Hydrostatic pressure spindle mechanism and machine tool

Abstract

The utility model discloses a hydrostatic pressure spindle mechanism and a machine tool. The hydrostatic pressure spindle mechanism comprises a shell, a spindle, a driving assembly, a brake assembly and a control assembly. The shell is provided with an accommodating cavity and a mounting bracket; the main shaft is rotatably arranged in the accommodating cavity, and the main shaft is provided with an external section; the driving assembly is in driving connection with the external section; the brake assembly is arranged at the end, away from the containing cavity, of the external section in a sleeving mode and comprises a first friction part and a second friction part, the first friction part is provided with an elastic piece, and the elastic piece is provided with a first position making contact with the second friction part so as to lock the main shaft and a second position separated from the second friction part so as to enable the main shaft to rotate. The control assembly is electrically connected with the driving assembly and the brake assembly and controls the elastic piece to be switched between the first position and the second position according to electric signals transmitted by the driving assembly. The problem that in the prior art, a hydrostatic pressure main shaft is difficult to stop rotating in time when encountering sudden power failure can be solved.

Description

Technical Field

[0001] This application relates to the field of machine tool technology, and more specifically, to a hydrostatic spindle mechanism and machine tool. Background Technology

[0002] As a core component of ultra-precision machine tools, the precision and rigidity of hydrostatic spindles significantly influence the machining accuracy of parts. Hydrostatic spindles utilize hydrostatic bearings as support components. These bearings rely on an external hydraulic oil supply system to forcibly inject lubricating oil, generating a pressure oil film. This pressure oil film separates the relatively moving parts from the support components, achieving full hydrostatic friction. Therefore, hydrostatic spindles possess advantages such as low frictional resistance, long service life, wide speed range, good vibration resistance, high spindle rotation accuracy, and good adaptability, making them widely used in the field of ultra-precision machine tool machining.

[0003] Existing technologies using externally mounted hydrostatic spindles have certain problems. While these external motors drive the spindle via a belt, excessive belt tension can cause radial runout, affecting its rotational accuracy. Furthermore, during spindle rotation, a sudden power outage can cause the spindle to continue rotating due to inertia. If this doesn't stop in time, it can easily seize up and become dry, leading to severe damage. Utility Model Content

[0004] The main objective of this application is to provide a hydrostatic spindle mechanism and machine tool to solve the problem that existing hydrostatic spindles are difficult to stop rotating in time when encountering a sudden power outage.

[0005] According to one aspect of this application, a hydrostatic spindle mechanism is provided, comprising:

[0006] A housing having a receiving cavity and a mounting bracket;

[0007] A main shaft, which is rotatably disposed within the receiving cavity, and the main shaft has an external section extending out of the receiving cavity;

[0008] A drive assembly, which is connected to the external segment drive to drive the spindle to rotate about its own axis;

[0009] A brake assembly is sleeved on the end of the outer segment away from the receiving cavity. The brake assembly includes a first friction part and a second friction part. The first friction part is disposed on the mounting bracket, and the second friction part is disposed on the outer segment. The first friction part has an elastic sheet. The elastic sheet has a first position that contacts the second friction part to lock the spindle, and a second position that separates from the second friction part to allow the spindle to rotate.

[0010] A control component is electrically connected to both the drive component and the brake component. The control component controls the elastic plate to switch between the first position and the second position based on the electrical signal transmitted by the drive component.

[0011] Furthermore, the control component includes:

[0012] A control power supply is electrically connected to the brake assembly. The control power supply has an on state that controls the elastic plate to be in the first position and an off state that controls the elastic plate to be in the second position.

[0013] The controller is electrically connected to both the control power supply and the drive component. The controller controls the control power supply to switch between the power-on state and the power-off state according to the electrical signals transmitted by the drive component.

[0014] Furthermore, the first friction part is provided with an annular protrusion, the annular protrusion has a clearance channel for the outer segment to pass through, the annular protrusion and the outer edge of the first friction part are provided with an annular groove, and the annular protrusion is provided with a limiting step, the limiting step is arranged around the circumference of the annular protrusion, and the elastic sheet is disposed in the annular groove and abuts against the limiting step.

[0015] Wherein, when the elastic sheet switches from the second position to the first position, the elastic sheet moves along the main shaft axis from the annular groove toward the second friction part and contacts the second friction part, and the distance D of the elastic sheet moving satisfies the relationship: 0.015mm≤D≤0.025mm;

[0016] When the elastic sheet switches from the first position to the second position, the elastic sheet is located in the annular groove and abuts against the limiting step, and the side of the elastic sheet and the annular protrusion near the second friction part remains flush.

