Abstract: A collar member is for a collar assembly of a cutting system and method. The cutting system has a spindle and a cutting tool coupled to the spindle. The collar assembly includes a number of components and a gas flow system having a number of gas flow delivery apparatus and a number of conduits. The collar member includes a support portion structured to be coupled to the spindle, and a chamber portion extending from the support portion and being structured to be coupled to each of the number of components, the number of gas flow delivery apparatus, and the number of conduits. The support portion has a side portion having an edge portion defining a thru hole in order to form a passageway from an interior of the support portion to an exterior thereof.

Abstract: Devices, systems, and methods are provided for controlling a quantity of cutting fluid dispensed for a cutting tool within a CNC or other machining system. The devices, systems, and methods may include controlling multiple fluids such that coolant, lubricant, or other fluids can be delivered at different locations, at different flow rates, have their flow rates changed independently, and/or have their flow rates changed dynamically during a machining operation. In some embodiments, a feedback loop or input may be provided to obtain and/or provide information regarding the machining operation—such as cutting force, cutting temperature, cutting friction, machining operation, tool in use, work piece geometry, and/or material—and automatically and/or independently modify the fluid flow rates. The fluid may be atomized with air or other gases to minimize the quantities of fluid used. Components in the system may be modular to allow the system to be used with existing and new machining technologies.

Abstract: Grinding is performed on an outer peripheral surface of a shaft member while rotationally driving the shaft member under a state in which both end surfaces of the shaft member are sandwiched between a pair of support portions. A convex surface is formed on one axial end surface of the shaft member or an end surface of one of the pair of support portions, and a flat surface is formed on the other of the one axial end surface of the shaft member and the end surface of the one of the pair of support portions. The flat surface and an apex of the convex surface are brought into contact with each other to support one axial end portion of the shaft member.

Abstract: A wafer edge trimming tool includes an abrasive tape and a holding module configured to hold the abrasive tape against portions of an edge of a rotating wafer during a wafer edge trimming process.

Abstract: A honing machine (100) for honing rotationally symmetrical bore holes in workpieces has a honing spindle (120), which is movably mounted in a spindle housing (130), is rotatable about a spindle axis (122) by means of a rotary drive (140), can be driven in an oscillating manner parallel to the spindle axis by means of a lifting drive (150) and has at a tool-side end means for securing a honing tool arrangement (200), which has a tool body (220) carrying at least one honing element, which by axial displacement of a tool-side expanding element (330) that is axially displaceable inside the tool body can be infed radially in relation to a tool axis (214) and can be pressed by a pressing force against an inner side of a bore hole to be machined.

Abstract: Polishing pads with foundation layers and polishing surface layers are described. In an example, a polishing pad for polishing a substrate includes a foundation layer. A polishing surface layer is bonded to the foundation layer. Methods of fabricating polishing pads with a polishing surface layer bonded to a foundation layer are also described.

Abstract: Polishing pads with grooved foundation layers and polishing surface layers are described. In an example, a polishing pad for polishing a substrate includes a foundation layer having a pattern of grooves disposed therein. A continuous polishing surface layer is attached to the pattern of grooves of the foundation layer. In another example, a polishing pad for polishing a substrate includes a foundation layer with a surface having a pattern of protrusions disposed thereon. Each protrusion has a top surface and sidewalls. A non-continuous polishing surface layer is attached to the foundation layer and includes discrete portions. Each discrete portion is attached to the top surface of a corresponding one of the protrusions of the foundation layer. Methods of fabricating polishing pads with a polishing surface layer bonded to a grooved foundation layer are also described.

Abstract: Automatic handling apparatus having a suction-head sucking and holding a workpiece, an arm is connected to and moves the suction-head, and a stage on which the workpiece to be carried to the carrier holding hole is mounted, the suction-head has a movable section which is movable within a parallel plane to the suction-head body, the movable section to suck and hold the workpiece, and has positioning pins stretched in vertically lower direction and, at loading time, the workpiece held by the movable section into the carrier holding hole, the positioning pins are appressed against tooth-bottoms of a gear on the carrier outer periphery and movable section moving within the parallel plane. The carrier is pushed against the sun gear side to fix the carrier position and direction, and the held workpiece is carried into the holding hole. Consequently, the automatic handling apparatus load the workpiece into the carrier holding hole.

