| Class Number |
Class Name |
No. of Patents |
| 338/1 |
Coherer type |
3 |
| 338/221 |
Detachable plug-type resistor unit |
40 |
| 338/278 |
Edgewise coiled helical strip resistance element |
10 |
| 338/207 |
Element and base permanently folded or rolled |
1 |
| 338/204 |
Element in layers piled or stacked between terminals |
37 |
| 338/205 |
With intervening conducting layer |
12 |
| 338/206 |
Expanded metal type |
15 |
| 338/209 |
Extensible |
2 |
| 338/210 |
Flexible or folding |
40 |
| 338/213 |
Beaded |
8 |
| 338/214 |
Cable type |
133 |
| 338/211 |
Element coated on flexible base |
43 |
| 338/212 |
Tape or sheet |
92 |
| 338/223 |
Granular or powdered element |
26 |
| 338/225 |
Carbon particles |
33 |
| 338/224 |
Granular or powdered mixtures |
21 |
| 338/296 |
Helical or wound resistance element |
23 |
| 338/298 |
Compound helix or winding |
9 |
| 338/302 |
Element coiled on cylindrical or prismatic core |
46 |
| 338/303 |
In helical groove on core |
16 |
| 338/301 |
Element coiled on flat or ribbon base |
18 |
| 338/300 |
Element forms a coating |
11 |
| 338/304 |
Element on frame or support |
35 |
| 338/305 |
Element extends in or through openings or grooves in frame or support |
23 |
| 338/297 |
Flat spiral winding |
16 |
| 338/299 |
Plural supported helices or windings |
30 |
| 338/66 |
Ignition interference suppressor type |
32 |
| 338/216 |
In coaxial transmission line or wave guide |
31 |
| 338/220 |
In detachable electrical connector |
52 |
| 338/219 |
In or on lamp socket or base |
18 |
| 338/226 |
Incased, embedded, or housed |
44 |
| 338/228 |
Casing extends through plate |
6 |
| 338/262 |
Casing or housing formed as a coating |
19 |
| 338/263 |
Helical or wound element |
4 |
| 338/264 |
Element coiled on a core |
10 |
| 338/265 |
Terminal or leads at one end of core |
3 |
| 338/266 |
Terminal surrounds element and/or core |
2 |
| 338/256 |
Casing or housing formed in plural layers external to element |
13 |
| 338/257 |
One layer a coating |
8 |
| 338/275 |
Casing or housing formed on and hardened on resistor (e.g., molded) |
67 |
| 338/232 |
Casing or housing readily openable and/or separable from element |
17 |
| 338/233 |
Elongated casing or housing with plug, disc, or cap at end |
7 |
| 338/252 |
Element embedded or enclosed in groove or recess |
33 |
| 338/253 |
With filling hardened in situ |
9 |
| 338/243 |
Element in insulation with outer metallic sheath |
23 |
| 338/245 |
Entire insulation or sheath formed as a coating |
3 |
| 338/244 |
Insulation coated on conducting liner |
2 |
| 338/250 |
Insulation formed and hardened in situ (e.g., molded) |
6 |
| 338/247 |
Plural part sheath |
4 |
| 338/248 |
Insulation formed and hardened in situ (e.g., molded) |
7 |
| 338/249 |
Parts formed as flat sheets |
9 |
| 338/251 |
Sheath embraces or folds over insulation |
5 |
| 338/246 |
With insulation and sheath external and internal to element |
1 |
| 338/238 |
Element inpowdered insulation with outer metallic sheath |
57 |
| 338/239 |
Plural elements or resistors |
18 |
| 338/242 |
Shape of sheath |
15 |
| 338/240 |
Terminals or leads adjacent |
20 |
| 338/241 |
Sheath only outside looped element |
13 |
| 338/254 |
Flattened resistance element between flat layers |
51 |
| 338/255 |
Layers coalesced or fused together |
12 |
| 338/267 |
Helical or wound element |
10 |
| 338/269 |
Casing or housing formed on and hardened on resistor (e.g., molded) |
18 |
| 338/270 |
Element coiled on a core |
28 |
| 338/268 |
Preformed sleeve engaging over element |
18 |
| 338/231 |
In liquid |
6 |
| 338/230 |
Metal casing or housing cast around element |
8 |
