baber/WOPTO huggingface dataset:
Patent KR-100751947-B1 (KR)
Title: Concrete structure repair-strengthen construction and thereof
Inventor: KIM HOY JUNG
IPC: E04B1/64
Filed: 2007-01-05
Granted: 2007-08-27
Abstract: A repair and reinforcement structure for a wall of a concrete structure is provided to keep watertight by cutting off a space between waterproof panels using a hydrophilic seal and a seal protective cap. The repair and reinforcement structure for a wall of a concrete structure contains a waterproof panel(100) installed on the existing concrete surface(500) by panel fixtures(400) and provided with connections(110) on an L-shaped end(110a) and a S-shaped end(110b), a seal protective cap(200) inserted between the connection and the connection to connect each waterproof panel installed on the concrete surface, and a hydrophilic seal(300) installed in the axial direction to seal up the space between the connection and the connection of adjacent waterproof panels and protected by the seal protective cap to keep watertight. The repair and reinforcement method for a wall of a concrete structure comprises the steps of: cutting a waterproof panel into the appointed size and bending one end in the appointed shape; perforating holes on a S-shaped end at regular intervals to insert panel fixtures; leveling the concrete surface and perforating holes on the concrete surface at regular intervals to fix waterproof panels; fixing the waterproof panels to the concrete surface by corresponding the holes of the waterproof panels and the holes of the concrete surface and driving in the panel fixtures; and inserting a seal protective cap between waterproof panels.
Patent KR-100859771-B1 (KR)
IPC: H01M2/20
Filed: 2007-01-17
Granted: 2008-09-24
Abstract: 축부와 상기 축부의 직경보다 넓게 형성된 헤드부를 포함하는 전지의 양극핀을 와이어를 이용하여 제조하는 전지 양극핀 제조장치가 개시된다. 전지 양극핀 장치는 상기 와이어의 상기 헤드부를 형성하는 부분이 드러나며, 상기 와이어의 상기 축부를 형성하는 부위를 클램핑하는 클램퍼와, 상기 클램퍼를 향해 타격 가능하도록 설치되며 상기 와이어와 접하는 성형면에 상기 헤드부 형상으로 요입홈이 형성된 펀치를 포함한다. 따라서, 양극핀 헤드부의 형상을 정확하게 한정하여 준 상태에서 성형을 하므로, 헤드부의 형상이 정확하게 형성된다. 
       
     리듐 전지, 양극 핀
Patent KR-101326653-B1 (KR)
IPC: H04B1/38
Filed: 2007-01-17
Granted: 2013-11-08
Abstract: 본 발명은 단말기 바디와, 단말기 바디에 내장되고 그 표면에 그라운드가 형성되는 인쇄회로기판과, 단말기 바디의 하우징과 인쇄회로기판의 그라운드를 전기적으로 연결하여 그라운드를 확장시키는 연결부와, 상기 연결부에 설치되어 직류를 차단하고 교류를 통과시켜서 상기 하우징으로 누설전류가 흐르는 것을 차단하는 캐패시터로 구성되어, 충전 중인 단말기를 사용할 때 누설전류가 단말기 하우징로 흐르는 것을 차단하여 사용자가 통전현상을 느끼는 것을 방지하면서 단말기의 무선 성능 및 정전기 성능을 유지할 수 있는 휴대 단말기를 제공한다.  
       
     휴대단말기, 누설전류, 그라운드
Patent KR-100777590-B1 (KR)
Title: A rice cake making device
Inventor: LEE JUN HANG
IPC: A23L7/10
Filed: 2007-01-19
Granted: 2007-11-28
Abstract: An apparatus for preparing tteok (rice cake) by pasting rice flour with water and steaming it is provided to minimize the volume of a heating part by using microwave. An apparatus for preparing tteok comprises a tteok siru(110) (an earthenware steamer for preparing tteok) which has an opened space part(111) for accommodating a rice flour mixed with water; a stirrer(120) which is installed in the space part to mix the rice flour mixed with water and has the connection groove(121) opened downward and a plurality of projected stirring axes(123) formed at the outer circumference; a first drive motor(130) which is installed at the lower part of the tteok siru to supply the rotation force to the stirrer and is provided with a first drive axis(131) inserted into the connection groove; a heating part(140) which irradiates microwave to steam the paste; and a cover(150) which is provided with a ventilation fan.
