Patent Publication Number: US-2011064842-A1

Title: Cooling device for molding apparatus

Description:
BACKGROUND 
     1. Technical Field 
     The disclosure relates to cooling devices for molding apparatuses. 
     2. Description of Related Art 
     Generally, for molding thermoplastic using a thermoforming machine, such as an injection-molding machine or apparatus, the following steps are carried out. First, the thermoplastic to be molded is supplied to a thermoforming machine; the thermoplastic to be plasticized, is heated in a cylindric chamber in the machine, and then the melted plastic is injected into a die from a nozzle. Finally, the molded plastic inside the die is cooled by the conducting of cooling fluid into a plurality of conduits formed in the die. The cooling device employed in the thermoforming machine is ineffective to cool the die effectively and uniformly because of all of the surfaces of the die which are away from the conduits and which mostly cannot be cooled by the fluid inside the conduits. 
     Therefore it is desirable to provide a cooling device which can cool the molding apparatus more effectively and uniformly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded isometric view of a cooling device in accordance with an embodiment. 
         FIG. 2  is an isometric view of the cooling device of  FIG. 1  in use. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 1 , a cooling device  100  for cooling a molding apparatus is shown. The cooling device  100  includes a housing  110  and a die  120  received in the housing  110 . 
     The housing  110  is shaped corresponding to the shape and profile of the die  120 , and includes a bottom  112 , a top  114  and a plurality of sidewalls  116  interconnecting the bottom  112  and the top  114 . The bottom  112  defines a first opening  112   a  through which the die  120  is exposed. The length and the width of the first opening  112   a  are shorter than the respective counterparts of the corresponding sides of the die  120 , and are sealed by the die  120  from the inner side of the bottom  112 . The top  114  defines a second opening  114   a  therein corresponding to the first opening  112   a . The second opening  114   a  serves as the entrance for inserting the die  120  into the housing  110 . One of the sidewalls  116  defines a number of first inlets  116   a  for the passage of water into the housing  110 . Two outlets  116   b  are defined in another sidewall  116  which is opposite to the first inlets  116   a . Each of the other two sidewalls  116  defines a second inlet  116   c  adjacent to the outlets  116   b  but away from the first inlet  116   a . The first and second inlets  116   a  and  116   c  are smaller than the outlets  116   b , respectively. 
     The die  120  includes a fixing surface  122 , an opposite parting surface  124  and a number of side surfaces  126  interconnecting with the fixing surface  122  and the parting surface  124 . The die  120  is mounted with the fixing surface  122  on the bottom  112  of the housing  110  to seal the first opening  112   a . The parting surface  124  is exposed from the second opening  114   a  and is capable of matching with another die  120  to form a die cavity in which the plasticized plastic is shaped to a predefined shape or profile. Because the assembly tolerance and the manufacturing tolerance of the housing  110  and the die  120  do exist, some interstices (not shown) may get between the side surface  126  of the die  120  and the sides surrounding the second opening  114   a . The interstices can be filled and sealed by a waterproof material. A number of first passages  126   a  are formed in the die  120 , each of the first passages  126   a  spanning two opposite side surfaces  126  of the die  120 . One end of each first passage  126   a  is aligned with one of the first inlets  116   a , and the other end of the first passage  126   a  is aligned with one of the outlets  116   b . A second passage  130  is defined between the side surface  126  of the die  120  and the sidewalls  116  of the housing  110 . 
     Referring to  FIG. 2 , the cooling device  100  is used accompanying a cooling control system  200 . The cooling control system  200  includes a container  210 , a pump  220 , an inlet pipe  230 , an outlet pipe  240 , and a valve  260 . 
     The container  210  is used for storing the cooling fluid, and is communicated to the inlet of the pump  220  by a tube (not labeled). The output of the pump  220  is communicated to the first inlet  116   a  of the housing  110  by the inlet pipe  230 . The inlet pipe  230  includes a number of branched outlets  230   a , which are connected to the housing  110  and correspondingly aligned with the first inlets  116   a  and the second inlets  116   c . The outlet pipe  240  includes a number of branched inlets  240   a , which are connected to the housing  110  and aligned with the outlets  116   b . The valve  260  is connected to the outlet pipe  240 . 
     In use, the cooling fluid is drawn from the container  210  by the pump  220 , and then pumped into the housing  110  through the inlet pipe  230  and the first and second inlets  116   a  and  116   c . The cooling fluid in the housing  110  simultaneously flows through the first passage  126   a  of the die  120  and the second passage  130  between the side surface  126  and the sidewalls of the housing  110 , thereby cooling the die  120  from the inside and outside. As such, the cooling of the die  120  is improved in various aspects, such as improving cooling efficiency and shortening the cooling time. In addition, the second inlets  116   c  are adjacent to the outlets  116   b  but away from the first inlets  116   a , which thereby effectively reduces the temperature differences between two opposite ends of the die  120  respectively facing the first inlets  116   a  and the outlets  116   b , and improves the cooling uniformity of the die  120 . 
     It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the disclosure or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments of the disclosure.