JP2005249594A - Measuring method for load on rolling element and bearing for measuring load - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a measuring method for load on a rolling element and a bearing for measuring the load capable of accurately measuring the load on the rolling element at the bearing which contact angle varies when an axial load is acting on. <P>SOLUTION: In a rolling inner wheel 13 or an outer wheel 11, a notch groove 16 whose groove bottom surface angle 17 is set rectangular to the line 18 of mean value α1 of an initial contact angle α0 and a contact angle α2 at the time of maximum axial loading, is formed. On the groove bottom surface 17 of the notched groove 16, two sheets of 2-axis strain gauges 19, 19 are pasted. The axial direction position for pasting the strain gauges 19, 19 is a position evenly split in the axial direction for the mean value line 18. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a rolling element load measuring method and a load measuring bearing. More specifically, the present invention relates to a rolling element that measures the load of a rolling element of a bearing whose contact angle varies depending on the magnitude of the axial load when an axial load is applied. The present invention relates to a moving body load measuring method and a load measuring bearing.

  Bearings such as the main bearing of a traveling speed reducer receive a large moment load and are often used with two bearings preloaded, and the rolling fatigue life of the bearing becomes a problem. Since the rolling fatigue life of a bearing is affected by the setting of the preload and how the load is applied (load distribution to the two bearings, etc.), the actual rolling element load distribution is grasped, and the amount of preload is set so that the life is extended. It is important to set Therefore, a method for accurately measuring the rolling element load and its distribution is necessary.

As an example of a conventional rolling element load measuring method, one using a tapered roller bearing is known (for example, see Patent Document 1). As shown in FIG. 8, the rolling element load measuring method disclosed in Patent Document 1 forms a notch 4 in the inner ring 2 or the outer ring 3 of the tapered roller bearing 1. The bottom surface 5 of the notch 4 is a straight line L-L that is parallel to the contact line MM with the inner ring 2 or the outer ring 3 and the width of the strain gauge 7 bonded to the bottom surface 5 of the notch 4. The width of the roller 6 is appropriately widened. Thereby, even when the inner ring 2 or the outer ring 3 is inclined and the load acting line applied to the tapered roller bearing 1 is deviated from the center of the roller 6, the load applied to the bearing 1 is increased to the magnitude of the load acting on the roller 6. It can be detected as a proportional strain amount. Then, it is possible to accurately know the thrust load and radial load actually applied to the tapered roller bearing 1 during the rotation of the bearing based on the detected strain amount.
Japanese Patent Publication No.52-10027 (page 1-3, Fig. 3)

  By the way, in the above-mentioned rolling element load measuring method, the tapered roller bearing 1 is measured, and the contact angle does not change even when a load is applied. Therefore, the strain gauge 7 is simply arranged on the bottom surface 5 of the notch 4. It was. However, when an axial load is applied as in the case of an angular ball bearing, the contact angle changes depending on the magnitude of the load.

  The present invention has been made in view of the above circumstances, and the object thereof is a rolling element load measuring method capable of accurately measuring the load load of a rolling element of a bearing in which an axial load is applied and the contact angle changes. And providing a load measuring bearing.

The above object of the present invention is achieved by the following configurations.
(1) The bearing has an inner ring, an outer ring, and a plurality of rolling elements arranged between the inner ring and the outer ring, and the bearing angle changes according to the magnitude of the axial load when an axial load is applied. A rolling element load measuring method for measuring a load of a moving object,
In the rotating inner ring or outer ring, a notch groove is formed in which the angle of the groove bottom surface is set to be perpendicular to the median line between the initial contact angle and the contact angle at the time of maximum axial load,
Two biaxial strain gauges are affixed to the groove bottom surface of the notch groove, and the axial position where the strain gauge is affixed is a position that is equally distributed in the axial direction with respect to the median line. The rolling element load measuring method according to claim 1.
(2) The rolling element load measuring method according to (1), wherein the strain amount detected by the strain gauge is transmitted as a signal using a wireless system or a slip ring.
(3) The bearing includes an inner ring, an outer ring, and a plurality of rolling elements disposed between the inner ring and the outer ring, and the bearing angle changes according to the magnitude of the axial load when an axial load is applied. A load measuring bearing for measuring a load of a moving body,
The rotating inner ring or outer ring is formed with a notch groove in which the angle of the groove bottom surface is set to be perpendicular to the median line between the initial contact angle and the contact angle at the time of maximum axial load. ,
Two biaxial strain gauges are affixed to the groove bottom surface of the notch groove, and the axial position where the strain gauge is affixed is a position that is equally distributed in the axial direction with respect to the median line. A load measuring bearing.

