JPH0448570B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Field of Application) The present invention relates to an automatic screw adjustment device for a guide pole for running a VTR tape, for example.

(Prior technology) To run a VTR tape, it is guided by a guide pole, but this guide pole is
It is fixed to the VTR frame. Fixing the guide pole requires adjustment and is generally done manually, which has the drawback of low productivity. Therefore, there is a demand for the development of an automatic screw adjustment device that automates the adjustment work.

In conventional automatic screw adjusting machines, a driver bit is directly connected to the rotating shaft of a drive motor. Therefore, if there is a slight misalignment between the driver bit and the screw due to lack of flexibility between the driver bit and the screw, the driver bit may not fit into the groove provided in the screw head. Even when the screws are barely fitted, a lateral external force is applied to the screws, causing deformation of the guide pole mounting portion, resulting in disturbances in the tape signal and the drawback that it takes too much time to adjust the guide pole mounting.

(Problems to be Solved by the Invention) As mentioned above, in the conventional automatic screw adjusting machine, the driver bit is directly connected to the rotating shaft of the drive motor, so it is not possible to correct the misalignment between the driver bit and the screw. This causes extra external force to be applied to the screw. As a result, the guide pole is deformed, causing disturbances in the tape signal. Therefore, in the past, it was necessary to repeatedly perform the adjustment, which was extremely troublesome.

This invention was made in view of the above circumstances, and its purpose is to automatically engage the driver bit with the screw so that the driver bit rotates without applying any extra external force to the screw. The object of the present invention is to provide an adjustable automatic screw adjusting device.

[Structure of the Invention] (Means and Effects for Solving the Problems) In order to achieve the above object, the present invention provides a motor that is connected to the rotating shaft of the motor in the axial direction and is provided with a universal joint, a spline, and a coupling in the middle. A rotation transmission shaft is provided which is movable vertically and in the radial direction, and a driver bit is connected to the rotation transmission shaft in the axial direction, and a vertically disposed vertically movable and coaxially engaged with the driver bit. A tapered shaft portion is provided at the upper end, and a tapered recess is provided at the lower end, the inner circumferential surface of which comes into contact with the head of the screw to correct misalignment between the tip of the driver bit and the screw. Install a guide block,
Further, a positioning plate is provided which is provided with a tapered hole into which the tapered shaft portion of the guide block is fitted so as to be freely retractable.

Then, by supporting the positioning plate so as to be able to move up and down, and lowering the positioning plate using a cylinder, the tapered recess of the guide block is brought into contact with the head of the screw, and the tip of the driver bit is screwed into the screw. The reason is that it is introduced into the groove.

(Example) Hereinafter, an example of the present invention will be described with reference to the accompanying drawings. 1 in the figure is the base of this automatic screw adjustment device. A motor 2 is provided above the base 1. A rotating shaft 3 of this motor 2 is supported by a base 1 via bearings 4, 4.
A universal joint 5 is provided between an upper rotation shaft 3a and a lower rotation shaft 3b, which constitute a rotation transmission shaft. Further, the lower rotating shaft 3b is connected to the rotating shaft 3c via a ball spline 6 as a spline. The rotating shaft 3c can move vertically, but rotates integrally with the rotating shaft 3b. Further, the rotating shaft 3c is connected to the driver bit 8 via a coupling. The hatched lower end 8a of this driver bit 8 has a screw 9.
The screw 9 is fitted into a groove 11 provided in a screw head 10, and the screw 9 is screwed into, for example, a frame 12 of a VTR. A cylindrical guide block 13 is fitted on the outside of the driver bit 8 to guide the vertical movement of the driver bit 8 and to align the axis of the driver bit 8 with the axis of the screw 9. It's summery. That is, the diameter of the lower end of the driver bit 8 is made larger than that of the upper end, and a stepped portion 8b is provided. Further, the outer guide block 13 is provided with a through hole having a stepped portion consisting of a small diameter hole 13a and a large diameter hole 13b along the center line. The diameter of the lower end side of the driver bit 8 is formed to be thicker than the small diameter hole 13a of the guide block 13, so that the guide block 13 does not slip out, and the driver bit 8 is guided by the large diameter hole 13b of the guide block 13. It's becoming like that. A tapered recess 14 is formed inside the lower end of the guide block 13 and comes into contact with the screw head 10 of the screw 9 to align the axis of the driver bit 8 with the axis of the screw 9. There is. Further, a tapered shaft portion 15 is provided at the upper end of the guide block 13.

On the other hand, a cylinder mounting member 1 is provided on the bottom surface of the base 1.
6 is fixed, and this cylinder mounting member 16 is provided with an air cylinder 17 as a first cylinder. The spindle 18 of this air cylinder 17 passes through the cylinder mounting member 16 and extends downward. A positioning plate 19 is fixed to the lower end of the spindle 18. This positioning plate 19 is provided with a tapered hole 20 having a taper that matches the tapered shaft portion 15 formed at the upper end of the guide block 13. When the positioning plate 19 is lowered, the tapered hole 20 is inserted into the guide block 13. The guide block 13 is fitted into the formed tapered shaft portion 15 so that the center line of the guide block 13 coincides with the center line of the driver bit 8. That is, the distance between the center line of the tapered hole 20 and the center line of the spindle 18 is equal to the distance between the center line of the spindle 18 and the center line of the driver bit 8.

