NZ333116A - Protecting crops from frost damage by blowing air around crops from perforated tubes - Google Patents

Abstract

A frost protection system for crops or plants uses air blown through perforated pipes 16. The air creates turbulence around the plants to reduce frost damage. The air may be heated. The pipes are the same as those used for irrigation. A valve 10 isolates the pipes form a water supply when a blower 12 is running. The blower is protected from irrigation water by valve 14.

Description

67405 • 10 PATENTS FORM 5 PATENTS ACT 1953 COMPLETE SPECIFICATION Number 333116 Dated 1 June 1999 METHOD AND SYSTEM FOR PROTECTING CROPS FROM FROST DAMAGE We, NEIL CRAWFORD PETRIE, a British citizen, of Sulphur Wells, RD 11, Masterton, New Zealand and DENNIS JAMES ORDISH, a New Zealand citizen, of 19A Cole Street, Masterton, New Zealand, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement.

PSSB^SrvoFFl5| 1 I 1 JU:j 2000 I FIELD OF INVENTION The invention comprises a method and system for protecting crops from frost damage.

SUMMARY OF INVENTION In broad terms in one aspect the invention comprises a method of irrigating crop plants and protecting the plants from frost damage comprising positioning at least one pipe along or between one or more rows of crop plants, the pipe(s) comprising a number of outlets along 10 the length of the pipe(s), periodically connecting the pipe(s) to a supply of water under pressure to irrigate the plants, and disconnecting the pipe(s) from the water supply and connecting the pipe(s) to a flow of air to blow air through the pipe(s) and from the outlets to create air turbulence around the plants when the air temperature falls such that there is a risk of frost damage.

In broad terms in another aspect the invention comprises an irrigation and frost protection system an irrigation and frost protection system for crops, comprising at least one pipe positioned along or between one or more rows of crop plants and comprising a number of outlets along the pipe(s), a pump or supply of water under pressure, valve means for 20 connecting and disconnecting the pump or water supply to and from the pipe(s), and at least one blower and valve means for connecting the blower(s) to the pipe(s) to blow a flow of air through the pipe(s) to create air turbulence around the plants for frost protection.

BRIEF DESCRIPTION OF THE DRAWINGS Preferred forms of the invention will now be described with reference to the accompanying drawings in which: ' 8 DEC 2001 Received 67405 Fig. 1 is a schematic plan diagram of a frost protection system of the invention, and I Fig. 2 is a drawing showing the frost protection system of the invention in use. 5 DETAILED DESCRIPTION OF PREFERRED FORM I The frost protection system is generally shown in a preferred form in Fig 1 connected to an existing irrigation system for crop plants such as fruit trees, vines, or vegetable plants. The irrigation system comprises a series of irrigation pipes 2 10 positioned between rows of plants such as fruit trees 3 shown in Fig 2. Each pipe 2 is connected to one of a number of sub-mains 4. Each sub-main 4 is connected to a main line 6. During the irrigation water under pressure is supplied to main line 6 via a pump or from the water mains. Water exits from the pipes 2 through outlets spaced along each pipe, which typically comprise nozzles or similar which produce a I spray of water on the foliage and/or fruit or on the ground above the root structures of the crops. It is common for crops to be divided into irrigation blocks, for example irrigation block 8 in. Fig 1. The flow of water into irrigation block 8 may be controlled by a valve 10 or similar. This permits selected blocks to be irrigated and allows successive blocks to be irrigated periodically.

| In the method of the;invention the irrigation pipes are also used to protect the crops i from frost. A blower 12 is also connected to sub-main 4. A solenoid or other valve l 14 between the blower 12 and the sub-main 4 protects the blower 12 from water I damage. The blower 12 may comprise any known device for delivering air under pressure into the irrigation pipes including a ducted fan, ventilating fan, or rotary i compressor. j j i l In operation of the system in frost protection mode, typically late at night or in the early morning, the water supply is first shut off either at the water source or at 30 valves 10 The blower 12 is operated to pump air to pipes 2. As shown in Fig 2, air is blown from outlets 16 spaced along each pipe creating air turbulence around the crops. 3 67405 Blowing air into each block successively is not preferred for frost protection as frost may very quickly damage entire blocks. For adequate frost protection it is preferred to connect more than one blower to the irrigation network, as shown in Fig 1 in which a further blower 12A is used. By selecting appropriate sizes and positions for 5 each blower, air may be blown to all blocks in the irrigation network simultaneously.

