Numerical control lathe special for machining thin-walled workpieces

Abstract

The special numerical control lathe comprises a lathe body, a spindle box, a Z-axis driving mechanism, an X1-axis driving mechanism, an X2-axis driving mechanism, a sliding saddle, a tailstock, a tailstock driving mechanism, an auxiliary tool rest, a material supporting frame and a protection structure, a cooling chip removal system is installed on the front side of the lathe body, and a front tool rest, a rear tool rest and a follow rest are installed on the sliding saddle. The X1-axis driving mechanism and the X2-axis driving mechanism are installed on the sliding saddle in parallel, an outer circular knife is installed on the front knife rest, an inner hole knife is installed on the rear knife rest, a plurality of clamping units are arranged on the follow rest, a main shaft is arranged in the main shaft box, a sleeve is installed on the tailstock, the sleeve and the main shaft are coaxially arranged, and a chuck is installed at the rear end of the main shaft. The material supporting frame is installed on one side of the spindle box, and a plurality of material receiving arms are arranged on the material supporting frame. The numerical control lathe can synchronously machine the inner surface and the outer surface of the thin-wall part, one-time machining of the thin-wall part can be completed through one-time clamping, the coaxiality of the thin-wall part is guaranteed, and the problem of machining deformation of the thin-wall part is effectively solved.

Description

Technical Field

[0001] The invention belongs to the technical field of CNC lathes, and in particular relates to a special CNC lathe for processing thin-walled parts. Background Art

[0002] At present, there are no standard CNC lathe products for processing thin-walled parts in the market. Most of them are special-purpose machine tools, which belong to a relatively niche type of machine tools. Due to their high professionalism and specialization, general machine tool companies do not have the ability to develop, design, and produce them. The processing of slender thin-walled parts is still at the stage of fully manual loading and unloading, multiple machine tools and multiple processes.

[0003] Thin-walled parts are difficult to clamp and are easily deformed. The inner hole of thin-walled parts is difficult to process, especially the long inner hole of slender thin-walled parts. During the processing, problems such as tool vibration and short tool arm often occur. The most commonly used method for processing thin-walled parts is U-turn machining, that is, machining half of the part and then clamping the other half to solve the problem of short tool arm. However, the two clampings make it difficult to ensure the coaxiality and processing rhythm of the inner hole of the thin-walled parts, resulting in a high scrap rate for thin-walled parts. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a special CNC lathe for processing thin-walled parts in view of the shortcomings of the prior art, which can realize the synchronous processing of the inner and outer surfaces of the thin-walled parts, complete the one-time processing of the thin-walled parts with one clamping, ensure the coaxiality of the thin-walled parts, and effectively solve the problem of deformation of the thin-walled parts during processing.

[0005] The technical solution adopted by the present invention to solve the above technical problems is: a special CNC lathe for processing thin-walled parts, including a bed, a spindle box, a Z-axis drive mechanism, an X1-axis drive mechanism, an X2-axis drive mechanism, a saddle, a tailstock, a tailstock drive mechanism, an auxiliary tool holder, a support rack and a protective structure. A cooling and chip removal system is installed on the front side of the bed. The spindle box, Z-axis drive mechanism, saddle, tailstock and tailstock drive mechanism are respectively installed on the bed. The protective structure is arranged on the outside of the bed. The Z-axis drive mechanism is used to drive the saddle to move in the Z direction. A front tool holder, a rear tool holder and a follower tool holder are installed on the saddle. The X1-axis drive mechanism and the X2-axis drive mechanism are installed in parallel on the saddle. The X1-axis drive mechanism is used to drive the front tool holder to move in the X direction. The X2-axis drive mechanism is used to drive the rear tool holder to move in the X direction. An external circular cutter for machining the outer circle and end face of the workpiece is installed on the tool holder, an internal hole cutter for machining the inner hole of the workpiece is installed on the rear tool holder, the follower tool holder is close to the front end face of the front tool holder, a plurality of clamping units are arranged on the follower tool holder, and the plurality of clamping units are used to clamp the outer circle of the workpiece, a main shaft is arranged in the main spindle box, a sleeve is installed on the tail stock, the sleeve is coaxially arranged with the main spindle, a chuck is installed at the rear end of the main spindle, the chuck is used to clamp the front end of the workpiece, the sleeve is used to tighten the rear end face of the workpiece, the tail stock driving mechanism is used to drive the tail stock to move in the Z direction, the support frame is installed on one side of the main spindle box, a plurality of material receiving arms are arranged on the support frame, the auxiliary tool holder is installed at the bottom of the main spindle box, a tool for cutting the workpiece is installed on the auxiliary tool holder, and the support frame is used to support the workpiece after cutting.

