Abstract: A linear compressor includes one spring assembly including a plurality of spring parts fixed to both side surfaces of a supporter and a rear cover and configured to support a load generated in the compressor. In addition, both side portions of the spring part are provided with fixing brackets coupled to the supporter and the rear cover, and the fixing bracket is provided with an insertion member or a bracket coupling member so that the coupling force of the spring part can be increased.

Abstract: An actuator is provided for raising the front hood of a vehicle having at least one extension part, by whose extension movement the front hood of the vehicle can be raised or is raised. It is provided that the extension part is at least partially formed by a planar formation, which is deformable from a first shape (e.g., a starting shape) into a second shape (e.g., an intermediate shape or final shape) to raise the front hood. Furthermore, a motor vehicle is provided that has an actuator for raising the vehicle front hood and a pedestrian protection system for a vehicle.

Abstract: An internal combustion engine having: a crankshaft; camshafts that activate intake and exhaust valves; an auxiliary shaft, which rotates in an opposite direction with respect to the crankshaft and is unbalanced so as to act as balancing countershaft; and a mechanical transmission, which receives the movement from the crankshaft and controls the timing by causing the rotation of the camshafts and, at the same time, causes the rotation of the auxiliary shaft.

Abstract: A device for a hydraulic rock drilling machine (1) for the protection of a piston seal unit (6) for sealing between a percussive piston (4) and a cylinder in a housing (2) of the rock drilling machine, wherein a piston guide (5) is positioned between the piston seal unit (6) and a working space in the cylinder. Between the piston guide (5) and the piston seal unit (6) there is arranged a surrounding ring-shaped inwardly open chamber (9), which is formed for receiving a hydraulic liquid volume. A hydraulic supply flow channel (12,13) for hydraulic liquid supply is connected to said chamber (9). The invention also concerns a rock drilling machine and a method.

Abstract: The various embodiments herein provide a coaxial hydraulic actuator assembly for an aircraft hydraulic system for providing the dual redundancy operations in normal and emergency operations. The embodiments herein adopt a coaxial hydraulic cylinder based actuator system comprising a conventional fixed cylinder with a moving piston actuator. The fixed cylinder with a moving piston actuator is located in a first region. The fixed cylinder with the moving piston actuator is manufactured in tandem with a moving cylinder with fixed piston actuator. The moving cylinder with a fixed piston actuator is located in a second region. The fixed piston actuator in the second region is also referred to as actuation rod. Further, the coaxial hydraulic cylinder based actuator system comprises a first adapter and a first cap for the first region. Similarly, a second adapter and a second cap are provided for the second region.

Abstract: An assembly includes an actuator assembly having a housing, a piston positioned at least partially within the housing and movable relative to the housing for an overall actuation stroke, a first spring operatively engaged between the piston and the housing to provide actuation biasing force therebetween, a second spring operatively engaged with the piston, and a spring guide. The spring guide is operatively engaged with the first spring and operatively engaged with the piston via a sliding connection. The spring guide is further configured to limit a stroke of the first spring such that the first spring contributes actuation biasing force between the piston and the housing for only a fractional portion of the overall actuation stroke of the piston.

Abstract: A soft composite actuator is described, including a first elastomeric layer; a strain limiting layer; and a first radially constraining layer, wherein the first elastomeric layer is disposed between the first radially constraining layer and the strain limiting layer; and the elastomeric layer, the strain limiting layer, and the radially constraining layer are bonded together to form at least one bladder for holding pressurized fluid. Methods of using and making of the soft composite actuator are described.

Abstract: Soft pneumatic actuators based on composites consisting of elastomers with embedded sheet or fiber structures (e.g., paper or fabric) that are flexible but not extensible are described. On pneumatic inflation, these actuators move anisotropically, based on the motions accessible by their composite structures. They are inexpensive, simple to fabricate, light in weight, and easy to actuate. This class of structure is versatile: the same principles of design lead to actuators that respond to pressurization with a wide range of motions (bending, extension, contraction, twisting, and others). Paper, when used to introduce anisotropy into elastomers, can be readily folded into three-dimensional structures following the principles of origami; these folded structures increase the stiffness and anisotropy of the elastomeric actuators, while keeping them light in weight.

