Field of the Invention

The present invention relates to the field of traps for rats, and in particular to rat traps for use in sewage systems.

Background of the Invention

A number of traps are known in the art. Types are known using poison for killing rodents and further a number of traps are known that are poison free. The poison free traps generally fall in two categories, these being mechanical traps and electrical traps.

When operating a trap in a sewage system, the trap will normally be fixed in relation to an upstream or downstream sewage pipe or possibly to the sewage well. Such traps fixed in the sewage pipe are subject to corrosive components, in particular when the trap is flooded, e.g. when a high water level occurs in a sewage system. The majority of these components are parts of the mechanical and/or electrical killing device. Furthermore, the particles in the sewage water, such as grease and excrements, tend to clog the parts of the mechanical and/or electrical killing device.

Object of the Invention

The objective of the present invention is to provide a poison free trap that will be less susceptible to corrosion and clogging when flooded.

Description of the Invention

A first aspect relates to a poison free trap for placement in the bottom part of a well in a sewage system, the poison free trap comprising: - a housing; and

- a mechanical and/or electrical killing device positioned within the housing;

wherein the housing comprises:

- a channel with a rat entry opening and a first opening in the upper wall; and - an air trap in air communication with the channel through the first opening in the upper wall, and positioned at a level above the level of the channel;

wherein at least the killing means of the mechanical and/or electrical killing device is positioned within the air trap. Electrical traps are characterised by the killing mechanism being an electrical shock device almost instantly killing the rodent. Mechanical traps are

characterised by killing means that strikes the rodent and almost instantly kills the rodent. The killing means in mechanical traps are normally spring driven or gas pressure driven, and may be recharged by electrical means or gas pressure driven means.

The term "air trap" refers to a structure for separating one compartment filled with air from a compartment filled with a liquid, such as sewage water. In one or more embodiments, the air trap is a chamber with air tight walls.

Preferably, the chamber is sized and configured to hold an air pocket of a size suitable to withstand water reaching the killing means of the mechanical and/or electrical killing device when the well, in which the trap is positioned, is flooded. This is important to avoid clogging or corrosion of the killing means.

Preferably, the chamber is sized and configured to hold an air pocket of a size suitable to withstand water reaching the killing means of the mechanical and/or electrical killing device when positioned at least 4 meters below the water level of a body of water, such as within the range of 4-6 meters, e.g. at least 5 meters below the water level of a body of water, such as within the range of 5-7 meters, e.g. at least 6 meters below the water level of a body of water, such as within the range of 6-8 meters, e.g. at least 7 meters below the water level of a body of water, such as within the range of 7-9 meters.

In one or more embodiments, the air trap is a chamber with air tight walls, and wherein the chamber is sized and configured to hold an air pocket of a size suitable to withstand water reaching the killing means of the mechanical and/or electrical killing device when the poison free trap is positioned at least 4 meters below the water level of a body of water, such as within the range of 4-6 meters, e.g. at least 5 meters below the water level of a body of water, such as within the range of 5-7 meters, e.g. at least 6 meters below the water level of a body of water, such as within the range of 6-8 meters, e.g. at least 7 meters below the water level of a body of water, such as within the range of 7-9 meters.

In one or more embodiments, the air trap is sized and configured to hold an air pocket of a size suitable to withstand water reaching the killing means of the mechanical and/or electrical killing device when the poison free trap is positioned at least 4 meters below the water level of a body of water, such as within the range of 4-6 meters, e.g. at least 5 meters below the water level of a body of water, such as within the range of 5-7 meters, e.g. at least 6 meters below the water level of a body of water, such as within the range of 6-8 meters, e.g. at least 7 meters below the water level of a body of water, such as within the range of 7-9 meters.

In one or more embodiments, the air trap is sized and configured to hold an air pocket of a size suitable to withstand water reaching the mechanical and/or electrical killing device when the channel is flooded.

In one or more embodiments, the poison free trap further comprises means adapted for positioning the rat entry opening in front of the mouth of a side branch pipe in the well. The means may in one or more embodiments comprise an upper member having a shape corresponding to an upper part of the cross section of the branch pipe. In one or more embodiments, the lower member is pivotally connected to the upper member. Preferably, the lower member is adapted only to pivot in front of the housing, such that a rat approaching the front of the trap is unable to push it. When sewage water enters the side branch pipe from behind the housing, the lower member is able to rise, thereby allowing the sewage water to pass unhindered. In one or more embodiments, a bridge member is positioned above the lower member to enable an easier passage for an incoming rat into the channel through the rat entry opening.

