Device and method for measuring axial clearance of transmission shaft

Abstract

The invention discloses a transmission shaft axial clearance measurement device and method, and belongs to the technical field of diesel outboard engine underwater propulsion system transmission shaft detection, and the device comprises a measurement installation seat, a fixing assembly used for fixing the measurement installation seat, a measurement assembly used for detecting clearance data, and a locking assembly used for locking the measurement assembly. Wherein the measuring mounting seat is provided with a connecting hole position matched with a reduction gearbox assembly mounting structure and a mounting hole position for mounting the measuring assembly; the measuring assembly comprises a measuring meter and a measuring extension probe, the measuring extension probe penetrates through the mounting hole and is used for abutting against the thrust surface of the transmission shaft, and the measuring meter makes contact with the end, away from the transmission shaft, of the measuring extension probe; the locking assembly is connected with the measurement mounting seat and is used for fixing the position of the measurement meter; and the measurement mounting seat is fixedly connected with the reduction gearbox assembly through a fixing assembly. According to the invention, the problems of large measurement error, tedious operation, poor data consistency and the like of a traditional measurement method can be solved.

Description

Technical Field

[0001] This invention relates to the field of transmission shaft testing technology for diesel outboard motor underwater propulsion systems, and in particular to a device and method for measuring the axial clearance of a transmission shaft. Background Technology

[0002] Speedboats and unmanned surface vessels occupy an important position in both military and civilian fields due to their advantages of high speed and maneuverability, lightness and flexibility, safety and reliability, and ease of operation.

[0003] As the core power unit of speedboats and unmanned surface vessels (USVs), the operational stability of the diesel outboard motor's underwater propulsion system directly determines the overall performance of the vessel. The driveshaft is a crucial component in this system, connecting the diesel engine crankshaft's power output to the propeller's propulsion. Its axial clearance directly affects the continuous transmission of power from the engine crankshaft and the stability of the propeller's propulsion. Excessive clearance can lead to transmission shock and accelerated gear wear, while insufficient clearance may cause component jamming, overheating, and damage. Therefore, precise measurement and control of the driveshaft's axial clearance is a critical step in ensuring the reliable operation of the diesel outboard motor and the entire vessel.

[0004] Currently, traditional methods for measuring the axial clearance of drive shafts mainly rely on a combination of a dial indicator and a platform with shims. The specific operating procedure is as follows: the dial indicator is fixed to the platform with a magnetic stand, ensuring the dial indicator probe contacts the corresponding measurement position on the drive shaft. Then, the drive shaft is pulled axially, and the axial clearance value is indirectly obtained by observing the difference in the dial indicator pointer's swing. The core components of this measuring device include a dial indicator, a magnetic stand, a platform with shims, a measuring platform, and the drive shaft and gearbox assembly to be measured. During measurement, the gearbox assembly is placed on the platform, with the platform with shims serving as the supporting carrier for the magnetic stand, stacked on top of the platform.

[0005] Traditional measurement methods have significant drawbacks, the core issue being the inconsistency between the measurement reference and the installation reference of the component being measured. The dial indicator is not directly mounted on the gearbox assembly containing the drive shaft, but rather fixed to a separate shim platform and measurement platform. The drive shaft of a diesel outboard motor is a slender shaft with relatively weak rigidity, making the shim platform and measurement platform susceptible to external environmental influences. Even slight external vibrations can be transmitted to the dial indicator through the platform, causing a shift in the relative position of the dial indicator probe and the drive shaft measurement position, resulting in significant measurement errors. Furthermore, traditional measurement methods require repeated adjustments to the dial indicator's installation and positioning, making the process cumbersome. The accuracy of the measurement results is highly dependent on the operator's experience, leading to significant variations in results from different operators. This makes it difficult to guarantee the consistency and reliability of the measurement data, failing to meet the high-precision measurement requirements of diesel outboard motor underwater propulsion systems for the axial clearance of the drive shaft. Summary of the Invention

[0006] To address the problems of large measurement errors, cumbersome operation, and poor data consistency inherent in traditional measurement methods, this invention provides a device and method for measuring the axial clearance of a driveshaft. By utilizing existing structures such as the gearbox housing, bearing housing mounting holes, and driveshaft thrust surface, the measuring components are directly mounted on the gearbox assembly, ensuring that the measurement reference is consistent with the driveshaft axial clearance adjustment reference. This fundamentally reduces the impact of external vibrations on the measurement results and significantly improves measurement accuracy. Simultaneously, the optimized device structure design simplifies the operation process, reduces reliance on operator experience, and enables rapid, accurate, and stable measurement of the driveshaft axial clearance, providing reliable technical support for the assembly, debugging, and maintenance of diesel outboard motor underwater propulsion systems.

