A kind of speed reducer gap adjustment process and speed reducer

Abstract

The application provides a kind of reduction gearbox gap adjustment process, belongs to assembly process technical field.The process includes: bearing is installed in the bearing installation site of support component, gland component is installed on the axial side of support component corresponding bearing, and initial gap is formed between the two;Gland component is driven to move along the axial direction towards bearing, until the inner end surface of gland component and the corresponding end surface of bearing reach the fit reference;The first gap value of the first gap value of the first gap value of the first gap value of the first gap value of the first gap value of the first gap value of the first gap value of the first gap value of the first gap value of the first gap value of the first value is obtained;According to the axial load under the working state of bearing, determine the target gap value that the gland component and the bearing need to keep;According to the difference value of the two, determine the target size of the compensation element, select the corresponding compensation element and set between the gland component and the support component.The application eliminates the influence of box body machining tolerance on gap, compensates the disturbance of helical gear axial force on gap, does not need to try to fit repeatedly, realizes fast and accurate adjustment, improves assembly efficiency and consistency.

Description

Technical Field

[0001] This invention belongs to the field of assembly process technology, and more specifically, it relates to a gearbox clearance adjustment process and a gearbox. Background Technology

[0002] The travel gearbox of drilling rigs mostly uses helical gear transmission, and the axial clearance of its internal bearings has a significant impact on the reliability of the entire machine. If the clearance is too large, it will generate impact and abnormal noise under the axial component force of the helical gear, and accelerate bearing wear; if the clearance is too small or is negative, it will lead to excessive preload of the bearing, resulting in severe heat generation during operation, and even burning out the bearing.

[0003] Currently, shim compensation is commonly used to adjust bearing cover clearance. Operators select shim thickness based on theoretical calculations or experience, and repeatedly test fits to maintain a reasonable clearance between the cover and the bearing outer ring end face. However, when using this method, there are tolerances in the gearbox housing machining dimensions, and the actual dimensions of the bearing mounting hole depth, cover mating surface, etc., deviate from the theoretical values. In addition, the axial component force generated by the helical gear during operation will cause additional axial displacement of the bearing outer ring. After these two factors are combined, the shim thickness selected according to theoretical calculations or experience often deviates from the optimal clearance required by actual working conditions, resulting in low adjustment accuracy, poor consistency, and low efficiency of repeated test fits. Summary of the Invention

[0004] The purpose of this invention is to provide a gearbox clearance adjustment process, which aims to solve the problems in the existing gearbox bearing clearance adjustment process, where the combined influence of gearbox machining tolerance and helical gear axial force leads to low accuracy, poor consistency, and low efficiency of repeated trial fittings due to the reliance on theoretical calculations or experience in shim selection.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is: to provide a gearbox clearance adjustment process, comprising the following steps: S1: Install the bearing in the bearing mounting position of the support member, and install the cover member on the support member on the axial side corresponding to the bearing, so that an initial gap is formed between the cover member and the support member; S2: Drive the gland member to move axially toward the bearing until the inner end face of the gland member and the corresponding end face of the bearing reach the contact reference; S3: Obtain the first gap value between the gland member and the support member under the fitting reference; S4: Determine the target clearance value that needs to be maintained between the gland member and the bearing based on the axial load experienced by the bearing in the working state; S5: Determine the target size of the compensation element based on the difference between the first gap value and the target gap value, and select the compensation element of the corresponding size to be placed between the cover member and the support member, so as to maintain the target gap between the inner end face of the cover member and the corresponding end face of the bearing in the final tightened state.

[0006] In one possible implementation, the specific method for driving the gland member to move to the fitting reference in step S2 is as follows: An increasing axial preload is applied to the gland component by a tightening device, and the relationship curve between the preload and the axial displacement of the gland component is collected in real time. When the relationship curve shows a sudden inflection point in the slope that indicates physical contact between the inner end face of the gland component and the corresponding end face of the bearing, it is determined that the fitting reference has been reached and the drive is stopped.

[0007] In one possible implementation, in step S2, when identifying the inflection point of the slope abrupt change, the linear segment force-displacement data before contact and the nonlinear segment force-displacement data after contact are fitted and extrapolated respectively. The intersection of the two fitted curves is determined as the theoretical fitting point, and the theoretical fitting point is used as the fitting reference.

[0008] In one possible implementation, between step S2 and step S3, the following is also included: The pressure-holding device maintains the current axial position of the gland member to prevent axial rebound of the gland member before measurement, and then performs the gap measurement operation in step S3.