In one or more embodiments, a) the means for positioning the rat entry opening in front of the mouth of a side branch pipe in the well and/or the front of the housing is configured such that the channel will incline at an angle of within 10- 30 degrees relative to the side branch pipe when the poison free trap is mounted thereto. This angle is important, as the killed rat is thereby able to fall out of the channel, and will be washed away with the flowing sewage water. In one or more embodiments, the channel will incline at an angle of within 10-30 degrees relative to the side branch pipe, such as within 12-28 degrees, e.g. within 14-26 degrees, such as within 1 6-24 degrees, e.g. within 18-22 degrees, when the poison free trap is mounted thereto. In one or more embodiments, the housing is configured such that the channel will incline at an angle of within 10-30 degrees relative to the side branch pipe when the poison free trap is mounted thereto. In one or more embodiments, the channel will incline at an angle of within 10-30 degrees relative to the side branch pipe, such as within 12-28 degrees, e.g. within 14-26 degrees, such as within 1 6-24 degrees, e.g. within 18-22 degrees, when the poison free trap is mounted thereto.

In one or more embodiments, the front wall of the housing has a rearward inclination angle of within 10-30 degrees. In one or more embodiments, the housing has a rearward inclination angle of within 10-30 degrees, such as within 12-28 degrees, e.g. within 14-26 degrees, such as within 1 6-24 degrees, e.g. within 18-22 degrees.

In one or more embodiments, the housing further comprises means for releasably attaching a mounting pole. The poison free trap may be mounted to the side branch pipe with a method as disclosed in EP2685015, hereby incorporated by reference.

In one or more embodiments, the housing further comprises means for releasably attaching a mounting pole, the means comprising a plurality of attachment points positioned along the length of the housing. This will allow the operator to tilt the poison free trap during the mounting operation.

In one or more embodiments, the channel and the air trap are releasably fastened to one another. This configuration is advantageous for maintenance of the mechanical and/or electrical killing device.

In one or more embodiments, a window is positioned in a closed end of the channel, which makes the channel appear as an open-ended channel. This configuration allows the rat to see through the tunnel to the other side of the trap, whereby it will not hesitate to enter the trap.

In one or more embodiments, a pressure sensor is positioned within the air trap. A signal indicating the pressure within the air trap may, in one or more

embodiments, be transmitted (by the pressure sensor or a separate signaling means) wirelessly to a receiving device located at top of the sewage system enabling SMS communication to a computer or other devices.

A second aspect relates to a poison free trap for placement in the bottom part of a well in a sewage system, the poison free trap comprising: - a housing; and

- a mechanical and/or electrical killing device positioned within the housing (200); wherein the housing comprises:

- a channel with a rat entry opening and a first opening in the upper wall;

wherein mechanical and/or electrical killing device is positioned above the first opening in the upper wall;

wherein the front wall of the housing has a rearward inclination angle of within 10-30 degrees. A third aspect relates to a poison free trap for placement in the bottom part of a well in a sewage system, the poison free trap comprising:

- a housing; and

- a mechanical and/or electrical killing device positioned within the housing;

wherein the housing comprises:

- a channel with a rat entry opening and a first opening in the upper wall;

wherein mechanical and/or electrical killing device is positioned above the first opening in the upper wall;

wherein the housing is configured such that the channel will incline at an angle of within 10-30 degrees relative to the side branch pipe when the poison free trap is mounted thereto.

A fourth aspect relates to a poison free trap for placement in the bottom part of a well in a sewage system, the poison free trap comprising:

- a housing;

- a mechanical and/or electrical killing device positioned within the housing (200); and

- means adapted for positioning the rat entry opening in front of the mouth of a side branch pipe in the well;

wherein the housing comprises:

- a channel with a rat entry opening and a first opening in the upper wall;

wherein mechanical and/or electrical killing device is positioned above the first opening in the upper wall;

wherein a) the means for positioning the rat entry opening in front of the mouth of a side branch pipe in the well and/or b) the front of the housing is configured such that the channel will incline at an angle of within 10-30 degrees relative to the side branch pipe when the poison free trap is mounted thereto.

Advantageously the killing device is a gas cartridge operated device. Such device has shown to be appropriate for such installation. Other types of killing devices may however also be used without limiting the scope of the invention. The gas cartridge operated device, as well as other non-electrical devices, has the advantage of being usable in APEX areas without the risk of igniting gas or flammable fluid.

Advantageously a signal indicating the activation of the killing device is

transmitted wirelessly to a receiving device. Hereby electrical connections, e.g. cable connections, between the killing device and a communication device, placed at a distance from the killing device, may be avoided. The communication device eventually has a radio module enabling the device to send SMS

messages to a computer.

The walls defining the channel is preferably configured with smooth surfaces to avoid gnaw damage.

As used in the specification and the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from "about" or "approximately" one particular value and/or to "about" or "approximately" another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about", it will be understood that the particular value forms another embodiment. It should be noted that embodiments and features described in the context of one of the aspects of the present invention also apply to the other aspects of the invention.

The invention is described in more detail in the following detailed description of a preferred embodiment, with reference to the figures.

