Abstract: A temperature controlled conveyor system where a non contact sensor detects the presents of a product to be treated and then supplies a signal to a control device to regulate a radiant heating device. Also the conveyor has an adjustment device to set the optimal distance between the radiant heater and the article being treated.

Abstract: A mesh tubular basket is arranged for mounting about a support tube and secured at each end of the mesh basket by strap members to position canvas type shoes and the like within a clothes dryer during a drying procedure. The support tube is arranged with a spring-biased sleeve, having a collar member to secure the sleeve if desired in a biased orientation against an interior wall of a drying machine drum.

Abstract: A direct-fired kiln for drying lumber having a reversible powered air-mover mechanism for producing air circulation within the interior of the kiln in either of opposite directions. Selectively controlled air withdrawal conduits returning air to a fuel burner outside the kiln are adjusted so that air is always withdrawn from the side of a load within the kiln where circulated air is exiting from the load.

Abstract: A very long wearing material to replace regions that erode rapidly in the heels of outdoor shoes. The material is made by embedding relatively large, round, wear-resistant particles in a very hard urethane binder. Applications include both applying the material directly to the heel as a paste with curing in situ and casting in molds for attachment to the heel with an adhesive.

Abstract: In a device for adjusting the forward lean of upper (3) of a ski boot with a pull and pressure piece (6), which is supported on bottom shell (1) and upper or cuff (3), in which the distance of supporting surfaces (11, 12) on pull and pressure piece (6) interacting with upper or cuff (3) is adjustable for support on bottom shell (1) in lengthwise direction of pull and pressure piece (6), supporting surfaces (11, 12) interacting with upper or cuff (3) interact through the interposition of a damping element (13) made from elastomeric plastic or rubber with an upper and a lower stop face (14, 15) on upper or cuff (3).

Abstract: The invention pertains to an article of footwear having a backtab pull and a tongue pull on an upper of the article of footwear. The backtab pull and tongue pull assist the wearer in the donning and removing of an article of footwear, in particular an athletic shoe having a molded dynamic fit. The backtab pull includes a strap affixed to the posterior of the article of footwear and the tongue pull includes at least one hole, and preferably two holes, incorporated into an extended tongue portion of the upper.

Abstract: A rear loaded picture frame of four integral joined side members having rebates with resilient flaps thereon movable between a first position allowing loading of a picture element and backing board and a second position wherein free edge portions on the flaps are resiliently deformed against the backing board to hold it and the picture elements in position in the rebate.

Abstract: A detachable plaque for a cap having a visor and an adjoining crown portion is provided. The plaque generally comprises a flexible plastic sheet-like member having a live hinge or crease which defines a boundary between an upper portion of the sheet-like member and the lower portion of the sheet-like member, a first coupling or mating device incorporated on the upper portion of the sheet-like member for detachably engaging a mating member on the crown portion of the cap, and a second coupling or mating device incorporated on the lower portion of the sheet-like member for detachably engaging a second mating member on the visor of the cap. The first and second coupling means may be snaps and/or snap receivers, sockets and/or domed plugs, Velcro hook and/or loop fasteners, etc. In accord with one embodiment of the invention, the flexible plastic sheet has an aperture in at least the upper portion for receiving a piece of cardboard or paper on which a message or information is printed.

Abstract: A display device which can be used in combination with, for example, telephones, computers, keyboards or other similar devices to conveniently display useful information such as speed dialing numbers. Also described is a combined device and display device and methods of using the display device described herein.

Abstract: A display system for two-dimensional displays wherein images are applied (e.g., photographically, printed or the like) to transparent sheets and transported through a viewing machine, the sheets being sequentially positioned in a back-lighted viewing window. The sheets are suspended from rods and stored behind the back-lighting area. The rods are arranged in a desired sequence in a storage rack having an entrance and exit. A chain is entrained on a circuitous pathway through the machine. The pathway starts at the exit end of the storage rack referred to as a pick-up station, then passes over the back-lighting area, extends downwardly between the back-lighted area and the window, passes under the back-lighting area and behind the stored display sheets to a return station that receives the sheets and directs them to the entrance to the storage rack, and then back to the pick-up station. The images are inverted on the sheets with the sheets suspended from the rods, e.g.

Abstract: A buffered means for attaching a first device to a second device. The attachment means includes a camming surface. The invention provides a buffer element between the attachment device camming surface and the area to which the attachment device is affixed.

