Suck back valve-Suck back valve with sucking amount control mechanism - SMC Kabushiki Kaisha

Close Window. Our iPolymer Suckback Valves are ideal for acid, solvent, photoresist solutions and other process dispensed chemistries. Our Suckback Valve incorporates the suckback feature in a Normally Closed pneumatic valve. When air pressure is removed from the valve actuator, an internal diaphragm is pushed upward which forms a vacuum in the valve body. While the valve is closing, the vacuum sucks back the final droplets of process media.

Suck back valve

Suck back valve

Suck back valve

Suck back valve

Suck back valve

The diaphragm 7, which is coupled to the piston 9, protrudes into the fluid passage 4 as shown in FIG. Valve having suck-back feature. Therefore, the pilot pressure, which is introduced into the suck back mechanism 28 by the aid of the supplying solenoid-operated valveis supplied to the diaphragm chamber Suck back valve Our Suckback Valve incorporates the Suco feature in a Normally Closed pneumatic valve. After a predetermined amount of coating liquid has been coated on the semiconductor wafer by Lovers knot earrings gold coating liquid drip apparatusmain control unit outputs a deactivating signal to the first electromagnetic Suck back valveand the first electromagnetic valve Suck back valve an OFF valvs.

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A connecting member 54 is fastened to the other end of the first piston 46 in the axial direction by the aid of a screw section. Suck back valve is inconvenient, for example, because it is necessary for the operator to appropriately adjust and reset the suction amount of the liquid sucked by the first diaphragm 8 depending on, for example, the type, the flow rate, and the viscosity of the discharge liquid to be discharged from the nozzle. USA1 en. The suck back mechanism Asian boy swimming includes a second upper valve body 76 a Acupuncture for sore muscles a second lower valve body 76 b which are integrally connected to the joint Bald cypress trees fertilizing 36and a second piston displacement member 80 which is arranged in a second chamber 78 formed in the second upper valve body 76 a and the second lower valve body 76 b and which is provided displaceably in the vertical direction. Accordingly, the second control unit b derives the deenergizing signal to the supplying solenoid-operated valve of the second electropneumatic proportional valve b to allow the supplying solenoid-operated valve to be in the OFF state, simultaneously with which the second control unit b derives the energizing signal to the discharging solenoid-operated Clip free vedio xxx to allow the discharging solenoid-operated valve to be in the ON state. Therefore, the first diaphragm 8 is moved upwardly integrally with the second diaphragm 11 and the vertically movable member 10 to a state shown by a solid line in FIG. You should have a meniscus in sight glass window before starting pump. However, the suck back valve 1 concerning the conventional technique described above is not provided with any mechanism for adjusting the displacement amount of the vertically movable member 10 which is displaced integrally with the first diaphragm 8. In this situation, the load sensorwhich is provided for the suck back mechanism 28detects the load strain amount which is applied by the pressure of the pilot pressure supplied vzlve the diaphragm chamber 96 while being pressed by the spring force of the second spring member A suck back valve comprises a suction amount-adjusting mechanism including a screw member which regulates a displacement amount of a second piston integrally displaceable with a second diaphragm in accordance with abutment of a disk-shaped member, a rotary driving section which allows the screw member to move toward or away from the disk-shaped member, and a detecting section which detects a displacement amount of the screw member. In this situation, the second control unit b counts the Shck of revolutions of the rotary driving section based on the detection signal vack from the detecting section equipped for the rotary driving section to calculate the displacement amount T of the screw member which is displaced corresponding to the number of revolutions. You may also use bback set falve two Suck back valve solenoid valves or 1 three way solenoid valve on pumps not having anti-suck back valves incorporated into the design. First and second data-setting mechanisms abwhich introduce preset signals into the first and second control units ab respectively, are connected to the first and second electropneumatic proportional valves ab respectively. Device for preventing liquid from dripping from filling nozzle of liquid filling machine.

During operation it is normally closed, and creates vacuum when switched from open back to closed position to suckback a predetermined amount of liquid.

  • The LVD series are space saving, compact type, air operated high purity valves, which are designed to overcome the harsh environments often encountered in wet process applications.
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The present invention relates to a suck back valve capable of avoiding, for example, liquid from dripping from a supply port for a pressure fluid by sucking a predetermined amount of the pressure fluid allowed to flow through a fluid passage. A suck back valve has been hitherto used, for example, in the step of producing a semiconductor wafer or the like. The suck back valve functions to avoid so-called liquid dripping which would be otherwise caused such that a minute amount of the coating liquid drips from the supply port to the semiconductor wafer when the supply of the coating liquid to the semiconductor wafer is stopped.

