US2024860A

US2024860A - Self contained electric knife sharpener

Info

Publication number: US2024860A
Application number: US718760A
Authority: US
Inventors: Louis C Hobart; Kenneth F Lees
Original assignee: OLYMPIC IND CORP
Current assignee: OLYMPIC IND CORP; OLYMPIC INDUSTRIAL Corp
Priority date: 1934-04-03
Filing date: 1934-04-03
Publication date: 1935-12-17
Anticipated expiration: 1952-12-17

Description

Dec. 17, 1935. c. HOBART ET AL SELF CONTAINED ELECTRIC KNIFE SHARPENER Filed April 5, 1934 Q 4 A 4 .B [k ,V 5 a 9 4 7 a y y y g 8 4 5 S Rmzmv O E E TBL N No .WR E V .HCT mam T i M M wKw Patented Dec. 17, 1935 UNlTED STATES PATENT OFFICE,

SELF CONTAINED ELECTRIC KNIFE SHARPENER.

Louis C. Hobart, Southington, Conn, and Kenneth F. Lees, New York, N. Y., assignors to The Olympic Industrial Corporation,

New

This invention relates to electrically operated knife sharpeners. It is one of the principal objects of the invention to provide a device of this kind that is a complete, self-contained, unit furnishing from within itself the energy required for its operation. Another-object is to make possible in a mechanism of this kind, the use of standard small battery cells. A further object is to provide in a device of this kind novel means for imparting reciprocating motions to its sharpening members. A still further object is to make the device readily adaptable for economic manufacture. Still another object is to secure in a device of this kind by means of its particular construction maximum power with minimum current drain for a longer possible life of the battery cells. Further objects will become apparent in the following specificationand the accompanying drawing in which a preferred embodiment of the invention is shown.

In the drawing,

Fig. l is a longitudinal vertical sectional view of the sharpener;

Fig. 2 is a vertical sectional view along the plane of line 2-2 in Fig. 1;

Fig. 3 is a partially cut-away bottom view of the sharpener with its energizing mechanism and its bottom closure plate removed;

Fig. 4 is a plan view of the sharpening members proper shown in an engaging position;

Fig. 5 is a perspective view of one of the sharpening members; and

Fig. 6 is a wiring diagram indicating the electrical connections between the principal component parts of the sharpener.

Like characters of reference denote similar parts throughout the several figures and the following specification.

I0 is a housing, preferably made of bakelite or other suitable material, consisting of a substantially rectangular base portion II, and a top portion l2, superimposed upon the base portion II, also rectangular in shape. The base portion is open at its bottom and closed by a platev I3 suitably secured to the housing by means of screws. The top portion l2 has a substantially square opening 14 at its uppermost surface, extending somewhat down its sides in the shape of a V at I.

Attached to the inside of the housing H1, at the top of the base portion. II, and secured thereto by screws, is a support plate I 8, its ends fitted, preferably, into recesses I! at the inside of the housing. I8 is a rectangular coil cage riveted to the support plate I 8 and projecting into the top portion I2 of the housing II). This cage l8 which is preferably made of sheet metal has one end closed at I9. 20 is a central core fastened to the end l9 having a coil 2| wound around it, a washer 22 holding the coil in place 5 upon the core.

Secured to the top of the cage IB- is a plate 23, having upturned and outwardly extending cars 24 at its four corners, perforated to receive fulcrum pins 25 and 2B. The sides of the plate 23 10 have upturned extensions 21 which project through opening [4 of the housing and are provided with V-shaped notches 28 the bottom of which are slightly higher than the bottom of the V shapes [5 at the sides of the housing and-15 thus serve as a protection therefor. Imme diately adjacent and between the ears 24 at one end of the plate 23 are two down-turned lugs 29 to which is fastened a fibre plate 30 supporting in its center a make and break member 3| 20 having a contact pin32.

33 is a substantially rectangular plate having upturned lugs 34 at both sides near its top perforated to fit over fulcrum pin 25 and thus provide a swinging flapper having a pin 35 adapted 25 to contact with the contact point 32 of the make and break member 3| which is disposed between the flapper and the cage l8 of the coil. Angularly extending away from the plate 33 towards the opening l4 of the housing and between ex- 30 tensions 21 is a leg 36 being preferably an integral part of the plate. A substantially Z- shaped housing 31 on top'and at the end of the leg 36 is secured thereto, preferably by screws, and holding within it a sharpening member 38. The member 38, made of suitable abrasive material, is preferably flattened at its top and bottom at 39 to be securely held by the housing 31 on top of the leg 36, while its sides are slightly curved symmetrically at 40 and provided with 40 recesses 4|, so that projections 42 and recesses 4| alternate with each other, as clearly shown in Figs. 4 and 5.