[0009] In one possible implementation, between step S3 and step S4, the following is also included: A preload simulating the axial load under the working state is applied to the bearing along the bearing axis, and the gap value between the cover member and the support member is remeasured under the preload state. The remeasured gap value is used as the updated first gap value to participate in the calculation of subsequent steps S4 and S5.

[0010] In one possible implementation, step S4, determining the target clearance value based on the axial load experienced by the bearing during operation, includes: Obtain the helical parameters and transmitted torque of the rotary transmission component inside the gearbox, and calculate the axial component force acting on the bearing; By combining the axial stiffness characteristics of the bearing, the displacement of the corresponding end face of the bearing under the action of the axial component force is obtained. The target gap value is obtained by superimposing the preset lubrication and thermal expansion compensation amounts.

[0011] In one possible implementation, in step S4, the calculation of the target gap value is automatically completed by the mechanical model built into the assembly control system. After the operator inputs the helical parameters and torque parameters of the rotary transmission component, the system automatically outputs the target gap value and generates the size instruction of the compensation element.

[0012] In one possible implementation, in step S5, when determining the target size of the compensation element, the elastic deformation of the gland member under the final tightening state due to the tightening torque is also introduced as a correction factor to compensate and correct the difference between the first gap value and the target gap value.

[0013] In one possible implementation, in step S5, when determining the target size of the compensation element, the actual total axial displacement Lactual of the pressure cap member during the period from the start of movement to reaching the fitting reference in step S2 is obtained, and the actual total axial displacement Lactual is compared with the theoretical total axial displacement Ltheoretical, and a displacement deviation compensation amount ΔL is generated based on the comparison result. The difference between the first gap value and the target gap value is used as the base shim thickness, and then the displacement deviation compensation amount ΔL is added to obtain the target size of the compensation element.

[0014] The beneficial effects of the gearbox clearance adjustment process provided by this invention are as follows: Compared with the prior art, this invention first drives the gland component to fit against the bearing end face without shims, obtaining the actual clearance value between the gland component and the support component in the fitted state. This measured value fully reflects the true clearance state accumulated by factors such as gearbox machining tolerances and bearing dimensional deviations in the current assembly. Based on this, a target clearance value is determined separately according to the axial load under bearing operating conditions, ensuring that the target clearance setting accurately matches the actual working requirements. Finally, the size of the required compensation element is directly calculated based on the difference between the measured value and the target value, allowing adjustment to be completed in a single selection.

[0015] The aforementioned technical solution, on the one hand, replaces theoretical estimation with individual measured data, eliminating the adverse effects of gearbox machining tolerances on clearance accuracy; on the other hand, it incorporates the axial component force generated by the helical gear as an independent variable into the target clearance determination process, avoiding disturbances to the clearance state caused by the axial component force. The entire adjustment process does not require repeated trial fittings based on operator experience; the thickness of the compensation element is uniquely determined by the difference between the measured data and the target value, achieving a one-step solution. While ensuring that the clearance of each gearbox accurately matches its actual size, it also improves assembly efficiency and product consistency.

[0016] The present invention also provides a gearbox, which is assembled using the aforementioned gearbox clearance adjustment process.

[0017] The beneficial effects of the gearbox provided by this invention are as follows: Compared with the prior art, this gearbox is assembled using the above-mentioned clearance adjustment process. The free clearance between the bearing cap and the bearing outer ring end face is precisely matched with the actual size of the gearbox and the working load of the helical gear, eliminating the influence of the accumulation of housing machining tolerances on clearance accuracy. The clearance consistency between each gearbox is high, the bearings are in the optimal working clearance state, there is no axial movement impact during operation, bearing wear is reduced, service life is extended, and the overall machine operating noise and temperature rise are improved. At the same time, this process can be standardized and automated, ensuring stable and reliable assembly quality of each gearbox in mass production. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a flowchart of a gearbox clearance adjustment process provided in an embodiment of the present invention. Detailed Implementation

[0020] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0021] Unless otherwise explicitly specified, the use of terms such as "first," "second," or "third" is intended to distinguish different objects, not to describe a specific order.

