Compact tailstock for machine tools

Abstract

The utility model discloses a compact tailstock for machine tool, including tailstock body and the sleeve of sliding setting on the tailstock body, the left end of sleeve is provided with the mounting hole of installation centre, the right end of sleeve is provided with the hydraulic chamber, installs the piston in the hydraulic chamber, the right end liquid seal of hydraulic chamber is connected with the piston cover, the piston includes the piston rod of liquid seal and goes out the piston cover, and the piston body of fixed connection in the left end of piston rod, the right end detachable connection of tailstock body has the gland, and the piston rod is fixed with the gland, the oil channel no.

Description

Technical Field

[0001] This utility model relates to the field of machine tool equipment technology, and in particular to a compact tailstock for machine tools. Background Technology

[0002] In machining processes, the tailstock of a machine tool, as a key component supporting the workpiece, improving machining rigidity, and ensuring machining accuracy, is widely used in various lathes, grinding machines, and other equipment. The tailstock typically includes a tailstock body and a sleeve (also called a center sleeve) axially movable within the tailstock body. A center is mounted at the front end of the sleeve to clamp the center hole of the workpiece. To achieve automatic clamping and machining cycles, modern CNC machine tools generally use hydraulic drive to push the sleeve axially out or back, completing the clamping and releasing actions on the workpiece. Existing hydraulically driven machine tool tailstocks typically have a hydraulic cylinder chamber within the tailstock body. By introducing pressurized oil into the hydraulic cylinder chamber, a piston is driven to move the sleeve linearly. This structure has advantages such as high output, smooth operation, and ease of automatic control, and has become the mainstream drive method.

[0003] However, existing technologies suffer from the following problems: because the hydraulic drive unit (including hydraulic cylinder, piston, sealing components, and oil circuit interfaces, etc.) needs to be integrated inside the tailstock and directly connected to the sleeve, the sleeve assembly itself integrates the function of the piston rod, resulting in a long axial dimension and a large outer diameter to accommodate the sealing groove and connection structure, making the overall sleeve bulky and heavy. Therefore, how to reduce the size and weight of the sleeve while ensuring hydraulic drive performance, and improve its ease of disassembly and maintenance efficiency, has become an urgent technical problem to be solved in this field. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a compact tailstock for machine tools.

[0005] To solve the above-mentioned technical problems, the technical solution of this utility model is as follows:

[0006] A compact tailstock for a machine tool includes a tailstock body and a sleeve slidably disposed on the tailstock body. The sleeve has a mounting hole for mounting a center at its left end. A hydraulic chamber is provided at the right end of the sleeve, and a piston is installed within the hydraulic chamber. A piston cover is hydraulically sealed to the right end of the hydraulic chamber. The piston includes a piston rod that hydraulically extends through the piston cover and a piston body fixedly connected to the left end of the piston rod. A pressure cap is detachably connected to the right end of the tailstock body, and the piston rod is fixedly connected to the pressure cap. An oil passage 1 and an oil passage 2 are provided within the piston rod. The piston rod and the pressure cap have a hydraulically sealed connection section, and this hydraulically sealed connection section has an annular groove 1 and an annular groove 2. An oil port 1 communicating with an annular groove 1 and an oil port 2 communicating with an annular groove 2 are provided on the pressure cap. One end of oil passage 1 communicates with an annular groove 1, and the other end is located on the right side of the piston body and communicates with the hydraulic chamber. One end of oil passage 2 communicates with an annular groove 2, and the other end is located on the left side of the piston body and communicates with the hydraulic chamber.

[0007] As a preferred technical solution of this utility model, the first oil passage includes an oil passage segment one arranged along the length direction of the piston rod, an oil passage segment two arranged along the radial direction of the piston rod and connected to the first oil passage segment, and an oil passage segment three arranged along the radial direction of the piston rod and connected to the first oil passage segment; the left end of the first oil passage segment extends out of the left end of the piston rod, and a sealing plug is provided at this end.

[0008] As a preferred embodiment of the present invention, the second oil passage includes an oil passage section four arranged along the length of the piston rod, and an oil passage section five arranged radially along the piston rod and connected to the oil passage section four; the left end of the oil passage section four extends out of the left end of the piston rod.

