A pump shaft connection structure, a hydraulic pump, and engineering machinery

Abstract

This utility model discloses a pump shaft connection structure, a hydraulic pump, and engineering machinery, belonging to the technical field of engineering machinery. It includes a pump shaft, a pump shaft flange, bolts, a first gasket, and a second gasket. This utility model installs two gaskets on the bolts connecting the pump shaft and the pump shaft flange. The first gasket is configured as a fixing gasket, and the second gasket as an isolation gasket. The second gasket creates an axial gap between the first gasket and the pump shaft flange, reducing the contact area and frequency between the first gasket and the pump shaft flange during operation. This reduces the transmission of circumferential micro-movements of the pump shaft flange to the first gasket, ensuring that the first gasket essentially does not generate circumferential friction on the bolts that could cause loosening. This ensures a stable connection between the pump shaft flange and the pump shaft, reducing the probability of the pump shaft flange impacting the pump shaft step due to bolt loosening, and effectively protecting the pump shaft.

Description

Technical Field

[0001] This utility model belongs to the field of engineering machinery technology, and relates to hydraulic pumps used in engineering machinery. Specifically, it relates to a connection structure for a pump shaft. Background Technology

[0002] Hydraulic pumps are used as the core power conversion component in many current engineering vehicles (such as excavators, loaders, road rollers, cranes and transporters) and agricultural machinery (such as drilling equipment and shovels). They convert the mechanical energy of the engine into hydraulic energy, drive the hydraulic system in the engineering machinery, and then control the actuator to complete the corresponding actions.

[0003] When connecting a hydraulic pump to an engine, a flange is typically used to rigidly connect the pump shaft to the engine's output shaft. The connection between the flange and the pump shaft uses bolts and gaskets. Because a gap inevitably exists between the flange and the pump shaft, when the engine's output shaft drives the pump shaft to rotate, a slight circumferential movement occurs between the flange and the pump shaft. This movement is transmitted to the gasket, generating circumferential friction between the gasket and the bolts. Over time, this can cause the bolts to loosen. Once the bolts are loose, vibrations generated by the engine during operation are transmitted to the flange, causing it to vibrate. This vibration impacts the stepped surface of the pump shaft, resulting in tooth marks on the stepped surface. Even with an oil seal installed, oil leakage will still occur.

[0004] The information disclosed in this background section is only intended to enhance the understanding of the background technology of this application, and therefore may include prior art that is not known to those skilled in the art. Summary of the Invention

[0005] This utility model addresses at least one of the aforementioned technical problems in the background art by proposing a pump shaft connection structure. By reducing the contact area and frequency between the bolt gasket and the flange, the possibility of bolt loosening is reduced, thereby protecting the pump shaft from impact damage.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: In one aspect, this utility model proposes a pump shaft connection structure, comprising: The pump shaft has a threaded hole at its end; A pump shaft flange having a bottom surface, a seat surface, a mating end face, and a through hole for the pump shaft to pass through, the through hole penetrating the bottom surface and the seat surface, the end of the pump shaft being flush with the seat surface of the pump shaft flange; A bolt, comprising a head and a threaded rod, wherein a first washer and a second washer are mounted on the threaded rod, is used to fasten the pump shaft flange to the pump shaft by threading the threaded rod into the threaded hole; wherein, The first gasket is located between the head of the bolt and the seat surface of the pump shaft flange. The inner diameter of the first gasket is adapted to the diameter of the bolt, and the outer diameter of the first gasket is larger than the diameter of the through hole of the pump shaft flange. The second gasket is located between the first gasket and the end of the pump shaft. The inner diameter of the second gasket is larger than the diameter of the screw and does not contact the screw. The outer diameter of the second gasket is smaller than the diameter of the pump shaft. The second gasket forms an axial gap between the first gasket and the seat surface of the pump shaft flange.

[0007] In some embodiments of this application, in order to facilitate the docking of the pump shaft flange and the engine shaft flange, a flange can be arranged around the outer periphery of the seat surface of the pump shaft flange, and the top surface of the flange forms a docking end face for docking with the engine shaft flange; the outer diameter of the first gasket is configured to be smaller than the inner diameter of the flange, and the first gasket is not in contact with the flange, so as to prevent the circumferential micro-movement of the pump shaft flange from being transmitted to the first gasket, thereby causing the bolts to loosen.

