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Computer gong processing mold

The height of slide guide rail shall be at least 1 / 3 of that of slide block to ensure the stability and smooth sliding of sliding block.
Attention should be paid to the opening of lubricating groove where there is sliding friction. In order to prevent the outflow of lubricating oil, the groove should not be opened into “open type”, but should be “closed type”. Generally, the annular oil storage tank can be directly milled on the milling machine with a single cutter.
For the cavity of fixed mold core, the small mold is generally cut by line cutting, which can improve the precision of the mold; while the mold cavity of the larger mold is generally processed in the form of milling, pay attention to its perpendicularity during processing, and in order to prevent the mold core from not in place during assembly, the milling depth should be 0.2mm around the mold frame, and the hole position should be pre drilled on the mold frame at the corner, which will form void avoidance after milling. Prevent the interference of the assembly die (chamfering can also be done on the die).
The angle of 1 ° should be added to the interpenetration between the insert and the mold, between the mold core and the mold core, and between the mold core and the mold frame, so as to prevent collision and injury during assembly.
The length tolerance and size tolerance of the insertion part are -0.02, -0.10 and + 0.02 respectively.
The tolerance from the bottom of the c-angle to the c-angle is + 0.01 to prevent the burring.
The main part of the body mould is made of NAK80 material, and the material of skh9 and SKH51 (material treatment: nitriding treatment is also allowed), and Viking material can be used if necessary.
After drawing the parts, the position and size of the slider should be determined first to prevent interference and insufficient strength, and then the mold kernel size method should be determined.
The tolerance of the size of the insert is – 0.01, and the tolerance of the hole in the mold is + 0. 01 (transition fit).
The sharp corner of wire cut square hole on the mold core is excessive with r0.20, and the corresponding entry part is also r0.20, so as to influence the wire diameter during wire cutting, and prevent the sharp corner part from abrasion and edge overflow.
The small pit size corresponding to the positioning ball (wave bead) is generally conical hole with bottom diameter of φ 3 and angle of 90 ° to 120 °.
The draft angle of the fixed side should be greater than that of the movable side. The high-speed computer gongs can be used to process the mold leaving on the movable side. Moreover, it can prevent the parts from deformation, especially for the parts with thin wall and easy deformation in length, and the uneven pulling force on the fixed side will easily cause the parts to warp or stay on the fixed side.
For the parts with large side core pulling force and strict part precision requirements, the secondary core pulling structure should be adopted.
The slope of inclined tip + 2 ° = the slope of hold down block (generally 18 ° or 20 ° or 22 °)
When assembling molds, the following habits should be formed:

a. Clean the surface of mold core, cavity, runner, runner plate and parting surface with air gun.

b. Before assembly, polish the surface of mold core, mold cavity, insert and parting surface with oilstone to facilitate smooth assembly.

c. Pay attention to the angle cleaning to prevent interference and bruise.

d. Before assembly, we should consider how to carry out the following work.

The side pressing block of large mold core should be designed to be locked and the bottom should be 0.5-1.0mm below the parting surface to prevent interference.
The shrinkage rate of PC + GF20 is 3 / 1000, and the shrinkage efficiency in the direction of material flow with GF is less than that in the direction of vertical material flow, which is different from other materials.
The contraction rate of POM was normal 20 / 1000, but sometimes it was 30 / 1000.
In order to prevent the parts from being scratched by the latent gate when the part is ejected, a wedge-shaped block is added 2-4mm away from the latent gate. The height of the wedge is about half of the runner, and the included angle is 10 ° on one side. The gate will be broken when ejected.
The main channel pulling well adopts an inverted cone with a depth of 8-10 mm, an included angle of 10 ° on one side, and a top diameter of a wide flow channel. The advantage of this method is that it can prevent the pulling material from one side grinding into a wedge shape from hooking the flow channel during ejection, resulting in poor parting.

There are two kinds of opening and closing devices: 1. Made of rubber, the deformation is adjusted by the central screw to adjust the tension. 2. Made of spring steel. Their functions are: delay the opening time of movable side and fixed side, apply to small nozzle mold (three plate mold) or apply to secondary ejection system.

In order to ensure whether the ejector pin and inclined pin of the mold are reset, some molds are equipped with early return mechanism (female is installed on 108 plate, male is installed on 102 plate, male is similar to thimble, the bottom is blocked with headless screw, and two are generally arranged) or microswitch (between 108 and 109 boards [power mounting element]).
Considering the screw length of the injection molding machine when clamping the mold, it is necessary to pay attention to the thickness of the upper and lower fixing plates (generally about 40mm). If necessary, the four corners should be milled lower. At the same time, in order to improve the safety, four bolt holes can be drilled on the upper and lower fixed plates according to the position of the upper holes of the injection molding machine.
The forming end of the oblique pin has a straight face, which is generally 4-6mm long. In order to slide the inclined pin between 107 and 108 plates during ejection, an R angle of 0.5mm-1mm should be poured at the bottom.
For the appearance that needs to be bitten, the degree of biting should be considered in the design of draft angle, so as to avoid the appearance strain. For some protruding parts, the cross-section will become larger after biting, so the single side should be 0.02-0.03 smaller in actual processing.
Considering that the mold closing between the fixed side and the movable side will result in break, the fixed side is 0.03-0.05 smaller than that of the movable side.
In the mould with sliding block, sometimes it is necessary to set oil groove on the inclined surface of the sliding block and the pressing block; in addition, if the forming is not affected, the processing efficiency of opening oil groove on the upper surface of the template is higher than that on the bottom of the sliding block.
The parting surface should not be selected at the required position of the surface.
The shrinkage of the fiber with fiber is 1-2% smaller than that of the flow direction, which is larger than that perpendicular to the flow direction; otherwise, it is the opposite.
The shrinkage rate of the addendum circle is 1-2 thousandth less than that of the root circle.
When the die is used for a section

