Fluid supply nozzle structure for minimum quantity lubrication during high-speed milling and system

Abstract

A fluid supply nozzle structure for minimum quantity lubrication in high-speed milling, comprising at least two nozzle bodies, each of which is connected at one end to a pipe housing (1-18) and provided at the other end with a spray head (I-22), wherein adjacent nozzle bodies are spaced apart from each other at a preset angle, wherein a mixing channel formed by the interior of a hollow tube is provided within the nozzle body, one end of which is connected to at least two pipes, wherein a gas is introduced into a first pipe and a lubricating oil is introduced into a second pipe, wherein a gas pipe connected to the first pipe and a lubricating oil pipe connected to the second pipe are located within the pipe housing (1-18), wherein both the gas pipe and the lubricating oil pipe are arranged around a center point of the pipe housing (1-18).

Description

Field of invention

[0001] The present invention relates to the field of milling, in particular to a fluid supply nozzle structure for minimum quantity lubrication in high-speed milling and a corresponding system. Technical background

[0002] Milling is a highly efficient machining process of workpieces using a rotating, multi-edged tool. In milling, the rotation of the cutter is defined as the main movement, and the linear or pivoting movement of the cutter or workpiece in coordinate directions is defined as the feed movement, which is suitable for machining flat or slotted workpieces.

[0003] High-speed milling is a high-performance milling process with high feed rates, low material removal rates, and higher material removal rates than deep milling. It extends the tool life and reduces downtime. Thanks to its rapid response time, it is particularly well-suited for use in modern production processes.

[0004] Current machining processes require high lubricant consumption, essentially a casting process, which poses a significant threat to the environment and human health. To meet environmental protection requirements, lubricant residues can only be removed after appropriate treatment, resulting in substantial financial costs of up to 54% of lubricant costs. This necessitates a reassessment of lubricants.

[0005] Minimum quantity lubrication (MQL) is a lubrication method for metalworking in which a pressurized gas (air, nitrogen, carbon dioxide, etc.) is mixed with a minute quantity of lubricating oil to create micrometer-sized droplets through atomization. These droplets are then sprayed onto the workpiece to achieve effective lubrication. This method uses a minimal amount of grinding fluid (approximately one-thousandth of the amount used in conventional processes) while ensuring effective lubrication and cooling, thus reducing costs and minimizing potential environmental impact and personal injury.

[0006] The MMS cutting fluid is sprayed onto the area to be machined by a high-pressure gas and can then move freely, i.e., uncontrolled, in the form of mist droplets, such as diffusing, drifting, etc. This poses a very high risk to the environment and the health of the workers. Mist droplets with a diameter of less than 4 µm can even cause various occupational diseases, such as respiratory illnesses, skin cancer, etc. It has been shown that even brief exposure to such environments can lead to impaired lung function. Therefore, the US National Institute for Occupational Safety and Health (NIOSH) proposes an exposure limit concentration of 0.5 mg / m³ for mineral oil mist droplets. 3 To ensure the health of the working personnel, it is necessary to control small to very small liquid droplets during the respective minimum quantity lubrication.

[0007] Furthermore, a high-speed milling process can generate many chips that move in all directions as the workpiece rotates and are not easy to collect, thus severely impacting the cleanliness of the environment.

[0008] Our research has shown that Jinzhao Energiespartechnik GmbH Shanghai has been heavily involved with MMS supply systems.

[0009] Our research has revealed that Li Gang invented an energy-saving minimum quantity lubrication system (patent number: CN 103 692 285 A) comprising an oil reservoir filled with lubricant, a fluid control valve arranged on one side of the oil reservoir and connected to the inlet end of the oil reservoir, a nozzle system connected to the fluid control valve, and a gas flow valve. Both the pressure regulating filter grid and the gas flow valve are connected to the nozzle system, while the gas flow valve is connected to the pressure regulating filter grid. This invention achieves precise control of the oil-gas ratio generated by the nozzle system by providing a gas flow valve and a fluid control valve on the oil reservoir, thus preventing lubricant atomization and the associated environmental pollution and waste.

[0010] Our research has revealed that Li Gang invented an oil-water-gas three-phase energy-saving minimum quantity lubrication system (patent number: CN 103 722 447 A) comprising an MQL oil injection device, a water solution injection device, and a nozzle device, wherein the minimum quantity lubrication device is filled with an aqueous solution. Compressed air can flow in the oil-water-gas three-phase energy-saving minimum quantity lubrication system, present in the form of two compressed gas streams. One compressed gas stream can reach the water solution injection device, while the other compressed gas stream is further divided into two partial streams. One partial stream flows through the oil injection device, while the other partial stream enters the nozzle device via a line. Furthermore, the MQL oil injection device and the water solution injection device are each connected to the nozzle device via a line.This invention solves existing problems in the prior art, such as uneven mixing of water and oil and unsatisfactory fluid discharge, by controlling the flow of oil, gas, or water. Furthermore, it allows for a 70%–90% reduction in the air compressor's electricity consumption. Compared to conventional lubrication methods, this invention reduces the amount of lubricant used and dispensed by more than 95%, significantly contributing to energy savings, emission reduction, and environmental protection.

[0011] Our research has revealed that Wu Qidong invented an electrolysis water-oil-gas three-phase energy-saving MMS cooling system (patent number: CN 106 064 325 A) comprising an electrolysis water generator, at least one MMS oil injection device, and at least one oil-water-gas injection device. The electrolysis water generator is connected to an external water source at its water inlet end and to the oil-water-gas injection device via a hose at its alkaline water outlet end. The compressed air splits into two air streams: one connected to the oil-water-gas injection device and the other serving as the energy source for the MMS oil injection device, whose oil outlet is connected to the oil-water-gas injection device.This advantageously eliminates problems existing in the prior art, such as large quantities of lubricant used, high environmental impacts, uneven mixing of water and oil, unsatisfactory fluid leakage effect and increased work intensity due to frequent water addition.

