Spindle cooling system combining spindle and surface circuits

Abstract

This invention provides a spindle cooling device that combines a core and surface cooling circuit. This innovative structure adds a cooling channel integrating the core and surface of the spindle's mandrel portion. Coolant supplied by an oil cooler enters this cooling channel, effectively removing heat generated by the motor rotor, front bearing, and rear bearing, reducing the overall temperature rise of the spindle, and minimizing axial thermal elongation of the mandrel. This effectively removes heat from the motor rotor, front bearing, and rear bearing, solving the problem of overall spindle temperature rise.

Description

Technical Field

[0001] This invention relates to spindle technology, and in particular to a spindle cooling device that combines a spindle core and surface circuitry. Prior Technology

[0002] Patent TW201726301A describes an internal cooling circuit for a spindle assembly, including a bushing, a liner, and a tie rod. An internal cooling channel is formed within the shaft bore. When coolant is introduced into the shaft bore and flows along the axis towards the inner end, the inner sides of the tie rod unit and the liner unit are cooled. When the coolant flows into the external cooling channel through the drainage hole, it further cools the outer side of the liner unit and the shaft assembly, increasing the cooling surface area and producing a better cooling effect. However, the increased cooling range of this design is limited by the structure, which only extends to the periphery of the liner and cannot cover the entire spindle.

[0003] The cooling circuit designed in patent EP1736277A2 is located inside the spindle shaft, featuring a hollow cylindrical spindle shaft with a connecting rod inside. Multiple input and output holes are located axially along the spindle shaft. When the spindle is running, coolant enters through the input holes and exits in the opposite direction through the output holes to achieve a cooling effect. However, this design requires cavity drilling for the input and output holes, which can easily damage the drilling tools. It is more suitable for shorter spindles and suffers from high machining difficulty, difficulty in mass production, and high production costs. Furthermore, the cooling circuit is located far from the heat source of the motor rotor, limiting its cooling effect. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a spindle cooling device that combines a spindle core and a surface circuit, the cooling range of which covers the entire spindle core, effectively removing the heat generated by the motor rotor, the front bearing and the rear bearing, and reducing the overall temperature rise of the spindle.

[0005] To achieve the above objectives, the present invention provides a spindle cooling device combining a spindle core and surface circuits, comprising a spindle having a rear shaft portion, a central shaft portion, and a front shaft portion. The central shaft portion is connected to the rear shaft portion, and the front shaft portion is connected to the other end of the central shaft portion opposite to the rear shaft portion. The rear shaft portion has a rear shaft outer periphery, a rear discharge hole, and a rear return hole. The rear discharge hole allows coolant to enter, and the rear return hole allows coolant to exit. The central shaft portion has a central shaft outer periphery, a central discharge groove, and a central return groove. The central discharge groove and the central return groove are respectively disposed on the surface of the central shaft outer periphery. The groove communicates with the rear return hole via a through hole, and the middle return groove communicates with the rear return hole via a through hole; the front shaft portion has a front shaft outer periphery, a front return hole, a front return hole, and a return flow groove, the front return hole communicates with the middle return groove via a through hole, the front return hole communicates with the middle return groove via a through hole, and the return flow groove connects the front return hole and the front return hole; a bushing has a sleeve hole fitted onto the central shaft portion of the spindle, the sleeve hole sealingly isolating the middle return groove and the middle return groove of the spindle; a return ring has a return sealing hole fitted onto the front shaft portion of the spindle, sealing the return flow groove of the spindle.

[0006] By means of the above technical features, the spindle cooling device of the present invention, which combines the spindle core and surface circuit, forms a cooling circuit through the rear deflection hole, the middle deflection groove, the front deflection hole, the return flow groove, the front return hole, the middle return groove, and the rear return hole. Its cooling range covers the entire spindle core, effectively removing the heat generated by the motor rotor, the front bearing and the rear bearing, and reducing the overall temperature rise of the spindle.

[0007] Preferably, the rear return hole extends into the central shaft portion, and the rear return hole extends into the central shaft portion.

[0008] Preferably, the forward hole extends into the central shaft portion, and the forward return hole extends into the central shaft portion.

[0009] Preferably, the width of the central groove of the mandrel is greater than its depth, and the width of the central return groove of the mandrel is greater than its depth.

[0010] Preferably, it further includes two first sealing rings. A first annular groove is formed on each side of the central groove and the central return groove on the outer periphery of the central shaft portion, for mounting the first sealing rings respectively. The bushing is sealed to the first sealing rings.

[0011] Preferably, it further includes two second sealing rings. The front axle portion has a second annular groove on each side of its return groove, for mounting the second sealing rings respectively. The return sealing hole of the return ring is sealed and fitted onto the second sealing rings.

