Combined machining machine tool for grinding external threads and hobbing of shaft parts

Abstract

The utility model provides a combined processing machine tool for external thread grinding and gear hobbing of shaft parts, which comprises a machine tool body, an external thread grinding mechanism, a gear hobbing mechanism, a driver, a sliding frame and a pair of head and tail frames, each head and tail frame is provided with a servo motor and a clamping device, and the clamping devices are driven by the servo motors to rotate. The pair of head and tail frames are oppositely arranged, the two ends of the shaft part are clamped and fixed through the clamping devices correspondingly, the positions, away from each other and close to each other, of the pair of head and tail frames in the axial direction of the shaft part are adjustable, and at least one head and tail frame is provided with a driver. The driver can drive the pair of head and tail frames to move in the directions away from each other and close to each other in the axial direction of the shaft part. According to the utility model, the shaft part is subjected to external thread grinding and gear hobbing in the state of being axially stretched, so that central holes do not need to be pre-processed at the two ends of the shaft part, meanwhile, the shaft part is prevented from being unstable and deformed, and the combined processing precision is ensured.

Description

A composite machining tool for grinding external threads and hobbing gears on shaft parts. Technical Field

[0001] This utility model relates to the field of metal processing machine tool technology, and in particular to a composite machining tool for grinding external threads and hobbing gears on shaft parts. Background Technology

[0002] As industrial parts become increasingly complex, shafts are often designed with high-precision external threads, gear teeth, and other intricate structures. To improve the consistency of precision in these complex mechanisms, existing technologies employ center structures on the headstock and tailstock to form center holes at both ends of the shaft. By using the center structures to engage with these center holes, the external threads, gear teeth, and other additional structures are machined in a single operation while the shaft is axially clamped from both ends. However, pre-machining the center holes complicates the process, and errors in the center hole machining can affect the machining accuracy of the complex structures on the shaft. For small-diameter shafts, machining the center holes is extremely difficult, and for shafts with a large length-to-diameter ratio, the axial clamping method can easily cause instability and deformation, significantly reducing the yield rate. Summary of the Invention

[0003] This invention provides a composite machining tool for grinding external threads and hobbing gears on shaft parts.

[0004] Specifically, this utility model is achieved through the following technical solution:

[0005] This utility model embodiment provides a composite machining tool for grinding external threads and hobbing gears on shaft parts, including a bed, an external thread grinding mechanism, a gear hobbing mechanism, a driver, a carriage, and a pair of head and tailstocks. The external thread grinding mechanism, the gear hobbing mechanism, the carriage, and the pair of head and tailstocks are all mounted on the bed. Each head and tailstock is equipped with a servo motor and a clamping device. The clamping device is driven to rotate by the servo motor. The pair of head and tailstocks are arranged opposite to each other and clamp and fix the two ends of the shaft part respectively by the clamping device. At least one head and tailstock is movably mounted on the bed along the axial direction of the shaft part via the carriage, so that the position of the pair of head and tailstocks in the axial direction of the shaft part can be adjusted to move away from or closer to each other. At least one head and tailstock is equipped with a driver, so that the driver can drive the pair of head and tailstocks to move away from or closer to each other in the axial direction of the shaft part.

[0006] In some embodiments, an additional machining mechanism is also included, which is disposed on the bed to perform additional machining on shaft-type parts.

[0007] In some embodiments, the additional machining mechanism is selected from at least one of external cylindrical grinding, cutting mechanism, slicing mechanism, polishing mechanism, deburring mechanism, and knurling mechanism.

[0008] In some embodiments, a tool holder is also included, with the external thread grinding mechanism and the gear hobbing mechanism respectively disposed on different sides of the tool holder. The tool holder is rotatably mounted on the bed, thereby selectively positioning the external thread grinding mechanism and the gear hobbing mechanism facing the shaft-like parts.

