JP3746630B2 - Spindle device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention spindle apparatus installed in a high speed cutting device or grinding device, relates to a spindle apparatus having a combined externally pressurized gas and magnetic bearing assembly especially.
[0002]
[Prior art]
In order to perform high-efficiency and high-precision machining, a spindle device capable of high-speed rotation and high rotation accuracy is required. In response to this requirement, non-contact bearings such as a static pressure gas bearing and a static pressure magnetic composite bearing (for example, Japanese Patent Application No. 10-97505) in which a magnetic bearing is integrated with a static pressure gas bearing are employed. FIG. 9 shows an example of a hydrostatic magnetic compound bearing spindle device.
In the spindle apparatus using these non-contact bearings, as shown in the example of FIG. 9, it is common to have a flange portion 4a on the main shaft 4 and configure an axial bearing surface using both end surfaces of the flange portion 4a. It is.
[0003]
[Problems to be solved by the invention]
In such a hydrostatic gas bearing spindle device and hydrostatic magnetic compound bearing spindle device, as described in the example of FIG. 9, the axial position (C dimension) of the tip of the tool 11 attached to the spindle end is the spindle. It varies depending on the dimension (B dimension) of the housing 5 from the apparatus mounting position P to the spindle flange 4a and the dimension (A dimension) of the spindle 4 from the spindle flange 4a to the tool tip. The housing attachment position P is a position where the housing 5 is attached to the housing installation base 74 that is driven forward and backward by the spindle positioning mechanism 75.
When the hydrostatic gas bearing spindle device or the hydrostatic magnetic compound bearing spindle device is rotated at a high speed, the temperature of the main shaft 4 and the housing 5 rises due to the loss (windage loss) in the hydrostatic gas bearing portion. The axial position (C dimension) of the tool tip changes from the accompanying axial thermal expansion amount. For this reason, the subject that a highly accurate process became difficult occurred.
[0004]
The purpose of this invention, even when change temperature, such as housing, Ru der to provide a spindle device capable of machining a workpiece with high precision.
[0005]
[Means for Solving the Problems]
The present invention will be described with reference to FIG. 1 corresponding to the embodiment. This spindle device (1) supports a main shaft (4) with a tool (11) attached to the tip by a hydrostatic magnetic compound bearing (6-9) in which a hydrostatic gas bearing and a magnetic bearing are combined. The bearings for supporting the main shaft (4) include axial type non-contact bearings (8, 9) facing the flange (4a) provided in the middle in the front-rear direction of the main shaft (4), and the main shaft ( 4) is provided with a spindle positioning mechanism (75) for moving the spindle housing (5) installed in the axial direction of the main shaft (4), and the spindle housing (5) is attached to the spindle positioning mechanism (75) at the front end. In the spindle device
Temperature measurement means (76) for measuring the temperature of the front portion of the spindle housing (5) with respect to the flange (4a), and temperature measurement support for obtaining a predetermined output from the temperature measurement value of the temperature measurement means (76). An output means (77) and a temperature correction means (83) are provided.
The predetermined output of the temperature measurement corresponding output means (77) is:
The following (1) to (2) :
(1). The output of the temperature measuring means (76) (ie the temperature measurement value ), and
(2) . A converted value obtained by converting the temperature measurement value of the temperature measuring means (76) into the axial position of the spindle tip or the axial position of the tool (11) attached to the spindle tip by a predetermined thermal displacement calculation ,
At least one of them.
The converted value may be any handleable value as position data, the actual value and in proportion to the location data, be a value that indicates the amount of displacement from the reference position have good.
The temperature correction means (83) is means for controlling the spindle positioning mechanism (75) according to the temperature measurement value or the converted value output from the temperature measurement corresponding output means (77).
According to this configuration, even if the temperature of the spindle device (1) rises due to heat generation due to loss (windage loss) or the like of the static pressure gas bearing, the temperature measurement value output from the temperature measurement corresponding output means (77) by the displacement computed converted value of the axial position, it is possible to correct the feeding amount, Ru can machine the workpiece with high precision.
Further, since the spindle positioning mechanism (75) is provided in this way and the temperature of the spindle is controlled by temperature correction using the measured temperature value or its converted value, the workpiece can be machined with high accuracy.
[0006]
In the present invention, a low thermal expansion material may be used for the main shaft (4).