Abstract: This invention relates to compressed composite backing materials (e.g., compressed polymer impregnated backing substrates) and coated abrasive articles that include such compressed composite backing materials. This invention also relates to methods of making and using said compressed composite backing materials and coated abrasive articles. The claimed processes and systems related to the use and manufacturing of coated abrasive articles are improved and cost effective.

Abstract: Thermally stable diamond constructions comprise a diamond body having a plurality of bonded diamond crystals, a plurality of interstitial regions disposed among the crystals, and a substrate attached to the body. The body includes a working surface and a side surface extending away from the working surface to the substrate. The body comprises a first region adjacent the side surface that is substantially free of a catalyst material and that extends a partial depth into the diamond body. The first region can further extend to at least a portion of the working surface and a partial depth therefrom into the diamond body. The diamond body can be formed from natural diamond grains and/or a mixture of natural and synthetic diamond grains. A surface of the diamond body is treated to provide the first region, and before treatment is finished to an approximate final dimension.

Abstract: A coated abrasive product includes green, unfired abrasive aggregates having a generally spheroidal or toroidal shape, the aggregates formed from a composition comprising abrasive grit particles and a nanoparticle binder, wherein the abrasive aggregates are dispersed within a polymer resin coating, and wherein the coated abrasive product is capable of superfinishing a metal surface having an initial Ra in the range of about 1.5 micro inches to about 12.5 micro inches prior to application of the coated abrasive product and after application the surface has an Ra of less than 1.0 micro inch.

Abstract: The present disclosure provides a carrier disk for holding at least one cutting, grinding or polishing element in a floor grinding machine. The carrier disk comprises a carrier body having a downwardly exposed face, at which the grinding element is arranged, a opening formed in the carrier body and a plurality of flanges extending axially from the carrier body and between the opening and a radially outer edge of the carrier body.

Abstract: A method of fabricating a diamond compact includes functionalizing surfaces of diamond nanoparticles with fluorine; combining the functionalized diamond nanoparticles with a non-group-VIII metal to form a particle mixture; and subjecting the particle mixture to high pressure and high temperature (HPHT) conditions to form inter-granular bonds between the diamond nanoparticles. A cutting element for an earth-boring tool includes a plurality of grains of diamond material; a plurality of diamond nanoparticles bonded to the plurality of grains of diamond material; and a non-group-VIII metal fluoride disposed within interstitial spaces between the grains of diamond material and the plurality of diamond nanoparticles. The cutting element is substantially free of a metal-solvent catalyst.

Abstract: Cutting elements for use with earth-boring tools include a cutting table having a base surface and a substrate having a support surface. An intermediate structure and an adhesion layer extend between the base surface of the cutting table and the support surface of the substrate. Earth-boring tools include such cutting elements. Methods for fabricating cutting elements for use with earth-boring tools include forming an intermediate structure on and extending from a support surface of a substrate and adhering a cutting table comprising a superabrasive material to the support surface of the substrate.

Abstract: A ratchet wrench with efficient driver changing function includes a wrench body having a head and a handle, a first slot passing through the first side and connected with a second slot; a ratchet ring, rotatable disposed in the first slot and having a polygonal inner hole for receiving a driver; a direction switching member, disposed in the second slot and having a rotating operation mode and a pressing operation mode; a ratchet block, disposed between the first slot and the second slot that when the direction switching member is at the rotating operation mode, the ratchet ring is driven unidirectionally; a top lid, fixed on the head; and a position limiting plate disposed between the top lid and the head that when the direction switching member is at the pressing operation mode, the position limiting plate engages or disengages the driver.

Abstract: A special tool that can engage and manipulate a Jeep mounting screw commonly known as “Jeep Wrangler Hardtop Freedom Top Targa Mounting Knob Screw” Embodiments may include a handle that can contain indentations or ribs totally or partially extending its length for better grip. The handle abuts a flat head. A pair of screw engagement members are mounted on the flat head, separated, and spaced apart a pre-determined distance. The center region between the engagement members can be part of the flat head. Each engagement member is arc-shaped, or semi-circular in cross-section to fit into the knob screw head. The two engagement members are typically mounted in opposition and each extends approximately ? the circumference of the head. This arrangement allows perfect engagement with the Jeep mount screw.

