotatably arranged on a vertical wide edge of the fixed frame at one side of the penetrating second screw rods, two ends of the first linkage rod are respectively meshed and connected with one end of the penetrating second screw rods through a first bevel gear, and the second motor is connected with one end of any penetrating second screw rod;

the movable column is provided with lifting blocks in a vertical sliding manner, the first clamping block, the second clamping block and the first driving assembly are mounted on the lifting blocks, and the fixed frame is provided with a third driving assembly which is connected with the two lifting blocks and the second motor; the first driving assembly comprises a first air cylinder installed on the lifting block and a connecting block installed on a piston rod of the first air cylinder and connected with the first clamping block, and the telescopic direction of the piston rod of the first air cylinder is parallel to the sliding direction of the second clamping block.

Through adopting above-mentioned technical scheme, because weldment height difference, if want the centre gripping stable, then need press from both sides at different heights. The second motor drives the third driving assembly, and the third driving assembly drives the lifting block to lift, so that the heights of the first clamping block and the second clamping block are lifted, and clamping of different height positions of the butt welding piece is realized. And the second motor drives the two second screw rods to rotate through the first linkage rod, so that the synchronous motion of the moving seats is realized, and the same moving column is synchronously driven by the two moving seats, so that the moving column has higher precision in the moving process, the probability of inclination is greatly reduced, and the probability of clamping due to inclination is greatly reduced. When the clamping is needed, the first air cylinder drives the second clamping block to move, so that the first clamping block and the second clamping block are close to each other, and the clamping of the weldment is realized.

In a preferred example, the second motor is slidably disposed on the fixing frame along an axial direction of the second screw, and the fixing frame is provided with a second cylinder connected to the second motor;

the third driving assembly comprises a third screw rod, two first worm sleeves, a first worm wheel, a second linkage rod and a second worm sleeve, wherein two ends of the third screw rod are rotatably installed on two corresponding movable seats, the third screw rod is parallel to the movable column and is in threaded fit with the lifting block, the two first worm sleeves are rotatably installed on the same long edge of the fixed frame respectively, the first worm wheel is coaxially installed on the third screw rod and is meshed with the first worm sleeves, two ends of the second linkage rod are rotatably connected with two wide edges of the fixed frame respectively and slide through the two first worm sleeves, the second linkage rod and the first worm sleeves are circumferentially fixed and slide axially, and one end of the second linkage rod penetrates through the fixed frame and is provided with a first gear;

the output shaft of the second motor is coaxially provided with a second gear meshed with the first gear, the teeth of the first gear and the teeth of the second gear are provided with chamfers, the output shaft of the second motor is also coaxially provided with a second bevel gear meshed with the first bevel gear, and when the second cylinder drives the second motor to slide, the second bevel gear can be meshed with the first bevel gear or the first gear can be meshed with the second gear.

Through adopting above-mentioned technical scheme, when the elevator that needs go up and down, the second cylinder drives the second motor and slides for first gear and second gear meshing, and make first bevel gear and second bevel gear separation, the second motor drives the rotation of second linkage pole, and first worm cover and second linkage pole synchronous rotation, first worm cover drive first worm wheel and rotate, and the third screw rod rotates with first worm wheel synchronous, thereby realizes the lift to the elevator. Through the lift of second motor control elevator and the removal of removing the seat, reduced the use of motor, compare in the cylinder, the cylinder is not fragile, and wearing and tearing are less, therefore the probability that breaks down can reduce.

The invention may further be configured in a preferred example, the moving mechanism includes a transverse adjusting frame arranged on the rack, a longitudinal adjusting frame is slidably arranged on the transverse adjusting frame, a fourth driving assembly connected with the longitudinal adjusting frame is arranged on the transverse adjusting frame, the workbench is slidably arranged on the longitudinal adjusting frame, and a fifth driving assembly connected with the workbench is arranged on the longitudinal adjusting frame;

the fourth driving assembly comprises a first threaded rod which is rotatably installed on the transverse adjusting frame and the axis direction of which is parallel to the length direction of the transverse adjusting frame, a first installation block of which at least two threads are installed on the first threaded rod, a first rotating shaft which is installed on the first installation block and the two ends of which extend out of the first kidney-shaped channel, a first fixing frame which is installed on the lower surface of the longitudinal adjusting frame and is rotatably connected with the first rotating shaft, a first supporting wheel which is rotatably installed on the first rotating shaft and rolls on the side wall of the first sinking groove, and a first driving motor which is installed on the transverse adjusting frame and is connected with the first threaded rod;

vertical alignment jig is provided with the heavy groove of second along length direction's both sides are sunken, the second waist shape passageway has been seted up to the tank bottom in the heavy groove of second, fifth drive assembly installs including rotating vertical alignment jig is last and axis direction with the parallel second threaded rod of length direction of vertical alignment jig, two at least threads are installed second installation piece on the second threaded rod, install on the second installation piece and both ends stretch out the second axis of rotation of second waist shape passageway, install the workstation lower surface and with second axis of rotation rotate the second mount, the rotation of connecting and install in the second axis of rotation just is in rolling second supporting wheel on the lateral wall in the heavy groove of second, second threaded rod one end is stretched out outside vertical alignment jig.

Through adopting above-mentioned technical scheme, when placing the weldment, the length direction that the weldment needs the welded limit is parallel with the length direction of horizontal alignment jig, and in the motion process, first driving motor drives first threaded rod and rotates, and first threaded rod drives first installation piece motion, first axis of rotation and first installation piece synchronous motion, first mount and first axis of rotation synchronous motion, and first supporting wheel rolls at the lateral wall in first heavy groove, realizes the gliding movement of vertical alignment jig. In the welded process, the offset may appear in its side direction, therefore when appearing the offset, the staff rotates the second threaded rod, and the second threaded rod drives the motion of second installation piece, second axis of rotation and second installation piece synchronous motion, second mount and second axis of rotation synchronous motion, and the second supporting wheel rolls at the lateral wall of the heavy groove of second, realizes the regulation of workstation.

The invention may further be configured in a preferred example, a rack is arranged on the side wall of the first sinking groove, which is in contact with the first supporting wheel, and a gear ring meshed with the rack is arranged on the outer wall of the first supporting wheel; the gear ring is provided with an annular groove with a triangular cross section along the annular direction, and the rack is provided with a limit belt matched with the annular groove along the length direction.