The exhaust pipe of turbine whistle is refitted for automobile

This product has four models: Small Model, Medium Model , Large Model and Extra Large Model

Small Model is suitable for the displacement of 1.0-1.6, and the diameter of exhaust pipe is 32-43mm (about 67g)

Medium Model is suitable for displacement of 1.6-2.0, and the diameter of exhaust pipe is 37-48mm ( about 87g)

Large Model is suitable for the displacement of 2.0-2.4, and the diameter of exhaust pipe is 44-55mm( about 102G)

Extra Large Model is suitable for displacement above 2.4, and the diameter of exhaust pipe is 56-85 mm (about 126G)

Product Name: The exhaust pipe of turbine whistle is refitted for automobile

Easy to install, beautiful and elegant, very fashionable.Welcome to send drawings for machining

Gear processing technology

Gear processing should adopt different technology according to different structure and precision. In view of the large equipment investment, the selection of process mode (as shown in Table 1) usually takes full account of the existing resources. The control of micro deformation and process stability in the process of high-speed computer gong machining gear is relatively complex. Isothermal normalizing is usually used after blank forging in order to obtain good processing performance and uniform microstructure with trend deformation. For low-speed cylindrical gear with low accuracy requirements, gear shaving can be done before hot rolling, and no processing is required after hot rolling. There are many teeth in hot post processing of cylindrical gear according to the conditions Different from gear grinding, the cost of tooth cleaning is low, but the ability of tooth profile correction is weak, and the precision of gear grinding is high but the cost is high. The technology of edge dressing and drum tooth modification can significantly reduce the gear meshing noise and improve the transmission performance, which are widely used at present.

The straight bevel gear is mainly used in the differential. Due to the low speed and relatively low precision requirement, precision forging gear is recommended. The complicated and time-consuming manual operation of spiral bevel gear processing and machine tool adjustment has been replaced by modern special software and computer program. The introduction of finite element analysis makes the process parameter design more reliable and convenient. There are mainly two kinds of gear grinding: grinding and grinding. Due to the high cost, low efficiency and limitation of gear grinding, gear lapping is mostly used at present Recently, a large marine gear with world advanced level and equipped with adjustable propeller [gear: gear is a mechanical element with teeth on the rim that can continuously mesh and transmit motion and power. The meshing of teeth in mechanical parts has been used for a long time. Box was born in hangchi group. This product belongs to the transmission device of marine power propulsion system. It not only has the functions of deceleration, clutch and bearing propeller thrust, but also has the function of auxiliary power output and auxiliary power input, which can meet the requirements of French bv ship inspection unmanned engine room.

This product is designed and manufactured by hangchi technicians according to the order requirements of foreign customers. High speed computer gong processing synchronous belt wheel is specially equipped with adjustable paddle for transportation and ocean fishing vessels. The product is controlled by electricity and hydraulic pressure. It has clutch system and gear transmission system with clutch and deceleration functions. For the first time, the PTO / PTI function is realized on the gearbox at the same time, which can make the propeller obtain the best propulsion efficiency and realize the automatic control of ship forward and backward. The auxiliary power input can realize the function of ship emergency return when the main engine fails, and the auxiliary power output can generate power for the ship when necessary. This kind of function can be used not only as generator but also as engine, which can greatly meet the needs of users.

The product has large speed ratio and wide application range. Hangchi installed the liquid level alarm for the first time in this product. All controllers and transmitters of synchronous belt pulley are imported brands. Make its performance more safe and reliable. The gearbox adopts double pump, which simplifies the design of hydraulic system and reduces the possibility of failure.

The tightness of the sprocket should be appropriate. If it is too tight, the power consumption will be increased, and the bearing is easy to wear; if the sprocket is too loose, it is easy to jump and fall off the chain. The tightness of the chain wheel is: lift or press down from the middle of the chain wheel, which is about 2% – 3% of the center distance between the two chain wheels.
There should be no swing and skew when the sprocket is installed on the shaft. In the same transmission component, the end faces of two sprockets should be in the same plane. When the center distance of sprocket is less than 0.5 m, the deviation can be 1 mm; when the center distance of sprocket is more than 0.5 m, the deviation can be 2 mm. However, there should be no friction on the side of sprocket teeth. If the offset of two wheels is too large, it is easy to cause chain shedding and accelerated wear. Pay attention to check and adjust the offset when replacing the sprocket.
When the sprocket is seriously worn, the new sprocket and new sprocket should be replaced at the same time to ensure good meshing. Do not replace new sprocket or new sprocket separately. Otherwise, it will cause bad meshing and accelerate the wear of new sprocket or new sprocket. When the tooth surface of the sprocket is worn to a certain extent, it should be turned over in time to extend the service time.
If the new sprocket is too long or elongated after use, it is difficult to adjust. The chain link can be removed according to the situation, but it must be even. The chain link shall pass through the back of the chain wheel, the locking plate shall be inserted outside, and the opening of the locking plate shall face the opposite direction of rotation.
The sprocket should be filled with lubricating oil in time. Lubricating oil must enter the clearance between roller and inner sleeve to improve working conditions and reduce wear.
The old chain wheel can not be mixed with some new ones, otherwise it will cause impact in the transmission and break the chain wheel.
When the machine is stored for a long time, the sprocket wheel should be removed and cleaned with kerosene or diesel oil, and then coated with oil or grease and stored in a dry place.

