Level and angle attachment for a carpenter's folding ruler

An attachment for a carpenter's folding ruler has an elongated body with a longitudinal slot. The slot is dimensioned to accept the ruler and the ends of the body have flat sections against which part of the ruler can be folded to form certain angles. One of the ends makes a 90.degree. angle with the axis of the slot while the other end is at some angle less than 90.degree.. A level is provided on the body so that it may be vertically or horizontally positioned.

BACKGROUND OF THE INVENTION 
This invention relates to devices for leveling objects, setting objects at 
some angle with respect to level and cutting angular shapes in work 
pieces, and, more particularly, to combination level and angle devices. 
Combination level, try-square and plumb devices which have a protractor or 
some other angle setting means, arranged to establish an angular 
relationship between two pivoting members of the device, and a level 
located in one of the members, are known from the prior art. For example, 
U.S. Pat. No. 3,945,301 to Peterson and U.S. Pat. No. 2,878,569 to 
Metrulis show such a device. Such devices, however, are separate tools and 
are not adapted to be inexpensive attachments to devices that the workmen 
already has, e.g., a folding ruler. 
An attachment for a folding ruler is shown in U.S. Pat. No. 2,720,705 to 
Vincent. This arrangement has a plumb bob so that when the folding ruler 
is extended it may be leveled. Also, the attachment may be set at 
predetermined angles with respect to the ruler so that when the plumb bob 
indicates level, the ruler will be at a fixed slope with respect to the 
horizontal. The ruler itself, however, is not folded to form some angle 
and therefore, it cannot be used to draw a simple complete angle on a work 
piece with one adjustment. Rather one side of the angle is drawn and then 
the attachment must be readjusted to draw the other side. 
U.S. Pat. No. 389,647 to Hall et al. and U.S. Pat. No. 1,061,045 to 
Campbell show devices with particular angularly arranged members and a 
level so that slopes can be drawn. These devices are attached to a folding 
ruler, but the ruler only acts as a holder and is not folded to form an 
angle. 
It would be advantageous if a simple inexpensive device were available 
which could be attached to a folding ruler so that it can be leveled and 
folded at particular angles. 
SUMMARY OF THE INVENTION 
The present invention is directed to reducing the problems of leveling a 
work piece, setting it at an angle and making an angular cut in it by 
providing an attachment to a folding ruler, which attachment has a level 
and angular ends against which the ruler may be folded to establish 
desired angular relationships. 
In an illustrative embodiment of the invention the attachment is formed as 
an elongated body or member with a longitudinal slot adapted to receive 
the ruler. A level is positioned on the member so that it and the section 
of ruler it holds can be leveled. One end of the body makes a 90.degree. 
angle with the axis of the slot and the other makes some smaller angle 
with respect to the axis of the slot. The folding ruler can be positioned 
in the slot so that one of its joints is adjacent an end of the body. By 
folding part of the ruler against the end, that part will be at an angle 
with respect to the part of the ruler in the slot. Therefore, the two 
parts of the ruler can be used to position a work piece or to cut an 
angular shape in it. This shape can be related to the horizontal or 
vertical direction because of the level. 
In preferred embodiments the slot is open and is provided with a spring 
device so that the attachment can be snapped onto a center portion of the 
ruler between its joints.

