阅读说明：本技术 一种改良结构的变速箱中壳 (Gearbox middle shell with improved structure ) 是由 杨东奎 陈伟 于 2019-11-22 设计创作，主要内容包括：一种改良结构的变速箱中壳,为中空对称结构,在壳体左侧四角各设有一个凸台一、凸台二、凸台三、凸台四；在壳体顶部的一侧设有两个位置相对应的孔一和孔二,在孔一的同侧位置设有孔三；在凸台一上设有孔四、凸台二上设有孔五、凸台三上设有孔六、凸台四上设有孔七；在壳体右侧四角设有孔八、孔九、孔十。在多处结构设计定位凸台并加工定位孔,该计定位凸台不仅为后续加工提供定位基准,还可以作为零件装配总成的定位基准。(A gearbox middle shell with an improved structure is a hollow symmetrical structure, and four corners of the left side of the shell are respectively provided with a boss I, a boss II, a boss III and a boss IV; a first hole and a second hole which correspond to each other in position are formed in one side of the top of the shell, and a third hole is formed in the same side of the first hole; a hole IV is formed in the boss I, a hole V is formed in the boss II, a hole VI is formed in the boss III, and a hole VII is formed in the boss IV; eight holes, nine holes and ten holes are arranged at four corners of the right side of the shell. The positioning bosses are designed at multiple positions and are used for machining positioning holes, and the positioning bosses not only provide positioning reference for subsequent machining, but also can be used as the positioning reference of a part assembly.)

1. A gearbox middle shell with an improved structure is characterized in that the device is of a hollow symmetrical structure, and four corners of the left side of a shell are respectively provided with a boss I (1), a boss II (2), a boss III (3) and a boss IV (4); a first hole (5) and a second hole (6) which correspond to each other in position are formed in one side of the top of the shell, and a third hole (7) is formed in the same side of the first hole (5); a hole IV (8) is arranged on the boss I (1), a hole V (9) is arranged on the boss II (2), a hole VI (10) is arranged on the boss III (3), and a hole VII (11) is arranged on the boss IV (4); eight (12), nine (13) and ten (14) holes are arranged at the four corners of the right side of the shell.

Technical Field

The invention relates to the technical field of automobile manufacturing, in particular to a gearbox middle shell with an improved structure.

Background

The fourteen-gear transmission middle shell is a support part in a main part of a heavy commercial vehicle transmission system, and the load capacity of the middle shell transmission product matched with a vehicle model is 10-80 tons. The development trend of the gearbox of the Chinese medium and heavy truck is towards the direction of multi-gear large torque, and the gearbox with multi-gear large speed ratio variation range improves the dynamic property, fuel economy and gear shifting smoothness of the automobile. The gears are refined, so that a driver can select a proper position to drive according to road conditions and cargo carrying conditions, and the phenomena that a heavy vehicle cannot move at a high gear and a low gear in the driving process are reduced.

Disclosure of Invention

The invention aims to provide a gearbox middle shell with an improved structure.

In order to achieve the purpose, the invention adopts the following technical scheme: a gearbox middle shell with an improved structure is of a hollow symmetrical structure, and four corners of the left side of the shell are respectively provided with a boss I (1), a boss II (2), a boss III (3) and a boss IV (4); a first hole (5) and a second hole (6) which correspond to each other in position are formed in one side of the top of the shell, and a third hole (7) is formed in the same side of the first hole (5); a hole IV (8) is arranged on the boss I (1), a hole V (9) is arranged on the boss II (2), a hole VI (10) is arranged on the boss III (3), and a hole VII (11) is arranged on the boss IV (4); eight (12), nine (13) and ten (14) holes are arranged at the four corners of the right side of the shell.

The invention has the beneficial effects that: this device increases 2 locating holes, location boss through the configuration optimization design of gearbox mesochite, increases the plane play for the assembly accuracy of gearbox mesochite improves, and the boss design also can reduce the sand hole that appears at casting in-process casing body, and the proportion of shrinkage porosity further upgrades at the performance of original part. The bosses on the two sides provide a reference for detecting whether the shell blank is symmetrical or not in the processing and clamping process.

Drawings

FIG. 1 shows an isometric view of a transmission center housing of an embodiment of the present invention;

FIG. 2 illustrates a rear view of a transmission center housing of an embodiment of the present invention;

FIG. 3 shows a left side view of a transmission center housing of an embodiment of the present invention;

fig. 4 shows a right side view of a gearbox center housing of an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

As shown in figure 1, the gearbox middle shell with the improved structure is hollow in the casting process, a boss I (1), a boss II (2), a boss III (3) and a boss IV (4) are respectively arranged at four corners of one side of the outer portion of the shell, and according to the principle of die casting, if sand holes and shrinkage holes occur, the sand holes and the shrinkage holes can be formed in the 4 boss positions, the rate of the sand holes and the shrinkage holes occurring on the shell body can be reduced, the possibility of blank problems of parts at key positions is reduced, and the qualified rate of the parts is improved.

As shown in fig. 2, the other side of the outer part of the shell is provided with a first hole (5) and a second hole (6) which correspond to each other in position, the first step of the machining process is used for forming, and in the subsequent machining process, most of the steps adopt the two holes as clamping and positioning references, so that the precision of parts can be effectively improved. And a third hole (7) is formed in the same side position of the first hole (5), so that the light weight effect can be achieved, and parts in the shell can be assembled and adjusted more conveniently in the assembling process.

As shown in fig. 3 and 4, the left and right views of the middle shell of the novel gearbox are shown in the drawings, when the plane is machined, the plane and the hole in fig. 1 are used as positioning references, and because a boss I (1) and a boss II (2) are added in the subsequent machining process, the precision is higher when the plane is machined, on the basis, the tolerance levels of 7 key holes assembled in fig. 3 and 4 are improved, as shown in fig. 3 (8, 9, 10, 11) and fig. 4 (12, 13, 14), so that the assembly accuracy of the middle shell of the novel gearbox is improved, and the performance of parts is improved. In the machining and clamping process, four holes in the left side in a drawing 3 are used as positioning surfaces, then three holes in the right side in a drawing 4 are used as positioning surfaces, and as the shell body of the gearbox is of a symmetrical structure, the position of the center line of the shell body can be determined and marked on the tool. Therefore, in the process of machining and clamping, if the blank to be machined meets the requirements, the symmetry of the part can be judged to be qualified, and otherwise, the part is not qualified.

The invention has the beneficial technical effects that 2 positioning holes for processing are added on the first-order processing surface of the middle shell of the gearbox, as shown in (5 and 6) in figure 2, so that the positioning in the subsequent processing of the gearbox is more accurate, the processing precision grade which cannot be achieved by the original gearbox can be reached, and the integral part performance is improved. Meanwhile, the hole 7 in fig. 2 not only can play a role of light weight, but also can more conveniently adjust parts in the shell in the assembling process. The four bosses (1, 2, 3 and 4) in fig. 1 can reduce the proportion of sand holes and shrinkage cavities on the shell during casting. And because the shell in the gearbox is symmetrical, the symmetry of the shell can be checked by taking a reference of 2 surfaces in (8, 9, 10 and 11) in fig. 3 and (12, 13 and 14) in fig. 4 as the center line of the shell in the process of machining and assembling.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.