US1803502A - Pedal construction and mounting - Google Patents

Description

May 5, 1931. G. A. FORSBERG PEDAL CONSTRUCTION AND MOUNTING Filed Feb. 20, 1928 2 Sheets-Sheet l May 5, 1931. V G, A. FORQBERG JSS PEDAL CONSTRUCTION AND MOUNTING Filed Feb. 20, 1928 2 Sheets-Sheet 2 Patented May 5, 1931 UNITED erriirizs. PATENT OFFICE HGUSTAV A. FORSBERG, OF CHICAGO, ILLINOIS, ASSIGNOR TO GULBRANSEN COMPANY,

OF CHICAGO, ILLINOIS, ACORPORATION OF ILLINOIS PEDAL CONSTRUCTION AND MOUNTING Application filed February 20, 1928. Serial No. 255,590.

This invention relates to player pianos, and more particularly to the construction and mounting of the pedals for operating the exn haust bellows of the exhaust power unit.

In the application of Axel G. Gulbransen for player piano, filed August 3, 1927, Serial No. 210,224 is disclosed a novel arrangement and construction of the power exhaust unit and the pedals for operating the same where- 1'6 by the pedals may be disposed in the same manner as the pedals of a hand played piano of standard type, the tone pedal being at the center of thertoe rail and the operating ped- A als being' disposed at oppositesides of the tone i5 pedal. This arrangement has proved to be highly eliicient both from the aesthetic standpoint and from the standpoint of operationA though I have found that, from the standpoint i of operation, the construction of the operating '2o pedals and the method of mounting of the same can be improved upon. These pedals are operated by the feet being alternately den pressed and released, as is well understood in the art. Vith pedals of the type disclosed bransen, above identified, the heel of the operators shoe rests upon the floor and provides a fulcrum point for movement of the foot in playing of the instrument. In the natural up and down movement of the foot in alternately depressing and releasing the` pedals, it is desirable that the upward move ment be not sutliciently great to tend to place the yleg muscles under strain, thus quicklyV tiring the operator. I have found that the most suitable position of the foot with the toe pressure thereof bearing upon the foot receiving portion or element of the pedal and the heel upon the floor, is at an angle of approximately 40 degrees to the floor surface. Vith the pedals mounted in such manner as to give this angle, suilcient throwof the pedal to properly operate the exhaust bellows of the power unit is obtained, and tiring of the leg muscles due to unnatural strain is avoided. At the initiation of the depression of the pedal there is a natural forward thrust of the toe portion of the foot due to the swinging vmovement of the footv about the point of contact of theheel of the shoe with in the copending application of Axel G. Grul-` the floor surface. By mounting the pedal for limited longitudinal movement to accommodate this natural forward thrust of the foot the point of the foot at which the pressure is applied to the pedal is not shifted but remains constant in the operation of the pedals and this is also of material assistance in preventing tiring of the foot muscles due to shifting of the point of application of pressure to the pedals, such as inevitably occurs where provision is not made for the limited longitudinal movement of the pedal referred to. A further object of my invention is to provide a flat foot plate suitably connected to the pedal to accommodate the compound movement thereof, this plate providing at all times an appreciable area of contact with the foot for applying pressure to the outer end of the pedal. Further objects and advantages will appear from the detailed description.

In the drawings:

` Fig. 1 is a fragmentary sectional view through the lower portion of a player piano case illustrating the method of mounting and operation of my pedal construction;

Fig. 2 is a plan view of the operating pedals and associated parts taken in the plane of the upper'edge of the toe rail;

Fig. 3 is a fragmentary side view of one of the pedals partly broken away and in section;

Fig. 4 is an outer end view of one of the pedals;

Fig. 5 is a section taken substantially on line 5 5 of Fig. fl looking down on the outer end portion of one of the operating pedals.