The axial position of the tip of the spindle (4) or the member (11) such as a tool attached to the tip of the spindle is related to both the thermal expansion of the housing (5) and the thermal expansion of the spindle (4). ) Is difficult to measure temperature because it rotates at high speed. For this reason, a low thermal expansion material is used for the main shaft (4), and the thermal displacement correction of the main shaft tip position, etc. is performed by measuring the temperature of the housing (5), thereby making it possible to easily and accurately correct the thermal displacement, thereby achieving high-precision machining Is possible.
[0007]
In the present invention, external output means (78) for outputting the predetermined output of the temperature measurement corresponding output means (77) to the outside of the spindle device (1) may be provided. Thus, by providing the external output means (78), the numerical control device (14) of the machining apparatus (13) equipped with the spindle device (1) and other information processing means use the output to determine the spindle position. It is possible to easily perform thermal displacement correction and control when temperature is abnormal.
[0008]
In the present invention, the external output means (78) may be one that transmits to the outside of the spindle device (1) via a communication line (87).
By enabling transmission via the communication line (87) in this way, the thermal displacement status of the spindle device (1) is monitored by the remote information processing means, and appropriate commands are given or statistical processing is performed. Can be applied.
[0009]
In the present invention, the temperature measurement corresponding output means (77) may output a digital signal. By outputting as a digital signal in this way, handling of the output becomes easy.
[0010]
In the present invention, there may be provided a writing means (80) for inputting the output of the temperature measurement value or the converted value of the temperature measurement corresponding output means (77) to the storage means (79) and storing it.
By providing the writing means (80) and the storage means (79) in this way, the progress of changes in the temperature measurement value and the converted value can be examined later.
[0011]
When the writing means (80) and the storage means (79) are provided as described above, a reading means (81) for outputting stored data from the storage means (79) in accordance with an external command may be provided.
As described above, the storage data can be output by an external command, so that the storage data (79) can be easily handled.
[0012]
In this invention, a cooling means (71) for cooling the housing (5) in which the main shaft (4) is installed is provided, and in response to the output of the temperature measurement corresponding output means (77), the cooling means (71) A cooling control means (82) for controlling the cooling operation may be provided.
Thus, by appropriately controlling the cooling means (71) with the output corresponding to the temperature measurement result, appropriate cooling of the housing (5) can be easily performed.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to FIGS. The spindle device 1 is mainly composed of a spindle device body 2 and a spindle controller 3. The spindle device main body 2 supports the spindle 4 by a plurality of radial hydrostatic magnetic compound bearings 6 and 7 and axial hydrostatic magnetic compound bearings 8 and 9 installed in a housing 5, and a spindle drive source 10. It is provided. Each of the hydrostatic magnetic compound bearings 6 to 9 is a combination of a hydrostatic gas bearing and a magnetic bearing, and is controlled by the spindle controller 3. The main shaft 4 has a chuck 12 that holds the tool 11 at the tip. The spindle device 1 has a cooling means 71, and the cooling means 71 circulates a cooling medium path 72 such as a water jacket provided in the housing 5 and a cooling medium such as cooling water through the cooling medium path 72. And a cooling unit 73. The spindle device 1 is provided in a processing device 13 such as a high-speed cutting device or a grinding device, and a processing device machine part 13 a of the processing device 13 is controlled by a numerical control device 14. The housing 5 of the spindle device 1 is fixed to the housing installation base 74 and is advanced and retracted in the spindle axis direction by the spindle positioning mechanism 75 together with the housing installation base 74. The housing installation base 74 is installed on a base (not shown) through a guide so as to freely advance and retract. The spindle positioning mechanism 75 includes a servo motor and a ball screw mechanism.
[0015]
In the spindle device 1 of this embodiment, in the spindle device having such a basic configuration, the housing 5 is provided with the temperature measuring means 76, and the spindle controller 3 is provided with the temperature measurement corresponding output means 77, the external output means 78, the storage means 79, Writing means 80 and reading means 81 are provided, and the numerical control device 14 is further provided with cooling control means 82, temperature correction means 83, forced stop means 88, and alarm means 89. The main shaft 4 is made of a low thermal expansion material such as a low thermal expansion soft magnetic material such as an invar material.
