Mouse trap

The trap has a ring shaped passage with a door which, when opened, extends into the passage so that a mouse can only enter the passage in one direction. A bait trail in the passage extends around to the back side of the door where it can be pushed closed by a mouse, or released by the mouse and closed by a spring. Magnetic or spring means are disclosed for holding the door in the closed position. An attractant dispenser is provided for dispensing fresh attractant near the back side of the door when the trap is to be used.

BACKGROUND OF THE INVENTION 
Although a tremendous variety of mouse traps have been devised, there are 
disadvantages with all types and a need still exists for improvements. 
Such traps should be reliable, easy and inoffensive to use, safe with 
respect to household pets and children, and yet be relatively inexpensive. 
The well-known spring trap which strikes and holds a mouse is inconvenient 
and somewhat difficult and dangerous to load. It is dangerous with respect 
to pets and children. It is an offensive task to handle and empty the 
trap. 
Another type of trap employs mouse actuated trigger arrangements for 
capturing a mouse within a container. While this is a desirable approach, 
many of the trigger mechanisms are too complicated, and the traps are 
often sufficiently expensive that it is impractical to dispose of them, 
and emptying the trap is an offensive task. 
Another method of trapping mice is by the use of sticky or gooey substances 
which hold the mouse captive until it dies of starvation. This approach is 
obviously messy and offensive. 
SUMMARY OF THE INVENTION 
The present invention satisfies the goals expressed above and avoids the 
disadvantages of earlier devices. Briefly stated, the trap of the 
invention includes walls which define a continuous loop path or passage, 
preferably in a compact ring shape. A door in a wall of the passage is 
moved into the passage in an open position when the trap is to be used, 
this allows the mouse to enter the passage, but the door blocks the 
passage in one direction so that the mouse is guided in the other 
direction. The mouse is attracted either by curiosity, bait or other 
attractant which is located behind the door in its open position so that 
the mouse is enticed fully into the trap. The mouse will push the door 
closed with its nose thereby being trapped within the passage, or the 
mouse will release the door and allow it to be closed by a spring. 
Preferably, the walls forming the passage and the structure forming the 
door are air-tight so that the mouse will suffocate within a short time. 
Consistent with this, the cross-section of the passage is preferably made 
just large enough to accommodate the mouse's body, but small enough to 
make it difficult or impossible for the mouse to turn around. However, it 
can continue to move around the closed loop path. This exertion hastens 
death. An air-tight seal around the door is obtained by the use of a 
viscous sealant or by a magnetic membrane. 
The door is provided with means for holding it in a closed position once it 
has been closed. In one arrangement, the door is hinged to a door frame, 
and a magnet is mounted on the door frame in position to attract a metal 
hinge structure on the door and hold the door closed. The door frame is 
slightly angled so that the door will remain in an open position by 
gravity. Thus, other means are not required for holding the door open with 
the magnetic arrangement. In an alternative door latching approach, an 
"over-center" spring arrangement is employed wherein the door is initially 
held in an open position by the spring, but when pushed slightly in the 
closed position will cause the line of force produced by the spring to 
shift so that the door is drawn to a closed position by the spring. In 
another form, the door is continuously urged closed by a spring but can be 
held open by a latch releasable by the mouse. 
Various forms of bait may be provided with the trap to form an attracting 
trail to guide the mouse into the trap passage. In a preferred form of the 
invention, a fluid dispenser is positioned in a wall of the trap adjacent 
the inside of the door with the door in its open position. The dispenser 
contains a small quantity of fluid which is attractive to a mouse and 
which will remain relatively fresh for an extended period of time. Thus 
when the trap is to be used, it is only necessary to dispense a quantity 
of the fluid into the passage adjacent the back side of the open door. 
Consequently when the mouse approaches the door it is attracted by the 
smell of the material, but cannot get at the material without entering the 
passage and traveling around to the back side of the door, and in 
attempting to eat or smell the attractant will push the door into its 
closed position. 
