US1276810A - Reversing screw-and-nut gearing. - Google Patents

Description

F. H.RAGAN. BEVERSING SCREW AND NUT GEARING. APPLlcAnoN FILED ocT.`13. '1913. RENEwEn MAY 2351918.

Patented Aug. 27, 191.8;

E D l i; f' s Z ,E JV Y wontarien 1 eran-as r canton FREDERICK HATHA'WAY RAGAN, 0F SEATTLE, WNASHINGTON.

REVERSINS: SCREW-AND-NUT GEA-RNG.

i Specification of Letters Patent.

Patented Aug. 2?, i918.

Application filed October 13, 191.3,- Seria'o. 795,012. Renewed May 23, 1918. Serial No. 235,233..

.machinefused in the manufacture of lumber,

which means will be under the complete coutrol of the operator, the action employed in `the operation of my power device being identical with that employed in the operation of the vpresent hand device. `By the introduction of my invention physical force heretofore relied. upon to operate the saw shifter is displaced, `therefore increasing the capacity of the mill, and at the same time insuring perfect accuracy.

Having thus indicated the ends sought by me my invention consists in the construction and combination of parts to be more ,fully described hereafter and particularly set forth in the claims'. Reference-.is to be had to the accompanying drawings forming part of this specification. in whichsimilar characters of reference indicate corresponding parts inall the figures.

Figure l 1s a perspective view of a standard edging machine with my invention embodied therein.

Fig. 2 is va longitudinal sectional view vof my power operating device;

Fig. 3 is a sectional view of Fig. 2 cut along the line 2 2, showing the operating vdevice engaging the handle lof the saw shifter of the edging machine.

As shown in thev drawings the rotary saw X Fig. l is moved along the shaft Z by force applied to the operating handle N, which isfraised to unmesh from -a ratch unvder the scale YS, vwhich holds the saw inthe position desired. v

It is to be observed that by pulling the lever N, in either direction,fguided by the iigured scale S, any width of lumber prede? c termined may be cut. y The feed'rollsR and fR revolving in the opposite direction feed- 255 the lumber against the saw X of which there are usually from nve to eight in number. l have shown but one in the drawings for convenience in description. rlhe rolls R and R are raised and lowered by air action in the 4cylinders C-and C to accommodate different thicknesses.

.My invention consists of two screw gears, B and B F ig.' l and Fig. 2 running the full length of the machine. To the front of each shifter I have bolted or otherwisefastened a small metal case A Fig. 1 through which the screw-gears pass. These screw gears are connected with an extension of the lower feed roll shaft by ordinary cog gears G, and sogeared together that the screws turn in the opposite direction. It is to be understood that power may be applied to these gears in any way desired, the one essential being that they turn in theopposite directions if thethreadings run in the same way.y

. I 'IlClOSed within the `meta-l case A Fig'.2.

are two round metal nuts M and M made of any suitable material. 'l In myvdrawingsthey are illustrated as having shoulders on each. side extending through the side of the case A to Aadmit of more thread '.,bearing "than would be possible in a plain nut.

These nuts and M ordinarily run free, aS they are snugly iitted to the screwsB and B and revolve with them and in .opposite 4 directions to each other. The ball `bearings .D and D as shown in Fig. 3 are designed to reduce friction with the'sides'- of the case A during this free motion. i

The case A is bolted or otherwise attached to the front ofthe shifter O as shown in Fig. 1. Extending through lthe upper face of said caseA is a forked yoke Y adapted to Y n permit the shifter handle N to rest therein. In place of the ordinary ridged handle such as is used in running the machine by hand I have substituted one which is pivoted at P .pressure is broughtfto bearupon the yoke Y. y If the pressure ,is exerted to the right of the yoke Y, a lifting movement is imparted to the communicating arms E and E, thereby bringing the wedges W and W which are attached thereto, into Contact with the nut M' which is running free with the screw B whiclris turning in the direction the lever has been previously tilted.

According to the amount of pressure eX-` erted by the operator, these vwedges will either fent-irely stop the free rotary motion of the nut which is turning with the screw or merely slow it up. Vhen the motion of the nut is retarded or stopped the screw will immediately begin tovwork through it, thereby carrying the case A along with it and likewise the shifter and saw to which the case is attached. The action is simply reversed by 'moving the handle N in the opposite direction, which releases the pressure exerted by the wedges upon the nut and thev nut resumes its free motion with the screw as before. The wedges have resumed their v mutual position between-the nuts M and `M until the tilt of the handle N in the opposite direction lowers the arms E and E and thereby retards or stops the nut on the screw B by the pressure communicated toit by the wedge as aforesaid described. y

The bottom sciew B is threaded the same way, but turning in the opposit-e direction from the screw B carrying the case A and shifter in the opposite direction.

