Protective Can And Guidance Pins For The Head; The Mode Study Head Type 4814 - BRUEL & KJAER System V Instruction Manual

The upper radial flexures are attached to the lower surface of the table by a combination
of bolts and high strength adhesive at the outer edge. The lower radial flexures are at­
tached by bolts and high strength adhesive to a stiff platform formed integral with the
skeleton.
The skeleton is machined from a single piece of aluminum . A closely controlled machin­
ing process causes the moving element to have a high resonant frequency and very little
unbalanced mass to cause cross motion problems.
6.1. 9 . Boot
The boot is a rubber diaphragm bonded to the outer skirt of the table and extending out to
the protective can . It prevents dirt and debris from falling into the exciter. A clamping
ring hold s the outer edge of the boot to the protective can .
6.1.10. Protective Can and Guidance Pins for the Head
The protective can for the Head provides a stable base for the Exciter Head when the Ex­
citer Head is not on the Exciter Body. It also protects the driver coil and the moving ele­
ment . Set in the supporting ring of the protective can are three guidance pins, which
serve to line up the Head as it is being placed on the Body and keep the drive coil from
being bumped against the sides of the opening during placement and removal.
6.2. THE M ODE STUDY HEAD TYP E 4814
Fig .6.7 shows an illustration of the Mode Study Head Type 4814 with its rubber boot
and protective can removed.
The construction of the Type 4814 Head is basically the same as that of the previous
three, with the following differences:
1. The Type 4814 is provided with a 19 mm (0 , 75 in) diameter table with one centrally
located mounting point.
~::=::::;;:>"""'~d!~3C:~:&::::;;;;;;~~~;++- ___
Mount i ng point v" ith replacea ble insen
""--k-""'--;~~--
U pp er rad ial fle xure
Mou nting ha les for prOtective can
Fra me
Overtravei stop
Moving elemen t skeleton·rib edge
__________
~
Tangential fle xure
---------- Spl it hub
~~L---------
Dr iver Coil
27' 402
F/g. 6.7. Mode Study Head Type 4814
38