[0022] Unless otherwise expressly defined, the use of directional terms such as “center,” “lateral,” “longitudinal,” “horizontal,” “vertical,” “top,” “bottom,” “inner,” “outer,” “upper,” “lower,” “front,” “rear,” “left,” “right,” “clockwise,” “counterclockwise,” “high,” and “low” to indicate orientation or positional relationships is based on the orientation and positional relationships shown in the accompanying drawings and is only for the convenience of describing the invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the specific scope of protection of the invention.

[0023] Please see Figure 1This invention provides a gearbox clearance adjustment process. This gearbox clearance adjustment process is mainly applied to the bearing assembly stage of the traveling gearbox of an engineering drilling rig. It controls the axial clearance between the bearing and the pressure cap component, solving problems such as insufficient clearance control accuracy, low assembly efficiency, and poor product consistency caused by accumulated machining tolerances of support components and interference from the axial force of helical gears in traditional assembly methods. This process, through a holistic approach of quantifying the fitting benchmark, measuring clearance compensation, and designing clearance based on operating conditions, achieves rapid adjustment of bearing clearance, improves the operational reliability and assembly efficiency of the gearbox, and possesses good versatility, extending its application to bearing clearance adjustment operations in various industrial gearboxes and engineering machinery transmission boxes that use helical gear transmissions.

[0024] Step S1 is the initial step of the adjustment process of the present invention. Its purpose is to complete the initial installation of the bearing and the cover component, and to form an initial gap between the cover component and the support component that can be subsequently measured and compensated.

[0025] In practice, the bearing to be assembled is first inserted into the bearing mounting hole of the support component. The bearing can be installed by cold pressing, hot pressing, or hammering, depending on the type, size, and material of the bearing and the support component.

[0026] For tapered roller bearings or cylindrical roller bearings commonly used in the travel gearbox of drilling rigs, cold press fitting is preferred. This means using press fitting equipment to smoothly press the bearing into the bearing mounting hole, ensuring that the outer ring of the bearing and the mounting hole have a proper interference fit.

[0027] After the bearing is installed, the end face of the bearing outer ring used for axial positioning should face outwards to facilitate subsequent contact with the inner end face of the gland component. After the bearing is installed, install the gland component on the support component on the axial side corresponding to the bearing.

[0028] The gland component is usually a disc-shaped or flange-shaped structure with several through holes on its outer periphery for fastening bolts to pass through, and an inner end face in the center. After the gland component is fastened, the inner end face is opposite to the corresponding end face of the outer ring of the bearing.

[0029] When installing the gland component, no compensating elements are placed between its mating surface and the support component, thus naturally forming an initial gap between the gland component and the support component. The size of this initial gap is determined by the actual dimensions of multiple parts, such as the depth of the bearing mounting hole in the support component, the width of the bearing outer ring, and the height of the stop of the gland component, reflecting the unique dimensional chain state of this gearbox.

[0030] It should be noted that the initial gap in step S1 is relative to the gap between the gland component and the support component after the final adjustment, which is filled by the compensating element. Without the compensating element, the gland component is initially fixed to the support component with a small torque using only fastening bolts. At this point, there may still be a certain distance between the inner end face of the gland component and the outer ring end face of the bearing, or they may already be in contact, depending on the actual dimensions of each part. Whether they are in contact initially or not does not affect the implementation of subsequent steps.

[0031] The purpose of step S2 is to control the gland component to move axially until the inner end face of the gland component and the corresponding end face of the bearing reach the fitting reference.

[0032] In specific implementation, step S2 can use a tightening device to apply an increasing axial preload to the fastening bolts of the gland component, so that the gland component gradually moves axially toward the bearing under the action of the bolt preload.

[0033] The tightening device preferably uses automated tightening equipment, such as an electric tightening gun or a servo tightening system. Such equipment can accurately control the tightening torque and tightening speed, and can output torque and angle data in real time during the tightening process.

[0034] At the same time, a force-displacement monitoring system is used to collect the relationship curve between the preload and the axial displacement of the gland component in real time.

[0035] Force-displacement monitoring systems typically include force sensors and displacement sensors. The force sensor can be positioned between the tightening device and the fastening bolt to detect the axial preload applied to the bolt in real time. The displacement sensor can be positioned between the outer end face of the gland component and the fixed reference surface of the support component to detect the axial displacement of the gland component in real time. The sampling frequencies of both the force and displacement sensors should be sufficiently high to ensure that subtle changes in the preload-displacement curve are captured; the sampling frequency should be no less than 1 kHz.

