AU737146B2

AU737146B2 - Dual-position lock for securing cages in a ventilated cage and rack system

Info

Publication number: AU737146B2
Application number: AU89610/98A
Authority: AU
Inventors: John E. Sheaffer
Original assignee: Lab Products Inc
Current assignee: Lab Products Inc
Priority date: 1997-10-31
Filing date: 1998-10-29
Publication date: 2001-08-09
Anticipated expiration: 2018-10-29
Also published as: GB2332701B; GB9823789D0; AU8961098A; CA2252273A1; GB2332701A

Description

P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990

A

A.

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ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: "DUAL-POSITION LOCK FOR SECURING CAGES IN A VENTILATED CAGE AND RACK SYSTEM" The following statement is a full description of this invention, including the best method of performing it known to us:- DUAL-POSITION LOCK FOR SECURING CAGES IN A VENTILATED CAGE AND RACK SYSTEM BACKGROUND OF THE INVENTION This invention relates to an improved dual-position lock for securing a cage in a ventilated cage and rack system, and in particular to a lock for accommodating different sized cages within a rack.

Ventilated cage and rack systems used to store animals are well known in the art. Typically, such systems include a plurality of shelves, each shelf containing a plurality of cages which provide air and/or water to the animals stored therein.

The cages are generally removable from the rack to provide access to the animals for feeding and testing, and to the cages for cleaning, maintenance and transport. To accommodate these requirements, rack systems are typically designed so that the cages can slide in and out of the rack system. When access to an animal and/or cage is not so required, the cage is locked in place in the rack to prevent the cage from inadvertently sliding out from the rack which can cause suffocation of the animal S within the cage by a disruption in air supply or dehydration of Sthe animal by a disruption of water to the cage drinking valve.

To enhance versatility, rack systems are sometimes designed to support cages of different sizes. To accommodate different cage sizes in the same rack system, a locking mechanism that can be easily adapted to different cage sizes is desirable. In one such dual-position lock, sold by Lab Products Inc., the locking -1 amechanism includes a base member rotatably attached to the rack system and a retaining member rotatably attached to the base member. The base member is disposed in a locking position such that a foot connected to the retaining member is interposed within the slide path of the cage to lock the cage within the rack system. In the unlocked position, the base member is rotated such that the cage may be freely inserted into or removed from the rack. To accommodate a different size cage in the rack, the retaining member is rotated with respect to the base member so that in the locking position, the foot is interposed at a different position within the slide path. Thus, a single locking 00mechanism can lock cages of different sizes.

0c While the prior art dual-position locks worked for their intended purposes, a significant drawback of the prior art lock described above is that the lock has to be grasped in order to o switch it between the locked and unlocked positions. Another Sproblem with the prior art lock is that changing the position of 00': the lock to accommodate a different cage size is cumbersome 0.: because it requires an operator to pull the retaining member away S from the base member while at the same time rotating the retaining member 180 degrees. Yet another problem with the prior art lock is that it is sometimes difficult to determine whether the locking mechanism is in the locked or unlocked position without carefully observing the locking mechanism especially on smaller cages that are recessed into the front of the unit. By constructing a dual-position lock in accordance with the present invention, the drawbacks of the prior art locking mechanisms are overcome.

SUMMARY OF THE INVENTION The present invention is for an improved dual-position lock for securing cages in a ventilated cage and rack system that is significantly easier to lo6ck/unlock, to adapt for different cage sizes and to determine visually whether the lock is in a locked or unlocked position. In accordance with the present invention, the dual-position lock includes a mounting shaft assembly. A first retaining member, having a retaining tab disposed on one end, is rotatably mounted on the maintaining shaft assembly adjacent to a cage slide path within the rack so that the retaining tab moves between a first position within the cage slide path for maintaining a cage within a rack, and a second position away from the cage slide path. A second retaining member, having a retaining tab disposed on one end, is rotatably mounted on the mounting shaft assembly so that the retaining tab "moves between a third position within the cage slide path for maintaining a different sized cage within the rack, and a fourth position away from the cage slide path. The first retaining member and second retaining member are selectively engabeable between a first orientation where rotation of the first retaining tab into the first position rotates the second retaining tab into the third position and a second orientation in which rotation of the first retaining tab into the first position rotates the second retaining tab into the fourth position.

