baber/WOPTO huggingface dataset:
Patent EP-0893294-A3 (EP)
Inventor: HASHIMOTO HIDEHARU
IPC: B60K15/04
Filed: 1998-07-22
Abstract: A sealing member is provided at an inner periphery
sealing portion thereof with an inner tube portion arranged
to be moved toward a fuel feed port inner side with the
insertion of a fuel feed nozzle and to be moved toward a
fuel feed port opening side with the removal of the fuel
feed nozzle. The inner tube portion is provided, at the outer
periphery of the end thereof at the fuel feed port opening
side, with a tapered tube portion extending toward an outer
tube portion side. With the movement of the inner tube
portion toward the fuel feed port opening side, the inner
tube portion is increased in inner diameter such that the
increased inner diameter is greater than the outer diameter
of the fuel feed nozzle, and with the movement of the inner
tube portion toward the fuel feed port inner side, the inner
tube portion is reduced in inner diameter, causing the same
to stick fast to the outer periphery of the fuel feed nozzle.
Patent EP-0908700-A3 (EP)
Title: Navigationsgerät eines Kraftfahrzeugs
Inventor: WANNKE DIETMAR
IPC: G01C21/26
Filed: 1998-10-02
Abstract: Ein Navigationsgerät eines Kraftfahrzeugs, das zur Verbindung
mit einer Positionsbesimmungseinrichtung und einer Weglängensensoreinrichtung
vorgesehen ist und einen Massenspeicher (5)
für Straßennetze, eine Eingabeeinrichtung (7) für Fahrtziele
und eine Ausgabeeinrichtung (8) für Fahrthinweise zur Erreichung
eines Fahrtziels aufweist, erhält einen Zweitnutzen
durch eine elektronische Erstellung eines Fahrtenbuchs dadurch,
daß es zur Erstellung eines Fahrtenbuchs zur Eingabe
einer Fahrtart und Abspeicherung sowie Ausgabe wenigstens von
Fahrtziel, Fahrtart, Fahrtdatum und am Fahrtziel zurückgelegte
Weglänge eingerichtet ist.
Patent EP-0922543-A3 (EP)
Title: Längsschneide- und Rill-Maschine für Wellpappebahnen
Inventor: SCHNEIDER STEPHAN
IPC: B26D1/24
Filed: 1998-11-21
Abstract: Eine Längsschneide- und Rill-Maschine für Wellpappebahnen weist eine
Rill-Station (A), eine Längsschneide- und Rill-Station (B) und eine Längsschneide-Station
(C) auf, die in Transportrichtung (3) einer Wellpappebahn
(4) hintereinander angeordnet sind. Die Längsschneide- und Rill-Station
(B) weist einerseits paarweise ein Rillwerkzeug (23) und ein mit
diesem zusammenwirkendes Gegen-Rillwerkzeug (24) und andererseits
jeweils paarweise ein Messer (25) und ein Gegenwerkzeug (26) auf.
Patent EP-0860394-A3 (EP)
Title: Aufhängung einer Schiene, insbesondere einer nach unten offenen hohlprofilförmigen Schiene
Inventor: BECKER KLAUS DR-ING
IPC: B66C7/08
Filed: 1998-02-17
Abstract: Die Erfindung betrifft eine Vorrichtung zum Aufhängen einer Schiene, insbesondere einer
nach unten offenen hohlprofilförmigen Schiene, an einem Tragwerk über ein an dem
Tragwerk und an der Schiene befestigtes Zugelement. 
     Erfindungsgemäß ist vorgesehen, daß mindestens ein vom Zugelement (4) auf Vorspannung
gehaltenes Zusatzelement (9) zur Übertragung von Druckkräften zwischen der Schiene (1)
und dem Tragwerk (6) vorgesehen ist.