[0008] In some embodiments of this application, the thickness of the second gasket can be configured to be between 5mm and 10mm, that is, a gap of 5mm to 10mm is formed between the first gasket and the seat surface of the pump shaft flange. This ensures that the pump shaft flange and the pump shaft can be securely connected by bolts, and also leaves a suitable gap between the first gasket and the seat surface of the flange to minimize the contact area and contact frequency between the first gasket and the pump shaft flange during operation, thereby blocking the transmission of the circumferential micro-movement of the pump shaft flange to the first gasket and achieving the purpose of preventing bolt loosening.

[0009] In some embodiments of this application, a stepped surface is formed on the pump shaft, and an axial gap is formed between the bottom surface of the pump shaft flange and the stepped surface. In order to prevent the pump shaft flange from hitting the stepped surface of the pump shaft, this application provides a shock-absorbing mechanism in the gap to protect the pump shaft and prevent the pump shaft flange from forming tooth marks on the stepped surface of the pump shaft, which could lead to oil leakage.

[0010] In some embodiments of this application, the shock absorption mechanism may be a rubber pad fitted onto the pump shaft and disposed between the bottom surface of the pump shaft flange and the stepped surface to avoid impact.

[0011] In some embodiments of this application, the damping mechanism may also be formed by adhering rubber to the bottom surface of the pump shaft flange through a vulcanization process and filling the entire axial height of the gap.

[0012] In some embodiments of this application, an external spline can be formed on the pump shaft and an internal spline can be formed in the through hole of the pump shaft flange, thereby enabling the transmission assembly between the pump shaft and the pump shaft flange to be achieved by a spline connection.

[0013] In another aspect, this utility model also proposes a hydraulic pump, comprising: The pump shaft has a threaded hole at its end; A pump shaft flange having a bottom surface, a seat surface, a mating end face, and a through hole for the pump shaft to pass through, the through hole penetrating the bottom surface and the seat surface, the end of the pump shaft being flush with the seat surface of the pump shaft flange; A bolt, comprising a head and a threaded rod, wherein a first washer and a second washer are mounted on the threaded rod, is used to fasten the pump shaft flange to the pump shaft by threading the threaded rod into the threaded hole; wherein, The first gasket is located between the head of the bolt and the seat surface of the pump shaft flange. The inner diameter of the first gasket is adapted to the diameter of the bolt, and the outer diameter of the first gasket is larger than the diameter of the through hole of the pump shaft flange. The second gasket is located between the first gasket and the end of the pump shaft. The inner diameter of the second gasket is larger than the diameter of the screw and does not contact the screw. The outer diameter of the second gasket is smaller than the diameter of the pump shaft. The second gasket forms an axial gap between the first gasket and the seat surface of the pump shaft flange.

[0014] In some embodiments of this application, the hydraulic pump includes a housing with an end face and a shaft hole on the end face; the pump shaft includes a shaft head and a shaft body, the shaft body is located in the housing, the shaft head extends out of the housing through the shaft hole, a threaded hole is formed at the end of the shaft head, and the shaft head is fitted into the through hole of the pump shaft flange; an external spline and a stepped surface are formed on the shaft head, the external spline is located in the through hole of the pump shaft flange for connection with the pump shaft flange spline; the stepped surface is exposed outside the through hole and adjacent to the bottom surface of the pump shaft flange, the stepped surface is higher than or flush with the end face of the housing, and a shock-absorbing mechanism is added to prevent the pump shaft flange from hitting the stepped surface, forming tooth marks on the stepped surface of the pump shaft, causing oil leakage.