Patent KR-100989698-B1 (KR)
IPC: B21D37/00
Filed: 2007-01-22
Granted: 2010-10-26
Abstract: 본 발명은, 상부가 곡선으로 가공되며, 방사형으로 배치된 복수의 격판 상기 격판의 사이에 원주 방향으로 배치되어 상기 격판과 용접 조립되는 보강판 및 성형하고자 하는 판재와 동일한 곡률을 가지며, 상기 격판의 상부에 장착되는 라이더를 포함하는 방사형 격자 몰드를 제공한다.  
     본 발명은 곡면을 따라서 단일 곡률을 가지고 있으며 격자를 구성하고 있는 프레임의 상면 에지에 최종 곡률을 형성하는 라이더가 부착되고, 방사형으로 격판이 배치되며 그 사이에 원주 방향으로 보강판이 배치된 방사형 격자 몰드를 제공한다.  
       
     방사형 격자 몰드, 라이더
Patent KR-100810317-B1 (KR)
Title: Apparatus and method for controlling antenna interference in mobile phone supporting reinforcing apparatus
Inventor: PARK JEE TAE
IPC: H04B1/10
Filed: 2007-01-31
Granted: 2008-03-04
Abstract: An apparatus and a method for controlling antenna interference signals of a portable terminal supporting a reinforcing apparatus are provided to ensure optimum antenna performance with respect to interference by each band of a multiband antenna generated when the reinforcing apparatus is configured around the multiband antenna, and improve performance of the antenna by being connected through a stable antenna radiation pattern. A multiband antenna support different bands to a portable terminal. A controller generates a switching control signal so as to operate one antenna of the multiband antennas, and controls a switch(410) according to an antenna selected by the switching control signal. The switch performs switching to a path for shorting or opening(420) a reinforcing apparatus to the ground by the controller. The switch is disposed in a main board(340) for providing the ground within the portable terminal. One end of the switch is electrically connected with a main board ground pattern, and the other end is electrically connected with the reinforcing apparatus.
Patent KR-100721531-B1 (KR)
Inventor: KIM JIN SEOK
IPC: H01R24/58
Filed: 2007-02-07
Granted: 2007-05-23
Abstract: 음향 출력이 가능한 이어폰에 데이터를 전송하는 도크(Dock) 커넥터와 유에 
     스비 커넥터 내장된 복합기능 액세서리. 
     음향장치의 접속단자에 결합 되는 잭 커넥터가 연결되고 본체에 데이터를  
     전송하는 도크(Dock) 커넥터를 내장하여, 목걸이 형 또는 일반 이어폰으로 
     활용할 수 있고, 원하는 장소에서 전원 공급 및 데이터의 송수신을 실행 
     할 수 있다. 
     
     도크(Dork) 커넥터, USB, 케이블, 이어폰
Patent KR-100819743-B1 (KR)
Title: 3d structure poly-crystal compound semiconductor solid-state image sensor and a method for manufacturing the same
Inventor: HAN GUN HEE
IPC: H01L27/146
Filed: 2007-02-09
Granted: 2008-04-08
Abstract: A 3-dimensional structure poly-crystal compound semiconductor solid-state image sensor and a method for manufacturing the same are provided to maximize a light receiving area and to improve photosensitive efficiency by forming a metal electrode on a semiconductor epi layer. A signal transfer region(206) is formed on a first conductive type semiconductor substrate(205) and comprised of a second conductive-type impurity layer. A signal detection region(208) is separated from the signal transfer region and comprised of a second conductive type impurity layer. Plural metal lines(207) are electrically connected to the signal detection region. A transfer gate(204) is formed on the semiconductor substrate of a first conductive type. The transfer gate transmits charges between the signal transfer region and the signal detection region. An interlayer dielectric(210) of a first conductive type is formed on the semiconductor type semiconductor substrate including the signal transfer region, the transfer gate, and the signal detection region. A metal electrode(203) is connected to a photodiode region(209) and comprised of a vertical metal electrode(211) and a horizontal top metal electrode(212). A poly crystal compound semiconductor epi layer(202) is formed on a surface of the interlayer dielectric including the top metal electrode and becomes the photodiode region by implanting P-type and N-type impurities to realize a PN junction.
