JPH069357U - Air bearing motor - Google Patents

Abstract

(57) [Summary] [Structure] In an air bearing motor, instead of the motor shaft of the conventional motor unit and the rotor shaft that is integrally connected in series to the motor shaft, the motor unit such as the core, coil, and magnet is installed in the rotor shaft. An air bearing motor characterized by being installed side by side. [Effect] Since the motor part in which the motor shafts are installed side by side is built in the rotor shaft, the overall length corresponding to the motor part is shortened. Moreover, one color is sufficient for the motor cover and two collars, which were conventionally required by connecting in series, and the number of parts has been reduced. Furthermore, the greatest advantage of the present invention is that the entire gas flow path is shortened for structural simplification, and that a cylindrical coil is arranged in the cavity inside the rotor shaft, so both sides of the coil are also cooled. The efficiency of being able to do it can be demonstrated.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an air bearing motor, and more particularly to an air bearing motor having a compact and simplified structure for a rotor shaft.

[0002]

[Prior art]

 Conventionally, an air bearing motor is known, and usually has a structure in which the motor shaft of the motor is arranged in series with the rotor shaft in the air bearing portion. For this reason, the structure becomes large horizontally protruding, and for this reason, the gas originally supplied to the air bearing part is complicatedly branched and supplied to not only the rotor shaft part but also the motor part. The bearing function of the rotor shaft, the bearing function of the material of the motor drive part, and the cooling function were performed separately in the horizontally long layout. This not only complicates the gas supply circuit, but also requires a separate mechanical member for mounting the motor section. An example of such a conventionally known air bearing motor is shown in FIG. 4 attached hereto. As is clear from this example, in the conventional product, the motor shaft of the motor unit is connected in series adjacent to the air bearing unit. Not only to float the rotor shaft and the motor part but also to cool them respectively, a complicated and long gas flow path and the above mechanical member for fixing the motor part, such as the motor cover 9 and the collar. A10, color B11, etc. were required. For this reason, the entire length of the motor shaft and rotor shaft is increased, and it is necessary to consider the occupied area and other factors at the installation site as well, which has caused various complicated restrictions in handling.

[0003]

[Problems to be solved by the device]

 The present invention was made by paying attention to the above-mentioned conventional problems, and a motor unit was incorporated inside the rotor shaft of the air bearing unit, and the air passage was improved to reduce the size of the entire structure. Efficient air bearing by arranging an efficient air passage between the air bearing part and the motor part and using the air flow path supplied to the air bearing part also as the cooling air flow path for the rotating member of the motor part The purpose is to provide a motor.

[0004]

[Means for Solving the Problems]

 The air bearing motor according to the present invention has a core, a coil, a magnet, and other electric members required for motor rotation built-in inside the rotor shaft of the air bearing to reduce the overall length and a circuit of gas supplied to the air bearing portion. Are integrated to efficiently cool the electric member.

[0005]

[Action]

 Since the air bearing motor in this invention has the motor part installed side by side in the air bearing part, the entire structure can be made smaller than the conventional one, which is arranged in series. The gas flow path used for cooling the motor part can be shortened in a circuit by branching from the gas flow path supplied to the motor part, and it can be efficiently used. Also, the mechanical parts for attaching the motor part to the air bearing part can be omitted.

[0006]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings.

The air bearing motor of the present invention is roughly classified into an inner type and an outer type according to the magnet position of the motor when the motor is housed in the air bearing.

FIG. 4 is an upper half cross-sectional explanatory view showing a conventional typical air bearing motor, which is to be lifted up for comparison. This conventional air bearing motor has a motor part adjacent to the conventional air bearing part, and the rotor shaft of the air bearing part and the motor shaft integrally connected to the rotor shaft are arranged in series in the axial direction. Therefore, the whole structure becomes long. In addition, a mechanical support member such as a collar is required to attach this motor to the air bearing part, and in addition to the air bearing function that originally functions to supply to the air bearing part and the motor part, it also cools the drive member of the motor part. Function is maintained by the relatively long gas flow path. In FIG. 4, 1 is a rotor shaft, 2 is a screw for attaching the main body cover 16 for providing the air pressure chamber 13 in the main body of the motor, and 3 is a gas for letting gas flow at a uniform pressure by the plurality of nozzles 12. Is an air ring, 4 is an air tube for supplying air, 5 is an air joint for connecting the air tube 4, 6 is a magnet of the motor portion, and 7 is a core 17 for rotating the magnet. The reference numeral 8 is a coil wound around the motor, and 8 is a Hall IC, which detects the rotation of the sensor magnet 14 attached to the motor shaft integral with the rotor shaft 1 in the motor section and outputs the signal (for example, It is transmitted to the base of the transistor) and is attached to the substrate 21. Further, 9 is a motor cover, 10 and 11 are a collar A and a collar B which hold a magnet by a nut 18, and 19 is a pin for inserting a plug 20 connected from a power source. Reference numeral 15 is a lead wire for connecting the power source, the Hall IC, and the coil motor unit and circuit unit.

Next, the operation of the air bearing motor having the above structure will be described. First, the air from the air tube is pressure-equalized by the air pressure chamber 13 and discharged from the nozzle 12 to the periphery of the air bearing 1, and then a part of the air is discharged from the left to the outside. And then discharged to the outside from above.

