Geometrical instruments – Distance measuring – By flexible tape
Patent
1988-03-08
1991-07-30
Haroian, Harry N.
Geometrical instruments
Distance measuring
By flexible tape
33775, 33763, 33773, 33780, G01B 310, G01B 312
Patent
active
050350641
DESCRIPTION:
BRIEF SUMMARY
This invention relates to linear measuring devices as used for example for measuring dimensions of rooms, buildings, or other objects, or for measuring the distance travelled along a surface. The term `linear` is intended also to include measurement of distances along non-straight paths or over non-flat surfaces.
So-called "tape measures" are well-known, consisting of a length of tape along which are marked the units of measurement, (e.g. centimeters or inches), the tape being wound on a rotary reel provided with rewind facilities. Such tape measures have certain limitations, for example only a limited length of tape can be stored on a reel, the tape cannot easily be read in the dark, or by the blind, and it may become dirty or be damaged.
Wheel measuring devices have also been proposed in which the wheel is run along the surface to be measured and the motion of the wheel operates a counter or display which represents units of measurement. These wheel measuring devices, are only applicable to certain specific uses and are subject to certain operating difficulties.
It is an object of the invention accordingly to provide an improved measuring device which will overcome some of the problems experienced with existing instruments.
Broadly stated the invention consists in a linear measuring device comprising a holder, a movable measuring element, a sensor for detecting movements of the measuring element, an electrical pulse generator coupled to the sensor, and electronic digital counter or calculator circuit connected to the pulse generator, and an output circuit connected to a visible or audible or recording output unit.
According to a preferred feature of the invention the sensing means includes a pulse generator sensitive to the movements of the element, and an electronic counter or calculator circuit connected to the pulse generator. In some forms of the invention the sensing means includes a rotary element engaging the measuring element so as to be turned by linear movement thereof, and arranged to generate pulses accordingly. Also the measuring element is elongate and has physical, mechanical, magnetic or optical linear measuring points, and the sensing means includes a detector capable of sensing such measuring points.
According to another preferred feature of the invention the measuring element is movable in one direction for measuring purposes, and includes means for shifting the measuring element in the opposite direction into a starting position.
In some forms of the invention the measuring element may be a rigid extendable member, this being particularly useful for measuring small dimensions. In other forms of the invention the measuring element is a long thin flexible line, tape or the like, wound in a coil or drum. Conveniently, it may be in the form of a fine thread. This is the most economical form and permits the maximum length to be contained on a drum of given dimensions.
Preferably the device also includes a spring, or motor-driven or manual rewind mechanism for the coil or drum.
Alternatively or in addition to the measuring element referred to, it may be in the form of a direct rotary measuring device comprising a rotor with at least part of its periphery exposed. This allows the device to measure uneven or non-linear surfaces or dimensions and it may, for example, be used to measure the internal circumference of a drum.
For a number of purposes such as use by the blind it is of advantage that the device should include an audible signalling device to provide audible information on the movement of the measuring element. Furthermore, the device may also include means for converting the display from imperial to metric or other units.
It is also of advantage to include means for connection to an external remote signal generator
The device may also be incorporated with a height-measuring system operating on the "vertical sextant angle" principle. Thus the device may include a vertical angle measuring device and a calculator programmed to combine the tangent of the measured angle with the sensed l
REFERENCES:
patent: 2706336 (1955-04-01), Gruber
patent: 4164816 (1979-08-01), Bergkuist
patent: 4181960 (1980-01-01), Tateishi
patent: 4185390 (1980-01-01), Tateishi
patent: 4195348 (1980-03-01), Kakotani
patent: 4316081 (1982-02-01), Washizuka
patent: 4377850 (1983-03-01), Simpson
patent: 4437241 (1984-03-01), Lemelson
patent: 4551847 (1985-11-01), Caldwell
patent: 4575944 (1986-03-01), Lin
patent: 4765063 (1988-08-01), Sing
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