公开(公告)号：JPS63248978A

公开(公告)日：1988-10-17

申请号：JP8179987

申请日：1987-04-02

Applicant: NAT AEROSPACE LAB

Inventor： HAYAKAWA YUKIO

IPC: F03H1/00

Abstract: PURPOSE:To improve the ion generating performance by arranging a magnet having a reduced dimension and weakened magnetism in close to the screen electrode side for attracting the positive ions generated from a positive electrode and weakening the lines of magnetic force in that part. CONSTITUTION:The xenon gas G which passed through a flow rate adjustor 3 is introduced into s neutralizer 6, and the electrons E for neutralization are emitted. The gas G which passed through a flow rate adjustor 4 is discharged as atoms A into an ion generating chamber 10 from a distributor 12 through an insulation device 7, and the gas G which passed through a flow rate adjustor 5 is allowed to emit atoms A, positive ions I and electrons E from a main cathode 9. The atoms A are ionized to generate positive ions I in the ion generating chamber 10, and the positive ions I are attracted by a screen electrode 15, and acceleration-transported by an accelerating electrode 16, and a propulsion force is generated. In this case, a magnet 14F which is closest to the screen electrode 15 among the magnets 14 arranged in the ion generating chamber 10 is used, with the reduced dimension and weakened magnetism in comparison with other magnets.

公开(公告)号：JPH1010300A

公开(公告)日：1998-01-16

申请号：JP17867596

申请日：1996-06-20

Applicant: NAT AEROSPACE LAB

Inventor： HAYAKAWA YUKIO ,  KITAMURA MASAHARU

IPC: G21K1/00 ,  F03H1/00 ,  G21K5/04 ,  H01J27/02 ,  H01J37/08

Abstract: PROBLEM TO BE SOLVED: To prolong life and maintenance-free operation hour by making the shape of electrode hole ion screen electrodes non circuit and improving the circularity of the cross sectional shape of a charged particle beamlet. SOLUTION: A screen electrode 2 is fixed in a plasma generating chamber 1 and an acceleration electrode 3 is fixed by putting a spacer 5 in between. At this moment, the shift of electrode holes 6 and 7 in pairing electrodes 2 and 3, respectively, is not made excessive. The shape of the electrode holes 6(7) is chamfered hexagon and each electrode hole is arranged so that the apex (side) positions closest to adjacent electrode holed 6(7). Thus, the diameter of each electrode becomes maximum(minimum) at the closest point and minimum(maximum) at the mid point. In this manner, by making the electrode holes 36 and 7 be chamfered hexagon and making the apex or side be the closet point to adjacent electrode holes, the degree of circle of the charged particle beamlet is raised. As the results, the degree of wear on accelerating and decelerating electrodes on charged particle beamlet path due to impingement of the charged particles reduces.

公开(公告)号：JPH06249131A

公开(公告)日：1994-09-06

申请号：JP3579193

申请日：1993-02-24

Applicant: NAT AEROSPACE LAB ,  TOSHIBA CORP

Inventor： KITAMURA MASAHARU ,  MIYAZAKI KATSUHIRO ,  HAYAKAWA YUKIO ,  TAKAMA SHINICHI ,  YOSHIDA HIDEKI

IPC: F03H1/00

Abstract: PURPOSE:To keep the temperature of a magnet below tolerance limits even if an ion engine operates for many hours by providing a charged particle prevention member which is kept at negative potential for a shield case between a discharge vessel and the shield case in the ion engine which is mounted in an artificial satellite. CONSTITUTION:A charged particle prevention net 20 in the shape of net is provided between a discharge vessel 3 and a shield case 1 and is concentric with the discharge vessel 3. The charged particle prevention net 20 is kept at negative potential for the shield case 1. In this constitution, the particles which exist around an ion engine and are charged with minus charges receive resiliency from the charged particle prevention net 20 even if they try to advance to the discharge vessel 3 side and do not attach on an alumina flame coated layer 13. Consequently, the alumina flame coated layer 13 remains white even if the ion engine is operated for many hours. It is possible to keep visible ray absorption rate at a low rate and prevent the rise of temperature of a magnet 11 due to solar heat.

