baber/WOPTO huggingface dataset:
Patent KR-20110093700-A (KR)
Title: Nano-diamond dispersion liquid and method of manufacturing the same
Inventor: PARK TAE HEE
IPC: C09D7/61
Filed: 2011-02-10
Abstract: PURPOSE: A nano-diamond dispersing solution and a method for manufacturing the same are provided to increase the dispersibility of a solution by increasing the electrical repulsive force between nano-diamond particles using a metal hydroxide. CONSTITUTION: A nano-diamond dispersing solution is obtained by dispersing a nano-diamond, in which a particle diameter thereof is between 1 and 100nm, in a dispersing solvent. A method for manufacturing the nano-diamond dispersing solution includes the following: Nano-diamond aggregate is prepared(S10). The nano-diamond aggregate is mixed with a metal hydroxide aqueous solution to form a mixed solution(S20). The mixed solution is stabilized to be separated into supernatant and precipitate(S30). The supernatant and the precipitate are respectively extracted(S40). The supernatant is dried(S50). The supernatant is mixed with the dispersing solvent(S60).
Patent KR-20120095131-A (KR)
Title: Construction method and structure of bicycle road
Inventor: CHOI JEONG HUN
IPC: E01C15/00
Filed: 2011-02-18
Abstract: PURPOSE: A construction method and a structure of a bicycle road are provided to obtain flatness, permeability, and proper thermal conductivity by forming a precious slag ball layer. CONSTITUTION: A construction method of a bicycle is as follows. A basing floor is formed on a floor surface to be constructed as a bicycle road(S200). A two liquid type elastic material having a hardening agent and a main agent is sprayed on the top of the basic floor to for a hard elastic layer(S210). A precious slag ball layer is formed on the top of the hard elastic layer by using a precious slag ball(S220). A surface layer is formed on the top of the precious slag ball layer to have a predetermined frictional coefficient(S230). A finishing work for indicating lines or patterns is implemented if necessary(S240).
Patent KR-20120105187-A (KR)
Title: Polish rice by pounding machine
Inventor: KIM HAE SOOK
IPC: B02B3/00
Filed: 2011-03-15
Abstract: PURPOSE: A house rice swipper is provided to prevent the distribution of minute dust by installing a collecting pouch by effectively collecting the minute dust. CONSTITUTION: A house rice swipper includes a case, a speed reduction apparatus, a transportation unit, a rice swipper unit, a swiping degree control unit, a rice bran container, a rice container, and a collecting unit(107). The case includes a hopper. The operation motor and a speed reduction apparatus generate power. The transportation unit transports rice to a side direction. The rice swiping unit swipes the surface of the rice. The swiping control unit transports white rice. A rice bran case separates and collects the rice bran generating in a swiping process.
Patent KR-20120109132-A (KR)
Title: Backlight unit and method for manufacturing the same
Inventor: PARK SE YUL
IPC: B41J2/005
Filed: 2011-03-28
Abstract: PURPOSE: A backlight unit and a manufacturing method thereof are provided to automatically form reflection films on the other sides of a light guide plate except for a light incident surface of the light guide plate, thereby increasing production. CONSTITUTION: Ink is transferred on a printing pad(s15). The printing pad moves to a printing location where the printing pad faces one side of a fixed light guide plate to make one side of the printing pad faces upward(s17). The ink of the printing pad is transferred onto one side of the light guide plate(s19). A reflection film is formed. The printing pad moves to an initial position(s21). [Reference numerals] (S11) Fixing light guide plate; (S13) Filling engraved part of image plate with ink; (S15) Ink is transferred on a printing pad; (S17) Printing pad ascends and moves to a printing location; (S19) Printing pad descends and applies ink to the lateral side of the light guide plate; (S21) Printing pad moves to an initial position
Patent KR-20110046430-A (KR)
IPC: D03D23/00
Filed: 2011-04-16
Abstract: PURPOSE: A flexible electric transformer with high cooling efficiency is provided to improve cooling efficiency and reduce the volume of a transformer by forming an iron core with a textile type. CONSTITUTION: A flexible transformer is made of textile. The textile is processed with varnish resin. A weft(2) is inserted into a warp(1) by a carrier(4). The weft is formed by covering the winding on an iron core. The iron core of the weft is an iron alloy wire, a cobalt alloy wire, and a nickel alloy wire. The winding of the weft is an enamel wire.
