JPH0623679A - Rotary bed - Google Patents

Abstract

PURPOSE:To prevent entrance of any foreign matter into the core oscillation preventing and rotational slide part of a rotary bed. CONSTITUTION:Under and upper rings 1 and 2 having taper-form peripheral walls 13 and 23, engageable with each other, and guide grooves 15 and 25, respectively, formed in the periphery walls are rotatably engaged with each other through a number of balls 4. The ball 4 is held by means of retainers 3 made of synthetic resin, and the lip parts 33 and 33 protruded from the retainer 3 are brought into slide contact with the peripheral walls of the under and upper rings 1 and 2. Thus, since the ball 4 is rolled in a state to be fitted in the guide grooves 15 and 25 of both rings, displacement in a core between the under and upper rings 1 and 2 is not produced, entrance of any foreign matter into a gap between the ball 4 and the guide groove is prevented by means of the lip parts 33 and 33 protruded from the retainer 3, and smooth rotation can be maintained for a long period.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turntable used when an article is placed and rotated to perform work.

[0002]

2. Description of the Related Art The applicant has previously proposed a turntable for rotating a cargo handling pallet (6) as shown in FIGS.
(Jitsuko Sho 62-2178). This consists of a plurality of rotary bearings on the annular vertical wall (17) of the annular underring (1) with an L-shaped section.
Place (5) freely in the vertical plane and under ring
Above (1), a ring-shaped upper ring (2) having an annular upper plate (27) and a vertical peripheral wall (29) bent downward from the peripheral edge of the upper plate and having an L-shaped cross section is covered. Has been done.

A ball (53) is rotatably supported at the tip of a support shaft (51) of the rotary bearing (5), and an under ring
In contrast to (1), when the runout of the upper ring (2) occurs, the ball (53) hits the vertical peripheral wall (29) of the upper ring (2) and rolls to reduce friction.

[0004]

The above-described rotary table has many advantages because it is lightweight and has a simple structure.
It took a lot of time to attach the support shaft (51) for supporting the rotary bearing (5) and to attach the ball (53) to the tip of the support shaft so that the ball (53) could rotate freely and could not escape.

Further, due to the structure of assembly, the ball at the tip of the support shaft is
A clearance is required between the (53) and the vertical peripheral wall (29) of the upper ring (2), so the runout of the upper ring cannot be eliminated, and rotation stability is a problem for precision work. was there.

Further, in order to prevent the upper ring (2) and the under ring (1) from being separated from each other, the lower edge of the vertical peripheral wall (29) of the upper ring (2) has the support on the under ring (1). It is necessary to install a retaining ring (55) that hangs on the tip of the shaft (51).

As shown in FIG. 6, the retaining ring (55) can be expanded and contracted by cutting it off at one position, and the retaining ring is reduced in diameter and inserted between the bearing (5) and the upper ring (2). Then, the upper ring (2) is hooked on the locking portion (28) to prevent the upper ring (2) from coming off. However, the work of reducing the diameter of the retaining ring and inserting it is troublesome and the assembling efficiency is poor. The present invention is
The purpose of the present invention is to clarify a rotary table having a good rotational stability because the structure and assembly can be further simplified.

[0008]

In order to achieve the above object, the rotary table of the present invention is a rotary table in which a rotating member is interposed between the peripheral walls of the upper ring and the under ring, and the upper ring is rotatably supported by the under ring. In the table, the under ring (1) has a peripheral wall (13) that is inclined in a conical shape or an inverted conical shape and protrudes upward, and the upper ring (2) is a peripheral wall (13) of the under ring (1). Along the slope and the surrounding wall (13)
It has an inclined peripheral wall (23) that fits in from above, and each peripheral wall (13) (23)
Guide grooves (15) and (25) are formed on the opposing surface of the ring around the ring, and a large number of balls (4) are rotatably interposed between the guide grooves (15) and (25), and The lower edge (15b) of the ring guide groove (15) and the upper edge of the guide groove (25) of the upper ring (2)
(25b) extends to the vicinity of a vertical line L ₁ passing through the axis of the ball (4), and the other side edges (15a) and (25a) of the guide grooves of both rings are vertical lines contacting the outermost peripheral surface of the ball. The ball (4) enters the ball side of L ₂ and engages both rings irremovably and rotatably through the ball, and the ball (4) is a retainer (3) made of synthetic resin.
Are retained by the underrings (1) on the upper and lower edges of the retainer.
And a lip portion (33) that is in sliding contact with the peripheral wall of the upper ring (2)
(33) is formed over the entire length of the retainer, projecting to both sides.

