A gear grinding machine for grinding spiral bevel gears

Abstract

The present application discloses a gear grinding machine for grinding spiral bevel gears, which includes a machine body. A positioning mechanism and a grinding mechanism are provided on the machine body. A two-axis drive turntable for placing gears is arranged on the positioning mechanism. The grinding mechanism includes a grinding wheel box connected to a lifting mechanism. A grinding wheel for processing gears and a coolant spraying device are installed on the grinding wheel box. The grinding wheel can rotate around the C axis. A measuring device that can move linearly along the Z axis under the drive of a hydraulic cylinder is provided on the right side of the grinding wheel box. Through the mutual cooperation of the positioning mechanism and the grinding mechanism, the device can be accurately positioned to grind gears.

Description

Technical Field

[0001] The present invention relates to numerical control machining equipment, and further refers to a gear grinding machine for grinding spiral bevel gears. Background Art

[0002] In the prior art, spiral bevel gear processing equipment includes mechanical spiral bevel gear grinding machines and numerical control spiral bevel gear grinding machines. The structure and adjustment links of mechanical spiral bevel gear grinding machines are the most complex among gear machines. With technological progress, spiral bevel gear grinding machines can simulate the machining movements of mechanical spiral bevel gear processing machines by directly controlling three linear axes (i.e., X, Y, and Z axes) and three rotating axes (i.e., A, B, and C axes) by a computer, so as to machine spiral bevel gears. The numerical control spiral bevel gear processing machine converts the complex mechanical structure into software control, realizing the digitization and intelligentization of spiral bevel gear processing. Spiral bevel gears can be machined by the generating method and the forming method. When the ratio of the number of teeth of the large gear to the number of teeth of the small gear is greater than 2.5, the tooth profile of the large gear is close to a straight line. At this time, the large gear can be machined by the forming method (referred to as a formed spiral bevel gear). The machining efficiency by the forming method is higher than that by the generating method. The small gear mating with the formed large gear is machined by the generating method (referred to as a generated spiral bevel gear). When the ratio of the number of teeth of the large gear to the number of teeth of the small gear is less than 2.5, both the large gear and the small gear are machined by the generating method. Existing gear grinding machines have the following disadvantages:

[0003] 1. When grinding spiral bevel gears by the forming method (grinding formed spiral bevel gears), the grinding wheel profile closely adheres to the tooth surfaces on both sides of the tooth groove of the spiral bevel gear, resulting in the coolant being unable to enter the grinding area, thereby causing a temperature rise, affecting the service life of the grinding wheel and the gear machining accuracy, and easily causing tooth surface burns and even cracks.

[0004] 2. In some existing numerical control spiral bevel gear grinding machines, to avoid the above problems, an eccentric sleeve is sleeved outside the grinding wheel spindle. Through the high-speed rotation of the eccentric sleeve and the self-rotation of the grinding wheel spindle, lifting grinding is realized to achieve the purpose of allowing the coolant to enter the grinding area. However, the entire spindle structure is complex, and there is a large vibration during operation, affecting the accuracy retention and stability of the spindle system.

[0005] Currently, few devices can realize the switching between the two grinding methods. Therefore, when machining gears, there are many limitations; and when grinding spiral bevel gears by the forming method, it is difficult for the coolant to enter the grinding area.

[0006] Application Content

[0007] The purpose of this application is to address the above problems by providing a gear grinding machine for spiral bevel gears. In response to the problems that occur in existing gear grinding machines for spiral bevel gears, the machine structure is innovated. When grinding spiral bevel gears by the form grinding method, the grinding wheel box and the grinding wheel can reciprocate rapidly along the Z-axis linear guide, simplifying the machine structure, allowing the coolant to enter the grinding area, reducing the temperature in the grinding area, and improving the machining accuracy and accuracy retention of the machine. At the same time, a limiter device is added, enabling the machine to grind spiral bevel gears by both the form grinding method and the generating method, enhancing the application range and versatility of the machine.

[0008] To achieve the above objectives, the technical solution adopted in this application is a gear grinding machine for spiral bevel gears, which includes a machine body. A positioning mechanism and a grinding mechanism are provided on the machine body. A two-axis drive turntable for placing the gear is arranged on the positioning mechanism. The grinding mechanism includes a grinding wheel box connected to a lifting mechanism. A grinding wheel for machining the gear and a coolant spraying device are installed on the grinding wheel box. The grinding wheel can rotate around the C-axis. A measuring device that can move in the linear direction of the Z-axis driven by a hydraulic cylinder is provided on the right side of the grinding wheel box. A limiter for changing the grinding method is provided on the lifting mechanism. Through the mutual cooperation of the positioning mechanism and the grinding mechanism, the device can accurately position and grind the gear.

