US2555838A

US2555838A - Traveling platform conveyer

Info

Publication number: US2555838A
Application number: US724372A
Authority: US
Inventors: Furman S Abbott
Original assignee: Individual
Current assignee: Individual
Priority date: 1947-01-25
Filing date: 1947-01-25
Publication date: 1951-06-05
Anticipated expiration: 1968-06-05

Description

June 5, 1951 F. S. ABBOTT TRAVELING PLATFORM CONVEYER 1 .Q ,mw NY Ilm. nl m mm um MMmw MN@ Q 3 a, k NSN ww. MM Mm Z a E. T ww Mw A, N @ym June 5, 1951 F. s. ABBOTT TRAVELING PLATFORM coNvEYER 3 Sheets-Sheet 2 Filed Jan. 25, 1947 June 5, 1951 F. s. ABBOTT TRAVELING PLATFORM CONVEYER 5 Sheets-Sheet 5 Filed Jan. 25, 1947 IN1/ENT.

Patented June 5, 1951 UNITED STATES PATENT OFFICE y.

TRAVELING PLATFORM CONVEYER Furman S. Abbott, Montclair, N. J. Application January 25, 1947, Serial No. 724,372

6 Claims. l

The present invention relates to conveyors of the type disclosed in the Bausman et al. Patent No. 1,023,103 of April 9, 1912, which is particularly adapted to move a plurality of successively arranged platforms in two lateral banks.

The general object of the present invention is to provide such a conveyor which is characterized by a plurality of successively arranged platforms disposed in two laterally extending banks and simultaneously movable rst along one level,:then across to another level, along the second level and finally back to the first level, in which means are provided for effective support of both ends of each platform substantially at all times during its travel and in any position whereby the ,apparatus is efliciently adapted to automobileor car storage, in parking lots, and in buildings and the like.

A more specific object of the invention is to provide such conveyor apparatus wherein the successively arranged platforms are so supported at all times during transport and in all positions as to make the device efliciently useful in the support and handling of very heavy objects, such as automobiles, and which, for this purpose, is characterized by separate track-riding means mounted on opposite ends of each platform with separate transfer track means at both ends of the apparatus respectively to cooperate with the separate track-riding means to assure eiiicient support and guidance in transfer of the platforms from lateral track means Vat one level to lateral track means at another level.

Another object of the present invention is to provide in such conveyor apparatus certain switch means effectively permitting the employment of dual transfer track means at both ends of the apparatus for continuoussupport and guidance of the platform-supporting track-riding means at both ends of each of the platforms, `while effectively permitting those at the same ends of each platform to follow one path, and those at the `other ends of the platform to follow another path with continuous support of bothY sets of track-riding means.

Still another object of the present invention is the provision in such conveyor apparatus of certain transfer track means which efficiently accomplishes the continuous platform support and elfective guidance desired.

A further object of the present invention is to provide for such a conveyor device unique switch means `adapted to the structures of different embodiments whereby the desired operation may be effectively accomplished.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

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.

For a fuller understanding of the nature and objects of the invention, reference shouldlce had to the following detailed description taken in connection with the accompanying drawings, in which:

Fig. l is a longitudinal elevational section of one embodiment of the conveyor apparatus of the present invention showing the mechanism thereof mounted in proper position with respect to a ground line diagrammatically indicated and above which the entire structure is mounted;`

Fig. 2 is an enlarged top-plan view, with parts brokenaway and omitted, of the apparatus shown in Fig. 1;

Fig. 3 is a longitudinal elevationalsection, with parts brokenlaway and omitted, showing one end of a modified form of the apparatus depicted in Fig. 1 as adapted for mounting below the ground line in a recess, the adjacent soilbeing diagrammatically indicated;

Fig. 4 is a top-plan view, with parts broken away and omitted, of a further modification of the apparatus shown in Fig. l;

Fig. 5 is a transverse elevational sectionof the apparatus, with parts broken away, shown in Fig. 4, taken substantially on line 5-5 of Fig. 7, wherein a longitudinal elevational section is shown;

Fig. 6 is a transverse elevational section, with parts broken away and in section, taken substantially on line 6 6 of Fig. 7;

Fig. 7 is a longitudinal elevational section, withparts broken away, of the apparatus shown in Figs. 4.-, 5 and 6; and

Fig. 8 is a sectional view taken substantially on line 8M@ of Fig. 7, showing more of the track structure than that indicated in the left-hand half of Fig. 7.

