Thin film sheet fabrication method

A thin film sheet manufacturing apparatus includes: an extruder; a cooling water tank; a dehydration tank; a dehydrator; and a winder for winding the thin film sheet passing the dehydrator, wherein the dehydrator includes: a support frame extending back and forth; a transferring roller; upper and lower air blowing pipes; an air blower connected to the upper and lower air blowing pipes to supply air of high pressure to the upper and lower air blowing pipes; and support rollers disposed in front of the upper and lower air blowing pipes for supporting the thin film sheet to be supplied between the upper and lower air blowing pipes.

CROSS REFERENCE

This application claims foreign priority under Paris Convention to Korean Patent Application No. 20-2013-0009821, filed 28 Nov. 2013, with the Korean Intellectual Property Office.

BACKGROUND

The present invention relates to a thin film sheet manufacturing apparatus which can manufacture a thin film sheet of a thin synthetic resin or a thin rubber material.

Recently, high-powered electronic products of various kinds, such as smart phones, monitors of various kinds, and televisions, have been developed and widely used.

In the meantime, because such electronic products have been thinner and thinner, a thin film sheet of a thin synthetic resin material is inserted into the electronic product, so as to secure insulating properties between substrates or various components and to serve a buffering function to absorb impact applied to the substrates or various components.

In this instance, the thin film sheet is made of a silicon material which is flexible and elastic, and has a thickness of about 0.4 mm.

Meanwhile, because silicon which is used as a raw material for such a thin film sheet is not environment-friendly and tears easily, methods for manufacturing thin film sheets using synthetic resin of different kinds including rubber which is environment-friendly and has high strength have been studied, but the conventional thin film sheet manufacturing apparatus has a problem in that it is difficult to make rubber into a thin film sheet form.

Moreover, recently, because such electronic products have been thinner and thinner, consumers demand thin film sheet products which have a thickness of less than 0.4 mm, but the conventional thin film sheet manufacturing apparatus has a problem in that it cannot manufacture products of the thickness of less than 0.4 mm.

Therefore, a new method to solve the above problem is needed.

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior arts, and it is an object of the present invention to provide a thin film sheet manufacturing apparatus of a new structure which can manufacture a thin film sheet using rubber.

To accomplish the above object, according to the present invention, there is provided a thin film sheet manufacturing apparatus including: an extruder for extruding rubber or synthetic resin to mold a thin film sheet of a strip type; a cooling water tank of a box form of which upper side is opened, the cooling water tank storing cooling water therein to water-cool the thin film sheet extruded in the extruder; a dehydration tank of a barrel shape of which upper side is opened, the dehydration tank having a punched plate, which is arranged inside the dehydration tank and has a plurality of drain holes perforating the upper and lower sides thereof in order to remove moisture stained on the thin film sheet passed the cooling water tank; a dehydrator for second removing the moisture stained on the thin film sheet passing the dehydration tank; and a winder for winding the thin film sheet passing the dehydrator, wherein the dehydrator includes: a support frame extending back and forth; a transferring roller which is disposed on the support frame and driven by a driving motor to transfer the thin film sheet; upper and lower air blowing pipes which are disposed in front of the transferring roller to be located at the upper and lower sides of the thin film sheet and have air vents formed in the circumferential surface and opened toward the thin film sheet; an air blower connected to the upper and lower air blowing pipes to supply air of high pressure to the upper and lower air blowing pipes; and a plurality of support rollers which are disposed in front of the upper and lower air blowing pipes for supporting the thin film sheet to be supplied between the upper and lower air blowing pipes.

Moreover, an air vent of the upper air blowing pipe faces the lower side of the front and an air vent of the lower air blowing pipe faces the upper side.

Furthermore, the transferring roller is formed in a cylindrical shape having an inner space part and includes a plurality of suction holes formed in the circumferential surface thereof, and an intake device connected to one side of the transferring roller, such that the thin film sheet is adsorbed onto the circumferential surface of the transferring roller by vacuum pressure generated when the inside air of the transferring roller is discharged by the intake device.

Additionally, the thin film sheet manufacturing apparatus further includes an anti-spattering plate upwardly extending to be inclined from the rear side of the upper air blowing pipe toward the front.

