US 3487707 A
Description (OCR text may contain errors)
FORMING MILL DRIVE Filed June 13,1968 4 Sheets-Sheet 2 ATTORNEYS N m M TD R L O L Km A m I m F Fan. 6, 1970 4 Sheets-Sheet 4 Filed June 13, 1968 ATTORNS United States Patent 3,487,707 FORMING MILL DRIVE William A. Kortan, North Olmsted, Ohio, assignor to The Yoder Company, Cleveland, Ohio, a corporation of Ohio Filed June 13, 1968, Ser. No. 736,699 Int. Cl. F16h 35/00, 57/00 U.S. Cl. 74-384 19 Claims ABSTRACT OF THE DISCLOSURE This invention relates generally as indicated to a forming mill drive and more particularly to an improved mill drive for a roll forming head, the top shaft of which may easily be disconnected or its speed changed.
A conventional roll forming head or stand includes a top shaft which is driven from a bottom shaft by means of a spur gear train. The train includes two idler gears which are connected to the top shaft by a toggle linkage and this maintains the gears in mesh running on their designed pitch diameters regardless of the center distance of the shafts. In this manner, the top shaft is able to separate from the bottom shaft in a vertical direction by, for example, a distance from about 4 to about 8 inches.
Normal top to bottom gear ratios are either equal (1 to 1) or something on the order of 1.8 to 1. The ratio selected accommodates the most effective and economical roller die design. In a job shop type of roll forming operation, it is frequently required that there be many sets of rolls involved, and that the gearing must be changed from equal to unequal ratio or vice versa quite often. In order to do this in the above described conventional rolling mill head, it is necessary to remove the toggle links, idler and driven gears, and replace them with the opposite ratio set of gears and links. Occasions are frequently encountered where it is necessary to idle the top shaft because of the pitch diameters of the roller dies employed and in this case it is then necessary to remove a toggle link pin and withdraw the top idler spur gear and its related parts and then replace the link pin in the links. It can thus be seen that the shifting from equal to unequal gear ratios or the idling of the top shaft has required the disassembly and reassembly of the spur gear train and has thus entailed considerable machine down time.
It is accordingly a principal object of the present invention to provide a forming mill in which the gear ratios of the top to bottom shaft may easily be changed or in which the top shaft may be idled without requiring any significant mill down time.
Another principal object is the provision of a forming mill wherein it is possible to change the gear ratio of the top to bottom shaft, or completely idle the top shaft without removing or changing any components of the mill drive.
A further object is the provision of a mill drive of the type above described utilizing dual faced gearing with the such gear on the top shaft merely being shifted to change the gear ratio or completely idle the top shaft.
Still another object is the provision of a shaft to shaft forming mill drive wherein one shaft may be idled simply by rotating the position of an idle gear mounting.
A yet further object is the provision of a forming mill greatly facilitating the changing of roller die sets thus 3,487,707 Patented Jan. 6, 197@ making a roll forming mill more economical in a job shop operation.
Other objects and advantages of the present invention will become apparent as the following description proceeds.
To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principles of the invention may be employed.
In said annexed drawings:
FIG. 1 is a vertical section taken axially of the vertically spaced shafts of one form of roll .forming head or stand in accordance with the present invention;
FIG. 2 is a vertical fragmentary transaxial section taken substantially along the line 2-2 of FIG. 1;
FIG. 3 is an enlarged fragmentary section of the gear drive between the top and bottom shafts taken substantially on the line 3-3 of FIG. 2;
FIG. 4 is a vertical section of the top shaft dual face gear taken substantially on the line 4-4 of FIG. 3;
FIG. 5 is an enlarged fragmentary section similar to FIG. 2 showing another form of the present invention utilizing a special mounting for the top idler gear to facilitate the idling of the top shaft;
FIG. 6 is an enlarged fragmentary section of the embodiment of FIG. 5 taken substantially on the line 66 thereof; and
FIG. 7 is an enlarged end elevation of the mounting of the top idler gear as seen from the line 77 of FIG. 6.
Referring first to FIGS. 1 and 2, there is illustrated a roll forming head or roll stand for a forming mill which includes top and bottom shafts 10 and 11 on which are mounted roller dies 12 and 13, respectively, for the roll forming of work W. The work W is illustrated as a tubular product, but it will be appreciated that a wide variety of shapes may be formed by passing elongated strip material through a plurality of such roll forming heads progressively to form the strip into the desired product.
