DUAL DENSITY MOLDED MEMBER, TOOLING AND METHOD THEREFOR

A dual density molded member, a dual density molded tooling, and a method of forming the dual density molded member, the dual density molded member including an outer shell comprising a self-skinning polyurethane foam, and a core comprising a urethane foam, the self-skinning polyurethane foam being higher in density than the urethane foam

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

The disclosure relates in general to a molded member, and more particularly, to a dual density molded member, tooling, and method therefor.

2. Background Art

Molding typically consists of shaping a liquid or pliable raw material via rigid frame called a mold. The mold is a hollowed-out block that is filled with the liquid or pliable material, e.g., plastic, glass, metal, or ceramic raw material. The liquid sets or hardens inside the mold, adopting its shape. There are various types of molding including articulated molding, piece-molding, blow molding. A release agent is typically used to ease removal of a molded product from the mold. Molding can be used to make furniture, structural materials, household goods, cases, or any other product that can be manufactured via molding.

DETAILED DESCRIPTION OF THE DISCLOSURE

While this disclosure is susceptible of embodiment in many different forms, there is shown in the drawings and described herein in detail a specific embodiment(s) with the understanding that the present disclosure is to be considered as an exemplification and is not intended to be limited to the embodiment(s) illustrated.

Referring now to the drawings and in particular toFIGS.1-4, a dual density molded tooling apparatus, such as dual density molded tooling100, used to manufacture a dual density molded member apparatus, such as dual density molded member200, are illustrated. The dual density molded tooling100includes a base block110. The base block110includes a contoured inside surface111and a non-contoured outside surface112. The contoured inside surface111of the base block110is contoured to correspond to an outside surface201of the dual density molded member200. Although the outside surface112of the molded tooling100can be otherwise configuration, in this example the outside surface112of the molded tooling100is rectangular in shape, with sides other than the contoured inside surface111being planar and being perpendicular to each other.

In at least one configuration, the base block110can further include first and second guide rod openings113,114disposed on either side of the contoured inside surface111, extending substantially parallel to first and second sides110c,110dof the base block110. The first and second guide rod openings113,114can extend from a first end110aof the base block110to a second end110bof the base block110. The first and second guide rod openings113,114accept first and second guide rods115,116, respectively. The first and second guide rods115,116are coupled to a foam core mount cap140, and can be vertically oriented during use as shown inFIGS.5and6.

Disposed between the foam core mount cap140and a foam core substrate130used to form the dual density molded member200is a skin cap plate160. The skin cap plate160includes first and second openings to allow the first and second guide rods115,116to slide through these first and second openings. In this configuration, the first and second guide rods115,116, the foam core mount cap140, and the foam core substrate130move as a single unit. The first and second guide rods115,116enter the first and second guide rod openings113,114to align the foam core substrate130as it enters a first inner cavity117formed when a base-side cap120is coupled to a side of the base block110facing the contoured inside surface111. With the base-side cap120and the base block110so coupled, foam will not escape from the first inner cavity117during manufacture of the dual density molded member200. In at least one configuration, first and second male plugs171,172can be disposed through openings through the base block110and the base-side cap120. The first and second male plugs171,172allow molding fluid to enter the first inner cavity117.

In at least one configuration, first and second guide rod extensions148,149can be coupled to the foam core mount cap140on an outside surface thereof facing away from the foam core substrate130. The first and second guide rod extensions148,149correspond to the first and second guide rod openings113,114and the first and second guide rods115,116. Substantially centrally on this same outside surface of the foam core mount cap140is shown a foam twist plug147that extends through an opening in foam core mount cap140to allow checking of an amount of foam fluid within the first inner cavity117during manufacture of the dual density molded member200, the foam twist plug147being lockable against the forma core mount cap140via locking members, as shown.

The foam core substrate130is shaped to follow a contour of the contoured inside surface111and the planar surface on the front of the base-side cap120. When the foam core substrate130is disposed within the first inner cavity117formed when a base-side cap120is coupled to a side of the base block110, as discussed above, a second inner cavity217(FIG.4) is formed within the dual density molded member200during molding of the dual density molded member200. The foam core substrate130is shorter in length than a length of the contoured inside surface111of the base block110, such that when the foam core substrate130is disposed within first inner cavity117formed by the contoured inside surface111there is space for foam to cover a distal end130aof the foam core substrate130.

