JP2002028838A - Main spindle cooling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problems of a conventional method for cooling a conventional main spindle direct, wherein the need of many passages in uniform cooling of the main spindle makes the passages complicate and difficult to manufacture, makes cutting oil difficult to prevent from leaking through joints between the passages, and can not preclude the possibility of an intrusion of the cutting oil into a bearing part. SOLUTION: In a main spindle device comprising a rotatably journaled main spindle, a main spindle cooling device has a passage defined between a cylindrical member disposed in the main spindle and the internal wall of the main spindle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling device for a spindle and a fluid guide device for supplying cutting oil to a tool.

[0002]

2. Description of the Related Art In a machine tool having a main spindle and a housing for accommodating the main spindle, and performing machining by rotating the main spindle in the housing, the spindle heat becomes high due to frictional heat generated by the rotation of the main spindle, which greatly affects machining accuracy. give. In such a machine tool requiring precise machining, how to remove the frictional heat to cool the machine tool is a major problem. In particular, in a built-in type spindle device in which a motor is built in a housing which is a storage portion of the spindle, it is general that a stator is disposed on the spindle in the housing portion of the spindle. Therefore, there is a problem in that the heat generated by the motor is added to the frictional heat generated by the rotation, and the temperature of the spindle becomes higher. As a general method of removing this heat, a method of cooling the housing from the outside (referred to as a representative example 1),
Alternatively, a flow path is formed so as to extend in the longitudinal direction of the main shaft along the center axis direction of the main shaft to cool the main shaft from the inside (see Japanese Patent No. 2510621).
It has been known.

[0003] Representative examples 1 and 2 will be briefly described below. In the method of the first representative example, a flow path (for example, a spiral flow path) provided on the outer surface of the housing of the machine tool is used. The machine tool is provided with a cooling unit (cooling liquid source) as an external oil supply pump for supplying a refrigerant. Both ends of the flow path are connected to the cooling unit through pipes, and the main shaft is indirectly cooled from the outside by circulating a coolant in the flow path to cool the housing. On the other hand, Patent 25106
In the method of the representative example 2 such as No. 21, a flow path formed so as to extend in the main shaft of the machine tool in the longitudinal direction along the center axis direction of the main shaft is used. Further, the flow path is connected to the cooling unit (coolant source). The main shaft is directly cooled by circulating a coolant from the cooling unit. The above is a typical example of a conventional method for cooling the main shaft portion by removing heat generated in the main shaft portion.

[0004] Further, not only the apparatus of the first or second example, but also a machine tool in general, when a tool cuts a workpiece, a lubricating material is required to achieve good lubrication between the tool and the workpiece. Is generally supplied. For this purpose, a pipe for supplying the cutting oil is provided beside the tool and the cutting oil is supplied through this pipe, or a flow path is formed in the tool along the central axis of the tool, and the cutting oil is supplied therefrom. Is supplied (referred to as a representative example 3). In addition, these are for cooling the tool and the object to be processed, and are not intended to cool the main spindle as in the first or second typical example. Here, the representative example 3 will be particularly described.

In the case of the representative example 3, a flow path is formed in the tool along the center axis of the tool. The flow path is formed so as to penetrate from the tip of the tool to a so-called pull stud portion to which the tool is attached. In order to hold such a tool in the main shaft, a long rod called a drawbar is arranged in the main shaft. At the end of the drawbar, a collet, which is a member for holding the pull stud part of the tool, is attached so that it can be opened and closed.The collet opens and closes when the drawbar slides, and holds the pull stud part. And hold the tool. Here, in the case of the representative example 3, a cutting oil flow path penetrating from the one end to the other end of the drawbar is formed in the center of the drawbar along the central axis.
Further, a pump for supplying cutting oil (hereinafter referred to as a pump for through coolant) is provided at the rear end side of the main shaft of the machine tool. Since the spindle and drawbar rotate during machining,
A rotary joint is attached to one end of the draw bar on the side where the pump for through coolant is provided,
Cutting oil can be supplied to the drawbar even during rotation. On the other hand, the outlet of the flow path for cutting oil at the tool side end of the drawbar is almost in contact with the pull stud portion of the tool. Therefore,
In the representative example 3, the cutting oil supplied from the through coolant pump is guided to the cutting oil flow path in the drawbar via the rotary joint, and is supplied to the workpiece from the tool tip through the cutting oil flow path in the tool. You.

[0006] In the technical field of the present invention, the cutting oil is used to cool the object to be machined during machining by improving the lubrication of the tool. Furthermore, the cutting oil also serves the purpose of cooling the device, and it is common to use both as materials without distinction. Therefore, in the present specification, "cutting oil" is used as a word meaning not only "cutting oil" as a general meaning but also "coolant".

[0007]