2、 The structural design of the sprocket:

Tooth profile of sprocket

The tooth shape of the chain wheel must ensure that the chain can enter and exit the meshing smoothly and smoothly, reduce the impact and contact stress of the chain link during meshing as far as possible, and it should be easy to process.

The common tooth profile of sprocket end face is composed of three arc AA, AB, CD and a straight line BC, which is called three arc straight line profile for short. The tooth profile is processed with standard cutter. It is not necessary to draw the end face tooth profile on the sprocket working drawing. It is only necessary to mark “the tooth profile is manufactured according to the provisions of 3rgb1244-85” on the drawing. However, the axial tooth profile of the sprocket shall be drawn, as shown in Fig. 2, and the dimension shall refer to the relevant design manual. ginseng

Computer gong engraving machine

Processing center: Hong Kong, Taiwan, Guangdong area known as the computer gong, is a highly automated multi-functional CNC machine tool with tool magazine and automatic tool change device. The first machining center appeared in the United States in 1958. High speed computer gong machining can realize the centralized processing of milling, drilling, boring, reaming, tapping and other processes after the workpiece is clamped once, with special emphasis on “milling”.

Engraving machine: its spindle speed is high, suitable for small cutting tools processing, torque is relatively small, focusing on the “carving” function, such as wood (wood carving machine for special processing of wood), dual color board, acrylic plate and other plates with low hardness, which are not suitable for large workpieces with strong cutting. Most of the products on the market with the banner of engraving machine are mainly for processing handicrafts with low cost. Due to the low precision, they are not suitable for mold development. However, there are also exceptions, such as wafer engraving machine.

Carving and milling machine: as the name implies. It can be carved or milled. On the basis of the engraving machine, the power of the spindle and servo motor is increased, and the bearing force of the lathe bed is maintained. At the same time, the high speed of the spindle is maintained. More importantly, the precision is very high. Engraving and milling machine also to high-speed development, commonly known as high-speed machine, cutting ability is stronger, processing accuracy is very high, but also can directly process hardness above HRC60 materials, one-time molding.

The highest spindle speed (R / min): Machining Center 8000; engraving and milling machine is the most common 240000, high-speed machine is the lowest 30000; engraving machine is generally the same as engraving and milling machine, the engraving machine used for high gloss processing can reach 80000, but the air bearing spindle is not used.

Spindle power: the machining center is the largest, ranging from several thousand watts to tens of kilowatts; carving and milling machines are the second, generally within ten kilowatts; engraving machines are the smallest.

Cutting capacity: high speed computer gong machining center is the largest, especially suitable for heavy cutting and rough cutting; engraving and milling machine is the second, suitable for finishing; engraving machine is the smallest.

Speed: because engraving and milling machines and engraving machines are light and light, their moving speed and feed speed are faster than the machining center, especially for high-speed machines equipped with linear motor, the maximum moving speed is 120m / min

Accuracy: the accuracy of the three is similar.

From the processing size: the worktable area can better reflect this. The smallest worktable area (unit mm, the same below) of domestic machining center (computer gong) is 830 * 500 (850 machines); the largest worktable area of engraving and milling machines is 700 * 620 (750 machines), and the smallest is 450 * 450 (400 machines); engraving machines generally do not exceed 450 * 450, and the common ones are 45 * 270 (250 machines).

In terms of application objects: the machining center is used to complete the processing equipment of large milling amount of workpieces, large molds and materials with hardness comparison, which are also suitable for the opening of common molds; the engraving and milling machine is used to finish the finishing of small molds with small milling amount, which is suitable for copper and graphite processing; the low-end engraving machines are inclined to those with low hardness such as wood, double color board and acrylic plate Plate processing, high-end suitable for wafer, metal shell polishing and polishing.

Generally speaking, machining center and engraving and milling machine can do both products and molds, while engraving machine can only do products.

Tool magazine: Machining Center, where there is a tool library, is a machining center; if there is no tool library, it is called computer gong or CNC milling; generally, engraving and milling machines do not have a tool library, even if the tool magazine is selected, it is umbrella type tool library with 12 knives or in-line tool library with 6 knives; carving has no tool library.

In foreign countries, there is no term for CNC Engineering and milling machine. Strictly speaking, carving is a part of milling, so there is only the concept of machining center in foreign countries, and the concept of small machining center is derived to replace engraving and milling machine. Purchase engraving machine or CNC milling machining center is often asked their own questions, to see the actual production needs. In addition, there is a popular high-speed cutting machine (hscmachine), which is called high-speed machine in China.

