JPH0780102B2 - Method and device for tightening screw parts - Google Patents

Description

TECHNICAL FIELD The present invention relates to tightening of screw parts (for example, nuts and screws), and particularly to tightening of molded screw parts.

[Prior Art] As a conventional method of tightening a screw part, there is a method of rotating the screw part only in the forward rotation direction to tighten the screw part.
In this method, there is a problem that an erroneous tightening operation occurs in which the male screw body and the female screw body are engaged with each other.

As an example of solving this problem, Japanese Patent Laid-Open No. 58-120437 has been proposed. According to the method disclosed in Japanese Patent Laid-Open No. 58-120437, the screw is rotated in the normal direction at the start of tightening, reversely rotated only when there is erroneous tightening, loosened once, and then rotated in the normal direction again to tighten.

[Problems to be Solved by the Invention] However, in Japanese Patent Laid-Open No. 58-120437, since the forward rotation is always performed at the start of tightening, the chance of erroneous tightening does not decrease, and therefore the molded screw part In such a case, there is a problem that the screw part will be damaged once erroneous tightening occurs.

The present invention has been made in view of the problems of the above-described conventional example, and an object of the present invention is to provide a method and apparatus for tightening a screw component that does not cause a malfunction from the start of tightening.

[Means for Solving the Problem] In order to achieve the above object, a method for tightening a screw component according to the present invention is such that one screw component 1 is sent to a temporary fastening position, and the other screw component 1 is placed at this temporary fastening position. Temporary fastening device 4
While pressing the screw parts 1 with each other, reverse the specified amount,
After that, the screw parts 1 are rotated forward by 1 to 3/2 and temporarily held, and then the screw components 1 are temporarily held and sent to a temporary holding posture detection position, where the temporary holding posture is set to a predetermined state by the posture detecting means 5. It is characterized in that after the inspection, it is confirmed that the temporary holding posture is in a predetermined state, it is further rotated in the forward direction to be fully tightened.

Further, a tightening device for a screw component 1 for achieving the above object is a temporary tightening for rotating the screw components 1 in a pressed state and rotating the screw components 1 to 3/2 forward and then temporarily holding them. The device 4, the posture detection means 5 for inspecting whether the temporary holding posture is in a predetermined state, and the normal detection posture 5 after confirming that the temporary holding posture is in the predetermined state, normal rotation and final tightening The attitude detecting means 5 constantly pushes the slide unit cylinder 32 for lowering the detection rod 30 to hit the screw component 1 and the detection rod 30 downward. The spring 31, the dog 33 having the sensor projection hole 34 attached to the detection rod 30, and the detection rod 30 are lowered to project and receive light through the sensor projection hole 34 when hitting the screw component 1. Consists of a sensor 35 that obtains a signal It is characterized by comprising.

[Operation] While the screw part 1 is being pressed by the pressing means 2, it is reversed by the reverse rotation drive means before the screwing is started, and the screwing position detecting means 3 detects a state close to the screwing of the screw part 1 in this reversing operation process. After that, by performing normal rotation by the normal rotation drive means, it was possible to prevent erroneous tightening from the start of tightening.

In addition, the temporary fastening device 4 presses the screw components 1 to each other and reverses them by a predetermined amount, and then slightly rotates the screw components forward to temporarily hold them, and then the posture detecting means 5 makes the temporary holding posture in a predetermined state. It may be inspected whether or not it is confirmed that the temporary holding posture is in the predetermined state, and then, the final fastening device 6 may perform the forward rotation to perform the final fastening.

[Embodiment] A detailed description will be given below based on an embodiment showing the accompanying drawings of the present invention. In the present invention, the screw tightening includes three steps of the temporary tightening step of the screw component 1, the temporary holding posture detecting step of detecting the temporary holding posture of the screw component 1 temporarily held by the temporary tightening, and the final tightening step.
It is divided into steps, and the positions of these three steps are different from each other. Then, the screw component 1 is, for example, horizontally moved by a conveyor, rotationally moved by an index, or the like, the temporary fastening position, the temporary holding posture detection position for detecting the temporary holding posture of the screw component 1 temporarily held by the temporary fastening, and the final fastening position. Of 3
It moves to three different positions. That is, the first
The screw part 1 at the position shown in FIG.
b) is sent to the temporary tightening position shown in FIG. 1 (b), and the female screw body 1a which is the other screw part 1 is pressed by the temporary tightening device 4 between the screw parts 1 at this position (b). A certain amount of reverse rotation is performed, and then the screw parts are slightly rotated forward to be temporarily held, and then the screw parts 1 are temporarily held and sent to the temporary holding posture detection position shown in FIG. 1C, where The posture detecting means 5 inspects whether or not the temporary holding posture is in the predetermined state, and sends the component 1 confirmed to have the temporary holding posture to the predetermined state to the position shown in FIG. The tightening device 6 makes a normal rotation to perform final tightening.