[0017] Furthermore, the hydrostatic spindle mechanism also includes an accumulator, which is connected to the spindle via a connecting pipe to at least provide hydraulic oil to the spindle. The accumulator has a pressure holding time T1, and the elastic plate of the brake assembly has a braking time T2 when it switches from the second position to the first position. T1 and T2 satisfy the relationship: T1 > T2.

[0018] Furthermore, the driving component includes:

[0019] A pulley is rotatably fitted onto the outer surface of the outer section, and a predetermined gap exists between the pulley and the mounting bracket.

[0020] A drive motor is connected to the pulley via a belt to drive the pulley to rotate, thereby rotating the main shaft. The drive motor is also electrically connected to the control component.

[0021] Furthermore, the hydrostatic spindle mechanism also includes a bearing assembly, which is sleeved on the outer surface of the outer section. The bearing assembly includes:

[0022] A bearing retaining sleeve is sleeved on the outer surface of the outer section and disposed on the housing; the mounting bracket is connected to the bearing retaining sleeve.

[0023] A rotating bearing assembly is disposed between the bearing retaining sleeve and the pulley. The rotating bearing assembly includes two bearings spaced apart along the axial direction of the main shaft. The inner rings of the two bearings are disposed on the bearing retaining sleeve, and the outer rings of the two bearings are disposed on the pulley.

[0024] Furthermore, both of the aforementioned bearings include deep groove ball bearings or angular contact ball bearings.

[0025] Furthermore, the hydrostatic spindle mechanism also includes an unloading assembly, which is sleeved on the outer surface of the outer section and located on the side of the pulley away from the housing. The unloading assembly includes:

[0026] The unloading sleeve is rotatably fitted onto the outer surface of the outer section and connected to the outer section. The unloading sleeve is provided with a mounting through hole extending along the axial direction of the main shaft.

[0027] A connector is disposed within the mounting through hole and connected between the unloading sleeve and the pulley;

[0028] An elastic element is sleeved on the plug and located between the plug and the inner wall surface of the mounting through hole;

[0029] When the drive motor drives the pulley to rotate, the pulley synchronously drives the unloading sleeve to rotate, which in turn drives the main shaft to rotate.

[0030] Furthermore, the mounting through holes include a plurality of holes, which are spaced apart circumferentially along the unloading sleeve;

[0031] The connector includes multiple connectors, and each connector is disposed in a corresponding manner within a plurality of mounting through holes;

[0032] The elastic element includes multiple elastic elements, which are correspondingly sleeved on multiple plug-in elements and located between the plug-in elements and the inner wall surface of the mounting through hole.

[0033] On the other hand, this application also provides a machine tool, which includes the above-described hydrostatic spindle mechanism.

[0034] Because the control component in this application is electrically connected to both the drive component and the brake component, and the brake component includes a first friction part and a second friction part, with the first friction part having an elastic plate, when the hydrostatic spindle mechanism encounters a sudden power outage, the drive component stops working. At this time, the control component controls the elastic plate to be in the first position and contact the second friction part according to the stop signal transmitted by the drive component, thereby locking the spindle to prevent it from continuing to rotate. When the power to the hydrostatic spindle mechanism is restored, the drive component starts working again. At this time, the control component controls the elastic plate to be in the second position and separate from the second friction part according to the start signal transmitted by the drive component, thereby allowing the spindle to start rotating. The overall structure is simple; by simply electrically connecting the control component to both the drive component and the brake component, the position of the elastic plate can be switched according to the signal transmitted by the drive component. This allows the brake component to quickly lock or release the spindle, preventing the hydrostatic spindle from failing to stop rotating in time when encountering a sudden power outage and thus avoiding dry burning and seizing, effectively improving the reliability and safety of the hydrostatic spindle. Attached Figure Description

[0035] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0036] Figure 1 This is a partial cross-sectional view of the hydrostatic spindle mechanism disclosed in an embodiment of this application;

[0037] Figure 2 The appendices disclosed in the embodiments of this application Figure 1 Enlarged view of region A in the middle;

[0038] Figure 3 The appendices disclosed in the embodiments of this application Figure 1 Enlarged view of region B in the middle;

[0039] Figure 4 This is a schematic diagram showing the connection relationship between the control component, drive component, and brake component disclosed in the embodiments of this application.