[0006] The CNC lathe of the present invention can realize synchronous processing of the inner and outer surfaces of thin-walled parts, and can complete one-time processing of thin-walled parts with one clamping, thereby ensuring the coaxiality of thin-walled parts, meeting the beat requirements of workpiece production, and having a high product qualification rate, and is particularly suitable for processing slender thin-walled parts.

[0007] A double tool rest structure consisting of a front tool rest and a rear tool rest is installed on the slide saddle of the numerically controlled lathe of the present invention. The front tool rest and the rear tool rest are driven by independent X1-axis driving mechanisms and X2-axis driving mechanisms, respectively. The functions of the front tool rest and the rear tool rest are different. The movement of the slide saddle in the Z direction is driven by the Z-axis driving mechanism, which can realize the synchronous movement of the front tool rest and the rear tool rest, and achieve the synchronous processing of the inner and outer surfaces of the workpiece by the external circular cutter and the internal hole cutter to the greatest extent. The processing is convenient and efficient, and most of the cutting resistance generated by the processing is offset, which is an important factor in realizing the non-deformation of the processing of thin-walled parts, so that the problem of deformation of thin-walled parts during processing can be effectively solved. In addition, the X1-axis driving mechanism and the X2-axis driving mechanism are separated, which can ensure that the processing thickness between the front tool rest and the rear tool rest meets the requirements of different workpiece sizes. A follower rest is also installed on the saddle to clamp the outer circle of the workpiece. The follower rest is close to the front end face of the front tool holder and will not cause over-positioning problems with the spindle and tailstock. The follower rest is close to the external cylindrical cutter on the front tool holder and can absorb the vibration generated during workpiece processing, effectively reducing the deformation of the workpiece caused by lack of support.

[0008] After the thin-walled parts are clamped, the front end of the workpiece is clamped by the chuck on the spindle, and the rear end of the workpiece is tightened by the sleeve. The inner hole cutter on the rear tool holder can pass through the sleeve and enter the workpiece from the rear end to process the inner hole of the workpiece. At the same time, the outer circle cutter on the front tool holder can synchronously process the outer surface of the workpiece, thereby realizing one-time processing of thin-walled parts, and the coaxiality and beat of workpiece processing are guaranteed, without multiple clamping and turning to process the workpiece. After the workpiece is processed, the tool installed on the auxiliary tool holder can directly cut off the front end of the finished workpiece, and the finished workpiece after cutting is supported by the support rack in place in advance, reducing the processing procedures for the finished workpiece and saving processing beat.

[0009] Preferably, the guide rail surface of the bed is arranged with an inclination of 45°, and a first Z axis line rail and a second Z axis line rail are installed on the guide rail surface in parallel with each other. The saddle is slidably mounted on the first Z axis line rail, and the tailstock is slidably mounted on the second Z axis line rail.

[0010] Preferably, the Z-axis driving mechanism, the X1-axis driving mechanism, and the X2-axis driving mechanism are respectively screw-driven structures.

[0011] Preferably, the tailstock includes a tailstock body, a first slider is installed at the bottom of the tailstock body, the first slider is slidably connected to the second Z axis rail, the tailstock drive mechanism includes a first cylinder, the first cylinder is installed on the bed, the piston rod of the first cylinder is connected to the tailstock body, a mounting tube is provided on the upper side of the tailstock body, and the sleeve is rotatably mounted on the inner side of the mounting tube through a bearing. Different from the design of sleeve movement in the hydraulic tailstock of an ordinary CNC lathe, the present invention simplifies the structure of the tailstock and adopts a movable tailstock with a large-aperture hollow structure, which facilitates the inner hole cutter on the rear tool holder to pass through the inner side of the sleeve installed on the tailstock and enter the interior of the workpiece. The sleeve is connected to the mounting tube through a bearing to ensure that the sleeve can rotate synchronously with the workpiece while pressing against the rear end face of the workpiece, thereby ensuring the machining accuracy of the workpiece. In addition, the tailstock body is driven by the first cylinder, which has a simple and reliable structure. Since the present invention is a special CNC lathe and the size of the workpiece to be processed is relatively fixed, the stroke of the first cylinder is smaller and the corresponding second Z-axis line is shorter, which not only reduces the cost but also allows the first cylinder to fully exert its Z-direction driving function.

