Abstract: A sight reticle for an archery bow sighting device is disclosed which has a plurality of permanently affixed aiming points spaced at calibrated intervals corresponding to target distances differing by a constant distance. The sight reticle includes a first portion consisting of an attachment screw (1) that attaches at one end to common existing archery bow sighting devices, a second portion (3) attached to the first at the other end of the screw which holds an aiming point carrier (7), and a third portion (7) connected to the second portion that carries multiple aiming points. The topmost aiming point (9) is coaxial with the attachment screw and all aiming points lie on a straight line substantially perpendicular to the long axis of the attachment screw. Rotating the attachment screw about its axis enables the archer to proportionally vary the perceived aiming point intervals in order to adjust the reticle to accommodate any arrow speed.

Abstract: Drawing apparatus for the preparation of technical drawings has a support for a drawing board on which paper may be attached. The support defines a frame surrounding the board which frame includes an upstanding lip for engagement by drawing instruments. Front, rear and side walls depend downwardly from the frame, and flare outwardly somewhat so that a series of apparatuses may be stacked for storage, with one nested partially within another. The lower edge of each side wall defines shoulders arranged so that the drawing surface may be disposed at one of three different angles to the horizontal when placed on a support surface, with that surface engaging different parts of the side walls. The frame may include an open-topped recess for holding drawing instruments, which recess will be closed by the next apparatus up, in a stack of such apparatus.

Abstract: A combined vernier gauge and protractor includes a primary rule having thereon a regular scale, a secondary piece slidable on the primary rule, and a protractor having a straight side pivotally mounted on and alongside the secondary piece. Such a device is provided in order that it can both provide the functions of a vernier gauge and a protractor. The secondary piece includes a vernier scale capable of cooperating with the regular scale to enable the present device to have a more accurate measurement.

Abstract: An image projection apparatus in which an image object plane contains a plurality of reflecting images and a light source and optical system projects a beam on each of said plurality of images. Spaced projection lenses are positioned to receive the light reflected from the images and direct the light on a projection surface with the plurality of reflected images in coregistration.

Abstract: An alignment tool for preparing through holes in a door to enable mounting a lock assembly includes a slidable bracket for securely positioning the tool in the mortise at the edge of the door. An angle element is connected to the bracket and to a support plate, which is perpendicularly disposed relative to the bracket. The support plate is formed with precisely positioned guide holes that indicates to the door installer exactly where the through holes are to be made.

Abstract: In a preferred embodiment, a carpenter's square with upright and laterally extending flat-bottomed straight edge members having a tape measure and its alternately extendable and retractable tape thereof having a bottom flat face, with the tape measure positioned and mounted on the upright and lateral extending members with its bottom flat face extending in the same plane or parallel to the plane as the flat bottoms of both the upright and laterally extending flat-bottomed members, with a window formed in a channeling structure through which any of the indicia on the tape may be viewed and aligned with a marker associated with the window which marker when aligned with an indicia indicates linear distance between the tapes extended end and the straight edge of the upright extending flat-bottomed straight edge member, there being a downwardly-extending flange extending from and mounted on the straight edge of the laterally extending straight edge member, and there being a leveling structure and mechanism thereon

Abstract: The need for engine maintenance is determined from valve stem wear by placing a cavity-containing housing of predetermined height on the cylinder head so that an exhaust valve stem on the cylinder head extends through the open bottom end of the housing into its cavity. A height measuring device, such as a depth micrometer, is supported on the top end of the housing and extends into the cavity of the housing until it contacts the top of the exhaust valve stem. At this point, the reading on the height measuring device indicates the distance between the top of the exhaust valve stem and the top of the housing. By subtracting this distance from the known height of the housing, the height of the exhaust valve stem can be calculated. By comparing the height of the exhaust valve stem when the engine is new to its height as periodically measured after the engine has been used, the increased height or "tulip condition" of the valves can be diagnosed, indicating the need for engine maintenance.

Abstract: The invention relates to a roll tape measure comprising an extractable measuring tape. Attached to the free end of the measuring tape (1) is a stop hook (4) which comprises a stop member (5) which projects approximately at right angles with respect to the measuring tape (1). That surface (6) of the stop member (5) which faces the measuring tape (1) is coated with friction bodies (7). These consist, for example, of sapphire crystals having a grain size of approximately 0,12 mm. This coating with friction bodies (7) provides the stop hook (4) with a good grip on the edge of the objects to be measured and with a high degree of resistance to wear.

Abstract: A drafting apparatus comprising a drawing board having at least two opposite, parallel sides, and arcuate guide means, detachably coupled to the at least two opposite, parallel sides, for guiding a straight edge along a radial path during formation of radiating perspective lines.