[0036] During the process of increasing preload, the gland component moves in a non-contact state. At this time, the preload is only used to overcome the frictional resistance between the gland component and the fastening bolt, as well as the initial resistance between the gland component and the support component. The preload increases approximately linearly with the increase of displacement, and the curve slope is small and relatively stable.

[0037] As the inner end face of the pressure cap component gradually approaches and eventually makes physical contact with the corresponding end face of the bearing outer ring, the bearing outer ring is axially limited by the bottom of the bearing mounting hole of the support component. Continuing to apply preload will result in a rigid reaction force from the bearing outer ring. The rate of change of preload with displacement changes, and the slope of the curve suddenly increases, forming an obvious inflection point of slope change.

[0038] When the force-displacement monitoring system detects the inflection point of the slope change, it determines that the inner end face of the gland component and the corresponding end face of the bearing have reached a physical contact state, that is, the fitting reference has been reached. At this time, the drive is stopped immediately and the preload is no longer applied.

[0039] Using this inflection point as the fitting reference, the instantaneous position at which the inner end face of the gland component just contacts the outer end face of the bearing can be accurately determined. This avoids both incomplete fitting due to insufficient preload and bearing damage due to excessive preload.

[0040] As an alternative to step S2, the force-displacement monitoring system can indirectly obtain preload and displacement data by utilizing the torque and angle sensors integrated into the tightening device, instead of setting up separate force and displacement sensors. Electric tightening guns typically have built-in torque sensors and angle encoders. Through calibration, torque values ​​can be converted into axial preload, and angle values ​​into axial displacement. This solution eliminates the need for additional sensor equipment, reducing system complexity and cost.

[0041] After step S2 determines that the fit reference has been reached and stops driving, the pressure cap component may experience a slight axial rebound due to residual stress or the elastic recovery of the fastening bolts before measurement, which may affect the accuracy of the gap measurement in step S3. Therefore, a pressure holding operation is set between step S2 and step S3.

[0042] In practice, once the force-displacement monitoring system detects the inflection point of the slope change and stops driving, the pressure holding device is immediately activated to maintain the current axial position of the pressure cap component and prevent the pressure cap component from axially rebounding before measurement.

[0043] The pressure-holding device can employ a mechanical locking mechanism, such as a wedge locking device or a ratchet locking mechanism, to mechanically lock the axial position of the gland component after it reaches the mating position; it can also employ a hydraulic pressure-holding circuit, which maintains the pressure inside the hydraulic cylinder through a pressure-holding valve in a hydraulic cylinder-driven mode, keeping the gland component in its current position; or it can employ the brake function of a servo motor, which locks the position of the motor rotor through a motor brake in a servo motor-driven mode.

[0044] After the pressure-holding device is activated, the time required to maintain the current position of the gland component should be sufficient to complete the gap measurement operation in step S3. Once the measurement is complete, the pressure-holding state can be released, allowing the gland component to return to its free state for subsequent installation of compensation elements.

[0045] The purpose of step S3 is to obtain the first gap value between the gland member and the support member under the fitting reference, that is, the actual distance between the flange end face of the gland member and the mating surface of the support member when the inner end face of the gland member just contacts the corresponding end face of the bearing.

[0046] In practice, after step S2 is completed and the fitting reference is reached, the gap between the flange end face of the gland component and the mating surface of the support component is measured using a thickness measuring tool.

[0047] Commonly used thickness measurement tools include feeler gauges and depth micrometers. When using a feeler gauge, feeler gauge pieces of different thicknesses are inserted sequentially into the gap between the flange end face of the gland component and the mating surface of the support component until the largest thickness feeler gauge piece is found that fits perfectly; this thickness is the first gap value. When using a depth micrometer, the reference surface of the depth micrometer is placed on the mating surface of the support component, the end of the measuring rod contacts the flange end face of the gland component, and the reading on the depth micrometer is taken; this reading is the first gap value.

[0048] To improve measurement accuracy, measurements can be taken at multiple different locations on the flange end face of the gland component, and the average of the measurements can be used as the first gap value. Since there may be parallelism errors or local deformations between the flange end face of the gland component and the mating surface of the support component, averaging multiple measurements can more accurately reflect the actual size of the gap.

[0049] During measurement, ensure that the measuring tool is perpendicular to the measuring surface to avoid measurement errors caused by tilting. Additionally, clean the flange end face of the gland component and the mating surface of the support component before measurement to remove oil and foreign matter, ensuring the accuracy of the measurement results.

