Heat Exchanger Core Assembly Without Header Plate
Solution Overview
Problem
The assembly of a heat exchanger core without a header plate faces challenges in positioning and aligning components, making the process cumbersome and difficult to achieve high mass-productivity.
Innovation Solution
A structure where a pair of plates with bulging portions are fitted in a reverse direction to form flat tubes, and an external frame with a packing holding portion is used to grasp the outer periphery of the stacked flat tubes, allowing for precise assembly and brazing, with features like different fitting structures between side walls and a convex stopper to prevent mismatches and enhance brazing reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a pair of plates are combined to form flat tubes and a casing is fitted onto the outer periphery with a bracket arranged inside, then the heat exchanger core can be assembled without a header plate, but positioning between respective components becomes extremely troublesome
Solution Approach 1:
The patent introduces a frame body as an intermediary component between the stacked flat tubes and the casing. The frame body includes an external frame portion that fits onto the stacked body and an inside flange portion with a packing holding portion, serving as a mediator that simplifies the connection and positioning between components.
Solution Approach 2:
The coupling structure is segmented into distinct functional parts: the stacked body of flat tubes, the frame body with external frame portion and inside flange portion, and the casing. This segmentation allows each component to be manufactured and positioned independently, with the frame body acting as a positioning module that guides the assembly process.
2Reliability
If multiple components are assembled manually with precise positioning, then the heat exchanger core can be constructed, but mass-productivity is difficult to achieve
Solution Approach 1:
The frame body is designed with pre-formed fitting portions and positioning features that enable preliminary positioning of the stacked body before final assembly with the casing. The external frame portion fits onto the stacked body in advance, establishing precise positioning that guides subsequent assembly steps.
Solution Approach 2:
The frame body serves as a mediator that standardizes the interface between the stacked body and casing, enabling repeatable assembly operations. The packing holding portion with its specific geometry provides a consistent positioning reference that facilitates automated or semi-automated assembly processes.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration simplifies the assembly of the heat exchanger core, ensures precise alignment, and facilitates easy and quick brazing, improving the reliability and mass-productivity of the heat exchanger by preventing mismatches and ensuring smooth fluid circulation.
Implementation Method 1
a pair of plates (5) and (6) having a pair of side walls (1) and (2) extended upward on both sides, respectively, to form a whole body into a groove shape, and bulging portions (4) formed at edges on both open sides of a groove bottom (3) on an outer side in a thickness direction orthogonally to the side walls (1) and (2) are fitted with each other facing in a reverse direction, to thereby form a flat tube (7)
Implementation Method 2
the external frame portion (10) of a pair of the frame bodies (13) are fitted onto both ends on a bulging portion (4) side of the stacked body (8) to grasp outer peripheries at both end portions of the stacked body (8) with the frame body (13)
Implementation Method 3
an annular groove (14) into which a packing for seal can be inserted is formed between a packing grasping portion (12) of the frame body (13) and both end edges of the casing (9)
Implementation Method 4
Then, in a high temperature furnace, the core is integrally brazed
Data Source
Figure 1(A)~1(B)
Figure 2(A)~2(C)
Figure 3~4
AI summary
To provide a structure of a heat exchanger core that enables the outer periphery of an stacked body 8 including an assembly of flat tubes 7 to be held in a previously fastened state and is excellent in mass-productivity. External frame portions 10 of a pair of frame bodies 13 are fitted onto both ends of a bulging portion 4 of the stacked body 8 of the flat tubes 7, and, in the state where the stacked body 8 is restrained, a casing 9 is additionally fitted onto the outer periphery thereof.