Abstract: Floating aquatic vegetation is harvest from the surface of a body of water. The vegetation is chopped or shredded when floating in situ on the body of water. The vegetation is then removed from the water surface. The chopping, shredding, tearing or other action breaks down the structure of the plants or subdivides them into smaller parts. This reduces the structure of the plant and allows it to be compacted to a much higher density mass so that it can be handled more readily. The apparatus for harvesting the vegetation includes a self-propelled vessel. A shredding head is carried on the vessel for shredding the vegetation as the platform advances thereacross and removing the shredded vegetation from the surface of the body of water. The vegetation shredding means are two rotors arranged in a shallow V arrangement across the front end of the vessel, with the point of the V directed forwardly, in the direction of travel. Rotors arranged in this way assist with the positive tracking of the platform.

Abstract: A trimmer apparatus comprising a trimmer device for use in trimming and edging operations, a carriage to which the trimmer device is mounted to support the trimmer device during use, and a handle for use in guiding the apparatus during use. The trimmer device comprises an elongated support shaft, a power unit mounted at a trailing end of the shaft, a trimmer head mounted at a leading end of the shaft, and a drive connection for connecting the power unit to the trimmer head. The trimmer head has a trimmer blade to operate in a blade plane. The trimmer device has a swivel connection to allow the trimmer head to be swiveled between a trimming position where the blade plane is generally parallel to a support surface supporting material to be trimmed during use, and an edging position where the blade plane is generally at right angles to such a support surface during use. The carriage comprises a frame, and a single support wheel rotatably mounted on the frame to support the frame during use.

Abstract: A round baler having a frame, a baling chamber for forming cylindrical packages of crop material mounted on the frame, a pickup for feeding crop material into the chamber including a tubular rotatable shaft extending transverse of the frame and concentric with a stationary shaft also extending transverse of the frame. The tubular shaft is journalled via a bearing assembly including a generally cylindrical stationary first race and a concentrically disposed generally cylindrical rotatable second race between which races a bearing cavity is formed for seating a series of bearings housed between the first and second races. The first race is affixed to the stationary shaft and the second race is rotatable relative to the first race and affixed to the tubular shaft for rotating in concert therewith relative to the first race. An annular shaped cover encloses the cavity and has a first edge adjacent the stationary shaft.

Abstract: Apparatus for making decorative crafts ropes including a hand-held motorized strand twisting unit and an improved method for rigging, anchoring and spreading strands. Strand twisting unit includes a frame or housing, hand grip, electrical circuit, motor, drive mechanism and twisting hooks. In the rigging process, twisting hooks are aligned and interspaced with a series of anchoring hooks on a strand anchoring unit so as to capture or snag two or more strand segments in a single motion.

Abstract: A composite rubber body is formed by embedding steel cords in rubber and vulcanization-building them. In this case, each of the steel cords is a single steel filament wire or plural twisted steel filament wires obtained by drawing of a wire rod of high carbon steel having a given composition. The filament wires satisfy given relationships between filament diameter and tensile strength before and after the vulcanization and have a retention of loop strength of not less than 55%.

Abstract: Bearing arrangement for an open-end spinning machine has a bearing block attached to bearing supports defined on the machine frame. A seat is defined in the bearing block for receipt of an axial bearing. An intermediate support structure member is removably attached to the bearing block and supporting ring bearings. The intermediate support structure is removable from the bearing block with the supporting ring bearings while the bearing block remains attached to the machine frame through bearing supports.

Abstract: The instant invention relates to a device for the feeding of fibers (51) to the fiber collection groove (23) of an open-end spinning rotor (2). The latter is covered by a rotor cover (3) whose side toward the spinning rotor (2) contains a fiber guiding element (8) the inner circumferential surface (12) of which, in form of a fiber guiding surface, forms a divergence angle (W1) widening in the direction of the spinning rotor (2). The fiber guiding element (8) extends coaxially into the spinning rotor (2). A fiber feeding channel (14) lets out tangentially into its inner circumferential surface (12).

