Sargent & Greenleaf, Rochester, New York - 3 movements, Model Triple A, v.1, v.2 and mounted to Burton-Harris #0 bolt motor

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Yale's 1888 introduction of the Type B and Type C time locks with their three semi-modular movements was quickly recognized as a major advance, and in 1889 Sargent & Greenleaf began offering the Triple A, B, and C time locks, Sargent's first modular three-movement design. These Sargent Triples used three seventy-two hour "L"-sized movements in a gold-plated, jeweled bronze case, but unlike truly modular movements, they were position specific. On each movement, three small set pins on the interior case back align with holes in the movement's back plate, ensuring that only position-one movements fit into the first position, and so forth. The Triple A, B, and C were substantially similar in most respects, with the Triple A designed for use with an automatic, the Triple B with a bolt dog and the Triple C with a side bolt-engagement  extension. A smaller format Triple D entered production around 1896.

Each Sargent Triple employed a spring-loaded snubber bar that was in the first few years of production, nickel-plated and engraved. On the Triple A, the snubber runs along the case bottom to actuate an automatic, commonly the Burton-Harris automatic shown here, and was held in place by the snubber bar guide that bore the patent dates. This guide located at the bottom left of the case, was possibly an anti-dynamite device, working with the adjustable tab and set pin under the center movement to keep the snubber bar from being pushed too far to the right or thrown out, off its mounting rail. The Triple A also featured winding eyelets through the rectangular door glass. (3)

The triple A series was produced from 1889 through 1922 concurrently with the model B and C.


The Burton-Harris #0 bolt motor was the most powerful bolt motor supplied to S&G at this time. The average power of the locking springs is 350 lbs., and that of the unlocking springs 500 lbs. The #0 will operate 18 to 24 ordinary bolts. (1)



With the advent of ever heavier boltworks at the end of the 1880's, the rise of the automatic bolt motor posed a problem for Sargent & Greenleaf, which had yet to offer a bottom-release time lock as a standard model. To work with the new bolt motors of large vaults and solid safe doors, Sargent introduced the Triple A. Prior to this, Sargent did try custom modifications to some of their earlier existing models to work with bolt motors. Three examples were their Model 2 variant and Model 2A and their modified Model 3A.


A view of the Diebold solid safe door from which this time lock and bolt motor was removed in June 2007.


One dial wheel's obverse side. Each wheel has the case number and a sequential 1, 2, and three; the one with #1 on the lowest number movement #2933 and #3 on movement #2935. Even the dial pointers, second photo, were individually numbered the same way. This indicates that the locks were still at this stage made in batches. Unlike the earlier illustrated movement in example A above, I do not see the movements being individually scratch-marked with corresponding notations on the case interior so it is unknown whether S&G considered the positioning of the timer movements within the lock case to be interchangeable at this time even though it is clear the movements were not yet considered interchangeable between different time locks.

      DSC07050.JPG (614976 bytes)  DSC07051.JPG (593698 bytes) C

An interesting observation is illustrated between these three examples. The case numbers are #46, #423 and #571. Case numbers differ by 377 between example A and B or just over eight times or 820% and 148 between example B and C just over a third or 35%. And yet the movement numbers differ between these examples by over thirteen times or 1372% between A and B and just over 1.5 times or 54% between B and C. What conclusion can be drawn from these statistics? It would appear that the Triple A may have been a somewhat slower seller than other models. Also the simultaneous introductions of the Model A, B and C and the introduction of the four movement Model K and O shortly thereafter caused a huge consumption of L style movements in the first few years of production eventually being the most popular sized movement made by S&G. 

A. Model Triple A, version 1,(later no. 6304), with associated Burton, Harris & Co. bolt motor, 1889. Uses the same sized movements as found in the more common Model Triple B, but in a smaller case; excluding the normal bolt works, hence the smaller size. The lock was designed to sit on top of the separate automatic bolt opener (device below time lock). This is the company's first modular three movement design and this example was one of the first produced. While the design used modular movements they were not yet interchangeable, and each had it's specified location. Interchangeability would not occur until 1895. One can see scratch marks made by the installer on each movement;  I, II, III indicating their order. The snubber bar is of the older design made with separate, welded pieces and the serial numbers of the case and movements indicate that this was a very early in the production. The Burton-Harris type motor was one of the first to be used by S&G. Burton was also one of the first makers of automatic bolt motors beginning in 1884. Early on Burton designed products to be used with the nearby Consolidated Company in Cincinnati, Ohio. However by 1890 Burton developed a closer relationship with Sargent & Greenleaf with Sargent eventually acquiring Burton sometime in 1901. (2)  6 3/4"w x 3 7/8"h x 2 1/2"d. Case# 46, consecutively numbered "L"-size movements #199, #200, #201. This is the earliest known version of this lock. Bolt motor # 331. file 111

One can infer the strength of the spring inside the bolt motor by the length of the key-grip giving leverage to the operator to wind it. The last picture shows the actual Diebold safe door that this lock was removed from. At this time Diebold was a safe manufacturer and had not yet entered the time lock market. See here an identical type Mosler safe door retro-fitted with a later model Mosler time lock. The advantage of bolt motor system is the fact that the bolts do not have to be manually opened through an external crank. As long as the safe was in a secure location, there was also no need for a combination lock. The safe is set to open only when a trusted person is present  This eliminates any holes in the door needed for the bolt crank or combination lock making for a much more secure door. Of course the owner must be sure that he is present when the time lock actuates the bolt motor or else it is open to anyone! The access into the door through these holes for safe crackers must have been a real problem otherwise why would  anyone choose the inconvenience and risk of a safe that opened automatically? See another Burton-Harris bolt motor with a unique Hall time lock.

B. Model Triple A, version 2, early 1890's. Same as above but with some minor differences. The snubber bar is now made of one piece rather than havening the individual dial pin actuators as separate parts welded to the main snubber bar. The bar is also attached to the underlying mount with a sturdier design and attachment to the case. As with example A, this lock was found in complete and original condition and has the company's logo acid etched in the door glass, cork eyelet and cardboard door gaskets. 6 3/4"w x 3 7/8"h x 2 1/2"d. Case #423, consecutively numbered 'L' sized movements #2933, #2944, #29456. file 276

C. Model Triple A., c. mid 1890's. Same as  'B' above but with slightly later scalloped door design. By this time the snubber bar has lost all of the engraved decoration detail. 6 3/4"w x 3 7/8"h x 2 1/2"d. Case # A-571, consecutively numbered "L"-size movements #4525, #4526, #4527.Click here for a rare two movement version of this type of lock and here for another, later version of this lock. file 68

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(1) Sargent & Greenleaf Bank Locks catalog #12, 1907

(2) American Genius Nineteenth Century Bank Locks and Time Locks, David Erroll & John Erroll, pg. 258

(3) American Genius Nineteenth Century Bank Locks and Time Locks, David Erroll & John Erroll, pg. 250-251