Through adopting above-mentioned technical scheme, the cooperation of rack and ring gear makes first supporting wheel can not appear skidding the phenomenon when rotating to the repeated welded possibility appears when having reduced the welding, thereby can improve welded quality. Simultaneously, through the arrangement of the limiting belt and the annular groove, the possibility of left and right deviation of the first supporting wheel in the rolling process is reduced, the accuracy in moving is improved, and the welding effect is improved.

In a preferred example, the first fixing frame is provided with dust suction pipes aligned with the upper surface of the rack, and one first fixing frame is provided with two dust suction pipes which are respectively positioned at two sides of the first supporting wheel;

the first fixing frame is provided with a driving piece, the driving piece is connected with an extension rod, the extension rod is rotatably provided with a sponge wheel soaked with lubricating oil, and the driving piece can drive the extension rod to lift;

the extension rod still is provided with the oil storage tank, contain lubricating oil in the oil storage tank, the oil storage tank is located the below of sponge wheel, just sponge wheel part soaks in the lubricating oil of oil storage tank.

Through adopting above-mentioned technical scheme, because can pile up the dust particle on the rack, consequently jolt phenomenon can appear when first supporting wheel passes through to welding position's when influence welding skew has reduced the welded accuracy nature. Through the setting of dust absorption pipe, can take away the dust particle on the rack for when first supporting wheel rolls, the probability greatly reduced of jolting, thereby improved welded stability.

After long-time use, frictional force between ring gear and the rack can be great, and easy wearing and tearing through the setting of sponge wheel and oil storage tank, when needs lubricate, the driving piece drives the extension rod downstream for the sponge wheel supports tightly with the outer wall of ring gear, and rotates under the drive of ring gear, thereby lubricates all global of ring gear, reduces the friction. The lubricating oil on the sponge wheel can be supplemented by the arrangement of the oil storage tank. Meanwhile, the dust collection pipe is used for enabling dust particles mixed with lubricating oil added on the rack to be small, and influences on the lubricating agent can be reduced.

In a preferred example of the present invention, the observation mechanism may further include an L-shaped bracket disposed on the lateral adjustment bracket, the bracket is provided with a display screen, the laser is provided with a camera for shooting toward the welding position and electrically connected to the display screen, and the laser is further provided with a lamp for illuminating toward the welding position;

the second threaded rod is worn out vertical alignment jig one end is provided with the second worm wheel, the support rotates installs length direction and is on a parallel with vertical alignment jig sliding direction's bull stick, the slip cover on the bull stick be equipped with the second worm cover of second worm wheel meshing, the second worm cover with bull stick circumference is fixed.

Through adopting above-mentioned technical scheme, the staff makes the welding position that needs according to the laser instrument judge rotating the second threaded rod, but it is comparatively troublesome directly to see welding position. Through the setting of camera, lamp and display screen, the staff can directly see the welding position when welding through the display screen. And have in welding process, vertical slip frame can move on horizontal slip frame for the position of second threaded rod is changeing all the time, and the staff of being inconvenient for adjusts. Through the setting of bull stick, second worm cover, second worm wheel, second worm cover and second worm wheel screw-thread fit, rotate the bull stick and drive second worm cover and rotate, second worm cover drives the rotation of second worm wheel to the rotation of realization to the second threaded rod.

In a preferred example of the present invention, the bracket may further be provided with an operating rod parallel to the rotating rod, one end of the operating rod is rotatably connected to the bracket, the operating rod is in transmission connection with the rotating rod through a gear, and the other end of the operating rod is located below the display screen and is provided with a rotating block.

Through adopting above-mentioned technical scheme, because the second worm cover moves on the bull stick, the motion route is longer, and the staff will be in the control of bull stick tip when the operation, and is comparatively troublesome, through the setting of action bars for operating personnel can directly rotate when seeing the display screen, need not to rotate at the bull stick tip, and is comparatively convenient.

The second purpose of the invention is to provide a production process of the range hood, which enables crystal grains in a welding line formed in the primary welding process to be thinned, so that the defects of the welding line are reduced, and the mechanical property strength of the welding line is improved.

The second invention purpose of the invention is realized by the following technical scheme:

a production process of a range hood comprises the following process steps:

s1: cutting a stainless steel raw material to obtain a raw material composite board;

s2: bending and stamping the raw material composite board to obtain a finished product composite board;

s3: combining the finished combined plates, and welding by a laser spot welding machine to form a primary welding line as in the first invention purpose to obtain a semi-finished lampblack shell; the welding surface of the combined plate is pretreated before welding;

s4: polishing a primary welding line on the semi-finished product lampblack shell;

s5: observing the polished welding line, and performing repair welding on the defective welding point on the polished welding line by using a laser spot welding machine as in the first invention purpose to obtain a finished product lampblack shell;

s6: assembling the finished product of the range hood casing into a whole machine to obtain the range hood;

s7: carrying out aging test on the range hood, and packaging after the test is qualified;

the preprocessing in step S3 is as follows:

step a: cleaning the welding surface of the finished composite board by using hot alkali liquor with the pH of 8-9 and the temperature of 50-60 ℃, washing by using deionized water, and drying for later use;

step b: welding reinforcers are preset on the welding surface and comprise the following components in percentage by weight:

30-60% of active agent;

10-20% of ferrotitanium powder;

20-50% of Cr, Ni and stainless steel mixed powder;

wherein the active agent comprises the following components in percentage by weight:

10-15% of sodium fluoride;

6-10% of calcium fluoride;

5-8% of silicon dioxide;

70-80% of acetone;

wherein the mass ratio of the Cr powder to the Ni powder to the stainless steel powder is 1: 2-3: 3-5.

Through adopting above-mentioned technical scheme, the welding is assembled to raw and other materials stainless steel plate to lampblack absorber casing adoption first welding and repair welding. In the process of primary welding, the welding surface is pretreated, so that crystal grains in a welding seam formed in the primary welding process become thin, the defects of the welding seam are reduced, and the mechanical property strength of the welding seam is improved. Meanwhile, by adopting the laser spot welding machine in the first invention, the welding precision can be greatly improved, and the possibility of welding position deviation is reduced, so that the high quality of the range hood is ensured.

The finished composite board is cleaned by hot alkali liquor before welding to remove oil stains on the surface of a welding surface, and then is cleaned by deionized water, so that the oil stains can not influence the welding of the composite board, and the defects of air hole cracks and the like are not easy to generate in the welding process.

