Resources Contact Us Home
Browse by Category: Main > Communications
Class Information
Number: 181/247.gtoreq.251
Name: Acoustics >

Sub-classes under this class:

Class Number Class Name Patents
181/ Speaking tubes 0
181/.5 Miscellaneous 98
181/101 Geophysical or subsurface exploration 51
181/123 Echo system 10
181/125 Sound location 17
181/126 Anatomic or prosthetic relation 27
181/138 Mechanical telephone 6
181/139 Wave generation and detection 30
181/140 With vessel 16
181/141 Combined 150
181/142 Wave generation 62
181/143 Moving sound producer or deflector 13
181/144 Plural diaphragm sound sources 254
181/148 Diaphragm and enclosure 256
181/157 Diaphragm 75
181/175 Sound-modifying means 160
181/30 Auditorium 74
181/400 Wave coupling 19
181/403 Refrigerator compresssor muffler 195
181/404 Hobby craft engine muffler 5

Patents under this class:

Patent Number Title Of Patent Date Issued

  Recently Added Patents
Apparatus and method for noise removal by spectral smoothing
Plastic floor-wall transition methods, materials, and apparatus
Method for distributing advertisements to client devices using an obscured ad monitoring function
Solid-state imaging device and imaging apparatus
Bad column management with bit information in non-volatile memory systems
Disk-based storage device having read channel memory that is selectively accessible to disk controller
Semiconductor device and method of manufacturing the same
  Randomly Featured Patents
Nickel extraction process
Ski having compound curve undersurface
Removing solids from process separator vessels
Method and apparatus for efficient communication of management data in a telecommunications network
Ordered liquid crystalline cleansing composition with particulate optical modifiers
Eyeglass frames
Method of first interleaving of a two interleaver transmitter
III-nitride semiconductor light emitting device having a multilayered pad
Method for configuring a station connected to a field bus
Hardening of copper to improve copper CMP performance