Spindle lubrication device for a machine tool, machine tool and method of using a machine tool

Abstract

The present application provides a spindle lubrication device of a machine tool, a machine tool, and a method for using the machine tool. The spindle lubrication device of the machine tool includes a rotating body that holds a tool, a plurality of bearings, a housing, a mixed fluid supply device, and a recovery device that recovers an oil-containing fluid. The recovery device includes a plurality of recovery flow passages, a plurality of injectors, and a plurality of flow control valves. The plurality of injectors includes a first injector that generates a negative pressure using first air supplied from a first air flow passage, thereby attracting a first oil-containing fluid from a first recovery flow passage, and a second injector that generates a negative pressure using second air supplied from a second air flow passage, thereby attracting a second oil-containing fluid from a second recovery flow passage. The plurality of flow control valves includes a first flow control valve that adjusts a flow rate of the first air supplied from the first air flow passage to the first injector, and a second flow control valve that adjusts a flow rate of the second air supplied from the second air flow passage to the second injector.

Description

Technical Field

[0001] This invention relates to a spindle lubrication device for a machine tool, a machine tool, and a method of using the machine tool. Background Technology

[0002] A lubrication device for the spindle of a machine tool is known.

[0003] As a related technology, Patent Document 1 discloses a spindle lubrication device. In the spindle lubrication device described in Patent Document 1, the rotating shaft is rotatably supported on the housing by means of bearings, and the bearings are lubricated by lubricating oil supplied from the outside. Furthermore, in the spindle lubrication device described in Patent Document 1, the discharged oil is attracted by negative pressure by a negative pressure generating device, or the discharged oil is recovered by natural falling.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2016-002622 Summary of the Invention

[0005] The purpose of this invention is to provide a technique that prevents poor lubrication in multiple bearings.

[0006] In some embodiments, a spindle lubrication device for a machine tool includes: a rotating body holding a cutting tool; a plurality of bearings, including a first bearing and a second bearing; a housing supporting the rotating body via the plurality of bearings for rotation about a first axis; a mixed fluid supply device supplying a mixed fluid comprising oil and air to the plurality of bearings; and a recovery device for recovering the oil-containing fluid. The recovery device includes: a plurality of recovery channels disposed within the housing for recovering the oil-containing fluid from the plurality of bearings; a plurality of ejectors disposed outside the housing; and a plurality of flow control valves. The plurality of recovery channels includes: a first recovery channel primarily recovering the first oil-containing fluid discharged from at least one bearing including the first bearing; and a second recovery channel primarily recovering the second oil-containing fluid discharged from at least one bearing including the second bearing. The plurality of ejectors includes: a first ejector generating a negative pressure using first air supplied from a first air channel, thereby drawing the first oil-containing fluid from the first recovery channel; and a second ejector generating a negative pressure using second air supplied from a second air channel, thereby drawing the second oil-containing fluid from the second recovery channel. The plurality of flow control valves include: a first flow control valve for adjusting the flow rate of the first air supplied from the first air passage to the first injector; and a second flow control valve for adjusting the flow rate of the second air supplied from the second air passage to the second injector.

[0007] In some embodiments, the machine tool includes: a machining head having: a rotating body holding a cutting tool; a plurality of bearings, including a first bearing and a second bearing; a housing supporting the rotating body for rotation via the plurality of bearings; a first rotary drive for rotating the rotating body about a first axis; a mixed fluid supply device supplying a mixed fluid comprising oil and air to the plurality of bearings; a recovery device for recovering the oil-containing fluid; a workpiece support for supporting a workpiece; a moving device for moving the machining head relative to the workpiece support; and a control device controlling at least the first rotary drive, the mixed fluid supply device, and the moving device. The recovery device includes: a plurality of recovery channels disposed in the housing for recovering the oil-containing fluid from the plurality of bearings; a plurality of ejectors disposed outside the housing; and a plurality of flow control valves. The plurality of recovery channels include: a first recovery channel primarily recovering a first oil-containing fluid discharged from at least one bearing including the first bearing; and a second recovery channel primarily recovering a second oil-containing fluid discharged from at least one bearing including the second bearing. The plurality of injectors includes: a first injector that generates a negative pressure using first air supplied from a first air passage, thereby drawing the first oil-containing fluid from the first recovery passage; and a second injector that generates a negative pressure using second air supplied from a second air passage, thereby drawing the second oil-containing fluid from the second recovery passage. The plurality of flow control valves includes: a first flow control valve that adjusts the flow rate of the first air supplied from the first air passage to the first injector; and a second flow control valve that adjusts the flow rate of the second air supplied from the second air passage to the second injector.

[0008] Some embodiments of the machine tool are methods of using the machine tool described above. This method includes: a step of determining or simulating the first discharge flow rate when, under a second condition where multiple pipes are fluidly separated from multiple recovery channels and a mixed fluid of a first flow rate is supplied from the mixed fluid supply device to multiple bearings, the flow rate of the first oil-containing fluid discharged from the first recovery channel to the outside of the first recovery channel is defined as a first discharge flow rate; a step of determining or simulating the second discharge flow rate when, under the second condition, the flow rate of the second oil-containing fluid discharged from the second recovery channel to the outside of the second recovery channel is defined as a second discharge flow rate; and a step of determining or simulating the first discharge flow rate when, under a first condition where multiple pipes are fluidly connected to the multiple recovery channels and a mixed fluid of the first flow rate is supplied from the mixed fluid supply device to the multiple bearings, the flow rate of the first oil-containing fluid flowing in the first pipe is defined as a first recovery flow rate, and the first discharge flow rate is determined by determining or simulating the first discharge flow rate. The process includes: deriving the first recovery flow rate through simulation; deriving the second recovery flow rate by measurement or simulation when the flow rate of the second oil-containing fluid flowing in the second pipe is defined as the second recovery flow rate under the first condition; deriving the first opening degree of the first flow control valve so that the ratio of the first recovery flow rate to the first discharge flow rate is within a predetermined range; deriving the second opening degree of the second flow control valve so that the ratio of the second recovery flow rate to the second discharge flow rate is within a predetermined range; supplying the mixed fluid to the plurality of bearings using the mixed fluid supply device; operating the recovery device while the opening degree of the first flow control valve is set to the first opening degree and the opening degree of the second flow control valve is set to the second opening degree; and machining the workpiece by means of the cutting tool held on the rotating body and rotating about the first axis.

[0009] According to the present invention, a technique can be provided that prevents poor lubrication in multiple bearings. Attached Figure Description

[0010] Figure 1 This is a schematic cross-sectional view of the spindle lubrication device of the machine tool in the first embodiment.

[0011] Figure 2 This is a schematic cross-sectional view of the spindle lubrication device of the machine tool in the comparative example.

[0012] Figure 3 This is a schematic cross-sectional view of the spindle lubrication device of a machine tool in a first variation of the first embodiment.

[0013] Figure 4This is a diagram schematically illustrating the measurement of the first and second recovery flow rates.

[0014] Figure 5 This diagram schematically illustrates the discharge of oil-containing fluid from the first and second recovery channels to the outside of the casing.

[0015] Figure 6 This is a schematic cross-sectional view of the spindle lubrication device of the machine tool in the first embodiment.

[0016] Figure 7 This is a schematic cross-sectional view of the spindle lubrication device of the machine tool in the second embodiment.

[0017] Figure 8 This is a diagram schematically illustrating the measurement of the first and second recovery flow rates.

[0018] Figure 9 This diagram schematically illustrates the discharge of oil-containing fluid from the first and second recovery channels to the outside of the casing.

[0019] Figure 10 This is a schematic cross-sectional view of the spindle lubrication device of the machine tool in the second embodiment.

[0020] Figure 11 This is a schematic cross-sectional view showing a portion of the spindle lubrication device of the machine tool in the second embodiment.

[0021] Figure 12 This is a diagram illustrating an example of the structure of an injector.

[0022] Figure 13 This is a schematic cross-sectional view of the spindle lubrication device of a machine tool in the first variation of the second embodiment.

[0023] Figure 14 This is a schematic cross-sectional view showing a portion of the spindle lubrication device of a machine tool in the first variation of the second embodiment.

[0024] Figure 15 This is a diagram schematically illustrating the measurement of the first and second recovery flow rates.

[0025] Figure 16 This diagram schematically illustrates the discharge of oil-containing fluid from the first, second, and third recovery channels to the outside of the casing.

[0026] Figure 17 This is a schematic cross-sectional view of the spindle lubrication device of a machine tool in the first variation of the second embodiment.

[0027] Figure 18 This is a schematic diagram showing a portion of the spindle lubrication device of a machine tool in a first variation of the second embodiment.

[0028] Figure 19 This is a schematic cross-sectional view illustrating an example of a processing head.

[0029] Figure 20 This is a schematic cross-sectional view showing a portion of the spindle lubrication device of a machine tool in the first variation of the second embodiment.

[0030] Figure 21 This is a schematic cross-sectional view showing a portion of the spindle lubrication device of a machine tool in the first variation of the second embodiment.

[0031] Figure 22 This is a schematic cross-sectional view showing a portion of the spindle lubrication device of a machine tool in the first variation of the second embodiment.

[0032] Figure 23 This is a schematic cross-sectional view showing a portion of the spindle lubrication device of a machine tool in a second variation of the second embodiment.

[0033] Figure 24 This is a schematic cross-sectional view showing a portion of the spindle lubrication device of a machine tool in the first variation of the second embodiment.

[0034] Figure 25 This is a schematic cross-sectional view showing a portion of the spindle lubrication device of a machine tool in the first variation of the second embodiment.

[0035] Figure 26 This is a diagram used to illustrate the first and second annular grooves.

[0036] Figure 27 This is a schematic perspective view illustrating an example of the machine tool in the third embodiment.

[0037] Figure 28 This is a schematic perspective view illustrating another example of the machine tool in the third embodiment.

[0038] Figure 29 This diagram schematically illustrates a situation where a control device can control multiple controlled objects.

[0039] Figure 30 This is a diagram illustrating an example of the configuration of a recycling container.

[0040] Figure 31 This is another example of a configuration used to illustrate the recycling container.

[0041] Figure 32This is a flowchart illustrating an example of how a machine tool is used in an implementation method. Detailed Implementation

[0042] Hereinafter, the spindle lubrication device 1, the machine tool 100, and the method of using the machine tool according to the embodiments will be described with reference to the accompanying drawings. In addition, in the following description of the embodiments, parts and components with the same function will be labeled with the same reference numerals, and repeated descriptions of parts and components labeled with the same reference numerals will be omitted.

[0043] (Definition of direction)

[0044] In this specification, the direction from the rear end 22 of the rotating body 2 toward the front end 24 of the rotating body 2 is defined as "first direction DR1", and the direction opposite to the first direction DR1 is defined as "second direction DR2".

[0045] In this specification, the direction approaching the first axis AX1, which is the axis of rotation of the rotating body 2, is defined as "inward direction DR3" or "inward". Furthermore, the direction away from the first axis AX1, which is the axis of rotation of the rotating body 2, is defined as "outward direction DR4" or "outward".

[0046] The direction from the rear end 22 of the rotating body 2 toward the front end 24 of the rotating body 2 is, for example, downward or laterally. When the orientation of the machining head 10 can be changed, the direction from the rear end 22 of the rotating body 2 toward the front end 24 of the rotating body 2 varies depending on the orientation of the machining head 10. In this specification, regardless of the actual orientation of the machining head 10, the direction from the rear end 22 of the rotating body 2 toward the front end 24 of the rotating body is referred to as the "downward direction," and the direction from the front end 24 of the rotating body 2 toward the rear end 22 of the rotating body is referred to as the "upward direction." Furthermore, regardless of the actual orientation of the machining head 10, the surface on the first direction DR1 side is referred to as the "lower surface," and the surface on the second direction DR2 side is referred to as the "upper surface."

[0047] (First Implementation)

[0048] Reference Figures 1 to 6 The spindle lubrication device 1A of the machine tool in the first embodiment will be described. Figure 1 This is a schematic cross-sectional view of the spindle lubrication device 1A of the machine tool in the first embodiment. Figure 2 This is a schematic cross-sectional view of the spindle lubrication device 1A' of the machine tool in the comparative example. Figure 3 This is a schematic cross-sectional view of the spindle lubrication device 1A of a machine tool in a first variation of the first embodiment. Figure 4 This is a diagram schematically illustrating the measurement of the first and second recovery flow rates. Figure 5This diagram schematically illustrates the discharge of oil-containing fluid from the first recovery channel 71 and the second recovery channel 72 to the outside of the casing 4. Figure 6 This is a schematic cross-sectional view of the spindle lubrication device 1A of the machine tool in the first embodiment.

[0049] like Figure 1 As illustrated, the spindle lubrication device 1A of the machine tool in the first embodiment includes a rotating body 2 that holds the tool T, a plurality of bearings 3, a housing 4, a mixed fluid supply device 6, and a recovery device 7. The spindle lubrication device 1A of the machine tool may also include at least a controller 8 that controls the mixed fluid supply device 6.

[0050] exist Figure 1 In the described example, the rotating body 2 is the rotation axis 20. The rotating body 2 is capable of rotating about the first axis AX1. The rotating body 2 (more specifically, the rotation axis 20) has a rear end portion 22 and a front end portion 24 that holds the tool T. Additionally, sometimes a tool holder HD that holds the tool T is mounted on the front end portion 24. In this case, the tool T is held by the front end portion 24 by means of the tool holder HD. Therefore, in this specification, "front end portion 24 that holds the tool" includes both the front end portion 24 that directly holds the tool T and the front end portion 24 that holds the tool T by means of the tool holder HD. In other words, in this specification, the front end portion 24 can be configured to directly hold the tool T or to hold the tool T by means of the tool holder HD.

[0051] The housing 4 supports the rotating body 2 via multiple bearings 3, enabling it to rotate about the first axis AX1. Figure 1 In the example described, the housing 4 is composed of a component of multiple parts.

[0052] exist Figure 1 In the described example, the spindle lubrication device 1A includes a plurality of bearings 3, which include a first bearing 31a and a second bearing 36b. Figure 1 In the described example, the first bearing 31a is the front bearing 31 that supports the front end 24 of the rotating body 2. Furthermore, the second bearing 36b is the rear bearing 36 that supports the rear end 22 of the rotating body 2. Alternatively, the second bearing 36b could also be a bearing supporting the middle portion of the rotating body.

[0053] exist Figure 1 In the described example, the spindle lubrication device 1A of the machine tool includes a front bearing 31 supporting the front end 24 of the rotating body 2 and a rear bearing 36 supporting the rear end 22 of the rotating body 2. The front bearing 31 has at least one bearing including a first bearing 31a. The front bearing 31 may also have a first bearing 31a and a third bearing 31c. Figure 1In the described example, the rear bearing 36 has at least one bearing including the second bearing 36b. The rear bearing 36 may also have multiple bearings including the second bearing 36b.

[0054] The mixed fluid supply device 6 supplies a mixed fluid containing oil and air to multiple bearings 3. This mixed fluid is sometimes referred to as oil-gas. In the oil-gas mixture, the oil is transported by the air. In other words, in the oil-gas mixture, the air functions as the transport fluid for the oil. More specifically, by supplying oil-gas mixture to multiple bearings 3, a small amount of oil is continuously supplied to multiple bearings 3 by utilizing the flow of compressed air.