Abstract: A fish handling net comprises a body portion having a triangular opening. The body portion can be formed from a net material or from waterproof plastic sheet material such as PVC which has been perforated to provide drainage holes.The body portion is provided with attachment means comprising weighing rings, and VELCRO.RTM. strips along each side of the body portion. The weighing ring is attachable to a projection of a sleeve which is clamped to a pole.

Abstract: An illuminated fishing pole is provided, which consists of an elongated tubular tapered transparent rod. A handle is attached to a back end of the rod. A mechanism for producing illumination is carried within the handle. A structure is for transmitting the illumination from the illumination producing mechanism through the rod to approximate a front tip end. A fisherman will have an advantage of seeing the front tip end of the rod illuminated while fishing at night.

Abstract: A synthetic resin frame, having a single foot extending laterally from it, has a roller mounted for rotation about a bearing element that extends into holes in the sides of the frame. A combination line guard and bearing-retaining element is snapped over the frame. The ends of the line guard and bearing-retaining element hold the bearing in position, while openings in the line guard guide the line and substantially prevent it from contacting the synthetic resin. The line guard and bearing retainer is formed of material more wear resistant than that of the frame.

Abstract: A lure has an opening part at a front end of a main body. A water resistance part and a connecting part are provided in the opening part. The main body is made from a pair of shell members combined together. Each shell member has a recess part for forming the opening part, an inclined face for forming the water resistance part disposed below the recess part, another recess part for forming a hollow part within the main body, a wall for dividing the opening part and the hollow part and a slotted hole which is provided at a front side of the wall and which communicates with the opening part. The slotted hole is so formed as to be located at the position of a gill in an appearance. Each shell also has the connecting part below the opening part in the main body. Accordingly, it is possible to provide a lure in which the reality of the lure to fish, a living bit or the like is improved without deteriorating an activity or moving ability of the lure.

Abstract: A fishing lure is described which is wholly or in part comprised of hydroxylated polyvinyl acetal sponge. The sponge may include a fish attractant. The lure looks and may smell like natural bait, and achieves a desired more natural action of a lure with a much longer lived attractant functionality.

Abstract: The invention takes the form of a hydrodynamic plane which carries a fishing line up and down along a weighted downrigger trolling line. The position of the plane is controlled by the fisherman through the fishing line which is releasably clipped to a leader attached to the trailing edge of the plane. Whenever there is a mild amount of tension on the fishing line the plane is held in a down-planing position so that the device will dive and be held against the downrigger weight by the hydrodynamic force. The weight of the plane is balanced so that when the tension on the fishing line is relieved or if the fishing line is released from the friction clip, the plane will automatically pivot to an up-planing position and rise to the surface. Thus, the plane will automatically rise to the surface when a fish strikes the hook, or the fisherman can make the device rise to the surface on command without releasing the fishing line so that he or she can check the bait or the lure and send the device back down again.

Abstract: A net trap incorporating a net attached to both a frame and a bar, which is slidably attached to the frame. A handle is attached to the frame. A release means in the handle allows the bar to slide relative to the frame as urged by an elastic means, thereby closing the net and imprisoning its contents.

Abstract: A creeping plant supporting frame assembly includes a plurality of upright support frames, which are each comprised of a plurality of elongated upright rods spaced from one another around a circle and connected together by a spiral tie bar around the periphery, anchor rods for supporting the upright support frames on the ground, a meshed head frame supported over the upright support frames for climbing creeping plants, feeder bottles respectively suspended on the upright support frames for watering and feeding liquid fertilizer, and baskets and hangers respectively hung on the upright support frames for carrying fruits.

Abstract: A vertical or columnar planter is disclosed which includes a self-contained water distribution system. The planter includes a generally vertical, elongate planter body having openings at intervals along the side walls of the body. The planter is filled with soil or another growing medium which forms a continuous column within the planter. Plants are grown in openings distributed along the side walls of the planter. Each opening is configured with a protruding lower lip and an indentation along its top edge to help retain the growing medium within the planter body. A hierarchical watering system is built into the planter. The watering system supplies water for a greater time interval to the top of the planter and progressively lesser time intervals in regions lower down on the planter. The watering system helps balance the downward flow of water through the planter, providing an optimal supply of water to all plant-growing locations.

Abstract: A washing and cleaning machine and method of cleaning to debur and completely remove all types of contaminants such as oil and grease. The workpieces to be cleaned are loaded into a fixture chamber, and the chamber is filled with an abrasive cleaning media such as steel pins. The workpieces are directly vibrated through fixturing in the confined media as working fluid continuously flows through the fixture chamber, removing contaminants.