[0015] In another aspect, this utility model also proposes an engineering machine, including an engine and a hydraulic pump, wherein the engine has an output shaft on which an engine shaft flange is mounted; the hydraulic pump includes: The pump shaft has a threaded hole at its end; A pump shaft flange has a bottom surface, a seat surface, a mating end face, and a through hole through which the pump shaft passes. The through hole passes through the bottom surface and the seat surface. The end of the pump shaft is flush with the seat surface of the pump shaft flange. The mating end face is connected to the engine shaft flange. The rotation of the engine output shaft drives the pump shaft of the hydraulic pump to rotate. A bolt, comprising a head and a threaded rod, wherein a first washer and a second washer are mounted on the threaded rod, is used to fasten the pump shaft flange to the pump shaft by threading the threaded rod into the threaded hole; wherein, The first gasket is located between the head of the bolt and the seat surface of the pump shaft flange. The inner diameter of the first gasket is adapted to the diameter of the bolt, and the outer diameter of the first gasket is larger than the diameter of the through hole of the pump shaft flange. The second gasket is located between the first gasket and the end of the pump shaft. The inner diameter of the second gasket is larger than the diameter of the screw and does not contact the screw. The outer diameter of the second gasket is smaller than the diameter of the pump shaft. The second gasket forms an axial gap between the first gasket and the seat surface of the pump shaft flange.

[0016] Compared with the prior art, the advantages and positive effects of this utility model are mainly reflected in: 1. This utility model installs two gaskets on the bolts connecting the pump shaft and the pump shaft flange. The first gasket is used for fixing, and the second gasket is used for isolation. The second gasket forms an axial gap between the first gasket and the pump shaft flange, reducing the contact area and frequency between the first gasket and the pump shaft flange during operation. This reduces the transmission of circumferential micro-movements of the pump shaft flange to the first gasket, ensuring that the first gasket does not generate circumferential friction on the bolt that could cause it to loosen. This ensures a stable connection between the pump shaft flange and the pump shaft, reduces the probability of the pump shaft flange hitting the pump shaft step due to bolt loosening, and effectively protects the pump shaft.

[0017] 2. This utility model, by configuring the outer diameter of the second gasket to be smaller than the diameter of the pump shaft, ensures that the second gasket has no contact with the pump shaft flange. This prevents the circumferential micro-movements of the pump shaft flange from being transmitted to the second gasket, and then through the second gasket to the first gasket, causing the bolts to loosen. By configuring the inner diameter of the second gasket to be larger than the diameter of the bolt, this also ensures that the second gasket has no contact with the bolt, thereby preventing the second gasket from generating friction on the bolt and eliminating any potential influence of the second gasket on the bolt.

[0018] 3. Applying the pump shaft connection structure of this utility model to a hydraulic pump can keep the total shaft length of the engine output shaft and the hydraulic pump shaft unchanged, thus eliminating the need to adjust the existing installation positions of the engine and hydraulic pump in the construction machinery, facilitating the upgrading and modification of existing construction machinery. At the same time, it avoids the problem of decreased torsional resistance due to increased total shaft length.

[0019] 4. This utility model adds a shock-absorbing mechanism between the pump shaft flange and the stepped surface of the pump shaft. On the one hand, it can reduce the vibration of the pump shaft flange, and on the other hand, it can reduce the impact of the pump shaft flange on the stepped surface of the pump shaft, thus avoiding tooth marks on the stepped surface of the pump shaft and causing oil leakage of the hydraulic pump.

[0020] Other features and advantages of this utility model will become clearer after reading the detailed embodiments of this utility model in conjunction with the accompanying drawings. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without any creative effort.

[0022] Figure 1 This is a schematic diagram of the overall structure of one embodiment of the hydraulic pump proposed in this utility model; Figure 2 yes Figure 1 An exploded structural diagram of one embodiment of the hydraulic pump shown; Figure 3 yes Figure 1 A partial sectional perspective view of one embodiment of the hydraulic pump shown; Figure 4 yes Figure 1 A partial cross-sectional isometric view of one embodiment of the hydraulic pump shown.