Patent KR-20120118247-A (KR)
Title: Compressor
Inventor: AHN HEW NAM
IPC: F04B53/10
Filed: 2011-04-18
Abstract: PURPOSE: A compressor is provided to remove noise due to the foreign materials as a discharge hole is formed in a discharge lid which selectively opens and closes an outlet. CONSTITUTION: A compressor comprises a cylinder block, a housing, a valve plate(145), and a discharge lid(147). The cylinder block comprises a cylinder bore for compressing refrigerants. The housing is connected to the cylinder block, and forms a suction chamber and a discharge chamber. The valve plate comprises an inlet(145b) and an outlet(145c). The discharge lid selectively opens and closes the outlet to make compressed refrigerants discharged to the discharge chamber from the cylinder bore. The outlet and discharge lid comprise a foreign material discharge unit. The foreign material discharge unit comprises an outlet hole and a trepanned area. The trepanned area is concavely formed around the outlet connected to the discharge lid. The outlet hole is formed in the discharge lid, and connected to the trepanned area.
Patent KR-20120119281-A (KR)
Title: 4-way lumbar support assembly
Inventor: CHO CHAN KI
IPC: A47C7/40
Filed: 2011-04-21
Abstract: PURPOSE: A 4-way lumber support assembly is provided to reduce the fatigue of a driver and passengers by supporting the lumber portion of a driver and passengers. CONSTITUTION: A 4-way lumber support assembly(100) comprises a fixed wire(110), a cross wire(120), a comfort mat(130), a rotary unit(140), and a lifting unit(150). The fixed wire is installed in a seat back frame(10). The cross wire is coupled with the upper portion of the fixed wire. The comfort mat is installed in the cross wire to be rotated. The rotary unit is installed in the fixed wire. The rotary unit rotates the lower portion of the comfort mat to the lumber portion of a people. The lifting unit is installed to be separated from the fixed wire and lifts the rotary unit.
Patent KR-20120121135-A (KR)
Title: Method of manufacturing a cylindrical target for a sputter
IPC: B21C31/00
Filed: 2011-04-26
Abstract: PURPOSE: A method for manufacturing a cylindrical sputtering target is provided to manufacture a cylindrical target at low temperatures and improved productivity. CONSTITUTION: A method for manufacturing a cylindrical sputtering target comprises the steps of: preparing metal billets(10), mounting the metal billets in an extrusion die(100), and pressing the metal billets with a mandrel and a press to extrude a cylindrical target from the inlet of the extrusion die.
Patent KR-20120122162-A (KR)
Title: Electret condenser microphone with variable input impedance pre-amplifier and variable input impedance controlling method of the pre-amplifier
IPC: H03F1/56
Filed: 2011-04-28
Abstract: PURPOSE: An electret condenser microphone with a variable input impedance pre-amplifier and controlling method for a variable input impedance of the pre-amplifier are provided to regularly maintain the level and sensitivity of an input signal by increasing total impedance of an impedance part. CONSTITUTION: A digital capacitance microphone(100) comprises a microphone sensor part(10), a pre-amplifier, an A/D converter(30), and a control block(40). The microphone sensor part comprises an external signal and a condenser for a microphone. The pre-amplifier comprises an impedance part, a bias stage, and an operational amplifier. The A/D converter is formed with a delta-sigma modulator. The control block controls total impedance of the impedance part. [Reference numerals] (AA) Control block
Patent KR-20120127805-A (KR)
Title: Apparatus for automatic recovery control membrane treating water including sensor
IPC: B01D61/22
Filed: 2011-05-16
Abstract: PURPOSE: A collecting rate automatic controllable membrane filtration-based water treatment apparatus with a sensor is provided to control a collecting rate controlling part according to the polluted degree of water in a filtering bath. CONSTITUTION: A collecting rate automatic controllable membrane filtration-based water treatment apparatus includes a filtering bath(100), a first filtering part(101), a filtered bath sensor part(110), one or more second filtering parts(130), a collecting rate controlling part(160), a controlling part(140), and a controlling signal inputting unit. The filtering bath sensor part is positioned in the filtering bath and detects the polluted degree of water in the filtering bath. The second filtering parts filter the water from the filtering bath and re-supply the filtered water into the filtering bath. The collecting rate controlling part controls the amount of the water from the filtering bath. The controlling part is connected to the sensor and controls the second filtering parts and the collecting rate controlling part. [Reference numerals] (AA) Draining filtered water
