Inspection device

Abstract

To inspect tightening torque by using the power of an appliance.SOLUTION: An inspection device 1 comprises: a socket 13 that fits to a nut 22 provided on a workpiece; a nut runner 12 that generates a turning force to the socket 13 by using the power generated by an appliance; a torque transducer 11 that calculates the rotation angle of the nut 22 on the basis of the measured rotation angle of the nut runner 12, and that measures the torque generated to the nut 22 and calculates the value of inspection torque in accordance with the calculated rotation angle of the nut 22 and the measured value of torque; and a display unit 14 that displays the value of inspection torque.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an inspection device for nut tightening. [Background technology]

[0002] In recent years, rotor assemblies used in motors for hybrid and electric vehicles have adopted an axial force fixing method in which the rotor core and shaft are tightened with a nut. However, as motors have become more powerful, the tightening torque of the nut must be high, at least 1000 N·m, in order to increase the core fixing force.

[0003] Patent Document 1 describes a method for measuring inspection torque using a nut runner. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-131331 Summary of the Invention [Problem to be solved by the invention]

[0005] As the tightening torque increases due to the increased output of motors, the inspection torque used to inspect the tightening torque also increases. Typically, an already tightened nut is further tightened and the moment the nut begins to turn, that is, the inflection point where static friction switches to kinetic friction, is used as the inspection torque.

[0006] However, when the tightening torque is high, at 1000 N·m or more, the inspection torque also needs to be 1000 N·m or more. Therefore, if a torque wrench is used to turn the nut, the wrench will be over 2m long, making it difficult for one person to do the work, and the torque wrench itself is heavy. Therefore, instead of manually tightening nuts that have already been tightened with a high torque by applying an even higher torque, it has been desirable to use an inspection tool that automatically measures the inspection torque and use the power of the equipment to perform the inspection.

[0007] The present disclosure provides an inspection device that uses the power of equipment to inspect tightening torque. [Means for solving the problem]

[0008] The inspection device according to the present disclosure comprises a socket that fits onto a nut attached to a workpiece, a nut runner that generates a rotational force in the socket using power generated by equipment, a torque transducer that calculates the rotation angle of the nut based on the measurement of the rotation angle of the nut runner and measures the torque generated in the nut, and calculates an inspection torque value according to the calculated rotation angle of the nut and the measured torque value, and a display unit that displays the inspection torque value. This allows the nut to be tightened using a nut runner that is powered by the equipment, and also allows information for calculating the inspection torque to be obtained and the inspection torque to be calculated. [Effects of the Invention]

[0009] According to the present disclosure, it is possible to provide an inspection device that inspects tightening torque by utilizing the power of equipment. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram illustrating a configuration of an inspection device according to a first embodiment. [Figure 2] FIG. 3 is a diagram showing a flow of operations of the inspection device according to the first embodiment. [Figure 3] 5 is a diagram showing a relationship between the rotation angle and torque of the nut according to the first embodiment and an example of detection of point A. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] Embodiment 1 An inspection device according to this embodiment will be described below with reference to the drawings. Fig. 1 is a diagram showing the configuration of inspection device 1. Inspection device 1 includes a torque transducer 11, a nut runner 12, a socket 13, and a display unit 14. Here, the description will be given assuming that the workpiece to be inspected using inspection device 1 is a rotor 2, which includes a rotor body 21 and a nut 22 attached to the rotor body 21.

[0012] The rotor body 21 is a rotor assembly, and the rotor core and the shaft are fixed by nuts 22. In this description, the inspection device 1 is assumed to be provided above the rotor 2, as shown in FIG.

[0013] The torque transducer 11 is a device that measures the amount of torque applied by the nut runner 12. In this example, the torque transducer 11 is disposed between the nut runner 12 provided above and the socket 13 provided below. The torque transducer 11 has the function of detecting point A, which is the inspection torque value at which the nut 22 begins to move, when the rotation of the nut runner 12 causes the socket 13 to apply a torque that tightens the nut 22.

[0014] More specifically, the torque transducer 11 has a function to measure the rotation angle of the nut runner 12 to calculate the rotation angle of the nut 22, and a function to measure the value of the torque generated in the nut 22. The torque transducer 11 also has a calculation function to automatically calculate the value of point A from a combination of the rotation angle of the nut 22 and the value of the torque generated in the nut 22. The torque transducer 11 is directly connected to the nut runner 12.

