JPH1089356A - High load capacity direct acting guide bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high load capacity direct acting guide bearing which has the high loading capacity against great load such as impact load, however can set up the loading capacity that is appropriate but no more than overloading, at the time of normal loading in the range of light and intermediate loading. SOLUTION: A load receiving groove 13B running in parallel with a ball rolling grooves 13A and 13C is provided for both the side surfaces of a guide rail 11, concurrently a load receiving groove 15B faced to the load receiving groove 13B is also provided for the inner side surfaces at both the wing parts of a slider 12, and a load receiving member 21 which is brought into contact with the groove surfaces of the load receiving grooves 13B and 15B when the load pivotally supported by a ball 20 exceeds the over static rated load, is fitted out in the space of a load receiving groove 16B made out of both the load receiving grooves 13B and 15B faced 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 linear guide bearing having a high load capacity, and more particularly, to a load bearing through a number of balls circulating while rolling between a guide rail and a slider freely traveling on the guide rail. This is an improvement in the load capacity and rigidity of the linear motion guide bearing.

[0002]

2. Description of the Related Art Conventional linear motion guide bearings of this type include:
For example, there is one disclosed in Japanese Utility Model Publication No. 6-646.
(First conventional example). This should be small on both sides of the guide rail.
At least three rows of ball rolling grooves are formed.
On the sleeves of the slider movably mounted on the
Ball rolling groove facing the ball rolling groove and parallel to the ball rolling groove
A ball circulation path is provided, and a slider is
With many balls circulating while rolling with the movement of
I have. Then, as shown in FIGS.
These balls B are ball rolling grooves 3A on the guide rail 1 side,
3B, 3C and the ball rolling on the slider 2 side opposed thereto.
Two points (T) between the groove surfaces with the moving grooves 5A, 5B, 5C ₁, T_Two)
In contact.

A similar type of linear guide bearing is disclosed, for example, in Japanese Utility Model Laid-Open Publication No. 64-53622 (second conventional example). This is a three-row ball rolling groove structure similar to the above, as shown in FIG. 16, but the upper row of the opposing ball rolling grooves 3A, 5A and the lower row of the opposing ball rolling grooves 3C. , 5C, the ball B is brought into contact with the groove surface at two points T ₁ , T ₂ , and in the ball rolling grooves 3B, 5B of the intermediate stage, the ball B is contacted with the groove surface at four points T ₁ , T 2. _The contact is made at ₂ , T ₃ and T ₄ .

Further, Japanese Unexamined Utility Model Publication No. Hei 3-59519 (third conventional example) has a three-row ball rolling groove structure as shown in FIG. Opposing ball rolling grooves 3A-5A, 3B-5 in each step
B, contact points T ₁ and T ₂ between the groove surface of 3C-5C and ball B
The extended lines of the straight lines connecting the two meet each other at an angle of 60 degrees.

[0005]

However, in each of the above-mentioned first to third conventional examples, a large number of balls roll in the grooves in each of the upper, middle, and lower steps which are basically long in the axial direction. It is a structure to do. In this case, the portion where the ball contacts the groove surface is elastically deformed when a load is applied to the slider 2 and becomes an elliptical contact surface (contact ellipse). Due to such a structure that receives a load with a small area of contact ellipse, for example, when an impact load is applied to the slider 2, a large force is locally applied to the guide rail in contact with the ball or the groove surface of the ball rolling groove of the slider. However, there is a problem that a smooth impression is hindered.

Accordingly, the present invention has been made in view of such a conventional problem. In a linear motion guide bearing device having a plurality of ball rolling grooves, the present invention is applied to a large load such as an impact load. With high load capacity,
It is an object of the present invention to provide a high load capacity linear motion guide bearing capable of setting an appropriate load capacity that does not cause an excessive load capacity in a state without an impact load or the like.

[0007]

In order to achieve the above-mentioned object, a linear guide bearing device according to the present invention is provided in which a slider is straddled on a guide rail having ball rolling grooves formed on both side surfaces, and the slider is provided. A ball circulation path comprising a ball rolling groove opposed to the ball rolling groove, a ball return path parallel to the ball rolling groove, and curved paths disposed at both ends of the ball rolling groove is provided on both sleeves of the sleeve. And a load receiving groove parallel to the ball rolling groove is provided on both side surfaces of the guide rail, and a load receiving surface opposed to the load receiving groove is formed on both inner side surfaces of the slider. A groove is provided, and a load receiving member that is in contact with the groove surfaces of the load receiving grooves at a load equal to or more than the static rated load supported by the ball is loaded in the space between the opposing load receiving grooves.