| 338/260 |
Plural resistors |
66 |
| 338/261 |
Helical or wound element |
7 |
| 338/229 |
Probe type |
42 |
| 338/258 |
Resistance element formed as a coating on interior of casing or housing |
7 |
| 338/271 |
Terminal forms casing or housing |
21 |
| 338/273 |
Terminal or lead extends into end of elongated casing or housing |
38 |
| 338/274 |
With sealing plug, disc or cap |
44 |
| 338/276 |
Terminal or lead extends through casing or housing wall |
44 |
| 338/272 |
Terminal or lead surrounds and secured to casing or housing |
18 |
| 338/234 |
With gaseous or vacuum spacing between element and casing or housing |
33 |
| 338/235 |
Plural elements or resistors |
18 |
| 338/236 |
Spacing of uniform thickness over length of element |
12 |
| 338/237 |
Hermetically sealed |
35 |
| 338/227 |
With resistance value indicator |
5 |
| 338/259 |
Wound, braided, or woven casing or housing |
6 |
| 338/68 |
Mechanically variable (e.g., rheostat) |
21 |
| 338/87 |
Contact adjustably inserted into resistance element (e.g., penetrating type) |
1 |
| 338/88 |
Powdered element |
1 |
| 338/114 |
Deformable |
171 |
| 338/115 |
Element in piled or stacked layers |
7 |
| 338/70 |
In or on lamp socket |
8 |
| 338/71 |
Resistor surfaces pressed together (e.g., compressible type) |
4 |
| 338/73 |
Resistor with contact angularly slidable on element |
6 |
| 338/74 |
Resistor with contact rectilinearly slidable on element |
5 |
| 338/72 |
Resistor with intervening connector between contact and element (e.g., taps) |
4 |
| 338/76 |
Interchangeable resistors of different resistance value |
1 |
| 338/80 |
Liquid resistance element |
41 |
| 338/82 |
Adjustable insulating barrier between electrodes |
10 |
| 338/81 |
Electrode separable from liquid element for switching |
6 |
| 338/86 |
Level of liquid element adjustable on electrodes (e.g., electrodes move up and down in element) |
15 |
| 338/83 |
Variable electrode separation |
8 |
| 338/85 |
Electrode rotatable |
2 |
| 338/84 |
Plural ganged electrodes |
4 |
| 338/89 |
Mathematical function (e.g., sine-cosine potentiometer) |
20 |
| 338/91 |
With mechanical converter |
2 |
| 338/90 |
With slab or card-type resistance element |
7 |
| 338/118 |
Movable contact electrically adjustable over length of resistance element |
47 |
| 338/120 |
Additional resistor adjustably shunts part of resistance element (e.g., varifunction type |
6 |
| 338/122 |
Coarse and fine resistance elements |
5 |
| 338/123 |
Plural elements and plural contacts |
14 |
| 338/124 |
Contacts interlinked (e.g., lost motion type) |
1 |
| 338/136 |
Contact clamped on resistance element |
3 |
| 338/143 |
Contact moves along turns of helical resistance element |
7 |
| 338/144 |
Contact lifts element from core |
0 |
| 338/145 |
Helical resistance element moves |
1 |
| 338/147 |
Resistor formed as a flat spiral |
2 |
| 338/149 |
With contact stop |
5 |
| 338/146 |
With helical collector parallel to helical element |
0 |
| 338/148 |
With helical screw for moving the contact |
2 |
| 338/153 |
Contact operated by pedal or treadle |
59 |
| 338/155 |
Contact rocks along element or taps |
4 |
| 338/157 |
Contact rolls along element or taps |
10 |
| 338/158 |
Contact rolls rectilinearly |
5 |
| 338/160 |
Contact slides along in contact with element |
107 |
| 338/162 |
Contact angularly slidable |
220 |
| 338/169 |
Contact pressure adjustable |
2 |
| 338/164 |
Hermetically sealed housing |
53 |
| 338/167 |
Spring-loaded contact |
40 |
| 338/174 |
With collector ring |
99 |
| 338/175 |
Ring, a shaft-bearing |
10 |
| 338/170 |
With contact biasing spring on contact arm or carrier |
22 |
| 338/165 |