[0012] Preferably, the inner circular surface of the front end of the sleeve is provided with a circle of sawtooth chamfer, and the rear end of the workpiece is pre-processed with a chamfered portion, and the sawtooth chamfer matches the chamfer size of the chamfered portion. When the sleeve is pressed against the rear end surface of the workpiece, the sawtooth chamfer fits with the chamfered portion. The sawtooth chamfer fits with the chamfered portion, and the friction between the two is large, which can ensure that the sleeve and the workpiece are tightly combined and will not rotate relative to each other. The Z-axis thickness dimension of the entire tailstock is small, which does not affect the length of the inner hole cutter on the rear tool holder.

[0013] Preferably, the sleeve is interference fit with the inner ring of the bearing, the front end and the rear end of the inner ring of the bearing are respectively pressed by the first front pressure cover and the first rear pressure cover, the first rear pressure cover is fixed to the sleeve, the front end and the rear end of the outer ring of the bearing are respectively pressed by the second front pressure cover and the second rear pressure cover, the second rear pressure cover is fixed to the mounting tube, a third front pressure cover is fixed to the front side of the second front pressure cover, sealing rings are respectively arranged between the second front pressure cover and the mounting tube, between the second rear pressure cover and the mounting tube, and between the first rear pressure cover and the sleeve, the third front pressure cover, the second front pressure cover, the sleeve and the first front pressure cover form a first labyrinth gap, the first rear pressure cover and the second rear pressure cover form a second labyrinth gap, the first labyrinth gap and the second labyrinth gap are respectively connected to the outside atmosphere, and water throwing troughs are respectively arranged in the first labyrinth gap and the second labyrinth gap. The designs of the first front pressure cover, the first rear pressure cover, the second front pressure cover, the second rear pressure cover, the third front pressure cover, the first labyrinth gap, the second labyrinth gap and the water sluice can effectively prevent coolant from entering the bearing and extend the service life of the bearing.

[0014] Preferably, the tool rest comprises a frame, an arc hole is provided on the inner side of the frame, a notch is provided on the bottom of the frame, the notch is communicated with the arc hole, the upper part of the tailstock and the orthographic projection of the chuck in the Z direction fall on the inner side of the frame respectively, the number of the clamping units is three, the three clamping units are arranged at intervals along the circumference of the arc hole, each clamping unit comprises a second cylinder, a roller made of polyurethane is connected to the piston rod of the second cylinder, each roller extends into the arc hole, the three rollers are used to clamp the outer circle of the workpiece, the air pipes of the three second cylinders are respectively connected to a main air pipe and controlled by an on-off valve, and the angle between the piston rods of two adjacent second cylinders is 120°. The clamping force is provided by three independent second cylinders, and the outer circle of the workpiece is clamped by three rollers made of polyurethane, the rollers are easy to install, the replacement cost is low, and the rollers have moderate hardness and are in direct contact with the workpiece without damaging the machining surface of the workpiece. During the workpiece processing, due to the influence of cutting force, the three second cylinders will fine-tune the stroke of the piston rod to varying degrees, realizing the adaptive adjustment function, so as to achieve the purpose of both assisting in supporting the workpiece and not damaging the workpiece processing surface. If the roller becomes smaller in size due to wear after use, the second cylinder will automatically supplement the stroke in a progressive manner. Since the frame adopts a semi-enclosed structure, the upper part of the tailstock and the positive projection of the chuck in the Z direction fall on the inner side of the frame respectively, so that when the tool rest moves in the Z direction with the saddle, the tool rest can cross the tailstock and the chuck, ensuring that the external cylindrical cutter can move the full stroke without being affected by the tool rest.