According to the present invention, when a normal load (light load or moderate load) is applied to the slider, the load is applied via the balls in the ball rolling grooves. At this time, the load receiving member mounted in the load receiving groove on the slider side is not in contact with the groove surface of the load receiving groove on the opposite guide rail side. Therefore, the guide rail and the slider can move lightly and smoothly by the rolling contact of the ball.

However, when a large load such as an impact load (a load not less than a preset static rated load) is applied to the slider, the load receiving member also comes into contact with the groove surface of the load receiving groove on the guide rail side. I do.

[0010] Therefore, since most of the load is borne by the load receiving member, only a load equal to or less than the static rated load is applied to the upper and lower grooves, resulting in a high load capacity.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 to 4 show an embodiment of the present invention. FIG. 1 is a front view showing a right half of an end cap with the right half thereof removed. FIG. 2 is a sectional view taken along line II-II of FIG.
FIG. 4 is an enlarged view of the ball groove. In the drawings, members having the same functions are denoted by the same symbols. First, the configuration will be described. A slider 12 having a substantially U-shaped cross section is laid on a guide rail 11 so as to be relatively movable.
On both sides of the guide rail 11, three rows of ball rolling grooves 13A, 13B, and 13C are formed in the axial direction in upper, middle, and lower stages, and the cross section of each of the grooves has two identical curvatures having different centers. Are formed in a substantially V-shape with the circular arc surface of, and are so-called Gothic arch grooves.

On the other hand, a ball rolling groove 15A facing the upper ball rolling groove 13A of the guide rail and a middle ball rolling groove 13B are formed on the inner surface of both sleeves 14 of the main body 12A of the slider 12. A ball rolling groove 15B opposed to
Ball rolling groove 1 opposed to lower ball rolling groove 13C
5C are formed, and the ball rolling paths 16A, 16B, and 16C are formed by the three opposing grooves in the upper, middle, and lower rows. Further, a ball return path 17A having a circular cross section parallel to the ball rolling path 16A, a ball return path 17B parallel to the ball rolling path 16B, and a ball A ball return path 17C parallel to the moving path 16C is formed so as to penetrate in the axial direction.

On the other hand, the end caps 18, which are respectively joined to the front and rear ends of the slider body 12A, have semi-donut-shaped curved paths 19A, 19B, 19C formed in three stages of upper, middle and lower. The upper curved path 19A connects the ball rolling path 16A and the ball return path 17A, the middle curved path 19B connects the ball rolling path 16B and the ball return path 17B, and the lower curved path 19C The ball rolling path 16C communicates with the ball return path 17C.

Here, ball rolling paths 16A, 16B, 16C formed between the guide rail 11 and the slider 12 are provided.
Will be described in detail with reference to FIG. In the case of this embodiment,
In the upper ball rolling path 16A, the ball rolling groove 15A on the slider side is slightly offset (δ) from the ball rolling groove 13A on the guide rail side to the center of the groove. In the ball rolling path 16B in the middle stage, the ball rolling groove 15B on the slider side does not offset the groove center with respect to the ball rolling groove 13B on the guide rail side.
On the other hand, in the lower ball rolling path 16C, the ball rolling groove 15C on the slider side is slightly offset (δ) below the groove center with respect to the ball rolling groove 13C on the guide rail side. And, the upper ball rolling path 16
A, a plurality of balls 20 are respectively circulated in a ball circulation path formed by A, a curved path 19A, a ball return path 17A, and a lower ball rolling path 16C, a curved path 19C, and a ball return path 17C. . Thus, the ball 20 in the upper ball rolling path 16A comes into contact with the groove surface of the ball rolling groove 15A on the slider 12 at the point T1, and the ball surface of the ball rolling groove 13A on the guide rail 11 side Contact at point T2. On the other hand, the ball 20 in the lower ball rolling path 16C is provided with the ball rolling groove 15C on the slider 12 side.
Contact with the groove surface of the ball rolling groove 13C on the guide rail 11 side at a point T2. Therefore, the straight lines L1 and L2 connecting the contact points T1-T2 of the balls in the ball rolling paths 16A and 16C are of a high rigidity type in which the inclination is opposite and the intersection Q is located outside the guide rail 11. .

