JPH0861376A - Bearing structure for demountable type shaft - Google Patents

Abstract

PURPOSE: To enable the mounting/demounting of a shaft easily and speedily only by raising and lowering the shaft by installing the shaft having a bearing bush in a fitted state, on a bearing frame from the upper part, and fitting the bearing bush from outside on the bearing frame. CONSTITUTION: A U-shaped groove 7 suitable for receiving a shaft 4 from the upper part is formed on a bearing frame 6, so as to be slightly wider than the diameter of the shaft 4. A receiving part 9 suitable for the fitting of a bearing bush 8 having a collar from outside is formed so as to be the larger diameter than the width of the groove 7. While, at the part close to both the ends of the shaft 4, a bearing bush 8 is fitted in the direction where the collar is positioned outside. These bearing bushes 8 are fitted from outside at the above-described receiving part 9, A collar 10 is fixed at the part close to the end part separated properly from the bearing bush 8. Inside both the collars 10, an elastic body 11 is interposed between the bearing bushs 8, and the bearing bush 8 is pressed always inward. Accordingly, the shaft can be mounted and demounted in a short time, with the simple structure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing structure of a detachable shaft in which the shaft can be easily attached and detached. For example, liquid solder is jetted upward while stirring, Like a stirring shaft in a solder wave type soldering device that contacts the uneven surface of the solder with the lower surface of the moving printed circuit board, it is required to replace it in a short time when the line production is interrupted. The present invention relates to a bearing structure of a detachable shaft such as a rotary shaft.

[0002]

2. Description of the Related Art As a conventional bearing mounting structure, a bearing bush is detachably mounted on a bearing body by a mounting screw so that the bearing bush is fixed to the bearing body by press-fitting or is convenient for replacement when worn. It is common to fix the bearing bush to the bearing body by using a snap ring or special metal fittings. Even when the shaft itself is attached and detached, it is usually necessary to attach and detach the bearing bush.

[0003]

Since it is natural that the bearing bush is detached when the shaft itself is detached, if the bearing bush is fixed to the bearing body as in the conventional mounting structure, the bearing It is extremely difficult to attach and detach the bush,
In addition, if it is detachably attached with the mounting screw,
It is possible to attach and detach, but not only the operation for attaching and detaching the mounting screw is complicated, but also a tool such as a screwdriver or spanner is required, and if the mounting structure uses special metal fittings, the tool dedicated to the metal fittings However, desorption is extremely inefficient in both cases.

Therefore, an object of the present invention is to provide a bearing structure which allows a shaft to be attached / detached in a short time under a so-called one-touch operation based on a simple structure. Another object is to use a solder wave. It is an object of the present invention to provide a bearing structure suitable for a shaft for jet solder agitation applied to a device for soldering an electronic component to a printed circuit board by a mold soldering method.

[0005]

In order to achieve the above-mentioned object, the present invention provides a pair of bearing frames with bearing bushes with flanges so as to be fitted from the outside, and the bearing frames are provided with a shaft from above. A U-shaped groove suitable for receiving is formed, and a collar that is fixed to the outside of both bearing bushes is fixed to the shaft that penetrates both bearing bushes, and an elastic body is interposed between the collar and the bearing bush. Therefore, when attaching and detaching, under the condition that both bearing bushes are expanded outward from the outer surface of the bearing frame against the elasticity of the elastic body, the shaft is inserted into the bearing bush from the U-shaped groove in the bearing frame. At the same time, the bearing bush is disengaged upward or dropped from above into the U-shaped groove, and then the bearing bush is fitted to the bearing frame by restoring the elastic body. A play prevention means is provided between the bearing frame and the bearing bush.

[0006]

[Function] While both bearing bushes are spread outward from the outer surface of the bearing frame against the elastic body, the elastic body is restored after descending from above into the U-shaped groove of the bearing frame. By doing so, the bearing bush is pressed by the elastic body and fits into the bearing frame, and the pressed state of the elastic body keeps the fitting state stable at all times, and the free play provided between the bearing frame and the bearing bush. The preventive means acts to prevent the bearing bush from freely rotating around.

The shaft can be attached to and detached from the bearing frame by expanding both bearing bushes to both outsides, and the shaft can rotate and / or move linearly in the mounted state.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG.
The embodiment shown in FIG. 3 will be described in detail. As a soldering apparatus to which the present invention is applied, generally, a nozzle former 3 that holds an appropriate amount of molten solder in a solder tank 1 that is open upward and that has an upward jet port 2 that extends in the left-right direction is fixed. A jet generator (not shown) is provided below the inside of the nozzle former 3 so that the liquid solder jetted upward from the jet port 2 is brought into contact with the lower surface of the printed circuit board P moving in the front-rear direction. In addition, a stirring shaft 4 having a concavo-convex portion is provided inside the nozzle former 3 near the jet port 2 at the base of the horizontal axis, and the shaft 4 is swung in the axial direction while rotating. As a result, irregularities of the solder liquid surface are irregularly and finely changed under the condition that the jet solder jetted upward from the jet nozzle 2 is disturbed, and the convex portions of the jet solder are evenly distributed on the lower surface of the moving printed circuit board P. To adopt was to make touch soldering apparatus.

The present invention relates to the shaft 4 in the soldering device.
Is suitable as a bearing structure of the soldering apparatus. Solder oxides and foreign matters are likely to adhere to the solder contact portion of the shaft 4 in such a soldering device during use, and the agitation function deteriorates due to the adhesion of the solder oxides and the foreign matter, thereby soldering. The quality of the
Although it is necessary to remove the shaft 4 and clean it frequently, since the shaft 4 is detached by stopping the soldering device, a bearing structure capable of easily detaching the shaft 4 is desired.