Abstract: A swirl mixer for a fuel nozzle having a mixing duct comprising a center duct and two annular ducts located radially outward therefrom. Each duct has an air inlet and swirling vanes located adjacent thereto. The outlet of the center duct is located entirely within the annular duct located radially outward therefrom, and the airflows within the ducts have significantly different swirl angles tailored to yield low smoke production and high relight stability in a high temperature rise combustor.

Abstract: In a combustion chamber (14) of a gas-turbine group which is arranged downstream of a first turbine (11) and upstream of a second turbine (12) and has a burnerless combustion space, extending between the outflow plane of the first turbine (11) and the oncoming-flow plane of the second turbine (12), and a fuel injector (2) which comprises a fuel-nozzle holder (8), extending transversely to the main flow (1) approximately up to the center axis, and a fuel nozzle (9) arranged in the direction of flow in the center axis and connected to the fuel-nozzle holder (8), the combustion chamber (14) working with premixing combustion, and the inlet temperature of the exhaust gas of the first turbine (11) into the combustion chamber (14) being above the self-ignition temperature of the fuel (13), the fuel injector (2) has means for simultaneously evening out the velocity profile and for lowering the temperature of the flow in the wake region.

Abstract: The present invention relates to a parallel-sheet injector provided with a body about an axis to which there is coaxially connected at least one annular injection element comprising a central annular injection slit surrounded by two other annular injection slits. The central annular slit is fed with a second propellant which enters at the top of the injection element level with said central slit and the other annular slits are fed with a first propellant which enters at the base of the injection element, on either side of the central slit, and passes through an annular homogenization cavity from which it flows towards the annular slits surrounding the central injection slit. The invention also relates to injection elements which may be used within the scope of this injector.

Abstract: An exhaust system for an internal combustion engine including an exhaust duct having a lower portion and an upper portion with a discharge outlet. A pivotable flap is located in the upper portion of the exhaust duct to influence the discharge rate of the exhaust gases passing through the discharge outlet to provide a high rate of discharge of the exhaust gases independently of the operating speed of the internal combustion engine.

Abstract: In a system for treating an exhaust stream, such as the exhaust of an internal combustion engine (10), the exhaust is initially treated by a first catalytic converter (14) and its effluent is cooled in an indirect heat exchanger (18) with an extraneous coolant fluid, i.e., one other than recycled engine exhaust, before introducing the exhaust into a hydrocarbon trap (30) to adsorb hydrocarbons therefrom at least during a cold-start period of engine operation. Such cooling enables utilization of highly efficient adsorbent materials such as activated carbon which otherwise could not be used. Adsorbed hydrocarbons are desorbed from the hydrocarbon trap (30) as the engine exhaust heats up. The exhaust is passed from hydrocarbon trap (30) to a second catalytic converter (34) for oxidation of the hydrocarbons.

Abstract: A engine exhaust system is disclosed for reducing the amount of hydrocarbons emitted during engine start-up (cold-start), before the catalytic converter has attained its effective operating temperature. The system includes a flow diverter, in particular a secondary air jet adapted to direct substantially all of the engine exhaust through a molecular sieve structure during cold-start, and to direct the engine exhaust stream directly from the light-off catalyst to the burnoff catalyst, bypassing the molecular sieve structure after light-off.

Abstract: A compliant master cylinder includes a primary piston and a secondary piston which are movable to provide fluid pressure to effect wheel braking in a vehicle. In addition, the master cylinder includes a compliant assembly which supplies conventional pedal feel and travel characteristics when the primary and secondary pistons are substantially immovable due to isolation the master cylinder from the wheel brakes. The compliant assembly includes a push rod piston that is movable against a selected amount of fluid pressure and spring force while the primary piston remains stationary. The fluid force is supplied by controlling the flow of fluid from behind the push rod piston through a flow restrictive orifice to a conventional fluid reservoir on the master cylinder assembly.

