102results about How to "Avoid water resistance" patented technology

The object of the present invention is to provide a particle board which is improved at its entirety in the resistance to water without impairing its performance as a bearing board member and provide a method of making the particle board. A particle board of the invention having wooden materials coated with an adhesive of a thermosetting resin and pressurized with being heated, the particle board comprising: a core layer and face layers provided on both, front and back, sides of the core layer, wherein the wooden materials of the face layer are smaller in the average particle diameter than the wooden material of the core layer; and voids between the adjacent wooden materials in the face layer and the core layer are filled with resin particles of a thermoplastic resin by being pressurized with being heated.

The invention relates to a halogen-free intumescent flame retardant wire / cable insulating material composition. The formula of the materials of the composition is as follows: 60 to 80 percent by mass of polyolefin; 15 to 35 percent by mass of halogen-free intumescent flame retardant; 2 to 10 percent by mass of synergist; 1 to 10 percent by mass of compatilizer; 0.1 to 1 percent by mass of lubricant; and 0.1 to 1 percent by mass of antioxidant. Compared with the prior art, the composition has the advantages that: dosage is low, the flame-retardant property is high, no harmful substances are released and the color cannot be changed in the process of processing and use, and precipitation resistance and water resistance are good. The composition has good flame-retardant property and toughness, and is particularly suitable for use in the fields of wires / cables, electronics / electricity, house decoration, automobile industry and the like which have strict requirement on flame retardance.

A method for manufacturing the following device is provided: an electro-optical device which includes a pair of substrates holding a display material having optical properties varied by electric stimulation and which has a curved shape. The method includes covering the front and rear faces of a display with a pair of protective films and then bonding end portions of the protective films to each other with an adhesive containing a thermoplastic resin, the end portions being located outside the display; heating the bonded end portions to melt the adhesive and then bending the display depending on applications; and solidifying the melted adhesive by cooling to allow the protective films to hold the display bent.

The invention discloses a method for controlling the remote communication of an intelligent electric power terminal as well as a module and a terminal. The method comprises the following steps: automatically detecting, by an embedded communication module, the intensity of various communication signals such as satellite communication signals, GPRS, 3G and 4G wireless communication signals and the like, judging whether the preferred signal intensity satisfies a preferred communication threshold value condition or receiving a control instruction, selecting a specific signal as the preferred signal, and completing the electric power transmission and data transmission of a power distribution network intelligent field station devices and terminals. An embedded hot-plug communication module of another embodiment integrates a Beidou circuit and a GPRS circuit, two or more signals can be received simultaneously, the electric power measurement in remote areas and signal instable regions and theacquisition and communication of a power distribution management signal can be realized. In the case of automatically detecting and preferring an economical tariff channel, an economical tariff channel can be used for a power supply enterprise to select.

The invention discloses a puffed demersal crucian carp mixed feed. The puffed demersal crucian carp mixed feed comprises, by weight, raw materials including fish meal 3-10 parts, pig meat powder 4-8 parts, corn protein powder 5-8 parts, insect protein powder 2-5 parts, fermented soybean meal 3-6 parts, soybean meal 15-20 parts, rapeseed meal 15-25 parts, cottonseed meal 5-15 parts, DDGS 6-15 parts, flour 15-20 parts, soybean oil 1.5-3 parts, monocalcium phosphate 2-3 parts, bentonite 1-3 parts, lysine hydrochloride 0.2-0.4 part, DL-methionine 0.05-0.2 part, choline chloride 0.05-0.1 part, decavitamin premix 0.3-0.6 part, vitamin C phosphate-35% 0.02-0.04 part, composite mineral substance premix 1.0-2.0 parts, taurine 0.01-0.03 part and inositol 0.01-0.03 part. The cost and coefficient of the feed are remarkably reduced, and pollution is reduced.

The invention discloses a novel straw insulation board, and the straw insulation board is prepared from the following raw materials in parts by weight: 40-80 parts of straw, 5-20 parts of epoxy glue, 1-10 parts of univalent dihydric phosphate powder, 3-20 parts of metallic oxide powder, 0.5-5 parts of borate powder, 3-6 parts of jade powder, 8-12 parts of pearlite, 5-10 parts of modified kaolin and 30-50 parts of water. The straw insulation board comprises a core material layer and a cladding layer, the core material layer is mainly prepared by press-forming the epoxy glue, the jade powder, the pearlite and the straw, the surface cladding layer is obtained by mainly uniformly cladding an inorganic cementing material with an adhesion effect on the surface layer of the straw board, and therefore, the novel straw insulation board using the straw as a board is obtained. The novel straw insulation board has excellent performances of fast forming, preserving heat and insulating, flame retarding, mould proofing and high strength, and has a clear market prospect whether being applied to the building field or other related fields in future.