[0023] In the figure, 100 is the housing; 110 is the end face; 120 is the shaft hole; 200 is the pump shaft; 210 is the end; 211 is the threaded hole; 220 is the external spline; 230 is the stepped surface; 300 is the pump shaft flange; 310 is the lower part; 311 is the bottom surface; 312 is the seat surface; 313 is the through hole; 314 is the internal spline; 320 is the upper part; 321 is the flange; 322 is the mating end face; 323 is the mounting hole; 400 is the bolt; 410 is the head; 420 is the screw; 500 is the first gasket; 600 is the second gasket; 700 is the clearance; and 800 is the shock absorption mechanism. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present utility model, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the protection scope of the present utility model.

[0025] In the description of this utility model, it should be understood that the terms "upper", "lower", "inner", "outer", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed or operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0026] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, an integral molding, or an internal connection of components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances. In the description of the embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0027] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0028] In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0029] This embodiment takes a hydraulic pump as an example and designs the connection structure between the pump shaft and the pump shaft flange.

[0030] At present, many construction machinery still use hydraulic systems as the core of power transmission and precise control. The hydraulic system converts the mechanical energy of the engine or electric motor into high-pressure oil through a hydraulic pump, which drives hydraulic cylinders, motors and other actuators to complete linear motion, rotation or swinging actions, so as to realize the various functions of construction machinery.

[0031] Let's take a hydraulic pump and engine as an example. To enable the engine to drive the hydraulic pump, a flange is usually installed on both the engine's output shaft and the hydraulic pump's pump shaft. The flange installed on the engine's output shaft can be called the engine shaft flange, and the flange installed on the hydraulic pump shaft can be called the pump shaft flange. By connecting the engine shaft flange and the pump shaft flange, the rotation of the engine's output shaft drives the hydraulic pump's pump shaft to rotate, which in turn drives the pistons or gears inside the pump body to move, thereby increasing the hydraulic oil pressure. The high-pressure hydraulic oil then drives the hydraulic cylinders, motors, and other actuators to move.

[0032] In order to achieve a stable connection between the hydraulic pump shaft and the pump shaft flange, this embodiment incorporates an anti-loosening design for the bolts connecting the pump shaft and the pump shaft flange to prevent damage to the pump shaft caused by loosening of the pump shaft flange.

[0033] Combination Figure 1 , Figure 2 As shown, the hydraulic pump in this embodiment mainly includes key components such as a housing 100, a pump shaft 200, and a pump shaft flange 300. A shaft hole 120 is provided on the end face 110 of the housing 100 facing the engine, through which the pump shaft 200 passes. For clarity, this embodiment divides the pump shaft 200 into two parts: a shaft head and a shaft body. The shaft body is installed in the housing 100, and the shaft head protrudes from the housing 100 through the shaft hole 120 for assembling the pump shaft flange 300.

[0034] The pump shaft flange 300 in this embodiment has a T-shaped cross-sectional shape, such as... Figure 3 As shown, it includes a cylindrical lower part 310 and an annular upper part 320. The cylindrical lower part 310 has a bottom surface 311 and a seat surface 312 positioned opposite each other, with a through hole 313 formed between the bottom surface 311 and the seat surface 312 for the shaft head of the pump shaft 200 to pass through. A flange 321 is formed around the outer periphery of the seat surface 312, and the top surface of the flange 321 forms the annular upper part 320. Multiple mounting holes 323 are provided in the annular upper part 320 for connection and assembly with the engine shaft flange. The annular top surface of the upper part 320 is designed as a smooth plane, forming the mating end face 322 of the flange to ensure a tight fit between the pump shaft flange 300 and the engine shaft flange.

[0035] To achieve effective transmission, an external spline 220 is formed on the head of the pump shaft 200, and an internal spline 314 is formed in the through hole 313 of the pump shaft flange 300. The external spline 220 of the pump shaft 200 is inserted into the through hole 313 of the pump shaft flange 300 and assembled with the internal spline 314. The spline connection method effectively transmits the rotation of the pump shaft flange 300 to the pump shaft 200, so as to drive the pump shaft 200 to rotate synchronously.