After cleaning and welding, a layer of welding reinforcer is preset on the welding surface, and Cr powder, Ni powder and stainless steel powder contained in the welding reinforcer are melted to form alloying in the welding process, so that molten metal at the welding seam is recrystallized or some strong carbonitride forming elements form compounds with carbon or nitrogen in steel or serve as heterogeneous nucleation substrates or block the growth of crystal grains, the grain refinement at the welding seam is realized, and the mechanical property of the welding seam is improved.

After the ferrotitanium powder is preset on a welding surface, when welding, titanium element can be combined with carbon element and nitrogen element to form tiny titanium carbide and titanium nitride compounds, and the tiny compounds are in dispersion distribution, so that the growth of a grain structure is reduced, the grain structure of a welding seam is tiny, the mechanical property of the welding seam is improved, and the strength of the welding seam is increased. The addition of the iron powder and the stainless steel powder improves the concentration of iron elements on a welding surface, so that during welding, molten iron is molten from the welding surface and is also molten from a welding reinforcer, the molten iron and other components in the welding reinforcer are molten more quickly and sufficiently, and the welding tightness is improved. Meanwhile, due to the low carbon content in the stainless steel, a certain amount of carbon element can be provided in the common iron powder to provide combination with the titanium element.

The surface tension of liquid metal in a common welding molten pool has a negative temperature coefficient, the surface tension value of a region with lower temperature at the edge of the molten pool is higher, surface tension flow from the central region of the molten pool to the periphery of the molten pool is formed on the surface of the molten pool, and a shallow and wide molten pool is formed; when the active agent is added into the molten pool metal, the surface tension value of the molten pool liquid metal can be reduced and converted into a positive temperature coefficient by the active agent, so that the molten pool metal forms surface tension flow from the periphery of the molten pool to the central area of the molten pool, the heat in the central area of the molten pool is directly transferred to the bottom of the molten pool through liquid flow, the heating efficiency of the bottom of the molten pool is improved, a narrow and deep molten pool is formed, and the welding seam obtained by primary welding is more uniform, has fewer defects and has higher structural strength.

The sodium fluoride, the calcium fluoride and the silicon dioxide have the effect of increasing the weld penetration, wherein the effect of the fluoride is better than that of the oxide, and the sodium fluoride has the most obvious effect of deepening the weld. When a plurality of fluorides and oxides are adopted for matching, the welding effect is better than that when the active agent with single component is added for welding. Acetone is volatile, and when acetone is volatilized, powder in the active agent is adhered to the surface of the welding surface.

In summary, the invention includes at least one of the following beneficial technical effects:

1. the first clamping block and the second clamping block clamp the weldment tightly, so that the weldment is fixed, and the possibility of gaps of the weldment is reduced, the possibility of non-welding of the laser during welding is reduced, the welding quality is improved, and the defective rate is reduced;

2. the second motor drives the third driving assembly, and the third driving assembly drives the lifting block to lift, so that the first clamping block and the second clamping block are lifted in height, and clamping of the welding piece at different height positions is realized; the second motor drives the two second screw rods to rotate through the first linkage rod, so that synchronous motion of the moving seats is realized, the same moving column is synchronously driven by the two moving seats, the precision of the moving column in the moving process is high, the probability of inclination is greatly reduced, and the probability of clamping due to inclination is reduced;

3. the lifting of the lifting block and the movement of the moving seat are controlled by the second motor, so that the use of the motor is reduced, and compared with an air cylinder, the air cylinder is not easy to damage and has small abrasion, so that the failure probability is reduced;

4. through the arrangement of the camera, the lamp and the display screen, a worker can directly see the welding position during welding through the display screen; through the arrangement of the rotating rod, the second worm sleeve and the second worm wheel, the second worm sleeve is in threaded fit with the second worm wheel, the rotating rod is rotated to drive the second worm sleeve to rotate, and the second worm sleeve drives the second worm wheel to rotate, so that the second threaded rod is rotated;

5. by presetting the welding reinforcer on the welding surface during initial welding, crystal grains in a welding line formed in the initial welding process become thin, so that the defects of the welding line are reduced, and the mechanical property strength of the welding line is improved.

Drawings

Fig. 1 is a schematic view of a three-dimensional structure of a conventional laser spot welder;

FIG. 2 is a schematic diagram of a three-dimensional structure according to a first embodiment of the present invention;

FIG. 3 is a schematic diagram of a partial perspective structure of a moving mechanism according to one embodiment of the present invention;

FIG. 4 is an enlarged schematic view of portion A of FIG. 3;

FIG. 5 is an enlarged schematic view of section B of FIG. 2;

FIG. 6 is a schematic diagram of a partial perspective view of a viewing mechanism in accordance with one embodiment of the present invention;

FIG. 7 is an enlarged schematic view of section C of FIG. 2;

fig. 8 is an enlarged schematic view of a portion D in fig. 2.

Reference numerals: 1. a frame; 2. a laser; 21. a fan; 22. a water tank; 221. a bottom box; 222. a top cover; 223. an air supply pipe; 224. an air inlet pipe; 3. a work table; 31. a fixing frame; 311. a movable seat; 312. moving the column; 313. a first linkage rod; 314. a first bevel gear; 315. a second bevel gear; 317. a second cylinder; 322. a second motor; 323. a second gear; 33. a lifting block; 331. a first clamping block; 332. a second clamping block; 333. a rubber cushion layer; 34. a third drive assembly; 341. a third screw; 342. a first worm housing; 343. a first worm gear; 344. a second linkage rod; 345. a first gear; 35. a first drive assembly; 351. a first cylinder; 352. connecting blocks; 36. a limiting frame; 41. a transverse adjusting bracket; 411. a first sink tank; 412. a first kidney channel; 42. a longitudinal adjusting bracket; 421. a second sink tank; 422. a second kidney channel; 432. a first mounting block; 433. a first rotating shaft; 434. a first fixing frame; 435. a first support wheel; 436. a first drive motor; 441. a second threaded rod; 442. a second mounting block; 443. a second rotating shaft; 444. a second fixing frame; 445. a second support wheel; 451. a ring gear; 452. a rack; 453. an annular groove; 454. a limiting band; 46. a dust collection pipe; 471. an extension rod; 473. a sponge wheel; 474. a drive member; 475. an oil storage tank; 5. a support; 51. a display screen; 53. a lamp; 541. a second worm gear; 542. a second worm housing; 55. a rotating rod; 56. an operating lever; 57. and (6) turning the block.

Detailed Description

The present invention is described in further detail below with reference to the attached drawings.