2、 Analysis from the angle of numerical control

— the CNC milling center requires a general speed for the CNC system, and the spindle speed is about 0 ~ 8000 rpm
– engraving and milling machine requires high-speed CNC system, high-speed computer gong processing spindle speed of 3000 ~ 30000 rpm
High speed cutting machine requires high-speed CNC system and excellent servo motor characteristics, spindle speed of 1500 ~ 30000 rpm

The highest spindle speed (R / min): Machining Center 8000; engraving and milling machine is the most common 24000, high-speed machine is the lowest 30000; engraving machine is generally the same as engraving and milling machine, engraving machine used for high gloss processing can reach 80000, but it uses air bearing spindle instead of ordinary motorized spindle.

Cutting amount: machining center is the largest, especially suitable for heavy cutting and rough cutting; engraving and milling machine is the second, suitable for finishing; engraving machine is the smallest.

Accuracy: the accuracy of the three is similar.

From the application object: the machining center is used to complete the processing equipment of large milling amount of workpieces

Computer gong deep hole processing

Do CNC deep hole processing friends should know that CNC processing, deep hole processing is the most difficult. The so-called deep hole machining is the processing that the ratio of the length of the hole to the diameter of the hole is greater than 10 times. The deep hole processing is applied in some industrial fields of the country, such as the national military rocket body and the barrel of various guns. In these application fields, some require very high quality and precision of machining, and some require high cutting ability of processing materials The so-called CNC is the abbreviation of computer numerical control machine tool, which is the technology required for programmed control, automation and high-tech.

CNC technology is applied to deep hole processing. Because the processing technology and method of computer gong machining are very complex, few people use CNC machining center to process deep hole. If this technology is used, first of all, we should transform the CNC machining center to vibration deep hole drilling machine, and combine the advanced deep hole machining vibration cutting technology with AC frequency conversion speed regulation technology Together, it forms a kind of precise professional processing technology. This kind of precise CNC deep hole processing technology effectively applies the vibration cutting technology to the drilling process. On the basis of the traditional deep processing technology, the amplitude and frequency of the regular vibration of the tool used are given. In the process of cutting tool running, the cutting work is completed by vibration at the same time, and the cutting thickness changes periodically, so as to achieve the purpose of NC cutting according to the predetermined shape and size. Thus, the problem of chip removal interruption in CNC deep hole machining is effectively solved, and the quality and efficiency of deep hole machining are improved.

After years of efforts, the development of domestic ultra precision machining equipment has begun to take shape. The indicators of many equipment for machining mechanical parts, including aspheric surface composite machining system, have reached or approached the world advanced level In terms of reliability and operability, there is still a certain gap. How to better play the role of equipment requires further human and material investment. For example, the nano sys-300 aspheric surface compound processing equipment of our laboratory has been in the production line service since it was delivered to the user in May 2003. It has processed many batches of task parts, which can fully meet the requirements of users in terms of processing accuracy, but there is still much room for improvement in other aspects, such as operability and reliability. Therefore, it is necessary to strengthen the research on the reliability and practicability of ultra precision machining technology.

With the development of science and technology, more and more advanced new functional materials and structural materials will be applied, including new high strength, high hardness materials, intelligent materials, new semiconductor materials, and so on. For example, the processing technology of SiC reinforced composite materials used in satellite cameras, the ultra precision turning technology of infrared materials such as germanium, monocrystalline silicon and calcium fluoride glass, and the flying cutting process of KDP crystal (laser fusion), etc.

MEMS processing technology mainly includes silicon planar process and bulk silicon process developed from semiconductor processing technology. Since the mid-1980s, LIGA technology, which uses X-ray lithography, electroforming and injection molding, was born, forming another MEMS processing system. The processing technology of MEMS can include silicon micromachining for surface and bulk machining, Liga machining and quasi Liga machining using UV lithography, micro EDM, ultrasonic machining, plasma machining, laser machining, ion beam machining, electron beam machining, stereolithography, etc.

However, the components of these micromachines are various and complicated. In order to make the performance of micromachines really pass the standard and reach the practical level, it is necessary to improve the manufacturing technology and equipment level of micro mechanical parts as soon as possible. At present, lithography is the most mature technology in the manufacturing process of micro mechanical parts. Most of the classic micro mechanical parts are made by lithography or electroforming technology. However, the micromechanical parts processed by these mature technologies can only be two-dimensional (or quasi three-dimensional), and the actual three-dimensional shape parts can not be completed by lithography technology. There are many three-dimensional micro parts in CNC machining center, such as micro mold, micro thread with diameter of 70 μ m, micro rack, pin with diameter of 50 μ m, stepped shaft with diameter of 200 μ m, 100 μ m and 50 μ m, and rotary polishing with outer diameter of 300 μ M The processing of these typical three-dimensional micro parts can not be realized not only by lithography, three beam processing, but also by traditional mechanical manufacturing system. Therefore, it is necessary to develop and develop a micro manufacturing system according to the characteristics of three-dimensional micro machines. In this new concept manufacturing system, the processing, detection and assembly of micro machine parts can be realized. The manufacturing system of micro machine, which is composed of micro equipment, is called micro manufacturing system. The technical problems include the processing, detection and assembly of micro machine parts. The research work in this field is mainly concentrated in Japan and the United States. In this regard, Japan first put forward the concept of micro desktop factory.

