US2658672A

US2658672A - Computing instrument for making elbows

Info

Publication number: US2658672A
Application number: US289966A
Authority: US
Inventors: Vernon W Dalzell
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-05-26
Filing date: 1952-05-26
Publication date: 1953-11-10
Anticipated expiration: 1970-11-10

Description

Nov. 10, 1953 v. w. DALZELL 2,658,672

COMPUTING INSTRUMENT FOR MAKING ELBOWS Filed May 26, 1952 A TTORNEYS Patented Nov. 10, 1953 OFFICE COMPUTING INSTRUMENT FOR MAKING ELBOWS Vernon W. Dalzell, Alliance, Ohio Application May 26, 1952, Serial No. 289,966

4 Claims. 1

The invention relates to a protractor particularly adapted for use in the making of elbows for determining the height of rise of the miter line.

An object of the invention is to provide a calculator by means of which elbows of two or more pieces or sections, for connecting two runs of pipe at any desired angle, may be easily and quickly made.

Another object is to provide such a device by means of which an elbow of any desired construction, for use upon pipe of any known diameter, may be quickly and easily constructed.

A further object is to provide such a device comprising two members pivotally connected together, the lower member having a straight upper edge and having spiral curved lines scribed thereon, the upper member having its upper edge graduated in inches or other units of measurement and having a perpendicular edge adjacent to the pivot point and located at 90 to said graduated edge.

A still further object is to provide such a calculator in which the several spiral curves upon the lower member indicate the number of pieces or sections of which the elbow is to be made.

The above objects together with others which will be apparent from the drawing and following description, or which may be later referred to, may be attained by constructing the improved calculator in the manner hereinafter described in detail and illustrated in the accompanying drawing, in which:

Fig. 1 is a top view of a calculator embodying the invention, showing the parts adjusted for the making of an elbow for connecting two runs of pipe located at a predetermined angle to each other;

Fig. 2 a diagrammatic view showing the manner in which the angle of offset of the two runs of pipe to each other is determined;

Fig. 3 a developed view of one section of an elbow showing the manner in which the pattern for the section is obtained from calculations made upon the calculator;

Fig. 4 a side elevation of an elbow which may be constructed by use of the calculator; and,

Fig. 5 a diagram showing the manner in which the spiral curve may be plotted by the coordinate system.

Referring first to the calculator illustrated in Fig. 1, the device may be formed of two members comprising the lower plate, indicated generally at it), and the upper plate, indicated at I I, both of which may be formed of any suitable material, preferably a transparent plastic material, such as 2 is ordinarily used for the making of draftsmens triangles and the like.

The lower member H! has the straight upper edge l2 and one perpendicular edge [3 at right angles to the straight edge l2. The upper member I has the graduated top edge [4, which may be graduated in inches as shown, or may have metric system graduations thereon, if desired.

This upper member has the perpendicular edge !5 located at to the graduated edge l4, and is pivotally connected to the lower member ID at the upper left hand corner thereof, as by the pivot screw i5 upon which is located a nut I! for locking the two members in any desired adjusted position.

The lower member I6 has a calculator formed thereon comprising a plurality of equally spaced radial lines, radiating from the pivot point 16 and extending from the vertical line indicated at 0 to the horizontal line indicated at 90, or even greater angles.

The particular embodiment of the calculator illustrated is a 10 inch size, being especially adapted for use in obtaining the measurements for sections of an elbow for use with a 10 inch diameter pipe.

It should be understood that the calculator may be made in various sizes, for various other diameters of pipe, although, as will be later described in detail, the measurements for elbows to fit other diameters of pipe may be quickly and easily computed from this 10 inch size calculator.

A spiral, curved line H! is scribed upon the top surface of the lower member ll}, extending from the pivot point IE to the point where it intersects the horizontal 99 radial line [9 at a point exactly 10 inches from the pivot point.

In Fig. 5 is shown a diagram indicating the manner in which this spiral curved line l8 may be determined by the coordinate system. It should be understood that this diagram is shown on a much smaller scale than the calculator in Fig. 1, being one-fourth the size thereof.

In plotting this curve by the coordinate system the initial line 26 is drawn of a length exactly twice the diameter of the pipe for which the calculator is designed, in the present case the line 20 being 20 inches long.

At the exact center of the line 2|] the origin or pole 2! is located and with this center the semicircular arc 22 is drawn connecting at opposite ends with the ends of the initial line 20.

