US 1552068 A
Description (OCR text may contain errors)
Patented Sept. l, 1925.
UNITED SATATES'Y'PY A'r-ENT OFF-ICE- RALPH L. LEE, or DAYTON, OHIO, AssIGNOR To nELco-LIGHT COMPANY, OP DAYTON,
OHIO, A CORPORATION or DELAWARE.
Application filed August 3, 1923. Serial' No. 655,470.
Among the objects of the present invention is to operate the. reciprocating member 'or piston of a pump in a simple and effective manner. Y
Inv order to attain this aim Vof the invention, the embodiment shown herein provides a reversible velectric motor connected by means of suitable gearing with ainut vcooperating with a screw threaded shaft connected with the pump piston. Endwise movement of the nut is restrained so that revolution of the nut in opposite directions will effect axial movement of the screw threaded shaft in opposite directions. The screw threaded shaft is prevented from rotating by means of a spline and key connection with a stationary part. Means are providedl for reversing the electric motor, said means being controlled by the movement ofthe screw threaded shaft.
Other and further objects of the present invention will be appa-rent from the following description, reference being had to the accompanying drawings wherein a preferred embodiment of one form of the present invention is clearly shown.
The figure of the drawings discloses diaof the worm gear 35 is internally threadedV and functions as a nut cooperating with a lscrew threaded shaft 42. An unthreaded orammatically pumping apparatus includ-` end 43 of the shaft 42 extends into the pump cylinder 23 and functioning as a piston rod is connected with piston 24. The opposite end of. shaft 42 is, provided with a reduced :unthreaded portion 44, forming a shoulder 4 5. A stop member 46 is securedito said portion 44 adjacentits outer end. Rotation Vof shaft `42 is prevented by key47 cooperating with a groove 48 in shaft 42.
A reversing switch 50 comprises a switch arm 5l, provided with contacts 52 and 53 and pivotedV at 54..l A coil spring vis attached to a lever 56, .pivoted at 57, by a pin 58 and to switch arm 51 by a pin 59. kStops 6() and 61, spaced equally distant from the pivotpoint 57 limitthe throw of lever 56. Contacts 52 and 53 cooperate with' contacts 62 and 63, respectively, which are connected with the motor elds 31 and 32, respectively, by wires l64 and` 65,V respectively. Fields 31 and 32 are wound so as toproduce opposite magnetic effects withrespect to the motor armature to cause it to rotate Vin opposite Vdirections as the fields are successively and alternately connected with a current source. The opposite ends of these fields 31 and 32 are connected with 'motor bruslr68 by wires 66 and 67, respectively. Motor brush 69 and switch arm' 51 are yconnected with a suitable source of electrical current through c wires 70 and 71, respectively.
' Mode of operation.
Assumingthat the circuit connections are in the position shown in the drawings, the
'30 will rotate the shaft 33, causing the worm .f
34 to drive theV worm gear 35 and the hub y'38, to move the screw shaft 42 endwise to the right, asviewed iin the drawings, thus moving the pistonr 24 in the same direction, drawing fluid into the pump 20 through inlet 21 and forcing it out through outlet 22, in the usual manner. As the shaft 42 moves to the right, the shoulder 45 will come in con-tact with the lever 56, shifting it on its ...pivot 57. As soon as the lever 56 passes its lili) dead center, the spring 55 will snap the v switch arm 51 over, through its pivotal'conquickly broken and contacts 62 and 52 to be quickly brought together, thus exciting the nection 54, causing contacts 63 and 53 to be`v field 3l .and causing the motorBO to, rotate in the opposite direction. The circuit connections` willthen include wire 7l, switch arm 51, contact 52, Contact 62, `wire 64, field 3l, wire 66, wire 67, brush 68, motor armature, brush 69, and wires 70 and 71 being connected with a current source.
When the directionof rotation ofthe motor is reversed, the shaft 33 will be ro- ,tated in the Areverse directiom thus causing worm 3,4 to rota-te the worm gear 35 in a 'reverse direction thereby moving the screw shaft 42 and piston 241endwise to theI left as viewed in the drawing. As the shaft 42 moves to the left, the vstop 46 will come in Icentact with the lever 56, shifting it `on its pivot 57., Assoon as; the lever passes its dead center, the-'spring 5,5 will snap the switcharmlover., through its pivotal connection 54,1 causing contacts 52 and 62 to be vquicklybroken-andcontacts.63,.and 53 to be quickly brought togetherto produce arepetition of lthevv cycle `of operations heretofore :described Y 'f Y y Onefadvantage of the present .invention is theapplication off theffull vpower of the .primemover substantially at the beginning of .eachstroke of. theifpiston and the continuance of that application vof full power Luntill substantially the :end of the stroke. 4This is an effect which cannot 1 Lbe produced by the=usualcrank operatedspiston.v Y Another advantage vis that the space requirements are; less thanrequired for crank mechanism especial-ly when'thestroke of the piston is .relativelygreat Y While the yform of mechanism'. herein shown andndescribed constitutes a preferred v'embodimentof one form vof invention, it is to be understood -tlliatfother forms might be adopted and various changes and alterations made in the shape, size, and proportion of Vthe'elementstherein'without. departing from ment of Said Screw Shaft, @gerend-035th@v the? spirit Aand scope of` the invention.
yWhat is claimed isfasffollows: 4Pumping apparatus comprising, in combination,.a pump including a piston and la-'piston rod provided witha' screw-threaded port-ion; ar nuti for-operating vsaidpistonrod an electric motor for driving the nut and vincluding separate motor reversing fields; a'switeh for-rendering' either of the fields operative; and, connections between lsaid switch and piston rod whereby said field may be successively and alternately rendered operative automatical `2. Pumping apparatus comprising, in
ly to reverse themotor.
combination, a pump including a reciproeating piston; an electric motor having separate motor rreversing fields and an armature shaft with a worm cut thereon; a worm gear cooperating with said worm and provided with an internally threaded hub; a lscrew shaft extending through said hub and vccf'operating therewith but held against rotary movement, one end of the screw shaft lconnecting with said piston; a switchl for rendering either of the fields operative; and
provisions carried by saidscrew shaft whereby said fields may be nately rendered oper reverse the motor.
3. isumpingapparatus g comprising, in combination, fa pump including afreciprocat- `ing piston and, a' piston rod provided with a screw threaded portion; a nut cooperating with the threaded portion for Areciprocating successively and alterative .automatically toY said piston rod; an electric. motor for drivcombination, a pump including a reciprocat- `ing piston.; anelectric-motor vhaving separate :meter reversing fields and anyarmature shaft witha worm cut thereon; a worm gear cooper-ating with said 'worm vand provided with an internally threaded hub; a screw shaft Y,extending .through saidhub and cooperating therewithfto effect endwise movescrew shaft connecting withf'said piston; a switch for rendering ,either of the fields operative; andwprovisions carried by,y said screw shaft whereby said fields may be successively and alternately rendered operative automatically toreverse 'the motor.
In testimony whereof I hereto afiiX my signature.