Abstract: A machine 80 for polishing a surface of a glass plate 20, comprising a polishing belt 1 provided with a polishing layer in an outside surface thereof, a traveling unit 2for traveling the polishing belt 1, a flatly supporting unit 21 for flatly supporting the polishing belt 1 in a polishing area for the glass plate 20, and a holding and pressing unit 31 for holding the glass plate 20 to be polished and for pressing the held glass plate against the outside surface of the polishing belt 1 flatly supported by the flatly supporting unit 21, and further comprising a swinging unit 61 for relatively swinging the glass plate 20 relative to the polishing belt 1 in a direction parallel to a plane in which the polishing belt 1 is supported by the flatly supporting unit 21, and in a direction traversing to a traveling direction of the polishing belt 1, the glass plate being held by the holding and pressing unite 31.

Abstract: In order to grind clothing of a carding element, such as a cylinder of a textile machine, such as a card, during operation of the cylinder, a slide is moved back-and-forth across the clothing. The slide is reciprocated back-and-forth by an inner run of a drive belt guided in guides such that the drive belt together with a grinding element, like a grinding stone, closes a housing totally covering the arrangement. As a result, neither grinding dust nor fibers can enter the housing. Each time the grinding stone moves past a grinding member, such as a diamond rake or diamond roller this grinding stone is re-ground, so that the clothing is maintained sharpened by the continuous grinding operation and the grinding stone itself is cleaned or re-ground by the grinding member. Also, structure detects the degree of wear of the grinding element so that upon reaching a predetermined value such grinding element can be replaced.

Abstract: A telescopic grandstand is provided including a central support structure and two sets of interconnected telescopic grandstand seating tiers. One set of tiers is located adjacent one side of the support for telescopic movement between a closed position adjacent the vertical upright portion of the support and an open use position wherein the tiers of the set form a stepped configuration which extends outwardly from the adjacent side of the support and downwardly from the top of the vertical portion of the support. The second set of telescoping seating tiers is similarly located adjacent the other side of the vertical portion of the support. The entire unit is movable in directions normal to the sides of the vertical portion of the support, and means are provided for rotating the unit about a vertical axis.

Abstract: Ridge cap means adapted to secure one or more roof panel members to a modular building structure. Such a ridge cap means has a horizontally disposed base portion that is adapted to engage a supporting member incorporated in, and presented from, the modular building. An inclined, plate portion is supported from the base portion. The plate portion is adapted to receive, and support, the roof panel. A locking member frictionally secures each roof panel to one or more inclined plate portions.

Abstract: A vacuum system is utilized for preventing radon gas from entering the basement of a home. The gas is drawn from the interior of the basement walls, the exterior of the basement walls and from underneath the floor into a drain tile under the floor where the gas is then evacuated to vent pipes extending to the top of the home where the gas is vented to the atmosphere. A water trap is provided in a pipe extending from a first drain passageway between the basement wall and the exterior edge of the basement floor to the drain tile under the floor preventing radon gases from moving upwardly into the basement. The first drain passageway and floor and wall are sealed against migration of gases upwardly from under the floor.

Abstract: A structural wall unit for retaining wall structures of in ground swimming pools, whereupon assembly of a plurality of wall units in series, a circuitous pathway is formed which defines the swimming pool shape. In accordance with one aspect of the present invention, each unit includes end surfaces comprising folded portions at the corners thereof for reinforcement of the wall unit, at least one of the surfaces being formed for engagement with a corresponding end surface of an adjacent unit. The units are fastened one to the other so as to form the circuitous wall structure. Each unit includes a base or lower wall for supporting the unit in an upright position and a gusset plate having apertures adapted for cooperation with matching holes on a pair of adjacent folded portions of an end surface, each of the folded portions being adapted to overlie the gusset plate.

Abstract: The present invention relates to office panelling systems and in particular to office panelling systems having improved construction. The frame of the panels provides an improved electrical power feed arrangement within the panel as well as more convenient access to power outlets within the panel. The frame is also designed for enhanced cooperation with filing cabinets and filing bins to provide lower support for such cabinets and bins when hung from the office panel, particularly when the bin or cabinet is intermediary vertical supports of the frame.