[0012] Our research has revealed that Zhang Naiqing invented a specific minimum quantity lubricant for an oil-water-gas three-phase minimum quantity lubrication system and its manufacturing process (patent number: CN 104 031 732 A). Such a minimum quantity lubricant comprises an oil solution A and an aqueous solution B, wherein the oil solution A consists of 40-60 wt% polyricinoleate, 30-50 wt% low viscosity synthetic ester, 2-5 wt% phosphate ester, 2-5 wt% ethanolamine borate, and the aqueous solution B consists of 95-98 wt% water, 0.5-2 wt% molybdate, 0.5-2 wt% phosphate, 0.5-1 wt% higher alcohol, 0.01-0.05 wt% benzotriazole or its derivatives. By using the specific minimum quantity lubricant produced according to the invention for an oil-water-gas three-phase minimum quantity lubrication system in combination with a minimum quantity lubrication device, the amount of cutting fluid used can be reduced by over 95%.

[0013] Our research has revealed that Zhang Naiqing invented a biodegradable minimum quantity lubrication (MQL) oil and its manufacturing process (patent number: CN 105 296 081 A), wherein the biodegradable MQL oil contains polypentaerythritol methacrylate with a concentration of 1-99% by mass. By using the MQL oil according to this invention in combination with a MQL lubrication system, the required quantity can be reduced to less than 5% of the original quantity. Furthermore, good lubrication and cooling can be achieved, which significantly contributes to energy savings, emission reduction, and environmental protection.

[0014] Our research has revealed that Zhang Naiqing invented a minimum quantity lubrication (MQL) oil made of organic molybdenum (patent number: CN 103 275 795 A), consisting of 31-100 wt% organic molybdenum, 0-69 wt% base oil for lubrication, 0-10 wt% extreme pressure wear inhibitor, and 0-10 wt% rust inhibitor. This MQL oil overcomes the problem in the prior art that difficult-to-machine metals can only be inadequately machined with a standard MQL oil.

[0015] Our research has shown that the MMS team from Qingdao University of Technology has focused extensively on nanofluid supply systems.

[0016] Our research has revealed that Li Changhe invented a lubricant supply system using nanoparticle jets for MMS grinding (patent number: CN 102 658 526A). In this system, nanoscale solid particles are added to a biodegradable grinding fluid to create a lubricant for MMS grinding. This lubricant is then converted by a minimum quantity lubrication (MQL) device into pulsed liquid droplets with a fixed pressure, variable pulse frequency, and constant droplet diameter. These droplets are injected into the grinding area in the form of jets, passing through an air separating layer created by a high-pressure gas. This system offers all the advantages of MMS technology, including improved cooling performance and excellent tribological properties.With such a system, grinding burns can be reliably avoided and the surface quality of the workpiece can be increased in order to achieve highly efficient, environmentally friendly and resource-saving production with low power consumption.

[0017] Our research has revealed that Li Changhe invented a grinding fluid supply system for low-temperature cooling and minimum quantity lubrication using nanoparticle beams (patent number: CN 103 231 310 A), which comprises at least one minimum quantity lubrication and low-temperature cooling nozzle unit. This unit is mounted laterally on the grinding wheel housing of a grinding wheel and is aligned with the workpiece on the worktable. It includes an MQL atomizing nozzle and a low-temperature cooling nozzle. The MQL atomizing nozzle is connected to a nanofluid line and a compressed air line, while the low-temperature cooling nozzle is connected to a low-temperature coolant line. Furthermore, the nanofluid line, the compressed air line, and the low-temperature coolant line of each unit are each connected via a control valve to a nanofluid supply system, a cryogenic medium supply system, and a cryogenic medium supply system, respectively.The system is connected to a compressed air supply system, with the nanofluid supply system, the cryogenic medium supply system, and the compressed air supply system in turn being connected to a control unit. This system reliably prevents grinding burns and improves the surface quality of the workpiece, enabling highly efficient, environmentally friendly, and resource-saving production with low power consumption.

[0018] Our research has revealed that Zhang Yanbin invented an internal cooling system for minimum quantity lubrication (MQL) using a nanofluid in the form of electrostatically atomized, controllable beams (patent number: CN 104 191 376 A). This system comprises an adjustable high-voltage DC power supply, an internally cooled tool changer, a high-voltage conversion device, and an integrated nozzle. The MQL system supplies an internally cooled drill bit with MQL cutting fluid via the internally cooled tool changer. The positive current from the adjustable high-voltage DC power supply is transferred via the high-voltage conversion device to the needle electrode of the integrated nozzle, while the negative current is grounded and transferred to the workpiece via an electromagnetic connection to generate a corona-charged field in the needle electrode-workpiece area.Electrostatic atomization is achieved through corona charging of the MMS cutting fluid. This electrostatic atomization allows for controllable distribution of the MMS cutting fluid mist droplets during injection, increases the uniformity of the droplet spectrum, improves deposition efficiency and fluid utilization, and effectively controls the movement of the mist droplets, thereby reducing potential environmental impacts and providing better health protection for personnel.