[0040] The above figures include the following reference numerals:

[0041] 10. Housing; 101. Receiving cavity; 102. Predetermined gap; 11. Mounting bracket; 20. Main shaft; 21. External section; 30. Drive assembly; 31. Pulley; 32. Drive motor; 40. Brake assembly; 41. First friction part; 411. Annular protrusion; 412. Clearance channel; 413. Annular groove; 414. Limiting step; 42. Second friction part; 43. Elastic sheet; 50. Control assembly; 51. Control power supply; 52. Controller; 60. Bearing assembly; 61. Bearing retaining sleeve; 62. Rotating bearing assembly; 621. Bearing; 70. Unloading assembly; 71. Unloading sleeve; 711. Mounting through hole; 72. Connector; 73. Elastic element. Detailed Implementation

[0042] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0043] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0044] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0045] As described in the background section, in existing externally motored hydrostatic spindles, the external motor drives the spindle via a belt during operation. However, excessive belt tension can easily cause radial wobbling in the spindle, affecting its rotational accuracy. Furthermore, in the event of a sudden power outage, the spindle may continue to rotate due to inertia. If it fails to stop rotating promptly, it may seize up due to overheating, resulting in severe damage. To address this, the inventors of this application have designed a novel hydrostatic spindle mechanism. This mechanism solves the problem of existing hydrostatic spindles failing to stop rotating promptly in the event of a sudden power outage. The following detailed description of the hydrostatic spindle mechanism, in conjunction with the accompanying drawings, will further illustrate this invention.

[0046] See Figures 1 to 4 As shown, according to an embodiment of this application, a hydrostatic spindle mechanism is provided, which includes a housing 10, a spindle 20, a drive assembly 30, a brake assembly 40, and a control assembly 50.

[0047] The housing 10 has a receiving cavity 101 and a mounting bracket 11. The main shaft 20 is rotatably disposed in the receiving cavity 101 and has an external section 21 extending out of the receiving cavity 101. The drive assembly 30 is drivenly connected to the external section 21 to drive the main shaft 20 to rotate around its own axis. The brake assembly 40 is sleeved on the end of the external section 21 away from the receiving cavity 101. The brake assembly 40 includes a first friction part 41 and a second friction part 42. The first friction part 41 is disposed on the mounting bracket 11, and the second friction part 42 is disposed on the external section 21. The first friction part 41 has an elastic piece 43. The elastic piece 43 has a first position that contacts the second friction part 42 to lock the main shaft 20, and a second position that separates from the second friction part 42 to allow the main shaft 20 to rotate. The control assembly 50 is electrically connected to the drive assembly 30 and the brake assembly 40 respectively. The control assembly 50 controls the elastic piece 43 to switch between the first position and the second position according to the electrical signal transmitted by the drive assembly 30.

[0048] In this embodiment, the housing 10 provides installation and protection space for the spindle 20 and facilitates its installation on the machine tool; the drive assembly 30 provides rotational power to the spindle 20. Since the first friction part 41 is mounted on the mounting bracket 11 and the second friction part 42 is mounted on the outer section 21, when the drive assembly 30 drives the spindle 20 to rotate, the second friction part 42 rotates synchronously with the spindle 20, while the first friction part 41 does not rotate. Meanwhile, since the control component 50 in this embodiment is electrically connected to the drive component 30 and the brake component 40 respectively, and the brake component 40 includes a first friction part 41 and a second friction part 42, and the first friction part 41 has an elastic sheet 43, when the hydrostatic spindle mechanism encounters a sudden power failure, the drive component 30 will stop working. At this time, the control component 50 controls the elastic sheet 43 to be in the first position and contact the second friction part 42 according to the stop signal transmitted by the drive component 30, thereby locking the spindle 20 to prevent the spindle 20 from continuing to rotate; when the power of the hydrostatic spindle mechanism is restored, the drive component 30 will start working again. At this time, the control component 50 controls the elastic sheet 43 to be in the second position and separate from the second friction part 42 according to the start signal transmitted by the drive component 30, thereby causing the spindle 20 to start rotating. The overall structure is simple. The control component 50 is electrically connected to the drive component 30 and the brake component 40 respectively. The position of the elastic plate 43 can be switched according to the signal transmitted by the drive component 30. This allows the brake component 40 to quickly lock or release the spindle 20, avoiding the phenomenon of dry burning and seizing when the hydrostatic spindle mechanism encounters a sudden power failure. This effectively improves the reliability and safety of the hydrostatic spindle mechanism.

[0049] Specifically, in this embodiment, the first friction part 41 and the mounting bracket 11 are fixedly connected by screws or other locking components.