A plurality of radius vectors, as indicated at 23, are drawn from the pole 21 to the are 22, being preferably located at angles of 5 to each other throughout the entire arc. vertical radius vector 23c, indicated at the radius vectors to the left thereof are indicated at to 90, and starting at the right of the radius vector 23a. they are indicated reversely from 85 to 0.

At the point of intersection of the initial line with the left side of the arc 22 is formed a secondary pole 24, from which secondary vectors, as indicated at 25, radiate and intersect the are 22 at the points of intersection therewith of the radius vectors 23 indicated at 85 to 0 on the right side of the arc.

The points 26, at which the secondary vectors 25 intersect the radius vectors 23 of like number, determine the spiral curve is which is then drawn through the points 2%. This spiral curved line 18 upon the calculator, as shown in Fig. 1, is used in conjunction with the graduated edge M of the top member l l to determine the height of rise of the miter line where a two-piece or two-section, elbow is to be made.

Similar spiral curved lines indicated at 2?, 28, 29, 38, 3!, 32 and ('33 are scribed upon the top surface of the lower member to for use in determining the rise of the miter line where 3, l, 5, 6, '7, 8 or 9 sections respectively are to be produced for making the elbow.

In using the improved calculator for making an elbow, it is first necessary to determine the angle of oiTset between the two runs of pipe to be connected. This may be done as indicated in the diagram of Fig. 2 in which the lines and 34 indicate the two runs of pipe to be connected.

The straight edge 52 of the lower member it of the calculator may be placed against the line 34 and the upper member ll of the protractor swung upon the pivot point it until the per pendicular edge IE3 or" said upper member is lined up with the line 33. This locates the graduated edge 14 of the upper member l l at a 69 angle as indicated on the calculator shown in Fig. 1.

Another way to determine this setting of the calculator is to extend the line 33 above the line 34 as indicated in dotted lines at 33a in 2, and then measure the angle between the line 34 and the extension 33a which is shown to be 60. The upper member ll of the calculator is then moved to the 60 position as shown in Fig. l.

The workman then decides whether to make the elbow in two or more sections. If he is to make the elbow of two sections he then takes the reading upon the graduated edge M where the same intersects the spiral curved line l8, which as shown on Fig. l, is 5% inches. This is the height of rise of the miter line for a twopiece elbow.

Assuming that the workman decides to make the elbow of three sections, he takes a reading upon the graduated edge id or" the upper member at the point where it intersects the spiral curved line 21 which, as shown on Fig. 1, is about 2%;- inches. This is the height of rise of the miter line for the first section of the three-piece elbow.

To lay out this section of the elbow the workman then draws a circle as indicated at 35 in Fig. 3, the diameter of which is 2%},- inches. He then draws a horizontal line, as indicated at 36 in Fig. 3, at any distance below the circle 35 which may be desired for additional length in the section for telescoping with the adjacent end of one run of the pipe.

A vertical line Si is drawn through the center of the circle 35, perpendicular with the hori- Starting with they zontal line 36. This vertical line forms the center of the pattern for this section of the elbow. The horizontal line 36 is extended an equal distance to each side of this center, the length of the horizontal line from the points 33 to 35) being equal to the circumference of the section of the elbow.

The circle is then divided into 12 equal parts as indicated by the radial lines 49, and the horizontal line 35 is divided into 12 equal parts, as indicated by the vertical lines 4i. Horizontal lines 42 are then drawn through the radial division 40 of the circle and intersect the vertical lines 4|.

A curved line 44 is then drawn through the points of intersection 43 of the vertical and

horizontal lines

41 and 42 respectively, and this curve will be the upper edge of this section of the elbow.

As shown in Fig. 4 this section of the elbow is shown in side elevation at 45. The maximum height 48 of the middle section 4? of this elbow will be twice the maximum height 43 of the section 45, or twice the height of rise of the miter line plus any additional length desired to give the proper center line radius. The third section 49 of the elbow will be the same as the section 45, plus any additional length which may be desired for telescoping with the pipe.

It will thus be seen that with this improved angle protractor an elbow of any desired number of sections for connecting together two runs of pipe located at any angle to each other may be quickly and easily plotted.

The above description has reference to the making of an elbow for a pipe of 10 inches in diameter. If elbows are to be made for pipes of smaller or larger diameter the calculator may be made in such smaller or larger sizes as may be required.