[0015] Preferably, the support frame includes a first base, a second base, a third cylinder, a fourth cylinder and a linear rail, the first base is installed on one side of the spindle box, the third cylinder and the linear rail are uprightly installed on the first base, the piston rod of the third cylinder is connected to a second slider, the second slider is slidably connected to the linear rail, the second base is fixed to the front end of the second slider, the fourth cylinder is uprightly installed on the second base, the piston rod of the fourth cylinder is connected to a cam via a crank, the cam is connected to a horizontally arranged transmission shaft via a key, the transmission shaft crosses the second slider, a guide sleeve is installed between the transmission shaft and the second slider, two material receiving arms are connected in series on the transmission shaft, the bottom end of each material receiving arm is connected to the transmission shaft through a sleeve, the sleeve is fixed to the transmission shaft through a top screw, and the top of each material receiving arm is fixed with an arc-shaped support piece with an opening facing upward. The receiving arm of the above-mentioned material support rack can rotate or move up and down around the center line of the transmission shaft. When receiving materials, the receiving arm can be rotated to the bottom of the workpiece, and can be far away from the processing area when the spindle is processed, so as to reduce interference with other components and have minimal impact on the Z-axis stroke. When the above-mentioned material support rack is working, the first cylinder drives the receiving arm, the transmission shaft, the second base, the fourth cylinder, etc. to move up and down as a whole, so as to ensure that the processing area is as large as possible when the workpiece is processed; the second cylinder transmits power to the cam through the crank, and the cam rotates to drive the transmission shaft to rotate, and the transmission shaft drives the receiving arm to rotate. When receiving materials, the receiving arm rotates to the bottom of the workpiece, and the rest of the time it rotates to the side of the spindle, and is pushed to the lowest position away from the spindle by the first cylinder to avoid interfering with the spindle. In addition, by loosening the top screw, the position of the receiving arm on the transmission shaft can be adjusted.

[0016] Preferably, the spindle is a hollow spindle, the front end of the spindle is close to the inlet of the chip conveyor of the cooling chip removal system, and when the chuck clamps the front end of the workpiece, the front end of the workpiece extends into the inner hole of the spindle. The hollow large-aperture spindle can ensure that when machining the inner hole of the workpiece, the workpiece can enter the inside of the spindle, and the chips generated by machining can be flushed from the inner hole of the workpiece into the front end of the spindle and enter the chip conveyor, thereby solving the problem of discharging chips generated during the machining of the inner hole of the workpiece.

[0017] Compared with the prior art, the present invention has the following advantages: the CNC lathe of the present invention can realize synchronous processing of the inner and outer surfaces of thin-walled parts, and can complete the one-time processing of thin-walled parts with one clamping, thereby ensuring the coaxiality of thin-walled parts, effectively solving the problem of processing deformation of thin-walled parts, meeting the rhythm requirements of workpiece production, and having a high product qualification rate, and is particularly suitable for the processing of slender thin-walled parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is an appearance diagram of a CNC lathe in the embodiment;

[0019] Figure 2 This is an appearance diagram of a CNC lathe in an embodiment after removing the protective structure;

[0020] Figure 3 for Figure 2 Enlarged view of point A in the middle;

[0021] Figure 4 The appearance diagram of the saddle and the components installed on the saddle in the embodiment;

[0022] Figure 5 is a perspective view of a tool rest in the embodiment;

[0023] Figure 6 This is the appearance diagram of the tailstock in the embodiment;

[0024] Figure 7 A longitudinal sectional view of the upper portion of the tailstock in the embodiment;

[0025] Figure 8 for Figure 7 Enlarged view of point B in the middle;

[0026] Fig. 9 This is an appearance diagram of the bracket in the embodiment;

[0027] Fig.10 A longitudinal sectional view of the bracket in the embodiment;

[0028] Fig.11 for Fig.10 Enlarged view of point C in the middle;

[0029] The specific reference numerals in the figure are as follows:

