GB2491633A

GB2491633A - Apparatus to prevent the free movement of rats inside sewer /drainage pipes

Info

Publication number: GB2491633A
Application number: GB1109700.3A
Authority: GB
Inventors: Declan Martin Melia
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-06-10
Filing date: 2011-06-10
Publication date: 2012-12-12
Anticipated expiration: 2031-06-10
Also published as: GB201109700D0; GB2491633B

Abstract

The present invention relates to a device placed inside a sewer pipe to prevent the free movement of rats. The device comprises a curved pipe shaped body 1 attached to a curved hinged flap 2 via a hinge (4 figure 2). This will allow the unimpeded flow of liquid & solid waste downstream (10 figure 5) inside the pipe but at the same time prevent the movement of rats upstream. Attached is a nut, 3 to allow the installation of the device into a deep, or a shallow pipe system by means of an insertion tool. The device is held in position inside the sewer pipe by the natural spring action of the frame exerting against the inside of the pipe so as to form a friction fit.

Description

Apparatus to prevent the free movement of rats inside sewer /drainage pipes.

Field of invention

The apparatus relates to the problem of rats colonising communal sewer and drainage pipes, in particular pipes servicing dwellings and commerical buildings.

Background

Presently a large percentage of the rat population lives in the sewer system. They can and do move freely upstream from the main sewer pipes into the sewer pipes servicing any dwelling or commerical premesis.

It has up until now been difficult to both allow the unimpeded flow of waste solids and liguids downstream inside the sewer pipe and at the same time prevent rat movement upstream through the sewer pipes.

By their nature rats gnaw and burrow vigoursly and given an opportunity they attack any weakness in the connections of the sewer pipes thus allowing them to get out of the pipes and into the surronding soil to nest.

As the pipes are usually laid quite close to the building they serve, this can and does allow the rats to enter and nest in the cavity walls of the building, occasionally emerging into the building proper, this is usually completed out of sight under the pathway surronding the building.

Statement of invention

The device comprises of a shaped body, that fits tightly inside the sewer pipe. A movable concave flap is connected to the top of said body by way of a hinge to the top edge of the flap allowing for a swinging action. A threaded nut is secured to the top of the body.

The advantages of the device are that no hardware or fasteners are used during installation to secure the said device in place rather it is held in place by the force exerted to the inside of the pipe by the natural spring action of the device body, this is an important feature as due to pipe inaccessability it would not be practicable to secure the device in situe using fasteners.

The sewer rat or Rattus Norvegicus, as a species has a average weight of 500grams and cannot exert enough force onto the device to dislodge it from its position once installed. A key feature of the device is that it can be installed into a pipe beyond arms reach using the attached nut (3) on top of the device body by lowering the device into position using a seperate tool In one embodiment the hinged flap is curved and opens fully from its normally relaxed perpendicular position to allow virtually the full internal volume of the pipe to be available for waste flow.

The curved shape of said flap (2) when it is in this perpendicular position prevents the movement of rats upstream.

An object of the invention is that again because of the curved shape rats will be unable to gnaw the device as no edges or corners are presented to them.

Brief description of the drawings:

Fig 1 & la show an isometric view of the device according to the invention.

Fig 2, 2b, 2d & 2e show the flap in different planes with fig 2a & 2c showing the hinge pin in both isometric and side view.

Fig3, 3a, 3b & 3c showing isometric, front, side and bottom of body.

Fig 4 shows completed assembly of device from bottom and fig4a from the top view.

Fig5 shows the device installed in a sewer. Fig 5a illustrates how a rat connot pass upstream through the unit.

Fig6 shows a front view while installed in sewer.

Detailed description of the drawings

Referring to the drawings starting with Fig 1 and la, an isometric view of the finished assembly prior to installation into the chamber, with the pipe shaped body (1) the flap hanging in the perpendicular position (2) Fig la has flap (2) shown in the fully open position allowing the passage of waste through the device, this view shows the attached nut (3) Fig 2 for clarity illustrates the isometric view of the unassembled flap (2) with fig 2c, a side view showing the hinge pin (4) Fig 2b top view, fig 2d front view and fig 2e side view show the flap (2) with the required curvature to both fill the void inside the pipe when in the closed position but at the same time the said shape prevents the flap from moving back against the flow of waste thus preventing rats from walking upstream inside the pipe.

Fig 3, gives an isometric view illustrating the pipe shaped body assembly (1) with attached nut (3) . Fig 3a gives a front view of the unassembled body (1) Fig 3 b gives the view of the side of the body (1) Fig 3c illustrates the bottom view of the body (1) Fig 4 refers to the bottom view of the completled assembly with the hinge pin (4) shown also fig 4a shows the top view of the device with the attached nut (3) Fig 5 illustrates the device completley installed in the sewer system in the closed position, in this mode liquid waste (10) can flow downstream through the unit even without fully activating the hinged flap, increased movement of the flap is only necessary when solid waste begins to push lightly against it.

Fig 5a illustrates how a rat cannot pass upstream through the device.

Fig 6 illustrates the secure fit that the body (1) makes against the inside of the pipe (6) with liquid waste (10) flowing along the bottom of the pipe, this drawing illustrates the gap between the said body (1) and the flap (2) to allow free movement of the said flap.

Claims

Claims 1. Apparatus to prevent the free movement of rats inside sewer / drainage pipes comprising: a convex shaped frame (1) to fit tightly inside a pipe (6) using the natural spring action exerted by the shape of the metal frame against the inside of a sewer pipe (6) to fix it in place without the use of hardware/fasteners; a movable flap (2) that normally hangs perpendicular by means of a single hinge pin (4) that will allow the passage of waste downstream; a nut (3) attached to the top of the device body (1) to provide or the attachment of a threaded insertion tool where the device will be installed inside a deep inspection chamber; both frame and flap shaped in a way so as to prevent the flap swing past perpendicular in opposite direction (2) which as a result prevents rat movement upstream.
2. Apparatus to prevent the free movement of rats inside sewer / drainage pipes as claimed in claim 1: wherein the hinged movable flap (2) by way of its convex shape fits flush with the inside of the pipe when in the open position so as to provide as much of the internal volume of the pipe as is possible for the efficient flow of waste.
3. Apparatus to prevent the free movement of rats inside sewer / drainage pipes as claimed in claim 1: where the hinged movable flap (2) falls back into perpendicular position as a result of gravity, instantly after the passage of waste through the device.