[0036] To improve the stability of the pump shaft flange 300 mounted on the pump shaft 200, this embodiment uses a threaded connection to fix the pump shaft flange 300 to the pump shaft 200. Specifically, a threaded hole 211 can be formed at the end 210 of the pump shaft 200, that is, the end of the shaft head, along the axial direction of the pump shaft 200, for connection. Figure 2 , Figure 3 As shown, the end 210 of the shaft head is flush with the seat surface 312 of the pump shaft flange 300. A gasket 500 and a bolt 400 are installed on the seat surface 312. The bolt 400 is threaded into the threaded hole 211 to achieve the fixed assembly of the pump shaft flange 300 on the pump shaft 200.

[0037] Because there will inevitably be a gap between the pump shaft flange 300 and the pump shaft 200, the pump shaft flange 300 will have a slight circumferential movement relative to the pump shaft 200. This slight circumferential movement is transmitted to the gasket 500, which will cause the gasket 500 to form a circumferential friction force on the bolt 400. Over time, this will cause the bolt 400 to loosen.

[0038] To address the issue of bolt 400 unexpectedly loosening, this embodiment includes two annular washers for bolt 400, referred to as the first washer 500 and the second washer 600, respectively. Figures 2 to 4 As shown.

[0039] Bolt 400 includes a head 410 and a threaded rod 420. The inner diameter of the first washer 500 is matched to the diameter of the threaded rod 420; that is, the inner diameter of the first washer 500 is slightly larger than the diameter of the threaded rod 420 and significantly smaller than the diameter of the bolt head 410. The outer diameter of the first washer 500 is larger than the diameter of the through hole 313 on the pump shaft flange 300 and smaller than the inner diameter of the flange 321 on the pump shaft flange 300. The inner diameter of the second washer 600 is larger than the diameter of the threaded rod 420, and the outer diameter of the second washer 600 is smaller than the diameter of the pump shaft 200.

[0040] The second gasket 600 is placed on the end 210 of the pump shaft 200, and the inner ring of the second gasket 600 is adjusted to be completely located on the outer periphery of the threaded hole 211 on the pump shaft 200, and the outer ring of the second gasket 600 is completely located within the outer periphery of the end 210 of the pump shaft. Since the end 210 of the pump shaft 200 is flush with the seat surface 312 of the pump shaft flange 300, the top surface of the second gasket 600 is higher than the seat surface 312 of the pump shaft flange 300.

[0041] Place the first gasket 500 on the top surface of the second gasket 600, and adjust the center of the first gasket 500 to be basically located on the axis of the threaded hole 211 on the pump shaft 200.

[0042] The bolt 400's threaded portion 420 is inserted into the inner rings of the first washer 500 and the second washer 600, and then into the threaded hole 211 on the pump shaft 200, where it is threaded until tightened. At this point, the first washer 500 is located between the head 410 of the bolt 400 and the second washer 600, and the second washer 600 is located between the first washer 500 and the end 210 of the pump shaft 200. Furthermore, the inner ring of the second washer 600 is not in contact with the threaded portion 420 of the bolt 400, and the outer ring of the second washer 600 is not in contact with the pump shaft flange 300. The inner ring of the first washer 500 is either not in contact with or partially in contact with the threaded portion 420, and the outer ring of the first washer 500 is not in contact with the flange 321 of the pump shaft flange 300.

[0043] Due to the presence of the second gasket 600, the first gasket 500 is raised, forming an axial gap 700 between the first gasket 500 and the seat surface 312 of the pump shaft flange 300. At this time, there is no contact between the first gasket 500 and the pump shaft flange 300, and the circumferential micro-movement generated by the pump shaft flange 300 will not be transmitted to the first gasket 500, causing the bolt 400 to loosen.

[0044] However, considering that during operation, the vibration generated by the engine will be transmitted to the pump shaft flange 300 through its output shaft and engine shaft flange, causing the pump shaft flange 300 to vibrate, which in turn causes the seat surface 312 of the pump shaft flange 300 to contact the first gasket 500, thereby transmitting the circumferential micro-motion generated by the pump shaft flange 300 to the first gasket 500. To prevent the seat surface 312 of the pump shaft flange 300 from contacting the first gasket 500 when it vibrates, the thickness of the second gasket 600 needs to be increased, thereby increasing the axial clearance 700 formed between the first gasket 500 and the seat surface 312 of the pump shaft flange 300. However, increasing the gap 700 will reduce the stability of the connection between the pump shaft flange 300 and the pump shaft 200 via bolts 400. Therefore, the width of the gap 700 needs to be reasonably configured. While ensuring a stable connection, the contact area and frequency of the first gasket 500 and the seat surface 312 of the pump shaft flange 300 should be minimized as much as possible. This will reduce the possibility of the pump shaft flange 300 transmitting circumferential micro-movements to the first gasket 500, thereby preventing the bolts 400 from loosening.

