Bench folding leg and brace structure

Information

  • Patent Grant
  • 6173660
  • Patent Number
    6,173,660
  • Date Filed
    Friday, July 2, 1999
    25 years ago
  • Date Issued
    Tuesday, January 16, 2001
    24 years ago
Abstract
A retrofit kit formed by pairs of telescoping legs and a tool anchoring platform for a collapsible leg structure for a metal bench including a T-shaped brace rod having one end of its stem pivotally connected to the underside of the bench and its other end extending between and lockingly engaged with the depending end portion of a pair of the legs. A strut, pivotally connected with the stem of the brace rod, is slidably engaged with a track bracket secured to the undersurface of the bench to limit downward movement of the brace rod with respect to the bench. Links connecting the legs to the strut collapse the legs to a folded position under the bench when the brace rod is manually released from the legs and moved toward the undersurface of the bench.
Description




CROSS REFERENCE TO RELATED APPLICATIONS




Not applicable.




STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT




Not applicable.




BACKGROUND OF THE INVENTION




The present invention relates to a metallic work bench folding leg and brace structure and more particularly to improved telescoping leg adjustment means and a tool mounting platform for such a bench structure.




1. Field of the Invention




2. Description of the Prior Art




The most pertinent patent is believed to be U.S. Pat. No. 4,191,111 issued Mar. 4, 1980 to me for Bench Folding Leg And Brace Structure. This patent discloses an elongated work bench normally supported by a downwardly diverging leg structure connected with a leg folding members. The leg folding members are pivotally connected with the undersurface of the work bench for pivoting the legs to a parallel stored position adjacent the undersurface of the work bench when not in use.




U.S. Pat. No. 3,469,870 issued Sep. 30, 1969 to Barcus for Telescopic Structure With Rotatable Shaft and U.S. Pat. No. 3,724,885 issued Apr. 3, 1973 to Becker for Locking Device For Extendible Tubes are believed good examples of the further state-of-the-art for telescoping tube or leg structure.




This invention is distinctive over the above named patents by providing improved telescoping retrofitting leg assemblies for increasing the operational height of the modified bench with the legs telescopically extended to a maximum height without increasing the bench minimum height with the legs telescopically collapsed. The present disclosure provides an improved leg fixed position adjustment means which is smoother operating, more positive, easier to manufacture and field replaceable. Also, this invention is distinctive over the above named patents by including a platform removably secured in overlying relation on the bench top surface for quickly mounting and supporting tools or equipment such as a power miter box saw, a table top, or the like.




BRIEF SUMMARY OF THE INVENTION




An elongated bench top of substantially channel shape in transverse section is provided adjacent its respective under-surface end portions with a leg bracket for pivotal connection with the upper end of a pair of legs in a manner permitting the legs to diverge downward, laterally and longitudinally of the bench when erected and to lie in parallel relation against the undersurface of the bench between the legs of the channel shape when folded. A T-shaped brace rod pivotally connected by its stem end to the undersurface of the bench has its bar end cooperating with lock pins to form a rigid connection with a depending end portion of the respective pair of legs when erected. A strut pivotally connected with the stem of the brace rod and slidably engaging a track bracket secured to the undersurface of the bench limits pivoting movement of the brace rod away from the bench. Leg folding links extending between and pivotally connecting the respective legs with the strut pivot the legs toward an erected or collapsed position by movement of the T bar end portion of the brace rod toward and away from the undersurface of the bench. Each leg is provided with a telescoping leg extension for elevating the bench. However, the leg length of the inner leg extension in the prior art bench is appreciably less than the length of the bench connected outer leg for the reason a lug on each leg adjacent its leg bracket connected end, is connected with a respective end of each of the folding links and extends through the wall of the outer leg and limits telescopic insertion of the inner leg extension into the outer or surrounding leg beyond the position of the lug. Accordingly, described is a retrofit package of an improved telescoping leg assembly which includes an inner extension leg of only nominally shorter length than the outer or surrounding leg and other improved operating features.




The principal object of this invention is to provide a retrofit package for an existing work bench which comprises pairs of extended range telescoping legs for disposing the bench top at a higher level, and providing a tool, equipment, or table supporting platform removably secured to the upper surface of the work bench by quick connect and release latches and to provide an improved means for adjusting the telescoping legs so that the bench top may be raised and lowered more easily.











BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS





FIG. 1

is a perspective view of a prior art bench in leg erected position, illustrating by dotted lines, the telescopic leg extensions in extended position;





FIG. 2

is a fragmentary vertical cross section of the prior art, to a larger scale, taken substantially along the line


2





2


of

FIG. 1

;





FIG. 3

is a similar perspective view of the work bench having the improved legs and illustrating, in exploded relation, a tool mounting platform;





FIG. 4

is a vertical cross sectional view, to a larger scale partially in elevation, taken substantially along the line


4





4


of

FIG. 3

;





FIG. 5

is a fragmentary exploded perspective view, to a further enlarged scale, illustrating the improved telescopic extension leg assembly;





FIG. 6

is a transverse cross sectional view, to an enlarged scale, taken substantially along the line


6





6


of

FIG. 5

;





FIG. 7

is a longitudinal sectional view, to a different scale, taken substantially along the line


7





7


of

FIG. 5

;





FIG. 8

is a fragmentary side elevational view, on an enlarged scale, of the improved leg lock collar on the depending end portion of the outer telescoping leg;





FIG. 9

is a right end elevational view of

FIG. 8

;





FIG. 10

is a top view of

FIG. 8

;





FIG. 11

is a vertical cross sectional view taken substantially along the line


11





11


of FIG.


8


and illustrating by dotted lines the relative position of the inner telescoping leg;





FIG. 12

is a perspective view of the bench top of

FIG. 3

with the legs removed, illustrating the tool platform sell cured thereto;





FIG. 13

is a fragmentary vertical cross sectional view, to a different scale, taken substantially along the line


13





13


of

FIG. 12

;





FIG. 14

is a fragmentary elevational view looking in the direction of the arrows


14





14


of

FIG. 13

;





FIG. 15

is a bench top view similar to

FIG. 3

, with the legs removed, illustrating another embodiment of a quick connect and release latch;





FIG. 16

is a fragmentary vertical cross sectional view, to larger scale, taken substantially along the line


16





16


of

FIG. 15

;





FIG. 17

is a vertical cross section taken substantially along the lines


17





17


of

FIG. 12

;





FIG. 18

is an exploded isometric view of the area enclosed by the arrows


18


of

FIG. 12

; and,





FIG. 19

is a vertical cross section, to a larger scale taken substantially along the line


19





19


of FIG.


18


.











DETAILED DESCRIPTION OF THE INVENTION




Like characters of reference designate like parts in those figures of the drawings in which they occur.




In the drawings:




Referring more particularly to

FIGS. 1

,


2


and


4


, the reference numeral


10


indicates my prior art bench U.S. Pat. No. 4,191,111 incorporated herein by reference, as a whole, supported by a pair of folding leg and brace structures


12


and


14


. The bench


10


is substantially channel-shaped in transverse section having a horizontal top


16


of uniform thickness having hand grip holes


17


medially its ends and defining a depending surface


18


, parallel depending channel legs


20


and depending end walls


22


. Each of the end walls


22


is provided with a downwardly open slot


23


for the purpose presently apparent.




The brace structures


12


and


14


are substantially identical and in the interest of brevity, only the brace structure


12


is described in detail.




A leg bracket


24


is transversely connected to the bench undersurface


18


adjacent one end portion of the bench. The leg bracket


24


is characterized by two spaced-apart pairs of clevis arms


26


projecting downwardly from the bench undersurface


18


in lateral diverging relation. A pair of tubular wall legs


28


are pivotally connected at their respective upper end portions between the respective pair of clevis arms


26


for pivoting movement toward and away from the bench undersurface


18


. The pair of legs


28


, when erected diverge downward, laterally and longitudinally with respect to the bench top. When folded against the bench undersurface


18


, the legs lie in spaced-apart parallel relation. The depending end portion of each leg


28


is provided with a surrounding fixed position collar


30


. Each of the collars


30


is characterized by a lateral extension


32


having a lock pin


34


secured thereto projecting generally toward the pivotally connected end of the respective leg.