Abstract: A cable management apparatus is used in conjunction with a wall panel system having an internal space. The apparatus comprises a plate with spaced apart retainer members extending outward from the plane of the plate. Each retainer member defines at least a partial enclosure sufficient to prevent cables placed therein from slipping out laterally. The plate is fastened to the wall panel system at a desired location within the interior space to hold and separate cables.

Abstract: The present invention relates to improvements in office panelling systems and the distribution of wires therethrough. A specialty lay-in wire is stackable above other panels and has an open channel for receiving wires, cables and the like without threading through the panels.

Abstract: The invention provides a building block which in its operative position has a front (10) and back (12) surface, a top (14) and bottom (16) surface and two end (18) surfaces and a groove (22) formed in both the top and bottom surfaces. The groove (22) is shaped to receive a complementally shaped key (24) in a friction fit manner when one block is placed on top of another.

Abstract: According to the invention, there is provided an exterior wall unit for an exterior wall of a building structure, which comprises a siding member (10) made of a metal and one or more porcelain tiles (20) corresponding in size to and fitted to the outside surface of the siding member (10), the siding member (10) having the outside surface formed with engaging means (16) extending in the horizontal direction for engagement with the tile or tiles (20), each tile (20) being formed with engaging means (23) for engagement with the engaging means (16) of the siding member (10), each tile (20) being coupled to the outside surface of the siding member (10) to be integral therewith with the engagement of both the engaging means (16, 23).

Abstract: A flooring support system comprising a floor having an upper surface and a lower surface, a base surface, a floor support for supporting the lower surface of the floor in spaced relation above the base surface, the support including a resiliently compressible body having a first end surface engaged with the lower surface of the floor, a second end surface facing opposite the first end surface and engaged with the base surface, a central portion located intermediate the first and second end surfaces, and pneumatic spring means in the central portion for storing energy transferred through the floor to the body and for returning to the floor from the body substantially all energy transferred to the body through the floor, the pneumatic spring including a mechanism for affording resilient deflection of the first end surface toward the second end surface and pneumatic air cells for resisting deflection of the first surface toward the second surface.

Abstract: The present invention includes panels having longitudinal sides configured for lateral engagement of the panels an include a drainage channel hidden by a jut or wing of the panel arranged immediately beside the channel. The channel collects possible infiltrations through joints arranged between the laterally coupled panels. The panels also include a slot at one end and an extension at the other end which, when are coupled together by overlapping and axial sliding. The panels have a space in which a securing staple is arranged to secure the panels to a support structure. The staple is spaced apart from the channel and hidden by the jut of the next lateral panel, so that the securing devices are isolated from the outside. In a preferred embodiment, one of the sides of the panels has a cross section with a smaller cross section than the rest of the panel so that it can be coupled by longitudinal sliding into a slot of complementary form arranged at the other end of the panels.

Abstract: A retaining wall building block comprises a face wall and two side walls extending rearwardly from the face wall from the opposite ends thereof with the face wall and two side walls being shaped and arranged such that the block has a generally C-shaped configuration as viewed from above. An ear projects outwardly from one of the side walls. A notch is provided in the other of the side walls for receiving the ear of a second building block of identical construction when the blocks are placed in side-by-side relation. The blocks may pivot relative to one another about a generally vertical axis such that a plurality of blocks of substantially identical construction may be selectively arranged in a variety of configurations ranging from a generally straight-line configuration, a generally convex configuration and a generally concave configuration.

Abstract: The present invention provides a preformed modular wall panel for constructing the exterior walls of a building and a method of assembling such wall panels. The wall panel comprises a rigid frame, a sheet of exterior finishing material attached to the exterior periphery of the frame and a sheet of insulating material held in slots in the frame intermediate the exterior and interior peripheries of the frame. This spaced-apart relationship defines a closed-air space between the exterior sheet and the insulating sheet. A cementitious exterior sheet attaches to the exterior periphery of the frame by a plurality of projections extending from the frame. The projections are embedded in a fluidal cementitious material held in a casting form. The cementitious material cures into a solidified exterior sheet. A method and apparatus for manufacturing the panel and a method and apparatus for erecting a wall of the panels are disclosed.

