Numerical control lathe tool rest and spindle in-place reliability test system based on bidirectional dynamic load simulation loading

Abstract

The application discloses a numerical control lathe tool rest and spindle in-place reliability test system based on bidirectional dynamic load simulation loading, which comprises a lathe bed, a sliding block table, a tool rest part, a machine tool spindle, a dynamic load generating device, a dynamic load loading support device and a six-degree-of-freedom platform. The dynamic load generating device comprises a threaded loading head, a No.1 force sensor, a No.1 flexible body, a linear motor core, a No.2 flexible body, a No.2 force sensor and a ball groove loading head, which are sequentially connected. The load loading part can realize dynamic and static cutting force simulation loading, and the dynamic and static cutting load size and frequency can be changed by controlling the displacement and speed of the linear motor. Meanwhile, the dynamic and static cutting load amplitude and loading frequency can be changed by replacing the flexible body made of different materials, and the system has high flexibility.

Description

Technical Field

[0001] This invention relates to a testing device for the reliability of key functional components of CNC machine tools. More specifically, this invention relates to an in-situ reliability testing system capable of simulating dynamic and static cutting loads on the tool post and spindle functional components of CNC machine tools. Background Technology

[0002] In recent years, with the rapid development of the equipment manufacturing industry, my country has become a major producer and user of CNC machine tools. Currently, domestically developed CNC machine tools have made significant progress in precision, speed, size, and multi-axis linkage. However, with the increase in functions, potential failures have also increased, and advanced functions and performance indicators cannot be maintained, leading to serious reliability issues. This has become a focus of attention for enterprises, users, and the sales market, and a bottleneck for the development of the CNC machine tool industry. One of the main reasons for the low reliability level of domestically produced CNC machine tools is the low reliability level of key functional components. Therefore, researching and developing in-situ reliability testing devices and technologies for key functional components of CNC machine tools is crucial. Conducting reliability tests can fully stimulate and expose potential failures, providing fundamental data for exploring failure mechanisms and conducting reliability assessments, which has significant theoretical research value and engineering application value. The tool post and spindle, as key functional components of high-end CNC lathes, have a significant impact on the overall reliability of the machine.

[0003] my country's research on reliability testing of key functional components of CNC machine tools started relatively late. At present, there are only reliability testing devices for single key functional components of machine tools, and there is no reliable testing device or system that can simultaneously conduct on-site reliability testing on two or more key functional components of machine tools and simulate actual working conditions and load loading. Summary of the Invention

[0004] The purpose of this invention is to solve the above problems and provide a CNC lathe tool post and spindle in-situ reliability test system based on bidirectional dynamic load simulation.

[0005] A CNC lathe tool post and spindle in-situ reliability testing system based on bidirectional dynamic load simulation includes:

[0006] Lathe bed 104, slide table 103, tool post 5, machine tool spindle 201, dynamic load generating device, dynamic load loading support device, and load-bearing part 4;

[0007] The tool holder 5 is mounted on the slide table 103, which slides on the lathe bed 104 via the X guide rail 101 and the Y guide rail 102.

[0008] The machine tool spindle 201 is axially connected to the lathe bed 104. The machine tool spindle 201 is equipped with a chuck 202, a ball joint seat 203, and a ball joint 204.

[0009] The dynamic load loading support device includes: a support base 311, a guide rod 316 (No. 1), and a guide rod 322 (No. 2). The support base 311 is installed above the bearing part 4, and the bearing part 4 is installed on the lathe bed 104. The guide rods 316 (No. 1) and 322 (No. 2) are fixed at both ends to the support base 311.

[0010] The dynamic load generating device includes a threaded loading head 301, a force sensor 303, a flexible body 317, a linear motor stator 319, a flexible body 318, a force sensor 304, and a ball groove loading head 302, which are connected in sequence.

[0011] The linear motor stator 319 is sleeved on both sides of the guide rod 316 and the guide rod 322, and the linear motor stator is mounted on the support base 311;

[0012] The threaded loading head 301 is connected to the ball joint 204.

