JPH0425539Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a rotation prevention structure for a guide bearing that guides the linear movement of a linear shaft.

Conventional technology In the case of a linear motion shaft that needs to be linearly extended and contracted by restricting its rotation, such as a telescopic robot arm, it is necessary to restrict the rotation of the bearing that guides this linear motion shaft. There is. For example, FIGS. 5 and 6 show a robot equipped with a telescoping arm as an example of a conventional linear motion axis.
is a pivot shaft 3 provided on the base 2 so as to be movable up and down.
, a front-rear shaft 4 provided substantially horizontally on the upper part of the pivot shaft 3, and an annular shaft 4 protruding from the front-rear shaft 4 toward the front side (to the right in FIG. 5) in a substantially horizontal direction. A cylindrical bearing case 6 that accommodates guide bearings 5, 5, and is inserted through both guide bearings 5, 5 in this bearing case 6 and guided so as to extend and contract linearly,
It is provided with a telescoping arm 7 having a hand 7b attached downward through a neck bending unit 7a at its tip.

The pivot shaft 3 is supported by an elevating unit 8 provided on the base 2, and is driven vertically up and down by an elevating drive motor 9, and the height of the longitudinal shaft 4 is adjusted by driving the pivot shaft 3 up and down. Further, it is horizontally driven to swing by a swing drive motor 10.

On the other hand, the telescoping arm 7 is telescopically driven by a telescoping drive motor 11 having a drive shaft parallel to the front-rear axis 4, and the portion of the telescoping arm 7 extending from the end of the bearing case 6 has a bellows shape. The guide bearing 5 is covered with a dustproof cover 12 which is expandable and retractable to prevent dust from entering the inner periphery of the guide bearing 5.

The annular guide bearings 5, 5 housed in the cylindrical bearing case 6 have a key groove 6a formed on the inner peripheral surface of the bearing case 6, and a key groove 6a at a position corresponding to the key groove 6a. A detent key 13 is inserted into a key groove 5a formed on the outer circumferential surface of each guide bearing 5 to restrict rotation of each guide bearing 5 with respect to the bearing case 6, and the telescopic arm 7 is It is guided so that it expands and contracts linearly without rotation.

Problems to be Solved by the Invention In the telescopic arm 7 of the conventional robot 1 described above, the key groove 6a on the side of the bearing case 6 into which the detent key 13 for regulating the rotation of the guide bearings 5, 5 is inserted. is formed by cutting a narrow, deep groove into the inner peripheral surface of the cylindrical bearing case 6 from its front end (right end in FIG. 6). Therefore, in order to form this keyway 6a, a special tool is required to machine a narrow and deep groove, and in order to ensure the width accuracy of this groove, skilled technology and many machining man-hours are required. The problem was that it was needed.

This idea was created in view of the above problems.
The object of the present invention is to provide a locking structure for a linear motion guide bearing, which has a key insertion hole that is easy to process and has high precision, and also allows easy assembly of a locking key and a guide bearing to a bearing case.

Means for Solving the Problems As a means for solving the above-mentioned problems, this invention is based on an annular guide bearing that restricts the movement of the linear motion shaft inserted therethrough in the rotational direction and slidably guides it in the axial direction. In the anti-rotation structure of a linear motion guide bearing that fixes the guide bearing so as not to rotate with respect to a bearing case in which the guide bearing is inserted and held, a through hole is formed in the bearing case and penetrates from the outer surface to the inner surface of the bearing case, and , a mounting seat is formed on the outer surface of the bearing case around the opening of the through hole, and a recess is formed on the outer periphery of the guide bearing at a position corresponding to the through hole when inserted into the bearing case. The stepped key is formed by integrating an insertion portion having a shape corresponding to the through hole and a mounting portion formed at an end of the insertion portion. The stepped key is fitted into the recess of the bearing, and the mounting portion of the stepped key is fixed in close contact with the mounting seat.

Function In this invention, a through hole is formed as the key insertion part in the bearing case, and the detent key has an insertion part and a mounting part integrally formed at the end thereof, and the insertion part is inserted into the through hole. The rotation of the guide bearing is regulated by inserting it into the guide bearing and fitting its tip into a recess formed on the outer circumference of the guide bearing. At the same time, the mounting part formed at the end of the key is tightly fixed to the mounting seat on the outer surface of the bearing case, which prevents rattling and seals the through hole, effectively preventing dust from entering. is prevented.