[0030] 1-bed, 11-protection structure, 12-cooling and chip removal system, 13-first Z axis rail, 14-second Z axis rail, 15-chip conveyor, 2-spindle box, 21-chuck, 31-Z axis drive mechanism, 32-X1 axis drive mechanism, 33-X2 axis drive mechanism, 4-saddle, 41-front tool holder, 42-rear tool holder, 43-following tool holder, 431-frame, 432-arc hole, 433-notch, 434-second cylinder, 435-roller, 436-main air pipe, 44-external circular knife, 45-inner hole knife, 5-tailstock, 51-tailstock drive mechanism, 52-sleeve, 521-serrated chamfer, 53-tailstock body, 54-first slider, 55-first Cylinder, 56-mounting cylinder, 57-bearing, 581-first front pressure cover, 582-first rear pressure cover, 583-second front pressure cover, 584-second rear pressure cover, 585-third front pressure cover, 586-sealing ring, 587-first labyrinth gap, 588-second labyrinth gap, 589-water throwing trough, 6-auxiliary tool holder, 61-tool, 7-support rack, 71-material receiving arm, 711-arc support plate, 72-second base, 73-third cylinder, 74-fourth cylinder, 75-linear rail, 76-second slider, 77-crank, 78-cam, 79-sleeve, 70-transmission shaft, 701-key, 702-guide sleeve, 8-workpiece, 81-chamfering part. DETAILED DESCRIPTION

[0031] The present invention is further described in detail below in conjunction with the embodiments of the drawings. The devices, components or structures not limited in the present invention all adopt conventional technical means in the art.

[0032] Embodiment: A CNC lathe specially used for processing thin-walled parts, such as Figure 1 to Figure 3 As shown, it includes a bed 1, a spindle box 2, a Z-axis drive mechanism 31, an X1-axis drive mechanism 32, an X2-axis drive mechanism 33, a saddle 4, a tailstock 5, a tailstock drive mechanism 51, an auxiliary tool rest 6, a support frame 7 and a protective structure 11. The Z-axis drive mechanism 31, the X1-axis drive mechanism 32, and the X2-axis drive mechanism 33 are respectively screw drive structures. A cooling and chip removal system 12 is installed on the front side of the bed 1. The spindle box 2, the Z-axis drive mechanism 31, the saddle 4, the tailstock 5 and the tailstock drive mechanism 51 are respectively installed on the bed 1. The protective structure 11 is arranged on the outside of the bed 1. The Z-axis drive mechanism 31 is used to drive the saddle 4 to move in the Z direction, as shown in FIG. Figure 4As shown, the slide saddle 4 is equipped with a front tool rest 41, a rear tool rest 42 and a follower tool rest 43, the X1 axis driving mechanism 32 and the X2 axis driving mechanism 33 are installed in parallel on the slide saddle 4, the X1 axis driving mechanism 32 is used to drive the front tool rest 41 to move in the X direction, the X2 axis driving mechanism 33 is used to drive the rear tool rest 42 to move in the X direction, the front tool rest 41 is equipped with an external circular cutter 44 for machining the outer circle and end surface of the workpiece 8, the rear tool rest 42 is equipped with an internal hole cutter 45 for machining the inner hole of the workpiece 8, the follower tool rest 43 is close to the front end surface of the front tool rest 41, and three clamping units are arranged on the follower tool rest 43, and the three clamping units are used to clamp the outer circle of the workpiece 8, and a hollow spindle (not shown in the figure) is arranged in the spindle box 2. The front end of the spindle is close to the entrance of the chip conveyor 15 of the cooling and chip removal system 12. A sleeve 52 is installed on the tailstock 5. The sleeve 52 is coaxially arranged with the spindle. A chuck 22 is installed at the rear end of the spindle. The chuck 22 is used to clamp the front end of the workpiece 8. The sleeve 52 is used to tighten the rear end surface of the workpiece 8. When the chuck 22 clamps the front end of the workpiece 8, the front end of the workpiece 8 extends into the inner hole of the spindle. The tailstock drive mechanism 51 is used to drive the tailstock 5 to move in the Z direction. The support frame 7 is installed on one side of the spindle box 2. Two material receiving arms 71 are provided on the support frame 7. The auxiliary tool holder 6 is installed at the bottom of the spindle box 2. A tool 61 for cutting the workpiece 8 is installed on the auxiliary tool holder 6. The support frame 7 is used to support the workpiece 8 after cutting.

[0033] In this embodiment, the bed 1 adopts a casting structure, and the internal structure of the casting is optimized through finite element soft analysis. The guide rail surface of the bed 1 is arranged at an angle of 45 degrees, and a first Z axis rail 13 and a second Z axis rail 14 are installed on the guide rail surface in parallel with each other. The saddle 4 is slidably installed on the first Z axis rail 13, and the tailstock 5 is slidably installed on the second Z axis rail 14.

