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Publication numberUS2023539 A
Publication typeGrant
Publication dateDec 10, 1935
Filing dateOct 20, 1933
Priority dateOct 20, 1933
Publication numberUS 2023539 A, US 2023539A, US-A-2023539, US2023539 A, US2023539A
InventorsFrancis M Packard
Original AssigneeFrancis M Packard
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Roof pitch indicator
US 2023539 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

Dec. 10, 1935. F. M. PACKARD 2,023,539

ROOF PITCH INDICATOR Filed Oct. 20, 1955 FIG 1 l B mnmw M ATTORNEY.

Patented Dec. 10, 1935 UNITED STATES @ATENT OFFIQE ROOF PITCH INDICATOR Francis M. Packard, Davenport, Iowa Application October 20, 1933, Serial No. 694,497 1 Claim. (01. 33-75) My invention has reference to an instrument for indicating the pitch of a roof, and making various computations in connection therewith. By its use it is possible to make an estimate of the pitch or" a roof from the ground, to compute the length of the rafters, and the area of the roof. It is of special advantage in determining the amount of roofing material required for replacing an old roof. At the present time the only method for doing this which is in practice is to go upon the roof and make the necessary measurements.

The instrument consists or" a pair of arms pivotaily attached to each other, and provided with a head on one of said arms having graduated tables, and a disk on the other arm provided with indicators for use in making readings on said tables. The arms are also provided with tables pertaining to the general roof characteristics, and various data for use in making the desired computations. The character of the device is such that it can be used as a sight instrument initially in determining the pitch of a roof at a little distance therefrom. By the use of the tables mentioned it is also possible to set the instrument for use in making plumb cuts of rafters and other cuts on lumber going into a roof. The tables on the arms of the instrument are of a four-fold character, making it possible to include therein data for roofs varying from a three-inch pitch to a twenty-four-inch pitch.

Another feature of the invention consists in a protractor table on the head of the instrument, which can be used independently of the other tables for securing various angles, and can also be used in connection with said other tables in making computations or verifying the same.

Another advantage of the invention consists in the facility with which it can be folded into a small space, for carrying in the pocket or in a tool box. It also possesses advantages as an advertising medium, being provided with spaces which can be used for commercial cards.

The above named, and other features and advantages of the invention will more fully appear from the following specification, taken in connection with the accompanying drawing, in which:

Fig. 1 is a plan view, showing the invention with the arms of the tool in angular relation, as when in use.

Fig. 2 shows the same with the arms describing a smaller angle, as when a larger angle is bi sected for laying out a plumb-cut of a rafter.

Fig. 3 is a fractional view of the head 6, showing the plumb-cut scale, enlarged.

The instrument consists of an arm 5, provided at one end with a head 6 of circular form, and a similar arm 1, provided at one end with a disk 8, pivotally connected with the head 6 by a rivet 9, so that said head and disk have a frictional engagement with each other. The edges 80 and I! {g of the arm 5 are in parallel relation with each other, and can be used as straight edges, and the edge it is in line with the pivot 9. The edges l2 and E3 of the arm i are also in parallel relation with each other, and the edge 53 is in line with 3} said pivot. The diameter of the disk 8 is less than that of the head 6, the space on the projecting portion of the head being utilized for tables of graduated scales, as is hereinafter more fully set forth. l5 The arms 5 and l are shown provided with four tables of numbers, as at A, B, C, and D, each table being formed of columns of spaces transversely of the arms, as noted at a, b, c, d, e, f, and g, the columns being repeated in the several tables, so 20 as to allow for the listing of a number of variations in roof pitches and other designations. Said columns are subdivided by longitudinal lines into spaces for the numbers, and are variously designated at the heads of the columns. The 25 first of said columns is marked Rise per foot run, which is indicative of the pitch of a roof, and the second column gives the roof pitch as commonly termed. For instance, in Table C, in the last space the rise per foot run is given as 30 18 inches, and in the second column it is set forth as a three-fourths pitch. On the head 6 at E is a table provided with markings corresponding with the various pitches, readable by means of a pointer M on the edge of the disk 8, and show- 35 ing that the angular inclination of the arms 5 and '5 corresponds with the pitch of a roof. These markings correspond with the figures in column a of the tables, and these are the key figures upon which various deductions and computations may 40 be made.

If it is desired to find the pitch of a roof from the outside of a building the instrument is held by the operator with the ends of the arms pointed downwardly while the operator sights at the gable 45 end of the roof along the inner edges of said arms, and moves the same until they correspond in position with the edges of the roof. 'Lhe degree of variation of the arms as well as the pitch of the roof is thereupon indicated by the pointer M on the scale E, which is shown in the drawing set for a 14 inch pitch. This is then used as a basis for making desired computations. The head 6 is also provided with a protractor scale F, to be used in connection with a pointer I5 on the edge of the disk 8.

The arms 5 and l are rotatable in adjacent planes, so that said blades can be made to cross over each other, and when in a normally folded position the edges IE! and I3 are adjacent to each other and the edges l I and I2 on the outside, and parallel with each other. For sighting purposes the arms are crossed over, as in Fig. 1, with the edges H and 12 on the inside and forming a complete angle, which can be varied to form any acute or obtuse angle. The edges 60 and I3 can not be used for forming a sight ing angle, on account of obstructions near the inner ends thereof.

After finding the pitch of a roof in the manner hereinbefore set forth the length of a common rafter in such roof may be determined by the use of measurements contained in column d of the tables on the arms. This is done by measuring the width of the building including cornices, and multiplying one-half of this dimension by the number in said column which is in line withthe pitch indicated. For example, assuming the width of the building to be twenty-eight feet including the cornices, one-half of this amount, if for a 14 inch pitch, is multiplied by 1.536, giving the length of the rafter as approximately 21.5 feet.