With elongated rectilinear resistance element |
7 |
| 338/168 |
With flexible lead-in to contact |
7 |
| 338/163 |
With knob forming casing or covering |
57 |
| 338/171 |
With plural contact portions |
60 |
| 338/166 |
With removable actuating shaft or key |
24 |
| 338/172 |
With switching |
69 |
| 338/173 |
Contact separable from resistance element |
11 |
| 338/176 |
Contact rectilinearly slidable |
122 |
| 338/178 |
Contact separable from element for switching |
15 |
| 338/177 |
Contact surrounds resistor |
4 |
| 338/180 |
Screw-operated |
31 |
| 338/181 |
Screw, a fine-adjustment |
1 |
| 338/183 |
With collector bar |
27 |
| 338/182 |
With contact lock |
7 |
| 338/179 |
With series switch |
18 |
| 338/161 |
With element casing open over contact track |
14 |
| 338/138 |
Element tapered |
13 |
| 338/142 |
Element forms a coating |
11 |
| 338/141 |
Helical or wound |
4 |
| 338/139 |
Portion of element shorted |
5 |
| 338/140 |
With intervening connector between contact and element (e.g., taps) |
4 |
| 338/137 |
Plural contacts adjustable over single resistance element |
14 |
| 338/128 |
Plural |
142 |
| 338/130 |
Ganged |
14 |
| 338/133 |
Rectilinearly operated |
4 |
| 338/132 |
Resistors in tandem along rotary shaft or coupling |
19 |
| 338/131 |
Resistors individually adjustable |
16 |
| 338/134 |
Individually operated concentric shaft type |
17 |
| 338/129 |
Sequentially operated |
7 |
| 338/150 |
Resistance element moves |
17 |
| 338/152 |
With knob mounting or enclosing the element |
12 |
| 338/151 |
With liquid contact |
2 |
| 338/125 |
Unitary movable contact electrically bridges plural resistance elements |
15 |
| 338/127 |
Contact rotates between circularly arranged elements or taps |
10 |
| 338/126 |
Elements or taps in parallel |
10 |
| 338/154 |
With a flexible conductive strip separating the movable contact and the resistance element or taps |
8 |
| 338/119 |
With contact position indicating lamp |
17 |
| 338/159 |
With heat conducting or distributing path |
9 |
| 338/184 |
With housing |
118 |
| 338/185 |
With intervening connector between contact and element (e.g., taps) |
28 |
| 338/190 |
Angularly movable contact |
28 |
| 338/192 |
Resistance element enclosed |
2 |
| 338/193 |
Enclosure formed on and hardened on element |
4 |
| 338/191 |
With switch |
14 |
| 338/186 |
Connector formed as severed helical turns or as comb teeth |
0 |
| 338/194 |
Rectilinearly movable contact |
12 |
| 338/187 |
With arc suppressor |
3 |
| 338/188 |
With collector bar or ring |
13 |
| 338/189 |
With magnetic holder for controller arm |
2 |
| 338/156 |
With liquid contact |
2 |
| 338/121 |
With nonlinearity correction |
1 |
| 338/135 |
With zero setting or phasing |
9 |
| 338/69 |
Musical instrument playing key actuated |
28 |
| 338/77 |
Plug boxes |
2 |
| 338/92 |
Resistance element adjustably short-circuited |
34 |
| 338/93 |
Compressible spring type |
3 |
| 338/94 |
Liquid contact |
12 |
| 338/96 |
Spring contact strip progressively pressed along element |
11 |
| 338/97 |
Unitary movable contact electrically bridges resistance portions |
6 |
| 338/95 |
With intervening structure between element and short-circuiting means (e.g., taps) |
9 |
| 338/195 |
Resistance value varied by removing or adding material |
264 |
| 338/117 |
Slidable coextensive helical and linear contacts |
4 |
| 338/99 |
Surfaces pressed together (e.g., compressible type) |
144 |
| 338/100 |
Granular |
13 |
| 338/101 |
Pile type |
19 |
| 338/112 |
Contact surface area of piles variable |
7 |
| 338/108 |
Pedal- or treadle-operated |
20 |
| 338/102 |
With contactor moving along pile |
0 |
| 338/107 |