[0009]

[Operation and effect] Guide groove (15) (2) of under ring (1)
The balls (4) held by the retainer (3) are lined up in (5) to prevent the balls (4) from sliding down from the guide grooves (15) (25), and the upper ring (2) is placed on the balls (4). ) And press the upper ring (2) in this state. Upper ring
The peripheral walls (13) and (23) of (2) and the under ring (1) are
The upper ring (2) bends so that the space between the peripheral walls opens.
The ball (4) also fits in the guide groove (25) of the.

When the ball (4) fits into both guide grooves (15) and (25), the peripheral walls (13) and (23) return to their original shape, and the rings (13) and (23) are passed through the ball (4). The rings engage with each other and the rings are prevented from being separated from each other via the balls (4).

Lower edge of the guide groove (15) of the under ring (1)
(15b) and the upper edge of the guide groove (25) of the upper ring (2) (25
Since b) covers the vertical line L ₁ passing through the axis of the ball (4), the upper edge of the guide groove (25) of the upper ring (2) (25
The load applied to b) is the lower edge of the under ring (1) located directly below.
Acts on (15b). Therefore, a heavy thrust load can be received.

Further, the upper edge (15b) of the guide groove (15) of the under ring (1) and the lower edge (25a) of the guide groove (25) of the upper ring (2) form the outermost peripheral surface of the ball. It is on the ball side of the passing vertical line L ₂ . Therefore, the contact area between the ball and the guide groove in the radial load direction increases,
Can withstand large radial loads.

Of course, the ball (4) has guide grooves (15) on both rings.
Since the under ring (1) and the upper ring (2) are fitted into (25) and roll, the center of the under ring (1) and the upper ring (2) do not occur, and the rotary table of the present invention can be used as a rotary table for precision work.

Further, a lip portion (3) protruding from the retainer (3)
3) (33) prevents foreign matter from entering between the ball (4) and the guide groove, and can maintain smooth rotation for a long period of time. As described above, the ball (4) is set on the under ring (1), and the upper ring (2) can be assembled simply by pressing and fitting, and the cost can be reduced by simplifying the manufacturing process.

[0015]

[Examples] In the examples, a large-sized turntable for a cargo handling pallet will be described.
Needless to say, it can be applied to a small turntable used for caring for bonsai.

Under ring (1), upper ring (2)
Are both formed by bending a mold material into a ring having a diameter of about 2 m and welding both ends. The under ring (1) is
1) and a peripheral wall (13) that protrudes obliquely upward in a reverse conical shape from the inner peripheral edge of the ring portion. Upper ring (2)
Is composed of a horizontal ring portion (21) and a peripheral wall (23) that protrudes obliquely downward from the inner peripheral edge of the ring portion in a conical shape.

The peripheral wall (13) of the under ring (1) is enlarged on the upper end side, and the peripheral wall (23) of the upper ring (2) is reduced in diameter on the lower end side along the peripheral wall (13) of the under ring (1). The peripheral wall (23) of the ring (2) is replaced by the peripheral wall (1) of the under ring (1).
3) It fits into the room with room. The peripheral walls (13) (23) of both rings are approximately 3 each with respect to the horizontal ring parts (11) (21).
It is tilted by 0 ° and 120 °.

Horizontal ring portions (11) (21) of both rings (1) (2)
A bolt hole (10) for fixing the turntable to the floor and a bolt hole (20) for fixing a worktable such as a pallet on the turntable are provided in the.

At the substantially central portion of the facing surface of each peripheral wall (13) (23),
Guide grooves (15) (25) are formed around the peripheral walls (13) (23) once. The guide grooves (15) and (25) are formed by pressing the peripheral walls (13) and (23) into a groove shape, and then the groove portion is further extended by about 2 mm corresponding to the spherical surface of the ball (4) described later. The depth of the groove bottom is about 1 / the diameter of the ball (4).
Is 3. A grease injection hole (17) is formed in the peripheral wall (13) of the under ring (1), and a grease nipple (not shown) is formed in the hole.
Is attached.

About 30 between the guide grooves (15) and (25) of both rings
A ball (4) having a diameter of 3/4 inch is interposed at a mm pitch.

The balls (4) are held by the retainer (3) made of synthetic resin shown in FIG. 3 so that the distance between the adjacent balls (4) is constant. The retainer (3) has five ball accommodating holes (31) in the strip (30) at equal intervals, and both side edges in the longitudinal direction of the strip (30) are bifurcated lip portions (33) (33). ) Is formed, and the lip portions (33) (33) are formed on the peripheral walls (13) of both rings (1) and (2).
Contact with (23) to prevent dust and foreign matter from entering the ball rolling path.

