JP2020112196A - Linear rail capable of detecting abnormal situation of circumfluence - Google Patents

Abstract

To provide a linear rail.SOLUTION: A linear rail comprises a rail and a slide section. The slide section is attached to the rail so as to form a loading path between the rail and the slide section. The slide section has: two non-loading paths penetrating both edge faces of the slide section opposite to each other; a plurality of force sensors arranged at both edges of the two non-loading paths; and two side caps arranged on both edge faces opposite to each other. Each side cap has two circumfluence grooves. Each circumfluence groove is connected to one edge of the loading paths and one edge of the non-loading path so as to form a circulation path among the same. Balls roll along the circulation path. With aforementioned structural characteristics, the linear rail can detect loading force at both edges of the non-loading paths when being subject to impacts of the balls through the force sensors and determine whether or not balls are abnormally stacked up in the circulation path and collide each other.SELECTED DRAWING: Figure 2

Description

The present invention relates to a linear rail, and particularly to a linear rail that can detect an abnormal circulation situation.

A conventional linear rail includes a rail, a sliding part, two side caps and a circulation path. The slide portion is arranged on the rail. The two side caps are arranged at both front and rear ends of the slide part. The circulation path is composed of a rail, a slide part and two side caps. The plurality of balls operate along a circulation path.

In order to ensure the smooth operation of the ball, the prior art discloses a method of detecting whether or not the circulation is abnormal by various types of sensors.
Patent Document 1 discloses disposing a sensor in a load path in order to detect a moving distance of a slide portion or a nut.
Patent Document 2 discloses disposing a sensor for detecting prestress at an arm portion of a load path.
However, since the problem that the ball is caught in the load path in the presence of the prestress between the slide portion and the rail is unlikely to occur, even if the sensor is arranged in the load path as in Patent Document 1 and Patent Document 2, the flow is circulated. It is difficult to detect the abnormal situation of the robot immediately.

German Patent DE19713688B4 German Patent DE102016205575A1

The main object of the present invention is to provide a linear rail that can immediately detect an abnormal situation of circulation.

A linear rail for solving the above-mentioned problem includes a rail, a slide portion, two side caps, a plurality of balls, and a plurality of force sensors. The rail has two opposite outer rolling grooves on the outer peripheral surface. The slide portion has a slide groove. The slide part is arranged on the rail so that the slide part can slide. The slide groove has two opposing inner rolling grooves on the wall surface. The inner rolling groove of the slide portion and the outer rolling groove of the rail correspond to each other and a load path is formed between them. The slide portion also has two opposite unloaded paths. Each unloaded path extends through two opposite end faces of the slide. The two side caps are disposed at two opposite ends of the slide portion, each having a swirl groove. The circulation grooves of the two side caps each have one end connected to one end of the load path and another end connected to one end of the non-load path. The two circulation grooves, the load path and the non-load path are combined to form a circulation path that operates a plurality of balls. The plurality of force sensors are arranged in pairs at both ends of the two non-loaded paths in order to detect the load forces of the two non-loaded paths that are impacted by the plurality of balls.

In the situation where the ball is easily caught at the bend of the circulation path, the linear rail according to the present invention uses at least one force sensor separately arranged at both ends of the non-load path to detect the load force signal at each end of the non-load path. It is possible to effectively determine immediately whether or not the circulation is abnormal by detecting

The arrangement positions of the plurality of force sensors are not limited to the above, and may be changed according to the actual situation. That is, a force sensor is arranged on the outer peripheral surface of the circulation pipe, the circulation pipe is inserted into the non-load path to connect one end of the circulation pipe to the circulation groove of the side cap, and the force sensor is embedded in the fitting groove. The fitting groove can be located on the inner wall surface of each non-load path.

Detailed structure, characteristics, assembling or use method of the linear rail according to the present invention will be clarified through the following detailed description of the embodiments.
It should be noted that the following detailed description and the embodiment presented by the present invention are merely examples for explaining the present invention, and that the scope of the present invention cannot be limited by a person who has common knowledge in the area related to the present invention. Then you should understand.

1 is a perspective view showing a linear rail according to a first exemplary embodiment of the present invention. FIG. 3 is an exploded perspective view showing a state in which a part of rails in the linear rail according to the first embodiment of the present invention is omitted. 1 is a sectional view showing a linear rail according to a first exemplary embodiment of the present invention. FIG. 4 is an enlarged view of a part of FIG. 3. FIG. 8 is an exploded perspective view showing a part of a linear rail according to a second exemplary embodiment of the present invention. FIG. 8 is a sectional view showing a part of a linear rail according to a second embodiment of the present invention.

Hereinafter, a linear rail according to the present invention will be described with reference to the drawings. In the specification, the same reference numerals in the drawings indicate structural features of the same parts or similar parts.

(First embodiment)
As shown in FIGS. 1 and 2, the linear rail 10 according to the first exemplary embodiment of the present invention includes a rail 20, a slide unit 30, two side caps 40, and a plurality of force sensors 60.

The rail 20 has two outer rolling grooves 22 separately below and on both side surfaces.