Abstract: The invention relates to a piston accumulator (1) and a method for determining a position of a piston (5) that can be moved inside a housing (3) of the piston accumulator (1). One or more inductive sensors (15) are arranged on an exterior surface (21) of the housing (3) and configured to detect a movement of the piston (5) inside the housing (3) caused by electromagnetic induction. In this way, a determination of the current position of the piston (5), which is technically simple to realise and contact-free, can be implemented and used, for example, to monitor a charge state of the piston pressure accumulator (1).

Abstract: In a spring piston airgun, a compression piston is provided for longitudinal translation within a compression tube in response to a motive force. The compression piston includes a main piston body and a piston head, wherein the piston body and piston head are coupled for partial independent translation along a longitudinal axis. A resilient compressible bushing is longitudinally intermediate a portion of the piston body and the piston head, such that upon a deceleration of the piston head, the piston body is not immediately acted upon by the deceleration, rather the bushing absorbs a portion of the deceleration and radially expands to contact the compression tube.

Abstract: A piston for a pump includes a hub portion defining opposing outer surfaces and concave lateral portions between the opposing outer surfaces. The piston also includes inserts configured to provide a replaceable surface, the inserts being coupled to each of the opposing outer surfaces. A pump includes a housing having an inlet and an outlet, and at least two pistons having a hub portion and inserts. The pump may be a positive-displacement, rotary pump, and the pistons may be circumferential pistons.

Abstract: A brake actuator is provided, in which a diaphragm, used in conjunction with a piston which compresses a parking brake-actuating spring, is arranged such that its outer peripheral region is captured between opposing housing flange portions such that a seal between the interior and exterior of the brake actuator housing is provided in a radially-oriented region of the diaphragm and the housing flange portions away from housing portion jointing components such as a clamp ring or individual fasteners. The diaphragm may also be provided with a wedge-shaped portion at its outer periphery which is axially oriented and configured to reside in a corresponding annular gap between the opposing housing flange portions.

Abstract: A cylinder has an insulating gas boundary layer (IGBL) across the cylinder wall inner surface, the IGBL formed by injection of an insulator fluid into the combustion chamber of the cylinder. In one implementation, a pressure differential is engineered between the top region of the cylinder and the bottom region of the cylinder. In yet another implementation, the insulator injection pressure is temporally modified in synchronicity with the piston cycle and/or in accordance with other temporal factors to provide appropriate IGBL coverage.

Abstract: A sealing system for use in a rotary vane actuator having a stator and a rotor coupled to the stator. The rotor or the stator has a vane. The rotor or the stator has a groove within which the seal is positioned. The stator, the rotor and the seal coact to define a chamber. The vane being movable thereby altering a volume of the chamber, with the seal being continuous.

Abstract: Methods, apparatuses, and systems for circumferential sealing of piston assembly in a piston actuator. A piston assembly for a piston actuator includes a piston including an extending surface, a retracting surface, and a circumferential surface that connects the extending surface and the retracting surface. The piston is adapted to engage and seal against an interior surface of a cylinder bore of an actuator. The piston assembly includes a first unidirectional passage connecting the extending surface and the circumferential surface.

Abstract: A piston seal includes an inner surface configured to extend proximate a perimeter of a piston. Also included is an outer surface disposed proximate a chamber wall, wherein the chamber wall defines a chamber for the piston and the piston seal to translate within. Further included is a first axial side exposed to a first pressure portion of the chamber. Yet further included is a second axial side exposed to a second pressure portion of the chamber. Also included is at least one pressure differential reducing hole extending radially through the piston seal from the inner surface to the outer surface.

Abstract: A rotary actuator includes a housing defining a first arcuate chamber comprising a cavity, a fluid port in fluid communication with the cavity, and an open end. A rotor assembly in the housing includes an output shaft and a rotor arm extending radially outward from the output shaft. An arcuate-shaped piston is disposed in the housing for movement in the arcuate chamber. The rotary actuator includes a fluid line is coupled to the fluid port, a high pressure fluid line, a low pressure fluid line, and a central pressure source coupled to the high pressure fluid line. A servo valve is positioned between the central pressure source and the hydraulic actuator and is controllable to selectively connect the fluid line to the high pressure fluid line and the low pressure fluid line to control movement of the hydraulic actuator.