In addition, the thin film sheet manufacturing apparatus further includes a hot air drier which is disposed to face the front to blow hot air toward the lower side of the thin film sheet passing the dehydrator.

Moreover, the thin film sheet manufacturing apparatus further includes a thickness adjusting unit disposed between the extruder and the cooling water tank to adjust a thickness of the thin film sheet extruded in the extruder, wherein the thickness adjusting unit includes: a support frame; a pair of press rollers which are disposed on the support frame to get in contact with the front and rear sides of the thin film sheet extruded from the extruder and are operated by a driving motor; an interval adjusting unit which is connected to the press rollers to adjust an interval between the press rollers; and an interval measuring unit for specifying the interval between the press rollers. Each of the press rollers is formed in a cylindrical shape having an inner space part, and cooling means is connected to the press rollers to cool the press rollers by circulating cooling water to the inside of the press rollers.

As described above, the thin film sheet manufacturing apparatus cools the thin film sheet extruded by the extruder using the cooling water tank, and winds the thin film sheet using the winder after dehydrating using the dehydration tank and the dehydrator, thereby manufacturing the thin film sheet using the rubber material.

In this instance, the dehydrator includes: a support frame extending back and forth; a transferring roller which is disposed on the support frame and driven by a driving motor to transfer the thin film sheet; upper and lower air blowing pipes which are disposed in front of the transferring roller to be located at the upper and lower sides of the thin film sheet and have air vents formed in the circumferential surface and opened toward the thin film sheet; an air blower connected to the upper and lower air blowing pipes to supply air of high pressure to the upper and lower air blowing pipes; and a plurality of support rollers which are disposed in front of the upper and lower air blowing pipes for supporting the thin film sheet to be supplied between the upper and lower air blowing pipes, thereby effectively removing moisture stained on the upper and lower sides of the thin film sheet by spraying air of high pressure to the upper and lower sides of the thin film sheet transferred to the rear by the transferring roller in a state where the thin film sheet is supported by the support rollers.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Reference will be now made in detail to the preferred embodiments of the present invention with reference to the attached drawings.

FIGS. 1 to 11illustrate a thin film sheet manufacturing apparatus according to a preferred embodiment of the present invention, showing how to manufacture a thin film sheet1which is made of a rubber material and is 2 mm in thickness.

In this instance, rubber for manufacturing the thin film sheet1is thermoplastic synthetic rubber which is made by mixing synthetic materials of various kinds to natural rubber.

Moreover, as shown inFIG. 1, the thin film sheet manufacturing apparatus includes: an extruder (A) for molding a thin film sheet1of a strip type by extruding rubber; a thickness adjusting unit (B) for adjusting thickness of the thin film sheet1extruded in the extruder (A); a cooling water tank (C) for water-cooling the thin film sheet1which passes the thickness adjusting unit (B) after being extruded in the extruder (A); a dehydration tank (D) for removing moisture stained on the thin film sheet1passed the cooling water tank (C); a dehydrator (E) for second removing the moisture stained on the thin film sheet1passing the dehydration tank (D); and a winder (F) for winding the thin film sheet1passing the dehydrator (E).

In detail, as shown inFIG. 2, the extruder (A) includes: a cylinder11extending back and forth and having an inlet11aand an outlet11bwhich are respectively formed at the front and rear ends; an extruder screw12which is disposed inside the cylinder11and rotated by a driving motor12ato pressurize and transfer rubber supplied to the inlet11ato the front; a heater13which is disposed on the circumferential surface of the cylinder11to heat the rubber transferred to the front by the extruder screw12; and a mold14which is disposed at the outlet11band has a molding hole14aformed vertically for passing the rubber extruded to the outlet11bby the extruder screw12.

In this instance, the molding hole14ais long in the lateral direction and has the anteroposterior width corresponding to the thickness of the thin film sheet1, namely, the width of 0.2 mm.

Therefore, in a state where the heater13and the driving motor12aare operated, when synthetic rubber, which is a raw material, is put into the inlet11a, the rubber is pressurized and transferred to the front by the extruder screw12while being heated by the heater13, is molded in the form of the thin film sheet1while passing through the molding hole14aof the mold14, and then, is discharged to the downside.