[0009] In some embodiments, the external thread grinding mechanism may be rotated relative to the tool holder, thereby adjusting the external thread grinding angle between the grinding wheel of the external thread mechanism and the shaft part; and / or, the gear hobbing mechanism may be rotated relative to the tool holder, thereby adjusting the angle between the hobbing cutter axis of the gear hobbing mechanism and the axis of the shaft part.

[0010] In some embodiments, the actuator includes a piston, the piston cylinder and piston rod of which are respectively connected to a carriage and a head and tail carriage, thereby driving a pair of head and tail carriages to move in the axial direction toward each other and toward each other by piston movement.

[0011] In some embodiments, the drive further includes an elastic element connected between the carriage and the head and tail carriages, such that the elastic element can accumulate elastic restoring force as the pair of head and tail carriages move toward each other in the axial direction, and can release elastic restoring force as the pair of head and tail carriages move away from each other in the axial direction.

[0012] In some embodiments, a guide mechanism is provided between the carriage and the head and tail frames, which can guide the relative movement between the carriage and the head and tail frames in the axial direction.

[0013] In some embodiments, the guiding mechanism includes a slider and a guide rail, the carriage is provided with a side plate, and the slider and guide rail are disposed between the side plate and the head and tail frames and are respectively connected to the side plate and the head and tail frames.

[0014] In some embodiments, a buffer structure is provided on the side plate to form a buffer between the head and tail frames and the carriage at the limit position of relative movement in the axial direction.

[0015] According to the embodiments of this utility model, a pair of head and tailstock clamps are used to clamp the two ends of the shaft part. The driver drives the pair of head and tailstock clamps to put the shaft part in an axially stretched state. The external thread grinding mechanism and the gear hobbing mechanism perform external thread grinding and gear hobbing on the shaft part respectively. There is no need to pre-machine the center holes at both ends of the shaft part, and the shaft part is prevented from becoming unstable and deformed. The complex structure of the shaft part with a large length-to-diameter ratio can be completed in one clamping, ensuring the accuracy of the complex machining.

[0016] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0018] Figure 1 is a schematic diagram of a composite machining tool according to an embodiment of the present invention;

[0019] Figure 2 is a magnified view of part A in Figure 1;

[0020] Figure 3 is a front view of a composite machining tool according to an embodiment of the present invention;

[0021] Figure 4 is a top view of a composite machining tool according to an embodiment of the present invention.

[0022] Figure 5 is a schematic diagram of the head and tail frame in one embodiment of the present invention.

[0023] Figure label:

[0024] 10: Bed; 20: Headstock and tailstock; 21: Clamp; 22: Servo motor; 30: External thread grinding mechanism; 40: Driver; 51: Base; 52: Side plate; 61: Slider; 62: Guide rail; 63: Connecting plate; 64: Buffer block; 70: Gear hobbing mechanism; 80: Tool holder. Detailed Implementation

[0025] The present invention will now be discussed with reference to several embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present invention, and are not intended to imply any limitation on the scope of the present invention.

[0026] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to"; the terms "embodiment" and "one embodiment" are to be interpreted as "at least one embodiment"; the term "another embodiment" is to be interpreted as "at least one other embodiment"; the terms "first," "second," etc., may refer to different or the same objects; the term "setup" is not limited to direct or indirect connections, nor to specific connection methods. Other explicit and implicit definitions may also be included below.

[0027] Specific numerical values ​​or ranges may be mentioned in the following description. It should be understood that these values ​​and ranges are merely exemplary and may be helpful in putting the ideas of this invention into practice. However, the description of these examples is not intended to limit the scope of this invention in any way. These values ​​or ranges may be set differently depending on the specific application scenario and requirements.

