CA1156012A - Mattress mold ejection device - Google Patents

Abstract

Abstract of the Disclosure A mold having an air injection device attached centrally to the bottom, said air injection device comprising an air actuated piston that goes backwards and forwards to allow air ingress into the mold.

Description

This invention relates to a large mold and means for ~jectlng the molding product from the mold and to the method of using said mold.
In molding large objects having dimensions of several feet, difficulty has been experienced from time to time in breaking the molded article away from the mold and spreading air between -the molded article and the mold to acilitate its ready removal from the mold.
An aspect of the invention is as follows:
A mold having an air injection device attached centrally to the bottom of said mold, said device comprising an air',cylinder having a piston ram movable longitudinal therein and a bolt screwed into an end o~
the air cylinder, said ram having a head on one end thereof adapted to close an opening through the bottom of said mold when said head is flush with the inside surface of the mold and having a piston on the other end thereof actuatable by an adjustable spring, said piston having a pair of cooperating bosses, the boss the farthest removed from the head being in contact with said spring to move the head into said opening ~o alose said op~n:lng, and an air line to admit air into said cylinder ~Q movQ the boss nearest thQ head to the e~haust po~ition.
The nature of t~is lnv~n~i.on may more readlly be understood and appreclated with lts advantages by re~erence to the drawings wherein:
Fig. 1 is a partial seckion ~hrough essentially the central part of a mold 1tted with a skrlpping means shown in partial enlarged cross-section; and Fig. 2 is a vertical cross-sectional vie~ through the piston chamber of the air injection and strippi.ng .~

~1$6012 Referring more speciflcally to Fig. 1, the numeral 3 designates the mold having an opening 4 in the central part of the bottom of sald mold, fitted with an air injection or stripping device. The air hole 4 of the mold is closed or stopped when the head 9 of the piston 5 is in its extended position. Thus the face or top of the piston 6 will be ~lush with the inside surface 7 o~ the mold. It should be noted that the air in~ection device is composed o~ a ram 10 having a head 9 fitted within a piston cylinder 8. A spring means 10 positioned on and over the lower extremity of the piston ram urges the piston ram upward into close position -lA-.~

relative to -the hole 4 of the mold. The cylinder 8 is fit-ted on the outside with threads 11 to permit the cylinder to be screwed into the bottom o~ the mold 12, which also con-tains corresponding threads 13. Thus the bottom of the mold acts as a nut for -the screw o~ the air cylinder to permit it to be attached -thereto. The lower extremity of the air cylinder is shown as enlarged and screw threads 14 cut therein to permit a screw 15 such as the one shown m Fig.
1 to be screwed into the screwed roll 16 of the'cyl:inder and thus adjusts -the tension on the spring 1~ resting on the head 17 of the screw and against the boss 19 of the ram.
m e air cylinder has two openings, 20 and 21, one to receive an air hose 22 wherein air can be admitted to the cylinder and the force o~ the air will act upon the upper boss 23 to cause the piston to move downward against the force of the spring 18 to operL the hole 4 in the bottom of the mold. As the piston moves downward the air will escape through hole 4 into the cavity of the mold and since the hole 4 is essen-tially in the center o~ the mold it will cause the molded article to be separa-ted from the mold and as the air works its way to the outer edges of the mold, it will loosen the molded article Prom the mold and permit it to be readily stripped from -the mold cavi-ty, When a~r p,ressure is shut o~f, the spring will act on ~he bo~s to move the ram upward to close -the hole 4 in the mold a-t,the time -the piston h~ad contacts -the tapered sldes o:f hol~ 4.
A single or double bed mattress mold ~itted wi-th the deviG~ o~ Figs. 1 and ~ was used -to mold polyurethane ~oam ~1S~;012 mattresses. This mattress was readily stripped from the mold by admitting air through line 22 to the air cylinder at pres-sures of about 5 to 50 pounds per square inch -to break the mattress away from the mold. Then the lid was released and opened. This caused -the air pressure re-tained between the mattress and mold to èxpand and resulted in essentially pop-ping the mattre~s upward ~rom the mold.` Af-ter the mattress has popped loose from the mold i-t can be readily li~ted out and prepared for shlpping.
While certain represen-tative embodiments and details have been shown for the purpose of illustrating the invention it will be apparent to those skilled in this art tha-t various changes and modifications may be made therein without departing ~rom the spirit or scope of the invention.

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

CLAIM:

1. A mold having an air injection device attached centrally to the bottom of said mold, said device comprising an air cylinder having a piston ram movable longitudinal therein and a bolt screwed into an end of the air cylinder, said ram having a head on one end thereof adapted to close an opening through the bottom of said mold when said head is flush with the inside surface of the mold and having a piston on the other end thereof actuatable by an adjustable spring, said piston having a pair of cooperating bosses, the boss the farthest removed from the head being in contact with said spring to move the head into said opening to close said opening, and an air line to admit air into said cylinder to move the boss nearest the head to the exhaust position.