[0007] The technical solution adopted by the present invention, a device and method for measuring axial clearance of a transmission shaft, is as follows: A drive shaft axial clearance measuring device includes a measuring mounting base adapted to and connected to a diesel outboard motor gearbox assembly, a fixing component for fixing the measuring mounting base, a measuring component for detecting clearance data, and a locking component for locking the measuring component; wherein the measuring mounting base has connection holes adapted to the gearbox assembly mounting structure and mounting holes for mounting the measuring component.

[0008] The measuring assembly includes a measuring gauge and a measuring extension probe. The measuring extension probe passes through a mounting hole and is used to abut against the thrust surface of the thrust bearing. The measuring gauge contacts the end of the measuring extension probe away from the thrust bearing. The locking assembly is connected to the measuring mounting base and is used to fix the position of the measuring gauge. The measuring mounting base is fixedly connected to the gearbox assembly via a fixing assembly.

[0009] A further improvement of the technical solution of the present invention is that: the connection hole of the measuring mounting base includes a mounting fixing hole, a transmission shaft hole and a thrust bearing hole; wherein, the mounting fixing hole is aligned with the preset mounting hole of the gearbox assembly, the transmission shaft hole is for the transmission shaft to pass through, and the thrust bearing hole is adapted to the thrust bearing of the transmission shaft.

[0010] A further improvement of the technical solution of the present invention is that: the fixing component includes a fixing bolt and a sealing ring; wherein, the fixing bolt passes through the mounting hole and locks the measuring mounting seat to the gearbox assembly.

[0011] A further improvement of the technical solution of the present invention is that: the mounting hole of the measuring mounting base includes a measuring instrument mounting hole, the axis of the measuring instrument mounting hole is parallel to the axis of the transmission shaft, and the measuring extension probe can move along the axis of the measuring instrument mounting hole.

[0012] A further improvement of the technical solution of the present invention is that: the locking assembly includes a locking bolt, the measuring mounting base has a locking bolt hole communicating with the measuring instrument mounting hole, and the locking bolt is screwed into the locking bolt hole and abuts against the outer wall of the measuring instrument.

[0013] A method for measuring the axial clearance of a drive shaft, using the aforementioned measuring device, includes the following steps: S1. Install the thrust bearing to the preset thrust position of the drive shaft; S2. Place the measuring mounting base against the corresponding mounting surface of the gearbox assembly, align the mounting holes with the preset mounting holes of the gearbox assembly, insert the fixing bolts and tighten them to fix the measuring mounting base and the gearbox assembly as one unit. S3. Insert the measuring extension probe along the measuring instrument mounting hole until the measuring extension probe makes stable contact with the thrust surface of the thrust bearing; S4. Insert the measuring instrument into the measuring instrument mounting hole, adjust the position of the measuring instrument so that the probe of the measuring instrument is in full contact with the end of the measuring extension probe away from the thrust bearing, observe the swing of the measuring instrument pointer, and after the pointer stabilizes in the middle area of ​​the range, screw in the locking bolt to lock and fix the measuring instrument. S5. The operator holds the splined end of the drive shaft with both hands and slowly and steadily pulls the drive shaft back and forth along the axis to ensure that the drive shaft moves smoothly without jamming. At the same time, observe the swing change of the measuring instrument pointer and record the maximum difference of the pointer swing. This difference is the axial clearance value of the drive shaft when the adjusting shim is not installed. S6. Based on the axial clearance value measured in step S5, select an adjustment shim of the corresponding thickness for installation. Repeat steps S3-S5 until the axial clearance value of the drive shaft meets the design requirements.

[0014] A further improvement of the technical solution of the present invention is that: in step S5, the force of pulling the transmission shaft is controlled at 5-10N, and the axis of the transmission shaft is kept parallel to the axis of the measuring instrument mounting hole during the pulling process to avoid radial displacement of the transmission shaft.