The conventional apparatus has the following problems. (1) In the conventional method of cooling the housing from the outside (the representative example 1), the housing portion in which the main spindle to be cooled is stored can be maintained at an appropriate temperature by cooling, but the main spindle itself cannot be directly cooled, so that the temperature of the main spindle becomes lower. To rise. Because of this,
Since the main shaft is thermally expanded so as to extend in the longitudinal direction with respect to the housing portion due to a rise in temperature, accuracy in the main shaft longitudinal direction at the time of machining varies. When processing is performed in such a state, the accuracy of the processed product becomes poor. (2) Conventional method of directly cooling the spindle (Representative Example 2)
However, in order to uniformly cool the main shaft, many longitudinal flow paths are required, but the flow paths are complicated and manufacturing is difficult. Further, since the flow path is complicated, there is a possibility that cutting oil may enter the bearing portion from a joint between the flow paths, and it is not easy to prevent this. (3) Conventional method of directly cooling the spindle (Representative Example 2)
In the method of providing a flow path in the main shaft as described above, it is advantageous to take a larger cooling area for each flow path in order to perform efficient cooling. For example, a spiral flow path is advantageous for increasing the contact area with the refrigerant. However, it is not possible to form a spiral flow path, and the flow path to be drilled is naturally limited to a shape extending in the longitudinal direction of the main shaft due to the limitation in machining. (4) Cutting oil used to cut a workpiece while discharging cutting oil from the tip of a tool at the time of machining as in the above-mentioned representative example 3 and used for cooling the spindle as in the representative example 1 or 2. It is common that the same refrigerant is not the same oil, but since all oils have the effect of depriving heat,
When the cutting oil is supplied from the tip of the tool, it is efficient if the cutting oil can be used at the time of cooling the spindle until the cutting oil is supplied. That is, by combining the apparatus of the representative example 2 and the apparatus of the representative example 3 and taking measures to cool the spindle when supplying the cutting oil from the draw bar to the tool tip, the spindle controlled by the temperature-controlled cutting oil can be used. Cooling is convenient.
Further, it is more convenient to provide a low-pressure pump main shaft cooling pump as another pump for performing only cooling of the main shaft in addition to the through-clant pump which is a high-pressure pump so that the pump can be arbitrarily switched. (5) Further, even in the case where the representative example 2 and the representative example 3 are combined as in the case of the above (4), it is convenient if a tool having no cutting oil flow path therein can be used. It is. However, in this case, the purpose of supplying the cutting oil from the tool tip is lost, but in order to achieve the purpose of cooling the main spindle, a tool having a cutting oil flow path therein and a tool not having the cutting oil flow path are provided. In the case of a tool that does not have a cutting oil flow path, a branch discharge flow path that can branch off from the cutting oil flow path in the drawbar near the tool to the spindle side and discharge it It needs to be provided. In such a case, it is particularly convenient if the flow path can be automatically switched according to the attached tool in each of the case where the tool has a cutting oil flow path and the case where the cutting oil flow path is not provided. It is. (6) Further, even in the case where the representative example 2 and the representative example 3 are used in combination in common as in the case of the above (4), a tool in which a cutting oil flow path is disposed is used. In such a case, when actually performing machining, the cutting oil liquid is discharged from the tip of the tool, and during machining suspension (when the spindle is rotating but the tool is not machining), the branch discharge flow path is used. It is convenient for use if the flow path through which the cutting oil flows can be arbitrarily switched so that the cutting oil can be discharged.
In such a case, it is particularly convenient if the flow path can be automatically switched by switching between the through coolant pump and the spindle cooling pump.

[0008]

According to the present invention, there is provided a spindle device including a spindle rotatably supported by a shaft, wherein a cutting oil flow path is formed between the inner wall of the spindle and a member abutting on the inner wall of the spindle. A spindle cooling device, characterized in that the member is a cylindrical member disposed inside the spindle so as to enclose the drawbar, and the cutting oil flow path is a cutting member drilled in the shaft of the drawbar. A spindle cooling device characterized by being connected to an oil flow path is provided to solve the problems ((1) to (3)) to be solved in the conventional technology. With this, a flow path can be formed by providing a cylindrical member as a member that comes into contact with the main shaft inner wall and forming a groove in at least one of the cylindrical member outer surface and the main shaft inner wall. Is not limited to being formed in the longitudinal direction, and a free shape can be selected. Further, the flow path is simplified by flowing the cutting oil in the radial direction, so that the joint of these flow paths can be easily sealed. Since a cylindrical member is provided as a member that comes into contact with the main spindle inner wall, and a groove can be formed in at least one of the cylindrical member outer surface and the main spindle inner wall, a flow path can be formed. It is not limited to drilling in the direction, and a free shape can be selected. Further, the present invention provides a spindle cooling device, wherein the cutting oil flow path is a spiral flow path. By using the cylindrical member, a flow path can be formed spirally around the central axis of the main shaft, and the contact length between the cutting oil and the main shaft can be increased.

Further, a tool having a pull stud having a constricted portion at an end portion, a main shaft having a central axis and rotatably supported around the central axis, and a central shaft disposed inside the main shaft. A pipe having a first hole slidable in a direction along the axis and capable of holding the constricted portion, a first hole extending in a direction along the central axis, and a flange provided at an end of the pipe. A spindle device including an actuator member, a cylindrical portion having a first cross-section, and a piston having a second cross-section and having a rod-shaped portion having a second cross-section and extending in an elongated direction along the central axis direction from the cylindrical portion. Wherein the main shaft has a second cutting oil flow path perforated so as to extend radially outward from an inner surface near an end thereof and then extend in a direction of the central axis near the tip, and the drawbar includes: Seventh cutting oil flow path extending along the central axis A fourth cutting oil flow path that is drilled so as to penetrate in a radial direction from the seventh cutting oil flow path to the outer peripheral surface of the drawbar, and a part of the seventh cutting oil flow path is The piston has a large-diameter recess, and the piston has a pipe extending at an end of the cylindrical section from the end face thereof in a direction along the central axis, and a pipe extending radially therethrough from the end to the outer periphery. An eighth cutting oil passage having the following. The pipe of the actuator member is fitted into the seventh cutting oil passage, and the flange surface of the actuator member contacts the end surface of the pull stud via a sealing material. A second hole that penetrates the inside and outside of the pipe and is connected to the recess on the side surface of the pipe of the actuator member, and the end of the piston on the cylindrical portion side is inserted into the seventh cutting oil flow path. The piston is slidable along the seventh cutting oil flow path, The rod-shaped portion side is fitted in the first hole, and forms a ninth cutting oil flow path with a gap generated between the first hole and the first cross section. When a first cutting oil flow path extending from the end face of the pull stud is provided in the tool, the rod portion is fitted into the first cutting oil flow path, and the eighth cutting oil flow path is connected to the fourth cutting oil flow path. While blocking the oil flow path, the seventh cutting oil flow path, the eighth cutting oil flow path, the depression, the ninth cutting oil flow path, and the first cutting oil flow path are connected, and the When the first cutting oil flow path is not provided, the rod-shaped portion contacts the end face of the pull stud, the second cutting oil flow path is cut off from the recess, and the seventh cutting oil flow path is provided. And the eighth cutting oil flow path, and the fluid guiding device, wherein the fourth cutting oil flow path and the second cutting oil flow path are connected to each other. In other words, when using a tool that does not have a flow path in the tool itself by this device, only the spindle cooling pump is operated to discharge cutting oil from portions other than the tool, while a flow path is provided inside. When using a tool that has the same function, it is possible to change the flow path corresponding to each by operating the pump for through coolant, and the tool itself has a flow path, and the cutting oil is discharged from the tip of the tool during machining In addition, there is an effect that the apparatus can be shared in both a mode in which the processing of the processing target is processed and a mode in which processing is performed using a tool having no flow path provided in the tool itself.