With electromagnetic holder |
1 |
| 338/103 |
With electromagnetic operator (e.g., electric motor) |
4 |
| 338/104 |
Force applied at both ends of pile |
4 |
| 338/105 |
With diaphragm-type biasing spring |
0 |
| 338/106 |
With initial pressure adjustment |
1 |
| 338/109 |
With initial pressure adjustment |
1 |
| 338/111 |
With intervening conducting structure |
4 |
| 338/113 |
With resilient pressure-applying linkage |
12 |
| 338/110 |
With switch actuated by resistor actuator |
4 |
| 338/78 |
With current reversing (e.g., reversing rheostat) |
3 |
| 338/116 |
With electromagnetic operator (e.g., electric motor) |
10 |
| 338/79 |
With element winding and/or unwinding |
2 |
| 338/199 |
With housing |
72 |
| 338/98 |
With motion or vibration damping means (e.g., dashpots) |
5 |
| 338/196 |
With resistor actuator position indicator |
48 |
| 338/75 |
With resistor cleaner |
5 |
| 338/197 |
With support |
30 |
| 338/198 |
With switch actuated by resistor actuator |
69 |
| 338/200 |
With switch |
73 |
| 338/201 |
Switch connects plural elements in parallel |
12 |
| 338/208 |
Mesh, woven, or braided resistance element |
43 |
| 338/334 |
Miscellaneous |
67 |
| 338/50 |
Mounted on wheels or vehicle |
30 |
| 338/202 |
Movable contact structure |
101 |
| 338/12 |
Movable magnet actuates resistor through housing or partition |
15 |
| 338/333 |
Particular configuration and/or dimension |
87 |
| 338/295 |
Plural resistance elements connected by a jumper or spacer |
89 |
| 338/48 |
Plural separate diverse resistors |
27 |
| 338/203 |
Readily severable into independent resistors |
43 |
| 338/11 |
Reflector directs heat on element |
0 |
| 338/321 |
Resistance element cores and frames |
17 |
| 338/13 |
Resistance value responsive to a condition |
84 |
| 338/25 |
Ambient temperature |
291 |
| 338/26 |
Cable or tape type (e.g., fire-detecting cable) |
33 |
| 338/27 |
Liquid contact or element |
8 |
| 338/31 |
Mechanically adjustable or variable |
2 |
| 338/28 |
Probe type |
218 |
| 338/29 |
Mechanically adjustable or variable |
5 |
| 338/30 |
Terminal forms casing or housing |
19 |
| 338/20 |
Current and/or voltage (e.g., ballast resistor) |
261 |
| 338/24 |
Indirectly heated |
32 |
| 338/22R |
Thermistor type |
974 |
| 338/23 |
Indirectly heated |
70 |
| 338/22SD |
Semiconductor |
279 |
| 338/21 |
Voltage surge-responsive or lightning arrester type |
363 |
| 338/33 |
Float actuator |
68 |
| 338/36 |
Fluid- or gas pressure-actuated |
65 |
| 338/41 |
Bellows or capsule |
10 |
| 338/40 |
Bourdon tube |
4 |
| 338/42 |
Diaphragm |
225 |
| 338/38 |
Liquid resistance element or contact |
21 |
| 338/39 |
Piston |
18 |
| 338/37 |
Vehicle tire inflation |
1 |
| 338/47 |
Force-actuated |
142 |
| 338/34 |
Gas, vapor, or moisture absorbing or collecting |
409 |
| 338/35 |
Humidity |
143 |
| 338/43 |
Gravity stabilized or inertia actuator |
7 |
| 338/45 |
Centrifugal |
1 |
| 338/44 |
Liquid resistance element or contact |
4 |
| 338/46 |
Pendulum |
12 |
| 338/32R |
Magnetic field or compass (e.g., hall effect type) |
554 |
| 338/32H |
Hall effect |
242 |
| 338/32S |
Superconductors |
34 |
| 338/15 |
Photoconductive (e.g., light sensitive) |
81 |
| 338/18 |
Infrared radiation |
58 |
| 338/17 |
Plural resistance elements (e.g., mosaic) |
20 |
| 338/19 |
With transparent housing |
4 |
| 338/16 |
With vibration control |
1 |
| 338/14 |
Plural conditions |
26 |
| 338/7 |
Resistance value temperature-compensated |
54 |
| 338/8 |
Temperature-compensated actuator |
10 |
| 338/9 |
With additional compensating resistor or resistance element |
40 |
| 338/10 |
Filament or wire resistance elements |
