Provided is a length measuring device, which includes a first case including a bobbin axis at a center, a second case to which a circuit board is attached, a bobbin mounted on the bobbin axis and around which a tape is wound, a sensor for sensing an amount of rotation of the bobbin rotated by the tape being pull-out, and first and second anti-tilt members for preventing tilting of the bobbin during rotation of the bobbin.

The capacitance-grating type digital display measuring tape includes a shell, a tape box, a tape body and a capacitance-grating sensor. A rotatable central shaft is disposed in the shell in an axial direction thereof. The tape box is mounted at one side in the shell close to the back side in the shell by the central shaft. A mainspring configured to pre-tighten the tape box is disposed in the tape box. The tape body is wound and collected in a groove in the outer circumference of the tape box. The capacitance-grating sensor is located in a position close to the front side in the shell. A self-adjusting mechanism is disposed at a position, corresponding to the outlet, on the inner wall of the shell. The self-adjusting mechanism automatically adjusts the speed at which the tape body extends out of or retracts into the shell.

Provided is a length measuring device, which includes a first case including a bobbin axis at a center, a second case to which a circuit board is attached, a bobbin mounted on the bobbin axis and around which a tape is wound, a sensor for sensing an amount of rotation of the bobbin rotated by the tape being pull-out, and first and second anti-tilt members for preventing tilting of the bobbin during rotation of the bobbin.

A tool, such as a tape measure, including a spring-based retraction system is shown. The tape measure includes a fluid-based retraction speed controller. The speed controller may be formed from a rotor/stator arrangement. The rotor is coupled to the reel and the stator is coupled to the housing opposing the rotor. The rotor converts some rotational energy from tape reel into movement of a fluid (e.g., movement of air, movement of oil, etc. through friction) which acts to slow or limit the retraction/rotational speed of the reel as the retraction spring expands driving the reel during tape blade retraction.

A tool, such as a tape measure, including a spring-based retraction system is shown. The retraction system utilizes an epicyclic gear train coupled between the tape blade winding reel and a rotating arbor or axle within the tape measure. A spiral spring has an outer end coupled to the reel and an inner end coupled to the axle. The gear train may be a reduction gear train such that the axle rotates slower than the reel. By coupling the spiral spring between the gear train input and gear train output, high energy density springs may be used, which may allow for decrease in housing size, increase in tape length or thickness for a given housing size, and/or advantageous retraction speed control.

A tape measure including a housing arranged to enclose an internal cavity, where the housing defines a front wall. A port is formed in the housing and spaced a non-zero distance from the front wall. A measuring tape is at least partially disposed within the internal cavity of the housing and extends through the port. The measuring tape is rotatably coupled to the housing. A finger guard assembly is positioned adjacent the front wall, such that the finger guard assembly cooperates with the port to define a space therebetween. The measuring tape passes through the space outside of the housing to facilitate the control of the retraction and extension of the measuring tape through contact within the space.

A tape measure includes a housing with first and second housing portions; a reel configured to be secured between the first and second housing portions, the reel containing a tape blade wound thereon and partially extending therefrom terminating in a hook portion; and an integral component coupled to the first and second housing portions, including an aperture defining a finger brake, the finger brake exposing the tape blade for engagement by a user. The tape blade is biased to retract into the housing, winding around the reel, such that in a fully retracted position the hook portion abuts the portion of the mouth of the tape measure. In an extended position the tape blade is unwound from the reel such that the hook extends away from the integral component. An integral component including an aperture defining a tape measure mouth and a light emitter receiving slot is also disclosed.

A tape measure, a measuring device, and a measuring method are provided. The tape measure includes a first shell, a tape, an optical positioning assembly, and a first controller. The tape has one end mounted in the first shell and the other end extending out of the first shell and capable of moving in a first measuring direction relative to the first shell. An imaging sensor in the optical positioning assembly, when working, is capable of consecutively acquiring images of the tape in a moving process and then performing feature comparison on the images to determine a relative displacement of the tape moving in the first measuring direction in real time. Further, the controller of the tape measure is capable of determining, based on the relative displacement, a length by which the tape extends out of the first shell.

A tape measure, a measuring device, and a measuring method are provided. The tape measure includes a first shell, a tape, an optical positioning assembly, and a first controller. The tape has one end mounted in the first shell and the other end extending out of the first shell and capable of moving in a first measuring direction relative to the first shell. An imaging sensor in the optical positioning assembly, when working, is capable of consecutively acquiring images of the tape in a moving process and then performing feature comparison on the images to determine a relative displacement of the tape moving in the first measuring direction in real time. Further, the controller of the tape measure is capable of determining, based on the relative displacement, a length by which the tape extends out of the first shell.

A retractable rule assembly comprises a housing, a reel, an elongated blade, a hook, a coil spring, and a blade advancer. The reel is rotatably mounted in the housing. The elongated blade is wound on the reel and is constructed and arranged to extend outwardly through an opening in the housing. The hook is positioned on a distal end of the blade. The coil spring is configured to rotate the reel in the housing assembly in a direction to wind up the elongated blade when extending outwardly of the housing. The blade advancer is constructed and arranged to be manually engaged and moved relative to the housing and into contact with the blade and/or the reel. The blade advancer is movable against a bias of the coil spring to advance the blade in a direction that extends the blade outwardly from the housing.