[0015] FIG. 3 is a graph showing a typical example in which the torque transducer 11 calculates the value at which the torque value reaches a maximum from the relationship between the detected torque and the rotation angle of the nut, and determines this maximum value as the value of point A.

[0016] The torque transducer 11 is also provided with a display unit 14. The display unit 14 can display the value of point A detected by the torque transducer 11, that is, the value of the inspection torque.

[0017] Nut runner 12 is a tool used when tightening nuts, and in this example, it is used to apply a rotational force to socket 13 in order to tighten nut 22. Nut runner 12 is directly connected to socket 13. Nut runner 12 is also connected to a power generating device (not shown), and receives power from the device to generate a rotational force.

[0018] The socket 13 is fitted into a nut 22 that secures the rotor body 21. That is, when the nut runner 12 receives power from the equipment and generates a rotational force, a rotational force is generated in the socket 13, and the nut 22 can be further tightened.

[0019] Next, an inspection process using the inspection device 1 and a process for calculating the inspection torque from the results of the inspection process will be described with reference to Fig. 2. Fig. 2 is a flowchart showing the inspection process and the process for calculating the inspection torque.

[0020] First, the inspection process will be described. First, the inspection device 1 is set on the rotor 2 (step S1). Specifically, in the inspection device 1, the torque transducer 11 that measures the inspection torque is directly connected to the socket 13. This socket 13 is fitted into the nut 22 that secures the rotor body 21. The torque transducer 11 is directly connected to the nut runner 12.

[0021] Next, power is received from the equipment, and a rotational force is generated in the nut runner 12 (step S2). As a result, the nut runner 12 applies the rotational force to the nut 22 via the socket 13, thereby tightening the nut 22.

[0022] At this time, the speed at which the inspection device 1 rotates the nut 22 using the socket 13 is about 1 to 20 rpm, similar to when measuring inspection torque by normal manual work. Also, the angle at which the inspection device 1 rotates the nut 22 using the socket 13 is about 1 to 10°. This is because if the nut 22 is rotated too much, it will be over-tightened.

[0023] Next, the inspection torque calculation process is performed. As shown in step S2, when the nut runner 12 rotates at a specified rotation speed and rotation angle, the nut 22 is tightened further via the socket 13. At this time, the torque transducer 11 rotates simultaneously with the nut runner 12 and the socket 13, that is, rotates together with them (step S3).

[0024] The torque transducer 11 acquires the torque at which the socket 13 tightens the nut 22 and the angle of rotation, and calculates point A, which is the inspection torque at which the nut 22 begins to move (step S4). Typically, as shown in Fig. 3, the torque transducer 11 acquires the maximum value of the torque and can determine this maximum value as the value at point A.

[0025] The display unit 14 displays the value of the inspection torque automatically calculated by the torque transducer 11 (step S5).

[0026] As a result, the nut 22 can be retightened using the nut runner 12 that operates using power from the equipment, and point A, which is the inspection torque, can be detected using the torque transducer 11 that has a function of detecting point A. Therefore, by using the inspection device 1, point A, which is the inspection torque, can be detected using the power of the equipment without requiring manpower.

[0027] The present invention is not limited to the above-described embodiment, and can be appropriately modified without departing from the spirit of the present invention. In other words, the above description has been omitted or simplified as appropriate for the sake of clarity, and a person skilled in the art can easily modify, add, or convert each element of the embodiment within the scope of the present invention. [Explanation of symbols]

[0028] 1. Inspection equipment 2 rotors 11 Torque Transducer 12 Nutrunner 13 sockets 14 Display section 21 Rotor body 22 Nut

Claims

[Claim 1] a socket that fits onto a nut provided on the workpiece; a nut runner that generates a rotational force in the socket using power generated by the equipment; a torque transducer that calculates a rotation angle of the nut based on the measurement of the rotation angle of the nut runner, measures a torque to be generated in the nut, and calculates an inspection torque value according to the calculated rotation angle of the nut and the measured torque value; A display unit that displays the inspection torque value. Inspection equipment.

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