Further, according to the present invention, a first cutting oil flow path for supplying cutting oil to the tool tip, a second cutting oil flow path formed in the main shaft bypassing the first cutting oil flow path, A piston member provided in the main shaft and having a third cutting oil flow path therein, and when the cutting oil supplied from the drawbar flows at the first pressure, the piston does not move and the third cutting oil flow path is The fluid guide device is connected to the second cutting oil flow path, and the piston moves when the cutting oil flows at the second pressure, and the third cutting oil flow path is connected to the first cutting oil flow path. . This allows the through-coolant pump to operate to discharge the cutting oil from the tool tip during actual machining, and the spindle cooling pump to be turned off when the machining is paused. By switching to, cutting oil can be discharged from portions other than the tool. Therefore, even when using a tool with a flow path inside in a device that can be shared with any tool regardless of whether or not a flow path is placed inside, even when a tool is actually machined, Discharges cutting fluid, and the tool is rotating but does not process the workpiece. The flow path can be easily switched automatically according to the processing so as to discharge the cutting oil.

[0011]

(Embodiment 1) FIGS. 1 and 2 show an embodiment.
This will be described with reference to FIG. FIG. 1 shows a spindle device to which the cooling device of the present invention is applied, and FIG. 2 is an enlarged view of the vicinity of the spindle 1. As shown in FIG. 1, a housing 1 serving as a spindle housing portion is provided.
The main shaft 1 is supported by bearings 13 and 14 in 0. The stator 2 is provided inside the housing 10.
A rotor 3 is arranged facing the main shaft 1. Spindle 1
In a hollow state, a drawbar B8 is arranged in the hollow part. Further, a cylindrical member 5 is disposed between the drawbar B 8 and the main shaft 1 substantially at the position of the rotor 3. The outer surface of the cylindrical member 5 is in contact with the inner surface of the main shaft 1, while the inner surface of the cylindrical member 5 is in contact with the outer surface of the drawbar B8. The drawbar B 8 is screwed at its tip end to a drawbar A 7 containing a piston 9 therein.
Therefore, the drawbar A7 and the drawbar B8 slide integrally inside the main shaft 1. Drawbar A 7
A means for holding the pull stud 34 of the tool 35 is attached to the tip of the tool 35. When the drawbar A7 slides together with the drawbar B8, the means moves in the direction of the central axis according to the shape of the inner wall of the main shaft 1, and grips the pull stud 34 of the tool holder 35 on which the tool 36 is mounted. Inside the drawbar A7 attached to the drawbar B8 by screw fitting, a piston 9 having a shape elongated from a cylinder and having a pipe portion protruding is arranged. The diameter of the cylindrical portion of the piston 9 is substantially the same within a slidable range while being slightly smaller than the radius of the flow path cross section inside the drawbar A7, while the pipe portion is thinner than the cylindrical portion.
The cylindrical portion of the piston 9 is slidable along the center axis of the drawbar along the inner wall of the drawbar A7. A step is provided inside the drawbar A7 which is closer to the tool than the piston 9, and a spring 11 is mounted between the step and the end face of the piston 9 which is closer to the tool. The spring 11 is provided so as to include the pipe portion of the piston 9. Due to the spring 11, the piston 9 is always on the drawbar B8 side (the side opposite to the tool) with respect to the drawbar A7.
Is being biased toward. Since the cutting oil is supplied from a through-clant pump provided on the side opposite to the tool 36, the cutting oil is urged in the direction opposite to the direction in which the cutting oil flows. Therefore, when the cutting oil is flowing, the piston 9 tries to move against the spring force by the cutting oil, while when the cutting oil is not flowing, the piston 9 is pushed to the side opposite to the tool by the spring force.

