Automatic Rotor Assembly Line

a complex of power tools, conveyers, and instruments combined into a single automatic control system in which the workpieces are both machined and shifted around the arcs of circles simultaneously with the tools that are working on them. Automatic rotor assembly lines are most commonly used for operations performed by a straight-line operating movement (stamping, drawing, punching, assembling, and inspecting).

An automatic rotor assembly line consists of working rotors and conveyer rotors that transfer the workpieces from one working rotor to another. A working rotor is a rigid system on which a group of tools is mounted, equally positioned around the common rotating shaft of the system. The necessary operating movements are transmitted to these tools by actuating members: mechanical members for low forces and hydraulic members for high forces (for example, piston rods of hydraulic power cylinders). A tool is usually mounted complete in preadjusted units (apart from power tools) and is connected with the actuating members of the rotor mainly by a simple axial coupling, so the units may be replaced quickly. The conveyer rotors accept, transport, and pass on the workpieces. These rotors are drums or disks equipped with carrier members. Frequently used are simple conveyer rotors which have the same conveyer speed, a common conveying plane, and the same orientation as the objects being machined. In order to pass workpieces between working rotors with different step distances or different positions for the objects being machined, conveyer rotors that vary their angular speed and the position of the transported objects have been designed. The working and conveying rotors are combined in a line with a common synchronous drive that moves every rotor one step at a time in accord with the rate for the line.

An automatic rotor assembly line is able to perform operations that differ considerably in duration, such as thermal, chemical, punching, and inspecting operations. An automatic rotor assembly line can process several different work-pieces simultaneously. Such composite automatic rotor assembly lines can be used for small-run productions.

An automatic rotor assembly line can be operated by means of so-called cyclic graphs, which ensure that every member is actuated by the main control in accord with one of the several principles provided (for example, to perform a processing run or to abandon it). Such automatic rotor assembly lines allow a machine to respond without stopping for departures from the normal course of operation, such as the arrival of a substandard object, a feed cutoff of parts during assembly, and so on.

Automatic rotor assembly lines were built in the USSR during the late 1930’s and abroad in the early 1950’s. They found application in the USSR in cold-punching production, in the food industries (packaging and packing liquid products), and in the manufacture of plastic piece parts. The future spread of automatic rotor assembly lines for mass production items (radio parts, punched parts, and others) is especially promising. They are most effectively used in production where the manufacturing sequence is short and for the fabrication of relatively simple objects which have the form of a solid of revolution.

The productivity of an automatic rotor assembly line is controlled by the conveyer rotor speed and the step distance between workpieces in a rotor. Compared to separate automata not of the rotor type, the use of an automatic rotor assembly line reduces the production cycle by a factor of 10 to 15; the in-process stock of semifinished pieces is greatly reduced (by a factor of 20 to 25), manufacturing area is freed, the labor cost and production cost are reduced by several times, and capital expenditures are paid for in one to three years.