US1849092A - Extension top for desks and the like - Google Patents

Description

March 15, 1932. b. E. HUNTER I EXTENSION TOP FOR DESKS AND THE LIKE I5 Sheets-Sheet Filed Feb 27, 1928 D. E. HUNTER EXTENSION TOP FOR DESKS AND THE LIKE 3 Sheets-Sheet 2 Filed Feb. 27. 1928 m NWN March 15, 1932. D. E, HUNTER 1,849,092

EXTENSION TOP FOR DESKS AND THE LIKE Filed Feb. 27, 1928 3 Sheets-Sheet 3 face of the permanent top but one which abuts edgewise 'thereagainst thus affording no break or interval between. Such an ex' tension therefore possesses distinct advan-- Patented Mar. 15 1932 V I nairsnfsrarss' PANY, or MusKneon, ICHIGAN, A CORPORATION OF MICHIGAN T EXTENSION TOP EOE DESKS AND 'THE' LIKE Application filed February 27, lees. serial No. 257,160. a

This invention. relates ,to improvements in extension tops for desks, and more particularly to a sliding top or shelf capable of beingconeealed beneath the permanent top when-not in use, and to be' withdrawn -be-- position, and when so extendeclnot only pre sents a working surface-flush with the surtages over the ordinary type of extension top common to desks, tables and the l1ke, which are below the permanent top, and therefore while affording additional working area are not so positioned'as to be'the equivalent of an extension flush with the. permanent top;

Ma-nifestly an extension top of the character hereinafterto be described is not limited in isdisclosed in the accompanying drawings,

in which 7 .Flgure 1 is a top plan view of the portion of a desk top below which the extension top is located, portions of the permanent and ex-v tension'tops beingbroken away to' show the" supporting caniage beneath, Figure 2 is-a view in vertical transverse section taken on line 2' 2 of Figure 1.

Figure 3 is a view inlongitudinal vertical section through the front edge portion of the desk taken on 'line 3-3'of Figure 2 showing the extension top in retractedposition'. Figure 4c is a view similar to Figure 3 showing the top-extended preparatory to eleva v v a rollers to. slide in ahorizontalplane inward;

tion.' 1 i Figure5 is'aviewsimilartoFigure 4 showing the top elevated lntothe final position.

Figure 6=-is a detail view of oneof. the link connectlons between the top section and Icar -g,

toprovide 1 Parser 0mm nnv rn n. HUNTER, or MusKEeoN, MICHIGAN, assidnonrro THE SHAW ALKER comriage of the extension top astaken on line 66 of Figure 1. v m H 1Figure 'Zis a top plan view of one edge portion of a desk with extension'top and guard rail in extended position.

Figure 8'is a view in side elevation of-the extension top guard rail in extended position'.

'Fi'gure' 9"is'a view in front elevation of the-extension top and guard railin retracted position; and

Figure 10 is a perspective view of the same] parts in partially extended position;

For the purposeof this disclosure, the upper portion of metal desk is shown, includmg the 'permanenttop and a. space immediately below "in which the extensjible top is housed. According to the usual practice, the extension top is arranged to be withdrawn forwardly and into extendediposition at one a or bothsides of the desk, the-left side being I illustrated herein, v

. Referring now to the construction e1nbodyingthe features of the invention, the upper section of the desk is provided with a relatively shallow housing over which extends the topwall 1, and surrounded on three sides by side walls 2, 2 and a rear Wall 3, the front being open to provide an entrance slot for theexte'nsion top and from which theforward'edgethereof projects. The'top Wallis preferably covered with a" layer ofilinole'uin 1a or other covering material which forms the top surface of the desk.

As is the practice in metal furniture con structiomthe frame members and walls'of the desk are formed from blanks of sheet metal, shaped and spot-welded into a rigid structure but these details of construction need not be'elaborated upon; Within-the top casingis housed the extensibletop, cona fiat skeleton framemember mounted on ly and outwardly. Theltop 'section 5 isafiat.

Zsisting of two mainlandrelativelyshiftable -members, to wit, acarriage or sliding frame 4, and the top section 5. 'Tl1ecarriage.41.1s.-

i plate mounted upon and moving with itsca 'riage, and capable of beingishifted vertically andqhorizontally relative ithe'reto by. 'means ioe aintil the latter clears the front edge of the desktop, and then the top is swung vertically and horizontally to final position. The elevating and depressing of the top section is accomplished manually by lever actuated mechanism which imparts a parallel movement to the top. 7

As shown in Figures 1 and 2, the carriage 4 consists of a pair of longitudinal frame members 6, 6, consisting of strips of sheet metal bent into substantially S-shape (thus These frame members extend just below the side edges of the top section 5, and are connected together by three parallel transverse frame members 7, two being located at the ends of the carriage and one just forwardly of the rearmost member. These cross members are strips of sheet metal bent into inverted U-shape (thus L their ends being mortised and spot-welded tothe longitudinal frame members 6, 6.