[0013] The flexible body is a spring body, and there are interlocking telescopic guide rods at the axis of the spring body.

[0014] The left end of the threaded loading head 301 is threadedly connected to the ball hinge 204, and the right end of the threaded loading head 301 is threadedly connected to the No. 1 force sensor 303; the thread on the left end of the threaded loading head 301 is larger than the thread on the right end.

[0015] The linear motor stator 319 has two symmetrically arranged control sleeves at both ends; the control sleeves are used to adjust the length of the dynamic load generating device.

[0016] The dynamic load generating device is equipped with force transmission rods between its components, and the force transmission rods are axially connected to the support base 311.

[0017] The tool holder part 5 is provided with a simulated cutting tool bar 501, and the loading part is a ball, which corresponds to the ball groove of the loading part of the ball groove loading head 302.

[0018] The load-bearing part 4 is a six-degree-of-freedom platform.

[0019] The load-bearing part 4 includes a rotating plate 401, a six-degree-of-freedom platform base plate 402, a six-degree-of-freedom platform top plate 403, an inner thrust rod 404, an outer thrust rod 405, a drive motor 406, a hydraulic pump 407, a hydraulic thrust rod 408, a moving slot plate 409, a connecting bearing 410, a rotating shaft 411, a No. 1 fastening bolt 412, a No. 2 fastening bolt 413, and a No. 3 fastening bolt 414;

[0020] The rotating plate 401 is a circular plate-shaped structural component. Two strip-shaped through holes are opened on both sides of the rotating plate 401. The middle part of the two strip-shaped through holes is rectangular and the two sides are arc-shaped, which are used to connect with the support base 311 by bolts. Six threaded through holes are evenly distributed in the center of the rotating plate 401 for bolt connection with the top plate 403 of the six-degree-of-freedom platform.

[0021] This invention provides an in-situ reliability testing system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation. It includes: lathe bed 104, slide table 103, tool post 5, machine tool spindle 201, dynamic load generating device, dynamic load loading support device, and six-degree-of-freedom platform. The dynamic load generating device includes: a threaded loading head 301, a first force sensor 303, a first flexible body 317, a linear motor stator 319, a second flexible body 318, a second force sensor 304, and a ball groove loading head 302, which are connected in sequence.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] 1. The in-situ reliability testing system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation described in this invention is a reliability testing system capable of simultaneously applying simulated actual working condition loads to two key functional components, the machine tool tool post and spindle, in-situ. The load loading section can simultaneously simulate applying dynamic and static cutting loads to both functional components, providing a testing system solution for conducting reliability tests with simulated actual working condition load loading.

[0024] 2. The load loading part of the CNC lathe tool post and spindle in-situ reliability test system based on bidirectional dynamic load simulation loading described in this invention can realize dynamic and static cutting force simulation loading. By controlling the displacement and speed of the linear motor, the magnitude and frequency of dynamic and static cutting loads can be changed. At the same time, the amplitude and loading frequency of dynamic and static cutting loads can be changed by replacing the flexible body with a different material, which has high flexibility.

[0025] 3. The in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation described in this invention does not require a separate test environment and can perform in-situ reliability tests on existing CNC lathes, reducing the complexity of CNC machine tool reliability tests and demonstrating the versatility of this test system. Attached Figure Description

[0026] The invention will now be further described with reference to the accompanying drawings:

[0027] Figure 1 This is an isometric projection of the in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation, as described in this invention.

[0028] Figure 2 This is an isometric projection of the connection state between the load loading part and the spindle part in the in-situ reliability test system of CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading as described in this invention.

[0029] Figure 3 This is an isometric projection of the connection state between the load loading part and the tool holder part in the in-situ reliability test system of CNC lathe tool holder and spindle based on bidirectional dynamic load simulation loading as described in this invention.

[0030] Figure 4 This is an isometric projection of the load-bearing and loading parts in the in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading as described in this invention.

[0031] Figure 5 This is an isometric projection of the loading part of the in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading as described in this invention.

