Method of producing pressed paper piece and apparatus therefor

Patent metadata

Field	Value
Publication number	US-9630372-B2
Application number	US-201314371130-A
Country	US
Kind code	B2
Filing date	Jan 10, 2013
Priority date	Jan 30, 2012
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

The objective of the present invention is to provide a method of forming a pressed paper piece by deep drawing a sheet of blank that is primarily made of paper in use of a punch and a die, and a production apparatus for implementing the method, whereby no distinguishable wrinkles are formed in upright portions of the pressed paper piece. The method of producing a pressed paper piece according to the present invention, implemented when deep drawing a sheet-like blank that is primarily made of paper in use of a punch and a die, includes maintaining a predetermined gap between a first blank holder and the die in an outer peripheral region of a process portion of the blank and applying a pressure to a radially inner region thereof via a second blank holder, thereby reducing wrinkling by an effect of integrated functions exerted in both regions of the blank.

First claim

The invention claimed is:

1. An apparatus for producing a pressed paper piece by deep drawing a sheet-like blank that is primarily made of paper in use of a punch and a die, the apparatus comprising:
means for maintaining a predetermined gap S between a lower surface of a first blank holder and an upper surface of the die during deep drawing, with the first blank holder being arranged in an outer peripheral region of a process portion of the blank, and a second blank holder having pressing means being arranged in a radially inner region in the process portion of the blank,
wherein the second blank holder has a lower surface protruding more than the lower surface of the first blank holder, with a difference Z therebetween being S−T≦Z<S, where T is the thickness of the blank.

2. The apparatus for producing a pressed paper piece according to claim 1 , wherein the first blank holder has a sharp outer circumferential edge that also serves as a cutter for cutting the blank.

3. The apparatus for producing a pressed paper piece according to claim 2 , further comprising a lubricating oil supply member for lubricating the upper surface of the die arranged opposite a lower end face of the first blank holder.

4. The apparatus for producing a pressed paper piece according to claim 1 , further comprising a lubricating oil supply member for lubricating the upper surface of the die arranged opposite a lower end face of the first blank holder.

Assignees

• Toyo Seikan Group Holdings Ltd
• Tokan Kogyo Co Ltd

Inventors

• Takao Kenichi
• Kunihiro Ichiro
• Ogawa Masahiro
• Okabe Seiji

Classifications

• B29L2031/7132

  Bowls, Cups, Glasses · CPC title

• B29D22/00

  Producing hollow articles (tubular articles B29D23/00; pneumatic tyres B29D30/00) · CPC title

• B31F1/0077 Primary

  Shaping by methods analogous to moulding, e.g. deep drawing techniques · CPC title

• B31B50/592

  using punches or dies · CPC title

• B29K2001/00

  Use of cellulose, modified cellulose or cellulose derivatives, e.g. viscose, as moulding material · CPC title