1896 



ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 



Fig. 12. (7) A tank filler whicli is so de- 

 signed that it can be attached permanently 

 to the sprayer tank. 



it will not take care of the overflow when 

 both leads of hose are shut off. 



A plunger type of relief valve, which 

 appeared on the market recently, is very 

 sensitive to pressure variation and ap- 

 parently has all ot the requisites of dur- 

 ability. When the pressure becomes 

 great enough to overcome the forcing of 

 a spring, the plunger is raised, uncover- 

 ing a row of holes in the wall of the 

 sleeve, through which the liquid escapes 

 back into the tank. Fig. 9 gives a de- 

 tailed view of its construction. 



Several forms of pressure regulators, 

 on some power and traction machines, 

 automatically throw the pump out of gear, 

 saving power and obviating trouble and 

 danger when all of the pump's capacity 

 is not utilized. This also effects a great 



saving in wear and prevents breaking the 

 machine or straining it unnecessarily. 

 Another form of regulator, which is 

 placed on the suction pipe, shuts off the 

 supply when the pressure becomes suffi- 

 cient to raise the plunger against the 

 spring. This allows the engine to run 

 free, excepting for the vacuum created 

 by the pump in pulling against a reduced 

 opening or shut-off suction pipe, the ex- 

 penditure of power and the wear of the 

 machine being greatly lessened by this 

 little device. 



A special type of pressure regulator, 

 which is placed between the pump and 

 the air chamber, is operated by the liquid, 

 under pressure, raising a diaphram 

 against the spring regulator. The rod 

 attached to the diaphram lifts the ball 

 in the lower valve box, and the upper 

 valve closes automatically. This retains 

 the pressure in the air chamber and al- 

 lows the liquid supplied by the pump to 



Fig. 13. (8) A tank filler which lifts the 

 water above the high ])ressure jet stream. A 

 convenient tank filler which can be left at 

 the filling station. 



