US2792588A

US2792588A - Adjustable foot mechanism for sash balances

Info

Publication number: US2792588A
Application number: US520442A
Authority: US
Inventors: William E Gency
Original assignee: UNIQUE BALANCE CO Inc
Current assignee: UNIQUE BALANCE CO Inc
Priority date: 1955-07-07
Filing date: 1955-07-07
Publication date: 1957-05-21
Anticipated expiration: 1974-05-21

Description

NISM FOR SASH BALANCES May 21, 1957 w. E. GENCY ADJUSTABLE FOOT MECHA Filed July '1, 1955 INVENTOR. 5 WILLIAM E. GENCY' BY M, JAIL ZW hls ATTORNEYS United States Patent C William E. Gency, Old Greenwich, Conn., assignor to Unique. Balance Inc., New York, N. Y., a corporation of Illinois Application July 7, 1955, Serial No. 520,442 11 Claims. (Cl. 16-197) Thisinvcntion relates to mechanisms by means of which: the/tension of the springs 1 of spiralsash balances may be: adjustedand, more particularly, todevices of such character that may be incorporated in or adjacent to thefoot mechanism of 'the balancesin order to facilitatethe aforesaid adjustment. 1

Spiral'sash balances. of the general naturewith which this invention is concerned are illustrated, for example, in U. S. Patent No. 1,864,745. Various mechanisms haveheretofore been designed to permit of adjustment of the spring tension in these balances. ously suggested adjusting mechanisms,- however, have beeninadequateto' satisfythe requirements of the trade either because of the inherent difiiculty of manipulating them or because'the loca ion of the mechanisms has rendered them inaccessible after the balances have been installed. 7

An object of the present invention, accordingly, is to provide a mechanism by meansof which the spring tension of spiral sash balances of the above character may be readily adjusted after the balance has been installed.

Yet another object of the invention is to provide an adjusting mechanism of the above character which may beinexpensively manufactured and conveniently installed, the. mechanism being such as to permit themanufacture of a sub-assembly which may be installed on location and .connected'to the spiral balance mechanism, the spring tension of which is to be controlled;

Theforegoing and other objects are attained'by providing an adjusting mechanism that may, be incorporated in or carried by the structure of the footplate; the mechanism being so formed as to permit of adjustment by the application of a tool-such as a screw'driverthereto from apositiondirectly beneath'the foot plate. Furthermore, the mechanism utilizes aratchet and pawl connection normally biased into engaging position by a spring which is released by initial axial movement of the screw driver prior to the turning movement which effects the desired tension of the balance spring.

in order that theinvention maybe more readily understood, reference willnow be made to the accompanying drawings, wherein:

Fig. 1 is an exploded view of an adjusting mechanism constructed inaccordance with the present invention, this view illustrating the various partsin axial alignment;

Fig. 2 is a perspective view of. a conventional form of spiral sash balance and' its foot plate with the adjusting mechanism of the present invention incorporated therein;

Fig. 3 is.a view similar to Fig. 2;illustrating the manner in1which the :adjustment of the main spring of the. spiral sash balance may be efiected, the parts in this view being shown in a position in which they would exist at some point during the adjusting operation;

Fig. 4 is a view in horizontal section taken on the plane indicated by the line 4-4 and looking in the direction of the arrows; and

These previf Eatented May 21, 1957 ice Fig. Sisa view in vertical section taken .on the plane indicatedby the. line 55 and looking in the direction of the arrows.

Referring .tothe'above drawings, a conventional form of spiral sash balanceis illustratedgenerally at'10, the balance comprising a spiral.v spring 11, the upper'end ofwhich' is formed: with an;eye.12 which is adapted to be secured to the window frame and the lower end of which is formed. with a nut 13 having aslot 14 formed therein; Aspirally formed strip 15 is received within the. $101.14. and is formed witha. varying pitch, all in accordance with known practice.

In order that. the: spiral sash balance 10 maybe efie'ctively and conveniently secured to the window-sash, afootplatelS is provided in accordance with common practice. The-toot plate is formed with a tooth 17that iszdriven into the lower edge of the sash and with a suitable. number of: apertures l8 to permit the plate tobe secured to thebottomof the sash by means of screws,

In accordancewith this invention, the tension of the spring 11: or itsloading may be adjusted efiectively by armechanism comprising a-plate 19 that is formed-as an extension, somewhat offset, of the foot plate 16. A portion of": the .foot. plate is pressed upwardly into a stop or locatingdetent 20 to facilitate the location of'the foot plateiupon the bottom of the window sash and to prevent the. securing of the foot plate to the sash in such a positionasto impair the operation of the spring adjusting mechanism presently to be. described.

Upon opposite sides of the plate 19, pawl teeth 21- are formed in the. form of'the invention illustrated these teeth extending upwardly and lying generally in planes that are perpendicular to the plane of the plate 19. A central aperture 22 is formed in the plate 19 and is adaptedto receive oppositely spaced curved arms 23. The upper extremities of the arms 23' receive between them the lower end of the spiral member 15, a hinge pin 24 being provided-to secure these elements together. The upper extremities of the arms 23 are upset or flanged over to provide inwardly extending fianges 25, these flanges serving to make captive a coil spring 26 that is received between the arms 23.

