Abstract: There is disclosed a construction toy kit including small and large blocks having a hollow open ended box-like base with primary cylindrical outer couplers and inner cylindrical couplers within the base. The size and configuration of these blocks do not allow them to be coupled directly together and the kit includes intermediate blocks capable of so doing.

Abstract: A heat recovery unit for use to preheat fresh air with hot air produced in an industrial process, such as the hot air exhaust from a dryer of a pulp and paper mill. The recovery unit makes use of water circulating from one air/water heat exchanger tank to another air/water heat exchanger tank as heat transfer medium. Hot air whose heat is to be recovered at least in part, flows past a set of revolving discs of metal partially immersed in the water flowing in one of the heat exchanger tanks. The portions of the discs which are exposed to the hot air above the water level transfer the heat they recover to the flowing water. The water which is so heated passes into the other heat exchanger tank where it raises the temperature of an identical set of revolving discs which in turn heats a fresh air intake to provide warm air. The main advantage of this recovery unit is that the heat recovery conditions can be easily adjusted to fit any seasonal fresh air change.

Abstract: An inflatable grinding roller is disclosed which comprises an elastic sleeve tightly fitted over a hollow cylindrical support of which the center is concave so that the sleeve and support together define an inflatable air chamber. The concave section further has a bore section having a radial shoulder at its center so that angular corners are formed, which house packing rings. The ends of the sleeves are inturned over the ends of the support and clamped in position by skirts of a pair of cup-like plugs of which the flat bottoms have axial glands pressing the packing rings against the radial shoulder of the angular corners. A mandrel snuggly fits in the glands, the packing rings and the radial shoulder. It is blocked at one end against the bottom of one of the plugs while the other plug is forced against the first plug by a clamping mechanism. The mandrel has a blind bore communicating with the air chamber by passages through the mandrel, the randial shoulder and the bore section of the concave section.

Abstract: A barbecue cooking device includes a housing having a casing defining a combustion chamber supported centrally therein spaced from the walls of the housing. A heat shield surrounds the combustion casing and is spaced therefrom. A diffuser plate is mounted in the combustion chamber and includes openings in at least a portion thereof for the passage of air under pressure for creating a primary combustion zone. Air is forced against the bottom of the diffuser plate under pressure by an electrically driven fan. The combustion casing has a top open end spaced from the open top end of the housing where a cooking grill is supported. Air also is caused to flow between the combustion casing and the heat shield to supply air to the area at the top of the combustion casing for mixing with heated fuel gas from the primary combustion zone, whereby a secondary combustion zone is created above the combustion chamber and beneath the cooking grill.

Abstract: There is disclosed a rotary knife assembly for shredding straw. It includes a non-cylindrical driving shaft and a plurality of like knifing devices mounted in succession along the shaft, each device having a pair of generally flat shredding parts. Each such part comprises a central portion having a straight edge and radial teeth projecting from the central portion, the latter further having a notch located centrally of the straight edge, notch configured to seat radially over half of the shaft. The central portion also has a boss on one face forming an arcuate shoulder around the notch. The shredding parts of each device are held in coplanar position, when the straight edges meet, by a tube of which one end closely surrounds the shoulders of the bosses, which shoulders extend along a common circle. The same end of the tube abuts one face of the parts thus holding the parts in coplanar position and preventing them from separating along their straight edges.

Abstract: There is disclosed a powered truck-like vehicle having a support base at the back and an apparatus for cutting street or road pavement. A length-wise-extensible boom is mounted at one end on the base so that it can extend laterally of the vehicle. An elongated rail structure is mounted on the other end of the boom in a manner such that it can be moved alongside the boom. A saw carrier, mounted on the rail structure so that it can be displaced along it, is provided with a rotary pavement cutting saw that can be displaced relative to the rail structure to cut pavement. The vehicle may further comprise a second lengthwise-extensible boom fixed to the base so as to project laterally from it at right angle to the longitudinal axis of the vehicle.

Abstract: A pivot structure comprises a one-piece plastic support including a parallelepiped rectangular body having a sidewall and a pivot bracket projecting from this sidewall. It comprises also a one-piece plastic bar section which includes a base plate, a columnar connector having an essentially constant cross-section and projecting from one face of the base plate; an L-shaped connector with a first leg upstanding at one end from one edge of the base plate, spacedly of the columnar connector, and a second leg projecting outwardly from the other end of the first leg, away from the columnar connector. The support section and the bar section are interconnected by a pivot arrangement on both the bracket of the support section and on the free end of the second leg of the L-shaped connector to allow for relative pivotal movement of the support section and bar section about an axis which is parallel to the sidewall of the support section.

Abstract: In an electrical appliance having an electrically conducting housing, defective grounding of the housing may result in a dangerous situation for the user. To prevent such a dangerous situation, the appliance, also having an internal, load circuit, is provided with a safety connector device, which connector device comprises an electric plug having two power contacts through which the load circuit is energized, and two auxiliary contacts. The two latter, auxiliary contacts are respectively connected to two separate points of the housing so that they are interconnected together through an interconnecting circuit including the electrically conducting housing of the appliance. One of the two auxiliary contacts is connectable to a ground for grounding the housing whereby a disconnection of the ground from the housing can be detected by sensing a discontinuity in the interconnecting circuit.

Abstract: There is disclosed a pictorial block puzzle capable of reproducing three different pictures. It consists of a pedestal and of a set of puzzle blocks. The pedestal has a flat upper face and a group of identical plugs projecting from its upper face; the plugs being disposed along orthogonal lines and being equally spaced from one another along those lines. The puzzle blocks are hollow cubes of equal size of which three walls illustrate a portion of one of the three pictures while the other walls are pierced with openings large enough to allow mounting of the cubes around one of the plugs of the pedestal to reproduce one of the pictures when all of the picture portions face up and are properly positioned.