JPH10169653A - Ball chain - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ball chain wherein it softly follows relating to flexing and twisting, capable of smoothly circulating inside a ball endless track, and even in the case of giving large flexing and twisting, a ball can be surely held, in the ball chain arranging in one line also holding many balls capable of rolling to be used, for instance, assembled in an endless sliding linear guide device and a ball endless track of a ball screw device. SOLUTION: In a ball chain 1 constituted by many balls 3 arranged in one line with a prescribed space apart and a connection unit belt 2 rotatably holding these balls 3 also mutually connecting the balls 3 adjacent to each other, this constitution is formed such that the connection belt unit 2 has four belt members 5 formed into belt shape along an arrangement direction of the ball 3, on the other hand, the belt member 5 is mutually connected to the other belt member 5 between the balls 3 adjacent to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system in which a large number of balls are arranged in a line and are held in a rolling manner. More particularly, the present invention relates to a ball chain that can be used by freely bending or twisting the ball chain.

[0002]

2. Description of the Related Art Conventionally, as a linear guide device for guiding a movable body such as a table along a fixed portion such as a bed, a track rail having a ball rolling groove and a load rolling member opposed to the ball rolling groove are used. A slider having a running groove and having a no-load rolling path for circulating a ball from one end of the load rolling groove to the other end thereof, and a slider moving along the track rail; and a load between the slider and the track rail. And a number of balls circulating in an endless track constituted by a loaded rolling groove of the slider and an unloaded rolling path.

In the conventional linear guide device configured as described above, since the endless track of the slider is filled with the ball, when the slider moves along the track rail,
The balls adjacent to each other circulate in the endless track while colliding or rubbing each other, and there is a problem that the balls are worn early and the life of the device is shortened. When assembling the slider, it is necessary to fill the endless track with a large number of balls. However, since each ball is small and easily rolled, handling the ball is troublesome. The assembly work had to be complicated.

In order to solve these problems, there has been proposed a linear guide device in which a ball chain in which a large number of balls are aligned and held is incorporated in the endless track (Japanese Patent Laid-Open No. 5-52217). As shown in FIGS. 8 and 9, the ball chain 100 has a spacer 102 interposed between balls 101 adjacent to each other and a pair of belt members 103 along the arrangement direction of the balls. The balls 101 are connected in a rosary by connecting with each other, and are manufactured by injection molding of a flexible resin in which the balls 101 are arranged as a core in a mold.

[0005] The conventional ball chain 100 constructed as described above is incorporated in the endless track 105 of the slider 104 and circulates in the endless track. Since the seat 102 is interposed, mutual friction and collision between the balls are prevented, and wear of the ball 101 can be prevented as much as possible. Each ball 101 is a pair of spacers 102, 10
2, the ball is held from both sides and does not fall off from the ball chain 100, so that a large number of balls 101 can be handled as one, and the slider assembling operation can be performed easily by that much. .

[0006]

By the way, when the conventional ball chain 100 constructed as described above is bent, as shown in FIG. It hardly bends at a position adjacent to the seat 102, and largely bends at a position adjacent to the ball 101. Therefore, if it is desired to use the ball chain 100 by bending or twisting more flexibly, the spacer 102 adjacent to each ball 101 is preferably formed as small as possible.

However, as described above, in the conventional ball chain 100, each ball 101 is connected to a pair of spacers 102, 10
The spacer 10 is supported on both sides by two.
2 cannot be formed too small, and if it is formed too small, the ball 101 may fall off when the ball chain 100 is bent or the like. Therefore, the conventional ball chain 100
In this case, the spacer 102 can be formed small, and therefore, the degree of freedom against bending and twisting of the ball chain 100 is low.

[0008] For this reason, depending on the design of the endless track incorporating the ball chain, the ball chain circulating in the endless track may be forcibly bent or twisted, and the smooth circulation of the ball chain is hindered. There was a problem that it would.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object to enable the ball to smoothly follow the bending and torsion and smoothly circulate inside the ball endless track. Another object of the present invention is to provide a ball chain capable of securely holding a ball even when a large bending or twisting is given.

