US2795277A

US2795277A - Circular hole cutter

Info

Publication number: US2795277A
Application number: US400903A
Authority: US
Inventors: Edgar D Wortham
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-12-29
Filing date: 1953-12-29
Publication date: 1957-06-11
Anticipated expiration: 1974-06-11

Description

E. D. WORTHAM CIRCULAR HOLE CUTTER June 11, 1957 2 Sheets-Sheet 1 Filed Dec 29, 1953 A I INVENTOR. h/a/Zfifl Z77 ATTD R N EYE June 11, 1957 E. D. WORTHAM 2,795,277

CIRCULAR HOLE CUTTER.

Filedbec. 29, 1955 I 2 SheetsSheet 2 FIG. 7

) INVENTOR EDGAR D. WOR-THAM ATTORNEYS Uite This invention relates to manually actuated cutting tools particularly adapted for cutting openings for fire prevention in gasoline tanks, oil tanks, barges, ships and the like, and in particular a tool adapted to be temporarily installed from the outside of a tank or other vessel and having an arm with scribing and cutting elements thereon mounted on a bushing threaded on a center stud and in which the stud is provided with a head having a slot for a key or link extended therethrough whereby with the head inserted through and secured in an opening in a plate by the key and a lock nut, rotation of the arm with the cutting elements held in cutting relation with the plate by a spring on the bushing causes the cutting elements to cut a disc from the plate.

The purpose of this invention is to provide a manually actuated cutting tool that may readily be set up for operation from the outside of a tank or the like whereby openings may readily be cut in vertical walls of tanks and the like without cleaning or gas freeing and also wherein such openings may be cut in the least possible time.

With conventional methods of forming openings for fire prevention and the like in gas and oil tanks, barges, ships, and the like it is necessary to clean and gas free a tank before starting the cutting operation, and this requires from fifteen to twenty days. Also in cutting such openings with conventional methods there is a tremendous hazard, owing to the gas and oil fumes.

With this thought in mind this invention contemplates a cutting tool mounted on a threaded stud with the head of the stud adapted to be inserted through a bolt hole in the wall of a tank or the like and secured in said hole from the outside of the tank, and wherein the Cutting tool is carried by an arm having hand gripping handles on the ends rotatably mounted on the stud and having scribing and cutting elements adjustably mounted thereon and whereby with the head of the stud clamped in the opening upon rotation of the arm a spring forces the cutting elements into operative relation with either a flat or curved plate.

The object of this invention, is therefore, to provide a tool for cutting a circular opening in a plate, such as the wall of a tank in which the device may readily be mounted in an opening, such as a bolt hole in the wall of the tank.

Another object of the invention is to provide a manually, actuated cutting tool for forming circular openings in walls of tanks in which tension applied to cutting elements of the tool is readily adjustable.

Another important object of the invention is to provide a circle cutting tool having scribing and cutting elements carried by a stud temporarily mounted in an opening of a plate wherein the scribing cutter pushes and cuts and a cutting wheel pulls and cuts whereby with both the scribing arid cutting elements and cutting wheel working jointly a completely smooth and even cut is obtained in a fiat wall of a tank.

' atent A further object of the invention is to provide a hand actuated tool for cutting circular openings in circular walls of tanks and the like in which the tool is of a simple and economical construction.

With these and other objects and advantages in view the invention embodies an elongated threaded sud having a head with a transversely disposed slot therein, and a key slidably mounted and frictionally retained in said slot and adapted to be supported in an inclined position in the slot of the stud as the stud is inserted in an opening in a wall of a tank, and said key being adapted to be turned to a vertically disposed position, transversely of the stud, to prevent the stud being withdrawn through the opening whereby the stud is adapted to be used for mounting cutters for cutting an opening in a vertical wall'of a tank.

Other features and advantages of the invention will appear from the following description taken in connection with the drawing, wherein:

Figure 1 is a side elevational view of the improved circle cutting tool showing the device mounted on a plate, such as the vertical wall of a tank, the plate being shown in broken lines.

Figure 2 is a plan view of the tool, one of the arms of the tool being broken away.

Figure 3 is a vertical section through the tool taken on line 3-4) of Figure 1 showing the locking nut, bushing and elements mounted thereon and showing the stud in elevation, the lower end of the stud being broken away and a plate such as the vertical wall of a tank and upon which the device is positioned being shown in broken lines.-

Figure 4 is a detail showing the lower end of the stud, the upper part thereof being broken away and the stud being shown in a plate which is illustrated with broken lines.

Figure 5 is a section through the end of the stud taken on line 55 of Figure 4 illustrating the position of the locking key in the slot in the head of the stud and showing the parts in a vertical wall of a tank which is also illustrated in broken lines.

Figure 6 is a view looking upwardly toward the under surface of the locking washer positioned around the lower part of the stud.

Figure 7 is a view showing a section through a por-' tion of a tank and also through an end of a stud illustrating the inclined position of a key being inserted through an opening in a wall of a tank by the stud, the parts being shown on an enlarged scale.

