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Westclox Electric Clock Motor History

Westclox Motor S1, Sangamo Self Starting

The back of the Sangamo motor with its three mounting holes
Inside the Sangamo motor showing the poles, and the bearing hole for the rotor.
Side of the Sangamo motor showing the copper induction rotor which provides the starting and running torque. The copper rotor has a brass pinion which turns a fiber gear in the clock movement.
Inside the copper rotor showing the permanently magnetized rotor that maintains synchronism with the A/C and limits the speed of the induction rotor.

Westclox Electric Clock Motor Types

S1 Self-starting motor made by Sangamo Electric Co., Springfield, Illinois. Has 2 rotors on one shaft: induction rotor provides starting and running torque, permanently magnetized rotor maintains synchronism with the A/C and limits the speed of the induction rotor. Patent #1,933,591. Used on Westclox clocks 1931 - ca. 1940.
S2 Manual-start motor designed and made by Western Clock Co. Patents 1,957,281 and 2,046,130. Used from 1932 - 1942.
M1 Self-starting motor designed and made by Western Clock Co. Large rotor contained between plates, field coil located away from rotor to keep the bearings cool. Patent #2,015,042. Used from 1938 until ca. 1940. Developed by Oscar Kamisky and Joseph Reinhardt.
M2, M3 Smaller version of M1. M2 and M3 are same basic motor, mounted differently. M2: movement plates far apart with motor set in flush. M3: movement plates close together with motor behind, a more compact arrangement. Patents 1,935,208; 1,977,184; 1,977,186; and 2,015,042. Used from 1940 until sometime in the mid 1950's.
M4 Self-starting motor with exposed rotor. Coil assembly is a cylindrical unit with the rotor pivoted on axis of the assembly. Patents 2,537,093 and 2,704,432. Used from 1948 through the early 1960's. Some have a cover over the rotor.
M5 Sealed rotor detachable from coil assembly. Introduced in the late 1950's.

History of Westclox Synchronous Electric Clocks


General Time Instruments Corporation (which had been formed in 1930 as a holding company for Western Clock Company and Seth Thomas) purchases the Hamilton-Sangamo Corporation.

Quoting from "Illinois Horology" by Andrew Hayes Miller and Dalia Maria Miller, p. 51, regarding the Sangamo Electric company:

"To meet the synchronous clock competition, they developed a non self starting synchronous motor during the spring of 1930. In August, a new line of clocks was ready for market. According to Robert C. Lanphier in Forty Years of Sangamo:

""However, we soon realized that we needed a self-starting synchronous clock, so later that year produced the first type "F" self-starting motor. . .We were about to offer a line of self starting clocks. . . . when, in December 1930, the General Time Instruments Corporation . . . owning the Western Clock company ("Big Ben") and Seth Thomas Clock Company expressed an interest in using the type "F" motor in their electric clocks. As we could not sell motors to any other concern than Hamilton-Sangamo, the upshot of the matter was that Mr. Ralph Matthiessen, President of G.T.I. corporation, offered to buy the Hamilton-Sangamo Corporation, and thus obtain the exclusive rights to use all of our motors, A.C. and D.C., for clock purposes, as well as the established business of the Hamilton-Sangamo Corporation. The business was therefore sold to G.T.I. Corporation in April, 1931, and Hamilton and Sangamo retired from the clock business, with considerable loss, but with much valuable experience.""

1931 First A/C powered clocks put on market. These clocks used the S1 self-starting synchronous motor, purchased from Sangamo. The first of these clocks were Big Ben models: Model 820, black composition (Bakelite) case, $8.75, Model 830, same but with luminous dial, $10.00, both made from 1931 - 1934; and model 840, mahogany case, $12.50 retail (by 1935 the price had been reduced to $5.95), made from 1931 - 1935. Other clocks which used the Sangamo motor include Ben Franklin (1935 - 1939), Greenwich (1936 - 1939) and Silent Knight (1936 - 1940).
1932 Westclox designed manual start synchronous motor, S2, introduced. Entire movement except coil manufactured in the LaSalle plant. This manual start motor was made for many years. Production apparently ceased during World War II, and never resumed. Clocks using this motor include Electric Wall Clock - rectangular case with rounded corners (1932 - 1939), America Electric (1932 - 1936), Ben Bolt (1933 - 1939), Country Club (1935 - 1942), Electric Wall Clock - round case (1936 - 1939), Andover (1938 - 1942), Orb (1938 - 1940), and Belfast (1939 - 1942).
1936 Name "Western Clock Company" changed to "Westclox"
1938 Motor type M1 introduced - Westclox own design of self-starting synchronous motor. Clocks using this motor included Bachelor (1938 - 1947), Manor (1938 - 1947), Big Ben style 5 Chime Alarm (1938 - 1941), Pittsfield (intoduced 1939). Note: Bachelor, Manor, and Pittsfield used type M2 motor starting ca. 1940.
1940 Smaller version of Westclox self-start synchronous motor introduced - types M2 and M3. Some of the models which used these motors are: Baby Ben Style 5 Electric (intoduced 1940), Big Ben Style 5 Electric (not Chime Alarm) (intoduced 1941), Dunbar (1946 - 1952), Logan (intoduced 1946), Big Ben electric in rectangular brown Bakelite case (1947 - 1952), Oracle (intoduced 1947), Moonbeam - flashing light alarm clock (intoduced 1949), and Switch Clock appliance timer (intoduced 1949).
1948 Motor type M4 introduced. Used in Belfast (intoduced 1948), Barry (intoduced 1948), Bantam (intoduced 1949), Greenwich (1950 - 1954), Melody (intoduced 1950), Glo-Larm (intoduced 1953), Ardmore, Orb, Big Ben and Baby Ben Style 7 electric (intoduced 1956), and many other models.
Late 1950's Motor with sealed rotor (detachable from field coil) introduced (M5).
Misc. Electric Information
1935 Stromberg Electric Company purchased
? Haydon Manufacturing Co. was purchased by General Time prior to 1947 (don't know what year). Does this relate to their use of Haydon electric motor patents?
Electrically Wound Clocks, Auto Clocks and the Sterling Clock Company