[0009] Further, to facilitate gear positioning, the gear reaches the required position through a positioning device. The positioning mechanism includes a Y-axis slide table that moves along the Y-axis linear guide and an X-axis slide table that moves along the X-axis linear guide. An X-axis linear guide is provided on the Y-axis slide table, and a two-axis drive turntable is installed on the X-axis slide table.

[0010] Further, to effectively drive the two-axis drive turntable to rotate and facilitate grinding the grinding wheel, the two-axis drive turntable is connected to a turntable drive structure, and the two-axis drive turntable is connected to a grinding wheel dresser.

[0011] Further, to maintain the sharpness of the grinding wheel and enable it to be repaired after being damaged, the grinding wheel is ground and repaired by a grinding wheel dresser. A rotatable diamond roller is installed on the grinding wheel dresser.

[0012] Further, to enable the grinding wheel box to quickly and stably lift to the required position, the grinding wheel box is lifted by a lifting mechanism. The lifting mechanism includes a first Z-axis linear guide arranged on a fixed column, and a Z-axis slide table that moves along this guide is installed on the first Z-axis linear guide.

[0013] Further, to enable the grinding wheel box to perform slow lifting grinding on the gear, a lifting device for enabling the grinding wheel box to perform lifting grinding is provided on the upper Z-axis slide table.

[0014] Furthermore, in order to further improve the effect and controllability of lifting grinding, the lifting and grinding of the grinding wheel box is controlled by a lifting device; the lifting device includes an eccentric wheel mechanism and a stopper arranged on the Z-axis slide table, the Z-axis slide table is provided with a second Z-direction linear guide for the movement of the grinding wheel box, and the eccentric wheel mechanism drives the grinding wheel box to reciprocate up and down along the second Z-direction linear guide.

[0015] Advantages of this application: In the present invention, the motor drives the eccentric wheel mechanism to rotate, and the eccentric wheel drives the grinding wheel box to move rapidly back and forth along the Z-direction linear guide through a connecting block, replacing the structure of adding an eccentric sleeve to the grinding wheel spindle of the existing machine tool, simplifying the machine tool structure, reducing machining vibration, and improving machining efficiency; using the eccentric wheel mechanism to make the motor drive the grinding wheel box to achieve rapid reciprocating motion, the machine tool has better rigidity. Description of the Drawings

[0016] Figure 1 It is a schematic structural diagram of the machine tool of the present invention.

[0017] Figure 2 It is a schematic side view structural diagram of the machine tool.

[0018] Figure 3 It is a schematic diagram of the eccentric wheel mechanism.

[0019] The text markings in the figure are represented as: 1. Bed; 2. Y-axis slide table; 3. X-direction linear guide; 4. Grinding wheel dresser; 5. Diamond roller; 6. Grinding wheel box; 7. Second Z-direction linear guide; 8. Stopper; 9. Column; 10. First Z-direction linear guide; 11. Eccentric wheel mechanism; 12. Z-axis slide table; 13. Hydraulic cylinder; 14. Grinding wheel; 15. Measuring device; 16. Coolant injection device; 17. Gear; 18. Biaxial turntable; 19. Turntable drive mechanism; 20. X-axis slide table; 21. Y-direction linear guide; 22. Bearing. Detailed Embodiments

[0020] In order to enable those skilled in the art to better understand the technical solutions of this application, the following describes this application in detail with reference to the drawings. The description in this part is only exemplary and explanatory, and should not have any restrictive effect on the protection scope of this application.

[0021] Embodiment 1:

[0022] Combined with Figure 1 、 Figure 2; A gear grinding machine for grinding spiral bevel gears, which comprises a machine body 1. A positioning mechanism and a grinding mechanism are provided on the machine body 1. A two-axis drive turntable 18 for placing a gear 17 is arranged on the positioning mechanism. The grinding mechanism includes a grinding wheel box 6 connected to a lifting mechanism. A grinding wheel 14 for machining gears and a coolant spraying device 16 are installed on the grinding wheel box 6. The grinding wheel 14 can rotate around the C axis. A measuring device 15 that can move in a straight line along the Z axis driven by a hydraulic cylinder 13 is arranged on the right side of the grinding wheel box 6. A stopper 8 for changing the grinding mode is arranged on the lifting mechanism. In this embodiment, the measuring device is a probe for in-machine contact measurement of a numerical control machine tool. Automatic tool setting, measurement of gear pitch deviation and tooth profile error can be realized by the contact between the probe and the gear.