The first embodiment is as follows:

referring to fig. 2, a laser spot welding machine, including frame 1, be provided with laser instrument 2, observation mechanism, moving mechanism on the frame 1, the last workstation 3 that is provided with of moving mechanism, laser instrument 2 is used for welding the weldment, and observation mechanism supplies the staff to look over the condition of welding position, and moving mechanism drives the 3 removal of workstation and realizes the welding of laser instrument 2 butt welding, is provided with the fixture who is used for the centre gripping weldment on the workstation 3.

Referring to fig. 2 and 3, the moving mechanism includes a transverse adjusting frame 41 and a longitudinal adjusting frame 42, the transverse adjusting frame 41 is fixedly disposed on the frame 1, the longitudinal adjusting frame 42 is slidably disposed on the transverse adjusting frame 41, a fourth driving assembly connected to the longitudinal adjusting frame 42 is disposed on the transverse adjusting frame 41, the workbench 3 is disposed on the longitudinal adjusting frame 42, and a fifth driving assembly connected to the workbench 3 is disposed on the longitudinal adjusting frame 42.

The transverse adjusting frame 41 is concavely provided with first sinking grooves 411 along two sides of the length direction, a first waist-shaped channel 412 is formed in the bottom of each first sinking groove 411, the length direction of each first waist-shaped channel 412 is parallel to the length direction of each first sinking groove 411, each fourth driving component comprises a first threaded rod (not shown in the figure), a first mounting block 432, a first rotating shaft 433, a first fixing frame 434, a first supporting wheel 435 and a first driving motor 436, the first threaded rods are rotatably mounted at two ends of the length direction of the transverse adjusting frame 41, and the axis direction of the first threaded rods is parallel to the length direction of the transverse adjusting frame 41; two first mounting blocks 432 are arranged, and spaced threads are arranged on the first threaded rod; the first rotating shaft 433 is rotatably installed on the first installation block 432, two ends of the first rotating shaft 433 extend out of the first kidney-shaped channel 412, and the axial direction of the first rotating shaft 433 is perpendicular to the axial direction of the first threaded rod.

Two first fixing frames 434 are arranged and correspond to the two first mounting blocks 432 in a one-to-one manner, the first fixing frames 434 are fixedly mounted on the lower surface of the longitudinal adjusting frame 42 and are rotatably connected with the first rotating shafts 433 on the corresponding first mounting blocks 432, and the lower surface of the longitudinal adjusting frame 42 is not in contact with the upper surface of the transverse adjusting frame 41, so that a gap is formed between the lower surface of the longitudinal adjusting frame 42 and the upper surface of the transverse adjusting frame 41, and friction force and abrasion are reduced; four first supporting wheels 435 are provided, one first rotating shaft 433 corresponds to two first supporting wheels 435, the two corresponding first supporting wheels 435 are respectively installed at two ends of the first rotating shaft 433 extending out of the first kidney-shaped channel 412, and the first supporting wheels 435 roll on the side wall of the first sinking groove 411; the first driving motor 436 is fixedly installed on an outer wall of one end of the transverse adjusting frame 41 in the length direction, one end of the first threaded rod extends out of the transverse adjusting frame 41, and the first driving motor 436 is connected with the extended end of the first threaded rod.

The first driving motor 436 drives the first threaded rod to rotate, the first threaded rod drives the first mounting block 432 to move, the first rotating shaft 433, the first fixing frame 434, the longitudinal adjusting frame 42 and the first mounting block 432 synchronously move, and the first supporting wheel 435 rolls when the first rotating shaft 433 moves, so that the sliding adjustment of the longitudinal adjusting frame 42 is realized.

The length direction of the longitudinal adjusting frame 42 is perpendicular to the length direction of the transverse adjusting frame 41, second sinking grooves 421 are concavely arranged on two sides of the longitudinal adjusting frame 42 along the length direction, and second waist-shaped channels 422 are formed at the bottoms of the second sinking grooves 421. The fifth driving assembly comprises a second threaded rod 441, a second mounting block 442, a second rotating shaft 443, a second fixing frame 444 and a second supporting wheel 445, the second threaded rod 441 is rotatably mounted at two ends of the longitudinal adjusting frame 42 in the length direction, the axial direction of the second threaded rod 441 is parallel to the length direction of the longitudinal adjusting frame 42, and one end of the second threaded rod 441 penetrates out of the longitudinal adjusting frame 42; two second mounting blocks 442 are provided, and are mounted on the second threaded rod 441 at intervals; the second rotating shaft 443 is rotatably installed on the second installation block 442 with both ends thereof protruding out of the second kidney passage 422, and the axial direction of the second rotating shaft 443 is perpendicular to the axial direction of the second threaded rod 441.

Two second fixing frames 444 are in one-to-one correspondence with the two second mounting blocks 442, the second fixing frames 444 are fixedly mounted on the lower surface of the workbench 3 and are rotatably connected with the second rotating shafts 443 on the corresponding second mounting blocks 442, and the lower surface of the longitudinal workbench 3 is not in contact with the upper surface of the longitudinal adjusting frame 42, so that a gap is formed, friction force is reduced, and abrasion is reduced; there are four second support wheels 445, one second rotation axis 443 corresponds to two second support wheels 445, the corresponding two second support wheels 445 are respectively installed at both ends of the second rotation axis 443 extending out of the second kidney passage 422, and the second support wheels 445 roll on the side walls of the second sinking groove 421.

When the adjustment is needed, the worker rotates the second threaded rod 441, the second threaded rod 441 drives the second mounting block 442 to move, the second rotating shaft 443, the second fixing frame 444, the workbench 3 and the second mounting block 442 move synchronously, and the second supporting wheel 445 rolls while the second rotating shaft 443 moves, so that the sliding adjustment of the workbench 3 is realized.

Referring to fig. 3 and 4, in consideration of the fact that slippage may occur between the first supporting wheel 435 and the side wall of the first sinking groove 411 and between the second supporting wheel 445 and the side wall of the second sinking groove 421, gear rings 451 are integrally formed on the outer walls of the first supporting wheel 435 and the second supporting wheel 445, racks 452 (see fig. 5) are integrally formed on the side wall of the first sinking groove 411 in contact with the first supporting wheel 435 and the side wall of the second sinking groove 421 in contact with the second supporting wheel 445, and the gear rings 451 are engaged with the racks 452, so that slippage does not occur when rolling.

