The invention is a tool for measuring the distance and angle between two points on two surfaces to measure position of the points and surfaces relative to one another to provide the user with angle and distance measurements which fully define the relationship between the surfaces and points without additional calculations.

A device is provided for use with a reference tool during the construction of metal structures. The device comprises a body having a groove formed therein for receiving a portion of a straight side of the reference tool. The body further comprises a base surface for co-operating with the surface of a metal workpiece. The base surface is configured whereby, when a portion of the straight side is received within the groove, the base surface is parallel to the straight side of the reference tool. A retention assembly is mounted on the body for retaining the portion of the straight side of the reference tool, when provided, within the groove. At least one magnet is mounted on the base surface for temporarily holding the device to the metal workpiece, thereby holding the reference tool in position.

An angle indicating instrument which, used in conjunction with a sliding T-Bevel, can indicate to users what miter saw setting to use when cutting two pieces of material for a miter joint, or for cutting one piece of material requiring a miter cut.

A combination square for usage with a grooved blade, comprising: a straight component having a first straight edge and a second straight edge perpendicular to the first straight edge; an angled component having a third straight edge and an angled edge; a marked scale comprising degrees; a marker, wherein the square is configured to allow indication by the marker of angles on the scale; a slot configured to allow accommodating the blade; and a locking screw configured to allow clamping the combination square onto the blade at a desired position along the blade; wherein the angled component is rotatably connected to the straight component; and the square is further configured to allow measuring a center of a circle coupled to the second straight edge and the angled edge at a second end of range of motion of the rotation by the straight component relative to the angled component.

The present disclosure provides a device for detecting a rotation angle of a prism and a method for using the same. The device for detecting a rotation angle of a prism is configured to detect, in the case that a prism film plate of a backlight module rotates relative to a display panel until the display panel displays a predetermined image, a rotation angle of the prism film plate relative to the display panel. The device for detecting a rotation angle of a prism includes: a stationary protractor; a film plate clamping mechanism configured to clamp the prism film plate; and a rotation mechanism which rotates the film plate clamping mechanism around an axis of the protractor. When the rotation mechanism drives the film plate clamping mechanism to rotate and the film plate clamping mechanism drives the prism film plate to rotate until the display panel displays the predetermined image, the rotation angle is detected based on an angle by which the film plate clamping mechanism rotates relative to the protractor.

A framing T-square protractor apparatus includes a first rule element having first and second edges, a surface, and a length of about 3 ft between the first and second edges; a second rule element having first and second edges, a surface, and a length of about 5 ft between the first and second edges, the second rule element being pivotally connected to the first rule element midway between the first and second edges of the first rule element; and a semi-circular element extending between the first and second edges of the first rule element to form an 180 degrees arc with 0 to 90 degrees angle indicia on each half, the semi-circular element being connected to the first and second edges of the first rule element and being adapted to movably receive the second rule element for sliding along the semi-circular element.

According to some embodiments, system comprises a metrological device operative to collect and transmit measurement data; and a hands-free communication device operative to receive the collected data and communicate the data to a user. Numerous other aspects are provided.

A protractor comprising an angle scale provided with a dial gauge with a circle center, one end of the bottom edge being connected with a first side edge, and the first side edge and the bottom edge forming an included angle, and the angle of the included angle being 135 degrees; a right angle rocker arm, comprising a reading arm part and a tail arm part forming a right angle with the reading arm part, the right angle rocker arm rotating relative to the angel scale such that a first edge of the tail arm part and the bottom edge form a first change included angle, the value of the first change included angle being read by means of the reading arm part and the dial gauge; and a locking structure for rotationally connecting the angle scale and the right angle rocker arm.

An instrument for establishing orientation of a pelvic prosthesis comprises a tripod having an angularly adjustable guide rod on it. The tips of the legs define a plane, and the guide rod is set by the surgeon to a defined orientation with respect to this plane on the basis of preoperative studies. In use, two of the legs of the instrument are positioned by the surgeon at defined anatomical locations on the pelvis (e.g., a point in the region of the posterior/inferior acetabulum and a point on the anterior superior iliac spine). The third leg then lands on the pelvis at a point determined by the position of the first two points, as well as by the separations between the third leg and the other two legs. The position of the guide rod then defines with respect to the actual pelvis the direction for insertion of a prosthesis.

The problem when fabricating structures from pieces requiring bent and straight sections is controlling the straight lengths, bend angles, and rotation between each bend. The very nature of assembling sections of tube into structures introduces a 3-dimensional aspect that needs to be controlled. Applications vary wherein the desired final structure of tubing containing bends needs be coplanar; other times, not. To date there is no device that measures bends, indicating accurate and precise degrees of angle while determining the centerline length of bent section simultaneously, and, planes tangent to the outer circumference of any of the tubes creating the structure. What's more, a device that indicates rotational lines along the straight sections of tube to be fitted with pre-bent sections. Additionally, the device allows for precise bending and fitting measurements to be transcribed onto tube to be bent and cut as per the device's function.