BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the exemplary embodiments of the present invention (including alternatives and/or variations thereof) may be obtained with reference to the detailed description of the exemplary embodiments along with the following drawings, in which:
FIG. 1 is a is a top elevation view of a known injection molding system;
FIG. 2 is a schematic of a known pneumatic structure connected to empty holders of a multi-stage post-mold device;
FIG. 3 is a schematic of a pneumatic structure in accordance with an exemplary embodiment of the present invention connected to empty holders of a multi-stage post-mold device, prior to a startup thereof;
FIG. 4 is a schematic of the pneumatic structure of FIG. 3 as configured to connect the empty holders of the multi-stage post-mold device to a pressure source, during start-up operation;
FIG. 5 is a schematic of the pneumatic structure of FIG. 3 as configured prior to a transfer of a molded article into the holder of a first stage of the post-mold device, during start-up operation;
FIG. 6 is a schematic of the pneumatic structure of FIG. 3 as configured during the transfer of the molded article into the holder of a first stage of the post-mold device, during start-up operation;
FIG. 7 is a schematic of the pneumatic structure of FIG. 3 as configured after the receipt of the molded article into the holder of the first stage of the post-mold device, during start-up operation;
FIG. 8 is a schematic of the pneumatic structure of FIG. 3 as configured to connect the empty holders of a second and third stage of the post-mold device to a pressure source, during start-up operation;
FIG. 9 is a schematic of the pneumatic structure of FIG. 3 as configured prior to a transfer of a molded article into the holder of the second stage of the post-mold device, during start-up operation;
FIG. 10 is a schematic of the pneumatic structure of FIG. 3 as configured during the transfer of the molded article into the holder of the second stage of the post-mold device, during start-up operation;
FIG. 11 is a schematic of the pneumatic structure of FIG. 3 as configured after the receipt of the molded article into the holder of the second stage of the post-mold device, during start-up operation;
FIG. 12 is a schematic of the pneumatic structure of FIG. 3 as configured to connect the empty holder of the third stage of the post-mold device to a pressure source, during start-up operation;
FIG. 13 is a schematic of the pneumatic structure of FIG. 3 as configured prior to a transfer of a molded article into the holder of the third stage of the post-mold device, during start-up operation;
FIG. 14 is a schematic of the pneumatic structure of FIG. 3 as configured during the transfer of the molded article into the holder of the third stage of the post-mold device, during start-up operation;
FIG. 15 is a schematic of the pneumatic structure of FIG. 3 as configured after the receipt of the molded article into the holder of the third stage of the post-mold device, during start-up operation;
FIG. 16 is a schematic of the pneumatic structure of FIG. 3 as configured to connect the holder of the first stage of the post-mold device to the pressure source as the molded article is ejected therefrom, during normal operation;
FIG. 17 is a schematic of the pneumatic structure of FIG. 3 as configured prior to a transfer of a next molded article into the holder of the first stage of the post-mold device, during normal operation;
FIG. 18 is a schematic of the pneumatic structure of FIG. 3 as configured during the transfer of the next molded article into the holder of the first stage of the post-mold device, during normal operation;
FIG. 19 is a schematic of the pneumatic structure of FIG. 3 as configured after the receipt of the molded article into the holder of the first stage of the post-mold device, during normal operation;
FIG. 20 is a schematic of the pneumatic structure of FIG. 3 as configured to connect the holder of the second stage of the post-mold device to the pressure source as the molded article is ejected therefrom, during normal operation;
FIG. 21 is a schematic of the pneumatic structure of FIG. 3 as configured prior to a transfer of a next molded article into the holder of the second stage of the post-mold device, during normal operation;
FIG. 22 is a schematic of the pneumatic structure of FIG. 3 as configured during the transfer of the next molded article into the holder of the second stage of the post-mold device, during normal operation;
FIG. 23 is a schematic of the pneumatic structure of FIG. 3 as configured after the receipt of the molded article into the holder of the second stage of the post-mold device, during normal operation;
FIG. 24 is a schematic of the pneumatic structure of FIG. 3 as configured to connect the holder of the third stage of the post-mold device to the pressure source as the molded article is ejected therefrom, during normal operation;
FIG. 25 is a schematic of the pneumatic structure of FIG. 3 as configured prior to a transfer of a next molded article into the holder of the third stage of the post-mold device, during normal operation;
FIG. 26 is a schematic of the pneumatic structure of FIG. 3 as configured during the transfer of the next molded article into the holder of the third stage of the post-mold device, during normal operation;
FIG. 27 is a schematic of the pneumatic structure of FIG. 3 as configured after the receipt of the molded article into the holder of the third stage of the post-mold device, during normal operation.