However, it is not necessary to use micromachining machine tools to process micro mechanical parts, such as the characteristics of machine tools for processing instrument parts

WEDM fast wire and slow wire

Fast wire in the professional terminology is called: mechanical parts processing high-speed reciprocating wire EDM wire cutting machine

Slow wire is called low speed unidirectional WEDM in professional terms

The wire speed of reciprocating WEDM is 6-12 m / s. The biggest characteristic of the product is that it has 1.5 degree taper cutting function, and the processing thickness can be more than 1000 mm. It is used in all kinds of medium and low-grade mold manufacturing and special parts processing, and has become one of the most widely used machine types in China’s CNC machine tools. However, due to the fact that the reciprocating WEDM machine can not implement constant tension control on the electrode wire, and the computer gong processing, the electrode wire jitters greatly and is easy to break in the process of processing. Because the electric grade wire is used repeatedly, it will cause electrode wire loss, machining accuracy and surface quality reduction.

The electrode wire of low-speed WEDM uses copper wire as tool electrode and generally moves unidirectionally at the speed of less than 0.2m/s. A pulse voltage of 60-300v is applied between the copper wire and the processed materials such as copper, steel or superhard alloy, and a gap of 5-50um is maintained. The gap is filled with insulating medium such as deionized water (close to distilled water), which causes spark discharge between the electrode and the workpiece This is consumed and corroded, and numerous small pits are etched on the surface of the workpiece. Through the monitoring and control of NC control and the execution of servo mechanism, the discharge phenomenon is uniform and consistent during the machining of mechanical parts, so that the processed products can be processed into products with the required size and shape accuracy. At present, the accuracy is up to 0.001mm, and the surface quality is close to the grinding level. The electrode wire is no longer used after discharge, and no resistance anti electrolysis power supply is adopted. Generally, it is equipped with automatic threading and constant tension device. It has the advantages of stable, uniform, small jitter, high machining accuracy and good surface quality, but it is not suitable to process large thickness workpieces. Due to the precise structure of the machine tool, high technology content, high price of the machine tool, the use cost is also high.

It can form plastic parts with deep holes and complex shapes.

Under heat and pressure, the plastic can be heated quickly and evenly through the mold pouring system to ensure short hardening time.

The dimensional accuracy of plastic parts is easy to ensure and the flash of parting surface is thin. It is difficult to extrude plastics with fluidity less than 80mm. The forming pressure is higher than that of the glue pressing method. The consumption of plastic must be increased (pouring part).

3) Injection method: the granular or powdered plastic is heated and melted into the flowing state in the barrel of the injection machine, and then the whole cavity is filled with a narrow nozzle and the pouring system of the mold with a very high pressure and poor speed. After a certain period of setting, the mold is opened, and the plastic parts can be taken out from the mold. The characteristics of injection molding are as follows

The forming cycle is short and easy to realize. The dimensional accuracy of plastic parts is easy to guarantee.

The mold is usually designed to be fixed. When there are many metal inserts in the plastic parts, the installation of the inserts is more difficult. 4.3.2 classification of plastic mould according to forming mode

It can be divided into: thermosetting plastic pressing mold, thermosetting plastic extruding mold, thermosetting plastic injection mold and thermoplastic injection mold.

According to the form of material cavity, thermosetting plastic pressing mold can be divided into: (a) open type pressing mold, that is, the cavity is the feeding cavity; (b) the semi closed pressing mold, that is, the cross section of the feeding cavity; and (3) the shape of the cavity;

(c) The feeding cavity is the continuous part of the cavity, and the forming pressure is completely transmitted to the pressed plastic parts through the upper die.

According to the structure form, it can be divided into: (a) movable pressing die, (b) fixed pressing die. 5. Factors affecting the quality of EDM

There are many factors affecting the processing quality, which are related to the selection of electrode materials, electrode manufacturing, electrode clamping and alignment, the selection of machining standards and the appropriateness of operation process. To prevent waste products, the following points should be paid attention to. 5.1 correct selection of electrode materials

In cavity machining, graphite is a common electrode material. However, due to the variety of graphite, not all graphite materials can be used as electrode materials for EDM. Special graphite with high strength, high density and high purity should be used. Dongguan high speed computer gong processing copper electrode is often used in precision. One is: the discharge end of EDM, which is used to process cavities, lettering, etc., and is usually made into the required shape. The material is graphite, copper or aluminum (rare) CNC machining center. The other is: the discharge end of WEDM is made of molybdenum wire. Its principle is to apply high-frequency and high-voltage to the discharge end through the electric control part. When the electrode (molybdenum wire) contacts with the grounding end (workpiece), it will form high-frequency ignition and generate high temperature, which will quickly dissolve the workpiece surface (a very small gap) in contact with molybdenum wire, which is called wire cutting.