Embodiment Hereinafter, an embodiment in which the locking structure for a linear motion guide bearing according to the present invention is applied to a locking structure for a linear motion guide bearing of a telescopic arm of a robot will be described with reference to FIGS. 1 to 4. In addition,
Components that are the same as those of the conventional example shown in FIGS. 5 and 6 are designated by the same reference numerals, and detailed explanation thereof will be omitted.

The telescoping arm 7 of the robot 20 is housed in a cylindrical bearing case 26 which is provided so as to protrude forward (to the right in FIG. 1) in a substantially horizontal direction from the front-rear shaft 4 provided at the top of the rotating shaft 3. It is inserted into annular guide bearings 25, 25 that guide the linear operation of the housed spline bearings, etc., and these guide bearings 25, 25,
The protrusions 7c formed on the outer peripheral surface of the telescoping arm 7 in parallel to the axis are engaged with guide grooves 25b formed in the inner surface of each guide bearing 25 in parallel to the axis, so that the telescoping arm 7 is guided to extend and contract linearly. ing. Further, the annular guide bearings 25, 25 that guide the linear motion of the telescopic arm 7 have a long keyway 25a in a direction parallel to the axis at a predetermined position on the outer peripheral surface thereof, and the cylindrical bearing case 26 A bearing accommodating portion 26b whose inner periphery is expanded to have approximately the same diameter as the outer diameter of the guide bearing 25.
Both guide bearings 25, 25 are housed in a spaced-apart state with a bearing collar 27 interposed between them, and guide grooves 25b formed on the inner peripheral surfaces of both guide bearings 25, 25 are aligned in a straight line. They are arranged in a line.

On the other hand, on the outer peripheral surface of the bearing case 26, each key groove 25a of the guide bearings 25, 25 is
Key attachment holes 26a, 26a are formed through the bearing case 26 from the outer circumferential side to the inner circumferential side at positions in the outer circumferential direction of the bearing case 26, respectively. Each key mounting hole 26a is formed linearly by milling or the like in a direction parallel to the axis from the outer circumferential side of the bearing case 26, and each key mounting hole 26a has an opening on the outer circumferential side of the bearing case 26. There is a flat key mounting seat 2 on the periphery.
6c is formed.

Stepped keys 30, 30 for preventing rotation of the guide bearing 25 are inserted into the key mounting holes 26a, 26a.

This stepped key 30 has a key mounting seat surface 26c formed on the outer peripheral surface of the bearing case 26.
a rectangular plate-shaped mounting portion 30a that is approximately the same width as the width of the key mounting hole 26a and slightly longer than the length of the key mounting hole 26a;
Each stepped key 30 has a T-shaped cross section and an insertion part 30b formed perpendicularly from the center of one side of the mounting part 30a with a width that fits into the key mounting hole 26a without a gap. , its insertion portion 30b
are inserted into each key mounting hole 26a from the outer circumferential side of the bearing case 26, and the respective insertion portions 30b
The distal end of the guide bearing 25 is fitted into the key groove 25a of each guide bearing 25 arranged so as to face the inner peripheral surface of each key mounting hole 26a of the bearing case 26, and the mounting portion 30a on the base end side is inserted. The side surface of the portion 30b is brought into close contact with the mounting seat surface 26c, and the four corners of the mounting portion 30a are fastened to the mounting surface 26c with fixing bolts 31, respectively.

Therefore, the housing part 2 of the bearing case 26
The guide bearings 25, 25 in 6b are stepped keys 3 whose proximal mounting portions 30a are respectively fixed to the mounting seat surface 26c of the bearing case 26.
0 and 30 are connected to respective key grooves 25a and 2
5a, rotation within the accommodating portion 26b is restricted, and the telescopic arm 7 inserted through each guide bearing 25 is guided so as to extend and retract linearly without rotating.