The temporary tightening device 4 used in the present invention has a structure as shown in FIGS. That is, the front-rear operation unit 11 mounted movably in the front-rear direction with respect to the base 10.
A lower support 12 is fixed to the lower support 12, and a rotary shaft 13 is inserted into the lower support 12 so as to be rotatable and vertically movable. A chuck 19 is provided below the rotary shaft 13, and an upper portion of the rotary shaft 13 is rotatably attached to an upper support body 14. The rotary shaft 13 and the upper support 14 move integrally with each other. A motor 15 such as a pulse motor is supported on the upper support 14, and the rotation of the motor 15 is transmitted by a timing belt 26 to a pulley 16 provided on the upper end of the rotary shaft 13. An upper part of a guide shaft 17 is fixed to the upper support 14, and the guide shaft 17 is slidably fitted in the lower support 12 up and down. An air passage 18 is formed on the rotary shaft 13,
The chuck 19 is opened and closed by supplying or stopping the supply of air from 18. A substantially intermediate portion of the seesaw body 20 is rotatably supported on the base 10 by a shaft 21, and a roller 22 provided at one end of the seesaw body 20 is provided in a laterally long groove 23 provided on a side surface of the upper support body 14. A roller 24 that is fitted to the seesaw body 20 so that it can move laterally
Is rolling on the cam surface 25. Therefore, the load of the upper support 14 supporting the rotating shaft 13 is supported by the cam surface 25 via the seesaw body 20. The cam 27 is rotated by a gear 27 transmitted from a motor (not shown).
The roller 24 is rotated by moving the cam surface 25.
The height of the roller changes, and based on this, the seesaw body 20 rotates around the shaft 21 and the height of the roller 22 changes, and the upper support body
14 moves up and down in the arrow direction P, and the rotary shaft 13 slides up and down with respect to the lower support 12. The pressing means 2 is constructed by attaching both ends of a spring material such as a tension spring to the upper support body 14 and the lower support body 12, and the spring force of the pressing means 2 pushes the upper support body 14 downward. It is acting, and therefore this gives a spring force to press the screw part 1 gripped by the chuck 19. That is, in the present embodiment, the above-mentioned screw material is used for tightening the screw component 1 so as to tighten the female screw body 1a of the screw component 1.
The pressing means 2 presses the male screw body 1b with the male screw body 1b.

The screw member 1 is tightened by using the device as described above. As the screw component 1, in the accompanying drawings,
A female threaded body 1a such as a nut and a male threaded body 1b are shown. Then, with the male screw body 1b side being arranged at a predetermined position, the male screw body placed at the position a in FIG. 2 (a).
1a is gripped by the chuck 19 and moved as shown by an arrow Q in FIG. 2 (a) to be positioned above the male screw body 1b. Here, in order to perform the above operation, the front-rear moving unit 11 is moved in the lateral direction R, and when the chuck 19 comes above the position of the female screw body 1a of FIG. 2 (a), it is moved by the cam surface 25. The seesaw body 20 is rotated to move the chuck 19 to the upper support 14 and the rotary shaft 13.
Together with the cam surface 25 by gripping the female screw body 1a at the position a with the chuck 19 by supplying air.
Is moved to raise the chuck 19 holding the female screw body 1a together with the rotary shaft 13 and the upper support 14, and the front-rear moving unit 11 is moved in the opposite direction to the original position (that is, FIG. The position where the screw component 1 shown in FIG. Then, the cam surface 25 is moved next, the chuck 19 is lowered, and the female screw body 1a is pressed against the male screw body 1b by the pressing means 2 made of a spring material. In this state, when the motor 15 such as a pulse motor is reversely rotated, the rotary shaft 13 is reversely rotated via the timing belt 26,
Female screw body gripped by a chuck 19 provided at the bottom of the rotary shaft 13.
1a rotates in the reverse direction. After the female screw body 1a which is the screw component 1 is reversely rotated by a predetermined amount, it is positively rotated by 1 to 3/2 and temporarily held, and when the temporary holding is finished, the chuck 19 is lifted to return to the initial state.

By the way, in the embodiment of the present invention, the motor 15 such as the pulse motor is rotated in the forward direction by the switching means which is the motor control circuit, or is rotated in the reverse direction to rotate the rotating shaft 13 in the forward direction or in the reverse direction. Since the female screw body 1a held by the chuck 19 is rotated in the normal direction or in the reverse direction, the motor 15 that rotates in the normal or reverse direction by this switching means.
Is used as both the reverse rotation drive means for rotating the screw components 1 in the pressed state and the normal rotation drive means for driving the screw components 1 in the normal direction by detecting the screwing position.

The posture detecting means 5 has a mechanism as shown in FIG. The detection rod 30 is constantly pressed downward by the spring 31, and when the slide unit cylinder 32 descends and hits the female screw body 1b, the state of the chain double-dashed line in FIG. 4) is attached to this detection rod 30. Push down one dog 33,
The sensor 35 projects and receives light through the sensor light projecting hole 34 provided in 33 to obtain a signal (OK signal). If the heights are different, the sensor 35 does not project or receive light and determines that the posture is not normal.

