User's Manual

Exhibit 9

US7,420,471; US8,169,335; US8,232,888; US5,939,986;

US6,810,353; AU2005289704; ZA2007/02919; ZA2008/02673;

ZA2010/06816, ZA2010/09068 Patent Pending

1 Overview

The Field Sense Cab Silencer, model # 1309890, is part of a complete iWAREHOUSE Field Sense

System. This device, designed by Frederick Energy Products, installs on lift trucks and creates a

pulsing 73 kHz magnetic field. The 73 kHz magnetic field has unique characteristics that a

Personal Alarm Device (PAD) detects and recognizes as a signal to ignore standard 73 kHz

magnetic fields emitted from iWAREHOUSE Magnetic Field Generators (MFGs). The Cab

Silencer is typically installed within the crew cab of a fork truck to silence the truck operators

PAD from sounding alarms to magnetic fields from other trucks with MFGs, while the operator

is inside the cab. The size of the magnetic field is adjusted such that the field covers the cab

volume but does not extend outside the cab. Thus, the operator’s PAD is deactivated inside the

cab but is reactivated when the operator leaves the cab.

Optional functional uses for Cab Silencer units allow the magnetic field pulses from the Cab

Silencer to be slightly altered by switch settings on the Cab Silencer printed circuit board. The

Cab Silencer can also be used as an “Aisle Identifier” or “Roadway Marker”, where the unit is

installed at select locations on facility storage racks. With a proper switch setting, the Cab

Silencer unit will emit altered magnetic field pulses that Collision Avoidance Modules (CAMs)

can interpret to identify specific types of locations. PADs are not affected by units used as Aisle

Identifier or Roadway Marker.

1.1 Theory of Operation

The function of the Cab Silencer is:

• To transmit a 73 kHz magnetic field around a fork truck operator’s crew cab to act as a

silent zone for PADS worn by the operator while operating the truck.

• In an alternate setting, to transmit variations in the magnetic field pulses that CAMs can

detect as location markers.

The Cab Silencer has an internal 73 kHz transmitter and an inductor that creates a pulsed

magnetic field around the Cab Silencer. When the unit is mounted on a lift truck, the magnetic

field serves as a silent zone in the operator’s cab of the truck. In some cases, an EMI

background within the operator’s crew cab is strong enough to interfere with the operator’s

PAD detecting/interpreting the Cab Silencer magnetic field. For this case, an internal switch on

the printed circuit can be activated to cause the Cab Silencer to emit a more robust silencing

field to counteract the EMI interference. Using this setting, however, can result in the

performance of the Collision Avoidance Module (CAM) on the truck being affected by the Cab

Silencer field if the Cab Silencer is too close to the CAM. To prevent interference with the CAM,

the Cab Silencer needs to be located at least 5 feet away from the MFG/CAM.

When mounted on a facility structure, with proper switch selection, the unit’s magnetic field

can be set to identify Aisle Identifier or Roadway Marker locations in the facility. When a CAM