JP7430361B1 - Device for screwing nuts onto bolts and method for screwing nuts onto bolts using the same - Google Patents

Abstract

[Problem] To provide a screwing device that can quickly screw together bolts and nuts that comply with various standards with a simple operation by an operator to form a pair, and that is easy to transport and move and is inexpensive, and a bolt using the same. Provides a nut screwing method. [Solution] A nut screwing device for a bolt includes a cylindrical nut holder 3 that is removably attached to a bearing member 2 connected to an output shaft 11 of a motor 1 and rotates about a vertical axis, and the nut holder 3. 3 has a bottomed cylindrical nut storage space 4 that opens vertically upward and has an inner diameter that allows a predetermined nut 5 to fit loosely therein, and is formed in the center of the upper surface of the nut holder 3. The nut holder 3 is inserted and held with the upper surface thereof exposed through an installation opening 60 formed with an opening diameter that allows the nut holder 3 to fit loosely into the table 6 of the nut holder 3. Furthermore, a groove 41 may be formed at one location on the inner peripheral surface of the nut storage space 4, extending vertically downward from the upper end edge to the inner bottom surface. [Selection diagram] Figure 1

Description

The present invention relates to a screwing device for screwing a nut onto a bolt that complies with various standards to form a pair, and a method for screwing a nut onto a bolt using the same.

Traditionally, devices for threading nuts onto bolts have been carried out by rotating either the bolt or the nut, and in the case of large-volume processing, it has been carried out using fully automatic large-scale equipment, resulting in efficient processing. . On the other hand, in the case of multi-standard, small-volume processing, the current situation is that it is carried out manually by workers. Performing this with a large mechanical device would not only make the setup complicated, resulting in poor workability, but also would be extremely uneconomical considering the cost of the device.

In addition, even in small quantities, manually screwing together a wide variety of bolts and nuts forces workers to tense up for long periods of time, resulting in variations in the positions at which nuts are attached to bolts, which reduces work efficiency. Not only was it bad, but it lacked stability in handling.

As a solution to this problem, a mechanical device that uses a sensor or the like to detect and automate the screwing position of a nut onto a bolt is disclosed in, for example, Patent Document 1 and Patent Document 2.

Utility Model Publication No. 06-074238 JP 2019-123036 Publication

However, since the disclosed invention is an automated machine with a large number of component parts, there is a problem that maintenance becomes complicated. Additionally, many of the devices are large and fixedly installed, making them difficult to transport and move. Naturally, such devices are expensive and cannot be easily operated or transported.

Therefore, the present invention has been made in view of the above-mentioned problems, and its purpose is to quickly screw together bolts and nuts that comply with various standards with a simple operation by an operator to integrate them into one pair. An object of the present invention is to provide a screwing device that can be easily transported, is inexpensive, and a method of screwing a nut onto a bolt using the same.

In order to solve the above-mentioned problem, the bolt-nut screwing device according to the present application is configured as follows.

That is, a cylindrical nut holder is detachably attached to a bearing member connected to an output shaft of a motor and rotates about a vertical axis, and a predetermined nut is loosely fitted in the center of the upper surface of the nut holder. A cylindrical nut storage space with a bottom is formed, which opens vertically upward with an inner diameter and has an inner bottom surface that can come into contact with the lower surface of the nut , and the nut holder is loosely fitted onto a horizontal plate-shaped table. The nut holder is inserted and held through an installation opening formed with a suitable opening diameter with the upper surface exposed, and the nut stored in the nut storage space is held by contact friction between the nut lower surface and the inner bottom surface. Attachment is accomplished by pressing the tip of the bolt against the threaded portion of the rotated nut and screwing it into the vicinity of the tip of the bolt.

Further, a groove portion may be formed at one location on the inner circumferential surface of the nut storage space, extending vertically downward from the upper edge portion to the inner bottom surface portion. As a result, when the bolt is plated or painted, the outer corner of the nut comes into contact with the edge of the groove, generating rotational force, and this, combined with the rotational force due to contact friction, creates a screwing force for the nut. can be increased.

Furthermore, the nut screwing device for the bolt has a nut holder that has a bottomed cylindrical nut storage space with a vertically upward opening and a bottomed cylindrical nut storage space with an inner diameter that allows a nut of a predetermined standard to loosely fit therein. A nut of a predetermined standard is stored in the rotating nut storage space, and the shaft is rotated by friction with the bottom of the nut storage space. The method used is to bring the tip of the bolt into contact with the threading opening of the rotating nut, and then screw the nut into the vicinity of the tip of the bolt.