The roll shafts 10 and 11 are journalled at opposite ends in inboard and outboard stands 14 and 15, the former being a gear head housing. The lower roll shaft 11 is journalled at 16 in the outboard stand 15 and at 17 and 18 at opposite sides of the gear head housing or inboard stand 14. In addition to the journals indicated the lower roll shaft includes a shaft nut 19, spacers 20 and 21 for the roller dies 13, and spacers 22, 23 and 24 within the inboard gear head housing 14 which position and space spur gear 26 and worm gear 27 which are secured to such shaft 11. The worm gear 27 is in mesh with worm 28 mounted on line shaft segment 29, which as seen in FIG. 2 may be secured through coupling 30 to additional shaft segments and thus drive as many roll forming heads or stands as are used to form the roll forming mill. Power is supplied to each of the roll formin heads in the mill through the line shaft. The line shaft segment 29 is journalled as indicated at 31 and 32 in the gear head inboard housing 14.
The top roll shaft 10 is journalled at 34 and 35 in blocks 36 and 37 which are mounted in windows 38 and 39 of the outboard and inboard housings, respectively, for vertical movement. Such vertical movement is obtained by rotation of nuts 41 and 42 which are in mesh with the threaded portions of rods 43 and 44, respectively, pin secured to the blocks 36 and 37. Rotation of such nuts is facilitated by the use of crank handles 45 seen more clearly in FIG. 2 and lock nuts 46 and 47 may be employed to secure the position of the shaft 10 in its desired vertical adjustment.
In addition to the journals 34 and 35 shown, the top roll shaft includes shaft nut 49, spacers 50 and 51 for the roller die 12, and on the end projecting within the gear head or inboard housing 14, a sleeve 52 keyed to such shaft as indicated at 53. Beyond such sleeve there is provided a roller bearing 55 held in place by lock washer and nut 56 secured to the end of the shaft 10.
The bearing 55 journals on the end of the shaft 10 an offset toggle link 58 as seen in FIG. 3 which supports one end of pin 59. The opposite end of the pin 59 is supported by toggle link 60 pivotally secured to hub 61 surrounding the sleeve 52 adjacent the block 37. The pin 59 is also supported by toggle links 62 and 63, the latter being offset as indicated in FIG. 3, such links extending between the pin 59 and stub shaft 64 mounted in bosses 65 and 66 at the interior and exterior, respectively, of the inboard stand or gear housing 14.
A double faced idler gear 68 is journalled on the shaft 64 by means of roller bearing 69 between the toggle links 62 and 63 and the smaller face of such gear is in mesh with the spur or drive gear 26 on the bottom roll shaft 11. The larger face of the double faced gear 68 is in mesh with the smaller face of double faced gear 70 journalled on pin 59 by roller bearing 71. Such double faced gear is positioned between the links 62 and 63 with the former including a spacing hub 72. Power is thus transmitted from the bottom roll shaft 11 through the spur gear 26 to the bottom dual face idler gear 68 to the top dual face idler gear 70 and then to a top drive gear 74 having laterally spaced dual faces 75 and 76. The distance separating the two faces 75 and 76 of the top drive gear 74 is slightly greater than the Width of the dual face idler gear 70, the two faces of which are adjacent to each other. The top drive gear 74 is keyed to the top shaft, also by means of the key 53, but is free to slide on the sleeve 52. The top drive gear 74 is held in any one of three selected positions as determined by locking set screw 78 into one of three annular grooves 79, 80 and 81 in the sleeve 52.
With the top drive gear 74 slid to the left-hand position as seen in FIG. 3, and the set screw 78 in the left-hand annular groove 79 of the sleeve 52, the smaller gear face 76 is meshed with the larger gear face of the top idler gear 70, and followin through the gear train, the top and bottom shafts would be rotating at the same r.p.m. and hence would be equal geared.
By shifting the top gear 74 to the middle position so that the set screw 78 is located in the center groove 80 of the sleeve 52, neither of the two faces 75 and 76 are in mesh with the top idler gear 70 and accordingly the top shaft 10 is free to idle and run at its own speed. By shifting the top gear 74 to the extreme right-hand position as seen in FIG. 3 so that the set screw 78 is in the righthand groove 81 as indicated by the phantom line position 83, the large face 75 of the top drive gear 74 is in mesh with the smaller face of the top idler gear 70, and following through the gear train, the top and bottom shafts are then rotating at different r.p.m.s and are thus unequally geared.
