| Class Number |
Class Name |
No. of Patents |
| 181/126 |
Anatomic or prosthetic relation |
23 |
| 181/127 |
Dentiphone |
5 |
| 181/128 |
Ear and mouth |
20 |
| 181/130 |
Auditory canal insert |
168 |
| 181/133 |
Deflector type |
7 |
| 181/135 |
Ear insert |
224 |
| 181/134 |
Eardrum |
10 |
| 181/131 |
Stethoscope |
193 |
| 181/132 |
With diaphragm |
17 |
| 181/136 |
Deflector type |
26 |
| 181/129 |
Ear |
194 |
| 181/137 |
Receiver |
76 |
| 181/30 |
Auditorium |
60 |
| 181/141 |
Combined |
142 |
| 181/148 |
Diaphragm and enclosure |
191 |
| 181/154 |
Inclined diaphragm |
58 |
| 181/149 |
Moisture proof |
40 |
| 181/150 |
Recessed (e.g., wall-mounted, etc.) |
216 |
| 181/155 |
Reflector baffle |
194 |
| 181/156 |
Reflex baffle |
283 |
| 181/153 |
Rounded enclosure (e.g., curved, etc.) |
165 |
| 181/152 |
With horn |
172 |
| 181/151 |
With sound-absorbing means |
140 |
| 181/157 |
Diaphragm |
59 |
| 181/167 |
Critically defined material or coating |
105 |
| 181/169 |
Fibrous material |
71 |
| 181/170 |
Laminated type |
81 |
| 181/168 |
Metallic material |
32 |
| 181/158 |
Microphone type |
55 |
| 181/171 |
Mounting or suspension means |
201 |
| 181/172 |
Elastic suspension means |
128 |
| 181/173 |
Particular shape |
104 |
| 181/174 |
Variable thickness |
29 |
| 181/163 |
Plural dependent diaphragms |
73 |
| 181/164 |
Sectional diaphragm |
31 |
| 181/165 |
Concentric annular section |
24 |
| 181/166 |
With damping means |
84 |
| 181/161 |
With direct mechanical connection to drive unit |
34 |
| 181/162 |
Stylus bar |
1 |
| 181/159 |
With horn |
86 |
| 181/160 |
With resonant chamber |
92 |
| 181/123 |
Echo system |
9 |
| 181/124 |
Altitude or depth detection |
40 |
| 181/101 |
Geophysical or subsurface exploration |
36 |
| 181/107 |
Programmed or timer-controlled |
36 |
| 181/108 |
Seismic source and detector |
96 |
| 181/109 |
Aerial |
4 |
| 181/112 |
Plural detectors |
120 |
| 181/111 |
Plural sources |
71 |
| 181/110 |
Underwater |
142 |
| 181/122 |
Seismic wave detection |
139 |
| 181/113 |
Seismic wave generation |
150 |
| 181/115 |
Bubble suppression or control |
49 |
| 181/116 |
Explosive |
69 |
| 181/117 |
Gas |
40 |
| 181/118 |
Underwater |
87 |
| 181/119 |
Fluid means |
119 |
| 181/120 |
Underwater |
221 |
| 181/121 |
Moving weight |
169 |
| 181/114 |
Vehicle-mounted |
135 |
| 181/102 |
Well logging |
230 |
| 181/105 |
Bore hole or casing condition |
159 |
| 181/104 |
Directional source or detector |
98 |
| 181/103 |
Programmed or timer-controlled |
40 |
| 181/106 |
Seismic wave generation |
235 |
| 181/404 |
Hobby craft engine muffler |
4 |
| 181/138 |
Mechanical telephone |
6 |
| 181/.5 |
Miscellaneous |
96 |
| 181/143 |
Moving sound producer or deflector |
12 |
| 181/144 |
Plural diaphragm sound sources |
231 |
| 181/145 |
Plural chambers |
139 |
| 181/147 |
Three diaphragms |
82 |
| 181/146 |
With sound-asborbing means |
70 |
| 181/403 |
Refrigerator compresssor muffler |
169 |
| 181/125 |