Abstract: A rotary actuator includes a housing defining an arcuate chamber including a cavity, a fluid port in fluid communication with the cavity, and an open end. A rotor assembly includes an output shaft and a rotor arm extending outward. An arcuate-shaped piston is disposed in said housing for reciprocal movement in the arcuate chamber through the open end, wherein a seal, the cavity, and the piston define a pressure chamber, and a portion of the piston contacts the first rotor arm. A central actuation assembly includes a central mounting point formed in an external surface of the output shaft, said central mounting point proximal to the longitudinal midpoint of the shaft, and an actuation arm removably attached at a proximal end to the central mounting point, said actuation arm adapted at a distal end for attachment to an external mounting feature of a member to be actuated.

Abstract: A rotary actuator includes a first housing defining a first arcuate chamber having a first cavity, a first fluid port in fluid communication with the first cavity, and an open end. A rotor assembly is rotatably journaled in the first housing and having a rotary output shaft and a first rotor arm extending radially outward from the rotary output shaft. An arcuate-shaped first piston is disposed in the first housing for reciprocal movement in the first arcuate chamber through the open end, wherein a first seal, the first cavity, and the first piston define a first pressure chamber, and a first portion of the first piston contacts the first rotor arm.

Abstract: A rotary actuator includes a housing, a rotor assembly rotatably journaled in said housing and including a rotary output shaft, a central actuation assembly including a central mounting point formed in an external surface of the rotary output shaft, said central mounting point proximal to the longitudinal midpoint of the rotary output shaft, a mounting assembly adapted for attachment to an external mounting connector of a mounting surface of an aircraft structural member, and an actuation arm removably attached at a proximal end to the central mounting point, said actuation arm adapted at a distal end for attachment to an external mounting feature of an aircraft assembly to be actuated.

Abstract: A rotary actuator includes a piston housing assembly including a cavity, a fluid port in cavity, and an open end. A rotor assembly is rotatably journaled in the piston housing assembly and includes a rotary output shaft, a rotor arm extending radially outward from the rotary output shaft, an arcuate-shaped piston disposed in said piston housing assembly for reciprocal movement in the piston housing assembly through the open end along a radius of curvature. A seal, the cavity, and the piston define a pressure chamber, and a portion of the piston connects to the rotor arm at an end portion.

Abstract: A rotary actuator includes a housing, a first piston housing assembly comprising a first cavity and an open end, a rotor assembly rotatably journaled in said housing and comprising a rotary output shaft and a first rotor arm extending radially outward from the rotary output shaft to a first distal end comprising one or more first retainers, and an arcuate-shaped first piston disposed in said housing for reciprocal movement in the first piston housing assembly through the open end along a radius of curvature. A first portion of the first piston connects to the first rotor arm at a first end portion comprising one or more second retainers. The first retainers and the second retainers are intermeshed along the radius of curvature such that movement of the rotor assembly urges movement of the first piston and movement of the first piston urges movement of the rotor assembly.

Abstract: A rocking cylinder assembly comprising a cylinder, rotatable about a rocking axis between first and second end positions, having a cylinder bore terminating at a cylinder bearing surface and a cylinder aperture, and a bearing component having a component bore terminating at a component bearing surface and a component aperture. The ratio of the area of the second one of the apertures to the square of the maximum extent of the second one of the apertures in a direction perpendicular to the rocking axis and perpendicular to a second axis for fluid flow is greater than the ratio of the area of the first one of the apertures to the square of the maximum extent of the first one of the apertures in a direction perpendicular to the rocking axis and perpendicular to a first axis for fluid flow.

Abstract: A method of locking a linear output member in a retracted position within a linear actuator, where the linear output member is capable of axial motion within a housing of the linear actuator, includes rotating a generally tubular rotor disposed within a rotary lock assembly of the actuator to a first rotor position, and shifting a lock capable of radial displacement within the rotary lock assembly based on rotating the rotor to the first position. The lock engages a radial groove of the linear output member when the linear output member is in a retracted position. The rotary lock assembly is constrained from axial motion. The radial groove of the linear output member includes an axially angled, substantially planar surface. The lock is configured to include an axially angled surface shaped complimentary to the axially angled, substantially planar surface of the radial groove.

Abstract: A cylinder accumulator system is disclosed. The system includes a cylinder comprising a cylinder rod, a cylinder barrel coaxial to the cylinder rod, a cylinder end cap coupled to the cylinder barrel and the cylinder rod, and a cylinder piston assembly disposed within the cylinder barrel. The cylinder piston assembly further includes a dynamic sealing arrangement, which comprises one or more dynamic seals. The system further includes a first annular volume coaxial to the cylinder rod and the cylinder barrel, and a second volume disposed within the cylinder piston assembly. The system also includes a piston disposed within a bore of the second volume and between a hydraulic fluid located on a first side of the piston and a gas media located on a second side of the piston. The system also includes an external high-pressure accumulator, a low-pressure accumulator, and one or more tube manifolds coupling the external high-pressure accumulator and low-pressure accumulator to the cylinder.