Further, another cylinder mounting member 21 is fixed to the lower surface of the base 1, and an air cylinder 22 is mounted to this cylinder mounting member 21. An operating arm 24 is fixed to the lower end of the spindle 23 of the air cylinder 22 as the second cylinder, and the tip of the operating arm 24 is in contact with the flange 7a of the coupling ring 7, so that the air cylinder 22 When lowered, this actuating arm 24 is adapted to push down the driver bit 8 via the coupling 7.

In the embodiment of the present invention configured as described above, the sequence of automatically adjusting the screws 9 attached to the components of, for example, a VTR will be explained.

After this automatic screw adjusting device is positioned upward by a moving mechanism (not shown), the driver bit 8 and guide block 13 are lowered as much as possible by operating the air cylinders 17 and 22. That is, when the air cylinder 17 is operated, the tapered hole 20 provided in the positioning plate 19 fixed to the spindle of the air cylinder 17 fits into the tapered shaft portion 15 provided at the upper end of the guide block 13, and the guide block 13 is moved. Push down. Therefore, the guide block 13 connects the driver bit 8 via the stepped portion 8b of the driver bit 8.
is lowered, so the portion below the universal joint 5 is pulled straight and held in a fixed state. Then, the stepped portion 8 of the driver bit 8
By appropriately selecting the position b, the tip of the guide block 13 is positioned below the tip of the driver bit 8. In this state, the entire device is lowered to bring the guide block 13 into contact with the screw 9. In this state, the air cylinders 17 and 22 are operated as described above, so even if there is misalignment between the driver bit 8 and the screw 9, the tapered recess 14 is located at the lower end of the guide block 13. , the lower end 8a of the driver bit 8 shown by diagonal lines becomes the screw head of the screw 9. 10 grooves 1
Matches 1. Further, when the motor 2 is rotated in this state, the lower end 8a of the driver bit 8 enters into the groove 11 of the screw 9. After that, the air cylinders 17 and 22 are activated to pull the spindles 18 and 23 upward, and the universal joint 5
Free the following parts. If universal joint 5 and below are freed in this way, even if there is misalignment between driver bit 8 and screw 9 at first, the external force in the horizontal direction due to misalignment will be applied to screw 9.
has no effect on

Furthermore, even if the screw 9 rotates and moves vertically, the amount of movement is absorbed by the ball spline 6, so no vertical force acts on the screw 9. However, the weight of the driver bit 8, the guide block 13, the coupling 7, and the rotating shaft 3c acts on the screw 9.

In the above embodiment, a ball spline is used as the spline, but the spline is not limited to this, and a normal spline may also be used.

Further, although an air cylinder is used as the cylinder, other cylinders may be used as long as the force in the vertical direction can be adjusted.

[Effects of the Invention] As explained above, in this invention, since the guide block is provided on the outside of the driver bit, misalignment between the driver bit and the screw can be absorbed by the amount of elastic deformation, and the driver bit can be attached to the screw. This has the advantage that it can be easily fitted.

In addition, the driver bit is not directly connected to the motor's rotating shaft, but a universal joint or coupling is interposed between the motor's rotating shaft and the driver bit, which prevents the driver bit from exerting external force on the screw. This has the effect of improving the accuracy of screw adjustment and improving productivity.

[Brief explanation of the drawing]

The drawing is a front view showing an embodiment of the invention. 2... Motor, 3... Rotating shaft, 5... Universal joint, 3a to 3c... Rotating shaft (rotation transmission shaft),
6... Ball spline (spline), 7... Coupling, 8... Driver bit, 9... Screw, 13
...Guide block, 17...Air cylinder, 14...
Tapered recessed portion, 15...Tapered shaft portion.

Claims (1)

[Claims] 1. An automatic screw adjustment device that automatically adjusts a screw having a groove in its head, which includes a motor and a vertical and radial screw that is axially connected to the rotating shaft of the motor and equipped with a universal joint, spline, and coupling in the middle. A rotation transmission shaft that is movable in the axial direction, a driver bit that is connected to the rotation transmission shaft in the axial direction and has a stepped portion with a lower end having a larger diameter than the upper end, and a driver bit that is fitted into the driver bit so as to be movable in the axial direction. A through hole is provided with a stepped portion that engages with the stepped portion and pushes down the driver bit when the screw is assembled and lowered, and a tapered shaft portion is provided at the upper end of the outer circumferential surface, and an inner circumferential surface is brought into contact with the head of the screw at the lower end. A guide block is provided with a tapered recess that is in contact with the screw to correct misalignment between the tip of the driver bit and the screw, and a tapered hole is provided in which the tapered shaft of the guide block is fitted so as to be removable and removable. a positioning plate;
A first cylinder supports the positioning plate so as to be movable up and down and brings the tapered recess of the guide block into contact with the head of the screw by lowering the positioning plate; An automatic screw adjustment device comprising: a second cylinder for introducing a tip of a push-down driver bit into a groove of the screw.