[0032] Figure 6 This is an isometric projection of the load-bearing part in the in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading as described in this invention.

[0033] Figure 7 This is an exploded isometric projection of the connection between the loading part and the bearing part in the in-situ reliability test system of CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading as described in this invention.

[0034] Figure 8 This is an exploded isometric projection of the loaded part (excluding the central part) in the in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading as described in this invention.

[0035] Figure 9 This is an exploded isometric projection of the central part of the loading section of the in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading as described in this invention.

[0036] (In the diagram: 1. Lathe base, 2. Spindle, 3. Load loading section, 4. Bearing section, 5. Tool post. 101. X-axis guide rail, 102. Y-axis guide rail, 103. Slider table, 104. Lathe bed, 201. Machine spindle, 202. Chuck, 203. Ball joint seat, 204. Ball joint, 301. Threaded loading head, 302. Ball groove loading head, 303. Force sensor #1, 304. Force sensor #2, 305. Bearing seat #1, 306. Bearing seat #2, 307. Control sleeve #1, 308. Control sleeve #2, 309. Force transmission rod #1, 310. Force transmission rod #2, 311. Support base, 312. Side plate #1, 313. Side plate #2, 314. Connecting rod seat #1, 315. Connecting rod seat #2, 3...) 16.1 Guide rod, 317.1 Flexible body, 318.2 Flexible body, 319. Linear motor stator, 320.1 Motor baffle, 321.2 Motor baffle, 322.2 Guide rod, 323.1 Bearing, 324.2 Bearing, 401. Rotating plate, 402. Six-degree-of-freedom platform base plate, 403. Six-degree-of-freedom platform top plate, 404. Internal thrust rod, 405. External thrust rod, 406. Drive motor, 407. Hydraulic pump, 408. Hydraulic thrust rod, 409. Moving slot plate, 410. Connecting bearing, 411. Rotating shaft, 412.1 Fastening bolt, 413.2 Fastening bolt, 414.3 Fastening bolt, 501. Simulated cutting tool holder, 502. CNC tool holder, 503. Simulated cutting tool holder. Detailed Implementation

[0037] The present invention will now be described in detail with reference to the accompanying drawings:

[0038] See Figure 1 The in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading described in this invention consists of a lathe base part (1), a spindle part (2), a load loading part (3), a load-bearing part (4), and a tool post part (5).

[0039] I. Lathe Section

[0040] The lathe base 1 includes an X-axis guide rail 101, a Y-axis guide rail 102, a slide table 103, and a lathe bed 104.

[0041] The X-axis guide rail 101 is a sliding or rolling guide rail, fastened to the machine body with bolts. The Y-axis guide rail 102 is also a sliding or rolling guide rail. Four sliders are fixed to the bottom surface of the slide block 103 to cooperate with the Y-axis guide rail 102, and the upper surface of the slide block 103 is fastened to the tool holder 502 with bolts. The lathe bed 104 is the body component of the CNC lathe. The upper end of the lathe bed 104 has a boss for mounting the X-axis guide rail 101, a platform on the left end for mounting the machine tool spindle 201, and a pair of guide rails in the middle for mounting the tailstock of the CNC lathe.

[0042] II. Spindle Section

[0043] See Figure 1 and Figure 2 The spindle part 2 includes a machine tool spindle 201, a chuck 202, a ball joint seat 203, and a ball joint 204.

[0044] The machine tool spindle 201 is the workpiece clamping spindle of a CNC lathe, and can be a mechanical spindle or an electric spindle. The lower end of the machine tool spindle 201 is fixedly connected to the bed 104 by bolts. A chuck 202 is fixedly installed on the front right end of the machine tool spindle 201. The chuck 202 can be a three-jaw chuck or a four-jaw chuck. The left cylindrical end of the ball joint seat 203 is clamped at the front right end of the chuck 202. The ball joint seat 203 has a cylindrical structure, and a spherical groove in the front right end of the ball joint seat 203 is used to connect the ball joint 204. The left cylindrical end of the ball joint seat 203 is clamped and fixed by the chuck 202. The right end of the ball joint 204 is a column with external threads, which form a threaded connection with the internal threads of the threaded loading head 301. The annular rib in the middle of the ball joint 204 is used to prevent the threaded connection between the ball joint 204 and the threaded loading head 301 from loosening.