[0028] As mentioned above, existing composite machining methods complicate the process by pre-machining center holes at the ends of shaft parts. Errors in center hole machining also affect the accuracy of composite machining. For small-diameter shaft parts, machining center holes is difficult, and for shaft parts with a large length-to-diameter ratio, axial clamping can easily cause instability and deformation, reducing the yield rate. The composite machining machine tool for grinding external threads and hobbing gears on shaft parts proposed in the embodiments of this utility model at least partially solves the above problems. The structure and working principle of the horizontal exemplary embodiment of the composite machining machine tool for grinding external threads and hobbing gears on shaft parts according to this utility model will be described below with reference to Figures 1 to 5. The structure and working principle of the embodiments of this utility model are also applicable to the working mode of vertical composite machining machine tools. As shown in Figures 1-5, the composite machining tool of this utility model generally includes a bed 10, an external thread grinding mechanism 30, a gear hobbing mechanism 70, a driver 40, a carriage, and a pair of head and tailstocks 20. In addition, it may include other components of conventional metalworking machine tools, such as a hydraulic system, a cooling system, a tool changing mechanism (e.g., a grinding wheel changing mechanism), and a tool dressing mechanism (e.g., a grinding wheel dressing mechanism). The grinding wheel of the external thread grinding mechanism 30 is used to grind external threads along the axial direction of shaft-like parts. The gear hobbing mechanism 70 is used to machine gear teeth on shaft-like parts. The carriage is used to movably connect the head and tailstocks to the bed. The driver 40 is used to drive the pair of head and tailstocks 20 to move in a direction away from each other. The bed 10 is used to support the grinding machine components. The external thread grinding mechanism 30 and the pair of head and tailstocks 20 are both mounted on the bed 10.

[0029] Each pair of head and tailstocks 20 is equipped with a servo motor 22 and a clamp 21. The clamp 21 is used to clamp and fix the end of the shaft part, and the servo motor 22 is used to drive the clamp 21 to rotate. By controlling the servo motors 22 of the pair of head and tailstocks 20 to rotate synchronously, the shaft part can be accurately driven to rotate around its own axis.

[0030] A pair of headstocks 20 are arranged aligned with each other on the bed 10. In one embodiment, the pair of headstocks 20 are each connected to the bed 10 via a carriage and a guide rail, so that each headstock 20 can move relative to the bed 10 along the guide rail, wherein the extension direction of the guide rail is aligned with the axial direction of the shaft component. In another embodiment, only one headstock 20 is connected to the bed 10 via a carriage and a guide rail, while the other headstock 20 is fixedly connected to the bed 10. In this case, adjusting the position of one headstock 20 can also achieve the purpose of adjusting the distance between the pair of headstocks 20. Exemplarily, the headstocks 20 are connected to the bed 10 via a carriage.

[0031] In one embodiment, an actuator 40 is provided on one headstock 20, and the actuator 40 is connected between the headstock 20 and the carriage. When the carriage is stationary, the actuator 40 is used to move the pair of headstocks 20 away from and towards each other, thereby achieving axial tension of the shaft-like parts. In another embodiment, actuators 40 are provided on each of the pair of headstocks 20, and the movement of the pair of headstocks 20 away from and towards each other can be achieved by using either one actuator 40 or by using both actuators 40 simultaneously.

[0032] In one embodiment, the actuator 40 is configured as a piston, with its piston cylinder and piston rod connected to the carriage and head / tail frame 20, respectively. Exemplarily, as shown in FIG. 5, the piston cylinder is fixed to the base 51 of the carriage, and the end of the piston rod is fixedly connected to the head / tail frame 20 (not shown in the figure), thereby driving the pair of head / tail frames 20 to move in the axial direction toward each other and toward each other through piston movement. In another example, the piston cylinder may also be fixed to the head / tail frame 20, with the end of the piston rod fixedly connected to the base 51 of the carriage.

[0033] In another embodiment, the actuator 40 consists of a piston and an elastic element connected between the carriage and the head and tail carriages 20. The piston drives the head and tail carriages 20 to move closer to each other. During this process, the elastic element accumulates elastic restoring force. When the two ends of the shaft part are clamped, the piston driving force is turned off, and the elastic restoring force of the elastic element is released, causing the pair of head and tail carriages 20 to move away from each other, thereby realizing the axial stretching action of the shaft part.

