JPH0575521U - DUT drive joint - Google Patents

Abstract

(57) [Summary] [Purpose] When the chuck holes of the attachment are fitted to the multiple tightening bolt heads protruding from the rotating shaft of the non-test machine, and the machine under test is rotated by the rotation of the attachment. Make sure that the torque in the loosening direction does not act on the bolt due to the impact force on the bolt head. A contact surface 10a of the chuck hole, which comes into contact with a bolt head 5a fitted into a chuck hole 10 of the attachment when the attachment 4 is rotated, has a contact surface 10a of the chuck hole, and the direction of the force acting on the bolt is the tightening direction of the bolt. Was formed only in a range equal to.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a device under test driving joint that connects a device under test and a driving device.

[0002]

[Prior Art]

 Generally, when performing a rotation test of a device under test such as an engine, the hexagonal head of a fastening bolt such as a flywheel is used to connect the device under test and the drive device.

In FIG. 3, reference numeral 1 is an engine as a device under test, and a flywheel 2 connected to a crankshaft of the engine 1 is provided with an attachment 4 rotated by a drive device 3 constituting the testing machine. It is adapted to be engaged. That is, as shown in FIG. 4, the attachment 4 is fitted to the head portion of the tightening bolt 5 at a position corresponding to the plurality of tightening bolts 5 that connect the flywheel 2 to the crank shatter. A plurality of chuck holes 6 in the shape of round holes are arranged in the circumferential direction. By fitting the chuck holes 6 into the hexagonal heads 5a of the tightening bolts 5, the attachment 4 and the flywheel 2 are attached. The connection is made.

[0004]

[Problems to be solved by the device]

 However, since a gap is always required between the hexagonal head 5a of the bolt 5 and the chuck hole 6, when the attachment 4 is suddenly rotated, the bolt 5 always vibrates and an impact load is applied. The force applied to the bolt is a tangential force at the contact point between the bolt 5 and the inner surface of the chuck hole 6, and the position to which the force is applied differs depending on the angular position of the bolt.

That is, in FIG. 5, when the hexagonal head 5 a of the bolt 5 is in the solid line position with respect to the chuck hole 6, a force F 1 or F 1 ′ acts on the bolt 5, and in the case of the dotted line position, The force of F2 or F2 'acts. Therefore, when the tightening direction of the bolt is the arrow R direction and the force of F2 and F2 'is applied to the bolt 5, a torque in the loosening direction acts on the bolt 5 and the bolt may loosen. However, there is a problem in that a limit check must be carried out after each engine rotation test.

In view of the above points, the present invention has an object to provide a joint for driving a device under test that uses a tightening bolt, in which the loosening of the tightening bolt as described above does not occur. To do.

[0007]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention fits chuck holes of an attachment to a plurality of tightening bolt heads protruding from a rotating shaft portion of a device under test, and operates the device under test by rotating the attachment. , In the joint for driving the DUT to be tested, the force exerted on the bolt by the contact surface of the chuck hole that comes into contact with the bolt head fitted in the chuck hole of the attachment when the attachment rotates It is characterized in that it is formed only in the range where the direction of the bolt is the same as the tightening direction of the bolt, and in other areas the chuck hole and the bolt are not in contact with each other.

[0008]

[Action]

 A tangential force acts on the bolt at the contact point between the bolt and the inner surface of the chuck hole, but this contact occurs only in the area where the direction of the force acting on the bolt is equal to the tightening direction of the bolt. A force only in the tightening direction acts on the bolt, which prevents the bolt from loosening.

[0009]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 is a vertical cross-sectional front view of an attachment 4 in the joint of the present invention, in which a surface of the attachment 4 facing a driven wheel side, which is a driven portion, faces a plurality of fastening bolts. At the position, a plurality of chuck holes 10 slightly larger than the maximum diameter of the hexagonal head 5a of the bolt are provided in the circumferential direction.

By the way, A and B are points at which the circle connecting the centers of the square bolts 5 and the inner circumference of the chuck hole 10 intersect (FIG. 2), and the intersection of the diameter of the attachment 4 and the inner circumference of the chuck hole 10 is defined. Is O, O ', the outside of the circle on the front side with respect to the rotation direction of the attachment 4, that is, the range of A-O, and the circle on the front side with respect to the rotation direction of the attachment 4 are within the circle. The contact surfaces 10a and 10b with the bolt are formed only on one side, that is, the area B-O ', and the notches 11a and 11b are formed on the other areas, and the hexagonal head 5a contacts the inner surface of the chuck hole 10. I try not to.

When the attachment 4 rotates in the direction of the arrow in FIG. 2 and the bolt head 5a vibrates, the bolt head 5a always comes into contact with only the contact surfaces 10a and 10b of the chuck hole 10 of the attachment 4. However, the impact load is only the arrows F1 and F1 'in FIG. 2, and the force applied to the tightening bolt is always in the tightening direction as shown in FIG. 2 regardless of the position of the bolt head 5a in the rotational direction. It does not generate a loosening torque on the bolt, and the bolt is not loosened by the impact.

The shapes of the chuck hole 10 and the notches 11a and 11b in FIGS. 1 and 2 are such that they can be machined only by a drill and an end mill, and the point where a force in the loosening direction is applied is eliminated. Considering only that, the shape of the notch can be various shapes.

[0014]

[Effect of the device]

 As described above, in the present invention, the engaging surface of the chuck hole, which comes into contact with the bolt head fitted in the chuck hole of the attachment when the attachment is rotated, has the direction of the force acting on the bolt due to the contact. Since it is formed only in the range where the bolt tightening direction is equal to the bolt tightening direction, even if an impact force is applied to the bolt due to the vibration of the bolt, the impact force direction is always only in the bolt tightening direction and the bolt loosens. There is no need to do this, and there is no need to perform a limit check after each test.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of an attachment of the present invention.

FIG. 2 is an explanatory view of the operation of the present invention.

FIG. 3 is a diagram showing a state in which an engine and a test apparatus are connected by a joint.

FIG. 4 is a front view of a conventional joint.

FIG. 5 is an operation explanatory view of a conventional joint.

[Explanation of symbols]

 2 Flywheel 3 Drive device 4 Attachment 5 Bolt 5a Hexagonal head 10 Chuck hole 10a Contact surface 11a, 11b Notch

Claims (1)

[Scope of utility model registration request] 1. An object to be tested, in which chuck holes of an attachment are fitted into a plurality of tightening bolt heads protruding from a rotating shaft of the apparatus to be tested, and the operation of the apparatus to be tested and the test are performed by rotation of the attachment. In the drive joint, when the attachment is rotated, the engaging surface of the chuck hole that comes into contact with the head of the bolt fitted in the chuck hole of the attachment has the engagement surface of the chuck hole whose direction is the tightening direction of the bolt. A joint for driving a device under test, characterized in that the chuck hole and the bolt are not in contact with each other in other ranges than the above.