Quote from September 13, 1927 monthly report from general manager to board of directors: "Work on electric clocks has been progressing and four applications for patents of Electric clocks have been filed by our men."


Quote from February 19, 1929 annual report from the general manager to the Board of directors: "In accordance with appropriation made by the Board April 10, 1928, we acquired the patents and patent applications owned by William H. Greenleaf for $50,000, and an agreement was entered into whereby Mr. Greenleaf will be employed by us for a period of five years at a salary of $10,000 per year, during which time any patents he may produce will be assigned to us."

Sterling Clock Co. (Meridan, CT) purchased by Western Clock Company and moved to LaSalle. (They were a maker of electrically wound automobile clocks).

Quote from February 19, 1929 annual report from Western Clock Co. General Manager to Board of Directors: "On May 21, 1928, we purchased the outstanding Common and Preferred Stock of the Sterling Clock Company, for the sum of $261587.65. The machinery, tools, etc. have been moved here and installed in our factory, having been purchased by this Company at the book value of $63099.38."

"Considerable progress has been made in the development of this division and we are now producing the Sterling Electric Auto Clock, using our own watch parts instead of the Waterbury watch parts used formerly. These auto clocks are being sold to the Sterling Clock Company under agreement we have with them."

"Our Experimental Department has developed a number of models of electric clocks, with the idea of improving the electric clock now being manufactured for the Sterling Clock Company. We are also working on models of electric house clocks."

Quote from February 19, 1929 annual report of President to shareholders:

"Through these purchases your Company has acquired patents and a going electric clock business with an established market of approximately 30000 clocks per year. The Sterling Clock Company was located in Meridan, Connecticut, but this factory was closed shortly after our purchase and the entire machinery and tools moved to La Salle. It is now installed in our factory here as a special department."

"Due to defects in management and defects in the product itself, the reputation of the Sterling Clock Company in the trade was not all that we might have wished. We feel that these defects in management have now been overcome and the mechanical defects in the clock itself are slowly being bettered under our production methods, so that it will not be long before we can consider this electric clock as up to the standard of the rest of our products."

"Our experimental Department is continuing to develop new models of electric clocks, with the idea that it may discover a better clock than the one that we are producing. They are also working on a model of an electric house clock to be run by a battery."

1929 First Sterling electric clocks sold that could be fitted in any car. The dials are marked Sterling Electric. Before this time most of the product was sold directly to auto manufacturers.

The October 20, 1928 Tick Talk quotes from the October 6, 1928 Meridan Record: "The Sterling Clock Company, which was purchased some time ago by the Western Clock Company of La Salle, Illinois, is to close its local plant about the middle of this month, and the entire equipment of the factory will be moved to La Salle, where the main factory of the company is located. "The Sterling Clock company is now employing about forty-five hands and all will be continued in the employ of the company until the day of closing. The purchaser of the business, the Western Clock Company, is one of the large clock makers of the country - manufacturers of Big Ben and Baby Ben alarm clocks. "The Sterling Clock Company came here in December, 1926 and took a three year's lease on the old Parker factory on West Main Street, and purchased the machinery in the factory. Shortly afterwards it moved its entire business here from New York and engaged extensively in the manufacture of electric automobile clocks."

Sources: company chronology compiled by Westclox, Westclox price change list in the possession of Ellworth Danz, and the company magazine Tick Talk unless otherwise stated.

Compiled by Richard Tjarks and Bill Stoddard.

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