In the drawings, similar numerals identify similar parts throughout and as will be noted from Figs. 1 and 2, an embodiment of an apparatus of the present invention may comprise an upper laterally extending track means le and a lower laterally extending track means I l. Each of the track means It! and II may comprise a pair of transversely spaced apart railssuch as I2, I2 and I3, I3 respectively, as may be desired.

Track means IQ and II are adapted to guide and '1 support therefrom a plurality of platforms Ill-I4 each suspended from track-riding or rail-riding means I5 and i. Accordingly, due to the suspension support of the platforms Ill-lil, the upper and lower lateral track means Il] and II are mounted in elevated positions above the ground line indicated diagrammatically at I'I, as shown in Fig. 1, with the suspended platforms I-Ili in the lower bank adapted to be located successively at a receiving station, such as at I8, indicated at the left-hand end of the apparatus and shown in Fig. l near the ground surface so as to permit an automobile to be driven onto each platform.

Each platform I4 preferably comprises a pair of transversely spaced apart channel members I9, I5 as shown in Fig. 2 which are adapted to receive the four wheels of an automobile. Each channel member I9 is supported in the vicinity of its Vends from one each of the trackriding means I5 and I6 by any suitable means such as suspension members or cables 2li-2S, Preferably, in the embodiments shown in Figs. l and 2, the track-riding means I5 and I6 are of similar construction and each may be in the form of a truck. The rail-riding means I5 comprises a transverse axle 2I supporting the cables 2G-2I3 connected to platform members I3, I9, with

wheels

22, 22 rotatably mounted thereon to ride upon the rails I2, I2 and I3, i3. The rail-riding means I6 comprises a transverse axle 23 to which cables -2!) are connected for support of the other end of the channel members I9, i9, and

similar wheels

22, 22 are mounted thereon with the ends of that axle extending beyond those wheels to carry anchoring clamps 2d, 2d. Thus the rail-riding means I5-I5 constitute one set thereof and the rail-riding means IIS-I5 constitute another set thereof with the latter provided with clamps 24-24 to fasten them to any suitable flexible endless means, such as a pair of

endless cables

25, 25. As a result

endless cables

25, 25 will carry around with them the set of rail-riding means Iii-I6 and in certain positions, as hereafter explained, will support those rail-riding means. means I5--I5 are -unconnected to the

cables

25, 25.

A pair of pulley wheels 25, 2S are rotatably supported on the vleft-'hand end of the apparatus as shown in Figs. l and 2, and a similar pair 2l, 2'! are rotatably supported at the right hand end of the apparatus with the

endless cables

25, 25 trained about those pulley wheels. At least one of those pulley wheels, such as the one at 25, shown in Fig. l, and in the upper left'- hand corner of Fig. 2, is driven by any suitable means such asY a sprocket 28 and .driving chain 29. The sprocket 28 may be iixed upon shaft 3@ rotatably mounted through bearing support 3| with its inner end xedly carrying the pulley wheel 26. The other pulley wheel 26 may, if de sired, be driven in similar manner. Similar supporting bearings 3l-3I carry the stub shafts for the remaining pulley wheel 2E and the two pulley wheels 2l, 27..

The driven shaft 3e also carries a sprocket 32 fixed thereto about which is trained a driving chain 33, in turn trained about another sprocket 34 fixed to a stub shaft 35 carried by a supporting bearing 35, and this structure is preferably duplicated at both ends of the apparatus and on both sides thereof, as shown in Fig. 2.

The other set of rail-

riding Stub shafts

35, 35, at either end of the apparatus, have Y lll xed thereto arms 31, 3l adapted to engage beyond and behind the transverse axle 2l of each rail-riding means I5, so as to lift the latter at the left-hand end of the apparatus and lower it at the right-hand end of the apparatus at substantially the same speed as the rail-riding means I6 of the same platform I4 is lifted and lowered between the upper and lower lateral track means I and II. Of course, for this purpose, other endless means similar to the

cables

25, 25 to which transverse axles 22-23 are anchored. may be employed in lieu of the operating arms 32h-3l and their driving mechanisms. Such means may comprise endless chains and in such case the

wheels

26, 25 and 2l, 2'! will be sprockets.