[0012] Preferably, the diameter of the rear hole of the mandrel is larger than the diameter of the front hole.

[0013] Preferably, the distance from the rear hole of the mandrel to the outer periphery of the rear shaft is greater than the distance from the front hole to the outer periphery of the front shaft.

[0014] Preferably, the diameter of the back return hole of the mandrel is larger than the diameter of the front return hole.

[0015] Preferably, the distance from the rear return hole to the outer periphery of the rear shaft is greater than the distance from the front return hole to the outer periphery of the front shaft.

[0016] The detailed structure, features, and usage of the spindle cooling device combining the spindle core and surface circuits provided by this invention will be described in the subsequent detailed description of the embodiments. However, those skilled in the art should understand that such detailed descriptions and the specific embodiments listed for implementing this invention are merely illustrative and not intended to limit the scope of this patent application. Simple Explanation of the Diagram

[0017] The following description, using examples and accompanying drawings, further illustrates the spindle cooling device combining the shaft center and surface circuitry provided by the present invention, wherein:

[0018] Figure 1 is a three-dimensional assembly diagram of a preferred embodiment of the present invention. Figure 2 is a cross-sectional view along the secant line 2-2 in Figure 1. Figure 3 is a perspective view of a mandrel according to a preferred embodiment of the present invention. Figure 4 is a perspective view of the mandrel in another direction according to a preferred embodiment of the present invention. Figure 5 is a cross-sectional view along the secant line 5-5 in Figure 3. Figure 6 is a perspective view of a bushing according to a preferred embodiment of the present invention. Figure 7 is a perspective view of the reflux ring of a preferred embodiment of the present invention. Figure 8 is a perspective view of the reflux ring of a preferred embodiment of the present invention from another direction. Implementation

[0019] First, it should be noted that the technical features provided by this invention are not limited to the specific structures, uses, and applications described in the embodiments. All terms used in the description are illustrative descriptive terms that can be understood by those skilled in the art. The directional terms such as "front," "up," "down," "back," "left," "right," "top," "bottom," "inner," and "outer" mentioned in this specification are merely illustrative descriptive terms based on normal usage directions and are not intended to limit the scope of the claims.

[0020] Please refer to Figures 1 to 8. A preferred embodiment of the present invention provides a spindle cooling device 1 that combines a spindle and a surface circuit, comprising a spindle 10, four first sealing rings R1, two second sealing rings R2, a bushing 20, and a return ring 30.

[0021] The spindle 10 has a rear shaft portion 11, a central shaft portion 12, and a front shaft portion 13. The central shaft portion 12 is connected to the rear shaft portion 11, and the front shaft portion 13 is connected to the other end of the central shaft portion 12 opposite to the rear shaft portion 11. The rear shaft portion 11 and the front shaft portion 13 are mainly for mounting the bearing 50, and the central shaft portion 12 is mainly for mounting the rotor 60.

[0022] The rear axle portion 11 has a rear axle outer periphery 111, four rear exit holes 113, and four rear return holes 114. The rear exit holes 113 extend into the central axle portion 12, and the rear return holes 114 extend into the central axle portion 12. The rear exit holes 113 allow coolant to enter, and the rear return holes 114 allow coolant to exit. The rear exit holes 113 and the rear return holes 114 are arranged circumferentially and spaced apart.

[0023] In this embodiment, the diameter of the rear hole 113 is larger than the diameter of the front hole 133, and the distance from the rear hole 113 to the outer periphery 111 of the rear axle is greater than the distance from the front hole 133 to the outer periphery 131 of the front axle.

[0024] The central shaft portion 12 is connected to the rear shaft portion 11. The central shaft portion 12 has a central shaft outer periphery 121, four central deflection grooves 123, four central return grooves 124, and a plurality of first annular grooves 127. The central deflection grooves 123 and the central return grooves 124 are circumferentially spaced apart on the surface of the central shaft outer periphery 121. The central deflection grooves 123 communicate with the rear deflection hole 113 through a through hole 125, the central return grooves 124 communicate with the rear return hole 114 through a through hole 125, and the first annular grooves 127 are arranged around the central shaft outer periphery 121.

[0025] In this embodiment, the width of the central groove 123 of the mandrel 10 is greater than its depth, and the width of the central return groove 124 of the mandrel 10 is greater than its depth.