My invention is intended particularly for use in connection with a power exhaust unit indicated in its entirety by 1 which is mounted in the lower portion of casing 2 of a player piano of known construction such as that disclosed in the application of Axel Gr. Gulbransen above indentilied. The case 2 includes a removable lower front board 3, a toe rail 4, and 'a base board 5 Closing the lower end of the case. The unit 1 includes an equalizing bellows 6 secured to a pair of ex` haust bellows 7 which communicate with the equalizer 6, these exhaust bellows being sup- 1 illustrated or described in detail here.

ported by brackets 8 secured thereto and to the base board 5. Each of the bellows 7 is provided with an arm 9 extending therefrom, between which and the operating pedal is confined a connecting rod 10. The exhaust bellows is normally held in collapsed condi tion by a tension spring 11 having its ends secured to brackets 12 which are secured. to, the upper and lower leaves of the bellows. The intake of the equalizer 6' is connected by a tube 13 to the channel board ofthe instrument and, if desired, to the roll motor,.this vconnection being made through a. suitable throat structure and governor and associated parts as is well understood in the art. The construction and operation of the power unit and' associated parts is disclosed fully in thev copendingl application of Axel G. Gulbransen previously referred to, and need notI- exhaust power unit may be employed tofoperate the roll motor as well as to exhaust channell board, as stated, though I prefer to employ this unit for exhausting the channel board: only, the means for winding and rewinding the music sheet being operated from any other suitable separate source of power. Such means is disclosed inthe copendin ap plication of Axel Gr. Gulbransen for p ayer piano, Serial No. 163,016, filed J anuary 24,.. 1927, and in the copending application ot Arthur H. Boettcher for player piano, Serial No. 163,898', filed January- 27, 1927,'.

The connecting rod 1() is-provided, in: each. endA thereof, with, a pin 14;. Vrlhe pin. at theupper end of the rod passes through a felt bushing 15 extending through .an opening 16 at" the'inner-end of arm 9. A felt disc: 17 is secured to the upper end of rod 11andi provides a `cushioning element between the same and the arm 9. A second felt bushing 15 is provided about the-pin 14 at the lower end of rod. 10 and extends throughv an opening 18 at the inner end: of an L-shapedex l. tension 1-91of an operating pedal 20.. A sec- 0ndv felt disc 17 is` interposed` between the upper face of member 19 and the lower-end ofrod 10. The .openings 16.l and 18 are'of sufficient extent 'to permit relative move'- .me-nt between` the rod 1'0 and arm` 9; .and

member 19Ito accommodate raising and low.'-

ering of thepedal4 20 in the operation of the exhaust bellows 7 ,and the bushings; 15,- and discs 17 prevent any undesirable looseness; or metallic rattle between the pedals and theV associated means for operating the bellows.

Each of the pedals 20'has an outerior portionrwhich includes .a shank V 21 to which 'I the L-shaped extension 19 is secured by'capscrewsf22. This shank extendszthroug-h an opening 23through the .toe rail, which open-- ing is elted and is provided atitszibottom with .an outwardly tapering felt'` pad. asv

illustrated, to :cushion movement ofthe ipedal.

The shank 21 is provided with an upwardly projecting guard element 25 adjacent the outer face of the toe rail, which guard element functions in a known manner to prevent contact of the players toe with the rail 4, Upon depression of the outer end of the pedal 2(2),l the' rod 10 is raised so as to extend the bellows 7, exhausting the equalizer 6. Upon release of the pressure on the outer end of the pedal the top leaf of the bellows 7 is returned to lowered position through the laction of the tension spring 11 thus depressing the inner end of the pedal and raising the outer end thereof into normal operating position.

