JPH0430421Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a shaft coupling in which two shafts are joined together by abutting each other with a taper.

BACKGROUND TECHNIQUE Conventional shaft joints are either fitted on the outside of both shafts and fixed with bolts as shown in Figure 1, or
Alternatively, a method of fitting with a taper was used, as shown in Figure 2 of Utility Model Publication No. 14-13961.

Problems to be solved by the invention The former requires a space for the joint and bolt that protrude outside the axis, while the latter, shown in Figure 2, does not protrude outward and does not require space for the joint, but when separated. required tools other than tightening, such as pulley removal. In addition, in the case of Utility Model Publication No. 14-13961, the diameter of the joint is large, the number of parts increases, and assembly work is required, resulting in high costs.

The present invention was devised in view of these problems with the conventional technology, and its purpose is to provide a shaft-coupled spindle that has a small number of parts, is extremely easy to connect and separate shafts, and is inexpensive. It is something.

Means for Solving the Problems In order to achieve the above-mentioned object, the present invention provides a shaft coupling that butts and connects shafts, in which a female taper or a male taper is formed at the connecting end of the first shaft, and a female thread is formed at the center. Drill a through hole with a
A male taper or a female taper that fits with the taper is formed at the joint end of the shaft, and a female thread is carved in the center in the same direction as the female thread of the first shaft, but with a slightly different pitch, so that the first shaft and the second shaft are connected. A keyway is cut on one side of the tapered fitting surface with the shaft, and a key is implanted on the other side, and the threaded shaft connecting the first shaft and the second shaft has a female thread on the first shaft and a thread on the second shaft. A differential thread is formed by carving two male threads with different pitches in the same direction on both ends, which engage the female threads, respectively, and a male thread that engages with the female thread of the first shaft is carved into the end. A recess is formed for the screwdriver to be inserted into the hole, and the wedging force due to the difference in screw pitch and the tensile stress on the screw shaft can be eliminated by simply turning the screw shaft in the forward or reverse direction from the center of the first shaft. The tapers of both shafts can be fitted together or separated depending on the configuration.

Function: Screw the screw shaft fully into the second shaft, match the taper, turn the screw shaft with a handle passed through the through hole, screw the screw shaft into the first shaft, and fit the taper with a pitch difference.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 3 and 4. A through hole 2 into which a turning tool such as a hexagonal handle or a driver can be inserted into the center of the first shaft 1
Drill a hole and cut a female taper 3 on the side where the shaft will be joined,
A right-handed or left-handed female thread 4 with a pitch of, for example, 1 mm is carved at the mouth of the through hole 2 that continues to the female taper 3. A keyway 5 is cut in the female taper 3 in the axial direction. The second shaft 6 connected to the first shaft 1 has a male taper 7 formed at its end, and a female thread 8 with a right or left hand thread in the same direction as the female thread 4 with a large or small pitch, for example 1.25 mm, in the center. It is set up.
A half-moon key groove 9 is cut into the male taper 7, and a half-moon key 10 is inserted therein. The threaded shaft 11, which serves as a shaft joint that connects the first shaft 1 and the second shaft 6, has a right or left male thread that engages with the female thread 4 of the first shaft 1, and a male thread 12 with the same pitch of 1 mm and the second shaft 6. A right or left male screw 13 of the same pitch of 1.25 mm is carved on each end to be screwed into the female screw 8 of the , and the end on the male screw 12 side has a hexagonal hole for a hexagonal handle or a recess for a flathead screwdriver for turning. A location 14 is formed.