公开(公告)号：JPH05321821A

公开(公告)日：1993-12-07

申请号：JP12357892

申请日：1992-05-15

Applicant: NAT AEROSPACE LAB ,  TOSHIBA CORP

Inventor： KITAMURA MASAHARU ,  MIYAZAKI KATSUHIRO ,  HAYAKAWA YUKIO ,  YOSHIDA HIDEKI ,  HARA SATOSHI

IPC: F03H1/00

Abstract: PURPOSE:To provide an ion thruster capable of maintaining the interval between grids at all times. CONSTITUTION:A screen grid 13 and an acceleration grid 14 are respectively supported with a discharge container through electrode support mechanisms 20, 22. The mechanisms 20, 22 are composed of spring members 23, 42 of which one end is respectively fixed to the screen grid 13 and the acceleration grid 14 and of which the other end is respectively fixed to spring members 23, 41 extending in parallel with the axial line of the discharge container, and intermediate support mechanisms 24, 42 arranged between the other side of spring members 23, 41 and the discharge container.

公开(公告)号：JPH02130271A

公开(公告)日：1990-05-18

申请号：JP28103288

申请日：1988-11-07

Applicant: NAT AEROSPACE LAB

Inventor： HAYAKAWA YUKIO ,  MIYAZAKI KATSUHIRO ,  KITAMURA MASAHARU

IPC: F03H1/00

Abstract: PURPOSE:To reduce the consumed electric power and the generated heat quantity by reducing the rate of leak of electrons into an ion extracting grid system by keeping the potential of a screen grid at the negative potential in comparison with a hollow cathode. CONSTITUTION:An ion extracting grid system 2A is constituted of an accelerating grid 21 and a screen grid 22. A bias electric power source circuit 8 is set at the negative potential in comparison with a hollow cathode 3 for the screen grid 22. The number of electrons which can not reach the screen grid 22 increases, and the flying distance of these electrons is extended, and chances of collision of these electrons with neutral atoms and of the electrolytic dissociation increase. Therefore, the number of electrons which the hollow cathode 3 must liberate for the generation of the ions in the equal quantity, in other words, the electric discharge current is reduced, and the electric power necessary for the electric discharge can be reduced at a low cost. Further, also the generated calorific heat can be reduced.

公开(公告)号：JPH05248346A

公开(公告)日：1993-09-24

申请号：JP4862292

申请日：1992-03-05

Applicant: NAT AEROSPACE LAB ,  TOSHIBA CORP

Inventor： HAYAKAWA YUKIO ,  YOSHIDA HIDEKI

IPC: F03H1/00

Abstract: PURPOSE:To embody high thrust and high efficiency by using a field formation means to form inside a discharge container an electric field for restricting the area into which electrons advance along the lines of magnetic force of a cusp field generated by a plurality of magnets provided within the discharge container. CONSTITUTION:Annular magnets 12a-12e are provided on the inner wall surface of a discharge container 1 with alternating N and S poles, and magnet covers 13a, 13b made of nonmagnetic metal are provided around the magnets 12b, 12d. The electric potential of the magnent covers 13a, 13b is kept at the same electric potential as a hollow cathode for use as a main cathode by a power supply 14, i.e., to the cathode potential. When electrons (e) released from the hollow cathode and entering the discharge container 1 flow into a cusp area as they cling to the lines M of magnetic force of the cusp field after being bombarded with an operating gas, they are decelerated by an electrostatic field generated by the magnet cover 13a and are reflected near the field and allowed to advance into adjacent cusp field; i.e., the area into which the electrons advance is restricted so as to narrow a plasma passage, thus decreasing the loss of plasma.

公开(公告)号：JPH01280687A

公开(公告)日：1989-11-10

申请号：JP11004188

申请日：1988-05-06

Applicant: NAT AEROSPACE LAB ,  MITSUBISHI ELECTRIC CORP

Inventor： HAYAKAWA YUKIO ,  TAKEGAHARA HARUTAKA

IPC: F03H1/00

Abstract: PURPOSE:To prevent thermal demagnetization of a permanent magnet in an ion generating chamber and to enable execution of high performance operation for a long time, by a method wherein white coating, e.g., alumina, zircon, cordierite, steatite, is applied on the outer wall of the ion generating chamber. CONSTITUTION:A white coating part 1b is formed to a pure iron part 1a of an ion generating chamber 1. When, as noted above, white coating, e.g., alumina, zircon, cordierite, steatite, is applied on the outer wall of the ion generating chamber 1, heat emission to the outside is increased. Thus, an increase in temperature in the ion generating chamber due to discharge energy for the generation of ion can be suppressed, thermal demagnetization of a permanent magnet due to operation for a long time, capture of electron due to the thermal demagnetization, deterioration of confinement of plasma can be prevented from occurring. This constitution enables operation of an electron impact type cusp ion engine for a long time.