  According to the rolling element load measuring method of the present invention, the groove bottom surface of the notch groove is set at a right angle to the median line of the initial contact angle and the contact angle at the time of maximum axial load. Since the axial position of the two biaxial strain gauges affixed to the groove bottom surface of the groove is a position that is evenly distributed in the axial direction with respect to this median line, the two positions where the strain gauges are affixed Within this range, the contact position when an axial load is applied is always arranged. Therefore, the strain due to the axial load can be detected from any of the two strain gauges, and measurement with high accuracy can be performed. Thereby, the load acting on the bearing can be grasped, and a bearing specification suitable for the load condition can be designed.

  In addition, according to the rolling element load measuring method of the present invention, since the amount of strain detected by the strain gauge is transmitted using a wireless system or a slip ring, the rolling element load on the rotating wheel side is measured. Thus, the rolling element load and the load area range at each position in the load area can be known, which is suitable for examining how the load is applied.

  According to the load measuring bearing of the present invention, the groove bottom surface of the notch groove is set at right angles to the median value of the initial contact angle and the contact angle at the time of maximum axial load, and the groove of the notch groove Since the axial positions of the two biaxial strain gauges attached to the bottom surface are equally distributed in the axial direction with respect to the median line, they are within the range of the two positions where the strain gauges are attached. The contact position when an axial load is applied is always arranged. Therefore, by using the load measuring bearing as described above, the strain amount due to the axial load load can be detected from any of the two strain gauges, and the measurement can be performed with high accuracy.

  Hereinafter, a rolling element load measuring method and a load measuring bearing according to an embodiment of the present invention will be described in detail with reference to the drawings.

  1 is a cross-sectional view showing a load measuring bearing used in a rolling element load measuring method according to an embodiment of the present invention, FIG. 2 is a front view of the load measuring bearing shown in FIG. 1, and FIG. 3 is a load shown in FIG. FIG. 4 is a side view of a rolling element load measuring tester using a measuring bearing, FIG. 4 is a strain waveform diagram when the rolling element passes through a notch groove, and FIG. 5 is a rolling diagram using the load measuring bearing shown in FIG. FIG. 6 is a block diagram when a wireless system is used as a measurement system for a moving body load measurement method. FIG. 6 is a block diagram when a slip ring is used as a measurement system for a rolling element load measurement method performed using the load measurement bearing shown in FIG. FIG. 7 is a cross-sectional view showing a modification of the load measuring bearing.

  As shown in FIG. 1, a load measuring bearing 10 according to an embodiment of the present invention is an angular ball bearing, and includes an outer ring 11 that is a counter bore type having an outer ring raceway surface 12 on an inner peripheral surface, and an outer peripheral surface. A ball which is a counter bore type having an inner ring raceway surface 14 and a plurality of rolling elements incorporated in a circumferential direction with a contact angle between the outer ring raceway surface 12 and the inner ring raceway surface 14. 15 and a cage (not shown) that holds the plurality of balls 15 in the circumferential direction at a predetermined interval.

  As shown in FIGS. 1 and 2, a notch groove 16 having a width of the circumferential length L <b> 1 is formed at one location on the outer diameter surface of the outer ring 11. In the notch groove 16, the angle of the groove bottom surface 17 is set to be perpendicular to the line 18 having a median value α1 between the initial contact angle α0 when no axial load is applied and the contact angle α2 when the maximum axial load is applied. Yes. Two biaxial strain gauges 19 and 19 are attached to the central portion in the circumferential direction of the groove bottom surface 17 of the notch groove 16. The strain gauges 19 and 19 are set at positions where the axial positions are equally distributed in the axial direction with respect to the line 18 having a median value α1 between the initial contact angle α0 and the contact angle α2 when the maximum axial load is applied. Yes.

  As shown in FIG. 3, the two load measuring bearings 10, 10 configured in this way are installed in a rolling element load measuring test machine 50, and load loads of the rolling elements 15, 15 of the bearings 10, 10 are reduced. Measured. The rolling element load measuring and testing machine 50 includes a housing 51, a fixed shaft 52, an L-shaped pedestal 53, a drive shaft 54, a load bearing 55, a load cell 56, and a load device 57.

  The drive shaft 54 includes a timing pulley 58 that spans a timing belt (not shown) connected to a drive motor (not shown) at one end, and the drive shaft 54 is connected to the other end by the drive motor. Rotates with the housing 51 fixed to the

  The load bearing box 55 includes a pair of tapered roller bearings. Inner rings 59 and 59 are fitted on the drive shaft 54, and outer rings 60 and 60 are fitted on the load bearing box 55. The load bearing box 55 is coupled to a load device 57 via a load cell 56. The load device 57 is disposed on the L-shaped pedestal 53 and incorporates a hydraulic cylinder 62.

  The load measuring bearings 10 and 10 have inner rings 13 and 13 fitted on a fixed shaft 52 fixed to an L-shaped pedestal 53, and outer rings 11 and 11 fitted on a housing 51, and rolling element load measurement is performed with a rear combination. Arranged on the testing machine 50.