The screws are run in suoli direction .that a pull to the right on the shifter handle N will move the case and the shifter to the right and vice versa.v When one nut is wedged and is pulling the shifter in the direction the thread of the screw is revolving, th'el other nut is pulling against the thread of the screw. thus picking up' an extra turn every three or four inches of the thread.

It will be observed that by placing a. spring on either side of the forked yoke Y Fig. 2 preferably'. on top of the case A the wedges 1V and if will be automatically centered between the nuts when the handle N is released. It is to be understopd that the wedges are made of any suitable inaterial preferably covered with a removable layer of friction material. The nuts likewise may be covered v'with a-layer of friction material.

The set screws H Fig. 3 Vas shown are accessible fromthc exterior of case A, and can be employed in adjusting the friction surfaces to correct any lossv of motion by reason of wear.

As can bc readily seen the satisfactory action of the apparatus, will depend largely upon the nuts immediately resuming their rotary motion after being freed from the wedges. In event hard usage and wear should render the nuts too loose to act upon 4I claim is new and the screw so that* adhesion between the screw and nut would not immediately overcome the friction between the side of the nut and the case A, small steel bars or a lug set into thenut from the peripheral surface and bearing upon the thread of the screw actuated by a spring an'd adjusted by a socket set screw will insure at all times the immediate rotary motion being resumed by the nut upon the releasing of the wedges.

The nuts may be turned with either a con- Y Athe shifter in position after being shut off.

from the friction wedges or other friction appliances. l

The friction element employed b'y my. in-

vention is one of the main features, since quarter inch and one-half inch sizes are marked on the scale and used continuously.

It is believed that no other method of op-.'

erating the saws by power can be made delicate enough to allow stopping whenever and wherever desired, and at the same time giving enough power when wanted to move the saws speedily over long distances.

The machine is simple and economical in construction, it is capable of increasing the capacity of'themill as it is awell known fact there has not been perfected a power operating device that has withstood -the crucial test of accuracy an element which cannot be sacrificed, hencethe continual use of physical power to operate the saw shifter in all up-to-date mills where modern inventions have supplanted the old methods in other departments.'

Having thus described my invention,.what j desire to protect by Letters Patent is;

'1. -A device of the class described coinprisiiig in combination, screw gears adapted to be continuously rotated, nutsfreely carried by said screw gears, oppositely located friction members disposed intermediate said nuts and adapted to bear. there against,- leverage means connecting said friction members, a casing disposed aroundsaid nuts and serving as a support for said leverage means, a handle adapted to engage said leverage means whereby pressure applied to said handle will be transmitted through said leverage means to one of said friction members thereby causing said member to frictionally engage one of said nuts and arrest its fiee rotative movement with said screw 'raffaele gear thereby longitudinally shifting said handle in the direction in vwhich pressure is applied.

2. A device of the class described ,corn-V prising in combination, a pair 'of screw gears adapted Ato be continuously rotated, cylindrical nuts carried by said. screw gearsand `adapted to revolve'freely therewith, oppositely located friction members disposed intermediate said cylindrical nuts, a easing disposed around said friction'members .and

"serving as a support for the same, a lever,Y links operatively connected to said friction members and having pivot connection with said-lever, said lever being' pivoted to said casing and having an upwardly projecting arm, a -lever vhaving a handle adapted to have contact with said arm, and meanswhereby said last named lever may retain said friction members in a neutral position outof contact. with said cylindrical nuts.

3. A device of the class described coniprising in combination, a pair of screw gears adapted to be continuously rotated, cylindrical nuts, freely carried thereby, said` screws passing through said nuts, i oppositely located vertical friction wedges having convergently inclined faces intermediate saidv nuts, a casing disposed around said .fricarm, a lever'having a handle adapted to be repos'ed in saidv U shaped arm, said casing being provided with a notch in the plane of said U shaped arm whereby the handle of said 'last named lever may retain said friction wedges in a neutral position out of contact with said cylindrical nuts.

Si ned by me at Seattle, Washington, this 4th ay of October, 1913.

FREDERICK Hiriiiwir RAGAN.

.Vitnesses RUTH P. RAGAN, ROY VAN MAREN.

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