JP5303296B2 - Torque measuring device for rotating shaft - Google Patents

Description

  The present invention relates to a torque measuring device for a rotating shaft for measuring torque acting on a rotating shaft (such as a driving shaft of a rolling facility) provided with a cross shaft joint.

  Conventionally, the torque acting on the rotating shaft is obtained by attaching a strain gauge to the rotating shaft, sending the output of the strain gauge to the fixed antenna via the rotating antenna attached to the rotating shaft, and converting this output into torque. (Patent Document 1).

JP-A-6-66653

  For example, in steel rolling equipment, if a large load (torque) is applied to the drive shaft during rolling and the torque when changing the rolling conditions for each product is known, it can be used for setting rolling conditions and maintaining rolling equipment. Therefore, it is desired to measure the torque of the drive shaft.

  In order to measure the torque acting on such a drive shaft using the torque measuring device of Patent Document 1, a strain gauge is pasted on a real shaft or pipe whose dimensions are known, and this output is transmitted by a transmitter. Then, this is received by the receiver provided at the nearest position, but the position of the transmitter greatly fluctuates due to the angle of the drive spindle and the spline sliding, so in the torque measuring device of Patent Document 1, There was a problem that measurement was not possible.

  An object of the present invention is to provide a torque measuring device for a rotating shaft that can easily perform torque measurement of the rotating shaft, which is difficult to measure using a strain gauge, using a cross joint.

  In the torque measuring device for a rotating shaft according to the present invention, a bearing cup is swingably mounted on each of the four shaft portions of the cross shaft, and a plurality of rolling elements roll between the four shaft portions and the bearing cup. An apparatus for measuring torque of a rotary shaft including a cruciform shaft joint that is movably disposed; a displacement sensor that detects a relative displacement amount between a shaft portion of the cruciform shaft and the bearing cup; And a processing means for converting the output of the displacement sensor into the torque of the rotating shaft using the correlation between the output of the displacement sensor and the torque of the rotating shaft.

  The cruciform joint is formed of, for example, bearing steel, and is slidably mounted on the cruciform shaft disposed between the flange yokes provided at the ends of the two rotating shafts, and the four shaft portions of the cruciform shaft. Bearing cups, and a plurality of rolling elements (rollers) arranged so as to be able to roll between each shaft portion and the bearing cup, and the bearing cup and the flange yoke are coupled by bolts. The two rotating shafts are coupled so that relative swinging is possible and rotation is reliably transmitted. The relative swinging of the cross shaft and the bearing cup serves as a buffer function to alleviate an impact when transmitting rotational motion from one rotating shaft to the other rotating shaft.

  Conventionally, in order to measure the torque of a rotating shaft, it is necessary to attach a strain gauge to the rotating shaft and process this output. The relative displacement between the shaft portion of the cross shaft and the bearing cup is the rotation It was considered that there was no correlation with the torque acting on the shaft. The present inventor has a correlation (proportional) between the relative displacement between the shaft portion of the cross shaft and the bearing cup reflecting the displacement (elastic displacement) of the roller, and the roller elastic displacement and the rotational torque. The present invention has been achieved by paying attention to the fact that the relative displacement between the shaft portion of the cross shaft and the bearing cup is also correlated (proportional) with the rotational torque.

  The displacement sensor and the configuration for taking out this output can be incorporated in the bearing cup as a wireless sensor unit. The wireless sensor unit is detachably inserted into the case insertion hole provided in the bearing cup in addition to the displacement sensor. And a sensor board with a built-in preamplifier and a power supply circuit, a wireless communication device as a transmission / reception means on the rotating shaft side, and a battery.

  The roller is made of, for example, bearing steel and rolls with the inner peripheral surface of the bearing cup as the outer ring raceway and the outer peripheral surface of the shaft portion of the cross shaft as the inner ring raceway, and the radial displacement (elastic displacement) is the axis of the cross shaft. This is reflected in the relative displacement between the part and the bearing cup. Accordingly, the relative displacement between the shaft portion of the cross shaft and the bearing cup is detected by a displacement sensor, and the torque acting on the rotation shaft is obtained by utilizing the correlation (proportional) between the relative displacement amount and the rotation torque. .

  For example, an eddy current sensor is suitable as the displacement sensor. However, any sensor that can measure the relative displacement between the shaft portion of the cruciform shaft and the bearing cup is a capacitance sensor, an optical sensor, a super sensor, and the like. A sound wave type, a contact type, etc. may be sufficient and the form is not limited.

  The processing means may be provided on the sensor substrate of the wireless sensor unit, may be provided in a panel computer that monitors the rotation axis, or may be provided in a personal computer connected to the panel computer.

  According to the torque measuring device for a rotating shaft of the present invention, a displacement sensor for detecting a relative displacement amount between the shaft portion of the cross shaft and the bearing cup, and a proportional relationship between the output of the displacement sensor and the torque of the rotating shaft are obtained. And a processing means for converting the output of the displacement sensor into the torque of the rotary shaft, so even if it is difficult to attach a strain gauge to the rotary shaft or install a communication device, the torque of the rotary shaft Can be measured easily.