[0019] Our research revealed that Li Changhe invented a three-phase flow supply system using nanoparticle beams for MMS loops (patent number: CN 102 287 606 A). In this system, a nanofluid is conveyed through a liquid line to a nozzle, while simultaneously a high-pressure gas flows into the nozzle via a gas line to mix and atomize the high-pressure gas and nanofluid in the nozzle's mixing chamber. After acceleration in an acceleration chamber, the mixture enters a swirl chamber. At the same time, a pressurized gas flows into the swirl chamber through a gas passage opening. This further mixes and accelerates the three-phase flow through a rotation, and the resulting liquid droplets are then sprayed through the nozzle outlet onto the area to be ground.This invention offers the following advantages: The gas passage opening of the nozzle's mixing chamber, extending in the direction of rotation, is tangent to the wall surface of the mixing chamber, allowing for uniform mixing of the nanofluid and gas. Pressure regulating valves, throttle valves, and flow meters are arranged in the liquid and gas lines, enabling the pressure and flow of the nanofluid and high-pressure gas to be regulated as needed to achieve optimal minimum quantity lubrication. This increases the cooling capacity of the minimum quantity lubrication system, reduces lubricant consumption for grinding, lowers disposal costs, and protects the environment.

[0020] Our research has revealed that Wang Sheng designed a gas-cap-type MMS supply device (utility model number: CN202572162U) in which nanoscale solid particles are added to a biodegradable grinding fluid to produce a lubricant for MMS grinding. This lubricant is then converted by a minimum quantity supply unit into pulsed liquid droplets with a fixed pressure, variable pulse frequency, and constant droplet diameter. These droplets are injected in jets into the area to be ground under the influence of an air separating layer created by a high-pressure gas. It possesses all the advantages of MMS technology and offers improved cooling performance and excellent tribological properties.This allows grinding burns to be reliably avoided and the surface quality of the workpiece to be increased, in order to achieve highly efficient, environmentally friendly and resource-saving production with low power consumption.

[0021] Our research has revealed that Li Changhe invented an MMS grinding device with controllable transport of nanoparticle beams under a magnetically enhanced electric field (patent number: CN 103 612 207 A), in which the electrical charge of the liquid droplets is increased by providing an additional magnetic field in the vicinity of a corona zone. It comprises a nozzle outside of which a high-voltage direct current electrostatic generator and a magnetic field generation device are located. The nozzle is connected to a nanoparticle liquid supply system and a gas supply system, while the high-voltage direct current electrostatic generator is connected to the negative terminal of a controllable high-voltage direct current source. The positive terminal of this source is connected to a workpiece current-energizing device placed on the non-machined surface of the workpiece to enable a negative corona discharge.The magnetic field generation device is located in the vicinity of a corona zone where an electrostatic discharge occurs. The nanofluid grinding fluid emerges from the nozzle's spray head and, through atomization, forms liquid droplets. These droplets are charged by the high-voltage direct current electrostatic generator and the magnetic field generation device and then introduced into the area to be ground.

[0022] Our research revealed that Li Changhe designed a grinding device with minimum quantity lubrication and cooling using nanopowder (utility model number: CN201632932U). This device features a lubricating oil reservoir, a water reservoir, and a nanopowder reservoir, with a flow control valve and a power supply unit located below each reservoir. During operation, high-pressure air, lubricating oil, water, and nanopowder are pumped into a mixing zone for atomization. This mixture produces nanoparticles and a water-in-oil grinding fluid, which is then delivered to the grinding area via a hose or nozzle. Only a very small amount of grinding fluid is required, and the lubricating oil consumption is typically no more than 50 ml / h, which is only 1 / 20 to 1 / 50th of the amount used in conventional machining processes.The amount of nanopowder used does not exceed 100 g / h. Furthermore, the compressed air can also be used for chip removal and cooling, thus simplifying the cleaning process for workpieces, extending the service life of the cleaning agent, and eliminating the need for a separate cooling circuit, resulting in a significant reduction in energy consumption. Additionally, friction between the tool and workpiece, as well as between the tool and chips, can be effectively reduced to extend tool life and improve machining quality. This avoids the disadvantages of the current state of the art, contributing to both increased productivity and environmental protection.

[0023] Our research has revealed that Li Benkai invented a nanofluid MMS grinding device with an electrostatically coupled, internally cooled thermoelectric grinding wheel and a method for its operation (patent number: CN 105 522 487 A). This involves producing a nanometer- or micrometer-sized powder from a material capable of generating the so-called thermoelectric effect. This powder is then added to a grinding wheel binder to create a thermoelectric grinding wheel. Simultaneously, electrostatic atomization, magnetically amplified electrostatic neutralization cleaning, and electrostatic deposition are used to create a grinding device with electrostatically coupled internal cooling of the grinding wheel.This method not only lowers the temperature in the grinding area but also cleans the grinding surface of the grinding wheel to prevent clogging and significantly reduces the amount of oil mist in the surrounding area during the grinding process. This device allows for a sufficient reduction in the grinding temperature, thereby increasing machining performance and quality. Furthermore, it reduces the environmental and health hazards associated with oil mist, thus meeting the requirements for mechanical machining as well as those related to energy conservation and environmental protection.

[0024] Our research has revealed that Li Changhe invented a minimum quantity lubrication (MQL) rotary system using a nanofluid in the form of electrostatically atomized, controllable beams (patent number: CN 104 209 806 A), which includes a controllable power source with multiple negative terminals. The controllable power source with multiple negative terminals has several negative terminal interfaces operating at different voltages and at least one positive terminal interface, with the negative terminal interfaces operating independently. An internal integrated nozzle and an external integrated nozzle are arranged on the internally cooled rotary tool, with both nozzles located near the tool to supply a lubricant to the turning process. For this purpose, each nozzle is connected via an internal cooling hole within the internally cooled rotary tool to a MQL system to provide a lubricating cutting fluid.Simultaneously, each is connected via a conductor to various negative terminal interfaces of the adjustable power source with multiple negative terminals. Furthermore, an electromagnetic connection is connected via a conductor, which is simultaneously grounded, to the positive terminal interface of the adjustable power source with multiple negative terminals and is attached to the internally cooled rotary tool. This invention enables controllable distribution during the injection process, an increase in the uniformity of the mist droplet spectrum, the deposition efficiency, and the effective utilization of the liquid, as well as control of the mist droplet movement in order to reduce potential environmental impacts.

