Integrated duplex countershaft gear structure and assembly body of integrated duplex countershaft gear structure and countershaft

Abstract

The invention provides an integrated duplex countershaft gear structure and an assembly body of the integrated duplex countershaft gear structure and a countershaft, and belongs to the technical field of gearbox accessories. The assembly body of the integrated duplex countershaft gear structure and the countershaft comprises the countershaft and the integrated duplex countershaft gear structure; an integrated duplex countershaft gear structure comprises two countershaft gears and a gear spacer bush connected with the two countershaft gears. Countershaft assembly holes are formed in the centers of the countershaft gear and the gear spacer bush; the auxiliary shaft assembly hole is a conical hole; the taper of the auxiliary shaft is matched with the taper of the auxiliary shaft assembly hole, and the auxiliary shaft is in interference fit with the auxiliary shaft assembly hole. It can be ensured that the countershaft gear works reliably and does not rotate, the assembly requirement is met, and the part cost is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of gearbox accessories, and specifically discloses an integrated double-jointed countershaft gear structure and an assembly thereof with the countershaft. Background Art

[0002] In the existing light truck gearbox, the countershaft gear is two independent units, which are often assembled on the countershaft through interference fit. Through the elastic deformation of the material at the junction of the two and the assembly interference, positive pressure is generated between the mating surfaces. The torque is transmitted by the friction generated by this positive pressure during operation. Appropriate torque transmission capacity design is an important guarantee for the reliable operation of the gearbox. At present, the market products mainly increase the torque transmission capacity through the following two methods: one is to process the keyway between the countershaft and the matching countershaft gear, and then assemble the long flat key, relying on the side of the key to transmit the torque, which will increase the processing procedures and increase the cost of parts. After the keyway is processed, the strength of the countershaft and the countershaft gear will inevitably be weakened; the other is to increase the torque transmission capacity by increasing the interference between the countershaft gear and the countershaft, which often causes assembly difficulties, and even causes the countershaft gear to not be pressed into place at one time during assembly, and the countershaft peels, resulting in a waste of resources. In addition, the above two methods have a large number of parts and an increase in processing surfaces, which in turn increases costs. Summary of the invention

[0003] The present invention provides an integrated double countershaft gear structure and an assembly thereof with the countershaft, which can improve the problem of rotation of the countershaft gear of the gearbox when transmitting torque and low reliability, while reducing costs and improving the difficulty of assembling the countershaft gear.

[0004] The integrated double countershaft gear structure provided by the present invention comprises two countershaft gears and a gear spacer sleeve connecting the two countershaft gears; a countershaft assembly hole is arranged at the center of the countershaft gears and the gear spacer sleeve; and the countershaft assembly hole is a tapered hole.

[0005] In the above-mentioned integrated double countershaft gear structure, the two countershaft gears and the gear spacer are an integral structure.

[0006] In the above-mentioned integrated double countershaft gear structure, the countershaft assembly hole is completed in one process, with a roughness Ra of 0.8μm, a taper of 1.5°, and a roundness of 0.008mm.

[0007] In the above-mentioned integrated double countershaft gear structure, the number of countershaft gear machined end faces is 2, and the roughness Ra is 1.6 μm.

[0008] In the above-mentioned integrated double countershaft gear structure, the wall thickness of the gear spacer sleeve is not less than 5 mm.

[0009] The integrated double countershaft gear structure and countershaft assembly provided by the present invention comprises a countershaft and the integrated double countershaft gear structure; the taper of the countershaft matches the taper of the countershaft assembly hole, and the countershaft and the countershaft assembly hole are interference fit.

[0010] The above-mentioned assembly of the integrated double countershaft gear structure and the countershaft has an interference fit of 44 to 72 μm after the countershaft and the integrated double countershaft gear structure are assembled, and the safety factor is above 4.

[0011] Compared with the prior art, the present invention has the following beneficial effects.

[0012] 1. In the integrated double-jointed countershaft gear structure provided by the present invention, the countershaft assembly hole adopts a tapered hole, which has a larger matching area with the countershaft under the condition of a certain axial length, can improve the torque transmission capacity, and has high reliability.

[0013] 2. The countershaft assembly hole is machined once, and the integrated double countershaft gear structure has high coaxiality with the countershaft.

[0014] 3. It can reduce the number of gear end surface processing and the number of parts, thus reducing costs.