The transverse frame member 7 at the extreme rear of the carriage forms a housing for a pair of pintle rods 8, 8, held in place by bolts 8a, 8a, these rods projecting from opposite sides of the carriage and carrying rollers 9, 9, at their extremities. These rollers engage track members 10, 10, secured to the side walls 2, 2, of the desk and extending from the rear end of the extension top housing to a point just short of its forward end.

7 These tracks are channel shape with roller engaging flanges projecting inwardly, the rollers 9, 9, being slightly less in diameter than the vertical distance between the flanges, both of which are engaged, depending on the position of the carriage and the distribution of the load.

Extending across the forward end of the extension top housing and forming the lower edges of the entrance slot thereto isa ll-shaped frame member 11 forming a part of the desk. Adjacent the ends of this frame member and in alignment with the downwardly facing channel, section 6a, 6a, of the longitudinal frame members 6, 6, are mounted stationary rollers 12, 12, journalled, in suitable roller bearings 13, 13. These rollerssupport the forward portion of the carriage, engaging downwardly facing tracks formed by the channel sections 6a, 6a, of the longitudinal carriage frame members 6, 6.

The extension top section 5 consists of a flat wall 14L covered with a layer of linoleum 15 and otherwise resembling a "rectangular sectionof thepermanent desk top. The edges of the top wall 14: are preferably surrounded by downwardly extending flanges 14a.

As shown in Figures 1 and 3, the top section 5 is somewhatshorter than the carriage 4, its rear edge terminating just forwardly of the intermediate cross member 7 of the carriage some six or seven inches from the rear end thereof, although its forward edge proj ects perhaps two inches beyond the forward cross member 7 of the carriage.

The top section is mounted on the carriage by two separate-pairs of connecting and operating members, one adjacent its rear end and the other adjacent its front edge and the members of each pair being located at opposite sides of the extension top assemblyiand comprising parts as follows: The rear pair of connecting members consists of links 16, 16, pivotally connected at one end to the carriage and at the other end to the top section through the medium of inverted U-shaped channel members 17 extending lengthwise of the underside of the top section and positioned just inwardly from and above the longitudin al frame members 6, 6, of the carriage and pintle pins 18 passing horizontally and transversely through the depending webs of said channel members. These pintle pins are free to turn on their axis, being fixed to one end of each of the links 16. A similar pivot mounting is provided for opposite ends of the links, there being provided along the inner edge portions of the longitudinal carriage frame members, 7 7, angle strips 19 with upstandingflanges 19a spaced from the side of the channel portion 6a of said longitudinal frame members, and in holes therein another pair of pintle pins 20, 20, for the opposite ends of the links 16 are journalled.

The connecting members at the front of the top section also include the operating parts consisting of the following mechanism: Just rearwardly of the foremost cross member 7 of the carriage frame, is a transverse rod or crank shaft 21 journalled at its ends in the inner vertical walls of the channel portion 6a of the longitudinal frame members 6, 6, of the carriage frame (Figure 2). Fixed to the shaft 21 just inwardly from the journalled ends thereof, are cranks 22 positioned in vertical alignment with the channel members 17 on the under side of the top plate 14. At the ends of the crank arms are transverse pins 22a which are j ournalled in holes punched in the outer depending flanges of the channel member 17. Midway between the ends of the shaft 21, is fixed an operatinglever 23 for turning the shaft 21 and cranks 22 and thus elevating and lowering the extension top as will now be described; reference being later made to the meansemployed for locking the operating lever to hold. thetop in elevated top section'4 lies fiatwise uponthe carriage.

position and for releasing the same for lowering the top. V

As is readily apparent from the foregoing. description, the position of theextension'topwithdraw thetop from the desk, it is merely pulled outwardly from the "front edge, the carriage 4 and top 5;moving as a unit, partly supported by the rollers 9, 9, and partly by the stationary rollers 12, 12. When the top is extended to a position beyond the front edge of the desk top in which its rearedge clears the same by an inch or so, its further with drawal is prevented by two stops 6band 612 secured to the longitudinal .frame members 6, 6, of the carriage and project downwardly for contact with the forward frame member 11 of the desk (Figure 3). f.