Abstract: An apparatus for discharging the contents of bags containing flowable material includes a frame, with a pair of bag spikes mounted generally parallel to, and coplanar with, one another on the frame. A pair of bag pans is movably mounted on the frame so as to be engageable with the bag spikes. Each of the pans is selectively pivotable around a respective axis defined by each of the bag spikes. The bag pans are movable between a first, load/unload position wherein the bag pans are out of engagement with the spikes, and a second, engaged position wherein the bag pans are in engagement with the spikes. A knife assembly is provided that includes a knife arm having a first end pivotably mounted to the frame, and a second end upon which is disposed a knife member. The knife assembly is pivotable between a severing position wherein the knife member extends between the bag pans, and a rest position wherein the knife member is out of the plane defined by the bag pans.

Abstract: A method and apparatus is for inserting a flat flexible bag having a rigid fitment into a bottle through a small bottle finish, and expanding the bag inside the bottle. The flat flexible bag can be grasped and oriented via the fitment utilizing a friction chuck. The fitment also enables the bag to be sealed to the bottle in an air-tight manner by interference fit. A biased plunger extends into the bag through the fitment. The plunger helps push the bag through a funnel while a vacuum is applied to the bag through the plunger. The funnel includes two angled plows which cause the bag to fold in a "C" shaped configuration. This insures reliable expansion of the bag upon releasing a blast of air into the bag. During the expansion process an air vent channel permits escape of the air between the bag and the bottle. An exemplary package formed utilizing this method and apparatus is a squeeze pump package having a thin film beam spring vent valve.

Abstract: A method of and apparatus for bagging ice cubes produced by a plurality of cubers with only one bagger when the cubers are stacked side-by-side with the ice produced by each cuber falling into one of two hoppers. The ice is moved from each hopper alternately to the bagger. There each batch of ice cubes is dropped into a bag, the bag sealed, and moved to a storage bin positioned below the bagger. The bags have a short side and a long side with the long side having holes to allow the bags to be supported by horizontal parallel rods extending through the holes. A platen is moved against the short side of a plurality of bags hanging from a first set of parallel rods extending through the holes in the long side of the bags. The air pressure between the platen and the short side of the bag is reduced to cause ambient atmospheric pressure to hold the short side of the outside bag against the platen.

Abstract: A transformer unit mountable above the cutting deck of a mid-size, walk behind rotary mower, effectively converts the mower into a riding mower. The transformer unit is configured so as to allow an operator to be seated above the cutting deck, while still being able to comfortably control the mower by means of the original operator control handle, which is relocated by the transformer unit to the front end of the mower. The transformer unit comprises a support frame which is affixed to a cutting deck support structure. The support frame includes a vertically tiltable floor unit that extends over the top of cutting deck. An auxiliary operator control handle attachment fixture is mounted to the forward end of the support frame adjacent to the front end of the mower and is configured to engage and support the operator control handle, such that the operator control handle extends above the cutting deck adjacent to a position where the operator is to be situated.

Abstract: In a method for connecting two yarn ends to one another, each yarn end is held at two longitudinally spaced apart points and an axial untwisting is introduced. These two untwisted ends are then joined together head to tail by gripping the central portion. There is next induced in the untwisted portion of each end between the central gripped portion and the respective yarn holding point by means of which the untwisting was induced, an axial excess untwisting with simultaneous winding of the free fibre ends about the portion subjected to excess untwist. The twist is retransferred by releasing the central portion during this operation.

Abstract: A reverse stranding apparatus for the reverse stranding of conductors. The apparatus comprises a stationary divider element, a twisting element rotatable in different directions, and a central element disposed between said parts, and peripheral tubes surrounding said central element, the central element and the peripheral tubes being pressed against each other at least during the twisting step of the conductors and the conductors to be stranded being adapted to pass through at least the peripheral tubes. To attain high speeds of rotation, the peripheral tubes and the central element are united in a tube packet by a reticular fabric enveloping the peripheral tubes and extending substantially over the entire length of said peripheral tubes.

Abstract: A control system for hydraulically controlling variable engine structures is disclosed in which the control system utilizes hydraulic fluid identical to that used by the aircraft hydraulic control circuit. A high pressure hydraulic pump, driven by the aircraft engine, may be interconnected with the aircraft hydraulic control circuit, or may be associated with a separate fluid reservoir, to supply pressurized hydraulic fluid to the actuators for controlling the variable engine structures. The engine control circuit also includes a hydraulic pressure modulator to modulate the pressure of the fluid supplied to the actuator and a selector connected between the high pressure pump and, the modulator and the aircraft control circuit to selectively supply the high pressure hydraulic fluid from the pump to either the engine control circuit, or to the aircraft control circuit.