Abstract: A screwdriver includes a main body and a switch. The main body is coupled to a handle and includes a pair of parallel, spaced apart slots, and a pawl positioned in each slot. Each pawl is biased outwardly by a spring. The switch is pivotable relative to the main body, and the switch includes a groove extending along an arcuate portion of an inner surface. Pivoting the switch in a first direction moves the switch toward a first position in which the groove is positioned in-line with the first pawl. When the switch is in the first position, the first pawl extends outwardly from the slot and engages the internal tooth surface such that application of a torque in a first direction drives a shank in the first direction and application of a torque in the second direction causes the shank to ratchet relative to the main body.

Abstract: A universal multiple bit adapter is disclosed. The adapter is designed for compatibility with most of the available screws in the construction market including Philip screw, Roberson screw, Torx screw and nut drivers. The multiple bit adapter comprises a cylindrical enclosed housing chamber with plurality of openings to enable selective application of the elongated driver bits. The screw driver bits are made from hardened steel and housing chamber is made from any metal or plastic material. The multi-functional bit adapter unit further comprises a clip protection member to hold the elongated driver bits from rotating further during short repair maintenance. This convenient single unit is small, compact and easy to carry in a pocket and can be easily attached to a power tool like a drill or impact wrench.

Abstract: A power driven in-line disposable torque-limiting device having a tool shaft extending axially through upper and lower shanks, and a spring to connect to a nut and a drive shaft, the tool shaft extending from the distal end of the device and a drive shaft extending from the proximal end of the device which mates with a power supply to provide rotational force, is disclosed. The face-to-floor gears within the device provide superior heat management capabilities, thereby reducing ablation and melting as compared to traditional gear arrangements. A fortified connector mount supports a power driven shaft.

Abstract: An embodiment of the present invention provides a jig for detaching a display assembly. The display assembly comprises: a fixing module configured to fix a backlight module in the display assembly; and an absorbing module configured to absorb a display panel in the display assembly such that the display panel and the backlight module are separated from each other by an external force.

Abstract: A power tool having a removable head, a motor, a trigger, and a trigger stop movable between first and second positions. In the second position the trigger is unlocked to permit activation of the motor. A linkage is coupled to the trigger stop and is positioned at a first radial distance from the first central axis. A plurality of actuators extend from the head and are positioned at a second radial distance substantially equal to the first radial distance. When the head is coupled to the handle in a first rotational orientation, one of the plurality of actuators engages the linkage to move the trigger stop to the second position, and when the head is coupled to the handle in a second rotational orientation different from the first rotational orientation, another one of the plurality of actuators engages the linkage to move the trigger stop to the second position.

Abstract: A carrying unit for a source of pressurized air having a frame and at least one wheel on the frame through which the frame can be supported upon and moved over a subj support surface. A conduit assembly is part of a pressurized air handling system on the frame and has an inlet for receiving pressurized air from a source and first and second spaced outlets for discharging pressurized air directed through the inlet. The pressurized air handling system further has an air control system that is changeable selectively into different states. By reason of changing states, the air control system causes at least one of: a) a different volume of air from the inlet to be directed to the first and second outlets; and b) a change in a direction of air discharging from one of the outlets.

Abstract: An ergonomic hand tool holder that supports a tool for use, while being received comfortably in a user's hand in a natural resting angle relative to the wrist, defines forefinger and thumb rest areas on outwardly-facing surfaces of side regions of the holder body, and hand rest areas adapted to engage and rest against the “saddle” of a user's hand when the holder is held with the forefinger and thumb rest engaging the forefinger and thumb rest areas. The weight of the holder and its supported load is distributed to the dorsal saddle area of the user's hand, allowing the user's arm to bear the weight, while the user's wrist and fingers guide, rather than carry, the tool. An ergonomic system may also include a counterweight device adapted to move the combined weight the load toward the hand rest area engaging the dorsal saddle area.

Abstract: Handle configurations are disclosed for powered implements having a shaft, allowing the implements to be holdable by both hands of a user. An exemplary implement has an elongated shaft having first and second end portions. A first handhold is adjustably mounted to the shaft and extends outwardly therefrom. A second handhold is adjustably mounted either to the shaft or to an elongated member coupled to the shaft. The elongated member can include a mounting portion and a handle portion providing the second handhold. The mounting portion mounts to the first end portion at a mounting location. The first and second handholds allow operation of the implement by a user with arms in respective neutral arm positions and hands in respective neutral gripping positions. The elongated member allows transmission of a force applied to the second handhold by the user through the elongated member and to the elongated shaft at the mounting location.