[0050] Further, see Figure 4 As shown, the control component 50 in this embodiment includes a control power supply 51 and a controller 52. The control power supply 51 is electrically connected to the brake assembly 40 and has an energized state (controlling the elastic plate 43 to a first position) and an de-energized state (controlling the elastic plate 43 to a second position). The controller 52 is electrically connected to both the control power supply 51 and the drive assembly 30, and controls the control power supply 51 to switch between the energized and de-energized states based on electrical signals transmitted from the drive assembly 30. For example, the control power supply 51 in this embodiment includes an uninterruptible power supply (UPS).

[0051] Specifically, in this embodiment, the brake assembly 40 is a structure that provides protection for the spindle 20 in the event of a sudden power outage. The controller 52, as the core control unit, accurately controls the state of the control power supply 51 based on the electrical signals transmitted from the drive assembly 30. When the hydrostatic spindle mechanism experiences a sudden power outage, the drive assembly 30 stops working. At this time, the control assembly 50 controls the control power supply 51 to be energized based on the stop signal transmitted from the drive assembly 30, thereby controlling the elastic plate 43 to be in the first position and in contact with the second friction part 42, thus locking the spindle 20 to prevent it from continuing to rotate. When the hydrostatic spindle mechanism regains power, the drive assembly 30 starts working again. At this time, the control assembly 50 controls the control power supply 51 to be de-energized based on the start signal transmitted from the drive assembly 30, thereby controlling the elastic plate 43 to be in the second position and separating from the second friction part 42, thus releasing the spindle 20 to allow it to continue rotating. The entire process ensures that the spindle 20 will not seize up and be damaged.

[0052] In other words, the brake assembly 40 in this embodiment is an electrically powered brake. When the control power supply 51 is energized, the elastic sheet 43 contacts the second friction part 42 to provide braking, thereby stopping the spindle 20 from rotating. When the control power supply 51 is de-energized, the elastic sheet 43 separates from the second friction part 42, causing the second friction part 42 to rotate synchronously with the spindle 20. During this process, since the brake assembly 40 is not energized when the spindle 20 drives the second friction part 42 to rotate, the temperature of the brake assembly 40 will not continue to rise. At this time, the brake assembly 40 will not transfer heat to the spindle 20, thereby preventing thermal deformation of the spindle 20 and effectively improving the accuracy of the spindle 20.

[0053] Further, see Figures 1 to 2 As shown, in this embodiment, the first friction part 41 is provided with an annular protrusion 411, the annular protrusion 411 has a clearance channel 412 for the outer segment 21 to pass through, an annular groove 413 is provided between the annular protrusion 411 and the outer edge of the first friction part 41, and a limiting step 414 is provided on the annular protrusion 411. The limiting step 414 is arranged circumferentially around the annular protrusion 411, and the elastic piece 43 is disposed in the annular groove 413 and abuts against the limiting step 414; wherein, when the elastic piece 43 moves from the second position When the position is switched to the first position, the elastic piece 43 moves axially along the main shaft 20 from the annular groove 413 toward the second friction part 42 and contacts the second friction part 42, and the distance D of the elastic piece 43 moves satisfies the relationship: 0.015mm≤D≤0.025mm; when the elastic piece 43 is switched from the first position to the second position, the elastic piece 43 is located in the annular groove 413 and abuts against the limiting step 414, and the side of the elastic piece 43 and the annular protrusion 411 close to the second friction part 42 remains flush.

[0054] Specifically, in this embodiment, the annular groove 413 provides installation space for the elastic sheet 43, allowing the elastic sheet 43 to be accurately positioned within the first friction part 41. The limiting step 414 further restricts the position of the elastic sheet 43 within the first friction part 41, ensuring that the elastic sheet 43 remains stable within the annular groove 413. This helps improve the accuracy of the brake assembly 40, so that when the hydrostatic spindle mechanism encounters a sudden power outage, the elastic sheet 43 can accurately contact the second friction part 42 to provide stable friction, thereby preventing the spindle 20 from continuing to rotate and effectively avoiding damage to the spindle 20 due to continuous rotation during a power outage.

