JPS60161040A - Pressure insertion of shaft - Google Patents

Abstract

PURPOSE:To pressure insert with high accuracy by providing a center shaft section having conical end for positioning a pressure insertion member on the base section for holding said member while providing a shaft holder having resiliently shrinkable diameter on the movable section for holding pressure insertion member such as a shaft. CONSTITUTION:Prior to pressure insertion work, a resiliently shrinkable shaft holder 34 fitted with a pressure insertion member or a shaft 35 is inserted into a hole of pressure insertion shaft holding section 28 at the lower face of block 26 mounted on a dieset 22 at the movable side. Then a screw 32 is tightened to shrink the shaft holder 34 resiliently thus to hold the shaft 35 without damage. While a pressure inserting member 38 is mounted on a block 27 of dieset 23 at the fixed side to perform positioning by inserting the conical end of center shaft 39 into a hole of said member 38 and secure through a clamp 37. Under this state, a press 21 is lowered and further lowered against a spring 40 even after contact of the shaft 35 against the leading edge of center shaft 39 thus to pressure insert the shaft 35 accurately into the hole of pressure inserting member 38.

Description

[Detailed Description of the Invention] Technical Field> The present invention provides a method for attaching a shaft portion to a press-fit member by moving a movable portion that supports a shaft portion, which is a press-fit member, with respect to a base portion that holds the press-fit member. The present invention relates to a device for fully press-fitting, and in particular to a press-fitting device for a shaft portion that can press-fit a special precision shaft with high accuracy without causing damage to its surface.

<Prior Art> Generally, in the optical drive system of an optical news playback device represented by a compact disc, as shown in FIG. By moving the coil bobbin 2 up and down around this main shaft, the entire force song with the disk is performed, and by slightly rotating the coil bobbin 2 around this main shaft, tracking is performed. In order to drive such an optical system within the design specification values, the above-mentioned main shaft must be assembled with an accuracy within 8' with respect to the reference plane.

In addition, even in small VTRs such as 8 mm videos, the tape running system has become more compact and the assembly precision of the tape running guide has improved compared to current VTRs.
'i is more severe.

For example, the assembly accuracy of the tape guide shaft to the reference surface is 10 to ensure uniform tape tension of the running tape.
'The following is required.

Furthermore, in order to achieve low-friction contact with the bobbin or running tape, the shafts of these precision instruments are mirror-finished or coated with a thin film of Teflon, Lulon, or the like.

Therefore, in this type of precision shaft press-fitting device, it is important not only to perform high-precision press-fitting, but also to avoid damaging the shaft surface during press-fitting.

<Object> Therefore, the main object of the present invention is to provide a press-fitting device for a shaft part that can press-fit a shaft part with high precision without damaging the surface of the shaft part.

<Example> The present invention will be explained in detail below based on the drawings.

FIG. 2 is a front view of the press-fitting device according to the present invention.

In the figure, 21 is a press device, 22 is a screw set (movable part) that moves vertically in the figure by the drive of the press device, 23 is another screw set (base MS) on which the press-fitted member is placed, and 24 and 25 are These are guide shafts that stand up from the guide set 22, and one end of these guide shafts is fitted into a hole provided in the guide set 23, and as the guide set 22 moves in the vertical direction, it moves in the entire axial direction within the hole. It is designed to be able to slide. That is, this structure ensures that the perpendicularity of the movable goose set 22 to the reference plane of another goose set 23 is 4 or less.

Further, 26 is a block equipped with a press-fit shaft support portion to be described later;
Reference numeral 27 designates another block that supports the center shaft portion for positioning the hole of the press-fitted member. is being served.

The support part 28 of the press-fit shaft formed at the lower end of the block 26 has a lJ diameter part 29 as shown in FIGS. 3 and 4, and a hole 30 with a predetermined depth extends inward from the tip of this small diameter part. is formed. -Furthermore, as shown in the figure, a slot 31 of a predetermined width is formed vertically, and the diameter of the hole 30 can be adjusted by tightening the two screws 82 and 33. .

It is a cylindrical shaft holder that fits into the 34 holes 30, and its inner surface has a surface roughness of 0.8 μn1. Mirror finish of Rmax level is applied. Further, the inner diameter is approximately 0 to 5 μm larger than the diameter of the shaft 35 to be press-fitted, that is, the shaft 35 to be supported. 36 is a stopper.

