Long-wheelbase part machining clamp
By designing a mainboard that connects the four axes to the tailstock, and combining it with clamping, support, and limiting components, the problems of unstable clamping and difficulty in ensuring accuracy during the machining of long-axis parts were solved, achieving high-precision and safe machining results.
Patent Information
- Application Number
- CN202511193024.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-25
- Publication Date
- 2025-11-25
AI Technical Summary
Existing machining fixtures are difficult to adapt to parts with long wheelbases and special structures at the far end, resulting in poor clamping stability and difficulty in ensuring machining accuracy, especially in terms of machining cylindricity and coaxiality, which have out-of-tolerance problems.
The mainboard design, which connects the four axes to the tailstock, combines clamping, support and limiting components. It uses three equidistant support surfaces and triangularly distributed clamping cylinders for clamping. With the help of floating support cylinders and hydraulic sequence valves, it achieves stable clamping and precise positioning of parts. Real-time monitoring and adjustment are achieved through contour limit blocks and airtight anti-misalignment holes.
It improves the positioning accuracy and clamping stability of long-axis parts, reduces displacement deformation and vibration during processing, ensures cylindricity and coaxiality accuracy, avoids processing errors and safety risks, and improves processing efficiency and equipment operation stability.
Smart Images
Figure CN121004475A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of machine tool machining fixtures, and more specifically to a machining fixture for long-axis-distance parts. Background Technology
[0002] In the manufacturing of ride-on lawnmowers for field operations, components such as the YT145 housing and cover, and the MT37EG hydraulic gearbox housing and cover are key parts, and their machining quality has a significant impact on the overall performance of the lawnmower. These parts need to meet the requirements of high-load continuous operation, and have stringent requirements for machining dimensional accuracy; however, actual machining faces many challenges.
[0003] The axial distance between the near-end and far-end bearing holes of these parts is as high as 270mm, and the far-end bearing hole has a slender structure and is far from the main cavity, resulting in weak structural strength and poor rigidity in the far-end bearing hole area. During the machining process, the insufficient rigidity makes it prone to vibration, making it extremely difficult to ensure the accuracy indicators such as cylindricity and coaxiality, often resulting in out-of-tolerance problems, affecting the quality of the parts and their subsequent assembly and performance.
[0004] Existing machining fixtures are mostly designed for parts with conventional wheelbases and relatively simple structures, making them unsuitable for machining parts with long wheelbases and special structures at the far end. For example, some fixtures cannot provide effective and stable support and clamping for the far-end bearing hole, making it difficult to suppress vibration during machining; or the clamping scheme does not consider the coordination between near-end and far-end clamping under long wheelbases, resulting in unstable clamping, which can easily cause problems such as tool vibration and collision during machining, reducing machining efficiency and yield, and increasing production costs.
[0005] Therefore, there is an urgent need for a machining fixture suitable for parts with long wheelbases and special remote structures to solve problems such as poor clamping stability and difficulty in ensuring machining accuracy. Summary of the Invention
[0006] The present invention aims to provide a machining fixture for long-axis-spacing parts to solve the problem of excessive cylindricity and coaxiality when machining long-axis-spacing parts with existing fixtures.
[0007] To achieve the above objectives, the present invention adopts the following technical solution:
[0008] A long-axis part machining fixture includes a four-axis spindle and a tailstock. A main board is connected between the four-axis spindle and the tailstock. The front of the main board is provided with a clamping component, a support component, and a limiting component. The support component is used to support the part at the bottom, the clamping component is used to clamp the part above the support component, and the limiting component is used to limit the part at the edge. A clearance hole is opened in the middle of the main board to avoid the part. Two floating support cylinders are symmetrically arranged on the back of the main board. The floating support cylinders are used to clamp the distal end of the part. A hydraulic sequence valve is provided on the main board. The clamping component and the floating support cylinders are both connected to the hydraulic sequence valve. The hydraulic sequence valve is used to control the sequential action of the clamping component and the floating support cylinders. The proximal end of the part is positioned on the front of the main board, and the distal end of the part is positioned on the back of the main board through the clearance hole.