[0045] III. Loading Section

[0046] See Figure 1-5 , Figure 8 and Figure 9 The load loading section 3 is divided into a dynamic load generating device and a dynamic load loading support device.

[0047] 1. Dynamic load loading support device

[0048] See Figure 4 , Figure 5 , Figure 8 and Figure 9 The dynamic load loading support device consists of a support base 311, bearing seat 1 305, bearing seat 2 306, bearing 1 323, bearing 2 324, motor baffle 1 320, motor baffle 2 321, side plate 1 312, side plate 2 313, guide rod 1 316, and guide rod 2 322.

[0049] The support base 311 is a rectangular plate structure. Four evenly distributed threaded holes are drilled at both the front and rear ends of the support base 311 for connection with bearing housing 305 (No. 1) and bearing housing 306 (No. 2). A groove is drilled in the middle of each of the four threaded holes to mate with the bottom bosses of bearing housing 305 and bearing housing 306. A rectangular through-hole is drilled at a certain distance from both the front and rear sides of the support base 311; the through-hole is rectangular in the middle and arc-shaped on both sides, for fastening to the rotating plate 401 with bolts. Two rectangular grooves are located at a certain distance inside the two rectangular through-holes of the support base 311 to mate with the bosses of motor baffle 320 (No. 1) and motor baffle 321 (No. 2), respectively, and threaded holes are drilled for fastening the motor baffles 320 and 321. Several rectangular bosses of a certain height are located at the upper middle part of the support base 311; the gaps between the rectangular bosses are for installing the wires of the drive linear motor stator 319.

[0050] The bearing housings 305 (No. 1) and 306 (No. 2) have identical structures, both being plate-shaped components with a semi-circular upper end and a rectangular lower end. Both bearing housings 305 and 306 have through holes drilled in the upper part for interference fit with bearings 323 (No. 1) and 324 (No. 2). At a certain distance from the bottom surface, the lower ends of both bearing housings 305 and 306 have two side plates with threaded through holes for fastening to the support base 311. Bearings 323 (No. 1) and 324 (No. 2) are standard bearings. Bearings 323 and 324 are respectively interference-fitted with the through holes of bearing housings 305 and 306. After the bearings are fitted and the bearing housings are fixed, bearings 323 and 324 should remain concentric.

[0051] The No. 1 motor baffle 320 and the No. 2 motor baffle 321 have the same structure, both being rectangular plate-type structural components. The upper part of the No. 1 motor baffle 320 and the No. 2 motor baffle 321 has three circular through holes. The middle through hole is larger and is used for clearance fit with the No. 1 connecting rod seat 314. The circular through holes on both sides are smaller and are used for clearance fit with the No. 1 guide rod 316 and the No. 2 guide rail 322. There are six threaded holes evenly distributed on both sides of the No. 1 motor baffle 320 and the No. 2 motor baffle 321 for threaded connection of the No. 1 side plate 312 and the No. 2 side plate 313. At a distance from the bottom of the No. 1 motor baffle 320 and the No. 2 motor baffle 321, there are six evenly distributed side plates. Each side plate has four through holes for bolt fasteners to fix the No. 1 motor baffle 320 and the No. 2 motor baffle 321 to the support base 311. The protrusions at the lower ends of motor baffle 320 and motor baffle 321 are used for transitional engagement with the grooves on the support base 311.