[0050] After measuring the first clearance value in step S3 and before determining the target clearance value in step S4, a simulated loading operation can be added to more realistically reflect the clearance changes of the bearing under working conditions.

[0051] In practice, after measuring the first clearance value in step S3, a preload simulating the axial load under operating conditions is applied to the outer ring of the bearing along the bearing axis using process equipment. The magnitude of this preload is determined based on the axial component force generated by the rotating transmission components inside the gearbox during actual operation.

[0052] For helical gear drives, the magnitude of the axial force depends on the helix angle of the helical gear and the transmitted torque. The theoretical value of the axial force can be pre-calculated based on the design parameters of the helical gear, and then a preload of the same magnitude can be applied using process equipment.

[0053] Under preload, the outer ring of the bearing will undergo a certain axial displacement, and the clearance between the gland member and the support member will change accordingly. At this time, the clearance between the gland member and the support member is measured again, and this remeasured clearance value is used as the updated first clearance value to participate in the calculation of subsequent steps S4 and S5.

[0054] Traditional static measurements cannot reflect the actual clearance state of a bearing under working load. However, simulated loading operations introduce an axial load equivalent to the working state during the measurement process, making the measured clearance value closer to the actual clearance state of the gearbox during actual operation, thereby improving the adjustment accuracy.

[0055] The purpose of step S4 is to determine the target clearance value that the gland component and the bearing need to maintain based on the axial load on the bearing under working conditions.

[0056] In practical implementation, the helical parameters and transmitted torque of the rotating transmission components within the gearbox are first obtained. For helical gear drives, the helical parameters mainly include the helix angle and normal module of the helical gear, while the transmitted torque is the rated torque transmitted by the gearbox under actual operating conditions. According to the force analysis of helical gears, when transmitting torque, helical gears generate an axial component force along the gear axis. The magnitude of this axial component force can be calculated and determined by the following formula: the axial component force is directly proportional to the transmitted torque, inversely proportional to the pitch circle diameter of the helical gear, and directly proportional to the tangent of the helix angle.

[0057] After calculating the axial component force, and combining it with the bearing's axial stiffness characteristics, the displacement of the corresponding end face of the bearing under the action of this axial component force is obtained. The axial stiffness of a bearing refers to the axial force required for the outer ring of the bearing to produce a unit axial displacement relative to the inner ring when the bearing is subjected to an axial load.

[0058] After obtaining the bearing displacement caused by the axial force, the preset lubrication and thermal expansion compensation values ​​are added to obtain the target clearance value.

[0059] Lubrication compensation refers to the minimum thickness of the lubricating oil film required for a bearing under operating conditions to ensure sufficient hydrodynamic lubrication between the bearing friction pairs.

[0060] Thermal expansion compensation refers to the dimensional changes of various parts of the gearbox due to thermal expansion after the operating temperature rises, including the thermal expansion of the bearing outer ring, the thermal expansion of the support components, and the thermal expansion of the pressure cover components.

[0061] As a preferred option, the target gap value ranges from 0.2 mm to 0.3 mm.

[0062] Step S5 is the final step of this adjustment process. Its purpose is to determine the target size of the compensation element based on the difference between the first gap value and the target gap value, and to select the compensation element of the corresponding size to complete the assembly.

[0063] In practice, the difference between the first gap value and the target gap value is first calculated. This difference is the axial dimension that needs to be filled by the compensation element. Since the first gap value measured in step S3 is the actual gap between the gland member and the support member under the contact reference without the compensation element, and the target gap value is the ideal gap that the gland member and the bearing need to maintain under the working state, the difference between the two is exactly equal to the thickness that the compensation element should have.

[0064] After calculating the difference, a compensation element with a thickness equal to the difference is selected. The compensation element is preferably an adjusting shim, which can be made of steel, copper, or composite materials. The thickness can be selected as a standard thickness shim or custom-made according to actual needs. The selected compensation element is placed between the mating surfaces of the gland component and the support component. Then, the gland component is reinstalled and fixed to the support component with fastening bolts. In the final tightened state, the inner end face of the gland component and the corresponding end face of the bearing maintain the target clearance value, preventing impact due to excessive clearance and over-preload of the bearing due to insufficient clearance.

[0065] As a preferred embodiment of step S5, when determining the target size of the compensation element, the elastic deformation of the gland component under the final tightening state due to the tightening torque is also introduced as a correction factor to compensate and correct the difference between the first gap value and the target gap value.

