HORIZONTAL COMPUTER NUMERICAL CONTROL (CNC) MACHINING DEVICE FOR CRANKSHAFT

A horizontal computer numerical control (CNC) machining device for a crankshaft includes a horizontal machining workbench provided thereon with the crankshaft and a milling spindle adjusting device provided on a side of the horizontal machining workbench along a length direction of the crankshaft. A milling spindle is fixedly provided on the milling spindle adjusting device, and the milling spindle adjusting device includes an X-axis adjusting mechanism, a Y-axis adjusting mechanism, and a Z-axis adjusting mechanism, which are configured to adjust the spatial position of the milling spindle relative to the crankshaft. The horizontal machining workbench is provided thereon with a C-axis headstock configured to drive the crankshaft to rotate. The horizontal CNC machining device can mill on an outside diameter of a crankshaft or a diameter of an eccentric shaft, and can mill, drill, bore, or tap an outer surface of a workpiece through X, Y, and Z-axis feeding movement.

TECHNICAL FIELD

The present invention relates to the technical field of crankshaft machining devices and, in particular, to a horizontal computer numerical control (CNC) machining device for a crankshaft.

BACKGROUND

In a general piston engine, as a key component for transferring kinetic energy, the crankshaft is provided to convert the reciprocating motion of the piston into rotational motion to output the power of the engine. Heavy-duty crankshafts with complex shapes require high machining accuracy to ensure their ability to withstand torque, bending moment, and dynamic load. There is a great demand for heavy-duty crankshafts, so they must be produced in large quantities. However, for professional crankshaft manufacturers, the prior horizontal machining devices are manually operated with high labor intensity, low machining efficiency, and poor versatility and must adopt dedicated eccentric fixtures for turning. In addition, the machine tool is unable to achieve continuous cutting of the side of the crankshaft journal, resulting in many empty feeds, and each type of crankshaft requires a corresponding dedicated fixture. This greatly increases the input cost of equipment and human resources, and it is still hard to effectively ensure the dimensional accuracy of the crankshaft.

SUMMARY

An objective of the present invention is to provide a horizontal CNC machining device for a crankshaft. The present invention can mill on an outside diameter of a crankshaft or a diameter of an eccentric shaft and can mill, drill, bore, or tap an outer surface of a workpiece through X, Y, and Z-axis feeding movement.

To achieve the above objective, the present application provides the following technical solution. The horizontal CNC machining device for a crankshaft includes a horizontal machining workbench provided thereon with the crankshaft and a milling spindle adjusting device provided on a side of the horizontal machining workbench along the length direction of the crankshaft. The milling spindle adjusting device is fixedly provided thereon with a milling spindle, and the milling spindle adjusting device includes an X-axis adjusting mechanism, a Y-axis adjusting mechanism, and a Z-axis adjusting mechanism. The X-axis adjusting mechanism, the Y-axis adjusting mechanism, and the Z-axis adjusting mechanism are perpendicular to each other and are configured to adjust the positions of the milling spindle relative to the crankshaft along an X-axis, a Y-axis, and a Z-axis, respectively. The horizontal machining workbench is provided thereon with a C-axis headstock configured to drive the crankshaft to rotate. The C-axis headstock is provided with a position locking mechanism. The position locking mechanism is configured to lock a peripheral position of the crankshaft relative to the milling spindle and includes an encoder assembly configured to feed back a detection signal and a brake assembly configured to lock the crankshaft. The C-axis headstock is provided therein with a controller configured to control the brake assembly to perform a corresponding action according to the detection signal fed back by the encoder assembly.

Preferably, the X-axis adjusting mechanism includes an X-axis moving base provided along the length direction of the crankshaft. The Y-axis adjusting mechanism includes a first pillar slidably connected to the X-axis moving base, and a Y-axis moving slide plate is slidably connected to the first pillar. The Z-axis adjusting mechanism includes a Z-axis ram slidably connected to the Y-axis moving slide plate. The milling spindle is provided on the Z-axis ram.