Next, the flow path provided in the apparatus will be described. A spiral flow path 16 is provided outside the housing 10 as a cooling flow path outside the main shaft.
3 and channels 15 and 17. on the other hand,
The cooling channels inside the spindle are as follows. A flow path 20 and a flow path 26 are formed in the axial center of the drawbar B8. Among them, the flow path 20 is provided with a cooling pump 31 and a through coolant pump 3 via a temperature controller 30.
2 are connected. This through coolant pump 3
Numeral 2 allows the cutting oil to flow at a higher pressure than the spindle cooling pump 31. Since the drawbar B8 rotates together with the main shaft, a rotary joint 29 is provided between the temperature controller 30 and the flow path 20 so that cutting oil does not leak even during rotation. As shown in FIG. 2, a cylindrical member 5 is arranged on the main shaft 1 so as to contact an inner wall surface thereof. A spiral groove 6 is provided on the outer peripheral portion of the cylindrical member 5.
Are provided, and a spiral flow path is formed by the spiral groove 6 and the inner wall surface. At both ends of the spiral groove 6, radial passages 23 and 24 connected to the inner surface of the cylindrical member 5 near both ends of the cylindrical member 5 are connected. On the other hand, a flow path 22 and a flow path 25 extending in the radial direction from the axis of the draw bar B 8 to the outer peripheral portion of the draw bar B 8 are arranged in the draw bar B 8. The flow path 20 provided on the shaft center is
Is connected to On the other hand, from the point where the flow path 25 intersects with the drawbar B8, the flow path 2 extends along the axis of the drawbar B8.
6 are provided. That is, the flow path 20 and the flow path 26 are connected to the flow path 22 and the flow path 25, respectively. Further, points (holes) at which the flow path 22 and the flow path 25 emerge on the outer peripheral portion of the drawbar B8 correspond to the flow path 23 and the flow path 24, respectively. That is, the flow path 22 and the flow path 25 are connected to the flow path 23 and the flow path 24, respectively. As a result, the flow path 20, the flow path 22, the flow path 23, the spiral groove 6, the flow path 24, the flow path 25, and the flow path 26 form a continuous flow path in this order.

Next, the flow path inside the piston 9 will be described with reference to FIG. FIG. 3 is an enlarged view of the vicinity of the piston 9 in FIG. As shown in FIG.
Are provided with a flow path 27 and a flow path 39 which are flow paths in the axial direction, and are connected to flow paths 37 and 38 in the radial direction, respectively. The flow path 39 forms a flow path in the pipe portion of the piston 9. Here, the end of the flow path 27 and the flow path 3
7 to form a fifth cutting oil flow path,
And the flow path 38 are combined to form a sixth cutting oil flow path. On the other hand, a drawbar A7 including the piston 9 is provided with a flow path 41 which is a fourth cutting oil flowpath extending in the radial direction from the inner surface to the outer surface of the drawbar A7. In addition, the main shaft 1 extends radially outward from the inner surface of the main shaft and then extends along the central axis of the main shaft 1 as a second cutting oil flow passage 43.
Is provided. When the drawbar is holding the pull stud, the flow path 41 as the fourth cutting oil flow path and the flow path 43 as the second cutting oil flow path are connected to each other. Further, a recess 4 is provided in the flow path inside the drawbar A7.
2 are provided. The width of the concave portion 42 in the direction along the center axis of the drawbar is equal to or greater than the distance between the closest points of the respective outer peripheral portions of the flow channel 37 and the flow channel 38, and The path 38 and the depression 42 are connected at the same time. Since the depression 42 is used as a flow path, if the distance between the farthest points of the respective outer peripheral portions can be made larger, a larger flow path cross section can be secured, which is effective. . The distance between the recess 42 and the flow path 41 is determined by the point of the flow path 37 when the piston 9 is most separated from the tool by the biasing force of the spring 11, and the point where the piston 9 comes closest to the tool against the spring force. Is shorter than the distance. However, the distance between the recess 42 and the flow path 41 is larger than the diameter of the flow path 37 so that the flow path 37 does not cover both the recess 42 and the flow path 41 at the same time. A flow path 44 is provided in the axis of the pull stud 34 attached to the main shaft 1, and is connected to a flow path in a tool 36 via a tool holder 35.

How the cutting oil in the flow passage cools the main shaft 1 by the flow passage in the main shaft having the above structure will be described below. First, cooling of the stator 2 will be described. The cutting oil is supplied from the cooling unit 33 to the spiral flow path 16 of the housing 10 through the flow path 15, and the flow of the cutting oil is returned to the cooling unit 33 by the flow path 17 so that the vicinity of the stator 2 is cooled. Cooling. Next, the rotor 3
The cooling in the vicinity will be described. The cutting oil is supplied to the temperature controller 30 by the spindle cooling pump 31. The cutting oil controlled to an appropriate temperature by the temperature controller 30 flows through the flow path 20 and the axis of the drawbar B8 toward the tool 36. Further, the cutting oil flows in a radial direction through a flow path 22 connected to the flow path 20 and is guided to a flow path 23 provided in the cylindrical member 5. The cutting oil guided to the outer surface of the cylindrical member by the flow path 23 cools the rotor 3 while contacting the outer surface of the cylindrical member 5 by the spiral groove 6. The cutting oil from which the heat of the rotor has been removed is further passed through the flow path 24 and the flow path 25 to the draw bar B 8.
Is drawn back to the axis of
8 flows in the direction of the tool holder 35. Drawbar B
The cutting oil guided from the flow path 26 of 8 flows into the flow path 27 of the piston 9 and is guided radially outward by the flow path 37.
The cutting oil guided to the flow path 37 is discharged from the flow path 41 provided in the drawbar A7 through the cutting oil discharge path 43 from the end of the main spindle 1. The cutting oil discharged from the cutting oil discharge path 43 returns to the spindle cooling pump 31 via the return path 45.

