| De Lano | Courtland | dental wax expansion cabinet | 1670026 | Cedar Rapids | 1928 |
| Vesely | Stanley | lifting jack | 1670328 | Cedar Rapids | 1928 |
| Chamberlin | Earl | humidifier | 1692816 | Cedar Rapids | 1928 |
| Bagby | Ralph | dasher for ice cream freezer | 1693016 | Cedar Rapids | 1928 |
| Waggoner | Melancthon | switching means for effecting electrotherapeutic treatment | 1693734 | Cedar Rapids | 1928 |
| Ronk | George | trailer for self propelled vehicles | 1693869 | Cedar Rapids | 1928 |
| Reid | Raymond | grinder and polisher | 1655565 | Cedar Rapids | 1928 |
| Schmidt | George | awning protector | 1681016 | Cedar Rapids | 1928 |
| McDonnell | George | pipe flange tool | 1681126 | Cedar Rapids | 1928 |
| Rodgers | Chesley | tourist's combination cabinet | 1681685 | Cedar Rapids | 1928 |
| Gantz | Amos | ice cream brick cutter | 1661533 | Cedar Rapids | 1928 |
| Bagley | Ralph | direct expansion ice cream freezer | 1709454 | Cedar Rapids | 1929 |
| Boileau | Arthur | folding mechanism for cartoning machines | 1724124 | Cedar Rapids | 1929 |
| Roushar | Joseph | magazine and book rack | 1725422 | Cedar Rapids | 1929 |
| Koutnik | Sylvester | magazine and book rack | 1725422 | Cedar Rapids | 1929 |
| Stusak | Louie | adjustable chair | 1725427 | Cedar Rapids | 1929 |
| Boyce | Charles | finishing prints | 1725699 | Cedar Rapids | 1929 |
| Ronk | George | operating mechanism for ditching machines and their carrier cars | 1726771 | Cedar Rapids | 1929 |
| Inskeep | Alice | music instruction device | 1713282 | Cedar Rapids | 1929 |
| Archibald | John | signaling device | 1715265 | Cedar Rapids | 1929 |
| Loufek | Charles | capping machine | 1696961 | Cedar Rapids | 1929 |
| Naibert | Frank | vacuum skin cleanser | 1732310 | Cedar Rapids | 1929 |
| Ronk | George | fair leader | 1732485 | Cedar Rapids | 1929 |
| Ronk | George | ditcher carrier | 1698172 | Cedar Rapids | 1929 |
| Stusak | Louie | furniture press | 1733284 | Cedar Rapids | 1929 |
| Brownlee | Harold | manufacturing furfural | 1735084 | Cedar Rapids | 1929 |
| Wilson | Clement | clinching press | 1735625 | Cedar Rapids | 1929 |
| Batchelder | Harrison | pipe | 1736819 | Marion | 1929 |
| Klemish | Leon | closet bowl ventilator | 1700936 | Marion | 1929 |
| Lowe | Walter | closet bowl ventilator | 1700936 | Marion | 1929 |
| Ronk | George | carriage for excavator buckets | 1701013 | Cedar Rapids | 1929 |
| Le Febure | Leo | binder tray | 1736925 | Cedar Rapids | 1929 |
| Le Febure | Leo | binder tray | 1736926 | Cedar Rapids | 1929 |
| Fuhrman | Herman | valve seating tool | 1715546 | Marion | 1929 |
| Patterson | Walter | combination woodworking machine | 1715564 | Cedar Rapids | 1929 |
| Lewis | Harry | purifying anthraquinone | 1701186 | Mount Vernon | 1929 |
| Snouffer | Frank | portable tent | 1701428 | Cedar Rapids | 1929 |
| Huntington | James | expansion joint installing device | 1768689 | Cedar Rapids | 1930 |
| Huntington | James | expansion joint installing device | 1768690 | Cedar Rapids | 1930 |
| Dunn | Allen | apparatus for truing valve seats | 1747060 | Cedar Rapids | 1930 |
| Kehoe | Barney | combination lamp base and sign | 81697 | Cedar Rapids | 1930 |
| Gordon | Gerald | motor heating and cooling system | 1749424 | Marion | 1930 |
| Franklin | Ray | hog feeder | 1772843 | Cedar Rapids | 1930 |
| Rickey | Jesse | hog feeder | 1772843 | Cedar Rapids | 1930 |