Patent EP-0854351-A3 (EP)
Inventor: KASORI NAOTO
IPC: G01C5/00
Filed: 1998-01-21
Abstract: A laser survey instrument which comprises a rotary
irradiation system main unit (1) and an object reflector
(80) . The object reflector (80) has two or more
reflection sectors, at least one of which has a reflection
surface (84b,85b) with a gradually changing shape. The
rotary irradiation system main unit (1) comprises a light
emitter (3) for emitting a polarized irradiation light
beam, a rotator (2) for rotating and irradiating the
polarized irradiation light beam toward the object
reflector (80) and for detecting an irradiating direction,
a tilt setting unit for tilting a rotary irradiation plane
of the polarized irradiation light beam, a detecting means
(4) for detecting a polarized reflection light beam
reflected from said object reflector and entering the
rotary irradiation system main unit via said rotator, a
reflection light detecting circuit for identifying the
object reflector from an output of the detecting means (4)
and a control unit (60) for tracing said object reflector
(80) by operating said tilt setting unit based on
detecting a condition of said reflection light detecting
circuit and for tilting the rotation plane of said
polarized irradiation light beam.
Patent EP-0860606-A3 (EP)
Inventor: ROESGREN CARL-ERIK
IPC: F02M59/46
Filed: 1998-02-20
Abstract: An arrangement for an injection pump in an internal
combustion engine, especially a large diesel engine, in
which the injection pump (2) is provided with a pressure
medium controlled feed control valve (11), the flow circuit
of which includes a pressure medium source (14), from which
pressure medium is pumped through a delivery duct (16a) into
a feed duct (17,18,20,21,22,22a), which is provided with a
non-return valve (23) and is connected to a pressure chamber
(13) influencing the control valve (11) and to a spill
passage (24) to be switched off by means of a solenoid valve
(25), whereby closing of the solenoid valve (25) is arranged
to provide a pressure increase in the pressure chamber (13)
and, thus, a change of the state of the control valve (11).
The feed duct (17,18,20,21,22,22a) between the delivery duct
(16a) and the control valve (11) is dimensioned to be
relatively thin and long and is arranged at least to its
main part to be a stationary part of the injection pump (2),
of its supporting construction (3) or of a stationary
construction unit to be attached to these. Hereby a compact
assembly can be provided.
Patent EP-0871307-A3 (EP)
Inventor: GOVINDARAJU RAMA K
IPC: G06F13/24
Filed: 1998-03-18
Abstract: An apparatus for a distributed system having a plurality of nodes
and a switch network for passing messages between nodes, each message
being sent from a source node to a target node. Each node is connected to
the switch network by an adapter having a count register for adding the
value of the packets in messages received by the adapter to the value in
the count register and a threshold register for containing a desired
threshold value. An interrupt generator generates interrupts when the
value in the count register is equal to or greater than the value in the
threshold register. The value in the threshold register may be changed
under program control to enable or disable interrupts.
Patent EP-0944008-A3 (EP)
Inventor: AOIKE HITOSHI
IPC: G06Q30/06
Filed: 1998-11-11
Abstract: A service providing system according to the present invention is adapted to
systematically providing a diversity of services for the user. The service providing
system includes a service providing apparatus (10; 210) and an input device (20, 21,
22, 23, 24, 25; 220). The service providing apparatus (10; 210) comprises a
computer unit (12) capable of executing a predetermined program each having its
program ID. Each of the services also has its service ID associated with at least one
of the programs. The user can input a service ID through the input device (20, 21,
22, 23, 24, 25; 220) to the service providing apparatus (10; 210) to specify a desired
service. The computer unit (12) has a CPU (34) and a memory (33). The memory
(33) has a predetermined relational table between the service ID and corresponding
program IDs which are appropriate to the service ID. The service providing
apparatus (10; 210) is operated to select at least one of program IDs from the
relational table on the basis of the inputted service ID to display a service information
table (D1 and D2) on its screen. The service providing apparatus (10; 210) thus
constructed allows the user to select a procedure for the desired service from the
service information table (D1 and D2), there by making it possible to execute the
appropriate programs to perform various functions according to the selected
procedure.
Patent EP-0894906-A3 (EP)
Inventor: RUTKOWSKI MICHAEL JOSEPH
IPC: E03F9/00
Filed: 1998-06-26
Abstract: The feed control device particularly suited for
mounting on a hand held, power driven drain cleaning
apparatus having an elongate rotatable snake (24) comprises
a tubular housing (12) having a transverse wall (20)
therein provided with a passage (22) for the snake (24), a
pair of driving rolls (28, 30) mounted on the wall (20) for
rotation about axes skewed relative to the housing axis
(14) and a drive actuating roll (50) mounted on the housing
(12) for radial displacement to engage the rotating snake
(24) against the driving rolls (28, 30) . The drive
actuating roll (50) provides the inner end of an actuating
drive unit (42) having an outer end engaged by a pivotal
lever (74) on the housing (12) for displacing the actuating
drive roll (50) against the snake (24). The actuating drive
unit (42) is adjustable in length between the inner and
outer ends thereof and is removably supported on the
housing (12) and the lever (74) and outer end of the drive
actuating unit (42) interengage to retain the parts of the
actuating drive unit (42) in an adjusted position and to
releasably hold the drive actuating unit (42) on the
housing (12).
