High pressure casting sand core and method of manufacturing the same

• US 5,033,530 A
• Filed: 02/20/1990
• Issued: 07/23/1991
• Est. Priority Date: 02/20/1989
• Status: Expired due to Fees

• Current Assignee: Ryobi Limited (Techtronic Industries Company Limited)
• Original Assignee: Ryobi Limited (Techtronic Industries Company Limited)
• Inventors: Sugioka, Yasuhiro, Umeda, Jyoji, Egoshi, Yoshiaki
• Primary Examiner(s): Seidel, Richard K.
• Assistant Examiner(s): Pelto, Rex E.
• Application Number:
  US07/481,191
• Time in Patent Office: 518 Days
• Field of Search: 164/131, 164/132, 164/137, 164/30, 164/228, 164/230, 164/345, 164/340
• US Class Current: 164/30
• CPC Class Codes: B22C 9/106 Vented or reinforced cores
• CPC Class Codes: B22D 17/24 Accessories for locating and holding cores or inserts

Abstract

A sand core adapted for high pressure casting is formed by a core body and a support pin to be connected to the core body. The support pin is provided with one end portion to be embedded in said core body and the other end portion projected outwardly from the core body. A connecting means is formed to the embedded portion so as to integrally connect the core body and the support pin and a support pin positioning and supporting means is formed at the projecting portion of the support pin. Positioning pins extending from a core formation mold are engaged with the positioning and supporting means so that the embedded end portion of the support pin is positioned in the cavity of the core formation mold. The cavity is filled with core sand whereby the embedded one end of the support pin is supported to integrally form the support pin and the core body. The sand core is dipped in a slurry including a sand core coating material and then heated and dried.

Claims

1. A sand core adapted for high pressure casting for forming an inner hollow portion of a cast product comprising:

a core body;

a support pin in a shape of a solid rod, said support pin being provided with one end portion embedded in said core body and the other end portion projected outwardly from said core body;

connecting means for integrally connecting the support pin and the core body, said connecting means being comprised of at least one sand receiving hole formed in the embedded one end portion of said support pin; and

positioning and supporting means for positioning and supporting said support pin with respect to at least one of a core formation and a die casting mold, said positioning and supporting means being comprised of at least one engaging hole formed in the projected other end portion of said support pin.

2. A sand core according to claim 1, wherein said support pin is made of a metal material.

3. A sand core according to claim 2, wherein said metal material is a light metal.

4. A sand core according to claim 2, wherein said metal material is an iron series material.

5. A method of manufacturing a sand core adapted for high pressure casting comprising the steps of:

preparing a support pin with means for connecting a core body with the support pin and means for positioning and supporting the support pin with respect to at least one of a core formation mold and a die casting mold;

setting the support pin in the core formation mold with an inner cavity corresponding to a core body in such a manner that one end portion having the connecting means of the support pin is located in the inner cavity said connecting means being comprised of at least one sand receiving hole formed in an embedded one end portion of said support pin and further setting the support pin in the core formation mold in such a manner that a positioning pin of the core formation mold is engaged with the positioning and supporting means formed on the other end of the support pin;

filling the inner cavity with core sand to integrally form the support pin and the core body;

dipping the core body into a slurry including a sand core coating material; and

heating and then drying the core body.

6. A method according to claim 5, wherein the positioning and supporting means of the support pin of the sand core is engaged with a hook member and the core body is then dipped in a slurry including a sand coating material.

7. The method of claim 5, wherein the inner cavity is filled such that the core sand fills said hole provided in the one end portion of the support pin located in the inner cavity.

8. A sand core adapted for high pressure casting for forming an inner hollow portion of a cast product comprising:

a core body;

a support pin in a shape of a solid rod, said support pin being provided with one end portion embedded in said core body and the other end portion projected outwardly from said core body;

connecting means for integrally connecting the support pin and the core body, said connecting means formed as a spiral thread and comprising at least one sand receiving hole formed in the embedded one end portion of said support pin; and

positioning and support means for positioning and supporting said support pin with respect to at least one of a core formation and a die casting mold, said positioning and supporting means being comprised of at least one engaging hole formed in the projected other end portion of said support pin.

9. A sand core adapted for high pressure casting for forming an inner hollow portion of a cast product comprising:

a core body;

a support pin in a shape of a solid rod, said support pin being provided with one end portion embedded in said core body and the other end portion projected outwardly from said core body;

connecting means for integrally connecting the support pin and the core body, said connecting means being formed as a knurling recessed and protruded thread comprising at least one sand receiving hole formed in the embedded one end portion of said support pin; and

positioning and support means for positioning and supporting said support pin with respect to at least one of a core formation and a die casting mold, said positioning and supporting means being comprised of at least one engaging hole formed in the projected other end portion of said support pin.