[0025] In summary, the state of the art has dealt with the application of a minimum quantity lubrication system in mechanical machining and has proposed corresponding concepts and designs, which, however, are neither suitable for lubrication and cooling during high-speed milling of disc-like parts, nor can they contribute to the realization of an oil-water-gas chip separation and collection device.

[0026] CN 2 01 913 503 U relates to a self-priming circulating cooling system for machine tools, based on the principle of a vacuum generator and creating a vacuum self-priming effect using compressed air. CN 1 04 985 477 A relates to an oil-water-gas three-phase mixing nozzle consisting of a nozzle body and a fitting ring, the nozzle body having a head, a middle, and a bottom section. DE 37 43 968 C1 relates to a cooling and lubrication device in which liquid and pressurized gas are fed into an upstream mixing chamber via separate lines and then sprayed together onto the cooling point through an outlet opening. US 7 931 427 B1 relates to a programmable cooling device for cutting tools with two channels formed from annular channel elements, each with a nozzle for targeted fluid supply to the cutting tool and a control unit for selectively controlling the fluid supply to the individual channels. Disclosure of the invention

[0027] The present invention is based on the objective of offering a nozzle structure for minimum quantity lubrication during high-speed milling of disc-like parts, in which the diameter of the nozzle can be adapted to the dimensions or size of a workpiece and in which several spray heads are arranged, wherein the number of spray heads involved in the respective lubrication and cooling is controlled depending on the dimensions of the workpiece to be machined.

[0028] A further object of the present invention is to provide a gas-liquid chip separation and recovery device for high-speed milling machines with minimum quantity lubrication, with which oil-gas chip separation and collection can be achieved and the release of lubricant into the air can be avoided in order to prevent associated air pollution and to ensure the safety of the working personnel.

[0029] To solve these problems, the invention proposes the following as a first embodiment: A fluid supply nozzle structure for minimum quantity lubrication in high-speed milling comprises at least two nozzle bodies, each connected at one end to a pipe housing and provided with a spray head at the other end, wherein adjacent nozzle bodies are spaced apart from each other at a preset angle, wherein a mixing channel formed by the interior of a hollow tube is provided within the nozzle body, one end of which is connected to at least two pipes, wherein a gas is introduced into a first pipe and a lubricating oil into a second pipe, wherein a gas pipe connected to the first pipe and a lubricating oil pipe connected to the second pipe are located within the pipe housing, wherein both the gas pipe and the lubricating oil pipe are arranged around a center point of the pipe housing.The nozzle body is connected to the pipe housing via a thread at its end.

[0030] The fluid supply nozzle described above can be arranged in a ring shape to lubricate and cool the milling section. Since the ring shape matches or resembles the shape of the milling section, a large contact area with the machining section and thus good lubrication can be expected.

[0031] The pipe housing comprises at least two pipe housing sections, wherein an articulated connecting element is arranged between adjacent pipe housing sections, which may be designed as a hinge to facilitate opening the pipe housing and thereby simplify assembly or to allow adaptation to differently dimensioned milling tools or workpieces.

[0032] In appearance, the nozzle body has the shape of a serpentine cardan joint, which allows the direction of the associated spray head to be adjusted in order to control the flow direction of the sprayed fluid.

[0033] An adjusting rod is arranged between each pair of adjacent pipe housing sections, allowing the opening angle of the two pipe housing sections to be set. This adjusting rod serves two purposes: firstly, to determine the distance between the two pipe housing sections, and secondly, to adjust the opening angle of the two pipe housing sections.

[0034] The adjusting rod comprises two threaded rods, which are connected at one end to a common mounting adjusting tube and at the other end each to the pipe housing via a mounting adjusting rod screw, the pipe housing being further provided to be an arc-shaped housing.

[0035] In addition, the hollow tube has a larger inner diameter than the first pipe and the end of the first pipe, where it is connected to the hollow tube, is bent, with the first pipe having an opening with a projection into which the second pipe is inserted with a bent end.

[0036] Alternatively, it is provided that the end of the second pipe, where it is connected to the hollow pipe, is bent, the second pipe having an opening with a projection on its circumference and into which the first pipe is inserted with a bent end.

[0037] It is further stipulated that the curved end of the first pipe forms an angle ε of 18°≤ε≤22° with the curved end of the second pipe.

[0038] In a further embodiment of the invention, when several nozzle bodies are present on one side of the pipe housing, a rotatable hose clamp is arranged for adjusting the gas flow rate in the first pipe and the lubricating oil flow rate in the second pipe. This clamp projects from the pipe housing at one end. The rotatable hose clamp is cylindrical in shape and can be screwed into the pipe housing. Inside the pipe housing, on the opposite side, a projection is arranged that, together with the screwed-in rotatable hose clamp, serves to compress the first and second pipes to control the gas flow rate and oil quantity of the nozzle bodies on both sides of the nozzle assembly. The first, second, and third pipes are all hoses.

[0039] It is further provided that the pipe casing comprises two pipe casing sections, each of which is provided on one side with three nozzle bodies, wherein there is an angle γ of 35°≤γ≤40° between adjacent nozzle bodies on a pipe casing section, an angle β of 2°≤β≤5° between the two pipe casing sections, and an angle δ of 10°≤δ≤15° between a nozzle body and the edge of the pipe casing section on which this nozzle body is located.

[0040] To reduce potential environmental pollution, the nozzle also includes a third pipe connected to the hollow tube, into which water is introduced.

[0041] It is further planned that - the end of the first pipe, where it is connected to the hollow pipe, is bent, the first pipe having an opening with a projection on its circumference, into which both the second pipe and the third pipe are inserted with a bent end, - the first pipe has an inner diameter that is larger than the inner diameter of the second and third pipes, but smaller than the inner diameter of the hollow pipe, - the first pipeline forms an angle η of 10°<η<14° with both the second pipeline and the third pipeline.