Figure 8 is a view similar to that shown in Figure 7, showing the key retained in position by the curvature of one side at the lower end, and with the upper end held by the end of the stud.

Figure 9 is aview also similar to the views shown in Figures 7 and 8, showing the key drawn backward against the inner surface of the tank wall by the stud, and also showing the key in the position shown in Figure 8, in broken lines therein.

Although the cutter is shown as being used in a horizontal wall of a tank for the purpose of illustration, it will be understood that the device is used to cut circular openings in vertical walls of cylindrical tanks and particularlywith the opening spaced from the upper edge of the wall.

Referring now to the drawing wherein like reference characters denote corresponding parts the improved circular opening cutter of this invention includes an elon-i gated threaded stud 10 having a head 11 witha key 12 extended through a slot 13 therein, a locking washer positioned on the stud, a lock nut 15 threaded on the stud and positioned to clamp the washer 14 against one sur-f face of a plate or wall of a tank, as indicated by'th'e nu meral 16 with the key 12 in engagement with the opposite side of the wall, a bushing 17 having a flange 18 on one end also threaded on the stud and having a section 19 which is provided with flat sides, adjacent the outer end, an arm 20 having a hub 21 which extends over the bushing 17 and provides means for rotatably mounting the arm on the bushing, a spring 22 positioned around the bushing and extended between the hub 21 and a hub 23 of a hand actuated crank 24, a nut 25 threaded on a section 26 at the outer end of the bushing, a socket 27 for adjustably mounting a cutting wheel 28 on one side of the arm 20 and a socket 29 for adjustably mounting a scribing point 30 on the opposite end of the arm.

As illustrated in Figure 3, the head 11 of the elongated threaded stud 10 is adapted to be inserted through an opening, such as the opening 31 in a tank wall, such as the plate 16 and with the key 12 retained in an inclined position in the slot 13, as shown in Figures 7 and 8, and turned through an angle ,of 90 after being inserted through the opening the end portions of the key are adapted to be drawn against the corners of the plate with

fingers

32 and 33 on one side and 34 and 35 on the other side of the locking washer 14 straddling the key 12, as illustrated in Figure 4. By this means the key is retained in position and the locking nut 15, which is threaded on the stud 10 is turned until the key and washer 14 are positively clamped against opposite surfaces of the plate or wall 16.

The

sockets

27 and 29 are provided with openings through which the ends of the arm 20 extend and, as illustrated in Figure l, the socket27 is provided with a. set screw 36 by which the socket may be secured in adjusted positions on the arm. The socket 27 is also provided with a sleeve 37 having a set screw 38 therein and a stem 39 of a yoke 40 is secured in the sleeve 37 with the set screw whereby a cutting wheel 28, rotatably mounted in the yoke 40 with a pin 41 may be positionedto engage a tank wall, such as the plate 16, upon which the cutting tool is mounted.

The socket 29 is also provided with a set screw, such as the set screw 42 and a sleeve 43 extended from the hub 29 is provided with a bore 44 in which a point, such as the scribing point 30 may be held by a set screw 45.

By this means a scribing point may be set a predetermined distance from the center of the stud so that a circle may be described on the surface of a plate or wall of a tank or the like and with the cutting wheel 28 set to the same dimension the plate may be cut on the line described by the point 30.

The arm 20 is provided with graduations 46 on one side and 47 on the other and handles 48 and 49 are pro vided on the extended ends.

With the tool provided in this manner an opening, such as the opening 31 may be drilled through a plate or upper part of a vertical wall of a tank, and the head of the stud with the key 12 in the slot 13 thereof may be inserted through the opening and the parts assembled by first placing the washer 14 on the plate with the fingers straddling the adjacent side of the key 12 and this washer is secured in position with the lock nut 15 which also secures the stud in the wall. I

The bushing 17 is then threaded on the stud with the arm 20. spring 22 and hand crank 24 secured thereon by the lock nut 25 and with the scribing point and cutting wheel set to desired positions the arm is rotated whereby the cutting wheel cuts the plate. The spring 22 provides cushioning means relieving the cutting tool when the tool is fed too fast.

This cutter, which is completely installed and assembled from the outside of a tank, is designed whereby it will cut uniformly on a fiat surface and also on a curved surface such as the wall of a tank, and is particularly adapted for cutting openings for flanges from two inches to thirty inches in diameter without gas freeing the tank and also without the usual loss of time resulting from tying up the tank, barge, ship or the like.

The key 12 is machined to a close fit in the slot 13 and as the stud with the key in an inclined position therein passes through an opening in a tank wall, as shown in Figures 7 and 8, the lower end of the key rides upon the surface of the Wall at the lower edge of the opening therein, and the upper end is held by the end surface of the stud at the outer end of the slot. After passing through the opening in the wall the key is retained in position by the arcuate surface at the lower end resting upon the corner at the edge of the tank wall, and as soon as the key reaches this position the stud is drawn outwardly whereby the key is snapped to the positon shown in full lines in Figure 8.