[0016]
The spindle device main body 2 will be described with reference to FIGS. The spindle device 1 is a built-in motor type spindle device of the processing device 13, and the spindle drive source 10 is installed in a housing 5 in which the bearings 6 to 9 are installed. The spindle drive source 10 composed of this motor includes a rotor 21 provided integrally with the main shaft 4 and a stator 22 installed on the housing 5. The housing 5 is formed in a substantially cylindrical shape. The spindle drive source 10 may not be a built-in type, but may be provided outside the housing 5 to transmit rotation to the main shaft 4 via a transmission mechanism.
In this example, the bearings 6 to 9 and the spindle drive source 10 are arranged such that the front part (tool side part) and the rear part of the main shaft 4 are supported by radial hydrostatic magnetic composite bearings 6 and 7, and the middle part is axial. It is configured such that a spindle drive source 10 is arranged at the rear end, supported by static hydrostatic magnetic composite bearings 8 and 9. Instead of the above arrangement, even if the intermediate spindle drive source 10 of the two radial bearings 6,7 and placed not good. Further, the axial bearings 8 and 9 may be non-contact bearings, and a single magnetic bearing or a static pressure gas bearing may be used instead of the static pressure magnetic composite bearing.
[0017]
Each of the radial type hydrostatic magnetic composite bearings 6 and 7 has the same configuration. FIG. 3 shows a cross section of one of the bearings 6 and FIG. 4 shows an enlarged vertical cross section. The hydrostatic magnetic composite bearings 6 and 7 are obtained by combining hydrostatic gas bearings 6A and 7A and magnetic bearings 6B and 7B, respectively. The term “composite” as used in this specification means that both static pressure and magnetic bearings are combined so that a common part is generated. For example, a common part (radial bearing) is formed on a static pressure gas bearing surface and a magnetic bearing surface. Then, the axial overlapping portion) may be generated, or at least a part of components may be shared by both types of bearings.
[0018]
In this embodiment, as shown in FIG. 4, by providing the diaphragm 23a of the static pressure gas bearings 6A and 7A on the core 23 of the electromagnet of the magnetic bearings 6B and 7B, the bearing components can be shared and the bearing surface A part is overlapped in the axial direction. The core 23 is opposed to a pair of main core portions 23a, 23a separated in the axial direction, a connecting core portion 23b connecting the main core portions 23a, 23a, and spindle ends of both the main core portions 23a, 23a. A longitudinal section is formed in a C shape by the extending portions 23c, 23c. The inner diameter side surfaces of the main core portion 23a and the extending portion 23c are cylindrical surfaces that form a predetermined magnetic gap with the main shaft 4. The magnetic bearings 6 </ b> B and 7 </ b> B are obtained by winding a coil 25 around the connecting core portion 23 b of the core 23. The coil 25 is embedded in a nonmagnetic material 26 such as a resin material.
[0019]
The static pressure gas bearings 6A and 7A are formed on the inner surface of the core 23 and the nonmagnetic body 26 to form a bearing gap d between the main shaft 4 and the main cores of the core 23. The diaphragm 24a is provided in the portions 23a and 23a and opens to the hydrostatic bearing surfaces 6Aa and 7Aa. The restrictor 24a is provided at the tip of the air supply hole 24 opened on the outer diameter side surface of each main core portion 23a.
As shown in the stepped cross section in FIG. 3, the cores 23 are arranged at a plurality of circumferential locations around the main shaft 4 (four locations in the example in the figure) and are fixed to the housing 5. A gap between adjacent cores 23 in the circumferential direction is filled with a nonmagnetic material 27 such as a resin material. The nonmagnetic material 27 may be integrated with the nonmagnetic material 26 (FIG. 4) around the coil 25.
[0020]
The magnetic bearings 6 </ b> B and 7 </ b> B have displacement detection means 28 that detects the displacement of the magnetic gap between the main shaft 4 and the core 23. The displacement detection means 28 may directly detect the amount of displacement, but in this example, by detecting the static pressure of the hydrostatic bearing gap d, the detected pressure value is converted into the amount of displacement. Thus, the displacement of the magnetic gap is detected. Specifically, the displacement detection means 28 includes a pressure detection air passage 28a having a tip opened in the hydrostatic bearing gap d and a sensor 28b communicating with the air passage 28a. The sensor 28b is disposed at a position away from the core 23 in the axial direction as shown in FIG. The air passage 28a is formed of a fine hole or a pipe, and the hydrostatic bearing gap d is opened at a portion of the nonmagnetic material 26 between the extending portions 23c and 23c of the core 23. FIG. 2 shows the opening positions of the throttle 24a and the air passage 28a shifted in the circumferential direction in order to make the drawing easy to see, but in actuality, they are the same in the circumferential direction.