The invention provides a ground-effect vehicle capable of shallowly diving, which can dive shallowly to hide water-jet propulsion and rise over the sea surface to increase jet propulsion, changes hydrofoils into airfoils, generates ground effect, flies over sea or very closely to the ground, and lands in a jet traveling manner. A multistage double circular-arc gear high pressure large capacity pump or multistage internal serial connection dual-charging double circular-arc gear pump is taken as the hydraulic propeller pump during the shallow diving process and the jet propeller pump during the process of flying over the sea. A water pump is used for water inlet submergence and water drainage to a ballast water tank besides water jet; when jet flow is performed at the tail part, and one side is shut off, namely, steering is realized; when flying over the sea, the ground-effect vehicle is still closely stuck to the sea surface for water-jet propulsion. The jet propeller pump can be used for jet propulsion at the tail part and jet hovering at the bottom part through a valve, and the jet at the tail part is turned, so that the purpose of changing the heading can be achieved. The ground-effect vehicle has four navigation conditions: main water-jet shallow diving; main water-jet and jet flying over the sea; minor jet flying near the ground; and minor jet traveling wheel landing, and the ground-effect vehicle is manufactured by manly adopting a novel light material, for example, the fiber reinforced composite material (FRP).

A UV-cured aqueous plastic coating comprises a polyurethane acrylate prepolymer, an active diluent, a light initiator, a levelling agent, a dispersant, an antifoaming agent, and deionized water, wherein the active diluent is hexanediol diacrylate. The active diluent (hexanediol diacrylate) has a very good osmotic swelling effect on polyurethane acrylate prepolymer and increases the adhesion force of the plastic coating on a plastic plate. Without any emulsifier, UV cured aqueous plastic coating having the advantages of small particle size, high stability, good film-forming property and high adhesiveness can be obtained, and thus the shortage that waterproof property and stability of plastic coating are influenced by a conventional emulsifier is overcome. The invention also provides a preparation method of the UV cured aqueous plastic coating.

The invention discloses a packaging structure for an ultraviolet luminous diode. The packaging structure for the ultraviolet luminous diode comprises a TO type metal pipe seat with a plurality of pipe feet and a metal pipe cap, wherein a luminous chip emitting ultraviolet light is arranged on the metal pipe seat, and a positive electrode and a negative electrode of the luminous chip are respectively welded on a positive electrode pipe foot and a negative electrode pipe foot of the metal pipe seat through wires. The metal pipe cap is fixed on the metal pipe seat, a light-transmitting window body is arranged on the metal pipe cap, and the light-transmitting rate is greater than 50 percent at an ultraviolet band. The packaging structure for the ultraviolet luminous diode is stable and, strong in anti-interference capacity, and has the advantages of being good in air tightness, firm in structure and the like. Good protection, anti-oxidation and water-proof functions for the ultraviolet luminous chip can be achieved, and therefore normal use of ultraviolet light sources utilizing the packaging structure in any environmental condition is practically ensured, the problem of aging of devices due to packaging materials is avoided, and service life of the ultraviolet luminous diode is prolonged.

A method for manufacturing the following device is provided: an electro-optical device which includes a pair of substrates holding a display material having optical properties varied by electric stimulation and which has a curved shape. The method includes covering the front and rear faces of a display with a pair of protective films and then bonding end portions of the protective films to each other with an adhesive containing a thermoplastic resin, the end portions being located outside the display; heating the bonded end portions to melt the adhesive and then bending the display depending on applications; and solidifying the melted adhesive by cooling to allow the protective films to hold the display bent.

The invention belongs to the technical field of on-line cleaning for central air-conditioning condensers, and in particular relates to an on-line cleaning system and a cleaning method for the central air-conditioning condenser. The on-line cleaning system for the central air-conditioning condenser comprises the condenser, a ball and water separation device, a high-pressure pump, a base and a ball collection and driving device, wherein the ball collection and driving device and the high-pressure pump are fixed on the base; the high-pressure pump is connected with the ball collection and driving device; and the condenser is connected with the ball collection and driving device through the ball and water separation device. By the on-line cleaning system and the cleaning method for the central air-conditioning condenser, the high-pressure pump is used as motive power for driving rubber balls; the rubber balls are driven by high-pressure jet flow to run, so that damage of a blade wheel and a valve of a water pump to the cleaned balls is avoided; the on-line cleaning system is provided with the ball collection and driving device, so that water resistance caused by a reason that the cleaned balls stay in cooling circulation water and on the inner surface of a filter net of the ball and water separator is avoided; and the consumption of cooling water circulation driving energy is effectively reduced.

