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Publication numberUS2690028 A
Publication typeGrant
Publication dateSep 28, 1954
Filing dateFeb 2, 1952
Priority dateFeb 2, 1952
Publication numberUS 2690028 A, US 2690028A, US-A-2690028, US2690028 A, US2690028A
InventorsMullen Thomas W
Original AssigneeMullen Thomas W
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Rodenticide dispenser
US 2690028 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

Sept. 28, 1954 'r.-w. MULLEN RODENTICIDE DISPENSER 4 She'ets-Sheet 1 Filed Feb. 2, 1952 IvvENToR, 77-10MA5 W MQLLEN;

HFTOQNEX p 8, 1954 T. w. MULLEN 2,690,028

RODENTICIDE DISPENSER Filed Feb. 2, 1952 4 Sheets-Sheet 2 /7 I INVENTOR,

THOMAS W. MuLLE/v, F Ev WQ WW AFTOQNEY Sept. 28, 1954 1-, w, MULLEN 2,690,028

RODENTICIDE DISPENSER Filed Feb. 2. 1952 4 Sheets-Sheet 5 INVENTORY, 7F/oMAs W MuLLEN, 15v Mam A'FTomvEx Sept. 28, 1954 w, MULLEN 2,690,028


Patented Sept. 28,1954


Application February 2, 1952, Serial No. 269,635

8 Claims.

This invention relates to a device for dispensing a flowable dry state of bait either in a granu lated or meal form or in a liquid form. The primary purpose of the invention is to provide a dispenser which will not deter but which will be inviting to rats and mice. While different kinds of rat and mice killing baits may be employed, the structure is primarily intended to dispense baits in which is incorporated the chemical 3 (alpha-acetonylbenzyl) 4 hydroxycoumarin. This is the chemical which is being sold under the trade-mark Warfarin, as originated by the Wisconsin Alumni Research Foundation, and as more fully described in the U. S. Letters Patent No, 2,427,878, issued Sept. 23, 1947.

There is a form of rat behavior, advantage of which is taken in the devices forming the subject matter of this application. Unless the rat is extremely hungry due to absence of available feed, or the presence of feed only in open spaces, a rat will normally eat only where he can back up against something or be within some cover wherein there is no approach to his rear end. That is, when a rat eats, he wants an attractive hiding place such that he can watch from all directions the approach of any enemy, and he prefers two ways of escape, so that should an enemy come in from one direction, the rat can escape by another direction. The rat does want the direct approach to him covered if at all possible. A rat will depend upon such a hiding place for his protection whereas a mouse will depend somewhat on his speed in escaping from open places or places of hiding to get into other places of protection.

I have discovered that the ignoring of this I behavior of rats and mice has led to the failure of many types of dispensers heretofore available, and in my device herein shown and described provisions have been made to accommodate the dispensers to the inherent characteristics of the rats and mice accordingly.

A. peculiar characteristic of the bait containing the above indicated chemical is that rats and mice eating the bait containing that chemical do not die at once, and neither do they die directly from poisoning by use of that chemical. To the contrary, the rats and mice will have to return again and again to the bait to be carried by the dispenser before any apreciable effect is had upon them. In fact, the chemical kills the rats and mice by changing the clotting ability of their blood. In other words, the rats and mice do not die directly from the poisonous effect of the chemical, but rather from its consequences in that their blood fails to have the clotting ability, and progressive hemorrhaging sets up Within their intestinal track so that the rats and mice gradually become weaker and weaker until they finally die. For this procedure to take place, a time element of from five to fourteen days approximately is required to cause the individual rat or mouse to die. That means that these animals have to return again and again to the dispenser to keep up the supply of the material which is causing their condition leading to their death. Under that operation of the chemical, the rats particularly do not become shy and suspicious of the bait dispensing devices, but instead build up a confidence to return again and again to the dispensers providing they are properly constructed and operate in accordance with rat or mouse psychology.

, The chemical indicated will kill any mammal or fowl taken in sufiicient concentrations over a sufficiently long period of time, but the material is in such small concentration in the bait required to kill rats and mice, that it is extremely unlikely that farm animals, dogs, and cats, will be harmed from occasional exposures to or the eating of the bait.