The drawings are not necessarily to scale and are may be illustrated by phantom lines, diagrammatic representations and fragmentary views. In certain instances, details that are not necessary for an understanding of the exemplary embodiments or that render other details difficult to perceive may have been omitted.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
FIG. 3 is a schematic representation of a pneumatic structure 160 according to a first exemplary embodiment connected with empty holders 150-1, 150-2, 150-3 of a multi-stage post-mold device (i.e. holder 150-1 is from the first stage of the post-mold device, holder 150-2 is from the second stage of the post-mold device, and holder 150-3 is from the third stage of the post-mold device). The pneumatic structure 160 is shown as configured prior to a startup operation of the post-mold device. The holders 150-1, 150-2, 150-3 are preferably configured in accordance with U.S. Pat. No. 6,951,453, as described hereinbefore. Accordingly, the holders 150-1, 150-2, 150-3 each includes a porous member having an inside surface that is profiled to substantially reflect a shape of a portion of an outside surface of a molded article 2 (shown with reference to FIGS. 4 through 27) to be cooled. The holders 150-1, 150-2, 150-3 each include a coupling structure (not shown) for connecting the porous member to the pneumatic structure 160, whereby pneumatic pressure may be controlled (i.e. above or below ambient) adjacent the inside surface of the porous member.
The pneumatic structure 160 preferably includes a first vacuum source 164, a second vacuum source 166, and a set of two-way pneumatic control valves 162-1, 162-2, 163-3, 170, 172 for alternately connecting the holders 150-1, 150-2, 150-3 of the post-mold device to one of the first vacuum source 164 and the second vacuum source 166. Of course, other types and combination of control valves may be used to accomplish the same pneumatic connections, as detailed hereinafter. For example, the set of two-way control valves 162-1, 162-2, 163-3, 170, 172 could be replaced with a combination of three-way valves, or a single valve could be used, if available, having corresponding number of valve positions. The first set of valves 162-1, 162-2, 162-3 are controllable, by molding machine controller 30, for connecting the holders 150-1, 150-2, 150-3 with one of: (i) the first vacuum source 164; and (ii) a second control valve 170. The second control valve 170 is controllable, by the molding machine controller 30, for connecting the first valves 162-1, 162-2, 162-3 with one of: i) the second vacuum source 166; and (ii) a third control valve 172. The third control valve 172 is controllable, by the molding machine controller 30, for connecting the second valve 170 with one of: (i) a pressure source 176 (i.e. pneumatic overpressure); and (ii) an atmospheric pressure source 174. In so doing, the controller 30 can configure the valves 162-1, 162-2, 162-3, 170, 172 to connect each of the holders 150-1, 150-2, 150-3 to any one of the first and second vacuum sources 164, 166, the pressure source 176, and the atmospheric pressure source 174.