Preferably the air is heated or warmed before being blown through the pipe network. The blower(s) may include heating elements which heat the air stream from each blower. Alternatively the blower(s) may compress air which will heat the air.

The blowers may be manually started. Alternatively they may be automatically started by thermostats (not shown) arranged to detect a threshold temperature below which frost damage may occur to the crops. It will be appreciated that where thermostats are used, the thermostats may be interfaced to the valves to select 15 between irrigation and frost protection functions. For example, once the temperature has dropped below a pre-determined value, valve 10 is closed to prevent water from entering the pipes 2, valve 14 is opened, and blower 12 is activated to protect block 8 from frost. Once the temperature has reached an acceptable level, blower 12 is turned off, valve 14 is closed, and valve 10 is opened 20 to resume normal irrigation.

Fungicides, insecticides and bird-repellent may be applied to the crops by introducing these chemicals into the air stream from each blower. It will be appreciated that the application of chemicals in this way provides a useful choice 25 over existing tractor-based methods.

The invention is described above with reference to the use of irrigation pipes but alternatively dedicated pipes used only for frost protection purposes may be laid in the orchid or vineyard or similar. In this case the blower(s) may be permanently 30 connected to the pipe network and operation of the blower(s) controlled by a thermostat-based electronic control system. 4 67405 The foregoing describes the invention including preferred forms thereof. Alterations and modifications, as will be obvious to those skilled in the art, are intended to be incorporated within the scope thereof as defined in the following claims.

Claims (8)

CLAIMS „ „ „ $ 10

1. A method of irrigating crop plants and protecting the plants from frost damage comprising positioning at least one pipe along or between one or more rows of crop plants, the pipe(s) comprising a number of outlets along the length of the pipe(s), periodically connecting the pipe(s) to a supply of water under pressure to irrigate the plants, and disconnecting the pipe(s) from the water supply and connecting the pipe(s) to a flow of air to blow air through the pipe(s) and from the outlets to create air turbulence around the plants when the air temperature falls such that there is a risk of frost damage.

2. A method according to claim 1 including heating or warming the air blown through the pipe(s).

3. An irrigation and frost protection system for crops, comprising at least one pipe 15 positioned along or between one or more rows of crop plants and comprising a number of outlets along the pipe(s), a pump or supply of water under pressure, valve means for connecting and disconnecting the pump or water supply to and from the pipe(s), and at least one blower and valve means for connecting the blower(s) to the pipe(s) to blow a flow of air through the pipe(s) to create air turbulence around the plants for frost protection. 20 25

4. A system according to claim 3 including a thermostat-based control system arranged to detect the ambient air temperature and operate the blower(s) to blow air through the pipe(s) when the air temperature falls to a threshold temperature below which frost damage may occur to the plants.

5. A system according to claim 4 wherein the thermostat-based control system is arranged to operate one or more valves to connect the blower(s) to the pipe(s) as well as starting the blowers on detecting a fall in air temperature to the threshold temperature. 30 6. A frost protection system according to any one of claims 3 to 5 including means associated with the blower(s) to heat or warm the air.

6 intellectual property office of n.z. 1 8 DEC 2001 receiveo

7. A method for protecting crops from frost damage according to claim 1 and substantially as herein described with reference to the accompanying drawings.

8. A frost protection system for crops according to claim 3 and substantially as herein described with reference to the accompanying drawings. END OF CLAIMS 7 intellectual property office of nz. 1 8 DEC 2001 RECEIVED