[0055] Recovery unit 7 recovers oil-containing fluids. Figure 1 In the described example, the recovery device 7 includes: multiple recovery channels (71, 72) disposed within the housing 4; multiple ejectors (75a, 75b) disposed outside the housing 4; and multiple flow control valves (76a, 76b). The recovery device 7 may also include multiple pipes (74a, 74b) fluidly connecting the multiple recovery channels (71, 72) to the multiple ejectors (75a, 75b). Alternatively, in the case where the multiple recovery channels (71, 72) and the multiple ejectors (75a, 75b) are directly connected, the multiple pipes (74a, 74b) can be omitted.

[0056] Multiple recovery channels (71, 72) are provided in the housing 4 to recover oil-containing fluid from multiple bearings 3. Figure 1 In the documented example, the multiple recycling channels (71, 72) include a first recycling channel 71 and a second recycling channel 72.

[0057] The first recovery channel 71 is provided in the housing 4 and mainly recovers the oil-containing fluid discharged from at least one bearing including the first bearing 31a. Hereinafter, the oil-containing fluid recovered via the first recovery channel 71 will be referred to as the "first oil-containing fluid". Figure 1 In the documented example, the first recovery channel 71 primarily recovers the first oil-containing fluid discharged from the front bearing 31. Figure 1 In the described example, all or most of the first recovery channel 71 is disposed within the housing 4. All or most of the first recovery channel 71 may also be formed by a through hole formed in the housing 4.

[0058] The second recovery channel 72 is provided in the housing 4 and primarily recovers oil-containing fluid discharged from at least one bearing including the second bearing 36b. Hereinafter, the oil-containing fluid recovered via the second recovery channel 72 will be referred to as the "second oil-containing fluid". Figure 1 In the documented example, the second recovery channel 72 primarily recovers the second oil-containing fluid discharged from the rear bearing 36. Figure 1In the described example, all or most of the second recovery channel 72 is disposed within the housing 4. All or most of the second recovery channel 72 may also be formed by a through-hole in the housing 4. Figure 1 In the recorded example, the second recovery channel 72 is a channel independent of the first recovery channel 71.

[0059] exist Figure 1 In the recorded example, multiple pipes (74a, 74b) include a first pipe 74a and a second pipe 74b.

[0060] The first conduit 74a fluidly connects the first recovery channel 71 to the first ejector 75a disposed outside the housing 4. Figure 1 In the described example, the first conduit 74a is entirely disposed outside the housing 4. Alternatively, a portion of the first conduit 74a may be disposed inside the housing 4, while the majority of the first conduit 74a may be disposed outside the housing 4. Figure 1 In the recorded example, the first injector 75a is an injector that corresponds one-to-one with the first recovery channel 71 via the first conduit 74a.

[0061] The second conduit 74b fluidly connects the second recovery channel 72 to the second ejector 75b disposed outside the housing 4. Figure 1 In the described example, the second pipe 74b is entirely disposed outside the housing 4. Alternatively, a portion of the second pipe 74b may be disposed inside the housing 4, while the majority of the second pipe 74b may be disposed outside the housing 4. Figure 1 In the example described, the second injector 75b is an injector that corresponds one-to-one with the second recovery channel 72 via the second conduit 74b.

[0062] Multiple injectors (75a, 75b) are configured outside the housing. Figure 1 In the documented example, the multiple injectors (75a, 75b) include a first injector 75a and a second injector 75b.

[0063] The first injector 75a generates a negative pressure using air supplied from the first air passage 77a, thereby drawing in the first oil-containing fluid from the first recovery passage 71. Hereinafter, the air supplied from the first air passage 77a to the first injector 75a will be referred to as "first air". Figure 1 In the described example, the first injector 75a uses the first air supplied from the first air passage 77a to generate negative pressure in the first pipe 74a, and draws the first oily fluid from the first recovery passage 71 through the first pipe 74a.

[0064] The second injector 75b generates a negative pressure using air supplied from the second air passage 77b, thereby drawing the second oil-containing fluid from the second recovery passage 72. Hereinafter, the air supplied from the second air passage 77b to the second injector 75b will be referred to as "second air". Figure 1 In the described example, the second injector 75b uses the second air supplied from the second air passage 77b to generate negative pressure in the second pipe 74b, and draws the second oil-containing fluid from the second recovery passage 72 through the second pipe 74b.

[0065] exist Figure 1 In the described example, multiple flow control valves (76a, 76b) include a first flow control valve 76a and a second flow control valve 76b. The first flow control valve 76a adjusts the flow rate of first air supplied from the first air passage 77a to the first injector 75a. The second flow control valve 76b adjusts the flow rate of second air supplied from the second air passage 77b to the second injector 75b.

[0066] exist Figure 1 In the described example, controller 8 sends a control command to mixing fluid supply device 6, which in turn supplies a mixture of oil and air (more specifically, oil-air mixture) to multiple bearings 3. Alternatively, controller 8 can also control recovery device 7. More specifically, controller 8 sends a control command to recovery device 7, which then recovers the oil-containing fluid.

[0067] The spindle lubrication device 1A' of the machine tool in the comparative example (see reference) Figure 2 In this configuration, multiple bearings 3 are fluidly connected to a negative pressure generating device 75' via pipes 74. Figure 2 In the documented example, the flow rate of the oil-containing fluid recovered from multiple bearings 3 cannot be adjusted for each bearing or each bearing group. Therefore, it is difficult to prevent poor lubrication in each of the multiple bearings. For example, in... Figure 2 In the described example, a scenario is envisioned where the lubrication of the second bearing 36b is adequate, but the recovery of the oil-containing fluid from the first bearing 31a is insufficient. In this case, oil may leak from the gap between the housing 4 and the rotating body 2. Therefore, to prevent this leakage, it is necessary to increase the suction capacity of the negative pressure generating device 75'. However, if the suction capacity of the negative pressure generating device 75' is increased, the recovery of the oil-containing fluid from the second bearing 36b becomes excessive, resulting in poor lubrication in the second bearing 36b.

[0068] exist Figure 2In the described example, we envision a situation where the number of bearings contained in the front bearing 31 differs from the number of bearings contained in the rear bearing 36. Alternatively or additionally, we envision a situation where the length of the first conduit 74a differs from the length of the second conduit 74b. In this case, if equal attractive forces are applied to the first conduit 74a and the second conduit 74b to prevent oil leakage from all bearings, it would be more likely to result in poorly lubricated bearings.

[0069] In this regard, the spindle lubrication device 1A of the machine tool in the first embodiment includes: a plurality of injectors, including a first injector 75a and a second injector 75b; and a plurality of flow control valves, including a first flow control valve 76a that adjusts the flow rate of a first air supplied to the first injector 75a and a second flow control valve 76b that adjusts the flow rate of a second air supplied to the second injector 75b.

[0070] Therefore, by adjusting the flow rates of the first air and the second air respectively, the flow rate of the recovered oil-containing fluid can be adjusted for each bearing or for each bearing assembly. As a result, poor lubrication can be avoided in each of the multiple bearings 3.

[0071] Furthermore, in the first embodiment, oil leakage is suppressed around the processing head 10 to prevent or suppress oil-induced pollution of the working environment. Therefore, the working environment is improved, and the environmental impact is reduced.

[0072] (arbitrarily added structure)

[0073] Next, refer to Figures 1 to 6 This explains any additional structures that can be used in the spindle lubrication device 1A of the machine tool in the first embodiment.

[0074] (Air Source AS)

[0075] exist Figure 1 In the described example, the spindle lubrication device 1A of the machine tool has at least one air source AS (e.g., an air compressor). The at least one air source AS supplies first air to a first air passage 77a and second air to a second air passage 77b. Figure 1 In the example described, the air source AS1 that supplies the first air to the first air passage 77a and the air source AS2 that supplies the second air to the second air passage 77b are the same air source. Alternatively, the air source AS2 that supplies the second air to the second air passage 77b may be a different air source from the air source AS1 that supplies the first air to the first air passage 77a.

[0076] (First airflow channel 77a and second airflow channel 77b)

[0077] exist Figure 1In the described example, the recovery device 7 has a first air passage 77a that supplies first air to the first injector 75a and a second air passage 77b that supplies second air to the second injector 75b. Figure 1 In the recorded example, a first flow control valve 76a is configured in the first air flow channel 77a, and a second flow control valve 76b is configured in the second air flow channel 77b.

[0078] (Main airflow channel 12)

[0079] exist Figure 1 In the described example, the spindle lubrication device 1A of the machine tool has a main air channel 12 that fluidly connects the air source AS to the first air channel 77a and the second air channel 77b. Figure 1 In the example described, the main airflow channel 12 is divided into multiple airflow channels, including the first airflow channel 77a and the second airflow channel 77b.

[0080] (On / off valve 13)

[0081] exist Figure 1 In the described example, the machine tool's spindle lubrication device 1A has an on / off valve 13 disposed between the air source AS and the first flow control valve 76a. When this on / off valve 13 is closed, air is not supplied to the first flow control valve 76a. Figure 1 In the example described, the on / off valve 13 is located in the main air flow channel 12. In this case, when the on / off valve 13 is in the open state, air is supplied to the first flow control valve 76a and the second flow control valve 76b, and when the on / off valve 13 is in the closed state, air is not supplied to the first flow control valve 76a and the second flow control valve 76b.

[0082] Alternatively, such as Figure 3 As illustrated, the spindle lubrication device 1A of the machine tool may also include a first on / off valve 13a disposed between the air source AS and the first flow control valve 76a, and a second on / off valve 13b disposed between the air source AS and the second flow control valve 76b. Figure 3 In the described example, the first on / off valve 13a is disposed in the first air flow channel 77a, and the second on / off valve 13b is disposed in the second air flow channel 77b. In this configuration, when the first on / off valve 13a is open, air is supplied to the first flow control valve 76a; when the first on / off valve 13a is closed, air is not supplied to the first flow control valve 76a. Similarly, when the second on / off valve 13b is open, air is supplied to the second flow control valve 76b; when the second on / off valve 13b is closed, air is not supplied to the second flow control valve 76b.

[0083] (Exhaust duct 78 and exhaust purifier 791)

[0084] exist Figure 1 In the described example, the recycling device 7 has an exhaust pipe 78 and a recycling container 792. Optionally, the recycling device 7 may also have an exhaust purifier 791.

[0085] Exhaust duct 78 receives exhaust gas (more specifically, oil-containing fluid) from multiple injectors (75a, 75b). Figure 1 In the described example, exhaust duct 78 fluidly connects multiple injectors (75a, 75b) to exhaust purifier 791. Exhaust duct 78 is, for example, composed of multiple pipes.

[0086] The recovery container 792 is fluidly connected to the exhaust pipe 78. Figure 1 In the described example, the recovery container 792 receives the liquid oil contained in the oily fluid from the exhaust pipe 78 via the exhaust purifier 791. Alternatively, the recovery container 792 may also receive the oily fluid directly from the exhaust pipe 78 without going through the exhaust purifier 791.

[0087] exist Figure 1 In the described example, exhaust purifier 791 receives oily fluid from multiple injectors (75a, 75b) via exhaust pipe 78. Furthermore, exhaust purifier 791 separates the oily fluid received from exhaust pipe 78 into liquid oil and air. The liquid oil separated from the oily fluid by exhaust purifier 791 is collected in recovery container 792.

[0088] exist Figure 1 In the described example, most of the oil used in the lubrication of the multiple bearings 3 is recycled to the recycling container 792 via the exhaust purifier 791. This prevents or inhibits oil contamination around the machining head 10. Consequently, the working environment is improved, and the environmental impact is reduced.

[0089] (Second Implementation)

[0090] Reference Figures 7 to 26 The spindle lubrication device 1B of the machine tool in the second embodiment will be described. Figure 7 This is a schematic cross-sectional view of the spindle lubrication device 1B of the machine tool in the second embodiment. Figure 8 This is a diagram schematically illustrating the measurement of the first and second recovery flow rates. Figure 9 This diagram schematically illustrates the discharge of oil-containing fluid from the first recovery channel 71 and the second recovery channel 72 to the outside of the casing 4. Figure 10 This is a schematic cross-sectional view of the spindle lubrication device 1B of the machine tool in the second embodiment. Figure 11 This is a schematic cross-sectional view showing a portion of the spindle lubrication device 1B of the machine tool in the second embodiment. Figure 12This is a diagram illustrating an example of the structure of the injector 75. Figure 13 This is a schematic cross-sectional view of the spindle lubrication device 1B of the machine tool in the first variation of the second embodiment. Figure 14 This is a schematic cross-sectional view showing a portion of the spindle lubrication device 1B of the machine tool in the first variation of the second embodiment. Figure 15 This is a diagram schematically illustrating the measurement of the first and second recovery flow rates. Figure 16 This diagram schematically illustrates the discharge of oil-containing fluid from the first recovery channel 71, the second recovery channel 72, and the third recovery channel 73 to the outside of the casing 4. Figure 17 This is a schematic cross-sectional view of the spindle lubrication device 1B of the machine tool in the first variation of the second embodiment. Figure 18 This is a schematic diagram showing a portion of the spindle lubrication device 1B of a machine tool in a first variation of the second embodiment. Figure 19 This is a schematic cross-sectional view illustrating an example of the processing head 10. Figures 20 to 22 , Figure 24 , Figure 25 This is a schematic cross-sectional view showing a portion of the spindle lubrication device 1B of the machine tool in the first variation of the second embodiment. Figure 23 This is a schematic cross-sectional view showing a portion of the spindle lubrication device 1B of a machine tool in a second variation of the second embodiment. Figure 26 This is a diagram used to illustrate the first annular groove V1 and the second annular groove V2.

[0091] In the second embodiment, the description focuses on the differences from the first embodiment. Furthermore, in the second embodiment, repetitions of matters already described in the first embodiment are omitted. Therefore, in the second embodiment, even without explicit explanation, matters already described in the first embodiment can be applied to the second embodiment. Conversely, all matters described in the second embodiment can be applied to the first embodiment.

[0092] like Figure 7As illustrated, the spindle lubrication device 1B of the machine tool in the second embodiment includes: (1) a rotating body 2 holding the tool T; (2) a plurality of bearings 3, including a first bearing 31a and a second bearing 36b; (3) a housing 4 supporting the rotating body 2 by means of the plurality of bearings 3 so that it can rotate about a first axis AX1; (4) a mixed fluid supply device 6 supplying a mixed fluid containing oil and air to the plurality of bearings 3; and (5) a recovery device 7 recovering the oil-containing fluid. Alternatively, the spindle lubrication device 1B of the machine tool may also include at least a controller 8 controlling the mixed fluid supply device 6. The recovery device 7 includes: (6A) a plurality of recovery channels (71, 72, 73) disposed in the housing 4 to recover the oil-containing fluid from the plurality of bearings 3; (6B) a plurality of ejectors (75a, 75b, 75c) disposed outside the housing 4; and (6C) a plurality of flow control valves (76a, 76b, 76c). Alternatively, the recovery device 7 may also include multiple pipes (74a, 74b, 74c) that fluidly connect multiple recovery channels (71, 72, 73) to multiple ejectors (75a, 75b, 75c).

[0093] exist Figure 7 In the described example, the multiple recovery channels (71, 72, 73) include: a first recovery channel 71, which primarily recovers a first oil-containing fluid discharged from at least one bearing including a first bearing 31a; and a second recovery channel 72, which primarily recovers a second oil-containing fluid discharged from at least one bearing including a second bearing 36b.