Preferably, the first and second vacuum sources 164, 166 includes vacuum tanks connected to a vacuum pump 178 for the sake of maintaining a predetermined vacuum pressure therein. Preferably, a check valve 168 separates the first and second vacuum sources 164, 166, the check valve being oriented to prevent overpressure in the second vacuum source 166, relative to the first vacuum source 164, from pressurizing the first vacuum source 164. In particular, it is economically advantageous to configure the second vacuum source 166 to have a much larger volumetric capacity than the first vacuum source 164, whereby the second vacuum source 166, during normal operation of the post-mold device, is used primarily for drawing a predetermined vacuum pressure in the holder 150-1, 150-2, 150-3, before the evacuated holder 150-1, 150-2, 150-3 is connected to the smaller first vacuum source 164 for maintaining, or further adjusting, the predetermined vacuum pressure. Accordingly, the check valve 168 is preferably oriented to prevent the loss of vacuum pressure from the first vacuum source 164 to the second vacuum source 166.
In accordance with an alternative embodiment of the pneumatic structure 160 (not shown), at least one of the first and second vacuum sources 164, 166 include a vacuum pump 178.
In operation, a method of controlling a pneumatic structure 160 for a post-mold device preferably includes the steps of: (i) configuring the control valves 162-1, 162-2, 162-3, 170, 172 to connect a holder 150-1, 150-2, 150-3 of the post-mold device to one of a first and second vacuum source 164, 166 for receiving a molded article therein; (ii) drawing a predetermined vacuum pressure in the occupied holder 150-1, 150-2, 150-3 using the one of the first and second vacuum source 164, 166; (iii) configuring the control valves 162-1, 162-2, 162-3, 170, 172 to connect the respective holder 150-1, 150-2, 150-3 of the post-mold device to the other one of the first and second vacuum source 164, 166; and (iv) controlling the vacuum pressure in the holder 150-1, 150-2, 150-3 using the other of the first and second vacuum source 164, 166. The process may also include the subsequent step(s) of configuring the control valves 162-1, 162-2, 162-3, 170, 172 to isolate the respective holder 150-1, 150-2, 150-3 from the first and second vacuum source 164, 166 and to connect the respective holder 150-1, 150-2, 150-3 to one of the pressure source 176 and the atmospheric pressure source 174, for example, to effect a pressure induced mobility of a molded article 2 and/or to condition the respective holder 150-1, 150-2, 150-3 (e.g. cleanse the pores of the porous member).
Where the post-mold device includes a plurality of holder stages the method preferably includes the steps of connecting one of the first and second vacuum sources 164, 166 to a holder 150-1, 150-2, 150-3 of at least one of the plurality of holder stages for drawing an initial predetermined vacuum pressure in the holder 150-1, 150-2, 150-3, and thereafter the holder 150-1, 150-2, 150-3 of the at least one of the plurality of holder stages is switched to the other one of the first and second vacuum sources 164, 166, for sustaining the vacuum pressure in the holder 150-1, 150-2, 150-3 thereof, as a holder 150-1, 150-2, 150-3 of another of the plurality of holder stages is connected to the one of the first and second vacuum sources 164, 166 for drawing a predetermined vacuum pressure therein.
With reference to the remaining FIGS. 4 through 27, the operation of the pneumatic structure 160 of the presently preferred embodiment is depicted during an initial start-up operation, and thereafter during normal operation.
FIG. 4 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to connect the empty holders 150-1, 150-2, 150-3 of the multi-stage post-mold device to a pressure source 176, during start-up operation, for the sake of cleansing the pores of the porous member, of the holders 150-1, 150-2, 150-3, by means of a pneumatic overpressure. The vacuum tanks of the first and second vacuum source 164, 166 are preferably evacuated during this period by vacuum pump 178. During this period the post-mold device is moved to an in-mold position to receive molded articles 2 from the mold 8, 9 (FIG. 1).
FIG. 5 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holders 150-1, 150-2, 150-3 to a connection with the atmospheric pressure source 174, during start-up operation, prior to a transfer of a molded article 2 into the holder 150-1 of a first stage of the post-mold device. During this stage of operation, the post-mold device stops in the in-mold position adjacent the mold 8, 9 (FIG. 1).