[0009] Preferably, as an improvement, the clamping assembly includes a first clamping cylinder, a second clamping cylinder, and a third clamping cylinder, which are arranged in a triangular pattern.
[0010] Preferably, as an improvement, the support assembly includes a level seat and a support base. The level seat is located at the first clamping cylinder to cooperate with the first clamping cylinder to clamp the parts, and the support base is located at the second clamping cylinder and the third clamping cylinder to cooperate with the second clamping cylinder and the third clamping cylinder to clamp the parts, respectively.
[0011] Preferably, as an improvement, a positioning pin is provided on the top of the support base, which is used to position the part by inserting it into the positioning hole of the part.
[0012] Preferably, as an improvement, the top of the support base is provided with a leveling block, and both the leveling block and the top of the leveling base are provided with airtight anti-misalignment holes. The airtight anti-misalignment holes are connected to an air supply component and a detection component. The detection component is electrically connected to a controller, and the controller is electrically connected to an alarm.
[0013] Preferably, as an improvement, the limiting component includes multiple contour-following limiting blocks.
[0014] Preferably, as an improvement, the four-axis is connected to a four-axis main board, the four-axis main board is connected to the main board, an oil distribution block is fixed on the four-axis main board, the oil distribution block is connected to an oil distributor, an oil passage is opened in the main board, the oil pressure sequence valve is connected to the oil distribution block through the oil passage, and the first pressing cylinder, the second pressing cylinder, the third pressing cylinder and the floating support cylinder are connected to the oil pressure sequence valve through the oil passage.
[0015] Preferably, as an improvement, a lifting ring is fixed on the back of the motherboard.
[0016] Preferably, as an improvement, the quantity is four, with the four lifting rings set at the four corners of the motherboard.
[0017] Preferably, as an improvement, the motherboard also has support feet at the four corners.
[0018] The beneficial effects of this plan are:
[0019] 1. The most stable mathematical and geometric model is used to construct an equidistant three-point support surface and two positioning pins for positioning. With the first, second and third clamping cylinders distributed in a triangle for clamping, not only is the clamping stability of the part guaranteed, but also the six degrees of freedom of the part are effectively restricted through multi-point collaborative positioning, which greatly improves the positioning accuracy and reduces displacement deformation during the processing. From the basic positioning level, it avoids the cylindricity and coaxiality deviation caused by unstable clamping.
[0020] 2. The design incorporates contour-following limit blocks that facilitate part clamping. The contours of these blocks match the edges of the parts, guiding them to be placed quickly and accurately. This not only improves the efficiency of part clamping but also prevents scratches caused by improper clamping during the first attempt. Furthermore, it avoids dimensional deviations in machining due to clamping offsets, indirectly ensuring cylindricity and coaxiality accuracy.
[0021] 3. For situations where the rigidity of the distal bearing hole is weak and prone to machining vibration: The floating support cylinder can automatically adapt to the part contour and lock in the appropriate position, effectively enhancing the rigidity of the distal support, reducing surface roughness problems caused by machining errors and vibrations, and avoiding machining deformation caused by insufficient distal rigidity. This solves the problem of excessive cylindricity and coaxiality when machining the distal end of long-axis parts. At the same time, the hydraulic sequence valve strictly controls the action sequence, ensuring that the clamping cylinder clamps the part first, and then the floating support cylinder performs the locking action. This avoids the situation where the clamping cylinder cannot effectively clamp the part due to the floating support cylinder acting prematurely, fundamentally eliminating the risk of tool collision during machining and ensuring the safety of equipment and parts.