[0094] exist Figure 7 In the described example, the plurality of pipes (74a, 74b, 74c) include: a first pipe 74a that fluidly connects a first recovery channel 71 to a first ejector 75a; and a second pipe 74b that fluidly connects a second recovery channel 72 to a second ejector 75b.

[0095] exist Figure 7 In the described example, the plurality of injectors (75a, 75b, 75c) include: a first injector 75a that uses first air supplied from a first air passage 77a to generate negative pressure in a first conduit 74a, and draws a first oil-containing fluid from a first recovery passage 71 via the first conduit 74a; and a second injector 75b that uses second air supplied from a second air passage 77b to generate negative pressure in a second conduit 74b, and draws a second oil-containing fluid from a second recovery passage 72 via the second conduit 74b.

[0096] exist Figure 7In the described example, the plurality of flow control valves (76a, 76b, 76c) include: a first flow control valve 76a, which adjusts the flow rate of first air supplied from a first air passage 77a to a first injector 75a; and a second flow control valve 76b, which adjusts the flow rate of second air supplied from a second air passage 77b to a second injector 75b.

[0097] Based on the above, the spindle lubrication device 1B of the machine tool in the second embodiment achieves the same effect as the spindle lubrication device 1A of the machine tool in the first embodiment.

[0098] (arbitrarily added structure)

[0099] Next, refer to Figures 1 to 26 This describes any additional structure that can be used in the spindle lubrication device 1B of the machine tool in the second embodiment (or the spindle lubrication device 1A of the machine tool in the first embodiment).

[0100] (Setting of the first recovery flow rate, the first discharge flow rate, and the opening degree of the first flow control valve 76a)

[0101] exist Figure 4 , Figure 5 , Figure 8 , Figure 9 In the middle, a first flow rate of mixed fluid is supplied from the mixed fluid supply device 6 to multiple bearings 3 (refer to arrow AR1).

[0102] exist Figure 4 or Figure 8 The diagram illustrates the fluid connections between multiple pipes (74a, 74b, ...) and multiple recovery channels (71, 72, ...). More specifically, in... Figure 4 and Figure 8 In the described example, the first conduit 74a is fluidly connected to the first recovery channel 71, and the second conduit 74b is fluidly connected to the second recovery channel 72. Furthermore, in Figure 8 In the documented example, the third conduit 74c is fluidly connected to the third recovery channel 73.

[0103] exist Figure 5 or Figure 9 The diagram illustrates the fluid separation process from multiple recovery channels (71, 72, ...) via multiple pipes (74a, 74b, ...). More specifically, in... Figure 5 and Figure 9 In the documented example, the first conduit 74a separates fluid from the first recovery channel 71, and the second conduit 74b separates fluid from the second recovery channel 72. Furthermore, in... Figure 9 In the documented example, the third conduit 74c separates the fluid from the third recovery channel 73.

[0104] like Figure 4 or Figure 8 As illustrated, under the first condition CD1, where multiple pipes (74a, 74b, ...) are fluidly connected to multiple recovery channels (71, 72, ...) respectively, and a first flow rate of mixed fluid is supplied from the mixed fluid supply device 6 to multiple bearings 3, the flow rate of the first oil-containing fluid flowing in the first pipe 74a is defined as the first recovery flow rate (refer to...). Figure 4 , Figure 8 (Arrow AR2 in the diagram). The first recovery flow rate is derived, for example, by measurement. Figure 4 or Figure 8 In the described example, the spindle lubrication device 1 of the machine tool has a first flow meter 11a disposed in the first pipe 74a. In this case, the first flow meter 11a can be used to measure the first recovery flow rate. Alternatively, the first flow meter 11a can be removed from the first pipe 74a after the first recovery flow rate is measured. Alternatively, the first flow meter 11a can remain installed in the first pipe 74a after the first recovery flow rate is measured.

[0105] like Figure 5 or Figure 9 As illustrated, under the second condition CD2, which differs from the first condition CD1 described above, fluid will be separated from the first recovery channel 71 by only multiple pipes (74a, 74b, ...) from multiple recovery channels (71, 72, ...). Figure 5 or Figure 9 In the recorded example, the flow rate of the first oil-containing fluid discharged from the first recovery channel 71 (outside the casing 4) is defined as the first discharge flow rate (refer to...). Figure 5 , Figure 9 (Arrow AR4 in the diagram). The first discharge flow rate can be derived by measurement or by simulation. For example, the first oily fluid ejected from the first recovery channel 71 to the outside of the housing 4 can be recovered into the bag, and the first discharge flow rate can be derived by dividing the volume of the recovered first oily fluid by the recovery time. Alternatively, the first discharge flow rate can be measured using a spindle lubrication device of the same type as the spindle lubrication device 1 described above, except that it does not have the recovery device 7.

[0106] The first condition CD1 described above may also include the condition of maintaining the rotation angle of the rotating body 2 relative to the housing 4 about the first axis AX1. In this case, the second condition CD2 described above includes the condition of maintaining the rotation angle of the rotating body 2 relative to the housing 4 about the first axis AX1. Alternatively, the first condition CD1 may also include the condition that the rotating body 2 rotates relative to the housing 4 about the first axis AX1 at a predetermined speed (e.g., 20,000 rpm or the maximum speed in the design specifications of the spindle lubrication device). In this case, the second condition CD2 described above includes the condition that the rotating body 2 rotates relative to the housing 4 about the first axis AX1 at this predetermined speed (e.g., 20,000 rpm or the maximum speed in the design specifications of the spindle lubrication device).

[0107] Under the first condition CD1, the flow rate (i.e., the first flow rate) of the mixed fluid supplied from the mixed fluid supply device 6 to the multiple bearings 3 is equal to the flow rate (i.e., the first flow rate) of the mixed fluid supplied from the mixed fluid supply device 6 to the multiple bearings 3 under the second condition CD2. It is envisioned that when the spindle lubrication device 1 is operating, the upper limit and lower limit of the flow rate of the mixed fluid supplied from the mixed fluid supply device 6 to the multiple bearings 3 are predetermined. In this case, under both the first condition CD1 and the second condition CD2, the value of the first flow rate of the mixed fluid supplied from the mixed fluid supply device 6 to the multiple bearings 3 is set to any value within the range of above the lower limit and below the upper limit. Under both the first condition CD1 and the second condition CD2, the value of the first flow rate of the mixed fluid supplied from the mixed fluid supply device 6 to the multiple bearings 3 can be set to the upper limit, the lower limit, or a value smaller than the upper limit and larger than the lower limit.

[0108] exist Figure 6 or Figure 10 In the described example, the opening degree of the first flow control valve 76a is set such that the first recovery flow rate is within a range of more than 1 and less than 1.5 times the first discharge flow rate (more preferably, within a range of more than 1 and less than 1.2 times the first discharge flow rate). The opening degree of the first flow control valve 76a can be set manually or by the controller 8.

[0109] When manually setting the opening of the first flow control valve 76a, the operator adjusts the opening of the first flow control valve 76a while referring to the value of the first recovery flow indicated by the first flow meter 11a. In this way, the operator manually sets the opening of the first flow control valve 76a so that the first recovery flow is within a range of more than 1 and less than 1.5 times the first discharge flow. When setting the opening of the first flow control valve 76a via the controller 8, the controller 8 can also automatically adjust the opening of the first flow control valve 76a so that the value of the first recovery flow indicated by the first flow meter 11a is within a range of more than 1 and less than 1.5 times the first discharge flow. Furthermore, the first flow meter 11a can be removed from the first pipe 74a after adjusting the first recovery flow, or it can remain installed in the first pipe 74a.

[0110] By ensuring that the first recovery flow rate is more than one times the first discharge flow rate, insufficient recovery of the first oil-containing fluid is prevented. This prevents oil leakage from the gap between the rotating body 2 and the housing 4 to the spindle lubrication device 1 of the machine tool. Furthermore, by ensuring that the first recovery flow rate is less than 1.5 times the first discharge flow rate, excessive recovery of the first oil-containing fluid is prevented. This prevents poor lubrication in at least one bearing, including the first bearing 31a.

[0111] (Setting of the second recovery flow rate, the second discharge flow rate, and the opening degree of the second flow control valve 76b)

[0112] like Figure 4 or Figure 8 As illustrated, under the first condition CD1 described above, the flow rate of the second oil-containing fluid flowing in the second conduit 74b is defined as the second recovery flow rate (refer to...). Figure 4 , Figure 8 (Arrow AR3 in the diagram). The second recovery flow rate is derived, for example, by measurement. Figure 4 or Figure 8 In the described example, the machine tool spindle lubrication device 1 has a second flow meter 11b disposed in the second pipe 74b. In this case, the second flow meter 11b can be used to measure the second recovery flow rate. Alternatively, the second flow meter 11b can be removed from the second pipe 74b after the second recovery flow rate is measured. Alternatively, the second flow meter 11b can remain installed in the second pipe 74b after the second recovery flow rate is measured.

[0113] like Figure 5 or Figure 9 As illustrated, under the second condition CD2 described above, the flow will be directed from the second recovery channel 72 to the outside of the second recovery channel 72 (in... Figure 5 or Figure 9In the recorded example, the flow rate of the second oil-containing fluid discharged from the second recovery channel 72 (outside the casing 4) is defined as the second discharge flow rate (refer to...). Figure 5 , Figure 9 (Arrow AR5 in the diagram). The second discharge flow rate can be derived by measurement or by simulation. For example, the second oily fluid ejected from the second recovery channel 72 to the outside of the housing 4 can be recovered into the bag, and the second discharge flow rate can be derived by dividing the volume of the recovered second oily fluid by the recovery time. Alternatively, the second discharge flow rate can be measured using a spindle lubrication device of the same type as the spindle lubrication device 1 described above, except that it does not have the recovery device 7.

[0114] exist Figure 6 or Figure 10 In the described example, the opening degree of the second flow control valve 76b is set such that the second recovery flow rate is within a range of more than 1 and less than 1.5 times the second discharge flow rate (more preferably, within a range of more than 1 and less than 1.2 times the second discharge flow rate). The opening degree of the second flow control valve 76b can be set manually or by the controller 8.

[0115] When manually setting the opening of the second flow control valve 76b, the operator adjusts the opening of the second flow control valve 76b while referring to the value of the second recovery flow indicated by the second flow meter 11b. In this way, the operator manually sets the opening of the second flow control valve 76b so that the second recovery flow is within a range of more than 1 and less than 1.5 times the second discharge flow. When setting the opening of the second flow control valve 76b via the controller 8, the controller 8 can also automatically adjust the opening of the second flow control valve 76b so that the value of the second recovery flow indicated by the second flow meter 11b is within a range of more than 1 and less than 1.5 times the second discharge flow. Furthermore, the second flow meter 11b can be removed from the second pipe 74b after adjusting the second recovery flow, or it can remain installed in the second pipe 74b.

[0116] By ensuring that the second recovery flow rate is more than one time the second discharge flow rate, insufficient recovery of the second oil-containing fluid is prevented. This prevents oil leakage from the gap between the rotating body 2 and the housing 4 to the machining head 10. Furthermore, by ensuring that the second recovery flow rate is less than 1.5 times the second discharge flow rate, excessive recovery of the second oil-containing fluid is prevented. This prevents poor lubrication in at least one bearing including the second bearing 36b.

[0117] For example, when the lengths of multiple pipes (74a, 74b, ...) are long, or when the length of the exhaust pipe 78 is long, the pressure loss of the oil-containing fluid flowing in the pipes increases. In this case, it is necessary to increase the suction force of the multiple injectors (75a, 75b, ...). However, if the suction force of the multiple injectors (75a, 75b, ...) is increased, poor lubrication of the bearings is likely to occur. Furthermore, when the number of bearings in the front bearing 31 differs from the number of bearings in the rear bearing 36, or when the lengths of the first pipe 74a and the second pipe 74b differ, lubrication imbalances can easily occur among the multiple bearings. To address this, if the opening degrees of the first flow control valve 76a and the second flow control valve 76b are appropriately set as described above, poor lubrication will not occur in the multiple bearings individually.

[0118] (Multiple bearings 3)

[0119] The plurality of bearings 3 includes a first bearing 31a and a second bearing 36b. Alternatively, the plurality of bearings 3 may also include a third bearing 31c. Figure 6 , Figure 10 In the described example, the third bearing 31c is positioned between the first bearing 31a and the second bearing 36b along the direction of the first axis AX1. The third bearing 31c is, for example, a ball bearing.

[0120] The first bearing 31a constitutes at least a portion of the front bearing 31 supporting the front end portion 24 of the rotating body 2. The first bearing 31a is, for example, a ball bearing. Figure 6 , Figure 10 In the described example, the first bearing 31a is the bearing located on the side furthest from the first direction DR1 (in other words, the foremost side) among the multiple bearings 3 supporting the rotating body 2. The front bearing 31 of the front end 24 supporting the rotating body 2 may also comprise multiple bearings. Figure 6 , Figure 10 In the example described, the front bearing 31 includes a first bearing 31a and a third bearing 31c.

[0121] exist Figure 11 In the described example, the first bearing 31a has an inner ring 32a, an outer ring 33a, and a rolling element 34a disposed between the inner ring 32a and the outer ring 33a. Furthermore, the third bearing 31c has an inner ring 32c, an outer ring 33c, and a rolling element 34c disposed between the inner ring 32c and the outer ring 33c.

[0122] exist Figure 6 , Figure 10 In the described example, the second bearing 36b constitutes at least a portion of the rear bearing 36 supporting the rear end 22 of the rotating body 2. The second bearing 36b is, for example, a roller bearing.

[0123] (Recycling device 7)

[0124] exist Figure 10 In the recorded example, the recycling device 7 includes: (1) a plurality of recycling channels, including a first recycling channel 71, a second recycling channel 72 and a third recycling channel 73; (2) a plurality of pipes, including a first pipe 74a, a second pipe 74b and a third pipe 74c; (3) a plurality of injectors, including a first injector 75a, a second injector 75b and a third injector 75c; and (4) a plurality of flow control valves, including a first flow control valve 76a, a second flow control valve 76b and a third flow control valve 76c.

[0125] The first recovery channel 71, the second recovery channel 72, the first pipe 74a, the second pipe 74b, the first injector 75a, the second injector 75b, the first flow control valve 76a, and the second flow control valve 76b have been described in the first embodiment, so a repeated description of their structure is omitted.

[0126] The third recovery channel 73 is located in the housing 4. Figure 11 In the described example, all or most of the third recovery channel 73 is disposed within the housing 4. All or most of the third recovery channel 73 may also be formed by a through hole formed in the housing 4.

[0127] The third recovery channel 73 recovers oil-containing fluid that was not recovered by the first recovery channel 71 but passed through the first bearing 31a. Hereinafter, the oil-containing fluid recovered via the third recovery channel 73 will be referred to as the "third oil-containing fluid". Figure 10 In the recorded example, the third recovery channel 73 is a channel independent of the first recovery channel 71 and the second recovery channel 72.

[0128] like Figure 10 As illustrated, the third conduit 74c fluidly connects the third recovery channel 73 to the third ejector 75c disposed outside the housing 4. Figure 10 In the example described, the third conduit 74c is entirely disposed outside the housing 4. Alternatively, a portion of the third conduit 74c may be disposed inside the housing 4, while the majority of the third conduit 74c may be disposed outside the housing 4.

