BIRD DRINKING TROUGH

Abstract: In winter, birds in the open can suffer when cold weather causes the usual water supplies to freeze. Although householders put out extra water this also becomes quickly frozen. The invention provides a drinking trough using thermal insulation to delay freezing. A drinking trough comprises a thermally insulated water bowl (1) containing a float (3), the float being capable of covering substantially the whole surface area of a body of water (2) in the bowl, and the float having a drinking hole (7) that exposes only a minimal area of the water surface. A wind vane (4) carried on the float (3) allows wind gusts to agitate the water surface and thus further delay freezing.

Description: BIRD DRINKING TROUGH This invention relates to a bird drinking trough. In the winter, wild birds as well as those in open air aviaries can suffer hardship due to a lack of drinking water when the cold weather has caused ice to form on the available water deposits. A prolonged cold spell can cause bird deaths because any exposed surface of water will freeze quickly and birds must have a continuous supply of drinking water to prevent dehydration. It is also believed that water may be necessary to birds for preening, bodily and metabolic reasons. A bird's food supply might be able to provide some of this essential water but if the ground surface is covered with snow the bird also has difficulty in finding an adequate supply of its food. Householders are sometimes advised to put out fresh water supplies for birds in winter but in a very cold spell even a bowl of warm water can become frozen within minutes. It is not very convenient to keep renewing the water in the bowl but under conditions of heavy frost this is necessary in order to keep a usable water supply available. The present invention was devised to overcome some of these problems by enabling water in a drinking trough to remain usable for a longer period of time in cold conditions. According to the invention, there is provided a bird drinking trough comprising a thermally insulated water bowl containing a float, the float being capable of covering substantially the whole exposed surface area of a body of water when this is present in the bowl, and the float including a cut out portion providing open access to a limited surface area of available water in the bowl for a bird to drink therefrom. The water bowl may be made of a thermal insulation material such as expanded polystyrene. Preferably, the float is also made of a thermal insulation material and has one or more drinking holes formed therein. The float may be formed with a recess at the base of the cut out portion in the region where the float comes into contact with the water surface. A further recess may be provided at the periphery of the float. In one embodiment, the float is provided with a cover which serves to protect the exposed area of the water surface from too rapid heat loss in conditions of strong winds. Conveniently, the cover is mounted on the float. The cover may be arranged to substantially enclose the upper surface of the float but in this case the cover is provided with an opening through which a bird may gain access to the drinking hole. The cover may be arranged to collect water from any rain that may fall on the drinking trough, such collected water being fed into the bowl of the trough. The trough may include an overflow outlet arranged so that above a certain depth of water in the bowl any excess water will be rejected. The cover may be secured to the bowl by a rod member which is fastened to the bowl on the axis thereof. The float may carry a wind vane such that the action of stray wind gusts will cause agitation of the float on the surface of water in the bowl. When a cover is present, the wind vane may be part of the cover. Preferably, the trough carries a food holder into which solid food material for birds may be placed. The food holder may be a basket having an opening which is positioned so that it is open when the trough cover has been raised. The drinking trough amy be provided with hanging means by which it may be attached to an overhanging tree branch and possibly also with bird perches to encourage use of the trough. By way of example, particular embodiments of the invention will be described with reference to the accompanying drawings, in which: Figure 1 is a plan view of a bird drinking trough, Figure 2 is a cross-secttaraLview taken on the line II—11 of Figure 1, Figure 3 is a side view partly in section of a different embodiment of trough, Figure 4 is an axial cross-sectional view of a further embodimen Figure 5 is an enlarged view of the trough of Figure 4 taken fro above and after removal of a cover and a food basket, Figure 6 is a partial cross-sectional view taken along the line VI-VI on Figure 5, and, Figure 7 is a detail of a marker that may be carried on the floa to indicate when a manual refilling of the bowl may be necessary. The bird drinking trough that was constructed in accordance with Figure 1 view comprised a water bowl 1 of a fairly shallow, and circul shape which was intended to contain a body of water 2. The bowl was formed of a thermal insulation material which in this instance was expanded polystyrene. Lying on