US Patent: 491,222 
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| Wrench
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	        Patentee:
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 | Auguste Pellet (exact or similar names) - New York, NY |  
 
 
 
 
 
| Manufacturer: |  
| Not known to have been produced |  
 
 
 
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        Patent Dates:
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| Applied: | 
Dec. 02, 1892 | 
 
| Granted: | 
Feb. 07, 1893 | 
 
 
 
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		  Patent Pictures:
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Auguste Pellet patent February 7, 1893  |  
 
USPTO (New site tip) Google Patents 
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                        Stan Schulz 
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        Description: |  
| The position of the adjustable jaw is controlled by incompressible fluid, based on the same principle as a hydraulic jack.  The key element is two chambers in the cylindrical handle, with a valve between the chambers.
An internal compression spring will close the jaws if the release valve between the chambers is operated; the jaws would have be be opened manually with the release valve opened. 
The movable jaw is equipped with a pipe gripping surface that can be swung into position. |  
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