JP2007276022A - Rotary shaft support device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means, accurately detecting the temperature of a rolling bearing of a rotary shaft support device and also restraining loss torque of a rotary shaft in detecting the rotating speed. <P>SOLUTION: The rotary shaft support device 1 includes: a housing 7 to which an outer ring 2a of an angular ball bearing 2 is fixed; a screw shaft 5 fitted to an inner ring 2b; and a seal 22 for sealing the angular ball bearing 2, wherein the screw shaft 5 is provided with a rotation detecting plate 18 disposed outside the seal 22, and the housing 7 is provided with: a temperature sensor 28 for detecting the temperature of the angular ball bearing 2; and a rotation sensor 25 for detecting the rotating speed of the screw shaft 5 by the rotation detecting plate 18. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a rotary shaft support device that rotatably supports a rotary shaft such as a drive shaft and a driven shaft provided in a mechanical device and a screw shaft of a ball screw device.

When the rotation support device is used in a drive device or a test device, in order to maintain an appropriate operation state, the rotation support device detects the temperature of the rolling bearing for grasping the maintenance time and the rotation for managing the rotation state. There is a need to detect the rotational speed of the shaft.
For this reason, the temperature of the rolling bearing is generally detected by attaching a temperature sensor to the outer surface of the housing where the rolling bearing is installed with a sticking means such as tape, and the worker periodically checks the temperature of the rolling bearing. The maintenance time is determined based on the deterioration of the lubricant.

  In addition, the rotation speed of the rotating shaft is generally detected using a rotary encoder installed in a driving device such as a servo motor that drives the rotating shaft, and the coupling that connects the rotating shaft and the driving device is loosened. If the lock nut that fixes the inner ring of the rolling bearing to the rotating shaft is loosened, the actual rotational speed of the rotating shaft cannot be detected, making it difficult to grasp the rotating state of the rotating shaft. .

In order to detect the actual rotational speed of this rotating shaft, the conventional rotating shaft support device is equipped with a rotation detector that is magnetized in multiple poles on the inner ring inside the sealing seal of the rolling bearing, or a gear, a holed plate, etc. A rotation detection plate equipped with a ferromagnetic rotation detection unit is attached, and the number of rotations of the rotary shaft is detected from the outside of the hermetic seal by a hall sensor or a rotation sensor equipped with an operating magnet, and the sensor signal is transmitted via a signal line. (For example, refer to Patent Document 1).
JP-A-10-160744 (mainly, page 3, paragraphs 0011-0012, FIG. 1)

  However, in the technique of the conventional patent document 1 described above, a rotation detection plate is attached to the inner ring inside the sealing seal of the rolling bearing, and the rotation number of the rotating shaft is detected by a rotation sensor provided outside the sealing seal. Therefore, in a rotary shaft support device having a rolling bearing lubricated by a semi-solid lubricant such as grease, the rotational energy is detected when the rotation detection plate or its rotation detection unit agitates the semi-solid lubricant. And the loss torque of the rotating shaft increases.

In a rotary shaft support device provided with a rolling bearing lubricated by a liquid lubricant such as lubricating oil, the rotation is performed when the liquid lubricant adhering to the rotation detection portion of the rotation detection plate is scattered radially outward. There is a problem that energy is consumed and the loss torque of the rotating shaft increases.
This is particularly noticeable in the case of a rotation detection plate having a gear type rotation detection unit.
In addition, when detecting the temperature of a rolling bearing by a general technique, since the temperature sensor is affixed to the outer surface of the housing, there is a problem that the detected temperature changes greatly due to the influence of the surrounding environment such as forced cooling. is there.

  The present invention has been made to solve the above problems, and provides a means for accurately detecting the temperature of the rolling bearing of the rotating shaft support device and suppressing the loss torque of the rotating shaft in detecting the rotational speed. The purpose is to do.

  In order to solve the above problems, the present invention includes a rolling bearing having an outer ring and an inner ring, a housing for fixing the outer ring, a rotating shaft fitted to the inner ring, and a hermetic seal for sealing the rolling bearing. In the rotation shaft support device provided, the rotation shaft is provided with a rotation detection plate on which a rotation detecting portion having irregularities is formed, the rotation detection plate is disposed outside the hermetic seal, and the rolling is mounted on the housing. A temperature sensor for detecting the temperature of the bearing and a rotation sensor for detecting the rotation speed of the rotation shaft by the rotation detection plate are attached.

  As a result, the present invention makes it possible to accurately detect the temperature in the vicinity of the outer ring of the rolling bearing by minimizing the influence of the surrounding environment on the temperature sensor, and detects an increase in the temperature of the rolling bearing due to poor lubrication or the like. As a result, the maintenance time can be accurately determined, and the loss of rotational energy associated with the rotation of the rotation detection plate can be reduced only to the wind loss, thereby reducing the loss torque in detecting the rotational speed of the rotating shaft. It is done.

