US 5,459,932 A · Automatic level and plumb tool

Abstract

An automatic plumb, level and pointing tool uses a visible laser diode to project light beams in two modes through two windows. In the first mode of operation, the unit is able to project a plumb-up beam and a level beam of light while resting on a surface which is as much as five degrees out of level. In the second mode of operation the unit is able to project two orthogonal beams of light both approximately in the horizontal plane for aligning one or more reference lines. An accurate, low cost method of generating level and plumb beams and planes of light is disclosed. One method uses an approximately leveled platform combined with a weak optical correction. The approximate leveling is done using a single wire or coil spring pendulum element which allows the platform to level itself to within a small fraction of true level, and remaining correction is provided by a weak negative lens or a weak reverse telescope. In alternative embodiments, all leveling is accomplished using a very flexible coil spring as a pendulum element, or a chain link connection in combination with such a spring. Several accessories are disclosed for use with the laser tool.

Claims30

Dependent claims

A portable hand tool for projecting a laser beam in level or plumb direction, in spite of a tilted condition of the tool itself, to align the projected laser beam in two stages to substantially truly level or plumb orientation, comprising:

a housing,
laser means with projection means for projecting a primary laser beam,
pendulous mounting means secured to the housing and depending internally in the housing, including a platform, for effecting a first stage of alignment when the housing is not truly level or plumb, by tilting the platform angularly relative to the housing as induced by tilt of the housing, said laser means being mounted on the platform of the pendulous mounting means such that the projected primary beam from the laser means changes in angular relationship to the housing and is aligned to nearly level or plumb orientation when the housing is tilted, leaving a small angle of deviation of the primary laser beam from a truly level or plumb orientation, and
weak lens means secured to the housing and positioned in the path of the primary laser beam, in a second stage of alignment, having a position and optics selected for aligning the laser beam to substantially truly level or plumb orientation as a final laser beam, by bending the path of the primary laser beam by said small angle of deviation.

1 more element

A portable hand tool for projecting a level plane of laser light, in spite of a tilted condition of the tool itself to align the projected laser plane in two stages to substantially level orientation, comprising:

a housing,
laser means with projection means for projecting a primary laser beam,
pendulous mounting means secured to the housing and depending internally in the housing, including a platform, for providing a first stage of alignment when the housing is not truly level or plumb, by tilting the platform angularly relative to the housing as induced by tilt of the housing, said laser means being mounted on the platform of the pendulous mounting means such that the projected primary beam from the laser means changes in angular relationship to the housing and is mostly aligned to nearly plumb orientation when the housing is tilted, leaving a small angle of deviation of the primary laser beam from truly plumb orientation,
axicon reflector means fixed to the platform of the pendulous mounting means and in the path of the projected primary beam from the laser means, for producing generally a plane of laser light from the projected primary base, and
weak toroidal lens means secured to the housing and positioned in the path of the plane of laser light in a second stage of alignment, having optics selected for aligning the plane of laser light to substantially truly level orientation, by bending the path of the plane laser light by said small angle of deviation.

2 more elements

Dependencies are inferred from the claim text.

Automatic level and plumb tool

Life of this patent

Automatic level and plumb tool

Life of this patent

Abstract

Claims30