EP0776713A2
Expired / Lapsed
EP
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A method for laminate forming a sand mould and a method for producing a casting using the same
Assignee: Toyota Motor Corp
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Filing: 1996-10-29
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Granted: —
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Expires: 2016-10-29
Abstract
Abstract After sand of one layer is loaded into a sand layer elevator (20), a shading mask (38) is positioned above the sand, and a diffused laser beam is irradiated from a diffused laser irradiating source (16). Thereby, a predetermined range of sand under the shading mask (38) is exposed and this exposed portion is cured. This operation is repeated for a predetermined number of sand layers and cured portions are piled up to directly form a 3-D sand mould. Particularly, a diffused laser beam is used to cure a wide range of sand at a time, thereby making sand mould mass-production possible.
Inventors
- 👤 Hiromoto Satoh
- 👤 Yukio Otsuka
- 👤 Motoaki Ozaki
- 👤 Masuo Shimizu
- 👤 Yuji Okada
- 👤 Yoshizumi Senda
- 👤 Soya Takagi
- 👤 Masaru Ogura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 22:54
CPC Classifications
B; B22; B22C; B22C9/00; B22C9/02; B22C1/00; B22C1/16; B22C1/20; B22C1/22; B23; B23K; B23K26/00; B29; B29C; B29C33/00; B29C33/38; B29C33/3807; B29C64/00; B29C64/10; B29C64/141; B29C64/153; B29C64/40; Y; Y02; Y02P; Y02P10/00; Y02P10/25
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
97 words
A method for forming a sand mould as a 3-D form comprising the steps of: forming a sand layer by accumulating sand coated with a thermosetting resin in the form of a thin layer; arranging a mask having an opening in a predetermined portion above the formed sand layer; heating a portion of the sand layer located below the opening through the arranged mask to solidify the portion; forming one layer of a sectional form of the sand mould; and piling up sectional forms to form a sand mould as a 3-D form by repeating these processes.
Claim 2
Dependent Claim
41 words
The method for forming a sand mould according to claim 1, wherein heating through the mask is carried out by irradiating a diffused laser beam onto the sand layer through the mask to heat an exposed portion of the sand layer.
Claim 3
Dependent Claim
56 words
The method for forming a sand mould according to claim 1, wherein, when an island corresponding to a core is present in the mask, a mask in which this island is supported by supports extending from other mask portions is used and the positions of the supports are made different between masks for adjacent sand layers.
Claim 4
Dependent Claim
36 words
The method for forming a sand mould according to claim 1, wherein heating through the mask is carried out by arranging a heat source above the mask to heat an exposed portion of the sand layer.
Claim 5
Dependent Claim
42 words
The method for forming a sand mould according to claim 1, wherein a heat source having a relatively large area which is divided into multiple heat source elements is arranged above the mask to heat an exposed portion of the sand layer.
Claim 6
Dependent Claim
57 words
The method for forming a sand mould according to claim 5, wherein the divided heat source elements can be turned on and off independently for respective divided blocks of the area of the sand layer and only heat source elements located above an exposed portion of a heat insulating mask are turned on in the heating step.
Claim 7
Independent Claim
57 words
The method for forming a sand mould according to any one of claims 1 to 6, wherein the formation of the sand mould is carried out in a plurality of stations to form a plurality of sand moulds in parallel and the mask is movable among the plurality of stations and shared by the plurality of stations.
Claim 8
Dependent Claim
38 words
The method for forming a sand mould according to claim 1, wherein a first sand layer is formed on and adhered to a pedestal for supporting a sand layer stably at the time of forming the sand layer.
Claim 9
Dependent Claim
34 words
The method for forming a sand mould according to claim 1, wherein at least two different types of sands which differ in grain diameter are used as the sand used in the sand layer.
Claim 10
Dependent Claim
48 words
The method for forming a sand mould according to claim 9, wherein, in the step of forming a sand layer, the sand having a relatively large grain diameter is first sprinkled and then the sand having a relatively small grain diameter is sprinkled to form one sand layer.
Claim 11
Dependent Claim
35 words
The method for forming a sand mould according to claim 1, wherein, in the step of forming a sand layer, the sand is compressed by vibration generated by an oscillator to form a sand layer.
Claim 12
Dependent Claim
49 words
The method for forming a sand mould according to claim 1, wherein, in the step of forming a sand layer, the sand layer is formed to a thickness 1 to 10 % larger than the thickness of a required sand layer and then compressed by a plate from above.
Claim 13
Dependent Claim
84 words
The method for forming a sand mould according to claim 1, wherein the mask is manufactured based on a mask form obtained after the arrangement of supports by the following steps: creating a mask form based on a 2-D sectional form of a casting form; detecting an island portion surrounded by a space portion from the thus created mask form; and automatically arranging supports at predetermined intervals in the space portion surrounding the detected island portion based on parallel lines arranged at predetermined intervals.
Claim 14
Dependent Claim
83 words
The method for forming a sand mould according to claim 1, wherein the mask is manufactured based on a mask form obtained after the arrangement of supports by the following steps: creating a mask form based on a 2-D sectional form of a casting form; detecting an island portion surrounded by a space portion from the thus created mask form; and automatically arranging supports in the space portion surrounding the detected island portion based on a lattice of supports arranged at predetermined intervals.
Claim 15
Dependent Claim
100 words
The method for forming a sand mould according to claim 1, wherein the mask is manufactured based on a mask form obtained after the arrangement of supports has been changed by the following steps: creating a mask form based on a 2-D sectional form of a casting form; detecting an island portion surrounded by a space portion from the thus created mask form; automatically determining the arrangement positions of supports for supporting the island portion based on predetermined rules; and changing the position of an automatically arranged support according to a connection state between the island portion and the support.
Claim 16
Independent Claim
38 words
The method for forming a sand mould according to any one of claims 13 to 15, wherein, in the step of automatically arranging supports, the positions of the supports are made different between masks used for adjacent layers.
Claim 17
Independent Claim
41 words
The method for forming a sand mould according to any one of claims 13 to 15, wherein, in the step of automatically arranging supports, the positions of the supports are made different among masks used for at least three adjacent layers.
Claim 18
Independent Claim
44 words
The method for forming a sand mould according to any one of claims 13 to 17, wherein, in the step of automatically arranging supports, the island portion is judged by a closed outline and a support connecting the same outline is removed as unnecessary.
Claim 19
Dependent Claim
49 words
The method for forming a sand mould according to claim 15, wherein the position of the support is changed based on the stability of the island portion which is judged from the center position of the island portion and the connection position of the support with the island portion.
Claim 20
Independent Claim
40 words
The method for forming a sand mould according to any one of claims 13 to 19, wherein the mask is manufactured by machining a sheet metal by a laser based on a mask form in which supports have been arranged.
Claim 21
Independent Claim
35 words
A method for producing a casting comprising the step of producing a casting using a sand mould formed by the method for forming a sand mould according to any one of claims 1 to 20.
Claim 22
Independent Claim
90 words
An apparatus for forming a sand mould as a 3-D form comprising: a sand layer forming device for forming a sand layer by accumulating sand coated with a thermosetting resin in the form of a thin layer; a mask having an opening in a predetermined portion and changeably arranged above the formed sand layer; a mask changer for changing the mask arranged above the formed sand layer; and heating device for heating a portion of the sand layer located below the opening through the arranged mask to solidify the portion.
References Cited (Backward Citations)
US4247508A
Cited
US4247508B1
Cited
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