[0022] 4. Airtight anti-misalignment holes are designed at the three-point support leveling points (top of the leveling block and leveling seat). A stable air source is provided through the air supply component. The detection component senses the gap between the product and the support surface in real time. If the gap exceeds the standard (i.e., the clamping is not in place), the controller can immediately trigger the alarm to remind the operator, realizing real-time monitoring of the clamping status. This effectively avoids processing defects caused by improper clamping and ensures that the parts are processed in the correct clamping state, providing a prerequisite for ensuring cylindricity and coaxiality accuracy.
[0023] 5. The structural design of the four-axis and tailstock connecting to the main board, combined with the integrated oil circuit layout of the oil distribution block and oil distributor on the four-axis main board and the built-in oil channels of the main board, reduces the messy interference of external pipelines, which not only improves the structural compactness of the fixture and the cleanliness of the equipment, but also facilitates oil circuit maintenance and improves the stability of equipment operation.
[0024] 6. The lifting rings at the four corners on the back of the mainboard facilitate the handling and installation of the clamp. Together with the support feet at the four corners, they ensure the stability of the clamp during storage and installation, and also make it convenient for operators to adjust the position and maintain it, thus improving the overall ease of operation.
[0025] In summary, this solution effectively solves the problem of excessive cylindricity and coaxiality when machining long-axis parts by means of multiple designs such as precise positioning, rigid support, sequential control and clamping detection. It breaks through the technical barrier that long-axis parts with long holes must rely on special machine tools (horizontal machining equipment or five-axis equipment) to meet the machining requirements with general-purpose CNC machine tools, while taking into account machining accuracy, operating efficiency, safety and economy. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention.
[0027] Figure 2 for Figure 1 An enlarged schematic diagram of part A in the middle.
[0028] Figure 3 This is a front view of an embodiment of the present invention.
[0029] Figure 4 This is a partial top view of the present invention.
[0030] Figure 5 This is a partial bottom view of the present invention.
[0031] The reference numerals in the accompanying drawings of the instruction manual include: 1. Four-axis, 2. Tailstock, 3. Main board, 4. Clearance hole, 5. Floating support cylinder, 6. Hydraulic sequence valve, 7. First clamping cylinder, 8. Second clamping cylinder, 9. Third clamping cylinder, 10. Elevation seat, 11. Support seat, 12. Positioning pin, 13. Elevation block, 14. Airtight anti-misalignment hole, 15. Contour limit block, 16. Four-axis main board, 17. Oil distribution block, 18. Lifting ring, 19. Support foot, 21. Part. Detailed Implementation
[0032] The present invention will be further described in detail below with reference to the embodiments.
[0033] Example
[0034] like Figure 1 , Figure 3 , Figure 4 and Figure 5 As shown, a long-axis part machining fixture includes a four-axis spindle 1 and a tailstock 2, with a main board 3 bolted between the four-axis spindle 1 and the tailstock 2. The front of the main board 3 has a clamping assembly, a support assembly, and a limiting assembly. The support assembly supports part 21 at the bottom, the clamping assembly clamps part 21 above the support assembly, and the limiting assembly limits part 21 at its edges. The limiting assembly includes multiple contour-following limiting blocks 15 bolted to the main board 3. Four lifting rings 18 are bolted to the back of the main board 3, located at the four corners of the main board 3. Support feet 19 are also bolted to the four corners of the main board 3.
[0035] The clamping assembly includes a first clamping cylinder 7, a second clamping cylinder 8, and a third clamping cylinder 9. The first clamping cylinder 7, the second clamping cylinder 8, and the third clamping cylinder are fixed on the main board 3 and are arranged in a triangular pattern. The first clamping cylinder 7, the second clamping cylinder 8, and the third clamping cylinder 9 are all lever-type hydraulic cylinders.
[0036] The support assembly includes a leveling seat 10 and a support base 11. The leveling seat 10 is bolted to the main plate 3 at the first clamping cylinder 7 to cooperate with the first clamping cylinder 7 in clamping the part 21. There are two support bases 11, which are bolted to the main plate 3 at the second clamping cylinder 8 and the third clamping cylinder 9 respectively, and cooperate with the second clamping cylinder 8 and the third clamping cylinder 9 to clamp the part 21 respectively. Figure 2 As shown, each of the two support bases 11 has a positioning pin 12 fixed on its top. The positioning pin 12 is used to be inserted into the positioning hole of the part 21 to position the part 21.