The invention discloses an agriculture straw regeneration fire-proof heat preservation plate material. The agriculture straw regeneration fire-proof heatpreservation plate material comprises raw materials, by weight, 60-80 parts of agriculture straw, 10-15 parts of binder, 3-6 parts of metal oxide, 3-7 parts of water-proof agent, 3-5 parts of fire retardant, 15-20 parts of modified kaolin, 12-18 parts of white cement and 20-26 parts water. The agriculture straw regeneration fire-proof heat preservation plate material has the excellent properties of rapid prototyping, heat insulation and heat preservation, inflaming retarding, mould proof, deliquescence resistance, high strength and the like, the plate material is divided into a pressed inner core and an outer surface coating layer, the problems of being prone to breaking billet, sticking plate and demoulding are solved, continuous production is achieved, and the production efficiency is improved greatly; and meanwhile, the source of the main raw materials of the agriculture straw regeneration fire-proof heat insulation plate material is wide, the cost is low, the technology is simple and clear, and the high practical value and the good application prospect are achieved.

The invention discloses a preparation method for aluminum-containing continuous silicon nitride fibers. The method includes the steps that 1, air curing treatment is performed on aluminum-containing polycarbosilane fibers; 2, nitrogenization is performed on the aluminum-containing infusible polycarbosilane fibers under the atmosphere of pure ammonia gas or a nixed atmosphere of ammonia gas, nitrogen gas and argon gas; 3, high-temperature sintering is performed under the atmosphere of nitrogen gas or argon gas. The aluminum-containing continuous silicon nitride fibers prepared through the method solve the problem that B2O3 volatilization happens on B-containing continuous silicon nitride fibers at the temperature above 1500 DEG C in an aerobic environment, holes are formed, and consequently the strength of the fibers is sharply reduced; compared with a precursor method, the problems that materials are not resistant to water and air and prone to decomposition are solved, and the aluminum-containing continuous silicon nitride fibers have better high temperature resistance and high-temperature oxidation resistance; in addition, the preparation process and equipment are simple, the cost is low, and industrial volume production is easy to achieve.

An organic Si-F water-proofing agent is composed of solvent and the organic Si-F resin prepolymer which is prepared from one or more alkyl siloxane coupling agents and hydroxy F-Si oil through catalytic hydrolysis reaction. Its preparing process is also disclosed. Its advantages are high water-proofing effect and high resistance to solvent, acid, alkali and ageing.

The invention relates to a far-infrared functional master batch, a far-infrared polyester fiber as well as a preparation method and application. The far-infrared polyester fiber comprises 100 parts byweight of PET (Polyethylene Terephthalate) and 1-5 parts by weight of the far-infrared functional master batches. The far-infrared polyester fiber is capable of sufficiently taking respective advantageous properties of PET and PETG (Polyethylene Terephthalate Glycol) fibers, has excellent bending elasticity resilience and high volume fluffiness, and meanwhile has excellent anion release properties and far-infrared radiation performance, and excellent bacterium prevention and inhibition properties as well.

The invention relates to a production method of breathable leather. The condition that in a production method of the breathable leather, environment pollution in the production process is free and the problem of product breathability is available can be solved at present can not be splved. The production method comprises the following steps: (1) preparing a sizing agent, wherein the sizing agent consists of polyurethane resin and color chips in a weight ratio of 100:1.2, and the viscosity of the sizing agent is adjusted to be 1500cps; (2) mounting release paper onto a PU (Polyurethane) production line, firstly, drying the release paper at 100 DEG C, subsequently coating the release paper with the sizing, and furthermore, drying at 140 DEG C so as to obtain a half-finished product; (3) printing a dry method surface layer of the release paper with patterns and glossiness by using a three-edition printing machine; (4) compounding the release paper with a piece of base cloth by using a binding agent; and (5) washing in water by using a graining machine; and (6) inspecting to be qualified to obtain a breathable leather product. By adopting the production method, the product breathability can be solved.