Abstract: Conversion of heat from high-temperature off-gases into useful work is accomplished with a process having first and second stages. The first stage comprises preheating feed water with heat from the off-gases, converting this into steam, passing the steam into a steam expander which drives a first machine, condensing the low pressure exhaust from the expander, and returning the condensate to the preheater to repeat the cycle. The second stage comprises preheating liquid fluorocarbon working fluid, passing the working fluid through a separator and then through the steam condenser, from which a liquid/gas mixture of the working fluid is routed back to the separator, superheating the gaseous working fluid by off-gases, passing the gaseous working fluid into an expander which drives a second machine, condensing the low pressure exhaust from the expander, and returning the liquid fluorocarbon working fluid to the preheater to repeat the cycle.

Abstract: An ice cell (10), provided for the cooling of drinks, comprises a closed hollow body (11) filled with a freezable liquid (16). The hollow body (11) is made at least partially of a transparent material and has least one insert (20) freely movable therein. The insert (20) can have a printing thereon, be colored or marked in any desired manner. e.g., to identify the drink contained in the glass.

Abstract: A portable, thermally insulated container having an isothermal chamber for storing temperature sensitive material. An electronic circuit activates a heater when the temperature in the chamber is below a preselected magnitude and activates a Peltier heat pump to cool the chamber when the temperature in the chamber is above a preselected magnitude. The electronic circuit operates a fan for the intake of air into the chamber while the Peltier heat pump is operating and discontinues the operation of the fan while the heater is operating. Included in the electronic circuit are two sets of dual operational amplifiers. A temperature sensor responsive to the temperature in the chamber controls the operation of one set of dual operational amplifiers for operating the Peltier heat pump to cool the chamber and controls the operation of the other set of dual operational amplifiers to heat the chamber.

Abstract: A cryogenic surgical apparatus comprises: a) a plurality of probes, each having a contact surface, each of which probes is suitable for creating fast temperature changes at the said contact surface; b) temperature generation means, coupled to each of the said probes, being capable of creating cryogenic and above 0.degree. C. temperatures at the said contact surface of the said probe; and c) temperature control means, to control the said temperature generation means.

Abstract: The present invention relates to a method and a system for cooling a piston-driven compressor to permit the compressor to operate with a refrigerant gas, such as freon 22, that would normally cause the compressor to overheat and eventually break down. The method and system comprises connecting a heat exchanger in the cool side of the refrigeration system and connecting it in heat exchange relationship with oil circulated in the compressor to cool the oil to lower the compressor temperature whereby the compressor may operate effectively with the refrigerant gas without overheating.

Abstract: In a refrigerant recovery system, a refrigerant compressor has an inlet for connection to a source of refrigerant to be recovered and an outlet for connection to a refrigerant storage container. A separator is connected in series with the compressor for separating lubricant from refrigerant either before or after passage of the refrigerant through the compressor. A valve or other suitable means is operatively connected between the inlet and outlet of the compressor for equalizing pressure across the compressor during non-operation of the compressor. A pressure sensor is coupled to the refrigerant recovery system and responsive to refrigerant pressure at the lubricant separator. A manual or automatic valve is coupled to a drain on the separator for draining lubricant from the separator during non-operation of the compressor when refrigerant pressure at the separator reaches a selected level during non-operation of the compressor.

Abstract: A portable, electrically powered refrigerant recovery system and method uses a single manifold to reduce fabrication time and costs. A hot gas discharge port in combination with a check valve allows the recovery system to be utilized as a vacuum pump as well as a refrigerant recovery device. A rectangular aluminum oil separator has internal baffles and is located between the inlet and a compressor. A low-voltage control circuit uses a latching circuit to avoid short cycling of the compressor and thereby increase compressor life. The system provides an improved push-pull recovery method in which superheated refrigerant vapor from the compressor is diverted directly to the system being recovered so that the superheated vapor is returned to the unit being emptied to speed the recovery process.

