Moisture measurement of timber
AssigneeWindsor Engineering Group
InventorMalcolm FREDRIC
Life of this patent
Estimating the term…
Abstract
A kiln moisture measurement method and system is provided for measuring the moisture level of a charge of timber in a timber drying kiln. The method includes steps of: transmitting electromagnetic radiation from a transmitter; receiving the electromagnetic radiation at a receiver; wherein the transmitter and receiver are configured such that the electromagnetic radiation passes through at least part of the charge of timber. An electronic data processor determines the gain of the electromagnetic radiation by comparing the intensities of the transmitted and received electromagnetic radiation; and subsequently determines a moisture level of the charge based on the gain of the electromagnetic radiation.
Claims64
A kiln moisture measurement method for measuring the moisture level of a charge of timber in a timber drying kiln, including steps of:
- transmitting electromagnetic radiation from a transmitter;
- receiving the electromagnetic radiation at a receiver;
- wherein the transmitter and receiver are configured such that the electromagnetic radiation passes through at least part of the charge of timber;
- determining, using an electronic data processor, a property of the electromagnetic radiation by comparing the intensities of the transmitted and received electromagnetic radiation;
- determining a moisture level of the charge based on the determined property of the electromagnetic radiation.
The method of any one of the preceding claims, wherein the electromagnetic radiation has a frequency in the range of 150 MHz to 4 GHz.
The method of any one of the preceding claims, wherein the electromagnetic radiation has a frequency in the VHF or UHF bands, that is, between 150 MHz and 1 GHz.
The method of any one of the preceding claims, wherein the electromagnetic radiation has a frequency in the range of about 280 MHz to 500 MHz.
The method of any one of the preceding claims, wherein the electromagnetic radiation has a frequency in the range of about 290 MHz to about 310 MHz.
The method of any one of the preceding claims wherein the transmitter and receiver are located on opposed side walls of the kiln.
The method of any one of the preceding claims, wherein the transmitter and the receiver are located such that a straight line between the transmitter and receiver is through the charge at a non-perpendicular angle to an incident surface of the charge.
The method of any one of the preceding claims, wherein the distance travelled by the electromagnetic radiation between the transmitter and receiver is greater than the width of the charge.
The method of any one of the preceding claims, wherein the width of the charge is between 1 and 5 meters.
The method of any one of the preceding claims, wherein the distance travelled by the received electromagnetic radiation is between 1 and 7 meters.
The method of any one of the preceding claims, wherein the distance travelled by the received electromagnetic radiation is about 5 meters.
The method of any one of the preceding claims, wherein the charge has a moisture content below its fibre saturation point.
The method of any one of the preceding claims, wherein the charge has a moisture content below about 25%.
The method of any one of the preceding claims, wherein the charge has a moisture content above about 7%.
The method of any one of the preceding claims, further comprising a calibration step including measuring the gain at two different moisture contents and confirming the moisture contents by sampling the charge and oven drying the samples.
The method of any one of the preceding claims comprising determining, using an electronic data processor, the gain of the electromagnetic radiation by comparing the intensities of the transmitted and received electromagnetic radiation;
- and
- determining a moisture level of the charge based on the gain of the electromagnetic radiation.
The method of any one of the preceding claims comprising determining, using an electronic data processor, the phase angle or phase difference of the electromagnetic radiation;
- and
- determining a property of the charge based on the phase angle or phase difference of the electromagnetic radiation.
A kiln moisture measurement system for measuring the moisture content of at least part of a charge of timber in a timber drying kiln comprising at least one timber drying chamber, the system including
- a transmitter of electromagnetic radiation;
- a receiver for receiving the electromagnetic radiation;
- wherein the transmitter and receiver are configured such that the electromagnetic radiation passes through the at least part of the charge of timber;
- a controller comprising an electronic processor configured to determine a property of the electromagnetic radiation by comparing signals indicative of the intensities of the transmitted and received electromagnetic radiation, and further configured to determine a moisture level of the at least part of the charge of timber based on the determined property of the electromagnetic radiation.
The kiln of claim 61 wherein each chamber is configured to deliver different conditions to the or each charge of timber.
Dependencies are inferred from the claim text.