[0037] The tops of the two support bases 11 are also integrally formed with leveling blocks 13. Both leveling blocks 13 and leveling bases 10 have airtight anti-misalignment holes 14 on their tops. These holes 14 connect to an air supply assembly and a detection element. The detection element is a pressure sensor, electrically connected to a controller (a PLC), which is also electrically connected to an alarm (an audible and visual alarm). The air supply assembly includes an air compressor, an air tank, a pressure regulating valve, and a solenoid valve connected in sequence. Both the pressure regulating valve and the solenoid valve are electrically connected to the controller.
[0038] The main board 3 has a clearance hole 4 in the middle to avoid the part 21. Two floating support cylinders 5 are symmetrically bolted to the back of the main board 3. The floating support cylinders 5 are used to clamp the distal end of the part 21 and are hydraulically supported. A hydraulic sequence valve 6 is bolted to the front of the main board 3. A four-axis main board 16 is connected to the four-axis main board 16, which is connected to the main board 3. An oil distribution block 17 is fixed on the four-axis main board 16, and the oil distribution block 17 is connected to an oil distributor. An oil passage is provided inside the main board 3. The hydraulic sequence valve 6 is connected to the oil distribution block 17 through the oil passage. The first clamping cylinder 7, the second clamping cylinder 8, the third clamping cylinder 9, and the floating support cylinder 5 are connected to the hydraulic sequence valve 6 through the oil passage. The hydraulic sequence valve 6 is used to control the sequential action of the clamping assembly and the floating support cylinder 5.
[0039] In practical application, the operator aligns the proximal end of the long-axis component 21 with the front of the motherboard 3, allowing the distal end of component 21 to extend through the clearance hole 4 in the middle of the motherboard 3 to the back of the motherboard 3. During placement, the edge of component 21 contacts multiple contour-following limit blocks 15 of the limiting assembly. The contour of the contour-following limit blocks 15 matches the edge of component 21, guiding component 21 to be quickly positioned and avoiding misalignment or scratches on the appearance due to placement deviation.
[0040] After part 21 is placed in place, the support assembly begins to function. The level seat 10 at the first clamping cylinder 7 and the support seats 11 at the second clamping cylinder 8 and the third clamping cylinder 9 support part 21 from the bottom, forming a stable three-point support surface. The positioning pins 12 at the top of the two support seats 11 are inserted into the positioning holes of part 21 to further precisely position part 21 and restrict the movement and rotation of part 21.
[0041] The gas supply assembly is activated, and gas enters the gap between part 21 and the top of the leveling block 13 and leveling seat 10 through the airtight anti-misalignment hole 14. The detection component monitors the gas pressure change in real time. If part 21 is properly clamped and the gap meets the requirements, the gas pressure is stable; if it is not properly clamped and the gap is too large, the gas pressure drops, and the detection component transmits a signal to the controller. The controller triggers the alarm to issue a warning, reminding the operator to readjust the position of part 21 until the airtightness test is passed.
[0042] After the airtightness test is passed, the hydraulic system is started, and the hydraulic sequence valve 6 begins to work. First, it controls the action of the clamping components. The first clamping cylinder 7, the second clamping cylinder 8, and the third clamping cylinder 9, which are triangularly distributed, clamp the part 21 above the level seat 10 and the support seat 11, respectively, to ensure that the near end of the part 21 is stable. After the clamping cylinders complete their clamping action, the hydraulic sequence valve 6 controls the action of the two floating support cylinders 5 symmetrically arranged on the back of the main board 3. The floating support cylinders 5 automatically adapt to the contour of the far end of the part 21 and lock in the appropriate position, clamping the far end of the part 21 from the back, enhancing the support rigidity of the far end and avoiding vibration and errors during processing.