公开(公告)号：JP2003124741A

公开(公告)日：2003-04-25

申请号：JP2001320563

申请日：2001-10-18

Applicant: NAT AEROSPACE LAB ,  JAPAN SCIENCE & TECH CORP

Inventor： SAWARA HIRONORI ,  HAYAKAWA YUKIO ,  SHIMIZU MORIO

IPC: G02B5/10 ,  F24S23/71 ,  H01Q3/20 ,  H01Q19/185 ,  F24J2/12

Abstract: PROBLEM TO BE SOLVED: To change the convergence characteristics of electromagnetic waves corresponding to a purpose in an electromagnetic wave converging device to be used as a sunlight converging device or electromagnetic wave transmitter/ receiver for communication. SOLUTION: This device is composed of a linear focusing reflector, in which a cross-sectional form vertical to a bus is a parabolic line or curved line simulating this parabolic line and when varying the cross-sectional form varying a focal distance by varying the cross-sectional form, any one of or both a bend moment and an axial force are loaded on both the terminals or closely to both the terminals of a mirror board comprising the reflector. By locating such a linear focusing reflector so that the buses can be almost perpendicular to each other and focal positions can be matched, the point focusing type variable focal distance electromagnetic wave converging device can be obtained.

公开(公告)号：JP2002339859A

公开(公告)日：2002-11-27

申请号：JP2001147202

申请日：2001-05-17

Applicant: NAT AEROSPACE LAB

Inventor： HAYAKAWA YUKIO ,  SHIMIZU MORIO

IPC: G02B5/10 ,  F03H99/00 ,  F24S23/74 ,  F24S23/79 ,  G02B7/182 ,  G02B17/06 ,  H01Q15/16 ,  H01Q19/18 ,  F03H5/00

Abstract: PROBLEM TO BE SOLVED: To provide a solar collecting device which is light in weight and has a high solar light collecting performance. SOLUTION: The device includes a mirror group consisting of a primary reflecting mirror 11 and a secondary reflecting mirror 12 each having a shape of section of the same parabola in an arbitrary section perpendicular to a certain direction. A primary reflection of an incident ray is carried out with the primary reflection mirror, and then a secondary reflection of the incident ray is carried out with the secondary reflection mirror, thereby focusing a solar ray to one point. Since a parabolic reflector of lines focus type is adopted, the reflector is constituted of a frame of predetermined shape and a film mirror body, and the electromagnetic wave focusing device can be made thin and lightweight. Further, the electromagnetic wave focusing device can be bent without considerable loss of accuracy and considerable increase of mass. Accordingly, the mirror body of itself is bent, made small, stored in such a narrow space of a rocket or the like, transported to a space the solar collecting device which has high light collecting performance with accuracy is realized on the spot.

公开(公告)号：JP2000161201A

公开(公告)日：2000-06-13

申请号：JP33711398

申请日：1998-11-27

Applicant: NAT AEROSPACE LAB ,  TOSHIBA CORP

Inventor： KITAMURA MASAHARU ,  MIYAZAKI KATSUHIRO ,  HAYAKAWA YUKIO ,  YOSHIDA HIDEKI ,  AKAI KIMIKAZU ,  TAKAMA SHINICHI

IPC: F03H1/00

Abstract: PROBLEM TO BE SOLVED: To enlarge an ion engine by radiating a part of heat generated by a hollow cathode, and restraining quantity of heat moving to a discharge vessel from the hollow cathode. SOLUTION: Ionized plasma being a heat source of a hollow cathode 9 of a main cathode is formed in a range of several mm of the tip in a cathode insert 13. Most of heat generated from the ionized plasma is transmitted to a flange 14a via a support cylinder 17 and a cathode tube 15 from the cathode insert 13, and is transmitted to a lower end part of a heat shielding cylinder body 32 from the flange 14a. A high heat radiation rate surface part 34 is formed in a part up to a flange 33 from a lower end on the outer peripheral surface of the heat shielding cylinder body 32. Most of the heat transmitted to the heat shielding cylinder body 32 is radiated in the direction other than the direction of a discharge vessel 3 from the high heat radiation rate surface part 34, and is radiated in a space from a shield case to thereby restrain quantity of heat moving to the discharge vessel 3 from the hollow cathode 9.