Patent KR-100884277-B1 (KR)
IPC: H04B7/14
Filed: 2007-02-14
Granted: 2009-02-18
Abstract: 본 발명은 지하시설물이나 지상시설물에 재난 재해가 발생되거나 긴급한 사고의 발생으로 인한 통신선로의 파손시 독립적으로 운영되어 통신선로의 신속한 확보를 위해 사용되는 이동용 무선 중계기에 관한 것으로; 밧데리가 내부에 설치되는 케이스와, 상기 케이스의 중앙 상측에 구비되며 한쌍의 제1 및 제2중계용 안테나가 구비되는 안테나지지대와, 상기 제1 및 제2중계용 안테나를 통해 수신되는 전파의 감도를 측정하는 전파감도측정센서와, 상기 전파감도측정센서로 부터 전파감도정보가 수신되면 그 전파감도를 정량적으로 표시해주는 디스플레이수단과, 상기 전파감도측정센서의 전파감도정보를 입력받고, 상기 디스플레이수단을 제어하는 제어판넬로 이루어지는 것을 그 기본 구성으로 한다. 
     본 발명에 따르면 지하시설물이나 지상시설물 내에서 재난 재해 또는 사고가 발생되어 통신 통신망이 무력화된 경우 전력선이 필요없이 자체적인 밧데리 전력으로 자체 구동되어 통신망을 신속하게 복구할 수 있게 하는 장점이 있다. 
       
     재해, 무선, 중계기, 통신
Patent KR-101357422-B1 (KR)
IPC: G03B5/00
Filed: 2007-02-14
Granted: 2014-02-11
Abstract: 검출한 진동에 대응한 검출 신호를 출력하는 진동 검출 센서 (51A)(51B) 와, 차단 주파수에 따라 검출 신호를 여파하는 여파부 (52A)(52B) 와, 여파부의 차단 주파수를 변경하는 제어부 (64) 를 구비하는 것을 특징으로 하는 진동 검출 장치. 
     
     진동 검출 장치, 광학 장치, 진동 검출 센서
Patent KR-100849394-B1 (KR)
Title: Plasma processing apparatus having isolator capable of adjusting height
Inventor: LEE SEUNG HO
IPC: H01L21/205
Filed: 2007-03-06
Granted: 2008-07-31
Abstract: A plasma processing apparatus having an insulating member capable of adjusting a height is provided to freely control a height of a horizontal insulating member by forming one or more taps in the horizontal insulating member. An RF(Radio Frequency) power source for plasma generation is electrically connected to an upper electrode. A lower electrode(14) is arranged to be opposite to the upper electrode. An RF power source for a bias generation is electrically connected to the lower electrode. A horizontal insulating member(24) is arranged at an upper side of an edge of the lower electrode. The horizontal insulating member includes one or more taps for controlling a height. A first vertical insulating member(26) is arranged to be adjacent to a side of the lower electrode. A second vertical insulating member(28) is arranged to be separated from the first vertical insulating member in a direction apart from the lower electrode. One or more coupling units inserted into the tap are extended toward the first vertical insulating member.
Patent KR-100746551-B1 (KR)
Title: The system and construction method to build apartment
Inventor: KIM HYUN MI
IPC: E04G11/28
Filed: 2007-03-06
Granted: 2007-08-06
Abstract: A construction method by climbing a form of a building is provided to construct a concrete wall simply and strongly by forming a steel form with a simple method using a form climbing system. The construction method by climbing a form of a building comprises the steps of: coupling a form climbing system attached with a 2-step worktable(50) using anchor bolts(11); completing a form by adhering a steel form(18) closely to a wall using a form forward/backward interlocking device of the form climbing system and adding an inner form, pouring concrete and curing a wall of the first floor; pulling out the steel form to the rear of the completed wall of the first floor using the form forward/backward interlocking device, ascending the 2-step worktable coupled with the steel form to the second floor using the form climbing system and fastening to the wall using anchor bolts; completing a form by advancing the climbed 2-step worktable and the steel form using the form forward/backward interlocking device and adhering closely to a wall and adding an inner wall steel form, pouring concrete and curing a wall of the second floor; pulling out the steel form to the rear of the completed wall of the second floor using the form forward/backward interlocking device, ascending the 2-step worktable coupled with the steel form to the third floor using the form climbing device and fastening to a wall using anchor bolts; installing 3 and 4-step worktables under the ascent 2-step worktable, advancing the steel form using the form forward/backward interlocking device and adhering closely to a wall, adding an inner form and pouring concrete, and then curing a wall of the third floor; and forming a concrete layer by ascending the steel form to the required floor by repeating above mentioned steps.