[0023] Embodiment 2:

[0024] Combined with Figure 1 、 Figure 2; A gear grinding machine for grinding spiral bevel gears, which includes a machine body 1. A positioning mechanism and a grinding mechanism are provided on the machine body 1. A dual-axis drive turntable 18 for placing a gear 17 is arranged on the positioning mechanism. The grinding mechanism includes a grinding wheel box 6 connected to a lifting mechanism. A grinding wheel 14 for machining gears and a coolant spraying device 16 are installed on the grinding wheel box 6. The grinding wheel 14 can rotate around the C axis. A measuring device 15 that can move in the linear direction of the Z axis driven by a hydraulic cylinder 13 is provided on the right side of the grinding wheel box 6. A limiter 8 for changing the grinding method is provided on the lifting mechanism. The positioning mechanism includes a Y-axis slide 2 that moves along a Y-direction linear guide 21 and an X-axis slide 20 that moves along an X-direction linear guide 3. An X-direction linear guide 3 is provided on the Y-axis slide 2. A dual-axis drive turntable 18 is installed on the X-axis slide 20. The dual-axis drive turntable 18 is connected to a turntable drive structure 19 and is connected to a grinding wheel dresser 4. A rotatable diamond roller 5 is installed on the grinding wheel dresser 4. In this embodiment, the dual-axis drive turntable 18 can rotate around the B axis by itself. A workpiece spindle and a gear fixture for placing the gear 17 are provided on the dual-axis drive turntable 18. A workpiece spindle that can rotate around the A axis is provided on the dual-axis drive turntable 18. In this embodiment, the Y-axis slide 2 and the X-axis slide 20 move driven by a drive mechanism. The drive mechanism is composed of a lead screw mechanism driven by a drive motor, so as to make the slide move along the guide rail. The dual-axis drive turntable 18 can rotate around the B axis driven by the turntable drive structure 19. The turntable drive structure 19 includes support columns arranged on both sides of the dual-axis drive turntable 18. A drive motor for driving the dual-axis drive turntable 18 is arranged inside the support columns. The angle between the axis of the gear 17 and the axis of the grinding wheel 14 is adjusted through the dual-axis drive turntable 18. The diamond roller 5 is used to dress the grinding wheel 14 to ensure that the grinding wheel 14 can achieve the required cutting profile shape and machining effect. In this embodiment, the diamond roller 5 rotates around the D axis, and the eccentric wheel mechanism 11 rotates around the E axis.

[0025] Embodiment Three:

[0026] Combined with Figure 1 、 Figure 2 、 Figure 3; A gear grinding machine for grinding spiral bevel gears, which comprises a machine body 1. A positioning mechanism and a grinding mechanism are provided on the machine body 1. A dual-axis drive turntable 18 for placing a gear 17 is arranged on the positioning mechanism. The grinding mechanism includes a grinding wheel box 6 connected to a lifting mechanism. A grinding wheel 14 for machining gears and a coolant spraying device 16 are installed on the grinding wheel box 6. The grinding wheel 14 can rotate around the C axis. A measuring device 15 that can move in the linear direction of the Z axis driven by a hydraulic cylinder 13 is provided on the right side of the grinding wheel box 6. A stopper 8 for changing the grinding method is provided on the lifting mechanism. The lifting mechanism includes a first Z-direction linear guide rail 10 provided on a fixed column 9. A Z-axis slide 12 that moves along this guide rail is installed on the first Z-direction linear guide rail 10. A lifting device for lifting and grinding the grinding wheel box 6 is provided on the Z-axis slide 12. The lifting device includes an eccentric wheel mechanism 11 and a stopper 8 provided on the Z-axis slide 12. A second Z-direction linear guide rail 7 for the grinding wheel box 6 to move is provided on the Z-axis slide 12. The eccentric wheel mechanism 11 drives the grinding wheel box 6 to perform reciprocating lifting along the second Z-direction linear guide rail 7. In this embodiment, the Z-axis slide 12 is driven by a moving device, and the moving device is a lead screw mechanism driven by a driving motor. In this embodiment, different gear processing methods are realized by adjusting the eccentric wheel mechanism 11 and the stopper 8. When grinding a spiral bevel gear by the forming method, the eccentric wheel mechanism 11 is first located at the initial position. When the lead screw drives the grinding wheel 14 to move along the first Z-direction linear guide rail 10, the program controls the motor to drive the eccentric wheel mechanism 11 to rotate, so that the grinding wheel box performs reciprocating motion along the second Z-direction linear guide rail 7, realizing intermittent lifting and grinding. The motion range is 2emm, where e is the eccentricity of the eccentric wheel. Generally, e is 0.01 - 0.025mm, and the size of e can be determined according to the specifications of the gears machined by the machine tool. When grinding a spiral bevel gear by the generating method, the eccentric wheel mechanism 11 is locked by the stopper 8, and the grinding wheel box 14 stops at the specified position. Under program control, the five axes of X, Y, Z, A, and B are linked to make the grinding wheel and the gear perform a meshing generating motion to grind the tooth surface of the spiral bevel gear processed by the generating method.