As shown inFIGS. 3 to 5, the thickness adjusting unit (B) includes a support frame20, a pair of press rollers31and32which are disposed on the support frame20to get in contact with the front and rear sides of the thin film sheet1extruded from the extruder (A) and are operated by a driving motor36; an interval adjusting unit40which is connected to the press rollers31and32to adjust an interval between the press rollers31and32; and an interval measuring unit50for specifying the interval between the press rollers31and32.

Each of the press rollers31and32is formed in a cylindrical shape which is long in the lateral direction and has an inner space part, and is rotatably joined to the support frame20by a rotary shaft33extending laterally from the central portion of both sides, and includes a fixed press roller31fixed to the support frame20and a variable press roller32joined to the support frame20to be able to slide back and forth.

In this instance, support blocks34which are joined to the support frame20to be able to slide back and forth are rotatably joined to both ends of the rotary shaft33disposed at the variable press roller32.

Furthermore, a sprocket37which is connected to the driving motor36by a chain37ais disposed at one end of the rotary shaft33of the fixed press roller31, and a pair of gears35which are geared with each other are disposed at the other end of the rotary shaft33of the fixed press roller31and the variable press roller32, such that the fixed press roller31and the variable press roller32are interlocked with each other to be rotated in the opposite direction to each other when the fixed press roller31is driven by the driving motor36.

In this instance, the fixed press roller31and the variable press roller32are rotated in a direction that the proximate surface lowers.

Additionally, cooling means38is connected to the press roller31and32to cool the press rollers31and32by circulating cooling water to the inside of the press rollers31and32.

For this, as shown inFIG. 5, the rotary shaft33at the side that the gear35is disposed from the press rollers31and32has outer support pipes33aand33barranged to form a concentric axis, and the cooling means38includes a water supply pipe38aconnected to the inner support pipe33aby a rotary coupler and a drain pipe38bconnected to the outer support pipe33bby the rotary coupler.

In this instance, the water supply pipe38ais connected to a water supply source which supplies cooling water of room temperature, such as tap water, such that cooling water introduced into the press rollers31and32through the inner support pipe33acools the press rollers31and32and is discharged to the outside through the drain pipe38b.

The interval adjusting unit40includes: a pair of screw shafts41which are disposed to extend back and forth and screw-coupled to the support frame20and of which front end is rotatably connected to the support block34; and handles42respectively disposed at base parts of the screw shafts41.

Therefore, when a user rotates the screw shafts41in the forward and backward directions using the handles42, as shown inFIG. 3, while the support block34and the variable press roller32are moved forwardly and backwardly, the interval between the fixed press roller31and the variable press roller32is adjusted.

The interval measuring unit50includes: a support bar51rotatably joined to the support frame20in the vertical direction; and a micrometer52which is disposed at the support bar51and has a contact pin52aprotruding to one side and getting in contact with the circumferential surface of the variable press roller32.

Therefore, in a state where the circumferential surfaces of the fixed press roller31and the variable press roller32come into contact with each other by the interval adjusting unit40and the micrometer52of the interval measuring unit50comes into contact with the circumferential surface of the variable press roller32, the user sets the micrometer52to zero, and then checks a measured value of the micrometer52while separating the circumferential surface of the variable press roller32from the circumferential surface of the fixed press roller31in order to accurately adjust the interval between the variable press roller32and the fixed press roller31.

In addition, as described above, after the interval between the press rollers31and32is adjusted and the driving motor36is operated to cool the press rollers31and32using the cooling means38, when the thin film sheet1extruded from the extruder (A) passes between the press rollers31and32, the thickness of the thin film sheet1is adjusted to become the same thickness as the interval between the press rollers31and32while both sides of the thin film sheet1is compressed by the press rollers31and32.

In this instance, because the press rollers31and32are cooled by the cooling means38while temperature of the thin film sheet1extruded from the extruder (A) is so high, the thin film sheet1is first cooled while passing between the press rollers31and32.

As shown inFIG. 6, the cooling water tank (C) is formed in a box shape of which upper side is opened and stores cooling water therein, and the thin film sheet1passing the thickness adjusting unit (B) is cooled while passing the cooling water tank (C) in such a way as to be submerged in the cooling water.