Accordingly, it is an object of the present invention to provide a dual-position lock which is significantly easier to lock/unlock than prior art dual-position locks.

Another object of the present invention is to provide a dual-position lock which is significantly easier to adapt to different cages sizes than prior art dual-position locks.

A further object of the invention is to provide a dualposition lock in which it is simple to visually determine whether the lock is in the locked or unlocked position without having to carefully observe the lock.

S Yet another object of the invention is provide a lock having built-in rotational stops to stop rotation of a lock in the unlocked position or the locked position for a simple operation of the lock.

p Still other objects and advantages of the invention will in "i part be obvious and will in part be apparent from the specification.

The invention accordingly comprises the features of construction, combination of elements, and arrangement of parts which will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS For a fuller understanding of the invention, reference is had to the following description taken in connection with the accompanying drawings, in which: FIG. 1 is a perspective view of a dual-position lock of the present invention in the unlocked position for a small cage; FIG. 2 is a perspective view of a dual-position lock of the present invention in the locked position for a small cage; FIG. 3 is a perspective view of a dual-position lock of the present invention in the unlocked position for a large cage; FIG. 4 is a perspective view of a dual-position lock of the present invention in the locked position for a large cage; FIG. 5 is a perspective view of the small cage retaining member constructed in accordance with the present invention; FIG. 6 is a front elevational view of a small cage retaining member constructed in accordance with the invention; FIG. 7 is a perspective view of a large cage retaining member constructed in accordance with the invention; and FIG. 8 is a front elevational view of a large cage retaining member constructed in accordance with the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Referring first to FIG. 1, there is shown a dual-position lock 20 made in accordance with the present invention. Dualposition lock 20 includes a bracket 1, preferably made of stainless steel, and a shaft 13 extending therefrom. One end of shaft 13 is fixed to bracket 1 while the other end of shaft 13 is secured to the rack system adjacent a cage slide path within a known rack (not shown). Bracket 1 is formed with a shoulder 12.

The dual-position lock 20 includes a first retaining member 3 for retaining a large cage within the rack and a second retaining member 9 for retaining a small sized cage within the rack. Reference is now also made to FIGS. 7 and 8 in which a first retaining member 3 having a bore 30 extending therethrough is provided. Bore 30 is dimensioned to receive shaft 13. A first retaining tab 35 is formed on a first end of first retainer member 3. A rotation tab 37 is disposed on retaining tab 35 for facilitating movement of first retaining member 3 about shaft 13.

Teeth 33, separated by lands 39, are formed on a second end of first retaining member 3. A stopping surface 40 is formed at the second end of first retaining member 30 and is disposed between g S bore 30 and teeth 33. Stopping surface 40 is coaxial with bore 30 and extends beyond teeth 33. First retaining member 3 may be go molded as an integral piece.

Reference is now made to FIGS. 5 and 6 wherein a second S retaining member 9 for retaining small size cages within a rack S is provided. Second retaining member 9 has a bore 90 extending therethrough. Bore 90 is dimensioned to receive shaft 13. A retaining tab 92 is formed at a first end of second retaining member 9 while teeth 96 separated by lands 94 are formed from the opposed end of member 9. A stopping surface 98 is formed at the second end of second retaining member 9 and is disposed between bore 90 and teeth 96. Stopping surface 98 extends coaxially with bore 90 beyond teeth 96. Teeth 96 are dimensioned to be received between teeth 33 of first retaining member 3 and are spaced apart a distance to receive respective teeth 33 of first retaining member 3 so as to be in a mated locking orientation. Second retaining member 9 may be molded as an integral piece.

The preferred embodiment bracket 1 is formed with a shoulder 12. A nut orother type of retaining member 16 is provided on shaft 13. Retaining members 3 and 9 are rotatably mounted about shaft 13, shaft 13 passing through bores 30,90. Retaining members 3 and 9 are disposed in facing relationships so that respective teeth 33,94 are in facing relationship with each other. Spring 15 disposed between nut 16 and second retaining member 9 biases second retaining member 9 towards first retaining member 3 in a teeth engaged mating relationship.

eo First retaining member 3 and second retaining member 9 are formed from a rigid wear resistant material, such as polycarbonate in a preferred embodiment. In the preferred embodiment, first retaining member 3 is of a bright and S noticeable color, for example yellow, that is different than the color of bracket 1, so that it is readily apparent, without careful observation, whether first retaining member 3 is in the locked or unlocked position.