One of the important features of the invention is that the trap has been 
cleverly designed for low cost fabrication, such that it is practical to 
dispose of the trap with the mouse, thereby avoiding the disagreeable task 
of removing the mouse from the trap. One of the features contributing to 
the low manufacturing cost is that the trap passage is preferably made by 
vacuum forming a thin sheet of plastic into somewhat of a ring shaped 
shell which is open on one axial face. This face is closed by sealing the 
plastic member to a flat card. The door assembly is preferably made as a 
separate unit which is made with precision to ensure an air-tight closure. 
Preferably the attractant dispenser is simply made by two small, shallow, 
cup-like, flexible elements that are clamped together by a ring and 
mounted in a recess in the upper wall of the passage. A self-sealing hole 
in the inner dispenser wall enables the attractant to be dispensed into 
the passage simply by depressing the top wall of the dispenser to squeeze 
the substance out of the dispenser. In an alternative form of dispenser, a 
thumb tack-like valve element is manually raised to allow fluid to drip by 
gravity from a small chamber containing a quantity of the fluid attractant 
.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION 
Referring first to FIGS. 1 and 2, the main body of the trap may be seen to 
include an upper housing or shell 12 positioned on a flat card 14. The 
shell 12 is preferably vacuum formed from a thin sheet of plastic into the 
generally ring shaped structure illustrated having an upper wall 12a, a 
generally annular shaped outer side wall 12b, an outwardly extending 
horizontal flange 12c attached to the lower edge of the outer side wall 
12b, and an inner, downwardly extending projection 12d forming an inner 
annular wall. The outer flange 12c is suitably attached in an air-tight 
manner to the card 14 so that the shell 12 in combination with the card 
forms a continuous loop passage 16 for receiving a mouse. 
One portion 12e of the outer shell wall 12b is formed relatively flat so as 
to better cooperate with a door assembly 20 attached to the inside of the 
flat wall to close an entry hole 22 in the flat wall portion 12e. 
Referring to FIG. 3 as well as to FIG. 2, it may be seen that the door 
assembly 20 includes a frame 24 having a portion 24a that surrounds the 
entry 22 in the wall 12e and includes a ring section 24b that extends into 
the wall entry hole 22 and defines an opening 25. The frame further 
includes a hinge portion 24c having a pair of stub hinge pins 24d. A small 
flat permanent magnet 26 is secured to the frame 24 by a pair of lugs 24e, 
with the magnet being positioned between the hinge pins and the frame 
portion 24a. The door assembly 20 further includes a two-piece door 28 
having a generally flat cover portion 29 and a hinge portion 30. The cover 
portion 29 has a circular section 29a which covers the opening 25 in the 
door frame portion 24a. Formed integral with one edge of the section 29a 
is a support section 29b having a pair of spaced, horizontally, extending 
slots 29c. The door hinge portion 30 includes a pair of spaced lugs 30a 
having openings 30b for receiving the door frame hinge pins 24d. The door 
hinge portion 30 further includes a pair of spaced tabs 30c that extend 
through the slots 29c formed on support section 29b of the door cover 
portion 29. These tabs 30c are bent inwardly as shown in FIG. 2 to secure 
the door hinge portion 30 to the cover portion 29. 
As mentioned above, it is desirable that the door 28 form an air-tight seal 
with the door frame 24. For this purpose, the door 28, is formed on its 
outwardly facing surface with an annular bead or rib 29d that fits within 
an annular recess 24f surrounding the door frame opening, as may be seen 
from FIGS. 5 and 6. The recess is preferably filled with a viscous 
substance that will cooperate with the door rib 29d to form a seal. 
