Intermediate shaft gear positioning structure of double-intermediate-shaft gearbox

Abstract

The utility model discloses a positioning structure for an intermediate shaft gear of a double-intermediate-shaft gearbox, which comprises an intermediate shaft, the intermediate shaft is sleeved with the intermediate shaft gear, a stepped hole is arranged on an assembly formed by the intermediate shaft and the intermediate shaft gear, and a cylindrical pin is arranged in the stepped hole. The stepped hole comprises a first cylinder section and a second cylinder section which are different in aperture; a rectangular key groove penetrating through the whole gear width does not need to be machined in the intermediate shaft gear, stepped holes are formed in the intermediate shaft gear and the intermediate shaft, the stepped holes are in structural mutation in the diameter direction, no stress concentration point exists for torque transmission, the torque bearing capacity is high, the stress concentration point at the chamfer position of the root of the gear key groove is eliminated, and the service life of the gear is prolonged. The strength of the gear is improved, the phenomenon that the intermediate shaft gear is broken from the root of the key groove when the transmission torque is large is avoided, and the technical problem that in the prior art, key connection between the intermediate shaft gear and the intermediate shaft is prone to causing breakage of the intermediate shaft gear is solved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the field of gearbox, specifically a kind of double intermediate shaft gearbox intermediate shaft gear positioning structure. BACKGROUND

[0002] The output shaft gear of double intermediate shaft gearbox is supported by two intermediate shaft gears and suspended on output shaft, so intermediate shaft gear has higher assembly requirement, and intermediate shaft gear is assembled on intermediate shaft to ensure strict position degree, so that there is accurate relative position between intermediate shaft gear and intermediate shaft.

[0003] Currently, the position degree of intermediate shaft gear on intermediate shaft is guaranteed by flat key or semicircular key cooperating with keyway on intermediate shaft gear and intermediate shaft. Rectangular keyway that penetrates the entire gear width needs to be processed at the inner hole of intermediate shaft.

[0004] And this structure for guaranteeing the position degree of intermediate shaft gear by key and keyway needs to process a long keyway on intermediate shaft gear, and stress concentration point is formed at the chamfered portion of keyway root, which can cause intermediate shaft gear to break from keyway root when transmitting large torque. SUMMARY

[0005] In view of the deficiencies in the prior art, the utility model aims at providing a double intermediate shaft gearbox intermediate shaft gear positioning structure to solve the technical problem that the key connection between intermediate shaft gears in the prior art can easily cause intermediate shaft gears to break.

[0006] To solve the above technical problems, the utility model adopts the following technical solutions:

[0007] A positioning structure for intermediate shaft gear of double intermediate shaft gearbox, comprising intermediate shaft, intermediate shaft gear is sleeved on the intermediate shaft, the assembly of the intermediate shaft and the intermediate shaft gear is provided with stepped hole, and cylindrical pin is arranged in the stepped hole.

[0008] The stepped hole comprises first cylinder segment and second cylinder segment with different hole diameters, the first cylinder segment is located on the intermediate shaft gear, the first section of the second cylinder segment is located on the intermediate shaft gear, and the second section of the second cylinder segment is located on the intermediate shaft.

[0009] The utility model also comprises the following technical features:

[0010] The intermediate shaft gear comprises ring segment and gear segment.

[0011] The stepped hole located on the intermediate shaft gear is arranged on the ring segment.

[0012] The length ratio of the first section and the second section of the second cylinder segment is 1:2.

[0013] The diameter of the first cylindrical section is 5mm larger than the diameter of the second cylindrical section.

[0014] The diameter of the second cylindrical section is equal to the outer diameter of the cylindrical pin.

[0015] One third of the cylindrical pin is located in the first cylindrical section, and two thirds of the cylindrical pin is located in the second cylindrical section.

[0016] The joint of the first cylindrical section and the second cylindrical section is provided with a conical riveting surface.

[0017] Compared with the prior art, the utility model has the beneficial technical effects that:

[0018] (I) The intermediate shaft gear of the present application does not need to process a rectangular key groove through the whole gear width, a stepped hole is formed on the intermediate shaft gear and the intermediate shaft, the stepped hole is a structural mutation in the diameter direction, there is no stress concentration point for transmitting torque, the torque bearing capacity is strong, the stress concentration point at the chamfered root of the gear key groove is eliminated, the gear strength is improved, the intermediate shaft gear is prevented from being broken at the root of the key groove when transmitting large torque, and the technical problem that the key connection between the intermediate shaft gears in the prior art easily causes the intermediate shaft gears to be broken is solved.