[0052] The No. 1 side plate 312 and No. 2 side plate 313 are U-shaped plate structures. A rectangular through hole is opened at the lower right end of each side plate 312 and No. 2 side plate 313 for the inlet and outlet of the drive wire. Each of the front and rear surfaces of each side plate 312 and No. 2 side plate 313 has a circular through hole. Each set of circular through holes is adapted to the threaded holes on the end faces of the No. 1 motor baffle 320 and No. 2 motor baffle 321 for the connection of threaded fasteners. The No. 1 guide rod 316 and No. 2 guide rod 322 are cylindrical structural components. The diameter of the circular cross-section of the No. 1 guide rod 316 and No. 2 guide rod 322 is the same as the diameter of the through holes on both sides of the No. 1 motor baffle 320 and No. 2 motor baffle 321, and their length is the same as the distance between the two inner cross-sections of the No. 1 side plate 312 and No. 2 side plate 313.

[0053] 2. Dynamic load loading device

[0054] See Figure 5 , Figure 8 and Figure 9 The dynamic load loading device includes a threaded loading head 301, a ball groove loading head 302, a force sensor 1 303, a force sensor 2 304, a distance control sleeve 1 307, a distance control sleeve 2 308, a connecting rod seat 1 314, a flexible body 1 317, a flexible body 2 318, and a linear motor stator 319.

[0055] See Figure 1 , Figure 2 and Figure 3 The threaded loading head 301 has a cylindrical structure and high rigidity, resulting in minimal deformation under heavy loads. A larger threaded hole at the left end of the threaded loading head 301 is used for threaded connection with the external thread at the right end of the ball joint 204. A smaller threaded hole at the right end of the threaded loading head 301 is used for threaded connection with force sensor 303 (No. 1). The ball groove loading head 302 has the same structure as the threaded loading head 301. A spherical groove at the right end of the ball groove loading head 302 mates with the simulated cutting tool holder 501, transmitting dynamic force to the simulated cutting tool holder 501. A threaded hole at the left rear end of the ball groove loading head 302 is used for connection with force sensor 304 (No. 2). The No. 1 force sensor 303 and the No. 2 force sensor 304 have the same structure. Both ends of the No. 1 force sensor 303 and the No. 2 force sensor 304 have protruding threaded post portions for connection with the threaded loading head 301, the ball groove loading head 302, the No. 1 force transmission rod 309 and the No. 2 force transmission rod 310. The No. 1 force sensor 303 and the No. 2 force sensor 304 have large rigidity.

[0056] Since the dynamic load loading device has a symmetrical structure on both sides except for the loading head and is made of the same material, only the left side structure will be described below.

[0057] The first force transmission rod 309 is rod-shaped with high rigidity. A threaded hole is located at the left front end of the first force transmission rod 309 for connection to the first force sensor 303. An external thread structure is present on the cylindrical surface of the right rear end of the first force transmission rod 309 for connection to the first distance control sleeve 307. The first distance control sleeve 307 is a cylindrical rigid structure. Four straight grooves are cut along four perpendicular directions in the middle portion of the first distance control sleeve 307 to facilitate external clamping and rotation. Two threaded holes with opposite thread directions are located at each end of the first distance control sleeve 307 for connection to the first force transmission rod 309 and the first connecting rod seat 314. Rotating the first distance control sleeve 307 adjusts the extension and retraction of the first force transmission rod 309, thereby controlling the distance between the threaded loading head 301 and the linear motor stator 319. To ensure a tighter threaded connection, two nuts can be added to both sides of the first distance control sleeve 307 for anti-loosening design.

[0058] The No. 1 connecting rod seat 314 is a cylindrical rigid structure, divided into three parts. The front end is a solid cylindrical rigid structure, and the outer surface of the left end of the No. 1 connecting rod seat 314 has external threads for threaded connection with the No. 1 control sleeve 307. The rear end of the No. 1 connecting rod seat 314 has a cylindrical design to facilitate the installation of the flexible body. The center of the right rear end of the No. 1 connecting rod seat 314 has a relatively thin cylindrical rod for cooperation and guidance with the linear motor stator 319. The corresponding No. 1 flexible body 317 is a flexible ring structure (this invention patent takes a spring as an example). The two ends of the No. 1 flexible body 317 are planar ring structures for cooperation and connection with the No. 1 connecting rod seat 314 and the linear motor stator 319. The linear motor stator 319 is a rectangular plate structure. Two circular through holes are opened at each end of the linear motor stator 319 to cooperate with guide rod 316 (No. 1) and guide rod 322 (No. 2) for movement in the correct direction. A large permanent magnet is filled in the center of the linear motor stator 319 for driving the motor's motion. Two cylindrical structures are located at the left and right ends of the linear motor stator 319 to cooperate with flexible body 317 (No. 1) and flexible body 318 (No. 2). A smaller cylindrical structure is located at the center of the front and rear ends of the linear motor stator 319 to cooperate with connecting rod seat 314 (No. 1) and connecting rod seat 315 (No. 2) and provide guidance.

