Core bar positioning device of hot box sand core

Abstract

The utility model discloses a core bar positioning device of a hot box sand core, which comprises a fixed die, a movable die and a sand core cavity, an upper positioning rod and a lower positioning rod are arranged on the fixed die, a core bar ejector rod is arranged in the movable die, and a core bar is arranged in the sand core cavity. The core bar positioning device has the beneficial effects that a fixed structure of the upper positioning rod, the lower positioning rod and the core bar ejector rod is adopted, all-directional positioning of the front end, the rear end, the left side, the right side and the lower end of a core bar is realized in a hot core box mold, the core bar is prevented from inclining in the sand shooting process, the sand core forming effect is ensured, and the production efficiency is improved. And the upper positioning rod, the lower positioning rod and the core bar ejector rod are in threaded connection, repeated disassembly is not needed, high-temperature contact of operators is avoided, safety and high efficiency of production are effectively guaranteed, and the mold maintenance cost is greatly reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of sand casting, in particular to a core bone positioning device for a hot core box sand core. Background Art

[0002] The hot core box method is a method of machine-made cores in foundry production. A sand mixture made of casting sand, thermosetting resin and curing agent is injected into a core box with a heating device, and then heated to 180-250°C to heat the sand close to the surface of the core box. Under the action of temperature, its binder can be condensed and hardened in a short time to form a sand core. It does not need to be dried in a drying furnace, which has the advantages of shortening the production cycle.

[0003] During the production process, the easy-to-break area of ​​the sand core (the area with a small diameter) is generally pre-placed with an iron core bone to improve its strength. For the support and fixation of the core bone, the traditional method is to use a removable support block fixation method, that is, a live block method, but this method has the following shortcomings:

[0004] 1. Since the positioning depth of the thin and long core bone inserted into the live block is limited, it is easy to tilt during the sand shooting process. After solidification, part of the core bone will be exposed on the surface of the sand core, and the exposed part will adhere to the molten iron, affecting demolding; 2. After the sand core is formed and ejected, the core bone will often slide out when the live block is manually pulled out, which can easily destroy the sand core molding; 3. The temperature of the hot core box during production is as high as more than 200 degrees. Repeated loading and unloading of live blocks at a high frequency will not only cause mold wear but also easily burn fingers, posing a safety hazard. Utility Model Content

[0005] The utility model aims to provide a core bone positioning device for a hot core box sand core to solve the problems raised in the above background technology.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] The utility model provides a core bone positioning device for a hot core box sand core, comprising a fixed mold, a movable mold and a sand core cavity, wherein an upper positioning rod and a lower positioning rod are arranged on the fixed mold, a core bone push rod is arranged in the movable mold, and a core bone is arranged in the sand core cavity.

[0008] Furthermore, the portions of the upper positioning rod, the lower positioning rod and the core bone push rod buried in the sand core cavity have a draft angle, and the draft angle is 1.5 degrees.

[0009] Furthermore, the upper positioning rod, the lower positioning rod and the core bone ejector rod are all provided with external threads at one end connected to the fixed mold and the movable mold.

[0010] Furthermore, a square groove is formed at one end of the upper positioning rod located at the sand core cavity, an upper spring hole is formed at the external threaded end of the upper positioning rod, and a first compression spring is arranged in the upper spring hole.

[0011] Furthermore, a positioning groove is provided at one end of the lower positioning rod located in the sand core cavity, a lower spring hole is provided at the external threaded end of the lower positioning rod, and a second compression spring is provided in the lower spring hole.

[0012] Furthermore, the core bone push rod and the upper positioning rod are located on the same horizontal line, and one end of the core bone push rod close to the fixed mold is in contact with the upper positioning rod.

[0013] Furthermore, the upper and lower ends of the core bone are connected to the upper positioning rod and the lower positioning rod respectively.

[0014] Beneficial effect: A core bone positioning device for a hot core box sand core adopts a fixed structure of an upper positioning rod, a lower positioning rod and a core bone push rod, which can realize all-round positioning of the front end, rear end, left side, right side and lower end of the core bone in the hot core box mold, prevent the core bone from tilting during the sand shooting process, and ensure the sand core molding effect. The upper positioning rod, the lower positioning rod and the core bone push rod are threadedly connected, and there is no need for repeated disassembly, which avoids high-temperature contact for operators, effectively ensuring safe and efficient production and reducing mold maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is an exploded schematic diagram of the overall structure of the utility model;

[0016] Figure 2 It is a cross-sectional view of the overall structure of the utility model;

[0017] Figure 3 This is a cross-sectional view of the upper positioning rod structure of the utility model;

[0018] Figure 4 This is a cross-sectional view of the lower positioning rod structure of the utility model.

[0019] Reference numerals

[0020] 1-fixed mold, 2-movable mold, 3-sand core cavity, 4-upper positioning rod, 41-square groove, 42-upper spring hole, 43-first compression spring, 5-lower positioning rod, 51-positioning sink groove, 52-lower spring hole, 53-second compression spring, 6-core bone push rod, 7-core bone, 8-external thread. DETAILED DESCRIPTION

[0021] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0022] Example

[0023] like Figure 1-4 As shown, a core bone positioning device for a hot core box sand core comprises a fixed mold 1, a movable mold 2 and a sand core cavity 3, wherein an upper positioning rod 4 and a lower positioning rod 5 are arranged on the fixed mold 1, a core bone push rod 6 is arranged in the movable mold 2, and a core bone 7 is arranged in the sand core cavity 3.