However, it is well to prevent any accidental exposure of the bait such as might occur by upsetting of the usual bait dispensers heretofore employed, so that there will be no opportunity for the build up effect of the bait to occur in any animal accidentally obtaining access thereto. The invention herein shown and described is especially designed to not only dispense the bait in accordance with the catering to the desires of the rats and mice, but also to prevent accidental exposure of the bait to other animals.

A further primary object of the invention is to provide a dispenser which may be used out of doors as well as indoors and which will keep the bait dry in either exposure. Also it is an important object of the invention to provide a dispenser which may be detachably secured in place so that it will not be accidentally overturned, and yet will be readily handled so that it can be reversed for bait filling.

With these fundamental matters briefly indicated, further appreciation of the invention will become apparent from the following description of the invention as illustrated by the accompanying drawings, in which Fig. 1 is a view in entrance side elevation of a structure embodying the invention;

Fig. 2 is a fragmentary top plan view in partial section of the structure;

Fig. 3 is a View in elevation of the structure similar to that shown in Fig. 1, but in fragmentary and sectional showing;

Fig. 4 is a view in central diametrical vertical section on the line l 5 in Fig. 3;

Fig. 5 is a fragmentary top plan View in partial section of a slightly modified form of the invention;

Fig. 6 is a diametrical vertical section on the line 6-6 in Fig. 5;

Fig. '7 is an entrance side elevation in partial section of a modified form of the dispenser to employ a liquid bait;

Fig. 8 is a view in top plan of the bait pan and support; and

Fig. 9 is a view in central Vertical section on the line 9-9 in Fig. 8.

Structure form of Figs. 1-4

A shell or dome-shaped housing I5 is formed any suitable manner to have a central area E6 planar in shape across the top side, and to be entirely open from its underside. Preferably there is .outturned a short flange I! from around the marginal lower edge of the housing I5. This housing i5 is preferably made out of metal so as to be extremely durable. The side wall i8 is essentially cylindrical in shape.

Through this side wall [8, there is provided an entrance is, herein shown as having an upper semi-circular arched confirmation with straight side walls 20 and 2! extending therebelow. This entrance is is provided such as by punching through the wall I8. It has an area sufiiciently large to permit a rat as well as a mouse to enter therethrough to the interior part of the housing i5, when the flange side 57 is resting on the floor or the ground. It is to be noted that there is but one of these entrances I9 provided.

The cutting through the wall I8 to provide this entrance It not only provides the opening as the rodent entry into the housing I5, but it also introduces another factor in that the formerly rigid wall it can then be elastically sprung circumferentially somewhat for two different functions as will be described.

The first function of the elastically circumferentially expandable or selectively distortable wall E8 is to permit the securing to the wall It so as to be carried thereby, a cross arm 23. This cross arm 23 may take any suitable cross sectional shape, herein shown as having a U-section, and is provided with end tongues 24 and 25 which may be carried through slots 26 and 21 provided in the wall I8 as indicated primarily in Figs. 2 and 3. The downturned portion 28 of the bar 23 serves as an abutment against the inside of the wall IS so that the normal elasticity of the wall l8 will cause the wall to spring back against the abutting portion 28.

In the form being described as relating to Figs. 1-4 inclusive, this bar 23 extends diametrically across the housing I5. Furthermore, the bar 23 is located by the slots 25 and 21 to be in that position wherein the opening [9 is centered on an axis at right angles thereto.

A bait pan 3D, herein shown as consisting essentially of a cylindrical cup with a substantially fiat bottom, is mounted on and fixed to the bar 23 centrally thereof. The top side of the bar 23 is spaced above the underside of the flange ii a slight distance such as approximately threequarters of an inch. The diameter of the cup A. 30 exceeds the dimension of the transverse width of the opening I9.