[0021]
FIG. 5 is an enlarged view of the axial type hydrostatic magnetic composite bearings 8 and 9. The pair of bearings 8 and 9 are installed in the housing 5 so as to face both surfaces of the flange portion 4 a provided on the main shaft 4, and constitute one double-sided axial type hydrostatic magnetic bearing 30. To do. The hydrostatic magnetic composite bearings 8 and 9 on both sides have the same configuration. These hydrostatic magnetic composite bearings 8 and 9 are obtained by combining hydrostatic gas bearings 8A and 9A and magnetic bearings 8B and 9B, respectively.
In this embodiment, by providing the diaphragm 33a of the static pressure gas bearings 8A and 9A on the core 33 of the electromagnet of the magnetic bearings 8B and 9B, the bearing components are shared and a part of the bearing surface overlaps in the axial direction. It is like that. The core 33 is formed in a C-shaped longitudinal section so that an opening 33d is formed on the surface facing the spindle flange 4a, and a coil 35 is accommodated therein. The opening 33d is filled with a nonmagnetic material. In the illustrated example, the core 33 has an assembly configuration of an inner peripheral core portion 33a and an outer peripheral core portion 33b having an L-shaped cross section, but may be a single piece. A spacer 29 is adjacent to the core 33 in the axial direction.
[0022]
The axial type static pressure gas bearings 8A and 9A are provided on the core 33 and static pressure bearing surfaces 8Aa and 9Aa which are formed on the side surface of the core 33 and form a bearing gap d2 with the spindle flange 4a. The diaphragm 34a is open to the pressure bearing surfaces 8Aa and 9Aa. The restrictor 34 a is provided at the tip of the air supply hole 34 that opens to the outer diameter side surface of the core 33.
[0023]
The axial type magnetic bearings 8B and 9B have a displacement detecting means 38 for detecting the displacement of the magnetic gap between the spindle flange 4a and the core 33. This displacement detection means 38 may also directly detect the amount of displacement, but in this example, by detecting the static pressure in the hydrostatic bearing gap d2, the detected pressure value is converted into the amount of displacement. Thus, the displacement of the magnetic gap is detected. Specifically, the displacement detection means 38 includes a pressure detection air passage 38a having a tip opened in the hydrostatic bearing gap d2, and a sensor 38b (FIG. 2) communicating with the air passage 38a.
[0024]
In the static pressure gas bearings 6A to 9A in the static pressure magnetic composite bearings 6 to 9, the compressed air or other compressed gas is supplied to the supply holes 24 and 34 from the supply inlet 40a of the supply hole 40 provided in the housing 5. Is supplied.
[0025]
The control system will be described. In FIG. 1, the spindle controller 3 has a basic function of giving an excitation current to the magnetic bearings 6 </ b> B to 9 </ b> B of the hydrostatic magnetic composite bearings 6 to 9 according to the detection values of the displacement detection means 28 and 38.
The temperature measuring means 76 provided in the spindle housing 5 detects the housing temperature on the tip side of the flange 4a of the main shaft 4, and a temperature sensitive element such as a platinum resistance element or a thermocouple is used. The temperature measuring unit 76 may use a measured value of the resistance of the electromagnet coil 25 (FIG. 4) of the magnetic bearing 6.
[0026]
In this example, the temperature measurement corresponding output unit 77 includes a comparison unit 84 and a digital conversion unit 85. The comparison unit 84 compares the temperature measurement value output from the temperature measurement unit 76 with a set value serving as a threshold value, and outputs an abnormal signal when the set value is exceeded. A comparator is used. The comparing means 84 may correspond to a plurality of set values and output a plurality of stages of abnormal signals. The digital conversion means 85 is a means for converting the output of the analog signal of the temperature measurement means 76 into a digital value. When the output of the comparison means 84 is a simple binary signal, the output of the comparison means 84 is indicated by a plurality of digits. It also serves as a means for converting to a digital value. The temperature measurement corresponding output unit 77 outputs the temperature measurement value output from the digital conversion unit 85 or an abnormal signal based on the digital value. The abnormal signal of the comparison means 84 may be used as the output of the temperature measurement corresponding output means 77 as it is.
