CENCO hydraulic press, partial
Date: circa 1930
Inventory Number: 2008-1-0181
Classification: Hydraulic Pump
DescriptionHand-operated steel and iron pump supported by a four-legged iron base.
Directly on top of the base are one large and one small cylinder connected by a rectangular open oil well. Near the well is a cross-shaped steel knob. A Steel and wood handle is attached both to the the piston rod extending from the smaller cylinder, and to a rectangular steel hinge near the larger cylinder. A diamond-shaped iron plate, with holes at two points and semicircular cutouts at the other points, sits on top of the large steel piston rod inside the larger cylinder.
A pressure gauge with values ranging from 0 to 1500 is attached to a pipe extending horizontally from the larger cylinder.
The instrument as photographed is incomplete. The full assembly would also include: a thin cover for the oil well; two steel rods to be inserted through the holes in the diamond-shaped plate and fixed within the circular holes near the base of the larger cylinder; an additional U-shaped iron piece to be clamped to the top of the diamond-shaped plate; and a pointed piece of iron to be positioned around and near the top of the two steel rods.
According to the 1930 Central Scientific Company catalog (see primary sources), a pressure gauge graduated to 2500 pounds per square inch was included with the hydraulic pump. This suggests that the present pressure gauge may be a replacement.
Signedon metal plate screwed to base of pump: CENTRAL SCIENTIFIC CO. / [CENCO trademark] / LABORATORY SUPPLIES / APPARATUS CHEMICALS / CHICAGO U.S.A. ;
printed on face of pressure gauge, top center: THE NORWALK IRON WORKS CO. / SOUTH NORWALK, CONN. ;
printed on face of pressure gauge, bottom center: [CROSBY STEAM GAGE AND VALVE CO. trademark]
Inscribedprinted on face of pressure gauge, bottom center: HYDROSTATIC ;
printed on face of pressure gauge, bottom center: PAT. JULY 3 1894 / PAT. FEB. 20. 1900 / 522 618
FunctionFor use in laboratory demonstrations, to display the force generated by a hydraulic pump system.
Moving the handle up and down activates the smaller piston, transferring oil from the rectangular well into the larger piston. The larger piston cylinder rises as the pressure increases. For dramatic effect, the demonstrator could insert a piece of wood or other material inserted between the pointed iron piece (not shown; see description) and the iron plate on top of the larger piston cylinder. As the top of the piston cylinder reached the point, the specimin material would be crushed.
Related Works"Hydraulic Press, Cenco Design, with Pressure Gage." Central Scientific Company Catalog F: Physical Apparatus and Instruments 171 (May 1, 1930): 140.