Title:
MOLD FOR DISC BASE
Document Type and Number:
Japanese Patent JPH01146715
Kind Code:
A
Abstract:
PURPOSE:To make the shape of a cut section of a central hole better and prevent a resin material from overflowing to a sprue side through a gate by providing a projection mechanism to project a sprue bush to a cavity side according to the approaching movement of a mirror plate and punching the central hole of a disc base based on the projecting movement. CONSTITUTION:When an injection operation for a given resin material 78 from a nozzle 76 into a cavity through a sprue 108 and a gate 52 of a sprue bush 50 is completed, a cylinder 70 is actuated successively. Then, a piston rod 74 is projected, and a backing plate 62 is moved forward to the molding position of a disc base in contact with the end surface of an adjustable ring 44 on a movable mold 12, and also a mirror plate 16 on a fixed side is moved forward from the retracted position by a distance alpha to fill the resin material 78 into the cavity and carry out compression actuation. Also, at the same time, the sprue bush 50 is driven forward to its end side through a rack 90, gears 92 and 98 and rack 84 to seal the gate 52 and carry out punching of a central hole.
Inventors:
ASAI IKUO
SHIMOJO SHUNICHI
SHIMOJO SHUNICHI
Application Number:
JP30497487A
Publication Date:
June 08, 1989
Filing Date:
December 02, 1987
Export Citation:
Assignee:
MEIKI SEISAKUSHO KK
International Classes:
B29C45/56; B29C45/26; B29C45/38; B29D17/00; G11B3/70; G11B7/26; (IPC1-7): B29C45/26; B29C45/56; B29D17/00; G11B3/70; G11B7/24
Domestic Patent References:
| JPS5669125A | 1981-06-10 | |||
| JPS503465A | 1975-01-14 | |||
| JPS5156865A | 1976-05-18 |
Attorney, Agent or Firm:
Michio Nakajima (2 outside)