[0066] In practice, the elastic deformation of the gland component under the tightened state is first obtained through mechanical calculation or finite element analysis based on the material, geometry and tightening torque of the fastening bolts. Then, the elastic deformation is superimposed on the target size of the compensation element.

[0067] For example, if the gland component will undergo 0.02 mm of elastic compression deformation when it is tightened, the thickness of the compensating element should be increased by 0.02 mm based on the difference to compensate for the effect of this elastic deformation on the final gap.

[0068] As another preferred embodiment of step S5, when determining the target size of the compensation element, the actual total axial displacement of the pressure cap component during the period from the start of movement to reaching the fitting reference in step S2 is also obtained, and the actual total axial displacement is compared with the theoretical total axial displacement. Based on the comparison result, the displacement deviation compensation amount is generated. The difference between the first gap value and the target gap value is used as the thickness of the base gasket, and then the displacement deviation compensation amount is superimposed to obtain the target size of the compensation element.

[0069] In practice, the theoretical total axial displacement can be calculated based on the theoretical design dimensions of parts such as the design depth of the bearing mounting hole in the support component, the design width of the bearing outer ring, and the design height of the stop of the gland component. The actual total axial displacement is the actual displacement value recorded by the force-displacement monitoring system during the movement from the gland component to the contact reference in step S2.

[0070] The deviation between the actual total axial displacement and the theoretical total axial displacement reflects the cumulative deviation of the actual dimensions of each component of the gearbox relative to the design dimensions. Adding this deviation as a compensation to the shim thickness is equivalent to using the measured individual dimensional deviations to individually correct the shim thickness, ensuring that the clearance adjustment of each gearbox precisely matches its own actual dimensional state.

[0071] After determining the target gap value in step S4 and before determining the size of the compensation element in step S5, an out-of-tolerance warning step can also be set.

[0072] In practice, the first gap value obtained in step S3 is compared with the target gap value determined in step S4.

[0073] If the first gap value is greater than or equal to the target gap value, it means that the difference between the two can be filled by selecting a compensation element of appropriate thickness, and the adjustment process can continue normally. If the first gap value is less than the target gap value, it means that even without any compensation element, i.e., the thickness of the compensation element is zero, the gap between the gland component and the support component is already less than the target gap value. If assembly is forced at this time, the gland component will over-tighten the bearing, causing the bearing to overheat or even burn out during operation.

[0074] If the initial clearance value is less than the target clearance value, it usually indicates that the currently assembled parts have dimensional deviations. For example, the bearing mounting holes of the support component may be machined too shallow, the outer ring width of the bearing may be too large, or the stop height of the gland component may be too small. In this case, it should be determined that the currently assembled parts have dimensional deviations, an alarm signal should be issued, the current adjustment process should be terminated, and the operator should be notified to re-inspect or replace the relevant parts.

[0075] The following describes the actual assembly process of the gearbox clearance adjustment technology of the present invention, using two specific embodiments and a comparative example, and compares the assembly effects of the traditional process with those of the present process. All embodiments in this case are for the same model of engineering drilling rig travel gearbox, the assembly object is the same model of tapered roller bearing, the design target clearance is 0.25mm, and the gearbox's rated transmission torque is 2200 Nm. The helix angle of the helical gear is 18°.

[0076] Note: Examples 1 and 2 are preferred extensions of the process of the present invention with different processes; the comparative example is the industry's traditional gasket trial fitting process.

[0077] Example 1 Using the basic process and tightening torque elastic deformation correction of this invention, the simulated preload function is not enabled.

[0078] S1: Cold press the tapered roller bearing into the bearing mounting position of the support component without placing a compensation shim, and lightly pre-tighten the cover component to the support component with bolts to form an initial clearance.

[0079] S2: The servo tightening system applies an increasing axial preload to the gland bolts and collects the preload-axial displacement curve at a sampling frequency of 1000Hz. It identifies the inflection point of the curve slope change and extrapolates the theoretical contact point by fitting the data of the two segments before and after contact. Tightening stops after the contact reference is reached. The servo brake is activated to maintain pressure and lock the axial position of the gland to prevent springback.

[0080] S3: Use a depth micrometer to measure the gap at four evenly distributed points around the end face of the gland flange, and take the arithmetic mean to obtain the first gap value G1=0.41mm.

