JPH0128986Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> This invention provides high accuracy for shaft assembly, such as when fixing the shaft to the rotor of an electric motor, fixing the shaft to the flywheel of a capstan, or fixing the shaft to a bearing. This invention relates to a cooling device for shafts in the cold fitting technology used in required applications.

<Prior Art> As a means of fitting the shaft into the shaft insertion hole, there are fitting techniques that utilize the expansion and contraction of members due to temperature differences, such as press-fitting at room temperature, shrink-fitting, and cold-fitting. In press-fitting at room temperature, the shaft is forcibly press-fitted, which causes deformation and strain in the component, and has the disadvantage of low fitting accuracy.Shrink-fitting heats the joining component, which causes deterioration of the structure of the component. This has the drawback of causing deformation strain in the member. Both of the above two methods have the problem of high equipment costs. Therefore, in recent years, cold fitting, in which the coupling members are cooled and fitted, has been used in products that require high assembly accuracy.

As a shaft cooling device used for cold fitting,
Conventionally, the shaft is housed in a cooling chamber inside an insulated case, and a cryogen such as liquid nitrogen or liquid carbon dioxide is injected into the cooling chamber, and the shaft is cooled using the latent heat of vaporization.

《Problems that the invention aims to solve》 However, since conventional cooling equipment uses so-called batch processing, it is not possible to perform the fitting operation following the cooling process continuously, and the work efficiency as a cold fitting process is reduced. In addition to the problem that the
There is also the problem that the temperature within the cooling device varies due to the flow of the ejected gas, and the degree of cooling varies depending on the position of the shaft within the cooling device.

<Means for Solving the Problems> The present invention allows all shafts to be cooled under the same conditions by continuously cooling the shafts used for cold fitting. To provide a cooling device that can perform the subsequent fitting work continuously and improve the work efficiency of the cold fitting process as a whole, in order to do so, a liquid nitrogen reservoir is formed inside the heat insulating case, and a constant temperature is A rotating drum made up of a pair of side plates connected by shaft supports placed at intervals is placed in a heat insulating case, and this rotating drum is supported in a state where it can rotate around a horizontal axis, and the horizontal axis of the rotating drum is The lower part of the drum is inserted into the liquid nitrogen reservoir, and the rotary drum is rotated in steps at a constant pitch by an intermittent drive device.A shaft insertion guide and a shaft are installed on the outside of one side plate of the rotary drum. and the extrusion device are arranged side by side with the shaft extrusion device located on the upper side in the drum rotation direction,
A shaft removal guide is placed on the outside of the other side plate of the rotating drum, facing the shaft extrusion device, and a liquid level detector for detecting the liquid level position in the liquid nitrogen reservoir is placed in the heat insulating case. The present invention is characterized in that the amount of liquid nitrogen fed into the heat insulating case is controlled based on the liquid level detected by the tool.

《Operation》 A liquid nitrogen reservoir is formed inside the heat insulating case, and a rotating drum made up of a pair of side plates connected by shaft supports placed at regular intervals on the outer periphery is rotated in steps at regular pitches. Since the part of the rotating drum located below the horizontal axis is plunged into the liquid nitrogen reservoir, the shafts can be cooled by being immersed in liquid nitrogen for a certain period of time, and the degree of cooling of each shaft can be adjusted. can be made uniform. Further, a shaft insertion guide and a shaft extrusion device are arranged side by side on the outside of one side plate of the rotating drum, with the shaft extrusion device positioned on the upper side in the direction of rotation of the drum, and a shaft ejection guide is placed on the outside of the other side plate of the rotary drum. Since the guide tool is disposed facing the shaft extrusion device, the shaft can be continuously taken out at regular intervals and the next step, the fitting step, can be performed continuously.

<<Embodiment>> The drawings show an embodiment of the present invention, in which FIG. 1 is a partially cutaway perspective view of a capstan cooling device, and FIG. 2 is a partially cutaway plan view of a delivery portion of a shaft.

In this capstan cooling device, the lower half of an insulating case 1 is formed into a liquid nitrogen reservoir 2, and a rotating drum 3 is placed inside the insulating case 1, with approximately 1/3 of its diameter protruding into the reservoir 2. It is arranged so that it can rotate around a horizontal axis.

As shown in FIG. 2, this rotating drum 3 is formed by mounting shaft supports 6 made of stainless steel mesh tubes at regular intervals between the outer peripheral edges of a pair of side plates 4 and 5. .

A shaft insertion guide 7 is installed on the outside of one side plate 4 of the rotating drum 3 in the upper space inside the heat insulating case 1.
and a shaft extrusion device 8 are arranged side by side in the rotational direction of the drum with the shaft extrusion device 8 positioned on the upper side in the rotational direction of the drum, and a shaft extraction guide is provided on the outside of the other side plate 5 of the rotating drum 3. 9 is arranged opposite to the shaft extrusion device 8.