In addition, in the guide bearing rotation prevention structure of the telescopic arm of the above embodiment, the cross section T is provided with the mounting portion 30a and the insertion portion 30b as the rotation prevention key.
Since the stepped key 30 is used, the key can be easily installed and fixed, and the working time can be shortened. Further, the stepped key 30 is attached to the mounting portion 30.
Since the stepped key 30 and the insertion portion 30b are integrally formed, there is no wobbling of the stepped key 30 itself, and the wobbling of each guide bearing 25 is also effectively prevented.

In addition, since the mounting portion 30a of the stepped key 30 seals the key mounting hole 26a opened on the outer peripheral surface of the bearing case 26, the key mounting hole 26a is closed.
Intrusion of dust, etc. from a is effectively prevented.

In addition, in the guide bearing rotation prevention structure of the telescopic arm of the above embodiment, the stepped key 3 in which the mounting portion 30a and the insertion portion 30b are integrally formed is used.
0 was used, but a lid body is used instead of the attachment part 30a, and a plate-shaped detent key separate from the lid body is inserted into the key attachment hole 26a, and the outer peripheral side of the key attachment hole 26a is connected to the lid. Almost the same effect can be obtained even if the base end side of the detent key on the plate is fixed with the cover body to provide a tight seal.

In addition, although the above embodiment describes the anti-rotation structure of the guide bearing that guides the linear motion of the telescopic arm of a robot, it can also be easily applied to the anti-rotation structure of the guide bearing of the linear motion axis of various other devices. can.

Effects of the invention As explained above, this invention has been developed to prevent rotation of a linear motion guide bearing for regulating the rotation of the guide bearing that guides the inserted linear motion shaft with respect to the bearing case. A through hole that penetrates to the inner circumference side is formed, and a recess is formed on the outer circumference of the guide bearing at a position corresponding to the through hole when the bearing case is inserted, and a detent key is inserted into the through hole from the outer circumference side of the bearing case. The tip of the key is inserted into the recess and the proximal end is fixed to the outer periphery of the bearing case, and the key insertion point formed in the bearing case is a through hole that can be machined from the outer periphery of the bearing case. Machining becomes easier, the precision of machining the key insertion location can be increased, and the time required for the machining can also be shortened. In addition, the detent key can be inserted into the through hole from the outer circumference of the bearing case.
The anti-rotation key and guide bearing can be easily assembled to the bearing case, greatly reducing processing and assembly man-hours.Furthermore, the key has a mounting part formed integrally at one end that is tightly attached to the mounting seat of the bearing case. Since the guide bearing is fixed in place, it is possible to prevent the guide bearing from rotating without causing play.

[Brief explanation of the drawing]

Figures 1 to 4 show an embodiment of this invention. Figure 1 is an overall view of a robot implementing the anti-rotation structure of this invention, and Figure 2 is an enlarged sectional view of the main part of Figure 1. , Fig. 3 is a plan view of Fig. 2, Fig. 4 is a sectional view taken along the line - - of Fig. 2, Figs. 5 and 6 show conventional examples, and Fig. 5 shows an example of a conventional robot. The overall view shown in FIG. 6 is an enlarged sectional view of the main part of FIG. 5. 3... Rotation axis, 4... Front and rear axis, 20... Robot, 25... Guide bearing, 25a... Key groove, 26... Bearing case, 26a... Key mounting hole (key groove), 26b... Accommodation Part, 26c
... Key mounting seat, 30 ... Stepped key, 30
a... Attachment part, 30b... Insertion part, 31... Fixing bolt.

Claims (1)

[Scope of utility model registration request] An annular guide bearing that restricts the rotational movement of the inserted linear shaft and allows it to slide in the axial direction is fixed so as not to rotate relative to the bearing case in which the guide bearing is inserted and held. In the anti-rotation structure for a linear motion guide bearing, a through hole is formed in the bearing case that penetrates from the outer surface to the inner surface of the bearing case, and a mounting seat is formed around the opening of the through hole on the outer surface of the bearing case, Further, a recess is formed on the outer circumference of the guide bearing at a position corresponding to the through hole when inserted into the bearing case,
Of the stepped keys that integrate an insertion part with a shape corresponding to the through hole and a mounting part formed at the end of the insertion part, the insertion part is inserted into the through hole and the tip thereof is attached to the guide bearing. A locking structure for a linear motion guide bearing, characterized in that the stepped key is fitted into the recess and the mounting portion of the stepped key is fixed in close contact with the mounting seat.