[0042] As a second embodiment, the invention proposes the following: A fluid supply system for minimum quantity lubrication in high-speed milling comprises a fluid supply nozzle structure arranged within a box body. On one side of the nozzle structure is an oil-water-gas-chip collection hood, which is connected to an oil-water-gas-chip separation device located outside the box body. The pipe housing is arranged circumferentially around the milling cutter. If the cutter axis is horizontally oriented, the pipe housing extends vertically and is arranged in a semicircle around the cutter. A viewing window is provided on one side of the box body to allow observation of the milling process.

[0043] An opening is formed on one side of the housing, facing the respective machine tool, to allow the collection of the lubricating oil used during the milling process and the chips produced during that process. The inlet pipe of the oil-water-gas-chip collection hood is oriented perpendicular to the position of the milling cutter.

[0044] The oil-water-gas-chip separation device described above is designed to remove chips from a chip-carrying gas in order to minimize air pollution. For this purpose, the opening of the oil-water-gas-chip collection hood is located near the cutting point of the cutting section.

[0045] Furthermore, the first and second pipelines are provided for by passing through the box body and being clamped in place by means of a common conveying pipe clamp, the conveying pipe clamp being located inside the box body and featuring a conveying track on the surface of the box body. If a third pipeline is present, the three pipelines are secured by means of a second conveying pipe clamp so that water collection by gravity can also be carried out by the oil-water-gas-chip separator.

[0046] The conveying pipe mounting clamp comprises two opposing clamp halves, each of which is curved at both ends and is fixed together by means of a screw in order to clamp the pipes located between them.

[0047] The oil-water-gas-chip separator is a semicircular vortex cyclone dust separator with an inlet cone angle α of 5° ≤ α ≤ 10° to increase the flow velocity into the dust separator and prevent obstruction of the gas mixture at the inlet, thus avoiding a reduction in flow rate. To ensure tangential gas entry with respect to the wall surface, a θ° arc disk with a radius of D0 / 2 and a height h1 is provided inside the cyclone dust separator, where D0 represents the cylinder diameter and h1 the inlet height. The arc disk increases the tangential velocity v of the gas flow entering the separator, thereby facilitating oil-water-gas-chip separation. A collection funnel is located at the lower end of the cyclone dust separator.The cyclone dust separator is mounted on a support. A cyclone dust separator is a device used to separate gas-solid or liquid-solid systems. During operation, a gas stream is introduced tangentially and set into rotation so that solid particles or liquid droplets, which are subject to a higher inertial centrifugal force, are flung towards the outer surface and thus separated.

[0048] The present invention offers the following advantages: 1) In the fluid supply nozzle structure according to the invention for minimum quantity lubrication in high-speed milling, the diameter of the nozzle can be adapted to the dimensions or size of a workpiece. Several spray heads are arranged on the nozzle structure, the number of spray heads involved in the respective lubrication and cooling being controlled depending on the dimensions of the workpiece to be machined, in order to lubricate and cool the milling section effectively. 2) By providing a box body according to the invention, flying chips and splashing mist droplets can be reliably prevented, thereby reducing environmental pollution and personal injury caused by machining processes. At the same time, the oil-water-gas chip separation and recovery device enables effective separation of lubricant, chips, and gas, thus protecting the environment from contamination. 3) With the aid of the nozzle according to the invention, both two-phase lubrication and cooling with oil and gas as well as three-phase lubrication and cooling with water, gas and oil can be achieved. Presentation of the illustrations

[0049] They show Fig. 1 an axonometric view of a high-speed milling and oil-water-gas chip collection device; Fig. 2 an axonometric view of a high-speed milling machining section; Fig. 3-5 each a right side view, a front view or a top view of a high-speed milling and oil-water-gas chip collection device; Fig. 6 an axonometric view of an MMS nozzle assembly; Fig. 7 an axonometric view of an oil-water-gas-chip separator; Fig. 8 an axonometric view of an oil-water-gas chip separation support device; Fig. 9 a partial section of Fig. 8; Fig. 10 a complete sectional view of a spray head of an MMS nozzle; Fig. 11(a) and Fig. 11(b) each in axonometric or sectional view a first embodiment of a mixing element of a spray head of an MMS nozzle; Fig. 12(a) and Fig. 12(b) a second embodiment of a mixing element of a spray head of an MMS nozzle, in each case in axonometric or sectional view; Fig. 13 a cardan joint for an MMS nozzle and a delivery pipe; Fig. 14 an axonometric view of an oil-water-gas delivery pipe mounting clamp; Fig. 15(a), Fig. 15(b), Fig. 16(a) and Fig. 16(b) each a sectional view of an oil-water-gas-chip separator; Fig. 17(a) and Fig. 17(b) each an axonometric assembly drawing or a top view of a filter grid ring, a filter grid and a collecting mouthpiece; Fig. 18(a), Fig. 18(b) and Fig. 18(c) each in axonometric view a collecting mouthpiece, a filter grid or a filter grid ring; Fig. 19(a), Fig. 19(b) and Fig. 19(c) each in a cutaway partial view a first embodiment of an MMS nozzle; Fig. 20(a), Fig. 20(b) and Fig. 20(c) each in a cutaway partial view a second embodiment of an MMS nozzle. Reference symbol list I-01 Conveyor pipe I-02 Conveyor pipe mounting piece I-03 Box body I-04 Viewing window I-05 milling cutter I-06 Mounting screw I-07 Workpiece I-08 Cardan joint I-09 Conveyor pipe mounting clamp I-10 Mounting clamp screw I-11 Mounting clamp nut I-12 Oil-Water-Gas Pipeline I-13 Mounting Adjustment Rod Screw I-14 Mounting Adjustment Rod I-15 Mounting Adjustment Tube I-16 Gas Pipe I-17 oil pipe I-18 Pipe Housing I-19 hinge I-20 hinge screw I-21 hose clamp I-22 spray head I-23 Mixing Element I-24 water pipe II-01 Collector hood II-02 Bbere Cover of the separator device II-03 Oil-Water-Gas-Chip Separator II-04 Collection funnel II-05 Separator bolt II-06 Sealing ring II-07 Separator nut II-08 Filter grid ring II-09 Filter grid II-10 collecting mouthpiece III-01 Separator carrier III-02 Separator support ring III-03 Separator screw III-04 Separator Mother Specific embodiments