t each end of the apparatus shown in Figs. 1 and 2 are provided two inner and outer transfer track means, respectively to guide and support the sets of rail-riding means i5-l5 and I-I as the latter are transferred between the upper and lower lateral track means I!) and I l. At the left-hand end of the apparatusthe outer transfer track means 33 may comprise upwardly sloped

continuations

39, 39 of vthe lower rails I3, I3 with those continuations preferably being upwardly curved and extending at least to the vicinity of the mid-plane of the apparatus which passes through the axes of the stub shafts '3Q-35 and 35-35 Downwardly'sloped (preferably curved) continuations lle, 4G of the left-handi ends of the upper rails I2, I2 extend also to the vicinity of that mid-plane and are spaced inwardly from the upwardly

curved extensions

39, 39 preferably a distance a little greater than the diameter cf the

wheels

22, 22 carried by each of the transverse axles 23-23 of the rail-riding means I-I. rihis transfer track means 38 is preferably duplicated on the right-hand end of the apparatus with the downwardly curved extensions 42, 9 spaced inwardly of the upwardly curved extensions 39, 39 a distance slightly greater than the diameters of the wheels 22--22 mounted on the transverse axles 2I--2I of the rail-riding means Iii-I5. It will be noted from Fig. 1 that the extensions 39-39 and lil-4l@ of the transfer track means 38, 28 lie along arcs of circles generated about the axes of the stub shafts 3@ and 35 at the left and right ends of the apparatus.

Each of the two inner transfer track means at iii, 4I comprises downwardly sloped, preferably curved extensions 6.2, i2 of certain portions of the upper railsV I2, i2 with the one at the lefthand end lying along the arc of a circle generated about the axis of stub shaft 35 and the one at the right-hand end lying along the arc of a circle generated about the axis of stub shaft 3E. Each of these inner transfer track means li! also includes an upwardly sloped, preferably curved plate i3 and a laterally extending flat plate de fixed together and pivotally mounted at d5 to constitute switch means. The lateral part of each switch means may comprise a section of the upper rail I2 or may be positioned in a notch in the latter, as shown in Fig. 2, so that when swung upwardly as shown at 'the right-hand end of Fig. 1 a gap will be provided in the upper rail. When the switch means is in the closed position, as shown in the left-hand end of Fig. 1, the curved transfer track section A3 thereof will have its lower end located adjacent the lower rail I3. rlhe portion between the lower end of section 43 and a point in the vicinity of the mid-plane lies along the arc of a circle generated about the `axis of the stub shaft 35, with the lower endY of f the downwardly curved extension 42 spaced inv wardly` from that curved transfer track section a `distance which is alittle `-greater than the diameters of the wheels`22-22` xed on transverse axles 2I`2| ofrail-riding means I5-I'5.

In operation of the embodiment of the apparatus shown in Figs. 1 and 2, for the purpose of parkingand storing automobiles, the apparatus may be stopped with the platform I4 located at the approach station i8 in the position shown so that a car may be driven up on the channel numbers I9, I`9 of the platform. Driving means may then be operated to cause the drive chain E9 to drive clockwise the pulley wheel 26 shown at the left in Fig. 1. By virtue of the facts 'that endless cables 25, are tied together by transverse axles 23-23,and thelifting arms Si at the left-hand end of Fig. 1 and the lowering arms 3l, 3l at the right-hand end thereof Vare spectively driven by sprockets 32 and 3ft in turn driven by chains 33-33 from the pulley wheels and i'i. 2i, it will be seen that the endM

less cables

25, 25 will be moved along the upper track means Id down about pulley wheels 2l, 2l back along track means II and up around pulley wheels 2E, 2t carrying therewith the set of rail-riding means Iii-p-IG. Of course the two endless means or cables 25 nay separatciy and positively driven from a common power source, such as by duplicating the drive sprocket 28 and driven chain 29 on both sides of the apparatus, and with the two

chains

29, 29 driven by sprockets xed on a common driven shaft. This motion of the

endless cables

25, 25 causes the successively arranged platforms I 4-Ill to move forward to position another platform It at l the receiving station It. This action may be continued until all of the platforms in the two banks are lled with cars and a driver may readily select his car for removal, although it be in any one of the numerous positions in the apparatus, by operating the latter until the platform supporting his car is moved either to the receiving station i3 or to the opposite end of the apparatus at the ground line, then to be driven off.