The invention relates to a far infrared functional master batch, a polyester fiber and application of the master batch. The master batch is mainly prepared from the following components in parts by weight: 100 parts of PETG fibers and 20-40 parts of a far infrared ceramic material, wherein the far infrared ceramic material contains the following components in parts by weight: 5-10 parts of tourmaline, 10-15 parts of vermiculite, 5-10 parts of medical stone, 15-20 parts of kaolin, 8-15 parts of alumina, 0.5-1 part of zirconia and 0.1-0.5 part of yttria. The master batch has relatively good anion and far infrared effects and the advantage of easiness in processing and can be directly blended with traditional textile fibers, so that the problems that the durability and washing resistance arepoor because traditional effective components with the far infrared function are formed on the fiber in a surface packaging manner are solved, and the durability and washing resistance of the polyester fiber can be improved.

The present invention provides a card support automatic ejection device and a method with the use of the card support automatic ejection device. The card support automatic ejection device comprises a card support, a card seat, a motor eccentric gear, and a PCB, wherein the card support is fixed on the card seat, the card seat and the motor eccentric gear are matched and are arranged on the PCB, the motor eccentric gear is matched with the gap of the bottom of the card support, and thus the motor eccentric gear moves to a position to eject the card support. Through arranging the motor eccentric gear on the PCB, when the card taking icon on a mobile terminal is triggered, the motor eccentric gear starts to move, and the motor eccentric gear is matched with the gap between the card support and the bottom of the card seat in rotation. When the motor eccentric gear moves to a position, the card support is automatically ejected under the effect of the motor eccentric gear, thus the card support can be taken out without manually using an ejector pin by a user, and the faults of card support jam, abnormal noise and the like in the lever part rotation process are avoided.

The invention discloses oil-proof paper and a preparation method thereof and belongs to the technical field of packaging paper products. The preparation method comprises the steps: adding chitosan andbiopolysaccharide xanthan gum to obtain an antibacterial active agent, wherein the antibacterial active agent plays a role in inhibiting the growth and propagation of bacteria and spores and forms anantibacterial layer on the surface of the oil-proof paper, so that the antibacterial effect of the oil-proof paper is improved; adding cassava starch, carrying out starch modification by using octenyl succinic anhydride under an alkaline condition, adding soybean protein isolates, and meanwhile, compounding a soybean protein isolate membrane with sodium alginate polysaccharide to form an oil-proof membrane due to the low oxygen permeability of the soybean protein isolate membrane under a low-humidity condition; and carrying out graft modification on hydrolyzed collagen by taking the hydrolyzed collagen as a raw material as well as styrene and butyl acrylate as modified monomers to form a gluing active agent, wherein the gluing active agent is used for blocking a part of grease from beingpermeated into base paper of kraft paper to form double oil-proof layers, so that the oil-proof performance is improved. By using the oil-proof paper, the problem of poor oil-proof property existing in a raw material of current oil-proof paper is solved.

The invention discloses a magnetic ferric oxide desulfurizer and a preparation method thereof. The preparation method comprises the following steps that 1, ferric oxyhydroxide, a binder and an auxiliary are mixed to be uniform, and a mixture I is obtained, wherein the auxiliary adopts coal ash and / or volcanic ash; 2, the mixture I, peptizer and water are mixed to be uniform, and a mixture II is obtained; 3, the mixture II is formed and dried; 4, baking is conducted on a dried forming composition, and the magnetic ferric oxide desulfurizer is obtained. The prepared magnetic ferric oxide desulfurizer has a porous structure and is high in mechanical strength and capable of making full contact with sulfur-containing gas, and the desulfurization efficiency is improved. Desulfurization can be conducted under the working conditions of room temperature to medium temperature, normal pressure to high pressure, high hydrogen sulfide content, high moisture content and different feed gases, in the desulfurization process, the strength of a desulfurizing agent is not reduced, argillation and hardening phenomena do not exist, and the high desulfurization activity is kept all the way.

The invention discloses an underwater traction pulley type anthropopathic mechanical hand, which comprises a palm body, a thumb body, an index finger body, a middle finger body, the third finger body, a little finger body and a wrist joint, wherein the palm body comprises a shell in a shape like a Chinese character ''tu'' and same three U-shaped brackets. The long edge side of the shell in the shape like the Chinese character ''tu'' is respectively connected with the three U-shaped brackets. The index finger body, the middle finger body and the third finger body which are same in structure and distributed uniformly at an interval are respectively connected with the U-shaped brackets. The thumb body is connected with an end face of a groove of the shell in the shape like the Chinese character ''tu'' close to one side of the index finger body. The little finger body is connected with a side face of the groove of the shell in the shape like the Chinese character ''tu'' close to one side of the third finger body. The wrist joint is connected with a short edge side face of the shell in the shape like the Chinese character ''tu''. According to the invention, the weight of the fingers is lightened, the size of the fingers is reduced, and the accumulated error of transmission is reduced through transmission of the traction pulley. Mechanical parts are simpler in design so that the manufacturing cost of the parts is lowered. The misgiving about waterproof and anti-creep performances of the mechanical hand is avoided, and the reliability of the mechanical hand is improved, so that the underwater traction pulley type anthropopathic mechanical hand is suitable for underwater operation.