Preferably, the X-axis adjusting mechanism includes a first servo motor provided on a side of the X-axis moving base. The X-axis moving base is provided thereon with a first screw rod connected to an output end of the first servo motor. The bottom of the first pillar is provided with a first internal thread sleeve mated with the first screw rod. The first internal thread sleeve is sleeved outside the first screw rod. The Y-axis adjusting mechanism includes a second servo motor provided on the top of the first pillar, and the second servo motor has an output end connected to a second screw rod. The Y-axis moving slide plate is provided with a second internal thread sleeve, and the second internal thread sleeve is sleeved outside the second screw rod. The Z-axis adjusting mechanism includes a third servo motor fixedly provided on the Y-axis moving slide plate, and the third servo motor has an output end connected to a third screw rod. The Z-axis ram is provided with a third internal thread sleeve, and the third internal thread sleeve is sleeved outside the third screw rod. The Z-axis adjusting mechanism further includes a fourth motor provided at a side of the Z-axis ram away from the milling spindle.

Preferably, the horizontal machining workbench further includes a tailstock, and the tailstock is provided at a side of the crankshaft away from the C-axis headstock to define a central position of the crankshaft. The tailstock is provided with a center rotatably connected to the crankshaft.

Preferably, the horizontal machining workbench includes a workbench body. The workbench body is provided thereon with a first slide rail at a side of the tailstock. The tailstock is slidably connected to the first slide rail through a tailstock base. The tailstock base is provided thereon with a first locking element configured to fix the tailstock to the first slide rail.

Preferably, the horizontal machining workbench further includes a central carrier provided on the workbench body and configured to support a journal of the crankshaft.

Preferably, the central carrier is slidably connected to the workbench body, and the bottom of the central carrier is provided with a second locking element configured to fix the central carrier to the workbench body.

Preferably, the C-axis headstock further includes a drive shaft connected to the crankshaft and a drive assembly configured to control the speed of the drive shaft.

Preferably, the drive assembly includes a fifth servo motor, and the fifth servo motor is connected to a headstock timing pulley through a conveyor belt. The headstock timing pulley is connected to the drive shaft through a transmission shaft. The transmission shaft is connected to a transmission case.

Preferably, the encoder assembly includes an encoder connected to the drive shaft through an encoder timing pulley, and the encoder has an output end electrically connected to the controller. The brake assembly includes a brake pad fixedly provided on the drive shaft. The C-axis headstock is provided with a brake caliper mated with the brake pad to lock the brake pad, and an output end of the controller is connected to the brake caliper.

In the present invention, the milling spindle adjusting device adjusts the spatial position of the milling spindle relative to the crankshaft, such that machining is performed at different positions of the crankshaft. The position locking mechanism is provided to facilitate the machining of the crankshaft at a specified angle. The position locking mechanism includes the encoder assembly configured to control a locking angle, and the encoder assembly is mated with the controller to control the locking angle. The brake assembly locks the crankshaft at the specified angle. There are two machining modes, which improve machining efficiency.

The tailstock and the central carrier reliably support and position the crankshaft. Through the first locking element and the second locking element, the central carrier and the tailstock can be axially moved and fastened on the workbench body according to the workpiece, which improves the versatility of the machining device.

The C-axis headstock is provided with the drive assembly to control the speed of the drive shaft, thus improving machining accuracy.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The technical solutions of the embodiments of the present invention are clearly and completely described below by referring to the drawings. The described embodiments are merely a part, rather than all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts should fall within the protection scope of the present invention.