[0026] The front axle portion 13 is connected to the other end of the central axle portion 12 opposite to the rear axle portion 11. The front axle portion 13 has a front axle outer periphery 131, four forward exit holes 133, four forward return holes 134, four return flow grooves 135, and two second annular grooves 137. The forward exit holes 133 and the forward return holes 134 are arranged circumferentially and spaced apart. The forward exit holes 133 extend into the central axle portion 12, and the forward return holes 134 extend into the central axle portion 12. The forward exit holes 133 and the central exit groove 123 communicate with each other through a through hole 125. The forward return holes 134 and the central return groove 124 communicate with each other through a through hole 125. The return flow grooves 135 connect adjacent forward exit holes 133 and forward return holes 134 respectively. The second annular grooves 137 are located on both axial sides of the return flow grooves 135.

[0027] In this embodiment, the diameter of the rear return hole 114 is larger than the diameter of the front return hole 134, and the distance from the rear return hole 114 to the outer periphery of the rear axle 111 is greater than the distance from the front return hole 134 to the outer periphery of the front axle 131.

[0028] The first sealing ring R1 is installed in the first annular groove 127 of the central shaft portion 12 of the spindle 10.

[0029] The second sealing ring R2 is installed in the second annular groove 137 of the front shaft portion 13 of the spindle 10.

[0030] The bushing 20 has a bushing 21, which is tightly fitted onto the outer periphery 121 of the central shaft portion 12 of the spindle 10. The bushing 21 seals the central groove 123 and the central return groove 124 of the central shaft portion 12 of the spindle 10, so that the central groove 123 and the central return groove 124 will not leak and will not communicate with each other, and each forms a flow channel. The bushing 21 is also sealed on both sides of each first sealing ring R1.

[0031] A return ring 30 is installed on the spindle 10, and the return ring 30 has a return sealing hole 31. The return sealing hole 31 seals each return groove 135 of the spindle 10, preventing communication between the return grooves 135 of the spindle 10. The return sealing hole 31 of the return ring 30 is sealed and fitted onto each second sealing ring R2.

[0032] The rear discharge hole 113, rear return hole 114, middle discharge groove 123, middle return groove 124, front discharge hole 133, front return hole 134, return flow groove 135 and through hole 125 are connected to form a cooling circuit.

[0033] In this embodiment, the coolant enters the spindle cooling circuit through the rotary module, enters the spindle 10 through the cooling holes, and flows towards the front end of the main spindle. First, it flows past the rear bearing 50 for cooling. When it reaches near the motor rotor 60, it flows through the channel to the surface of the spindle 10, entering the groove channel formed by the spindle 10 surface and the bushing unit to cool the inner diameter surface of the motor rotor 60. Then, as it leaves the motor rotor 60, it flows through the channel back to the front bearing 50 for cooling. Finally, the coolant in the cooling channel flows through the spindle 10 channel to the front end of the main spindle to cool the nose of the spindle 10, and then flows back through the groove formed by the spindle 10 surface and the return ring 30 to the spindle 10 channel. During the return flow, it again passes through the front bearing 50, the motor rotor 60, and the rear bearing 50 for cooling, and finally leaves the main spindle through the rotary module, returning to the cooling machine. The direction of the main spindle cooling circuit is shown in the attached figure.

[0034] Regarding patent avoidance, unlike patents TW201726301A and EP1736277A2 related to spindle cooling, the novel spindle cooling channel designed in this invention features elongated grooved channels on the surface of the spindle 10, which are connected by drilling. This channel circuit is located on the surface of the spindle 10, closer to the heat source of the motor rotor 60, and its cooling range covers the entire spindle 10, thus more effectively removing heat and achieving superior cooling efficiency. Furthermore, this design not only makes the machining of the entire cooling channel circuit easier and improves cooling efficiency, but also reduces manufacturing costs, making the product more competitive and potentially giving it a competitive edge in the market.

[0035] In terms of the spindle design, coolant inlet and outlet holes are provided at the rear of the spindle, allowing coolant to effectively enter and exit the spindle. Grooves are designed at the contact point between the spindle surface and the motor rotor bushing 20 to effectively remove the heat generated by the rotor 60. At the same time, a return groove is designed on the front surface of the spindle, allowing the coolant to turn and flow back at the front of the spindle. In addition, the internal design of the spindle is to form flow channels by drilling, and the surface grooves are connected to the internal flow channels through the drilling, connecting the coolant inlet and outlet holes to ensure that the coolant can flow smoothly inside the spindle, thus achieving the purpose of the present invention.