Patent KR-20120128795-A (KR)
IPC: A45C11/04
Filed: 2011-05-18
Abstract: 본 발명은 렌즈를 보관하기 전 렌즈를 세척할 때 사용하는 렌즈통에 관한 것이다. 종래의 렌즈통은 단지 렌즈 보관용으로만 만들어 졌으며 보관하기 전에 세척용으로는 부족한 점이 있었다. 본 발명은 상기의 문제점을 해결하기 위한 것으로서, 본 발명의 목적은 렌즈 세척과 보관을 한꺼번에 할 수 있도록 하기 위한 것이다. 상기의 목적을 달성하기 위해서는, 일반 렌즈통보다 두배의 높이의 크기로 만들어 그 중간 높이에 구멍이 뚫린 플라스틱 막을 걸칠 수 있도록 하여 만든다. 그 플라스틱 막은 뺄 수도 있고 넣을 수도 있게 한다. 상기와 같은 본 발명에 따르면, 보관용이었던 렌즈통을 세척과 보관의 이중의 역할을 가지게 하며, 플라스틱 막은 세척할 때에만 넣는 것이기 때문에 불편한 점은 없다.
Patent KR-20120129274-A (KR)
Title: Apparatus for Tightening Skin by Thermocoagulation with Ultrasound
IPC: A45D44/22
Filed: 2011-05-19
Abstract: PURPOSE: A wrinkle removal machine using ultrasound is provided to easily remove wrinkles of face, neck, or hand by probes. CONSTITUTION: A wrinkle removal machine using ultrasound comprises transmission tranducers(13a). The transmission transducer includes one or more piezoelectric devices. The one or more piezoelectric devices generates ultrasound having the specific range of frequency. The reception transducers(13b) includes one or more piezoelectric devices. The one or more piezoelectric devices receive the ultrasound reflected from the inner body. The one or more piezoelectric element converts the ultrasound into the electric signal.
Patent KR-20120130587-A (KR)
Title: Dry-type coke extinguishing facility
IPC: C10B39/02
Filed: 2011-05-23
Abstract: PURPOSE: CDQ(Coke Dry Quenching) equipment is provided to enable uniform abrasion of inner wall bricks of a chamber around a feeding device by changing a path during charging and feeding of cokes to mix uneven cokes. CONSTITUTION: CDQ equipment comprises a chamber(100), a plurality of circulating gas supply pipes(500) which are installed in the lower side of the chamber and supply circulating gas to the chamber, and a plurality of liner covers(400) which cover the top of the circulating gas supply pipes to prevent abrasion of the circulating gas supply pipes, wherein the cross section of the liner covers is asymmetrical around the vertical axis.
Patent KR-20120138118-A (KR)
Title: Floating floor for ship
Inventor: JUNG CHOON HO
IPC: B63B29/02
Filed: 2011-06-14
Abstract: PURPOSE: A floating floor for a ship is provided to maintain the appearance of the bottom floor of a hull and to ensure the safety of crew members against fire. CONSTITUTION: A floating floor(300) for a ship comprises a steel deck(310), a vibration absorbing unit(320), a first finishing member(330), a fixing unit(400), a second viscoelastic layer(460), and a second finishing member(500). The steel deck forms the bottom of a hull. The vibration absorbing unit absorbs vibrations transferred to the floating floor by being installed in the top of the steel deck. The fixing unit fixes the first finishing unit the top of the vibration absorbing unit. The second viscous-elastic layer is installed to the upper part of the fixing unit and the first finishing member to block the transfer of the vibration and bottom impacts of the steel deck. The second sealing unit is installed on the top of the second viscoelastic layer.
Patent KR-20120138471-A (KR)
Title: Unloading arm for oil and operation method
Inventor: HWANG YOU SEONG
IPC: B67D7/78
Filed: 2011-06-15
Abstract: PURPOSE: An unloading arm for refueling and an operational method thereof are provided to be easily coupled to a tank truck by controlling the length and angle of the unloading arm according to a gap between an aircraft fuel storage tank and the tank truck. CONSTITUTION: An unloading arm for refueling comprises a fluid flow part(110), a joint part(130), and a pipe(150). The fluid flow part is connected to a tank truck to form a moving path of aircraft fuel. One side of the fluid flow part is reciprocated by a piston motion so that the length of the fluid flow part to the tank truck can be controlled. The joint part is coupled to one side of the fluid flow part to rotate the fluid flow part on a xy-plane and an xz-plane. The pipe connects the fluid flow part and the joint part to the aircraft fuel storage tank.