FIG. 1 is a perspective view showing a drive shaft of a rolling equipment in which a torque measuring device for a rotating shaft according to the present invention is preferably used. FIG. 2 is a cross-sectional view showing a sensor unit which is a component of a torque measuring device for a rotating shaft according to the present invention and a bearing cup incorporating the sensor unit. FIG. 3 is a block diagram showing a hardware configuration of a torque measuring device for a rotating shaft according to the present invention. FIG. 4 is a block diagram showing a torque measuring device for a rotating shaft according to the present invention.

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

  FIG. 1 shows a part of a drive shaft (1) of a rolling facility as an example to which a torque measuring device for a rotating shaft according to the present invention is applied. The drive shaft (1) connects a rolling roller (not shown) and a driving motor, and transmits the rotation of the driving motor to the rolling roller.The roller rotating shaft (2) is connected to the rolling roller at one end. An intermediate rotary shaft (3) whose one end is coupled to the other end of the roller rotary shaft (2) via a cross joint (4), and a cross-shaft joint at the other end of the intermediate rotary shaft (3). And a motor rotating shaft coupled at one end to the drive motor at the other end. The configuration of the coupling part by the cross joint (4) is the same on the motor rotating shaft side and the roller rotating shaft (2) side, and a pair of rotating shafts (2) and (3) are interposed at these coupling ends. The cross shaft joint (4) is coupled so as to be relatively swingable.

  A flange yoke (5) having an angle of 90 ° is provided at the coupling end of one rotary shaft (2) so as to be opposed by 180 °, and the other rotary shaft (3) A flange yoke (6) having a size of 90 ° in angle is provided at the coupling end so as to face a position shifted by 90 ° from one of the rotating shafts (2) at a distance of 180 °. The cross shaft joint (4) is provided at the cross shaft (7) having four shaft parts (trunnions) (7a), and at the joint between the cross shaft (7) and each yoke (5) (6). And four cross bearings (8). Each cross bearing (8) includes a bearing cup (9) and a plurality of rollers (10) supported by the bearing cup (9) (see FIG. 2). Each flange yoke (5) (6) is provided with a female thread portion (5a) (6a), and each bearing cup (9) is provided with a bolt insertion hole (9a). At the butt end of (2), a pair of flange yokes (5) and a pair of bearing cups (9) corresponding thereto are coupled with bolts, and the butt end of the other rotating shaft (3) The pair of flange yokes (6) and the corresponding pair of bearing cups (9) are coupled by bolts so that the rotation shafts (2) and (3) transmit rotation to each other. Are combined. The cross shaft (7) and the bearing cup (9) can be relatively swung by contacting with each other via the roller (10), and from one rotating shaft (2) to the other rotating shaft (3) It plays a buffer function to alleviate the impact when transmitting rotational motion to the. Thus, by allowing the movement of the rolling roller, the impact on the drive shaft (1) is mitigated.

  For maintenance of the drive shaft (1) and setting of rolling conditions, it is desired to measure the torque acting on the drive shaft (1) during rolling. To measure this torque, at least one bearing cup (9 2) incorporates a wireless sensor unit (11) whose detailed structure is shown in FIG. 2, and wirelessly connects the wireless sensor unit (11) and the panel computer (19) as shown in FIG.

  As shown in FIG. 2, the bearing cup (9) is provided with a cross shaft storage space (9b) for storing the shaft (7a) of the cross shaft (7). The plurality of rollers (10) are arranged in the same space (9b) so as to come into contact with the outer periphery of the shaft (7a) of the cross shaft (7) and roll the inner peripheral surface of the bearing cup (9). The outer ring raceway and the outer peripheral surface of the shaft portion (7a) of the cross shaft (7) roll as an inner ring raceway. The bearing cup (9) is further provided with a case insertion hole (9c) communicating with the cross shaft storage space (9b) so as to open radially outward of the drive shaft (1). In this case insertion hole (9c), a hole for supplying grease for lubricating the rolling contact portion between the cross shaft (7) and the bearing cup (9) and (10) is diverted.

  The wireless sensor unit (11) includes a bottomed cylindrical case (12) removably inserted in a case insertion hole (9c) provided in the bearing cup (9), and a cross shaft supported by the case (12). A displacement sensor (13) for detecting the relative displacement between the shaft (7a) of (7) and the bearing cup (9), and the diameter of the inner periphery of the case (12) connected to the displacement sensor (13). A sensor board (14) disposed on the inner side in the direction, a wireless communication device (15) for taking out the output from the sensor substrate (14), and a bottomed cylindrical shape supporting the wireless communication device (15). A communication device support member (16), a battery (17) for supplying power to the sensor substrate (14) and the wireless communication device (15), and a resin seal member (18) for closing the opening of the communication device support member (16) ).

  A shaft hole (7b) concentric with the case insertion hole (9c) is formed in each shaft portion (7a) of the cross shaft (7), and is connected to each other inside the cross shaft joint (4). The case (12) has a radially inner portion inserted into the shaft hole (7b), and the displacement sensor (13) is attached to the case (12) so as to face the inner wall surface of the shaft hole (7b). ing. Thereby, the displacement sensor (13) measures the relative distance between the shaft portion (7a) of the cross shaft (7) and the bearing cup (9) by measuring the distance from the inner wall surface of the shaft hole (7b). Is detected.