[0034] In one embodiment, a guide mechanism is provided between the carriage and the head and tail supports 20. The guide mechanism can guide the relative movement between the carriage and the head and tail supports 20 in the axial direction, thereby improving the accuracy of the stretching direction of the shaft parts and ensuring the machining accuracy of the external threads.

[0035] In one embodiment, the guiding mechanism includes a slider 61 and a guide rail 62. The carriage is provided with a base 51 and a sidewall. The slider 61 and the guide rail 62 are disposed between the sidewall and the head and tail frames 20 and are respectively connected to the sidewall and the head and tail frames 20. For example, as shown in FIG4, a plurality of sliders 61 are disposed on the side of the head and tail frames 20, and the guide rail 62 is disposed on the side plate 52, precisely guiding the relative movement between the carriage and the head and tail frames 20.

[0036] In one embodiment, a buffer structure is provided on the side plate 52 to buffer the head and tail frame 20 at the limit position of relative movement in the axial direction. Exemplarily, the buffer mechanism includes a connecting plate 63 and a buffer block 64. The connecting plate 63 is disposed on the side plate 52 and extends towards the head and tail frame 20, and the buffer block 64 is disposed at the extended end of the connecting plate 63, thereby preventing vibration or even deformation of shaft components due to rigid collision between the head and tail frame 20 and the carriage.

[0037] In one embodiment, the drive 40 and the guide mechanism are located on the same side of the head and tail frame 20 to ensure that the load force generated by the drive 40 and the guide mechanism when they are in operation is balanced relative to the head and tail frame 20, thus preventing the head and tail frame 20 from twisting.

[0038] The machine bed of this utility model embodiment is provided with at least an external thread grinding mechanism and a gear hobbing mechanism 70 for machining external threads and gear teeth on the outer periphery of shaft parts. For example, gear tooth structures are designed at both ends of the shaft part, and an external thread structure is designed in the area between the two ends. Those skilled in the art will understand that the positions of the external threads and gear teeth can be arbitrary, and machining can be achieved using the composite machining tool of this utility model embodiment.

[0039] In one embodiment, the external thread grinding mechanism and the gear hobbing mechanism 70 can be directly fixedly installed or movably installed on the machine bed. For example, one external thread grinding mechanism and a pair of gear hobbing mechanisms 70 can be provided. The external thread grinding mechanism and the pair of gear hobbing mechanisms 70 are arranged along the axial direction of the shaft part on one or both sides of the shaft part. For ease of processing, the external thread grinding mechanism is arranged between the pair of gear hobbing mechanisms 70. With this arrangement, the external thread grinding mechanism grinds the external thread close to the shaft part, and the gear hobbing mechanism 70 processes the gear tooth structure close to the shaft part.

[0040] In one embodiment, the external thread grinding mechanism and the gear hobbing mechanism 70 can be indirectly mounted on the machine bed via a tool holder 80. The tool holder 80 has at least two sides, on which the external thread grinding mechanism and the gear hobbing mechanism 70 are respectively disposed. The tool holder 80 is rotatable relative to the machine bed about a vertical axis a, so that the sides on which the external thread grinding mechanism and the gear hobbing mechanism 70 are mounted face the shaft-like parts. Exemplarily, only one external thread grinding mechanism and one gear hobbing mechanism 70 are respectively mounted on two sides of the tool holder 80. In another example, two or more external thread grinding mechanisms for grinding external threads of different specifications or two or more gear hobbing mechanisms 70 for machining gear tooth structures of different specifications can be respectively disposed on multiple different sides of the tool holder 80.

[0041] In one embodiment, the external thread grinding mechanism is rotatably mounted on the side of the tool holder 80, allowing it to rotate relative to the tool holder 80 around the first horizontal axis b1, thereby adjusting the external thread grinding angle between the grinding wheel and the shaft-like part. In another embodiment, the gear hobbing mechanism 70 is rotatably mounted on the side of the tool holder 80, allowing it to rotate relative to the tool holder 80 around the second horizontal axis b2, thereby adjusting the angle between the hobbing cutter axis and the shaft-like part axis. The gear hobbing employs a generating method, utilizing the meshing principle of the hobbing cutter and gears for machining.