the surface of the water in the bowl 1 a float 3 which supported a wind vane 4. The float v/as also formed o expanded polystyrene. The use of a structural material having good thermal insulation properties ensured that the body of water 2 that wa substantially surrounded by this material would lose heat only ery slowly in cold conditions and thus would remain effective as a drinkin O P ? trough when other water supplies had become frozen. The bowl 1 included a water overflow outlet 5 and was provided with a flat base 6 for enabling it to be placed on a low wall or bird feedin table for convenience in use. The float 3 included four drinking holes 7 which were symmetricall spaced round the circumference of the bowl although each hole 7 was of elongated shape with the major dimension of the hole lying on a radius the float. This arrangement of the holes 7 with the long edges of the holes lying roughly on radii of the float ensured that for a given angular movement of the float about its axis (caused by the action of wind gusts on the vane 4) there would be a maximum disturbance by the edges of the exposed surface of water so that any formation of ice woul tend to be retarded. The inner and outer ends of the holes 7 had rounded shapes and thi provision helped to ensure that any areas of ice that might be formed a the holes under freezing conditions would readily break away from the holes and the ice pieces would then become distributed over the water surface beneath the float 3. Since these ice pieces tended to be of a lozenge shape, random movements of the float about its axis caused agitation of the water surface and the ice pieces became turned unt they were arranged with their long axes normal to the float radius. Th alignment of the ice pieces helped to keep the exposed water surface unobstructed by ice and thus prolonged the time that the trough could b used for drinking in freezing weather conditions. The lower side of each hole 6 was formed with a recess 8 in the region where the float came into contact with the water surface. It ha been found that the provision of such a recess 8 tended to conserve hea and prevent undue heat loss at the exposed water surface and so delayed any formation of ice at the hole. A similar recess 8 was provided at t outer edge of the float 3. The float 3 carried a central column 9 which supported the wind va 4 and the float was attached to the bowl 1 by a pin 11 that allowed fre vertical movement of the float so that it would always lie in contact with the surface of water in the bowl. The wind vane 4 ensured that in the open air when gusty wind conditions were present the float would be kept constantly moving on the water surface so that the formation of ic in freezing conditions would be retarded. In operation of the drinking trough, the user would place it on a bird feeding table or low wall, fill the bowl with water until excess water emerged from the overflow outlet and then leave the trough for th use of the local wild birds that would thereby become attracted to visi the garden or balcony where the trough was situated. When the weather warm, the provision of the float 3 on the water in the bowl served to reduce evaporation from the water surface and thus tended to retain the water longer than an open bowl would do. When the weather is cold, the float aided the retention of heat in the body of water in the bowl so that the formation of ice was retarded. Motion of the float 3 on the water surface caused by gusts of wind catching the wind vane 4 also serv to retard the formation of ice and prolong the time that the drinking trough could remain a useful source of water to the local birdlife. In order for the trough to retain its. usefulness it is necessary for the trough to be inspected at intervals and for the water level to b topped up as the water is taken for drinking. To reduce the frequency a which manual topping up might be required some further embodiments were constructed. Figure 3 shows a trough having a bowl 1 including a water overflow outlet 5 and which carried three perches 12 upon which a bird 13 could alight for using the trough. The trough in this embodiment was intende to be suspended from an overhanging tree branch and it was carried on four vertical strings 14 held apart by a hoop 16 and connected by a rin 17 to a suspension string 18. Each vertical string 14 passed through a hole in the periphery of the bowl and was secured to a bead 19 located beneath a metal washer at the edge of the bowl. The float 3 was provided with two drinking holes 7 and the upper side of each hole carried a concave portion 21 arranged so that any splashes of water made round the edge of the hole would tend to drain water back into the bowl to minimise wastage. The lower side of each hole 7 was formed with a recess 8 in the region where the float came in contact with the water surface. It has been found that the provision o such a recess 15 tended to conserve heat and prevent undue heat loss at the exposed water surface and so delayed any formation of ice at the hole. The float 3 carried a cover 22 which included two entrances 23 through which a bird using the trough could pass in order to stand on t float 3 and drink at the holes 7. In use of the drinking trough