In the first embodiment shown in FIGS. 1 to 4, a groove is provided on the outer peripheral portion of the cylindrical member 5. However, as another embodiment, as shown in FIG. Can be provided on the inner wall surface of the vehicle. Alternatively, the same effect as that of the above embodiment can be obtained by providing both the cylindrical member 5 and the inner wall surface of the main shaft 1. Further, as another embodiment, as shown in FIG. 6, a part of the draw bar B8 is made thicker to make contact with the main shaft 1, and after the function of the cylindrical member 5 is provided, a groove 6 is formed in the inner wall of the main shaft 1. The same effect as that of the first embodiment can be obtained by providing.

(Embodiment 2) Next, referring to FIGS. 3 and 4, the cutting oil cooled in the vicinity of the rotor 3 is supplied to the passage 43 as a second cutting oil passage or to the tip of the tool. The operation of the piston 9 which is a switching device for supplying will be described. At the time of cooling of the portion near the rotor 3, the cutting oil is circulated using the spindle cooling pump 31 at the time of non-machining. At this time, the piston 9 is almost in contact with the drawbar A7 as shown in FIG. The flow path 37 as the fifth cutting oil flow path is connected to the flow path 41 as the fourth cutting oil flow path. On the other hand, at this position, the flow path 38 as the sixth cutting oil flow path is closed by the inner wall of the drawbar A7. Therefore, the cutting oil supplied from the flow path 26 as the third cutting oil flow path in the drawbar B 8 flows from the flow path 27 to the flow path 43 via the flow paths 37 and 41, while the sixth cutting oil flow path It does not flow to the side of the channel 38 and the channel 39. When supplying cutting oil from the tool tip, the through coolant pump 32 is operated. The cutting oil flows to the outlet of the flow path 26 of the drawbar B8 in the same manner as in the case shown in FIG. However, since the through-coolant pump 32 has a high discharge pressure, the pressure received by the piston 9 is higher than during operation of the spindle cooling pump. Therefore, the space 40 is filled with the cutting oil, and the piston 9 urged toward the drawbar B 8 by the pressure received from the cutting oil moves to the tool side as shown in FIG. As a result, the flow path 37 connected to the flow path 41 is separated from the flow path 41 and newly connected to the recess 42. Further, since the concave portion 42 serves to connect the flow path 37 and the flow path 38, the depression 42 is connected to the flow path 44 as the first cutting oil flow path in the pull stud 34 via the flow path 39, and the flow path 41 is Nine walls are closed. Accordingly, the cutting oil supplied from the outlet of the flow path 26 of the drawbar B8 passes through the flow path 27 from the space 40, and is supplied to the tool tip from the flow path 44 via the flow path 37, the recess 42, and the flow path 38. Is done. The cutting oil discharged from the tip of the tool 36 returns to the through coolant pump 32 via the return path 45. Since the piston 9 is biased toward the drawbar B8 by the spring 11, if the operation of the through coolant pump 32 is stopped and the operation is switched to the main shaft cooling pump 31, the pressure of the cutting oil is reduced, and the piston 9 returns to its original state. Return to channel 3
7 is connected to the flow path 41, and the supply of cutting oil to the tip of the tool is stopped.

The radial flow paths 37 and 38 provided in the piston 9, the radial flow paths 22 and 25 provided in the drawbar B 8, and the drawbar A
The radial flow path 27 provided in 7 can be provided as a plurality of flow paths as long as the cross-sectional area of the portion where the flow path is provided does not decrease in strength.

At the time of assembling the apparatus, it is not easy to match the positions of the flow paths 23 and 24 provided in the cylindrical member 5 with the positions of the flow paths 22 and 25 provided in the drawbar B8. Therefore, a concave portion 46 is provided in the flow path 23 and the flow path 24 so that even if the relative position between the cylindrical member 5 and the drawbar B8 slightly shifts, these flow paths can be easily performed without requiring precise alignment. The road can be positioned. In addition, the recess 42 may be constituted by several channels in which a longitudinal hole is engraved in the main axis direction. However, if the recess 42 is provided in the entire circumferential direction, the circumference of the piston 9 in the movement of the piston 9 is increased. This is advantageous in that the joining between the flow path 37 and the flow path 38 can be easily and always ensured without making the relative position in the direction a problem.

Although the first embodiment has been described as an example of application to a built-in type spindle device having a rotor on the main shaft and a stator in the housing, the same applies to a non-build-in type spindle device having no stator and rotor in the housing. It can be applied in a configuration. In that case,
What is necessary is just to arrange | position and arrange | position a cylindrical member in the to-be-cooled part of a spindle like Example 1 above.