A suck back valve concerning such a conventional technique is shown in FIG. The suck back valve 1 has a main body 5 which is formed with a flow chamber 4 for making communication between an inflow port 2 and an outflow port 3 , and a cover 6 which is connected to an upper portion of the main body 5.

The inflow port 2 is connected to a supply source not shown for a discharge liquid, while the outflow port 3 is connected to an unillustrated nozzle. An opening 7 , which extends in the upward direction, is formed at a substantially central portion of the flow chamber 4. A first diaphragm 8 , which partitions the flow chamber 4 at the upper surface in an air-tight manner, is stretched over the opening 7. A vertically movable member 10 , which has the lower end thereof allowed to abut against the first diaphragm 8 , is arranged in an accommodating chamber 9 which is formed above the first diaphragm 8.

A second diaphragm 11 , which is interposed between the main body 5 and the cover 6 , is arranged above the vertically movable member The second diaphragm 11 and the vertically movable member 10 are integrally displaceable by the aid of a projection 12 which is caulked to the end of the vertically movable member 10 and which is secured to the second diaphragm A coil spring 13 , which urges the second diaphragm 11 upwardly, is installed between the first diaphragm 8 and the second diaphragm A pressure chamber 15 , to which the pilot air is supplied via a pilot air port 14 , is formed between the second diaphragm 11 and the cover 6.

The cover 6 is provided with a detection unit 17 comprising a detection pin 16 to make abutment against the projection 12 of the vertically movable member The operation of the suck back valve 1 concerning the conventional technique will be schematically explained below. The pressure of the pressure chamber 15 is high as the pressure is supplied from an unillustrated electropneumatic proportional valve to the pilot air port 14 during the supply of the discharge liquid.

The second diaphragm 11 is disposed at the lower position indicated by a two-dot chain line shown in FIG. The first diaphragm 8 , which is operated integrally with the vertically movable member 10 , is also disposed at the lower position, and the volume of the flow chamber 4 is decreased.

In such a situation, when the supply source for the discharge liquid is deenergized to stop the discharge from the unillustrated nozzle, then the pilot pressure supplied from the pilot air port 14 is reduced, and the pressure in the pressure chamber 15 is lowered. Therefore, the first diaphragm 8 is moved upwardly integrally with the second diaphragm 11 and the vertically movable member 10 to a state shown by a solid line in FIG. As a result, the first diaphragm 8 is deformed, and the volume of the flow chamber 4 is increased.

Accordingly, the discharge liquid contained in the nozzle is sucked. In this arrangement, the deformation of the first diaphragm 8 corresponds to the vertical movement of the vertically movable member 10 , which is detected as the movement of the detection pin 16 of the detection unit A detection signal is derived from the detection unit 17 to an unillustrated instruction unit to perform feedback control.

However, the suck back valve 1 concerning the conventional technique described above is not provided with any mechanism for adjusting the displacement amount of the vertically movable member 10 which is displaced integrally with the first diaphragm 8.

Therefore, the conventional suck back valve is inconvenient in that it is not possible to arbitrarily set the suction amount of the discharge liquid contained in the nozzle corresponding to the displacement amount of the vertically movable member This is inconvenient, for example, because it is necessary for the operator to appropriately adjust and reset the suction amount of the liquid sucked by the first diaphragm 8 depending on, for example, the type, the flow rate, and the viscosity of the discharge liquid to be discharged from the nozzle.

A general object of the present invention is to provide a suck back valve capable of arbitrarily adjusting and resetting the suction amount of the liquid to be sucked by a suck back mechanism. With reference to FIG. The joint section 24 includes a joint body 36 which has a first port 32 a formed at one end and a second port 32 b formed at the other end and which is provided with a fluid passage 34 for making communication between the first port 32 a and the second port 32 b , inner members 38 which are engaged with the first port 32 a and the second port 32 b respectively and which are inserted into openings of the tubes 22 a , 22 b respectively, and lock nuts 40 which retain liquid tightness or air tightness of connecting portions of the tubes 22 a , 22 b by being screwed into screw grooves which are engraved at the ends of the joint body As shown in FIG.