On the other hand, the middle ball rolling path 16B
Is not loaded with the ball 20. This ball rolling path 16B
Is a load receiving groove, and the load receiving member 2
1 is attached. As shown in FIG. 4, the load receiving member 21 has a cylindrical shape that is somewhat longer than the axial length of the slider body 12A and has a diameter somewhat smaller than that of the ball 20, and protrudes from both ends of the slider body 12A. The end is hooked to the back surface of the end cap 18 and attached. The material of the load receiving member 21 is, for example, S45.
Steel materials such as C are preferable. The method of attaching the load receiving member 21 is not limited to the above. For example, as shown in FIG. 5, both ends of a round bar are curved in a U-shape, and the curved ends 21 are formed.
a into the curved path 19B on the back surface of the end cap 18 or as shown in FIG. May be inserted into the hole of.

The load receiving member 21 fixed at both ends in this way and attached to the ball rolling path 16B which is a load receiving groove.
In the state of a normal load load, as shown in FIG. 3, two points are held in contact with the groove surface of the ball rolling groove 15B which is the load receiving groove on the slider 12 side, and the load receiving groove on the guide rail 11 side is held. Is not in contact with the groove surface of the ball rolling groove 13B.

Next, the operation will be described. When the slider 12 on the guide rail 11 is moved in the axial direction, the ball 20 inserted into the ball rolling path 16A (and 16C) is slower than the moving speed of the slider 12 while rolling along with the movement of the slider 12. Move in the same direction at speed. Then, at the end of the slider 12 in the moving direction, the direction is changed by being guided to the ball scooping portion S provided on the end cap 18,
Make a U-turn along the curved path 19A (19C). Subsequently, the curved path 19A (1) of the end cap 18 on the opposite side passes through the ball return path 17A (17C) of the slider body 12A.
9C) again makes a U-turn and the ball rolling path 16A
Returning to (16C), the circulation that moves while continuing the rolling is repeated.

The relationship between the load direction and the rigidity is as follows. When a normal load such as a light load or a medium load (that is, a load equal to or less than the static rated load of the linear motion guide bearing calculated without the load receiving member 21) is acting on the slider 12, the load is The ball 20 in the upper ball rolling path 16A or the lower ball rolling path 16C according to the direction
The load is supported through one of the balls 20 in the inside.
At this time, the load receiving member 21 is not in contact with the groove surface on the guide rail side, and does not bear the load. Therefore, a smooth operation is performed as the rolling and linear motion guide bearing.

However, when a large load such as a heavy load exceeding the static rated load or an impact load is applied to the slider 12, the slider 12 behaves differently from the above. That is, FIG.
As shown in (a), if an impact load F in the compression direction acts on the upper surface of the slider 12, the sleeve 1 of the slider 12
4 is compressed downward, resulting in the upper ball rolling path 16A.
Ball 20 also changes the point of contact with the groove surface to share the applied load P _F located within. At the same time, the load receiving member 21 attached to the ball rolling path 16B, which is the middle load receiving groove, is not only capable of receiving the load on the guide rail 11 but also on the groove surface of the ball rolling groove 15B, which is the load receiving groove on the slider 12. both groove surfaces of the ball rolling groove 13B is receiving groove to share the applied load P _F becomes to two points contact the contact.

Thus, in the linear guide bearing of the present embodiment, not only the balls 20 in the ball rolling grooves of the upper and lower ball rolling paths 16A and 16C, but also in the middle load receiving grooves. The impact load F is received via the load receiving member 21. As shown in FIG. 7B, when an impact load F in the pulling direction acts on the upper surface of the slider 12, the impact load F is shared by both the ball 20 and the load receiving member 21 according to the same principle. To receive.

FIG. 8 shows a contact state between each ball 20 and the load receiving member 21 and the groove surface when sharing such an impact load F. The ball 20 and the groove surface have a small contact ellipse 22. On the other hand, the cylindrical load receiving member 21 and the groove surface form a rectangular contact surface 23 that is long in the axial direction.

Thus, according to the first embodiment, the load receiving member 21 having a large contact area can share more impact load F than the ball 20 having a small contact area, and the load acting on the ball 20 is small. Thus, it is possible to prevent an indentation at a portion where the ball 20 contacts the groove surface of the guide rail 11 or the slider 12.

Since the cylindrical load receiving member 21 having a large contact area bears a large load such as an impact load, it has the highest static load rating as a linear motion guide bearing using balls as rolling elements. There is an effect that things can be provided.