[0055] Meanwhile, when the hydrostatic spindle mechanism experiences a sudden power outage, the drive assembly 30 stops working. At this time, the control assembly 50 controls the control power supply 51 to be energized according to the stop signal transmitted by the drive assembly 30, so as to control the elastic plate 43 to switch from the second position to the first position and contact the second friction part 42. This causes the second friction part 42 to stop rotating under the friction of the elastic plate 43, thereby stopping the spindle 20 from rotating. This effectively prevents the spindle 20 from dry burning and seizing due to continuous rotation under inertia, and extends the service life of the spindle 20. In addition, when the elastic plate 43 is in the second position in this embodiment, the side of the elastic plate 43 and the annular protrusion 411 close to the second friction part 42 are kept flush. This setting allows the elastic plate 43 to switch from the braking state to the non-braking state, thereby ensuring that the elastic plate 43 can start working from the same initial position every time braking is required, effectively ensuring the consistency of the brake assembly 40.

[0056] Specifically, in this embodiment, the distance D that the elastic sheet 43 moves satisfies the relationship: 0.015mm≤D≤0.025mm. For example, D can be set to 0.015mm, 0.017mm, 0.019mm, 0.02mm, 0.021mm, 0.023mm, 0.025mm, etc. When D is less than 0.015mm, the contact pressure between the elastic plate 43 and the second friction part 42 is insufficient, resulting in a small frictional force. When the hydrostatic spindle mechanism encounters a sudden power failure, the spindle 20 is difficult to stop rotating under the frictional action of the second friction part 42 and the elastic plate 43, thus failing to effectively overcome rotational inertia and causing dry burning and seizure, which in turn leads to serious damage to the spindle 20. When D is greater than 0.025mm, the contact pressure between the elastic plate 43 and the second friction part 42 is too large, resulting in excessive friction between the elastic plate 43 and the second friction part 42, causing the spindle 20 to stop rapidly. This rapid stop will generate a large impact force, which will damage the spindle 20 and the components connected to the spindle 20, reducing the service life of the spindle 20. In other words, in this embodiment, by making the distance D of the elastic sheet 43 move satisfy the relationship: 0.015mm≤D≤0.025mm, it is possible to ensure that there is sufficient contact pressure between the elastic sheet 43 and the second friction part 42, so that the brake assembly 40 can generate sufficient friction force, thereby enabling the main shaft 20 to effectively overcome inertia and stop rotating under the action of friction force, avoiding the impact force and vibration generated by sudden braking.

[0057] Furthermore, the hydrostatic spindle mechanism in this embodiment also includes an accumulator (not shown in the figure). The accumulator is connected to the spindle 20 via a connecting pipe (not shown in the figure) to provide hydraulic oil to the spindle 20 at least. The accumulator has a pressure holding time T1, and the elastic plate 43 of the brake assembly 40 has a braking time T2 when it switches from the second position to the first position. T1 and T2 satisfy the relationship: T1 > T2.

[0058] Specifically, in this embodiment, the hydraulic station continuously supplies hydraulic oil to the spindle 20 during its rotation. When a sudden power outage occurs, the hydraulic station stops supplying oil. At this time, the accumulator continues to supply hydraulic oil to the spindle 20 for a period after the power outage to prevent dry-running if the spindle 20 fails to stop rotating in time due to the power outage. This period of continued hydraulic oil supply is called the accumulator's pressure holding time T1. When T1 < T2, it means that the accumulator's hydraulic oil supply has stopped before the spindle 20 stops rotating. This will cause the spindle 20 to dry-run, resulting in severe wear and shortening its service life. In other words, by ensuring that T1 > T2, this embodiment guarantees that the accumulator provides sufficient hydraulic oil to maintain lubrication during the spindle 20's shutdown process, reducing wear between the spindle 20 and other components and extending the spindle 20's service life to a certain extent.

[0059] Further, see Figure 1 , Figure 3 as well as Figure 4 As shown, the drive assembly 30 in this embodiment includes a pulley 31 and a drive motor 32. The pulley 31 is rotatably fitted onto the outer surface of the outer section 21, and there is a predetermined gap 102 between the pulley 31 and the mounting bracket 11. The drive motor 32 is driven to the pulley 31 via a belt (not shown in the figure) to drive the pulley 31 to rotate, thereby driving the main shaft 20 to rotate. The drive motor 32 is also electrically connected to the control assembly 50.

[0060] Specifically, in this embodiment, the belt has a certain degree of elasticity and flexibility, which can effectively transmit power, thereby driving the main shaft 20 to rotate. Meanwhile, since there is a predetermined gap 102 between the pulley 31 and the mounting bracket 11, this arrangement can isolate and protect the pulley 31, preventing direct contact and friction or collision between the pulley 31 and the mounting bracket 11 during rotation, ensuring the stability of the pulley 31's rotation, and effectively improving the stability and reliability of the drive assembly 30. Furthermore, since the drive motor 32 in this embodiment is electrically connected to the control assembly 50, the control assembly 50 can control the control power supply 51 to be in a powered-on or powered-off state based on the stop or start signal transmitted by the drive motor 32. It is understood that the specific value of the predetermined gap 102 in this embodiment can be set according to the actual processing conditions, and this application does not impose a specific limitation here.

