JPH0735226B2 - Hollow shaft with spiral groove and manufacturing method thereof - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a hollow shaft with a spiral groove used for a roll shaft for winding or rewinding paper, cloth, thin metal plates and the like, and a manufacturing method thereof.

(Prior Art) FIG. 5 shows a conventional roll shaft, in which a hollow shaft 1 with a spiral groove 2 forming a grip portion of the roll shaft 1 and tip portions of the hollow shaft 1 are fitted into both ends of the hollow shaft 1. It is composed of a solid end shaft portion 3, 3 which is joined and fixed, and one end shaft portion 3 is provided with an air supply port 4.

In the spiral groove 2 of the hollow shaft 1, as shown in FIG. 6, a rubber tube 5 for fixing a roll is spirally inserted and arranged along the groove 2. Air is supplied to the rubber tube 5 when winding paper or the like, and this air is once introduced into the hollow portion of the hollow shaft 1 through the air supply port 4 and then penetrated through the hollow shaft 1. It is supplied to the rubber tube 5 through the hole. Then, air is supplied to the rubber tube 5 to expand and expand the diameter of the tube 5 so that the tube 5 projects from the opening surface of the spiral groove 2, so that the roll is wound directly on the hollow shaft 1 or through a paper tube. Paper or the like is held integrally with the hollow shaft 1. Further, by deflating air to shrink the rubber tube 5, a gap is created between the outer peripheral surface of the hollow shaft 1 and the inner peripheral surface of the roll paper or the like, and the roll paper or the like can be extracted from the hollow shaft 1.

(Problems to be Solved by the Invention) By the way, the hollow shaft 1 with a spiral groove, which is a grip portion of the conventional roll shaft as described above, is integrally formed by casting, or is formed into a hollow cylinder having a considerably thick wall. A spiral groove is formed on the outer peripheral surface of a steel material by cutting. For this reason, in the former cast product, if the shaft diameter, shaft length or pitch or number of spiral grooves is changed during manufacturing, it is necessary to create a mold accordingly, and On the other hand, there is a problem that it is necessary to perform mechanical finishing, and therefore the cost is very high, and the hollow shaft produced by the latter machining requires a hollow cylindrical steel material of considerable thickness, etc. Since the steel pipe material of the above can not be used, the required hollow cylindrical steel material etc. must be manufactured separately, and even if a spiral groove with a U-shaped cross section can be formed, it is extremely difficult to form a dovetail groove by cutting Or there was a problem that it was impossible.

The present invention is intended to solve such problems in the conventional art.

(Means for Solving the Problems) In order to achieve the above object, in the spiral grooved hollow shaft of the present invention, the hollow shaft is made of a plastically deformable pipe material, and the spiral groove is formed along the outer peripheral surface by forming. And an outer pipe and an inner pipe integrally inserted into the outer pipe and having a strength equal to or higher than that of the outer pipe.

The dovetail groove is most preferable as the spiral groove. And, as a method of manufacturing the hollow shaft with a spiral groove, a spiral groove is formed along the outer peripheral surface of the outer pipe made of a plastically deformable pipe material by forming, and the outer pipe having the spiral groove is formed. In this method, an inner pipe made of a pipe material having strength equal to or higher than that of this pipe is inserted and both pipes are integrally fixed to each other.

(Example) FIG. 1 shows a hollow grooved hollow shaft 11 according to the present invention. The hollow shaft 11 has a U-shaped cross section along its outer peripheral surface by swaging (swaging) as a forming process. An outer pipe 13 made of a thin-walled aluminum pipe having a single spiral groove 12 provided therein, and an inner pipe 14 made of a thick-walled carbon steel pipe for machine structure integrally inserted into the outer pipe 13. It consists of a double pipe.

In manufacturing the hollow shaft 11 with a spiral groove, a swaging machine is first used to transfer the outer pipe 13 made of a required thin-walled aluminum pipe at a constant speed around its axis and at a constant speed in the axial direction. On the other hand, the swaging die compresses the outer pipe in the direction perpendicular to its axial direction to form the spiral groove 12 having a U-shaped cross section. in this case,
The pitch of the spiral groove 12 can be set arbitrarily, and the number of threads of the spiral groove 12 is not limited to one, but may be two, three, four, and so on.

Next, the outer pipe 13 provided with the spiral groove 12 as described above.
In, the inner pipe 14 made of the thick carbon steel pipe described above is inserted, and both pipes 13 and 14 are integrally fixed, but as a method of integrally fixing both pipes 13 and 14,
Shrink fitting, adhesion, or a knock pin method can be appropriately adopted. That is, in the case of shrink fitting, by inserting the inner pipe 14 into the outer pipe 13 in a state where the outer pipe 13 is heated to a high temperature and expanded and expanded, and then the outer pipe 13 is cooled and shrunk, the outer pipe 13 is It can be fixed integrally on the inner pipe 14. In the case of adhesion, both pipes may be adhered using a desired adhesive material for metal adhesion, and in the case of a knock pin, for example, the spiral groove 12 of the outer pipe 13
A plurality of knock pins may be passed through the inner pipe 14 from the bottom side to fix the two pipes 13 and 14 to each other.