[0129] The third injector 75c generates negative pressure using air supplied from the third air passage 77c, thereby drawing in the third oil-containing fluid from the third recovery passage 73. Hereinafter, the air supplied from the third air passage 77c to the third injector 75c will be referred to as "third air". Figure 10In the described example, the third injector 75c utilizes third air supplied from the third air passage 77c to generate negative pressure in the third conduit 74c, drawing in the third oil-containing fluid from the third recovery passage 73 via the third conduit 74c. Figure 10 In the recorded example, the third injector 75c is an injector that corresponds one-to-one with the third recovery channel 73 via the third conduit 74c.

[0130] The third flow control valve 76c adjusts the flow rate of the third air supplied from the third air passage 77c to the third injector 75c. The opening degree of the third flow control valve 76c can be set manually or by the controller 8.

[0131] exist Figure 11 In the described example, the spindle lubrication device 1 of the machine tool has a third recovery channel 73, which recovers a third oil-containing fluid that was not recovered by the first recovery channel 71 but passed through the first bearing 31a. Therefore, leakage of oil that has passed through the first bearing 31a from the gap between the rotating body 2 and the front end 46 of the housing 4 is effectively suppressed.

[0132] For example, consider a situation where oil is not desired to adhere to a workpiece machined by tool T. More specifically, consider a situation where a workpiece made of carbonaceous material is being machined, as oil adhesion would cause adverse effects. In this case, an embodiment including a third recovery channel 73 is useful.

[0133] Furthermore, when machining resin materials using a cutting tool T, dry machining is sometimes employed. In embodiments including a third recovery channel 73, oil leakage from the gap between the rotating body 2 and the front end 46 of the housing 4 is suppressed, effectively preventing oil from adhering to the workpiece (e.g., resin materials). Therefore, embodiments including a third recovery channel 73 are also useful when dry machining is employed.

[0134] In embodiments including the third recovery channel 73, oil leakage from the gap between the rotating body 2 and the front end 46 of the housing 4 is prevented. Therefore, in cases where a cooling medium is used during workpiece machining (in other words, in cases where machining is not dry), oil mixing with the cooling medium is prevented. This reduces the environmental impact.

[0135] exist Figure 10 In the described example, the recycling device 7 includes an exhaust pipe 78, an exhaust purifier 791, and a recycling container 792. Figure 10 In the documented example, exhaust duct 78 fluidly connects the first injector 75a, the second injector 75b, and the third injector 75c to the exhaust purifier 791.

[0136] Exhaust purifier 791 receives oily fluid from multiple injectors (75a, 75b, 75c) via exhaust pipe 78. Furthermore, exhaust purifier 791 separates the oily fluid received from exhaust pipe 78 into liquid oil and air. The liquid oil separated from the oily fluid by exhaust purifier 791 is recycled to recovery container 792.

[0137] (Structure of injector 75)

[0138] Figure 12 An example of the structure of the ejector 75 is shown. The ejector 75 has an inlet port 751, an outlet port 752, and a vacuum port 753. If compressed air is supplied to the inlet port 751 of the ejector 75, the target fluid is drawn into the ejector 75 through the vacuum port 753. The compressed air and the target fluid are discharged from the ejector 75 through the outlet port 752. If the flow rate of the compressed air supplied to the inlet port 751 increases, the flow rate of the target fluid drawn into the ejector 75 increases. On the other hand, if the flow rate of the compressed air supplied to the inlet port 751 decreases, the flow rate of the target fluid drawn into the ejector 75 decreases.

[0139] Regarding the first injector 75a, the aforementioned first airflow channel 77a is connected to the inlet port 751a, the aforementioned exhaust pipe 78 is connected to the outlet port 752a, and the aforementioned first pipe 74a is connected to the vacuum port 753a. Regarding the second injector 75b, the aforementioned second airflow channel 77b is connected to the inlet port 751b, the aforementioned exhaust pipe 78 is connected to the outlet port 752b, and the aforementioned second pipe 74b is connected to the vacuum port 753b. Regarding the third injector 75c, the aforementioned third airflow channel 77c is connected to the inlet port 751c, the aforementioned exhaust pipe 78 is connected to the outlet port 752c, and the aforementioned third pipe 74c is connected to the vacuum port 753c.

[0140] (Air supply device 9)

[0141] like Figure 13 As illustrated, the spindle lubrication device 1 of the machine tool may also include an air supply device 9. The air supply device 9 has: an air source AS (e.g., an air compressor) disposed outside the housing 4; an air supply passage 93 disposed in the housing 4; an air supply pipe 91 connecting the air source AS to the air supply passage 93; and a fourth flow control valve 96.

[0142] exist Figure 13In the described example, the air supply pipe 91 is disposed outside the housing 4. The air supply pipe 91 supplies air to the air supply channel 93. Hereinafter, the air supplied from the air supply pipe 91 to the air supply channel 93 will be referred to as "fourth air." The fourth flow control valve 96 adjusts the flow rate of the fourth air supplied from the air supply pipe 91 to the air supply channel 93. Figure 13 In the example described, the fourth flow control valve 96 is located on the air supply pipe 91. The opening degree of the fourth flow control valve 96 can be set manually or by the controller 8.

[0143] exist Figure 14 In the described example, an air injection port OP1 is formed between the rotating body 2 (more specifically, the rotating shaft 20) and the front end portion 46 of the housing 4. Furthermore, an outlet 49 is formed in the housing 4, which ejects a fourth air received from the air supply channel 93 into the gap G between the rotating body 2 and the housing 4. The fourth air ejected from the outlet 49 forms both a first flow from the gap G toward the third recovery channel 73 and a second flow from the gap G toward the air injection port OP1.

[0144] The fourth type of air ejected from the air jet port OP1 prevents foreign objects such as chips from entering the housing 4 through the gap G. More specifically, in Figure 13 In the described example, the fourth air injected from the air jet OP1 forms an air curtain AC around the tool T or tool holder HD. This air curtain AC prevents foreign objects such as chips from entering the housing 4 through the gap G.

[0145] exist Figure 14 In the described example, the first flow from gap G toward the third recovery channel 73 (more specifically, the fourth air flow from gap G toward the third recovery channel 73) pushes the oil E1 entering gap G back toward the third recovery channel 73. Therefore, oil leakage from the gap between the rotating body 2 and the front end 46 of the housing 4 is more effectively suppressed.

[0146] Compared to the other recovery channels (71, 72), the third recovery channel 73 contains a relatively larger amount of fourth air (in other words, fourth air ejected from the nozzle 49). Furthermore, in Figure 13 In the documented example, compared to the other pipes (74a, 74b), the third pipe 74c contains a relatively larger amount of fourth air (in other words, the fourth air ejected from the nozzle 49). In this case, if equal attractive forces are applied to the first pipe 74a, the second pipe 74b, and the third pipe 74c, an imbalance in oil recovery can easily occur among the multiple bearings. To address this, in Figure 13In the described example, the attractive forces acting on the first conduit 74a, the second conduit 74b, and the third conduit 74c can be adjusted independently. Therefore, by individually and appropriately setting these attractive forces, it is possible to prevent poor lubrication in multiple bearings.

[0147] (Setting the opening degree of the first flow control valve 76a and the second flow control valve 76b)

[0148] exist Figure 15 , Figure 16 In this context, a first flow rate of mixed fluid is supplied from the mixed fluid supply device 6 to multiple bearings 3 (refer to arrow AR1). Figure 15 , Figure 16 In this configuration, a fourth air with a second flow rate is supplied to the air supply channel 93 (refer to arrow AR7). Furthermore, in... Figure 15 , Figure 16 In the middle, air is injected from the air injection port OP1 (refer to arrow AR6).

[0149] exist Figure 15 The diagram illustrates the fluid connections between multiple pipes (74a, 74b, 74c) and multiple recovery channels (71, 72, 73). More specifically, in... Figure 15 In the recorded example, the first pipe 74a is fluidly connected to the first recovery channel 71, the second pipe 74b is fluidly connected to the second recovery channel 72, and the third pipe 74c is fluidly connected to the third recovery channel 73.

[0150] exist Figure 16 The diagram illustrates the fluid separation process from multiple recovery channels (71, 72, 73) via multiple pipes (74a, 74b, 74c). More specifically, in... Figure 16 In the recorded example, the first pipe 74a separates fluid from the first recovery channel 71, the second pipe 74b separates fluid from the second recovery channel 72, and the third pipe 74c separates fluid from the third recovery channel 73.

[0151] like Figure 15 As illustrated, under the third condition CD3, in which multiple pipes (74a, 74b, 74c) are fluidly connected to multiple recovery channels (71, 72, 73) respectively, a first flow rate of mixed fluid is supplied from the mixed fluid supply device 6 to multiple bearings 3, and a second flow rate of fourth air is supplied to the air supply channel 93, the flow rate of the first oil-containing fluid flowing in the first pipe 74a is defined as the first recovery flow rate (refer to...). Figure 15 (Arrow AR2 in the text). Furthermore, under the third condition CD3 described above, the flow rate of the second oil-containing fluid flowing in the second conduit 74b is defined as the second recovery flow rate (refer to...). Figure 15(See arrow AR3 in the diagram). Furthermore, the methods for measuring the first and second recovery flow rates have already been described, therefore a repetition of these methods is omitted.

[0152] like Figure 16 As illustrated, under the fourth condition CD4, which differs from the third condition CD3 described above in that only multiple pipes (74a, 74b, 74c) separate fluid from multiple recovery channels (71, 72, 73), the flow rate of the first oil-containing fluid discharged from the first recovery channel 71 to outside the first recovery channel 71 (e.g., outside the casing 4) is defined as the first discharge flow rate (refer to...). Figure 16 (Arrow AR4 in the text). Furthermore, under the fourth condition CD4 described above, the flow rate of the second oil-containing fluid discharged from the second recovery channel 72 to outside the second recovery channel 72 (e.g., outside the casing 4) is defined as the second discharge flow rate (refer to...). Figure 16 (See arrow AR5 in the diagram). Furthermore, the methods (or methods for deriving) the first and second recovery flow rates have already been described, therefore, a repetition of these methods (or methods for deriving) is omitted.

[0153] The third condition CD3 described above may also include the condition of maintaining the rotation angle of the rotating body 2 relative to the housing 4 about the first axis AX1. In this case, the fourth condition CD4 described above includes the condition of maintaining the rotation angle of the rotating body 2 relative to the housing 4 about the first axis AX1. Alternatively, the third condition CD3 described above may also include the condition that the rotating body 2 rotates relative to the housing 4 about the first axis AX1 at a predetermined speed (e.g., 20,000 rpm or the maximum speed in the design specifications of the spindle lubrication device). In this case, the fourth condition CD4 described above includes the condition that the rotating body 2 rotates relative to the housing 4 about the first axis AX1 at this predetermined speed (e.g., 20,000 rpm or the maximum speed in the design specifications of the spindle lubrication device).

[0154] Under the third condition CD3, the flow rate (i.e., the first flow rate) of the mixed fluid supplied from the mixed fluid supply device 6 to the multiple bearings 3 is equal to the flow rate (i.e., the first flow rate) of the mixed fluid supplied from the mixed fluid supply device 6 to the multiple bearings 3 under the fourth condition CD4. It is envisioned that when the spindle lubrication device 1 is operating, the upper limit and lower limit of the flow rate of the mixed fluid supplied from the mixed fluid supply device 6 to the multiple bearings 3 are predetermined. In this case, under both the third condition CD3 and the fourth condition CD4, the value of the first flow rate of the mixed fluid supplied from the mixed fluid supply device 6 to the multiple bearings 3 is set to any value within the range of above the lower limit and below the upper limit. Under both the third condition CD3 and the fourth condition CD4, the value of the first flow rate of the mixed fluid supplied from the mixed fluid supply device 6 to the multiple bearings 3 can be set to the upper limit, the lower limit, or a value smaller than the upper limit and larger than the lower limit.

[0155] Under the third condition CD3, the flow rate of the fourth air supplied to the air supply channel 93 (i.e., the second flow rate) is equal to the flow rate of the fourth air supplied to the air supply channel 93 (i.e., the second flow rate) under the fourth condition CD4. Under the fourth condition CD4, the flow rate of the air ejected from the air injection port OP1 is defined as the "third flow rate". Under the fourth condition CD4 (refer to...) Figure 16 Preferably, the flow rate of the fourth air supplied to the air supply channel 93 is set in such a way that the third flow rate becomes the flow rate required to form an air curtain (e.g., the flow rate of the design lower limit for forming an air curtain).

[0156] exist Figure 17 In the described example, the opening of the first flow control valve 76a is set such that the first recovery flow rate is within a range of more than 1 and less than 1.5 times the first discharge flow rate (more preferably, within a range of more than 1 and less than 1.2 times the first discharge flow rate). The opening of the first flow control valve 76a can be set manually or by the controller 8. Furthermore, the opening of the second flow control valve 76b is set such that the second recovery flow rate is within a range of more than 1 and less than 1.5 times the second discharge flow rate (more preferably, within a range of more than 1 and less than 1.2 times the second discharge flow rate). The opening of the second flow control valve 76b can be set manually or by the controller 8.

[0157] In addition, the third condition CD3 is a form of the first condition CD1, and the fourth condition CD4 is a form of the second condition CD2.

[0158] (Settings for the opening of the third flow control valve 76c and the fourth flow control valve 96)

[0159] exist Figure 17 The text indicates the state after setting the opening degree of the first flow control valve 76a and the second flow control valve 76b. Figure 17 In the recorded example, the opening degree of the third flow control valve 76c and the opening degree of the fourth flow control valve 96 are set to allow the flow from the nozzle 49 (see reference) to... Figure 14 The flow rate of the fourth air ejected is greater than that from the air injection port OP1 (refer to...). Figure 14 The flow rate of the ejected air. Figure 14 In the recorded example, by setting the flow rate of the fourth air ejected from the nozzle 49 to be greater than the flow rate of the air ejected from the air nozzle OP1, oil E1 that is ejected from the air nozzle OP1 along with the air ejected from the air nozzle OP1 is prevented or suppressed.

[0160] For example, if the opening degree of the third flow control valve 76c is small, the recovery of the third oily fluid from the third recovery channel 73 becomes insufficient. Figure 14 In the described example, oil E1 sometimes flows from the gap between the housing 4 and the rotating body 2 toward the air injection port OP1. More specifically, the flow rate of air injected through the air injection port OP1 is greater than the flow rate of the fourth air ejected from the nozzle 49, thus sometimes oil E1 is injected from the air injection port OP1 along with the air injected from the air injection port OP1. Therefore, it is preferable to appropriately set the relationship between the opening degree of the third flow control valve 76c and the opening degree of the fourth flow control valve 96 so that the flow rate of air injected through the air injection port OP1 is not greater than the flow rate of the fourth air ejected from the nozzle 49.

[0161] exist Figure 17 In the described example, the opening degree of the third flow control valve 76c and the fourth flow control valve 96 are preferably set such that the flow rate of the air injected from the air injection port OP1 is greater than or equal to the aforementioned third flow rate (more specifically, greater than or equal to the design lower limit value for forming an air curtain). With this setting, an air curtain is appropriately formed to prevent foreign objects from entering the processing head 10 from the front end of the processing head 10.

[0162] exist Figure 17 In the recorded example, by recovering a portion of the fourth air ejected from the nozzle 49 via the third recovery channel 73, the flow rate of air ejected from the air injection port OP1 is reduced. Therefore, in Figure 17In the described example, by making the opening of the fourth flow control valve 96 sufficiently large, a portion of the fourth air ejected from the nozzle 49 is recovered via the third recovery channel 73, thereby enabling the flow rate of air ejected from the air injection port OP1 to be greater than the aforementioned third flow rate. By recovering a portion of the fourth air ejected from the nozzle 49 via the third recovery channel 73, oil E1 (refer to [reference needed]) is prevented. Figure 14 The air jet is directed toward the air jet port OP1. Furthermore, by jetting air at a flow rate of 3 or higher from the air jet port OP1, foreign objects are prevented from entering the machining head 10 from the front end of the machining head 10.