Referring to fig. 4 and 5, an annular groove 453 having a triangular cross section is formed in the ring gear 451 along the circumferential direction thereof, a stopper belt 454 is integrally provided on the rack 452 along the length direction thereof to be engaged with the annular groove 453, and the stopper belt 454 restricts the rolling path of the ring gear 451, so that the possibility of lateral deviation when the first support wheel 435 and the second support wheel 445 roll can be greatly reduced, and the stability of the work table 3 can be improved.

Referring to fig. 3 and 4, after a period of use, dust particles may accumulate on the rack 452, and the ring gear 451 may jolt when rotated, affecting the stability of the table 3. Therefore, the first fixing frame 434 is fixedly provided with the dust suction pipes 46 aligned with the upper surface of the rack 452, the dust suction pipes 46 are connected to the dust collector, and one first fixing frame 434 is provided with two dust suction pipes 46, the two dust suction pipes 46 are respectively located at two sides of the rolling direction of the first supporting wheel 435, and when the moving directions are different, the two dust suction pipes 46 suck air according to the specific moving direction to suck away dust particles. Similarly, the second fixing frame 444 is also provided with the dust suction pipes 46, and the two aligned racks 452 are also provided, and are respectively located on both sides of the rolling direction of the second support wheel 445.

Referring to fig. 4, in order to reduce the wear of the gear ring 451 and the rack 452, a driving member 474 is disposed on the first fixing frame 434, the driving member 474 employs a third cylinder, the third cylinder is fixedly mounted on the first fixing frame 434, a piston rod of the third cylinder moves vertically, an extension rod 471 is fixedly disposed on the piston rod of the third cylinder, and a sponge wheel 473 soaked with lubricating oil is rotatably mounted on the extension rod 471. The piston rod of the third cylinder extends and retracts to drive the sponge wheel 473 to ascend and descend, so that the sponge wheel 473 is in contact with the gear ring 451, and the gear ring 451 is lubricated.

In order to supplement the lubricating fluid in the sponge wheel 473, an oil storage groove 475 is fixedly arranged on the sliding rod, the lubricating oil is contained in the oil storage groove 475, the oil storage groove 475 is positioned below the sponge wheel 473, the part of the lower end of the sponge wheel 473 is immersed in the lubricating oil in the oil storage groove 475, and the side, close to the first support wheel 435, of the sponge wheel 473 is in contact with the gear ring 451. Similarly, an extension rod 471, a sponge wheel 473, a driving member 474, and an oil reservoir 475 are also provided on the second fixing frame 444 to lubricate the gear ring 451 on the longitudinal adjustment frame 42.

Referring to fig. 2, the observation mechanism includes a bracket 5, the bracket 5 is L-shaped and is fixedly disposed on the transverse adjusting bracket 41, and the length of the horizontal side of the bracket 5 is greater than the length of the longitudinal adjusting bracket 42 exceeding the transverse adjusting bracket 41, so that the longitudinal adjusting bracket 42 does not touch the vertical side of the bracket 5 when sliding. A display screen 51 is fixedly arranged at the middle position of one end, far away from the transverse adjusting frame 41, of the horizontal edge of the support 5, a camera (not shown in the figure) which is used for shooting towards the welding position and is electrically connected with the display screen 51 is fixedly arranged on the laser 2, and a lamp 53 which irradiates towards the welding position is also fixedly arranged on the laser 2. The lamp 53 is used to illuminate the weld and the camera transmits the image to the display screen 51 for viewing by the operator.

Referring to fig. 2 and 6, at the same time, since the second threaded rod 441 moves along the lateral adjustment frame 41 together with the longitudinal adjustment frame 42, it is inconvenient for a worker to adjust. In order to facilitate the adjustment of the second threaded rod 441, a second worm gear 541 is fixedly arranged at one end of the second threaded rod 441, which penetrates through the longitudinal adjusting frame 42, the end of the second threaded rod 441, which penetrates through the longitudinal adjusting frame 42, is close to the display screen 51, the bracket 5 is rotatably provided with a rotating rod 55, the length direction of which is parallel to the sliding direction of the longitudinal adjusting frame 42, the length of the rotating rod 55 is greater than that of the transverse adjusting frame 41, the peripheral surface of the rotating rod 55 is integrally provided with a flange along the length direction thereof, a second worm sleeve 542 meshed with the second worm gear 541 is slidably sleeved on the rotating rod 55, and the second worm sleeve 542 is circumferentially fixed with the rotating rod 55. The rotating rod 55 rotates to drive the second worm sleeve 542 to rotate, the second worm sleeve 542 rotates to drive the second worm wheel 541 to rotate, and the second threaded rod 441 and the second worm wheel 541 rotate synchronously to realize the rotation of the second threaded rod 441. Meanwhile, a limiting sleeve 48 is fixedly arranged at one end of the longitudinal adjusting frame 42 close to the display screen 51, and the rotating rod 55 rotates to penetrate through the limiting sleeve 48, so that the matching between the second threaded rod 441 and the second worm gear 541 is stable.

Referring to fig. 6, in order to facilitate the rotation of the rotating rod 55, an operating rod 56 parallel to the rotating rod 55 is further disposed on the bracket 5, one end of the operating rod 56 is rotatably connected to the bracket 5, the operating rod 56 is in gear transmission connection with the rotating rod 55, and the other end of the operating rod 56 is located on one side of the display screen 51 and is fixedly provided with a rotating block 57. The rotating rod 55 can be driven to rotate by rotating the rotating block 57, the rotating block 57 is closer to the display screen 51, and the position deviation of electric welding can be timely adjusted when the position deviation is seen.

Referring to fig. 2, the worktable 3 has a square plate shape, the clamping mechanism includes a fixed frame 31, the fixed frame 31 is vertically installed on the worktable 3 and is located at one end close to the display screen 51, and one of the long sides of the fixed frame 31 is fixed on the worktable 3 and is parallel to the length direction of the transverse adjusting bracket 41.

Referring to fig. 2 and 7, each long side of the fixed frame 31 is provided with two moving seats 311 horizontally and slidably at an interval, the two moving seats 311 vertically corresponding to each other form a group, the two moving seats 311 vertically corresponding to each other are fixedly connected to form a vertical moving column 312, and the moving column 312 enables the two moving seats 311 connected to each other to move on the fixed frame 31 synchronously.