[0009] In one preferred embodiment of this invention, the piston rod and the pressure cap are connected by a thread.

[0010] In one preferred embodiment of this invention, the piston cover and the sleeve are connected by screws.

[0011] As a preferred embodiment of this utility model, the liquid-sealed connection section is sealed with multiple sealing rings, and the piston rod is provided with an installation groove for accommodating the sealing rings; the sealing rings are arranged at intervals with annular groove one and annular groove two.

[0012] As a preferred embodiment of this utility model, a lubricating oil groove is provided on the outer wall of the sleeve, and an oil injection hole communicating with the lubricating oil groove is provided on the tailstock body.

[0013] As a preferred embodiment of this invention, it further includes a base that is detachably connected to the tailstock body.

[0014] The above technical solution has the following advantages:

[0015] This application achieves a high degree of structural and functional integration by directly integrating the hydraulic chamber into the sleeve body, making the sleeve itself a key component of the hydraulic actuator. This design eliminates the need for a separately installed hydraulic cylinder in traditional solutions, avoiding additional installation space requirements and complex connection structures. This effectively shortens the overall axial length of the tailstock, facilitating its layout and installation within limited space and improving the equipment's structural compactness. Crucially, this integrated design achieves this compact layout without significantly increasing the sleeve's axial length. By rationally arranging the internal oil passages and pressure chamber positions, and optimizing wall thickness and strength distribution, the sleeve maintains a relatively compact size while meeting hydraulic drive output requirements. The reduced number of components not only lowers manufacturing costs and assembly difficulty but also facilitates later maintenance and troubleshooting, significantly improving the practicality and maintainability of the tailstock device. Attached Figure Description

[0016] Figure 1 This is a front view of one embodiment of the present utility model;

[0017] Figure 2 for Figure 1 The left view;

[0018] Figure 3 for Figure 2 Sectional view along the middle AA;

[0019] Figure 4 for Figure 3 Enlarged view of section B, with cross-sectional lines omitted;

[0020] Figure 5 for Figure 1 Top view;

[0021] Figure 6 for Figure 1 A three-dimensional image;

[0022] In the picture:

[0023] 1-Tailstock body, 2-Sleeve, 3-Mounting hole, 4-Hydraulic chamber, 5-Piston, 6-Piston cover, 7-Gland, 8-Annular groove one, 9-Annular groove two, 10-Oil port one, 11-Oil port two, 12-Oil passage section one, 13-Oil passage section two, 14-Oil passage section three, 15-Sealing plug, 16-Oil passage section four, 17-Oil passage section five, 18-Sealing ring, 19-Mounting groove, 20-Oil injection hole, 21-Base;

[0024] 51-Piston rod, 52-Piston body. Detailed Implementation

[0025] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings. It should be noted that these descriptions are for the purpose of aiding understanding of this utility model, but do not constitute a limitation thereof. Furthermore, the technical features involved in the various embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0026] Example 1

[0027] As attached Figure 1-6 As shown, a compact tailstock for a machine tool includes a tailstock body 1 and a sleeve 2 slidably disposed on the tailstock body 1. The sleeve 2 has a mounting hole 3 for mounting a center at its left end. A hydraulic chamber 4 is provided at the right end of the sleeve 2, and a piston 5 is installed within the hydraulic chamber 4. A piston cover 6 is hydraulically sealed to the right end of the hydraulic chamber 4. The piston 5 includes a piston rod 51 that hydraulically extends through the piston cover 6, and a piston body 52 fixed to the left end of the piston rod 51. The piston body 52 hydraulically seals against the inner wall of the hydraulic chamber 4. A pressure cap 7 is detachably connected to the right end of the tailstock body 1. The piston rod 51 is fixedly connected to the pressure cap 7; the piston rod 51 has an oil passage 1 and an oil passage 2 inside; the piston rod 51 and the pressure cap 7 have a liquid-sealed connection section, and the liquid-sealed connection section is provided with an annular groove 1 8 and an annular groove 2 9; the pressure cap 7 has an oil port 10 communicating with an annular groove 1 8 and an oil port 2 11 communicating with an annular groove 2 9; one end of the oil passage 1 communicates with an annular groove 1 8, and the other end is located on the right side of the piston body 52 and communicates with the hydraulic chamber 4; one end of the oil passage 2 communicates with an annular groove 2 9, and the other end is located on the left side of the piston body 52 and communicates with the hydraulic chamber 4.