[0036] By using the larger diameter of the rear return hole 113 than the front return hole 133, and the larger diameter of the rear return hole 114 than the front return hole 134, different flow velocities can be generated. Since the coolant temperature has slightly increased after passing through, the smaller hole diameter allows for a faster flow velocity, thus carrying away heat more quickly. Furthermore, the greater distance between the rear return hole 114 and the outer circumference of the rear shaft 111 than the greater distance between the front return hole 134 and the outer circumference of the front shaft 131, and the greater distance between the rear return hole 113 and the outer circumference of the rear shaft 111 than the greater distance between the front return hole 133 and the outer circumference of the front shaft 131, along with the greater proximity of the rear return hole 113 to the outer circumference of the rear shaft, also allows for faster heat removal. Therefore, the cooling of the entire spindle can be more evenly distributed across the front, middle, and rear sections.

[0037] In addition to the above-described embodiments, the present invention can also be implemented in variations as follows, while still achieving the purpose of the present invention.

[0038] For example, the number of rear exit holes 113 and rear return holes 114 of the spindle 10 is not limited to four as mentioned above; the number of middle exit grooves 123 and middle return grooves 124 of the spindle 10 is not limited to four as mentioned above; and the number of front return holes 134 and front exit holes 133 of the spindle 10 is not limited to four as mentioned above. They can also be changed to one each, or two each, or three each, or five each, or six each, etc.

[0039] In summary, the spindle cooling device combining the shaft and surface circuit of the present invention has indeed achieved the purpose of the present invention through the above implementation description.

[0040] 10: Mandrel 11: Rear axle section 111: Rear axle outer circumference 113: After removing the hole 114: Backhole 12: Central axis section 121: Outer periphery of the central axis 123: Middle of the groove 124: Intermediate return groove 125: Through hole 127: First Ring Ditch 13: Front axle section 131: Front axle outer periphery 133: Go to Kong 134: Front return hole 135: Reflux channel 137: Second Ring Ditch 20: Bushing 21: Sleeve hole 30: Reflux ring 31: Reflow sealing 50: Bearing 60: Rotor R1: First sealing ring R2: Second sealing ring

Claims

1. A spindle cooling device combining a spindle core and surface circuits, comprising: A spindle has a rear shaft portion, a central shaft portion, and a front shaft portion. The central shaft portion is connected to the rear shaft portion, and the front shaft portion is connected to the other end of the central shaft portion opposite to the rear shaft portion. The rear shaft portion has a rear shaft outer circumference, a rear outlet hole, and a rear return hole. The rear outlet hole allows coolant to enter, and the rear return hole allows coolant to exit. The central shaft portion has a central shaft outer circumference, a central outlet groove, and a central return groove. The central outlet groove and the central return groove are respectively provided on the surface of the central shaft outer circumference. The central outlet groove communicates with the rear outlet hole through a through hole, and the central return groove communicates with the rear return hole through a through hole. The front shaft portion has a front shaft outer circumference, a front outlet hole, a front return hole, and a return flow groove. The front outlet hole communicates with the central outlet groove through a through hole, and the front return hole communicates with the central return groove through a through hole. The return flow groove connects the front outlet hole and the front return hole. The central groove and the central return groove are arranged axially; a bushing has a sleeve hole that fits onto the central shaft portion of the mandrel, the sleeve hole sealingly isolating the central groove and the central return groove of the mandrel; And a return ring having a set of return sealing holes on the front shaft portion of the mandrel to seal the return groove of the mandrel; wherein the width of the central groove of the mandrel is greater than its depth, and the width of the central return groove of the mandrel is greater than its depth; wherein the diameter of the rear hole of the mandrel is greater than the diameter of the front hole; wherein the distance from the rear hole of the mandrel to the outer periphery of the rear shaft is greater than the distance from the front hole to the outer periphery of the front shaft; wherein the diameter of the rear return hole of the mandrel is greater than the diameter of the front return hole; wherein the distance from the rear return hole of the mandrel to the outer periphery of the rear shaft is greater than the distance from the front return hole to the outer periphery of the front shaft.

2. The spindle cooling device combining the spindle and surface circuit as described in claim 1, wherein the rear return hole extends into the central shaft portion and the rear return hole extends into the central shaft portion.

3. The spindle cooling device combining the spindle and surface circuit as described in claim 1, wherein the forward return hole extends into the central shaft portion and the forward return hole extends into the central shaft portion.

4. The spindle cooling device combining the spindle core and surface circuit as described in claim 1, further comprising two first sealing rings, wherein a first annular groove is formed on each side of the central shaft outer periphery of the central shaft portion, on both sides of the central return groove and the central return groove, for mounting the first sealing rings respectively, and the bushing is sealed to the first sealing rings.

5. The spindle cooling device combining the shaft and surface circuit as described in claim 1, further comprising two second sealing rings, wherein the front shaft portion has a second annular groove on each side of its return groove for mounting the second sealing rings respectively, and the return sealing hole of the return ring is sealedly fitted onto the second sealing rings.

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