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Improved Magne-Matic" Model
7AuMOa MAGNETIC STIRRERS • Stainless steel housing— corrosion-resistant and stronger than aluminum • More powerful stirring action •
Wider diameter top plate—S inches
Fig. 2.
9235-B10, Fie. 1
Stirrer swings aside to permit convenient removal of vessel containing sample.
A new stainless steel a n d more powerful, extremely efficient model of t h e Magnetic Stirrer introduced b y us in 1944. Drive unit totally enclosed in compact housing of corrosion-resistant stainless steel, stronger t h a n aluminum. Rotating magnetic field spins a magnetized stirring bar, encapsulated in inert plastic, t o stir liquids in open or closed vessels. Speed is rheostat-controlled; operation is quiet and vibration-free. Wide Power Range. These new model stirrers produce vigorous agitation of k liters of 50% glycerol solution (see fig. 3). Positive control of stirring rate, from full speed down t o a few revolutions per second, allows use also for very small volumes or for gentle mixing. Magnetic coupling flux is adequate to stir effectively even in vessels elevated 1 inch above drive unit. Drive Unit. Continuous d u t y motor and driving magnet are encased in housing of heavy gauge stainless steel, 5 inches diameter X 3}4 inches high, with no seams above base. The larger motor of these improved stirrers is of t h e shaded pole t y p e . Bearings are lubricated for long service life. Alnico V driving magnet, %-inch square X 2 inches long, is dynamically balanced on motor shaft. Rubber feet permit use on bench. Freestanding height is 4 inches. S w i n g A r m S u p p o r t . Exclusive feature of Thomas Magne-Matic® Stirrers is t h e attached swivel clamp.
. Fi e ,3. ^ Showing vigorous agitation of ::4;;lit6rs;:of:;^0^: ,iSly^rilii^li. ; J'' :
When mounted on support, stirrer can be raised or lowered on t h e rod, or swung aside for easy removal of vessels from assemblies (see fig. 2 ) . Clamp also permits adjustment of stirrer center in a horizontal plane from 3 to 4 M inches from rod. Particularly convenient in both the mounting and use of t h e closed system assemblies. Stirring Bars, Stirrers supplied a r e Alnico V magnets encapsulated in Teflon, with central pivot ridge t o minimize friction. 9235-B10. M a g n e t i c Stirrer, T h o m a s Enclosed R h e o s t a t Model, as above described; with rheostat in drive unit and speed control knob on front of housing. With two Jii-inch diameter Teflon-coated stirring bars, one 1-inch, t h e other 1 % inches long. With 3-wire cord, 3-prong plug with adapter, for 115 volts, 60 cycles, a . c ; 10 watts 40.40 9235-B20. D i t t o , b u t without stirring b a r s . . . 36.00 9235-B40. M a g n e t i c Stirrer, T h o m a s R e m o t e C o n trol Model, with separate rheostat attached to control unit b y 30-inch connecting cord. With stirring bars as listed above. For 115 volts, 60 cycles, a . c ; 10 watts. 44.40 9235-B50.
D i t t o , b u t without stirring bars
40.00
1 0 % discount in lots of 12 or more.
Bulletin 144, giving detailed information, sent upon request
Thomas
ARTHUR H. THOMAS COMPANY Scientific Apparatus and Reagents VINE S T R E E T AT 3 R D · P.O. BOX 7 7 9 · P H I L A D E L P H I A Circle No. 66 on Readers' Service Card
104 A
·
ANALYTICAL CHEMISTRY
5, PA..
U.S.A.