The door cover portion 29 and the door frame 24 are preferably formed by 
injection molding to provide the necessary precision, and they are formed 
of sufficient thickness to be rigid, in contrast to the thin, semi-rigid 
material used for the inexpensive, primary housing or shell 12. To further 
insure that an adequate seal is obtained while yet allowing for wide 
manufacturing tolerances in the door hinge mounting arrangement, the door 
hinge portion 30 and the door cover portion 29 are initially only loosely 
connected by inserting the tabs 30c of the hinge portion 30 into the slots 
29c of the cover portion 29. The cover portion 29 is then positioned in 
proper sealing relation with the door frame 24 with the rib 29d in the 
recess 24f and with the hinge portion 30 properly positioned onto the door 
frame hinge pins 24d. With the parts thus properly positioned, the door 
hinge portion tabs 30c are bent 90 degrees by a suitable tool (not shown) 
to the position illustrated in FIG. 2, fixing the door portions 29 and 30 
in proper relation. This method provides a precision fit with wide 
tolerances in a low cost manner. The door hinge portion is made of steel 
for strength and also to be attracted by the magnet 26 on the door frame 
24. 
As may be seen from FIG. 1 and FIG. 2, there is an attractant dispenser 36 
positioned in a recess 12f in the upper wall of the main shell 12. This 
recess is located immediately adjacent to the door hinge and above and 
near the back side of the door 28 with the door in its open position as 
shown in FIG. 4. Referring to FIG. 7, the dispenser is very simply but 
cleverly designed, being formed of two shallow cup-like members 37 and 38 
which are placed in face-to-face relation so as to define a chamber for 
holding the attractant. A cylindrical portion 37a of the lower member is 
sized to fit through a hole in the bottom of the recess in the upper wall 
12a of the shell 12 as may be seen in FIG. 7, with an outwardly extending 
flange 37b on the lower member 37 engaging the bottom of the recess. The 
flange 38b on the upper member 38 engages the flange 37b on the lower 
member, and both flanges are confined by a retaining ring 44 which fits 
over the flanges and is attached to the bottom of the recess by sonic 
welding, adhesive, other suitable means. 
The dispenser cup-shaped members are formed of a resilient plastic or 
rubber material that is self-sealing with respect to small holes that may 
be formed in the material. This characteristic lends itself to a 
simplified method for forming an outlet in the dispenser while at the same 
time filling the chamber with the desired attractant. For this purpose, 
there is employed a syringe (not shown) having a small diameter needle 46. 
This needle, as illustrated in FIG. 7, is inserted downwardly through the 
end walls of each of the cup-shaped members 37 and 38 to the broken line 
position 46a illustrated in FIG. 7. The needle is then partially withdrawn 
to the point where the end of the needle is open to the chamber 40. A 
desired attractant is then injected into the chamber, following which the 
needle is withdrawn from the upper member 38 of the dispenser. Due to the 
resilient, self-sealing characteristics of the material, the attractant 
does not leak from the dispenser chamber through the holes formed by the 
needle. This is somewhat related to the attractant employed. It has been 
found that a suitable material is peanut oil, since it is attractive to 
mice and will retain a fresh smell over an extended period of time. The 
viscosity of the oil also helps to prevent leakage through the small holes 
48 and 49 which were formed by the needle as shown in FIG. 8. When it is 
desired to dispense some of the attractant, it is only necessary to 
depress manually with one's finger the dispenser member 38, as illustrated 
in FIG. 8. This action reduces the volume of the chamber creating a 
pressure which forces some of the fluid 50 to be dispensed downwardly as 
illustrated in FIG. 8. 
As an alternative approach for filling the dispenser chamber 40, the needle 
may be inserted only through the lower wall 37 and then withdrawn. Such 
needle should be provided with a vent tube to permit air to escape from 
the chamber 40 as an oil is injected. 
Operation 
The trap is normally purchased and stored in the condition illustrated in 
FIGS. 1, 2 and 4, wherein the door to the trap is closed. When it is 
desired to use the trap, it is only necessary for the user to push the 
door inwardly into the phantom line open position shown in FIG. 4, wherein 
a mouse can enter the passage within the trap but can only move in the 
direction indicated by the arrows 52, shown in FIG. 4. The door will 
remain in the open position since the wall in which the door frame is 
mounted is angled slightly outwards from the bottom so that the door will 
be kept open by gravity. More positive means may be provided to hold the 
door open if desired, but it is preferable to keep the device as simple 
and inexpensive as possible. 