The flat area I6 of the housing It is provided with a circular opening 3 I therethrough, of a suiiicient diameter to permit the entrance of the mouth end 32 of a bait storage receptacle In practice it is quite convenient to use as this receptacle 33 any one of the standard sizes of Mason jars, such as the one-half pint, the pint, the quart, the half gallon, and even the one gallon sizes thereof. The diameter of the opening 3! is fur ther such that the annular exterior rib 34 of the receptacle 33 may rest against the margin of the opening 3! through an intervening rubberlike gasket 35 as a sealing means therearound. The mouth piece 32 extends on through the top side area N5 of the housing l5, and receives screw threadedly thereon a tube 36. The assembling of the receptacle, its gasket 33, and the tube is made in connection with the housing i5 prior to the assembling of the bar 23 and its cup 38 with the housing I5. The assembly of the jar or receptacle 33 and the tube 36 with the housing i5 is preferably made with the parts reversed from the positions shown in Figs. 1-4, that is in the upside down conditions, because the recep tacle 33 will be previously filled With the bait to be dispensed, or at least a portion of the bait to be dispensed will be carried within the receptacle Then after those parts are assembled with the housing I, the cross bar 23 and its cup 353 may be assembled with the housing i5 as above described, whereupon the assembly may be returned to its upright position as indicated in the various views in Figs. 1-4.

The length of the tube 36 is made to be such that it will terminate a distance above the floor 31 of the cup 30 as indicated proportionally in the views shown in Figs. 3 and 4 so that the feed or bait may drop down from the receptacle 33 through the tube 36 and rest on the floor Bl with the material flaring out from the lower end of the tube 36 to its normal angle of repose. The diameter of the cup 3% is made to be sufiiciently large so as to permit the ready entrance of the rats nose and month between the cup 3t and the side wall of the receptacle 3% so that the rodents may have access to the bait falling down into the cup 30.

Preferably there is provided a device for overcoming any bridging action of the bait within the receptacle 33. In the form herein shown this device consists of a wire generally designated by the numeral 38 shaped to the form wherein there is a central lower cross bar 39 from the outer ends of which the wire is bent upwardly and diagonally inwardly to cross by the legs ill and 4!, the spacing apart of the extreme upper ends 12 and 43 of the wire being such that they have to .be pressed inwardly one toward the other to permit them to be entered through the mouth end 32 of the container 33 whereupon they may spring outwardly within the container or receptacle 33. The cross bar 39 is of a length greater than the diameter of the inside of the tube 36 so that when this device 38 is dropped into the receptacle 33, it will rest on the then upper end of the tube 36 by reason of this overlength or" the bar 39. The device 38 is of course assembled with the other structure prior to the assembly of the cup 30 and its supporting bar 23 with the housing I5.

Should the bait become bridged over in the receptacle 33, the rat looking for more of the bait in the cup 30 will run its nose around therein .5 and will tend to push against the exposed end of the device 38, causing it to shift, and accordingly causing it to travel or agitate the material which is hung up in the receptacle 33, breaking the bridge allowing that bait material to drop down through the tube 36 to the cup 30. In fact, when the rat or mouse finds the cup 30 to be'empty, in his eager desire to get more food, he will become more frantic in pushing around in the cup 30 and thus will forcibly push around the lower end of the device 38 accordingly.

The tube 36 depending within the housing I5, together with the cup 30 and the cross bar 23, forms in effect a barrier or bafile centrally disposed inside of the housing [5, and centered on the opening l9. This bafile effect will often be entirely sufiicient to give the rat some feeling of security, because it is observed that he will always go behind the cup 30 to feed, that is he will go clear to the back side of the housing which is that side fartherest removed from the opening IS. The rat or mouse will eat from that back side of the cup 30 primarily.

But this baffie being somewhat incomplete, particularly since the bar 23 is necessarily spaced above the level of the ground or floor upon which the flange I! rests, may cause some apprehension on the part of the rodent and therefore it is preferable to provide a more complete bafiie.

This complete baflie is herein shown, Figs. 1-4, to be a plate 45 clownturned from an upper plate 45 which is carried against the underside of the fiat area 16 by fitting around the mouth portion 32 of the receptacle 33, and being compressibly forced upwardly thereagainst by the upper end of the tube 36. That is, the baffle members 45 and 46 form an L-shaped piece, the member 45 being substantially equal in transverse width to the diameter of the cup 30, and at least exceeding the transverse Width of the opening I9. The vertical height of the member 35 is approximately that of the distance from the underside of the flange H to the underside of the flat area 16.