The required number of retainers (3) are arranged on the guide groove according to the size of the ring.

The lower edge (15) of the guide groove (15) of the under ring
b) and the upper edge (25b) of the guide groove (25) of the upper ring (2)
Is on the vertical line L ₁ passing through the axis of the ball (4), and the other side edges (15a) (25a) of the guide grooves of both rings are closer to the ball than the vertical line L ₂ contacting the outermost peripheral surface of the ball. 1.5 to 2 mm
Intruding, the rings are inseparably and rotatably engaged via the balls.

Next, a procedure for assembling the rotary table will be described.
Retainer (3) with ball (4) fitted under ring (1)
Line up on the guide groove (15) without gaps and support it with an appropriate jig (not shown) so as not to slip off the groove. The ball (4) is covered with the upper ring (2), and the outer edge (25a) of the guide groove (25) is placed on the row of balls (two-dot chain line in FIG. 2).

When the entire length of the upper ring (2) is pressed down evenly, the peripheral walls (13) (23) of both rings are bent in the direction of opening each other, and also in the guide grooves (15) (25) of the upper ring (2). ball
(4) is fitted (solid line in Fig. 2).

When the ball (4) fits into both guide grooves (15) and (25), the peripheral walls (13) and (23) return to their original shape. In this state, the upper edge (15a) of the guide groove (15) of the under ring (1) and the lower edge (25a) of the guide groove (25) of the upper ring (2) are balls.
Since the ball (4) is slightly covered in the retaining direction, the ball (4) has a side edge.
(15a) and (25a) are caught and the separation of both rings is prevented.

Lower edge of the guide groove (15) of the under ring (1)
(15b) and the upper edge of the guide groove (25) of the upper ring (2) (25
Since b) covers the vertical line L ₁ passing through the axis of the ball (4), the upper edge of the guide groove (25) of the upper ring (2) (25
The load applied to b) is the lower edge of the under ring (1) located directly below.
Acts on (15b). Therefore, a heavy thrust load can be received. Also, the upper edge (15b) of the guide groove (15) of the under ring (1) and the guide groove of the upper ring (2)
The lower edge (25a) of (25) is a vertical line L ₂ contacting the outermost peripheral surface of the ball.
It is 1.5 to 2 mm deeper than the ball side, and the contact area between the ball and the guide groove in the radial load direction is large, so a large radial load can be received.

Further, the lip portion (3) protruding from the retainer (3)
3) (33) prevents foreign matter from entering between the ball (4) and the guide groove, and can maintain smooth rotation for a long period of time. The rotary table of the present invention can achieve the same effects as above even if the turntable is turned upside down. Further, when implementing a small rotary table, the under ring and the upper ring can be formed by punching and bending by a press.

[0029]

[Brief description of drawings]

FIG. 1 is a perspective view showing a part of a rotary table in section.

FIG. 2 is a vertical sectional view of a main part of a rotary table.

FIG. 3 is a perspective view of a retainer.

FIG. 4 is a perspective view of a conventional example.

FIG. 5 is a sectional view of a main part of a conventional example.

FIG. 6 is a perspective view of a retaining ring of a conventional example.

[Explanation of symbols]

 (1)… Under ring (2)… Upper ring (15) (25)… Guide groove (3)… Retainer (4)… Ball

Claims (1)

[Claims] 1. In a rotary table in which a rotating member is interposed between the peripheral walls of the upper ring and the under ring, and the upper ring is rotatably supported by the under ring, the under ring (1) has a conical shape or an inverted shape. It has a peripheral wall (13) that is inclined conically and protrudes upward, and the upper ring (2) follows the inclination of the peripheral wall (13) of the under ring (1) and the peripheral wall (1).
3) has an inclined peripheral wall (23) fitted from above, and each peripheral wall (13) (2
Guide grooves (15) and (25) are formed on the opposing surface of 3) around the ring, and a large number of balls (4) are rollably interposed between the guide grooves (15) and (25). , The lower edge (15b) of the guide groove (15) of the under ring and the upper edge (25b) of the guide groove (25) of the upper ring (2) are close to the vertical line L ₁ passing through the axis of the ball (4). The other side edges (15a) (25a) of the guide grooves of both rings extend beyond the vertical line L ₂ contacting the outermost peripheral surface of the ball to the ball side so that both rings cannot be separated and rotate through the ball. Retainer made of synthetic resin and engaged as much as possible, and the ball (4)
At the upper and lower edges of the retainer, lip parts (33) and (33), which are in sliding contact with the peripheral walls of the under ring (1) and the upper ring (2), are extended to both sides and are extended over the entire length of the retainer. Turntable that is formed by.