diffusion pump
Date1948-1960
Inventory Number1998-1-0117
ClassificationVacuum Pump
Subject
Maker
Distillation Products Industries
founded 1930
Cultural Region
Place of Origin
Dimensions9.9 x 20.7 x 16.5 cm (3 7/8 x 8 1/8 x 6 1/2 in.)
DescriptionThe device consists of two metal cylinders (one taller and considerably wider than the other) affixed to a wide hollow, metal cylinder. A thin but sturdy metal tube (a refrigeration coil) is wrapped around the two cylinders and is currently closed at both ends with old foam pad kept in place by copper wires. The entire device except for brass sleeves at the top of each cylinder has been painted grey.
On opposite sides of the bottom cylinder the device has extensions with a pair of screw and washer at each end, probably to mount it.
The instrument has a large plaque in front of the bottom cylinder, kept in place by metal wire that goes around its back.
On opposite sides of the bottom cylinder the device has extensions with a pair of screw and washer at each end, probably to mount it.
The instrument has a large plaque in front of the bottom cylinder, kept in place by metal wire that goes around its back.
Signedon plaque: DISTILLATION PRODUCTS / INDUSTRIES / ROCHESTER, NEW YORK / TYPE VMF10-01
Inscribedon plaque below signature: HEAT 135 WATTS / FLUID REQUIRED 55 C.C. -0CT. / REQ'D FORE PRESSURE 100 MICRONS / AIR [empty] C.F.M. [empty] WATER .1 G.P.M. / PATENTED UNDER ONE OR MORE / OF U.S. PATENTS 2080421, 2150676, / 2153189, 2395552, 2435686
Curatorial RemarksFrom the patent numbers listed, this pump is dated after 1948. One of the patents displays good information about this device. To read it, go to the following <a href="http://www.google.com/patents?id=caVWAAAAEBAJ&pg=PA1&dq=2,395,552&source=gbs_selected_pages&cad=1#v=onepage&q=&f=false" target="_blank">website</a>.
FunctionThis is an oil diffusion pump, a type of vacuum pump that is able to attain a much higher vacuum than traditional mechanical pumps. They function as an additional stage between the system to be evacuated and a mechanical vacuum pump.
Diffusion pumps are a critical technology for attaining the high vacuums required for many important 20th-century technologies such as vacuum tubes, cyclotrons and electronics.
The diffusion pump has no moving parts (one of its advantages) and can be even made of glass, although most tend to be in metal.
In diffusion pumps, a stream of molecules of a material (in this case oil) is forced in one direction inside a tube. This stream forces the air molecules away from one of the ends of the tube (the inlet) towards the other end (the outlet). The stream of oil molecules is produced by heating it up, and the oil must be continually condensed as it touches the walls to keep the high vacuum. For this reason the system is surrounded by cooling coils through which water would circulate.
Since this pump is made of metal, it is not possible to see its interior. However, there are two diffusion pumps in the collection that illustrate how this one may work: one is a similar version to this one that has been sliced open (1996-1-0281b), and another which is made entirely of glass (1998-1-0034).
Diffusion pumps are a critical technology for attaining the high vacuums required for many important 20th-century technologies such as vacuum tubes, cyclotrons and electronics.
The diffusion pump has no moving parts (one of its advantages) and can be even made of glass, although most tend to be in metal.
In diffusion pumps, a stream of molecules of a material (in this case oil) is forced in one direction inside a tube. This stream forces the air molecules away from one of the ends of the tube (the inlet) towards the other end (the outlet). The stream of oil molecules is produced by heating it up, and the oil must be continually condensed as it touches the walls to keep the high vacuum. For this reason the system is surrounded by cooling coils through which water would circulate.
Since this pump is made of metal, it is not possible to see its interior. However, there are two diffusion pumps in the collection that illustrate how this one may work: one is a similar version to this one that has been sliced open (1996-1-0281b), and another which is made entirely of glass (1998-1-0034).
Distillation Products Industries
Date: 1930-1950
Object number: 1996-1-0281a,b,c
Distillation Products Industries
Date: circa 1940
Object number: 1998-1-0034
Tigrett Industries Toy Division
Date: 1950-1960
Accessories: cardboard box
Object number: RS1423
ECO Motor Industries Ltd.
Date: circa 1976
Accessories: box; brochure of <i>Stirling Hot Air Engine</i>
Object number: DW1978
Robinson Foster Electric Railway Motor Company
Date: circa 1899
Object number: 1997-1-0542
W.G. Pye & Company, Ltd.
Date: circa 1920
Accessories: 5 accessory parts:
2 magnetic rods with spherical ends;
one brass notch;
needle with tip inserted into cork;
Object number: 1997-1-0662
Walter Hibbert
Date: early 20th Century
Accessories: 7 accessory parts:
2 magnetic rods with spherical ends;
4 brass notches;
needle with tip inserted into cork;
Object number: 1997-1-0661
ACME Apparatus Company
Date: 1930-1950
Accessories: handle; black cylindrical component; wrapping newspaper
Object number: 1997-1-0516
Reynolds Metal Company
Date: circa 1944
Accessories: see Description for itemized list
Object number: 1997-1-0796a
Reynolds Metal Company
Date: circa 1944
Accessories: see Description for itemized list
Object number: 1997-1-0796b
Reynolds Metal Company
Date: circa 1944
Accessories: see Description for itemized list
Object number: 1997-1-0796c