of the invention, it has been found that freezing and also evaporation of the drinking water is prevented a delayed. Additionally the formation of algae in the drinking water is delayed. The trough having a cover in the region of the drinking holes serves to protect the water surface from snow and dirt and during a rai spell the domed top of the cover serves to catch rain drops and direct these into the bowl 1. The trough can thus be replenished and flushed out by the rain so that frequent manual intervention may not be necessary. This flushing out process also helps to remove stale water from the trough. When a bird using the trough is standing on the upper surface of float 3 the water level is always at a constant distance beneath the f of the bird and this arrangement has been found in practice to give th bird confidence in using the trough since it will soon learn that a reliable source of water is available at the trough when other supplie have become dry. To encourage birds to use the trough a bag for food such as nuts seeds could be hung inside the cover 22. A different model of drinkin trough which specifically incorporates a food container was also devised. This construction is shown in Figures 4 to 7. As depicted in Figure 4, the water bowl 1 was supported by a centr metal rod 24 which was screwed into a plastics plug 26 in the centre o the base 6 of the water bowl 1. The plug 26 had two othogonally dispos holes which supported two wooden rods that extended beyond the periphe of the bowl 1 and the ends of which thus together formed four perches 1 for the use of birds at the trough. The middle portions of the rods we accommodated in grooves (not shown) that were formed in the base 6 of t bowl 1. The bowl also included a water overflow outlet 5 which was located on a central boss of the bowl and which served to prevent the height of water in the bowl from rising above a predetermined level. The float 3 in this embodiment included a central hollow portion 2 arranged so that when the bowl 1 became empty.the hollow portion 27 wou be able to accommodate the boss of the bowl and thus allow a compact packing arrangement for the trough. Two drinking holes 7 were provided in the float 3 and in this embodiment the holes had a slightly raised rim 28 portion. At the lowe end of each hole 7, the recesses 8 were located in the places where the OMPI holes met the surface of the water 2. A cover 22 supported on the float 3 in this embodiment was provide with a wind vane 4 which served as a handle for the cover and also as means enabling the float to be agitated as well as aligned to a certain extent with the prevailing wind direction. The cover 22 and the float both supported low friction bushes 29 so that the float would be kept freely rotatable about the rod 24 without any undue wear taking place. The cover 22 and float 3 included two bird entrances 23, only one of which is depicted in Figure 4. The action of wind on the vane 4 of the cover served to a certain extent to keep the float 3 turned so that the bird entrances 23 would b moved away from facing directly into the wind. This would thus help to conserve heat within the space enclosed by the cover since this is kept sheltered from the full force of the wind. In addition, wind gusts acting on the vane 4 will cause rapid movements of the edges of the drinking holes 7 on the water surface so that this surface is disturbed repeatedly and any formation of ice in cold weather tended to be retarded. When approaching one of the entrances 23, a bird would be able to see a food basket 31 which was supported by a collar 32 on the rod 24. The bird would thus be attracted towards the drinking trough and would find food and water conveniently placed. In order to enable the food basket to be refilled when necessary, the cover 22 was able to be lifte from its.-, place on the float 3 and the cover could then be moved upward on the rod 24 sufficiently to allow more food to be added to the basket 31. The rod 24 was of a suitable length to allow this action and the to of the rod carried a ring 17 by which the trough could be suspended fro a convenient tree branch or wall bracket. In replacing the float cover 22 the lower edge of the vane 4 is engaged in a notch 34 in the upper wall of the float and this notch thus ensures correct alignment of the cover on the float. Figure 5 is a view from above the float 3 in the bowl 1. The drinking holes 7 were located on concave portions 21 which allowed wat splashes accidentally made by a bird at the trough to re-enter the bowl 1. Around each concave portion 21 the rim 28 portions had a slightly raised profile and these rims had the function of restraining dropped food pieces from falling into and being washed into the water in the trough. This helped to prevent early contamination of the water. A significant proportion of the dropped food pieces therefore were retain outside the drinking hole 7 by the rims 28 and these dropped pieces wer eventually blown away by stray draughts of air within the cover 22. It will be noticed that the drinking holes 7 have long edges that lie along radii to the axis formed by the rod 24 of the trough. The provision of these radial edges to the holes 7 ensures that for a given amount of