[0015] 4. The integrated double countershaft gear structure changes the assembly of the countershaft gear and the countershaft from two times to one time, thus improving the assembly efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a structural schematic diagram of an integrated double countershaft gear structure;

[0018] Figure 2 It is a cross-sectional view of the integrated double countershaft gear structure;

[0019] Figure 3 It is the assembly drawing of the integrated double countershaft gear structure and the countershaft.

[0020] In the figure: 1. countershaft gear; 2. gear spacer; 3. countershaft assembly hole; 4. countershaft; 5. retaining spring. DETAILED DESCRIPTION

[0021] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] Example 1

[0023] In order to ensure that the countershaft gear works reliably and does not rotate, while meeting assembly requirements and reducing parts costs, the present embodiment provides an integrated double countershaft gear structure, including two countershaft gears 1 and a gear spacer 2 connecting the two countershaft gears 1; a countershaft assembly hole 3 is provided in the center of the countershaft gear 1 and the gear spacer 2; the countershaft assembly hole 3 is a tapered hole.

[0024] In the above-mentioned integrated double countershaft gear structure, the two countershaft gears 1 and the gear spacer sleeve 2 are an integral structure.

[0025] In the above-mentioned integrated double countershaft gear structure, the countershaft assembly hole 3 is completed in one process, has high coaxiality with the countershaft, a roughness Ra of 0.8 μm, a taper of 1.5°, and a roundness of 0.008 mm.

[0026] In the above-mentioned integrated double countershaft gear structure, the number of machined end faces of the countershaft gear 1 is 2, and the roughness Ra is 1.6 μm.

[0027] In the above-mentioned integrated double countershaft gear structure, the wall thickness of the gear spacer sleeve 2 is not less than 5 mm.

[0028] The above-mentioned integrated double countershaft gear structure is achieved by designing two independent countershaft gears 1 into an integrated double gear structure, wherein the countershaft assembly hole 3 is a tapered hole structure, which has a larger mating area with the countershaft under the condition of a certain axial length, thereby improving the torque transmission capacity and working reliability of the countershaft gear 1, while reducing the number of parts and the number of processed surfaces to reduce costs.

[0029] Example 2

[0030] The assembly of the integrated double countershaft gear structure and the countershaft provided in this embodiment comprises a countershaft 4 and the integrated double countershaft gear structure; the taper of the countershaft 4 matches the taper of the countershaft assembly hole 3, the countershaft 4 and the countershaft assembly hole 3 are interference fit and the axial position is limited by the retaining spring 5. During assembly, the countershaft assembly hole 3 is equivalent to a large chamfered structure, and has a guiding effect when the whole is pressed into a countershaft with the same taper, making assembly easier.

[0031] The above-mentioned assembly of the integrated double countershaft gear structure and the countershaft, the interference of the countershaft 4 and the integrated double countershaft gear structure after assembly is 44 to 72 μm, and the safety factor is above 4.

[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An integrated double countershaft gear structure, characterized in that: It includes two countershaft gears and a gear spacer sleeve connecting the two countershaft gears; A countershaft assembly hole is provided at the center of the countershaft gear and the gear spacer; The secondary shaft assembly hole is a tapered hole.

2. The integrated double countershaft gear structure according to claim 1, characterized in that: The two countershaft gears and the gear spacer are of an integral structure.

3. The integrated double countershaft gear structure according to claim 2, characterized in that: The secondary shaft assembly hole is completed in one process, with a roughness Ra of 0.8 μm, a taper of 1.5°, and a roundness of 0.008 mm.

4. The integrated double countershaft gear structure according to claim 3, characterized in that: The number of machined end faces of the countershaft gear is 2, and the roughness is Ra 1.6μm.

5. The integrated double countershaft gear structure according to claim 4 is characterized in that: The wall thickness of the gear spacer shall not be less than 5mm.

6. An integrated double countershaft gear structure and countershaft assembly, characterized in that: A device comprising a countershaft and an integrated double countershaft gear structure as claimed in any one of claims 1 to 5; The taper of the secondary shaft matches the taper of the secondary shaft assembly hole, and the secondary shaft and the secondary shaft assembly hole are interference fit.

7. The integrated double countershaft gear structure and countershaft assembly according to claim 6, characterized in that: After the countershaft and the integrated double countershaft gear structure are assembled, the interference is 44 to 72 μm, and the safety factor is more than 4.

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