A first seal member 48 is installed to a connecting portion between the first upper valve body 42 a and the first lower valve body 42 b. Air tightness is retained for the first chamber 44 by means of the sealing action of the first seal member A valve plug 52 , which closes the fluid passage 34 by being seated on a seat section 50 , is screwed to one end of the first piston 46 in the axial direction.

The valve plug 52 is composed of a thick-walled section which is disposed at a central portion, and a thin-walled section which is formed integrally at a circumferential portion of the thick-walled section.

A connecting member 54 is fastened to the other end of the first piston 46 in the axial direction by the aid of a screw section. A first diaphragm 56 is interposed at a connecting portion between the first piston 46 and the connecting member The first diaphragm 56 is formed to be thin-walled having a flat plate shape with its circumferential edge portion being interposed between the first upper valve body 42 a and the first lower valve body 42 b.

An O-ring 58 and a packing 60 having a V-shaped cross section are installed to annular grooves on the outer circumferential surface of the first piston 46 respectively. A cylinder chamber 62 , which is closed by the first diaphragm 56 in an air-tight manner, is formed under the first diaphragm The pressure fluid acts on a flange section 46 a which is formed at an upper portion of the first piston 46 to press the first piston 46 in the upward direction.

Therefore, the connecting member 54 , the first piston 46 , and the valve plug 52 are moved upwardly in an integrated manner under the flexible bending action of the first diaphragm 56 , and thus the valve plug 52 is separated from the seat section 50 to effect the switching from the valve-closed state to the valve-open state see FIG.

A first spring member 70 , which has one end fastened to the flange section 54 a of the connecting member 54 and which has the other end fastened to an annular step 68 of the first upper valve body 42 a , is provided in the first chamber The first spring member 70 is provided so that the connecting member 54 , the first piston 46 , and the valve plug 52 are pressed downwardly by the spring force of the first spring member A magnet 72 is installed to a recess disposed at one end of the connecting member The flange section 54 a abuts against the wall surface 66 of the first upper valve body 42 a , and thus the flange section 54 a functions as a stopper to regulate the upward movement of the first piston A position detection sensor 74 , which is composed of, for example, a Hall element to detect the position of the first piston 46 , is provided for the first upper valve body 42 a opposed to the magnet 72 while being separated by a predetermined spacing distance.

In this embodiment, the position detection sensor 74 detects the magnetic field of the magnet 72 installed to one end of the connecting member The suck back mechanism 28 is arranged on the joint section 24 disposed closely to the second port 32 b.

The suck back mechanism 28 includes a second upper valve body 76 a and a second lower valve body 76 b which are integrally connected to the joint body 36 , and a second piston displacement member 80 which is arranged in a second chamber 78 formed in the second upper valve body 76 a and the second lower valve body 76 b and which is provided displaceably in the vertical direction.

A second seal member 86 is installed to a connecting portion between the second upper valve body 76 a and the second lower valve body 76 b. Air tightness of the second chamber 78 is retained by the sealing action of the second seal member A second diaphragm flexible member 88 is connected to one end of the second piston 80 in the axial direction by a screw section.

The second diaphragm 88 is composed of a thick-walled section which is disposed at a central portion, and a thin-walled section which is formed integrally at a circumferential portion of the thick-walled section. A disk-shaped member 90 is fastened by a screw section to the other end of the second piston 80 in the axial direction.

A thin-walled third diaphragm 92 having a flat plate shape is interposed between the second piston 80 and the disk-shaped member The third diaphragm 92 has a circumferential edge portion interposed between the second upper valve body 76 a and the second lower valve body 76 b. An O-ring 94 is installed to an annular groove on the outer circumferential surface of the second piston A diaphragm chamber 96 , which is closed by the third diaphragm 92 in an air-tight manner, is formed over the third diaphragm An annular groove , which has a diameter larger than the diameter of the second piston 80 , is formed below the third diaphragm A second spring member , which is fastened by a flange section to press the second piston 80 in the upward direction, is arranged in the annular groove Therefore, the disk-shaped member 90 and the second piston 80 are displaced in an integrated manner in the downward direction against the spring force of the second spring member to a state in which the bottom surface of the thick-walled section of the second diaphragm 88 slightly protrudes toward the fluid passage A suction amount-adjusting mechanism , which adjusts the displacement amount of the second piston 80 that is displaceable integrally with the second diaphragm 88 , is provided above the disk-shaped member The suction amount-adjusting mechanism is composed of, for example, a stepping motor.