FIG. 6 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holder 150-1 of the first stage to the first vacuum source 164, during start-up operation, for the sake of receiving the molded article 2 in the holder 150-1 and for achieving a predetermined vacuum pressure therein. During this step of operation it is expected that the vacuum pressure will drop in both tanks.
FIG. 7 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 after the receipt of the molded article 2 into the holder 150-1 of the first stage of the post-mold device, during start-up operation, as the first and second vacuum sources 164, 166 are evacuated by the vacuum pump 178. During this step of operation, the post-mold device is moved to an outboard position away from the mold 8, 9 where it may dwell, as required, subsequently the post-mold device then starts moving back to the in-mold position.
FIG. 8 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the empty holders 150-2, 150-3 of the second and third stages of the post-mold device to the pressure source 176, during start-up operation, to cleanse the pores of the porous member of the holders 150-2, 150-3.
FIG. 9 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the empty holders 150-2, 150-3 of the second and third stages of the post-mold device to the atmospheric pressure source 174, during start-up operation, prior to a transfer of a molded article 2 into the holder 150-2 of the second stage of the post-mold device. During this stage of operation, the post-mold device stops in the in-mold position adjacent the mold 8, 9 (FIG. 1).
FIG. 10 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holder 150-2 of the second stage to the first vacuum source 164, during start-up operation, for the sake of receiving the molded, article 2 in the holder 150-2 and for achieving a predetermined vacuum pressure therein. During this step of operation it is expected that the vacuum pressure will drop in both tanks.
FIG. 11 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 after the receipt of the molded article 2 into the holder 150-2 of the second stage of the post-mold device, during start-up operation, as the first and second vacuum sources 164, 166 are evacuated by the vacuum pump 178. During this step of operation, the post-mold device is moved to an outboard position away from the mold 8, 9 where it may dwell, as required, subsequently the post-mold device then starts moving back to the in-mold position.
FIG. 12 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the empty holder 150-3 of the third stage of the post-mold device to the pressure source 176, during start-up operation, to cleanse the pores of the porous member of the holder 150-3.
FIG. 13 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the empty holder 150-3 of the third stage of the post-mold device to the atmospheric pressure source 174, during start-up operation, prior to a transfer of a molded article 2 into the holder 150-3 of the third stage of the post-mold device. During this stage of operation, the post-mold device stops in the in-mold position adjacent the mold 8, 9 (FIG. 1).
FIG. 14 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holder 150-3 of the third stage to the second vacuum source 166 alone, during normal operation, for the sake of receiving the molded article 2 in the holder 150-3 and for achieving a predetermined vacuum pressure therein.
FIG. 15 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holder 150-3 of the third stage to the first vacuum source 164, during normal operation, to maintain, or further adjust, the vacuum pressure in the holder 150-3 of the third stage. During this stage of operation, the second vacuum source 166 is preferably evacuated by the vacuum pump 178.
FIG. 16 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holder 150-1 of the first stage of the post-mold device to the pressure source 176, during normal operation, to assist with the release of the molded article 2 from the holder 150-1 and to cleanse the pores of the porous member of the holder 150-1.
FIG. 17 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the empty holder 150-1 of the first stage of the post-mold device to the atmospheric pressure source 174, during normal operation, prior to a transfer of the next molded article 2 into the holder 150-1 of the first stage of the post-mold device. During this stage of operation, the post-mold device stops in the in-mold position adjacent the mold 8, 9 (FIG. 1).
FIG. 18 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holder 150-1 of the first stage to the second vacuum source 166 alone, during normal operation, for the sake of receiving the molded article 2 in the holder 150-1 and for achieving a predetermined vacuum pressure therein.
FIG. 19 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holder 150-1 of the first stage to the first vacuum source 164, during normal operation, to maintain, or further adjust, the vacuum pressure in the holder 150-1 of the first stage. During this stage of operation, the second vacuum source 166 is preferably evacuated by the vacuum pump 178.