Patent KR-20120139273-A (KR)
Title: Apparatus and method for manufacturing microporous film for a separator of battery
Inventor: PARK HYUN CHAE
IPC: H01M50/406
Filed: 2011-06-17
Abstract: PURPOSE: A manufacturing device of microporous films for separation film of a simple battery and a manufacturing method thereof using the device are provided to stably manufacture high quality microporous films. CONSTITUTION: A manufacturing device of microporous films for separation film of a simple battery comprises the following steps: molding precursor films by extrusion molding molten material of partically crystalline resin through T-die(20); cooling the precursor film by touching frozen gas which has lower temperature than the melting point of the partical crystalline resin with the precursor film; and forming micropores on the film by stretching in one-axis direction or two-axis direction.
Patent KR-20120001616-A (KR)
Title: Led lamp system
Inventor: TERASAKA HIROSHI
IPC: H05B44/00
Filed: 2011-06-21
Abstract: PURPOSE: An LED lamp system is provided to turn on an LED element by supplying a constant current in which ripple rate is under 1.3 to the LED element from a power supply unit, thereby controlling the twinkle of the LED element. CONSTITUTION: An LED lamp system is formed into a ceiling added type lighting apparatus. The LED lamp system has a main body unit which is installed to ceiling and the reflector of an inverted triangle which is attached to the main body unit. The LED lamp system comprises a socket(14) as a pair of light source attachment means. The LED lamp system comprises a tubular type LED lamp(16) which is connected between the sockets and an exclusive electricity source(17) as a power supply unit which turns on the tubular type LED lamp.
Patent KR-20120001647-A (KR)
Inventor: KANG MOON HEE
IPC: A47K10/48
Filed: 2011-06-28
Abstract: 본 발명은 자동으로 손을 살균하고 세척하기 위한 손 세척기에 관한 것으로, 보다 상세히는 이동식으로 배치될 수 있는 소형의 구조를 갖추고, 손의 세척, 살균과 건조 과정을 하나의 기기 내에서 차례로 실행하여 대중 위생관리 기기로서 간편하게 사용할 수 있고, 위생적으로 탁월해 개인 건강관리 효과가 우수한 손 세척기에 관한 것이다.
Patent KR-20130003488-A (KR)
Title: A fixing device for standing pipe
Inventor: MOON CHOON KWANG
IPC: E03C1/12
Filed: 2011-06-30
Abstract: PURPOSE: A riser pipe fixture is provided to minimize noise between floors moving through a sleeve as a gap between the sleeve and the fixture is blocked by a partition fixing packing. CONSTITUTION: A riser pipe fixture(100) comprises a vertical pipe(101), a pipe fixing plate(102), and a fixing pipe(103). The lower part of the vertical pipe is fitted into a connecting pipe, and the length of the vertical pipe is 400-600mm. The pipe fixing plate has a larger diameter than the diameter of a sleeve to be placed on the sleeve(200). The fixing pipe protrudes from the pipe fixing plate. The lower part of a vertical pipe(400) is fitted to a stopping sill.
Patent KR-20120005992-A (KR)
Title: Depositing tungsten into high aspect ratio features
Inventor: CHANDRASHEKAR ANAND
IPC: H01L21/28
Filed: 2011-07-11
Abstract: PURPOSE: A tungsten deposition method to the inside of a high aspect ratio characteristic part is provided to charge the characteristic part with tungsten including materials, thereby arranging a seam in the inside of the charged characteristic part. CONSTITUTION: An under-layer(113) is deposited on a substrate(103). The under-layer lines a characteristic part hole(105). The under-layer arranges an overhang(115). An unfilled void(129) is arranged under a reference point(125). The size of the void and the position of the reference point are varied according to a parameter of a deposition process, the size of a characteristic part, and the size of the overhang.