[0010]

That is, the ball chain of the present invention comprises a large number of balls arranged in a line at a predetermined interval, and holds the balls rotatably and mutually adjacent balls. A ball chain composed of connected belts, wherein the connected belt has four belt members formed in a belt shape along the arrangement direction of the balls, and the belt members are adjacent to each other. Between the belt member and the other belt member.

According to the ball chain of the present invention constructed as described above, the connecting member belt has four belt members, and these belt members are connected to each other between adjacent balls. Therefore, the balls arranged in such a connected body belt are in a state of being held by the belt member from all sides, even if the ball chain is twisted or bent,
It does not fall off the connecting body belt.

For this reason, in the ball chain of the present invention, it is not necessary to provide a spacer between the adjacent balls to hold the ball, and the degree of freedom of the ball chain against bending or twisting by the amount of the spacer is omitted. Can be increased.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a ball chain according to the present invention will be described in detail with reference to the accompanying drawings. FIGS. 1 and 2 show an embodiment of a ball chain 1 according to the present invention. The ball chain 1 has a plurality of balls 3 arranged in a row at a predetermined interval on a synthetic resin connecting belt 2.
The ball 3 is freely rotatable while being held by the connecting body belt 2.

The connecting member belt 2 has four belt members 5 formed in a band along the direction in which the balls 3 are arranged.
The belt member 4 is interconnected with another belt member 5 between balls 3 adjacent to each other. A disc-shaped connecting portion 4 is provided between adjacent balls 3.
Are formed, and each belt member 5 is mutually connected to another belt member 5 via the connecting portion 4.

The belt member 5 is disposed on the upper, lower, left and right sides of the ball row so as to divide the spherical surface of the ball 3 into four equal parts, and the ball 3 comes off between a pair of connecting parts 4 adjacent to the ball row. The movement of the ball 3 is constrained from four directions so that there is no movement. The side edges 5a of the belt member 5 are formed in a straight line, and the ball chain 1 is formed to have a uniform width along the direction in which the balls 3 are arranged.

The ball chain 1 is formed by injection molding of a synthetic resin arranged in a mold with the ball 3 as a core, and after the molding is completed, the linked belt 2 is released together with the ball 3 from the mold. Is done. In addition, if the connection belt 2 is simply injection-molded, the connection portion 4 and the belt member 5 of the belt 2 come into close contact with the ball 3 and the ball 3 does not freely rotate with respect to the connection belt 2. In this embodiment, the ball chain 1 after completion of molding is immersed in mineral oil-based lubricating oil, and a gap is formed between the ball 3 and the connecting portion 4 or the belt member 5 after the swelling of the connecting member belt 2 with time. This allows the ball 3 to rotate freely.

According to the ball chain 1 of the present embodiment configured as described above, since the movement of each ball 3 is restricted from four directions by the four belt members 5, the balls 3 adjacent to each other are , 3, there is no need to provide a large spacer that covers the spherical surface of the ball 3 as long as the connecting portion 4 that connects the four belt members 5 to each other is slightly formed. Therefore, in the ball chain of this embodiment, the spacer provided between the balls does not hinder free bending and twisting, and even if a large bending or twisting acts, it can flexibly absorb it. You can do it.

FIG. 3 shows an example of a linear guide device incorporating the ball chain. In the figure, reference numeral 10 denotes a track rail provided for a fixed portion such as a bed of a machine tool, and reference numeral 20 denotes a track endless track in which the ball chain 1 is incorporated and a movable member such as a table is connected to the track rail. A slider that guides along 10,
Reference numeral 3 denotes a ball that rolls while applying a load between the track rail 10 and the slider 20 and that circulates infinitely in the slider 20.

First, the track rail 10 is formed in a substantially rectangular cross section, and a gothic arch-shaped ball rolling groove 11 is provided on both side surfaces along the longitudinal direction (perpendicular to the paper surface of FIG. 2) for a total of two. Articles are formed. The track rail 1 is formed with bolt mounting holes 12 at appropriate intervals in the longitudinal direction, and the track rail 10 is fixed to a fixing portion by a fixing bolt (not shown) inserted into the bolt mounting hole 12. .