[0163] exist Figure 17 In the described example, the opening degrees of the third flow control valve 76c and the fourth flow control valve 96 can also be set such that the flow rate of air injected from the air injection port OP1 is more than 1 and less than 1.5 times the aforementioned third flow rate (more specifically, the flow rate used to form the lower limit of the design value of the air curtain). By ensuring that the flow rate of air injected from the air injection port OP1 is less than 1.5 times the aforementioned third flow rate, the amount of air injected from the air injection port OP1 will not become excessive.

[0164] (Mixed fluid supply device 6)

[0165] exist Figure 17 In the described example, the mixed fluid supply device 6 has an air source AT (e.g., an air compressor), an oil tank 61, a pump 62, a second air supply pipe 63, a mixer 64, a supply channel 66, and a mixed fluid supply pipe 68 connecting the mixer 64 and the supply channel 66.

[0166] Air source AT supplies air to mixer 64 via second air supply pipe 63. Hereinafter, the air supplied to mixer 64 via second air supply pipe 63 will be referred to as "fifth air". Pump 62 supplies oil from oil tank 61 to mixer 64. Mixer 64 mixes the fifth air received from air source AT via second air supply pipe 63 and the oil received from oil tank 61 to form a mixed fluid containing oil and air. Furthermore, mixer 64 delivers this mixed fluid to supply channel 66 via mixed fluid supply pipe 68.

[0167] exist Figure 17 In the described example, the mixed fluid supply pipe 68 is disposed outside the housing 4, and the supply channel 66 is disposed inside the housing 4. The supply channel 66 supplies a mixed fluid (more specifically, oil-air mixture) containing oil and air to the plurality of bearings 3. Figure 17 In the recorded example, the supply channel 66 supplies a mixed fluid containing oil and air to the first bearing 31a, the second bearing 36b and the third bearing 31c.

[0168] exist Figure 17In the described example, the air source AT supplying air to the mixer 64 is the same air source as the air source AS supplying air to the multiple injectors (75a, 75b, 75c). By sharing the air source AT supplying air to the mixer 64 and the air source AS supplying air to the multiple injectors (75a, 75b, 75c), space saving is achieved. Furthermore, manufacturing costs and energy consumption are reduced. Alternatively, the air source AT supplying air to the mixer 64 can be a different air source from the air source AS supplying air to the multiple injectors (75a, 75b, 75c).

[0169] The mixing fluid supply device 6 may also have a fifth flow control valve 67, which adjusts the flow rate of air supplied from the second air supply pipe 63 to the mixer 64. Figure 17 In the example described, the fifth flow control valve 67 is located in the second air supply pipe 63. The opening degree of the fifth flow control valve 67 can be set manually or by the controller 8.

[0170] (First airflow channel 77a, second airflow channel 77b and third airflow channel 77c)

[0171] The first airflow channel 77a and the second airflow channel 77b have already been described in the first embodiment, therefore a repeated description of these channels is omitted. Figure 17 In the described example, the recovery device 7 has a third air passage 77c for supplying third air to the third injector 75c. Figure 17 In the example described, a third flow control valve 76c is configured in the third air passage 77c.

[0172] (Main airflow channel 12)

[0173] exist Figure 17 In the described example, the spindle lubrication device 1 of the machine tool has a main air channel 12 that connects a first air channel 77a, a second air channel 77b, and a third air channel 77c to an air source AS. Figure 17 In the example described, the main airflow channel 12 is divided into multiple airflow channels including a first airflow channel 77a, a second airflow channel 77b, and a third airflow channel 77c.

[0174] The main airflow channel 12 can also be connected to an air supply pipe 91 that supplies air to the air supply channel 93 provided in the housing 4. In addition, the main airflow channel 12 can also be connected to a second air supply pipe 63 that supplies fifth air to the mixer 64.

[0175] (On / off valve 13)

[0176] exist Figure 18In the example described, the spindle lubrication device 1 of the machine tool has multiple on / off valves 13 disposed between the air source AS and multiple flow control valves (76a, 76b, 76c, 67, 96).

[0177] exist Figure 18 In the described example, the recovery device 7 has a first on / off valve 13a and a second on / off valve 13b. Alternatively, the recovery device 7 may also have a third on / off valve 13c.

[0178] A first on / off valve 13a is disposed between the air source AS and the first flow control valve 76a. More specifically, the first on / off valve 13a is disposed in the first air flow channel 77a. The first on / off valve 13a opens and closes the first air flow channel 77a between the air source AS and the first flow control valve 76a.

[0179] The second on / off valve 13b is disposed between the air source AS and the second flow control valve 76b. More specifically, the second on / off valve 13b is disposed in the second air passage 77b. The second on / off valve 13b opens and closes the second air passage 77b between the air source AS and the second flow control valve 76b.

[0180] The third on / off valve 13c is disposed between the air source AS and the third flow control valve 76c. More specifically, the third on / off valve 13c is disposed in the third air passage 77c. The third on / off valve 13c opens and closes the third air passage 77c between the air source AS and the third flow control valve 76c.

[0181] exist Figure 18 In the described example, the air supply device 9 has a fourth on / off valve 13d. The fourth on / off valve 13d is disposed between the air source AS and the fourth flow control valve 96. More specifically, the fourth on / off valve 13d is disposed in the air supply pipe 91. The fourth on / off valve 13d opens and closes the flow path of the air supply pipe 91 between the air source AS and the fourth flow control valve 96.

[0182] exist Figure 18 In the described example, the mixed fluid supply device 6 has a fifth on / off valve 13e. The fifth on / off valve 13e is disposed between the air source AS and the fifth flow control valve 67. More specifically, the fifth on / off valve 13e is disposed in the second air supply pipe 63. The fifth on / off valve 13e opens and closes the flow path of the second air supply pipe 63 between the air source AS and the fifth flow control valve 67.

[0183] (Controller 8)

[0184] The controller 8 controls the mixed fluid supply device 6 and the recovery device 7. Optionally, the controller 8 can also control the air supply device 9.

[0185] exist Figure 18In the described example, the controller 8 includes a processor 80, a memory 82 for storing programs and data, and a communication circuit 84. Figure 18 In the example described, the processor 80, memory 82, and communication circuit 84 are connected via bus 88.

[0186] The controller 8 can be composed of a microcontroller or a computer. The microcontroller integrates the processor 80, memory 82 and communication circuit 84 into an integrated circuit. The computer is respectively equipped with a CPU as the processor 80, a storage unit as the memory 82 and a communication unit as the communication circuit 84.

[0187] Controller 8 controls the air source AS. Controller 8 drives the air source AS by sending a drive command C to the air source AS (e.g., an air compressor).

[0188] The controller 8 controls the mixing fluid supply device 6. More specifically, the controller 8 sends a first set of control commands C1 to the mixing fluid supply device 6, and the mixing fluid supply device 6, upon receiving the first set of control commands C1, supplies a first flow rate of mixed fluid to the plurality of bearings 3. For example, the controller 8 supplies a mixed fluid containing oil and air to the plurality of bearings 3 using the mixing fluid supply device 6 by sending the first set of control commands C1 to the fifth on / off valve 13e and the pump 62.

[0189] Controller 8 controls recovery device 7. Controller 8 sends a second set of control commands C2 to recovery device 7, and recovery device 7, upon receiving the second set of control commands C2, recovers the oily fluid. For example, controller 8 recovers the oily fluid using recovery device 7 by sending the second set of control commands C2 to first on / off valve 13a, second on / off valve 13b, and third on / off valve 13c. When the opening degree of first flow control valve 76a is set to the first opening degree, poor bearing lubrication will not occur due to the suction force of first injector 75a. When the opening degree of second flow control valve 76b is set to the second opening degree, poor bearing lubrication will not occur due to the suction force of second injector 75b.

[0190] The controller 8 can also control the air supply device 9 to inject air from the air injection port OP1. The controller 8 sends a third set of control commands C3 to the air supply device 9, and the air supply device 9, receiving the third set of control commands C3, supplies a fourth type of air to the nozzle 49 formed in the housing 4. For example, the controller 8 supplies a fourth type of air to the nozzle 49 using the air supply device 9 by sending control command C3 to the fourth on / off valve 13d. A portion of the fourth type of air supplied to the nozzle 49 is injected from the air injection port OP1, and a portion of the fourth type of air supplied to the nozzle 49 is recovered by the recovery device 7 via the third recovery channel 73.

[0191] By appropriately setting the opening of the third flow control valve 76c and the opening of the fourth flow control valve 96, (1) the third oil-containing fluid containing oil that was not recovered by the first recovery channel 71 but passed through the first bearing 31a is recovered via the third recovery channel 73, (2) oil is prevented or suppressed from mixing into the air injected from the air injection port OP1, and (3) an air curtain is appropriately formed by the air injected from the air injection port OP1.

[0192] (First rotary drive device 5)

[0193] exist Figure 17 In the described example, the spindle lubrication device 1 of the machine tool includes a first rotary drive 5 that rotates the rotating body 2 (more specifically, the rotating shaft 20) about a first axis AX1. The first rotary drive 5 can also be a first motor. Figure 17 In the described example, the first rotary drive device 5 (more specifically, the first motor) has a stator 51 and a rotor 53. In this case, if current is supplied to the stator 51, the rotor 53 rotates about the first axis AX1 by electromagnetic force. Figure 17 In the example described, the stator 51 is fixed to the housing 4, and the rotor 53 is fixed to the rotating body 2 (more specifically, the rotating shaft 20).

[0194] exist Figure 17 In the described example, rotor 53 is disposed at the middle portion 23 of rotating shaft 20. Rotor 53 is disposed further in the second direction DR2 than the first bearing 31a, and further in the first direction DR1 than the second bearing 36b.

[0195] exist Figure 17 In the described example, the first rotary drive device 5 is disposed inside the housing 4. Alternatively, the first rotary drive device 5 may also be disposed outside the housing 4. For example, the first rotary drive device 5 disposed outside the housing 4 may also be configured to rotate the rotating body 2 by means of any power transmission mechanism (e.g., gears, belts, etc.).

[0196] (Processing head 10)

[0197] The spindle lubrication device 1 of the machine tool includes a machining head 10. Figure 19 In the recorded example, the processing head 10 has: (1) a rotating body 2 that holds the tool T; (2) a plurality of bearings 3, including a first bearing 31a and a second bearing 36b; (3) a housing 4 that supports the rotating body 2 by means of the plurality of bearings 3 so that it can rotate about a first axis AX1; and (4) a first rotation drive device 5 that causes the rotating body 2 to rotate about the first axis AX1.

[0198] (Rotating body 2)

[0199] exist Figure 19In the described example, the rotating body 2 has a rear end portion 22 and a front end portion 24 for holding the tool T. More specifically, the rotating body 2 (more specifically, the rotating shaft 20) has a rotating shaft body 21, a mounting portion 28 for mounting the tool T, and a rod-shaped member 291 connected to the mounting portion 28. The rod-shaped member 291 is disposed inside the rotating shaft body 21. Figure 19 In the described example, if the mounting drive 14 of the machining head 10 presses the rod-shaped member 291 toward the first direction DR1, the rod-shaped member 291 and the mounting portion 28 move relative to the rotating shaft body 21 in the first direction DR1. In this state, the tool T mounted on the mounting portion 28 can be replaced with another tool. After the tool is replaced, the force-applying member 293 (e.g., a disc spring) disposed on the rotating shaft 20 presses the rod-shaped member 291 toward the second direction DR2. Thus, the rod-shaped member 291 and the mounting portion 28 move relative to the rotating shaft body 21 in the second direction DR2.

[0200] exist Figure 20 In the described example, the rotating body 2 (more specifically, the rotating shaft body 21) has an inner circumferential surface 21n that contacts the tool holder HD. This inner circumferential surface 21n is, for example, a tapered surface whose diameter increases as it faces the first direction DR1.

[0201] exist Figure 21 In the recorded example, the rotating body 2 (more specifically, the rotation axis 20) has a first part 25, a second part 26, and a stepped surface 25a.

[0202] The first part 25 supports the inner ring 32a of the first bearing 31a. The first part 25 has a first outer peripheral surface 25u.

[0203] The second portion 26 has a second outer peripheral surface 26u with a smaller diameter than the first outer peripheral surface 25u. In other words, the diameter of the second outer peripheral surface 26u of the second portion 26 is smaller than the diameter of the first outer peripheral surface 25u of the first portion 25. The second portion 26 is disposed further toward the first direction DR1 side than the first portion 25.

[0204] The step surface 25a connects the first outer peripheral surface 25u of the first part 25 and the second outer peripheral surface 26u of the second part 26.

[0205] exist Figure 21 In the described example, the first part 25 and the second part 26 of the rotating body 2 are each composed of a portion of the rotating shaft body 21. Alternatively, at least a portion of the first part 25 and the second part 26 of the rotating body 2 may also be composed of a component other than the rotating shaft body 21 (e.g., an inner ring retainer separate from the rotating shaft body 21).

[0206] (Shell 4)

[0207] exist Figure 19 In the described example, the housing 4 has a front end portion 4a, a rear end portion 4b, and an intermediate portion 4c between the front end portion 4a and the rear end portion 4b.

[0208] like Figure 20 As illustrated, the front end portion 4a of the housing 4 supports the outer ring of the front bearing 31. Figure 20 In the example described, the front end portion 4a of the housing 4 supports the outer ring 33a of the first bearing 31a and the outer ring 33c of the third bearing 31c.

[0209] The housing 4 may also include an outwardly projecting flange 47. Figure 20 In the described example, flange 47 is disposed on the front end portion 4a of housing 4. An outlet port 71p of the first recovery channel 71 may also be provided on flange 47. Figure 20 In the described example, the first pipe 74a is connected to the outlet port 71p. Alternatively, the outlet port 73p of the third recovery channel 73 can be provided on the flange 47. Figure 20 In the described example, the aforementioned third pipe 74c is connected to the outlet port 73p. Alternatively, the inlet port 93p of the air supply channel 93 can be provided on the flange 47. Figure 20 In the described example, the aforementioned air supply pipe 91 is connected to the inlet port 93p. Figure 20 In the described example, a supply channel 66 is provided in the housing 4. Figure 20 In the recorded example, the supply channel 66 supplies a mixture of oil and air (more specifically, oil and gas) to the front bearing containing the first bearing 31a and the third bearing 31c.

[0210] The rear end portion 4b of the housing 4 supports the outer ring of the rear bearing 36. Figure 19 In the described example, the rear end portion 4b of the housing 4 supports the outer ring 37b of the second bearing 36b. The rear end portion 4b may also have an end plate 40b disposed at the end of the housing 4 on the second direction DR2 side.

[0211] exist Figure 19 In the described example, the middle portion 4c of the housing 4 has a cylindrical sidewall 40c. The middle portion 4c of the housing 4 (more specifically, the cylindrical sidewall 40c) can also support the stator 51 described above.

[0212] exist Figure 21 In the recorded example, the housing 4 (more specifically, the front end side portion 4a of the housing 4) has a third portion 41 and a fourth portion 42.