[0059] IV. Load-bearing components

[0060] See Figure 4 , Figure 6 and Figure 7The supporting part 4 includes a rotating plate 401, a six-degree-of-freedom platform base plate 402, a six-degree-of-freedom platform top plate 403, an inner thrust rod 404, an outer thrust rod 405, a drive motor 406, a hydraulic pump 407, a hydraulic thrust rod 408, a moving slot plate 409, a connecting bearing 410, a rotating shaft 411, a No. 1 fastening bolt 412, a No. 2 fastening bolt 413, and a No. 3 fastening bolt 414.

[0061] The rotating plate 401 is a circular plate-shaped structural component. Two strip-shaped through holes are formed on both sides of the rotating plate 401. The middle portion of the two strip-shaped through holes is rectangular, and the two sides are arc-shaped, for bolt connection with the support base 311. Six threaded through holes are evenly distributed in the center of the rotating plate 401 for bolt connection with the six-degree-of-freedom platform top plate 403. At the very center of the rotating plate 401 is a circular through hole with the same diameter as the outer diameter of the connecting bearing 410. This circular through hole is interference-fitted with the connecting bearing 410. A strip-shaped through hole is radially located on the side of the rotating plate 401. After mating with the support base 311 and the six-degree-of-freedom platform top plate 403, the strip-shaped through hole of the rotating plate 401 exposes the scale lines of the six-degree-of-freedom platform top plate 403 below, for adjusting the angle of the upper linear motor. The six-degree-of-freedom platform top plate 403 is a circular plate-shaped structural component. Three evenly distributed bosses are located on the bottom of the top plate 403, each with two threaded holes for fastening the plug. At the very center of the top plate 403 is a cylindrical through-hole with the same diameter as the maximum cylindrical diameter of the rotating shaft 411, and it is interference-fitted with the maximum cylindrical portion of the rotating shaft 411. Around the central through-hole, the top plate 403 has three arc-shaped strip-shaped through-holes for bolting the rotating plate 401 to fastening bolts 412, 413, and 414. The connecting bearing 410 is coaxially fitted with the through-holes of the rotating shaft 411 and the rotating plate 401, and the connecting bearing 410 is interference-fitted with the through-hole of the rotating plate 401. The shoulder of the rotating shaft 411 is interference-fitted with the central through-hole of the top plate 403. In the device that connects the supporting base 311 and the rotating plate 401 with the connecting bearing 410, the rotating shaft 411 and the six-degree-of-freedom platform top plate 403, the rotating plate 401 can rotate around the rotating shaft 411 to adjust its direction, and its position is fixed by three bolts: fastening bolt 1 412, fastening bolt 2 413 and fastening bolt 3 414.