Thus in providing the complete bafile member 45 in front of the cup 30, and spaced inwardly from the opening I9, all within the housing I5, the rodent has a complete concealment from view through the entranceway l9 when he is within the housing I5, and any enemy coming through the opening IE) will come around one side of the member 45 and will thus give the rodent a pathway of escape around the other edge of that member 45 and out through the opening it.

The second function of the opening l9 beyond its primary use as an entryway is to permit the side of the wall l8 to be sprung inwardly toward the bar 23 adjacent the opening walls or edges 20 and H. The flange N, Fig. 2, is provided with a substantially halfround notch 4'! adjacent the side of the opening I9, such as the side 29, and then diametrically across the housing a second notch 48, Fig. 4, is provided to be substantially halfround in shape.

Where the dispenser is to be used on floors into which nails may be driven, a nail (not shown) may be driven down to be partially within the back notch 48, and a second nail (not shown) is driven down to be partially within the notch 41 on the opposite side of the housing. These nails are not driven down sufliciently far to compressibly engage the flange I! with the floor, but are left sufiiciently loose so that the wall 18 adjacent the edge 20 of the opening l9 may be pressed inwardly to free the flange I! at that zone from engagement with the anchoring nail, and the housing l5 tilted upwardly so as to be pulled away from the opposite engaging nail in the notch 48. In other words, there has to be a forcible compression of the housing 15 substantially diametrically in the direction of the line between the notches 41 and 48 to release the housing I5 from its securing means.

The underside of the housing I5 is purposely left unclosed for the reason that in some instances the rodents will become so weakened and lethargic that they will not have sufficient energy to travel back out through the opening I9 after they have had sufficient effect of eating the bait. In that case, they may die within the housing I5, but they may be readily removed by lifting up the housing l5.

Structure shown in Figs. 7-9

Referring to Figs. 7-9, the fundamental structure remains the same as above described. This structure, however, is designed to use a liquid bait which will feed only as it is consumed. Of course such a liquid bait generally using water as the vehicle in which the material may be mixed or dissolved which is the effective hemorrhage-producing agent, will have to be used Where the dispenser is protected against freezing temperatures. Such conditions are encountered in zoos and heated buildings and warehouses which are rat infested.

In this particular construction, on the mouth end 32 of the receptacle 33, inside of the housing I5, there is screw-fitted a cap 49. In this case, a gasket (not shown) may be interposed between the cap and the underside of the member 45, if used, or directly against the underside of the central area flat portion I6. This is to secure an airtight connection. A tube 56 leads from the cap 49 downwardly by a length which will terminate in the cup 30 at a distance spaced above the fioor 31 to give the desired depth of the liquid to be carried in the cup 30.

In this form of the structure, it is still preferable to employ a baflie or screen spaced inwardly from the opening 29. While the side wall of the cup 30 may be carried sufiiciently high on that side at least presented toward the opening I9, the baifle shield 45 may be employed as indicated in Fig. 7, or there may be a substantially halfround shield or baffle 5| carried around the forward side of the cup 30, Figs. 8 and 9, and secured to the cup. In this case, the vertical height of the shield 5! will extend close to the plane of the underside of the flange I! as the lower limit, and will be carried upwardly at least beyond the top of the opening I9.

This particular form of the invention is provided to supply the rodenticide in the liquid form because in many instances the particular location of the rat infestation is removed from a source of supply of drinking water. Rats are particularly desirous of getting water along with their food, and oftentimes they will be attracted more readily by the presence of the water mixture or solution than where the bait is provided in the meal, flour, or granular form.

Structure as shown in Figs. 5 and 6 Referring to Figs. 5 and 6, the same structure as above described in reference to the dry bait dispenser is employed, the modification being that the cross bar 23 instead of being located to 7 be centered on the diametrical line of the housing l'is offset-tube on a chordal line centering less in length than the diameter of the housing l5.

As indicated in Figs. 5 and 6, the cross bar 123 is moved forwardly towardthe opening 1.9 so as to leave a greater space behindthe cup than is provided in the form shown in Figs. .1-4. Rats particularly seem to desire this space for more freedom in feeding, and also in havinga greater sense of security within which to maneuver to travel .aroundthe .depending tube 36 in case of emergency scare of attack.