As illustrated in Figs. 1, 2, 3 formed'upon an adjusting plate vided' with a slot'28 to receive the bit of a screw driver such as illustrated in phantom in Fig. 3 in order that the mechanism may be manipulated as will be presently describedi.

A ratchet plate 29 (illustrated particularly in Fig. 1) is formed-with oppositelydisposed notches or recesses 30 th'at are adapted to receive the pawls 21 and to prevent rotation'of the plate 29 in one direction (counterclockwise as viewed in Fig. 1). The plate 29 is formed with a diametrically extending bar 31 having a central enlargement 32 against which the spring 26 seats in order that the plate 29 may normally be urged downwardly and retained against theplate 19. As a result of the foregoing structure, spaced, semi-circular slots,33 are formed within the'plate 29 and through which the arms 23 extend whentheelements are in 'assemble'd'posi tion as illustrated in Figs. 2, 3, 4 and 5.

As illustrated in Fig: l, the parts; are assembled by inserting the" arms 23' through the central aperture 22 of the plate 19; placing "the plate 29in position over the plate 19 andwith the arms23 extendinggthrough the slots 33, then inserting the coil spring 26 between the arms 23 and peeningor hanging over the extehsionsZS into" the position illustrated-in Figs. 4 and 51 In this fashion, the coil spring 26 is captive and the elements including the foot plate 16 are formed as a sub-assembly. This sub-assembly may either be secured directly to the lower extremity of the spiral strip 15 at the time and 5, the arms 23 are 27, this plate being pro- 3- the sash balance is manufactured at the point of installation of the sash balance. All that is required is that the pin 24 be inserted through the apertures in the arms 23 and the aperture in the bottom of the spiral member 15 and then the straight end of the pin riveted over to secure the pin against accidental removal. In the assembled position, the lower end of the strip 15 is pressed against the coil spring 26 which in turn engages the central enlargement 32 to maintain the pawl teeth 21 in engagement with the ratchet plate 29.

Adjustment of the tension of the spring 11 'is'accomplished by inserting the bit of a screw driver (indicated in phantom at 34) into the slot 28. If the tension of the spring 11 is to be increased, then the screw driver need only be turned in a counter-clockwise direction as viewed from below in Fig. 3. This will cause the plate 29 to be moved in a corresponding direction and the pawl teeth 21 will move the plate upwardly to disengage the teeth from the notches 30 (turning of the plate 27 and 1. Au adjusting mechanism for spiral sash balances comprising a first plate carried by the foot-plate of a spiral means on said adjusting member to enable it to be turned by suitable instrument.

2. A device according to claim 1 wherein the means on ratchet and pawl to release balance. 7

3. A device according to claim 1 wherein the means for maintaining the ratchet and pawl relationship is a spring.

4. A device according to claim 3 wherein the ratchet mechanism comprises. a circular ratchet plate mounted between the first plate and the spring.

5. A device according to claim 3 wherein the extension is formed of twoarms and the spring is mounted between the arms. a

6. A device according to claim 5 wherein the arms are or be secured thereto comprising a first plate carried by formed with inwardly extending flanges overlying the spring to render the same captive.

7. A device according to claim 5 wherein the arms are curved to enclose said spring and the second plate is formed with a curved slot through which the arms extend.

8. An adjusting mechanism for spiral sash balances the foot plate of a spiral sash balance said first plate having a central aperture therein and two pawl teeth thereon, an adjusting plate rotatably mounted below thefirst plate, a ratchet plate above the first plate having two notches forming two ratchet teeth adapted to engage said pawl teeth and having two slots therein, a spring above said ratchet plate adapted to engage said ratchet plate tain said ratchet plate in engagement with said first plate, said adjusting plate having two arms thereon which extend through said central aperture and said slots, said arms having means whereby they may be secured to the lower end of a spiral sash balance, said adjusting plate having a slot therein to enable it to be turned.

9. An adjusting mechanism for spiral sash balances comprising a first plate carried by the foot plate of a spiral sash balance said first plate having a central aperture therein and two upstanding pawl teeth thereon, an adjusting plate rotatably mounted below the first plate, a circular ratchet plate above the first plate having two notches forming two ratchet teeth adapted to engage said pawl teeth and having two curved slots defining a diameter bar and a central enlarged portion of said bar, a helical spring above said ratchet plate adapted to engage said enlarged portion and thereby maintain said ratchet with said first plate, said adjusting a slot therein to enable it to be turned.

10. An adjusting mechanism for spiral sash balances comprising a first plate carried by the foot-plate of a thereby to disengage said ratchet and pawl and the tension of the spiral sash balance.

References Cited in the file of this patent UNITED STATES PATENTS 1,926,951 Larson Sept. 12, 1933 2,580,705 Tappen Jan. 1. 1952 2,622,267 Permi Dec. 23, 1952 and thereby main- 7