[0213] The third part 41 supports the outer ring 33a of the first bearing 31a. (See example...) Figure 22As illustrated, a first gap G1 is formed between the first portion 25 of the rotating body 2 and the third portion 41 of the housing. Figure 22 In the recorded example, the oil E that passed through the first bearing 31a exists in the first gap G1. Within this first gap G1, the oil E can exist in the form of oil vapor, oil mist, or liquid oil. Figure 22 In the described example, the first gap G1 is straight in the longitudinal section containing the first axis AX1. Alternatively, the first gap G1 can also be labyrinthine in the longitudinal section containing the first axis AX1. Alternatively or additionally, as... Figure 23 As illustrated, a notch CT may also be formed on a portion of the surface defining the first gap G1. This notch CT may be formed on the first outer peripheral surface 25u of the rotating body 2, or on the surface of the third portion 41 of the housing 4.

[0214] Part 4.42 specifies an annular receiving space SP that receives oil E from the first gap G1. Within the annular receiving space SP, the oil E can exist in the form of oil vapor, oil mist, or liquid oil. The shape of the annular receiving space SP is not limited; it is arbitrary.

[0215] exist Figure 23 In the described example, the aforementioned first gap G1 and an annular receiving space SP are arranged on a straight line LN parallel to the first axis AX1. In this case, the oil E present in the first gap G1 is smoothly guided into the annular receiving space SP.

[0216] exist Figure 23 In the recorded example, the fourth part 42 has an opening 45 that guides oil E from the annular containment space SP to the third recovery channel 73.

[0217] exist Figure 24 In the described example, a second gap G2, which is in fluid communication with the first gap G1, is formed between the shell 4 and the stepped surface 25a of the rotating body 2. Furthermore, a third gap G3, which is in fluid communication with the second gap G2, is formed between the shell 4 and the second outer peripheral surface 26u of the rotating body 2.

[0218] Imagine a path from the first gap G1 to the outside of the machining head 10. This path could be a cause of oil leakage. Figure 24 In the described example, a second gap G2 exists between the housing 4 and the stepped surface 25a in the path from the first gap G1 to the outside of the machining head 10. Therefore, the presence of the second gap G2 prevents oil from leaking out of the machining head 10 via the aforementioned path.

[0219] exist Figure 24In the described example, the extending direction of the first gap G1 is different from the extending direction of the second gap G2. Therefore, oil within the first gap G1 is prevented from moving towards the second gap G2. For example, oil moving downwards from the first gap G1 is prevented from entering the second gap G2. Figure 24 In the example described, the extension direction of the first gap G1 is the first direction DR1, and the extension direction of the second gap G2 is the radial direction DR3 (more specifically, the direction perpendicular to and toward the first axis AX1).

[0220] exist Figure 24 In the described example, the third gap G3 is connected to the second gap G2 via corner CN. Furthermore, the extending direction of the third gap G3 is different from the extending direction of the second gap G2. Figure 24 In the recorded example, the extension direction of the third gap G3 is the first direction DR1, and the extension direction of the second gap G2 is the radial direction DR3 (more specifically, the direction perpendicular to and toward the first axis AX1).

[0221] (Annular protrusion 44)

[0222] exist Figure 25 In the described example, the fourth part 42 has a base 43 connected to the third part 41 and an annular protrusion 44 protruding in the direction from the base 43 toward the first axis AX1. Additionally, in Figure 25 In order to make it easier to grasp the shape of the annular protrusion 44, a shadow formed by dots is added to the annular protrusion 44.

[0223] like Figure 24 As illustrated, the annular protrusion 44 has a first surface 44a facing the stepped surface 25a and a second surface 44b facing the outer peripheral surface (in other words, the second outer peripheral surface 26u) of the second part 26 of the rotating body 2.

[0224] Alternatively, the annular protrusion 44 may also have an annular protrusion 441 protruding in a direction away from the first axis AX1. The annular protrusion 441 faces both the stepped surface 25a and the annular receiving space SP. When the fourth part 42 (more specifically, the annular protrusion 44 of the fourth part 42) has an annular protrusion 441 protruding in a direction away from the first axis AX1, the oil E entering the annular receiving space SP is less likely to flow backward toward the second gap G2. Therefore, leakage of oil from the gap between the rotating body 2 and the front end 46 of the housing 4 to the processing head 10 is effectively suppressed.

[0225] exist Figure 25In the described example, the housing 4 has a first component CP1 (more specifically, an annular first component CP1) including the aforementioned annular protrusion 441 and a second component CP2 (more specifically, an annular second component CP2) supporting the first component CP1. When the first component CP1 including the annular protrusion 441 is a different component from the second component CP2, the design freedom of the internal shape of the housing 4 (e.g., the freedom of the shape of the annular receiving space SP) is increased.

[0226] exist Figure 25 In the described example, the first component CP1 and the second component CP2 each have portions facing the annular receiving space SP. In a longitudinal section passing through the first axis AX1, the first component CP1 may have a generally L-shaped shape, or it may have other shapes. The second component CP2 may also be an end plate disposed at the end of the housing 4 on the first direction DR1 side.

[0227] exist Figure 24 In the described example, the annular protrusion 44 has a first wall 440a defining the bottom surface of the annular receiving space SP (in other words, the end face of the annular receiving space SP on the first direction DR1 side) and a second wall 440b defining a second surface 44b facing the second outer peripheral surface 26u of the rotating body 2.

[0228] exist Figure 24 In the described example, the first wall 440a is an annular wall connected to the base 43 of the fourth portion 42 and extending radially inward in a DR3 direction. Furthermore, the second wall 440b is an annular wall connected to the inner edge of the first wall 440a and extending radially in a second direction DR2 direction. Additionally, an annular protrusion 441 is connected to the end of the second wall 440b on the second direction DR2 side and protrudes radially outward in a DR4 direction from that end.

[0229] The annular protrusion 44 may also have a first annular groove V1. Figure 24 In the described example, the first annular groove V1 is a groove facing the annular receiving space SP and recessed in the radial direction DR3. The first annular groove V1 prevents or inhibits the backflow of oil in the annular receiving space SP into the second gap G2.

[0230] exist Figure 24 In the described example, the fourth portion 42 of the housing 4 has a second annular groove V2. The second annular groove V2 is a groove that faces the annular receiving space SP and is recessed in a radially outward direction DR4 (in other words, away from the first axis AX1). Figure 24 In the example described, the second annular groove V2 is disposed in the fourth part 42 of the housing 4 in a manner opposite to the first annular groove V1.

[0231] exist Figure 26In the diagram, to easily grasp the shapes of the first annular groove V1 and the second annular groove V2, dashed lines represent the parts other than the first annular groove V1 and the second annular groove V2, while solid lines represent the first annular groove V1 and the second annular groove V2. Figure 26 In the described example, oil can be contained in both the first annular groove V1 and the second annular groove V2. In this case, the annular accommodating space SP includes the space defined by the first annular groove V1 and the space defined by the second annular groove V2, which can increase the overall volume of the annular accommodating space SP.

[0232] exist Figure 26 In the described example, the annular protrusion 44 has a third surface 44f that forms part of the end face 4f on the first direction DR1 side of the housing 4. This third surface 44f is the surface on the first direction DR1 side of the first wall 440a described above.

[0233] (Air injection port OP1 and nozzle 49)

[0234] exist Figure 24 In the example described, an air jet port OP1 communicating with the third gap G3 is formed between the front end 46 of the housing 4 and the rotating body 2.

[0235] Furthermore, the housing 4 is provided with an air supply channel 93 for the flow of fourth air supplied from the air supply pipe 91 and an outlet 49 for ejecting the fourth air. The outlet 49 ejects the fourth air received from the air supply channel 93 toward the third gap G3 in such a way that a first air flow from the third gap G3 toward the second gap G2 and a second air flow from the third gap G3 toward the air injection port OP1 are formed.

[0236] The fourth air ejected from the air jet port OP1 prevents foreign objects such as chips from entering the machining head 10 through the third gap G3. More specifically, the fourth air ejected from the air jet port OP1 forms an air curtain AC around the tool T or tool holder HD. This air curtain prevents foreign objects such as chips from entering the machining head 10 through the third gap G3.

[0237] exist Figure 24 In the described example, the fourth airflow from the third gap G3 toward the second gap G2 prevents oil E from entering the second gap G2 from the first gap G1 or the annular containment space SP. Furthermore, the fourth airflow from the third gap G3 toward the second gap G2 pushes any oil that has entered the second gap G2 back toward the annular containment space SP.

[0238] Additionally, at least a portion of the fourth air flowing from the third gap G3 toward the second gap G2 reaches the annular containment space SP. The air that reaches the annular containment space SP is recovered via the third recovery channel 73.

[0239] Air (or air containing trace amounts of oil) that is not recovered by the first recovery channel 71, the second recovery channel 72, and the third recovery channel 73 is discharged from the gap of the processing head 10 to the outside of the processing head 10 (see reference). Figure 19 (The dashed arrow in the middle).

[0240] (Third Implementation)

[0241] Reference Figures 1 to 31 The machine tool 100 in the third embodiment will be described. Figure 27 This is a schematic perspective view illustrating an example of the machine tool 100 in the third embodiment. Figure 28 This is a schematic perspective view illustrating another example of the machine tool 100 in the third embodiment. Figure 29 This diagram schematically illustrates a situation where the control device 140 can control multiple controllable devices. Figure 30 This is a diagram illustrating an example of the configuration of the recycling container 792. Figure 31 This is another example of the configuration used to illustrate the recycling container 792.

[0242] In the third embodiment, the description focuses on the differences from the first and second embodiments. Furthermore, in the third embodiment, repetitive descriptions of matters already described in the first or second embodiments are omitted. Therefore, in the third embodiment, even without explicit explanation, matters already described in the first or second embodiments can certainly be applied to the third embodiment.

[0243] like Figure 27 and Figure 29 As illustrated, the machine tool 100 in the third embodiment includes a machining head 10, a mixed fluid supply device 6, a recovery device 7, a workpiece support device 110 for supporting the workpiece W, a moving device 120 for moving the machining head 10 relative to the workpiece support device 110, and a control device 140.

[0244] The processing head 10, the mixed fluid supply device 6, and the recovery device 7 have already been described in the first or second embodiment, so a repeated description of their structure is omitted.

[0245] (Workpiece support device 110)

[0246] exist Figure 27In the described example, the workpiece support device 110 has a support member 111 (more specifically, a worktable 111a) for supporting the workpiece W and a second rotary drive device 112 for rotating the support member 111 (more specifically, the worktable 111a) about a second axis AX2. The workpiece support device 110 may also have a tilting movement device 113 for tilting the worktable 111a about an axis AX3 perpendicular to the second axis AX2.

[0247] Alternatively, such as Figure 28 As illustrated, the workpiece support device 110 may also have a chuck 111b for holding the workpiece W and a second rotary drive device 112 for rotating the chuck 111b about the second axis AX2.

[0248] (Mobile device 120)

[0249] The moving device 120 moves the machining head 10 relative to the workpiece support device 110. The moving device 120 may also be a device capable of three-dimensional movement of the machining head 10. Alternatively, the moving device 120 may be capable of moving the machining head 10 along the Z-axis, which is parallel to the vertical direction. Alternatively, the moving device 120 may be capable of moving the machining head 10 along the X-axis, which is parallel to the horizontal direction. Furthermore, the moving device 120 may be capable of moving the machining head 10 along the Y-axis, which is perpendicular to both the X-axis and Z-axis. Figure 27 and Figure 28 In the example described, the processing head 10 is supported by the base 130 by means of the moving device 120.

[0250] (Control device 140)

[0251] The control device 140 controls at least the first rotary drive device 5, the mixing fluid supply device 6, and the moving device 120. Optionally, the control device 140 may also control the recovery device 7.

[0252] like Figure 29 As illustrated, the control device 140 includes a hardware processor 141 (hereinafter referred to as "processor 141"), a memory 142, a communication circuit 144, and an input device 146 (e.g., a display 146a with a touch panel). The processor 141, memory 142, communication circuit 144, and input device 146 are interconnected via a bus 148.

[0253] The memory 142 stores data 142a required for machining the workpiece and programs 142b for operating the various components of the machine tool 100. The memory 142 is a storage medium that can be read by the processor 141 of the control device 140. The memory 142 may be, for example, a non-volatile or volatile semiconductor memory such as RAM, ROM, or flash memory, or a disk, or other forms of memory.

[0254] The input device 146 is not limited to a display 146a with a touch panel. For example, the control device 140 may also include input devices 146 such as buttons, switches, joysticks, pointing devices, and keyboards, as well as a display for displaying data or other information input to the input device 146. Furthermore, the memory 142 may be distributed across multiple locations. For example, a portion of the memory 142 may be included in cloud storage.

[0255] Alternatively, multiple computers can collaborate to function as the control device 140. Figure 29 In the described example, the control device 140 includes a main control device 140a and the aforementioned controller 8. In other words, the main control device 140a and the controller 8 cooperate to function as the control device 140. The controller 8 operates based on instructions received from the main control device 140a. Furthermore, in the case where the function of the controller 8 described in the first or second embodiment is embedded in the main control device 140a, the controller 8 is omitted. In other words, the main control device 140a itself functions as the controller 8.

[0256] exist Figure 29 In the described example, if the control device 14 sends a first set of control commands C1 to the mixing fluid supply device 6, the mixing fluid supply device 6, receiving the first set of control commands C1, supplies a first flow rate of mixing fluid to the plurality of bearings 3. Thus, a mixing fluid containing oil and air is supplied to the plurality of bearings 3.

[0257] exist Figure 29 In the recorded example, if the control device 140 sends a second set of control commands C2 to the recovery device 7, the recovery device 7 that receives the second set of control commands C2 will recover the oily fluid.

[0258] For example, the recovery device 7, which receives the control command C2 from the second group, supplies first air to the first injector 75a. The first air creates a negative pressure in the first conduit 74a, which draws the first oil-containing fluid from the first recovery channel 71 through the first conduit 74a. When the opening of the first flow control valve 76a is set to the first opening degree, the bearing will not experience poor lubrication due to the suction force of the first injector 75a.

[0259] For example, the recovery device 7, which receives the control command C2 from the second group, supplies second air to the second injector 75b. The second air creates a negative pressure in the second pipe 74b, which draws the second oil-containing fluid from the second recovery channel 72 through the second pipe 74b. When the opening of the second flow control valve 76b is set to the second opening degree, the bearing will not experience poor lubrication due to the suction force of the second injector 75b.

[0260] For example, the recovery device 7, which receives the control command C2 from the second group, supplies third air to the third injector 75c. The third air generates a negative pressure in the third pipe 74c, and the third oil-containing fluid is drawn from the third recovery channel 73 through the third pipe 74c using this negative pressure.

[0261] exist Figure 29 In the example described, if the control device 140 sends a control command C3 to the air supply device 9, the air supply device 9 that receives the control command C3 supplies a fourth type of air to the nozzle 49 formed in the housing 4.

[0262] A portion of the fourth air ejected from nozzle 49 is ejected from air injection port OP1. An air curtain is formed using the air ejected from air injection port OP1. Furthermore, a portion of the fourth air ejected from nozzle 49 is recovered by recovery device 7 via third recovery channel 73.

[0263] exist Figure 29 In the described example, if the control device 140 sends a first movement command J1 to the moving device 120, the moving device 120, receiving the first movement command J1, moves the machining head 10 relative to the workpiece support device 110. In this way, the tool T held on the rotating body 2 can be moved toward the workpiece W.