Brief description of the figures

Figure 1 is a perspective view of a poison free rat trap in accordance with various embodiments of the invention;

Figure 2 is a side view of a poison free rat and/or mouse trap in accordance with various embodiments of the invention, where it is mounted to a side branch pipe in a well;

Figure 3 is a front view of a poison free rat trap in accordance with various embodiments of the invention;

Figure 4 is an exploded view of a poison free rat trap in accordance with various embodiments of the invention; and

Figure 5 is a back view of a poison free rat trap in accordance with various embodiments of the invention. References

10 Well

12 Side branch pipe

14 Angle

100 Poison free rat trap

200 Housing

210 Channel

212 Rat entry opening

214 First opening

21 6 Upper wall

218 Window

220 Air trap

230 Front wall

240 Means for releasably attaching a mounting pole

242 Attachment point

300 Mechanical and/or electrical killing device

310 Killing means

400 Means for positioning the rat entry opening in front of the mouth of a side branch pipe in the well

410 Upper member

420 Lower member

430 Bridge member

500 Helical spring positioned within a tubing

Detailed Description of the Invention

Figure 1 shows a perspective view of a poison free trap according to the invention. The poison free trap 100 is adapted for placement in the bottom part of a well 10 (Figure 2) in a sewage system. The poison free trap 100 comprises a housing 200, and a mechanical and/or electrical killing device 300 (Figure 4) positioned within the housing 200.

The housing 200 comprises a channel 210 with a rat entry opening 212 (Figures 3+4) and a first opening 214 (Figure 4) in the upper wall 21 6 (Figure 4); and an air trap 220 in air communication with the channel 210 through the first opening 214 in the upper wall 21 6, and positioned at a level above the level of the channel 210. The air trap 220 is a chamber with air tight walls, and is sized and configured to hold an air pocket of a size suitable to withstand water reaching the mechanical and/or electrical killing device 300 when the well 10 is flooded.

The mechanical and/or electrical killing device 300 (Figure 4) is positioned within the air trap 220. The poison free trap 100 further comprises means 400 adapted for positioning the rat entry opening 212 in front of the mouth of a side branch pipe 12 in the well 10 (Figure 2). The means 400 comprises an upper member 410 having a shape corresponding to an upper part of the cross section of the branch pipe 12. The lower member 420 is pivotally connected to the upper member 410.

Preferably, the lower member 420 is adapted to only to move in front of the housing 200, such that a rat approaching the front of the trap is unable to move it. When sewage water enters the side branch pipe 12 from behind the housing 200, the lower member 420 is able to rise, thereby allowing the sewage water to pass unhindered. A bridge member 430 (Figure 1 ) is positioned above the lower member 420 to enable an easier passage for an incoming rat into the channel

210 through the rat entry opening 212.

The means 400 for positioning the rat entry opening 212 in front of the mouth of a side branch pipe 12 in the well 10, and the front wall 230 of the housing 200 is configured such that the channel 210 will incline at an angle 14 of within 10-30 degrees relative to the side branch pipe 12 when the poison free trap 100 is mounted thereto.

The poison free trap 100 is mounted to the side branch pipe 12 with a method as disclosed in EP2685015, hereby incorporated by reference. In short, the method comprises the following steps:

a) determining the dimension of the side branch pipe, and selecting the means for positioning the rat entry opening in front of the mouth of the side branch pipe having the appropriate corresponding outer dimension;

b) releasably attaching the poison free trap to a mounting pole;

c) attaching a flexible member to the poison free trap;

d) lowering the poison free trap down the well by means of the pole, and keeping an end of the flexible member above the well;

e) inserting the means for positioning the rat entry opening in front of the mouth of the side branch pipe into the side branch pipe by means of the pole;

f) tightening the flexible member along the inner wall and above the branch pipe of the well, providing a substantially vertical upwards force on the poison free trap, thereby fixing the means for positioning the rat entry opening in front of the mouth of the side branch pipe against an upper part of the side branch pipe; g) fixating the flexible member inside the well ;

h) releasing the mounting pole from the poison free trap, and withdrawing the mounting pole from the well.

The flexible member may be simply a rope with an inherent flexible

characteristic, or the rope or wire, where it is engaged with the poison free trap, may be provided with a spring, for example a helical spring 500 (Figure 1 , positioned within a tubing), such that the spring force is determining the force by which the means for positioning the rat entry opening in front of the mouth of the side branch pipe is urged against the upper section of the branch pipe. The housing 200 is shown comprising means 240 for releasably attaching a mounting pole. The means 240 comprises a plurality of attachment points 242 positioned along the length of the housing 200 (Figure 2).

The channel 210 and the air trap 220 are releasably fastened to one another, as seen in Figure 4. The killing device is here shown as a gas cartridge operated device, where a killing piston is provided inside the killing device housing. Upon triggering of a trigger mechanism present in the cavity, the killing piston will propagate through the first opening 214 and into the channel 210; and with a significant force, hit the rat that has activated the trigger mechanism. Other types of traps or killing devices may however also be used.

Figure 5 is a back view of a poison free rat trap in accordance with various embodiments of the invention. A window 218 is positioned in the closed end of the channel 210, which makes the channel appear as an open-ended channel. This configuration allows the rat to see through the tunnel to the other side of the trap, whereby it will not hesitate to enter the trap.