Abstract: An apparatus for supplying gas to a liquid, especially for the aeration of water, comprising an aeration element in the form of an elastomeric hose, for example of rubber or rubber-like material, that can receive compressed air. The walls of the hose have perforations fine slits, or other apertures. A portion of the hose extends around a filling member. This portion of the hose, with the filling member, is received in a groove of a retaining member. An opening of the groove is narrower than this portion of the hose.

Abstract: An apparatus for aerating water or other liquid is provided, and includes a flexible hose of rubber or other elastomeric material for disposal in the water or other liquid. The wall of the hose has a perforation, fine slits, openings or the like via which gas can escape into the liquid. A tubular connector is introduced into one end of the hose via which air can be supplied to the hose. That end of the tubular connector facing the interior of the hose has a flattened configuration and extends in the direction of the longitudinal axis of the hose. The wall of the tubular connector is provided with apertures for the passage of air.

Abstract: The invention relates to an apparatus for the introduction of gas into a liquid, especially for the aeration of water, and includes an elastic hose or tube that is disposed on a rigid profiled support member, whereby the tube has elastically expandable slits and whereby the air can escape into the water, in the form of small bubbles, through the expanded slits. The diameter of the tube is greater than the outer periphery of the profiled support member without recessed area or areas.

Abstract: A pin for playing ninepins or for bowling is provided. The base portion of the pin is detachable from the pin body and is replaceable. The base portion comprises a material that is more robust, wear resistant and/or has a higher resistance to scoring than does the remainder of the pin. The base portion can be provided with a reinforcement. The base portion has an annular support surface with at least one radially extending notch, a sharp inner edge, and high static friction to effect an improved ground adhesion.

Abstract: An apparatus for aerating water or other liquid is provided, and includes a flexible hose of rubber or other elastomeric material for disposal in the water or other liquid. The wall of the hose has a perforation, fine slits, openings or the like via which gas can escape into the liquid. A tubular connector is introduced into one end of the hose via which air can be supplied to the hose. That end of the tubular connector facing the interior of the hose has a flattened configuration and extends in the direction of the longitudinal axis of the hose. The wall of the tubular connector is provided with apertures for the passage of air.

Abstract: A holder is provided for an aeration system for introducing air or gas into a liquid. The aeration elements of the system include an elongated support body on which is disposed a sleeve-like cover of elastomeric material that envelops a support body and is provided with a plurality of slits that open under the influence of compressed gas. At least one fastening element is provided and has a component that extends at least partially about the aeration element and rests against the upper edge thereof and is spaced from a central portion of the aeration element. The fastening element also has a guide element for securement to a base or carrier member. The guide element has a groove for receiving the lower edge of the aeration element.

Abstract: An apparatus for cleaning ninepins and bowling pins is provided. The apparatus includes a drum-like container that rotates about its longitudinal axis, and that is provided with at least one brush that is disposed in the longitudinal direction of the container. The bristles of the brushes extend perpendicular to the axis of rotation of the container. The container has at least the length of the pin that is to be cleaned, is closed at the bottom, and can, additionally, be filled with cleaning fluid. The length of the bristles of the brush or brushes is adapted to the contour of the pin that is to be cleaned and that does not rotate along with the container.

Abstract: A pin for playing ninepins or for bowling is provided. The base portion of the pin is detachable from the pin body and is replaceable. The base portion comprises a material that is more robust, wear resistant and/or has a higher resistance to scoring than does the remainder of the pin. The base portion can be provided with a reinforcement. The base portion has an annular support surface with at least one radially extending notch, a sharp inner edge, and high static friction to effect an improved ground adhesion.

Abstract: In a method for visually marking bowling pins, a plastic material is blow-molded to form a bowling pin mantle. At least one laser beam is impinged onto the bowling pin mantle and guided in a pattern to create a desired marking by either activating pigments under the mantle skin or making the base color of the bowling pin mantle lighter.

Abstract: A plastic pin having a porous and/or cellular core that is surrounded by a resilient shell is provided. The base of the pin is made of a different material than is the shell. The base is centrally provided with a plug that projects into the core. To improve the connection between the shell and the base, the outer side of the plug is provided with projections that form a positive connection with the core.

Abstract: An elongated apparatus is provided for aerating water, and includes a tubular support body and a sleeve of elastomeric material that surrounds the support body and is provided with slits that open to allow fine bubbles to pass into the water. To achieve a uniform supply of the sleeve with little loss for long apparatus, the inner side of the sleeve is provided with one or more groove-like channels that extend lengthwise relative to the sleeve.