[0034] In this embodiment, Figure 6 to Figure 8 As shown, the tailstock 5 includes a tailstock body 53, a first slider 54 is installed at the bottom of the tailstock body 53, and the first slider 54 is slidably connected to the second Z axis rail 14. The tailstock drive mechanism 51 includes a first cylinder 55, which is installed on the bed 1. The piston rod of the first cylinder 55 is connected to the tailstock body 53. A mounting cylinder 56 is provided on the upper side of the tailstock body 53, and a sleeve 52 is rotatably mounted on the inner side of the mounting cylinder 56 through a bearing 57; the inner circular surface of the front end of the sleeve 52 is provided with a circle of serrated chamfer 521, and the rear end of the workpiece 8 is pre-processed with a chamfered portion 81, and the serrated chamfer 521 matches the chamfer size of the chamfered portion 81. When the sleeve 52 is pressed against the rear end surface of the workpiece 8, the serrated chamfer 521 fits with the chamfered portion 81.

[0035] In this embodiment, the sleeve 52 and the inner ring of the bearing 57 are interference fit, the front end and the rear end of the inner ring of the bearing 57 are respectively pressed by the first front pressure cover 581 and the first rear pressure cover 582, the first rear pressure cover 582 is fixed to the sleeve 52, the front end and the rear end of the outer ring of the bearing 57 are respectively pressed by the second front pressure cover 583 and the second rear pressure cover 584, the second rear pressure cover 584 is fixed to the installation cylinder 56, the front side of the second front pressure cover 583 is fixed with the third front pressure cover 585, the second front pressure cover 583 and the installation cylinder 56, the second rear pressure cover 584 is fixed with the third front pressure cover 586, and the second front pressure cover 583 and the installation cylinder 56 are fixed with the third front pressure cover 587. Sealing rings 586 are respectively arranged between the cover 584 and the mounting tube 56 and between the first rear pressure cover 582 and the sleeve 52. The third front pressure cover 585, the second front pressure cover 583, the sleeve 52 and the first front pressure cover 581 form a first labyrinth gap 587. The first rear pressure cover 582 and the second rear pressure cover 584 form a second labyrinth gap 588. The first labyrinth gap 587 and the second labyrinth gap 588 are respectively connected to the outside atmosphere. Water troughs 589 are respectively arranged in the first labyrinth gap 587 and the second labyrinth gap 588.

[0036] In this embodiment, Figure 5 As shown, the tool rest 43 includes a frame body 431, which is a welded structure. An arc hole 432 is provided on the inner side of the frame body 431, and a notch 433 is provided on the bottom of the frame body 431. The notch 433 is connected to the arc hole 432. The upper part of the tailstock 5 and the orthographic projection of the chuck 22 in the Z direction fall on the inner side of the frame body 431 respectively. Three clamping units are arranged at intervals along the circumference of the arc hole 432. Each clamping unit includes a second cylinder 434. A roller 435 made of polyurethane is connected to the piston rod of the second cylinder 434. Each roller 435 extends into the arc hole 432. The three rollers 435 are used to clamp the outer circle of the workpiece 8. The air pipes of the three second cylinders 434 are respectively connected to a main air pipe 436 and controlled by an on-off valve (not shown in the figure). The angle between the piston rods of two adjacent second cylinders 434 is 120°. The main air pipe 436 is also installed in the frame body 431. The overall appearance of the tool rest 43 is neat and tidy, no pipeline is exposed, and maintenance and adjustment are convenient.

[0037] In this embodiment, Figures 9 to 11As shown, the support frame 7 includes a first base 71, a second base 72, a third cylinder 73, a fourth cylinder 74 and a linear rail 75. The first base 71 is installed on one side of the spindle box 2, the third cylinder 73 and the linear rail 75 are vertically installed on the first base 71, the piston rod of the third cylinder 73 is connected to a second slider 76, the second slider 76 is slidably connected to the linear rail 75, the second base 72 is fixed to the front end of the second slider 76, the fourth cylinder 74 is upright on the second base 72, and the fourth The piston rod of the cylinder 74 is connected to a cam 78 via a crank 77, the cam 78 is connected to a horizontally arranged transmission shaft 70 via a key 701, the transmission shaft 70 crosses the second slider 76, a guide sleeve 702 is installed between the transmission shaft 70 and the second slider 76, two material receiving arms 71 are connected in series on the transmission shaft 70, the bottom end of each material receiving arm 71 is connected to the transmission shaft 70 through a shaft sleeve 79, the shaft sleeve 79 is fixed to the transmission shaft 70 through a top screw, and an arc-shaped support plate 711 with an opening facing upward is fixed to the top of each material receiving arm 71.

