JPH0420095B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a resin sleeve bearing used under grease lubrication.

In automobiles and the like, a winding bush for a bearing is usually used for a shaft that reciprocates in conjunction with steering wheel operation, and a resin sleeve is attached to the sliding surface of the shaft of this winding bush to prevent noise generation.

When attaching a resin sleeve to the inside of the metal cylinder that makes up the wood bushing body using the in-jet extension method, the shape of the groove for retaining grease provided on the inner circumferential surface of the resin sleeve to improve the abrasion resistance of the resin sleeve part is the in-jet extension type. For convenience of mold cutting, as shown in FIGS. 1 and 2, when the groove 3 extends linearly in the axial direction, at least one end of the groove 3 reaches one end of the resin sleeve 2. It had to be molded into an open shape. In the figure, 1 is a metal cylinder. However, due to this open shape, the grease filled in the groove 3 is absorbed by the axis A indicated by the two-dot chain line in FIG. 2 in the operating state.
Due to the reciprocating motion in the axial direction, the resin is gradually discharged from the open side of the groove 3 to the outside of the resin sleeve 2, causing a problem of poor lubrication.

As a countermeasure against this problem, as shown in FIGS. 3 and 4, grooves 3' are provided in a spiral shape on the inner circumferential surface of the resin sleeve 2. The motion of the injection type was complicated, which had an adverse effect on the dimensional accuracy required for a bearing. Furthermore, one end of this groove 3' reaches one end of the sleeve 2 and is open, making it an incomplete measure to prevent grease from being discharged during operation.

The present invention is intended to solve the above problem, and its purpose is to discharge the grease filled in the groove of the resin sleeve to the outside of the resin sleeve by reciprocating the shaft fitted in the resin sleeve in the axial direction. A method of manufacturing a resin sleeve bearing that improves lubrication performance by preventing the inner circumferential surface of the resin sleeve from being open to the end surface of the sleeve without complicating the operation of the injection extension type. An object of the present invention is to provide a method for manufacturing a resin sleeve bearing having a groove for retaining grease.

Therefore, in the resin sleeve bearing of the present invention, a plurality of grooves extending in the axial direction and closed at both ends are arranged in parallel at appropriate intervals in the circumferential direction on the inner circumferential surface of the resin sleeve that is attached to metal. In a method of manufacturing a resin sleeve bearing, a first mold is set in a metal cylinder in which a plurality of depressions are arranged side by side at appropriate intervals in the circumferential direction on the inner peripheral surface, and the mold body of the first mold is A plurality of rod-shaped intervening bodies protruding from each other are retractably accommodated in each recess of the metal cylinder, and the inner circumferential surface of the metal cylinder and the first
A cylindrical body provided in a second mold is inserted into the inside of the metal cylinder with a space between each intervening body of the mold, and the second mold is set. A plurality of protrusions for forming grooves provided in the first mold are positioned with gaps between them and respective intervening bodies of the first mold, and a resin is injected into the formed voids and hardened, and then the first mold is The method is characterized in that the mold and then the second mold are pulled out in order.

Embodiments of the present invention will be described below with reference to the drawings.

Example 1 In FIGS. 5 and 6 showing the resin sleeve bearing manufactured in this example, 11 is a metal cylinder, and a resin sleeve 12 is disposed on a predetermined inner circumferential surface 11a of this metal cylinder 11. It is attached using an injection mold. On the inner circumferential surface of the resin sleeve 12, a plurality of grooves 13 for retaining grease, which extend linearly in the axial direction and are closed at both ends, are arranged in parallel at regular intervals in the circumferential direction. This resin sleeve 12 is made of engineering plastics such as nylon and polyacetal. In the figure, reference numeral 14 denotes a recess formed across the inner circumferential surface 11a of the metal cylinder 11 at a position corresponding to each groove 13, taking into consideration the ease with which the mold can be pulled out, which will be described later. In addition,
Size and number of grooves 13 and adjacent grooves 13,1
The interval between 3 can be arbitrarily determined.

