US2851009A - Lead pointer - Google Patents

Description

Sept. 9, 1958 l.. BRANvoLD 2,851,009

LEAD POINTER 2 Sheets-Sheet 1 Filed Sept. 15, 1955 Leonard Bram/old uvm/TOR.

BY WWWH-Mm Sept 9 1958 L. BRANvoLD 2,851-,0'09

LEAD POINTER Filed sept. 15. 195:5 l 2 sheets-sheet 2 'i I. l l

a lit. 7

Leonard Branvo/d INVENTOR. 1

Wwzfmm LEAD PQHNTER Leonard Branvold, Sun Valley, Calif., assigner of twentyfive percent to Raymond L. Smack, Wilmington, tCalif.

ppiication September 15, 1953, Serial No. 380,227 1 Claim. (Cl. 1Z0-96) This invention relates to a lead pointer and more specically provides an electrically operated lead pointer for automatically sharpening the lead point of a draftsmans pencil to a perfect and accurate conical point.

An object of this invention is to provide a lead pointer having a novel construction wherein the lead is sharpened without the necessity of moving the lead pencil or lead holder during the sharpening process.

Another object of this invention is to provide a lead pointer having a novel switch wherein the sharpening operation may be carried out by the use of only one hand wherein the switch is a part of the lead receiving opening and the lead point need not be rotated or moved during the sharpening process.

A vfurther object of this invention is to provide a lead pointer having an abrasive member which rotates on an eccentric member thereby moving about the pencil lead and grinding the lead evenly about its entire periphery.

A still further object of this invention is to provide a lead pointer having an abrasive sharpening member and a novel driving arrangement for the abrasive member.

Yet another object of this invention is to provide a lead pointer which is simple in construction, easy in operation, inexpensive to manufacture and well adapted for the purposes intended.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a perspective view of the lead pointer of this invention showing the lead point insert socket;

Figure 2 is a transverse vertical section taken substantially along the center line of the lead pointer of Figure l showing details of the electric motor and abrasive member and its drive means;

Figure 3 is a detail, sectional view showing the switch actuator and the abrasive member with its drive means;

Figure 4 is a top plan viewvshowing the abrasive member and its drive means;

Figure 5 is a transverse, vertical section taken substantially along the same plane as the lead pointer of Figure 2, showing details of a modified form of abrasive member and its modified driving means;

Figure 6 is a top plan section showing details of the modified abrasive member and drive means;

Figure 7 is a transverse, vertical section taken substantially along the same plane of the lead pointer as Figure 5 showing another modified form of abrasive means and its drive means;

Figure 8 is a top plan section similar to Figure 6 showing detaiis of the modified drive means of Figure 7; and

Figure 9 is a detail view of a modified access opening used in conjunction with the abrasive member of Figure 5.

Referring now specifically to Figure l, it will be seen arent Q ice 2 that numeral 10 generally designates the lead pointer of this invention, having a lower housing member 12 and an upper housing member 14 with a suitable insert socket 16 on the upper housing 14 for insertion o-f a lead point to be sharpened.

Now referring specifically to the device as illustrated in Figure 2-5, it will be seen that an electric motor 18 is positioned in the lower housing 12 by suitable fastening means 20 and is actuated by a suitable electric circuit 22. The electric motor 18 drives a shaft 24 having a circular plate 26 mounted thereon and rotatable therewith. A vertical pin 28 is mounted in the plate 26 at a point spaced from the center of the shaft 24 and rigidly secured to the plate 26. Freely rotatable about the vertical pin 28 is a hollow frusto-conical member 30 having an abrasive surface 32 on its inner surface for engaging a lead point which may be inserted in the socket member 16 which has an elongated bore 34 and an opening 36 for guiding the lead point into engagement with the abrasive surface 32. As best seen in Figure 3, the upper end of the socket 16 has an outwardly projecting flange 38 for retaining a slidable sleeve 40 about the periphery of the socket 16. The tubular sleeve 40 is vertically slidable on the socket 16 and is held in its upward position by a compression spring 42 and one edge of the tubular sleeve 46 engages a spring 44 having an electrical point 46 thereon for engaging with a mating point 48 thereby closing the electrical circuit 22 for actuating the motor 1S. When the person inserts the lead point into the socket 16, he may employ the use of a single finger to actuate the sleeve 48 for closing the circuit 22 and actuating the motor 18 and the abrasive member 32. As best seen in Figure 2, the conical member 30 has a rod 50 secured adjacent its bottom end and passing horizontally across the housing 14 into an upstanding lug 52 having a suitable bore therein for receiving the end of the rod 50 and'precluding ro-k tation of they conical member Stfrelative to the housing 14. As the motor 18, shaft 24, and plate 26 are rotated, it will be seen that the vertical pin 28 moves in a circular path and necessarily carries the conical member and the abrasive surface 32 in a circular path about the axis of the shaft 24. The rod 50 has a mutating movement and retains the conical member from rotating in relation to the housing thereby assuring an abrasive action to a lead point in engagement with the abrasive surface 32. A counterbalance member 54 is secured to the plate 26 opposite the pin member 28 for offsetting the weight of the pin 28 and the conical member 30 thereby affording a smooth and eiiicient operation.