The suction amount-adjusting mechanism includes a rotary driving section driving mechanism which is integrally equipped with a detecting section detecting mechanism such as an encoder, and a screw member stopper member which is engraved with a male thread screwed to a screw hole of the second upper valve body 76 a. The detecting section may be constructed separately from the rotary driving section A groove , which is engaged with a rotary shaft a of the rotary driving section , is formed on one end surface of the screw member in the axial direction.

A stopper section , against which the disk-shaped member 90 makes abutment to regulate the displacement thereof, is formed on the other end surface. In this arrangement, one end of the rotary shaft a of the rotary driving section is loosely fitted into the groove of the screw member with a minute clearance. The screw member is provided displaceably in the vertical direction of the screw hole in accordance with the transmission of the rotary motion of the rotary shaft a.

In this arrangement, the number of revolutions of the rotary driving section is detected by the detecting section , and a second control unit controls the rotary motion of the rotary driving section based on a detection signal derived from the detecting section as described later on.

Accordingly, it is possible to position the stopper section of the screw member at a predetermined position. The suck back valve 20 according to the embodiment of the present invention is basically constructed as described above. Next, its operation, function, and effect will be explained. The suck back system comprises first and second electropneumatic proportional valves a , b which are constructed substantially identically and which output pneumatic pressure signals corresponding to inputted electric signals.

First and second data-setting mechanisms a , b , which introduce preset signals to the first and second control units a , b respectively, are connected to the first and second electropneumatic proportional valves a , b respectively.

Unillustrated MPU microprocessor unit , which functions as respective mechanisms of control, judgment, processing, calculation, and storage, is provided for each of the first and second control units a , b.

The detection signal of the position detection sensor 74 is introduced into the first control unit a. A coating liquid supply source , in which the coating liquid is stored, is connected to the tube 22 a communicating with the first port 32 a of the suck back valve On the other hand, a coating liquid-dripping apparatus , which is provided with the nozzle for dripping the coating liquid to the unillustrated semiconductor wafer, is connected beforehand to the tube communicating with the second port 32 b.

After performing the preparatory operation as described above, the pressure fluid supply source is energized in the initial state shown in FIG.

The first control unit a derives the energizing signal to only the supplying solenoid-operated valve based on the preset signal to allow the supplying solenoid-operated valve to be in the ON state. In this situation, the discharging solenoid-operated valve is deenergized, which is in the OFF state. During this process, the magnetic field of the magnet 72 installed to one end of the first piston 46 is detected by the position detection sensor The position detection signal, which is derived from the position detection sensor 74 , is introduced into the first control unit a.

On the other hand, the second control unit b derives the energizing signal to only the supplying solenoid-operated valve based on the preset signal to allow the supplying solenoid-operated valve to be in the ON state. Therefore, the pilot pressure, which is introduced into the suck back mechanism 28 by the aid of the supplying solenoid-operated valve , is supplied to the diaphragm chamber The disk-shaped member 90 and the second piston 80 are displaced downwardly against the spring force of the second spring member to a state in which the second diaphragm 88 slightly protrudes toward the fluid passage 34 see FIG.

The coating liquid is dripped onto the semiconductor wafer by the aid of the coating liquid-dripping apparatus As a result, a coating film not shown having a predetermined film thickness is formed on the semiconductor wafer. Accordingly, the supply of the coating liquid to the semiconductor wafer is stopped to interrupt the dripping state of the coating liquid from the nozzle of the coating liquid-dripping apparatus to the semiconductor wafer. In this situation, the coating liquid just before dripping onto the semiconductor wafer remains in the nozzle of the coating liquid-dripping apparatus Therefore, liquid dripping may occur undesirably.

Accordingly, the second control unit b derives the deenergizing signal to the supplying solenoid-operated valve of the second electropneumatic proportional valve b to allow the supplying solenoid-operated valve to be in the OFF state, simultaneously with which the second control unit b derives the energizing signal to the discharging solenoid-operated valve to allow the discharging solenoid-operated valve to be in the ON state. Therefore, the supply of the pilot pressure to the diaphragm chamber 96 of the suck back mechanism 28 is stopped, and the pressure of the pilot pressure in the diaphragm chamber 96 is decreased to be zero.