[0042] When using the composite machining tool of this utility model, the moving carriage adjusts the distance between the pair of head and tailstocks to a suitable level. The driver then drives the pair of head and tailstocks to move away from each other in the axial direction of the shaft part with a large length-to-diameter ratio, thereby providing clearance space for the shaft part. When the shaft part is placed in the predetermined position, the driver can drive the pair of head and tailstocks to move closer to each other until they reach the clamping position. After the shaft part is clamped and fixed by the clamping device, the driver again drives the pair of head and tailstocks to move away from each other, thereby completing the axial stretching of the shaft part. In this state, for example, a shaft-type part with a gear tooth structure at both ends and an external thread structure in the middle is processed. The tool holder 80 rotates so that the external thread grinding mechanism faces the shaft-type part. Two servo motors rotate synchronously to drive the shaft-type part to rotate. At the same time, the grinding wheel of the external thread grinding mechanism rotates to traverse and grind the external thread. After the external thread is ground, the tool holder 80 rotates so that the gear hobbing mechanism 70 faces the shaft-type part. Two servo motors rotate synchronously to drive the shaft-type part to rotate. At the same time, the gear hobbing cutter of the gear hobbing mechanism 70 rotates to process the gear tooth structure at both ends of the shaft-type part in sequence. Thus, different processing steps can be completed with only one clamping of the shaft-type part, avoiding clamping errors caused by multiple clamping and ensuring the consistency of processing accuracy between different processing steps.

[0043] This utility model embodiment utilizes two servo motors rotating synchronously to achieve dual-drive rotation of shaft parts. When the cutting load applied to the shaft parts by the grinding wheel and hobbing cutter is located in either end region of the shaft parts, the servo motors can provide the shaft parts with sufficient and equal torsional resistance. In contrast, in the case of single-end drive of shaft parts in the prior art, the torsional resistance of the shaft parts at the free end is insufficient.

[0044] The tool carrier 80 of this embodiment can be indirectly mounted on the machine bed via a slide table, meaning the tool carrier 80 rotates relative to the slide table, and the slide table can drive the tool carrier 80 to move longitudinally relative to the machine bed. The slide for mounting the headstock and tailstock can also be indirectly mounted on the machine bed via the slide table, meaning that when a pair of headstocks and tailstocks are clamped onto the shaft-like parts, the slide table can drive the clamped shaft-like parts to move laterally relative to the machine bed. Through the above configuration, the external thread grinding mechanism and the gear hobbing mechanism 70 can be fed longitudinally and laterally relative to the shaft-like parts during the machining process. Those skilled in the art will understand that conventional feed structures can be used to achieve the feed movement during the external thread grinding and gear hobbing processes of shaft-like parts.

[0045] In one embodiment, in addition to the external thread grinding mechanism and the gear hobbing mechanism 70, the composite machining machine tool can also be equipped with an additional machining mechanism. The additional machining mechanism can be directly fixedly installed on the machine bed, or it can be installed on the side of the tool carriage 80 that is different from the side where the external thread grinding mechanism and the gear hobbing mechanism 70 are located. The tool carriage 80 rotates so that the external thread grinding mechanism, the gear hobbing mechanism 70 and the additional machining mechanism face the shaft parts respectively.

[0046] In one embodiment, the additional machining mechanism can be a conventional machining tool such as an external cylindrical grinding mechanism, a cutting mechanism, a polishing mechanism, a deburring mechanism, or a knurling mechanism, thereby increasing the machining steps of the composite machining center. For example, the additional machining mechanism can be a cutting mechanism. After external thread grinding and gear hobbing are completed, the cutting mechanism is used to cut the shaft-like part between the clamped portion and the end region gear tooth structure to obtain the finished product. In another example, the additional machining mechanism can be both a cutting mechanism and a deburring mechanism. In this case, the composite machining center can sequentially perform external cylindrical grinding, external thread grinding, gear hobbing, deburring, and cutting processes in a single clamping of the shaft-like part.