To join both shafts 1 and 6 formed in this way, insert a long hexagonal handle into the through hole 2 of the first shaft 1, and apply the male thread 12 of the screw shaft 11 to the opening of the female thread 4 of the first shaft 1. , rotate screw shaft 1 with hexagonal handle
1. The rear end of the female taper 3 is screwed deeply into the female taper 3 until several threads remain. Next, the male taper 7 of the second shaft 6 is faced to the female taper 3, the key 10 and the keyway 5 are aligned in phase, and the rear end of the screw shaft 11 is connected to the female thread 8 of the second shaft 6.
press it against the mouth. Then, when the hexagonal handle of the through hole 2 is fitted into the hexagonal hole 14 of the screw shaft 11 and the screw shaft 11 is turned in the opposite direction to the direction in which it is screwed into the first shaft 1, the male thread 13 of the screw shaft 11 becomes the second It is screwed into the female thread 8 of the shaft 6. The male thread 12 of the screw shaft 11 is the first
It comes out of the female thread 4 of the shaft 1 and the threaded part is reduced. At this time, if the thread pitch of both shafts is the same, the relative positional relationship will not change, but since there is a pitch difference of 0.25 mm, the second shaft 6 is pulled together with each rotation of the screw shaft, and both shafts approach 0.25 mm, resulting in a screw thread. It is strongly joined by the wedge action. The length of each threaded portion is determined by the pitch size and pitch difference so that the number of threads that can withstand the joining force can be screwed together. In addition, the diameter of the intermediate portion between the threaded portions of the screw shaft may be made somewhat smaller, or the female thread 4 may be carved on the side opposite to the joint portion to increase the length of the intermediate portion, so that the tensile force can be applied to this portion. It is possible to cause elastic deformation and constantly generate tension. To separate the two shafts joined in this way, insert a hexagonal handle into the through hole 2 and turn the screw shaft 11 in the opposite direction to the direction used when joining, and the large force of the screw will separate the joint of the tapered part. It is something that can be done.

Effects As mentioned above, the present invention uses a differential screw for the shaft joint that joins the taper, so the pitch difference can be made arbitrarily small, and the screw's large wedge effect allows for strong tightening force. At the same time, due to the large wedge effect of the screw, the difficult separation of the tapered fitting portion can be instantaneously achieved by reversing the screw without applying an impact or using other tools. Furthermore, since the differential screw is threaded onto both shafts, loosening of the screw is reliably prevented by the tensile stress caused by elastic deformation of the screw shaft. In addition, since the component is a single screw shaft, the manufacturing cost is low, and taper joining and separation can be extremely easily performed by operating a single handle, reducing assembly and separation time. Furthermore, it can be stored compactly without requiring extra space for a shaft coupling, and can be joined and separated even within a hole. Furthermore, due to the combination of the taper and the key, there is no slippage at the joint, which has the effect of making the joint separation even more reliable.

[Brief explanation of drawings]

Figures 1 and 2 are longitudinal sectional views showing conventional joints;
FIG. 3 is a longitudinal sectional view showing the joint of the present invention, and FIG. 4 is a view showing the threaded shaft of the joint. 1...First shaft, 2...Through hole, 3...Female taper, 4, 8...Female thread, 6...Second shaft, 7...Male taper, 11...Threaded shaft, 12, 13... Male thread, 14...hexagonal hole.

Claims (1)

[Scope of utility model registration request] In a shaft coupling in which shafts are butt-joined, a through hole 2 with a female taper 3 or a male taper formed at the joint end of the first shaft 1 and a female thread 4 cut in the center is bored, and the second A male taper 7 or a female taper that fits with the taper is formed at the joint end of the shaft 6, and a female thread 8 is carved in the center in the same direction as the female thread of the first shaft but with a slightly different pitch. and second
A key groove is cut on one side of the tapered fitting surface with the shaft, and a key is implanted on the other side. Two male threads 12 and 13 with different pitches in the same direction are carved at both ends to be respectively threaded into the female threads of the two shafts to form a differential thread, and a male thread 12 is threaded into the female thread 4 of the first shaft 1. An engagement recess 14 for a screwdriver to be inserted into the through hole is formed in the end portion of the engraved hole. A shaft coupling using a differential screw, characterized in that the tapers of both shafts can be fitted together or separated by a wedge force due to the difference and a tensile stress of the screw shaft.