Abstract: A tool handling system including an overhead counter-balance and a control bar. The counter-balance uses a series of complementary springs to provide a counter-gravitational force to a suspended tool. When the user wishes to lift the tool from its equilibrium position, the user is assisted by the counter-gravitational force of the springs such that the tool may be lifted with only a small fraction of the force necessary to lift the tool unaided. The control bar will allow users to keep any cable away from a riser or other structure on which the tool is being used.

Abstract: This invention provides hand operated portable devices for grasping and manipulation of objects as well as methods of their use. Embodiments of the devices of the invention comprise two opposing angled jaw members that are operated by a user-controlled trigger through a hinged linkage lever as well as devices that optionally comprise a locking mechanism allowing locking of the jaw members.

Abstract: A remote presence system includes a robot, a headset, and a computer system. The robot includes a camera mounted on a motorized manipulator and a control system. The headset includes a head position sensor and a display. The computer system configured to perform operations including: receiving head movement data indicative of head movements of a user wearing the headset from the head position sensor; causing, using the head movement data, the control system of the robot to move the motorized manipulator so that the camera mimics the head movements of the user; and establishing a video feed from the camera to the display.

Abstract: A method for energy management in a robotic device includes providing a base station for mating with the robotic device, determining a quantity of energy stored in an energy storage unit of the robotic device, and performing a predetermined task based at least in part on the quantity of energy stored. Also disclosed are systems for emitting avoidance signals to prevent inadvertent contact between the robot and the base station, and systems for emitting homing signals to allow the robotic device to accurately dock with the base station.

Abstract: A programming device receives a number of local coordinate systems from a user. Each local coordinate system is referenced directly or via at least one other local coordinate system to a global machine coordinate system of a motion-controlled machine. The programming device receives from the user, in each case with reference to one of the local coordinate systems, a number of positions to be approached by the end effector and/or a number of obstacles to be bypassed by the end effector. The programming device determines, with reference to the positions to be approached received from the user and the obstacles received from the user in the global machine coordinate system, the path to be traveled by the end effector The programming device stores the path to be traveled by the end effector as a first file so that it can be retrieved again at a later time.

Abstract: A force detector includes a first base part, a second base part, and a pressure detection unit provided between the first base part and the second base part and including a piezoelectric element that outputs a signal in response to an external force, wherein the pressure detection unit has a first member having a portion in contact with the first base part, a second member having a portion in contact with the second base part, and a third member connecting the first member and the second member, a first longitudinal elastic modulus of at least a part of the first member is lower than a third longitudinal elastic modulus of the third member, and a second longitudinal elastic modulus of at least a part of the second member is lower than the third longitudinal elastic modulus of the third member.

Abstract: Examples method and devices for automatic gait transition are described herein. In an example embodiment, a computing system may identify gaits for the robotic device to perform in response to receiving an input for the robotic device to move at a velocity. The system may determine criteria for selecting a gait from the identified gaits for the robotic device to perform based on sensor data of the environment (e.g., slope and terrain) and based on the state of the robotic device. The system may modify the set of criteria based on prior operation of the robotic device in respective environments similar to the environment. Responsive to determining the criteria for selecting a gait, the computing system may determine whether the identified gaits include a gait that enables the robotic device to move at the velocity according to the set of criteria, and provide instructions to operate based on the determination.

Abstract: A dual shaving razor assembly includes an arched central main body and first and second pairs of legs extending down from first and second sides of the main body, respectively, the legs of each pair being in spaced relation to each other. Each pair includes a securing arrangement for securing a shaving cartridge having blades thereto such that each shaving cartridge is adapted to pivot relative to the main body. First and second flexible and resilient wings extend from the first and second sides, respectively, of the main body between the first and second pairs of legs to a position immediately above a respective shaving cartridge held by the respective pair of legs. The wings are adapted to engage an upper surface of the respective cartridge to pivot the shaving cartridge relative to the main body upon application of an external force to the respective flexible and resilient wing.