[0027] During actual operation: Place the gear to be processed on the dual-axis drive turntable 18. When grinding spiral bevel gears by the generating method, the relative positions of the grinding wheel 14 and the gear 17 are completely determined by three linear axes (X, Y, Z axes) and two rotational axes (A, B axes). When grinding each tooth space, the X, Y, A, and B axes remain stationary, while the first Z axis moves slowly. In addition, the second Z axis reciprocates rapidly during operation. While driving the grinding wheel box 6 and the grinding wheel 14 for gear processing to feed along the first Z-direction linear guide 10 through the lead screw, the eccentric wheel mechanism 11 operates, causing the grinding wheel box 6 and the grinding wheel 14 to perform rapid reciprocating motion along the second Z-direction linear guide 7, achieving intermittent up-and-down grinding. When the grinding wheel box 6 and the grinding wheel 14 perform rapid reciprocating motion, when the grinding wheel profile disengages from the gear tooth surface, the coolant can enter the grinding area to cool the grinding area. When grinding spiral bevel gears by the generating method, the stopper 8 operates to hold against the grinding wheel box 6, and the eccentric wheel 11 locks and does not operate. By the five-axis linkage of X, Y, Z, A, and B (when using the tool tilt function to modify the tooth surface) or the four-axis linkage of X, Y, Z, and A (when not using the tool tilt function), spiral bevel gears can be ground by the generating method. When grinding spiral bevel gears by the generating method, the grinding wheel profile has a line contact with the tooth surfaces on both sides of the tooth space, and there is no problem that the coolant cannot enter the grinding area. Therefore, the eccentric wheel mechanism 11 does not operate.

[0028] It should be noted that in this text, the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device including a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0029] In this article, specific examples are used to elaborate on the principles and implementation manners of the present application. The descriptions of the above examples are only used to help understand the method and its core idea of the present application. The above are only the preferred implementation manners of the present application. It should be noted that due to the limitation of literal expression, objectively there are infinite specific structures. For those of ordinary skill in the art in this technical field, without departing from the principle of the present application, several improvements, refinements or changes can be made, or the above technical features can be combined in an appropriate manner; these improvements, refinements, changes or combinations, or directly applying the concept and technical solution of the application to other occasions without improvement, shall all be regarded as the protection scope of the present application.

Claims

1. A gear grinding machine for grinding spiral bevel gears, which comprises a machine body (1), a positioning mechanism and a grinding mechanism are arranged on the machine body (1), and a dual-axis drive turntable (18) for placing a gear (17) is arranged on the positioning mechanism; characterized in that: The grinding mechanism includes a grinding wheel box (6) connected to the lifting mechanism. A grinding wheel (14) for machining gears and a coolant spraying device (16) are installed on the grinding wheel box (6). The grinding wheel (14) can rotate around the C axis. A measuring device (15) is provided on the right side of the grinding wheel box (6), which can move in the linear direction of the Z axis driven by a hydraulic cylinder (13). A stopper (8) for changing the grinding mode is provided on the lifting mechanism. The lifting mechanism includes a first Z-direction linear guide rail (10) provided on a fixed column (9). A Z-axis slide (12) that moves along this guide rail is installed on the first Z-direction linear guide rail (10). A lifting device for causing the grinding wheel box (6) to perform lifting grinding is provided on the Z-axis slide (12). The lifting device includes an eccentric wheel mechanism (11) provided on the Z-axis slide (12). The stopper (8) is provided on the Z-axis slide (12). The Z-axis slide (12) is provided with a second Z-direction linear guide rail (7) for the movement of the grinding wheel box (6). The eccentric wheel mechanism (11) drives the grinding wheel box (6) to perform reciprocating lifting along the second Z-direction linear guide rail (7).

2. The gear grinding machine for grinding spiral bevel gears according to claim 1, characterized in that: The positioning mechanism includes a Y-axis slide (2) that moves along a Y-direction linear guide rail (21) and an X-axis slide (20) that moves along an X-direction linear guide rail (3). An X-direction linear guide rail (3) is provided on the Y-axis slide (2). A dual-axis drive turntable (18) is installed on the X-axis slide (20).

3. The gear grinding machine for grinding spiral bevel gears according to claim 2, characterized in that: The dual-axis drive turntable (18) is connected to a turntable drive structure (19), and the turntable drive structure (19) is connected to a grinding wheel dresser (4).

4. The gear grinding machine for grinding spiral bevel gears according to claim 3, characterized in that: A rotatable diamond roller (5) is installed on the grinding wheel dresser (4).

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