The trap is useful without bait or attractant in that a mouse being 
naturally curious may well enter the trap even without any other 
attractant. Nevertheless, a trail of bait 54 is attached to the floor of 
the trap by suitable edible adhesive as shown in FIG. 4; and to provide a 
fresh smell for attracting the mouse, the dispenser is depressed in 
positioning the trap so that a quantity of attractant 56 is sprayed onto 
an area of the floor immediately behind the back side or inside of the 
door as illustrated in FIG. 4. 
When a mouse approaches the trap, it will be attracted by the bait on the 
floor of the trap immediately inside the door, and will also be attracted 
by the smell behind the door. Since the area behind the door cannot be 
directly reached because of the door blocking the path, the mouse is 
directed in the path indicated by the arrows. The cross-section of the 
path is sized such that it is just large enough to accommodate a mouse but 
it is sufficiently small that it is impossible or very difficult for the 
mouse to turn around. Of course, the mouse is enticed to go forward in any 
event in view of the bait and the fresh smell of the attractant 56. The 
length of the annular passage 16 within the path is sufficiently long that 
the mouse's entire body and its tail will be within the passage before the 
mouse's nose reaches the area 56 of fresh peanut oil behind the door 28. 
The annular passage is advantageous from the standpoint that a path of 
considerable length can be obtained with a compact package. 
The mouse when investigating the attractant 56 will either deliberately or 
inadvertantly push the door towards the closed position. The mouse does 
not necessarily have to push the door 28 completely closed because as the 
door starts to close, it is attracted by the magnet 26 on the door frame 
24 which helps pull the door closed and keep it closed. An air-tight seal 
is formed by the door by way of the rib 20d on the door cooperating with 
the sealant in the recess 24f in the door frame 24, as explained above in 
connection with FIGS. 5 and 6. Since the plastic upper shell 12 and the 
lower card 14 are hermetically sealed, the trapped mouse will very quickly 
suffocate. If an air-tight seal is not obtained, the mouse is still 
trapped and will soon die because of dehydration. 
When the user inspects the trap, it can be seen that the door is closed 
indicating that a mouse has been trapped. Also, the upper shell 12 of the 
trap is preferably made of a semi-opaque material such that it would be 
apparent whether a mouse was inside the trap, but yet it would not be 
totally visible. Although the material could be totally transparent, the 
semi-opaque approach is preferable for most people. Of course it would be 
apparent if a mouse carcass is in the the trap by lifting it an shaking 
it. If in any event a mouse is present, it is practical to discard the 
entire trap since it is inexpensive. The mouse can be removed and the trap 
reused if desired. 
Alternative Arrangements 
FIGS. 9 and 10 illustrate an alternative door assembly for the trap wherein 
a so-called "over-center" spring arrangement is employed. More 
specifically, a coil tension spring 60 extends between a hook 62 on the 
back side of a door 64 and a hook 66 on the back side of a door frame 68. 
The location of the attachment points for the spring are such that when 
the door is pivoted on its hinge to the open position shown in FIG. 9 by 
phantom lines, the door is positively held open by the spring 60 since the 
line of force along the centerline of the spring is on the side of the 
hinge axis 70 which holds the door open. The opening travel of the door is 
limited by the door engaging the inner passage wall of the trap, as shown 
in FIG. 4. When the mouse pushes the door slightly in a door closing 
direction, the spring attachment hook 62 on the door moves towards the 
door frame causing the center line of the spring force to cross over to 
the door closing side of the hinge axis 70 so that a force is produced 
positively pulling the door into closed position, as may be seen in FIG. 