In this instance, a driving roller61is disposed at the rear end part of the cooling water tank (C).

The driving roller61is formed in a bar shape of a silicon material, is rotatably joined to a supporter62disposed at one side of the rear end part of the cooling water tan (C), and the driving motor63is connected to one side of the driving roller61.

Moreover, a pair of guide bars64are disposed inside the cooling water tank (C) and arranged to be submerged in water stored in the water tank, such that the thin film sheet1is submerged in water after passing the lower side of the guide bar64.

Therefore, when the thin film sheet1passing the cooling water tank (C) is arranged to pass the lower side of the guide bar64and the upper side of the driving roller61, the thin film sheet1is stuck on the circumferential surface of the driving roller61by moisture. When the driving motor63is operated, the driving roller61pulls the thin film sheet1, such that the thin film sheet1is cooled while passing the cooling water contained in the cooling water tank (C) and is supplied to the dehydration tank (D).

As shown inFIG. 7, the dehydration tank (D) is formed in a barrel shape of which upper side is opened, and has a punched plate71, which is arranged inside the dehydration tank (D) and has a plurality of drain holes71aperforating the upper and lower sides thereof, and a drain hole (not shown in the drawings) formed at one side thereof.

Therefore, while the thin film sheet1passing the cooling water tank (C) passes the upper side of the punched plate71, moisture stained on the thin film sheet1is first removed.

As shown inFIGS. 8 to 12, the dehydrator (E) includes: a support frame81extending back and forth; a transferring roller82which is disposed on the support frame81and driven by a driving motor82ato transfer the thin film sheet1; upper and lower air blowing pipes83and84which are disposed in front of the transferring roller82to be located at the upper and lower sides of the thin film sheet1and have air vents83aand84aformed in the circumferential surface and opened toward the thin film sheet1; an air blower85connected to the upper and lower air blowing pipes83and84to supply air of high pressure to the upper and lower air blowing pipes83and84; and a plurality of support rollers86and87which are disposed in front of the upper and lower air blowing pipes83and84for supporting the thin film sheet1to be supplied between the upper and lower air blowing pipes83and84.

The transferring roller82has an inner space part, is formed in a cylindrical shape elongated in the lateral direction, and is connected to the driving motor82athrough a sprocket82band a chain82cjoined to a rotary shaft82f.

In this instance, as shown inFIGS. 8 and 9, the transferring roller82has a plurality of suction holes82dformed in the circumferential surface thereof and an intake device88connected to one side thereof.

For this, the transferring roller82includes an exhaust hole82eformed at one side, and the intake device88is connected to the exhaust hole82ethrough a suction pipe88aso as to suck the inside air of the transferring roller82and discharge the sucked air to the outside.

In this instance, the exhaust hole82eis formed in the rotary shaft82fof the transferring roller82.

Therefore, when the inside air of the transferring roller82is discharged out using the intake device88, the outside air is sucked to the inside of the transferring roller82through the suction holes82d. After that, when the thin film sheet1is put on the upper circumferential side of the transferring roller82, the thin film sheet1is adsorbed onto the circumferential surface of the transferring roller82by vacuum pressure generated while the outside air is sucked to the inside of the transferring roller82through the suction holes82d.

Furthermore, when the transferring roller82is operated by the driving motor82a, the thin film sheet1is pulled and transferred to the winder (F) disposed at the rear.

As shown inFIGS. 10 and 11, the upper and lower air blowing pipes83and84are respectively formed in a cylindrical shape extending in the lateral direction and are respectively located on the upper and lower sides of the thin film sheet1pulled by the transferring roller82.

In this instance, the air vent83aof the upper air blowing pipe83faces the lower side of the front to blow air toward the upper side of the thin film sheet1to be inclined toward the front.

Furthermore, the air vent84aof the lower air blowing pipe84is opened toward the upper part to blow air toward the lower side of the thin film sheet1in the vertical direction.

The air blower85is disposed on the support frame81and connected to the sides of the upper and lower air blowing pipes83and84through an air supply pipe85ain order to supply air of high pressure to the upper and lower air blowing pipes83and84.