Patent KR-100856924-B1 (KR)
Title: Method and apparatus for indicating network state
Inventor: SOHN SEON GYOUNG
IPC: H04L12/26
Filed: 2007-03-08
Granted: 2008-09-05
Abstract: An apparatus and a method for displaying a network state are provided to determine an abnormal state which deteriorates the performance of a network by using information about distinct dispersion, entropy, and clustering as a result of a combination of important properties in a traffic event, and detect a harmful traffic or an abnormal traffic. A method for displaying a network state comprises the following steps of: grouping traffics according to a protocol(S100); selecting and combining three of a resource address, a resource port, a destination address, and a destination port, and calculating distinct dispersion and entropy for a remaining element(S200); displaying the calculated distinct dispersion and entropy on a security radar that an angle of a circle is divided into N and a radius of the circle is divided into M(S300); and detecting the abnormality of a network by referring to a displayed radar state and detecting and reporting a harmful traffic or an abnormal traffic which causes an abnormal state(S400).
Patent KR-100722794-B1 (KR)
Title: Glove for relieving itch and inflammation, and method for producing the same
IPC: A41D19/04
Filed: 2007-03-13
Granted: 2007-05-31
Abstract: Provided is a less irritant or inflammatory glove in which irritation and inflammation are to be reduced when using the glove made from latex, nitrile, PVC, or the like in the field of medicine, physical and chemical research, industry, or the like by utilizing antipruritic and antiinflammatory effects of phthalocyanine, but not by reducing the contents of protein ingredients contained in a latex glove as in prior art.Phthalocyanine is used as a less irritant or inflammatory agent when wearing the glove. The phthalocyanine is mixed into a raw material for an inner glove, or mixed into a raw material of the glove, or mixed into a lubricant for wearing the glove, or mixed into a coating material applied to the inside surface of the glove, or adhered to a filling implanted on the inside surface of the glove.
Patent KR-100815203-B1 (KR)
Title: Weight scale for the cargo vehicle and installation method thereof
Inventor: KIM MYUNG GYU
IPC: G01G19/02
Filed: 2007-03-13
Granted: 2008-03-19
Abstract: An axle weigher and an installation method thereof are provided to maintain balance of a Wheatstone bridge by changing a compensation resistor depending on ambient temperature, thereby improving accuracy of weighing. An axle weigher includes detection plates(52,54), a plurality of strain gauges, and temperature gauges. The detection plates are installed at left and right sides of a road(50) in the width direction. The strain gauges are installed at the upper and the lower part of the detection plates symmetrically with each other. The temperature gauges are installed on the detection plates respectively, and resistance values thereof are varied depending on ambient temperature. The strain gauges and the temperature gauges form a Wheatstone bridge to measure the load of a wheel of the vehicle on the detection plate.
Patent KR-101329628-B1 (KR)
IPC: H01L21/28
Filed: 2007-03-21
Granted: 2013-11-14
Abstract: [과제] 기판, 게이트 전극, 게이트 절연층, 소스 전극, 드레인 전극 및 유기 반도체 층을 갖는 회로 기판에 있어서, 그 오프 전류를 작게 하는 것. 
     [해결 수단] 본 발명의 회로 기판(1)은, 기판(7)과, 기판(7)의 한쪽  면측에 설치된 소스 전극(5), 드레인 전극(6) 및 게이트 전극(2)과, 그 게이트 전극(2)에 대하여 그 소스 전극(5) 및 드레인 전극(6)을 절연하는 게이트 절연층(3)과, 그 게이트 절연층(3)에 접해서 설치된 유기 반도체층(4)을 구비하고, 상기 유기 반도체층(4)이 형성되는 상기 소스 전극(5) 및 드레인 전극(6)의 사이가 되는 영역에, 저면이 상기 기판(7)의 내부 또는 기판(7) 측에 위치하는 오목부(8)을 갖고, 상기 유기 반도체층(4)의, 상기 소스 전극(5) 및 드레인 전극(6)의 사이가 되는 영역이며 상기 게이트 절연층(3)과의 계면이, 그 영역 이외의 영역의 상기 게이트 절연층(3)과의 계면보다도 상기 기판(7) 측에 설정되는 것을 특징으로 한다. 