Abstract: A surveying rod leveling device and method for checking the accuracy of the level attached to the surveying rod comprising an elongated vertical bracket mounted to a vertical surface, having a movable joint at the top of the bracket and an adjustable horizontal plate with a center point at the bottom of the bracket. A plumb line and bob hangs from the movable joint. The center point of the adjustable bottom plate is aligned with the point of the plumb bob and the bottom plate is secured in place. The center point is removed from an aperture is the adjustable horizontal plate and the surveying rod is inserted into the same aperture. The upper end of the rod is secured to the joint at the top plate. The rod is thus held plumb and the level attached to the rod may be adjusted to produce an accurate reading.

Abstract: An automatic plumb, level and pointing tool uses a visible laser diode to project a beam in any of three different modes through a beam exit window. The tool, approximately the size and shape of a tape measure, can be placed on one edge to project a tilt-compensated vertical beam. Placed on another edge 90.degree.-rotated, the tool projects through the same exit window a tilt-compensated horizontal beam. When laid on either of its larger flat sides, the tilt compensation becomes inoperative and the tool projects a beam which is fixed relative to the housing. In a preferred embodiment, separate pendulous or cantilevered mirrors are used for vertical and horizontal tilt correction and are selected by the influence of gravity as the tool is laid on one edge or the other. In further described embodiments, two separate laser diodes may be used, or the laser tool may be intergrated with other tools such as a tape measure or a squaring tool.

Abstract: Apparatus and an associated method for determining the deviation of the distance between two points on a first object and the distance between two points on a second object. The apparatus and associated method are useful when measuring dimensions of short turn bores and O-ring grooves.

Abstract: A level vail includes a pair of elongated tubes, each having a top open end and a bottom open end. A pipe has two ends, respectively connected to the bottom ends of the elongated tubes. Water is contained in each of the elongated tubes, in each of which a floating article is also provided. A communicating member is provided on the top open end of each of the elongated tubes. One communicating member has at least one passage which communicate the interior of the elongated tube and the external atmsophere. A blocking member is movably disposed in the communicating member so that the passage of the communicating member can be opened and closed selectively.

Abstract: The sensor is of the type having a cylindrical body within which a measurement rod equipped with an outer measurement feeler bears a ferrite core which by its displacements influences the impedance of a system of coils to produce an electrical measurement signal. In the body, a fixed stop and an interposed movable stop make it possible to adjust the positioning of the measurement feeler in one or the other of two positions with respect to the electrical zero of the feeler and they have for this purpose interpenetration means with two stages spaced at an angle from each other and selected by manual push and rotation of the rod driving the movable stop in opposition to a spring and then release, in the manner of the so called "bayonet" connections.

Abstract: A tool is provided for use in mounting electrical boxes to wall studs. An upright member includes a plurality of slots along its length for receiving an electrical box. The slot has a width dimension to hold the box at a predetermined depth for mounting on a stud. The position of the slot along the length of the upright determines the height at which a box will be mounted. Different slots are provided for various box mounting height and depth requirements.

Abstract: Provided by the present invention, is an apparatus for and a method of ensuring an accurate parallel alignment between working surfaces of various rolls or cylinders disposed in a print station of a package printing arrangement. Further, this invnetion provides a method of and an apparatus for establishing substantial synchronization of the rotational speed of the working surface of a printing plate cylinder with the linear speed of a substrate material to be printed in a package printing arrangement. Additionally, this invention teaches an apparatus for and a method of providing documentation of certain preselected screen values and a percent of an image maintained by a particular printing arrangement.

Abstract: A vertically-movable carriage 18 has an attached first electric motor 22 which, through rollers 24, provides a friction drive with a traction bar 16. The carriage 18 is connected by a wire rope 26 to a counterbalance weight 32. The weight (32) has an attached second electric motor 36 which, through rollers 38, provides a second friction drive with a guide bar 34. The total mass of the motor arrangement is thereby split, with one motor compensating for the other.

Abstract: A device for measuring end play between a vehicle spindle and a wheel hub. A rotary thrust rod has a swivel connection with a housing threaded onto the spindle, such that the rod applies a pushing or pulling force to the spindle, depending on the direction of thrust rod rotation.

Abstract: A gunsight for a weapon including a channel sight with a sight post located on one end of the channel with one embodiment of the gunsight having a sight post with an opening for receiving an insert that has a contrasting color from the target the user intends to shoot at.

Abstract: A multipoint measuring system with measuring mechanism for fast exchanging of chucking appliance and automatic material withdrawal, comprises several slide guides arranged respectively at two side plates to use the three dimensional space to build several sets of measuring components so as to meet the requirement of measuring dimensions synchronously; the measuring implement for fast changing of chucking device and easy operation has a micro adjustment set which is provided at the end of a measuring base, and the said micro adjustment set can make further suitable adjustment to the position of measuring base by means of turning the bolt rod which is arranged on the measuring probe unit, so that it will be more easy, convenient and accurate during resetting operation; an automatic material withdrawal device consists of one set of rocket arm pin and the objects to be measured can be withdrawn to the measuring position by means of the oscillation motion of the said rocker arm pin.