Patent EP-0924480-A3 (EP)
Inventor: DAS SATHISH R
IPC: F25D21/02
Filed: 1998-12-04
Abstract: In a heat pump system designed for use with a relatively low pressure refrigerant,
provision is made , by use of a vapor pressure control system, to use a higher pressure
refrigerant without replacement of the indoor coil and the line set. The vapor pressure
is sensed during periods of heat pump operation, and when the pressure reaches a
predetermined maximum threshold level, the outdoor fan speed is reduced to thereby
cause the vapor pressure to be reduced. When the vapor pressure is reduced to a
predetermined minimum threshold level, then the fan speed is resumed so as thereby
allow the vapor pressure to again be increased.
Patent EP-0929041-A3 (EP)
Title: Verfahren und Anordnung zum Betreiben eines Bussystems
Inventor: ROHM PETER
IPC: G06F13/14
Filed: 1999-01-08
Abstract: Die Erfindung betrifft ein Verfahren und eine Anordnung zum
Betreiben eines Bussystems mit mindestens Mastereinheit und
mindestens Slaveeinheit, mit einem Bus und einer Bussteuereinheit
Steuerung der zur Busarbitrierung und zur Steuerung
der Datenübertragung. Die Datenübertragung aufgeteilt in einen
Anforderungsdatentransfer und in einen Antwortdatentransfer
und in der Zeit zwischen Anforderungsdatentransfer und
Antwortdatentransfer der Bus freigegeben ist für die Datenübertragungen
weiterer Mastereinheiten und Slaveeinheiten.
Beim Antworttransfer findet ein Wechsel zwischen Master und
Slave statt.
Patent EP-0934842-A3 (EP)
Title: Cabrioletverdeck für ein Kraftfahrzeug
Inventor: SCHEFFZUEK MATTHIAS
IPC: B60J7/04
Filed: 1999-01-15
Abstract: Ein Cabrioletverdeck für ein Kraftfahrzeug, ist mit
seitlichen Dachrahmen (4) und C-Säulen (3) versehen. Das Cabrioletverdeck
weist ein rollenartiges Verdeck (1) auf,
das mit einer Vielzahl von miteinander verbundenen
Einzellamellen (12) versehen ist. Das Verdeck ist in einen
Stauraum (5) im hinteren Bereich des Kraftfahrzeuges aufwickelbar.
Die Dachrahmen und die C-Säulen sind in den
hinteren Bereich des Kraftfahrzeuges absenkbar. Das
Verdeck ist bei abgesenktem Dachrahmen und C-Säulen in
seitlichen Führungsschienen (8) unterhalb einer Fensterkante (9)
des Kraftfahrzeuges in Fahrtrichtung nach vorne
zur wenigstens teilweisen Abdeckung des Fahrzeuges aus
dem Stauraum ausrollbar.
Patent EP-0961004-A3 (EP)
Title: Lüftungsvorrichtung zur Anordnung in einem Wandflächenbereich eines Gebäudes
Inventor: ARNTJEN GERD
IPC: F24F11/02
Filed: 1999-02-19
Abstract: Die Erfindung betrifft eine Lüftungsvorrichtung zur Anordnung in einem
wandflächenbereich eines Gebäudes. 
     Derartige Lüftungsvorrichtungen sind für sogenannte Kaltställe marktüblich.
Dabei ist eine Außenseite eines Stallgebäudes gegen Windeintritt nur mit
einem oder mehreren übereinander angeordneten planenartigen
Wandelementen verschlossen, die sich zur weitgehenderen Belüftung des
Stalles öffnen lassen, indem das Wandelement nach Art eines Rollos nach oben
aufgewickelt wird. 