Abstract: A safety razor comprise a handle and a head portion. The handle has a first end portion and a second end portion. The head portion is removably coupled to the first end portion of the handle and has a guard, a replaceable blade, a replaceable lubrication member, and a cap. The lubrication member has one or more lubrication strips. The cap has one or more openings formed therein and a projection extending therefrom. The projection is configured to extend through the lubrication member, the blade, the guard, and into the handle to removably couple the head portion to the handle. The lubrication strips of the lubrication member extend through the openings of the cap. The safety razor can include a second lubrication member or a skin tensioning member.

Abstract: Provided is a method for producing a separator which method less causes a tear in the separator. The method is a method for producing a separator by slitting, in a direction in which a separator original sheet (12b) being porous is conveyed, the separator original sheet (12b) into a plurality of separators (12a), including the steps of: (a) conveying the separator original sheet (12b) in a state where the separator original sheet (12b) is in contact with a roller (77); and (b) slitting the separator original sheet (12b) at a portion where the separator original sheet (12b) is in contact with the roller (77).

Abstract: A cell cutting device that cuts a mother substrate for display devices includes a fixing unit configured to move in a state where the mother substrate for display devices is fixed on the fixing unit, a cutter configured to perform a cutting process on the mother substrate for display devices and the cutter faces a surface of the mother substrate during the cutting process, a cutter driving unit driving the cutter in a state where the cutter is fixed thereon, and a buffer member arranged on another surface of the mother substrate to correspond to the cutter. The other surface is opposite the surface facing the cutter.

Abstract: A plastic film punching apparatus is improved to make a waste removed reliably. In the apparatus, a plastic film is sandwiched between and punched by male and female blades. The female blade has opposite surfaces which are first and second surfaces. The plastic film generates a waste which is pushed by the male blade to protrude from the second surface. A vacuum source and an opening cooperate with each other to suck air through the opening and generate airflow within the tubular cover, the waste being removed by the airflow.

Abstract: A rotary cutting die for cutting corrugated board to form a die cut product including one or more product ejectors that are specifically configured to avoid crushing the flutes of the die cut product.

Abstract: The present invention relates to functionalized polyorganosiloxanes or silanes for the treatment of lignocellulosic materials.

Abstract: According to one embodiment, the steam pressing apparatus generally comprises a substantially rectangular or square-shaped inner chamber (such as an autoclave) and an outer, generally rectangular or square-shaped structure. In one embodiment, the steam pressing apparatus comprises a hydraulic system used to compress and treat a working material with high efficiency, timing and precision. In one aspect, the steam pressing apparatus comprises a structure and system that allows modularity and scalability for manufacturing final products of varying dimensions. Further, the steam pressing apparatus can be designed to respond to computerized instructions relating to the pressure to be applied, steam to be applied, vacuum parameters, timing of the press operation, thickness of the resultant working material, and other informational inputs.

Abstract: The invention relates to a method for switching a particulate material flow in the construction of models in layers, wherein particulate materials (4) are fed to a subsequent method step from a container (1) having an opening in the direction of a workpiece platform. The particles (14) in the container (1) are exposed to a vacuum and to overpressure.

Abstract: The present disclosure provides a method of stiffening an outer layer of a wet extrudate, where the extrudate has a honeycomb cellular structure. The method includes extruding the extrudate through an extrusion apparatus and directing a substantially uniform flow of fluid onto the outer layer of the extrudate. The method also includes increasing the temperature of a binder material of the extrudate to its gelation point and stiffening at least the outer layer of the extrudate.

Abstract: A pocketformer includes a pocketformer body having a tapered exterior surface. The exterior surface has at least one portion along a length thereof of substantially constant diameter. The pocketformer body has a feature for engaging an anchor base in a concrete structure prior to pouring concrete and a grout ring having a substantially constant inner diameter substantially equal in diameter to the at least one portion. The grout ring has an exterior surface shaped to cause retention of the grout ring in set concrete.

Abstract: The mixing machine is a motorized cement mixer that designed to mix cement in batches of less than 1 cubic foot. The mixing machine comprises a mixing bucket, a paddle insert, a motor, a drive system, a housing, and a control system. The mixing bucket is used to contain the cement or concrete mixture. The paddle insert is an insert designed to go into the mixing bucket. The paddle insert further comprises a plurality of paddles that are used to agitate the concrete mixture to insure efficient mixing. The motor and drive system are used to rotate the mixing bucket to efficiently mix the concrete mixture, and to prevent the concrete mixture from setting in the mixing bucket. The mixing machine comprises a mixing bucket, a paddle insert, a motor, a drive system, a housing, and a control system.