[0062] (Since the six drive devices of the six-degree-of-freedom platform are identical, this invention briefly describes the structure of one of the drive devices.) The inner thrust rod 404 is a cylindrical structure with an annular insertion hole at its upper end. This insertion hole connects the inner thrust rod 404 to the top plate 403 of the six-degree-of-freedom platform via a pin connection device. The inner thrust rod 404 uses a ball screw structure to control its rising height (suitable for linear motor drives; hydraulic devices require an oil tank). The outer thrust rod 405 is a cylindrical structure welded to a flat plate, internally cooperating with the inner thrust rod 404. The lower end of the outer thrust rod 405 is threadedly connected to the bottom plate 402 of the six-degree-of-freedom platform via an insertion hole on the flat plate. The lower end of the outer thrust rod 405 is connected to the drive motor 406 through an opening to ensure the drive motor 406 operates normally and pushes the inner thrust rod 404. The drive motor 406 is a stepper motor, which drives and controls the height of the inner thrust rod 404. The drive motor 406 is welded and fastened to the plate attached to the outer thrust rod 405. The six-degree-of-freedom platform base plate 402 is a plate-shaped structural component, welded from an upper plate and a lower end slot plate. The upper end plate of the six-degree-of-freedom platform base plate 402 has three bosses evenly distributed on its upper end surface. Each boss has three threaded holes on its side for fastening the plug and connecting with the outer thrust rod 405. The lower end slot plate of the six-degree-of-freedom platform base plate 402 has a relatively thick rib on one side. One side of the rib is used to support the L-shaped plate of the lathe bed 104. The rib has four threaded holes in two parts for connecting with the hydraulic pump 407. The other side of the lower end slot plate of the six-degree-of-freedom platform base plate 402 has a T-shaped groove with a certain distance at its upper end to guide the movement of the moving slot plate 409. The hydraulic pump 407 and hydraulic thrust rod 408 are hydraulic devices. All four hydraulic devices in this patent are identical; only one is described here. The bottom of the hydraulic pump 407 has a flat plate with through holes at each of its four corners for threaded connection with threaded holes on the ribs of the six-degree-of-freedom platform base plate 402. The head of the hydraulic thrust rod 408, furthest from the hydraulic pump 407, has a rubber sleeve structure for better pushing of the moving slot plate 409. The moving slot plate 409 is an L-shaped plate structure with its upper end cut into a T-shape to engage with the six-degree-of-freedom platform base plate 402 and facilitate movement. The hydraulic thrust rod 408 applies positive pressure to the moving slot plate 409, causing the moving slot plate 409 and the six-degree-of-freedom platform base plate 402 to be fixed to the inverted L-shaped guide plate of the lathe bed 104 through friction.

[0063] V. Tool Holder

[0064] See Figure 1 and Figure 3 The tool holder section includes a simulated cutting tool holder 501, a CNC tool holder 502, and a simulated cutting tool holder 503.

[0065] The cutting simulation tool holder 501 is a rod-like structure with a circular cross-section. One end of the simulation cutting tool holder 501 is integrated with a sphere. The cutting simulation tool holder 501 is mounted on the simulation cutting tool holder 503, and the two are mounted together on the tool head of the CNC tool holder 502 to perform reliability testing in place of a cutting tool.

[0066] The bottom of the CNC tool holder 502 is fixedly connected to the slide table 103 by bolts.

[0067] Working principle of in-situ reliability testing system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation:

[0068] See Figure 1 The figure shows a schematic diagram of the installation of the CNC lathe tool post and spindle in-situ reliability test system based on bidirectional dynamic load simulation. Before the test begins, the flexible body is selected according to the magnitude and frequency of the dynamic and static cutting loads in the simulated working conditions. Next, the bearing part 4 and the load loading part 3 need to be assembled. Then, the ball hinge and its base are connected to the threaded loading head 301 through threads. Then, the bearing part 4 and the load loading part 3 are fixed to the bed by friction through the bed guide rail and the hydraulic device at the bottom of the bearing part 4. Next, the six-degree-of-freedom platform and the rotary plate 401 are adjusted to the position to be tested. The ball hinge seat 203 is clamped using the chuck 202. Finally, the CNC tool post 502 is adjusted so that the spherical head of the simulated cutting tool bar 501 is engaged with the ball groove loading head 302.