Cil

6 Switchsections, 4I4 closethelgaps in the upper rails lf2, I2 so that there willbe continual supe port of the rail-riding`means I 6.

As the platform I4 approaches the right-hand end of theapparatus a now-trailing unconnected rail-riding lmeans I5 of a preceding platform will roll back along lower rails I3, I3 to engage therear sides of the curved sections (it, 413 of the switch 'means at that endto swing `them upwardly to the positions-shown in'Fig. l, thereby permitting free `passage of that unconnected trailing railridingmeans. This, of course, causes the switch sections #liked tube-swung to the liftedvposition shown in Fig. l, after forward passage thereover of the then leading unconnected rail-riding means I5 ofthe platform under discussion, so as to permit the trailing connected rail-riding means I6 of the latter to be carried down the curved extension 112 of the'inner transfer track means at the right-hand end. Eventually, after passage of the trailing unconnected rail-riding means I 5 of the preceding carriage heyondthe curved switch sections '43, i3, the switch will be closed, either by force of gravity or by pressure of the rail-riding mean-s I E of the succeeding platform under discussion against the faces of the curved sections `41%, is vso that that rail-rid ing means will then beguided to the lower tracks E3, It. During this action of course the uncon nected leading rail-riding means I5 travels `first along the downwardly curved extensions et, lil of the transfer track means at the right-hand end of the apparatus, 4and then 'on to the upwardly curved extensionstt, `39 to be guided to the lower rails I3, I 3. During this action the lowering arms QMS? lead the transverse axle 2i to support the rail-riding means I5 and permit it to travel down the right-hand transfer track means at 38 at relatively the same speed as the rail-riding means it is lowered by cables 25, down along the right-hand transfer track means at tI. Thus, it will be seen that at all times there is positive support of the means from which the platforms are suspended.

During such action the rail-riding means I5 at one end of the platform Ill which is supporting a particular car will be caused to move up along the

curved extensions

39, 39 at the left-hand end of the apparatus and will be supported both by those curved extensions and the endless cables E5, 25 to which that rail-riding means is anchored. After rail-riding means I6 is moved up beyond the mid-plane with the

wheels

22, 22 thereof passing between curved extensions 3S and lit, the wheels will' then ride upon the latter to be transferred to the upper rails I2, I2. During this movement of rail-riding means I5 the trailing unconnected rail-riding means I5 will be up the curved section 43 of the switch means, and since the lifting arms 3l, :il travel at substantially the same angular velocity as the angular velocity of the pulley wheels 2t, 2t, those arms will be engaged behind transverse axle 2i of that unconnected rail-riding means and lift the latter at relatively the same speed as connected rail-riding means it li' by the

cables

25, 25. Eventually, the

wheels

22, 22 of the rail-riding means I5 will pass up to roll over the downwardly curved extensions 42, 4?. to be guided to the upper rails I2, I2. Then with continued motion of the

cables

25, 25 the plat-u form I4 will be carried forward along rails I2, I2 now with its'unconnected rail-riding `means i5 leading its connected rail-riding means It.

tlf)

Of course, it is obvious that the apparatus shown in Figs. 1 and 2 may be operated in either direction, since the transfer track means at both ends of the apparatus are similar in structure and functioning; and, of course, suitable equivalents may be substituted for the various elements of the apparatus as desired. For example, either the transverse axles of the track-riding means or the wheels thereof may be employed to operate the switches, or separate means mounted on or to the platforms may be used to perform similar functions. Further, it should be understood that a simple modication of the apparatus can make possible operation thereof without driven means positively to lift and check the lowering of the set of unconnected rail-riding means i5--I5- In such case, the transfer track means may he constructed as substantially straight line ways sloped at suitable angles with the horiaontal, e. g., at 30 to 66.'and with those two transfer track means, along which the endless means or cable for carrying the `set of rail-riding means Iii-I5 are guided, being provided at their upper and lower ends each with two pulley wheels or sprockets somewhat similar to those at 2t and 2l'. In such case, of course, each of the inner transfer track means will be provided with suitable switchesat its top and bottoni alternately to provide for entrance thereto of the rail-riding means of one set, and free passage for the rail riding means of the other set, with the railriding means of the different sets for each platform rigidly connected together by separate frame structure, or by the platform structure itself, as in the case of Fig. 3. Positive drive of the connected rail-riding means by the endless cables .and guidance up the sloped vtransfer track means will cause the unconnected rail-riding means either to be pushed or dragged up, as the case may be, its sloped transfer track means at substantially the same rate of speed, thereby retaining the platform substantially level. At the top of the transfer track means for the unconnected set of rail-riding means a simple switch may be provided in association with `an extension of the transfer track means so that the unconnected rail-riding means may be pushed or pulled up this extension past the switch which may be opened by passage of that rail-riding means, and the switch then closed, such as by force of gravity behind that rail-riding means, so that when the other-rail-riding means is then pulled forward `along the upper track means by the endless cables, the unconnected rail-riding means will be supported by the switch and cross the latter to the upper track means.