Over the open end of cage I8 is disposed a rectangular plate 43, similar to plate 33 which 45 also similarly has upturned lugs 44 at both sides near its top perforated to fit over fulcrum pin 26 and thus provide a swinging armature at this end of the cage. Angularly extending away;

from the plate 43 towards the opening [4 of the 50 7 housing and between extensions 21 is a leg 45 being preferably an integral part of plate 43 and symmetrically disposed with respect to leg 36 of plate 33. To the end of the leg 45 is secured a housing 31 holding a sharpening member 33 6| "make and break member.

identical with one having correspondingly numbered parts fastened to leg 33. It will be noted that the two sharpening members engage each other so that projections 42 of one member extend into recesses 4| of the other member as shown in Fig. 4.

The bottom of plate 33 terminates in a hooklike extension 33a and the bottom of plate 43 in a similar extension 48a both of which are connected by a narrow strip 48. Support plate I6 is bent downwardly at right angles at lia to have fastened thereto one end of a retractile spring 41, the other end of which is fastened to extension 33a, thus urging the plate 33 towards the coil 2|. The support plate I8 is further extended towards the plate 43' at I61), and is provided with an opening I60 through which the extension 45a projects thus limiting its movement.

In the enlarged base portion ll of the housing ID are disposed two rows of standard battery cells 48. While in each row are shown two cells, this number may obviously be varied. A dividing strip 49 of insulating material is placed longitudinally across =the portion ll of the housing, separating the two rows of cells. 50 are metal springs riveted to-both sides of the strip 49, bent at right angles thereto near one of its extreme ends. These springs contact with the central electrode of one of the battery cells on one side and with the bottom of one of the cells on the other side of the strip thus electrically connecting the cells of adjacentrows in series,

as is shown in dotted lines in Fig. 3. BI is a flat' spring placed over the center of the strip 43 serving to keep the cells in position.

82 is a switch button through the top wall of the enlarged base portion ll 01 the housing l8, having an enlarged head 53 within the base, resting upon a flat spring member 84 which is fastened to the strip 49 near one end thereof opposite the one near which springs 50 are fastened. A spring 50a, similar to one of the springs 58,

is located immediately below spring member '54,

not in contact therewith, however, but adapted to'contact with the bottom of one of the battery cells in one row, while another similar spring b extends at the opposite side of the strip 49 to contact with the central electrode of one of the cells in the other row, the spring 53b being insulated from spring 501;. A portion of spring 88b is extended at 58c upwardly somewhat along strip 49, terminating below flat spring member 84 and normally in spaced relation therewith. Pressing down upon the switch button 52 forces the spring member 54 into contact with extension 580 of spring 50b, thus connecting electrically springs 50a. and 50b. Immediately upon releasing the pressure upon button 52, this electrical connection is broken.

The wiring diagram in Fig. 6 clearly illustrates the electrical connections and circuits. One end of the coil 2| is connected through the switch button 52 to spring 58b, cells 48 at one side, through springs 58 across the partition to the cells 48 at the other side, through spring 580 to the plate 33 and back to the coil through the The circuit is completed upon closing of the switch, by pressing the button 52, and is kept closed so long as the button is pressed down. v

With the switch closed, the armature 43 is drawn to the coil and assumes the position shown in Fig. 1, at the same time pushing the flapper plate 33 away from the coil to the position shown by virtue of the connection strip 48. In this extreme position of the flapper, contact is broken between the pin 38 and the contact point 32 of we make and break member 3| when the retractile spring 41 draws the flapper plate 5 towards the coil, while strip 48 forces the armature 43 away from the coil, until the armature reaches the limit of its travel away from the coil determined by contact of the extension 48a with the wall of the slot lie in support plate 10 extension lib. In that position, the flapper plate 33 is again contacting with the make and break member 3| and the circuit being thus again closed, the armature 43 is again drawn towards the coil and the cycle of operation re- 15 peated. Both the flapper plate 33 and the armature 43 being fulcrumed above the coil, this reciprocating movement is effected with very little power, and a rapid vibratory movement is set up. By shielding the coil 2|, as shown, ago

path is provided for the lines of magnetic flux coming from the core at the end nearest the flapper 33 to be carried back through the cage walls to the armature side of the coil, thus exposing the armature to the greatest possible as magnetic flux generally with a minimum of loss thereby increasing the power which is used to attract the armature toward the coil.

While the flapper plate 33 and the armature 43 are 'vibratorily reciprocated as Just now exso plained, he angularly extending