Abstract: A pneumatic pressure brake booster system includes an air pressure chamber; an ambient air chamber; a flexible diaphragm separating the air pressure chamber and the ambient air chamber; at least one air pressure source communicating with the air pressure chamber; a brake pedal shaft engaged by and movable with the diaphragm; and a brake master cylinder engaged by the brake pedal shaft.

Abstract: The disclosure relates to a method for operating a positioning actuator system with an electronically commutated actuator drive for driving an actuator element, having the following steps: non-volatile storage of a position information item of the actuator element or of a rotor of the actuator drive which was detected last as a reference position before the positioning actuator system is switched off; in the case of switching on of the positioning actuator system retrieval of the reference position and actuation of the actuator drive by energizing the actuator drive in accordance with a space phasor which is dependent on the reference position. The object is to make available an improved method for releasing blockage of an actuator element or actuation after activation of a motor system with a maximum actuating torque. For positioning actuators with commutated motors such as, for example, synchronous motors.

Abstract: Method for manufacturing a crankcase of a piston compressor, wherein the piston compressor is provided with a crankcase which is provided with recesses for therein receiving cylinders and with at least an inlet opening, wherein from a flat sheet at least one substantially rectangular body blank is manufactured provided with the desired cylinder receiving recesses, wherein the body blank is then angle bent in an angle bending machine for forming a body part having a limited number of folds, wherein at least two substantially flat end walls are manufactured from a flat sheet, wherein thereupon the at least one body part and the at least two end walls are positioned with respect to each other using a positioning tool and are connected with each other with a welding robot for forming the crankcase. Also disclosed is a crankcase obtained with the method, and a piston compressor provided with such a crankcase.

Abstract: Pistons and methods of making the same are disclosed. An exemplary piston assembly may include a piston crown and skirt. The crown may include a crown collar wall extending downward toward a free end of the crown collar wall. The skirt may include a pair of oppositely disposed pin bosses that each define piston pin bores configured to receive a piston pin for securing a connecting rod between the pin bosses. The skirt may further include a radially inner skirt mating surface abutted along a radially inner interface region with the radially inner crown mating surface, and a radially outer skirt mating surface abutted along a radially outer interface region with the radially outer crown mating surface such that a cooling gallery is substantially enclosed. The skirt may further include an inner collar wall extending upwards to the free end of the crown collar wall.

Abstract: A device for applying a directed contact pressure force to a multitude of samples. A first part of the device includes a multitude of sample receptacles that receive a multitude of joining surface modules of the same kind, and a second part of the device is connected to the first part in such a manner that a multitude of fluidically intercommunicating hydraulic cylinders in one of the two parts can load the joining surface modules simultaneously in a loading direction at a predetermined force that is substantially identical in respect to all samples.

Abstract: A secure corset is applied in particular to the immobilization in the maximum opening position of an aircraft landing gear cage hatch. The corset has two half-shells that are able to enclose the piston of the actuator having an axis coincident with the common longitudinal axis of the half-shells once they are closed around the piston. Locking pins are able to hold the half-shells around the actuator. The corset also has a casing secured to at least one of the half-shells and equipped with a hooking unit that is able to be coupled to a fixed point on the structure. A structure for varying the distance between the casing and the hooking unit are able to move the hooking unit away from or towards the corset along the common longitudinal axis of the half-shells.

Abstract: A fluid cylinder assembly including a cylinder, a rod assembly, and a valve assembly. The rod assembly includes a rod having a first end and a second end and a piston connected to the first end of the rod. The piston is slidingly positioned in the cylinder. The second end of the rod extending from the cylinder. The valve assembly is in fluid communication with the cylinder. The valve assembly is configured to moderate pressure within the cylinder when an external force is applied against the second end of the rod.

Abstract: In various embodiments, dead space and associated coupling losses are reduced in energy storage and recovery systems employing compressed air.