It will be understood that modifications, within the scope of the appended claims, may be made in the design and arrangement of the parts without departing from the spirit of the invention.

What is claimed is:

1. In a circle cutting tool, the combination which comprises an elongated threaded stud having a head with a slot therethrough, a key positioned in the slot in the head of the stud, a locking washer having pairs of spaced fingers extended therefrom with the fingers positioned to straddle said key for retaining the key in the slot, a lock nut threaded on the stud and positioned to engage the washer, a bushing threaded on the stud, an arm having handles on extended ends thereof rotatably mounted on said bushing, a hand crank mounted on the bushing and adapted to rotate the bushing, a lock nut for securing the hand crank on the bushing, a scribing tool adjustably mounted on one end of the arm and a cutting wheel adjustably mounted on the opposite end of the arm.

2. In a eircule cutting tool, the combination which comprises an elongated threaded stud having a head with a slot therethrough, an open elliptical shaped key positioned in the slot in the head of the stud, a locking washer having pairs of spaced fingers extended therefrom with the fingers positioned to straddle said key for retaining the key in the slot, a lock nut threaded on the stud and positioned to engage the washer, a bushing threaded on the stud, an arm having handles on extended ends thereof rotatably mounted on said bushing, a hand crank mounted on the bushing and adapted to rotate the bushing, a spring on the bushing positioned to urge the arm away from the hand crank, a lock nut for securing the hand crank on the bushing, a scribing tool adjustably mounted on one end of the arm and a cutting wheel adjustably mounted on the opposite end of the arm.

3. A circle cutting tool comprising an elongated threaded stud, said stud having a transversely disposed slot in one end, a key the length of which is greater than the width frictionally retained in the slot of the stud, a washer having spaced pairs of fingers extended from one side mounted on the stud and positioned with the fingers adapted to straddle and frictionally engage said key, said fingers being positioned to retain the key in an inclined position in the slot of the stud as the stud is passed through an opening in a plate and to permit the key to be moved to a transversely disposed position to prevent withdrawal of the stud from an opening in a plate, an arm rotatably mounted on said stud, and a cutter carried by the arm and positioned to cut the plate upon rotation of said arm.

4. A circle cutting tool comprising an elongated threaded stud, said stud having a transversely disposed slot in one end, a key the length of which is greater than the width frictionally retained in the slot of the stud, a washer having spaced pairs of fingers extended from one side mounted on the stud and positioned with the fingers adapted to straddle and frictionally engage said key, said fingers being positioned to retain the key in an inclined position in the slot of the stud as the stud is passed through an opening in a wall of a tank and to permit the key to be moved to a transversely disposed position to prevent Withdrawal of the stud from an opening in a wall, an arm rotatably mounted on said stud, a scribing tool adjustably mounted on the arm, and a cutter adjustably mounted on the arm and positioned to cut the tank Wall upon rotation of the arm.

5. A circle cutting tool comprising an elongated threaded stud, said stud having a transversely disposed slot in one end, a key the length of which is greater than the width frictionally retained in the slot of the stud, a washer having spaced pairs of fingers extended from one side mounted on the stud and positioned with the fingers adapted to straddle and frictionally engage said key, said fingers being positioned to retain the key in an inclined position in the slot of the stud as the stud is passed through an opening in a Wall of a tank and to permit the key to be moved to a transversely disposed position to prevent withdrawal of the stud from an opening in a tank Wall, an arm rotatably mounted on said stud, a scribing tool adjustably mounted on the arm, a cutter adjustably mounted on the arm and positioned to cut the wall upon rotation of the arm, and resilient means for urging the arm and cutter toward the Wall.

6. A circle cutting tool comprising an elongated threaded stud, said stud having a transversely disposed slot in one end, a key the length of which is greater than the Width frictionally retained in the slot of the stud, a Washer having spaced pairs of fingers extended from one side mounted on the stud and positioned with the fingers adapted to straddle and frictionally engage said key, said fingers being positioned to retain the key in an inclined position in the slot of the stud as the stud is passed through an opening in a Wall of a tank and to permit the key to be moved to a transversely disposed position to prevent withdrawal of the stud from an opening in a wall, an arm ro-tatably mounted on said stud, a scribing tool adjustably mounted on the arm, a cutter adjustably mounted on the arm and positioned to cut the wall upon rotation of the arm, resilient means for urging the arm and cutter toward the wall, and means adjusting the tension of said resilient means.

References Cited in the file of this patent UNITED STATES PATENTS 127,934 Stone June 11, 1872 450,127 Wrigley Apr. 7, 1891 499,444 Schumann June 13, 1893 1,075,759 Burridge Oct. 14, 1913 1,527,763 Vance Feb. 24, 1925 1,537,376 Prosser May 12, 1925 1,966,962 Horhorouny July 17, 1934 1,971,701 Bills Aug. 28, 1934 2,230,400 Cadirola Feb. 4, 1941 FOREIGN PATENTS 595,608 France July 20, 1925 795,344 France Jan. 6,