US2694938A - Speed changer - Google Patents

Description

Nov. 23, 1954 Filed July 7, 1953 X. B. K. GREEN ETAL SPEED CHANGER 2 Sheets-Sheet l ///wz=r R6545, J12.

fire-mes Nov. 23, 1954 x. B. K. GiQEEN ET AL SPEED CHANGER 2 Sheets-Sheet 2 Filed July 7, 1953 X4 5 K G/FEEM Hale/9y P4 5815, .72. Ji l 671 7 195 United States Patent fifice 2,694,933 Patented Nov. 23, 1954 SPEED CHANGER Xan B. K. Green, New Paltz, and Harry Preble, Jr;, Cross River, N. Y., assignors to General Slicing Machine Co., Inc., Walden, N. Y., a corporation of New York Application July 7, 1953, Serial No. 366,479 8 Claims. (Cl. 74-356) The present invention relates to an apparatus to drive a shaft at different speeds, one speed at a time. These devices are usually called speed changers.

The principal object of this invention is to provide a novel and improved apparatus for driving a main shaft at any speed selected from a predetermined plurality of different speeds, and though such different speeds are respectively determined by other shafts in the system, none of all shafts mentioned are ever moved from their position to effect a change of speed of the main shaft, but a means is provided for selectively associating the main shaft with any of the others one at a time.

A further object hereof is to provide a novel and improved speed changer of the character set forth, wherein the selector means is permanently mounted, but is swingable to designated positions whereat by simple manipulation, it is locked in place and the required driving association established.

Another object of this invention is to provide a novel and improved speed changer of the class described, which is easy to use, simple in construction, reasonable in cost and efiicient in carrying out the purposes for which it is designed.

Other objects and advantages will become apparent as this disclosure proceeds.

In the accompanying drawings forming part of this specification, similar characters of reference indicate corresponding parts in all the views.

Fig. 1 is a side view of a speed changer embodying the teachings of this invention. Essentially it comprises a gear box whose casing is here shown in section so as to expose the gear and shaft system therein and a selector means swivelled on said casing.

Fig. 2 shows a longitudinal section of said selector means.

Fig. 3 is a front view of said selector means.

Fig. 4 is a front view of said gear box.

Fig. 5 is a diagrammatic front view of the gear systern of said gear box.

In the drawings, the numeral designates a frame which is rotatably mounted on the frame 16 about the axis line of the main shaft 17 which is to be given different speeds. Said shaft is journalled on frame 15 and securely carries a gear 18. A selector shaft 19 is rotatably and slidably mounted on the frame 15 and securely carries the gear 20 which is in constant engagement with gear 18. Frame 16 has journalled thereon as many shafts as the number of different speeds the main shaft 17 is to have. In the embodiment illustrated, three such shafts are included, namely 21, 22 and 23. All shafts mentioned are parallel and the axis of the main shaft 17 is equi-distant from the respective axes of shafts 19, 21, 22 and 23. The shafts 21, 22 and 23 are driven at different speeds. Such may be accomplished by a driver shaft 24 journalled on frame 16 and carrying secured thereon the three gears 25, 26 and 27 which are of different diameters, which respectively engage gear 28 secured on shaft 21, gear 29 secured on shaft 22 and gear 30 secured on shaft 23. Gear ratios are chosen so that the shafts 21, 22 and 23 have different speeds respectively. The driver shaft 24 is shown in alignment with the main shaft 17. For convenient design, each of the frames may be a casing as shown. In the machine art, the structure indicated generally by the numeral 31 may be called a gear box, while the numeral 32 designates generally, the selector mechanism The casing 16 may have a bearing plate 33 facing the selector mechanism 32. This plate is provided with holes therethrough as 34, for the respective shafts 21, 22, 23, to extend therein partway and serve as bearings for said shafts. It is the function of the selector shaft 19, to be engaged with any of said shafts 21, 22, 23, one at a time, whereby the main shaft 17 is driven at different speeds respectively. The swivel connection between the frames, is here afforded by providing. a sort of stud shaft 35 extending from the casing 15 into the central bearing hole through plate 33; there being an annular channel 36 on the periphery of said stud shaft which is engaged by the set-screw 37 threadedly engaged in the said plate 33 which plate is in the nature of a boss on the casing 16. The casings 15 and 16 are thus held in assembly and the swivel movement of the casing 15 may be halted and the casings secured in any set position of the selector mechanism 32, by tightening the set-screw 37. Loosening said screw somewhat, permits the mechanism 32 to be swung so that the selector shaft 19 is in alignment with any of the shafts 21, 22, 23. As will be explained, said selector shaft is movable into any of the shaft bearing holes as 34, and is retractable therefrom to permit movement of the selector mechanism 32 about its axis of swing on the casing 16.