[0081] S4: Input the helical gear helix angle and rated torque to the assembly control system; the system mechanical model calculates the bearing axial force component and the end face displacement corresponding to the bearing axial stiffness, superimposes lubrication film compensation and thermal expansion compensation, and outputs the target clearance G. t =0.25mm.

[0082] S5: Base gasket thickness: H0 = G1 - G t =0.16mm; Based on the material of the gland component and the bolt tightening torque, the elastic compression deformation of the gland is calculated to be ΔH=0.02mm; Target thickness of the compensation element: H = H0 + ΔH = 0.16 + 0.02 = 0.18 mm; A 0.18mm thick steel adjusting shim was selected as the compensation element and placed on the mating surface between the gland and the support component. The gland bolts were tightened to the specified torque, and the assembly was completed. After assembly, the actual measured axial working clearance of the bearing was 0.247mm.

[0083] Example 2 The complete process of this invention includes functions for simulating axial preload and compensating for displacement deviation ΔL.

[0084] S1: The bearing is cold-pressed and assembled, and the gland is lightly pre-tightened without a gasket to form an initial gap.

[0085] S2: Servo tightening force-displacement curve is collected and fitted to obtain the theoretical fitting reference point; the mechanical wedge locking mechanism holds the pressure and locks the position of the pressure cap, recording the actual total displacement L of the pressure cap during this process. 实 =1.22mm; The theoretical axial displacement L is obtained from the calculation of the part's theoretical dimensions. 理=1.20mm, displacement deviation compensation ΔL=L 实 -L 理 =0.02mm.

[0086] S3: The average of multiple measurements yields a first gap G1 = 0.40 mm under the fit reference.

[0087] Simulated preload step: Apply a simulated axial preload equivalent to the rated working condition along the bearing axis using the tooling, measure the clearance again, and update the first clearance G'1=0.39mm.

[0088] S4: The assembly control system inputs the transmission component's screw parameters and rated torque, and automatically calculates and outputs the target clearance G. t =0.25mm.

[0089] S5: Base gasket thickness H'0 = G'1 - G t =0.14mm; superimposed displacement deviation compensation ΔL=0.02mm, and then superimposed elastic deformation of the gland fastening ΔH=0.02mm; Target thickness of compensation element: H'=H'0+ΔL+ΔH=0.14+0.02+0.02=0.18mm; Select a 0.18mm adjusting shim, place it on the mating surface, and tighten the bolts according to the process torque. After assembly, the actual measured axial working clearance of the bearing is 0.252mm.

[0090] Comparative Example Using existing industry experience—repeated trial fitting of shims—we assembled the same model of drilling rig travel gearbox, using parts from the same batch.

[0091] 1) Based on the theoretical dimensions in the drawings, the operator initially selected a shim thickness of 0.20mm; 2) Install the gasket and tighten the cover bolts; manually check the axial movement of the bearing, and the actual clearance is found to be 0.33mm, which is too large; 3) Remove the pressure cap, replace the 0.28mm thicker gasket, and reassemble and tighten; re-measure the gap to 0.17mm, which is too small and close to over-tightening; 4) Disassemble again, replace the 0.24mm gasket, re-measure the gap after reassembly. The gap is 0.22mm, which meets the allowable range. Assembly is complete.

[0092] This component underwent three disassembly and reassembly trials, with the final measured working clearance being 0.22mm. For batch testing and comparison of multiple samples, ten gearboxes from the same batch were selected and assembled using the processes of Example 1, Example 2, and the traditional process. The assembly and debugging time per unit, actual axial clearance after assembly, temperature rise test (bearing outer ring temperature rise during 2 hours of continuous operation under rated conditions), and abnormal noise failure rate were statistically analyzed. The comparative data are shown in the table below: The comparison results in the table above show that: 1. Compared with the traditional process of repeated trial fitting, the present invention's Embodiments 1 and 2 do not require multiple disassembly and assembly of the test gaskets, thus greatly shortening the assembly time; 2. In Examples 1 and 2, the bearing clearances after assembly are concentrated around the design target clearance of 0.25mm, with very small dispersion and high product assembly consistency; in contrast, the clearances of the traditional process in the comparison example fluctuate greatly, and the clearances of some samples are too small or too large. 3. Under rated operating conditions, the gearbox bearings assembled using this process have lower temperature rise and no assembly noise defects; the traditional process resulted in 2 units of defective parts with abnormal noise, corresponding to clearances deviating from the design range.