The final tightening device 6 has a structure as shown in FIG.
The final tightening device 6 is the same as the temporary tightening device 4 except that a mechanism for moving back and forth and a chuck 19 are removed. And
A socket ring 36 for final tightening is provided in the lower part of the rotary shaft 13 instead of the chuck 19, and the socket ring for final tightening is provided.
36 has a hexagonal shape corresponding to the female screw body 1a made of a nut in the embodiment of the accompanying drawings. Then, when the screw member 1 temporarily held in a normal posture comes under the final tightening device 6 at the position (d) in FIG. 1, the rotary shaft 13 is lowered, and the final tightening socket ring 36 is lowered. In this case, the socket ring 36 for final tightening fits into the female screw body 1a by rotating at low speed. After that, by further rotating the final tightening socket ring 36 at high speed, the female screw body 1a is tightened to the male screw body 1b to a predetermined position, and when the final tightening is finished, the rotary shaft 13 is raised to return to the initial position. .

EFFECTS OF THE INVENTION The invention according to claim 1 of the present invention is one in which one screw component is sent to a temporary fastening position and the other screw component is pressed between the screw components by the temporary fastening device at this temporary fastening position. A certain amount of reverse rotation, then forward rotation of 1 to 3/2 to temporarily hold it, and then send the screw components to the temporary holding posture detection position while temporarily holding them together, where the temporary posture is detected by the posture detecting means. After checking whether it is in the predetermined state and confirming that the temporary holding posture is in the predetermined state, it is further rotated in the forward direction to perform final tightening.Therefore, when tightening the screw parts together, press the screw parts together. While reversing by a predetermined amount, then 1 to 3 /
(2) Rotate forward and temporarily hold, and in this temporary holding state, you can check whether the screw components are in a normal posture or an abnormal posture, and rotate forward 1 to 3/2 to temporarily hold. If the temporary holding posture is not in the normal state, the final tightening is not performed, and the final tightening can be done only when the normal holding posture is confirmed.
It is possible to prevent erroneous tightening and prevent damage such as scratches on the threaded portion.

In the invention according to claim 2 of the present invention, the screw parts are reversed in a pressed state, and after the screw parts are reversed, the screw parts are 1 to 3/2.
A temporary fastening device for normal rotation and temporary holding, and a posture detecting means for inspecting whether the temporary holding posture is in a predetermined state,
And a final tightening device for performing normal rotation and final tightening after it is confirmed by the attitude detecting means that the temporary holding attitude is in a predetermined state, and the attitude detecting means lowers the detection rod to form a screw component. When the slide unit cylinder to hit, the spring that constantly pushes the detection rod downward, the dog that has the sensor light projecting hole attached to the detection rod, and the detection rod that is lowered and hits a screw part Since it is configured with a sensor that emits and receives light through the sensor light emitting hole to obtain a signal, it is possible to confirm whether the temporary holding posture is normal with a simple configuration and then perform the final tightening with the final tightening device. It is possible to provide a device that can do this.

[Brief description of drawings]

FIG. 1 is a process drawing of an embodiment of the present invention, and FIGS. 2 (a) and 2 (b).
Is a front sectional view and a side sectional view of the temporary tightening device used in the same as above, FIG. 3 is a schematic sectional view of the same as above, and FIGS. And a schematic side view, and FIGS. 5 (a) and 5 (b) are a schematic front sectional view and a schematic side sectional view of the final tightening device used in the above,
Reference numeral 1 is a screw part, 2 is a pressing means, 4 is a temporary fastening device, 5 is a posture detecting means, and 6 is a final fastening device.

Claims (2)

[Claims] 1. One screw part is sent to a temporary tightening position, and at this temporary tightening position, the other screw part is reversed by a predetermined amount while pressing the screw parts by a temporary tightening device, and then 1 to 3/2. The screw parts are rotated forward and temporarily held, and then the screw parts are temporarily held and sent to the temporary holding posture detection position. Here, the posture detecting means inspects whether or not the temporary holding posture is in a predetermined state. A method for tightening a screw component, which further comprises rotating in a normal direction and finally tightening after it is confirmed that the temporary holding posture is in a predetermined state. 2. A temporary tightening device for reversely rotating the screw parts in a pressed state, and for temporarily holding the screw parts by normally rotating 1 to 3/2 after the reverse rotation, and whether or not the temporary holding posture is in a predetermined state. The attitude detecting means for inspecting whether or not, and the final tightening device for performing normal rotation and final tightening after the temporary holding attitude is confirmed to be in a predetermined state by the attitude detecting means, The slide unit cylinder for lowering and lowering the operating rod against the screw parts, the spring that constantly pushes the detecting rod downward, the dog with the sensor projection hole attached to the detecting rod, and the detecting rod. A device for tightening a screw part, which comprises a sensor for projecting and receiving light through a sensor light projecting hole to obtain a signal when the screw part is lowered and hits the screw part.