[0050] The embodiments contained in the exemplary embodiments of the invention are described clearly and completely below with reference to the drawings accompanying the exemplary embodiments.

[0051] Fig. Figures 1 to 5 show the structure of a fluid supply system for minimum quantity lubrication in high-speed milling.

[0052] As in Fig. As shown in Figure 1, the fluid supply system for minimum quantity lubrication in high-speed milling consists of a high-speed milling section I, an oil-water-gas chip collection section II and an oil-water-gas chip separation support section III.

[0053] Out of Fig. Figures 2-5, 13, and 14 show that a conveying tube I-01 is connected to a pipe housing via a serpentine universal joint I-08, with two pipe housing sections forming a semicircle that encloses a milling cutter from above and below. The nozzle is located in an area where a workpiece comes into contact with the high-speed milling cutter during machining and is aligned with the arc line. The oil-water-gas conveying tube I-01 is attached to the top of the box body by means of a conveying tube mounting piece I-02, which rests against the box body I-03. The device contains two conveying tubes, each held and secured by a conveying tube mounting clamp I-09.The gas conveying pipe I-01, connected to the semicircular nozzle, is attached to the box body I-03 by means of the conveying pipe mounting piece I-02. The conveying pipe mounting piece consists of two joined blocks of magnetic material, and the box body I-03 is made of iron, so that the conveying pipe mounting piece adheres to the top of the box body I-03 under the influence of magnetic attraction. A horizontally extending oil-water-gas conveying pipe track I-12 is formed in the box body I-03. The conveying pipe can be moved along this track by the conveying pipe mounting piece to adjust the position of the conveying pipe and the nozzle relative to the milling cutter. A mounting screw I-06 is provided on the mounting piece, which serves to fix the position of the conveying pipe relative to the box body and the nozzle. The machining of the workpiece can be observed through a viewing window I-04.

[0054] In the representations according to Fig. 6, Fig. 10, Fig. 11(a) and Fig. Figure 11(b) shows a semicircular MMS nozzle, wherein oil is supplied by an oil delivery tube connected to the upper structure of the nozzle and gas is supplied by a gas delivery tube connected to the lower structure of the nozzle. This structure has six spray heads distributed on two interconnected pipe housing sections I-18, the nozzle body being externally connected to the pipe housing via a thread. To avoid overlap of the spray head angles and the associated waste, an angle γ of 35° ≤ γ ≤ 40° is provided between adjacent nozzle bodies on a pipe housing section, an angle β of 2° ≤ β ≤ 5° is provided between the two pipe housing sections, and an angle δ of 10° ≤ δ ≤ 15° is provided between a nozzle body and the edge of the pipe housing section on which that nozzle body is located.The pipe housing sections I-18 are connected to each other via a hinge I-19 and are each connected on one side to a fixing adjustment rod I-14 via a fixing adjustment rod screw I-13, the two fixing adjustment rods I-14 being threaded together via a fixing adjustment tube I-15. The two fixing adjustment rods I-14 are oriented in opposite directions with respect to their thread rotation, while the fixing adjustment tube I-15 is threaded at both ends, the direction of rotation of which corresponds to the thread rotation of the respective fixing adjustment rod I-14. A hose clamp I-21 is arranged on the other side of the pipe housing sections.The six spray heads effectively lubricate and cool the workpiece and tool by mixing the gas, oil, and water conveyed through delivery tubes in a mixing element I-23 before exiting the six spray heads. Furthermore, the pipe housing of the nozzle structure can be adjusted to the dimensions of the workpiece using the hinge I-19 and then secured with the fastening rod screw I-13, the fastening rod I-14, and the fastening tube I-15.Since the water, gas and lubricating oil pipes inside the nozzle are each formed by a hose, the water, gas and oil pipes inside the nozzle can be adjusted for small workpieces by turning the hose clamp I-21 so that the hoses inside the nozzle are compressed to reduce the amount of gas and oil entering the spray heads located at both ends of the pipe housing to zero.

[0055] As can be seen from Fig. 7, Fig. 15(a), Fig. 15(b) and Fig. 16(a), Fig. 16(b), Fig. 17(a), Fig. As shown in Figure 17(b), the oil-water-gas-chip separator II-03 is inserted at its front end into a collecting hood II-01 and is connected at its lower end to a collecting funnel II-04 via a flange and bolted connection, with a sealing ring II-06 arranged between the separator II-03 and the collecting funnel II-04 to prevent a drop in gas pressure. Furthermore, a collecting nozzle II-10 is connected to the collecting funnel II-04 via a threaded connection, while a filter grid II-09 is attached to the upper end of the collecting nozzle II-10 by means of a filter grid ring II-08.The high-pressure, high-velocity liquid mixture exiting the high-speed milling section via the nozzle enters the oil-water-gas-chip collection hood II-01 together with chips. A cone angle α of 5°≤α≤10° is provided at the inlet of the separator, so that the mixture of oil, water, gas, and chips enters the separator, a semicircular vortex cyclone dust separator (whose dimensions and parameters are designed according to the "Selection Manual for System and Equipment Design for Dust Separation Devices"), along the wall surface.