[0015] The technological advancements achieved by this invention due to the adoption of the above technical solutions are as follows: This invention directly and fixedly connects the measuring mounting base to the gearbox assembly, ensuring that the measuring reference is consistent with the axial clearance adjustment reference of the drive shaft. This completely eliminates the interference of platform vibration in traditional measurement methods, and the measurement error is controlled within ±0.01mm, which can meet the high-precision measurement requirements of diesel outboard motor underwater propulsion systems for the axial clearance of slender shafts.

[0016] Traditional measurement methods require significant time for platform debugging and dial indicator positioning. This invention, however, requires only five core steps to complete the measurement, thus shortening the time required for a single measurement and improving the efficiency of measurement operations. Furthermore, the device's operation is simple and straightforward, reducing reliance on operator experience and allowing different operators to obtain highly consistent measurement data. Attached Figure Description

[0017] Figure 1This is a schematic diagram of the structure of the drive shaft axial clearance measuring device and the gearbox assembly according to the present invention. Figure 2 This is a schematic diagram of the structure of a transmission shaft axial clearance measuring device according to the present invention; Figure 3 This is a schematic diagram of the structure of the measuring mounting base of the axial clearance measuring device for a transmission shaft according to the present invention.

[0018] In the attached diagram: 1. Measuring mounting base; 11. Mounting hole; 12. Mounting fixing hole; 13. Drive shaft hole; 14. Thrust bearing hole; 15. Locking bolt hole; 2. Fixing bolts; 3. Sealing rings; 4. Locking bolts; 5. Measuring gauges; 6. Measuring extension probes; 7. Drive shaft; 8. Gearbox assembly; 9. Thrust bearing. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings. In the following description, descriptions of formula structures and techniques are omitted to avoid unnecessarily obscuring the concepts of this invention. Example 1

[0020] like Figure 1-3 As shown in the figure, this embodiment discloses a transmission shaft axial clearance measuring device, including a measuring mounting base 1, a fixing component, a measuring component, and a locking component.

[0021] In this embodiment, the measuring mounting base 1 has connection holes and mounting holes 11. The connection holes include mounting and fixing holes 12, drive shaft holes 13, and thrust bearing holes 14. The mounting and fixing holes 12 correspond one-to-one with the preset mounting holes of the gearbox assembly 8 and are used to pass through fixing bolts 2. The inner diameter of the drive shaft hole 13 is slightly larger than the outer diameter of the drive shaft 7, allowing the drive shaft 7 to pass through without affecting the axial movement of the drive shaft 7. The size of the thrust bearing hole 14 is adapted to the outer diameter of the thrust bearing and is used to position the thrust bearing. The mounting hole 11 is the mounting hole for the measuring gauge 5, and its axis is parallel to the axis of the drive shaft 7, with a coaxiality error of no more than 0.01 mm.

[0022] In this embodiment, the fixing components include fixing bolts 2 and sealing rings 3. The fixing bolts 2 pass through the mounting holes 12 and lock the measuring mounting base 1 to the gearbox assembly 8, so that the measuring mounting base 1 and the gearbox assembly 8 form a whole, ensuring that the measuring reference is consistent with the axial clearance adjustment reference of the transmission shaft 7.

[0023] In this embodiment, the measuring components include a measuring gauge 5 and a measuring extension probe 6. The measuring gauge 5 is selected as a dial indicator or a micrometer.

[0024] In this embodiment, the locking component is a locking bolt 4, and the measuring mounting base 1 has a locking bolt hole 15 that communicates with the mounting hole of the measuring instrument 5. After the measuring instrument 5 is adjusted to a suitable position, the locking bolt 4 is screwed in, and the end of the locking bolt 4 abuts against the outer wall of the measuring instrument 5, fixing the measuring instrument 5 in the mounting hole of the measuring instrument 5, preventing the measuring instrument 5 from shifting during the measurement process, and ensuring the stability of the measurement data. Example 2

[0025] This embodiment provides a method for measuring the axial clearance of a drive shaft, including the following steps: S1. Thrust bearing installation: Accurately install the thrust bearing to the preset thrust position of the drive shaft 7. During the installation process, ensure that the end face of the thrust bearing is perpendicular to the axis of the drive shaft 7. The fit clearance between the thrust bearing and the drive shaft 7 meets the assembly technical requirements of the diesel outboard motor underwater propulsion system. Avoid the impact of subsequent clearance measurement due to the misalignment of the thrust bearing installation.