The inboard or gear head housing 14 is provided with a cover 84 which can readily be removed to provide access to the set screw 78 so that the gear 74 may readily be shifted to any one of the three selected positions. It is also noted that a flexible boot 85 is provided between the shaft journals 35 and 17 for the top and bottom roll shafts, respectively, to protect the interior of the gear housing from contamination.
With this invention, the top shaft 10 is able to separate from the bottom shaft 11 in a vertical direction which may, for example, be a distance from about 4 to about 8 inches and the gears 26, 68, 70 and 74 are always held in mesh regardless of the center distance of the shafts by the pair of toggle links 58, 60 and 62, 63. This toggle linkage ensures that the gears always run on their design pitch diameters. It can thus be seen that with this embodiment of the invention, it is possible to change the gear ratio of the top to bottom shaft, or completely idle the top shaft without removing or changing any components. This 18 accomplished simply by shifting the top dual faced drive gear 74.
THE EMBODIMENT OF FIGS. 5, 6 AND 7 While most roll formed shapes can be run with one or two gear ratios, it is frequently encountered in job shop type roll forming operations, that rolls involving many different ratios are tooled for short production runs and that if the tooling ratio does not match the built in gear ratio, it is necessary to disconnect the top roll shaft and run only with the bottom shaft driven. This, of course, can be accomplished in the embodiment of this invention illustrated in FIGS. 1 through 4 by placing the top gear in its center or neutral position. In many cases, particularly in job shops, there may not be a need for both a two speed and idle drive. A more desirable drive might be one that gives but a single gear ratio and the ability to idle the top shaft whenever needed. This type of a much more simplified drive is shown in the embodiment of FIGS. 5 through 7.
Referring first to FIGS. 5 and 6, it Will be seen that the top roll shaft is positioned vertically above the driven bottom roll shaft 91 and as in the FIG. 1 embodiment, the top roll shaft may be moved vertically. The top roll shaft 90 is driven from the bottom roll shaft by a spur gear train which includes a gear 92 mounted on the bottom shaft in mesh with a bottom idler gear 93 journalled on stub shaft 94 by means of the roller bearing 95 seen in FIG. 6. A pair of outwardly offset toggle links 96 and 97 extend from the stub shaft 94 to toggle pin 98. A top idler gear 99 is journalled by means of roller bearing 100 on the circular center portion 101 of the toggle pin 98. Toggle links 102 and 103 extend from the center portion 101 of the pin 98 to the top roll shaft 90. A gear 105 is keyed to such shaft and is in mesh with the top idler gear 99.
The toggle pin 98 includes two circular end portions 108 and 109 concentric with each other journalling the pin for rotation in the toggle links 96 and 97. These end portions 108 and 109 are, however, eccentric with respect to the center portion 101 of the pin to which the links 102 and 103 are connected. The idler gear 99 as well as the links 102 and 103 are mounted concentrically of the center portion 101 of the pin. Therefore, any rotation of the pin will not disturb the pitch line center distance between the top idler gear 99 and the top drive gear 105. As seen in FIG. 7, the distance between the center A of the concentric circular portions 108 and 109 and the center B of the center eccentric circular portion 101 may, for example, be a distance of approximately & of an inch which is equivalent to slightly 'more than twice the addendum of the spur gear tooth form.
In order to disengage the gear train, it is only necessary to rotate the pin 98 through and this will have the effect of moving the gears 93 and 99 apart sufficiently to disengage them. To facilitate this rotation of the pin, the right-hand end of the pin as seen in FIG. 6 is squared as indicated at 111 and a keeper plate 112 adapted to engage the flats of the square is mounted on the link 97 through the dual slot and fastener connection 113 seen more clearly in FIG. 7. In this manner when the keeper plate is loosened and moved away from the pin it is possible to rotate the pin through 180 and then reset the keeper 112. The half turn rotation causes the two idler gears 93 and 99 to become separated and the top shaft 90 is then free to idle.
It can now be seen that there is provided an improved roll forming head which includes a toggle linkage gear train drivingly interconnecting the top and bottom shafts whereby the speed of the top shaft may conveniently be changed or the drive thereto disconnected.
I, therefore, particularly point out and distinctly claim as invention:
1. A roll forming head comprising vertically spaced roller die shafts, means vertically to adjust the position of the top shaft, and a toggle linkage gear train drivingly interconnecting said shafts including mean operative to disconnect said top shaft.