Abstract: A multi-type air conditioner address setting method and address setting device for automatically setting an address with a simple structure. A dummy address sent from an exterior device is stored in an interior device. The interior device determines whether the interior device itself is operating in a designated operation mode. When the interior device is operating in the designated operation mode, the dummy address is set as an actual address. When an address request signal is sent from the exterior device, the set address is sent back thereto.

Abstract: This invention has as its object to provide a method and apparatus for controlling a vehicle air conditioner, which can obtain a combination of an outlet air flow rate V.sub.a and an outlet air temperature T.sub.o, which is desirable for comfort of a passenger, under a condition of air-conditioning control based on a heat balance equation. In order to achieve this object, this invention provides a method of controlling a vehicle air conditioner, including the first step of obtaining, from a heat balance equation, a plurality of combinations of the outlet air flow rates V.sub.a and the outlet air temperatures T.sub.o necessary for maintaining the passenger room temperature to be a predetermined target temperature, the second step of calculating comfort indices each representing the comfort level of a passenger on the basis of state amounts of factors which influence comfort felt by the passenger in the passenger room, and the plurality of combinations of the outlet air flow rates V.sub.

Abstract: A normally closed valve is located downstream of the oil separator to insure that sufficient oil pressure builds up to lubricate the compressor. The valve is responsive to the differential pressure between discharge and economizer such that throttling takes place over a limited portion of the operating envelope.

Abstract: A cross connect hose is coupled between an outlet of an air hydrant at a first end or a blow-out port of a modified three way ball valve, and an outlet of a water hydrant, at a second opposite hose end. A T-fitting mounts a check valve assembly integrated to the second end of the cross connect hose. The check valve assembly includes a spring biased valve disk which seats against an annular check valve body to close off an axial bore leading from the cross connect hose to a counter bore including a series of radial ports opening to the interior of the T-fitting, thereby subjecting the opposite face of the disk valve to the pressure of the water passing from the water hydrant to a downstream snowgun via a water hose. The bias of the coil spring plus the water pressure normally maintains the check valve closed.

Abstract: Machine for making crushed ice drinks comprising a tank with horizontal axis provided at one end with means for dispensing the iced product, and internally housing a refrigerating element consisting of a hollow metal cylinder with double-walled shell housing the evaporator of a refrigerator unit in the gap between the two walls, a transporter screw being housed in the axial cavity of the said cylinder. The outer shell of the said cylinder is surrounded by a stirrer element consisting of one or more radial ribs or fins parallel to the directrices of the cylinder which are made to rotate right around the said cylinder, a series of blades able to exert a positive axial thrust on the product to be delivered towards the said dispensing means also being provided at that end of the said stirrer device facing the dispensing means of the said tank.

Abstract: A water supply device disposed in a refrigerator door includes a first tank, a second tank and a third tank respectively disposed in the door, each of the three tanks having a pipe extending therefrom and each pipe having an outlet extending from an outer layer of the door, a first connecting pipe with a first one-way valve disposed thereto being connected between the first and the second tank, a second connecting pipe with a second one-way valve disposed thereto being connected between the second and the third tank, the first tank having a heating device disposed therein and only the first and the second tank being separated from an interior of the refrigerator by an insulating layer.

Abstract: A bracelet has a guide aperture at one end, a barb at the opposite end, and elongated holes running along its length. The barbed end can be pulled through the guide aperture and then twisted and inserted into an adjacent hole for being captured therein. The holes in the bracelet have rounded corners to enhance the flow of the polymeric material from which the bracelet is formed during an injection molding process and to alleviate the formation of stress points which otherwise occur at the corners of rectangular holes.

