Emerson DCX S, Руководство по эксплуатации

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88 100-412-183 REV. 13
6.1.1 Component Functional Description
Ultrasonic Stack
Converter
The converter is mounted in the customer's automation as part of the ultrasonic stack. The
ultrasonic electrical energy from the power supply is applied to the converter (sometimes
called the transducer). This transforms the high frequency electrical oscillations into
mechanical vibrations at the same frequency as the electrical oscillations. The heart of the
converter are piezoelectric ceramic elements. When subjected to an alternating voltage, these
elements alternately expand and contract, resulting in better than 90% conversion of electrical
to mechanical energy.
Booster
It is important to be able to modify the horn face amplitude for successful ultrasonic assembly.
The booster provides a means to modify the amplitude. It is designed to couple different ratios
of ultrasonic energy to the horn, which will in turn increase or decrease the amplitude at the
face of the horn. This is accomplished by varying the ratios of the masses of the input and
output half sections of the booster.
The booster is a resonant half-wave section of aluminum or titanium. It is mounted between
the converter and the horn, as part of the ultrasonic stack. It also provides a clamping point for
rigid stack mounting.
Horn
The horn is selected or designed for a specific application. Each horn is tuned typically as a
half-wave section that applies the necessary force and vibration uniformly to the parts to be
assembled. It transfers ultrasonic vibrations from the converter to the workpiece. The horn is
mounted to the booster as part of the ultrasonic stack.
Depending on their profile, horns are referred to as stepped, conical, exponential, bar, or
catenoidal. The shape of the horn determines the amplitude at the face of the horn. Depending
on the application, horns can be made from titanium alloys, aluminum, or steel. Titanium
alloys are the best materials for horn fabrication due to their high level of strength and low
loss. Aluminum horns are usually chrome- or nickel-plated or hard-coated to reduce wear.
Steel horns are for low amplitude requiring hardness, such as ultrasonic insertion applications.
Solid Mount Boosters
The solid mount booster is a one-half wave-length resonant section made exclusively of
titanium. It is mounted between the converter and the horn, modifying the amplitude of
vibration applied to the horn and providing a clamping point.
The solid mount booster is superior to prior versions in that deflection is minimized. This is the
result of a redesigned clamp-ring which employs a metal-to-metal press fit rather than an O-
ring assembly.
The advantage this booster offers is its improved rigidity. For continuous applications, this
means more energy delivered to the product, while in plunge applications, improved alignment
is possible. The solid mount provides improved positional alignment and will benefit continuous
applications where high force, high side load, or high cycle rates are necessary. In plunge
welding applications, overall deflection is reduced by an average of 0.0025 in. (0.064 mm)
over a wide variety of materials, joint designs, and operating conditions. The results of this
testing in combination with information drawn from field testing indicate that the solid mount
will benefit plunge applications where precision alignment is necessary (such as staking,
swaging, or insertion) or where concentricity/parallelism is critical.