The invention relates to a compressed air driven metering device of a tail gas purification after-treatment system of an internal combustion engine. The compressed air driven metering device adopts compressed air to directly drive liquid, and comprises two liquid cavities, wherein the compressed air is alternately supplied to the two liquid cavities through an air control valve, so that the liquid in the liquid cavities is pushed and squeezed to a metering valve and is released by the metering valve; when one liquid cavity supplies the liquid to the metering valve, the other liquid cavity is replenished with the liquid, so that the two liquid cavities alternately supply the liquid to the metering valve uninterruptedly; and the pressure of the same air source for driving the liquid in the liquid cavities is further reduced to carry the liquid released by the metering valve to a nozzle, and then the liquid is sprayed into an exhaust pipe of the engine. The compressed air driven metering device is simple in structure, reliable, durable, insensitive to a working medium and low in cost, can resist the influence caused by the fluctuation of the air source pressure on the metering accuracy more easily compared with all the other metering devices, and can be integrated in a reactant storage box to save the mounting space and solve the problems about water resistance, dust prevention, sealing, freeze protection, anti-crystallization and the like.

The invention discloses a quick connector device for a flexible medium-voltage cable. The device comprises a middle socket and two cable terminal plugs, wherein one ends of the two cable terminal plugs are respectively connected to the ends of the two cables, and the other ends of the two cable terminal plugs are detachably connected to the two ends of the middle socket respectively. According tothe quick connector device, through the two cable terminal sockets and the middle socket, a standardized cable connector is achieved, and a connection between a ring main unit and the cable becomes very convenient and efficient; compared with a traditional copper pigtail connection mode, the connection speed of the connector device is increased by tens of times, a problem that the connection efficiency is low in the traditional mode is effectively solved, the on-site rapid connection is realized, the all-weather working environment is adapted, the efficiency of installation and power transmission can be effectively improved, a user complaint rate can be reduced, the connector is normalized, and the device adapts to connections of the cables of different manufacturers and is easy to installand convenient to match.

The invention relates to a pouring type phase change energy storage asphalt concrete pavement material and a preparation method thereof, the pavement material comprises a phase change grouting material and a matrix asphalt mixture with gaps, the matrix asphalt mixture accounts for 70%-90% by mass, and the phase change grouting material accounts for 10%-30% by mass. In the preparation process, a cement-based phase change grouting material or a resin-based phase change grouting material is poured into the matrix asphalt mixture, vibration is applied to the surface of the matrix asphalt mixture in the pouring process, the surface is cleaned after pouring is completed, and the pouring type phase change energy storage asphalt concrete pavement material is obtained after maintenance. The phase change material is used for the asphalt pavement in a pouring form, so that the phase-change material and the asphalt mixture play a role in temperature adjustment while being separated in space, the pouring type phase change energy storage asphalt concrete pavement material does not need to be stirred at high temperature and high mechanical force in the whole preparation process, the influence ofthe phase change material on the performance of the mixture is reduced, and the phase-change material utilization rate is high.

The invention discloses an environment-friendly interior wall formaldehyde removal styrene-acrylic emulsion as well as a preparation method and a coating thereof. The emulsion is prepared from the following components in parts by weight: 100 parts of deionized water, 30-35 parts of styrene, 40-45 parts of acrylate, 10-15 parts of methacrylate, 1.5-3 parts of alkyl acrylic acid, 1-5 parts of an acrylic acid functional monomer, 0.5-5 parts of an aldehyde removal functional monomer, 0.1-0.5 part of a functional crosslinking monomer, 1-5 parts of an emulsifier, 0.5-3 parts of an initiator, 0.05-1part of a buffer agent, 0.1-0.5 part of a residual monomer treatment initiator and 1-4 parts of a rapid aldehyde removal aid. The preparation method is simple in technological operation and good in controllability. The emulsion prepared through the preparation method is stable in particle size, good in performance and low in cost, integration of rapid formaldehyde removal and long-term formaldehyde removal of an interior wall coating system is achieved, and the excellent formaldehyde removal effect is achieved.