Abstract: A foot protector for use in combination with stocking-type hosiery to cushion and protect a wearer's foot is described. The foot protector is preferably knit to include padding in the form of integrally knit terry loops, and has a specially constructed top portion for encircling the wearer's ankle. The top portion extends upwardly to a greater extent proximate the wearer's heel than the instep, and is substantially unpadded. When the foot protector is worn in a layered relationship with a stocking and a shoe, the protector is only minimally visible, if at all, thereby providing enhanced wearer comfort while maintaining the appearance of wearing stockings and shoes alone.

Abstract: A machine for washing articles is provided with a wash process sensor that is capable of measuring a plurality of physical parameters that relate to the progress of a washing procedure. The wash process sensor also monitors the changes in the measured parameters and calculates a value that represents the degree of cleanliness or dirtiness of the articles being washed. In one embodiment, the wash process sensor also directly controls a plurality of devices, such as motors, heaters, dispensers and valves, to directly control the washing process.

Abstract: A lock assembly for locking and unlocking a door comprising a lock bar moveable between a locked and unlocked position, three locks, each of which have lock arms moveable between a locked and an unlocked position, and a linkage connecting the lock arms to the lock bar. The linkage has a first operating configuration whereby the lock bar moves from its locked to its unlocked position in response to the movement of any pair of lock arms from their locked to their unlocked position. The linkage also has a second operating configuration whereby the lock bar moves from its locked to its unlocked position in response to either movement by a predetermined pair of lock arms from their locked to unlocked position or the movement of the third lock arm from its locked to unlocked position.

Abstract: The present invention provides with a water glass layer which prevents oxidation and increases fatigue strength of the alloy. The surface treatment process for preparing the titanium alloy comprises the steps of washing the titanium alloy by alkali cleaning and pickling, drying the alloy in a water glass solution, thereby forming a water glass layer on the surface of the titanium alloy, and forging the titanium alloy.

Abstract: A device for measuring a bending angle of a bent sheet material including a bending angle detector including first and second links arranged symmetrically relative to each other and pivotally connected with each other at one end thereof, a support mechanism for supporting the angle detector on a displaceable ram of the sheet bending press and for displacing the angle detector into an angular space defined by the bending angle of the bent sheet material, and a mechanism for biasing the first and second links into a surface contact with side surfaces of the bent sheet material defining the bending angle.

Abstract: An inching drive system for a mechanical press including a hydraulic motor and gear mechanism, that engages the flywheel of the press. The hydraulic motor is mounted for rectilinear movement toward and away from the flywheel for selective engagement therewith and includes a gear that meshes with teeth on the periphery of the flywheel. A separate hydraulic piston/cylinder arrangement moves the inching drive system into and out of engagement with the flywheel.

Abstract: A floatless liquid level gauge assembly utilizing polymeric resistive/conductive elements is provided which measures the liquid level of partially conductive or conductive liquids in a tank using a three terminal voltage divider network or a two terminal voltage or current network. The polymeric resistive/conductive element(s) extending into the tank and the liquid in the tank provide an electrical path which provides a signal proportional to the liquid level in the tank.

Abstract: A large gyroscope adapted to be used in place of, or in addition, to the counterweights normally used on a crane to keep it from tipping when hoisting a load. The gyroscope is of fixed mass such that all road permits and restrictions can be satisfied without stripping the crane. Once on site, the crane will accelerate its gyroscope to a predetermined number of revolutions per minute (steady state). To induce the gyroscopic moment to counter the tipping moment under load, a motor will rotate the gyroscope with respect to the precession axis, thus inducing a gyroscopic moment. Theoretically, any amount of counter weights can be simulated by controlling the precession rotation and spin of this fixed mass gyroscope.

Abstract: The transmission couples a cam shaft to an output shaft through a plurality of sets of specialized linkages.

Abstract: A motor vehicle transmission system including frictional coupling devices disposed in series connection with respective gear trains between input and output shafts, a one-way clutch disposed in series connection with each of at least one of the gear trains except the smallest gear ratio gear train, for transmitting power from the input shaft to the output shaft, and a shift controller operable during forward running of the vehicle to operate the frictional coupling devices for simultaneous slipping or partial engagement of selected frictional coupling devices, particularly, upon and immediately after starting of the vehicle.

