| GENE SLOVER'S US NAVY PAGES NAVAL ORDNANCE AND GUNNERY, VOLUME 1 CHAPTER 10 AUTOMATIC CONTROL EQUIPMENT |
| HOME INDEX Chapter 10 Automatic Control Equipment A. Introduction B. Synchros C. Electric-hydraulic systems D. Amplidyne follow-up system E. Other types F. Shipboard tests of automatic control equipment |
| A. Introduction 10A1. General Automatic control equipment, also referred to as remote-control power-drive equipment, is provided to position the various elements of the battery in correspondence with an electrical order, called the signal, received from some other station, generally a computer. The elements commonly using this equipment are turrets, mounts, and directors. The advantages of automatic control equipment are the speed and accuracy with which guns may be laid and fired. The training and elevating of guns by manual control of power equipment, either by matching indicating dials or by using telescopes, is relatively difficult and inaccurate. Fluctuations in the incoming gun order, the inertia of heavy turrets or mounts, rolling and pitching of the gun platform, and the personal reaction time of the pointers and trainers in observing and responding to a variation in the order- all these tend to cause inaccuracy in the gun laying, with resulting large patterns. The design of automatic control equipment depends upon the nature and source of the signal, the load to be moved, and the nature of the damping required to eliminate random movements and to ensure accuracy and rapidity of response. The principle of automatic control is applied in ordnance equipment both where loads are light (as in computers and indicators) and where they are heavy (as in driving gun mounts, turrets, or fire control directors). Light loads are usually driven by small electric motors. For heavy loads, either of two general types of power drive is used: (1) electric-hydraulic or (2) amplidyne. Electric-hydraulic drives are powerful, reliable, and accurate. They are used principally where loads are heavy, as in the training and elevating gear of mounts and turrets, or when large starting and stopping forces are involved, as on ammunition hoists and rammer mechanisms. Their principal disadvantage is the constant maintenance effort required. Amplidyne drives are also reliable and accurate, and require less maintenance. They are superior to electric-hydraulic drives for lighter loads and are used on mounts, directors, and searchlights. To date, the largest size in use is the train unit on the 5”/54 Single Mount Mark 39. 10A2. The basic problem The basic technical problem incurred in driving a mount or director in response to a remote signal is divided into four general phases, as illustrated in figure 10A1. 1. An order signal is received from a remote station. It is compared with the response or position of the load (mount). The result of this comparison is an error signal. 2. The error signal is amplified to operate the controls of the power drive unit. 3. The power drive unit drives the load in such a manner as to reduce the error signal to zero. 4. In the driving of the load a response is sent back to be compared with the order signal. |
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