(Embodiment 3) Subsequently, FIGS. 7A and 7B
, When the tool 35 includes the flow path 44, the flow path 44 is used, and when the tool 35 does not include the flow path 44, the flow path 43 provided in the main shaft is switched. A third embodiment will be described. Here, FIG. 7A shows the application of the third embodiment when the tool 35 has the flow path 44 inside, and FIG. 7B shows the application of the third embodiment when the tool 35 does not have the flow path 44 inside. It is. First, the configuration of the third embodiment will be described with reference to FIGS. 7A and 7B. A drawbar B 8 is disposed inside the main shaft 1. The draw bar B 8 is slidable along the central axis of the main shaft, and has a flow path 26 extending along the central axis at the central shaft portion. Is the same as in the second embodiment.
Drawbar B 8 is screwed into drawbar A 7. On the other hand, in the drawbar A7, a drawbar C50 is screwed on the opposite side of the drawbar B8, so that the drawbar A7 and the drawbar C50 have an integrated structure so as to form a part of the drawbar B8. Has become. Drawbar A
7 is included in the main shaft 1 so as to contact the inner surface of the main shaft 1. The main spindle 1 is provided with a flow path 43 that extends radially outward from an inner surface that is in contact with the drawbar A7 and then extends in a direction along the central axis of the main spindle 1 as a second cutting oil flow path.
The drawbar A 7 has a flow path 61 extending through the center axis and a flow path 41 as a fourth cutting oil flow path penetrating in a radial direction from the inner surface of the flow path 61 to the outer periphery of the drawbar A 7. ing. The flow channel 61 has a counterbore-shaped recess 62 and a recess 63 having different cross sections. A hole 54 is provided in the center axis of the drawbar C50. Hole 54
, The flow path 61 and the flow path 26 constitute a seventh cutting oil flow path in the integrated drawbar. An actuator member 55 and a piston 59 are arranged inside the drawbar C50. The actuator member 55 is a member that includes an elongated pipe 67 having a hole 64 therein and a flange 56 having a seal member 60 on an end surface. The piston 59 has a cylindrical portion 66 and a rod-like portion 65 that is elongated from the cylindrical portion 66. The cross section of the rod-shaped portion 65 has a polygonal shape. In this embodiment, a triangle is assumed as a representative example of the polygon. The cylindrical portion 66 of the piston 59 has a size that fits into the flow channel 61. The cross-sectional radius of the cylindrical portion 66 and the outer shape of the pipe 67 are almost the same size.
The pipe 67 is provided with a hole 53. The hole 53 is connected to the depression 63 when the actuator member 55 is arranged at a predetermined position. The cylindrical portion 66 has a flow path 47 extending from the end of the cylindrical portion 66 along the central axis.
And a flow path 57 extending radially outward from the end of the cylindrical part and reaching the outer peripheral surface of the cylindrical portion, and constitutes an eighth cutting oil flow path. The pipe 67 of the actuator member 55 is fitted into the hole 54 of the drawbar C50 from the outside to the inside until it penetrates the drawbar C50. The rod portion 65 of the piston 59 is inserted into the hole 64 from the inside of the drawbar B8 and the drawbar C50. When inserted, each vertex of the triangle of the cross section comes into contact with the inner surface of the hole 64, and the rod-shaped portion 65 is stably held in the hole 64. Also, due to the difference in the cross-sectional shape between the hole 64 and the rod portion 65, a ninth cutting oil flow path is secured in the hole 64 even when the rod portion 65 is inserted. The disk-shaped collar 51 is fixed to the outer periphery of the pipe 67 of the actuator member 55 so as not to move in the center axis direction with respect to the pipe 67. The collar 51 is arranged so that the plane of the collar 51 is perpendicular to the center axis of the pipe. A spring 52 is fitted between the stepped portion of the concave portion 62 of the drawbar A 7 and the collar 51. The actuator member 55 is always urged in the tool direction by the spring 52 and the collar 51. As a result, the flange 56 of the actuator member 55 is firmly pressed against the pull stud 34, and the sealing effect provided by the seal member 60 provided on the flange 55 increases. A protrusion 58 is provided on the tool 35 side of the drawbar C 50, and a claw 68 extending radially outward from the protrusion 58 is provided at a tip of the protrusion 58. The projection 58 is provided with a collet 69. The collet 69 is made up of components divided in the circumferential direction. The constituent member of the collet 69 is provided with a key-like portion 69d at the base portion, and the key-like portion 69d is engaged with the claw 68. On the distal end side of the collet 69, a claw 69c protruding toward the inner surface is provided. Further, on the side where the collet 69 is in contact with the main shaft 1, there are provided a slope 69 configured to move away from the main shaft as approaching the tool 35 side, and a projection 69 b protruding outward from the main shaft 1.