In the resin sleeve bearing configured in this way, both ends of each groove 13 are closed,
Since the ends 12a and 12b of the resin sleeve 12 are not reached, even if the shaft A shown by the two-dot chain line in FIG. The grease will not be discharged outside the resin sleeve 12 and will not cause poor lubrication. Therefore, smooth lubrication can be achieved.

FIGS. 7 to 10 show the molds used in this example.

The first mold 15 shown in FIGS. 7 and 8 has a mold surface 1 formed by recessing the entire mold in order to form a flange-like end 12a of the resin sleeve 12.
5a, and a plurality of rod-shaped intervening bodies 16 which can be inserted into and removed from each of the plurality of depressions 14 of the metal cylinder 11 are arranged in an annular shape at regular intervals so as to protrude from the mold surface 15a. Although not shown, the mold surface 15a is provided with at least one injection port through which the synthetic resin is injected.

The second mold 17 shown in FIGS. 9 and 10 is
A cylindrical body 1 has a mold surface 17a formed by recessing the mold body to form the flange-shaped other end 12b of the resin sleeve 12, and protrudes from the mold surface 17a.
A plurality of intervening bodies 1 of the first mold 15 are disposed on the circumferential surface of the mold 8.
A plurality of protrusions 19 extending linearly in the axial direction are arranged in parallel at regular intervals in the circumferential direction at positions corresponding to the respective positions of the protrusions 19 . Each protrusion 19 is for forming the groove 13 of the resin sleeve 12, and is for forming the groove 13 of the resin sleeve 12.
When the cylindrical body 18 of the mold 17 is inserted into the space formed by the annularly arranged intervening bodies 16 of the first mold 15, a gap is formed between the cylindrical body 18 and the intervening bodies 16. Note that the end surface 18a of the cylindrical body 18 is
It is adapted to come into contact with the recessed mold surface 15a of the first mold 15.

In order to manufacture a resin sleeve bearing using the first mold 15 and the second mold described above, first
As shown in FIG. 1, the corresponding intervening body 16 of the first mold 15 is inserted into each recess 14 of the metal cylinder 11 from one side, and the intervening body 16 is accommodated so as not to protrude from the inner circumferential surface 11a of the metal 11. Then, the first mold 15 is set.

Next, the protrusions 19 of the second mold 17 are placed at positions corresponding to the respective positions of the intervening bodies 16 of the first mold 15.
Insert the cylindrical body 18 of the second mold 17 in the direction of the arrow in FIG. 11 into the space formed by the annularly arranged intervening body 16 of the first mold 15 so that As shown in FIG.
A is brought into pressure contact with the mold surface 15a of the first mold 15, and the second
Set the mold 17. At the time of this setting, a gap is formed between the circumferential surface of the cylindrical body 18 of the second mold 17 and the inner circumferential surface 11a of the metal cylinder 11, and a gap is formed between the protrusion 19 of the second mold 17 and the first A gap is also formed between the mold 15 and the intervening body 16 .

Then, an engineering plastic such as nylon or polyacetal is injected into the gap from the injection port of the first mold 15 and hardened.
After curing, the first mold 15 was first pulled out from the metal cylinder 11, and then the second mold 17 was pulled out from the metal cylinder 11, thereby obtaining the resin sleeve bearing shown in FIGS. 5 and 6. Note that when pulling out the second mold 17, the resin sleeve 1 shown in FIGS.
A corresponding portion of the second groove 13 is elastically deformed toward the recess 14 and does not inhibit the extraction of the protrusion 19 of the second mold 17.

Example 2 Next, a resin sleeve bearing manufactured in a second example will be explained with reference to FIGS. 13 to 15. In FIGS. 13 to 15, 21 is a metal cylinder, and the inner circumferential surface 2 of this metal cylinder 21 is
A resin sleeve 22 is mounted on 1a using an injection mold, which will be described later. In the inner peripheral surface of the resin sleeve 22, there is a groove 23 for retaining grease that extends in the axial direction and is closed at both ends.
are arranged in parallel at regular intervals in the circumferential direction.
In addition, the size and number of grooves 23 and the adjacent grooves 2
The interval between 3 and 23 can be arbitrarily determined. The resin sleeve 22 itself is made of engineering plastics such as nylon and polyacetal.