Patent KR-20130010263-A (KR)
Inventor: NA JA YEOL
IPC: F16H3/44
Filed: 2011-07-18
Abstract: 본 발명은 가솔린 엔진, 디젤 엔진, 가스 엔진과 같은 엔진이나 전기모터 등으로 구동되는 다양한 종류의 차량에 적용되어 차량의 정지, 저속주행, 고속주행, 가속주행, 감속주행, 주차와 같은 각 운전조건에 따라 차량 구동시 요구되는 토크와 속도를 제어하게 되는 차량의 무단 자동변속 시스템을 제공한다. 이와 같은 본 발명에 따른 차량의 무단 자동변속 시스템은 1개의 주유성기어기구와 3개의 보조유성기어기구의 조합으로 무단자동변속부와 1개의 변속유성기어기구 및 다수의 클러치가 설치된 전후진변속부로 이루어져 무단자동변속이 구현되고, 변속모듈을 이루는 유성기어기구의 작동을 제어하기 위한 별도의 브레이크기구나 클러치기구가 설치되지 않더라도 차량의 운전자에 의해 조작되는 엑셀러레이터(accelerator)에 의해 조절되는 차량 엔진축의 회전수에 연동 되어 작동이 자동으로 제어되도록 한다.  이에 따라, 운전자의 차량 운전이 간편하고 용이하게 이루어질 수 있게 되고, 차량 운전자의 운전능력이 향상되게 된다. 이와 더불어 본 발명에 따른 차량의 무단 자동변속기 시스템은 변속을 위해 구비되는 다수개의 기어들 중에서 공회전하는 기어가 없으며, 엔진 동력을 끊어주는 클러치나 유체기계(토크컨버터)가 필요 없어짐에 따라 차량의 연비가 향상되게 된다. 특히, 차량의 토크 변화와 변속이 자동으로 유도되도록 함에 따라 차속에 따른 차량의 등판능력이 자동으로 구현됨으로써 차량 성능의 향상 및 연비가 향상되게 된다.
Patent KR-20120014884-A (KR)
Title: Snood
Inventor: PETTERSEN KURT
IPC: A01K91/04
Filed: 2011-08-10
Abstract: PURPOSE: A snood for lines, strings, and ropes for the fishing ground is provided to enable users to attach the snood to a swivel eye by using a permanent loop running knot. CONSTITUTION: A snood is applied to lines, strings, and ropes for the fishing ground, and includes loops for attaching the snood to the lines, strings, and ropes. The snood is produced with rigid nude threads, and twisted to a strand. The loops are produced by threading the end of the snood through two strands of a main body of the snood. The end of the snood is threaded through the main body of the snood more than two times in between the two strands.
Patent KR-20110110740-A (KR)
Inventor: HWANG HYUN JOO
IPC: G06Q30/02
Filed: 2011-08-11
Abstract: 본 발명의 광고정보 제공 시스템은, 단말의 요청에 대응하는 웹페이지를 통한 광고정보 제공시, 상기 단말로부터 수신된 광고제공 기록정보를 근거로 상기 광고정보가 기 제공된 광고정보인지 확인하고, 상기 확인된 광고정보가 기 제공된 광고정보인 경우, 상기 확인된 광고정보를 제외한 광고정보를 재 확인하고, 상기 수신된 광고제공 기록정보를 근거로 상기 재 확인된 광고정보가 기 제공된 광고정보인지 확인하며, 확인결과, 상기 확인된 또는 재 확인된 광고정보가 기 제공된 광고정보가 아닌 경우, 상기 광고정보가 상기 단말로 제공되어 출력되도록 처리하는것을 포함한다.