[0028] As a preferred embodiment of this utility model, the first oil passage includes an oil passage section 12 arranged along the length of the piston rod 51, an oil passage section 13 arranged radially along the piston rod 51 and communicating with the first oil passage section 12, and an oil passage section 14 arranged radially along the piston rod 51 and communicating with the first oil passage section 12. The left end of the first oil passage section 12 extends out of the left end of the piston rod 51, and a sealing plug 15 is provided at this end. The second oil passage section 13 is located on the right side of the piston body 52 and communicates with the hydraulic chamber 4. The third oil passage section 14 communicates with the annular groove 8. This structure, by extending the first oil passage section 12 to the left end of the piston rod 51, facilitates drilling the first oil passage section 12 from the end during the machining process, achieving precise positioning and smooth chip removal in deep hole machining, and reducing machining difficulty. The sealing plug 15 ensures the sealing reliability of the first oil passage at the non-connected end, prevents hydraulic oil leakage, and improves system stability.

[0029] As a preferred embodiment of this invention, the second oil passage includes an oil passage section four 16 arranged along the length of the piston rod 51, and an oil passage section five 17 arranged radially along the piston rod 51 and communicating with the oil passage section four 16; the left end of the oil passage section four 16 extends out of the left end of the piston rod 51, and the oil passage section five 17 communicates with the annular groove two 9. This design allows the second oil passage to also have the convenience of introducing the processing path from the left end of the piston rod 51, forming a symmetrical and replicable processing technology with the first oil passage, thus improving production efficiency; at the same time, the independently arranged oil passage section four 16 and oil passage section five 17 ensure the smooth flow of oil return or oil inlet paths, guaranteeing independent oil supply and pressure balance of the oil chambers on both sides of the piston 5, and improving the action response speed and control accuracy.

[0030] As a preferred embodiment of this invention, the piston rod 51 and the pressure cap 7 are connected by a thread. This connection method is simple in structure and easy to install and disassemble, and can achieve reliable axial fixation between the piston rod 51 and the pressure cap 7, effectively transmitting the reaction force under hydraulic action; the threaded connection also has good preload adjustment capability, which helps to improve connection rigidity and vibration resistance, and ensures the running stability of the tailstock in high-frequency reciprocating motion.

[0031] In one preferred embodiment of this invention, the piston cover 6 and the sleeve 2 are connected by screws. This screw connection ensures the piston cover 6 is securely fixed to the right end of the sleeve 2, facilitating the assembly and subsequent maintenance of the hydraulic chamber 4. This connection method ensures uniform force distribution and reliable sealing surface compression, which helps guarantee the sealing performance of the hydraulic chamber 4, prevents high-pressure oil leakage from the connection point, and improves system safety and service life.

[0032] In one preferred embodiment of this invention, the liquid-sealed connection section is sealed with multiple sealing rings 18, and the piston rod 51 is provided with an installation groove 19 for accommodating the sealing rings 18; the sealing rings 18 are spaced apart from the annular groove 8 and the annular groove 9. This sealing structure, by providing a dedicated installation groove 19 on the piston rod 51, ensures accurate positioning and appropriate compression of the sealing rings 18, effectively preventing the sealing rings 18 from being squeezed out or twisted under high-pressure oil. The spaced arrangement of the sealing rings 18 and the annular grooves avoids mutual interference between the sealing area and the oil passage, achieving independent sealing between multiple oil passages, significantly improving the sealing reliability and long-term operational stability of the oil supply system.