[0045] In this embodiment, the thickness of the second gasket 600 is configured to be between 5mm and 10mm, so as to form a suitable axial clearance 700 between the first gasket 500 and the seat surface 312 of the pump shaft flange 300.

[0046] In some embodiments, the second gasket 600 may be made by stacking multiple conventional gaskets to achieve the required thickness, thereby simplifying the process and reducing costs.

[0047] Because a step is formed on the pump shaft 200 of the hydraulic pump, for example, a stepped surface 230 is formed at the position of the shaft head near the end face 110 of the housing, such as... Figure 3 As shown. When bolt 400 loosens, the vibration of pump shaft flange 300 will impact the stepped surface 230, causing tooth marks to form on the stepped surface 230. Even if an oil seal is installed, oil leakage will still occur.

[0048] In order to protect the pump shaft 200 and prevent its stepped surface 230 from being damaged by impact, this embodiment provides a shock-absorbing mechanism 800 in the axial gap formed between the bottom surface 311 of the pump shaft flange 300 and the stepped surface 230 of the shaft head to reduce axial impact.

[0049] In some embodiments, the shock absorption mechanism 800 may be a rubber pad fitted around the outer periphery of the pump shaft 200 and positioned in the axial gap formed between the bottom surface 311 of the pump shaft flange 300 and the shaft head step surface 230, so as to buffer the axial impact of the pump shaft flange 300.

[0050] In other embodiments, the damping mechanism 800 can be made of rubber that is adhered to the bottom surface 311 of the pump shaft flange 300 by a vulcanization process, and fills the entire axial gap formed between the bottom surface 311 of the pump shaft flange 300 and the shaft head step surface 230, thereby playing an axial buffering role.

[0051] Industrial applicability

[0052] The hydraulic pump of this embodiment is applied to engineering machinery with a hydraulic system, and the pump shaft flange 300 of the hydraulic pump is connected to the flange on the output shaft of the engine in the engineering machinery.

[0053] When the engine is started, the engine's output shaft rotates, which in turn drives the hydraulic pump's pump shaft 200 to rotate via the engine shaft flange and pump shaft flange 300, thereby outputting high-pressure hydraulic oil to drive the actuators (such as hydraulic cylinders, motors, etc.) in the construction machinery to move linearly, rotate, or oscillate, thus completing the various functions of the construction machinery.

[0054] During the rotation of the pump shaft 200 and pump shaft flange 300 of the hydraulic pump, the pump shaft flange 300 will produce circumferential micro-movement. Since there is an axial clearance 700 between the first gasket 500 and the pump shaft flange 300, this circumferential micro-movement will not be transmitted to the first gasket 500. Consequently, the first gasket 500 will not generate circumferential friction on the bolt 400, so the bolt 400 will not loosen.

[0055] When the engine vibrates, the vibration is transmitted to the pump shaft flange 300 through the engine output shaft and engine shaft flange, causing the pump shaft flange 300 to vibrate axially. The axial vibration of the pump shaft flange 300 will cause its seat surface 312 to occasionally come into contact with the first gasket 500. However, the contact area and the frequency of contact are limited. Therefore, the micro-movements around the pump shaft flange 300 can only be transmitted to the first gasket 500 with a small probability, so the probability of the bolt 400 loosening is extremely small.

[0056] Furthermore, since a damping mechanism 800 is filled between the bottom surface 311 of the pump shaft flange 300 and the stepped surface 230 of the pump shaft 200, the damping mechanism 800 can reduce the axial vibration of the pump shaft flange 300 to further reduce the contact frequency between the pump shaft flange 300 and the first gasket 500; on the other hand, it can reduce the axial impact of the pump shaft flange 300 on the pump shaft stepped surface 230, thereby protecting the pump shaft 200 from impact damage.