     Der Erfindung liegt die Aufgabe zugrunde, eine Lüftungsvorrichtung
aufzuzeigen, bei der die Öffnung des Wandelementes durch definiertes bzw.
kontrolliertes Herablassen des oberen Randes des Wandelementes bei
gleichzeitigem Aufwickeln des Wandelementes und nur mittels eines einzigen
Antriebes erfolgt. 
     Diese Aufgabe wird erfindungsgemäß dadurch gelöst, daß das Wandelement (1)
und das Zugorgan (3,5,7,17) zusammen mit weiteren Elementen eine letztlich über das
einzige gemeinsame Antriebsorgan (10) mehr oder weniger geschlossene Schleife
bilden, wobei vorzugsweise auch das Zugorgan (3,5,7,17) selbst in dem Maße auf der
Wickelwelle (9) abgewickelt wird, in dem das Wandelement (1) aufgewickelt wird,
oder umgekehrt, und zwar zueinander gegensinnig.
Patent EP-0949755-A3 (EP)
Inventor: SEGAMI MASAHIRO
IPC: H03F3/00
Filed: 1999-03-23
Abstract: The switched capacitor amplifier comprises first hold capacitors,
second hold capacitors, a transconductance amplifier, a first switch
circuit for either allowing the first hold capacitors to retain an
input voltage, or for outputting the retained input voltage through
the transconductance amplifier, and a second switch circuit for
either feeding a voltage obtained by reversing the polarity of the
voltage retained by the second hold capacitors back to the
transconductance amplifier for output as the amplifier's output
voltage, or for allowing the voltage retained by the first hold
capacitors to be held by the second hold capacitors.
Patent EP-0960713-A3 (EP)
Inventor: GELLERT JOBST ULRICH
IPC: B29C45/27
Filed: 1999-05-04
Abstract: Injection molding apparatus having a number of heated nozzles extending in a row from an elongated heated melt distribution manifold. Each heated nozzle has a pair of mounting flanges extending outwardly in opposite directions adjacent its rear end. Hollow insulating and locating bushings extend forwardly from the mounting flanges to the cooled cavity plate. The combination of the mounting flanges and the insulating and locating bushings accurately locates the heated nozzles very closely together in a row and spaces the heated elongated melt distribution manifold rearwardly from the cooled cavity plate. <IMAGE>
Patent EP-0990570-A3 (EP)
Title: Anordnungen und Verfahren zur Vermeidung von Überschlägen bei Bremsvorgängen und Beschleunigungsvorgängen für Kraftfahrzeuge
Inventor: BLOSCH GEORG
IPC: B60T8/32
Filed: 1999-06-02
Abstract: Anordnung zur Vermeidung von Überschlägen bei
Beschleunigungsvorgängen für Kraftfahrzeuge, insbesondere
Ein- oder Zweispurfahrzeuge wie Motorräder oder PKWs, mit
Mitteln (101, 104) zum Vergleich einer Drehzahldifferenz
zwischen der Drehzahl wenigstens eines Vorderrades oder der
Vorderachse und der Drehzahl wenigstens eines Hinterrades
oder der Hinterachse des Kraftfahrzeugs mit einem
einstellbaren Drehzahldifferenz-Schwellwert, Mitteln (101,
104) zur Ermittlung einer Radbeschleunigung für wenigstens
ein Vorderrad und für wenigstens ein Hinterrad und Mitteln
(105) zur Ansteuerung des Fahrzeugantriebs bei Erreichen
oder Überschreiten des Drehzahldifferenz-Schwellwerts, wenn
gleichzeitig für wenigstens ein Vorderrad die
Radbeschleunigung negativ und für wenigstens ein Hinterrad
die Radbeschleunigung positiv ist.
Patent EP-0984153-A3 (EP)
Inventor: SAITO TOMOAKI
IPC: F02B37/00
Filed: 1999-08-31
Abstract: A turbocharged engine control system having exhaust gas recirculation control means (26)
which detects a value relating to an actual excess air ratio and feedback controls an exhaust gas
recirculation valve (5) so as to bring the actual excess air ratio into coincidence with a target
excess air ratio and turbine efficiency control means (28) which controls a turbocharger (8) to
change turbine efficiency of the turbocharger is comprised of detection means (12) for detecting
a value relating to a pressure difference between pressure before and after the exhaust gas
recirculation valve (5) and control means (26) for controlling the turbine efficiency control
means (28) to vary a change rate at which the turbine efficiency changes so as to become lower
as the pressure difference rises. With the turbocharged engine control system, the control is
properly performed to improve fuel economy and reduce particulate such as smoke and unburnt
fuel and NOx emissions in exhaust gases without causing overshooting and/or hunting.