[0264] exist Figure 29 In the described example, if the control device 140 sends a first rotation command R1 to the first rotary drive device 5, the first rotary drive device 5, upon receiving the first rotation command R1, causes the rotating body 2 to rotate around the first axis AX1. In this way, the workpiece W can be machined using the tool T held on the rotating body 2.

[0265] Alternatively, the control device 140 may be able to control the second rotary drive device 112. For example, if the control device 140 sends a second rotation command R2 to the second rotary drive device 112, the second rotary drive device 112 that receives the second rotation command R2 causes the support member 111 supporting the workpiece W to rotate around the second axis AX2.

[0266] The control device 140 generates control commands by executing program 142b stored in memory 142 through processor 141. Furthermore, communication circuit 144 sends these control commands to the controlled device (more specifically, the first rotary drive 5, the moving device 120, the mixing fluid supply device 6, the recovery device 7, the air supply device 9, and the second rotary drive 112, etc.). Thus, by executing program 142b through processor 141, the control device 140 can control the first rotary drive 5, the moving device 120, the mixing fluid supply device 6, the recovery device 7, the air supply device 9, and the second rotary drive 112, etc.

[0267] (Configuration of recycling container 792)

[0268] exist Figure 30 In the described example, the machine tool 100 includes: an outer wall 171 that surrounds the workpiece support device 110 and the processing head 10 when viewed from above; an opening 173 formed in the outer wall 171 for workpieces to be moved into the workpiece support device 110 to pass through; and a door 175 for opening and closing the opening 173.

[0269] exist Figure 30 In the described example, the recovery container 792 is positioned so that the operator's hand can reach it from outside the machine tool via the opening 173. In other words, the recovery container 792 is positioned near the opening 173. In this case, the operator can easily remove the drained oil recovered into the recovery container 792 from the machine tool 100. Alternatively, as... Figure 31 As illustrated, the recycling container 792 can also be configured further outward than the outer wall 171.

[0270] When the recovery container 792 is positioned near the opening 173, or further outward than the outer wall 171, the pipe from the processing head 10 to the recovery container 792 becomes longer. If the pipe becomes longer, the pressure loss of the fluid flowing in the pipe becomes greater, making it more difficult to optimize lubrication in each of the multiple bearings individually. In the third embodiment, the attraction force acting on each injector can be set individually. Therefore, even with a long pipe leading to the recovery container 792, lubrication can be optimized in each of the multiple bearings individually by appropriately setting each attraction force. In particular, by taking into account the first condition CD1 and the second condition CD2 (or the third condition CD3 and the fourth condition CD4) mentioned above when setting the opening of each flow control valve (75a, 75b, ...), the attraction force acting on each injector can be easily and appropriately set.

[0271] (How to use the machine tool)

[0272] Reference Figures 1 to 32 The method of using the machine tool in the implementation method is described. Figure 32 This is a flowchart illustrating an example of how a machine tool is used in an implementation method.

[0273] The machine tool used in the method of using the machine tool is, for example, the machine tool 100 in the third embodiment. The machine tool 100 and its constituent elements have been described in the first to third embodiments, so a repeated description of the machine tool 100 and its constituent elements is omitted.

[0274] In the first step ST1, the first discharge flow rate and the second discharge flow rate are derived. The first step ST1 is the discharge flow rate deriving process.

[0275] The discharge flow extraction process (first step ST1) is included in the second condition CD2 mentioned above (refer to...). Figure 5 or Figure 9 When the flow rate of the first oily fluid discharged from the first recovery channel 71 to the outside of the first recovery channel 71 (e.g., outside the shell 4) is defined as the first discharge flow rate, the first discharge flow rate is derived by measurement or simulation.

[0276] The discharge flow extraction process (first step ST1) is included in the second condition CD2 mentioned above (refer to...). Figure 5 or Figure 9 When the flow rate of the second oil-containing fluid discharged from the second recovery channel 72 to the outside of the second recovery channel 72 (e.g., outside the housing 4) is defined as the second discharge flow rate, the second discharge flow rate is derived by measurement or simulation.

[0277] Furthermore, when the machine tool 100 includes a third recovery flow channel 73, an air supply flow channel 93, and an air injection port OP1, the discharge flow export process (first step ST1) can also be included in the aforementioned fourth condition CD4 (refer to...). Figure 16 Furthermore, when the flow rate of the first oil-containing fluid discharged from the first recovery channel 71 to the outside of the first recovery channel 71 (e.g., outside the casing 4) is defined as the first discharge flow rate under the fourth condition CD4 (which is a variation of the second condition CD2), this first discharge flow rate is derived by measurement or simulation. Additionally, the discharge flow rate derivation process (first step ST1) can also be included in the aforementioned fourth condition CD4 (refer to...). Figure 16 When the flow rate of the second oil-containing fluid discharged from the second recovery channel 72 to the outside of the second recovery channel 72 (e.g., outside the housing 4) is defined as the second discharge flow rate, the second discharge flow rate is derived by measurement or simulation.

[0278] In the second step ST2, the first recycled flow and the second recycled flow are exported. The second step ST2 is the recycled flow export process.

[0279] The process of recovering flow and exporting (second step ST2) is included in the first condition CD1 mentioned above (refer to...). Figure 4 or Figure 8 When the flow rate of the first oil-containing fluid flowing in the first pipe 74a is defined as the first recovery flow rate, the first recovery flow rate is derived by measurement or simulation.

[0280] The process of recovering flow and exporting (second step ST2) is included in the first condition CD1 mentioned above (refer to...). Figure 4 or Figure 8 When the flow rate of the second oil-containing fluid flowing in the second pipe 74b is defined as the second recovery flow rate, the second recovery flow rate is derived by measurement or simulation.

[0281] Furthermore, when the machine tool 100 includes a third recovery flow channel 73, an air supply flow channel 93, and an air injection port OP1, the recovery flow export process (second step ST2) can also be included in the aforementioned third condition CD3 (see reference). Figure 15 Furthermore, under the third condition CD3 (which is a variation of the first condition CD1), when the flow rate of the first oil-containing fluid flowing in the first pipe 74a is defined as the first recovery flow rate, the first recovery flow rate is derived by measurement or simulation. Additionally, the recovery flow rate derivation process (second step ST2) can also be included in the aforementioned third condition CD3 (refer to...). Figure 15 When the flow rate of the second oil-containing fluid flowing in the second pipe 74b is defined as the second recovery flow rate, the second recovery flow rate is derived by measurement or simulation.

[0282] In the third step ST3, the opening degree of the first flow control valve 76a and the opening degree of the second flow control valve 76b are derived. The third step ST3 is the opening degree derivation process.

[0283] The opening determination step (third step ST3) includes determining the first opening of the first flow control valve 76a such that the ratio of the first recovered flow rate to the first discharged flow rate is within a predetermined range. For example, the opening determination step includes determining the first opening of the first flow control valve 76a such that the first recovered flow rate is more than 1 and less than 1.5 times the first discharged flow rate (more preferably, more than 1 and less than 1.2 times the first discharged flow rate). Alternatively, the correlation between the opening of the first flow control valve 76a and the first recovered flow rate can be determined, and the first opening can be determined based on this correlation. Alternatively, the first opening can be determined through repeated trials.

[0284] The opening determination step (third step ST3) includes determining the second opening of the second flow control valve 76b such that the ratio of the second recovered flow rate to the second discharged flow rate is within a predetermined range. For example, the opening determination step includes determining the second opening of the second flow control valve 76b such that the second recovered flow rate is more than 1 and less than 1.5 times the second discharged flow rate (more preferably, more than 1 and less than 1.2 times the second discharged flow rate). Alternatively, the correlation between the opening of the second flow control valve 76b and the second recovered flow rate can be determined, and the second opening can be determined based on this correlation. Alternatively, the second opening can be determined through repeated trials.

[0285] Additionally, if the machine tool 100 includes a third recovery flow channel 73, an air supply flow channel 93, and an air injection port OP1, the opening exit process (third step ST3) may also include exiting from the injection port 49 (see reference). Figure 14 The flow rate of the fourth air ejected is greater than that from the air injection port OP1 (refer to...). Figure 14 The opening degree of the third flow control valve 76c (hereinafter referred to as "third opening") and the opening degree of the fourth flow control valve 96 (hereinafter referred to as "fourth opening") of the injected air flow rate.

[0286] More specifically, the opening exit process (third step ST3) may also include exiting (1) from the nozzle 49 (refer to) Figure 14 The flow rate of the fourth air ejected is greater than that from the air injection port OP1 (refer to...). Figure 14 (2) The flow rate of the air injected from the air injection port OP1 is greater than the third flow rate mentioned above (more specifically, the flow rate greater than the design lower limit value for forming an air curtain), and the third opening degree of the third flow control valve 76c and the fourth opening degree of the fourth flow control valve 96 are set to the third opening degree.

[0287] For example, the first steps ST1 to the third steps ST3 described above are performed before the spindle lubrication device 1 (or machine tool 100) is shipped to the customer. More specifically, the first steps ST1 to the third steps ST3 described above are performed before the machine tool 100 is installed in the customer's factory. Furthermore, for example, the fourth steps ST4 to the sixth steps ST6 described later are performed after the machine tool 100 is installed in the customer's factory. More specifically, the fourth steps ST4 to the sixth steps ST6 described later are performed when the workpiece is machined by the machine tool 100.

[0288] In the fourth step ST4, a mixed fluid containing oil and air is supplied to multiple bearings 3. The fourth step ST4 is the mixed fluid supply process. The mixed fluid supply process is performed using a mixed fluid supply device 6.

[0289] In the fifth step ST5, the recovery device 7 is activated. The fifth step ST5 is the operation process of the recovery device. This operation process includes activating the recovery device 7 with the opening of the first flow control valve 76a set to the aforementioned first opening and the opening of the second flow control valve 76b set to the aforementioned second opening. Furthermore, if the machine tool 100 includes a third recovery channel 73, the recovery device operation process includes recovering, via the third recovery channel 73, the oil-containing third fluid that was not recovered by the first recovery channel 71 but passed through the first bearing 31a. More specifically, the recovery device operation process may also include activating the recovery device 7 with the opening of the third flow control valve 76c set to the aforementioned third opening.

[0290] In step ST6, the workpiece is machined. Step ST6 is the workpiece machining process. In the workpiece machining process, the workpiece W is machined by a tool T held on the rotating body 2 and rotating about the first axis AX1.

[0291] Steps ST4 through ST6 are executed in parallel. More specifically, during the execution of the workpiece processing procedure, the recovery device 7 operates when the mixed fluid supply device 6 supplies a mixed fluid containing oil and air to multiple bearings 3, and the opening of the first flow control valve 76a is set to the first opening and the opening of the second flow control valve 76b is set to the second opening.

[0292] When the recovery device 7 operates with the first flow control valve 76a set to the aforementioned first opening degree, the first oily fluid is appropriately recovered via the first recovery channel 71 and the first pipe 74a. Furthermore, the bearing lubrication is not compromised due to the suction force of the first injector 75a. Preferably, the first oily fluid that has passed through the first injector 75a is then transported to the exhaust purifier 791 via the exhaust pipe 78.

[0293] When the recovery device 7 operates with the second flow control valve 76b set to the aforementioned second opening degree, the second oily fluid is appropriately recovered via the second recovery flow channel 72 and the second pipe 74b. Furthermore, the bearing lubrication is not compromised due to the suction force of the second injector 75b. Preferably, the second oily fluid that has passed through the second injector 75b is then transported to the exhaust purifier 791 via the exhaust pipe 78.

[0294] In addition, when the machine tool 100 includes an air supply channel 93 and an air jet port OP1, the workpiece processing step (sixth step ST6) is preferably performed in the following states: (1) a state in which a fourth air is supplied to the air supply channel 93 provided in the housing, (2) a state in which a portion of the fourth air is jetted as an air curtain from the air jet port OP1 formed between the rotating body 2 and the front end 46 of the housing 4, and (3) a state in which the flow rate of the fourth air supplied to the air supply channel 93 is greater than the flow rate of the air jetted from the air jet port OP1.

[0295] More specifically, it is preferable that the recovery device 7 operates when the opening of the third flow control valve 76c is set to the aforementioned third opening, and the air supply device 9 operates when the opening of the fourth flow control valve 96 is set to the aforementioned fourth opening. When the recovery device 7 operates when the opening of the third flow control valve 76c is set to the aforementioned third opening, during the execution of the workpiece processing step (sixth step ST6), the third oil-containing fluid that was not recovered by the first recovery flow channel 71 but passed through the first bearing 31a is recovered via the third recovery channel 73. Furthermore, when the recovery device 7 operates when the opening of the third flow control valve 76c is set to the aforementioned third opening, and the air supply device 9 operates when the opening of the fourth flow control valve 96 is set to the aforementioned fourth opening, (1) oil is prevented or suppressed from mixing into the air injected from the air injection port OP1, and (2) an air curtain is appropriately formed using the air injected from the air injection port OP1.

[0296] This invention is not limited to the above-described embodiments or modifications. It is evident that appropriate modifications or alterations can be made to the embodiments or modifications within the scope of the inventive concept. Furthermore, various techniques employed in the embodiments or modifications can be applied to other embodiments or modifications as long as they do not create technical contradictions. Moreover, any additional structures in the embodiments or modifications can be appropriately omitted.

[0297] For example, in Figure 27 In the example described, machine tool 100 is a vertical machining center. Alternatively, machine tool 100 in the embodiment could also be a horizontal machining center. Furthermore, machine tool 100 could also be a multi-functional machining machine capable of performing machining other than cutting.

[0298] Explanation of reference numerals in the attached figures

[0299] 1. 1A, 1A', 1B Spindle lubrication device; 2 Rotating body; 3 Bearing; 4 Housing; 4a Front end portion of housing; 4b Rear end portion of housing; 4c Middle portion of housing; 4f End face of housing; 5 First rotary drive device; 6 Mixed fluid supply device; 7 Recovery device; 8 Controller; 9 Air supply device; 10 Machining head; 11a First flow meter; 11b Second flow meter; 12 Main air flow channel; 13 On / off valve; 13a First on / off valve; 13b Second on / off valve; 13c Third on / off valve; 13d Fourth on / off valve; 13e Fifth on / off valve; 14 Mounting drive device; 20 Rotating shaft; 21 Rotating shaft body; 21n Inner circumferential surface of rotating body; 22 Rear end of rotating body; 23 Middle portion of rotating body; 24 Front end of rotating body; 25 First portion of rotating body; 25a Stepped surface of rotating body; 25u 26 Second part of the rotating body, 26u Second outer peripheral surface, 28 Mounting part, 31 Front bearing, 31a First bearing, 31c Third bearing, 32a, 32c Inner rings, 33a, 33c Outer rings, 34a, 34c Rolling elements, 36 Rear bearing, 36b Second bearing, 37b Outer ring, 40b End plate of the housing, 40c Side wall of the housing, 41 Third part of the housing, 42 Fourth part of the housing, 43 Base of the fourth part, 44 Annular protrusion, 44a First surface, 44b Second surface, 44f Third surface, 45 Opening, 46 Front end of the housing, 47 Flange, 49 Spray outlet, 51 Stator, 53 Rotor, 61 Oil tank, 62 Pump, 63 Second air supply pipe, 64 Mixer, 66 Supply channel, 67 Fifth flow control valve, 68 Mixed fluid supply pipe, 71 First recovery channel, 71p Outlet port, 72 Second recovery channel, 73 Third recovery channel, 73p Outlet port, 74 Pipe, 74a First pipe, 74b Second pipe, 74c Third pipe, 75 Ejector, 75' Negative pressure generating device, 75a First ejector, 75b Second ejector, 75c Third ejector, 76a First flow control valve, 76b Second flow control valve, 76c Third flow control valve, 77a First air channel, 77b Second air channel, 77c Third air channel, 78 Exhaust pipe, 80 Processor, 82 Memory, 84 Communication circuit, 88 Bus, 91 Air supply pipe, 93 Air supply channel, 93p Inlet port, 96 Fourth flow control valve, 100 Machine tool, 110 Workpiece support device, 111 Support component, 111a Worktable, 111b Chuck, 112 Second rotary drive device, 113 tilting movement device, 120 movement device, 130 base, 140 control device, 140a main control device.141 Hardware processor, 142 Memory, 142a Data, 142b Program, 144 Communication circuit, 146 Input device, 146a Display with touch panel, 148 Bus, 171 Outer wall, 173 Opening, 175 Door, 291 Rod-shaped member, 293 Force-applying member, 440a First wall, 440b Second wall, 441 Annular protrusion, 751, 751a, 751b, 751c Inlet port, 752, 752a, 752b, 752c Outlet port, 753, 753a, 753b, 753c Vacuum port, 791 Exhaust purifier, 792 Recovery container, AC Air curtain, AS, AS1, AS2, AT Air source, C Drive command, C1, C2, C3 Control command, CN Corner, CP1 First component, CP2 Second component, CT cut, E, E1 oil, G clearance, G1 first clearance, G2 second clearance, G3 third clearance, HD tool holder, J1 first movement command, OP1 air jet, R1 first rotation command, R2 second rotation command, SP annular receiving space, T tool, V1 first annular groove, V2 second annular groove, W workpiece.