As shown inFIG.1, a first embodiment of the present invention provides a horizontal CNC machining device for crankshaft2that includes horizontal machining workbench1. The horizontal machining workbench1is provided thereon with the crankshaft2. The horizontal CNC machining device further includes milling spindle adjusting device3provided on a side of the horizontal machining workbench1along a length direction of the crankshaft2. The milling spindle adjusting device3is fixedly provided thereon with milling spindle331. The milling spindle adjusting device3includes X-axis adjusting mechanism31, Y-axis adjusting mechanism32, and Z-axis adjusting mechanism33and configured to adjust the spatial position of the milling spindle331relative to the crankshaft2. The horizontal machining workbench1is provided thereon with C-axis headstock12configured to drive the crankshaft2to rotate. The milling spindle adjusting device3adjusts the three-dimensional position of the milling spindle331relative to the crankshaft2, such that machining is performed at different positions of the crankshaft2. The C-axis headstock12drives the workpiece to rotate to realize rotational feeding movement. The milling spindle331is provided with a milling cutter and configured to perform the cutting movement to realize outside diameter milling, eccentric shaft diameter milling, and opening milling of a shaft part.

As shown inFIG.2, the X-axis adjusting mechanism31includes X-axis moving base310provided along the length direction of the crankshaft2. The Y-axis adjusting mechanism32includes first pillar320slidably connected to the X-axis moving base310. The first pillar320is slidably connected to Y-axis moving slide plate321. The Z-axis adjusting mechanism33includes Z-axis ram330slidably connected to the Y-axis moving slide plate321. The milling spindle331is provided on the Z-axis ram330. The X-axis adjusting mechanism31includes first servo motor311provided on a side of the X-axis moving base310. The X-axis moving base310is provided with first screw rod312. The first screw rod312is connected to an output end of the first servo motor311. The bottom of the first pillar320is provided with first internal thread sleeve313mated with the first screw rod312, and the first internal thread sleeve313is sleeved outside the first screw rod312. The Y-axis adjusting mechanism32includes second servo motor322provided on the top of the first pillar320. An output end of the second servo motor322is connected to second screw rod323.

As shown inFIGS.3and4, the Y-axis moving slide plate321is provided with second internal thread sleeve324, and the second internal thread sleeve324is sleeved outside the second screw rod323. The Z-axis adjusting mechanism33includes third servo motor332fixedly provided on the Y-axis moving slide plate321. An output end of the third servo motor332is connected to a third screw rod333. The Z-axis ram330is provided with third internal thread sleeve334, and the third internal thread sleeve334is sleeved outside the third screw rod333. The Z-axis adjusting mechanism33further includes fourth motor6provided at a side of the Z-axis ram330away from the milling spindle331and configured to drive the milling spindle331to rotate. Specifically, the Y-axis moving slide plate321has an L-shaped structure and includes vertical part3211and bending part3212. The vertical part3211is provided with first slide groove3213, and the Z-axis ram330is provided with first slider3215mated with the first slide groove3213. The bending part3212is provided with second slide groove3214, and the Z-axis ram330is provided with second slider3216mated with the second slide groove3214. The Z-axis ram330can slide along an axial direction of the milling spindle331on the Y-axis moving slide plate321, and the Y-axis moving slide plate321with the L-shaped structure increases the sliding stability of the Z-axis ram330.

As shown inFIG.5, the horizontal machining workbench1further includes tailstock13. The tailstock13is symmetrical with the C-axis headstock12and is provided on the other side of the crankshaft2to define a central position of the crankshaft2. The tailstock13is provided with center1301. The center1301is rotatably connected to the crankshaft2. One end of the crankshaft2is connected to drive shaft4of the C-axis headstock12through flange5. Multiple keys401are provided at a side of the drive shaft4connected to the flange5. The flange5is provided with a keyway mated with the keys for increasing the coupling torque of the drive shaft4and the flange5. The horizontal machining workbench1includes workbench body11. The workbench body11is provided with first slide rail1101at a side of the tailstock13. The tailstock13is slidably connected to the first slide rail1101through tailstock base1302. The tailstock base1302is provided with first locking element1303configured to fix the tailstock13to the first slide rail1101. The horizontal machining workbench1further includes central carrier14provided on the workbench body11and configured to support a journal of the crankshaft2. The central carrier14is slidably connected to the workbench body11. The bottom of the central carrier14is provided with second locking element1401configured to fix the central carrier14to the workbench body11. The tailstock13and the central carrier14reliably support and position the crankshaft2. Through the first locking element1303and the second locking element1401, the central carrier14and the tailstock13can be axially moved and fastened on the workbench body11according to the workpiece, which improves the versatility of the machining device.