Referring now to FIGS. 1-4, operation of the dual-position lock will be illustrated. FIGS. 1 and FIG. 2 illustrate the configuration of lock 20 for locking a small sized cage within the rack. In this configuration, first retaining member 3 is matingly engaged with second retaining member 9 so that retaining tab 35 of first retaining member 3 is aligned with retaining tab 92 of second retaining member 9. To move to the unlocked position (FIG. rotation tab 37 is rotated towards bracket 1 so that rotation tab 37 passes shoulder 12 and first retaining member 3 rotates therewith so that the retaining tab 35 is parallel with bracket 1. Tab 37 is rotated until retaining tab contacts bracket 1 which acts as a stop. In this position, first retaining member 3 is substantially hidden from view by bracket 1 indicating that lock 20 is in the unlocked position.

Because second retaining member 9 is biased to engagingly mate with first retaining member 3, retaining tab 92 is rotated along with tab 35 to a position not within the slide path of the cage thereby enabling the cage to be slid out of the rack. In the S locked position, rotation tab 37 is moved across shoulder 12 away from bracket (FIG. 2) rotating first retaining member 3 away from bracket 1 until rotation tab 37 is along the base of e shoulder 12, stopping rotation. Because second retaining member oe or 9 is biased to engagingly mate with first retaining member 3, S retaining tab 92 on second retaining member 9 is rotated into a position within the slide path of the cage to lock a small sized cage in the rack system. In this position, retaining tab 35 of first retaining member 3 is in plain view indicating that lock is in the locked position.

Reference is now made to FIGS. 3 and 4 which illustrate operation of lock 20 for locking a larger sized cage within a rack. First retaining member 3 is separated from second retaining member 9 and rotated relative to retaining member to orient tabs 92,35 so that when retaining tab 35 is within the cage slide path, retaining tab 92 is not. In a preferred embodiment, first retaining member 3 is rotated relative to orient tabs 92,35 in a second orientation to be matingly engaged wfth second retaining member 9 so that retaining tab 35 of first retaining member 3 is substantially perpendicular to retaining tab 92 of second retaining member 9. In the unlocked position, first retaining member 3 is rotated so that the retaining tab is parallel with bracket 1, as shown in FIG. 3. In this position, first retaining member 3 is substantially hidden from view by bracket 1 indicating that lock 20 is in the unlocked position.

40 In the locked position, first retaining member 3 is rotated by pushing rotation tab 37 away from bracket 1 so that retaining tab S: 35 on first retaining member 3 is positioned within the slide

V.

S: path of the cage to lock a larger sized cage in the rack, as S shown in FIG. 4. In this position, retaining tab 35 of first S retaining member 3 is in plain view indicating that lock 20 is in the locked position.

In a preferred embodiment stopping surfaces 40,98 are dimensioned and positioned to contact each other when rotated into facing relationship. Because stopping surfaces 40,98 extend towards each other beyond adjacent teeth 33,98 respectively, when in facing relationship they prevent mating of teeth 33,96. As a result, the angles at which tabs 92 and 35 are oriented relative to each other can be set and angles which make the lock inoperative can be prevented.

It will thus be seen that the objects set forth above, and those made apparent from the preceding description, are efficiently attained and, because certain changes may be made in the above construction without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all the generic and specific features of the invention herein described, and all statements of the scope of

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the invention which, as a matter of language, might be said to fall therebetween.

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Claims

1. A dual-position lock for locking cages of different sizes within a cage and rack system, comprising: a mounting shaft assembly; a first retaining member rotatably mounted on the mounting shaft assembly having a first end and a second end; a first retaining tab disposed on said first end of said first retaining member and rotatable between a first position within the cage slide path for maintaining a cage within a rack and a second position away from the cage slide path; a second retaining member having a first end and a second end; a second retaining tab disposed on said first end of said second retaining member and rotatable between a third position within the cage slide path for maintaining a different sized cage within the rack and a fourth Sposition away from the cage slide path; Sthe first retaining member and the second retaining member being selectively engagable between a first orientation in which rotation of said first retaining tab into said first position Srotates said second retaining tab into said third position and at Sleast a second orientation in which rotation of said first retaining tab into said first position rotates said second .retaining tab into said fourth position.