Abstract: Apparatus for the generation of pressure waves for seismic surveys in marine environment comprising a cylinder (3), defining an axis, in which a striker piston (1) and a pump piston (2) are situated, each having two respective opposite sides with respect to said axis, of which a side of the striker piston (1) situated in front of the pump piston (2) is defined first impact side, and a side of the pump piston (2) in front of the striker piston (1) is defined second impact side, the pump piston (2) and the striker piston (1) sliding in the cylinder (3) in a direction parallel to the axis, and the pump piston (2) and striker piston (1) being such as to strike against each other, by means of the first and the second impact sides, the striker piston (1) being driven by activation means pressing on the side opposite to its own impact side, wherein the cylinder (3) comprises, at one of its ends, a chamber (15) having a diameter larger, smaller or equal to that of the portion of cylinder (3) in which the striker pist

Abstract: A coupling apparatus has an input piston disposable on a braking input element and an output piston disposable on a brake master cylinder, to which a driver braking force is transferable via the input piston. In a first operating mode, the input piston displaced out of its initial position over a brake application distance less than a first minimum brake application distance, is spaced apart from the output piston. In a second operating mode, the input piston displaced out of its initial position over a brake application distance less than a second minimum brake application distance, is spaced apart from the output piston, and the driver braking force is transferable via the input piston to the output piston.

Abstract: A control device for a reservoir charging pump of a braking system of a vehicle includes: an actuating device designed to actuate the reservoir charging pump into at least one normal mode having a normal rotational speed, and a receiving device designed to receive a variable provided by a vehicle-specific component with respect to a supply voltage provided to the reservoir charging pump. The actuating device is additionally designed to ascertain whether the variable received lies outside a normal value range that is specified for the normal mode, and, if necessary, to actuate the reservoir charging pump from the normal mode into at least one deviation mode having at least one setpoint rotational speed deviating from the normal rotational speed.

Abstract: Handles, extendable handles, and linkage mechanisms are examples of apparatuses that include a body; a pivotably attached head; cylinder, actuator, or hydraulic actuator; a fluid passage or hose; and a valve, blocking means, or hydraulic control device. The valve, blocking means, or hydraulic control device may be normally open and may close only when held closed, and may be connected on one side to the fluid passage or hose and on another side to atmosphere. An operator may use a tool, such as a drywall flat box attached to the head, by holding the handle and controlling pivoting of the head by operating the valve. Methods include providing for an operator to control a tool on a handle, and include providing the handle and instructing the operator to actuate the blocking means to hold the tool in a constant orientation relative to the handle.

Abstract: The present invention provides a linear compressor, including: a cylinder having a compression space of refrigerant therein; a piston linearly reciprocated inside the cylinder to compress the refrigerant; a supporter connected to the back of the piston; a plurality of front and rear main springs for elastically supporting the supporter; a motor cover installed at the front of the supporter with a predetermined interval in an axis direction to support the front main springs, a pair of supporting ends being formed by partially cutting an inner portion of the motor cover and bent backward; and a rear cover installed at the back of the supporter with a predetermined interval in an axis direction to support the rear main springs, and fixedly welded to the supporting ends of the motor cover. Unnecessary parts of the motor cover can be welded to the rear cover to prevent a material loss, and a mass-production process can be simplified to improve productivity.

Abstract: A single acting hydraulic cylinder apparatus includes a mechanism operated by a single acting hydraulic cylinder, the mechanism including a hollow member. A breathing chamber is provided by sealing at least a portion of the hollow member such that outside air is prevented from entering the breathing chamber. A pressurized port of the hydraulic cylinder is adapted for connection to a pressurized hydraulic fluid source, and an un-pressurized breathing port of the hydraulic cylinder is connected to the breathing chamber such that air can flow between the breathing port and the breathing chamber.

Abstract: There is disclosed a radial piston machine comprising a cylinder block having at least one bore in which a piston supported on an eccentric disk is movably guided via roll bodies, wherein at least one hydrostatic relieving field is provided between the piston and the roll body. According to the invention, the active surface A2 of the relieving field is equal to or larger than the active piston area A1 of the piston restricting a cylinder chamber and the relieving field is in fluid communication with the cylinder chamber via a hydraulic resistance.

Abstract: A two-stroke internal combustion engine including a molded ignition housing connected to the crankcase of the engine which protects the electric generator of two-stroke internal combustion engine.