A plurality of depressions 24 are formed on the inner circumferential surface 21 a of the metal cylinder 21 at positions corresponding to the grooves 23 .
It is provided extending to one end of the portion forming part 1a. A hollow resin layer 26 having a substantially semicircular cross section is formed so as to form a void 25 in each depression 24 .

In the resin sleeve bearing configured in this way, both ends of the groove 23 are closed and do not reach both ends 22a and 22b of the resin sleeve 22, so the resin sleeve 22 is closed as in the first embodiment.
Even when the shaft A (indicated by the two-dot chain line in FIG. 14) fitted into the groove 23 reciprocates, the grease filled in the groove 23 is retained and smooth lubrication can be achieved.

Next, a method for manufacturing this resin sleeve bearing will be described.

FIGS. 16 to 19 show the molds used in this example. In FIGS. 16 and 17, 27 is the first mold, and 28 is the first mold 2.
This is the second mold superimposed on 7. Second mold 2
8 is the second mold 1 shown in FIGS. 9 and 10.
7, the resin sleeve 22
The mold surface 28a is recessed to form a flange-like end 22b of the mold surface 28a.
A is provided with a cylindrical body 29, and on the circumferential surface of the cylindrical body 29, a plurality of protrusions 30 for forming a plurality of grooves 23 of the resin sleeve 22 are arranged in parallel at regular intervals.

The first mold 27 is connected to each protrusion 30 of the second mold 28.
A rod-shaped intervening body 3 that is overlapped with a gap between
1 are arranged side by side in a cylindrical mold main body at intervals, and the second mold 28 itself is inserted into this main body. Note that the second mold 28 includes:
A notch 28b is formed to guide the movement of each intervening body 31 of the first mold 27, and the mold surface 28a is formed with a cutout 28b.
Although not shown, at least one injection port is provided through which resin for forming the resin sleeve 22 is injected.

Matching mold 32 shown in FIGS. 18 and 19
The end surface 29a of the cylindrical body 29 of the second mold 28 is brought into contact with the recessed mold surface 32a, and the resin sleeve 2 is
This is for forming the other end 22b of 2.

In order to manufacture a resin sleeve bearing using the first mold 27, the second mold 28, and the mating mold 32, first, as shown in FIG.
The intervening body 31 of the mold 27 is inserted into each depression 2 of the metal cylinder 21.
4 with a gap, and then the second mold 28
The notches 28b (see FIG. 16) are fitted into the corresponding intervening bodies 31, and the second mold 28 is moved so that each protrusion 30 and the corresponding intervening bodies 31 have a gap and form a cylindrical body. The first mold 27 and the second mold 28 are set in the metal cylinder 21 so that there is a gap between the peripheral surface of the metal cylinder 29 and the inner peripheral surface 21a of the metal cylinder 21. Next, the mating mold 32 is moved in the direction of the arrow in FIG.
9a, and set the mating mold 32 in the metal cylinder 21, as shown in FIG.

Engineering plastics such as nylon or polyacetal are injected from the injection port of the second mold 28 into the void formed by the above-described operation and hardened. After curing, first the first mold 27 is pulled out from the metal cylinder 21, then the mating mold 32 is pulled out, and then the second mold 28 is pulled out, thereby forming the resin sleeve bearing shown in FIGS. 13 and 14. Obtained. Note that when the second mold 28 is pulled, since the metal cylinder 21 is provided with a recess, a portion corresponding to the groove 23 of the resin sleeve 22 shown in FIGS. 13 and 14 is elastically deformed toward the cavity 25. Therefore, the extraction of the protruding portion 30 of the second mold 28 is not hindered.

As explained above, according to the resin sleeve bearing of the present invention, a groove for retaining lubricating oil with both ends closed is provided on the inner circumferential surface of the resin sleeve, so that the shaft fitted into the resin sleeve is aligned in the axial direction. Even during reciprocating motion, the lubricating oil such as grease filled in the groove is not discharged, and the lubrication performance can be significantly improved compared to the conventional one.