Sound location |
8 |
| 181/175 |
Sound-modifying means |
135 |
| 181/206 |
By wave interference |
120 |
| 181/211 |
Combined |
62 |
| 181/198 |
Housing or enclosure (e.g., sound confining and absorbing) |
116 |
| 181/200 |
Machine type enclosure |
105 |
| 181/202 |
Electical type devices (e.g., transformers, motors, etc.) |
107 |
| 181/204 |
Internal-combustion engine |
204 |
| 181/201 |
Offfice type devices (e.g., typewriters, teleprinters, etc.) |
22 |
| 181/205 |
Partial enclosure or shroud |
50 |
| 181/203 |
Reaction engine test chamber |
9 |
| 181/199 |
Speaker type |
505 |
| 181/177 |
Intensifying horn |
39 |
| 181/178 |
Collapsible |
13 |
| 181/184 |
Having apertures in walls |
27 |
| 181/180 |
Material |
12 |
| 181/189 |
Multisection housing |
22 |
| 181/190 |
Separable |
16 |
| 181/192 |
Particular shape of the horn |
60 |
| 181/194 |
Doubly folded sound path |
17 |
| 181/193 |
Spiral sound path |
7 |
| 181/195 |
Wide angle annular outlet |
18 |
| 181/187 |
Plural intensifying portions |
43 |
| 181/188 |
Similar portions |
20 |
| 181/191 |
With external sound deflector |
33 |
| 181/179 |
With particular mounting structure |
28 |
| 181/182 |
With resonant chamber |
36 |
| 181/183 |
Double wall |
3 |
| 181/185 |
With sound-path restriction |
36 |
| 181/186 |
Adjustable |
9 |
| 181/181 |
With vibratory filaments |
2 |
| 181/176 |
Lens |
45 |
| 181/207 |
Mechanical vibration attenuator |
191 |
| 181/208 |
Damping of flexural structure |
132 |
| 181/209 |
Relatively moving parts |
48 |
| 181/296 |
Methods |
130 |
| 181/212 |
Muffler, fluid conducting type |
74 |
| 181/241 |
Adjustable muffler (i.e., internal or external parts) |
69 |
| 181/229 |
Carburetor, burner, or compressor intake silencer |
229 |
| 181/244 |
Corrosion prevention |
20 |
| 181/245 |
Internally coated parts |
8 |
| 181/246 |
Nonmetallic |
18 |
| 181/233 |
Liquid motion silencer |
51 |
| 181/234 |
Water-closet type |
13 |
| 181/240 |
Manifold type |
114 |
| 181/242 |
Mouthpiece (e.g., telephone, microphone, etc.) |
28 |
| 181/238 |
Multiple distinct inlets and/or outlets |
77 |
| 181/239 |
Outlets |
77 |
| 181/227 |
Pipe-muffler (e.g., tail pipe type) |
138 |
| 181/230 |
Pneumatic type motor (e.g., air hammer, etc.) |
165 |
| 181/213 |
Reaction engine type |
150 |
| 181/218 |
Ground installation silencer |
24 |
| 181/217 |
Removable silencer unit (e.g., mobile) |
21 |
| 181/214 |
Upstream (e.g., intake silencer) |
80 |
| 181/219 |
With adjustable internal baffles |
21 |
| 181/215 |
With adjustable outlet nozzle |
29 |
| 181/216 |
Longitudinally adjustable section |
13 |
| 181/220 |
With disparate fluid mingling |
94 |
| 181/221 |
Liquid |
17 |
| 181/222 |
With sound absorbing material |
95 |
| 181/232 |
Separate distinct units serially connected |
51 |
| 181/223 |
Silencer for firearms |
44 |
| 181/224 |
Sound absorbing ventilating duct or curb (e.g., a/c, heat, air flow type) |
224 |
| 181/247 |
Straight-through passage |
40 |
| 181/248 |