Brace rod means


38


, including a T-shaped brace rod, has one end portion of its stem


40


pivotally connected between the legs of a channel-shaped brace rod bracket


42


longitudinally secured to the bench undersurface


18


between the hand grip holes


17


with the brace rod cross bar


44


disposed transversely of the bench for vertical pivoting movement of the brace rod toward and away from the bench undersurface. The overall length of the brace rod, with respect to the bench, is such that its stem


40


is disposed between the pair of legs


28


and the cross bar


44


of the T-shape such that it will frictionally engage a brace rod latch element


46


, preferably formed from resilient material, such as rubber, having a central downwardly open slot cooperatively aligned with the end wall slot


23


and coextensive with and secured to the outer surface of the respective bench end wall


22


. The respective end portion of the cross bar


44


is provided with an aperture


48


for cooperative reception of the respective lock pin


34


thus locking the legs when in an erected position, as presently explained.




Link and track bracket means


50


interconnects the brace rod means


38


and legs


28


with the bench undersurface


18


. The link and track bracket means


50


comprises an elongated track bracket


52


longitudinally secured to the bench undersurface


18


medially its width and between the leg bracket


24


and brace rod bracket


42


. The track bracket


52


is channel-shaped in transverse section having the depending legs thereof cooperatively slotted transversely, intermediate their ends, as at


54


. The slots


54


are inclined with respect to the bench undersurface


18


and terminate toward the leg bracket


24


in a horizontal plane forming an idler area


56


for the purposes presently explained.




A strut


58


is pivotally connected at one end with the brace rod stem


40


intermediate its ends and is slidably connected at its other end to the track bracket


52


by a pin


60


extending transversely of the track bracket and slidably supported at its end portions within the tracks formed by the bracket slots


54


so that when the legs and brace rod are moved downwardly toward an erected position, as viewed in

FIG. 2

, the end portions of the pin


60


are disposed in the slot idler area


56


thus stopping further downward movement of the brace rod with respect to the bench undersurface. The link means further includes a pair of links


62


which are pivotally connected at one end portion with the end portion of a screw


63


spaced downwardly and projecting inwardly of each leg


28


from its pivotal connection with the clevis bracket


24


and extending through the wall of the upper sleeve end portion of the respective outer bench leg


28


and pivotally connected at their other ends with suitable lug-like brackets


64


secured to opposing sides of the strut


58


intermediate its length. The inward end of the screws


63


thus limit the distance the inner extension legs


70


telescope into the outer legs


28


to that distance between the inward end of the respective screw


63


and the depending end of the respective outer leg


28


.




The links


62


act to pivot the legs


28


downwardly from the bench undersurface


18


when the brace rod


40


is moved downwardly and to stop such leg movement when the pin


60


is disposed in the idler area


56


and the brace rod and legs are disposed in downwardly converging relation thus permitting the brace rod cross bar to be engaged with the collar pins


34


. The pair of links


62


, each comprise a turnbuckle for the purpose of adjusting its length in accordance with the desired spacing between its connection with the respective bench leg and the strut bracket


64


. The pivotal connection


63


, at the respective end of each link of the pair of links


62


, is a ball joint type connector.




In accordance with the present invention and referring also to the remaining figures, an improved telescoping leg assembly (

FIG. 5

) including an outer leg


128


and an inner extension leg


170


having an overall length, including a foot portion


172


, greater than the length of the prior art inner leg length as presently evident, and is configured as a complete leg assembly or package for retrofitting the prior art bench


10


. The upper end portion of the outer leg


128


is pivotally connected with the prior art clevis arms


26


. The wall of the outer leg


128


, adjacent its clevis bracket connected end, is provided with a bore


129


. The leg wall portion diametrically opposite the bore


129


is bulged or struck outward to form a protrusion


131


having a hexagonal nut


133


secured thereto (FIG.


6


).




The inner wall surface


135


of the outer leg


128


permits the inward end of the telescoping leg


170


to slidably extend into the leg


128


until the inner end of the leg


170


abuts the inward end surface


137


of the outer leg wall reinforcing sleeve


139


.




The prior art leg extension lock collar


76


is retrofitted by an in the field replaceable lock collar


176


formed in endless ring fashion from non-metallic material providing a non-galling low friction bearing surface for ease of angular rotation relative to the leg


128


. The lock collar


176


similarly includes diametrically opposite field replaceable inwardly projecting inner leg locking lugs


178


similar to prior art lugs, not shown, in the lock collar


30


which required press fitting in the prior art lock collar. The lugs


178


include a flange end


177


and are secured in the collar


176


by means of an overlying recessed plate and screws


179


(FIG.