As shown inFIGS.6to8, the C-axis headstock12further includes the drive shaft4connected to the crankshaft2and drive assembly140configured to control the speed of the drive shaft4. The drive assembly140includes fifth servo motor1401. The fifth servo motor1401is connected to headstock timing pulley1403through conveyor belt1402. The headstock timing pulley1403is connected to the drive shaft4through transmission shaft1404. The transmission shaft1404is connected to the transmission case. Brake assembly130includes brake pad1301fixedly provided on the drive shaft4. The C-axis headstock12is provided with brake caliper1302mated with the brake pad1301to lock the brake pad1301. The brake caliper1302is provided with jaw1303mated with the brake pad1301to clamp the brake pad1301. An output end of a controller is connected to the brake caliper1302. The controller is provided in the C-axis headstock12. Encoder assembly120includes encoder1202connected to the drive shaft4through encoder timing pulley1201. An output end of the encoder1202is electrically connected to the controller. The encoder1202can convert an angular displacement into an electrical signal. The encoder1202converts a rotation angle of the drive shaft4into a pulse count and sends the pulse count to the controller. The controller has a first preset value. When the pulse count sent to the controller by the encoder1202reaches a value corresponding to the first preset value, it means that the drive shaft4already drives the crankshaft2to rotate to a designated position. At this time, the controller controls the brake caliper1302to clamp the brake pad1301to lock the crankshaft2.

The C-axis headstock12is provided with the drive assembly140to control the speed of the drive shaft4to perform outside diameter milling of the shaft part at different speeds, thus improving the machining accuracy. A position locking mechanism is provided to facilitate the machining of the crankshaft2at a specified angle. The position locking mechanism includes the encoder assembly120configured to control a locking angle, and the encoder assembly120is mated with the controller to control the locking angle. The brake assembly130locks the crankshaft2at the specified angle. After the crankshaft2is locked, the X, Y, and Z-axis feeding movements are realized through the milling spindle adjusting device3. The fourth motor6drives the milling spindle331to rotate to complete machinings such as milling, drilling, boring, and tapping, which improves the applicability and machining efficiency of the machining device.

The working principle of the machining device is as follows. The tailstock13on the horizontal machining workbench1is adjusted by axial movement. The crankshaft2to be machined is placed on the horizontal machining workbench1. One end of the crankshaft2is connected to the drive shaft4of the C-axis headstock12through the flange5, and the other end of the crankshaft2is connected to the center1301of the tailstock13. The central carrier14is adjusted by the axial movement to support the journal of the crankshaft2, thus realizing the mounting of the crankshaft2.

To mill the surface of crankshaft2, the C-axis headstock12drives crankshaft2to rotate, and the X-axis adjusting mechanism31, the Y-axis adjusting mechanism32, and the Z-axis adjusting mechanism33adjust the three-dimensional position of the milling spindle331. To perform drilling, boring, or tapping, the position locking mechanism controls the brake caliper1302to clamp the brake pad1301, such that the crankshaft2is locked at a specified angle, and then the fourth motor6and the third servo motor332are controlled to operate.

The tailstock13and the central carrier14reliably support and position the crankshaft2. Through the first locking element1303and the second locking element1401, the central carrier14and the tailstock13can be axially moved and fastened on the workbench body11according to the workpiece, which improves the versatility of the machining device.

The headstock timing pulley1403is connected to the drive shaft4through the transmission shaft1404, and the transmission shaft1404is connected to the transmission case. The high and low-speed gears is switched in the transmission case through a shifting lever to switch between high and low speeds to perform turning at high speed and milling at low speed. The servo motor is configured to drive to achieve fine milling of the crankshaft2.

It is apparent to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention may be implemented in other specific forms without departing from the spirit or basic features of the present invention. The embodiments should be regarded as exemplary and non-limiting in every respect, and the scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of equivalent elements of the claims should be included in the present invention. Any reference numerals in the claims should not be considered as limiting the claims involved.