The apparatus shown in Figs. 1 and 2 may be modified so that it may be mounted in a recess below the surface of the ground, as proposed in Fig. 3 wherein the ground line is indicated at I'I with a recess 46 provided therebelow. The apparatus to be mounted in the recess 45 is similar in all respects to that shown in Figs. l and 2 except that each channel member i9 of platform I4 is mounted above its rail-riding means I5 and I6, rather than being suspended therefrom by any suitable means, such as by standards lll, 4l'. As a result, each platform I4 as it is moved to the position shown in Fig. 3 is adapted to receive thereon at the ground line Il' a car which may then be carried around for underground storage or parking.

The modified form of the apparatus as shown in Figs. 4 to 8 inclusive differs chiefly from that shown in Figs. 1 and 2 in that separate pairs of transversely spaced rails are provided for the two sets of rail-riding means Iii-I5 and IS-Iii. The pairs of upper rails I2, I2 and lower rails I3, I3 are adapted for support of the connected rail-riding means IG-I which are carried forward by the

endless cables

25, 25 and another pair of upper rails H2, II2 and a second pair of lower rails H3, H3 are located inside the pairs of rails I2, I2 and I3, I3 respectively for support of the unconnected rail-riding means I5-I5.

.lisV shown in Figs. 7 and 8, the lower rails I3, I3 are constructed at the left-hand end of the apparatus, as viewed therein, similarly to their construction in the modication of the apparatus shown in Figs. 1 and 2. The upper rails I2, I2, however, continue straight through past the inner transfer track means I4! at the lefthand end of the apparatus to the inner transfer track means 4I at the right-hand end of the apparatus, terminating in downwardly sloped

extensions

42, 42 as in the case of the apparatus shown in Figs. 1 and 2'. The ends of the lower rails I3, I3 at the right-hand end of the apparatus terminate in the vicinity of the inner transfer track means 4I, where they merge with upwardly curved extensions 48, 48 as shown in Figs. 4 and '7.

In the apparatus shown in Figs. 4 to 8 inclusive, the other pair of lower rails I I3, H3 terminate at the left-hand end of the apparatus in the Vicinity of the inner transfer track means I4I,

Cri

and there a pair of upwardly curved switch plates 43, I43 are provided to receive from the rails I i3, I I3 the

wheels

22, 22 of the unconnected railriding means I5-l5. The switch plates |43, |43 are each pivotally mounted substantially at the mid-plane by suitable supporting structure 49 such as a stub shaft mounted upon a support 5i). The switch plates |43, E43 are positioned relative to the other structure and the downwardly curved ends I42, |42 of the upper rails H2, II2 similar to the arrangement of the sections 43, 43 of the switch means at the inner transfer track means Y4I at the left-hand end of the apparatus shown in Figs. l and 2. Each switch plate M3 is provided with an upwardly extending operating arm 5I, which is laterally off-set from the switch plate to lie above the rail I3 as shown in Figs. 4, 6, 7 and 8, so as to be in the path of wheel 22 of each of the connected rail-riding means I6, as indicated in dotted lines at 52 in Fig. 7.