Abstract: A method to make sawing beads by means of laser cladding is disclosed whereby metal matrix powder is molten by means of a laser beam on a rotating sleeve while diamonds are thrown in the molten metal pool. By carefully controlling the temperature of the molten metal pool at or above 1150° C. for less than 200 ms the internal graphitization of the diamonds can be limited. Although some of the diamonds in the sawing bead show internal graphitization it is demonstrated by the inventors that a sawing cord using the bead obtained by the method has an above standard sawing performance.

Abstract: Frame for an electric apparatus for cutting ceramic elements preferably manufactured by a drawing and punching process starting from a metallic plate, being the frame a unique and continuous part in which one or more lined up going through grooves are arranged along which the cutting disc is movable to carry out the cutting of the ceramic tiles, having one or more bulgings directed in a convex form towards the interior part of the frame, being arranged in each of them a first orifice for draining out the water for cooling the cutting disc, second and third bulgings of the metallic plate being aimed at attachment means and abutment means for foldable legs and first bulgings for joining of the guide supporting and leading the cutting disc.

Abstract: Disclosed herein, amongst other things, are various conversion structures for use in a molding system (100, 200). A non-limiting embodiment of the conversion structure includes a standard mold receiver (140, 157) and a mold conversion module (151A, 151B, 151C, 251A, 251B, 251C, 251D, 251E, 251F, 152A, 152B, 152C, 170A, 170B, 170C). The standard mold receiver (140, 57) and the mold conversion module (151A, 151B, 151C, 251A, 251B, 251C, 251D, 251E, 251F, 152A, 152B, 152C, 170A, 170B, 170C) are configured to cooperate, wherein the mold conversion module (151A, 151B, 151C, 251A, 251B, 251C, 251D, 251E, 251F, 152A, 152B, 52C, 170A, 170B, 170C) is receivable in the standard mold receiver (140, 157) for converting a molding configuration of a mold (120).

Abstract: Molded rubber objects may be molded and de-molded by defining both a desired final form for the molded rubber object and a tab extending from the final form of the molded rubber object using a cavity in a mold. Rubber pellets may be dispensed in predetermined amounts at desired location(s) within the cavity to provide the rubber needed to form the molded rubber object. Heat and pressure may be applied to the mold to cause the rubber pellets to fill the cavity defining both the desired final form of the molded rubber object and the tab. After the heat and pressure has been applied, a gripping device may grasp the tab and move the tab in a direction and with sufficient force to peel the rubber object from the mold cavity. If desired, the tab may be removed from the molded rubber object.

Abstract: A foam composite with a skin formed in one shot by charging plastic powders or minute particles together with polyolefin pellets that can be cross-linked and foamed in a mold, and heating the mold while rotating. The composite absorbs almost no moisture, having satisfactory strength, being excellent as an insulating material. Further, providing a covering of a non-foaming or a slightly foaming material to the pellet of polyolefin that can be cross-linked and foamed, and conducting the forming, foamed granules as a core, and a covering of a reinforcing member for the core.

Abstract: Embodiments of the invention are directed to softening amorphous polymeric materials based on a combination of thiol, acrylate, ene and epoxy monomers. These materials can soften to the modulus of tissue, have a sharp transition and are highly tunable. The materials have a glassy modulus of 1-7 GPa and exhibit a rubbery plateau in modulus that can range from 100 MPa down to as low as 0.03 MPa, which is at or below the modulus of tissue. They have potential uses as materials for near net shape processing such as casting, stereolithography, reaction injection molding, fused deposition molding and various other forms of 3D printing.

Abstract: An injection molding device includes a first mold half and a second mold half, which is arranged so that the second mold half can be moved linearly in in relation to the first mold half. A third mold half, arranged between the first and the second mold halves, interacts with the first mold half in a first parting plane to form first cavities and interacts with the second mold half in a second parting plane to form second cavities. The third mold half includes an upper part and a lower part, spaced apart by a slot. A first drive shaft is arranged in an interior of the third mold half. The first drive shaft includes at least one carrier arranged on an arm so that the carrier is movable in a radial direction. The first drive shaft is supported with respect to both the upper part and the lower part by at least one bearing.