[0019] (II) In the utility model, the gear and the spacer sleeve of the intermediate shaft gear in the prior art are made into an integrated intermediate shaft gear, the intermediate shaft gear width of the integrated intermediate shaft gear is greater than the original intermediate shaft gear width, the contact area of the intermediate shaft and the intermediate shaft gear is increased, and the torque that can be transmitted after the intermediate shaft gear is assembled with the intermediate shaft is proportional to the contact area of the intermediate shaft and the intermediate shaft gear, therefore, the torque that can be transmitted is also improved. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0021] Figure 2 It is Figure 1 A partial enlarged view;

[0022] Figure 3 It is a schematic diagram of the structure of the intermediate shaft gear in the utility model.

[0023] The meanings of the various reference numerals in the drawing are as follows: 1-intermediate shaft, 2-intermediate shaft gear, 3-stepped hole, 4-cylindrical pin, 5-riveting surface;

[0024] 201-circular ring section, 202-gear section;

[0025] 301-first cylindrical section, 302-second cylindrical section.

[0026] The specific content of the utility model will be further explained and described in detail in combination with the embodiments below. DETAILED DESCRIPTION

[0027] It should be noted that all the components in the utility model, in the absence of special instructions, adopt the components known in the art.

[0028] The specific embodiments of the utility model are given below, and it should be noted that the utility model is not limited to the following specific embodiments, and any equivalent variations made on the basis of the technical solutions of the application fall within the protection scope of the utility model.

[0029] The utility model gives a kind of positioning structure for the intermediate shaft gear of double intermediate shaft gearbox intermediate shaft, including intermediate shaft 1, intermediate shaft 1 is equipped with intermediate shaft gear 2, the assembly of intermediate shaft 1 and intermediate shaft gear 2 is equipped with stepped hole 3, and stepped hole 3 is provided with cylindrical pin 4;

[0030] Stepped hole 3 includes the first cylinder section 301 and the second cylinder section 302 of different hole diameters, and the first cylinder section 301 is located on the intermediate shaft gear 2, and the first section of the second cylinder section 302 is located on the intermediate shaft gear 2, and the second section of the second cylinder section 302 is located on the intermediate shaft 1.

[0031] In the above technical scheme, the intermediate shaft gear in the present application does not need to process the rectangular key groove through the entire gear width, and the stepped hole is opened on the intermediate shaft gear and the intermediate shaft, which is a structural mutation in the diameter direction, and there is no stress concentration point for transmitting torque, and the torque bearing capacity is strong, the stress concentration point at the chamfered root of the gear key groove is eliminated, the gear strength is improved, the intermediate shaft gear is avoided from being broken at the root of the key groove when transmitting large torque, and the technical problem that the key connection between the intermediate shaft gears in the prior art easily leads to the breakage of the intermediate shaft gears is solved.

[0032] The intermediate shaft gear 2 includes a circular ring section 201 and a gear section 202.

[0033] In the above technical scheme, the circular ring section 201 plays the role of spacer sleeve, and the gear and spacer sleeve of the original mechanism are made into an integrated structure, the axial position of the intermediate shaft gear 2 is limited, and the number of parts is also reduced, and the assembly is simpler.

[0034] The gear and spacer sleeve of the intermediate shaft gear in the prior art are made into an integrated intermediate shaft gear, the intermediate shaft gear width of the integrated intermediate shaft gear is greater than the original intermediate shaft gear width, the contact area of the intermediate shaft and the intermediate shaft gear is increased, and the torque that can be transmitted after the assembly of the intermediate shaft gear and the intermediate shaft is proportional to the contact area of the intermediate shaft and the intermediate shaft gear, so the torque that can be transmitted is also improved.

[0035] The stepped hole 3 on the intermediate shaft gear 2 is arranged on the circular ring segment 201.

[0036] In the above technical solution, the circular ring segment of the intermediate shaft gear is used to set the cylindrical pin hole, so as to avoid the stress affecting the gear segment 202.

[0037] The length ratio of the first segment and the second segment of the second cylindrical segment 302 is 1:2.