legs

33 and 48 of, respectively, these two members, are also reciprocated. Attention is particularly drawn to the fact that plate 33 and leg 36 are fulcrumed around pin 29, while armature 43 and leg 45 are fulcrumed around pin 26. Further, that while the armature 43 is moving towards the coil at the center of the sharpener, the plate '33 is moved away from it, and vice versa. By this means the extreme end of the leg 38 moves up- 46 wardly, while the extreme end of the leg 48 moves downwardly and the sharpening members 38 held within housings 31. at these extreme ends of the legs, are reciproeated past each other in 'an opposite direction in arcuate paths having 45 fulcrum pins 25 and 26, respectively, as their pivots. While the sharpening members are in such motion, the cutting edge of a knife to be sharpened is drawn across the oppositely disposed faces of the sharpening members, when 50 ber 38 are provided with the recesses and pro- 60 jections so that in case of wear, they can easily be turned around and the life of the members greatly increased. Attention is particularly drawn to the fact that the symmetrical shape of the, sharpening members make them invertible 65 as well as reversible i. e. they can be changed so that their points of contact with the knife can be varied to different positions, because they can be turned upside down and reversed laterally as well. The curvcd sides 40 are so shaped 70 as to form segments of a. circle of a diameter much greater than the distance between the opposite sides, whereby the abrasive action of the members is equal to that of wheels having each a radius the same as that of the curved 76 Drawing a knife in-this position a 55 sides 40 but occupying much less space. The flat top and bottom on the sharpening member serves the purpose of providing a good clamping surface for holding the member within the housing and against the leg to which the housing is fastened.

While we have shown a preferred form of the invention embodying its principles, we do not wish to limit ourselves to the precise arrange ment described and illustrated. We want it to be understood that various changes in the form, proportions and minor details may be resorted to without departing from the principles or sacrificing any of the advantages of the invention, as defined in the appended claims.

What we claim as new, is:

1. In a knife sharpener, sharpening members in juxta-positio'n to each other and in continuous contact with opposite sides of the same cutting edge of a knife placed between them, and

eleetro-magnetic means to move the said members alternately across said sides in arcuate paths, the paths having their axes substantially parallel to the. said edge.

2. In a knife sharpener, as defined in claim 1, wherein each sharpening member is provided with curved sides having alternately projections and recesses, the projections of one member fitting into the recesses of the other.

3. In a knife sharpener, as defined in claim 1, wherein each sharpening member is provided with a flat top and bottom and curved sides, one curved side of one member adapted to contact with one curved side of the other member.

4. In a knife sharpener, as defined in claim 1, wherein the sharpening members are invertible and reversible and provided with flat tops and bottoms and contacting curved sides.

5. In a knife sharpener, as defined in claim 1, wherein the sharpening members are invertible and reversible and provided with flat tops and bottoms and contacting curved sides, the sides having alternately interfitting projections and recesses. I

6. In a knife sharpener, an electro-magnet. an armature hingedly fastened to one side of the magnet in circuit, therewith and a flapper plate hingedly secured to the other side, the said armature and plate being connected to cause the one to move towards the magnet while the other moves away from it, a make and break member in the said circuit, sharpening members fastened, respectively, to the said armature and the said plate, and means to energize the said magnet causing vibratory reciprocating travels of the said armature and said plate for actuating the said sharpening members.

7. In a knife sharpener, as defined in claim 6, wherein the make and break member cooperates with the said flapper plate, the said make and break member being disposed between the said magnet and said plate, and a shielding cage surrounds the magnet on all sides except the one opposite the armature.

8. In a knife sharpener, as defined injclaim 6, wherein a shielding cage partially surrounds the 5 magnet, a retractile spring to draw the said plate towards the said cage and simultaneously move the said armature away therefrom, and means to limit the movement of the said armature. 1

9. In a knife sharpener, an electro-magnet, an armature hingedly fastened to one side ofthe magnet and a flapper plate hingedly secured to the other side, the said armature and plate being connected to cause the one to move 5 towards the magnet while the other moves away from it and each having a leg angularly disposed to each other, sharpening members carried by the said legs, a make and breakmember cooperating with the said flapper plate, and 20 means to energize the said magnet causing vibratory reciprocating travels of the said armature and plate, whereby the said sharpening members are given oscillatory motions in opposite directions adapted to sharpen the cutting edge of a 25 knife placed between them.

10. In a knife sharpener, a housing, an electromagnet within the housing, an armature hing-'- edly fastened to one side of the magnet and, a flapper plate hingedly secured to the other side, 30 a make and break member cooperating with the said flapper plate, the said armature and plate being connected to cause the one to move towards the magnet while the other moves away from it and each having a leg angularly dis- 5 posed to each other, sharpening members carried by the said legs, battery cells connected in series within the bottom of the housing, and means to energize the said magnet intermittently through the said make and break member 40 causing vibratory reciprocating travels of the said armature and plate, whereby the said sharpening members are given oscillatory motions in opposite directions to sharpen the cutting edge of a knife placed between them.

11. In a knife sharpener, a housing having a large bottom portion and a smaller top portion. and an opening at its top, sharpening members within the housing in juxtaposition to each other and at opposite sides of the same cutting 5 edge of a knife placed between them through the said opening, battery cells within the said bottom portion, an electro-magnet within the said smaller portion, a make and break member in the field of the said magnet, and means to 5 close an electric circuit between the magnet and the cells to oscillate the members simultaneously in opposite directions for sharpening the knife.

LOUIS c. HOBART. 6o KENNETH F. LEES.