2. A roll forming head as set forth in claim 1 wherein said last mentioned means comprises an eccentric pin in said gear train on which one of the gears thereof is journalled.
3. A roll forming head as set forth in claim 2 including means to rotate and contra-rotate said pin 180. to engage and disengage adjacent gears in said train.
4. A roll forming head as set forth in claim 3 including opposite flats on one end of said pin, and a retractible keeper plate bearing against said flats to maintain said pin in its selected position.
5. A roll forming head as set forth in claim 2 wherein said gear train includes a pair of toggle links pivoted at one end to said top shaft, a drive gear on said top shaft therebetween, said eccentric pin extending between the other ends of said links and having journalled thereon an idler gear in mesh with said drive gear, said links and idler gear being mounted on a circular portion of said pin having one center, said pin being supported at another center thereof with respect to another gear in said train, whereby said idler gear and said other gear may be moved toward and away from each other by rotation of said pin.
6. A roll forming head as set forth in claim 5 including an offset shaft parallel to said bottom shaft on which said other gear is journalled, a drive gear on said bottom shaft in mesh with said other gear, and a second pair of toggle links extending from said offset shaft to said eccentric pin, said second pair of toggle links being pivoted to said pin at said other center thereof.
7. A roll forming head as set forth in claim 1 wherein said last mentioned means comprises a gear on said top shaft, and means to slide said gear therealong to disengage said gear from the adjacent gear in said train thus to disconnect said top shaft.
8. A roll forming head as set forth in claim 7 wherein said gear on said top shaft includes two axially spaced faces having different pitch diameters, the adjacent gear in said train also having two faces of different pitch diameter, each being adapted to mesh with one of the faces on the gear on the top shaft, and means to slide said gear on said top shaft along said top shaft to engage the faces thereof with the respective faces of said adjacent gear thus to change the speed of said top shaft.
9. A roll forming head as set forth in claim 8 including a sleeve on said top shaft on which said gear on said shaft is supported for sliding movement, and means interconnecting said gear and sleeve properly to position said gear with respect to said adjacent gear to change the speed of said top shaft or to disconnect said top shaft from said gear train.
10. A roll forming head as set forth in claim 9 wherein said sleeve includes axially spaced annular grooves, and a set screw in said gear on said top shaft operative to fit within a selected one of said grooves to hold said gear in the selected position on said sleeve.
11. A roll forming head as set forth in claim 7 wherein said adjacent gear is supported on a pair of toggle links extending from said top shaft, an offset shaft adjacent said bottom shaft, said adjacent gear also being supported by a pair of toggle links extending from said offset shaft.
12. A roll forming head as set forth in claim 11 including a drive gear on said bottom shaft, an idler gear journalled on said offset shaft and in mesh therewith, a pin supported by said toggle links between said offset shaft and said top shaft, said adjacent gear being journalled on said pin and in mesh with the idler gear on said offset shaft and the gear on said top shaft.
13. A roll forming head as set forth in claim 12 wherein said adjacent gear and the gear on said top shaft are dual faced gears whereby the speed of the top shaft may be changed by sliding the gear therealong.
14. A roll forming head as setforth in claim 1 wherein said last mentioned means comprises means operative axially to shift one of the gears in said train to disconnect said top shaft.
15. A roll forming head as set forth in claim 14 wherein the shiftable gear and the adjacent gear have dual faces whereby the speed of the top shaft may be changed upon shifting of said gear.
16. A roll forming head including top and bottom roller die shafts journalled between inboard and outboard stands, means to raise and lower said top shaft with respect to said bottom shaft, said top shaft being driven from said bottom shaft through a toggle linkage gear train in said inboard stand, and means operative axially to shift one of the gears of said train to change the speed of said top shaft with respect to said bottom shaft or to disconnect the same.
17. A roll forming head as set forth in claim 16 wherein said one of the gears is on said top shaft and includes two faces, the adjacent gear in said train also including two faces, the two faces of said one gear being separated by a distance slightly greater than the width of the dual faced adjacent idler gear.
18. A roll forming head as set forth in claim 17 including a sleeve on said top shaft supporting said one of said gears thereon, and means interconnecting said sleeve and one gear to position said one gear in three selected positions, the middle position disconnecting said top and bottom shafts.
19. A roll forming head as set forth in claim 18 wherein said means interconnecting said sleeve and one gear comprises annular slots in said sleeve and a set screw in said one gear.
References Cited UNITED STATES PATENTS