Further, in the form shown in Figs. 5 and .6, the cup structure. shown in Figs. 8 and 9 employing the baflle member .5l directly securedto the'cup 3G is shown *since'it is quite effeotive'in this particular relationship. In this case, the cross bar 23 is replaced by a shorter cross bar 52, having tongues 53 andfi l extending through the side wall 18 of the housing l5.

Operation In all of the various forms of the invention structure herein shown and describedthe operation is fundamentally the same, namely that the dispenser is inverted in all cases when the receptacle is tobe filled initially and to herefilled later. Of course'the receptacle 33 being glass, readily provides a sight determination'of when the rodenticide has to be replenished. In an event, the receptacle 33 is unscrewed from the tube portion, and the'receptacle 33 is filled, and then the receptacle is screwed up from the under side of the inverted housing until it is secured in place, whereupon the entire assembly is reversed to have the receptacle in the upside down position as illustrated throughout the various views in the drawings. This applies equally as well to the liquid form of dispensing as it does to the solid flowing type of bait dispenser. The of the elastic gasket 35 in all of the various forms permits the dispensers to be used out of doors under all weather conditions with theexception of course of the liquid dispenser which has to be protected against freezing.

All'oftheiorms of the inventionprovide some insurance against accidental spilling of the bait outside of thedispenser, even including the liquid form of dispenser. .The baffles will effectively prevent theilow of material directly through the entrance opening is, so that normally there will not be access hadto the bait by any farm animal and the like.

Further it is to be noted that the entrance opening or openings into the dispenser are always located on the one side so that the 'housing forms a complete enclosure otherwise within which the rat ormouse may feel secure in preventing the approach of enemies from the rear, particularly because the rodent is then normally facing toward the entry side of the housing in any event, and can watch the approaches from either side or the baffle arrangement to his zone within which he is feeding.

Thus it isto be, seen that I have provided in the various forms the invention amost unique structure whiclris exceedingly simple inthat it has but very few elements, and these elements are quite readily manipulated, all to the end that the dispenser accommodates itself quite perfect- 1y to the normal habits of the rodents. The structures in any of the forms are substantially fool proof in the hands of an inexperienced person,..a-nd ,the'dispensers-may be used with a Y 8 very high degree of safetyin any-'locationwhereinathereisratiinfestation, as well as mouse'infestation.

Therefore, while :I have shown anddescribed the invention in the specific forms and. construction,it is obvious that structural variations may be employed withoutv departingfromthe spirit of theinvention, and .I therefore. donot desire to be limited to thoseprecise forms, beyondth limitations which may the-imposed by the following claims.

I claim:

:1. "Arodenticide dispenser-lcomprisinga domeshaped shell having a top si'de;area :from which extends downwardly a generally cylindrical wall to terminateby alower supporting edge; said wall having a rodent; entrance opening .therethrough a baitipanof lesseridiameter than-that of said wallymeans supporting saidpanzfrom said wall to maintain the pan'spacedbelowsaid1top side area ,and in spaced relation from said entrance Opening; a rodenticidenarrying :vesselhaviug an under side feeding :mouth, and extending externally abovesaid shell and engaged therewith; said vessel being-centered vover said pan to drop rodenticide :through the vessel gmouth onto said pan; and a baffie-membercarried by said shell and extending downwardly on thatside of said pan toward said entrance opening, toblock a line of lightfrozn said'entrance opening to the side of the pan opposite thereto.

2. A rodenticidedispenser comprising a domeshapedshell'having a top side .area from which extends downwardly-.2. generallyicylindrical wall to terminate by a :lower supporting edge; said wall having a rodent entrance 7 opening themthrough; abaitpan of lesser diameter than that of said wall; means sup-portingsaid pan from said wall tomaintain-the panspacedlbelow said top side area and in spaced relation from said entrance opening; a rodenticide carrying vessel having an underside feeding mouth, and extending externally. above said shell and engaged therewith; said vessel being .oenteredover saidpan to drop ro-denticidc through the vesselmouth onto saidpan; a bafilemember carried bysaid shell andextending downwardly on thatside of said pan toward said entrance opening, to block a line of sight from said entrance opening to the side of the pan opposite theretoyand a second line-ofsight baiile wider thansa'id opening and carried by said shell, interposedbetween the first baffie and said opening; both of said-baffles extending vertically across a portion at least of the space between-said pan and said'top side area.

