A system for servicing a water well including a well pipe having a pump and a motor at a bottom thereof. The well head has a platform to support a winch thereon. Also supported on the platform is an upstanding mast having a return wheel at a top thereof. One end of a cable is attached to the winch and another end is attached to a top of the well pipe after having been trained over the return wheel at the top of the mast. Activating the motor on the winch will pull the well pipe from the deep wel...

A collimating lens includes a first end face with an LED accommodation hole for accommodating an LED lamp, a second end face, which is disposed opposite to the first end face and has an area greater than the first end face, and a sidewall, which is connected between the first end face and the second end face and has a first wall section and a second wall section. The second wall section extends from the second end face toward the first end face to a predetermined distance. The first wall section...

An illumination system comprising, a) a light source; b) a light-directing assembly (1) in close proximity to the light source and comprising a plurality of microprisms (6), each microprism comprising an input surface (7) that admits light radiating from the light source, an output surface (8) distal from and parallel to the input surface (7), and at least one sidewall (9) disposed between and contiguous with the input and output surfaces and forming an obtuse tilt angle with respect to the inpu...

In a lighting apparatus which illuminates light ray from an illumination light source through a light distribution lens onto an illuminated surface, an inner surface of the light distribution lens is formed as continuous surface to receive incident ray in the perpendicular direction, and an outer surface of the lens for refracting outgoing ray is formed based on the equations which are made in consideration of the illuminance on the illuminated surface, thereby uniform illuminance is obtained on...

Light-transparent lens structures typically formed of conventional synthetic acrylic resins and intended for use as lenses in a lensed fluorescent troffer or similar lighting fixture, the lens structures of the invention are characterized by repeating patterns of conical or pyramidal depressions formed in the lens with upper portions or apices thereof being inverted. The lens structures of the invention preserve the angular relationships of lens material to air interfaces of conventional conical...

A flashlight and holder cooperate to automatically turn the flashlight on when the flashlight is removed from the holder and turn the flashlight off when the flashlight is returned to the holder. The flashlight includes a bottom cap with a magnetically actuated switch. The holder includes a magnet which cooperates with the switch to turn off the flashlight. The magnet also provides some degree of attraction for retaining the flashlight in the holder. The holder may be a stationary holder for hol...

A vehicle headlamp has a reflector provided with a reflective area lying on a surface defined by rotating an ellipse about an axis which passes through the inner focus of the ellipse and which is inclined an acute angle (1.degree.-2.degree.) to the focal axis of the ellipse. A shielded filament for producing an inclined cut-off line to the beam is used and is orientated in the opposite sense to that in which it is orientated in a conventional headlamp for producing an inclined cut-off. To produc...

An electronic learning aid automatically develops and displays problems, and functions to compare an answer introduced by a student with a correct answer stored in the electronic learning aid. A time counter is provided for counting a time period required by the student for conducting the exercise. A manual stop switch is provided for terminating the automatic development of the problems and the counting operation of the time counter. Upon actuation of the manual stop switch, the time period sto...

An electronic learning aid includes a circuit for automatically developing problems, a display for displaying the problems, an input for introducing a calculated answer, and a determination circuit for detecting whether the introduced answer is correct. The display includes a first display unit of plural digits for displaying the problems, and a second display unit of plural digits for displaying the problem number, the score, the correct answer number, and the exercise number.

A light source that prevents broken pieces from dispersing to the outside without increasing the number of components while efficiently cooling a light-emitting tube is provided. The light source (10) has: a light-emitting tube (11) having a light-emitting portion (111) where light beam is emitted by electric discharge between electrodes and a sealing portion (112) provided on both sides of the light-emitting portion (111); a reflector (12) that reflects the light beam emitted by the light-emitt...