[0056] The centrifugal force acting on the dust particles inside the cyclone dust separator can be determined using the following physical equation (1): F=mω2R=mv2R=πρd3v26R

[0057] This formula contains F represents the centrifugal force acting on a dust particle in N, ω represents the angular velocity in rad / s at which a dust particle rotates around the axis of the cyclone dust separator (i.e., rotational angular velocity). R represents the distance between a dust particle and the axis of the cyclone dust separator (radius of rotation) in m, m represents the mass of a dust particle in kg, d represents the diameter of a dust particle in m, ρ represents the pure density of the dust particles in kg / m³ 3 , v represents the tangential velocity of a dust particle in m / s.

[0058] Upon entering the cyclone dust separator, the gas stream undergoes a rotational movement, moves towards the outer wall under the influence of an inert centrifugal force, and descends along the wall surface under the influence of gravity, with the separated chips falling into the collection hopper II-04. An upper cover for the separator unit II-02 prevents the chips from escaping upwards along with the rotating gas stream.

[0059] The dust separation efficiency of the dust separator is reflected in the minimum dust particle diameter that can be captured by the dust separator, i.e., the critical particle diameter d. c , which is calculated according to the following formula (2): dc=K18μρπv×bh1h

[0060] This formula contains d c for the critical particle diameter of the captured dust particles in m, K for the correction factor for the properties of the dust particles, µ for the dynamic viscosity of the gas in P (1Pa·s=10P), ρ represents the density of dust particles in kg / m³ 3 , v represents the tangential velocity of the gas flow in m / s, b, h1, h represent the dimensions of the cyclone dust separator in m, where h represents the height of the inner cylinder, b represents the inlet width and h1 represents the inlet height.

[0061] The smaller the critical particle diameter, the better the dust collection efficiency of the dust collector. To increase the dust collection efficiency, h and the tangential velocity of the incoming gas flow v should be increased as much as possible.

[0062] From the following continuity equation (3): Av=C

[0063] This formula contains A for the cross-sectional area in m² 2 , v represents the flow velocity of a fluid in m / s, C for constant in m 3 / s.

[0064] By providing a θ° circular arc disk (50°≤θ≤70°) with a radius of D0 / 2 and a height h1 inside the dust separator, where D0 represents the cylinder diameter and h1 represents the inlet height of the dust separator, the tangential velocity is increased relative to the inlet velocity, which can lead to better oil-water-gas-chip separation and collection.

[0065] Based on the determined minimum chip length dimension d that can be separated by the cyclone dust separator c The mesh diameter d should meet the condition 2d≤dc The design of the filter screen II-09 prevents the chips falling into the collection hopper II-04 from passing through it, thus allowing the chips to be separated from the oil and water. Once the chips, oil, and water have fallen into the collection hopper, the oil and water pass through the filter screen and continue to fall, while chips larger than the mesh diameter remain on the screen. When a certain quantity of chips has been collected, the filter screen is unscrewed to allow the collected chips to be reused.

[0066] In Fig. 8 and Fig. Figure 9 shows that a separator device carrier ring III-02 is attached to a separator device carrier III-01 by means of a separator carrier screw III-03 and a separator carrier nut III-04.

[0067] Out of Fig. 10 an MMS nozzle body emerges which has an external serpentine cardan joint with which the spray direction can be adjusted.

[0068] In the representations according to Fig. 11(a) and Fig. In Figure 11(b), an angle ε of 18° ≤ ε ≤ 22° is discernible, which is intended to prevent a significant change in the direction of the gas that would otherwise lead to energy loss. The oil pipe is inserted into the gas pipe, with gas and oil mixing occurring at the connection point. The gas pipe has a larger inner diameter than the oil pipe and serves as the main component, such that thorough mixing of gas and oil can occur when the oil pipe is inserted into the gas pipe.

[0069] In the representations according to Fig. 12(a) and Fig. In Figure 12(b), an angle η of 10° ≤ η ≤ 14° is discernible. The water pipe and the oil pipe are inserted into the gas pipe, with gas, oil, and water mixing at the connection point. The gas pipe has a larger inner diameter than the oil pipe and the water pipe and serves as the main component, such that when the water pipe and the oil pipe are inserted into the gas pipe, intensive mixing of gas, oil, and water can occur.

[0070] Fig. Figure 13 shows a cardan joint for an MMS nozzle and a conveying tube, which can be used both for angle adjustment and for carrying a not very heavy nozzle.

[0071] In Fig. 17(a), Fig. 17(b), Fig. 18(a), Fig. 18(b) and Fig. Figure 18(c) shows an oil-water-gas filter device with square d×d filter meshes. The filter grid II-09 is arranged at the upper end of the collection nozzle II-10 and has a diameter that is smaller than the outer diameter of the collection nozzle II-10, but larger than the inner diameter of the collection nozzle II-10. The filter grid II-09 is attached to the collection nozzle II-10 by means of a filter grid ring II-08, the ring diameter of which is slightly smaller than the outer diameter of the collection nozzle II-10.

[0072] Fig. 19(a), Fig. 19(b) and Fig. Figure 19(c) shows a first embodiment of an MMS nozzle providing for the mixing of oil and gas, wherein a biodegradable vegetable oil, a lubricating grease, or a non-biodegradable mineral oil can be used as the lubricating oil. The branch pipe of the oil pipe and the gas pipe is connected to the mixing element I-23, wherein the gas pipe I-16 and the oil pipe I-17 are each positioned via a projection formed on the mixing element I-23.

[0073] Fig. 20(a), Fig. 20(b) and Fig. Figure 20(c) shows a second embodiment of an MMS nozzle which provides for three-phase mixing of oil, gas and water and is operated in the manner described above.

