BRIEF DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which:
FIG. 1 is a perspective view of the injection molding station;
FIG. 2 is a configuration drawing showing the “first-shot” formation of the first component through the use of a central core pin and transverse core pin that defines the central bore and the socket, respectively;
FIG. 3 is an exploded drawing showing the first component being transferred by the core pin to a “second-shot” mold having a fluid-cooled central core pin that seals off the blind hole formed in the socket during the first shot; and
FIG. 4 is a cross-sectional view of the second mold showing the fluid-cooled core pin sealing off the blind hole formed in the socket during the first shot to prevent it from being filled during the second shot.
Similar reference characters refer to similar parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, the injection molding manufacturing apparatus and method of the invention is employed through the use of a molding station 10 having a first shot mold 12 and a second shot mold 14 with conventional drive mechanism 16 and transfer mechanism 18. The molding station 10 allows for the injection molding of a “first shot” cylindrical component 20 with a longitudinal bore having a depending skirt 22 with a transverse socket 24 having a blind hole 26 therein.
More particularly, as best shown in FIG. 2, the first shot mold 12 comprises a interior configuration that defines the outer configuration of the component 20 to be injection molded. The component's 20 longitudinal bore is defined by a conventional core pin 28 having the desired configuration for the bore. The blind hole 26 is formed within the socket 24 by means of a transverse core pin 30 which is inserted through the central core pin 28 after the central core pin 28 is moved into position. The first component 20 may comprise a cylindrical sleeve used during the construction of a heat sealable inflator, such as that described in our concurrently-filed patent application entitled “Heat Sealable Inflator”, the disclosure of which is hereby incorporated by reference herein.
Referring now to FIG. 3, after the first component 20 is shot in the first mold 12, it is transferred by means of the transfer mechanism 18 to the second mold 14 by means of the transfer core pin 28. The second shot mold 14 includes an interior configuration that defines the outer configuration of the second component 32 to be produced, such as the inflator more particularly disclosed in our concurrently-filed application (see FIG. 4). Specifically, the second-shot component 32 may include a central passageway defined by a central core pin 34 positioned within the first component 20 by means of the drive mechanism 16. Importantly, the central core pin 34 may comprise a fluid-cooled core pin to maintain the core pin at a predetermined temperature to minimize expansion or contraction thereof that would otherwise alter the manufacturing tolerances during the second-shot molding operation. As best shown in FIG. 4, the core pin 34 includes an outer configuration that moves into adjacent contact with the upper edge of the blind hole 26 formed in the socket 24 of the skirt 22 of the first component 20 such that the blind hole 26 is blocked-off to prevent any injection material from flowing therein during the second shot. It is noted that a transverse core pin 36 may be employed to form a through hole 38 through the other side of the second component 32 in alignment with the blind hole 26 of the socket 24.
It should be appreciated that due to the fluid-cooled core pin 34, the transverse core pin 36 could not extend therethrough to form the blind hole 24 else the cooling fluid would leak from the core pin 34. It should therefore be appreciated that the use of the socket 24 with its blind hole 26 achieves an important advantage over prior art molding processes since it allows the formation of a central bore with extremely high tolerances.
Finally, it should be appreciated that while the molding station 10 discussed above contemplates two-shot molding steps, the first component 20 may be manually transferred from the first shot mold 12 to a second shot molt 14 without the use of the transfer mechanism 18.
The present disclosure includes that contained in the appended claims, as well as that of the foregoing description. Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention.
Now that the invention has been described,
Patent Application
20070269636