The fixed frame 31 is provided with a second driving assembly connected with the moving base 311, the second driving assembly comprises two second screws (not shown in the figure) and a second motor 322, the two second screws are respectively rotatably mounted on the two long sides of the fixed frame 31, and the length direction of the second screws is parallel to the length direction of the long sides of the fixed frame 31; the second screw has two opposite screw sections, and the two moving bases 311 on the long side of the same fixing frame 31 are respectively in threaded fit with the two screw sections, so that the second screw can drive the two moving bases 311 on the long side of the same fixing frame 31 to move relatively.

The two second screws penetrate through the fixed frame 31, the first linkage rod 313 is rotatably installed on the vertical wide side of the fixed frame 31, and two ends of the first linkage rod 313 are respectively meshed and connected with the penetrating ends of the two second screws through the first bevel gear 314, so that the two second screws can synchronously rotate. The second motor 322 is disposed on the vertical wide side of the fixed frame 31, and the output shaft of the second motor 322 is provided with a second bevel gear 315 engaged with the first bevel gear 314. The second motor 322 drives the two second screws to rotate through the engagement of the first bevel gear 314 and the second bevel gear 315, and the second screws drive the moving base 311 to move, so that the two moving columns 312 move.

Referring to fig. 2 and 7, the lifting block 33 is slidably disposed on the moving column 312 along the vertical direction, the fixed frame 31 is provided with a third driving assembly 34 connected to the two lifting blocks 33 and connected to the second motor 322, the third driving assembly 34 includes a third screw 341, a first worm sleeve 342, a first worm wheel 343, and a second link rod 344, two third screws 341 are rotatably mounted on the two corresponding moving seats 311, and the third screws 341 are parallel to the moving column 312 and are in threaded engagement with the lifting blocks 33; the number of the first worm gears 343 is two, and the first worm gears 343 and the third screw rods 341 are coaxially and fixedly mounted at the lower ends of the two third screw rods 341, respectively, and rotate synchronously; the first worm wheel 342 is rotatably mounted on two movable bases 311 on the long side of the lower part of the fixed frame 31, and the first worm wheel 342 is engaged with the first worm wheel 343, and the axial direction of the first worm wheel 342 is parallel to the longitudinal direction of the long side of the fixed frame 31.

Two ends of the second link rod 344 are rotatably mounted on two vertical side wide edges of the fixed frame 31, the second link rod 344 coaxially penetrates through the two first worm sleeves 342, and protrusions are also arranged on the peripheral side of the second link rod 344 along the length direction, so that the second link rod 344 and the first worm sleeves 342 are fixed in the peripheral direction and slide axially. One end of the second linkage rod 344, which is close to the second motor 322, penetrates through the fixed frame 31, a first gear 345 is fixedly installed at one end of the second linkage rod 344, which penetrates through the fixed frame 31, and a second gear 323, which is meshed with the first gear 345, is fixed on an output shaft of the second motor 322.

Referring to fig. 7, a second cylinder 317 is fixedly installed on the table 3, a piston rod of the second cylinder 317 extends in a direction parallel to a longitudinal direction of a long side of the fixed frame 31, and a second motor 322 is fixedly installed on the piston rod of the second cylinder 317. The second gear 323 and the second bevel gear 315 are installed on the output shaft of the second motor 322 at intervals, and the second gear 323 and the second bevel gear 315 are located between the first gear 345 and the first bevel gear 314, and the engagement of the second gear 323 and the first gear 345 on the second motor 322 and the engagement of the first bevel gear 314 and the second bevel gear 315 are controlled by the extension and contraction of the piston rod of the second cylinder 317. Chamfers are provided at both ends of the teeth of the first gear 345 and both ends of the teeth of the second gear 323 to facilitate the insertion of the teeth of the first gear 345 into the teeth of the second gear 323.

Referring to fig. 2 and 8, an L-shaped first clamping block 331 is fixedly arranged on the side of the lifting block 33 away from the display screen 51, the long side of the first clamping block 331 is fixed on the lifting block 33, and the short side of the first clamping block 331 faces to another first clamping block 331; the horizontal side wall of the lifting block 33 is provided with a second clamping block 332 in an L shape in a sliding manner, the second clamping block 332 is arranged on one side of the two lifting blocks 33, the sliding direction of the second clamping block 332 is parallel to the sliding direction of the workbench 3, the long side of the second clamping block 332 is in dovetail fit with the lifting block 33, and the short side of the second clamping block 332 faces the long side of the first clamping block 331 on the same lifting block 33.

The short side of the first clamping block 331 and the short side of the second clamping block 332 form a welding part clamping area, a first driving assembly 35 connected with the second clamping block 332 is arranged on the lifting block 33, the first driving assembly 35 comprises a first air cylinder 351 and a connecting block 352, the first air cylinder 351 is fixedly installed on one side, facing the display screen 51, of the lifting block 33, the expansion direction of a piston rod of the first air cylinder 351 is parallel to the sliding direction of the second clamping block 332, and the connecting block 352 connects the piston rod of the first air cylinder 351 and one end, close to the display screen 51, of the second clamping block 332. The piston rod of the first cylinder 351 stretches and retracts to drive the second clamping block 332 to slide, so that the butt welding piece is clamped. In order to increase the clamping force, rubber cushions 333 are fixed to both the short sides of the first clamping block 331 and the short sides of the second clamping block 332, so that the friction force is increased.

Referring to fig. 2, a fan 21 is also fixedly arranged on the outer wall of the laser 2, and the fan 21 blows to the welding position to play a role in cooling and cleaning dust; and the lamp 53 is located on the path of the blower 21 blowing toward the welding site, the temperature of the lamp 53 can be lowered, and the possibility that the life of the lamp 53 is reduced due to a high temperature for a long time is reduced.

In order to improve the cleanliness of the air blown by the fan 21, the laser 2 is further provided with a water tank 22, the water tank 22 comprises a bottom box 221 and a top cover 222, the bottom box 221 is fixed on the laser 2, the opening of the bottom box 221 faces upwards, and the bottom box 221 is filled with water; the top cover 222 is screwed on the bottom case 221 and covers and seals the opening of the bottom case 221. An air supply pipe 223 is connected to the top cover 222 and the air inlet of the fan 21, and an air inlet pipe 224 is further arranged on the top cover 222, and the air inlet pipe 224 extends to just below the water surface. The air of the blower 21 is drawn from the water tank 22, the air in the water tank 22 is replenished through the air intake pipe 224, and the water filters the introduced air while passing through the water.