[0061] Further, see Figure 3As shown, the hydrostatic spindle mechanism in this embodiment also includes a bearing assembly 60, which is sleeved on the outer surface of the outer section 21. The bearing assembly 60 includes a bearing retaining sleeve 61 and a rotating bearing assembly 62. The bearing retaining sleeve 61 is sleeved on the outer surface of the outer section 21 and disposed on the housing 10, and the mounting bracket 11 is connected to the bearing retaining sleeve 61. The rotating bearing assembly 62 is disposed between the bearing retaining sleeve 61 and the pulley 31. The rotating bearing assembly 62 includes two bearings 621 spaced apart along the axial direction of the spindle 20. The inner rings of the two bearings 621 are disposed on the bearing retaining sleeve 61, and the outer rings of the two bearings 621 are disposed on the pulley 31.

[0062] Specifically, in this embodiment, the two bearings 621 are spaced apart along the axial direction of the main shaft 20 and located between the bearing retaining sleeve 61 and the pulley 31. This provides a more stable support force for the pulley 31, thereby improving the stiffness of the pulley 31 under tension. The bearing retaining sleeve 61 provides a mounting base for the inner ring of the bearing 621, and the connection between the bearing retaining sleeve 61 and the housing 10 ensures the stability of the entire support structure. Specifically, in this embodiment, the force transmitted from the belt to the pulley 31 is applied to the bearing retaining sleeve 61 through the two bearings 621. The two bearings 621 can withstand a large radial support force, thus greatly reducing the force transmitted from the belt to the pulley 31. The force acting on the bearing retaining sleeve 61 is very small, and since the bearing retaining sleeve 61 is fixed to the housing 10, the force is not transmitted to the main shaft 20, thereby reducing the impact of belt tension on the accuracy of the main shaft 20.

[0063] Specifically, in this embodiment, the bearing fixing sleeve 61 is fixedly connected to the housing 10 and the bearing fixing sleeve 61 is fixedly connected to the mounting bracket 11 by screws or other locking components.

[0064] Furthermore, both bearings 621 in this embodiment include deep groove ball bearings or angular contact ball bearings. Specifically, since deep groove ball bearings can bear radial loads and angular contact ball bearings can bear axial and radial loads, when the spindle 20 experiences radial wobbling due to excessive belt tension, the deep groove ball bearings and angular contact ball bearings can provide stable support for the radial force on the spindle 20, thereby reducing the impact of belt tension on the accuracy of the spindle 20 and effectively ensuring the stability and reliability of the spindle 20's operation.

[0065] Further, see Figure 3As shown, the hydrostatic spindle mechanism in this embodiment further includes an unloading assembly 70. The unloading assembly 70 is sleeved on the outer surface of the outer section 21 and located on the side of the pulley 31 away from the housing 10. The unloading assembly 70 includes an unloading sleeve 71, a connector 72, and an elastic member 73. Specifically, the unloading sleeve 71 is rotatably sleeved on the outer surface of the outer section 21 and connected to the outer section 21. The unloading sleeve 71 is provided with a mounting through hole 711 extending axially along the spindle 20. The connector 72 is disposed in the mounting through hole 711 and connected between the unloading sleeve 71 and the pulley 31. The elastic member 73 is sleeved on the connector 72 and located between the connector 72 and the inner wall surface of the mounting through hole 711. When the drive motor 32 drives the pulley 31 to rotate, the pulley 31 synchronously drives the unloading sleeve 71 to rotate, thereby driving the spindle 20 to rotate. Exemplarily, the connector 72 in this embodiment includes a cylindrical pin.