[0047] The description of the embodiments herein, including any references to directions and orientations, is for ease of description only and should not be construed as limiting the scope of protection of this utility model. The description of preferred embodiments involves combinations of features, which may exist independently or in combination; this utility model is not particularly limited to the preferred embodiments. The scope of this utility model is defined by the claims.

[0048] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A composite machining tool for grinding external threads and hobbing gears on shaft parts, characterized in that, The device includes a bed, an external thread grinding mechanism, a gear hobbing mechanism, a driver, a carriage, and a pair of head and tailstocks. The external thread grinding mechanism, gear hobbing mechanism, carriage, and pair of head and tailstocks are all mounted on the bed. Each head and tailstock is equipped with a servo motor and a clamping device. The clamping device is driven to rotate by the servo motor. The pair of head and tailstocks are arranged opposite to each other and clamp the two ends of the shaft-like part respectively by the clamping device. At least one head and tailstock is movably mounted on the bed along the axial direction of the shaft-like part via the carriage, so that the position of the pair of head and tailstocks in the axial direction of the shaft-like part can be adjusted to move away from or closer to each other. At least one head and tailstock is equipped with a driver, so that the driver can drive the pair of head and tailstocks to move away from or closer to each other in the axial direction of the shaft-like part.

2. The composite machining tool according to claim 1, characterized in that, It also includes an additional machining mechanism, which is set on the bed to perform additional machining on shaft parts.

3. The composite machining tool according to claim 2, characterized in that, The additional machining mechanism is selected from at least one of the following: external cylindrical grinding, cutting mechanism, cutting mechanism, polishing mechanism, deburring mechanism, and knurling mechanism.

4. The composite machining tool according to claim 1, characterized in that, It also includes a tool holder, with the external thread grinding mechanism and gear hobbing mechanism respectively located on different sides of the tool holder. The tool holder is rotatably mounted on the bed, so that the external thread grinding mechanism and gear hobbing mechanism can be selectively positioned to face shaft-type parts.

5. The composite machining tool according to claim 4, characterized in that, The external thread grinding mechanism can rotate relative to the tool holder, thereby adjusting the external thread grinding angle between the grinding wheel of the external thread mechanism and the shaft part; and / or, the gear hobbing mechanism can rotate relative to the tool holder, thereby adjusting the angle between the hobbing cutter axis of the gear hobbing mechanism and the axis of the shaft part.

6. The composite machining tool according to claim 1, characterized in that, The actuator includes a piston, the piston cylinder and piston rod of which are respectively connected to a carriage and a head and tail carriage, thereby driving a pair of head and tail carriages to move in the axial direction toward each other and toward each other through piston movement.

7. The composite machining tool according to claim 1, characterized in that, The drive also includes an elastic element connected between the carriage and the head and tail carriages, which allows the elastic element to accumulate elastic restoring force as the pair of head and tail carriages move toward each other in the axial direction, and to release elastic restoring force as the pair of head and tail carriages move away from each other in the axial direction.

8. The composite machining tool according to claim 1, characterized in that, A guide mechanism is provided between the carriage and the head and tail frames, which can guide the relative movement between the carriage and the head and tail frames in the axial direction.

9. The composite machining tool according to claim 8, characterized in that, The guiding mechanism includes a slider and a guide rail. The carriage is equipped with a side plate. The slider and guide rail are located between the side plate and the head and tail frames and are respectively connected to the side plate and the head and tail frames.

10. The composite machining tool according to claim 9, characterized in that, A buffer structure is provided on the side plate to form a buffer between the head and tail frames and the carriage at the limit position of relative movement in the axial direction.

Images