In the configuration shown, the base-side cap120is rectangular in shape, and planar on front and back sides thereof. This planar surface on a front surface of the base-side cap120produces a flat surface on a back of the dual density molded member200. In at least one other configuration, the base-side cap120can be contoured, at least similar to the contoured inside surface111, depending upon a desire shape for the dual density molded member200. In at least one configuration, a text insert block150can be coupled (e.g., bolted) to the contoured inside surface111of the base block110such that when the dual density molded member200is being molded within the dual density molded tooling100text151can be imprinted onto a surface of the dual density molded member200, as shown. In at least one configuration, first and second stabilizer feet161,162can be coupled (e.g., bolted) to the base block110at the second end110bthereof, that is on an opposite end of the back block110showing the first and second guide rod openings113,114.

In the example of the dual density molded member200disclosed herein shown in more detail inFIG.4, the dual density molded member200can include tapered sides401on both sides of the dual density molded member200, as shown. The dual density molded member200can include a flat bottom surface402and a curved top surface403. In at least one configuration, the dual density molded member200can include a plate410(e.g., metallic plate) that provides rigidity and provides a mounting point for the dual density molded member200. The plate410can be molded into the dual density molded member200. The plate410can include various openings411disposed through the plate410, the openings411can be used for mounting the plate410. One skilled in the art would understand that the shape of the dual density molded member200is just an example, and that dual density molded member200can take on an unlimited number of shapes.

During use of the dual density molded tooling100to manufacture the dual density molded member200by an operator501, a system500includes the foam core cap140coupled to a horizontal frame member510of a frame505that supports the foam core cap140, the skin cap plate160, and the foam core substrate130, with the foam core substrate130pointing in a downward direction, as shown inFIGS.5and6. The foam core cap140, the skin cap plate160, and the foam core substrate130move vertically up and down during manufacture of the dual density molded member200. Then, the base-side cap120is coupled to a side of the base block110, thereby forming the first inner cavity117. An actuator (not shown) then moves the foam core cap140, the skin cap plate160, and the foam core substrate130downward until tops of the base block110and base-side cap120come to rest against a bottom of the skin cap plate160. A higher density self-skinning polyurethane foam450(FIG.4) is injected into the first inner cavity117, the self-skinning polyurethane foam450flowing around the foam core substrate130thereby forming a shell.

Once the self-skinning polyurethane foam450is at least partially cured, the actuator lowers the coupled base-side cap120and base block110, thereby exposing the dual density molded member200. At this point, the dual density molded member200includes the second inner cavity217. A lower density urethane foam460(FIG.4) is then poured into the second inner cavity217as a core for the dual density molded member200, that is lower in density than the self-skinning polyurethane450shell. Once the lower density urethane is cured, another mold cover (not shown) similar to the skin cap plate160is coupled to the coupled base-side cap120and base block110. Additional higher density self-skinning polyurethane is then injected over the filled dual density molded member200to cover and seal the lower density urethane foam460now disposed within the second inner cavity217. This other mold cover is then removed, and the base-side cap120is decoupled from the base block110, allowing the filled dual density molded member200to be removed from the base block110by the operator501.

Such a configuration as described above for the dual density molded member200allows the dual density molded member200to be used as a cushion that can withstand rain, such as within a system700that includes an upstanding lawn mower720and the dual density molded member200(FIG.7). As an outer portion of the dual density molded member200includes the higher density self-skinning polyurethane foam450, this results in the dual density molded member200being water resistant. As an inner portion of the dual density molded member200includes the lower density lower density urethane foam460, the dual density molded member200is also more compliant as compared to use of a single higher density cushion, the dual density molded member200providing comfort to an operator710of the upstanding lawn mower720. Thus, the dual density molded member200therefore includes the higher density self-skinning polyurethane foam450as a shell over the lower density urethane foam460, this combination providing both water resistance and comfort. Typical cushions for an upstanding lawn mower include a single type of foam covered with a vinyl material. The dual density molded member200is additionally more economical to produce that such a typical vinyl covered foam cushion.

The foregoing description merely explains and illustrates the disclosure and the disclosure is not limited thereto except insofar as the appended claims are so limited, as those skilled in the art who have the disclosure before them will be able to make modifications without departing from the scope of the disclosure.