  In the rolling element load measuring and testing machine 50 configured as described above, a combined load obtained by combining the radial load and the axial load is loaded from the load device 57 to the load bearing box 55 via the load cell 56, and the housing is driven by the drive motor. By rotating 51 together with the drive shaft 54, the outer rings 11, 11 of the load measuring bearings 10, 10 are rotated while receiving a combined load. By rotating the outer rings 11 and 11 of the load measuring bearings 10 and 10, when the notch groove 16 of the outer ring 11 passes through the ball 15, the notch groove 16 associated with the load applied to the ball 15 is changed. The amount of strain is detected by strain gauges 19 and 19. That is, as shown in FIG. 4, every time the ball 15 passes through the notch groove 16, a peak strain amount is detected.

  The detected strain amount is transmitted to the measuring device 70 (shown in FIG. 5). As shown in FIG. 5, the measurement device 70 is a wireless system, and a rotation pulse detection for detecting the number of rotations of a transmitter 71, a transmission antenna 72, a reception antenna 73, a receiver 74, and a housing 51. It comprises an instrument 75, an amplifier 76, a data recorder 77, and a monitor device 78. The transmitter 71 and the transmission antenna 72 are mounted on the housing 51.

  The measuring device 70 detects the amount of strain as a voltage signal by the rolling element load detection bridge incorporating the strain gauges 19, 19, is converted into a radio signal by the transmitter 71, is transmitted from the transmission antenna 72, and passes through the reception antenna 73. Is received by the receiver 74 and the amount of distortion is measured. Then, the distortion amount measured by the receiver 74 is captured and stored in the data recorder 77 and displayed as an image by the monitor device 78. At this time, since the rotational speed data is supplied to the data recorder 77 and the monitor device 78 after the electric signal generated in the rotational pulse detector 75 is amplified by the amplifier 76, the equivalent load is based on the amount of strain with respect to the rotational speed. Can be calculated to calculate the rolling element load. Thereby, it is possible to obtain a rolling element load that is consistent with a calibration diagram that is a relationship between the rolling element load and strain measured in advance.

  As shown in FIG. 6, a measuring device 80 using a slip ring 81 may be used instead of the measuring device 70 of the wireless system shown in FIG. The measuring device 80 includes a slip ring 81, a dynamic strain meter 82, a rotation pulse detector 83, an amplifier 84, a data recorder 85, and a monitor device 86.

  The measuring device 80 detects the amount of strain as a voltage signal by a rolling element load detection bridge incorporating the strain gauges 19, 19, and is transmitted to the dynamic strain meter 82 via the slip ring 81. Then, the strain amount measured by the dynamic strain meter 82 is captured and stored in the data recorder 85 and is displayed as an image by the monitor device 86. At this time, since the rotational speed data is supplied to the data recorder 85 and the monitor device 86 after the electric signal generated in the rotational pulse detector 83 is amplified by the amplifier 84, the equivalent load is based on the amount of strain with respect to the rotational speed. Can be calculated to calculate the rolling element load. Even in this case, it is possible to obtain a rolling element load that is consistent with a calibration diagram that is a relationship between the rolling element load and strain measured in advance.

  Next, a modification of the load measuring bearing according to the present embodiment will be described with reference to FIG.

  As shown in FIG. 7, the load measuring bearing 90 of this modification is a self-aligning roller bearing, and includes an outer ring 91 having a spherical outer ring raceway surface 92 on the inner peripheral surface and two rows on the outer peripheral surface. An inner ring 93 having inner ring raceway surfaces 94, 94, and a plurality of double-row rolling elements that are rotatably incorporated between the outer ring raceway surface 92 and the inner ring raceway surfaces 94, 94 in the circumferential direction. And a retainer 96 that holds a plurality of rows of rollers 95 in a rollable manner.

  On the outer diameter surface of the outer ring 91, notched grooves 97 and 97 are formed at two symmetrical positions corresponding to the double-row rollers 95 and 95. In the notched grooves 97, 97, the angle of the groove bottom surfaces 98, 98 is set to be perpendicular to the line 100 having a median value α1 between the initial contact angle α0 and the contact angle α2 when the maximum axial load is applied. Two biaxial strain gauges 99 and 99 are attached to the groove bottom surfaces 98 and 98, respectively. The strain gauges 99 and 99 are set so that their axial positions are equally distributed in the axial direction with respect to the line 100 having a median value α1 between the initial contact angle α0 and the contact angle α2 when the maximum axial load is applied. Yes.

  The load measuring bearing 90 of this modification is used by being assembled in the rolling element load measuring test machine 50 in the same manner as the load measuring bearing 10 described above, and has the same functions and effects as the load measuring bearing 10. Can do.