The so-called multi electrode machining refers to the parts to be processed with high precision, and the discharge parts should be discharged twice or more. In the early stage, it is rough discharge machining with larger translation, and the later is fine discharge machining with small translation

Computer gong machine failure

Fault analysis is the first step in the maintenance of computer gong processing machine tool. Through fault analysis, on the one hand, it can quickly find out the cause of the fault and eliminate the fault; at the same time, it can also play a role in preventing the occurrence and expansion of the fault. Generally speaking, the main methods for fault analysis of computer gong processing machine tools are as follows:

Conventional analysis method conventional analysis method is a method of routine inspection on mechanical, electrical, hydraulic and other parts of mechanical parts processing machine tool, so as to determine the cause of failure. On machine tools, conventional analytical methods usually include the following contents:

1) Check whether the specifications of the power supply (including voltage, frequency, phase sequence, capacity, etc.) meet the requirements; 2) check whether the connection of CNC servo drive, spindle drive, motor and input / output signal is correct and reliable; 3) check whether the printed circuit board in the CNC servo drive device is firmly installed and whether the plug-in position is loose; 4) check the CNC servo drive, spindle drive and other parts 5) check whether the oil pressure and air pressure of the hydraulic, pneumatic and lubricating parts meet the requirements of the machine tool; 6) check whether the electrical components and mechanical parts are obviously damaged

The action analysis method is a method to determine the bad action position by observing and monitoring the actual action of the machine tool and trace the root cause of the fault. Generally speaking, the hydraulic and pneumatic control parts of the computer gongs processing machine tool, such as automatic tool changing device, worktable exchange device, fixture and transmission device, can be used to determine the cause of the fault through action diagnosis.
State analysis method state analysis method is a method to determine the cause of failure by monitoring the working state of the actuator. This method is most widely used in the maintenance process of computer gongs processing machine tools. In modern CNC system, the main parameters of servo feed system, spindle drive system and power module can be tested dynamically and statically. These parameters include: input / output voltage, input / output current, given / actual speed, position, actual load condition, etc. In addition, the status of all input / output signals of CNC system, including internal relays and timers, can also be checked by the diagnostic parameters of the CNC system. Through the state analysis method, the cause of failure can be quickly found out according to the internal state of the system without instruments and equipment. It is widely used in the maintenance of computer gongs, and the maintenance personnel must be skilled Master.
Operation, programming analysis method operation, mechanical parts processing programming analysis method is a method to confirm the cause of failure through some special operations or compiling special test program segments. For example, through manual single step to execute automatic tool change, automatic table exchange action, execute single function processing instructions and other methods to detect the action and function. By this method, the cause and components of the fault can be determined and the correctness of the program can be checked.
Self diagnosis of CNC system is a self diagnosis and testing method for the key hardware and control software of the system by using the internal self diagnosis program or special diagnosis software. It mainly includes boot self diagnosis, online monitoring and offline testing.
Using precision level instrument and other detection tools, mainly by adjusting the pad iron way to fine adjust the level of the main bed of the computer gong processing machine tool, so that the geometric accuracy of the machine tool can reach the allowable tolerance range;
For the automatic tool change device, adjust the position of the tool magazine, manipulator, travel parameters, etc., and then check the action with the command, which is required to be accurate;
For the machine tool with APC automatic exchange table, after adjusting the relative position, carry out automatic load exchange;
After the adjustment of the machine tool, carefully check whether the parameter setting values in the numerical control system and the programmable controller conform to the data specified in the random index, and then test the main operation functions, safety measures, execution of common instructions, etc.

Computer gong processing – surface treatment

Computer gong processing is a kind of artificial intelligence, which is controlled by computer to complete complex processing. The most complex part of the computer gong lies in the control system. In the high-speed computer gong processing, the computer sends various instructions to control the three-axis servo motors of the machine table to cooperate with each other according to the established route, so as to process various complex processes and ensure high processing accuracy. Today, we will talk about the matters needing attention when starting the main computer gong processing:

