A brief Overview of the technology enabling data transfer in CT machines.

1. SLIP RING
TECNOLOGY

2. BASICS
• The transmission of power across a large free inner
bore is one of the key factors in a rotating system.
• Slip rings are electromechanical devices consisting of
circular electrical conductive rings and brushes that
transmit electrical energy across a moving interface.
• This technology is also called "rotary electrical joint"
and "electric swivel" technology.
• A slip ring can be used in any electromechanical system
that requires unrestrained, intermittent or continuous
rotation while transmitting power and / or data.

3. ORIGINAL REQUIREMENT
• Slip rings were originally designed to carry AC and
DC power from a rotating platform to a stationary
structure, or vice versa.
• Many applications also required, and still require,
the transmission of relatively low bandwidth analog
and digital control signals. In this environment, the
traditional slip ring performs extremely well.
• Modern control systems now also require the
transmission of high bandwidth analog and digital
signals through the slip rings.

4. BASIC DESIGN
• This transmission of power/data is made possible
through electrical connections made by stationary
brushes pressing against rotating circular
conductors.
• The slip-ring design consists of sets of parallel
conductive rings concentric to the gantry axis that
connects to the tube, detectors, and control circuits
by sliding contractors.
• These “sliding contractors” allow the scan frame to
rotate continuously with no need to stop between
rotations to rewind system cables.

6. ARRANGEMENT
• A ring assembly that provides one or more circuit paths. Each
ring is electrically conductive and provides a circuit path over
a full 360° of rotation of the ring assembly.
• Brushes provide electrical contact between the rotating
(usually the ring) and the stationary parts of the assembly.
The brushes ride on the ring, and are mounted in a brush
block assembly, usually on the stationary structure.
• Input and output leads that connect the ring and brushes to
the outside world.
• Connectors that connect to the slip ring assembly wiring.
Connectors are optional, and are often specified by the
customer.

8. • The shiny metal strips carry electric signals that are swept off
by special brushes. The brushes are not in the form of bristles
but rather of metal blocks (in this case a silver alloy).
• The five pairs of larger brushes provide the voltage required
by the x-ray tube, and the three pairs of smaller ones transfer
signals from the gantry controller.
• A slip ring passes electrical power to the rotating components
(e.g., x-ray tube and detectors) without fixed connections.
• The idea is similar to that used by bumper cars; power is
passed to the cars through a metal brush that slides along a
conductive ceiling.
• Similarly, a slip ring is a drum or annulus with grooves along
which electrical contactor brushes slide.

9. • Fiber brush is the term for a particular design of sliding
electrical contacts. Fiber brushes are simply a group of
individual metal fibers (wires) that are collimated by
and terminated into a metal tube.
• In this cantilevered design, the free, unterminated end
of the fiber brush bundle rides in a groove on the ring
surface.
• Brushes are used to transmit electrical power to the
CT scanner components. These brushes glide in
contact grooves along the slip-ring. There are two
types of brushes that can be used; wire and
composite.

10. THANK YOU !!!!!!