4 |
| 338/279 |
Ribbon resistance element bent or curved on flat side |
25 |
| 338/282 |
Helical or wound |
17 |
| 338/280 |
Zigzag or sinuous |
62 |
| 338/281 |
Element includes integral stiffening structure |
25 |
| 338/49 |
Shunt type |
46 |
| 338/2 |
Strain gauge type |
217 |
| 338/5 |
Dynamometer type |
151 |
| 338/6 |
Extensometer type |
39 |
| 338/4 |
Fluid- or gas pressure-actuated |
387 |
| 338/3 |
With temperature compensation |
47 |
| 338/217 |
Tapered element |
46 |
| 338/218 |
Helical or wound |
14 |
| 338/306 |
With base extending along resistance element |
108 |
| 338/314 |
Resistance element and base formed in layers |
264 |
| 338/307 |
Resistance element and/or terminals printed or marked on base |
234 |
| 338/308 |
Resistance element coated on base |
591 |
| 338/309 |
Terminal coated on |
440 |
| 338/310 |
Resistance element extends through base |
24 |
| 338/311 |
Resistance element mounted in a groove in base |
39 |
| 338/313 |
Terminal embraces base |
66 |
| 338/312 |
Terminal extends in or through base |
64 |
| 338/60 |
With capacity-reducing |
9 |
| 338/53 |
With cooling gas or liquid circulation |
25 |
| 338/54 |
Element granular, powdered, or stacked between terminals |
5 |
| 338/57 |
Vented or ventilating casing or housing |
14 |
| 338/58 |
Ventilated helical or zigzag element |
33 |
| 338/55 |
With cooling liquid circulation |
20 |
| 338/56 |
Liquid resistance element circulates |
7 |
| 338/67 |
With diverse nonelectrical device (e.g., mechanical or chemical) |
11 |
| 338/64 |
With electrical shield |
17 |
| 338/65 |
Mechanically variable resistor |
0 |
| 338/51 |
With heat dissipating projections (e.g., vanes) |
51 |
| 338/52 |
Granular, powdered, or transversely stacked resistance element |
5 |
| 338/59 |
With heat-storing |
10 |
| 338/61 |
With inductance-reducing |
34 |
| 338/62 |
Helical or wound element |
9 |
| 338/63 |
Bifilar |
3 |
| 338/222 |
With liquid element |
10 |
| 338/315 |
With mounting or supporting means |
58 |
| 338/316 |
Compensates for or permits resistor |
69 |
| 338/318 |
Extending between supports |
48 |
| 338/319 |
Plural resistors |
49 |
| 338/320 |
Plural resistors |
182 |
| 338/317 |
Threading or projecting through the support |
30 |
| 338/277 |
With protecting structure spaced from element or terminal |
19 |
| 338/215 |
With switch |
33 |
| 338/322 |
With terminal |
105 |
| 338/324 |
Diverse terminals |
65 |
| 338/331 |
Resistance element surrounds terminal |
21 |
| 338/328 |
Terminal and resistance element disposed in flat layers |
146 |
| 338/330 |
Terminal and resistance element integral |
47 |
| 338/327 |
Terminal coated on resistance element |
64 |
| 338/332 |
Terminal embraces or surrounds resistance element |
137 |
| 338/323 |
Terminal tapped on resistance element |
23 |
| 338/326 |
Terminals adjacent (e.g., looped resistor) |
18 |
| 338/329 |
Welded or soldered |
74 |
| 338/325 |
With three or more terminals |
111 |
| 338/DIG.1 |
Worm gear drive |
16 |
| 338/283 |
Zigzag or sinuous resistance element |
51 |
| 338/287 |
Compound or multiple zigzag |
30 |
| 338/288 |
Element includes conductive jumpers or spacers |
10 |
| 338/294 |
Cylindrical |
30 |
| 338/285 |
Element extends along groove in base |
12 |
| 338/292 |
Element forms a coating |
28 |
| 338/289 |
Element includes conductive jumpers or spacers |
17 |
| 338/284 |
Element includes integral stiffening structure |
14 |
| 338/290 |
Element projects in or through an opening or a slot in a support or frame |
24 |
| 338/286 |
Helical |
8 |
| 338/293 |
Planar |
63 |
| 338/291 |
With transverse element stiffening or reinforcing rod or strip |
5 |