Returning to FIG. 2, 87 is a clamp for fixing the press-fitted member 38 (see the base 4 gold in FIG. 1) placed on the block 27, and 89 is a clamp that aligns the hole of the press-fitted member 38 to the center. The tip of this center shaft has a conical shape as shown in the figure, and the base on the opposite side is supported by a coil spring 40. That is, the center axis 39 is.

It is fitted into a hole 41 at 27 degrees of the block, and is constantly biased upward in the figure by a coil spring 40.

Since the press-fitting device of the present invention has the above-described configuration, a stopper 361 is now installed in the hole 30 at the tip of the press-fitting shaft support N528.
! - Insert the shaft 35 to be press-fitted into the shaft holder 84 into the hole 30 as shown in FIG. 4(B). When the two screws 32 and 33 are tightened, the shaft holder 84 receives force from the outer periphery and its inner diameter is μm.
Elastically shrinks to order. The shaft 35I/'i inserted into the companion shaft holder 34 is supported to such an extent that it does not fall from the holder and without any error in perpendicularity. In this case, the inner surface of the shaft holder 34 has a mirror finish and supports the shaft 85 by elastic contraction on the order of μm, so that the shaft 35 can be supported without causing any damage to the surface.

In this way, after the shaft 85jf to be press-fitted is supported by the press-fitting shaft support part 28 of the movable side grip set 22, the press-fitted member into which this shaft 35 is then press-fitted is pressed into the hole of the fitting member 38. The tip of the center shaft 39 is inserted into the press-fit hole of the shaft 35, and therefore, due to the conical action of the center shaft, the center of the press-fit hole of the press-fit member 38 is automatically aligned with the center of the already supported shaft 35. It is supposed to be done.

Here, the press device 21' is activated to move the movable die set 2.
2 is lowered, the thread shaft 35 shown by the imaginary line in FIG. 2 comes into contact with the tip of the center shaft 39.

Furthermore, this shaft 35 descends while pushing down the center shaft 39 against the coil spring 40, and is press-fitted into the hole of the press-fitted member 38 with high precision as shown in FIG.

In this way, the shaft having undergone special surface treatment can be press-fitted into the press-fitted member with high precision without causing any damage to the surface. The press-fitting device has a base portion provided with a center shaft portion having a conical tip elastically supported in the axial direction in order to position the center of the press-fit hole of the press-fitted member, and a movable portion provided with a center shaft portion having a conical tip that is elastically supported in the axial direction in order to position the center of the press-fitting hole of the press-fitted member. Since the cylindrical shaft holder into which the tilted shaft is inserted and the s of the holder that supports this shaft holder are provided, the tilted shaft can be press-fitted into the press-fitted member with high precision without causing any damage. can.

[Brief explanation of drawings]

Fig. 1 is a diagram showing an example of an optical drive system, Fig. 2 is a front view of the press-fit device for tilting the shaft according to the present invention, Fig. 3 is an exploded perspective view of the press-fit shaft support, Fig. 4 K), ( 0) is a side view and a sectional view of the main part of the support part, and FIG. 5 is an explanatory diagram of the operation of the press-fitting device. 21 is a press device, 22 and 23 are die centers, 24 and 25 guide shafts, 26 and 27 r/i blocks, 28 is a press-fit shaft support, 34 is a shaft holder, 35 is a shaft, 37 is a clamp, and 39 is a center shaft. Agent Patent attorney Aihiko Fukushi (2 others) (a) Figure 4

Claims (1)

[Claims] 1. In an apparatus for press-fitting a shaft portion of a press-fitting member in its entirety by moving the entire movable part that supports the shaft portion, which is a press-fitting member, with respect to a base portion holding the press-fitting member, The base portion is provided with a center shaft portion having a conical tip that is elastically supported in the axial direction in order to position the center of the press-fit hole of the press-fit member, and the movable portion is provided with a center shaft portion of the press-fit member. 1. A press-fitting device for a shaft portion, comprising: a cylindrical shaft holder into which the shaft holder is inserted, and a press-fit shaft support portion comprising means for supporting the shaft holder and elastically contracting the inner diameter of the holder.