The working principle of the embodiment is as follows:

when the device is used, a weldment is placed on the workbench 3, the second motor 322 drives the second screw rod to rotate through the second air cylinder 317, and the weldment is enabled to lean against the short edges of the two first clamping blocks 331; according to the height of the weldment, the second motor 322 drives the first gear 345 to rotate through the second cylinder 317, so that the third screw 341 rotates, and the lifting of the lifting block 33 is realized; then start first cylinder 351, first cylinder 351 drives second grip block 332 and makes second grip block 332 support tightly to the weldment, realizes the centre gripping of butt welding spare.

The first drive motor 436 is then activated to move the longitudinal adjustment bracket 42 and rotate the rotary block 57 to move the table 3 until the end of the edge of the weldment to be welded is directly below the laser 2, and welding can begin.

In the welding process, fan 21, lamp 53, display screen 51, camera, dust absorption pipe 46 all are in operating condition, and the staff is according to the welding position that display screen 51 saw, if there is the deviation, then rotates commentaries on classics piece 57 for workstation 3 removes, guarantees welding position's accuracy.

When lubricating oil needs to be added, the third cylinder drives the extension rod 471 to descend to the point that the sponge wheel 473 contacts the gear ring 451, and the sponge wheel 473 is driven by the gear ring 451 to rotate, so that the lubricating oil on the sponge wheel 473 is coated on the gear ring 451, and the purpose of adding the lubricating oil is achieved.

Example two:

a production process of a range hood comprises the following process steps:

s1: cutting a stainless steel raw material by using a cutting machine to obtain a raw material composite board;

s2: bending and punching the raw material composite board by using a punching machine to obtain a finished product composite board;

s3: firstly, preprocessing the welding surface of the combined plate, then combining the finished combined plate, welding the combined plate by using the laser spot welding machine in the first embodiment, and forming a primary welding seam at the welding position of the combined plate to obtain a semi-finished lampblack shell;

the pretreatment steps are as follows:

step b: and spraying a welding enhancer on the welding surface by using a high-pressure air spray gun, wherein the welding enhancer comprises 60% of an active agent, 20% of ferrotitanium powder, 20% of Cr, Ni and stainless steel mixed powder, and the mass ratio of the Cr powder to the Ni powder to the stainless steel powder is 1: 2: 3. The active agent comprises the following components in percentage by weight: 15% of sodium fluoride, 10% of calcium fluoride, 5% of silicon dioxide and 70% of acetone.

S4: polishing a primary welding line on the semi-finished product lampblack shell, and removing redundant waste materials on the welding line;

s5: observing the polished welding seam, and if a defective welding point on the welding seam is found, performing repair welding on the defective welding point on the polished welding seam by using the laser spot welding machine in the first embodiment to obtain a finished lampblack shell;

s7: and (5) carrying out aging test on the range hood, and packaging after the test is qualified.

The difference between examples 2 to 17 and example 1 is that the weld reinforcement agent comprises the following components in percentage by weight.

Examples 18-22 differ from example 1 in that the active agents are as follows in weight percent.

Examples	Sodium fluoride	Calcium fluoride	Silicon dioxide	Acetone (II)
					Example 18	13.75	8	5.75	72.5
Example 19	12.5	7	6.5	75
					Example 20	11.25	6	7.25	77.5
Example 21	10	5	8	80
					Example 22	11	9	5	75

Comparative example

The difference between the comparative example 1 and the example 1 is that the welding surface of the combined plate is not pretreated in the production process of the range hood;

detection method

And (3) testing the welding strength:

fixing one of the stainless steel plates welded in the embodiment 1 and the comparative example 1 by using a universal tensile machine, then pulling the other steel plate, gradually lifting the tensile force until the two steel plates are separated, and recording the tensile force at the moment of separation.

Examples	Tensile Strength (KN)
		Example 1	135.6
Comparative example 1	96

And (4) conclusion: as can be seen from the above detection data, the welding tensile strength between the two steel plates welded by the process of the present invention in example 1 is significantly higher than that in comparative example 1, so that it can be seen that the pretreatment of the welding surface during the initial welding in the present invention has a significant effect of improving the welding strength of the steel plates.

The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.

Claims

1. A laser spot welder, comprising a frame (1), characterized in that: the laser device comprises a rack (1) and is characterized in that a laser device (2), an observation mechanism and a moving mechanism are arranged on the rack (1), a workbench (3) is arranged on the moving mechanism, a clamping mechanism is arranged on the workbench (3), the clamping mechanism comprises a fixed frame (31) vertically installed on the workbench (3), two moving seats (311) are horizontally arranged on the fixed frame (31) in a sliding mode at intervals, and a second driving assembly which is connected with the two moving seats (311) and can drive the two moving seats (311) to move relatively is arranged on the fixed frame (31); the moving mechanism comprises a transverse adjusting frame (41) arranged on the rack (1), a longitudinal adjusting frame (42) is arranged on the transverse adjusting frame (41) in a sliding mode, a fourth driving assembly connected with the longitudinal adjusting frame (42) is arranged on the transverse adjusting frame (41), the workbench (3) is arranged on the longitudinal adjusting frame (42) in a sliding mode, and a fifth driving assembly connected with the workbench (3) is arranged on the longitudinal adjusting frame (42);

horizontal alignment jig (41) are provided with first heavy groove (411) along length direction's both sides are sunken, first waist shape passageway (412) have been seted up to the tank bottom of first heavy groove (411), the fourth drive assembly is installed including rotating horizontal alignment jig (41) go up and axis direction with the parallel first threaded rod of length direction of horizontal alignment jig (41), two at least screws are installed first installation piece (432) on the first threaded rod, install on first installation piece (432) and both ends stretch out first rotation axis (433) of first waist shape passageway (412), install vertical alignment jig (42) lower surface and with first mount (434), the rotation of first rotation axis (433) rotation connection are installed on first rotation axis (433) and on the lateral wall of first heavy groove (411) rolling first supporting wheel (435), A first driving motor (436) mounted on the transverse adjusting frame (41) and connected with the first threaded rod;

the longitudinal adjusting frame (42) is concavely provided with second sunk grooves (421) along two sides of the length direction, a second kidney-shaped channel (422) is formed in the bottom of each second sunk groove (421), the fifth driving component comprises a second threaded rod (441) which is rotatably installed on the longitudinal adjusting frame (42) and has the axis direction parallel to the length direction of the longitudinal adjusting frame (42), at least two second installation blocks (442) which are installed on the second threaded rod (441) in a threaded manner, a second rotating shaft (443) which is installed on the second installation blocks (442) and has two ends extending out of the second kidney-shaped channel (422), a second fixed frame (444) which is installed on the lower surface of the workbench (3) and is rotatably connected with the second rotating shaft (443), and a second supporting wheel (445) which is rotatably installed on the second rotating shaft (443) and rolls on the side wall of the second sunk groove (421), one end of the second threaded rod (441) extends out of the longitudinal adjusting frame (42);