The slider 20 has a horizontal portion 20a on which a mounting surface 21 of the movable body is formed and a pair of skirt portions 20b, 20b hanging from the horizontal portion 20a, and is formed in a substantially saddle-shaped cross section. Skirt 20b
On the inner surface side, a gothic arch-shaped load rolling groove 23 facing the ball rolling groove 11 of the track rail 10 is formed. Further, a ball return hole 24 corresponding to each load rolling groove 23 is formed in each skirt portion 20b, and the ball 3 released from the load after rolling through the load rolling groove 23 is completed.
Are rolling in the direction opposite to the rolling direction on the load rolling groove 23.

The slider 20 is manufactured using injection molding of a synthetic resin. That is, the slider 20
Is a metal block body 2 formed by machining
5 is formed by filling the resin portion 22 by injection molding, and the portions requiring mechanical strength, such as the movable body mounting surface 21 and the load rolling surface 23 of the ball 3, are the block body 25. On the other hand, portions where mechanical strength is not important, such as the ball return hole 24, are formed of synthetic resin,
The weight of the slider 20 is reduced as much as possible.

FIG. 4 is a sectional view showing a ball endless track of the slider 20 in which the ball chain 1 is incorporated.
This endless track is completed by fixing the lid 30 made of synthetic resin to both front and rear end surfaces of the slider 20. That is, when the lid 30 is fixed to the slicer 20, the ball guide 26 of the slider 20 is fitted into the U-shaped groove 31 of the lid 30 to complete the U-shaped turning path 32. The turning path 32 connects the load rolling surface 23 of the slider 20 to the ball return hole 24.

FIG. 5 is an enlarged view showing the rolling state of the ball in the endless track. Relief grooves 27, 27 are formed at the deepest portions of the ball rolling groove 11 and the load rolling groove 23 formed in the Gothic arch shape, respectively, and when the ball 3 is rolling in these rolling grooves 23, 11 The belt member 5 of the ball chain 1 is accommodated in the escape groove 27. On the other hand, four guide grooves 28 are formed in the ball return hole 24 of the slider 20 along the longitudinal direction thereof, and the belt member 5 of the ball chain 1 in a no-load state is formed.
Are guided by the guide grooves 28 to prevent the ball chain 1 from meandering inside the ball return hole 24.

According to the linear guide device of the present embodiment configured as described above, the slider 20 is mounted on the track rail 1.
When the ball 3 moves on the slider 20, the ball 3 rolls on the load rolling groove 23 of the slider 20 and the ball rolling groove 11 of the track rail 10, and the ball chain 1 circulates inside the endless track formed on the slider 20. .

At this time, in the linear guide device of this embodiment,
As shown in FIG.
The position of the ball return hole 24 is slightly higher than the position of the ball chain 3, and if the ball chain 1 of the present embodiment described above is to be circulated in the endless track, the ball chain 1 An external force twisting the endless track acts.

At this time, since the ball chain 1 of the present embodiment adopts a structure that can easily absorb bending and twisting flexibly as described above, the load rolling groove 23 and the ball return hole 2 are used.
Even if it has the positional relationship shown in FIG. 5, it can be easily deformed in the endless track, and can smoothly circulate in the endless track.

Next, FIG. 6 shows an example in which the ball chain of this embodiment is incorporated in an endless track of a ball screw device. In the figure, reference numeral 50 denotes a screw shaft on which a spiral ball rolling groove 51 is formed by a predetermined lead, and reference numeral 60 denotes an endless track into which the ball chain 1 is incorporated, and the screw shaft 50 is connected to the screw shaft 50 via the ball 3. It is a screwed nut member.

Here, the nut member 60 is composed of a steel nut main body 62 having a flange 61 for fixing the nut member 60 projecting therefrom, and a composite fixed to both front and rear end surfaces of the nut main body 62. It is composed of a pair of lids 63 made of resin.

The nut body 62 has a helical load rolling groove 64 formed in the inner diameter thereof, which is opposed to the ball rolling groove 51 of the screw shaft 50, and a ball return parallel to the screw shaft 50. A hole 65 is drilled. As shown in FIG. 7, a direction change path 66 is formed in the cover 63 to guide the ball 3 having finished rolling in the load rolling groove 64 of the nut body 62 to the ball return hole 65. By fixing the lid 63 to the nut body 62, the endless track of the ball 3 is completed.