The selector shaft 19, when in any of the bearing holes as 34, must be made to turn by the shaft which it meets. For this purpose, any suitable cooperating means is provided on each shaft end to be coupled, which provides a sort of clutch action. It is found practical to accomplish this by having the shaft end portions, of semi-circular cross section as shown at 33 on the selector shaft, and as at 39 on each of the shafts 21, 22 and 23. A suitable means for shifting the selector shaft 19 longitudinally, so that it shall enter or leave the bearing hole of any of the shafts 21, 22, 23, and stay in any position put, may be provided by the bearing structure denoted generally as 40, which moves along with and supports said shaft 19, when the latter is shifted longitudinally; the means for holding said bearing structure on the said shaft 19, being the retainer rings 41 secured on said shaft. Said bearing structure has secured thereon the rack 42 which is in engagement with a pinion 42 journalled on the body of the casing 15 and provided with the hand knob 43 for turning same. Said rack is of course parallel to the shaft 19 and may be provided with a locating pin 44 extending longitudinally therefrom in the direction of the gear box 31. It is evident that upon movement of the selector shaft 19 into one of the bearing holes 34, the pin 44 will set within a locating socket 45 in the plate 33 near such hole. The selector shaft fits slidably and rotatably in each of said bearing holes. The numerals 46 and 47 are bearings supporting and journalling the main shaft 17. The numeral 48 indicates a bearing supporting the selector shaft 19, for rotary and longitudinal sliding movements. The rack 42' and its pin 44 slide within the channel 49 in the body of the casing 15. The bearing 40 is the equivalent of a sleeve journalled on the selector shaft 19.

With the apparatus arranged as in Fig. 1, the shaft 24 may be driven by an electric motor or other motive power, and shaft 17 may be used to drive any machine, or carry a chuck. Knob 43 is then turned counter-clockwise to bring shaft 19 and pin 44 into casing 15. The screw 37 is loosened, whereby casing 15 may be swung to position the selector shaft 19 in alignment with any of the shafts 21, 22, 23. Upon one of the latter being selected for engagement, the knob 43 is turned clockwise whereby shaft end 38 will become engaged with the cooperative end 39 of the chosen shaft, and pin 44 will enter the related socket 45. Screw 37 is tightened to avoid undue vibration. It is evident that upon rotation of the selector shaft 19, the main shaft will turn because of the engaged gears 18 and 19. The speed of the main shaft 17 will of course depend upon which shaft the selector shaft 19 is in engagement with.

The apparatus herein taught may be used in permanent installations of machinery, or may be part of power-driven hand tools as for instance electric drills, saws, chuck-held tools, hair dryers, food mixers and other devices where speed change is desirable or mandatory.

This invention is capable of numerous forms and various applications without departing from the essential features herein disclosed. It is therefore intended and desired that" the embodiment herein shall be deemed illustractive and not restrictive and that the patent shall cover all patentable novelty herein set forth; reference being had to the following claims rather than to the specific description herein to indicate the scope of this invention.