In the apparatus shown in Figs. 4 to 8 inclusive, continuations of the pair of inside upper rails II2, II2 as indicated at 53, extend to the outer transfer track means I38 at the right-hand end of the apparatus and terminate in downwardly curved extensions I, I4@ similar to extensions 4d, 4I) of the upper rails I2, I2 in the structure of Figs. 1 and 2. The lower pair of rails H3, H3 also terminate at the right-hand end of the apparatus in upwardly curved extensions ISQ, E39 to provide parts of the transfer track means 38 similar to the upwardly

curved extensions

39, 39 of rails I3, I3 at the right-hand end of the apparatus shown in Figs. 1 and 2. A gap is provided in each of the inside upper rails H2 at the inner transfer track means 4l to the left of

sections

53, 53 thereof, and in each of those gaps is pivoted a switch plate I44 on any suitable means, such as a stub shaft I45 suitably 1f supported on fixed structure at 54. Each switch plate I44 is provided with an upwardly extending operating arm l55 off-set therefrom to lie over the rail I2 in the path of wheel 22 of each of the connected rail-riding means I3 and the switch plate |44 cooperates with a downwardly curved short extension of rail II2 at the transfer track means 4I to provide a bridge when the switch is closed for wheel 22 of the unconnected rail-riding means I5. y

In operation of the modification shown in Figs. 4 to 8 inclusive, assuming drive in a direction to cause the pulley wheels 2S, 25 to rotate clockwise,

wheels

22, 22 of a connected rail-riding means i6, supporting the leading end of a particular platform I4, will ride beneath operating arms 5I, 5I of switch plates E43, E43, as indicated in dotted lines at 52 in Fig. 7, causing the latter to be swung upwardly away from the ends of rails I I3, H3 to permit free passage of the transverse axle 23. After the rail-riding means I3 has passed, switch plates I43, i433 the latter will drop back to the positions indicated in Fig. '7, such as by force of gravity, to be interposed in the paths of

wheels

22, 22 of the trailing unconnected rail-riding means I5. lThus, as the connected rail-riding means I3 is being pulled up along upwardly curved extensions 3s?, 39, the unconnected rail-riding means I5 will be caused to ride up along switch plates |43, I 43 by lifting levers 3l', 3l and then transferred over to the downwardly curved extensions |42, I42, nally to be guided to the pair of inside upper rails I I2, I I2.

In reverse motion along the upper track I0 the unconnected rail-riding means I5 will thus lead the connected rail-riding means I 6 of a par-g ticular platform I4 and, with switch plates |44, |411 closed, the wheels thereof will continue on across the

sections

53, 53 of the pair of inside upper rails H2, H2 to the outer transfer track means at |38. At the latter, the unconnected rail-riding means I5 will be lowered by the leading levers 3l, 3i arranged in front of the transverse axle IZI at relatively the same speed as the connected rail-riding means I6 is lowered by the endless cables 25, at the inner transfer track means fil, rst down along the downwardly

curved extensions

42, 42 of the pair of outside upper rails I2, I2, and then down along the upwardly curved extensions 43, 48 of the pair of outside lower railsV I3, I5. The connected rail-riding means I8 is permitted to travel down the transfer track means at 4I by virtue of fact that the wheels 22, `22 thereof move forward beneath the operating arms 55, of the switch plates IM, IM, thus lifting the latter, as shown in Fig. 7. After that connected rail-riding means It has passed down to its inner transfer track means at 4I, switch plates IM, IM are permitted to return to their initial p-ositions, such as by force of gravity, so as to close the gaps in the pair of inside upper rails I I2, II2.

Followingr this action, the connected rail-riding means I6 of `a particular platform I4 will now have its

wheels

22, 22 located on the pair of outside lower rails I3, I3 and leading the unconnected rail-riding means I5, having its wheels arranged on the pair of inside lower rails H3, IIS, so that the action may be repeated with continued operation of the apparatus, which is the same for each of the successively arranged platforms therein. It will thus be seen that in this form of the apparatus of the present invention the switches are operated by the connected rail-riding means of each platform to permit free passage therebeyond of that rail-riding means, and that force of gravity closes the switches for the unconnected rail-riding means of the same platform. Of course, it will be understood that other suitable structure mounted on the platform may be employed to operate those switches.

The apparatus of Figs. 4 to 8 inclusive, may be operated in the reverse direction, since in such case, each connected rail-riding means I5 can be caused to open the switches for free passage by pushing against the rear sides of the switches, which after such passage will fall by force of gravity to the closed positions to handle the unconnected rail-riding means I5.

It will be noted that the employment of a plurality of dual rail structures, as proposed in the apparatus of Figs. 4 to 8 inclusive, will somewhat simplify the switch mechanisms while assuring the same desired functioning and it is to be understood that insofar as the novel trnasfer track means for positive guidance and suppport of the platform-supporting trucks at both ends thereof is concerned, switches may be eliminated by providing suitable short gaps in lateral and transfer vtrack means at certain of their junctures to permit free and selective passage of track-riding means in the present locations of the switches where needed.

