JPS59164417A - Bush drawing structure - Google Patents

Abstract

PURPOSE:To easily draw out a bush by providing a bush drawing structure comprising a drawing plate inserted into the inner part of the bush and a drawing bolt, and screwing the drawing bolt. CONSTITUTION:The forward end of a drawing bolt 8 is engaged with a tapped hole 7 bored through a drawing plate 6. With this drawing tool 9, the drawing plate 6 inserted into the space portion 10 at the inner part of a bush 4, and the forward end of the drawing bolt 8 is brought into contact with the innermost wall 3a of a shaft hole 3. When the drawing bolt 8 is rotated in the screw- in direction, the drawing plate 6 is moved outward. At that time, if one place of the drawing plate 6 is brought into contact with the innermost end surface of the bush 4, the bush 4 is pushed outward by the drawing plate 6. In such draw-out structure, the bush can be easily drawn out by simple operation.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a structure for extracting a bushing inserted between a shaft and a shaft hole in, for example, a center bin support of a tractor.

Conventionally, when a bushing becomes worn and needs to be replaced, it is difficult to remove the bushing, which requires time and effort. The present invention has been made for the purpose of providing a bushing removing structure that can easily pull out such a bushing. It consists of a draw-out plate that is inserted and passed through a screw hole, and a draw-out bolt that is screwed into the screw hole and whose tip is abutted against the hole wall on the back side of the bushing. The punching plate is moved in the pulling direction by screwing in, and the bushing is pushed out.

The configuration of the present invention will be described below based on an embodiment implemented in a center bin support portion of a tractor.

Figure 1 shows the installation structure of the center bin (1) as a shaft. In the figure, 121 f2) is a pair of front and rear bearing brackets that are installed on the fuselage side, and these two bearing brackets (f2) +2) are formed with shaft holes (31 (31) facing each other, and these shaft holes [31+31
, the end of the center bin (1) has a bush (41+4
It is inserted via 1. (5) is a front axle that supports the front wheels. Now, in order to extract the bushing (4) from the support part of the center pin fil as shown in FIG. 1, the center pin fil is first extracted. This is done using a tool as shown in Figure 2.

That is, in this FIG. 2, (6) is a disc-shaped punching plate formed with a smaller diameter than the inner diameter of the bush (4), and a hole passes through the punching plate (4) in the thickness direction. The tip of a pull-out bolt (8) is screwed into the provided screw hole (7). The punching tool (9) formed in this way
) first pulls out the center pin fl) as described above, and then inserts the punching plate (4) from the outside in the direction in which the bushing (4) is pulled out, as shown in FIGS. ), and is inserted into the space (10) on the back side of the bush (4), and the tip of the draw bolt [8] is inserted into the back wall (3a) of the shaft hole (3). When the draw bolt (8) is abutted and then rotated in the screwing direction, the draw plate (6) moves outward accordingly. At that time, if one part of the punching plate +61 is brought into contact with the rear end surface of the bushing (4), the bushing (4) is pushed outward by the punching plate (6), and in this way, This is for extracting the bush (4). Therefore, with this extraction structure, the extraction bolt (8) can be easily extracted by simply rotating the bolt (8), and the bushing (4) can be easily extracted without requiring much force. Work can be done extremely quickly.

Figures 5 and 6 show other extraction structures. Plate (6
) is inserted, and when removing it, after removing the center pin (1), insert only the extraction bolt (8) from the outside of the bushing (4), and insert its tip into the previously inserted extraction plate ( 6) into the screw hole (7),
It is extracted in the same manner as in FIG. 3 above. In this embodiment, the outer diameter of the punching plate (6) is larger than the inner diameter of the bushing (4) and approximately the same diameter as the outer diameter of the bushing (4).

FIGS. 7 and 8 show still another extraction structure of the bush (4). In this figure as well, the punching plate (6) has been inserted in advance into the space (10) on the back side (7) of the center pin fil.
) has no screw hole (7) formed therein. In Fig. 5, the bearing bracket (2) has a shaft hole (3).
) From the outside, which is the back side, insert the shaft hole (3) and the back wall (3
a) and a screw hole (
A steel ball (12) is inserted into the screw hole (11), and a holding pole (13) is inserted from the outside of the screw hole (11). It is in contact with the back surface of the punching plate (6) inserted in advance. In such a structure, in order to pull out the bush (4), first pull out the center pin (1) in the same way as above, then pull out the holding bolt (13) and attach it to another long bolt (8). Replace it and insert it into the screw hole (11), abut the tip of the draw bolt (8) against the steel ball (12), and insert the draw plate (6) through the steel ball (12) into the bush (4). ) in the direction of extraction of the bushing (4), and the bushing (4) is pushed out by the extraction plate (6).

In addition, in the present invention, the back wall (3a) of the shaft hole (3) against which the tip of the extraction bolt (8) comes into contact is connected to the bearing bracket (
In addition to the wall surface that is integral with 2), it may be a wall surface that is closed by another member.

The bushing extracting structure of the present invention is as described above, and according to the present invention, the bushing can be extracted by an extremely simple operation of rotating the extracting bolt screwed into the extracting plate on the rear side of the bushing. As mentioned above, the force required to pull out the bushing is not very strong, and the bushing can be pulled out in a short time with an extremely simple operation.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view showing the structure of the center bin mounting section on a tractor, Fig. 2 is a perspective view of the bushing removal tool of the present invention, and Fig. 3 shows the installation state of the bushing removal tool shown in Fig. 2. The vertical cross-sectional view shown in FIG. 4 is also a cross-sectional view, FIG.
6 and 6 show other bushing removal structures, and FIG. 5 is a longitudinal cross-sectional view of the state in which the center bin is installed.
FIG. 6 is a longitudinal cross-sectional view showing the state in which the extraction bolt is installed;
7 and 8 show still another structure for removing the bushing. FIG. 7 is a longitudinal sectional view showing the structure before the center pin is removed, and FIG. 8 is a longitudinal sectional view showing the structure before the center pin is removed. It is a longitudinal cross-sectional view showing a state in which bolts are attached. f3)-shaft hole, (3a)-shaft hole back wall, (4)-button, (6)-pull plate, f71-screw hole, (8)-・
-Extraction bolt. Patent Applicant Yanmar Diesel Co., Ltd. Representative Patent Attorney Hisayuki Tarumoto Figure 5 Figure 7] O Figure 6 Figure 8 Ja 4

Claims (1)

[Claims] A punching plate is inserted into the back side of the bushing that has penetrated into the large circle and has a screw hole passed through it, and is screwed into the screw hole, and its tip is butted against the hole wall on the back side of the bushing. The bushing removal structure has a bushing removal structure in which the drawing bolt is hollow, and when the drawing bolt is further screwed in, the drawing plate moves in the drawing direction and the bushing is pushed out.