| Ronk | George | machine part | 1775295 | Cedar Rapids | 1930 |
| Reid | Raymond | sanding machine | 1776450 | Cedar Rapids | 1930 |
| Wagner | Clinton | wrench | 1753223 | Cedar Rapids | 1930 |
| Wagner | Clinton | wrench | 1753224 | Cedar Rapids | 1930 |
| Smith | Edmund | automatic washer | 1755154 | Springville | 1930 |
| Smith | Sheldon | automatic washer | 1755154 | Springville | 1930 |
| Ronk | George | machine frame | 1756387 | Cedar Rapids | 1930 |
| Rowe | Clell | meat washing machine | 1756517 | Cedar Rapids | 1930 |
| Knight | Floyd | meat washing machine | 1756517 | Cedar Rapids | 1930 |
| Lattner | Paul | heat conducting means for steam generators or fluid heaters | 1782171 | Cedar Rapids | 1930 |
| Cail | George | spring hanger | 1832617 | Cedar Rapids | 1931 |
| Garnett | Robert | rolling hinge gear | 1833159 | Cedar Rapids | 1931 |
| Palmer | George | clamp | 1811518 | Cedar Rapids | 1931 |
| Ronk | George | clutch control device | 1834222 | Cedar Rapids | 1931 |
| Reinking | Alfred | creosoted wood culvert | 1834643 | Cedar Rapids | 1931 |
| Figg | Herbert | churn | 1794680 | Cedar Rapids | 1931 |
| Smith | Sheldon | eyeshade | 1794927 | Springville | 1931 |
| Smith | Edmund | eyeshade | 1794927 | Springville | 1931 |
| Ronk | George | bearing for cable drums and the like | 1836339 | Cedar Rapids | 1931 |
| Renk | George | shoe for tractor treads | 1795618 | Cedar Rapids | 1931 |
| Prucha | Joseph | emergency box | 1839051 | Cedar Rapids | 1931 |
| Prucha | Alois | emergency box | 1839051 | Cedar Rapids | 1931 |
| Carson | Hiram | gas fired water heater | 1816419 | Cedar Rapids | 1931 |
| Fordyce | Edward | change speed device | 1800062 | Cedar Rapids | 1931 |
| Steele | Ray | engine piston | 1822322 | Cedar Rapids | 1931 |
| Boyce | Charles | method of and apparatus for making and finishing prints | 18191 | Cedar Rapids | 1931 |
| Boyce | Charles | finishing prints | 18192 | Cedar Rapids | 1931 |
| Hetherington | Edwin | child's teeter board | 1858892 | Cedar Rapids | 1932 |
| Agnew | Will | battery terminal connecter | 1861290 | Walker | 1932 |
| Fox | Merritt | humidifier | 1861340 | Cedar Rapids | 1932 |
| Mueller | Charles | device for destroying mites on fowls | 1861353 | Cedar Rapids | 1932 |
| Marshall | Frank | hose reel | 1886207 | Center Point | 1932 |
| Marshall | Clyde | hose reel | 1886207 | Cedar Rapids | 1932 |
| Hawks | Estus | material spreader | 1862347 | Cedar Rapids | 1932 |
| Rickey | Jesse | stanchion | 1886741 | Cedar Rapids | 1932 |
| Choate | Roy | track laying belt | 1862784 | Cedar Rapids | 1932 |
| Haskell | Willis | heat radiating device for gas furnaces | 1862892 | Cedar Rapids | 1932 |
| Steel | Ray | wrist pin | 1887964 | Cedar Rapids | 1932 |
| Steele | Ray | engine piston | 1888203 | Cedar Rapids | 1932 |
| Baumgartner | Floyd | mechanical teeing device | 1888256 | Cedar Rapids | 1932 |
| Slauson | Stephen | clothes drying rack | 1839607 | Cedar Rapids | 1932 |
| Hasek | Victor | collapsible wallet | 1839758 | Cedar Rapids | 1932 |
| Tokheim | John | Control valve for volatile liquid storage tanks | 1890870 | Cedar Rapids | 1932 |
| Frazee | Walter | apparatus for mixing material for making roads | 1867739 | Cedar Rapids | 1932 |
| Ronk | George | tractor tread | 1891556 | Cedar Rapids | 1932 |
| Kubias | Lillian | signaling device for automobiles | 1841826 | Cedar Rapids | 1932 |