[0026] S2. Fixing the measuring mounting base 1: Place the measuring mounting base 1 against the corresponding mounting surface of the gearbox assembly 8, aligning the mounting holes 12 of the measuring mounting base 1 with the preset mounting holes of the gearbox assembly 8. Then, insert the fixing bolts 2 into the mounting holes 12 and use a torque wrench to evenly tighten the fixing bolts 2, controlling the tightening torque within the preset range, so that the measuring mounting base 1 and the gearbox assembly 8 are fixed together, ensuring that the measuring mounting base 1 is not loose or misaligned.

[0027] S3. Installation of the Measurement Extension Probe 6: Slowly insert the measurement extension probe 6 along the mounting hole of the measuring gauge 5, keeping the probe's axis parallel to the axis of the mounting hole of the measuring gauge 5 during insertion, until the measurement extension probe 6 makes stable contact with the thrust surface of the thrust bearing 9. Avoid applying excessive force during contact to prevent damage to the probe or the thrust surface of the thrust bearing 9.

[0028] S4. Installation and Adjustment of Measuring Gauge 5: Insert measuring gauge 5 into the mounting hole and gently adjust its position so that the probe of measuring gauge 5 is in full contact with the end of the measuring extension probe 6 furthest from the thrust bearing 9. Observe the swing of the measuring gauge 5 pointer. Once the pointer stabilizes in the middle range, screw in the locking bolt 4 to lock and secure the measuring gauge 5. Adjusting the pointer to the middle range facilitates observation of the positive and negative displacement changes of the drive shaft 7 and prevents the pointer from exceeding the range.

[0029] S5. Axial Clearance Measurement: The operator holds the splined end of the drive shaft 7 with both hands and slowly and steadily pulls the drive shaft 7 back and forth along the axial direction. The pulling force should be controlled at 5-10N. During the pulling process, keep the axis of the drive shaft 7 parallel to the axis of the mounting hole of the measuring gauge 5 to avoid radial displacement of the drive shaft 7. Ensure that the drive shaft 7 moves smoothly without jamming, and simultaneously observe the swing change of the pointer of the measuring gauge 5. Record the maximum difference in pointer swing. This difference is the axial clearance value of the drive shaft 7 without the adjustment shim installed.

[0030] S6. Installation and Re-measurement of Adjusting Shims: Based on the measured axial clearance value, consult the design documents of the diesel outboard motor underwater propulsion system and select adjusting shims of the corresponding thickness for installation. After the adjusting shims are installed, repeat the steps of installing the extended measuring probe 6, installing and adjusting the measuring table 5, and measuring the axial clearance until the axial clearance value of the drive shaft 7 meets the design requirements.

[0031] In the above embodiments, a device and method for measuring the axial clearance of a drive shaft are provided. This invention directly and fixedly connects the measuring mounting base to the gearbox assembly, ensuring that the measuring reference is consistent with the installation reference of the drive shaft. This completely eliminates the interference of platform vibration in traditional measurement methods, controlling the measurement error within ±0.01mm. This meets the high-precision measurement requirements of diesel outboard motor underwater propulsion systems for the axial clearance of slender shafts. Traditional measurement methods require significant time for platform debugging and dial indicator positioning; this invention requires only five core steps to complete the measurement, thus shortening the single measurement time and improving the efficiency of measurement operations. Furthermore, the device's operation process is simple and clear, reducing reliance on operator experience, and allowing different operators to obtain highly consistent measurement data.

[0032] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the concept and scope of the present invention. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the inventive concept should fall within the protection scope of the present invention. All technical contents for which protection is sought in this invention are fully described in the claims.