Patent KR-20130020001-A (KR)
Title: A method for measuring resolution of optical device
Inventor: KUBOTA HIDETOSHI
IPC: G01J9/00
Filed: 2011-08-18
Abstract: PURPOSE: A method for measuring the resolution of an optical device is provided to improve measuring accuracy and to obtain robust properties with respect to a measurement environment. CONSTITUTION: A method for measuring the resolution of an optical device is as follows. An angle is detected from an arbitrary target area of a test chart desired to measure the resolution(210). The detected angle data is oversampled at an unequal space(220). The oversampled data is resampled while filtering the same so that an equal space data is obtained(230). A primary difference of the equal space data is obtained(240). The intensity and a phase of frequencies are obtained by performing Fourier transformation with respect to the obtained primary difference data(250). The obtained intensity data is standardized(270). [Reference numerals] (210) Detecting an angle; (220) Oversampling; (230) Resampling while filtering; (240) Primary difference; (260) Resampling while filtering; (270) Standardizing; (AA) Start; (BB) End
Patent KR-20130020002-A (KR)
Title: Method of preparing mono disperse particle, mono disperse particle prepared by using the method, and tunable photonic crystal device using the mono disperse particle
Inventor: HAN MOON GYU
IPC: C08F2/38
Filed: 2011-08-18
Abstract: PURPOSE: A manufacturing method of a monodispersed particle is provided to easily control the particle size by controlling the content ratio of monomers in the synthesis. CONSTITUTION: A manufacturing method of a monodispersed particle comprises: a step of mixing at least two or more monomers in a solvent; a step of putting an initiator into the solvent and synthesizing at least two or more monomers by forming a copolymer-shaped particle; and a step of controlling the particle size by controlling the content ratio of the two or more monomers. The particle size is controlled within the range of 50-200 nm. The particle forms a colloid solution in a solvent. The zeta potential of the particle is (-150) - (-30) mV or +30 - +150 mV.
Patent KR-20130020945-A (KR)
Title: Compositions and methods for treating myelodysplastic syndrome
Inventor: BROWN GAIL L
IPC: A61K31/198
Filed: 2011-08-18
Abstract: PURPOSE: A composition containing ezatiostat or salt thereof is provided to treat myelodysplastic syndrome of a patient treated with a DNA methyltransferase inhibitor. CONSTITUTION: A composition for treating myelodysplastic syndrome contains ezatiostat or salt thereof. The composition is used for treating a patient with myelodysplastic syndrome, who is treated with a DNA methyltransferase inhibitor. Ezatiostat or salt thereof is used by oral administration everyday for 2 or more weeks.
Patent KR-20130021872-A (KR)
Inventor: OH MIN SOO
IPC: A01K1/015
Filed: 2011-08-24
Abstract: PURPOSE: A house for a hamster is provided to prevent foul odor and to improve the sanitation of the house by frequently replacing sawdust. CONSTITUTION: A house for a hamster comprises an outside wire net(100) which is used as the exterior wall of the house, an inside wire net(200) which is formed within the outside wire net, stairs(300) for separating a first floor from a second floor, and a bottom surface(400) on which saw dust is spread. The stairs are adhered to the outside wire net by a hinge and is movable up and down.
Patent KR-20110112262-A (KR)
Inventor: SHIN CHANG HEE
IPC: G11C17/14
Filed: 2011-08-31
Abstract: 본 발명은 읽기동작시 데이터 센싱 마진(sensing margin)을 개선시켜 동작 신뢰성을 향상시킬 수 있는 비휘발성 메모리 장치의 단위 셀 및 이를 구비한 비휘발성 메모리 장치를 제공하기 위한 것으로, 이를 위해 본 발명은 입력단과 출력단 사이의 노드와 제1 단이 연결된 안티퓨즈와, 상기 안티퓨즈의 제2 단과 접지전압단 사이에 연결된 제1 스위칭 수단을 구비하는 비휘발성 메모리 장치의 단위 셀을 제공한다.
Patent KR-20130027263-A (KR)
Title: Compressor
Inventor: YUN JE SU
IPC: F04B27/08
Filed: 2011-09-07
Abstract: PURPOSE: A compressor is provided to improve efficiency of the compressor with extending suction stalk which inhales refrigerant by installing a suction check valve of new structure in a suction chamber. CONSTITUTION: A compressor comprises a rear housing, a cylinder block, a valve assembly(150), and a valve member. The rear housing forms exterior of the compressor and includes a suction port which inhales outside refrigerant and a suction chamber which stores the refrigerant inhaled from the suction port. The cylinder block radially forms a cylinder bore(111) which compresses the refrigerant inhaled from the suction chamber. The cylinder block includes a crank chamber(121) which comprises a driving unit for compressing the refrigerant inhaled into the cylinder bore. The valve assembly is equipped between the rear housing and the cylinder block and controls the refrigerant flow between the suction chamber and the cylinder bore. The valve member is installed in the suction chamber and selectively blocks the refrigerant flow between the suction chamber and the cylinder bore by pressure difference between the crank chamber and the suction chamber.