| Frazee | Walter | apparatus for mixing materials for making roads | 1867817 | Cedar Rapids | 1932 |
| Finson | Edwin | operation table for animals | 1842015 | Central City | 1932 |
| Clendening | Karl | broom | 1842896 | Cedar Rapids | 1932 |
| Hageman | Ralph | gas burner | 1843361 | Cedar Rapids | 1932 |
| Kinsley | Jason | razor blade holder | 1847765 | Cedar Rapids | 1932 |
| Tokheim | John | portable device for removing impurities from storage tanks | 1844614 | Cedar Rapids | 1932 |
| Reid | Raymond | sanding machine | 1872502 | Cedar Rapids | 1932 |
| Buresh | George | safety device for automobiles | 1848313 | Cedar Rapids | 1932 |
| Boileau | Arthur | aerating means for freezers and the like | 1907486 | Cedar Rapids | 1933 |
| Keller | John | automatic door closer | 1908706 | Alburnett | 1933 |
| Border | Harley | automatic door closer | 1908706 | Alburnett | 1933 |
| McGuire | William | bearing | 1909624 | Cedar Rapids | 1933 |
| Gorman | Catherine | hair band | 1914252 | Cedar Rapids | 1933 |
| Scheer | Charley | combined safety razor and stropper | 1916936 | Cedar Rapids | 1933 |
| Brownlee | Harold | manufacturing furfural | 1919877 | Cedar Rapids | 1933 |
| Brownlee | Harold | manufacturing furfural | 1919878 | Cedar Rapids | 1933 |
| Choate | Roy | hydraulic hoist | 1892829 | Cedar Rapids | 1933 |
| Ridge | Hayes | vehicle bumper | 1925461 | Cedar Rapids | 1933 |
| Choate | Roy | dump wagon | 1925654 | Cedar Rapids | 1933 |
| Choate | Roy | draft appliance | 1893983 | Cedar Rapids | 1933 |
| Kesler | Carl | varnish | 1894374 | Cedar Rapids | 1933 |
| Boileau | Arthur | butter wrapping machine | 1927011 | Cedar Rapids | 1933 |
| Musgrave | Claude | automobile brake testing device | 1929149 | Cedar Rapids | 1933 |
| Dilger | Herman | bowl and spindle connection for centrifugal liquid separators | 1896665 | Cedar Rapids | 1933 |
| Scott | Allan | tube feeder and cutter | 1967374 | Cedar Rapids | 1934 |
| Boileau | Arthur | design for a pasteurizer | 92698 | Cedar Rapids | 1934 |
| Main | Willard | design for a vending machine | 92914 | Cedar Rapids | 1934 |
| McFadden | William | surgical instrument | 1943543 | Cedar Rapids | 1934 |
| Thousand | Adolph | air conditioning device | 1973233 | Cedar Rapids | 1934 |
| Rodler | Waldo | hydraulic control device | 1974657 | Cedar Rapids | 1934 |
| Doege | John | wrench | 1976279 | Cedar Rapids | 1934 |
| Boileau | Arthur | liquid treating and bottling apparatus | 1976768 | Cedar Rapids | 1934 |
| Boyce | Charles | apparatus for producing and finishing prints | 1978405 | Cedar Rapids | 1934 |
| Boyce | Charles | treating surfaces of fibrous materials | 1978406 | Cedar Rapids | 1934 |
| Carson | Hiram | making blue and carbureted water gas | 1952654 | Cedar Rapids | 1934 |
| Ronk | George | supplemental tread belt mechanism for tractors | 1952894 | Cedar Rapids | 1934 |
| Haskell | Willis | gas burner | 1952919 | Cedar Rapids | 1934 |
| Carson | Hiram | carbureted water gas process | 1953848 | Cedar Rapids | 1934 |
| Tokheim | John | fire screen unit for volatile liquid storage receptacles | 1983417 | Cedar Rapids | 1934 |
| Lattner | Emert | fan or blower for fuel burners | 1955852 | Cedar Rapids | 1934 |
| Mundt | Robert | expanding pistons | 1983673 | Cedar Rapids | 1934 |
| Davin | Thomas | earth moving device | 1956007 | Cedar Rapids | 1934 |
| Weber | Michael | earth moving device | 1956007 | Cedar Rapids | 1934 |