However, by using the 10 inch calculator as illustrated, measurements may be quickly computed for the making of elbows of larger or small er diameter. For instance, in the event that an elbow is to be made for a 5 inch pipe, the reading upon the graduated edge 14 of the upper member of the calculator, where the same intersects any one of the curved lines it or 2'1 to 33, may be divided by 2.

For instance, if a three-section 50 elbow is to be made for a 5 inch diameter pipe, the reading of 2%,- inches will be divided by 2, the height of rise of the miter line being 1 inches.

If an 8 inch diameter elbow is to be made, fourfifths or .8 of the reading upon the graduated edge l 4 will be taken as the height of rise of the miter line, etc.

If, on the other hand, a larger diameter pipe is used, the reading upon the graduated edge of the upper member of the calculator may be added to. For instance, assuming that an elbow is to be made for a 12 inch diameter pipe the height of rise of the miter line will be 1 or 1.2 times the reading upon the graduated edge l4, etc.

Although the protractor is shown as designed for making an elbow for connecting two runs of pipe located at an obtuse angle to each other, it will be possible with the same type of calculator to design an elbow for connecting two runs of pipe at an acute angle to each other. This may be accomplished by increasing the height of the lower member in of the protractor so as to project the curved lines is and 21 to 33 beyond to a maximum of approximately In the foregoing description, certain terms have been used for brevity, clearness and understanding, but no unnecessary limitations are to be implied therefrom beyond the requirements of the prior art, because such words are used for descriptive purposes herein and are intended to be broadly construed.

Moreover, the embodiments of the improved construction illustrated and described herein are by way of example, and the scope of the present invention is not limited to the exact details of construction.

Having now described the invention or discovery, the construction, the operation, and use of preferred embodiments thereof, and the advantageous new and useful results obtained thereby; the new and useful construction, and reasonable mechanical equivalents thereof obvious to those skilled in the art, are set forth in the appended claims.

I claim:

1. A device for determining the height of rise of the miter line for making elbows, said device comprising a lower member, an upper member having a straight edge graduated with a scale of linear measurements thereon, means pivoting the end of the upper member to one end of the lower member, there being a spiral curved line on the lower member extending from the pivot point toward the other end thereof and indicating an elbow having a definite number of sections, whereby in a predetermined relative position of the upper member upon the lower member the point of intersection of the graduated edge of the upper member with the spiral curved line on the lower member indicates the height of rise of the miter line for a particular elbow formed of a predetermined number of sections.

2. A device for determining the height of rise of the miter line for making elbows, said device comprising a lower member, an upper member having a straight edge graduated with a scale of linear measurements thereon, means pivoting the end of the upper member to one end of the lower member, there being a spiral curved line on the lower member extending from the pivot point toward the other end thereof, said spiral curved line being plotted by the coordinate system and indicating an elbow having a definite number of sections, whereby in a predetermined relative position of the upper member upon the lower member the point of intersection of the graduated edge of the upper member with the spiral curved line on the lower member indicates the height of rise of the miter line for a particular elbow formed of a predetermined number of sections.

3. A device for determining the height of rise of the miter line for making elbows, said device comprising a. lower member, an upper member having a straight edge graduated with a scale of linear measurements thereon, means pivoting the end of the upper member to one end of the lower member, there being a plurality of spiral curved lines on the lower member extending from the pivot point toward the other end thereof and indicating a plurality of elbows each having a definite number of sections, whereby in a predetermined relative position of the upper member upon the lower member the point of intersection of the graduated edge of the upper member with any spiral curved line on the lower member indicates the height of rise of the miter line for a particular elbow formed of a predetermined number of sections.

4. A device for determining the height of rise of the miter line for making elbows, said device comprising a lower member, an upper member having a straight edge graduated with a scale of linear measurements thereon, means pivoting the end of the upper member to one end of the lower member, there being a plurality of spiral curved lines on the lower member extending from the pivot point toward the other end thereof, said spiral curved lines being plotted by the coordinate system and indicating a plurality of elbows each having a definite number of sections, whereby in a predetermined relative position of the upper member upon the lower member the point of intersection of the graduated edge of the upper member with any spiral curved line on the lower member indicates the height of rise of the miter line for a particular elbow formed of a predetermined number of sections.

VERNON W. DALZELL.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,042,360 Maguire Oct. 22, 1912 2,361,807 Wolfe Oct. 31, 1944 2,405,113 Clemons Aug. 6, 1946 2,551,997 Cody May 8, 1951 2,562,224 Weyrick July 31, 1951