Continuous conduit |
42 |
| 181/249 |
With expansion chamber |
113 |
| 181/251 |
And multi-passage |
48 |
| 181/250 |
And side branch |
114 |
| 181/255 |
Expansion chamber |
165 |
| 181/253 |
With muffler bypass |
33 |
| 181/254 |
Valve controlled |
83 |
| 181/252 |
With sound absorbing material |
224 |
| 181/235 |
Underwater discharge |
38 |
| 181/226 |
With adjustable fluid flow |
25 |
| 181/264 |
With baffle or baffle structure |
169 |
| 181/282 |
Casings |
223 |
| 181/283 |
Air or liquid cooled |
27 |
| 181/267 |
Coaxial foraminous walls |
36 |
| 181/269 |
Expansion chamber type |
134 |
| 181/275 |
And multi-passage |
87 |
| 181/273 |
And side branch chamber |
86 |
| 181/272 |
Plural chambers |
374 |
| 181/271 |
With adjustable or flexible wall |
26 |
| 181/270 |
With alternating partial baffles along the length of casing |
43 |
| 181/274 |
With centrifugal flow |
19 |
| 181/277 |
Movable baffle |
42 |
| 181/278 |
Biased |
25 |
| 181/268 |
Multi-passage |
149 |
| 181/281 |
Perpendicular and/or oblique |
62 |
| 181/265 |
Retroverted |
144 |
| 181/266 |
And side branch chamber |
60 |
| 181/276 |
Side branch |
75 |
| 181/279 |
Spiral |
52 |
| 181/280 |
Helical |
47 |
| 181/259 |
With disparate fluid mingling |
21 |
| 181/262 |
Induced by suction |
49 |
| 181/263 |
Motion induced |
19 |
| 181/260 |
Liquid |
25 |
| 181/261 |
Sprayed |
11 |
| 181/228 |
With exhaust pipe |
140 |
| 181/225 |
With fan to assist fluid flow |
92 |
| 181/236 |
With muffler cut-out |
19 |
| 181/237 |
With pressure relief safety valve |
58 |
| 181/243 |
With repair, replacement, or quick disassembly |
130 |
| 181/231 |
With solid particle separator (e.g., spark arrestor, vacuum cleaner, etc.) |
107 |
| 181/256 |
With sound absorbing material |
202 |
| 181/257 |
And multi-passage |
59 |
| 181/258 |
Pervious material interposed in flow path |
160 |
| 181/210 |
Sound absorbing fence or screen (e.g., jet engine or vehicle noise) |
153 |
| 181/284 |
Sound absorbing panels |
191 |
| 181/288 |
Cellular |
148 |
| 181/289 |
Light permeable |
27 |
| 181/285 |
Load bearing block type structure |
50 |
| 181/294 |
Materials |
303 |
| 181/287 |
Movable/foldable panels |
75 |
| 181/290 |
Multilayer panel or wall structure |
445 |
| 181/291 |
With membrane outer layer |
103 |
| 181/292 |
With perforated or porous face and honeycomb-like core |
220 |
| 181/286 |
Specific acoustical properties or dimensions |
337 |
| 181/293 |
With channels or cavities in surface layer |
147 |
| 181/295 |
Space absorbers |
121 |
| 181/196 |
Within tubular means |
39 |
| 181/197 |
Adjustable |
8 |
| | Speaking tubes | |
| 181/19 |
Alarms and indicators |
5 |
| 181/20 |
Combined mouth and ear pieces |
12 |
| 181/21 |
Mouthpieces |
16 |
| 181/18 |
Systems |
12 |
| 181/22 |
Tubes |
15 |
| 181/400 |
Wave coupling |
19 |
| 181/401 |
Earth |
159 |
| 181/402 |
Liquid |
47 |
| 181/139 |
Wave generation and detection |
25 |
| 181/142 |
Wave generation |
50 |
| 181/140 |
With vessel |
16 |