Abstract: A direct drive transmission includes clutches for driving a gear box and a shift controller in providing for improving the shifting of gears within the gear box. The gear box includes a first input countershaft and a second input countershaft. The shift controller includes a motor which is connected between the input countershafts to maintain the speed of the countershafts during shifting of the gears.

Abstract: An alignment apparatus for aligning x-ray images with a predetermined set of axes comprises means defining the axes in the form of a support arrangement which supports, at predetermined positions in space, located in at least two predetermined planes, a plurality of elements which are opaque to ex-radiation. An apparatus is also described for aligning an end effector comprising two spaced guide frames each having two parallel guide members with a carriage for movement along each of the guide members, the carriages being inter-connected by cross members, further carriages being mounted on the cross members, the further carriages supporting the end effector for guide means.

Abstract: An actuating device for a throttle valve of a carburetor used in connection with an automatic transmission, wherein the throttle valve is connected to a throttle shaft and a position of the throttle shaft is adjustable by the accelerator pedal of the vehicle, has a linkage including a first part and a second part. The first part is connected to the throttle shaft and the second part is connected to the accelerator pedal. During an automatic gear shifting operation the first part is displacable relative to the second part with a pressure medium. The first part is preferably a piston with a piston rod whereby the piston is loaded by the pressure medium. The second part includes a housing in which the position is displacably arranged.

Abstract: A structural component (21) is moved axially back and forth with the aid of a closed cam (40A) arranged on a rotating cam carrier (33) for mechanically entraining cam follower rollers carried by the structural component. At least one roller (26) of a pair of rollers contacts one cam surface of said closed cam with a controlled contact force. For this purpose the contact force between the cam follower rollers and the respective cam surface is varied during one cam revolution in such a way that in an angular range (41) of the reversing point (O.T., U.T.) the contact force of at least one cam follower roller that transmits the motion in the respective direction, is increased to such an extent that this force corresponds at least to the inertia force resulting from the brake application or acceleration of the component to be moved. Outside of the angular range (41) the cam follower rollers (26, 27) are kept in contact with the cam surfaces with a minimal force.

Abstract: An automotive differential assembly for a vehicle having a driving case enclosing a pair of driving members operably coupled with a pair of driven members. The driven members are secured to output shafts and the driving members are forcibly driven by a driving shaft having its opposite ends in engagement with the driving case. The driving shaft passes through eccentric or angled apertures formed by cooperating arcuate surfaces provided in opposing surfaces of the driving members. The driving members and the driven members are urged together respectively by at least four dampening springs providing both axial and radial force which dampens or eliminates sudden impact encountered when the shaft moves back and forth within the apertures. The driving members may be loosely aligned and interrelated by pins and enlarged holes, by pins and laterally opened holes or by a key and keyway or channel construction.

Abstract: An improved ratchet wrench includes an upper plate, a lower plate, a base disposed between the upper plate and the lower plate, two ratchets, two trigger blocks, two springs and two baffle elements. Both the upper plate and the lower plate have at least a bent portion at one end thereof. The distance between a middle portion of the upper plate and a middle portion of the lower plate is smaller than the distance between an upper bent portion and a lower bent portion of the plates, such that the distance between the middle portions is equivalent to the distance between the bent portions of the upper and lower plates multiplied by a cosine of the angle of the bend. By such an arrangement, the upper plate and the lower plate are identical in shape and length, and hence manufacture of the ratchet wrench may be speeded up and costs reduced.