[0024] Thus, even in a large machine tool or a heavy object conveying machine in which an impact load is naturally applied, a book using a ball instead of the conventional one in which the load-loading ability is increased by using rollers as rolling elements. It becomes possible to incorporate the linear guide bearing of the invention.

The load receiving member 21 also has a fail-safe function for preventing the slider 12 from falling off from the guide rail 11, and therefore, in a use mode in which the linear guide bearing is mounted on the ceiling in an upside-down manner, the load receiving member 21 may be subjected to a collision or the like. Even if the ball 20 falls out of the groove due to the accident described above, the slider does not fall off the guide rail and falls, and safety is guaranteed.

FIGS. 9 and 10 show a second embodiment of the present invention. This embodiment differs from the first embodiment in that a dedicated load receiving groove is formed without using the existing ball rolling path 16B. As the load receiving member 21, a cylindrical member having a considerably smaller diameter than the ball 20 is used. A load receiving groove 25 for mounting the small-diameter load receiving member 21.
Is also small. The load receiving groove 25 is provided in the upper ball rolling path 16.
A, a gothic arch-shaped load receiving groove 26 formed on the side surface of the guide rail 11 and a Gothic formed on the inner surface of the slider 12 opposed thereto. The small-diameter load receiving member 21 is held in contact with the groove surface of the load receiving groove 27 on the slider side.

In the range of light load or medium load, the load receiving member 2
1 is not in contact with the groove surface of the load receiving groove 26 on the guide rail side. However, when a large load F such as an impact load is applied, the load receiving member 21 contacts the groove surface of the load receiving groove 26 on the guide rail side as shown in FIG.

Therefore, even if the load receiving member 21 is smaller in diameter than the ball 20, the same operation and effect as in the first embodiment can be obtained. The load receiving groove 25 in this case is
Since the ball rolling path 16B is not diverted as in the first embodiment, the ball return path 17B is unnecessary.

FIGS. 11 and 12 show a third embodiment of the present invention. As described above, the load receiving member 21, the gothic arch-shaped load receiving groove 26 formed on the side surface of the guide rail 11 to which the load receiving member 21 is mounted, and the gothic arch-shaped load receiving groove 26 formed on the inner surface of the slider 12 opposed thereto. And the load receiving groove 25, which is constituted by the load receiving groove 27, and the ball rolling paths 16A, 16B.
The same operation and effect can be obtained even if provided at a position not in the middle of the above.

FIGS. 13 and 14 show a fourth embodiment of the present invention. In this embodiment, the load receiving member 2 is used instead of the ball 20 by using the ball rolling path 16B in the middle stage as a load receiving groove.
1 is the same as the first embodiment. However, the contact point T1 at which the ball 20 in the upper ball rolling path 16A contacts the groove surface of the ball rolling groove 15A on the slider 12 and the contact point at which the ball 20 contacts the groove surface of the ball rolling groove 13A on the guide rail 11 side. The straight line L1 connecting the point T2, the contact point T1 where the ball 20 in the lower ball rolling path 16C contacts the groove surface of the ball rolling groove 15C on the slider 12, and the ball rolling groove 13C on the guide rail 11 side. The straight line L2 connecting the contact points T2 contacting the groove surface is an example of a case where the present invention is applied to a self-aligning type in which the inclination is opposite and the intersection Q is located inside the guide rail 11. In this case, the ball rolling groove 13 on the guide rail 11 side in the upper ball rolling path 16A.
In A, the upper half is missing, and the lower ball rolling path 1
In the ball rolling groove 13C on the guide rail 11 side in 6C, the lower half groove surface is flat and the clearance is large.

In the case of this type, the slider 12
When an impact load acts in the compression direction from above to below (FIG. 14 (a)), the balls that share the load are not all of the balls 20 in the ball rolling paths 16A and 16C, but the upper ball. Only the ball 20 in the rolling path 16A is provided. However, in this embodiment, the cylindrical load receiving member 21 mounted in advance receives most of the load on the rectangular contact surface having a large contact area.
No indentation is caused by the contact of.

When an upward impact load is applied to the slider 12 in the pulling direction (FIG. 14B), the only ball that bears the load is the ball 20 in the lower ball rolling path 16C. However, also in this case, since the cylindrical load receiving member 21 receives most of the applied load, no indentation occurs due to the contact of the ball 20.

In each of the first to third embodiments,
Although all the ball rolling paths on which the balls roll are formed as Gothic arch grooves, the ball rolling paths need not necessarily be Gothic arch grooves.