Next, referring to FIGS. 7A and 7B, the case where the tool 35 has a flow path 44 as a first cutting oil flow path inside, and the case where the tool 35 has a flow path 44 therein. A description will be given of how the device according to the third embodiment operates when there is no device. 7A and 7B, the collet 69 opens and closes by sliding the drawbar B8. In the state of FIG. 7, the collet is closed, but when the drawbar B 8 is slid to the tool 35 side, the outer projection 69 b of the collet 69 moves outward along the recess 1 a of the main shaft 1, The key portion 69d at the base of the collet 69 moves so as to come into contact with the protrusion 58 of the drawbar C50, and the constituent members of the collet 69 are opened. At this time, the outer inclined surface 69a of the collet 69 comes into contact with the inner surface of the main shaft. Conversely, from this state, drawbar B 8 is used for tool 3
When the slide is moved away from the fifth side, the projection 69b of the collet 69 moves so as to return inside from the recess 1a of the main shaft 1, and the collet 69 closes. At this time, the claws 69c on the inner surface of the collet 69 hold the constricted portion 34a of the pull stud 34 and grip the tool 35. First, a case where the flow path 44 is provided in the tool 35 as shown in FIG. 7A will be described.
When the pull stud 34 is retracted by the collet 69 and the end face of the pull stud 34 comes into contact with the surface of the actuator member 55, the rod-shaped portion 65 of the piston 59 is fitted into the flow path 44 as the first cutting oil flow path. Here, when the cutting oil pressurized by the through coolant pump 32 shown in FIG. 1 is supplied through the flow path 26 and the flow path 61 of the drawbar A as the seventh cutting oil flow path, the cutting oil It is guided to a flow path 47 and a flow path 57 which are cutting oil flow paths. At this time, the flow path 5
Pressing the wall surface when the cutting oil bends in step 7 allows the cylindrical portion 66
Is pushed, and the piston 59 moves to the tool 35 side. The moved piston 59 has a cylindrical portion 66 formed by the actuator member 5.
5 comes in contact with the wall surface of the pipe 67 and stops. At this time, the flow path 57 as the eighth cutting oil flow path is not connected to the flow path 41 as the fourth cutting oil flow path. On the other hand, in this state, the flow path 57 is connected to the depression 62. The cutting oil guided to the flow path 57 exits from the cylindrical portion and enters the concave portion 62, and the actuator member 5
5 through the hole 53 formed in the pipe 67 and the hole 6
The tool 3 is guided to a flow path 44 as a first cutting oil flow path of the pull stud 34 through a ninth cutting oil flow path secured in the tool 4.
Flows to 6. Next, a case will be described in which the flow path 44 as the first cutting oil flow path is not provided in the tool 35 as shown in FIG. 7B. The pull stud 34 is retracted by the collet 69 and the end face of the pull stud 34 is
, The rod 65 of the piston 59 is pushed into the drawbar toward the side opposite to the tool. At this time, the flow path 47 and the flow path 57 as the eighth cutting oil flow path are connected to the flow path 41 as the fourth cutting oil flow path, and the flow path 41 as the fourth flow path is a flow path 43 as the second cutting oil flow path. Leads to. Here, when the cutting oil pressurized by the spindle cooling pump 31 is supplied from the flow path 26 of the drawbar B8, the cutting oil is supplied to the flow path 4
7 to the flow path 57. The cutting oil guided to the flow path 57 is discharged from the end face of the main shaft 1 through the flow path 41 and the flow path 43. At this time, since the rod-shaped portion 65 hits the end face of the pull stud, it cannot move, and a flow path from the flow path 57 to the flow path 43 via the flow path 41 is secured. As described above, when the tool 35 has the flow path 44 therein, the flow path 44 is used. When the tool 35 does not have the flow path 44 inside, the flow path 43 provided in the main shaft is used. Can be easily switched as described above. In the above case, both the through-coolant pump 32, which is a relatively high-pressure pump, and the spindle cooling pump, which is a relatively low-pressure pump, are provided at the end of the main shaft 1 opposite to the tool 35. In addition, the cutting oil flows from both pumps to the flow path 26. When the flow path 44 as the first cutting oil flow path is provided in the tool, the through coolant pump 32 is used, and when the tool does not have the flow path 44, the spindle cooling pump is used. Can be switched as follows.

[0022]

According to the present invention, since the spindle is cooled from the inside with a simple configuration, thermal expansion of the spindle can be prevented, and the processing accuracy by the device can be improved.
The present invention has a structure in which the flow path required for cooling is simple and there is no possibility that cutting oil may enter the bearing portion. Further, in the present invention, by switching the flow path by the piston member, it becomes easy to use the cutting oil for cooling the main shaft, and further, it is possible to easily switch the flow path at the time of machining or non-machining. Further, according to the present invention, it is possible to easily switch the flow path between the case where the flow path is provided inside the tool and the case where the flow path is not provided.

[Brief description of the drawings]

FIG. 1 is a sectional view of a spindle device to which the present invention is applied.

FIG. 2 is an enlarged view of a main shaft portion according to the first or second embodiment.

FIG. 3 is an enlarged view of a piston portion in FIGS. 1 and 2, and shows a behavior of the piston during non-machining.

FIG. 4 is an enlarged view of a piston portion in FIGS. 1 and 2, showing the behavior of the piston during machining.

FIG. 5 is an enlarged view of a main shaft portion according to the first or second embodiment.

FIG. 6 is an enlarged view of a main shaft portion according to the first or second embodiment.

FIG. 7A is an enlarged view of a main shaft portion according to a third embodiment,
This shows an application of the third embodiment in a case where the tool 35 has a flow path 44 therein.

FIG. 7B is an enlarged view of a main shaft portion according to the third embodiment,
This shows an application of the third embodiment when the tool 35 does not have the flow path 44 therein.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main shaft 2 Stator 3 Rotor 5 Cylindrical member 6 Helical groove 7 Drawbar A 8 Drawbar B 9 Piston 10 Housing 13, 14 Bearing 30 Temperature controller 31 Cooling pump 32 Pump for through coolant 33 Cooling unit 35 Tool holder 36 Tool

Claims (11)