Abstract: An apparatus for aerating water with fine bubbles using elastomeric members having fine openings is provided. The apparatus is provided with one or more lifting bodies in such a way that the apparatus, which is generally disposed at the base of a reservoir or tank, can be raised, by introducing air into the lifting bodies, to such an extent that the apparatus is accessible above the surface of the water.

Abstract: A plastic pin, including a bowling pin, for bowling lanes, and a method of making same, are provided. The pin has a hard shell for surrounding a core of cellular and/or porous polymeric material. The shell defines a hollow interior and in a lower portion of the pin has a bulging portion, thereabove a reduced diameter portion and thereabove an again widening head. A separate insert member is insertable into the hollow interior of the shell into the region of the reduced diameter portion thereof to divide the hollow interior into two hollow chambers. The insert member has a conical outer contour, the smaller diameter end of which faces the head of the pin.

Abstract: A method for manufacturing a plastic bowling pin that has a porous core and a resilient envelope includes the step of blow-forming the envelope in a blowing mold and removing the envelope from the blowing mold. The envelope is then cooled to a temperature of 60.degree. C. to 100.degree. C. A core plastic material containing an exothermic agent is then injected into the envelope for forming the core. The core plastic material is heated to a temperature of 200.degree. C. to 260.degree. C. The inner layer of the envelope is thus fused to the plastic material of the core to provide an intimate connection between the envelope and the core.

Abstract: A roller belt arrangement for a CATERPILLAR (endless track) vehicle has at least one pull resistant belt having a first surface and a second surface opposite the first surface. Drive members are connected to the first surface of the at least one pull resistant belt and extend transversely to a longitudinal extension of the at least one pull-resistant belt. The drive members have a U-shaped foot comprising a stay and two legs, wherein the stay rests on the first surface and the legs project perpendicularly from the first surface. The bolts, having a head and a threaded end opposite the head, are provided for connecting the drive members to the at least one pull-resistant belt. Plate members are non-rotatably positioned between the legs. The bolts penetrate the at least one belt, the stays, and the plate members, with the threaded ends positioned between the legs. Nuts, threaded onto the threaded ends of the bolts, are provided for securing the bolts and are nonrotatably secured relative to the plate members.

Abstract: A roller belt arrangement for a track-type vehicle has pull-resistant belts with a first surface and a second surface opposite the first surface. Drive members are connected to the first surface of the pull-resistant belt so as to extend transverse to a longitudinal extension of the at least one pull-resistant belt. U-shaped members, having a stay and two legs defining a cavity therebetween, are positioned on a second surface opposite the drive members such that the stay rests on the second surface. Cushion members are positioned in the cavity of the U-shaped members. Screw bolts for connecting the drive members to the pull-resistant belt are provided. The screw bolts extend sequentially through the cushion member, the stay of the U-shaped member, the pull-resistant belt, and the drive member. The screw bolts are directly threaded into the drive members.

Abstract: A water aerator is provided that has a rigid support plate that in the operating position is disposed essentially horizontally. The support plate has a practically planar upper surface and at least one aperture for air. An elastic plate of elastomeric material is disposed on the upper surface of the support plate. The elastic plate is provided with a plurality of fine slits that can be widened by air that is introduced between the support plate and the elastic plate. The elastic plate has a rim that sealingly surrounds the downwardly directed rim of the support plate to be secured thereto in a hook-type manner.

Abstract: A plastic pin having a porous and/or cellular core that is surrounded by a hard shell. To be able to influence the level of the center of gravity of the pin, the shell is provided with an aperture in which is secured an insert in the form of a hollow body that extends into the interior of the shell and is disposed coaxially thereto. The hollow body can extend from the head of the pin beyond the neck and into the upper portion of the barrel portion of the pin.

Abstract: A plastic pin, such as a bowling pin, for bowling lanes. The pin has a hard shell that surrounds a core of cellular and/or porous material, preferably a thermoplastic material. The interior of the shell has at least one partition that divides the hollow interior of the shell.

Abstract: A plastic pin, including a bowling pin, for bowling lanes, and a method of making the same. The pin has a hard shell that surrounds a core of cellular and/or porous material. The shell has a lower bulging portion, thereabove a neck-like reduced diameter portion and thereabove an again slightly wider head. The shell has a wall thickness that from the greatest diameter part of the bulging portion increases gradually both upwardly toward the reduced diameter portion and downwardly toward a base of the pin. The plastic for the core of the pin is introduced into the hollow interior of the shell and fills at least a portion thereof by expansion. The core plastic is introduced at such a temperature that an inner surface of the plastic shell is softened at least at some locations by contact with the introduced core plastic to thereby effect fusion between the plastic of the shell and the introduced core plastic.