Shank 21 of the pedal is provided at its outer end with two spaced rounded lugs 26` separated. by a slot forming a rectangular recess: 27. An element 28 straddlesthe outer end of this recess and extends outwardly fromy the outer end of shank 2'1, the upper face 29 of this .element being disposed at an. inclination to the-horizontal of approximately 4Q degrees. Aswill be noted more clearly from: Fig. 3', the recess 27 is arched in the direction of its length and extends beneath and partially about a pntle screw 30 which extends through the lugs 26 and through ears 31- formed' integrally with and depending rom a foot plate 32, these ears being' disposed closely adjacent the outer faces of the lugs 26. A wire spring 33 is mounted about pintle 30 between the lugs 26' and has its lower arm 33a seated in a groove 34 in the-upper face of shank 21 and. eritencilingv from the inner end of recess 27;. The othera-rm 331i of spring 33bears against the under face of plate 32 above and inside of pint'leSO. This spring serves to urge thefoot plate-32 outwardly about the pintle 30 soa-as to `normally hold the under face of this plate inI contact with the inclined' face 29off elements 28. The foot plate 32 is thus normally disposed at what I have found to be the-proper'angle for most efficient operationk ofthe pedal without tiring-ot` the leg muscles due to subjecting them to unnatural strain.

With the heel of the shoe resting upon the floor as a fulcrum point, when pressure is exerted on thefoot plate 32 by the toe portion of the foot, there is, at the initiationy of the pressure on the outer end of the pedal, a natural. forward thrust effect of the foot and, i'f this'movement is not accommodated, the foot'is subjected to'unnatural strains with the result that' the foot muscles are quickly tired. Duringf continued downward movement. of-"the outer end of the pedal, if the pedal, be held against longitudinal movement, .the outer end of the pedal, in effect, mov-estoward the heel of the foot due to the arcuate travel of this outer portion caused byrswinging ofthe pedal about its pivot. As aresult,v it is necessary that there be relative the lower ends of these links.

sliding movement between the foot and the foot receiving element for applying pressure to the pedal. This means that the point of application of pressure by the foot shifts from one position to another during operation of the pedal thus subjecting the foot muscles to shifting and unnatural strains and quickly tiring them. I avoid these 0bjections by mounting the operating pedals in such manner as to accommodate the initial forward thrust of the foot and permit limited longitudinal movement of the pedal whereby the point of apl iication of pressure of the foot remains constant.

Referring more particularly to Figs. l and 2, each of the pedals 20 is supported from a substantially L-shaped bracket 34 secured by leg screws 35, or in any other suitable manner, to the base board 5. Outer supporting links 36 are pivoted at their lower ends, at 37, to the lower horizontal arm of brackets 34, the base board 5 being provided with a recess 38 in its upper face accommodating Links 36 are pivoted at their upper ends, at 39, to shanks 21 of pedals 2O the pivot 39 being disposed between the cap screws 22. The extension l9 of the pedal is provided at its inner end with a. depending vertical arm 40 formed integral therewith. The lower end of this arm is connected by a pair of links 4l to the upper end of the vertical arm 34a of bracket 34, the lower ends of links 41 being pivoted at 42 to arm 40 and the upper ends of these links being pivoted at 43 to arm 34a. In the operation of the pedal, with the foot F in operating position with the toe portion thereof resting upon the plate 32 and the heel resting upon the supporting surface or floor at a, the foot is disposed at an angle of approximately 40 degrees to the floor, this angle being such as not to subject the foot or leg muscles to unnatural strain. lWhen the pedal is depressed by exerting pressure on the plate 32, the pintle 30 moves through the arc b-c. Duringthis movement of the outer end of the pedal, the shank 21 swings about pivot 39 swinging the links 4l about pivot 43 into substantially horizontal position, causf ing the pivot 42 to move through the are e-fl and causing a consequent slight rearward movement of the pivot 42 permitting rearward or inward movement of the pedal in a longitudinal direction. This causes shifting of the pivot 39 rearwardly a slight distance so that the pedal is capable of a compound movement, that is, it has a swinging movement about the pivot 39 and has a simultaneous longitudinal movement which is limited in extent by the links 4l and the associated parts, As a result of this movement of the pedal, the forward thrust of the foot in depressing the pedal is accommodated, no relative sliding movement between the y foot and the foot plate or pressure applying element is necessary, and the point of application of pressure by the foot remains constant eliminating tiring of the foot muscles such as results from shifting this point of application. This has the advantage that the foot may be so placed when starting to operate the pedal as to apply pressure on the foot plate to the best advantage and with least effort, and the necessity for shifting the foot relative to the pedal is eliminated.