| Knight | Floyd | vegetable washer | 1999814 | Cedar Rapids | 1935 |
| Thousand | Adolph | air conditioning device | 2002023 | Cedar Rapids | 1935 |
| Boyce | Charles | composition for coating sheets, fibrous stocks, and the like | 2003065 | Cedar Rapids | 1935 |
| Stark | Leo | design for a burner | 94317 | Cedar Rapids | 1935 |
| Lanko | Ernest | animal trap | 2009320 | Springville | 1935 |
| Rodler | Waldo | earth moving device | 2011191 | Cedar Rapids | 1935 |
| Choate | Roy | earth moving device | 2011191 | Cedar Rapids | 1935 |
| Hargrave | Fred | disk grinding machine | 2014327 | Cedar Rapids | 1935 |
| Ford | Patrick | door lock | 2016895 | Cedar Rapids | 1935 |
| Rosendahl | Nils | conveyer | 2014636 | Cedar Rapids | 1935 |
| Rodler | Waldo | wagon | 2023700 | Cedar Rapids | 1935 |
| Knight | Floyd | green corn husking machine | 2037661 | Cedar Rapids | 1936 |
| Baker | Walter | excavating shovel | 2037958 | Cedar Rapids | 1936 |
| Bell | James | ladder | 2038521 | Cedar Rapids | 1936 |
| McIlvain | Earl | piston | 2040032 | Cedar Rapids | 1936 |
| Steele | Ray | piston | 2040032 | Cedar Rapids | 1936 |
| Dunn | Allen | chuck | 2040601 | Cedar Rapids | 1936 |
| Greer | Edward | vehicle | 2042780 | Cedar Rapids | 1936 |
| Johnson | Harry | communication system | 2044305 | Cedar Rapids | 1936 |
| Rosendahl | Nils | bearing and oiling system therefor | 2045026 | Cedar Rapids | 1936 |
| Rosendahl | Nils | oiling system | 2046092 | Cedar Rapids | 1936 |
| Austin | Ellsworth | pump | 2046103 | Cedar Rapids | 1936 |
| Choate | Roy | endless track structure | 2050274 | Cedar Rapids | 1936 |
| McFadden | William | electrical connecter | 2050440 | Cedar Rapids | 1936 |
| Webber | Clare | float | 2051281 | Cedar Rapids | 1936 |
| Austin | Ellsworth | earth moving device | 2051283 | Cedar Rapids | 1936 |
| Green | Howard | sedimentation tank | 2052091 | Cedar Rapids | 1936 |
| Franklin | Ray | washing machine | 2054797 | Cedar Rapids | 1936 |
| Clendening | Karl | starch mill reel | 2055119 | Cedar Rapids | 1936 |
| Lehmann | Charles | radio antenna | 98652 | Cedar Rapids | 1936 |
| Chamberlin | Earl | air conditioning device | 2055621 | Cedar Rapids | 1936 |
| Tokheim | John | apparatus for unloading liquid containers | 2055954 | Cedar Rapids | 1936 |
| Austin | Ellsworth | snow moving device | 2101666 | Cedar Rapids | 1937 |
| Lattner | Emert | oil burner | 104271 | Cedar Rapids | 1937 |
| Campbell | Frank | vented nozzle | 2102786 | Cedar Rapids | 1937 |
| Lattner | Emert | oil burner | 104378 | Cedar Rapids | 1937 |
| Tucker | Irvin | design for a combined gas dispenser and canopy | 104889 | Cedar Rapids | 1937 |
| Fontana | Christopher | oil burner | 105093 | Cedar Rapids | 1937 |
| Fisher | Paul | bread rack | 105212 | Cedar Rapids | 1937 |
| Fisher | Paul | bread rack | 105483 | Cedar Rapids | 1937 |
| Hageman | Ralph | burner | 2075278 | Cedar Rapids | 1937 |
| Dunn | Allen | torque measuring wrench | 107311 | Cedar Rapids | 1937 |
| Foster | Everette | microphone plug | 2081622 | Cedar Rapids | 1937 |
| Kinsley | Jason | abrasive compound and utilizing same | 2084644 | Cedar Rapids | 1937 |
| Boileau | Arthur | safety device for ice cream freezers and the like | 2085291 | Cedar Rapids | 1937 |
| Slife | Ralph | shifting device for tractor cultivators | 2089137 | Springville | 1937 |
| Dunn | Harry | shifting device for tractor cultivators | 2089137 | Marion | 1937 |