[0027]
The writing unit 80 is a unit that causes the storage unit 79 to store a digital temperature measurement value and an abnormality signal that are output from the temperature measurement corresponding output unit 77. The storage means 79 is capable of accumulating and storing these temperature measurement values and abnormal signals output one after another. The storage means 70 is composed of a magnetic disk device, other large-capacity storage devices, etc. in addition to memory elements.
[0028]
The external output means 78 is a means for outputting each output of the temperature measurement corresponding output means 77 to the outside of the spindle controller 3 and may be an interface consisting of a simple output port. The reading means 81 is provided. The communication function unit 86 is means for communicating with a remote place via a communication line 87 such as a telephone line network or a data communication line network. The reading unit 81 is a unit that outputs stored data from the storage unit 79 in response to a command from the outside of the spindle controller 3, and measures the temperature during any spindle operation stored in the storage unit 81 in response to the external command. Values and error signals can be output.
[0029]
The numerical control device 14 is means for controlling the machining device machine unit 13 in accordance with the machining program, and has a numerical control function unit that mainly controls the axis feed function and a programmable controller function unit that mainly performs sequence control. Yes. The programmable controller function section is provided with temperature correction means 83, cooling control means 82, forced stop means 88, and alarm means 89. The temperature correction means 83 may be provided in the numerical control function unit.
The forcible stop means 88 is means for forcibly stopping the processing apparatus 13 in response to an abnormal signal output from the temperature measurement corresponding output means 77 via the external output means 78. The alarm means 89 is a means for generating an alarm in response to an abnormal signal output from the temperature measurement corresponding output means 77 via the external output means 78. As an alarm, an alarm sound is generated, an alarm lamp is lit, and a display is displayed. Displays alarms on the device screen.
[0030]
The cooling control means 82 is means for controlling the cooling means 71 in response to an abnormal signal output from the temperature measurement corresponding output means 77 via the external output means 78. For example, the cooling control means 73 instructs the cooling unit 73 to increase the cooling intensity. give.
[0031]
The temperature correction unit 83 is a unit that controls the spindle positioning mechanism 75 in accordance with the temperature measurement value output from the temperature measurement corresponding output unit 77 via the external output unit 78. That is, the movement amount of the spindle positioning mechanism 75 is basically controlled according to the command value of the machining program, but the temperature correction means 83 uses this feed amount according to the temperature measurement value according to a predetermined temperature correction arithmetic expression. change.
In this temperature correction calculation, for example, a calculation is performed in which a change amount associated with a temperature change in the dimension (C dimension) from the spindle device mounting position P to the tool tip is added as a correction value of the spindle feed amount. The C dimension indicating the axial position of the tool tip is the dimension (A dimension) of the main shaft 4 from the tip of the tool 11 to the spindle flange 4a and the dimension of the housing 5 from the spindle device mounting position P to the spindle flange 4a ( B dimension). Accordingly, the C-dimensional thermal expansion amount is calculated from the difference between the B-dimensional housing thermal expansion amount and the A-dimensional spindle thermal expansion amount. Since the housing 5 and the main shaft 4 are not in contact with each other, there is a difference in temperature and temperature change. Therefore, the temperature measuring means 76 of the housing 5 cannot measure the temperature of the main shaft 4. Therefore, the thermal expansion amount of the main shaft 4 may be calculated at a temperature estimated from the temperature detected by the temperature measuring means 76, or the spindle thermal expansion amount may be ignored. For this reason, when a low thermal expansion material is used for the main shaft 4, the error of thermal expansion correction can be small.
[0032]
FIG. 6 shows another embodiment of the present invention. In this embodiment, the temperature measurement corresponding output unit 77A includes a conversion unit 90 and a comparison unit 84A in the subsequent stage. Further, the temperature measurement corresponding output means 77A has a digital conversion means 85A in the input section, and a signal obtained by converting the temperature measurement value into a digital value is input to the conversion means 90. The conversion means 90 converts the temperature measurement value of the temperature measurement means 76 into the axial position of the tip end of the spindle 4 or the axial position (C dimension) of the tip of the tool 11 which is a member attached to the tip of the spindle by a predetermined thermal displacement calculation. Convert to. The comparing means 84A compares the converted value output from the converting means 90 with a set value, and outputs an abnormal signal when the converted value exceeds the set value. The temperature measurement corresponding output unit 77A outputs the temperature measurement value output of the digital conversion unit 85A, the output of the conversion unit 90, and the abnormality signal of the comparison unit 84A.