When the computer gong machining machine tool is started or reset by pressing the emergency stop, it first returns to the reference zero position of the machine tool, so that the machine tool has a reference position for its later operation.
Clamping workpiece:
Before the workpiece is clamped, the surface should be cleaned, and there should be no oil stain, iron filings and dust during machining of mechanical parts, and the burr on the surface of the workpiece should be removed with a file (or oilstone).
The equal high-speed rail used for clamping must be grinded flat by grinding machine to make it smooth and flat. The weight iron and nut must be firm, which can reliably clamp the workpiece. For some small workpieces that are difficult to be clamped, they can be directly clamped on the vise.
The worktable of the machine tool shall be clean and free of iron filings, dust and oil stains.
Pad iron is generally placed at the four corners of the workpiece, and equal height pad iron should be added in the middle of the workpiece with too large span.
According to the size of the drawing, use a ruler to check whether the length, width and height of the workpiece are qualified.
When clamping the workpiece, according to the clamping and placing mode of the programming operation instruction, it is necessary to consider avoiding the processing position and the situation that the cutter head may encounter the fixture during the processing.
After the precision computer gong processing workpiece is placed on the pad iron, it is necessary to pull the table on the workpiece reference plane according to the drawing requirements. The workpiece length direction error is less than 0.02mm, and the top surface x, Y direction horizontal error is less than 0.05mm. The perpendicularity of the workpiece which has been ground on six sides shall be checked to see if it is qualified.
After pulling the watch, the nut must be tightened to prevent the workpiece from shifting in the process due to the loose clamping.
Pull the meter again to make sure that the error is not out of tolerance after clamping.
Workpiece collision number: for the clamped workpiece, the collision number can be used to determine the processing reference zero position. There are two kinds of collision head: photoelectric type and mechanical type. The collision selection method can be divided into middle collision number and single side collision number. The steps of dividing the collision number are as follows:
Collision method: photoelectric static, mechanical speed 450-600 rpm.
Manually move the x-axis of the worktable to make the colliding head touch one side of the workpiece. When the bumping head just touches the workpiece and the red light is on, the relative coordinate value of this point is set as zero; after high-speed computer gong processing, manually move the x-axis of the workbench to make the collision head touch the other side of the workpiece. When the collision head just touches the workpiece, record the relative coordinates at this time.
According to the relative value minus the diameter of the bumping head (i.e. the length of the workpiece), check whether the length of the workpiece meets the requirements of the drawing.
Divide the relative coordinate number by 2, and the value is the middle value of the x-axis of the workpiece. Then move the table to the middle value on the x-axis. Set the relative coordinate value of the x-axis at this point to zero, which is the zero position on the x-axis of the workpiece. With the rapid development of modern machine manufacturing industry, the requirements for machine parts are increasing. Some important parts must work under the conditions of high speed, high temperature, high pressure and heavy load. Any defect in the surface layer not only directly affects the working performance of the parts, but also causes accelerated wear, corrosion and failure of the parts. Therefore, attention must be paid to the surface quality problems.

The machining quality of machine parts, in addition to the machining accuracy, also has the machined surface quality, which is the characterization of the integrity of the surface layer after machining.

The deviation of the actual geometric parameters from the ideal geometric parameters is called machining error. The level of machining accuracy is measured by the size of machining error. If the error is large, the precision will be low, otherwise it will be high.

Machining accuracy includes three aspects: dimensional accuracy, shape accuracy and position accuracy.

① The degree to which the actual shape of the machined part surface is consistent with the ideal part surface shape. The ideal surface shape of parts refers to the absolutely accurate surface geometry.

② Dimensional accuracy the degree of correspondence between the actual size of the machined part surface itself or between the surfaces and the ideal part size. The ideal part size refers to the middle value of the dimension marked on the part.

④ The degree of correspondence between the actual position of each surface of the part and the position between the ideal parts after position precision machining. The position between the surfaces of an ideal part refers to the absolutely accurate position between the surfaces.

Computer gongs processing aluminum alloy surface treatment what

(1) Geometrical characteristics of surfaces

① Surface roughness surface roughness refers to the micro geometric error of the machined surface. The surface roughness of high-speed computer gong machining is usually formed by the moving track of cutting tool in machining, and the ratio of wavelength to wave height is generally less than 50.

② Surface waviness surface transit is a periodic geometric error between macro geometric error (△ *) and micro geometry error (i.e. roughness).

Development of gear industry

Although the gear industry is developing rapidly and there are more and more types, such as reducer spiral bevel gear, spiral bevel gear and so on, there are not many manufacturers specializing in gear mold, most of which are made by gear factory themselves, especially plastic gear in gear industry.

In terms of plastic gears, generally speaking, plastic gears and their molds are mainly distributed in two regions: Ningbo, Zhejiang Province, where there are more than 340 plastic gear factories, which is also the largest plastic gear mold production base in China; the other is Shenzhen Bao’an, which is dominated by Hong Kong funded enterprises with high product precision, which is mainly used for export. Among them, the demand for plastic gear mold is relatively large.

Throughout the current situation of gear mould in China, it can be said that there are mixed feelings. Computer gongs processing is pleased that gear mold production has a certain foundation, and the development trend of plastic gear will bring greater market space for gear mold; The worry is that there is still a gap between the level of domestic gear mould production and that of the world’s predecessors. Moreover, with the development trend of the gear industry, especially the plastic gear industry, the domestic response to market changes is not sharp enough, and the supporting research is difficult to keep up with the market demand. At present, medium and low-grade gear molds can be produced at home, and high-grade gear molds are mostly imported. The application scope of high-speed computer gongs for machining domestic gears can be roughly divided into three aspects: plastic gear mold, powder metallurgy gear mold and precision forging bevel gear mold.

It can be seen that there is still a large space for the development of China’s gear industry. Our company specializes in the production of spiral bevel gears and other products. The advanced equipment and technology ensure the quality of the products, which has been recognized by customers. Plastic gear has the advantages of low transmission noise, vibration absorption, self lubrication, high efficiency of mold processing. In recent years, the application of plastic gear in gear industry will be more and more, which will become a worldwide trend.

Domestic precision gear mould needs to keep pace with the development of world gear mould

However, at present, the middle and low-grade gear mould can be produced in China, and the high-grade gear mould mostly depends on import. There are not many factories specialized in gear mould in China, most of them are made by gear factories themselves. In the application range of gear mold, the demand of plastic gear mold is relatively large, and the market potential is huge.