Claims

1. A device for measuring the axial clearance of a transmission shaft, characterized in that: It includes a measuring mounting base (1) adapted to the diesel outboard motor gearbox assembly (8), a fixing component for fixing the measuring mounting base (1), a measuring component for detecting clearance data, and a locking component for locking the measuring component; wherein the measuring mounting base (1) is provided with a connection hole adapted to the mounting structure of the gearbox assembly (8) and a mounting hole (11) for installing the measuring component. The measuring assembly includes a measuring gauge (5) and a measuring extension probe (6). The measuring extension probe (6) passes through the mounting hole (11) and is used to abut against the thrust surface of the thrust bearing (9). The measuring gauge (5) and the measuring extension probe (6) are in contact with the end away from the thrust bearing (9). The locking assembly is connected to the measuring mounting base (1) and is used to fix the position of the measuring gauge (5). The measuring mounting base (1) is fixedly connected to the gearbox assembly (8) through the fixing assembly.

2. The axial clearance measuring device for a transmission shaft according to claim 1, characterized in that: The connection holes of the measuring mounting base (1) include a mounting fixing hole (12), a transmission shaft hole (13), and a thrust bearing hole (14); wherein, the mounting fixing hole (12) is aligned with the preset mounting hole of the gearbox assembly (8), the transmission shaft hole (13) is for the transmission shaft (7) to pass through, and the thrust bearing hole (14) is adapted to the thrust bearing (9) of the transmission shaft.

3. The axial clearance measuring device for a transmission shaft according to claim 2, characterized in that: The fixing component includes a fixing bolt (2) and a sealing ring (3); wherein the fixing bolt (2) passes through the mounting fixing hole (12) and locks the measuring mounting seat (1) to the gearbox assembly (8).

4. The axial clearance measuring device for a transmission shaft according to claim 1, characterized in that: The mounting hole (11) of the measuring mounting base (1) includes a measuring gauge (5) mounting hole. The axis of the measuring gauge (5) mounting hole is parallel to the axis of the transmission shaft (7). The measuring extension probe (6) can move along the axis of the measuring gauge (5) mounting hole.

5. The axial clearance measuring device for a transmission shaft according to claim 1, characterized in that: The locking assembly includes a locking bolt (4), and the measuring mounting base (1) has a locking bolt hole (15) that communicates with the mounting hole of the measuring instrument (5). The locking bolt (4) is screwed into the locking bolt hole (15) and abuts against the outer wall of the measuring instrument (5).

6. A method for measuring the axial clearance of a transmission shaft, characterized in that, Using the measuring device according to any one of claims 1-5, the steps include: S1. Install the thrust bearing (9) to the preset thrust position of the drive shaft (7); S2. Place the measuring mounting base (1) against the corresponding mounting surface of the gearbox assembly (8), align the mounting fixing hole (12) with the preset mounting hole of the gearbox assembly (8), insert the fixing bolt (2) and tighten it, so that the measuring mounting base (1) and the gearbox assembly (8) are fixed together. S3. Insert the measuring extension probe (6) along the mounting hole of the measuring table (5) until the measuring extension probe (6) is in stable contact with the thrust surface of the thrust bearing (9); S4. Insert the measuring instrument (5) into the mounting hole of the measuring instrument (5), adjust the position of the measuring instrument (5) so that the probe of the measuring instrument (5) is in full contact with the end of the measuring extension probe (6) away from the thrust bearing (9), observe the swing of the pointer of the measuring instrument (5), and after the pointer stabilizes in the middle range, screw in the locking bolt (4) to lock and fix the measuring instrument (5). S5. The operator holds the spline end of the drive shaft (7) with both hands and slowly and steadily pulls the drive shaft (7) back and forth along the axial direction to ensure that the drive shaft (7) moves smoothly without jamming. At the same time, observe the swing change of the pointer of the measuring instrument (5) and record the maximum difference of the pointer swing. This difference is the axial clearance value of the drive shaft (7) when the adjusting shim is not installed. S6. Based on the axial clearance value measured in step S5, select the corresponding thickness of the adjustment shim for installation, and repeat steps S3-S5 until the axial clearance value of the drive shaft (7) meets the design requirements.

7. The method for measuring axial clearance of a transmission shaft according to claim 6, characterized in that: In step S5, the force of pulling the drive shaft (7) is controlled at 5-10N. During the pulling process, the axis of the drive shaft (7) is kept parallel to the axis of the measuring instrument (5) mounting hole to avoid radial displacement of the drive shaft (7).

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