The external output means 78 outputs the above outputs of the temperature measurement corresponding output means 77A to the outside of the spindle controller 3. Further, the writing unit 80 causes the storage unit 79 to store the above outputs of the temperature measurement corresponding output unit 77A.
The temperature correction unit 83 </ b> A performs a temperature correction calculation using the converted value output from the conversion unit 90.
[0033]
Other configurations and functions in this embodiment are the same as those in the embodiment of FIG. In this embodiment, instead of comparing the converted values, the comparison means 84A may compare the temperature measurement value of the temperature measurement means 76 with the set value and output an abnormal signal as in the embodiment of FIG. Alternatively, the temperature measurement value obtained by the digital value converted by the digital conversion means 85A of the temperature measurement means 76 may be compared with a set value to output an abnormal signal.
For example, the abnormality signal is generated by comparing the temperature measurement value (or its digital conversion value) of the temperature measurement means 76 with the comparison means 84A, and the converted value output of the conversion means 90 is output to the temperature correction calculation by the temperature correction means 83A. Use.
[0034]
According to the spindle device 1 of the embodiment of FIGS. 1 and 6, even if the temperature of the spindle device 1 changes, the spindle positioning amount can be corrected for temperature, and the workpiece can be processed with high accuracy. Further, when the spindle device is abnormal due to an excessive rise in the housing temperature, a signal can be output to the outside to stop the spindle device 1 or issue an alarm.
[0035]
Although each said embodiment demonstrated the case where the spindle apparatus 1 has the static pressure magnetic compound bearings 6-9, it can be applied also to the spindle apparatus which supports the main axis | shaft 4 only with a static pressure gas bearing. For example, in each of the above embodiments, only the static pressure gas bearings 6A to 9A may be provided as shown in FIG. 8 instead of the static pressure magnetic composite bearings 6 to 9.
[0036]
Next, the communication system will be described. FIG. 7 shows a development example of the communication system of the spindle device 1 of FIG. 1 or FIG. 6 and the machining device 13 equipped with the spindle device 1. A plurality of other processing devices 102 are installed in the office 101 where the processing device 13 is installed, and these processing devices 13 and 102 are each independently or a plurality of information processing means 103 and 104 are shared. It is connected. These information processing means 103 and 104 constitute a local area network 119 together with network components such as the web server 110, the fiber wall 111, and the router 112. This local area network 119 is connected via a communication line 116 to a remote information processing means 121 installed in a local area network of another office 113, 114 via the Internet 120 via a communication line 87. Yes.
The processing device 13 is basically configured such that the numerical control device 14 is connected to the information processing means 103 and connected to a communication line in the local area network 119 via the information processing means 103. In combination with this, or separately from this, the communication means provided in the numerical controller 14 or directly from the communication function part 86 (FIGS. 1 and 6) of the external output means 78 provided in the spindle controller 3. A communication system connected to a communication line in the local area network 119 may be provided.
[0037]
【The invention's effect】
In the spindle device of the present invention, a spindle having a tool attached to the tip is supported by a hydrostatic magnetic compound bearing in which a hydrostatic gas bearing and a magnetic bearing are combined, and the spindle is supported by a front and rear of the spindle as a bearing for supporting the spindle. A spindle positioning mechanism for moving the spindle housing on which the spindle is installed in the axial direction of the spindle, including an axial-type non-contact bearing facing a flange provided in the middle of the direction, the spindle housing at the front end In the spindle apparatus attached to the spindle positioning mechanism, temperature measuring means for measuring the temperature of the front portion of the spindle housing from the flange portion, and temperature measurement corresponding output for obtaining a predetermined output from the temperature measurement value of the temperature measuring means And the predetermined output is the following (1) to (2) , that is, (1) . The output of the temperature measuring means, and (2) . The temperature measurement value includes at least one of a temperature measurement value of the temperature measuring means converted into an axial position of a spindle tip or an axial position of a tool attached to the spindle tip by a predetermined thermal displacement calculation, and the temperature measurement Since the temperature correction means for controlling the spindle positioning mechanism according to the temperature measurement value output from the corresponding output means or the converted value is provided , the workpiece can be processed with high accuracy even if the temperature of the housing or the like changes. can Ru.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a conceptual configuration of a spindle device according to an embodiment of the present invention.