3. The structure of claim 1, in which the lower end portion ofsaid baiiie-is located within the margin of said pan.

A. The structure-of claim 1,; in whichthe bafiie extends from said top sidearea to the plane of said side wall supporting edge; said bafiiehaving an area -the vertical definingedges-of-which are spaced apart a distance approximately equal to the diameter of said.- pan.

.5.. A rodenticidedispenser comprising a domeshaped shell having a -top. side area from which extends downwardly a generally cylindrical wall to terminate by a lower supporting edge; said wall .havinga rodent entrance opening therethrough;

abait pan of lesser: diameter-than that of said wall; means supportingqsaid panfrom said wall 9 nally above said shell and engaged therewith; said vessel being centered over said pan to drop rodenticide through the vessel mouth onto said pan; a bafile member carried by said shell and extending downwardly on that side of said pan toward said entrance opening, to block a line of sight from said entrance opening to the side of the pan opposite thereto; and a second lineof-sight bafiie wider than said opening and carried by said shell, interposed between the first bafile and said opening; both of said baffles extending vertically across a portion at least of the space between said pan and said top side area; said first baflie being confined to the space between said pan and said shell top side area; and said second bafiie being spaced from and extending vertically below said pan to substantially the plane of the supporting edge of said wall.

6. The structure of claim 5, in which said second baflle is attached directly to said pan, and has a lateral width approximately equal to the diameter of the pan; said first baffle having a lateral width less than the diameter of the pan.

7. The structure of claim 1, in which said pan supporting means comprises a bar having a shoulder and a tongue extending therefrom at each end of the bar; said tongues passing through said shell wall; said wall being elastic in nature and retaining said tongues therethrough by the wall elastically abutting said bar shoulders; and said pan being secured to said bar.

8. A rodenticide dispenser comprising a domeshaped shell having a top side area from which extends downwardly a generally cylindrical wall to terminate by a lower supporting edge; said wall having a rodent entrance opening therethrough; a bait pan of lesser diameter than that of said wall; means supporting said pan from said wall to maintain the pan spaced below said top side area and in spaced relation from said entrance opening; a rodenticide carrying vessel having an under side feeding mouth, and extending externally above said shell and engaged therewith; said vessel being centered over said pan to drop rodenticide through the vessel mouth onto said pan; a baffle member carried by said shell and extending downwardly on that side of said pan toward said entrance opening, to block a line of sight from said entrance opening to the side of the pan opposite thereto; and a rodenticide agitator resting on said pan; said agitator having a loose pan bearing lower cross member of greater length than the diameter of said vessel mouth, and having a pair of legs extending from the cross member through said mouth, the upper ends of the legs diverging within the vessel one from the other a distance less than the internal diameter of the vessel and greater than said mouth diameter.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 640,730 Smith Jan. 2, 1900 1,113,842 Sill Oct. 13, 1914

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US640730 *Nov 10, 1898Jan 2, 1900Walter B SmithPoultry-feeding device.
US1113842 *Jun 24, 1913Oct 13, 1914Clyde J SillRodent-exterminator.
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2860445 *Nov 4, 1955Nov 18, 1958Yates HershelRodent exterminating device
US4746033 *Nov 12, 1985May 24, 1988Peter MorelliniDispensing apparatus
US7987629 *Sep 29, 2008Aug 2, 2011Technicide, Inc.Rodent bait station
US9258991 *Sep 7, 2012Feb 16, 2016Harper Holdings, Inc.Rodent bait station
US20090139133 *Sep 29, 2008Jun 4, 2009Technicide, IncRodent bait station
US20110283600 *Nov 24, 2011Technicide, Inc.Rodent bait station
US20120324782 *Dec 27, 2012Technicide, Inc.Rodent bait station
WO1986002806A1 *Nov 12, 1985May 22, 1986Peter MorelliniDispensing apparatus
U.S. Classification43/131, 119/77
International ClassificationA01M25/00
Cooperative ClassificationA01M25/004
European ClassificationA01M25/00B1