In the extended position (Figure 3)-the and in a depressed position. that is, with its surfacebelow that of the desk and a'space between the rear edge of the top and the front edge of the desk. Moreover, theoperating lever 23 is in a position extending horizon tally from the shaft 21 and in a rearwarddirection. The top section is elevated by reaching under the top, grasping the handle 230: at the end of the-lever and pulling'downwardly and forwardly thereon. By this movement the shaft 21 is rotated in a clockwise direction through at the same time rotating the cranks 22, 22, in a counter-clockwise direction (Figure 4) from a horizontal forwardly extending position to a vertical position. This movement of the cranks carries the top section 5 upwardly and rearwardly with a parallel movement, the links 16, 16, being the equivalents of the cranks, res ond to the force imparted to the cranks and also swing into a vertical position. This upward and rearward swinging movement of the top section thus simultaneouly brings the surface of the top section into the plane of the desk top, and brings itsrearedge into M abutting engagement with the front edge of In this connection it is to bethe desk top. I observed that the parallel movement of the top section is due to equality of the throw of'the cranks 21 and links 16, this .throwin turn being-equal to the radius of the are through which the top is swung'to bring it.

into .and out of, its elevated position;

The elevation of the top being a manual operation, additional means for holdingthe top] elevated position is required, since In the retracted position of the exotherwise "it would I return; to its depressed position :on the carriage .when the leveris released. :xThis means consists of locking 9 members acting on the lever 23 to hold the shaft 21. against turning-"and comprises a we I link 24 ipivotally connected to the lever 23,

midway of it's ends through the medium of a.

pin'25 passing.- through the link a short dis-. tance inwardly .fromits endand'an ear 23b integral withthe lever. r

The link 24 extends'rearwardly from the lever 23 and is connected'for horizontalslid-1' ing movement at its opposite end with a channel member 26 mounted on the underside of the top wall. 14 of the top section 5 approximately at its center and extending in a for; ward and rearward direction.- In one of the depending flanges of thechannel member26 is a longitudinal slot 26a in which the adj acent end of the link 24 slides, ashort'pin 24a forming theconnecting member. The length of the slot is such as to accommodate the} trave-lof the pin 24a from end to end in the swinging movement of the operating lever 23 r from the downward depending position shown in F i ure 4 to theirearward horizontal position of igure At the forward end of the slot 26a is a downwardly'olfset locking I notch 2 6b into which the pin24a drops when carried forwardly by the downwardswinging movement of the lever. In this position the link 24 assumes the function of abrace pre venting the lever23 from. being moved in either; direction and hence holding'the top firmly in elevated position To release the link 23 from the locking notch 26b sothat the top can be lowered, the handle 2300f the ice lever is grasped as before and by pressing V downwardly on the forwardly extending end I of the link, its rear end is lifted sufiiciently' to release the pin 24a from :thelocking notch 266 thus permitting it to slide rearwardly in the slot 26a and the top to resume its depressed position on the carriage. Thusde-c pressed, the carriage isfree to be pushed, backwardly into its retracted position within the desk.

In order to permit adjustment of the locking membersto compensate for'any slight variation in the assembly of the parts, the chan;

nel' member 26 is not fixed directly to the 'un-.

derside of the top but indirectlythrough an gle plate 27 having one flange 27a spot welded tothe'wall 14, andthe otherdepending in I flatwise contact with unslotted flange of the channel? member 26; 1 Through these contacting flanges are inserted bolts 28, 28, the bolt' holes in one ofthesflangesfl (preferably those in the fixed .angleplate) being elongated so that the channel member 26 can be moved slightly forwardly or rearwardly and thus, shift-the position of the slot26b asrequired.

As anladded'featuretobe applied in con junction withan extension'top especially: in a desk having vertically'extending walls-at the back and one or both sides thereof, is a telescopic side rail adapted to form an extension of the fixed guard rail along the corresponding side ofthe desk.

A desk provided with guard rails and an extension or telescopic guard rail is shown in Figures 6 to 9. These guard rails 29 are merely vertical extensions of the side and rear walls projecting 2 or 3 inches above the top surface of the desk and are desirable in some forms of desks, as for instance .for bookkeeping orother special purposes to prevent papers from being dislodged and scattered. Otherwise the desk and the extension top are the same as already described. The extension rail 30 consists of a strip of sheet metal bent into L-section and slidably mounted in a hou ing located along the angle between the top of the desk and the side guard rail 29, and formed by mounting a housing plate 31 of a corresponding L-shap-ed section to the inner face of the guard rail, and housing plate having 'a marginal flange 31a along its top edge which is spot welded to the face of the guard vious; Similarly the-extension rail is a convenient addition to the extenslon top although not a necessary ne.. Structural details and rail with the main body of the plate slightly offset so as to form a space of the same general sectional contour of the extension guard rail in which the latter can slideendwise with its horizontal web 30a flush with the surface of the desk. At the forward end of the ext-ensionguard rail 30 is a downwardly projecting pin 32 extending below the topof the desk and at one side of the top section 5 of the extension top. Fixed to the side edge of the top section is a bracket 33 having a vertical bore 83a therethrough and into which the pin extends for free vertical sliding movement. Thus as the extension top is with drawn from the space beneath the desk top the extension rail is withdrawn from its housing above the desk top. During the forward movement of the extension top, the top section is below the level of the extension rail, but on being elevated, its side edge is brought up flush with the under side of the horizontal web 30a of said rail 30, the latter being curved downwardly at its edge to provide an edgewise overlapping contact. Due to the sliding engagement of the pin 32 in thebracket 33, the top section is free to be shifted vertically relative to the rail as it is elevated or depressed and yet the connection is maintained so that they slide together to and from re-- tracted positions in their respective housings;

The advantages of anextension top embodying the features herein disclosed have already.

been pointed out, but otherwise would be obmechanical parts may be obviously varied without departing from the spirit of the invention, and therefore I'do not wish to. be

limited in either of these respects.