It will thus be seen that the apparatus of the present invention provides positive guidance and sure support for the platform supporting means substantially at all times and in all positions, so that the apparatus is suitably adapted to the handling of weighted objects, such as automobiles. Thus the apparatus in any of the disclosed forms, or a variance thereof that `may readily occur to those skilled in the art, is efficiently adapted to compact parking of cars with effective conservation of space. In fact, two of such apparatus may be stacked one above the other with an approach and discharge ramp for one located above the other to provide four tiers of lateral banks at parking platforms.

From the foregoing, it will be understood that the apparatus of the present invention efficiently attains the objects set forth above, in addition to those made apparent from the preceding description, and, since certain changes may be made in the above construction and different embodiments of the invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interprete-d as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A conveyor apparatus for heavy loads comprising, in combination, upper and lower lateral track means each comprising two pairs of transversely spaced rails with those of one pair located inside those of the other and with the inside pairs being shorter than the outside pairs at one end of the apparatus and longer at the other end, two

sets of rail-riding means with those of one set adapted to ride on said pairs of inside .rails and those of the other setadapted to ride on said pairs of outside rails, a plurality of successively arranged platforms to be supported by and transported in one direction along one of said track means and then back along the other with each platform supported at one end thereof by railriding means of one set and at the other end thereof by rail-riding means of the other set, longitudinally spaced apart inner and outer transfer track means at each end of the apparatus each comprising a pair of rail structures with one associated with said pairs of inside rails and the other associated with said pairs of cutside rails and extending substantially continuously along paths between said upper and lower track means whereby the inner transfer track means at one end of the apparatus is adapted to guide by substantially continuous contact the rail-riding means of one of said sets from the inside pair of rails of one of the lower and upper lateral track means to the same pair of the other lateral track means, and the inner transfer track means at the other end of the apparatus is adapted to perform a similar function for the rail-riding means of the other set with respect to said pairs of outside rails, driven flexible endless means connected at spaced points to each of the rail-riding means of one of said sets with those of the other set un connected thereto, means guiding said endless means along said upper and lower track means and the inner transfer track means at one end of the apparatus and the outer transfer track means at the other end, other driven means to support and move the rail-riding means of said unconnected set along the remaining transfer track means at both ends of the apparatus substantially at the same rate of speed of the con* nected set of rail-riding means along their trans- IlY fer track means, switch means at ends of said inner transfer track means with one located at one end of the apparatus adjacent the upper track means and the other located at the other end adjacent the lower track means adapted a1- ternately to guide and support rail-riding means of one set and to permit passage of rail-riding means of the other set, switch operators for said switch means, and a plurality of operating means each associated with and connected to one of said platforms to move therewith automatically successively to operate said switch operators during platform motion.

2. The conveyor apparatus for heavy loads as dened in claim 1 characterized by the provision of said switch means in the form of rail sections which when in closed positions substantially ll gaps Vin one of the two tracks provided by said inside and outside rails and their associated transfer track rail structures for substantially continuous guidance and support of said railriding means along their respective tracks.

3. The conveyor apparatus for heavy loads as defined in claim 2 characterized by the provision of one of said switch means as apair of transversely spaced rail sections in the upper lateral track means beyond the junction with the in ner transfer track rail .structures at one end and the other of said switch means as another pair of transversely spaced railsections in the other inner transfer track rail structures at the other end in the vicinity of the junction thereof with said lower lateral track means.

4. The conveyor apparatus for heavy loads as dened in claim 3 characterized by the provision of means rigidly tying together the two switch rail sections in each of said pairs simultaneously to open similar gaps in the upper track means and simultaneously to divert similar sections of transfer track means from the lower track means.

5. The conveyor apparatus for heavy loads as dened in claim 4 characterized by the provision of each of said two switch means in the form of Va pivotally mountedV structure adapted to be swung upwardly to an open position by any one of said switch operating means and when freed from the latter to be permitted to fall to closed position.

6. The conveyor apparatus for heavy loads as dened in claim 5 characterized by the .provision Y FURMAN S. ABBOTT.

REFERENCES CITED The following references are of record in the le of this patent:

y UNITED STATES PATENTS Number f Name DateA 2,339,494 Lubahn Jan. 18, 1944 .Nalbach Dec. 4, 1945