FIG. 20 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holder 150-2 of the second stage of the post-mold device to the pressure source 176, during normal operation, to assist with the release of the molded article 2 from the holder 150-2 and to cleanse the pores of the porous member of the holder 150-2.
FIG. 21 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the empty holder 150-2 of the second stage of the post-mold device to the atmospheric pressure source 174, during normal operation, prior to a transfer of the next molded article 2 into the holder 150-2 of the second stage of the post-mold device. During this stage of operation, the post-mold device stops in the in-mold position adjacent the mold 8, 9 (FIG. 1).
FIG. 22 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holder 150-2 of the second stage to the second vacuum source 166 alone, during normal operation, for the sake of receiving the molded article 2 in the holder 150-2 and for achieving a predetermined vacuum pressure therein.
FIG. 23 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holder 150-2 of the second stage to the first vacuum source 164, during normal operation, to maintain, or further adjust, the vacuum pressure in the holder 150-2 of the second stage. During this stage of operation, the second vacuum source 166 is preferably evacuated by the vacuum pump 178.
FIG. 24 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holder 150-3 of the third stage of the post-mold device to the pressure source 176, during normal operation, to assist with the release of the molded article 2 from the holder 150-3 and to cleanse the pores of the porous member of the holder 150-3.
FIG. 25 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the empty holder 150-3 of the third stage of the post-mold device to the atmospheric pressure source 174, during normal operation, prior to a transfer of the next molded article 2 into the holder 150-3 of the third stage of the post-mold device. During this stage of operation, the post-mold device stops in the in-mold position adjacent the mold 8, 9 (FIG. 1).
FIG. 26 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holder 150-3 of the third stage to the second vacuum source 166 alone, during normal operation, for the sake of receiving the molded article 2 in the holder 150-3 and for achieving a predetermined vacuum pressure therein.
FIG. 27 depicts the pneumatic structure 160 of FIG. 3 with the valves 162-1, 162-2, 162-3, 170, 172 configured to switch the holder 150-3 of the third stage to the first vacuum source 164, during normal operation, to maintain, or further adjust, the vacuum pressure in the holder 150-3 of the third stage. During this stage of operation, the second vacuum source 166 is preferably evacuated by the vacuum pump 178.
The operation of the pneumatic structure 160 then continues to cycle in accordance with the normal mode of operation.
A technical effect of the preferred embodiment of the present invention, amongst others, is a pneumatic structure 160 that isolates the holders 150-1, 150-2, 150-3 of the post-mold device, occupied by molded articles 2, from vacuum pressure variations for the sake of avoiding cooling related defects in the molded article 2.
Another technical effect, amongst others, of the preferred embodiment includes a cost effective pneumatic structure 160 that avoids having a dedicated vacuum source for each stage of the post-mold device, and that may also operate using a single vacuum pump 178.
In accordance with the forgoing it is preferred, but not necessary, to completely disconnect one of the first vacuum source 164, second vacuum source 166, pressure source 176, and the atmospheric pressure source 174 from the holder 150 before connecting another one thereof. Hence, it would be within the scope of the exemplary embodiment that the control valve 162, 170, 172 may simultaneously connect more than one of one of the first vacuum source 164, second vacuum source 166, pressure source 176, and the atmospheric pressure source 174 to the holder 150 of the device 115 for a transitory moment of time while switching therebetween.
The description of the exemplary embodiments provides examples of the present invention, and these examples do not limit the scope of the present invention. It is understood that the scope of the present invention is limited by the claims. The concepts described above may be adapted for specific conditions and/or functions, and may be further extended to a variety of other applications that are within the scope of the present invention. Having thus described the exemplary embodiments, it will be apparent that modifications and enhancements are possible without departing from the concepts as described. Therefore, what is to be protected by way of letters patent are limited only by the scope of the following claims:
Patent Application
20080023883