The invention provides a liquid band-aid and a preparation method thereof. The liquid band-aid consists of a film-forming agent, a solvent and bio-active glass. According to an embodiment, the liquidband-aid provided by the invention has functions of preventing wound infection, protecting wounds and water-proofing; and the liquid band-aid is applicable to protection of scratched and surgically sutured sites, skin allergy, scratched hangnails, cracks, chapped skin, small tool marks, scratched parts due to mosquito bites, rapid removal of blood crusts, scars and the like.

The invention provides a waterproof USB socket, which comprises a plug member, a metal housing sleeving the plug member, waterproof glue filling in the tail portion of the plug member, and a waterproof ring sleeving the metal housing. The plug member comprises a metal middle plate, first and second terminal groups arranged at the upper and lower sides of the metal middle plate respectively, and aninsulation body for enabling the metal middle plate and the first and second terminal groups to be fixedly integrated. The insulation body comprises a base portion, a step portion extending forward from the base portion, and a butting portion formed by extending forward from the step portion. The metal housing comprises a metal inner shell with a seamless peripheral wall. A stop member is inserted on the base portion of the insulation body. The stop member comprises a spot welding platform and an abutting-against portion formed on the front end surface of the base portion by bending forward from the spot welding platform and extending downward. The spot welding platform of the stop member is contacted with the metal inner shell and the two are integrated through spot welding. The invention also provides a manufacturing method of the waterproof USB socket.

The invention discloses a dewatering well plugging structure with water and a construction method thereof. The lower end of a steel sleeve of the plugging structure extends into the upper end of a dewatering pipe. The outer wall of the steel sleeve is connected with a lower wing ring plate and an upper wing ring plate. The portions, at the positions of the lower wing ring plate and the upper wingring plate, of the inner wall of the steel sleeve are connected with a lower water stopping ring plate and an upper water stopping ring plate which are each in an annular plate shape correspondingly.The dewatering pipe is internally filled with clay or gravel. The portion, above the clay or gravel, of the steel sleeve is internally provided with an inflatable bag. The top face of the inflatable bag is located above the lower water stopping ring plate. The transverse center line of the inflatable bag is located below the lower water stopping ring plate. A steel cover plate is welded to the upper water stopping ring plate. The contact faces between the upper water stopping ring plate and the steel cover plate form a full weld structure. The portion, between the steel cover plate and the inflatable air bag, of the steel sleeve and the portion, above the steel cover plate, of the steel sleeve both internally filled with expanding impermeable concrete. The top layer of the expanding impermeable concrete is a tongue-and-groove joint undergoing roughening treatment. The dewatering well plugging structure with water is easy to operate, wide in application range and good in plugging effect, stops a water body from rising, and improves the well plugging waterproof effect.

The invention provides a method for measuring thickness of foam plastic. The method comprises steps as follows: (1), a probe of an eddy current thickness measurement instrument is put on a surface of the foam plastic; (2), pressure is exerted according to a use requirement of the probe; (3), the thickness of the measured foam plastic is obtained according to a number displayed on a reading dial of a host of the eddy current thickness measurement instrument. The method solves the problem that the foam plastic is damaged during thickness measurement with a conventional foam plastic thickness measurement method.

The invention provides a device for polishing the back face of a semiconductor wafer, and belongs to the field of wafer manufacturing. The device comprises an operating mechanism, wherein the operating mechanism comprises a rotatable mounting disc, and the mounting disc is provided with a plurality of mounting holes. The number of bearing discs is the same as that of the mounting holes, the bearing discs are rotationally arranged in the mounting holes, a plurality of counter bores are formed in the bearing discs circumferentially, and connecting parts are arranged at the bottoms of the bearing discs. A first driving part is located below the mounting disc and comprises a driving pump, a driving shaft is movably arranged in the axis direction of a rotating shaft of the driving pump, and when the wafer is polished, the driving shaft is connected with the connecting parts of the bearing discs. A feeding mechanism comprises an alignment table and a suction cup. A grinding mechanism is arranged above the mounting disc corresponding to the first driving component, the grinding mechanism is provided with a grinding disc, and sealing covers are arranged at the positions, corresponding to the grinding mechanism, above and below the mounting disc. The device is high in use safety, convenient to maintain and check and high in machining efficiency.