10


). The lugs


78


are longitudinally slidable in the extension leg longitudinal grooves


82


(

FIG. 5

) and freely enter one of a series of longitudinally spaced slots


84


extending latterly from one side of the groove


82


to lock the inner leg


170


with the outer leg. The slots


84


are characterized at their juncture with the groove by a lead-in radii on opposite corner edges, as at


187


, for preventing generating burrs on these edges and to insure ease of entry of the lugs


178


. A pair of springs


141


nested by grooves


143


in diametric opposite areas of the lock collar


176


are respectively connected at one end by an end tang with an integral lock collar pin


180


and at the other end with a leg wall tongue


181


fabricated in the wall of leg


128


within a partially surrounding recess


183


for loosely receiving the spring other end tang without the spring tang protruding into the inner space of the leg


128


and interfering with the installation or rotation of the lock collar


176


. The springs


141


normally bias the lugs


178


into selected extension leg lateral slots


84


, as presently explained.




Referring more particularly to FIGS.


12


and


17


-


19


, the step forming bench top side rails


90


are normally held in place by the top and bottom lip elements


92


and


94


of the bench top side rails


20


. The bench top supporting of the side rails


90


is enhanced by a spring clip


200


. One end portion of the spring clip


200


is attached to the side rail


90


medially its end and the other end portion


201


of the spring clip is interposed between the depending surface of the side rail and the lip


94


of the bench side rail


20


in a partial wrap around action of the lower portion of the respective side rail


90


to insure retaining the side rail on the bench top.




The respective hollow end portion of the side rail


90


is preferably closed by an end cap


202


. The end cap is preferably formed from resilient material and is characterized by a planar end wall


204


having a perimeter complimentary with the perimeter of the respective end of the side rail


90


. The end cap further includes an endless side wall


206


which is frictionally received by the inner peripheral wall surface


208


of the side rail


90


. The end cap is further characterized by a plurality of transverse partition walls


210


to maintain the endless wall configuration of the end cap and insure its retention by the respective end portion of the side rails


90


.




The bench retrofit package further includes a support panel


147


(

FIG. 3

) for mounting a tool such as a miter saw, not shown, on the bench top


116


. The panel


147


may be singular or multiple hingedly joined sections, as illustrated by broken lines (FIG.


3


), and generally rectangular in overall configuration and disposed longitudinally on the bench top


116


. Respective end portions of the support panel


147


are bored, as at


151


(FIGS.


12


-


13


), in vertical alignment with cooperating apertures


153


punched through the work bench top. The apertures


153


are characterized by lateral diametrically opposite slots


159


. In the example shown, the bench top apertures


153


are also punched through the prior art track bracket


52


(FIGS.


13


-


14


), between the legs thereof, and form diametrically opposite depending stops


174


(FIG.


14


), for the purpose presently explained. The panel apertures


151


respectively receive quick connect and release latch means


155


for removably joining the panel


147


to the bench


116


.




Referring more particularly to

FIGS. 3

,


12


and


13


, the quick connect and release latch means


155


comprises a cup-like socket


157


having a cylindrical wall portion snugly received by the wall forming the panel aperture


151


and having a centrally bored bottom wall. An outstanding peripheral flange


161


on the cup socket wall overlies the top surface of the panel


147


for securing the socket


157


, as by screws


163


, only one being shown. A cylindrical latch body


165


is angularly rotatably received by the cup socket


157


and includes a threaded stem


167


, having a thread frictional locking element


166


, secured to a latch shaft


169


in turn slidable and angularly rotatably received by the bench top bore


153


. The inward end of the latch body


165


is provided with a downwardly open annular slot adjacent its periphery which receives a compression spring


173


normally biasing the latch body


165


out of the cup socket


157


. The shaft


169


transversely supports, at its depending end portion, a lock pin


171


which cooperatively enters the diametrically opposite slots


159


of the bench top bore


153


for contiguously locking the panel


147


to the bench top when the spring


173


is manually compressed into the cup


157


. The shaft


169


and lock pin


171


are angularly frictionally rotated substantially 95° in one direction, by the latch body


165


, from the position of the opposing slots


159


of the bore


153


. Respective end portions of the lock pin


171


contact the stops


174


for indicating a latch locked position. The latch body


165


is further provided with an arcuate relatively narrow inwardly extending groove


175


which receives a key, for example, a chord of a coin, or the like, for manually collapsing the spring


173


by depressing the latch body and angularly rotating the same and the lock pin


171


in a latch locking or releasing direction.