[0033] As a preferred embodiment of this invention, a lubricating oil groove (not shown in the figure) is provided on the outer wall of the sleeve 2, and an oil injection hole 20 communicating with the lubricating oil groove is provided on the tailstock body 1. This structure continuously supplies oil to the lubricating oil groove through the external oil injection hole 20, which can form a stable oil film between the sliding mating surfaces of the sleeve 2 and the tailstock body 1, effectively reducing frictional resistance, reducing wear, and extending the service life of the moving parts; at the same time, the lubrication method is simple and reliable, convenient for daily maintenance, and ensures the long-term stability and accuracy of the tailstock.

[0034] As a preferred technical solution of this utility model, it also includes a base 21 that is detachably connected to the tailstock body 1. The detachable connection design of the base 21 facilitates the installation, adjustment and position replacement of the entire tailstock on the machine tool bed, adapting to different workpiece lengths and processing requirements; at the same time, the tailstock can be completely removed during maintenance or replacement, making operation convenient, improving the flexibility and maintenance efficiency of the equipment, and suitable for flexible processing environments with multiple varieties and variable batches.

[0035] The workflow for this application is as follows:

[0036] When it is necessary to retract the sleeve 2 to loosen or replace the workpiece, the hydraulic system introduces pressurized oil through the oil port 10 on the pressure cap 7. The pressurized oil enters the oil passage 1 through the annular groove 8 (the specific path is: oil port 10 → annular groove 8 → oil passage section 3 14 → oil passage section 12 → oil passage section 2 13), and finally injects into the right chamber of the piston body 52 in the hydraulic chamber 4. At this time, the piston body 52 moves to the left under the action of the right-side oil pressure, driving the sleeve 2 to move to the left (retract) synchronously, so that the center is separated from the workpiece; at the same time, the return oil from the left chamber of the piston body 52 in the hydraulic chamber 4 is discharged through the oil passage 2 (the specific path is: left chamber of piston body 52 → oil passage section 5 17 → oil passage section 4 16 → annular groove 2 9 → oil port 2 11), completing the return stroke.

[0037] When it is necessary to clamp the workpiece, the hydraulic system switches the oil circuit, and pressurized oil is introduced through oil port 2 11. The pressurized oil enters oil passage 2 through annular groove 2 9 (path: oil port 2 11 → annular groove 2 9 → oil passage section 4 16 → oil passage section 5 17), and is injected into the left chamber of piston body 52 in hydraulic chamber 4. Under the push of the left oil pressure, piston body 52 moves to the right, driving sleeve 2 to move to the right (extend), so that the center installed in the mounting hole 3 at the left end of sleeve 2 clamps the workpiece; at this time, the oil in the right chamber of piston body 52 is discharged in the reverse direction through oil passage 1 and returns through oil port 10, completing the clamping stroke.

[0038] Throughout the entire movement, the piston rod 51 is fixedly connected to the gland 7 via threads, and the gland 7 is detachably connected to the tailstock body 1. Therefore, the piston rod 51 remains stationary, with only the sleeve 2 and piston body 52 sliding axially relative to the piston rod 51 under hydraulic pressure. The liquid-sealed connection between the piston rod 51 and the gland 7 is reliably sealed by a sealing ring 18 provided on the piston rod 51, preventing hydraulic oil leakage from the movement gap. Simultaneously, oil is supplied to the lubrication groove on the outer wall of the sleeve 2 through the oil injection hole 20 on the tailstock body 1, ensuring smooth sliding of the sleeve 2 within the tailstock body 1 and reducing friction and wear.

[0039] This application achieves a high degree of integration between the drive function and the sleeve 2 body by directly setting the hydraulic chamber 4 at the right end of the sleeve 2 and integrating the piston 5 assembly inside the sleeve 2, thus eliminating the need for a separate hydraulic cylinder in traditional structures. This design fully utilizes the sleeve 2's own structure as a pressure-bearing cavity for the hydraulic actuator, effectively reducing the space occupied by the external hydraulic cylinder, significantly shortening the overall axial structural length of the tailstock, and improving the compactness and space utilization of the machine tool layout.