angular movement of the float 3 about the rod 24 there will b a maximum disturbance by these edges of the exposed surface of water so that any formation of ice will tend to be retarded. The profile of the float 3 around each drinking hole 7 can be seen more clearly in Figure 6. It will be observed in Figure 6 that the recess 8 extends substantially over the area of the float 3 that is beneath the concave portion 21. The recess 8 in plan is segment-shaped and its shape corresponds to that of the concave portion 21 as depicte in Figure 5. The use of a recess 8 which thus extends beyond the area the drinking hole.7 has been found to be beneficial in retarding the formation of ice at the hole 7 in freezing conditions. Figure 7 is a pattern of a marker 36 which was carried on the oute wall of the float 3 to indicate the level of the float with respect to the upper rim of the bowl 1 and which thus would indicate the height o water in the bowl. In the position depicted in Figure 7, the level o water is sufficient but a departure from this condition by a partial 5 disappearance of the circular pattern would indicate that manual refilling was necessary. In the embodiment constructed, the float 3 was made by a mouldin operation and the marker 36 was conveniently formed simultaneously du this operation by a suitable shaping of the mould surface. This , Q provision helped to reduce the cost of manufacture of the trough. The bird drinking trough of the invention has been found to be useful to birds in the garden since it can offer both food and drink these services can still be available in extremely cold weather when other sources cannot be used. The trough thus offers very practical 15 to birds at all seasons of the year and it could assist in preventing bird deaths in the winter. Since only a small part of the available water surface is exposed to the air, this helps to reduce the loss of water by evaporation which can occur in warm weather conditions. The provision of fresh water for birds is also necessary of course during 20 drought conditions in the summer. The foregoing description of embodiments of the invention has be given by way of example only and a number of modifications may be mad without departing from the scope of the invention. For instance, ins of being made of expanded polystyrene, the major parts of the trough 25 could be made of some other suitable thermal insulation material such a polyurethane foam or even wood. The external walls of the trough m be given some suitable surface treatment to modify the appearance suc to blend in with woodland surroundings or to protect the insulation OMPI material from erosion. In the embodiment of Figure 1, the wind vane the column 9 could be replaced by one or more upstanding vanes locat between the drinking holes 7 on the float 3, for example.

Claims: CLAIMS 1 A bird drinking trough comprising a thermally insulated water bowl containing a float, the float being capable of covering substantially the whole exposed surface area of a body of water when this is present in the bowl, and the float including a cut out portion providing open access to a limited surface area of available water in the bowl for a bird to drink therefrom. 2 A trough as claimed in Claim 1, in which the water bowl is made of a thermal insulation material such as expanded polystyrene. 3 A trough as claimed in Claim 1 or 2, in which the float is made of a thermal insulation material such as expanded polystyrene. 4 A trough as claimed in any one of Claims 1 to 3, in which the cut out portion of the float is constituted by one or more drinking holes formed therein. 5 A trough as claimed in any one of Claims 1 to 4, in which the float has a recess -at the base of the cut out portion in the region where the float comes into contact with the water surface. 6 A trough as claimed in any one of Claims 1 to 5, in which the float has a recess at its outer periphery in the region where the float comes into contact with the water surface. 7 A trough as claimed in any one of Claims 1 to 6, in which the float is provided with a cover. 8 A trough as claimed in Claim 7, in which the float includes a cover having an opening through which a bird may reach water in the bowl. 9 A trough as claimed in Claim 7 or 8, in which the cover is arranged to direct into the bowl of the trough a proportion of any rainfall water at a time when rain is falling on the cover of the trough. 10 A trough as claimed in any one of Claims 1 to 9, in which the bowl includes an overflow outlet arranged such that above a certain d of water in the bowl any excess water will tend to be rejected. 11 A trough as claimed in any one of Claims 1 to 10, in which the float carries a .wind vane such that the action of stray wind gusts wi cause agitation of the float on the surface of water in the bowl. 12 A trough as claimed in any one of Claims 1 to 11, in which the trough carries a food holder into which solid food material for birds may be placed. 13 A bird drinking trough substantially as described with reference to any one of the accompanying drawings.

Inventors: STEER CLIVE ALLEN, STEER, CLIVE, ALLEN
Applicants: STEER CLIVE ALLEN, STEER, CLIVE, ALLEN
Application year: 1984
Main classification: A61K39
IPC codes: A01K7, A01K39