[0038] The CNC lathe in this embodiment also includes the lubrication system, hydraulic system, electrical system, etc. used in conventional CNC lathes, all of which adopt existing technologies and will not be described in detail here.

[0039] After the thin-walled part is clamped, the front end of the workpiece 8 is clamped by the chuck 22 on the spindle, and the rear end face of the workpiece 8 is pressed by the sleeve 52. The inner hole cutter 45 on the rear tool holder 42 can pass through the sleeve 52 and enter the interior of the workpiece 8 from the rear end of the workpiece 8 to process the inner hole of the workpiece 8. At the same time, the outer circle cutter 44 on the front tool holder 41 can synchronously process the outer surface of the workpiece 8, thereby realizing one-time processing of the thin-walled part, and the coaxiality and beat of the workpiece 8 processing are guaranteed, without multiple clamping and turning to process the workpiece 8. After the workpiece 8 is processed, the tool 61 installed on the auxiliary tool holder 6 can directly cut off the front end of the processed workpiece 8. The cut workpiece 8 is supported by the support rack 7 in place in advance, reducing the processing steps of the workpiece 8 and saving the processing beat.

[0040] The above-mentioned CNC lathe can realize synchronous processing of the inner and outer surfaces of thin-walled parts, and can complete the one-time processing of thin-walled parts with one clamping, thereby ensuring the coaxiality of thin-walled parts, meeting the rhythm requirements of workpiece production, and having a high product qualification rate, and is particularly suitable for the processing of slender thin-walled parts.

Claims

1. A special CNC lathe for processing thin-walled parts, characterized in that: It includes a bed, a spindle box, a Z-axis drive mechanism, an X1-axis drive mechanism, an X2-axis drive mechanism, a saddle, a tailstock, a tailstock drive mechanism, an auxiliary tool holder, a support frame and a protective structure. A cooling and chip removal system is installed on the front side of the bed. The spindle box, Z-axis drive mechanism, saddle, tailstock and tailstock drive mechanism are respectively installed on the bed. The protective structure is arranged on the outside of the bed. The Z-axis drive mechanism is used to drive the saddle to move in the Z direction. The saddle is equipped with a front tool holder, a rear tool holder and a follower tool holder. The X1-axis drive mechanism and the X2-axis drive mechanism are installed in parallel on the saddle. The X1-axis drive mechanism is used to drive the front tool holder to move in the X direction. The X2-axis drive mechanism is used to drive the rear tool holder to move in the X direction. The front tool holder is equipped with a tool holder for machining the outer circle and end of the workpiece. The outer circle cutter of the surface is installed on the rear tool holder, and the inner hole cutter for processing the inner hole of the workpiece is installed on the rear tool holder, the follower tool holder is close to the front end face of the front tool holder, and the follower tool holder is provided with a plurality of clamping units, and the plurality of clamping units are used to clamp the outer circle of the workpiece, a main shaft is arranged in the main spindle box, a sleeve is installed on the tail stock, and the sleeve is coaxially arranged with the main spindle, a chuck is installed at the rear end of the main spindle, and the chuck is used to clamp the front end of the workpiece, and the sleeve is used to tighten the rear end face of the workpiece, and the tail stock driving mechanism is used to drive the tail stock to move in the Z direction, the support frame is installed on one side of the main spindle box, and the support frame is provided with a plurality of material receiving arms, and the auxiliary tool holder is installed at the bottom of the main spindle box, and a tool for cutting the workpiece is installed on the auxiliary tool holder, and the support frame is used to support the workpiece after cutting.

2. A CNC lathe specially used for processing thin-walled parts according to claim 1, characterized in that: The guide rail surface of the bed is arranged with an inclination of 45 degrees, and a first Z axis line rail and a second Z axis line rail are installed on the guide rail surface in parallel with each other. The saddle is slidably installed on the first Z axis line rail, and the tailstock is slidably installed on the second Z axis line rail.