Abstract: In order to facilitate enhanced starting of gas turbines at very high altitudes where the cost must be low and the design must be simple, a turbine engine (10) is disclosed. It includes a turbine wheel (12) coupled to a compressor (14) for driven movement, a nozzle (16) for directing gases of combustion at the turbine wheel 12), and an annular combustor (18) defining an annular combustion space upstream of the turbine wheel (12) in fluid communication with both the compressor (14) and the nozzle (16). The combustor (18) receives fuel from a source and air from the compressor (14) and combusts them in the combustion space to generate the gases of combustion. The combustor (18) is defined by an annular outer wall (20), an annular inner wall (22), and a radial wall (24) extending therebetween opposite the nozzle (16).

Abstract: In order to enhance fuel injection efficiency, and particularly to atomize low fuel flows at high velocity with low fuel pressure, a fuel injection system 24 for a combustor 22 of a turbine engine 20 has an air blast tube 48 and a fuel supply tube 76. The air blast tube 48 is mounted at an acute angle relative to a wall 26 of the combustor 22 and has a first end 50 in communication with the combustor 22 and a second, enlarged end 52 disposed at an acute angle to an axis 54 of the air blast tube 48 in communication with a source of compressed air externally of the wall 26 of the combustor 22. The air blast tube 48 is operable to deliver compressed air from the source into the combustor 22.

Abstract: A fuel injector system for a combustor of a gas turbine engine includes first and second fuel injectors rendered operative to discharge fuel to the combustor during a high power regime of engine operation and rendered non-operative during a lower power regime of engine operation. The first and second fuel injectors include respective first and second fuel discharge passages in fuel flow communication to one another and to the combustor via associated fuel discharge lips to sustain a flame region. The first and second fuel injectors are operatively associated with respective first and second air discharge means having air discharge lips for discharging air to the combustor for sustaining the flame region therein. When the fuel injectors are rendered non-operative, different pneumatic pressures are established at the fuel discharge lips to purge fuel from the fuel injectors to the combustor.

Abstract: The present invention relates to a device for controlling the speed of the engines of an aircraft. According to the invention, the mechanical transmission (8) between the servomotor (6) and the throttle lever (4) comprises a coupling which can be overridden by the deliberate action of the hand of the pilot on the throttle lever (4), and the computer (18) comparing the speed to be reached X OBJ and the limit speed of the engine X LIM and supplying a signal which is representative of the datum speed of the engine X CONS, is linked to a computer (28), linked to the computer (22) supplying a signal which is representative of the speed of the engine corresponding to the position of the throttle lever X(TLA), said computer (28) supplying, from signals from the computers (18) and (22), a signal which is representative of the demanded speed of the engine X COM, such that:if the relationX(TLA)-.DELTA..ltoreq.X CONS.ltoreq.X (TLA)+.DELTA. (1)(where .DELTA.

Abstract: A control system for an internal combustion exhaust gas heater provides air and fuel to the heater in appropriate proportion to be rapidly ignited therein upon activation of the control system. When flame is present in the heater, the proportion of air and fuel is adjusted to provide maximum heat energy from the heater to the exhaust gas for a predetermined period of time.

Abstract: In an exhaust system for an internal combustion engine having a main exhaust conduit with a catalytic converter arranged remote from the engine and a bypass exhaust conduit which includes a start-up catalytic converter arranged close to the engine and joins the main exhaust gas conduit ahead of said remote catalytic converter, an ejector structure is arranged in the main exhaust gas conduit within a housing defining a suction chamber in communication with the bypass exhaust conduit for drawing gas through the bypass exhaust conduit into said main exhaust gas conduit whenever exhaust gas flows from the engine through the main exhaust gas conduit and a main exhaust conduit valve is arranged between the ejector structure and the junction of the main and the bypass exhaust conduits which is closed during start-up operation of the engine to thereby force the exhaust gas to flow through the suction chamber and the bypass exhaust gas conduit via the start-up catalytic converter.

Abstract: A hydraulic drive system for construction machines comprising a valve group (52) including a plurality of directional control valves (9-13) of center bypass type, a center bypass line (2a) for connecting in series center bypasses of the plural directional control valves to a low-pressure circuit (29), a plurality of bleeding-off variable restrictor means (56) respectively disposed in the center bypasses of the plural directional control valves, a pressure compensating valve (20) provided in the center bypass line, and first and second differential pressure detecting lines (22, 24) connected to the center bypass line for transmitting a differential pressure to the pressure compensating valve.