  As described above, according to the rolling element load measuring method, the groove bottom surface 17 of the notch groove 16 is perpendicular to the line 18 having a median value α1 between the initial contact angle α0 and the contact angle α2 when the maximum axial load is applied. The positions of the two biaxial strain gauges 19 and 19 attached to the groove bottom surface 17 of the notch groove 16 are equally distributed in the axial direction with respect to the median line 18. For this reason, the contact position when the axial load is applied is always arranged within the range of the two positions where the strain gauges 19, 19 are attached. Therefore, the strain due to the axial load can be detected from any of the two strain gauges 19 and 19, and measurement with high accuracy can be performed. Thereby, the load acting on the bearing can be grasped, and a bearing specification suitable for the load condition can be designed.

  Further, according to the rolling element load measuring method, since the detected strain amount is transmitted by the measuring device 70 using the wireless system or the measuring device 80 using the slip ring 81, the rolling element on the rotating wheel side is used. Since the load can be measured and the rolling element load and the load area range at each position within the load area can be known, it is suitable for examining how the load is applied.

  Further, according to the load measuring bearings 10, 90, the groove bottom surfaces 17, 98, 98 of the notched grooves 16, 97, 97 have a median value α1 between the initial contact angle α0 and the contact angle α2 when the maximum axial load is applied. The axes of two biaxial strain gauges 19, 19, 99, 99 affixed to the groove bottom surfaces 17, 98, 98 of the notched grooves 16, 97, 97 Since the directional position is a position that is equally distributed in the axial direction with respect to the line of the median value α1 of the initial contact angle α0 and the contact angle α2 when the maximum axial load is applied, the strain gauges 19, 19, 99, 99 The contact position when an axial load is applied is always placed within the range of the two positions where the mark is pasted. Therefore, by using such load measuring bearings 10, 90, strain due to the axial load can be detected from any of the two strain gauges 19, 19, 99, 99, and measurement with high accuracy can be performed.

In addition, this invention is not limited to each embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.
Although the rolling bearing of this embodiment is an outer ring rotation, in the case of an inner ring rotation, a notch groove is provided on the inner surface of the inner ring, and two biaxial strain gauges are attached to the groove bottom surface to rotate the inner ring. Thus, the rolling element load can be measured.

It is sectional drawing which shows the bearing for load measurement used for the rolling element load measuring method of one Embodiment which concerns on this invention. FIG. 2 is a front view of the load measuring bearing shown in FIG. 1. It is a partially broken side view of the rolling element load measuring test machine using the load measuring bearing shown in FIG. It is a distortion waveform figure when a rolling element passes the notch groove. It is a block diagram at the time of using a radio | wireless system for the measurement system of the rolling element load measuring method performed using the load measuring bearing shown in FIG. It is a block diagram at the time of using a slip ring for the measuring system of the rolling element load measuring method performed using the bearing for load measurement shown in FIG. It is sectional drawing which shows the modification of the load measuring bearing. It is sectional drawing which shows the bearing for load measurement used for the conventional rolling element load measuring method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10,90 Load measuring bearing 11,91 Outer ring 12,92 Outer ring raceway surface 13,93 Inner ring 14,94 Inner ring raceway surface 16,97 Notch groove 17,98 Groove bottom surface 19,99 Strain gauge 70,80 Measuring device

Claims (3)

Load of the rolling element of the bearing having an inner ring, an outer ring, and a plurality of rolling elements disposed between the inner ring and the outer ring, the contact angle of which varies depending on the magnitude of the axial load when receiving an axial load. A rolling element load measuring method for measuring a load,
In the rotating inner ring or outer ring, a notch groove is formed in which the angle of the groove bottom surface is set to be perpendicular to the median line between the initial contact angle and the contact angle at the time of maximum axial load,
Two biaxial strain gauges are affixed to the groove bottom surface of the notch groove, and the axial position where the strain gauge is affixed is a position that is equally distributed in the axial direction with respect to the median line. The rolling element load measuring method according to claim 1.   The rolling element load measuring method according to claim 1, wherein the amount of strain detected by the strain gauge is transmitted using a wireless system or a slip ring. Load of the rolling element of the bearing having an inner ring, an outer ring, and a plurality of rolling elements disposed between the inner ring and the outer ring, the contact angle of which varies depending on the magnitude of the axial load when receiving an axial load. A load measuring bearing for measuring a load,
The rotating inner ring or outer ring has a notch groove in which the angle of the groove bottom surface is set to be perpendicular to the median line between the initial contact angle and the contact angle at the time of maximum axial load. ,
Two biaxial strain gauges are affixed to the groove bottom surface of the notch groove, and the axial position where the strain gauge is affixed is a position that is equally distributed in the axial direction with respect to the median line. A load measuring bearing.

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