Line angle degree level instrument

Claim 2

A line angle degree level instrument comprising: a protractor body section formed with horizontally spaced vertically disposed parallel walls with the upper edges thereof lying in a single transverse plane, said vertical walls being connected along the upper extremities of their vertical edges by spaced transverse wall sections, at least one of said vertical walls being transparent and provided with a protractor scale having degree graduations with the centerline of said scale being perpendicular to said transverse plane; a pendulum indicator arm pivotally mounted for free movement between said vertical walls on an axis which is parallel with said transverse plane at a point corresponding to the center of said protractor scale; a centrally disposed indicator line on said indicator arm a portion of which is disposed opposite said protractor scale; support means engaging said protractor body section extending longitudinally parallel to said transverse plane and spaced above said pendulum indicator arm to freely support said body section, said support means being in transverse supporting engagement adjacent its ends with said body section and having clearance longitudinally for longitudinal expansion under tension of said support means relative to said body section, and means connecting the spaced lateral walls adjacent said upper edges to form a protective enclosure for the pivotally mounted pendulum indicator arm.

Claim 3

A line angle degree level instrument as in claim 1, wherein said support means is a tension-transmitting means and has fastening means at the opposite ends thereof for attaching thereto a flexible support line.

Claim 4

A line angle degree level instrument as in claim 1, wherein said support means and said body section are pivotally as well as axially movable relative to each other.

Claim 5

A line angle degree level instrument as in claim 1, wherein said support means is an elongated element extending through said transverse wall sections in journaled relationship.

Claim 6

A line angle degree level instrument as in claim 1, wherein said body section has slots formed in it extending inwardly at said transverse wall sections and a connecting slot in the adjacent one of said vertical walls and said support means is received laterally in said slots.

Claim 7

A line angle degree level instrument comprising: a protractor body section formed with horizontally spaced substantially parallel vertical walls with the upper edges thereof lying in a single transverse plane, said vertical walls being connected along their lower edges and lateral edges by a transverse wall section; at least one of said vertical walls being transparent and provided with a protractor scale having degree graduations with the centerline of said scale being perpendicular to said transverse plane; a pendulum arm pivotally mounted between said vertical walls on an axis which is perpendicular to said vertical walls and parallel with said transverse plane at a point corresponding to the center of said protractor scale, a centrally disposed indicator line on said pendulum arm a portion of which is disposed opposite said protractor scale; said protractor body section having an elongated support means extending longitudinally therethrough for pivotal support of said body and spaced above said pendulum arm with the ends thereof extending beyond opposite end portions of said body section; an upper wall section connecting the spaced vertical walls adjacent said upper edges to form a protective enclosure for said pendulum arm, and a frame means having a planar base section disposed parallel with the said transverse plane of the upper edges of the body section and including at the opposite ends of the base section upwardly extending arm sections which are adapted to pivotally support said protractor body section therebetween for relative pivotal movement about said support means; said body section being freely mounted on the support means with clearance for relative longitudinal expansion of said support means so that tension applied longitudinally to the support means is not applied to the body section.

Claim 8

A line angle degree level instrument comprising: a protractor body section formed with horizontally spaced substantially parallel vertical walls with the upper edges thereof lying in a single transverse plane, said vertical walls being connected along their lower edges and lateral edges by a transverse wall section; at least one of said vertical walls being transparent and provided with a protractor scale having degree graduations with the centerline of said scale being perpendicular to said transverse plane; a pendulum arm pivotally mounted between said vertical walls on an axis which is perpendicular to said vertical walls and parallel with said transverse plane at a point corresponding to the center of said protractor scale, a centrally disposed indicator line on said pendulum arm a portion of which is disposed opposite said protractor scale; said protractor body section having an elongated support means extending longitudinally therethrough for pivotal support of said body and spaced above said pendulum arm with the ends thereof extending beyond opposite end portions of said body section; an upper wall section connecting the spaced vertical walls adjacent said upper edges to form a protective enclosure for said pendulum arm, and a frame means having a planar base section disposed parallel with the said transverse plane of the upper edges of the body section and including at the opposite ends of the base section upwardly extending arm sections which are adapted to pivotally support said protractor body section therebetween for relative pivotal movement about said support means; said body section being freely mounted on the support means with clearance for relative longitudinal expansion of said support means so that tension applied longitudinally to the support means is not applied to the body section.

Claim 9

A line angle degree level instrument as in claim 6, wherein said upper edges of said body section extend above said arm sections to permit said upper edges being placed in direct contact with a surface without interference from said arm sections when making a measurement with said instrument.

Claim 10

A line angle degree level instrument as in claim 6, wherein said support means is detachably mounted in a transverse passage through each of said arm sections of said frame member with an access slot extending between each said transverse passage and surface portions of the respective arm sections.

Claim 11

A line angle degree level instrument as in claim 6, wherein said support means has eyelet means at the opposite end thereof for attaching thereto a flexible support line.

Claim 12

A line angle degree level instrument comprising: a protractor body section of plastic formed with spaced vertical walls with the upper edges thereof lying in a single transverse plane, said walls being connected along their lower edges and lateral edges by a transverse wall section, at least one of said walls being transparent and provided with a protractor scale having degree graduations with the centerline of said scale being perpendicular to said transverse plane; a vertically hanging pendulum arm pivotally mounted at its upper end between said lateral walls on an axis which is parallel with said transverse plane at a point corresponding to the center of said protractor scale and bodily widened at its lower end to provide a low center of gravity; a centrally disposed indicator line on said arm a portion of which is disposed horizontally between said protractor scale and said center of gravity, said protractor body section having a rigid support means extending longitudinally therethrough spaced above said pendulum arm and with the ends thereof extending with clearance for relative longitudinal expansion of said support means beyond the opposite ends of said body section to pivotally support the said body section in a depending position without longitudinal tension upon the support means being transmitted to said body section; said rigid support means having at the outer ends thereof means for attaching thereto a flexible support line adapted to vertically support said protractor body section; and an upper wall section connecting the spaced walls adjacent said upper edges to form a protective enclosure for the pivotally mounted pendulum arm.

Claim 13

A line angle degree level instrument comprising: a protractor body section of plastic formed with spaced vertical walls with the upper edges thereof lying in a single transverse plane, said walls being connected along their lower edges and lateral edges by a transverse wall section, at least one of said walls being transparent and provided with a protractor scale having degree graduations with the centerline of said scale being perpendicular to said transverse plane; a vertically hanging pendulum arm pivotally mounted at its upper end between said lateral walls on an axis which is parallel with said transverse plane at a point corresponding to the center of said protractor scale and bodily widened at its lower end to provide a low center of gravity; a centrally disposed indicator line on said arm a portion of which is disposed horizontally between said protractor scale and said center of gravity, said protractor body section having a rigid support means extending longitudinally therethrough spaced above said pendulum arm and with the ends thereof extending with clearance for relative longitudinal expansion of said support means beyond the opposite ends of said body section to pivotally support the said body section in a depending position without longitudinal tension upon the support means being transmitted to said body section; said rigid support means having at the outer ends thereof means for attaching thereto a flexible support line adapted to vertically support said protractor body section; and an upper wall section connecting the spaced walls adjacent said upper edges to form a protective enclosure for the pivotally mounted pendulum arm.