[0074] In the lubrication system described above, a semicircular MMS nozzle is arranged in the housing on the side where the milling cutter contacts the workpiece, and a chip separation device is located on the other side. The high-pressure gas, carrying a cutting fluid, exiting the nozzle lubricates and cools the milling section. Subsequently, chips are carried by the high-pressure gas into the oil-water-gas chip separation device, where the mixture of gas, liquid, and solid particles circulates along the wall surface of the separator. Under the influence of an inert centrifugal force, chips and liquid droplets are flung toward the outer wall surface and thus separated from the gas.The chips thus separated enter the collection hopper, with relatively large chips being retained by the filter grid, while oil and water fall through the filter grid to complete oil-gas chip separation and collection.

[0075] The above descriptions represent only preferred embodiments of the invention. It will be clear to the average person skilled in the art that a number of improvements and modifications are possible within the scope of the invention, which also fall within the scope of protection of the invention.

Claims

[1] Liquid supply nozzle structure for minimum quantity lubrication in high-speed milling, comprising at least two nozzle bodies, each of which is connected at one end to a pipe housing (1-18) and provided at the other end with a spray head (I-22), wherein adjacent nozzle bodies are spaced apart from each other at a preset angle, wherein a mixing channel formed by the interior of a hollow tube is provided within the nozzle body, the end of which is connected to at least two pipes, wherein a gas is introduced into a first pipe and a lubricating oil is introduced into a second pipe, wherein a gas pipe connected to the first pipe and a lubricating oil pipe connected to the second pipe are located within the pipe housing (1-18), wherein both the gas pipe and the lubricating oil pipe are arranged around a center point of the pipe housing (1-18). [2] Fluid supply nozzle structure for minimum quantity lubrication during high-speed milling according to claim 1, characterized by , that the pipe housing (1-18) comprises at least two pipe housing sections, wherein an articulated connecting element is located between adjacent pipe housing sections and at least one nozzle body is arranged on each of the pipe housing sections, wherein it is further provided that an adjusting rod is arranged between each pair of adjacent pipe housing sections, with which an opening angle of the two pipe housing sections can be adjusted, and that the nozzle body has the appearance of a serpentine cardan joint (1-08). [3] Fluid supply nozzle structure for minimum quantity lubrication during high-speed milling according to claim 2, characterized by, that the adjusting rod comprises two threaded rods which are connected at one end to a common fixing adjusting tube (I-15) and at the other end each to the pipe housing (1-18) via a fixing adjusting rod screw (1-13), wherein it is further provided that the pipe housing (1-18) is an arc-shaped housing. [4] Fluid supply nozzle structure for minimum quantity lubrication during high-speed milling according to claim 1, characterized bythat the hollow tube has a larger inner diameter than the first pipe and the end of the first pipe, where it is connected to the hollow tube, is bent, wherein the first pipe has an opening with a projection into which the second pipe is inserted with a bent end, or that the end of the second pipe, where it is connected to the hollow tube, is bent, wherein the second pipe has an opening with a projection on its circumference and into which the first pipe is inserted with a bent end, further providing that the bent end of the first pipe forms an angle ε of 18°≤ε≤22° with the bent end of the second pipe. [5] Fluid supply nozzle structure for minimum quantity lubrication during high-speed milling according to claim 1, characterized by, that, in the presence of several nozzle bodies on one side of the pipe housing (1-18), a rotatable hose clamp (1-21) is arranged for adjusting the gas flow rate in the first pipe and the lubricating oil flow rate in the second pipe, the clamp projecting at one end from the pipe housing (1-18) and passing through the first pipe at the other end, the pipe housing (1-18) further comprising two pipe housing sections, each of which is provided with three nozzle bodies on one side, the angle γ of 35° ≤ γ ≤ 40° between adjacent nozzle bodies on a pipe housing section, the angle β of 2° ≤ β ≤ 5° between the two pipe housing sections, and the angle δ of between a nozzle body and the edge of the pipe housing section on which it is located 10°≤δ≤15° exists. [6] Fluid supply nozzle structure for minimum quantity lubrication during high-speed milling according to claim 1, characterized by , that it further comprises a third pipeline connected to the hollow pipe, into which water is introduced, and further provided that - the end of the first pipe, where it is connected to the hollow pipe, is bent, the first pipe having an opening with a projection on its circumference, into which both the second pipe and the third pipe are inserted with a bent end, - the first pipe has an inner diameter that is larger than the inner diameter of the second and third pipes, but smaller than the inner diameter of the hollow pipe, - the first pipeline forms an angle η of 10°≤η≤14° with both the second pipeline and the third pipeline. [7] Fluid supply system for minimum quantity lubrication in high-speed milling, comprising a fluid supply nozzle structure arranged within a box body (1-03) for minimum quantity lubrication in high-speed milling according to one of claims 1 to 6, on one side of which is an oil-water-gas-chip collection hood which is connected to an oil-water-gas-chip separation device (11-03) arranged outside the box body (1-03). [8] Fluid supply system for minimum quantity lubrication during high-speed milling according to claim 7, characterized by, that the pipe housing (I-18) is arranged in the circumferential direction of a milling cutter (I-05), wherein it is further provided that the first pipe and the second pipe pass through the box body (I-03) and are clamped by means of a common conveying pipe fastening clamp (1-09), wherein a conveying track is formed on the surface of the box body (I-03). [9] Fluid supply system for minimum quantity lubrication during high-speed milling according to claim 8, characterized by , that the oil-water-gas-chip separation device (II-03) is a semicircular vortex cyclone dust separator, at the inlet of which a cone angle α of 5°≤α≤10° is provided, wherein a collection funnel (II-04) is arranged at the lower end of the cyclone dust separator and the cyclone dust separator is attached to a support.

Images