In practice the pedals 20 are disposed at opposite sides of and equi-distant from a tone or sustaining pedal 44 which operates through the toe rail 4 and is secured at its inner end to a rod 45 which has connection with the damper rail, this rod being rockably mounted in blocks 46 secured to the base board 5. This pedal and its function in operating the damper rail is well known to those skilled in the art. The construction and operation of the tone pedal is similar in all respects to that of the tone pedal disclosed in the copending application of Axel G. Gulbransen for player piano, Serial No. 210,224, filed August 3, 1927, previously referred to. The foot plates 32 are fiat and preferably have their upper faces knurled to prevent slipping, these plates being of sufficient area to provide an appreciable surface of contact for the application of pressure by the foot while eliminating interference by the tone pedal 44 with the operation of the operating pedals 20. By constructing and forming the operating pedals in the manner illustrated and described, I provide a thoroughly practical and highly efficient player piano in which these pedals are arranged similarly to and closely simulate the pedals of the standard type of hand played piano.

What I claim is:

l. In a player piano, an exhaust power unit, a pair of operating pedals pivoted intermediate their ends, operating connections between said unit and the pedals, and foot plates hinged to and disposed above the outer ends of the pedals and having rocking motion with respect thereto in the operation of the pedals.

2. In a player piano, an exhaust power unit, a pair of operating pedals pivoted intermediate their ends, operating connections between said unit and the pedals, foot plates hinged to and disposed above the outer ends of the pedals, yielding means urging the plates in one direction, and means limiting movement of the plates in such direction.

3. In a player piano, an exhaust power unit, a pair of operating pedals inounted for rocking` and limited longitudinal movement, operating connections between said unit and the edals, and foot receiving elements hinged to tie outer ,ends of the pedals and having rocking motion with respect thereto in the operation of the pedals, said elements being free from said connections.

4. In a player piano, an eXhaust power unit, a pair of operating pedals mounted for rocking and limited longitudinal movement, operating connections between said unit and the pedals, foot receiving elements hinged. to the outer ends of the pedals, yielding means urging said elements outwardly of the pedals, and means limiting outward movement of the foot receiving elements.

5. Ina player piano, an exhaust power unit, a pair of operating pedals mounted for rockinfr and limited longitudinal movement, foot receiving elements hinged to the outer ends of the pedals and disposed above the same, yielding means urging said elements outwardly of the pedals, and means limiting outward movement of the foot receiving elements and normallv holding them at an inclination downwardly and outwardly of the pedals.

6. In a player piano, an exhaust power unit, a pair of pedals, substantially L-shaped supporting brackets, said pedals having downwardly extending arms at their inner ends, links connecting the lower ends of said arms to the upper ends of the vertical arms of the brackets, links connecting' the horizontal arms of the brackets to the pedals, and operating connections between the pedals and said power unit.

7. In a player piano, an exhaust power unit, a pair of pedals, substantially L-shaped supporting brackets, said pedals having downwardly extending arms at their inner ends, links connecting the lower ends of said arms to the upper ends of the vertical arms of the brackets, links connecting the horizontal arms of the brackets to the pedals, operating connections between the pedals and said power unit, and foot plates hinged to the outer ends of the pedals. Y Y

8. In a pedal construction, a shank, a foot plate lhinged to the outer end of the shank, yielding means urging the plate toward the outer end of the shank, and means limiting outward movement of the plate and cooperating with said yielding means to normally hold the plate at an inclination downwardly toward the outer end of said shank.

9. In a pedal construction, a shank, a flat foot plate hinged to the outer end of the shank, an element eXtendino` from the outer end of the shank outwardly beyond the hinge axis of the plate and having its upper face inclined downwardly away from said shank, and yielding means urging` the plate outwardly of the shank and normally holding said plate with its under Pface seating uponv the upperxface of said element.

In witness whereof I hereunto subscribe my name this 15th day of February, 1928.

GUSTAV A. FOR'SBERG.

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