  Embodiments of a rotating shaft support device according to the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view illustrating a rotary shaft support device according to a first embodiment, and FIG. 2 is a front view illustrating the rotary shaft support device according to the first embodiment.
FIG. 1 shows a cross section along the line A-O-A in FIG.
In FIG. 1, 1 is a rotating shaft support device.
Reference numeral 2 denotes an angular ball bearing as a rolling bearing. In this embodiment, the two angular ball bearings 2 are arranged in front combination and are lubricated by a lubricant such as grease.

The angular ball bearings 2 arranged in the front combination include an outer ring raceway having a substantially arc-shaped cross section formed on the inner peripheral surface of the outer ring 2a and an inner ring raceway having a substantially arc-shaped cross section formed on the outer peripheral surface of the inner ring 2b. And a plurality of balls 3 arranged so as to be rotatable at a predetermined pitch.
Reference numeral 5 denotes a screw shaft of a ball screw device serving as a rotating shaft. A spiral shaft raceway groove 5a having a substantially semicircular arc cross-sectional shape is formed on the outer peripheral surface thereof, and is coaxial with the screw shaft 5 at its end. A stepped shaft-shaped mounting portion 6 is formed on the inner peripheral surface of the inner ring 2 b of the angular ball bearing 2.

The screw shaft 5 is screwed with a nut raceway groove facing a shaft raceway groove 5a formed on the inner peripheral surface of the nut (not shown) via a steel ball, and the screw shaft 5 rotates to turn the nut into the screw shaft. 5 is moved in the axial direction.
Reference numeral 7 denotes a housing, which is formed by fastening a lid body 9 to a main body portion 8 with mounting bolts 10 shown in FIG.

  The main body 8 of the housing 7 is a cylindrical member made of a steel material such as alloy steel, and an inner ring has an outer ring fitting hole 11 fitted to the outer ring 2a of the outer ring 2a of the angular ball bearing 2. A locking portion 12 for locking one outer ring 2a is formed, and a flange portion 13 is integrally formed on the outer peripheral surface thereof, and a frame of a mechanical device (not shown) or the like by a stepped bolt hole 14 provided in the flange portion 13 It is fixed with bolts.

The lid 9 (outer ring pressing plate) of the housing 7 is a donut plate-like member made of a steel material such as alloy steel, and the other outer ring 2 a is pressed by the pressing portion 15 to fix the outer ring 2 a to the housing 7. At the same time, it has a function of applying a preload to the angular ball bearing 2 of the front combination.
Reference numeral 16 denotes an inner ring spacer, which is a cylindrical member made of a steel material such as alloy steel, and is disposed between the inner ring 2b of one angular ball bearing 2 and the shaft step portion 5b of the screw shaft 5.

Reference numeral 18 denotes a rotation detection plate, which is made of a steel material such as alloy steel, and is a disc-like member formed integrally with the outer peripheral surface of the hub portion 19 formed in the same manner as the inner ring spacer 16. Is formed with a rotation detecting portion 18a having gear-like irregularities, and is arranged adjacent to the opposite side of the inner ring spacer 16 of the inner ring 2b of the other angular ball bearing 2.
Reference numeral 21 denotes a lock nut, which is screwed into a threaded portion formed on the opposite end of the shaft step portion 5b of the large-diameter portion of the mounting portion 6 of the screw shaft 5, thereby connecting the two inner rings 2b to the inner ring spacer. 16 and the hub portion 19 and the shaft step portion 5b.

  Reference numeral 22 denotes a hermetic seal, which is fixed to the inner peripheral surface of the main body portion 8 of the housing 7 and the inner peripheral surface of the lid body 9 by press-fitting or the like. The seal seal 22 fixed to the inner peripheral surface of the lid body 9 is in sliding contact with the outer peripheral surface of the inner ring spacer 16 and is located on the angular ball bearing 2 side of the rotation detection plate 18, that is, on the inner side in the axial direction of the rotation detection plate 18. The lip portion is slidably brought into contact with the outer peripheral surface of the hub portion 19 to prevent dust from entering from the outside of the rotary shaft support device 1 and leakage of lubricant from the inside.

Reference numeral 23 denotes a coupling, which is attached to the end of the small diameter portion of the attachment portion 6 of the screw shaft 5 and has a function of connecting a shaft of a driving device (not shown) and the screw shaft 5.
A rotation sensor 25 detects the rotation of the detection surface by press-fitting into a rotation sensor mounting hole 26 formed through the lid 9 in the radial direction at an axial position corresponding to the rotation detection plate 18 of the lid 9. A sealing resin 27 such as an adhesive or a filler is embedded between the signal line 25a attached to face the portion 18a and connected to the outer side in the radial direction and the inner peripheral surface of the rotation sensor mounting hole 26. The rotation sensor 25 of this embodiment is a capacitance type sensor.