DESCRIPTION OF EXEMPLARY EMBODIMENTS 
In FIG. 1 there is shown an attachment 10 for a carpenter's ruler 12. The 
body 11 of the attachment is preferably elongated and made of a clear 
plastic material so that the ruler can be read through it. However, it can 
also be made in other shapes and of other materials. Also the use of a 
plastic reduces material and manufacturing costs, while still providing a 
rugged unit. A longitudinal slot 20 (FIG. 2B) is provided in the body for 
receiving the end section 15 of the folding ruler. The rest of the ruler 
after a first joint 19 is folded so that section 13 of the ruler is 
aligned within an end 16 of the body that is at an angle of less than 
90.degree. with respect to the axis of the slot 20. As a result sections 
13 and 15 of the ruler form the angle .alpha.. Preferably, this angle is 
either 45.degree. or 60.degree. since these angles have the most common 
use in construction. With the angle established between the sections of 
the ruler, it can be placed on a work piece so that the angle can be 
scribed in it; then a carpenter can cut the angle in the work piece. 
The other end 18 of the body is at a 90.degree. angle with respect to the 
axis of the slot. Therefore, the end section 15 of the ruler can be 
inserted into the body from that end so that sections 13 and 15 would form 
a 90.degree. angle. In order to make sure that the angles formed by 
folding the ruler against the ends of the body are accurate, the ends are 
made flat, at least where the ruler sections contact the ends. 
A horizontal level vial or bubble 14 and a vertical level 14' are also 
provided on the member or body 11. As a result the ruler 12 can be used to 
level widely separated work pieces with respect to each other, provided, 
of course, that the unfolded ruler is relatively straight. The levels also 
allow a work piece to be positioned in a vertical, horizontal or angular 
direction and permit an angle to be established on a work piece with 
respect to these directions. 
The attachment illustrated in FIG. 2A has a 45.degree. angle at end 16 and 
the 90.degree. angle at end 18. It is provided with one large horizontal 
level 14. As can be seen from FIG. 2B a recess 24 is established to one 
side of slot 20 to assist in inserting the level. Also one side wall of 
the slot is partially removed creating an aperture defined by the opposite 
ridges 26 and 26'. The size of the apertures and the recess 24 are such 
that during manufacture of the attachment, the level can be passed axial 
along slot 20 until it reaches a cut out in body 11 designed to hold it. A 
recess 22 is formed in the bottom of body 11 so that it may be moved along 
sharp-edged work pieces with ease or mounted on top of a center section of 
the ruler. The side 28 of the body opposite the aperture may be curved to 
magnify the markings on the ruler when read through the plastic body. 
The slot 20 is dimensioned so that the section 15 of the ruler fits snugly 
within it. However, since the ruler has a double thickness at joint 19, it 
is not possible to position the attachment of FIG. 2 on one of the middle 
sections of the folding ruler. In order to ocercome this disadvantage a 
two part attachment as shown in FIGS. 3A and 3B can be used. The main part 
30 of the body 11 holds the level 14 and creates the top and side walls of 
slot 20. The secondary part 32 of the body 11 has a C or L shape with one 
leg received within a groove in the main body. The part 32 forms the 
bottom edge of the slot 20. In order to hold these pieces (30 and 32) 
together, springs 34 are provided in holds leading from the recess in the 
main body to the upper surface of the main body. These springs 34 are 
attached to both parts of the body. Since the parts of the body are held 
together by spring force, the attachment can be added to a middle section 
of a folding ruler by pulling them apart a sufficient distance to allow 
the edges of the ruler to clear the opposite ridges 26, 26' of the body. 
Then when the parts are released the ruler section becomes trapped in slot 
20 by the ridges 26, 26'. 
As an alternative to the attachment shown in FIG. 3, a one-piece device 
that can be connected to a center section of the ruler as shown in FIGS. 
4A and 4B. In the device of FIG. 4 the bottom wall of the slot 20 is 
provided with a band 42 of spring steel or similar material. This band has 
a bend 43 in it which partially closes the open side of slot 20, thus 
serving the same function as ridge 26'. If a center section of the ruler 
has one edge inserted into the slot 20 under the ridge 26, the other edge 
can be pushed against band 42. This will cause band 42 to flatten, thus 
allowing the ruller to enter the slot. Once the ruler has proceeded into 
the slot past the bend in band 42, the band will spring up behind the 
ruler and hold it in the slot. 
The bottom of the attachment in FIG. 4 has a V-shape so that it may 
conveniently be placed on pipes or other cylindrical objects. This shape 
may also be used to fit the device on the edge of rectangular work pieces 
or work pieces with other shapes. The bottom has magnets 40 spaced along 
it so that the device can be held on metallic work pieces. The magnets can 
be replaced with a magnetic tape running along the bottom of the body. 
While the present invention has been particularly shown and described with 
reference to preferred embodiments thereof, it will be understood by those 
skilled in the art that various changes in form and details may be made 
therein without departing from the spirit and scope of the invention.