[0043] After clamping, the four-axis 1 drives the fixture and part 21 to perform machining operations according to the preset program. During the machining process, the integrated oil circuit layout reduces interference from external pipelines, ensures the stable operation of the hydraulic system, and ensures the continuous and reliable clamping and support.
[0044] After processing, the hydraulic sequence valve 6 controls each hydraulic component to reset sequentially, the floating support cylinder 5 releases its clamping of the distal end of part 21, and the clamping cylinder releases its clamping of the proximal end of part 21. The operator removes part 21 from the fixture, completing one processing cycle.
[0045] If the clamp needs to be moved, it can be moved using the lifting rings 18 at the four corners of the back of the main board 3. The support feet 19 provide stable support when the clamp is stored and installed, making it convenient for operators to adjust the position and perform daily maintenance.
[0046] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.
Claims
1. A machining fixture for long-axis-spacing parts, characterized in that: It includes a four-axis spindle and a tailstock, with a main board connected between the four-axis spindle and the tailstock. The front of the main board has a clamping assembly, a support assembly, and a limiting assembly. The support assembly supports the part at the bottom, the clamping assembly clamps the part above the support assembly, and the limiting assembly limits the part at the edge. The main board has a clearance hole in the middle to avoid the part. Two floating support cylinders are symmetrically arranged on the back of the main board. The floating support cylinders are used to clamp the far end of the part. The main board is equipped with a hydraulic sequence valve. The clamping assembly and the floating support cylinders are both connected to the hydraulic sequence valve. The hydraulic sequence valve is used to control the sequential action of the clamping assembly and the floating support cylinders. The near end of the part is positioned on the front of the main board, and the far end of the part is positioned on the back of the main board through the clearance hole.
2. The long-axis-spacing part machining fixture according to claim 1, characterized in that: The clamping assembly includes a first clamping cylinder, a second clamping cylinder, and a third clamping cylinder, which are arranged in a triangular pattern.
3. A long-axis-spacing part machining fixture according to claim 2, characterized in that: The support assembly includes a leveling seat and a support base. The leveling seat is located at the first clamping cylinder to cooperate with the first clamping cylinder to clamp the parts. The support base is located at the second and third clamping cylinders to cooperate with the second and third clamping cylinders to clamp the parts, respectively.
4. A long-axis-spacing part machining fixture according to claim 3, characterized in that: A positioning pin is provided on the top of the support base. The positioning pin is used to position the part by inserting it into the positioning hole of the part.
5. A long-axis-spacing part machining fixture according to claim 4, characterized in that: The top of the support base is equipped with a leveling block. Both the leveling block and the top of the leveling base are provided with airtight anti-misalignment holes. The airtight anti-misalignment holes are connected to an air supply component and a detection component. The detection component is electrically connected to a controller, and the controller is electrically connected to an alarm.
6. A long-axis-spacing part machining fixture according to claim 1, characterized in that: The limiting component includes multiple contour-following limiting blocks.
7. A long-axis-spacing part machining fixture according to claim 1, characterized in that: The four-axis is connected to a four-axis main board, and the four-axis main board is connected to the main board. An oil distribution block is fixed on the four-axis main board, and the oil distribution block is connected to an oil distributor. An oil passage is opened in the main board. The oil pressure sequence valve is connected to the oil distribution block through the oil passage. The first clamping cylinder, the second clamping cylinder, the third clamping cylinder and the floating support cylinder are connected to the oil pressure sequence valve through the oil passage.
8. A long-axis-spacing part machining fixture according to any one of claims 1-7, characterized in that: There is a hanging ring on the back of the motherboard.
9. A long-axis-spacing part machining fixture according to claim 8, characterized in that: There are four lifting rings, which are located at the four corners of the motherboard.
10. A long-axis-spacing part machining fixture according to claim 9, characterized in that: The motherboard also has support feet at its four corners.