As shown inFIG. 8, the support rollers86and87are disposed on the support frame81to be freely rotated while being separated from each other back and forth at a predetermined interval, and includes: a plurality of front support rollers86which support the lower side of the thin film sheet1; and a plurality of rear support rollers87located at the rear of the front support rollers86to support the upper side of the thin film sheet1.

Therefore, the thin film sheet1is arranged in such a way as to pass the upper side of the front support rollers86and the lower side of the rear support rollers87, pass between the upper and lower air blowing pipes83and84and pass the upper side of the transferring roller82. When the intake device88and the air blower85are operated while the transferring roller82is operated, the thin film sheet1passes between the upper and lower air blowing pipes83and84while being pulled backwardly by the transferring roller82. After that, as illustrated by the dotted line ofFIG. 11, by the air of high pressure discharged from the air vents83aand84aof the upper and lower air blowing pipes83and84, the thin film sheet1vibrates back and forth to remove moisture stained on the upper and lower sides and is transferred to the winder (F).

In this instance, an anti-spattering plate89upwardly extending to be inclined toward the front is disposed at the rear side of the upper air blowing pipe83in order to prevent that moisture spattering out from the thin film sheet1spatters and is stained on the thin film sheet1passing the dehydrator (E) again when moisture stained on the thin film sheet1is removed by the upper and lower air blowing pipes83and84.

As shown inFIG. 8, the winder (F) is disposed above the rear side of the support frame81, and includes: a side plate91disposed on the upper side of the support frame81; a winding drum92which is rotatably joined to the side plate91to wind the thin film sheet1on the circumferential surface by being driven by the driving motor92a; and a hot air drier93which is located below the winding drum92to blow hot air toward the lower side of the thin film sheet1passing the dehydrator (E).

The hot air drier93has a heater disposed inside the air blowing pipe mounted in the air blower.

Therefore, in a state where the thin film sheet1is fixed to the winding drum92, when the driving motor92aand the hot air drier93are operated, the thin film sheet1passing the dehydrator (E) is wound on the winding drum92, and in this instance, moisture remaining on the thin film sheet1is additionally removed by air of high temperature discharged from the hot air drier93.

As described above, the thin film sheet manufacturing apparatus cools the thin film sheet1extruded by the extruder (A) using the cooling water tank (C) and winds the thin film sheet1using the winder (F) after dehydrating using the dehydration tank (D) and the dehydrator (E), thereby manufacturing the thin film sheet1using the rubber material.

In this instance, the dehydrator (E) includes: a support frame81extending back and forth; a transferring roller82which is disposed on the support frame81and driven by a driving motor82ato transfer the thin film sheet1; upper and lower air blowing pipes83and84which are disposed in front of the transferring roller82to be located at the upper and lower sides of the thin film sheet1and have air vents83aand84aformed in the circumferential surface and opened toward the thin film sheet1; an air blower85connected to the upper and lower air blowing pipes83and84to supply air of high pressure to the upper and lower air blowing pipes83and84; and a plurality of support rollers86and87which are disposed in front of the upper and lower air blowing pipes83and84for supporting the thin film sheet1to be supplied between the upper and lower air blowing pipes83and84, thereby effectively removing moisture stained on the upper and lower sides of the thin film sheet1by spraying air of high pressure to the upper and lower sides of the thin film sheet1transferred to the rear by the transferring roller82in a state where the thin film sheet1is supported by the support rollers86and87.

Particularly, the air vent83aof the upper air blowing pipe83faces the lower side of the front and the air vent84aof the lower air blowing pipe84faces the upper part, such that the air discharged from the upper air blowing pipe83is inclinedly sprayed toward the front of the upper side of the thin film sheet1and the air discharged from the lower air blowing pipe84is vertically sprayed toward the lower side of the thin film sheet1.

Therefore, the airs sprayed from the air vents83aand84aof the upper and lower air blowing pipes83and84are sprayed in the direction that they cross each other so that the thin film sheet1is vibrated in the vertical direction, thereby more effectively removing moisture stained on the upper and lower sides of the thin film sheet1.