FIG. 2 is a longitudinal sectional side view of the spindle device main body.
FIG. 3 is a cross-sectional front view of the spindle apparatus main body.
FIG. 4 is an enlarged sectional view of a radial type hydrostatic magnetic composite bearing.
FIG. 5 is an enlarged cross-sectional view of an axial type hydrostatic magnetic composite bearing.
FIG. 6 is a block diagram showing a conceptual configuration of a spindle device according to another embodiment of the present invention.
FIG. 7 is an explanatory diagram of a conceptual configuration of a communication system connected to the spindle device of the present invention.
FIG. 8 is a sectional view of a spindle device body of a spindle device according to still another embodiment of the present invention.
FIG. 9 is a cross-sectional view of a conventional spindle device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Spindle apparatus 75 ... Spindle positioning mechanism 2 ... Spindle apparatus main body 76 ... Temperature measurement means 3 ... Spindle controller 77, 77A ... Temperature measurement corresponding | compatible output means 4 ... Main axis | shaft 78 ... External output means 5 ... Housing 79 ... Memory | storage means 6-9 ... Static pressure magnetic compound bearing 80 ... Writing means 6A to 9A ... Static pressure gas bearing 81 ... Reading means 6B to 9B ... Magnetic bearing 82 ... Cooling control means 10 ... Spindle drive source 83, 83A ... Temperature correction means 13 ... Processing device 84 84A ... Comparison means 14 ... Numerical control device 85,85A ... Digital conversion means 71 ... Cooling means 87 ... Communication line 74 ... Spindle device installation table 90 ... Conversion means

Claims (8)

The main shaft the tool is attached to the distal end, the externally pressurized gas bearing and a magnetic bearing is supported by a combined externally pressurized gas and magnetic bearing assembly which is complexed, as a bearing for supporting the main shaft, is provided in the longitudinal direction of the intermediate of the main shaft A spindle positioning mechanism that includes an axial non-contact bearing facing the flange and moves the spindle housing on which the spindle is installed in the axial direction of the spindle, and the spindle housing is attached to the spindle positioning mechanism at the front end In the spindle device
A temperature measuring means for measuring the temperature of the portion of the spindle housing in front of the flange portion and a temperature measurement corresponding output means for obtaining a predetermined output from the temperature measurement value of the temperature measuring means are provided, and the predetermined output is:
The following (1) to (2) :
(1 ). Output of the temperature measuring means, and
(2) . A converted value obtained by converting the temperature measurement value of the temperature measurement means into an axial position of the spindle tip or a tool attached to the spindle tip by a predetermined thermal displacement calculation,
Including at least one of
A spindle apparatus comprising temperature correction means for controlling the spindle positioning mechanism in accordance with a temperature measurement value output from the temperature measurement corresponding output means or the converted value .   The spindle device according to claim 1, wherein a low thermal expansion material is used for the main shaft.   3. A spindle apparatus according to claim 1, further comprising an external output means for outputting the predetermined output of the temperature measurement corresponding output means to the outside of the spindle apparatus. The spindle device according to claim 1,
A spindle apparatus provided with external output means for transmitting the predetermined output of the temperature measurement corresponding output means to the outside of the spindle apparatus via a communication line.   5. The spindle apparatus according to claim 4, wherein the temperature measurement corresponding output means outputs a digital signal.   6. The spindle device according to claim 1, further comprising a writing unit configured to input an output of the temperature measurement value or the converted value of the temperature measurement corresponding output unit into a storage unit to store the output.   7. The spindle apparatus according to claim 6, further comprising a reading unit that outputs stored data from the storage unit in response to an external command.   8. The cooling device according to claim 1, further comprising cooling means for cooling the housing on which the spindle is installed, and cooling control means for controlling the cooling operation of the cooling means in response to the output of the temperature measurement corresponding output means. The spindle device according to any one of the above.

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