[0066] Specifically, in this embodiment, since the unloading sleeve 71 is connected to the pulley 31 via the connector 72, and the unloading sleeve 71 is fitted onto the outer surface of the outer section 21 and connected to the outer section 21, when the drive motor 32 starts working, the drive motor 32 drives the pulley 31 to rotate via the belt, thereby driving the unloading sleeve 71 to rotate synchronously, and then driving the main shaft 20 to rotate. In this process, the unloading sleeve 71 plays the role of an intermediate transmission, ensuring that the power of the pulley 31 can be transmitted to the unloading sleeve 71 through the connector 72, and then the power is effectively transmitted to the main shaft 20 via the unloading sleeve 71. Meanwhile, since the elastic element 73 in this embodiment is sleeved on the plug-in 72 and located between the plug-in 72 and the inner wall of the mounting through hole 711, and the elastic element 73 has a buffering effect, when the spindle 20 is radially deformed due to excessive belt tension, the elastic element 73 can absorb part of the force, thereby preventing the force generated by the belt from being directly transmitted to the spindle 20, effectively reducing the vibration generated when the spindle 20 is under force, and ensuring the stability and reliability of the spindle 20.

[0067] Furthermore, in this embodiment, there are multiple mounting through holes 711, which are spaced apart circumferentially along the unloading sleeve 71; there are multiple plug-in members 72, which are disposed one-to-one in the multiple mounting through holes 711; there are multiple elastic members 73, which are sleeved one-to-one on the multiple plug-in members 72 and located between the plug-in members 72 and the inner wall surface of the mounting through holes 711.

[0068] Specifically, in this embodiment, the mounting through hole 711, the connector 72, and the elastic element 73 are all multiple, thus enabling more even power transmission from the pulley 31 to the unloading sleeve 71. When the unloading sleeve 71 is rotated, the multiple connectors 72 work together to evenly distribute the torque onto the unloading sleeve 71, avoiding excessive local stress that might occur due to single-point power transmission. The synergistic effect of the multiple elastic elements 73 absorbs and disperses forces at different locations, reducing the impact of belt tension on the accuracy of the spindle 20 and effectively improving the reliability and stability of the spindle 20. Exemplarily, the elastic element 73 in this embodiment includes an elastic sleeve.

[0069] Optionally, in this embodiment, the mounting through hole 711, the plug-in member 72, and the elastic member 73 can all be set to two, three, or more, and this application does not make specific limitations here.

[0070] As can be seen from the above embodiments, this application utilizes the control power supply 51 to supply power to the brake assembly 40, thereby preventing the spindle 20 from continuing to rotate due to inertia in the event of a sudden power outage. This effectively prevents the spindle 20 from overheating and seizing, and avoids wear on the spindle 20. Simultaneously, during the rotation of the spindle 20, since the control power supply 51 is in a de-energized state, no power is supplied to the brake assembly 40. This prevents the brake assembly 40 from transferring heat to the spindle 20, thus avoiding thermal deformation and effectively ensuring the accuracy of the spindle 20.

[0071] On the other hand, this application also provides a machine tool that includes the aforementioned hydrostatic spindle mechanism. Therefore, this machine tool incorporates all the technical effects of the aforementioned hydrostatic spindle mechanism. Since the technical effects of the hydrostatic spindle mechanism have already been described in detail above, they will not be repeated here.

[0072] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0073] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this application.

[0074] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A hydrostatic spindle mechanism, characterized in that, include: A housing (10) having a receiving cavity (101) and a mounting bracket (11); A main shaft (20) is rotatably disposed within the receiving cavity (101), and the main shaft (20) has an external section (21) extending out of the receiving cavity (101); A drive assembly (30) is driven to connect with the external segment (21) to drive the spindle (20) to rotate about its own axis; A brake assembly (40) is sleeved on the end of the outer segment (21) away from the receiving cavity (101). The brake assembly (40) includes a first friction part (41) and a second friction part (42). The first friction part (41) is disposed on the mounting bracket (11), and the second friction part (42) is disposed on the outer segment (21). The first friction part (41) has an elastic sheet (43). The elastic sheet (43) has a first position that contacts the second friction part (42) to lock the main shaft (20), and a second position that separates from the second friction part (42) to allow the main shaft (20) to rotate. A control component (50) is electrically connected to the drive component (30) and the brake component (40) respectively. The control component (50) controls the elastic sheet (43) to switch between the first position and the second position according to the electrical signal transmitted by the drive component (30).

2. The hydrostatic spindle mechanism according to claim 1, characterized in that, The control component (50) includes: A control power supply (51) is electrically connected to the brake assembly (40). The control power supply (51) has an energized state that controls the elastic sheet (43) to be in the first position and an de-energized state that controls the elastic sheet (43) to be in the second position. The controller (52) is electrically connected to the control power supply (51) and the drive component (30) respectively. The controller (52) controls the control power supply (51) to switch between the power-on state and the power-off state according to the electrical signal transmitted by the drive component (30).