In case the roofing on such roof is to be replaced, and it is desired to find the area of the roof, this is done by multiplying the width of the building by the length of such building, including the cornices, and adding to the amount thus attained a percentage thereof, as contained in column e. For example, assuming the building to be the same width as given above, and the length thereof forty feet, the forty is multiplied by the 28, giving as a'result 1120 square feet, and if the pitch of the roof is 14 inches, this amount has added thereto fifty-four per cent of said amount, or 604.8 square feet. This amount is then added to the original amount, giving the sum of 1725 square feet, the total area of the roof. In this computation no allowance is made for waste.

A similar computation to that given above for a common rafter may be made for obtaining the length of a hip or valley rafter, by the use of figures in column 1 of the tables. For a building of the same width as before given and having a 12 inch pitch, one half of the width is multiplied by 1.83, giving a rafter length of 24.22 feet. The same result may be obtained by adding to the length of a common rafter for the same roof a percentage as shown in column 9. In the case of a 12 inch pitch this is 22 per cent. In making any measurement of rafters there is no allowance for plumb cuts thereof.

In the case of a building under construction the computations hereinbefore mentioned can be made and the rafters and roofing material cut to desired dimensions before taking them on the building. The instrument can also be used for making markings on the rafters for making miter cuts thereon, such as a plumb cut at the upper end of a rafter and a heel-cut at the lower end. For both of these operations the scale F may be employed, and in addition thereto a scale G on the head 6. readable with an arrow I 6 on the disk 8. The divisions on said scale are shown numbered from 1 to 24, and they coincide in position with about sixty degrees of thelprotractor scale. They also correspond with the roof scale numbers in the tables on the arms. The setting of the tool is made in accordance with the data contained in column of the tables, which are marked for degrees on the scale F, and constantly increasing as the pitch increases.

In establishing the position of the arms for a heel-cut marking the pointer 15 is made use of, and with the markings at the lower end of the scale F. For a 14. inch rise the indication in column c is approximately 49 degrees, and the pointer is set at this point on the scale, giving the desired angle to the arms. The marking is then done by placing the inner edge of one of said arms against the edge of the timber and using the adjacent edge of the other arm as a straightedge, for marking across the face of the timber.

For a plumb-cut marking the indicator I6 is used, with the degrees at the upper end of the scale. The positions of the degrees on the scale should be reversed for this reading, but the desired result is obtained by subtracting the number of degrees shown in column 0 from the total number of the degrees, and using the remaining figure as a gauge for the indicator. For example, in the 14 inch pitch, the table gives a setting of approximately 50 degreea'and this amount is deducted from 180, leaving 130 as the point for locating the indicator. When at this point the indicator will also be in line with the number 14 on the scale G. The setting of the indicator on thescale G is thereby verified by the degree marking on the scale F, and this will be the case with all of the markings on the scale G.

The markings on the scale G are on a larger circumference and have smaller divisions, making it possible to make finer settings than on the scale F alone. When the angle has been 3 established the instrument is set against the rafter as before, and in position to make a miter marking in the opposite direction, and at substantially right angles with the heel-cut marking.

The device can also be used for finding the 40.

angle of an object of angular formation by fitting the inner edges of the arms 5 and 1 against the object and noting the degree of separation of the arms on the scale F.

The arms are shown extended beyond the table 45. markings for convenience in handling, with spaces l8 at the ends for reading matter, such 'as instructions for using the instrument or for advertising cards. The reverse faces of said arms can also be made use of for similar purposes. 50.

The instrument is preferably formed of celluloid with the various markings stamped or printed thereon, and the arms can be folded into parall'el relation as shown in broken lines in Fig.

1, for convenience in carrying in the pocket or other receptacle. Other material than that mentioned can be used in the construction of the device, and changes can be made in the arrangement'of the various scales and tables without departing from the general purpose thereof.

What I claim, anddesire to secure by Letters Patent, is:

A roof pitch indicator comprised of a pair of arms pivotally united at their ends and rotatable in adjacent planes, having a pair of edges in line with the pivotal point, and a pair of straight edges parallel with the first-named edges, said arms being foldable to bring the last-named edges into parallel relation with each other, and

also movable to cause said last-named edges to form a perfect angle, and cooperating means on said arms for indicating the degree or roof pitch shown by said angle.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2520934 *Nov 19, 1947Sep 5, 1950Hoy Rolland CAircraft control surface rigging protractor
US2529640 *May 28, 1945Nov 14, 1950William ThomasDesk or pocket bevel
US2641842 *Nov 2, 1951Jun 16, 1953Us Rubber CoMeasuring instrument
US2676511 *Aug 22, 1950Apr 27, 1954Weisse Ernst EDrawing instrument
US2899749 *Sep 16, 1955Aug 18, 1959 Movable graduator
US3096586 *Mar 25, 1955Jul 9, 1963Albright William RLayout gauge
US4097999 *Jan 3, 1977Jul 4, 1978Nowlin William EAngle gauge
US6314652May 10, 1999Nov 13, 2001Versa Technologies, Inc.Multi-purpose, multi-functional tool
US7335167 *May 12, 2005Feb 26, 2008Patrick MummyPosture realignment system
US20080120852 *Nov 29, 2006May 29, 2008Jeffrey RamseyRoof pitch gauge
U.S. Classification33/423
International ClassificationG01B3/56
Cooperative ClassificationG01B3/56
European ClassificationG01B3/56