A bumper spring assembly having a one piece mandrel including an integral head piece is further configured with a cage assembly retained on the mandrel with a cage nut locked to the mandrel to obviate the need for pins, set screws, and the like, to provide a more robust assembly. In two embodiments the cage nut is locked to the mandrel in a swaging operation. Improved flow of fluids through and around the bumper spring assembly are also provided.

Apparatuses and methods of operating a linear differential (100, 600) are described herein. The linear differential (100, 600) contains a slide portion (102) with parallel right-hand and left-hand threaded rods (112, 114). Threaded onto the right-hand and left-hand threaded rods (112, 114) and attached to the slide portion (102) are right-hand and left-hand gears (116, 118). Meshed between the right-hand and left-hand gears (116, 118) and also attached to the slide portion (102) is a driven gear (200). An end effector (104) is attached to the driven gear (200) and is configured to translate along a translation axis (110) and rotate around a rotation axis (120).

The drilling machine includes a spindle, a spindle motor, a frame including, a linear motion guide support plate, a motor support portion, and a ram support plate disposed at a front end of the linear motion guide support plate, and having a height lower than the motor support portion, a linear motion guide disposed on the reference surface, a slider having a nut mounting hole to reciprocate along the linear motion guide, and having a height substantially the same as the motor support portion, a ram penetrating the first ram guide hole, a feed screw including a screw shaft having a rear end supported by the motor support portion and a front end that is a free end, and a nut fastened to the nut mounting hole; and a feed motor connected to the screw shaft.

An elongated tool holder has a tool anti-vibration component constituting a mass housing portion provided with an enclosed interior cavity, and an anti-vibration arrangement occupying the enclosed interior cavity. The anti-vibration arrangement includes two vibration absorbing masses disposed within the holder cavity and elastically suspended therein by at least three resilient suspension members contacting an inwardly facing cavity wall surface. The two vibration absorbing masses are made from different materials and have different lengths. A cutting tool is provided with the tool holder.

A bumper spring assembly having a one piece mandrel including an integral head piece is further configured with a cage assembly retained on the mandrel with a cage nut locked to the mandrel to obviate the need for pins, set screws, and the like, to provide a more robust assembly. In two embodiments the cage nut is locked to the mandrel in a swaging operation. Improved flow of fluids through and around the bumper spring assembly are also provided.

A system includes a power tool and a suction device that is connected to the power tool via a suction hose. The power tool is drivable into a wall or into a substrate by a negative pressure produced by the suction device. A method includes driving the power tool into the wall or into the substrate by using the negative pressure produced by the suction device that is connected to the power tool via the suction hose.

A coring unit comprises a clamping arrangement for releasably attaching the coring unit to a structure into which a core is to be cut. A bit is provided comprising an elongated tubular body having a cutting surface at a first circular end of the elongated tubular body for cutting the core. The unit includes a drive system adapted to rotate and linearly translate the bit so that the drive system rotates the bit and moves the bit with respect to the clamping arrangement to advance and retreat the bit through the structure to cut the core from the structure. A method of using the coring unit is also described. The unit and method permit an accurate, reliable, safe, and reproducible cutting of a hole in a structure. The unit and method find particular application in cutting holes in studs of wood frame structures to accommodate services such as wires and piping.

A bumper spring assembly having a one piece mandrel including an integral head piece is further configured with a cage assembly retained on the mandrel with a cage nut locked to the mandrel to obviate the need for pins, set screws, and the like, to provide a more robust assembly. In two embodiments the cage nut is locked to the mandrel in a swaging operation. Improved flow of fluids through and around the bumper spring assembly are also provided

A magnetic base for an electric machine tool, in particular for a magnetic core drilling machine, having a body in which is accommodated at least one first permanent magnet, the magnetic force of which combines with the magnetic force of at least one second permanent magnet to form a resultant holding force, wherein the at least one second permanent magnet is supported in the body such that it can rotate about a rotation axis through an angle of rotation between a first position in which the resultant holding force of the magnetic base is maximized and a second position in which the resultant holding force of the magnetic base is minimized, and having a controller for rotating the second permanent magnet between the first position and the second position.

A work machine unit includes: a support member assembled to an end effector connection part of an operating machine; a work machine part assembled to one end of the support member; and a linear guide disposed at another end of the support member across its connection to the end effector connection part from the support member, arranged in parallel to an axial direction of the work machine part, and configured to abut against a work object or its peripheral structural object. Further, the linear guide is passed through a through-hole formed in the support member, and the support member is configured to move in the axial direction of the work machine part as guided by the linear guide.