3. The hydrostatic spindle mechanism according to claim 1, characterized in that, The first friction part (41) is provided with an annular protrusion (411), the annular protrusion (411) has a clearance channel (412) for the outer segment (21) to pass through, the annular protrusion (411) and the outer edge of the first friction part (41) are provided with an annular groove (413), and the annular protrusion (411) is provided with a limiting step (414), the limiting step (414) is arranged around the annular protrusion (411) in the circumferential direction, and the elastic sheet (43) is disposed in the annular groove (413) and abuts against the limiting step (414); When the elastic sheet (43) switches from the second position to the first position, the elastic sheet (43) moves axially along the main shaft (20) from the annular groove (413) toward the second friction part (42) and contacts the second friction part (42), and the distance D that the elastic sheet (43) moves satisfies the relationship: 0.015mm≤D≤0.025mm; When the elastic sheet (43) switches from the first position to the second position, the elastic sheet (43) is located in the annular groove (413) and abuts against the limiting step (414), and the side of the elastic sheet (43) and the annular protrusion (411) close to the second friction part (42) remains flush.

4. The hydrostatic spindle mechanism according to claim 1, characterized in that, The hydrostatic spindle mechanism further includes an accumulator, which is connected to the spindle (20) via a connecting pipe to provide hydraulic oil to the spindle (20) at least. The accumulator has a pressure holding time T1, and the elastic plate (43) of the brake assembly (40) has a braking time T2 when it switches from the second position to the first position. T1 and T2 satisfy the relationship: T1 > T2.

5. The hydrostatic spindle mechanism according to claim 1, characterized in that, The driving component (30) includes: A pulley (31) is rotatably fitted onto the outer surface of the outer section (21), and there is a predetermined gap (102) between the pulley (31) and the mounting bracket (11); A drive motor (32) is connected to the pulley (31) via a belt to drive the pulley (31) to rotate and drive the main shaft (20) to rotate. The drive motor (32) is also electrically connected to the control component (50).

6. The hydrostatic spindle mechanism according to claim 5, characterized in that, The hydrostatic spindle mechanism further includes a bearing assembly (60), which is sleeved on the outer surface of the outer section (21). The bearing assembly (60) includes: Bearing retaining sleeve (61), the bearing retaining sleeve (61) is sleeved on the outer surface of the outer section (21) and disposed on the housing (10), the mounting bracket (11) is connected to the bearing retaining sleeve (61); A rotating bearing assembly (62) is disposed between the bearing fixing sleeve (61) and the pulley (31). The rotating bearing assembly (62) includes two bearings (621) spaced apart along the main shaft (20). The inner rings of the two bearings (621) are disposed on the bearing fixing sleeve (61), and the outer rings of the two bearings (621) are disposed on the pulley (31).

7. The hydrostatic spindle mechanism according to claim 6, characterized in that, Both of the bearings (621) comprise either a deep groove ball bearing or an angular contact ball bearing.

8. The hydrostatic spindle mechanism according to claim 5, characterized in that, The hydrostatic spindle mechanism further includes an unloading assembly (70), which is sleeved on the outer surface of the outer section (21) and located on the side of the pulley (31) away from the housing (10). The unloading assembly (70) includes: The unloading sleeve (71) is rotatably sleeved on the outer surface of the outer section (21) and connected to the outer section (21). The unloading sleeve (71) is provided with a mounting through hole (711) extending axially along the main shaft (20). A connector (72) is disposed in the mounting through hole (711) and connected between the unloading sleeve (71) and the pulley (31); An elastic element (73) is sleeved on the plug (72) and located between the plug (72) and the inner wall surface of the mounting through hole (711); When the drive motor (32) drives the pulley (31) to rotate, the pulley (31) synchronously drives the unloading sleeve (71) to rotate, thereby driving the main shaft (20) to rotate.

9. The hydrostatic spindle mechanism according to claim 8, characterized in that, The mounting through holes (711) include a plurality of holes, and the plurality of mounting through holes (711) are arranged at intervals along the circumference of the unloading sleeve (71); The plug-in component (72) includes a plurality of plug-in components (72), and the plurality of plug-in components (72) are disposed in the plurality of mounting through holes (711) in a one-to-one correspondence; The elastic element (73) includes a plurality of elastic elements (73), which are respectively sleeved on a plurality of plug-in elements (72) and located between the plug-in elements (72) and the inner wall surface of the mounting through hole (711).

10. A machine tool, characterized in that, The machine tool includes the hydrostatic spindle mechanism as described in any one of claims 1 to 9.

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