The shaft insertion guide 7 is used for untreated shaft S.
introduction guide path 10 for aligning and introducing in a horizontal position
and a shaft sending device 11 that sends out the introduced unprocessed shaft S to the rotating drum 3 side. There is.

The shaft extrusion device 8 is a push rod 13 of the shaft S.
This push rod 13 and the cylinder tool 1 for moving in and out
It consists of 4.

The shaft retrieval guide 9 is formed of an inverted L-shaped duct protruding from the side wall 15 of the heat insulating case 1, and the bottom wall 16 of the horizontal passage portion is formed with a downward slope, so that the shaft retrieval guide 9 can be removed from the rotating drum 3 in a horizontal position. The treated shaft S that has been taken out is changed to a vertical position and then taken out. The vaporized low-temperature nitrogen gas is allowed to flow through the shaft removal guide 9.

A liquid level detector 17 for detecting the liquid level position in the liquid reservoir 2 is disposed in the heat insulating case 1. Based on the liquid level detection by the liquid level detector 17, an intervening liquid nitrogen supply system 18 is installed. By controlling the opening degree of the solenoid valve 19,
It is formed so that the amount of liquid nitrogen in the liquid reservoir 2 is always constant.

The rotating drum 3 is controlled by an intermittent drive device 20 so as to rotate at regular pitches.

Reference numeral 21 in the figure is a gas-liquid separator disposed in the liquid nitrogen supply system 18, and is designed to allow only liquid nitrogen to be fed into the heat insulating case 1. Also, code 2
2 is a vaporized nitrogen discharge path, 23 is a liquid nitrogen tank, 24
is a shaft pull-out prevention plate placed on the outside of both side plates 4 and 5 of the rotating drum 3.

《Effects of the invention》 As mentioned above, the present invention forms a liquid nitrogen reservoir in a heat insulating case and connects a pair of side plates with shaft supports arranged at regular intervals on the outer periphery. The drum is configured to rotate in steps at a constant pitch, and the portion of the rotating drum located below the horizontal axis is plunged into the liquid nitrogen reservoir, so that the shaft can be immersed in liquid nitrogen for a certain period of time. The cooling degree of each shaft can be made uniform.

Further, a shaft insertion guide and a shaft push-out device are arranged side by side on the outside of one side plate of the rotating drum, with the shaft push-out device positioned on the upper side in the shaft rotation direction, and a shaft ejection guide is arranged on the outside of the other side plate of the rotary drum. The tool is arranged to face the shaft extrusion device, and the cooled shaft is pushed out from the shaft support to the shaft ejection guide by the shaft extrusion device on the upstream side of the shaft insertion guide. is taken out continuously at regular intervals,
The next process, the fitting process, can be performed continuously, and the efficiency of the cold fitting process can be improved.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a partially cutaway perspective view, and FIG. 2 is a partially cutaway plan view of a shaft delivery section. 1...Insulation case, 2...Liquid nitrogen reservoir, 3
... Rotating drum, 4, 5 ... 3 side plates, 6 ... Shaft support, 7 ... Shaft insertion guide, 8 ...
... Shaft extrusion device, 9 ... Shaft take-out guide tool, 17 ... Liquid level detector, 20 ... Intermittent drive device, S ... Shaft.

Claims (1)

[Scope of utility model registration request] A liquid nitrogen reservoir 2 is formed inside the heat insulating case 1, and a rotating drum 3 formed by connecting a pair of side plates 4 and 5 with shaft supports 6 arranged at regular intervals on the outer periphery is installed inside the heat insulating case 1. The rotary drum 3 is supported in a rotatable state around a horizontal axis, and the portion of the rotary drum 3 located below the horizontal axis is plunged into the liquid nitrogen reservoir 2, and the rotary drum 3 is intermittently rotated. A drive device 20 is configured to rotate the shaft in steps at a constant pitch, and a shaft insertion guide 7 and a shaft extrusion device 8 are installed on the outside of one side plate 4 of the rotary drum 3, with the shaft extrusion device 8 on the upper side in the direction of rotation of the drum. The shaft extraction guide 9 is arranged on the outside of the other side plate 5 of the rotary drum 3 facing the shaft extrusion device 8, and the A liquid level detector 17 for detecting the liquid level position is arranged in the heat insulating case 1, and the amount of liquid nitrogen supplied into the heat insulating case 1 is controlled based on the liquid level detected by the liquid level detector 17. Shaft cooling device for cold fitting.