For example, as shown in FIGS. 1 and 2, the solder bath 1
The bearing frames 6 and 6 are attached to the left and right side walls 5 and 5, and each bearing frame 6 is provided with a U-shaped groove 7 adapted to receive the portions near both ends of the shaft 4 from above the diameter of the shaft 4. And a receiving portion 9 adapted to fit the flanged bearing bush 8 from the outer side is formed to have a diameter larger than the width of the groove 7, and, on the other hand, near the both ends of the shaft 4, The bearing bushes 8 and 8 are fitted in the direction in which the flanges are located on the outside so that the bearing bushes 8 and 8 are fitted to the receiving portions 9 from outside, respectively. Collars 10 and 10 are fixed near the ends separated from each other, and elastic bodies 11 and 11 such as coil springs are provided inside the collars 10 and 10 between the collars 10 and 10 and the bearing bushes 8 and 8 respectively. The bearing bushes 8 are always kept in a tendency to be pressed inward.

It is appropriate that the flange portion of the bearing bush 8 is provided with an inward projection as a play prevention means 12 that engages with the U-shaped groove 7 in the bearing frame 6, or in the bearing frame 6. The fitting shape of the receiving portion 9 and the bearing bush 8 may be formed in a shape different from the cylindrical shape, or may be tapered, and the fitting surface itself may be used as the play prevention means.

When the shaft 4 is to be removed for cleaning or replacement, the bearing bushes 8 are slid outward against the elastic body 11 to remove the shaft 4 for cleaning or replacement. After detaching from the portion 9, it may be taken out upward, and in order to mount the shaft 4, both bearing bushes 8 and 8 are slid outward against the elastic body 11 so that the inner end surface of the bearing bush 8 is removed. After the shaft 4 is inserted into the U-shaped grooves 7 and 7 of the bearing frames 6 and 6 from above under the condition that the bearing frame 6 is expanded outwardly from the outer end face portion, the bearing bushes 8 and 8 are elasticized. Body 1
It suffices for the bearing bush 8 to be fitted in the receiving portion 9 while being pressed inward by 1, and because the outer diameter of the bearing bush 8, that is, the diameter of the receiving portion 9 is larger than the width of the groove 7, the bearing bush 8 is allowed to move upward. There is no.

In order to rotate and linearly move the shaft 4, for example, from the motor 13 to the belt transmission mechanism 14.
The drive shaft 15 which is rotated through
5 and the base of the shaft 4 are connected by a detachable shaft joint 16, and the drive shaft 15 can be moved back and forth in the axial direction from a motor 17 via a swing mechanism 18 such as a cam mechanism. .

[0014]

As described above, the present invention has the following effects a. The shaft 4 is mounted on the bearing frames 6 and 6 from above with the bearing bushes 8 and 8 fitted, and
The shaft 4 is fitted to the bearing frame 6 from the outside, so that the shaft 4 can be easily and quickly attached and detached by sliding the bearing bush 8 and moving the shaft 4 up and down. b. Collars 10, 10 are fixed to a portion of the shaft 4 which is appropriately separated from the bearing bush 8 and near the end portion.
10 and the bearing bushes 8, 8 between the elastic bodies 11, 1
Since the bearing bushes 8 and 8 are always kept in a tendency to be pressed inward by the interposition of 1, the bearing bush 8 can not only be stably fitted to the bearing frame 6, but also the detaching operation can be performed. Is extremely easy and there is no need for special tools for the detaching operation.

C. By providing the anti-rotation means 12 between the bearing frame 6 and the bearing bush 8, the bearing bush 8 is kept in a non-idle state and a stable bearing function is exhibited. d. Since the shaft can be easily and quickly attached and detached, it is suitable as a shaft bearing structure for stirring the jet solder in a solder wave type soldering device for soldering an electronic component to a printed circuit board.

[0016]

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional front view illustrating a bearing structure of a removable shaft according to the present invention.

FIG. 2 is a vertical sectional side view taken along the line I-I in FIG.

FIG. 3 is a perspective view of a main part illustrating a soldering device to which the bearing structure of the detachable shaft of the invention is applied.

[Explanation of symbols]

 4 shaft 6 bearing frame 7 groove 8 bearing bush 9 receiving portion 10 collar 11 elastic body 12 free movement preventing means

Claims (2)

[Claims] 1. Grooves (7) adapted to receive the shaft (4) from above are formed in the bearing frames (6), (6), and
A bearing portion (9) adapted to be fitted from the outside of the bearing bush (8) with a collar is formed, while the bearing bushes (8), (8) are provided near both ends of the shaft (4). The bearing bushes (8) and (8) from the outside in a direction in which the flange is located on the outside, and the bearing bushes (8) and (8) are fitted to the shaft (4). Is a collar (10) near the end that is appropriately separated from the bearing bush (8),
(10) is fixed, and elastic bodies (11) and (11) are provided inside the collars (10) and (10) between the collars and the bearing bushes (8) and (8), respectively. A bearing structure for a removable shaft, characterized in that the bearing bushes (8), (8) are always kept in a tendency to be pressed inward. 2. A bearing structure for a removable shaft according to claim 1, wherein a play prevention means (12) is attached to the bearing frame (6) and the bearing bush (8).