the observation mechanism comprises an L-shaped support (5) arranged on the transverse adjusting frame (41), a display screen (51) is arranged on the support (5), the laser (2) is provided with a camera which is used for shooting a welding position and is electrically connected with the display screen (51), and the laser (2) is also provided with a lamp (53) which irradiates the welding position;

a second worm wheel (541) is arranged at one end, penetrating out of the longitudinal adjusting frame (42), of the second threaded rod (441), the bracket (5) is rotatably provided with a rotating rod (55) with the length direction parallel to the sliding direction of the longitudinal adjusting frame (42), a second worm sleeve (542) meshed with the second worm wheel (541) is slidably sleeved on the rotating rod (55), and the second worm sleeve (542) and the rotating rod (55) are circumferentially fixed;

the support (5) is further provided with an operating rod (56) parallel to the rotating rod (55), one end of the operating rod (56) is rotatably connected to the support (5), the operating rod (56) is in transmission connection with the rotating rod (55) through a gear, and the other end of the operating rod (56) is located on one side of the display screen (51) and is provided with a rotating block (57);

the second driving assembly comprises a second screw rod which is rotatably installed on the fixed frame (31) and is in threaded fit with the two moving seats (311), and a second motor (322) which is installed on the fixed frame (31) and is connected with one end of the second screw rod, the second screw rod is provided with two reverse threaded sections, and the two moving seats (311) are in threaded fit with the two threaded sections respectively;

the fixed frame (31) is in a rectangular frame shape, two moving seats (311) are arranged on two horizontal long edges of the fixed frame, and the two moving seats (311) which correspond to each other vertically are connected with a vertical moving column (312); two long edges of the fixed frame (31) are respectively and rotatably provided with a second screw, one end of the fixed frame (31) at the same side of the second screws penetrates out of the fixed frame, a first linkage rod (313) is rotatably arranged on the vertical wide edge of the fixed frame (31) at one side of the fixed frame (31) where the second screws penetrate out, two ends of the first linkage rod (313) are respectively meshed and connected with one end of the two penetrating second screws through a first bevel gear (314), and the second motor (322) is connected with one end of any penetrating second screw; the lifting block (33) is arranged on the moving column (312) in a sliding mode along the vertical direction, a first clamping block (331) is installed on the lifting block (33), a second clamping block (332) corresponding to the first clamping block (331) is arranged on the lifting block (33) in a sliding mode, a space for clamping a welding part is formed on one side, opposite to the first clamping block (331) and the second clamping block (332), of the first clamping block (331) and the second clamping block (332), a first driving assembly (35) connected with the second clamping block (332) is arranged on the lifting block (33), and a third driving assembly (34) connected with the two lifting blocks (33) and the second motor (322) is arranged on the fixing frame (31); the first driving assembly (35) comprises a first air cylinder (351) installed on the lifting block (33), and a connecting block (352) installed on a piston rod of the first air cylinder (351) and connected with the first clamping block (331), and the expansion and contraction direction of the piston rod of the first air cylinder (351) is parallel to the sliding direction of the second clamping block (332);

a rack (452) is arranged on the side wall of the first sinking groove (411) which is in contact with the first supporting wheel (435), and a gear ring (451) meshed with the rack (452) is arranged on the outer wall of the first supporting wheel (435); the gear ring (451) is provided with an annular groove (453) with a triangular section along the circumferential direction, and the rack (452) is provided with a limit belt (454) matched with the annular groove (453) along the length direction;

the first fixing frames (434) are provided with dust suction pipes (46) aligned with the upper surfaces of the racks (452), two dust suction pipes (46) are arranged on one first fixing frame (434), and the two dust suction pipes (46) are respectively positioned at two sides of the first supporting wheel (435);

a driving piece (474) is arranged on the first fixing frame (434), the driving piece (474) is connected with an extension rod (471), a sponge wheel (473) soaked with lubricating oil is rotatably installed on the extension rod (471), and the driving piece (474) can drive the extension rod (471) to lift;

the extension rod (471) is further provided with an oil storage tank (475), lubricating oil is contained in the oil storage tank (475), the oil storage tank (475) is located below the sponge wheel (473), and the sponge wheel (473) is partially immersed in the lubricating oil in the oil storage tank (475).

2. A laser spot welder according to claim 1, characterized in that: the second motor (322) is arranged on the fixed frame (31) in a sliding manner along the axial direction of the second screw rod, and the fixed frame (31) is provided with a second air cylinder (317) connected with the second motor (322);

the third driving assembly (34) comprises a third screw (341) with two ends rotatably mounted on the two corresponding moving seats (311) and parallel to the moving column (312) and in threaded fit with the lifting block (33), two second worm sleeves (342) rotatably mounted on the same long edge of the fixed frame (31), a first worm wheel (343) coaxially mounted on the third screw (341) and meshed with the first worm sleeve (342), and a second coupling rod (344) with two ends rotatably connected to two wide edges of the fixed frame (31) and slidably passing through the two first worm sleeves (342), the second link rod (344) is fixed to the first worm housing (342) in the circumferential direction and slides axially, one end of the second linkage rod (344) penetrates through the fixed frame (31) and is provided with a first gear (345);

a second gear (323) meshed with the first gear (345) is coaxially installed on an output shaft of the second motor (322), the teeth of the first gear (345) and the teeth of the second gear (323) are provided with chamfers, a second bevel gear (315) meshed with the first bevel gear (314) is also coaxially installed on the output shaft of the second motor (322), and when the second cylinder (317) drives the second motor (322) to slide, the second bevel gear (315) can be meshed with the first bevel gear (314) or the first gear (345) is meshed with the second gear (323).

3. A production process of a range hood is characterized by comprising the following process steps:

s3: combining the finished combination boards, and welding the combination boards by a laser spot welding machine according to any one of claims 1-2 to form a primary welding line to obtain a semi-finished lampblack shell; the welding surface of the combined plate is pretreated before welding;

s5: observing the polished welding line, and performing repair welding on the defective welding point on the polished welding line by using the laser spot welding machine according to any one of claims 1-2 to obtain a finished lampblack shell;