Geometrical instruments – Straight-line light ray type – Celestial
Reexamination Certificate
1999-10-14
2001-10-16
Gutierrez, Diego (Department: 2859)
Geometrical instruments
Straight-line light ray type
Celestial
C968S416000, C968S415000
Reexamination Certificate
active
06301793
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an equatorial sundial, and more particularly to a new and novel equatorial sundial with an adjustable base assembly that uses one or more concave cylindrical focusing mirrors to form a sharply demarcated beam of light either upon opaque or multi-faced translucent surfaces, to accurately tell time in a variety of geometric and aesthetic configurations.
2. Description of the Prior Art
Equatorial sundials have been known in the prior art for centuries. Most types of equatorial sundials cast a shadow from a gnomon forming a line upon a surface where the time is then read. The prior art also includes equatorial sundials which instead reflect or project unfocused light to indicate the time. These have included a masked reflecting mirror to cast a darkened line from the masking upon the dial as in U.S. Pat. No. 3,786,570 Davies; a reflected spot of light projected upon a translucent elliptical surface as in U.S. Pat. No. 5,197,199 Shrader; and a sunbeam that enters a hole in the top of a translucent sphere which casts a spot on the inside of the sphere allowing time to be read on the external surface of the device as in U.S. Pat. No. 89,585 Johnson. The limitations known in the prior art utilizing shadows is that they inherently form indistinct demarcations of time because of the penumbra the shadow creates and therefore these types of sundials are not able to give sharply defined demarcations for telling of time in a more precise manner.
The limitations known in the prior art with reflected un-focused light is that the width of the resultant image is blurred because it equals the width of the sun's image plus the width of the mirror. Each of the aforementioned sundials require a broad field or screen for the time to be displayed since each relies upon one light directing or shadow directing component of the device to function throughout the sun's total traverse across the horizon. This breadth of field or screen and lack of a sharply focused demarcation from the sun makes the reading of time from the sundial more difficult and in some instances requiring a modicum of study to discern the time.
A further limitation in the prior art is the difficulty in setting up and properly aligning the sundial accurately in accordance with the latitude where the sundial is located. The present invention utilizes an adjustable base assembly that permits a user to set up the sundial with exceptional accuracy.
Given the limitations of the prior art there is an apparent need for an equatorial sundial with an adjustable base assembly that utilizes a reflective means whereby the time indicator will be sharply focused and the visual field or screen of the time indicator may be narrowed, thereby making the dial easier to be read. The prior art's single component shadowing or reflecting time indicator source also limits the geometric and aesthetic configurations of sundials utilizing these designs. In this respect, the present invention disclosed herein substantially fulfills these needs.
SUMMARY OF THE INVENTION
In view of the foregoing limitations inherent in the known types of equatorial sundials present in the prior art, the present invention provides an apparatus that has been designed with an adjustable base assembly for easy and accurate installation which is able to indicate time by focusing the sun's light with one or more concave cylinrical focusing mirrors providing a sharply focused demarcated line capable of utilizing a narrow, easier read, dial or screen of various geometric and aesthetic configurations, which are improvements which are patently distinct over similar devices which may already be patented or commercially available. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new, novel and useful equatorial sundial with an adjustable base assembly that uses one or more concave cylindrical focusing mirrors to form a sharply demarcated beam of light either upon opaque or multi-faced translucent surfaces, to accurately tell time in a variety of geometric and aesthetic configurations. There are many additional novel features directed to solving problems not addressed in the prior art.
To attain this, the present invention generally comprises one or more cylindrical focusing mirrors which indicate the time by projecting a bright, sharply demarcated line whose width is determined solely by the angular width of the sun in the sky, and is not significantly broadened or degraded by increasing the width (aperture) of the mirror. A wider aperture (mirror width) would serve to increase the brightness, but not the width, of the focused line. This invention is an equatorial sundial with an adjustable base assembly which when configured with a plurality of concave cylindrical focusing mirrors measures units of time by projecting a sharply demarcated line of light onto a calibrated opaque or translucent surface indicating minutes past said unit of time which will repeat across this surface throughout the daylight hours in a number of units of time that is equal to the number of concave cylindrical focusing mirrors. For example because it takes one hour for the sun to move 15 degrees across the sky, movement of the reflected ray by 15 degrees will subtend a time of 1 hour as well and therefore an hour unit of time may be selected by utilizing one concave cylindrical focusing mirror for each hour. The adjustable base assembly is generally comprised of four rotatably attached components that permit a user to properly adjust the tilt of the sundial upon set-up accurately and easily according to the sundial's latitudinal location of use.
In the use of the present invention, the concave cylindrical focusing mirrors may be placed in a variety of differing positions and utilizing differing numbers of said concave cylindrical focusing mirrors in accordance with the desired field or screen for the reading of the time, which visual field or screen may also appear in a variety of geometric and aesthetic configurations and may be opaque or translucent to facilitate multi-surface reading of time.
The present invention is designed to overcome the present limitations inherent in equatorial sundials, namely imprecise installation and set-up, poorly focused time indicators and difficult to read visual field or screens for the telling of the time.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention, method and apparatus, is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention, method and apparatus, is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting in any way the scope of this invention or claims made herein.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions and methods insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Off
Gottesman William
Manock Jerrold C.
Weiss Karsten H.
Benson Eric R.
Gutierrez Diego
Smith R A
LandOfFree
Equatorial sundial apparatus utilizing one or more concave... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Equatorial sundial apparatus utilizing one or more concave..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Equatorial sundial apparatus utilizing one or more concave... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2550770