10. This arrangement works satisfactorily, but is slightly less desirable 
than the FIG. 3 arrangement because of the tendency of a mouse to gnaw at 
protrusions such as the hooks upon which the spring is attached. Also, 
from an assembly and reliability standpoint, the magnetic approach is 
deemed to be slightly preferable. 
FIGS. 11, 12 and 13 illustrate an alternative form of a dispenser for the 
mouse attractant. A shallow conical wall 80 is formed in the upper wall 82 
of a trap wall. The attractant 84 is inserted into this well and the upper 
opening of the well is closed by a cap 86 which fits within the upper end 
of the well 80. A thumb tack-like valve 88 extends through a central 
opening in the cap, and the lower end of the valve stem 88a extends 
through an outlet 85 in the lower end of the well, as seen in FIG. 12. To 
release attractant, it is only necessary to pull the valve stem upwardly, 
as illustrated in FIG. 13 by gripping the valve stem head. The diameter of 
the hole 85 in the bottom of the well is sufficiently large that the 
attractant will drip by gravity. Retainer projections 88c on the valve 
stem prevent the stem from being accidentally withdrawn. While this 
alternative approach is inexpensive, as is the arrangement described 
above, it is slightly less desirable in that it is believed that 
depressing an actuator is slightly more convenient than having to raise 
the valve stem. 
It should be recognized that both forms of the attractant dispenser 
described are useful in other products as well as the particular mouse 
trap illustrated herein. Such arrangement may be useful in any trap or 
other apparatus in which it is desirable to dispense a fresh attractant 
material to entice any animal, rodent or pest. For example, it may be 
useful in a rodent feed station or a trap for flies or other insects. 
Similarly, the structure may be useful in totally unrelated devices in 
which it is desirable to have a low cost manually operated dispenser in a 
mass produced product. 
FIGS. 14 through 18 illustrate another arrangement for holding a trap door 
open and for holding the door closed. Also included is an alternative door 
sealing arrangement. More specifically there is shown in FIG. 14 an 
elongated leaf spring 90 made of metal or plastic. One end 90a of the 
spring is attached by adhesive or other suitable means to the flat card 14 
forming the bottom wall of the trap. A crease 90d is formed in the spring 
90 adjacent the end 90a which causes the other end 90b of the spring to be 
elevated slightly from the bottom wall 14 in cantilever fashion. As may be 
seen from FIG. 17, the spring end 90b includes an upwardly extending latch 
portion 90c for holding the door 92 in open position. 
Referring to FIG. 15, a door frame 94 is formed with a post 96 staked to 
the end of the door frame adjacent the hinge pins 97. A metal leaf spring 
98 is mounted to the door frame 94 by means of a hold in one end of the 
spring 98 which fits over the post 96 on the door frame. The leaf spring 
98 urges the door 92 into its closed position. 
The door frame 94 includes a magnetic plastic ring 100 which is pressed or 
bonded around the inside of the opening in the door frame. Referring to 
FIG. 16, the door includes an annular groove 102, which is covered by a 
flat ring-shaped magnetic membrane 103 that is held in position by an 
annular bead or lug 104 formed on the door inwardly slightly from the 
annular groove. The membrane 103 is preferably formed of Mylar or some 
other such magnetic material. The membrane need only be about three to 
five thousandths of an inch thick. 
In using the trap door arrangement of FIGS. 14-18, the door 92 is manually 
moved to the open position against the urging of the leaf spring 98. The 
door is held in this open position by the latch 90c on the leaf spring 90, 
as seen in FIG. 17. When a mouse enters the trap following a bait trail 
around to the back side of the open door, the mouse's weight on the leaf 
spring 90 will depress the latch 90c, releasing the door and enabling it 
to close in response to the urging of the door spring 98. The door opening 
is sealed by the thin membrane 103 engaging the magnetic ring 100 around 
the door frame 94 as shown in FIG. 18. The annular groove 102 in the door 
is aligned with the ring so that the membrane is free to make good 
magnetic contact with the magnetic ring to ensure an adequate seal.