[0040] In this application, the piston rod 51 is fixed to the pressure cap 7 and remains stationary. Hydraulic oil is supplied to or returned to both sides of the hydraulic chamber 4 through oil passages one and two opened inside the piston rod 51, via oil port 10 and oil port 11 on the pressure cap 7, respectively, realizing dynamic oil supply from a stationary oil circuit to the moving parts. This structure avoids the risks of entanglement, wear, and leakage caused by the reciprocating motion of the external oil pipe with the sleeve 2, and improves the reliability and safety of the system operation.

[0041] In the description of the above embodiments, for the sake of brevity and clarity, some components and their specific structural details that are not directly related to the core innovations of this utility model have been omitted. These omitted parts all fall within the scope of existing technology, and those skilled in the art can fully implement the design and manufacture of these parts based on their professional knowledge and existing technical materials. Therefore, they will not be described in detail here.

[0042] The embodiments of this utility model have been described in detail above with reference to the accompanying drawings, but this utility model is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of this utility model, and these variations still fall within the protection scope of this utility model.

Claims

1. A compact tailstock for a machine tool, comprising a tailstock body (1) and a sleeve (2) slidably disposed on the tailstock body (1), wherein the left end of the sleeve (2) is provided with a mounting hole (3) for mounting a center point; characterized in that: The right end of the sleeve (2) is provided with a hydraulic chamber (4), and a piston (5) is installed in the hydraulic chamber (4). The right end of the hydraulic chamber (4) is hydraulically sealed to a piston cover (6). The piston (5) includes a piston rod (51) that is hydraulically sealed through the piston cover (6), and a piston body (52) fixedly connected to the left end of the piston rod (51). The right end of the tailstock (1) is detachably connected to a pressure cap (7), and the piston rod (51) is fixedly connected to the pressure cap (7). The piston rod (51) has an oil passage one and an oil passage two. The piston rod (51) and the pressure cap (7) are fixedly connected. The gland (7) has a liquid-sealed connection section, and the liquid-sealed connection section is provided with an annular groove one (8) and an annular groove two (9); the gland (7) has an oil port one (10) communicating with an annular groove one (8) and an oil port two (11) communicating with an annular groove two (9); one end of the oil passage one is connected to an annular groove one (8), and the other end is located on the right side of the piston body (52) and is connected to the hydraulic chamber (4); one end of the oil passage two is connected to an annular groove two (9), and the other end is located on the left side of the piston body (52) and is connected to the hydraulic chamber (4).

2. The compact tailstock for machine tools according to claim 1, characterized in that: The first oil passage includes an oil passage section one (12) arranged along the length of the piston rod (51), an oil passage section two (13) arranged radially along the piston rod (51) and communicating with the first oil passage section (12), and an oil passage section three (14) arranged radially along the piston rod (51) and communicating with the first oil passage section (12); the left end of the first oil passage section (12) extends out of the left end of the piston rod (51), and a sealing plug (15) is provided at this end.

3. The compact tailstock for machine tools according to claim 1 or 2, characterized in that: The second oil passage includes an oil passage section four (16) arranged along the length of the piston rod (51) and an oil passage section five (17) arranged radially along the piston rod (51) and connected to the oil passage section four (16); the left end of the oil passage section four (16) extends out of the left end of the piston rod (51).

4. The compact tailstock for machine tools according to claim 1 or 2, characterized in that: The piston rod (51) and the gland (7) are connected by threads.

5. The compact tailstock for machine tools according to claim 1 or 2, characterized in that: The piston cap (6) and the sleeve (2) are connected by screws.

6. The compact tailstock for machine tools according to claim 1 or 2, characterized in that: The liquid-sealed connection section is sealed with multiple sealing rings (18), and the piston rod (51) is provided with an installation groove (19) for accommodating the sealing rings (18); the sealing rings (18) are arranged at intervals with annular groove one (8) and annular groove two (9).

7. The compact tailstock for machine tools according to claim 1 or 2, characterized in that: The sleeve (2) has a lubricating oil groove on its outer wall, and the tailstock (1) has an oil injection hole (20) that communicates with the lubricating oil groove.

8. The compact tailstock for machine tools according to claim 1 or 2, characterized in that: It also includes a base (21) that is detachably connected to the tailstock body (1).

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