Referring also to

FIGS. 15 and 16

, an alternative quick connect and release latch means


185


secures the panel


147


to the bench top


116


and comprises a cup-like star shaped, in the example shown, control wheel


186


having a central downwardly directed centrally bored and threaded sleeve


188


, similarly provided with a thread friction locking element


189


, secured and frictionally held to one end portion of a latch shaft


190


vertically slideably received by the bore


153


in the respective end portion of the panel


147


. The depending end portion of the shaft


190


is similarly provided with a transversely disposed latch pin


171


′ which similarly enters the slots


159


of the bench top bores


153


to secure the panel


147


to the bench top


116


when the latch shaft


190


is inserted into bench top bore


153


and angularly rotated substantially 95°, in one direction (preferably a thread engaging direction) after insertion until it stops when latch pin


171


′ contacts the bracket stops


174


. When not engaged with the bench top


116


the latch pin


171


′ is normally nested by a slot


196


in the depending surface of the respective end portion of the panel


147


. Resilient means such as a helical expansion spring


194


axially surrounds the star wheel sleeve


188


and is interposed between the depending surface of the control wheel and the adjacent surface of the panel


147


to bias the latch pin


171


′ against the depending surface of the bench top


116


when the latch means


185


is in connected position with respect to the bench top which is accomplished by manually depressing the control wheel


186


and spring


194


to similarly engage the stops


174


. With the latch pin


171


′ in contact with the stops


174


, the control wheel


186


may be manually further threadedly engaged with the shaft


190


until the spring


194


is substantially collapsed and the depending end of the sleeve


188


contacts the surface of the panel


147


, thus immobilizing the spring release feature of the latch means


185


.




Obviously the invention is susceptible to changes or alterations without defeating its practicability. Therefore, I do not wish to be confined to the preferred embodiments shown in the drawings and described herein.