[0038] In the above technical solution, the intermediate shaft gear 2 needs to reduce the moment of inertia and weight as much as possible, and the wall thickness of the intermediate shaft gear circular ring segment needs to be reduced as much as possible. The length of the first cylindrical segment 301 and the length of the first segment of the second cylindrical segment 302 need to be as short as possible. However, if the length of the first segment of the second cylindrical segment 302 is too short, it cannot play the positioning role of the intermediate shaft gear 2. Considering the weight reduction of the intermediate shaft gear 3 and the firm positioning of the gear, the length ratio of the first segment and the second segment of the second cylindrical segment 302 is designed to be 1:2, which is the best.

[0039] The diameter of the first cylindrical segment 301 is 5mm larger than the diameter of the second cylindrical segment 302.

[0040] In the above technical solution, the single-side edge radius is 2.5mm in the radial direction. The 2.5mm is used to leave enough space for the riveting impact surface. If the riveting impact surface is too small, it will be difficult for the riveting tool to align the riveting point. If the riveting impact surface is too large, the required riveting force will be too large or it will be difficult to produce enough plastic deformation.

[0041] The diameter of the second cylindrical segment 302 is equal to the outer diameter of the cylindrical pin 4.

[0042] In the above technical solution, the second cylindrical segment 302 is used to install the cylindrical pin 4, and the basic dimensions are the same, and the tolerance is a transition fit, which facilitates the installation of the cylindrical pin 4.

[0043] One third of the cylindrical pin 4 is located in the first cylindrical segment 301, and two thirds of the cylindrical pin 4 is located in the second cylindrical segment 302.

[0044] In the above technical solution, the intermediate shaft gear 2 needs to reduce the moment of inertia and weight as much as possible, and the wall thickness of the intermediate shaft gear circular ring segment needs to be reduced as much as possible. The length of the first cylindrical segment 301 and the length of the first segment of the second cylindrical segment 302 need to be as short as possible. However, if the length of the first segment of the second cylindrical segment 302 is too short, it cannot play the positioning role of the intermediate shaft gear 2. Therefore, it is set in this way.

[0045] The connection between the first cylindrical segment 301 and the second cylindrical segment 302 is provided with a conical riveting impact surface 5.

[0046] In the above technical solution, the riveting surface 5 produces plastic deformation to fix the cylindrical pin 4 and prevent the cylindrical pin 4 from being pulled out of the stepped hole 3. The relative position between the intermediate shaft gear 2 and the intermediate shaft 1 is ensured by the cylindrical pin 4 during normal operation of the gearbox.

Claims

1. A positioning structure for a countershaft gear of a double countershaft transmission countershaft, comprising a countershaft (1) on which a countershaft gear (2) is fitted, characterized in that, The assembly of the intermediate shaft (1) and the intermediate shaft gear (2) is provided with a stepped hole (3), and a cylindrical pin (4) is arranged in the stepped hole (3). The stepped hole (3) comprises a first cylindrical section (301) and a second cylindrical section (302) with different hole diameters, the first cylindrical section (301) is located on the intermediate shaft gear (2), and the first section of the second cylindrical section (302) is located on the intermediate shaft gear (2), and the second section of the second cylindrical section (302) is located on the intermediate shaft (1).

2. The positioning structure for the intermediate shaft gear of the double intermediate shaft transmission according to claim 1, wherein The intermediate shaft gear (2) comprises a ring section (201) and a gear section (202).

3. The positioning structure for the intermediate shaft gear of the double intermediate shaft transmission according to claim 2, wherein The stepped hole (3) located on the intermediate shaft gear (2) is arranged on the ring section (201).

4. The positioning structure for the intermediate shaft gear of the double intermediate shaft transmission according to claim 1, wherein The length ratio of the first section and the second section of the second cylindrical section (302) is 1:

2.

5. The positioning structure for the intermediate shaft gear of the double intermediate shaft transmission according to claim 1, wherein The diameter of the first cylindrical section (301) is 5mm larger than the diameter of the second cylindrical section (302).

6. The positioning structure for the intermediate shaft gear of the double intermediate shaft transmission according to claim 1, wherein The diameter of the second cylindrical section (302) is equal to the outer diameter of the cylindrical pin (4).

7. The positioning structure for the intermediate shaft gears of a double-intermediate shaft transmission according to claim 1, wherein One third of the cylindrical pin (4) is located in the first cylindrical section (301), and two thirds of the cylindrical pin (4) is located in the second cylindrical section (302).

8. The positioning structure for the intermediate shaft gear of the double intermediate shaft transmission according to claim 1, wherein A conical riveting surface (5) is arranged at the joint of the first cylindrical section (301) and the second cylindrical section (302).

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