[Claims] 1. A spindle cooling device comprising a spindle device rotatably supported by a spindle, wherein a cutting oil flow path is formed between the inner wall of the spindle and a member abutting on the inner wall of the spindle. 2. The spindle cooling device according to claim 1, wherein the cutting oil flow path includes a groove formed in at least one of the member and an inner wall of the spindle. 3. The spindle cooling device according to claim 1, wherein the cutting oil flow path is a spiral flow path. 4. The apparatus according to claim 1, wherein the member is a part of a drawbar, and the cutting oil flow path is connected to a cutting oil flow path drilled in a shaft of the drawbar. Spindle cooling device. 5. The drawbar according to claim 1, wherein the member is a cylindrical member disposed inside the main shaft so as to include the drawbar, and the cutting oil flow path is formed in the shaft of the drawbar. A spindle cooling device, which is connected to a cutting oil flow path. 6. A spindle device including a spindle rotatably supported in a spindle, wherein a first cutting oil flow path for supplying cutting oil to a tool tip, and a drilling hole is formed in the spindle while bypassing the first cutting oil flow path. A second cutting oil flow path provided therein, and a piston provided in the main shaft and having a third cutting oil flow path therein, wherein the piston is provided when cutting oil supplied from the drawbar flows at a first pressure. The third cutting oil flow path is connected to the second cutting oil flow path without moving, and when the cutting oil flows at the second pressure, the piston moves and the third cutting oil flow path becomes the first cutting oil flow path. A fluid guide device characterized by being connected to 7. The method according to claim 4, further comprising: a first cutting oil flow path for supplying cutting oil to a tool tip; and a second drilling hole formed in the main shaft bypassing the first cutting oil flow path. A cutting oil flow path, comprising a piston provided in the main shaft and having a third cutting oil flow path therein, and when the fluid flowing through the spiral flow path flows at a first pressure, the piston does not move. The third cutting oil flow path is connected to the second cutting oil flow path, and when the fluid flows at the second pressure, the piston moves so that the third cutting oil flow path is connected to the first cutting oil flow path. A fluid guide device characterized by the following. 8. The fluid guide device according to claim 6, wherein the piston is urged in a direction opposite to a flow direction of the cutting oil in the third cutting oil flow path. 9. The fluid guide device according to claim 6, further comprising a pump for increasing the first pressure to a second pressure. . 10. A tool having at its end a pull stud having a constricted portion, a main shaft having a central axis and rotatably supported around the central axis, and a central shaft disposed inside the main shaft. A pipe having a first hole slidable in a direction along the axis and capable of holding the constricted portion, a first hole extending in a direction along the central axis, and a flange provided at an end of the pipe. An actuator member, a main shaft device including: a cylindrical portion having a first cross section; and a piston having a second cross section and having a rod-shaped portion elongated from the cylindrical portion along the central axis direction from the cylindrical portion. Wherein the main shaft has a second cutting oil flow passage formed near the tip and extending radially outward from the inner surface and extending in the direction of the central axis near the tip, and the drawbar includes: A seventh cutting oil flow path extending along the central axis; A fourth cutting oil flow path that is drilled so as to penetrate in a radial direction from the seventh cutting oil flow path to the outer peripheral surface of the drawbar, wherein a part of the seventh cutting oil flow path is A recess having a large diameter, wherein the piston has, at an end of the cylindrical portion, a pipe extending inward from the end face thereof in a direction along the central axis, and a pipe penetrating therethrough in a radial direction from the end to an outer peripheral portion. An eighth cutting oil flow path provided, wherein the pipe of the actuator member is fitted into the seventh cutting oil flow path, and a flange surface of the actuator member is in contact with an end surface of the pull stud via a sealing material. A second hole that penetrates the inside and outside of the pipe and is connected to the recessed portion is provided on a side surface of the pipe of the actuator member, and the end of the piston on the cylindrical portion side is fitted into the seventh cutting oil flow path. The piston is slidable along the seventh cutting oil flow path; The rod-shaped portion side is fitted in the first hole, and forms a ninth cutting oil flow path with a gap generated between the first hole and the first cross section. When a first cutting oil flow path extending from the end face of the pull stud is provided in the tool, the rod portion is fitted into the first cutting oil flow path, and the eighth cutting oil flow path is connected to the fourth cutting oil flow path. The oil flow path is shut off, and the seventh cutting oil flow path, the eighth cutting oil flow path, the depression, the ninth cutting oil flow path, and the first cutting oil flow path are connected to each other. When the first cutting oil flow path is not provided, the rod-shaped portion contacts the end face of the pull stud, the second cutting oil flow path is cut off from the recess, and the seventh cutting oil flow path is provided. And the eighth cutting oil flow path, and the fourth cutting oil flow path and the second cutting oil flow path are connected to each other. 11. The tool according to claim 4, further comprising: a tool having a pull stud having a constricted portion at an end thereof; and a tool disposed inside the main shaft and slidable in a direction along a central axis of the main shaft. An actuator member having a drawbar capable of holding the constricted portion, a pipe having a first hole extending in a direction along a central axis of the main shaft, and a flange provided at an end of the pipe; And a piston having a second cross section and a rod having a second cross section and extending elongate from the cylindrical portion along the central axis direction. Wherein the main shaft has a second cutting oil flow passage formed in the vicinity of the distal end so as to extend radially outward from the inner surface and then extend in the central axis direction, and the drawbar extends along the central axis. Seventh cutting oil flow path and the seventh cutting oil flow And a fourth cutting oil flow path drilled so as to penetrate radially from the drawbar to the outer peripheral surface of the drawbar, and a part of the seventh cutting oil flow path has a recess having a diameter larger than its cross section. Eighth cutting, wherein the piston has at the end of the cylindrical portion a pipe extending inward from the end face thereof in a direction along the central axis of the main shaft and a pipe extending radially therethrough from the end face to the outer peripheral portion. An oil passage, wherein the pipe of the actuator member is fitted into the seventh cutting oil passage, a flange surface of the actuator member abuts on an end surface of the pull stud via a sealing material, and the actuator member A second hole which penetrates the inside and outside of the pipe and is connected to the recessed portion is provided on a side surface of the pipe, and an end of the piston on a cylindrical portion side is fitted into the seventh cutting oil flow path, and The piston can slide along the seventh cutting oil flow path, and the piston is rod-shaped. The part side is fitted in the first hole, a ninth cutting oil flow path is formed by a gap generated between the first hole and the first cross section, and the fluid guide device includes the tool When a first cutting oil flow path extending from the end face of the pull stud is provided therein, the rod-shaped portion fits into the first cutting oil flow path, and the eighth cutting oil flow path is connected to the fourth cutting oil flow. And the seventh cutting oil flow path, the eighth cutting oil flow path, the depression, the ninth cutting oil flow path, and the first cutting oil flow path are connected to each other. When one cutting oil flow path is not provided, the rod-shaped portion comes into contact with the end face of the pull stud, the second cutting oil flow path is cut off from the recess, and the seventh cutting oil flow path and the The fluid guiding device, wherein an eighth cutting oil flow path, the fourth cutting oil flow path, and the second cutting oil flow path are connected.