The above configuration provides the following effects.

By replacing nut holders that comply with multiple standards, it is possible to quickly respond to high-mix, low-volume production. By rotating the nut by contact friction with the inner bottom surface of the nut storage space, it is possible to shorten the time required to attach the nut to the bolt and improve work efficiency.

FIG. 2 is a plan view showing the overall configuration of the present embodiment, partially in longitudinal section. FIG. 3 is a perspective view showing the correspondence of main parts of the present embodiment. It is a schematic perspective view which showed each process of screwing the nut into the bolt in this example of embodiment. It is a schematic perspective view which showed each process of screwing the nut into the bolt in this example of embodiment. It is a schematic perspective view which showed each process of screwing the nut into the bolt in this example of embodiment. It is a schematic perspective view which showed each process of screwing the nut into the bolt in this example of embodiment. It is a schematic perspective view which showed each process of screwing the nut into the bolt in this example of embodiment. It is a schematic perspective view which showed each process of screwing the nut into the bolt in this example of embodiment.

An example of a form for carrying out the present invention (hereinafter referred to as "this example of embodiment") will be described in detail with reference to the drawings.

1 is a motor as a drive source, and is disposed on a base 10 disposed at a predetermined position of a housing (not shown), with the rotating shaft of an output shaft 11 of the motor 1 facing vertically upward. A bearing member 2 is attached to the output shaft 11. This bearing member 2 is removably connected to a nut holder 3, which will be described later, to transmit shaft rotational force.

In this embodiment, the bearing member 2 is attached directly to the output shaft 11 of the motor 1 as shown in the figure, but the bearing member 2 is not limited to this, and although not shown in the figure, a gear or a A structure may also be adopted in which the bearing member 2 is connected with a belt or the like so that the axis of the bearing member 2 is directed vertically upward.

The bearing member 2 supports the rotation of a nut holder 3 having a cylindrical appearance. In this structure, a cylindrical fitting projection 30 is integrally formed that projects vertically downward from the center of the outer bottom of the nut holder 3. The fitting convex portion 30 is formed to fit into a cylindrical fitting recess 20 that opens upward from the center of the bearing member 2 . This fitting specification is such that a part of the outer peripheral surface of the fitting protrusion 30 is cut out along the axis to form a D-cut surface 31, and the fitting recess 20 is fitted with the D-cut surface 31. A protruding surface 21 is formed on the surface. With this structure, it is possible to freely attach and detach the bearing member 2 in the vertical direction, and only the axial rotational force is transmitted due to the contact between the D-cut surface 31 and the protruding surface 21. Note that this fitting structure that transmits only the rotational force is a general known technique, and may be a key connection structure, for example.

At the center of the upper surface of the nut holder 3, there is a vertically downward depth approximately equal to the height of the nut 5 (for example, approximately 25 mm in the case of M20), and a groove that fits loosely (with a slight gap) around the outer diameter of the nut 5. A bottomed cylindrical nut storage space 4 is formed with an inner diameter (for example, about 35 mm in the case of M20).

Further, in the inner circumferential surface 40 of the nut storage space 4, a groove 41 that continues from the opening edge to the inner bottom surface 42 is formed vertically downward. Although the formation of this groove 41 is not essential, depending on the product specifications of the bolt 7, the thread groove may be plated or painted, which helps increase the screwing force of the nut 5.

Further, although a part or all of the inner bottom surface 42 of the nut storage space 4 is formed in a flat shape perpendicular to the vertical rotation axis, the inner peripheral surface 42 of the inner bottom surface 42 is not limited to this. A donut-shaped flat portion (which becomes a contact surface with the nut) may be formed in the vicinity of .

The nut holder 3 is also inserted and held in a horizontal plate-like table 6, which will be described later, through an installation opening 60 formed with an opening diameter that allows loose fitting, with the upper surface of the nut holder 3 exposed. In this embodiment, it is set to be substantially flush with the plate surface of the table 6.

With this configuration, since the table 6 is arranged, the nut holder 3 can be quickly inserted and installed into the installation opening 60 (see FIG. 3), and furthermore, the top surface of the nut holder 3 and the table 6 are approximately flush with each other. Therefore, the nut 5 can be housed and held in the nut holder 3 only by a sliding operation (see FIG. 4), and work efficiency can be improved.
[Work procedure]
Next, the working procedure of the nut screwing device for the bolt having the above structure will be explained.