Furthermore, the transferring roller82is formed in the cylindrical shape having the inner space part and includes the suction holes82dformed in the circumferential surface thereof and the intake device88is connected to the transferring roller82, such that the thin film sheet1is adsorbed onto the circumferential surface of the transferring roller82by vacuum pressure generated when the inside air of the transferring roller82is discharged by the intake device88. Therefore, the thin film sheet manufacturing apparatus according to the preferred embodiment of the present invention can effectively prevent that the thin film sheet1slips from the circumferential surface of the transferring roller82.

That is, because the thin film sheet1on which moisture is stained is put on the upper side of the driving roller61, the thin film sheet1is adhered to the driving roller61by moisture, and hence, the thin film sheet1does not slip from the circumferential surface of the driving roller61when the driving roller61is operated.

On the contrary, the thin film sheet1from which moisture is removed while the thin film sheet1passes the dehydrator (E) is put on the circumferential surface of the transferring roller82. In this instance, in a case that the thin film sheet1is simply put on the circumferential surface of the transferring roller82, there occurs a slip between the transferring roller82and the thin film sheet1when the transferring roller82is operated, and hence, the thin film sheet1is not pulled to the rear.

However, according to the present invention, because the transferring roller has the suction holes82dand the intake device88is connected to the transferring roller82, the thin film sheet1gets in close contact with the circumferential surface of the transferring roller82by vacuum pressure, thereby preventing that there is a slip between the transferring roller82and the thin film sheet1when the transferring roller82is operated and effectively pulling and transferring the thin film sheet1to the rear using the transferring roller82.

Additionally, the anti-spattering plate89upwardly extending to be inclined toward the front is disposed at the rear side of the upper air blowing pipe83in order to effectively prevent that moisture spatters and is stained on the thin film sheet1passing the dehydrator (E) again when moisture stained on the thin film sheet1is removed by the dehydrator (E).

Moreover, the hot air drier93for blowing hot air to the lower side of the thin film sheet1passing the dehydrator (E) is disposed on the winder (F) in order to heat the thin film sheet1from which moisture is first removed while passing the dehydrator (E).

Therefore, the thin film sheet manufacturing apparatus according to the preferred embodiment of the present invention perfectly remove moisture remaining on the thin film sheet1, thereby effectively preventing the thin film sheet1on which moisture stained from being adhered onto the winder (F) or from being discolored or damaged by moisture.

Furthermore, the thickness adjusting unit (B) for adjusting the thickness of the thin film sheet1extruded by the extruder (A) is disposed between the extruder (A) and the cooling water tank (C) in order to readjust the thickness of the thin film sheet1extruded in the extruder (A), such that the thin film sheet1can be manufactured very thin to be less than 0.4 mm in thickness.

That is, in the case that the thin film sheet1is manufactured through the steps of extruding rubber using the extruder (A) and discharging the extruded rubber through the molding hole14aof the mold14, the thickness of the thin film sheet1discharged through the molding hole14abecomes irregular and thicker than the width of the molding hole14aby elasticity of the rubber material.

Therefore, when the thin film sheet1manufactured by the extruder (A) is readjusted in thickness using the thickness adjusting unit (B), the thin film sheet1can be very thin and have an accurate thickness.

In this embodiment, it is exemplified that the thin film sheet1dried after passing the dehydrator (E) is simply wound by the winder (F), but the winder (F) may further include a supply roll on which a tape which is combined with the thin film sheet1is wound in such a way that the tape released from the supply roll is combined with the thin film sheet1and the thin film sheet1of which one side is combined with the tape is wound on the winder (F).

Additionally, it is illustrated in the drawings that the cooling means38includes the water supply pipe38aconnected to the inner support pipe33aby the rotary coupler and the drain pipe38bconnected to the outer support pipe33bby the rotary coupler, but the cooling means38may be changed to have one of various structures, for instance, may be constructed in such a way as to be connected to the press rollers31and32to lower temperature of cooling water using a radiator or a cooling cycle while circulating the cooling water.

In addition, it is illustrated that the thin film sheet manufacturing apparatus according to the present invention manufactures the thin film sheet1using rubber, but may manufacture the thin film sheet1using various materials, such as silicon.