Further, as described above, there is a method in which the spiral groove 12 is formed on the outer pipe 13 by swaging and then the inner pipe 14 is inserted into the outer pipe 13 to integrally fix the both pipes 13 and 14, but swaging is performed. Before performing, the inner pipe 14 having a desired outer diameter is inserted into the outer pipe 13, and during the swaging of the outer pipe 13, the outer pipe 13 is simultaneously crimped to the inner pipe 14 by its compression action, and thus both Pipe 13,14
Can also be integrally fixed.

Further, the spiral groove formed in the outer pipe 13 is preferably a dovetail groove 15 as shown in FIG. 4 rather than the groove 12 having a U-shaped cross section as shown in FIGS. This is because when the rubber tube 5 as shown in FIG. 6 is inserted into the spiral groove, the rubber tube 5 is easily detached from the groove if it is a U-shaped groove 12, and if it is detached, the fitting work is performed. It will take time and effort, but in the case of the dovetail groove 15, this groove 15
This is because if the rubber tube 5 is inserted into the, it will not come out.

Then, to form such an ant-shaped spiral groove 15,
The dovetail-shaped spiral groove 15 can be easily formed by adopting a method in which swaging is performed on the plastically deformable outer pipe, which is almost impossible by cutting as in the past.

In the above embodiments, only swaging is described as the processing method for forming the spiral groove in the outer pipe, but as another method, forming roll processing or bulge forming processing can be adopted.

Further, in the examples, the outer pipe is an aluminum pipe, and the inner pipe is a carbon steel pipe for machine structure, but the outer pipe is the carbon steel pipe, the stainless steel pipe or the like, and the inner pipe is an aluminum pipe, a FRP pipe, a carbon pipe. A pipe-making machine or the like can be used. In this case, when an aluminum pipe is used as the outer pipe, a carbon steel pipe or a stainless steel pipe is used as the inner pipe, and when a stainless steel pipe is used as the outer pipe, a stainless steel pipe, a FRP pipe, a carbon pipe or the like is used as the inner pipe. Is good.

Then, as the outer pipe, a metal pipe material such as thin-walled and plastically deformable steel pipe or aluminum pipe is used, and as the inner pipe, the strength (bending strength or shear strength) of the entire inner pipe is equal to or stronger than that of the outer pipe. A relatively thick-walled pipe material having higher strength is used. Particularly when an aluminum pipe or a FRP pipe is used as the inner pipe, it is preferable to use a pipe material having a sufficiently thicker wall thickness than the outer pipe.

(Effect of the Invention) The hollow shaft with a spiral groove of the present invention is equivalent to an outer pipe in which a spiral groove is formed along the outer peripheral surface by forming and an outer pipe integrally attached to the outer pipe. Alternatively, since it is composed of a double pipe with an inner pipe having a higher strength, it is easier to manufacture than the conventional hollow shaft having a single integrated structure, and the cost can be significantly reduced. Further, since different materials can be used for the outer pipe and the inner pipe, the weight can be reduced by combining the materials of the inner pipe and the outer pipe.

Further, by forming the spiral groove as a dovetail-shaped groove, there is no risk that the rubber tube inserted and arranged along this groove will come off from the groove, and no extra labor is required.

Then, as a method of manufacturing a hollow shaft with a spiral groove, a spiral groove is formed on an outer pipe made of a plastically deformable pipe material by a forming process along an outer peripheral surface thereof, and the outer pipe having the spiral groove is formed. Since the inner pipe is inserted and both pipes are integrally fixed to each other, the forming process of the outer pipe is easy, and the inner and outer pipes can be fixed easily by shrink fitting or adhesion. ,
Moreover, it can easily respond to changes in the pitch of the spiral groove and the construction
Therefore, the manufacturing cost can be remarkably reduced, and it is optimal for manufacturing a wide variety of hollow shafts with spiral grooves.

[Brief description of drawings]

FIG. 1 is a front view of a hollow shaft with a spiral groove showing an embodiment of the present invention, FIG. 2 is a partially enlarged sectional view of the same, FIG. 3 is a partially enlarged sectional perspective view of the same, and FIG. FIG. 5 is a sectional view of a hollow shaft having a dovetail-shaped spiral groove, FIG. 5 is an overall front view of a roll shaft showing a conventional example, and FIG. 6 is a partially enlarged sectional view of the same, showing a rubber inserted in the spiral groove. The tube is also shown. 11 …… Hollow shaft, 12 …… Spiral groove, 13 …… Outer pipe, 14 ……
Inner pipe, 15 ... Dovetail-shaped spiral groove.

Claims (3)

[Claims] 1. An outer pipe which is made of a plastically deformable pipe material and has a spiral groove formed along the outer peripheral surface by forming, and an outer pipe which is integrally attached to the outer pipe and is equivalent to the outer pipe. A hollow shaft with a spiral groove, comprising a double pipe with an inner pipe having the above strength. 2. The hollow shaft with a spiral groove according to claim 1, wherein the spiral groove is a dovetail groove. 3. An outer pipe made of a plastically deformable pipe material is provided with a spiral groove along its outer peripheral surface by a forming process, and the outer pipe provided with the spiral groove is equal to or more than this pipe. A method for producing a hollow shaft with a spiral groove, characterized in that an inner pipe made of a tubular material having strength is inserted and both pipes are integrally fixed to each other.