Relevant experts in the industry put forward three strategies for future development

First, speed up the adjustment of industrial structure; in the future development, the gear mold industry should pay more attention to the strategic adjustment of its product structure, so as to make the high-end die with complex structure and high precision develop faster. At the same time, the mold industry should also closely follow the market demand to develop. Without product demand and product upgrading, there will be no technological progress in the mold industry, and there will be no scale and grade of mold products. The level of mold technology determines the quality, efficiency and development ability of new products to a great extent.

At present, there is neither national standard nor ready-made industrial standard for gear mold processing, especially in plastic gear mold. The technical standard is a kind of open standard, but it is very difficult to make the product standard. It is necessary to consider the test standard, precision standard and test device standard of gear mould.

Third, strengthen the density of cooperation between industries; the development of modern industry is a relationship of mutual cooperation, which is equally important for the gear mold industry. This cooperation is first of all direct cooperation in industry research. For example, several universities are engaged in the research of gear mold, concentrating the strength of gear industry and some university research institutions, and doing integrated research and cooperation in the aspects of process equipment and internal deformation law of plastics.

At the same time, from the whole industry, the voice of gear mold is very small, and it is in a spontaneous state, and the establishment of relevant professional associations is to change this situation. This is to focus on discussing and solving the problems existing in the production of small module gear, so as to promote the development of domestic precision gear mold industry.

In the trend of gear industry, especially plastic gear industry, the domestic response to market changes is not sharp enough, supporting research is difficult to keep up with the market demand, and the domestic precision gear mold still needs to keep up with the development level of the world gear mold.

Shaft gear is the most important part in the gearbox, and its machining accuracy directly affects the overall quality of the gearbox. At present, the gear tooth processing method we adopt is hobbing shaving method. In order to produce high-precision gears by hobbing and shaving, the hobbing and shaving process must be brought into full play. The shaving accuracy depends on the saddle hobbing accuracy to a large extent, so some error items in hobbing must be strictly controlled to produce high-quality gears. Gear hobbing is a common gear processing method. On the hobbing machine with high precision, gear teeth of grade 4-5 can be machined with precision hob. On the ordinary gear hobbing machine, only 8-grade precision gear teeth can be machined with ordinary precision hob. The accuracy of gear tooth of transmission shaft is required to be 8-7-7, and the positioning datum is mainly based on two center holes and end faces during gear hobbing. Therefore, it is very important to analyze the error sources of hobbing and master the methods to ensure and improve the machining accuracy.

Analysis of hobbing accuracy

The accuracy of shaft teeth is mainly related to motion accuracy, stability accuracy and contact accuracy. Common control method in Hobbing

Computer gong machining tolerance range

After refitting ordinary machine tools into economical numerical control lathes, the work efficiency can be increased by 1-4 times, the scrap rate can be reduced, the product quality can be improved, and the labor intensity of workers can be reduced. Renovation costs are usually recovered in about a year.

Generally, single board microcomputer is used as control device for high-speed Gong machining, and stepping motor is used as actuator to transform ordinary machine tool into economical numerical control lathe. The modified machine tool not only retains the versatility of the original machine tool, but also adds many features that traditional machine tools do not have, such as automatic tool setting, gap compensation, automatic feed speed adjustment, automatic return to the original point and so on. This kind of machine tool is especially suitable for the frequent and rotational processing of rod, shaft, disc parts and parts with taper and spherical surface.

Economic CNC lathes can be divided into three types according to the driving system

Open loop system driven by stepping motor. This kind of system is widely used. Economical CNC lathe can finish the machining of cylinder, plane, cone, curved surface and thread.
Point position numerical control system driven by asynchronous motor or DC motor, grating measurement feedback.
A semi closed loop system driven by DC servo motor for high speed Gong machining. This kind of system is mainly used for new machine tools because of its high price.
High speed computer gongs use precision level instrument and other detection tools, mainly by adjusting the pad iron way to fine adjust the level of the main bed of the machine tool, so that the geometric accuracy of the machine tool can reach the allowable tolerance range;
For the automatic tool change device, adjust the position of the tool magazine, manipulator, travel parameters, etc., and then check the action with the command, which is required to be accurate;
For the machine tool with APC automatic exchange table, after adjusting the relative position, carry out automatic load exchange;
After the adjustment of the machine tool, carefully check whether the parameter setting values in the numerical control system and the programmable controller conform to the data specified in the random index, and then test the main operation functions, safety measures, execution of common instructions, etc.
High speed computer gong to check the normal operation of auxiliary functions and accessories of the machine tool. It is usually composed of CNC system, main drive system, feed servo system, cooling smooth system, etc

It is used to clamp the tool and rotate the tool. The spindle speed scale and output torque have a direct impact on the machining. 2. The feed servo system is composed of feed motor and feed actuator. According to the feed rate set by the program, the relative motion between the tool and the workpiece is completed, including linear feed motion and rotary motion. 3. Control system CNC milling machine motion control in the middle of the implementation of NC machining program control machine tools for processing. Computer gong processing, Dongguan computer gong processing, high speed computer gong processing, mechanical parts processing, computer gong processing, auxiliary equipment such as hydraulic, pneumatic, smooth, cooling system, chip removal and protection equipment. 5. The base parts of high-speed computer gong machine tools usually refer to the base, column, beam, etc., which are the foundation and structure of the whole machine tool.