[0069] The in-situ reliability testing system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation described in this invention applies an initial force to the ball groove loading head 302 when conducting reliability tests on the spindle 201 and CNC tool post 502 of the machine tool under test. The CNC system of the CNC lathe controls the simulated cutting tool bar 501 of the CNC tool post 502 to apply an initial force to the ball groove loading head 302. The initial force is related to the average value of the dynamic force; the larger the average value, the larger the initial force. The magnitude of the initial force can be directly read through force sensor 1 303 and force sensor 2 304. Then, a certain frequency of alternating current is passed through the wires in the gap between the intermediate bosses of the support base 311 to drive the stator 319 of the linear motor to perform reciprocating micro-movements. At this time, due to its material and dynamic characteristics, the flexible body will output dynamic force to the loading heads at both ends and act on the machine tool spindle 201 and CNC tool post 502 respectively.

Claims

1. An in-situ reliability testing system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation, comprising: Lathe bed (104), slide table (103), tool post (5), machine tool spindle (201), dynamic load generating device, dynamic load loading support device, and load-bearing part (4). The tool holder (5) is mounted on the slide table (103), and the slide table (103) slides on the lathe bed (104) via the X guide rail (101) and the Y guide rail (102); The machine tool spindle (201) is axially connected to the lathe bed (104), and the machine tool spindle (201) is provided with a chuck (202), a ball joint seat (203), and a ball joint (204). The dynamic load loading support device includes: a support base (311), a guide rod 1 (316), and a guide rod 2 (322). The support base (311) is installed above the bearing part (4), and the bearing part (4) is installed on the lathe bed (104). The two ends of the guide rod 1 (316) and the guide rod 2 (322) are fixed on the support base (311). The dynamic load generating device includes a threaded loading head (301), a force sensor (303), a flexible body (317), a linear motor stator (319), a flexible body (318), a force sensor (304), and a ball groove loading head (302), which are connected in sequence. The linear motor stator (319) is sleeved on both sides of the guide rod (316) and the guide rod (322), and the linear motor stator (319) is mounted on the support base (311); The threaded loading head (301) is connected to the ball joint (204).

2. The in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading as described in claim 1, characterized in that: The flexible body is a spring body, and nested telescopic guide rods are provided at the axis of the spring body.

3. The in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading according to claim 1 or 2, characterized in that: The left end of the threaded loading head (301) is threadedly connected to the ball hinge (204), and the right end of the threaded loading head (301) is threadedly connected to the No. 1 force sensor (303); the thread on the left end of the threaded loading head (301) is larger than the thread on the right end.

4. The in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading as described in claim 3, characterized in that: The linear motor stator (319) is provided with two symmetrical control sleeves at both ends; the control sleeves are used to adjust the length of the dynamic load generating device.

5. The in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading according to claim 4, characterized in that: The dynamic load generating device is equipped with force transmission rods between its components, and the force transmission rods are axially connected to the support base (311).

6. The in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading according to claim 4 or 5, characterized in that: The tool holder part (5) is provided with a simulated cutting tool bar (501), and the loading part is a ball, which corresponds to the ball groove of the loading part of the ball groove loading head (302).

7. The in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading according to claim 6, characterized in that: The load-bearing part (4) is a six-degree-of-freedom platform.

8. The in-situ reliability test system for CNC lathe tool post and spindle based on bidirectional dynamic load simulation loading according to claim 7, characterized in that: The load-bearing part (4) includes a rotating plate (401), a six-degree-of-freedom platform base plate (402), a six-degree-of-freedom platform top plate (403), an inner thrust rod (404), an outer thrust rod (405), a drive motor (406), a hydraulic pump (407), a hydraulic thrust rod (408), a moving slot plate (409), a connecting bearing (410), a rotating shaft (411), a No. 1 fastening bolt (412), a No. 2 fastening bolt (413), and a No. 3 fastening bolt (414); The rotating plate (401) is a circular plate-shaped structural component. Two strip-shaped through holes are opened on both sides of the rotating plate (401). The middle part of the two strip-shaped through holes is rectangular and the two sides are arc-shaped, which are used for bolt connection with the support base (311). Six threaded through holes are evenly distributed in the center of the rotating plate (401) for bolt connection with the top plate (403) of the six-degree-of-freedom platform.

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