I claim as my invention;

position of said top section.

1." An extensible top for desks and the like comprising a carriage slidably mounted in a space below the top of said desk for withdrawal to and from extended position, a top section mounted on said carriage and adapted to normally assume a position below and forwardly of the desk top in the extended position of said carriage, links connecting one end and cranks connecting the other end of said top section with said. carriage, and a lever operatively connected with said cranks to rotate the same through a predetermined angle whereby said top section is swung upwardly and rearwardly from its position on said carriage when the latter is extended, to bring said top section into the plane of the desktop with its rear edge abutting the adjacent parallel edge of said desk top.

2. An extensible top for desks comprising a carriage slidable into and out of a space below the top of said desk,-and having rollers adjacent its rear edge, tracks fixed to said desk along the sides of said space and engaged by. said rollers, suporting rollers mounted onthe desk below said carriage at the front ofsaid space and supporting said carriage, atop ,ection mounted on said carriage for relative displacement, links connecting the rear portion of said top section with said carriage, cranks connecting the front portion of said top section with said carriage, a shaft journalled on said carriage and connected with said cranks, a lever mounted on said shaft, and lockingnieans interposed between said lever and said top section.

- 3. An extensible top for desks comprising a carriage slidable into and out of a space below the top of said desk, andhaving' rollers adjacent its rear'edge, tracks lixed to said desk along the sides of said space and engaged by said rollers, rollers mounted acent the front of said space and supporting said carriage, a top section mounted on said carriage and normally resting'in depressed posi' tion thereon below the level of the top of said desk with its rear edge spaced forwardly of the adjacent edge. of said desk top when said carriage is extended, pairs of cranks and links journalled on said carriage and connected with the under side of saie topsectiOn at points spaced apart lengthwise thereof, a shaft connecting said cranks, a lever mounted on said shaft and opera ive to swing said cranks through a predetermined angle to effect the parallel motion cf said top section into the plane of said desk top and in abutting contactat adjacent edges, a link pivotally connected 'at one en d with said lever, a slotted member mounted on the underside of said top section'and having slidable engagement with the other end of said link ahd a notch at one end of said slot adapted to prevent said: link from sliding inthe elevated lfAn extensible top for desks comprising a carriage slidable into and out of a space below the top of said desk, a top section mounted on said carriage and normally resting in depressed vposition thereon below the levelof the top of said desk, with its rear edge spaced forwardly of the adjacent edge of said desk top when said carriage'is eX-' tended, pairs of cranks and links journalled on said carriage and connected with the under,

side of said top section at points spaced apart lengthwise thereof, a shaft connecting said cranks, a lever operatively connected with said cranks to swing the same through a predetermined angle to effect the parallel motion of said top section into the plane of said desk top and in abutting contact at adjacent edges, a link pivotally connected at one end with said lever, a guide member mounted on the underside of said top section and having a slot slidably engaged by the other end of said link and a notch at one end of said slot adapted to lock said link against sliding for locking said lever in the elevated position of.

said top section, and to be released therefrom vto permit said top section to be depressed.

, 5. An extensible top for desks comprising acarriage shdable into. and out of a space below the top of said desk, an extension top section mounted on said carriage for displacement relative thereto, links connecting said top section with said carriage, a crank member mounted on said carriage and con nected with said top section, an operating lever connected with said crank member and coacting locking members on said topsection and carriage and operative by said lever to lock said top section in extended and elevated position.

6. An evtension top for desks and the like,

comprising a carriage slidably mounted in a space beneath the top of the desk and extensible therefrom to a position outwardly beyond and below the level of said desk top, a top section mounted on said carriage for vertical displacement in its extended position into and from the plane of said desk, means for normally elevating said top section, and releasable means for supporting said top section in elevated position.

7. An extensible top for desks and the like, comprising a carriage mounted below the top of said desk for sliding movement to and from an extended position below and beyond one edge thereof, a top section supported uponsaid carriage, rocking members connecting said top section with said carnage including a hand actuated crank for shifting said top section vertically andhorizontally into the plane of the desk top and into abutting contact at their edges, andmeans for locking saidcrank intheelevated position of said top section.

Signed at Muskegon this 23 day of' Feb DAVID E. HUNTER.

ruary, 1928.

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