Further, the ball rolling grooves are not necessarily limited to upper and lower two steps or upper, middle and lower three steps.

[0035]

As described above, according to the high load capacity linear motion guide bearing of the present invention, the load receiving grooves parallel to the ball rolling grooves are formed on both side surfaces of the guide rail and on both inner surfaces of the sleeves of the slider. In the space between the opposed load receiving grooves, a cylindrical load receiving member that is in contact with the groove surfaces of the load receiving grooves at a load equal to or greater than the static rated load supported by the ball is used. Most of the load exceeding the normal static rated load, such as an applied impact load, is received by the load receiving member, so that the load sharing by the ball can be greatly reduced, and the generation of indentation can be prevented. It has the effect of being able to provide a high load capacity linear motion guide bearing that has a high load capacity with respect to the load and sets an appropriate load capacity that does not become an excessive load capacity under a normal load state to ensure smooth operation.

Further, the load receiving member also has a fail-safe function for preventing the slider from falling off the guide rail, so that the safety is guaranteed even in a use mode in which the linear motion guide bearing is mounted upside down on the ceiling. It works.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view of a first embodiment of a linear motion guide bearing according to the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a partially enlarged view of a main part of FIG. 1;

FIG. 4 is a perspective view illustrating one mounting mode of the load receiving member of the present invention.

FIG. 5 is a perspective view illustrating another mounting mode of the load receiving member of the present invention.

FIG. 6 is a perspective view illustrating still another attachment mode of the load receiving member of the present invention.

FIGS. 7A and 7B are diagrams showing the distribution of the load on the slider according to the first embodiment of the present invention, wherein FIG. 7A shows the case of a compressive load and FIG.

FIG. 8 is a diagram illustrating a state of contact between a ball and a load receiving member on a groove surface according to the first embodiment of the present invention.

FIG. 9 is a partially enlarged view of a main part in the second embodiment.

FIGS. 10A and 10B are diagrams showing the distribution of load on a slider according to the second embodiment, wherein FIG. 10A shows a case of a compressive load and FIG. 10B shows a case of a tensile load.

FIG. 11 is a partially enlarged view of a main part in a third embodiment.

FIGS. 12A and 12B are diagrams showing the distribution of the load on the slider according to the third embodiment, in which FIG. 12A shows the case of a compressive load, and FIG.

FIG. 13 is a partially enlarged view of a main part in a fourth embodiment.

FIGS. 14A and 14B are diagrams showing the distribution of the load on the slider according to the fourth embodiment, in which FIG. 14A shows a case of a compressive load, and FIG.

FIG. 15 shows an example of a load distribution diagram on a slider in a conventional linear guide bearing device, where (a) shows a compressive load,
(B) is for a tensile load.

FIG. 16 is another example of a sharing diagram of the load on the slider in the conventional linear guide bearing device.

FIG. 17 is a diagram showing a load state on a slider in a conventional linear guide bearing device.

[Explanation of symbols]

 11 Guide rail 12 Slider 13A Ball rolling groove (of guide rail) 13B Ball rolling groove (of guide rail) 13C Ball rolling groove (of guide rail) 14 Sleeve 15A Ball rolling groove (of slider) 15B Ball rolling Moving groove (of slider) 15C Ball rolling groove (of slider) 16B Load receiving member 17A Ball return path 17B Ball return path 17C Ball return path 19A Curved path 19B Curved path 19C Curved path 20 Ball 21 Load receiving member 25 Load receiving groove 26 Load receiving groove (on the guide rail side) 27 Load receiving groove (on the slider side)

Claims (1)

[Claims] A slider is straddled on a guide rail having ball rolling grooves formed on both side surfaces, and a ball rolling groove opposed to the ball rolling groove and a ball return parallel to the ball rolling groove are provided on both sleeves of the slider. A linear motion guide bearing having a ball circulation path composed of a path and curved paths disposed at both ends thereof, and the ball circulation path being loaded with a large number of balls, wherein the ball rolling grooves are formed on both side surfaces of the guide rail; A parallel load receiving groove is provided, and a load receiving groove opposed to the load receiving groove is provided on the inner side surface of each of the sleeves of the slider. In a space between the opposed load receiving grooves, a static load equal to or more than the static rated load supported by the ball is provided. A high load capacity linear motion guide bearing, wherein a load receiving member that contacts the groove surfaces of both load receiving grooves under load is loaded.