[0024] The parts of the upper positioning rod 4, the lower positioning rod 5 and the core bone push rod 6 buried in the sand core cavity 3 have a draft angle of 1.5 degrees. The use of this draft angle is more conducive to demoulding from the sand core cavity 3. The upper positioning rod 4, the lower positioning rod 5 and the core bone push rod 6 are connected to the fixed mold 1 and the movable mold 2 at one end. An external thread 8 is provided, and a threaded connection is adopted to facilitate later replacement.

[0025] The upper positioning rod 4 is located at one end of the sand core cavity 3 and is provided with a square groove 41. The square groove 41 is a through groove for clamping the upper end of the core bone 7. The inner size of the groove matches the outer contour size of the core bone 7. An upper spring hole 42 is provided at the external threaded end of the upper positioning rod 4. A first compression spring 43 is arranged in the upper spring hole 42. After the upper positioning rod 4 is fixedly connected to the fixed mold 1 through the external thread, the built-in first compression spring 43 is used to ensure its extended length and horizontal locking fixation.

[0026] The lower positioning rod 5 is located at one end of the sand core cavity 3 and is provided with a positioning groove 51. The positioning groove 51 is a blind groove, which is used to support and fix the lower end of the core bone 7. The external threaded end of the lower positioning rod 5 is provided with a lower spring hole 52. The lower spring hole 52 is provided with a second compression spring 53. The built-in second compression spring 53 ensures its extended length and horizontal locking and fixation.

[0027] The core bone push rod 6 and the upper positioning rod 4 are located on the same horizontal line, and the end of the core bone push rod 6 close to the fixed mold 1 is in contact with the upper positioning rod 4. When the mold is closed, the core bone push rod 6 is connected to the upper positioning rod 4 to achieve positioning of the right end face of the core bone 7.

[0028] The upper and lower ends of the core bone 7 are respectively connected to the upper positioning rod 4 and the lower positioning rod 5. The core bone 7 is a square rod structure. The lower end of the core bone 7 is inserted into the positioning groove 51 of the lower positioning rod 5, and the upper end of the core bone 7 is inserted into the square groove 41 of the upper positioning rod 4 to realize the positioning control of the front end, rear end, left end and lower end of the core bone 7.

[0029] When in use, the square core bone 7 is placed in the sand core cavity 3, the lower end of the core bone 7 is inserted into the positioning groove 51 of the lower positioning rod 5, and the upper end of the core bone 7 is clamped into the square groove 41 of the upper positioning rod 4 for fixation; when closing the mold, the core bone push rod 6 moves toward the fixed mold 1 with the movable mold 2, docks with the upper positioning rod 4 and presses against the core bone 7, and then the sand shooting operation is carried out, and the coated sand is shot into the sand core cavity 3 from the sand shooting port from top to bottom, waiting for solidification and molding; after molding, the mold is opened, the movable mold 2 and the core bone push rod 6 are separated from the fixed mold 1, and at the same time, the formed sand core is ejected out of the fixed mold through the mold ejection mechanism, and finally ejected by the core bone push rod 3 on the movable mold 2, and the sand core is demolded.

[0030] Finally, it should be noted that the above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. Although the utility model is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions recorded in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the utility model content within the protection scope of the utility model.

Claims

1. A core positioning device for a hot core box sand core, comprising a fixed mold (1), a movable mold (2) and a sand core cavity (3), characterized in that: The fixed mold (1) is provided with an upper positioning rod (4) and a lower positioning rod (5), the movable mold (2) is provided with a core bone push rod (6), and the sand core cavity (3) is provided with a core bone (7).

2. The core bone positioning device of a hot core box sand core according to claim 1, characterized in that: The parts of the upper positioning rod (4), the lower positioning rod (5) and the core bone push rod (6) embedded in the sand core cavity (3) have a draft angle, and the draft angle is 1.5 degrees.

3. The core bone positioning device of a hot core box sand core according to claim 1, characterized in that: The ends of the upper positioning rod (4), the lower positioning rod (5) and the core bone push rod (6) connected to the fixed mold (1) and the movable mold (2) are all provided with external threads (8).

4. The core bone positioning device of a hot core box sand core according to claim 1, characterized in that: The upper positioning rod (4) is provided with a square groove (41) at one end of the sand core cavity (3), and an upper spring hole (42) is provided at the external threaded end of the upper positioning rod (4), wherein a first compression spring (43) is provided in the upper spring hole (42).

5. The core bone positioning device of a hot core box sand core according to claim 1, characterized in that: The lower positioning rod (5) is provided with a positioning recess (51) at one end of the sand core cavity (3), and the external threaded end of the lower positioning rod (5) is provided with a lower spring hole (52), and a second compression spring (53) is arranged in the lower spring hole (52).

6. The core bone positioning device of a hot core box sand core according to claim 1, characterized in that: The core bone push rod (6) and the upper positioning rod (4) are located on the same horizontal line, and one end of the core bone push rod (6) close to the fixed mold (1) is in contact with the upper positioning rod (4).

7. The core bone positioning device of a hot core box sand core according to claim 1, characterized in that: The upper and lower ends of the core bone (7) are respectively connected to the upper positioning rod (4) and the lower positioning rod (5).

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