[0093] Compared to Example 1, Example 2 adds simulated preload and displacement deviation compensation steps, further narrowing the gap dispersion and reducing the bearing operating temperature rise, but slightly increasing the assembly time. It is suitable for mass production scenarios of heavy-duty gearboxes with higher reliability requirements. Example 1 has relatively simple steps, balancing assembly efficiency and gap accuracy, and is suitable for mass assembly under normal working conditions.

[0094] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A gearbox clearance adjustment process, characterized in that, Includes the following steps: S1: Install the bearing in the bearing mounting position of the support member, and install the cover member on the support member on the axial side corresponding to the bearing, so that an initial gap is formed between the cover member and the support member; S2: Drive the gland member to move axially toward the bearing until the inner end face of the gland member and the corresponding end face of the bearing reach the contact reference; S3: Obtain the first gap value between the gland member and the support member under the fitting reference; S4: Determine the target clearance value that needs to be maintained between the gland member and the bearing based on the axial load experienced by the bearing in the working state; S5: Determine the target size of the compensation element based on the difference between the first gap value and the target gap value, and select the compensation element of the corresponding size to be placed between the cover member and the support member, so as to maintain the target gap between the inner end face of the cover member and the corresponding end face of the bearing in the final tightened state.

2. The gearbox clearance adjustment process as described in claim 1, characterized in that, In step S2, the specific method for driving the pressure cap component to move to the fitting reference is as follows: An increasing axial preload is applied to the gland component by a tightening device, and the relationship curve between the preload and the axial displacement of the gland component is collected in real time. When the relationship curve shows a sudden inflection point in the slope that indicates physical contact between the inner end face of the gland component and the corresponding end face of the bearing, it is determined that the fitting reference has been reached and the drive is stopped.

3. The gearbox clearance adjustment process as described in claim 2, characterized in that, In step S2, when identifying the inflection point of the slope change, the linear segment force-displacement data before contact and the nonlinear segment force-displacement data after contact are fitted and extrapolated respectively. The intersection of the two fitted curves is determined as the theoretical fitting point, and the theoretical fitting point is used as the fitting reference.

4. The gearbox clearance adjustment process as described in claim 1, characterized in that, Between step S2 and step S3, the following is also included: The pressure-holding device maintains the current axial position of the gland member to prevent axial rebound of the gland member before measurement, and then performs the gap measurement operation in step S3.

5. The gearbox clearance adjustment process as described in claim 1, characterized in that, Between step S3 and step S4, the following is also included: A preload simulating the axial load under the working state is applied to the bearing along the bearing axis, and the gap value between the cover member and the support member is remeasured under the preload state. The remeasured gap value is used as the updated first gap value to participate in the calculation of subsequent steps S4 and S5.

6. The gearbox clearance adjustment process as described in claim 1, characterized in that, In step S4, determining the target clearance value based on the axial load experienced by the bearing during operation includes: Obtain the helical parameters and transmitted torque of the rotary transmission component inside the gearbox, and calculate the axial component force acting on the bearing; By combining the axial stiffness characteristics of the bearing, the displacement of the corresponding end face of the bearing under the action of the axial component force is obtained. The target gap value is obtained by superimposing the preset lubrication and thermal expansion compensation amounts.

7. The gearbox clearance adjustment process as described in claim 6, characterized in that, In step S4, the calculation of the target gap value is automatically completed by the mechanical model built into the assembly control system. After the operator inputs the helical parameters and torque parameters of the rotary transmission component, the system automatically outputs the target gap value and generates the size command of the compensation element.

8. The gearbox clearance adjustment process as described in claim 1, characterized in that, In step S5, when determining the target size of the compensation element, the elastic deformation of the gland member under the final tightening state due to the tightening torque is also introduced as a correction factor to compensate and correct the difference between the first gap value and the target gap value.

9. The gearbox clearance adjustment process as described in claim 1, characterized in that, In step S5, when determining the target size of the compensation element, the total actual axial displacement L of the pressure cap member during the period from the start of movement to reaching the fitting reference is obtained in step S2. 实 And the actual total axial displacement L 实 Compared with the theoretical total axial displacement L 理 The comparison is performed, and the displacement deviation compensation amount ΔL is generated based on the comparison results. The difference between the first gap value and the target gap value is used as the base shim thickness, and then the displacement deviation compensation amount ΔL is added to obtain the target size of the compensation element.

10. A gearbox, characterized in that, It is assembled using the gearbox clearance adjustment process described in any one of claims 1-9.

Images