Patent EP-0985643-A3 (EP)
Inventor: OSHIMA TAKAYUKI
IPC: G03F1/60
Filed: 1999-08-27
Abstract: An object of the present invention is to provide a simple method for producing a synthetic quartz glass having excellent homogeneity and high transmittance, which is useful as an optical material in producing steppers equipped with an ArF excimer laser as a radiation source. A method for producing a synthetic quartz glass for use in ArF excimer laser lithography, which comprises irradiating a highly homogeneous synthetic quartz glass containing less than 60 ppb of Na with an ultraviolet radiation having a maximum wavelength of 260 nm for not less than the duration expressed by the following equation 1:   <MATH> wherein X represents an Na concentration (ppb), Y represents the duration of irradiation (hours), and Z represents the illuminance of an ultraviolet radiation on an irradiated surface (mW/cm<2>).
Patent EP-0991084-A3 (EP)
Inventor: LAWSON GLENN
IPC: H01B7/08
Filed: 1999-09-28
Abstract: Disclosed is a method for surrounding electrical cable, such as coax cable
or twinax cable, with an elastomer to form a twist capsule cable. The cables are
placed in a fixture and stretched to a desired tautness using rubber bands at
opposite ends of each cable without allowing the cables to sag in the fixture. The
cables are clamped into yokes at opposite ends of the fixture. An elastomer, such
as silicone, is poured into the fixture and allowed to cure. The portion of the
cables within the fixture are embedded into the elastomer after the elastomer
cures. Additional length of twist capsule cable can be fabricated by performing a
similar process on adjoining sections of cable. The elastomer is then coated with
a polyxylylene or similar polymer such as Parylene™ to prevent the elastomer
from rubbing on itself when coiled and when uncoiling. Advantageously, any
number of cables can be embedded in the elastomer to form the twist capsule
cable. Also advantageously, the present invention provides excellent attenuation
at 1GHz. Some channels operate between 10 MHz and 80 MHz. The cables are
capable of carrying radio, Identify Friend and Foe (IFF), Ethernet and other
signals.
Patent EP-1013978-A3 (EP)
Title: Befestigungselement aus Kunststoff
Inventor: BRUMM MATTHIAS
IPC: F16L3/237
Filed: 1999-10-15
Abstract: Die Erfindung bezieht sich auf ein Befestigungselement aus Kunststoff, mit einem
mittleren Haltebereich 2, welche oberseitig einen unter Druckeinwirkung
einen Hauptkörper 1 zumindest teilweise durchdringenden Bolzen 5 aufweist und
mit ein- oder beidseitig des Haltebereichs 2 angeordneten Lagerbereichen 3, 4
zur Aufnahme von Rohren oder Kabeln. Der Hauptkörper 1, der Bolzen 5 und
jeweils eine äußere Schale 10, 20 bestehen aus einer harten Materialkomponente,
wohingegen ein Innenkern 15, ein in eine Trägeröffnung einsetzbarer Spreizzapfen
16 und jeweils eine innere Schale 10', 20' aus einer weichen Materialkomponente
hergestellt sind.
Patent EP-1000983-A3 (EP)
Inventor: SCHUMACHER CHRISTIAN
IPC: C09B67/22
Filed: 1999-11-04
Abstract: Dye mixture contains reactive 1-(2-arylamino-4-chloro-1,3,5-triazin-6-yl-amino)-7-vinylsulfonylpheny lazo-8-hydroxy naphthalene-3,6-disulfonic acid (precursor) dye(s) (I) and 1-(2-arylamino-4-chloro-1,3,5-triazin-6-yl-amino)-7-arylazo-8-hydroxy naphthalene-3,6-disulfonic acid dye(s) (II) in 70:30 to 30:70 molar ratio. Dye mixture contains reactive 1-(2-arylamino-4-chloro-1,3,5-triazin-6-yl-amino)-7-vinylsulfonylpheny lazo-8-hydroxy naphthalene-3,6-disulfonic acid (precursor) dye(s) (I) and 1-(2-arylamino-4-chloro-1,3,5-triazin-6-yl-amino)-7-arylazo-8-hydroxy naphthalene-3,6-disulfonic acid dye(s) (II) of the given formulae in 70:30 to 30:70 molar ratio: M = hydrogen (H), an alkali metal or the equivalent of an alkaline earth metal; R<1>, R<7> = H, 1-4 carbon (C) alkyl, 1-4 C alkoxy, sulfo or carboxy;   R<2>, R<8> = H, 1-4 C alkyl or 1-4 C alkoxy; RA, RB = H or sulfo; R = H or 1-4 C alkyl; Y<1>, Y<2> = vinyl or ethyl with a substituent eliminated by alkali in the  beta -position; G, D = a benzene residue; R<3>, R<5> = H, 1-4 C alkyl, 1-4 C alkoxy, halogen, sulfo or carboxy; and R<4>, R<6> = H, 1-4 C alkyl, 1-4 C alkoxy or sulfo; or G, D = a naphthalene residue; R<3>, R<5> = H, methyl, sulfo or carboxy; and R<4>, R<6> = H or sulfo.