Abstract: A hand tool has an elongated shank with a handle at one end and a bit holder at the other end, the bit holder including a cylindrical body having a distal end surface and an axis, the body having an axial bore formed in the end surface of non-circular transverse cross section and terminating at an inner end surface. A neodymium permanent magnet is freely received in the bore and retained against the inner end surface by a thin circular retainer, formed of metal or plastic, which is interference-fitted in the bore. Both flat, disk-like and concave, bowl-shaped retainers are disclosed. A shock-absorbing cushion may be disposed between the magnet and the inner end surface of the bore. A bit formed of magnetizable material is mateably received in a socket portion of the bore and retained in place by the magnet. The portion of the bore receiving the magnet may have a different cross section from the socket portion. The magnet may be disposed in an encapsulation which interference fits in the bore.

Abstract: A head trimmer machine for cutting off excess material from a cylindrical portion of a blow molded bottle includes a fixture, a spindle rotatably mounted in the fixture, a cutting head attached to the spindle for rotation therewith, a cutter mounted to the cutting head, and a vacuum source for collecting the trimmed material by suction. The cutting head has a central passage so that it can fit down over the head of the blow molded bottle. The cutter is supported in the cutting head for movement between retracted and extended positions. In the extended position, the cutter extends into the central passage of the cutting head to cut the head or other excess material from the neck of the bottle as the cutting head turns. The spindle includes a central passage aligned with the central passage of the cutting head and the excess material is removed by being drawn through these passages by a gaseous flow created by the vacuum source.

Abstract: Relatively thick-walled (or solid) tubular members may be cut by a cutting tool which includes an annular frame having a rotatable ring which is adapted to surround the tubular member to be cut. A pair of cutting assemblies are radially connected to the rotatable ring of the annular frame so as to be orbitally movable about the tubular member to be cut in response to rotation of said rotatable ring. The radial cutting assemblies carry a bit subassembly (preferably a pair of generally radially opposed cutting assemblies) for cutting said tubular member. A drive/indexing assembly is provided so as to rotate the rotatable ring (and thereby cause the radial cutting assemblies to move orbitally about said tubular member), and indexing the bit radially toward a central longitudinal axis of the tubular member in response to orbital movement of the radial cutting assembly.

Abstract: A screw shaft supporting structure capable of absorbing elongation of a screw shaft due to changes in environmental temperatures irrespective of the position of the rotary blade on said screw shaft is disclosed. In the sheet material cutting device, that portion of the screw shaft which is supported by a bushing and another portion thereof supported by a frame end absorbs elongation of the screw shaft due to heat. When the supporting member holding the rotary blade is positioned at A in FIG. 1, elongation of the screw shaft due to thermal expansion is absorbed in a gap formed between the stepped portion of the screw shaft and the frame end. When the supporting member holding the rotary blade is positioned at B in FIG. 1, elongation of the screw shaft due to thermal expansion is absorbed in a gap S1 formed between the stepped portion of the screw shaft and the bushing.

Abstract: A saw blade is provided with recurring groups of teeth. Each group of teeth includes one straight tooth, an even number of high set teeth, and an even number of low set teeth. Distances from all of the teeth in the group to a corresponding, immediately preceding teeth are different for all of the teeth. Distances from all of the teeth in the group to a preceding tooth of the same height are different for each tooth. Distances from all of the set teeth in the group to the nearest preceding set tooth with the same set are different for each set tooth. No high teeth are immediately adjacent.

Abstract: A method and apparatus are provided for cutting a decorative groove in a matboard. The matboard is positioned adjacent a guide. A carrier is adapted to be moved along the guide with two blades oriented in separate planes which intersect each other and which lie at an oblique angle relative to the matboard. One of the blades is inserted into the matboard at a selected first depth. The carrier is moved along the guide for a predetermined length of travel to make a first cut in the matboard defining a first side of the groove. The blade is then retracted. Then the other blade is next inserted into the matboard to a selected depth at least intersecting the first cut. The carrier is then moved back to the initial location to make a second cut in the matboard defining a second side of the groove. In a preferred embodiment, the tips of the blades are offset from each other relative to the length of the groove.