Further, according to the method of the present invention, after forming a groove for retaining lubricating oil in the resin sleeve using the intervening body of the first mold accommodated in the recess of the metal cylinder and the protrusion provided on the second metal cylinder, the metal cylinder is When the protrusion of the second mold is pulled out after the intervening body of the first mold is pulled out from the recess of the mold, the groove-equivalent portion of the molded resin sleeve is elastically deformed toward the recess of the metal cylinder, so that the second mold is easily removed. The protrusion of the mold can be pulled out, and a groove for retaining lubricating oil that does not reach the end of the sleeve can be easily formed on the inner circumferential surface of the resin sleeve.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view showing a conventional resin sleeve bearing, Fig. 2 is a sectional view taken along the - line of Fig. 1, Fig. 3 is a front view showing another conventional resin sleeve bearing, and Fig. 4. is a sectional view taken along the - line of FIG. 3, FIG. 5 is a longitudinal sectional view showing the resin sleeve bearing according to the first embodiment of the present invention, and FIG. 6 is a sectional view taken along the - line of FIG. Figure 7 is a front view showing the first mold used to manufacture the items shown in Figures 5 and 6, Figure 8 is a side view showing the first mold, and Figure 9 is the same as the one shown in Figure 5. and the sixth
A front view showing the second mold used to manufacture the item in the figure, FIG. 10 is a side view showing the second mold,
11 and 12 are diagrams showing one embodiment of the method of the present invention, and FIG. 11 shows a first embodiment of the method of the present invention.
FIG. 12 is a cross-sectional view showing a state in which a second mold is set in the metal cylinder in which the first mold is set, and FIG. 13 is a cross-sectional view showing a state in which a second mold is set in a metal cylinder in which a first mold is set. 14 is a sectional view taken along the - line in FIG. 13, FIG. 15 is a sectional view taken along the - line in FIG. 14, and FIG. 16 is a sectional view taken along the - line in FIG. 14. A front view showing a state in which a first mold and a second mold used for manufacturing the item shown are overlapped;
FIG. 7 is a side view showing the first mold and second mold superimposed, FIG. 18 is a front view showing the combined mold, FIG. 19 is a side view showing the combined mold, FIGS. FIG. 21 is a diagram showing another embodiment of the method of the present invention, in which FIG. 20 is a sectional view showing a state in which the first mold and the second mold are set in a metal cylinder, and FIG. FIG. 3 is a sectional view showing a state in which the mold is set in alignment with the metal cylinder in which the mold and the second mold are set. DESCRIPTION OF SYMBOLS 11...Metal cylinder, 11a...Inner peripheral surface of metal cylinder, 12...Resin sleeve, 13...Groove, 14...
... Depression, 15 ... First mold, 16 ... Interposition body, 1
7...Second mold, 18...Cylindrical body, 19...Protrusion part.

Claims (1)

[Scope of Claims] 1. A plurality of grooves extending in the axial direction and closed at both ends are provided at appropriate intervals in the circumferential direction on the inner circumferential surface of the resin sleeve attached to the inner circumferential surface of the metal cylinder. In the method for manufacturing resin sleeve bearings arranged in parallel, a first mold is set in a metal cylinder in which a plurality of depressions are arranged in parallel at appropriate intervals in the circumferential direction on the inner peripheral surface,
A plurality of rod-shaped intervening bodies protruding from the mold body of the first mold are each retractably housed in each recess of the metal cylinder, and the inner circumferential surface of the metal cylinder and the first mold are A cylindrical body provided in a second mold was inserted into the inner side of the metal cylinder with a space between each intervening body, and the second mold was set, and a cylindrical body was provided on the circumferential surface of the cylindrical body of the second mold. A plurality of protrusions for forming grooves are respectively positioned with a gap between them and each of the intervening bodies of the first mold, and a resin is injected into the formed cavities and hardened. A method for manufacturing a resin sleeve bearing, comprising sequentially pulling out a mold and then the second mold.