3. A CNC lathe specially used for processing thin-walled parts according to claim 2, characterized in that: The Z-axis driving mechanism, the X1-axis driving mechanism, and the X2-axis driving mechanism are respectively screw-driven structures.

4. A CNC lathe specially used for processing thin-walled parts according to claim 2, characterized in that: The tailstock includes a tailstock body, a first slider is installed at the bottom of the tailstock body, the first slider is slidably connected to the second Z axis rail, the tailstock drive mechanism includes a first cylinder, the first cylinder is installed on the bed, the piston rod of the first cylinder is connected to the tailstock body, a mounting tube is provided on the upper side of the tailstock body, and the sleeve is rotatably mounted on the inner side of the mounting tube through a bearing.

5. A CNC lathe specially used for processing thin-walled parts according to claim 4, characterized in that: The inner circular surface of the front end of the sleeve is provided with a circle of serrated chamfer, and the rear end of the workpiece is pre-processed with a chamfered portion. The serrated chamfer matches the chamfer size of the chamfered portion. When the sleeve is pressed against the rear end surface of the workpiece, the serrated chamfer fits with the chamfered portion.

6. A special CNC lathe for processing thin-walled parts according to claim 4, characterized in that: The sleeve is interference fit with the inner ring of the bearing, the front end and the rear end of the inner ring of the bearing are respectively pressed by the first front pressure cover and the first rear pressure cover, the first rear pressure cover is fixed to the sleeve, the front end and the rear end of the outer ring of the bearing are respectively pressed by the second front pressure cover and the second rear pressure cover, the second rear pressure cover is fixed to the mounting tube, the front side of the second front pressure cover is fixed with a third front pressure cover, sealing rings are respectively arranged between the second front pressure cover and the mounting tube, between the second rear pressure cover and the mounting tube, and between the first rear pressure cover and the sleeve, the third front pressure cover, the second front pressure cover, the sleeve and the first front pressure cover form a first labyrinth gap, the first rear pressure cover and the second rear pressure cover form a second labyrinth gap, the first labyrinth gap and the second labyrinth gap are respectively communicated with the outside atmosphere, and the first labyrinth gap and the second labyrinth gap are respectively provided with water throwing troughs.

7. A CNC lathe specially used for processing thin-walled parts according to claim 1, characterized in that: The tool rest includes a frame body, an arc-shaped hole is provided on the inner side of the frame body, a notch is provided on the bottom of the frame body, the notch is communicated with the arc-shaped hole, the upper part of the tailstock and the orthographic projection of the chuck in the Z direction fall on the inner side of the frame body respectively, the number of the clamping units is three, the three clamping units are arranged at intervals along the circumference of the arc-shaped hole, each of the clamping units includes a second cylinder, a roller made of polyurethane is connected to the piston rod of the second cylinder, each of the rollers extends into the arc-shaped hole, the three rollers are used to clamp the outer circle of the workpiece, the air pipes of the three second cylinders are respectively connected to a main air pipe and controlled by an on-off valve, and the angle between the piston rods of two adjacent second cylinders is 120°.

8. The CNC lathe specially used for processing thin-walled parts according to claim 1, characterized in that: The support frame includes a first base, a second base, a third cylinder, a fourth cylinder and a linear rail, the first base is installed on one side of the spindle box, the third cylinder and the linear rail are uprightly installed on the first base, the piston rod of the third cylinder is connected to a second slider, the second slider is slidably connected to the linear rail, the second base is fixed to the front end of the second slider, the fourth cylinder is uprightly installed on the second base, the piston rod of the fourth cylinder is connected to a cam via a crank, the cam is connected to a horizontally arranged transmission shaft via a key, the transmission shaft crosses the second slider, a guide sleeve is installed between the transmission shaft and the second slider, two material receiving arms are connected in series on the transmission shaft, the bottom end of each material receiving arm is connected to the transmission shaft through a sleeve, the sleeve is fixed to the transmission shaft through a top screw, and the top of each material receiving arm is fixed with an arc-shaped support sheet with an opening facing upward.

9. A special CNC lathe for processing thin-walled parts according to claim 1, characterized in that: The spindle is a hollow spindle, the front end of the spindle is close to the inlet of the chip conveyor of the cooling chip removal system, and when the chuck clamps the front end of the workpiece, the front end of the workpiece extends into the inner hole of the spindle.

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