First, the motor 1 is installed by attaching the nut holder 3 having the nut storage space 4 suitable for the nut 5 to be screwed onto the target bolt 7 through the installation opening 60 made in the table 6 with the fitting convex part 30 facing downward. Fitting recess 20 of bearing member 2

(See Figure 3). At this time, as described above, by bringing the D-cut surface 31 formed on the fitting convex portion 30 into contact with the protruding surface 21, it is possible to transmit the axial rotational force while enabling vertically upward attachment and detachment.

Next, while driving the motor 1 and rotating the nut holder 3, the target standard nut 5 is stored in the nut storage space 4 by sliding it on the table 6 with the screw opening 50 facing vertically upward ( (See Figure 4). This storage causes the lower surface of the nut 5 to come into contact with the inner bottom surface portion 40 of the nut storage space 4, and the nut 5 rotates around its axis due to the contact friction (see FIG. 5).

By bringing the tip of a predetermined bolt 7 close to the threaded opening 50 of the nut 5 and pressing it into contact (contact while applying pressure) while maintaining this rotation, the nut 5 automatically connects with the bolt 7. They are screwed together, move upward, and separate from the inner bottom surface portion 40, so that contact friction disappears and the rotation ends (see FIG. 6).

The bolt 7 gripped at this point is held with the nut 5 screwed into the vicinity of the tip (see FIG. 7), which is convenient for handling the bolt and nut during work (see FIG. 8).

In addition, some bolts 7 have their thread grooves plated or painted, and for bolts 7 with such specifications, the lower surface of the nut 5 and the inner bottom surface 40 of the nut storage space 4 are coated. Since the threading force to the nut 5 is weak only by the contact friction force, sufficient threading may not be possible. In consideration of this, a groove 41 is formed in the inner circumferential surface 40 of the nut storage space 4 so as to extend vertically downward from the upper edge of the opening to the bottom.

By forming such a groove portion 41, the hexagonal portion on the outer peripheral side of the nut 5 comes into contact with the edge of the groove portion 41 while the nut 5 is rotating, thereby making it possible to further apply rotational force. This allows the rotational torque of the nut 5 to be increased.

As described above, by preparing various nut holders 3 having nut storage spaces 4 corresponding to nuts 5 of various standards and replacing them as appropriate, nuts 5 and bolts 7 of various standards can be used. can be quickly combined. This makes it possible to significantly improve work efficiency compared to conventional manual work.

1 Motor 10 Base 11 Output shaft 2 Bearing member 20 Fitting recess 21 Projecting surface 3 Nut holder 30 Fitting convex portion 31 D-cut surface 4 Nut storage space 40 Inner peripheral surface 41 Groove 42 Inner bottom surface 5 Nut 50 Screwing Part 6 Table 60 Installation port 7 Bolt

Claims (3)

a cylindrical nut holder that is removably attached to a bearing member connected to the output shaft of the motor and rotates about a vertical axis;
The nut holder has a bottomed cylindrical nut storage space in the center of the upper surface thereof, which opens vertically upward and has an inner diameter that allows a predetermined nut to fit loosely thereinto, and an inner bottom surface that can come into contact with the lower surface of the nut. is formed,
The nut holder is inserted and held through an installation opening formed with an opening diameter that allows it to fit loosely into a horizontal plate-like table, with the upper surface of the nut holder exposed .
The nut stored in the nut storage space is screwed near the tip of the bolt by pressing the tip of the bolt against the threaded portion of the nut rotated by contact friction between the lower surface of the nut and the inner bottom surface. A device for threading a nut onto a bolt, characterized by: 2. The nut screwing device for a bolt according to claim 1, wherein a continuous groove is formed vertically downward from the upper end edge to the inner bottom surface at one location on the inner circumferential surface of the nut storage space. . It uses a nut screwing device to a bolt ,
A nut holder is equipped with a bottomed cylindrical nut storage space with an opening vertically upward and has an inner diameter that allows a nut of a predetermined standard to fit loosely therein.
A nut of a predetermined standard is stored and held in the shaft-rotating nut storage space, and the shaft is rotated by contact friction between the lower surface of the nut and the inner bottom surface of the nut storage space,
Next, a nut to a bolt is attached by pressing the tip of the bolt against the threaded part of the rotating nut while stored and held, and screwing the nut into the vicinity of the tip of the bolt. Screwing method.

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