In this way, the current supplied from the power supply to the two-phase motor, for example, flows from the pin 19 to the coil 7 to excite the current to rotate the magnet 6 and start the rotation of the motor shaft and the rotor shaft. By this rotation, the signal from the sensor magnet 14 attached to the motor shaft is detected by the Hall IC 8 which is attached to the motor shaft by shifting 90 ° to the motor shaft, and the signal is transmitted to the transistor, and the signal from the transistor is further transmitted. By detecting with the Hall IC on the other side, electromagnetic waves are alternately supplied to the two-phase coils to rotate the motor shaft to which the magnet is attached and the shaft rotor 1 integrated with the motor shaft.

1 and FIG. 2, which is an XX cross section of FIG. 1, show an inner type air bearing motor as one embodiment of the present invention, and the reference numerals in the drawings are the same as those in FIG. In this mode, since the magnet 6 is located inside the coil 7, that is, on the motor shaft, it is an inner type. 3 shows an outer type air bearing motor as another embodiment of the present invention, and the reference numerals in the drawing are the same as those in FIGS. In this mode, since the magnet 6 is located outside the coil 7 with respect to the motor shaft, that is, on the inner wall of the rotor shaft 1, it is an outer type. In FIGS. 1 and 3, the coil 7 has one end inserted in the hollow portion 24 in a cylindrical groove of the motor body 25. The inner type shown in FIG. 1 has a magnet 6 fixed to the inside of the rotor shaft 1 inside the cylinder of the coil, and the outer type shown in FIG. 3 has a cylindrical coil 7 fixed to the outside of the rotor shaft 1. In this case, the Hall IC 8 is arranged at a required position inside the coil, shifted by 90 °, and the sensor magnet is installed inside the rotor shaft so as to face the Hall IC.

In FIGS. 1 and 3, pressurized air sent from an appropriate compressor (not shown) is guided to an air joint 5 of an air bearing motor by an air tube 4. A gas flow, which is air, is temporarily stored in the air pressure chamber 13 from the air joint 5, adjusted by a valve or the like, and then sent from the nozzle 12 of the air cylinder 3 to the slit between the outer diameter of the roll shaft 1 and the inner diameter of the air ring 3. And is discharged to one of the passage outlets A. Further, the gas flow passes through the inner diameter of the rotor shaft 1, the slit between the coil 7 and the magnet 6 and flows to the other passage outlet B. When the pressurized gas flows through these slits and the introduced gas pressure and the discharged gas pressure are balanced, the rotor shaft 1 is brought into non-contact with other members due to the pressurized gas, and the air bearing, that is, the air bearing against the load. It exerts the function of a bearing.

On the other hand, apart from the air bearing member, the magnetic motor circuit is formed by a conventional means. For example, in the inner type air bearing motor shown in FIG. 1, the above-mentioned magnetic circuit is provided between the coil member provided in the inner diameter of the rotor shaft 1, that is, the coil 7, the coil holder 9 and the magnet 6. Further, of the two phases of the Hall IC and the coil 7, the coil A phase is synchronized, and another Hall IC and the coil B phase are synchronized so that the phase difference at that time is 90 °. Further, the N pole and the S pole of the magnet 6 are detected and the transistors of the external drive circuit are switched to energize the respective coils A phase and B phase to generate a coil magnetic field. As a general rule, the magnet mounted coaxially with the rotor shaft 1 serves as an inlet / outlet shaft to rotate the rotor shaft, which is already known. In the case of the outer type air bearing motor shown in Fig. 3, the motor is rotated by a similar magnetic circuit only by arranging the magnet and coil in the opposite positions to the former.

[0014]

[Effect of device]

 As described above, according to the present invention, the electric member necessary for rotation is installed side by side inside the rotor shaft of the air bearing as a motor part, so that the motor is connected to the air bearing part in series like the conventional similar motor. The entire length can be shortened in the axial direction only at the portion corresponding to the motor section, without having to install it in the. Therefore, it is possible to omit the members such as the motor cover, the collar A, and the collar B, which are necessary to install the motor section, and it is possible to reduce the cost. Moreover, the greatest advantage of the present invention is that the entire gas flow path can be shortened, and the complexity of the branching of the flow path is higher than that of the same type motor in which the conventional motor part and air bearing part are separate. Can be resolved. Moreover, in the conventional product, the coil was placed on the outer wall of the motor part and both sides of the coil could not be cooled, whereas in the present invention, both the inner type and the outer type, not only the magnet but also both sides of the coil can be cooled. Since a gas flow path can be provided, the effect that the motor part can be cooled by discharging the gas from the gas passage outlet B without requiring a complicated branch from the gas flow originally necessary for the air bearing is obtained.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing the structure of an inner type air bearing motor according to the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is a longitudinal sectional view showing the structure of an outer type air bearing motor according to the present invention.

FIG. 4 is an explanatory longitudinal sectional view showing the structure of a conventional air bearing motor.

[Explanation of symbols]

 1 Rotor shaft 3 Air ring 6 Magnet 7 Coil 9 Coil holder 10, 11, 23 Color A, B Gas (air) flow

Claims (1)

[Scope of utility model registration request] 1. An air bearing motor composed of an air bearing portion and a motor portion, wherein electric motor members such as a core, a coil, and a magnet as a motor portion are built side by side inside the rotor shaft of the air bearing. Air bearing motor to do.