Accordingly, the second piston 80 is moved upwardly under the action of the spring force of the second spring member In this situation, the disk-shaped member 90 , which is displaced integrally with the second piston 80 , has the upper surface section which abuts against the stopper section of the screw member Accordingly, the upward displacement is regulated see FIG.

Therefore, the second diaphragm 88 , which is connected to one end of the second piston 80 , is displaced integrally, and thus negative pressure action is generated.

Model does not exist, please email cad smcusa. Select values from the drop down lists or make appropriate selections to configure the part number. Although certain preferred embodiments of the present invention have been shown and described in detail, it should be understood that various changes and modifications may be made therein without departing from the scope of the appended claims. Click for automatic bibliography generation. Back Outdoor Power Equipment.

Suck back valve

Suck back valve. You are here

Configuration: Part Number. Product Options Select Product Options Select values from the drop down lists or make appropriate selections to configure the part number. Red conflict with another selected option value. Product Catalog Series Catalog. Locate a Distributor Access eTools. Create An Account. Cancel Login. You will not hurt the pump running them all the time. Make sure the oil level is maintained in high pressure low vacuum systems or operation. Manually bring the system to atmospheric pressure before turning off pump.

Procedures to maintain systems at vacuum and shut off the pump. Install 2 manual 2 way valves. One to close system to maintain pressure the second to vent the pump inlet to atmospheric pressure before stopping pump. Install 1 manual 3 way valve. When closing system to vacuum pressure it automatically vents the pump inlet to atmospheric pressure. Install 1 2 way "normally open" solenoid valve between pump and system. This is okay, but oil may still end up between pump and start of solenoid valve and may cause problems unless inlet sees atmospheric pressure on start up.

Many of this type setup are in use today with success in this configuration. Solenoid should be rated for high vacuum.

We carry 2 way solenoids for many of the pumps. Install 2 2 way solenoid valves one "normally open" between pump and system. One "normally closed" between pump and atmospheric pressure.

The "normally closed" valve can be small in size. Install 1 3 way solenoid valve that vents pump to atmosphere at the same time closing system off to maintain pressure. This can cause pressure loss on the system due to general time lag in closing and opening the common port. Of all the solutions outlined we feel the best are either 1.

The one I would consider for cost, performance and flexibility is option 3. It was fine yesterday. If the pump is locked and will not start, vent pump inlet or system to atmospheric pressure. Check to make sure that there are not "huge" amounts of oil in your vacuum system. If so, the vacuum pump may now be low on oil.

Leave the pump off when actuating, just turn pump off and on a couple times till it looks like it might run ok. Check the oil level again. If still low turn off pump go to step C. Go to step C. Can you see the oil level meniscus in sight glass? Check the oil level if you can not see meniscus in sight glass window. The oil level is either to low or too high. You should have a meniscus in sight glass window before starting pump. Don't worry it is non-toxic at least ours is. Get an old disposable rag handy, watch your clothes, this could get ugly.

Place the rag bunched up and held loosely over exhaust port of pump. Wrap the rag around the base of exhaust dome if installed. This is to help keep things clean. With pump inlet open to atmospheric pressure turn pump on. If it does not actuate, try again. Try again. For belt drive pumps remove beltgaurd and with inlet open manual actuate pump using pulley.

Under normal operation the pump should operate freely, it may make a low gurgling sound and it may create oil mist smoke or oil droplets from the exhaust port of pump.

(주)엠 아이 – Anti-Suck Back Valve

High purity chemical valves, series LVC with integral fittings eliminate the possibility of residual liquid in pipe threads. In addition, the body has been designed for smooth flow with minimal internal dead space.

Special diaphragm construction insures gentle opening and closing preventing the formation of micro-bubbles. A unique guide ring on the piston rod eliminates lateral motion of the poppet, increasing seal life and reducing particle formation. Model does not exist, please email cad smcusa. High purity suck back valve Body types: single; unit type with 2-way valve Withstand pressure: 1 MPa Operating pressure: 0 to 0. Configuration: Part Number.

Product Options Select Product Options Select values from the drop down lists or make appropriate selections to configure the part number. Red conflict with another selected option value. Product Catalog Series Catalog. Locate a Distributor Access eTools.

Create An Account. Cancel Login. Select values from the drop down lists or make appropriate selections to configure the part number. Options in: Gray are not compatible with other selected option value.

Suck back valve

Suck back valve