Abstract: A cylinder-crankcase is disclosed that includes a cylinder block having a cylinder head for receiving a spark plug. The cylinder-crankcase also includes a crankcase and a crank arm for supporting a crankshaft. The cylinder block, cylinder head, crankcase and crank arm are a single, monolithic piece.

Abstract: A reciprocating pump (10) for pumping seawater or other fluid under high-pressure. The pump (10) has a pump body (11) defining an internal space (13) and an opening (18) onto the internal space. A plunger (25) extends through the opening (18) and into the internal space (13). A sheath (30) closes the opening (18) and embraces an inner portion of the plunger (25), whereby pumping chamber (33) is defined between the pump body (11) and the sheath (30). The sheath (30) is deformable in response to reciprocatory movement of the plunger (25) to effect volume change within the pumping chamber (33). The sheath (30) comprises a first portion (31) which is generally stable, and a second portion (32) which embraces the plunger (25) and which deforms through expansion and contraction upon reciprocatory movement of the plunger. The first portion (31) defines a mounting flange (35) clampingly engaged with the pump body (11). The sheath (30) incorporates a recess (45) adjacent the open end thereof.

Abstract: A dual end stop is provided for setting precise open and closed positions for the valve to which the pneumatic actuator is attached. In a preferred embodiment, a stop assembly housing contains two stop adjustment bolts as well as a cam that defines first and second stop surfaces. The stop assembly housing is preferably mounted to the actuator housing outside of the pressurized zone contained by the actuator housing. The stop bolts and associated threaded apertures are designed for minimum overhang of the stop bolts to provide more support. The stop assembly housing not only preferably houses the stop assembly components but also preferably serves as an adaptor plate for the various valves to which the actuator may be mounted. The stop bolts preferably have a convex head to provide a defined point contact rather than a random point contact as may be produced with flat heads.

Abstract: An apparatus includes a motor with an output shaft. A solitary air compressor is linked to the output shaft so as to be driven by the output shaft. The compressor contains a piston in a cylinder. A first fan is mounted on the output shaft to direct cooling air to the motor. A second fan is mounted on the output shaft to direct cooling air to the compressor.

Abstract: A damper comprises a first chamber and a second chamber separated by a piston. At least one of the chambers includes an axially moveable member and an axially fixed member. A resilient or compressible member is positioned between the axially moveable member and the axially fixed member. The axially moveable member is displaced toward the fixed member during slight pressure increases to absorb small pressure fluctuations that may be insufficient to cause flow through the piston.

Abstract: A piston for the variable delimitation of a pressure chamber in a housing of a hydraulic cylinder, in particular a clutch master cylinder for motor vehicles, has a main section on which a running surface is provided for a sealing element on the housing side. The sealing element seals a pressure chamber in an operating position of the piston. The piston also has an after-running device, which, in a normal position of the piston, connects the pressure chamber to an after-running area. The after-running device is made separately from the main section and is connected without play to the main section to form the piston. As a result, a piston that is easy to manufacture is created and which, with reference to the after-running device, has an improved functionality compared with prior art.

Abstract: In a crankcase for a piston machine having a bearing support structure for a crankshaft main bearing with a bearing base part integrally formed with the bearing support structure and a bearing cover mounted onto the bearing base part by bearing bolts extending into bolt mounting columns, the bearing support structure includes a transverse wall which extends between the crankcase walls, the bearing support base and the bearing base part and includes a rib structure of an increased wall thickness formed between the bearing base part and the bearing support base and having a recess in the area between the end of a mounting bolt bore in the bolt mounting column and the bearing support base providing for a force flux path which istributes the force flux evenly over the length of the threaded mounting bolt bore area.

Abstract: Methods of using styrene oil, its fractions, and combinations thereof as working fluids, lubricants, fuels and solvents.

Abstract: A pump diaphragm that is composed of two different shore-hardness materials of the same base polymer. The diaphragm includes a strong layer that will withstand hydraulic pressures and one or more soft layers that can be shaped into desirable sealing configurations. The diaphragm is constructed by first injecting a first thermoplastic material, with a relatively lower percentage of rubber filler, into a mold cavity and allowing the first material to cure. The hardened first material is then placed into a second mold cavity. A second thermoplastic material which contains the same base polymer but a relatively higher percentage of rubber filler is then injected into the second cavity. The first and second material utilize the same base polymer and thus will have the same melt temperature, as well as a strong propensity to bond to each other when molten. The second material is introduced to the cavity at a temperature that melts the interface of the first material.