[0057] Applying the hydraulic pump of this embodiment to construction machinery will not cause a change in the total shaft length of the engine output shaft and the hydraulic pump shaft. Therefore, the engine and hydraulic pump can be directly installed in their inherent positions in the construction machinery without adjustment, thereby simplifying the difficulty of upgrading and modifying existing construction machinery.

[0058] Of course, the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it; although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions claimed by this utility model.

Claims

1. A pump shaft connection structure, characterized in that, include: The pump shaft has a threaded hole at its end; A pump shaft flange having a bottom surface, a seat surface, a mating end face, and a through hole for the pump shaft to pass through, the through hole penetrating the bottom surface and the seat surface, the end of the pump shaft being flush with the seat surface of the pump shaft flange; A bolt, comprising a head and a threaded rod, wherein a first washer and a second washer are mounted on the threaded rod, is used to fasten the pump shaft flange to the pump shaft by threading the threaded rod into the threaded hole; wherein, The first gasket is located between the head of the bolt and the seat surface of the pump shaft flange. The inner diameter of the first gasket is adapted to the diameter of the bolt, and the outer diameter of the first gasket is larger than the diameter of the through hole of the pump shaft flange. The second gasket is located between the first gasket and the end of the pump shaft. The inner diameter of the second gasket is larger than the diameter of the screw and does not contact the screw. The outer diameter of the second gasket is smaller than the diameter of the pump shaft. The second gasket forms an axial gap between the first gasket and the seat surface of the pump shaft flange.

2. The pump shaft connection structure according to claim 1, characterized in that, A flange is provided around the outer periphery of the seat surface of the pump shaft flange, and the top surface of the flange forms the mating end face for mating with the engine shaft flange. The outer diameter of the first gasket is smaller than the inner diameter of the flange, and the first gasket is not in contact with the flange.

3. The pump shaft connection structure according to claim 1, characterized in that, The thickness of the second gasket is between 5mm and 10mm.

4. The pump shaft connection structure according to any one of claims 1 to 3, characterized in that, A stepped surface is formed on the pump shaft, and an axial gap is formed between the bottom surface of the pump shaft flange and the stepped surface. A shock-absorbing mechanism is provided in the gap.

5. The pump shaft connection structure according to claim 4, characterized in that, The shock absorption mechanism is a rubber pad, which is fitted onto the pump shaft.

6. The pump shaft connection structure according to claim 4, characterized in that, The shock absorption mechanism is formed by adhering rubber to the bottom surface of the pump shaft flange through a vulcanization process and filling the entire axial height of the gap.

7. The pump shaft connection structure according to claim 4, characterized in that, An external spline is formed on the pump shaft, and an internal spline is formed in the through hole of the pump shaft flange. The pump shaft is connected to the pump shaft flange via a spline.

8. A hydraulic pump, characterized in that, It is equipped with a pump shaft connection structure as described in any one of claims 1 to 7.

9. The hydraulic pump according to claim 8, characterized in that, The hydraulic pump includes a housing, the housing having an end face, and a shaft hole being formed on the end face; The pump shaft includes a shaft head and a shaft body. The shaft body is located in the housing. The shaft head extends out of the housing through the shaft hole. The threaded hole is opened at the end of the shaft head. The shaft head is assembled in the through hole of the pump shaft flange. An external spline and a stepped surface are formed on the shaft head. The external spline is located in the through hole of the pump shaft flange. The stepped surface is exposed outside the through hole and adjacent to the bottom surface of the pump shaft flange. The stepped surface is higher than or flush with the end face of the housing.

10. An engineering machinery, characterized in that, The device includes an engine and a hydraulic pump as described in claim 8 or 9, wherein the engine has an output shaft with an engine shaft flange mounted on the output shaft, the engine shaft flange being connected to the mating end face of the pump shaft flange of the hydraulic pump, and the rotation of the engine output shaft drives the pump shaft of the hydraulic pump to rotate.

Images