Now referring specifically to the modification of the lead pointer as illustrated in Figures 5, 6 and 9, it will be noted that the electric motor 18 and the electric circuit therefor and switch means is identical to the device of Figure 2. The drive shaft 24 has a small sun gear 56 thereon in meshing engagement with a movable gear 58 which is freely rotatable in a plate 60 which is freely rotatable in a stationary member 62 which is supported on the motor 18 by spacers 64. An internal gear 66 is secured to and spaced upwardly from the stationary plate 62 and the movable gear 58 is in rneashing engagement therewith. A hollow conical member 68, having an abrasive surface on the inner surface thereof, is positioned on said movable gear 58 and frictionally held thereon by a spiral compression vspring 72 engaging a flange 74 on a pivot pin 76 thereby holding the bottom of the conical member 68 against the upper surface of the movable gear 58. Obviously, the socket 16 may be modified to receive an ordinary type lead pencil 78 as well as the type having the lengthy projection of lead such as shown projects through the aperture 36.

Referring now specifically to Figures 7 and 8, it will be seen that the socket 16 has a bore 78 which is the same cross section throughout its length. The drive shaft 24 has a plate 80 secured thereto and rotatable therewith and a pair of gears 82 are moved therewith and rotate relative thereto on pivot members 84. A stationary internal gear 86 is in meshing engagement with the gears 82 and conical members 88 having an outer abrasive surface 90 which are secured to the pivot pin 84 and rotatable therewith. Gears 82 move about the internal gear 86 thereby rotating the pivot axle 84 and the abrasive member 90 thereby sharpening a lead point which is inserted therebetween. It will be noted that one of the conical members 88 is positioned above the other for assuring an accurate, needle-like point. Y

The operation of the devices will be readily understood. A lead point or pencil is inserted in the socket 16 and the tubular sleeve 40 is moved downwardly bringing the points 46 and 48 into contact thereby completing the electric circuit and driving the motor. Through the various driving means and modifications of the abrasive members, the lead point will be sharpened by the rotation of the abrasive members on an eccentric about the lead pencil thereby sharpening the point without rotation of the pencil or movement of any kind, and it will be noted that each point may be sharpened by means of only a single hand thereby saving time for economical operations.

From the Iforegoing, the construction and operation of the device will be readily understood and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claim.

What is claimed as new is as follows:

A lead pointer comprising a hollow rigid housing, a tubular member extending through the housing with the bore of the tubular member forming a lead receiving socket, an electric motor mounted within said housing, a drive shaft on said motor, a plate rigid with said drive shaft, an upstanding pin mounted eccentrically on said plate, a frusto-conical abrading member journalled on said pin, said abrading member having an inclined abrasive surface for engagement with the end of a lead disposed in the socket, a pin extending from and rigid with the abrading member, means slidably and pivotally connecting the free end of the pin with the housing for preventing relative rotation between the abrading member and the housing and permitting the abrading member to evolve with the plate and rotate on the pin, an electric circuit connected with the motor -for supplying energy thereto, a switch disposed in said circuit, said housing having a recess surrounding the tubular member and eX- tending inwardly from the outer surface of the housing, a sleeve slidably mounted on said tubular member, a spring disposed between the inner end of the sleeve and the bottom of the recess for urging the sleeve outwardly a flange on the outer end of the tubular member for limiting the outward movement of the sleeve, said flange overlying only a portion of the outer end of the sleeve for permitting finger engagement with the sleeve, said switch including a pair of relatively movable contacts spring urged apart disposed in said recess in the path of movement of the sleeve whereby inward movement of the sleeve will close the switch and energize the motor thus permitting operation of the lead pointer by the same hand that is employed `for holding the lead in the socket.

References Cited in the tile of this patent UNlTED STATES PATENTS 1,776,965 Bruss Sept. 30, 1930 2,184,176 Blake Dec. 19, 1939 2,189,476 Sggelko Feb. 6, 1940 2,233,681 Swanson Mar. 4, 1941 2,545,779 Harrison Mar. 20, 1951 2,649,552 Burrell et al Aug. 18, 1953 FOREIGN PATENTS 273,979 Switzerland Mar. 15, 1951 135,541 Sweden Apr. 29, 1952

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