Claims

1. A spindle lubrication device for a machine tool, comprising: Rotating body, holding the tool; Multiple bearings, including a first bearing and a second bearing; The housing supports the rotating body by means of the plurality of bearings, enabling it to rotate about a first axis; A mixed fluid supply device supplies a mixed fluid comprising oil and air to the plurality of bearings; as well as The recovery device recovers oily fluid containing the oil. The recycling device includes: Multiple recovery channels are provided in the housing to recover the oil-containing fluid from the multiple bearings; Multiple injectors are disposed outside the housing; and Multiple flow control valves, The plurality of recycling channels include: The first recovery channel primarily recovers the first oil-containing fluid discharged from at least one bearing including the first bearing; and The second recovery channel primarily recovers the second oil-containing fluid discharged from at least one bearing containing the second bearing. The plurality of injectors includes: A first injector generates negative pressure using first air supplied from a first air passage, thereby drawing the first oil-containing fluid from the first recovery passage; and The second injector generates negative pressure using second air supplied from the second air channel, thereby drawing the second oil-containing fluid from the second recovery channel. The plurality of flow control valves include: A first flow control valve adjusts the flow rate of the first air supplied from the first air passage to the first injector; and The second flow control valve adjusts the flow rate of the second air supplied from the second air passage to the second injector. The spindle lubrication device of the machine tool also includes multiple pipes, including a first pipe that fluidly connects the first recovery channel to the first ejector, and a second pipe that fluidly connects the second recovery channel to the second ejector. Under the first condition that the plurality of pipes are respectively fluidly connected to the plurality of recovery channels, and the mixed fluid is supplied at a first flow rate from the mixed fluid supply device to the plurality of bearings, the flow rate of the first oil-containing fluid flowing in the first pipe is defined as the first recovery flow rate. Under the second condition, which differs from the first condition in that only the plurality of pipes are fluidly separated from the plurality of recovery channels, the flow rate of the first oil-containing fluid discharged from the first recovery channel to the outside of the first recovery channel is defined as the first discharge flow rate. The opening of the first flow control valve is set such that the first recovery flow rate is within a range of more than 1 and less than 1.5 times the first discharge flow rate. Under the first condition, the flow rate of the second oil-containing fluid flowing in the second pipe is defined as the second recovery flow rate, and under the second condition, the flow rate of the second oil-containing fluid discharged from the second recovery channel to the outside of the second recovery channel is defined as the second discharge flow rate, and the opening of the second flow control valve is set such that the second recovery flow rate is within a range of more than 1 and less than 1.5 times the second discharge flow rate.

2. The spindle lubrication device for a machine tool according to claim 1, wherein, The plurality of recovery channels includes a third recovery channel, which recovers a third oil-containing fluid, including the oil, that was not recovered by the first recovery channel but passed through the first bearing. The plurality of pipes includes a third pipe that fluidly connects the third recovery channel to the third ejector. The plurality of injectors includes the third injector, which uses third air supplied from a third air passage to create negative pressure in the third conduit, drawing the third oil-containing fluid from the third recovery passage via the third conduit. The plurality of flow control valves includes a third flow control valve that adjusts the flow rate of the third air supplied from the third air passage to the third injector.

3. The spindle lubrication device for a machine tool according to claim 1, wherein, The plurality of recovery channels includes a third recovery channel, which recovers a third oil-containing fluid, including the oil, that was not recovered by the first recovery channel but passed through the first bearing. The plurality of injectors includes a third injector that generates negative pressure using third air supplied from a third air channel, thereby drawing the third oil-containing fluid from the third recovery channel. The plurality of flow control valves includes a third flow control valve that adjusts the flow rate of the third air supplied from the third air passage to the third injector.

4. The spindle lubrication device for a machine tool according to claim 3, wherein, The rotating body has: Rear end; The cutting tool is held at the front end; The first part, the inner ring supporting the first bearing, has a first outer peripheral surface; The second portion has a second outer peripheral surface with a smaller diameter compared to the first outer peripheral surface, and is positioned further toward the first direction than the first portion when the direction from the rear end to the front end is defined as a first direction; and A stepped surface connects the first outer peripheral surface and the second outer peripheral surface. The housing has: The third part is the outer ring supporting the first bearing; and The fourth part specifies an annular receiving space for receiving the oil from the first gap between the first part and the third part. The fourth part has an opening that guides the oil from the annular receiving space to the third recovery channel. A second gap, which is in fluid communication with the first gap, is formed between the housing and the stepped surface. A third gap is formed between the housing and the second outer peripheral surface, which is in fluid communication with the second gap.

5. The spindle lubrication device for a machine tool according to claim 4, wherein, The fourth part has an annular protrusion that projects away from the first axis. The annular protrusion faces both the stepped surface and the annular receiving space.

6. The spindle lubrication device for a machine tool according to any one of claims 3 to 5, wherein, The spindle lubrication device of the machine tool also includes an air supply device. The air supply device includes: An air source is located outside the housing; An air supply channel is provided in the housing; An air supply pipe connects the air source to the air supply channel, supplying a fourth type of air to the air supply channel; and The fourth flow control valve adjusts the flow rate of the fourth air supplied from the air supply pipe to the air supply channel. An air injection port is formed between the front end of the rotating body and the housing. An outlet is formed in the housing, which ejects the fourth air received from the air supply channel into the gap in such a manner that a first flow from the gap between the rotating body and the housing toward the third recovery channel and a second flow from the gap toward the air injection port are both formed.

7. The spindle lubrication device for a machine tool according to claim 6, wherein, The spindle lubrication device of the machine tool also includes multiple pipes, comprising: a first pipe fluidly connecting the first recovery channel to the first ejector; a second pipe fluidly connecting the second recovery channel to the second ejector; and a third pipe fluidly connecting the third recovery channel to the third ejector. Under the third condition where the plurality of pipes are respectively fluidly connected to the plurality of recovery channels, a first flow rate of the mixed fluid is supplied from the mixed fluid supply device to the plurality of bearings, and a fourth condition where a second flow rate of air is supplied to the air supply channel, the flow rate of the first oil-containing fluid flowing in the first pipe is defined as the first recovery flow rate. Under the fourth condition, which differs from the third condition in that only the plurality of pipes are fluidly separated from the plurality of recovery channels, the flow rate of the first oil-containing fluid discharged from the first recovery channel to the outside of the first recovery channel is defined as the first discharge flow rate. The opening of the first flow control valve is set such that the first recovery flow rate is within a range of more than 1 and less than 1.5 times the first discharge flow rate. Under the third condition, the flow rate of the second oily fluid flowing in the second pipe is defined as the second recovery flow rate, and under the fourth condition, the flow rate of the second oily fluid discharged from the second recovery channel to the outside of the second recovery channel is defined as the second discharge flow rate. The opening of the second flow control valve is set such that the second recovery flow rate is within a range of more than 1 and less than 1.5 times the second discharge flow rate.

8. The spindle lubrication device for a machine tool according to claim 7, wherein, The opening degrees of the third flow control valve and the fourth flow control valve are set such that the flow rate of the fourth air ejected from the nozzle is greater than the flow rate of the air ejected from the air injection port.

9. A machine tool comprising: A machining head includes: a rotating body for holding a cutting tool; a plurality of bearings, including a first bearing and a second bearing; a housing for supporting the rotating body to be rotatable by means of the plurality of bearings; and a first rotation drive device for rotating the rotating body about a first axis. A mixed fluid supply device supplies a mixed fluid comprising oil and air to the plurality of bearings; A recovery device for recovering oily fluid containing the oil; Workpiece support device, used to support the workpiece; A moving device that moves the processing head relative to the workpiece support device; as well as The control device controls at least the first rotary drive device, the mixed fluid supply device, and the moving device. The recycling device includes: Multiple recovery channels are provided in the housing to recover the oil-containing fluid from the multiple bearings; Multiple injectors are disposed outside the housing; and Multiple flow control valves, The plurality of recycling channels include: The first recovery channel primarily recovers the first oil-containing fluid discharged from at least one bearing including the first bearing; and The second recovery channel primarily recovers the second oil-containing fluid discharged from at least one bearing containing the second bearing. The plurality of injectors includes: A first injector generates negative pressure using first air supplied from a first air passage, thereby drawing the first oil-containing fluid from the first recovery passage; and The second injector generates negative pressure using second air supplied from the second air channel, thereby drawing the second oil-containing fluid from the second recovery channel. The plurality of flow control valves include: A first flow control valve adjusts the flow rate of the first air supplied from the first air passage to the first injector; and The second flow control valve adjusts the flow rate of the second air supplied from the second air passage to the second injector. The machine tool also includes multiple pipes, including a first pipe that fluidly connects the first recovery channel to the first ejector, and a second pipe that fluidly connects the second recovery channel to the second ejector. Under the first condition that the plurality of pipes are respectively fluidly connected to the plurality of recovery channels, and the mixed fluid is supplied at a first flow rate from the mixed fluid supply device to the plurality of bearings, the flow rate of the first oil-containing fluid flowing in the first pipe is defined as the first recovery flow rate. Under the second condition, which differs from the first condition in that only the plurality of pipes are fluidly separated from the plurality of recovery channels, the flow rate of the first oil-containing fluid discharged from the first recovery channel to the outside of the first recovery channel is defined as the first discharge flow rate. The opening of the first flow control valve is set such that the first recovery flow rate is within a range of more than 1 and less than 1.5 times the first discharge flow rate. Under the first condition, the flow rate of the second oil-containing fluid flowing in the second pipe is defined as the second recovery flow rate, and under the second condition, the flow rate of the second oil-containing fluid discharged from the second recovery channel to the outside of the second recovery channel is defined as the second discharge flow rate, and the opening of the second flow control valve is set such that the second recovery flow rate is within a range of more than 1 and less than 1.5 times the second discharge flow rate.

10. The machine tool according to claim 9, further comprising: The outer wall, when viewed from above, surrounds the workpiece support device and the machining head; An opening is formed on the outer wall for the workpiece to be moved into the workpiece support device; as well as Door, opening and closing the aforementioned opening, The recycling device includes: An exhaust pipe that receives exhaust gas from the plurality of injectors; as well as The recovery container is fluidly connected to the exhaust pipe. The recycling container is positioned where the operator's hand can reach it from outside the machine tool via the opening, or positioned further outward than the outer wall.

11. A method of using a machine tool, as described in claim 9, comprising: In the second condition where the multiple pipes separate the fluid from the multiple recovery channels and the mixed fluid is supplied with a first flow rate from the multiple bearings by the mixed fluid supply device, the flow rate of the first oily fluid discharged from the first recovery channel to the outside of the first recovery channel is defined as the first discharge flow rate, and the process of deriving the first discharge flow rate by measurement or simulation. The process of deriving the second discharge flow rate by measuring or simulating when the flow rate of the second oil-containing fluid discharged from the second recovery channel to the outside of the second recovery channel under the second condition is defined as the second discharge flow rate; In the first condition that the multiple pipes are respectively fluidly connected to the multiple recovery channels and the mixed fluid of the first flow rate is supplied from the mixed fluid supply device to the multiple bearings, the process of deriving the first recovery flow rate by measuring or simulating the flow rate of the first oil-containing fluid flowing in the first pipe is defined as the first recovery flow rate. The process of deriving the second recovery flow rate by measurement or simulation when the flow rate of the second oil-containing fluid flowing in the second pipeline under the first condition is defined as the second recovery flow rate; The process of determining the first opening degree of the first flow control valve so that the ratio of the first recovered flow rate to the first discharged flow rate is within a predetermined range; The process of determining the second opening degree of the second flow control valve so that the ratio of the second recovered flow rate to the second discharged flow rate is within a predetermined range; The process of supplying the mixed fluid to the plurality of bearings using the mixed fluid supply device; The process of operating the recovery device while the opening degree of the first flow control valve is set to the first opening degree and the opening degree of the second flow control valve is set to the second opening degree; and The process of machining the workpiece by means of the cutting tool held in the rotating body and rotating about the first axis. The machine tool also includes multiple pipes, including a first pipe that fluidly connects the first recovery channel to the first ejector, and a second pipe that fluidly connects the second recovery channel to the second ejector. Under the first condition that the plurality of pipes are respectively fluidly connected to the plurality of recovery channels, and the mixed fluid is supplied at a first flow rate from the mixed fluid supply device to the plurality of bearings, the flow rate of the first oil-containing fluid flowing in the first pipe is defined as the first recovery flow rate. Under the second condition, which differs from the first condition in that only the plurality of pipes are fluidly separated from the plurality of recovery channels, the flow rate of the first oil-containing fluid discharged from the first recovery channel to the outside of the first recovery channel is defined as the first discharge flow rate. The opening of the first flow control valve is set such that the first recovery flow rate is within a range of more than 1 and less than 1.5 times the first discharge flow rate. Under the first condition, the flow rate of the second oil-containing fluid flowing in the second pipe is defined as the second recovery flow rate, and under the second condition, the flow rate of the second oil-containing fluid discharged from the second recovery channel to the outside of the second recovery channel is defined as the second discharge flow rate, and the opening of the second flow control valve is set such that the second recovery flow rate is within a range of more than 1 and less than 1.5 times the second discharge flow rate.

12. The method of using the machine tool according to claim 11, wherein, The process of operating the recovery device includes recovering a third oil-containing fluid, which was not recovered by the first recovery channel but passed through the first bearing, via a third recovery channel. The processing steps for the workpiece are performed under the following conditions: The state of supplying a fourth type of air to the air supply channel provided in the housing. A portion of the fourth air is ejected as an air curtain from an air jet port formed between the front end of the rotating body and the housing. The flow rate of the fourth air supplied to the air supply channel is greater than the flow rate of the air ejected from the air jet.

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