Claims
  • 1. In combination with a metal bench having opposing ends, an undersurface, bench leg bracket means secured to the undersurface of each end portion of said bench top, a bench brace rod at respective end portions of the bench undersurface and having opposing end portions projecting longitudinally of the bench medially the bench width and having one end portion of each rod pivotally connected with a medial portion of the undersurface for vertical pivoting movement of each rod other end portion toward and away from said undersurface, said other end portion of said brace rod having a transverse cross bar provided with a lock pin receiving aperture at respective ends of the cross bar, said metal bench comprising:pairs of inner and outer telescoping tubular wall bench legs having upper and lower end portions pivotally connected by the respective upper end portion of each outer bench leg of said pairs of bench legs to said bench leg bracket means on transversely aligned inclined axes for disposing the longitudinal axes of each pair of said pairs of telescoping bench legs when erected in downward lateral and longitudinal diverging relation relative to said bench top, the tubular wall of each outer leg of each pair of said pairs of legs having a connector supporting protrusion adjacent said pivotally connected upper end portion permitting unobstructed inward telescopic movement of the upper end portion of the respective inner leg beyond the position of the wall protrusion, each inner leg of each pair of said pairs of bench legs having a foot forming extension axially depending from its lower end portion; and, link and track bracket means pivotally connecting an intermediate portion of each said brace rod with said wall protrusion on the respective outer leg of each pair of said pairs of bench legs for pivoting movement of said pairs of bench legs from a bench erected position to a parallel stored position adjacent said undersurface and vice versa by vertical movement of said bench brace rod.
  • 2. The combination according to claim 1 and further including:a nut secured to the wall protrusion for connection with said link means of said link and track bracket means.
  • 3. The combination according to claim 2 in which said each said inner leg is coextensively provided with diametrically opposite groves, each groove having diametrically opposite series of longitudinally spaced inner leg slots projecting laterally from one side of each groove, and further including:each said outer leg of said pairs of legs having diametrically opposite slots in its end portion adjacent said foot; and, field replaceable inner leg locking collar means rotatably surrounding each said outer leg in overlying relation with respect to the outer leg diametrically opposite slots.
  • 4. The combination according to claim 3 in which the edges of the inner leg lateral slots at the juncture with the inner leg groove are provided with a radius for ease of accepting the collar locking lugs.
  • 5. The combination according to claim 3 in which the locking collar means includes:a collar having diametrically opposite circumferentially extending through slots; a pair of diametrically opposite inner leg locking lugs projecting through said collar for normally maintaining the respective pair of legs in a selected telescopic position; and, resilient means longitudinally disposed, within the respective collar slot and connected at respective ends with the collar and the outer leg for normally biasing said collar locking lugs in an inner leg locking lug slot entering direction.
  • 6. The combination according to claim 5 in which the sides of said bench top are channel shaped having upper and lower horizontal parallel channel legs supporting a bench step side rail, and further including:an elongated spring clip means secured by one end portion to said side rail and interposed at its other end portion between said side rail and the lowermost said channel leg.
  • 7. The combination according to claim 6 in which the bench step further includes:a resilient end cap on the respective end of said bench side rail.
  • 8. The combination according to claim 5 in which said bench top is provided with longitudinally spaced through apertures, and further including;a tool supporting panel longitudinally overlying said bench top and having through apertures in registration with the bench top apertures; and, quick connect and release latch means for anchoring said panel on said bench top.
  • 9. The combination according to claim 8 in which the latch means includes:a shaft rotatably projecting through the panel and bench top apertures; a latch pin transversely extending through the shaft adjacent the bench undersurface; a shaft control member threadedly and frictionally secured to the other end portion of said shaft; a latch pin stop secured to the bench top undersurface for limiting angular rotation of the shaft; and, a resilient member biasing said latch pin toward the undersurface of said bench top.
  • 10. The combination according to claim 9 in which the latch means includes:a cylindrical wall having a centrally apertured end wall for forming a socket axially nested by each panel aperture; a latch body having an axial stem angularly rotatable in the socket; an internally threaded sleeve having one end threadedly and frictionally secured to the latch body stem and projecting through the bench top aperture; a second latch pin extending through the other end portion of the sleeve; and, a resilient member axially biasing the second latch pin toward the undersurface of the socket.
  • 11. The combination according to claim 1 in which opposite sides of the bench top removably support a bench step between upper and lower bench top channel legs and further including;a spring clip having a first end portion secured to said bench step intermediate its ends, said clip having a second end portion normally interposed between the bench step and one said channel leg.
  • 12. A work bench having a bench top provided with longitudinally spaced through apertures, comprising;a tool supporting panel longitudinally overlying said bench top and having through apertures in registration with the bench top apertures; quick connect and release latch means for anchoring said panel on said bench tops said latch means including a shaft rotatably projecting through the panel and bench top apertures; and, a latch Pin transversely extending through the shaft adjacent the bench undersurface.
  • 13. A work bench having a bench top provided with longitudinally spaced through apertures, comprising:a tool supporting panel longitudinally overlying said bench top and having through apertures in registration with the bench top apertures: quick connect and release latch means for anchoring said panel on said bench top, said latch means including: a shaft rotatably projecting through the panel and bench top apertures; a latch pin transversely extending through the shaft adjacent the bench undersurface; a shaft control member threadedly and frictionally secured to the other end portion of said shaft; a latch pin stop secured to the bench top undersurface for limiting angular rotation of the shaft; and, a resilient member biasing said latch pin toward the under-surface of said bench top.
  • 14. The combination according to claim 13 in which the latch means includes:a cylindrical wall having a centrally apertured end wall for forming a socket axially nested by each panel aperture; a latch body having an axial stem angularly rotatable in the socket; an internally threaded sleeve having one end threadedly and frictionally secured to the latch body stem and projecting through the bench top aperture; a second latch pin extending through the other end portion of the sleeve; and, a resilient member axially biasing the second latch pin toward the undersurface of the socket.
  • 15. The combination according to claim 13 in which the panel is transversely divided defining panel end portions and further including:a hinge joining the panel end portions; and, latch means for anchoring said platform to the bench top.
US Referenced Citations (8)
Number Name Date Kind
3469870 Barkus Sep 1969
3724885 Becker Apr 1973
3777675 Hanusiak Dec 1973
4186784 Stone Feb 1980
4191111 Emmert Mar 1980
4715296 Wilkinson Dec 1987
4864941 Goulter Sep 1989
4949649 Terres et al. Aug 1990
Foreign Referenced Citations (1)
Number Date Country
250321 Mar 1964 AU