We claim:

1. In an apparatus for selectively driving a main shaft at any one of a plurality of different speeds, a first frame, a plurality of shafts journalled on the first frame, means for driving said plurality of shafts at different speeds respectively; an end of each of said plurality of shafts extending to one side of said first frame, a second frame pivotally mounted on the first frame, a main shaft journalled on said second frame in alignment with the pivotal axis of the second frame; said main shaft extending from said second frame to be accessible for use, a selector shaft, rotatably and also longitudinally slidably mounted on the second frame, means associating the main and selector shafts for causing the rotation of the main shaft upon rotation of the selector shaft; all the said shafts being parallel to said pivotal axis; the axes of each of said plurality of shafts and of the selector shaft, being equi-distant from the axis of the main shaft, whereby upon swinging the second frame on the first frame, the selector shaft is moved into alignment with said plurality of shafts, one at a time; an end of said selector shaft extending free towards said one side of the first frame; said end of the selector shaft and each of the mentioned ends of said plurality of shafts, being provided with cooperative disengageable engagement means which cause the selector shaft to rotate with one of said plurality of shafts when engaged therewith respectively, means to hold the second frame against pivotal movement on the first frame when the selector shaft is in engagement with one of the plue rality of shafts and means to hold the selector shaft in engagement with the plurality of shafts respectively after said selector shaft is slid to establish such engagement.

2. The apparatus as defined in claim 1, including means on the second frame for moving and holding the selector shaft in and out of engagement with one of said plurality of shafts respectively when the second frame is swung so that said selector shaft is in alignment with said plurality of shafts respectively.

3. The apparatus as defined in claim 1, wherein the first frame has bearings which support the mentioned ends of the plurality of shafts respectively; each of said ends of said plurality of shafts extending only part way into said bearing respectively; the selector shaft being adapted to enter said bearings one at a time to be supported thereby prior to engagement with the shaft of said plurality of shafts in the bearing the selector shaft is entered into.

4. The apparatus as defined in claim 1, including a pin positioned parallel with the shafts, longitudinally slidably mounted on the second frame; the first frame, adjacent each of the mentioned ends of said plurality of shafts, be ing provided with a socket positioned to receive said pin respectively and including means on the second frame for moving and holding said pin and selector shaft into and out of engagement with said sockets and plurality of shafts respectively, simultaneously.

5. The apparatus as defined in claim 1, including a sleeve journalled on the selector shaft, a rack carried on said sleeve; said rack being positioned parallel with the selector shaft and longitudinally slidably mounted on the second frame, whereby said sleeve is maintained against rotation about the selector shaft, a gear journalled on the second frame, engaging said rack and handle means on said gear for manually turning same, whereupon the selector shaft is slid longitudinally.

6. The apparatus as defined in claim 5, including a pin extending longitudinally from the rack, the first frame, adjacent each of the mentioned ends of said plurality of shafts, being provided with a socket positioned to receive said pin respectively when the selector shaft is in position to engage the plurality of shafts respectively.

7. The apparatus as defined in claim 1, wherein each of the plurality of shafts carries a gear respectively and wherein the first frame comprises a casing housing said gears and including a driver shaft rotatably mounted within said casing and extending therefrom, and including a plurality of gears securely carried on said driver shaft within said casing; the gears on said driver shaft being engaged respectively with the gears on said plurality of shafts and wherein the second frame comprises a second casing and gears in engagement, respectively secured on the main and selector shafts within the second casing.

8. The apparatus as defined in claim 7, wherein the main and the driver shafts are in alignment and extend in opposite directions out of their respective casings.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 638,359 Schellenbach Dec. 5, 1899 667,406 Schellenbach Feb. 5, 1901 704,645 Isler July 15, 1902 749,186 Hagman Jan. 12, 1904 795,479 Butfum July 25, 1905 1,815,034 Boughton July 21, 1931 2,094,669 Pratt Oct, 5, 1937 2,642,756 Cummings June 23, 1953 FOREIGN PATENTS Number Country Date 977,638 France Nov. 15, 1950

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