The rotation sensor 25 and the rotation detection plate 18 form the rotation detection mechanism of this embodiment.
Reference numeral 28 denotes a temperature sensor, which is a shaft step portion that passes through the lid body 9 in the axial direction of the screw shaft 5 between the outer ring fitting hole 11 and the outer peripheral surface of the main body 8 and fits into the outer ring fitting hole 11. Inserted into the temperature sensor mounting hole 29, which is a fine hole reaching the outer ring 2a of the angular ball bearing 2 on the 5b side, and applied around the signal line 28a drawn from the mouth of the temperature sensor mounting hole 29 on the lid 9 side. It is attached to the lid body 9 with a sealing resin 27.

  As described above, since the temperature sensor 28 of this embodiment is inserted into the main body 8 of the housing 7, the influence of the surrounding environment such as forced cooling can be made minute, and the angular ball bearing It is possible to detect the temperature in the vicinity of the outer ring 2a of the No. 2 and accurately determine the maintenance time by detecting the temperature increase of the angular ball bearing 2 due to poor lubrication such as deterioration of the lubricant, mixing of foreign matter, overload, etc. Therefore, the operation stop time of the mechanical device equipped with the rotary shaft support device 1 can be shortened.

Further, since the rotation detection plate 18 is installed outside the hermetic seal 22, even if a semi-solid or liquid lubricant is used for the lubrication of the angular ball bearing 2, the rotational energy associated with the rotation of the rotation detection plate 18 can be reduced. It becomes possible to make the loss only windage loss, and the loss torque in the detection of the rotational speed of the screw shaft 5 can be reduced.
Further, since the rotation detection plate 18 is directly fixed to the screw shaft 5 by the lock nut 21, it becomes possible to detect the actual rotation speed of the screw shaft 5, and by monitoring the difference from the rotation speed of the drive device. Abnormalities such as slippage between the inner ring 2b and the mounting portion 6 due to loosening of the lock nut 21 and poor connection due to loosening of the coupling 23, etc. can be detected immediately, and the mechanical apparatus equipped with the rotary shaft support device 1 can be detected. The occurrence of a serious failure can be prevented in advance.

Further, since the rotation sensor 25 and the temperature sensor 28 are sealed and attached with the sealing resin 27, each sensor can be securely fixed, and the prevention of intrusion of lubricating oil or processing liquid from the outside and vibration. It is possible to absorb the influence on each sensor due to, and to protect each sensor from changes in the external environment.
Further, since the outputs of the rotation sensor 25 and the temperature sensor 28 are drawn out by the signal lines 25a and 28a, the wiring process to the control panel of the mechanical device equipped with the rotary shaft support device 1 can be easily performed.

  Furthermore, since the rotation shaft support device 1 of the present embodiment incorporates the rotation sensor 25 and the temperature sensor 28 while ensuring mounting compatibility, the rotation shaft support device 1 of the present embodiment can be easily incorporated into a mechanical device. In addition to being able to be equipped, it is possible to easily shift the monitoring of the operation state of the mechanical device to automatic monitoring control, and it is possible to reduce the load on the worker by eliminating the need for regular monitoring by the worker. .

  As described above, in this embodiment, the rotation detection plate is provided outside the hermetic seal of the rotation shaft support device, the temperature sensor for detecting the temperature of the rolling bearing in the housing, and the rotation for detecting the rotation speed of the rotation shaft. By mounting the sensor, it becomes possible to accurately detect the temperature in the vicinity of the outer ring of the angular ball bearing by minimizing the influence of the ambient environment on the temperature sensor, and the temperature of the angular ball bearing due to poor lubrication, etc. The maintenance time can be accurately determined by detecting the rise, and the loss torque in detecting the rotational speed of the screw shaft can be suppressed by reducing the loss of rotational energy associated with the rotation of the rotation detection plate only to the windage. .

FIG. 3 is a half sectional view showing the rotation detection mechanism of the second embodiment.
In addition, the same part as the said Example 1 attaches | subjects the same code | symbol, and abbreviate | omits the description.
The rotary shaft support device 1 of the present embodiment has the same configuration as that of the first embodiment, but the gear-like irregularities formed in the rotation detection unit 18a of the rotation detection mechanism as shown in FIG. A rotation detection plate 18 formed on an inclined surface 31 that reduces toward the core and having a truncated cone shape is integrally formed on the outer peripheral surface of the hub portion 19. The detection surface is attached to the lid body 9 so as to face the inclined surface 31.