The ball rolling groove 51 of the screw shaft 50
The load rolling groove 64 of the nut main body 62 is formed in a gothic arch shape, and a relief groove for accommodating the belt member 5 of the ball chain 1 is formed at the deepest portion of each groove similarly to the above-described linear guide device. ing.

Further, similarly to the above-described linear guide device, the belt member 5 of the ball chain 1 is provided in the direction changing path 66 of the lid 63 and the ball return hole 65 of the nut body 62.
Are formed along the longitudinal direction, and the ball chain 1 wound around the outer circumference of the screw shaft 50 is accommodated in the direction change path 66 of the lid 63 in a predetermined posture. It has become.

According to the ball screw device of the present embodiment configured as described above, when the screw shaft and the nut member rotate relatively, the ball 3 incorporated in the ball chain 1 loads the nut member 60 with the load. Rolling groove 64 and screw shaft 50
The ball chain 1 circulates in the endless track formed in the nut member 60.

At this time, in the ball screw device of the present embodiment, since the ball chain 1 is spirally wound around the outer periphery of the screw shaft 50, the ball chain 1 is twisted in the endless track. Is circulating. Particularly, when the ball chain 1 enters the direction change path 66 of the lid 63 from the outer periphery of the screw shaft 50, as shown in FIG. It is necessary to make the approach, and the bending and twisting motion of the ball chain in the endless track must be more intense than the circulation in the linear guide device described above.

However, since the ball chain 1 of the present embodiment employs a structure that can easily absorb bending and torsion as described above, the ball chain 1 can easily circulate through the endless orbit of the nut member. This enables smooth circulation of the ball chain in the endless track.

Further, even if the ball chain is frequently bent or twisted, the ball is completely enclosed by the connecting member belt in the ball chain of the present embodiment, so that the ball can be removed from the ball chain. An accident such as a ball falling off from the endless track without falling off can be prevented.

[0036]

As described above, according to the ball chain of the present invention, since the connecting member belt wraps the ball from all sides by the four belt members, the ball chain is located between adjacent balls. Even without providing a spacer for enclosing the spherical surface of the ball, such a ball can be reliably prevented from falling off the connecting body belt, so that even if a large bending or torsion acts on the endless track. This can be flexibly absorbed, and the circulation in such an endless track can be facilitated.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a ball chain of the present invention.

FIG. 2 shows the ball chain II-II shown in FIG.
It is a line sectional view.

FIG. 3 is a sectional view showing an example of a linear guide device into which the ball chain of the present invention is incorporated.

FIG. 4 is a sectional view showing a ball endless track of the linear guide device shown in FIG. 3;

FIG. 5 is a cross-sectional view showing a rolling state of the ball in the ball track shown in FIG. 4;

FIG. 6 is a sectional view showing an example of a ball screw device into which the ball chain of the present invention is incorporated.

FIG. 7 is an enlarged view of a main part of the ball screw device shown in FIG. 6;

FIG. 8 is a plan view showing a conventional ball chain.

FIG. 9 is a side view showing a conventional ball chain.

FIG. 10 is a side view showing a bent state of a conventional ball chain.

[Explanation of symbols]

1 ... ball chain, 2 ... connecting body belt, 3 ... ball,
4 ... Connecting part, 5 ... Belt member

Claims (3)

[Claims] 1. A ball chain comprising a number of balls arranged in a line at a predetermined interval, and a connecting belt which holds the balls rotatably and connects adjacent balls to each other. The linked body belt has four belt members formed in a belt shape along the ball arranging direction, and the belt members are mutually connected to other belt members between adjacent balls. A ball chain characterized by being. 2. The ball chain according to claim 1, wherein the belt member is arranged so that the connecting member belt divides a spherical surface of each ball into four equal parts. 3. The ball chain according to claim 1, wherein a side edge portion of each belt member is formed in a straight line, and the connecting member belt has a uniform width along a ball arranging direction. A ball chain, characterized by being.