VERTICAL SECTION.
Fig. 149.
This cylinder is loaded with weights marked to indicate the pressure which the accumulator will balance with those weights in use. The water is pumped into the bottom through the pipe C, and fills the annular space around the spindle. The entire weight of cylinder is raised by the pressure of water acting only on the area of the end of brass sleeve D D, which is only 1⁄2 inch thick all around the center spindle, and extends down through the bottom packing in cylinder, as shown in sectional view. Fig. 149.
A compact arrangement is thus gained and any reasonable, required cubical capacity may be reached by lengthening the stroke.
The accumulator is supplied by two pumps having plungers 13⁄8″ diam. by 31⁄2″ stroke, speed 100 to 120 rev. per minute.
When the loaded cylinder B reaches the top of its stroke, by means of a small chain it closes the suction cock E, which shuts off the water supply of the pumps.
To put in a new bottom packing, the cylinder is let down to rest on the wooden blocks G, and the spindle is lifted out of its tapered seat at the bottom by a tackle hooked into the eye-bolt at the top. To renew the top leather the bracket holding the top end of spindle A, has to be removed.
This accumulator (having only a small area) falls quickly when the water is withdrawn, thus producing a combined blow and squeeze, which is of great advantage in hydraulic riveting.
The Hydraulic Intensifier is a cylinder having two diameters, in principle very like the tandem compound engine. It is used for increasing the pressure of water in hydraulic mains, pipes, or machines, using only the energy of the pressure water to effect the change. But for this distinction a steam pump would be an intensifier. An intensifier worked the reverse way is a “diminisher” as a hydraulic pump usually is, giving a reduced pressure.
The intensifier is in some respects analogous to the electric transformer.
The intensifier as used in connection with hydraulic apparatus was patented in the year 1869 by Mr. Aschroft, but the principle upon which it works is very much older. Intensifiers are made both single and double acting.