       
     기판, 게이트 전극, 게이트 절연층, 소스 전극, 드레인 전극 및 유기 반도체 층
Patent KR-100810698-B1 (KR)
Title: Elevator for vehicle
Inventor: JUNG SUN HO
IPC: E04H6/00
Filed: 2007-03-23
Granted: 2008-03-07
Abstract: An elevator for a vehicle is provided to prevent a cage from rotating while moving vertically by having two or more pairs of guides, and to prevent the rotational movement of a cage when a cage stops for loading on a vehicle. An elevator(1) for a vehicle includes a hoistway(3), and a cage(30) installed to make a vertical movement along the hoistway, wherein the cage includes a main support plate(31) ascent or descent by a lifting device, a turntable(39) installed to be rotative against the main support plate, a rotary device rotating the turntable against the main support plate, a side wall rotating together with the turntable, and one or more inner doors(32) installed to the side wall to be opened and closed. In addition, an entrance(60) is formed to the hoistway to let a vehicle enter and leave, an outer door(65) is installed to the entrance, a connection plate(70) is installed to a gap between the cage and the hoistway and provided with a concave portion corresponding to a curvature portion of the turntable to minimize a gap between the turntable and the connection plate when the turntable neighbors to the connection plate with the rotation of the cage, and two or more pairs of guides(80) are installed to the hoistway to guide a straight portion of the turntable exposed partially from the main support plate at two sides to be restricted to prevent the rotation of the turntable while a cage is ascending or descending.
Patent KR-100910853-B1 (KR)
IPC: G11C11/407
Filed: 2007-03-29
Granted: 2009-08-06
Abstract: 본 발명은 다양한 지연고정된 클럭의 스큐를 쉽게 조절할 수 있는 지연고정루프 회로를 구비한 반도체 메모리 장치를 제공하기 위한 것으로, 이를 위해 본 발명은 지연고정동작에 의해 정해진 지연값들에 대응하여 각각 서로 다른 위상을 가지는 다수의 지연고정된 클럭을 제공하기 위한 지연고정루프 회로; 상기 다수의 지연고정된 클럭에 응답하여 데이터를 출력시키기 위한 데이터 출력회로; 상기 지연고정루프 회로와 상기 데이터 출력회로의 사이에 배치되어, 상기 다수의 지연고정된 클럭이 상기 데이터 출력회로에 전달될 때에 발생하는 클럭스큐를 제거하기 위한 스큐보정부; 및 다수의 지연고정된 클럭이 상기 데이터 출력회로에 전달될 때에 발생하는 클럭스큐를 제거하기 위해 상기 스큐보정부를 제어하는 스큐제어부를 구비하는 반도체 메모리 장치를 제공한다. 
       
     반도체, 메모리, 지연고정루프, 듀티보정, 위상감지부.
Patent KR-100878569-B1 (KR)
IPC: B21C37/06
Filed: 2007-03-30
Granted: 2009-01-15
Abstract: 본 발명은, 코팅관 제조용 기포 제거장치에 관한 것이다. 
     이는 특히, 수구와 삽구로 이루어진 코팅관의 제조시 수구측의 불규칙면에 대응되어 압착되는 서브로울러와 평면에 압착되는 메인로울러로 구성되어 수구와 삽구를 포함하는 관체 전체를 균일하게 압착하게 되는 것이다. 
       
     수구, 코팅면, 관체, 서브로울러
Patent KR-100852676-B1 (KR)
Title: Driving control apparatus of reciprocating compressor
Inventor: KIM KWANG WOOK
IPC: F04B49/12
Filed: 2007-03-30
Granted: 2008-08-19
Abstract: An operation control apparatus of a reciprocating compressor is provided to prevent breakage of an intake valve and an exhaust valve of a compressor by preventing shaking phenomenon. An operation control apparatus of a reciprocating compressor comprises a stroke estimation unit(300) for estimating stroke of the compressor when a load of the compressor is changed. An operation frequency determiner(400) calculates the phase difference between the stroke estimation value output from the stroke estimation unit and current applied to the compressor, and outputs a variable operation frequency signal so that an absolute value of the difference between the phase difference and a reference phase difference is maintained. A controller(600) varies the current operation frequency based on the variable operation frequency signal output from the operation frequency determiner.