Patent EP-1001607-A3 (EP)
Inventor: QUEIROZ RICARDO L DE
IPC: G06T9/00
Filed: 1999-11-11
Abstract: A method and apparatus for compressing digital image data to
improve the efficiency of serial data transmission is disclosed. More
specifically, the present invention accomplishes image transmission by
providing multiple image processing modules, and then selecting the module
that will process the entire in the most efficient manner, based upon the
content of the data contained in the image. Image content is analyzed using
hierarchical vector quantization.
Patent EP-1004563-A3 (EP)
Inventor: UEDA AKIO
IPC: C08K5/05
Filed: 1999-11-29
Abstract: Disclosed is a process producing alcohols, which
comprises subjecting a mixture comprising an aldehyde having
from 2 to 5 carbon atoms and a polycondensate of the aldehyde
at a weight ratio of from 95 : 5 to 5 : 95 to a mixing hydrogenation
reaction in the presence of a catalyst to produce alcohols
corresponding to the aldehydes at the same time.
Patent EP-1013373-A3 (EP)
Inventor: KURZ ARTUR
IPC: B23Q5/40
Filed: 1999-12-20
Abstract: The drive assembly for the movement of machine components, e.g. slides or grips etc. and especially at a machine tool, has at least one threaded spindle (40) powered by a drive motor (21). A nut (5) rides on the spindle, rotated by a second drive motor (9) to give the working unit (56), e.g. a grip of the tool exchange mechanism, an axial movement and rotation around the spindle axis through the two drive motors. The grip is keyed on a shaft (44) which is keyed with the spindle.
Patent EP-0961520-A3 (EP)
Inventor: BERNSTEIN GREG M
IPC: H04L12/56
Filed: 1999-04-29
Abstract: A method and apparatus for efficiently transporting DS-X traffic in packet
form over an ATM or other packet network. Specifically, virtual connection or slot
provisioning and/or cell concentration techniques are used to compact the
amount of DS-X traffic broadcast between communications system devices such
as the access mux and the communications switch and spare bandwidth. In
provisioning, a configured DS-X loading of an end node supporting DS-X traffic is
ascertained. In turn, a minimum number of virtual connections for bearing
packetized DS-X traffic are established, either at communications system
configuration or as needed. In concentration processing, a dynamic association
between the virtual connections and the DS-X traffic is established, typically on a
per frame basis. Only those digital channels entering the node within a given time
frame which actually bear DS-X traffic will be assigned a slot within packet.
Concentration may be augmented by provisioning to further reduce bandwidth
requirements. In other disclosed aspects, permanent virtual channels or PNNI
soft permanent virtual connections may be used for the virtual connections where
ATM is chosen as the transport protocol.
Patent EP-0971463-A3 (EP)
Inventor: FURUKAWA YUKIO
IPC: H01S5/10
Filed: 1999-07-09
Abstract: A ring cavity laser has a polyhedral structure
contoured by a plurality of planes, and includes a ring
cavity having reflective faces formed by the planes of the
polyhedral structure, and an active medium (21, 117, 421,
521). The ring cavity laser is constructed such that
there exists a three-dimensional light path among light
paths of the ring cavity through which light pumped in
the active medium (21, 117, 421, 521) travels when the
light starts at a point on one reflective face, is
reflected by each reflective face and returns to the
starting point.