  The sensor substrate (14) includes a preamplifier that generates a sensor detection signal by A / D converting the detection signal from the displacement sensor (13), and a power supply circuit that appropriately distributes and supplies the direct current from the battery (17) to each part. I have.

  The wireless communication device (15) includes a wireless circuit board (15a) having a memory for holding data such as a transmission / reception circuit and a program used in the transmission / reception circuit, and an antenna (15b) installed on the wireless circuit board (15a). The battery (17) or the like is disposed at a position close to the opening of the case (12) so that the battery (17) or the like does not become a radio wave obstacle.

  As shown in FIG. 3, the wireless sensor unit (11) outputs the output from the displacement sensor (13) via the wireless communicator (15) to the wireless communicator of the panel computer (19) provided at the site of the rolling equipment. Send to (21). The panel computer (19) is connected to a personal computer (20) installed in a monitoring room away from the rolling equipment.

  When the drive shaft (1) rotates, the cross shaft (7) and the bearing cup (9) exert a force through the roller (10), and the roller (10) is displaced in the radial direction, The displacement of 10) is reflected in the relative displacement between the shaft portion (7a) of the cross shaft (7) and the bearing cup (9). The displacement sensor (13) detects the relative displacement between the shaft part (7a) and the bearing cup (9) by measuring the distance from the inner wall surface of the shaft hole (7b). The result is transmitted to the panel computer (19). Since the wireless communicator (15) is built in the bearing cup (9), the two drive shafts (1) are in close contact like the drive shaft for rolling equipment, and the cross shaft joint (4) is outside. Even when there is no gap, the output of the displacement sensor (13) can be easily taken out.

  FIG. 4 is a block diagram of a torque measuring device for a rotating shaft according to the present invention.

  In the figure, a torque measuring device for a rotating shaft includes the wireless sensor unit (11) and a control device (22) connected to the wireless sensor unit (11) via a wireless communication device (21).

  The control device (22) includes a communication control means (23) provided in the panel computer (19), a processing means (24) and a storage means (25) provided in the personal computer (20).

  Torque waveform of drive shaft (1) (Rotating shaft (2) (3) with cross joint (4)) and waveform detected by displacement sensor (13) (displacement sensor (13) and shaft hole (7b) It is confirmed that the distance from the inner wall of the shaft = the displacement waveform of the relative displacement between the shaft part (7a) of the cross shaft (7) and the bearing cup (9) is in a proportional relationship as shown in A of FIG. Has been.

  When a displacement measurement command is sent from the communication control means (23) of the control device (22) to the wireless sensor unit (11) via the wireless communication device (21), the wireless sensor unit (11) enters the displacement measurement mode and the displacement is detected. The relative displacement between the shaft part (7a) of the cross shaft (7) detected by the sensor (13) and the bearing cup (9) is input to the sensor board (14), which is the wireless communication device (15). It is transmitted to the control device (22) via (21). The storage means (25) of the control device (22) has a correlation between the torque waveform of the drive shaft (1) and the displacement waveform of the relative displacement between the shaft portion (7a) of the cross shaft (7) and the bearing cup (9). The relationship is stored, and the processing means (24) converts the output of the displacement sensor (13) into the torque of the drive shaft (1) based on this relationship.

  Thus, according to the torque measuring device for the rotating shaft, it is possible to measure the torque of the drive shaft (1), which is difficult to measure using a strain gauge. The wireless sensor unit (11) can be detachably attached to the existing drive shaft (1), whereby the torque of the existing drive shaft (1) can be easily measured. This torque measuring device can also be used for measuring the torque of a drive shaft assembled to a railway vehicle.

  The torque measuring device has a configuration similar to that of a known drive shaft damage diagnosis device, and drive shaft damage diagnosis can be performed using the torque measurement device. That is, torque is obtained in the processing means (24) from the output of the displacement sensor (13), and by detecting how much the current output waveform of the displacement sensor (13) has changed from the normal waveform. The separation state of the raceway surface of the cross shaft (7) can be detected. For example, by adding frequency analysis means such as FFT and inverse FFT to the control device (22) of the torque measuring device, the cross shaft Damage (peeling) of the joint (4) can be detected.

(2) (3) Rotating shaft
(4) Cross shaft coupling
(7) Cross axis
(7a) Shaft
(9) Bearing cup
(10) Roller (rolling element)
(13) Displacement sensor
(24) Processing means

Claims (1)

  A bearing cup is swingably mounted on each of the four shaft portions of the cross shaft, and a cross shaft joint is provided between the four shaft portions and the bearing cup. An apparatus for measuring the torque of the rotating shaft, comprising: a displacement sensor for detecting a relative displacement amount between the shaft portion of the cross shaft and the bearing cup; an output of the displacement sensor and a torque of the rotating shaft; A rotating shaft torque measuring device comprising: processing means for converting the output of the displacement sensor into the rotating shaft torque using the correlation.

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