2. The dual-position lock in claim 1 wherein said mounting S shaft assembly further comprises: a bracket having a shoulder, said first retaining tab being disposed behind said bracket when in said second position; and a shaft having a first end and a second end, said first end being fixed to the bracket and said second end securing said mounting shaft assembly to the rack.

3. The dual-position lock in claim 2 wherein the first retaining member further comprises: first engagement teeth formed on said second end; a bore therethrough for receiving said mounting shaft assembly; and wherein the second retaining member further comprises: second engagement teeth formed on said second end so as to be selectively meshingly engagable with said first engagement teeth of said first retaining member so that said first retaining member and said second retaining member rotate in unison; a bore therethrough for receiving said mounting shaft assembly.

4. The dual-position lock in claim 2 wherein said first retaining member is positioned on said shaft adjacent said bracket and a rotating tab is disposed on said first retaining tab of said first retaining member.

5. The dual-position lock in claim 1 further comprising: a biasing retaining member disposed on said mounting shaft assembly; and a biasing member disposed between the biasing retaining member and the second retaining member for biasing said second -12- retaining member into engagement with said first retaining member.

6. The dual-position lock in claim 2 wherein said first retaining tab is of a different color than said bracket so that said retaining tab is readily visible when said retaining tab is in said first position.

7. The dual position lock in claim 1 wherein said first retaining member and said second retaining member are molded from rigid wear resistant material.

8. The dual position lock in claim 6 wherein the rigid wear resistant material is polycarbonate.

9. The dual position lock in claim 3 wherein said first retaining member further comprises: a first stopping surface disposed between said bore and said first engagement teeth, said first stopping surface coaxial with *ooo bore; and wherein said second retaining member further comprises; a second stopping surface disposed between said bore and said second engagement teeth; said second stopping surface coaxial with bore; said second stopping surface mating with said first stopping surface to prevent orientation of said first e• retaining member and said second retaining tab of said second retaining member in at least one predetermined position. A dual position lock for locking cages at different sizes within a cage and rack system, comprising: a mounting shaft assembly; a first retaining member rotatably mounted on the mounting shaft assembly having a first and a second end; a first retaining tab disposed on said first end of said first retaining member and rotatable between a first position within the cage slide path for maintaining a cage within a rack and a second position away from the cage slide path; a second retaining member having a first end and a second end; a second retaining tab disposed on said first end of said second retaining member and rotatable between a third position within the cage slide path for maintaining a different size cage within a rack and fourth a position away from the cage slide path; said first retaining member and said second retaining member being selectively enagagable between a first orientation and in which rotation of said first retaining tab into said first position rotates said second retaining tab into said third :position and at least a second orientation in which rotation of So:: said first retaining tab into said first position rotates said second retaining position into said fourth position; said mounting shaft assembly having a bracket with a shoulder, said first retaining tab being disposed behind said bracket within said second position; and a shaft having a first S.end and a second end, said first end being fixed to the bracket and said second end securing said mounting shaft assembly to the rack; -14- said first retaining member further comprising first engagement teeth formed on said second end; a bore therethrough for receiving said mounting shaft assembly; and a first stopping surface disposed between said bore and said first engagement teeth, said first stopping surface coaxial with bore; said second retaining member further comprising second engagement teeth formed on said second end so as to be selectively meshingly engageable with said first engagement teeth of said first retaining member so that said first retaining member and said second retaining member rotate in unison; a bore therethrough for receiving said mounting shaft assembly; and a second stopping surface disposed between said bore and said second engagement teeth, said second stopping surface coaxial with bore said stopping surface mating with said first stopping surface to prevent orientation in at least one predetermined .position; a biasing retaining member disposed on said mounting shaft assembly; *and a biasing member disposed between the biasing retaining member and the second retaining member for biasing said second retaining member into engagement with said first retaining e• member. S 11. A dual-position lock substantially as hereinbefore described with reference to the accompanying drawings. DATED this seventh day of December 1998. LAB PRODUCTS, INC., by their Patent Attorneys, FISHER ADAMS KELLY.