If comprised in this way, since the output of the electrostatic capacitance type rotation sensor 25 changes with the space | interval of the detection surface of the rotation sensor 25, and the rotation detection part 18a, the rotation detection board accompanying the axial direction displacement of the screw shaft 5 18 axial movements can be detected.
As a result, it is possible to detect a sign of a decrease in the axial rigidity due to overload, bearing wear, or the like, and it is possible to more accurately prevent the occurrence of a serious failure of the mechanical device equipped with the rotating shaft support device 1. it can.

The detection of the movement of the rotation detection plate 18 in the axial direction by the rotation sensor 25 can also be performed using the rotation detection mechanism shown in FIG.
In the rotation detection mechanism shown in FIG. 4A, the detection surface of the rotation sensor 25 is disposed opposite to one end of the rotation detection unit 18a of the disk-shaped rotation detection plate 18 similar to that of the first embodiment. The detection surface of the rotation detecting unit 18a is detected by a part of the detection surface, and the movement of the rotation detecting plate 18 in the axial direction is detected using an output that varies depending on the amount of overlap between the detection surface and the rotation detecting unit 18a. It is to detect.

  Further, the rotation detection mechanism shown in FIG. 4B has a plurality of detections penetrating in the axial direction through the rotation detection unit 18a equally arranged in the circumferential direction of the rotation detection unit 18a of the thin disk-shaped rotation detection plate 18. The detection surface of the rotation sensor 25 that is provided in the axial direction with the hole 35 is disposed oppositely, and the rotation sensor 25 is configured to detect irregularities due to the detection hole 35 of the rotation detection unit 18a. The movement of the rotation detection plate 18 in the axial direction is detected using the change in the output of the flat plate portion during the detection pulses.

As described above, even when the rotation detection mechanism shown in FIG. 4 is used, a sign of a decrease in axial rigidity due to overload, bearing wear, or the like can be detected as described above.
As described above, in this embodiment, in addition to the same effects as in the first embodiment, the rotation detection unit and the rotation sensor of the rotation detection plate change the output of the rotation sensor with respect to the axial displacement of the screw shaft. It is possible to detect the axial displacement of the screw shaft due to a decrease in axial rigidity due to overload, bearing wear, etc., and the occurrence of a serious failure of a mechanical device equipped with a rotating shaft support device Can be prevented more accurately.

In each of the above embodiments, the rolling bearing is described as an angular ball bearing. However, the rolling bearing is not limited to the above, and may be a deep groove ball bearing, a cylindrical roller bearing, a tapered roller bearing, or the like.
In each of the above embodiments, the rotation sensor has been described as being of the electrostatic capacitance type. However, the rotation sensor is not limited to the above, and the distance between the detection surface of the optical gap detection sensor or the like and the rotation detection unit is opposed to each other. Any sensor may be used as long as the output changes depending on the area.

Sectional drawing which shows the rotating shaft support apparatus of Example 1. FIG. The front view which shows the rotating shaft support apparatus of Example 1. FIG. Half sectional view showing a rotation detection mechanism of Example 2 Explanatory drawing which shows the other form of the rotation detection mechanism of Example 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotating shaft support device 2 Angular contact ball bearing 2a Outer ring 2b Inner ring 3 Ball 5 Screw shaft 5a Shaft raceway groove 5b Shaft step part 6 Mounting part 7 Housing 8 Body part 9 Cover (Outer ring presser plate)
DESCRIPTION OF SYMBOLS 10 Mounting bolt 11 Outer ring fitting hole 12 Locking part 13 Flange part 14 Stepped bolt hole 15 Press part 16 Inner ring spacer 18 Rotation detection plate 18a Rotation detection part 19 Hub part 21 Lock nut 22 Sealing seal 23 Coupling 25 Rotation sensor 25a, 28a Signal line 26 Rotation sensor mounting hole 27 Sealing resin 28 Temperature sensor 29 Temperature sensor mounting hole 31 Inclined surface 35 Detection hole

Claims (4)

In a rotating shaft support device comprising a rolling bearing having an outer ring and an inner ring, a housing for fixing the outer ring, a rotating shaft fitted to the inner ring, and a hermetic seal for sealing the rolling bearing,
The rotation shaft is provided with a rotation detection plate in which a rotation detection portion having irregularities is formed, and the rotation detection plate is disposed outside the hermetic seal,
A rotating shaft support device, wherein a temperature sensor for detecting a temperature of the rolling bearing and a rotation sensor for detecting a rotation speed of the rotating shaft by the rotation detection plate are attached to the housing. In claim 1,
The rotation shaft support device, wherein the rotation detection unit of the rotation detection plate and the rotation sensor are arranged so that the output of the rotation sensor changes with respect to the axial displacement of the rotation shaft. In claim 1 or claim 2,
The rotation shaft support device, wherein the rotation sensor is a capacitance type sensor. In any one of Claims 1 to 3,
A rotary shaft support device, wherein the rotary shaft is a screw shaft of a ball screw device.