B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
B65D43/00—Lids or covers for rigid or semi-rigid containers
B65D43/26—Mechanisms for opening or closing, e.g. pedal-operated
H—ELECTRICITY
H04—ELECTRIC COMMUNICATION TECHNIQUE
H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS
H04R1/00—Details of transducers, loudspeakers or microphones
H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
H04R1/34—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means
H04R1/345—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means for loudspeakers
Landscapes
Engineering & Computer Science
(AREA)
Health & Medical Sciences
(AREA)
Otolaryngology
(AREA)
Mechanical Engineering
(AREA)
Physics & Mathematics
(AREA)
Acoustics & Sound
(AREA)
Signal Processing
(AREA)
Soundproofing, Sound Blocking, And Sound Damping
(AREA)