Patent KR-100820841-B1 (KR)
Title: Clothes refreshing apparatus
Inventor: SONG JUNG TAE
IPC: D06F58/02
Filed: 2007-04-10
Granted: 2008-04-11
Abstract: A front loading washing machine is provided to increase the entire size of the washing machine actually or seemingly and to allow a user to check the inside of a drum easily. A front loading washing machine(100) comprises a cabinet(110), a drum, a front panel(111), and a door(200). The front panel forms a front side of the cabinet, having an opening to put clothes into a drum. The door selectively opens and closed the opening. The vertical length of the door is equal to or greater than the side length of the front panel. A protrusion unit is formed on at least one of the upper part and the lower part of the front panel. The protrusion unit is bent with predetermined curvature.
Patent KR-100834039-B1 (KR)
Title: Artificial turf and method of making the same
Inventor: OH TAE JOO
IPC: E01C13/08
Filed: 2007-04-12
Granted: 2008-05-30
Abstract: Artificial turf and a method of making the same are provided to prevent tufted parts of an artificial tuft pile from being damaged by employing a reinforcing fabric and a permeable elastic pad. Artificial turf comprises a foundation cloth(160), artificial turf piles(170), and a reinforcing fabric(140). The artificial turf piles are tufted on the foundation cloth at regular intervals. The reinforcing fabric is attached to the bottom surface of the foundation cloth by an adhesive(150). The adhesive is rubber powder type urethane adhesive. The reinforcing fabric is geotax. An elastic pad is attached to the bottom surface of the reinforcing fabric.
Patent KR-100834852-B1 (KR)
Title: Insert for test handler
Inventor: NA YUN SUNG
IPC: G01R31/26
Filed: 2007-04-13
Granted: 2008-06-03
Abstract: An insert for a test handler is provided to exchange a latch block simply and to recycle the latch block regardless of the size of a semiconductor device by detachably joining a latch block to an insert body. In an insert(400) for a test handler, an insert body(410) has a placing space(411) for settling a semiconductor device. At least one latch block(420) is detachably combined to the insert body to hold the placed state of the semiconductor device settled in the placing space. The insert body has a block receiving groove(412) for containing the latch block. The latch block is fitted in the block receiving groove. A hanging sill is formed on the inner wall of the block receiving groove in the insert body. A hanging pin projection(421a) to move elastically is hung to the hanging sill to prevent separation of the latch block, when the latch block is contained in the block receiving groove.
Patent KR-100781133-B1 (KR)
Title: Apparatus for video monitoring of road traffic safety institution
Inventor: PARK WON JAE
IPC: H04N7/18
Filed: 2007-04-20
Granted: 2007-11-30
Abstract: A system for video monitoring of a road traffic safety institution is provided to mount a camera and an object monitoring sensor in the road traffic safety institution and confirm collision when a vehicle hits the road traffic safety institution, thereby preventing unnecessary budget from being wasted. A system for video monitoring of a road traffic safety institution includes a camera(110), an object monitoring sensor(120), a digital video recorder(130), a solar cell panel(150), and a battery(140). The camera photographs peripheral images. The object monitoring sensor senses a distance from an object and outputs an event signal when the object is contacted. The digital video recorder stores images inputted from the camera in a storing unit. The solar cell panel is installed to be exposed to an external part in the road traffic safety institution. The battery provides driving voltage to the camera, the object monitoring sensor, and the digital video recorder.
Patent KR-100840179-B1 (KR)
Title: Impeller with fuel pump of automobile
Inventor: HWANG YONG TAEK
IPC: F04D29/38
Filed: 2007-04-23
Granted: 2008-06-23
Abstract: An impeller for a fuel pump of a vehicle is provided to prevent both end portions of a blade from being broken during rotation of an impeller. An impeller for a fuel pump of a vehicle comprises a plurality of blade grooves(30). The blade grooves are formed in an outer periphery of both sides of an impeller(10). A blade(20) having a symmetrical shape is formed in the blade groove. The blade has a rotation angle of 5° to 6° and a sectional angle of 90° to 110°, so that the efficiency of a fuel pump is raised. The blade has first and second end points at corners thereof. The end points are in contact with the blade groove. The first end point is in contact with a reference line(A). The second end point is inclined at an angle of theta in the direction inverse to the rotation direction of the impeller.