The slide portion 30 has a slide groove 31. The slide portion 31 slides along the rail 22 by fitting the slide groove 31 to the rail 20. The slide groove 31 has two inner rolling grooves 32 separately above and below the wall surface.
As shown in FIG. 3, the inner rolling groove 32 of the slide portion 30 and the outer rolling groove 20 of the rail 20 correspond to each other one by one to form a load path 52 between them. The slide part 30 further has two unloaded paths 33 above and below the two opposite outer sides of the slide groove 31, respectively. All the non-load paths 33 penetrate two front and rear end surfaces of the slide portion 30.

The two side caps 40 are arranged on the two front and rear end surfaces of the slide portion 30. Since the two side caps 40 have the same structure, one of the side caps 40 will be described.
As shown in FIG. 2, the side cap 40 has a lid main body 41, a circulation member 42, and a plate portion 44. The lid body 41 is arranged so as to abut the end surface of the slide portion 30. The circulation member 42 is fitted in the lid body 41 and has two circulation grooves 43 separately above and below both sides of the inner end surface.
As shown in FIG. 3, one end of each circulation groove 43 is connected to the load path 52, and another end is connected to the non-load path 33. The front and rear two opposing circulation grooves 43, one load path 52 and one non-load path 33 are combined to form a circulation path 54 that operates a plurality of balls 50. The plate portion 44 is arranged on the outer end surface of the lid main body 41, and is attached to the slide portion 30 integrally with the lid main body 41 by a fastening member (not shown in the figure) such as a screw to shield the diversion member 42.

The plurality of force sensors 60 are arranged in pairs. In this embodiment, the number of force sensors 60 is 16.
As shown in FIGS. 2 to 4, all the unloaded paths 33 have a circulation pipe 34 inside. Both ends of all the circulation pipes 34 are separately connected to one end of the circulation groove 43. Since the pair of force sensors 60 are arranged one by one on the outer peripheral surface of the one end of the circulation pipe 34, it is possible to immediately detect the load forces of all the non-load paths 33 that are impacted by the plurality of balls 50.

The ball is often caught at a curved portion of the circulation path 54, that is, at both ends of the unloaded path 33. By disposing the force sensors 60 at the curved portion of the circulation path 54, that is, at both ends of the non-load path 33, it is possible to easily detect an abnormally increased load force signal.
When the load force signal increases abnormally, that is, when the ball 50 comes into contact with the inner wall surface and becomes clogged, the force sensor 60 transmits the detected load force signal to one control module 62 in the lid body 41 to proceed with the analysis. By doing so, it is determined in advance whether or not the circulation is abnormal. In a relatively preferred case, all force sensors 60 are located no more than twice the size of the ball diameter from the opening at one end of the unloaded path 33. In other words, the distance between the position of all force sensors 60 and the opening at one end of the unloaded path 33 is less than twice the diameter of the ball 50. Due to the above-mentioned structural characteristics, the force sensor 60 can effectively detect the load force signal that is abnormally increased due to the ball 50 contacting both ends of the non-load passage 33 and being clogged.

(Second embodiment)
In contrast to the first embodiment in which the force sensor 60 is indirectly arranged at one end of the unloaded path 33 by the circulation pipe 34, the force sensor 60 is directly arranged at one end of the load path 33 in the second embodiment. More specifically, as shown in FIGS. 5 and 6, all the unloaded paths 33 have two opposing fitting grooves 35 on the inner wall surfaces at both ends.
If one force sensor 60 is embedded in all the fitting grooves 35, the force sensor 60 can accurately detect the impact force generated by the plurality of balls 50 colliding with the non-load path 33. In a relatively preferred case, all force sensors 60 are located no more than twice the size of the ball diameter from the opening at one end of the unloaded path 33.

In summary, the linear rail 10 according to the present invention detects whether or not the balls 50 are abnormally jammed and hit each other by the force sensors 60 directly or indirectly arranged at both ends of the unloaded path 33. It is possible to detect the circulatory condition more accurately and achieve the effect of the pre-diagnosis as compared with.

10 linear rail 20 rail 22 outer rolling groove 30 slide portion 31 slide groove 32 inner rolling groove 33 non-load path 34 swirl pipe 35 fitting groove 40 side cap 41 lid body 42 swirl member 43 swirl groove 44 plate portion 50 ball 52 Load path 54 Circulation path 60 Force sensor 62 Control module

Claims (4)

With rails, slides, two side caps, multiple balls and multiple force sensors,
The rail has two opposing outer rolling grooves on the outer peripheral surface,
The slide part has a slide groove and two opposite non-loaded paths, the slide groove has two opposite inner rolling grooves on a wall surface, and each of the non-loaded paths has two of the two non-loaded paths of the slide part. Penetrating opposite end faces,
The slide portion is arranged on the rail so as to be slidable by the slide groove, and the inner rolling groove of the slide portion and the outer rolling groove of the rail correspond to each other to form a load path therebetween. ,
The two side caps are disposed at two opposite ends of the slide portion and each have a swirl groove. One end of each swirl groove of each of the side caps is connected to the load path, and one end of the swirl groove is connected to the load path. Since it is connected to the non-load path, the two circulation grooves, the load path and the non-load path are combined to form a circulation path,
A plurality of the balls are arranged in the two circulation paths,
A plurality of the force sensors are arranged at both ends of each of the non-load paths,
Linear rail. The linear rail according to claim 1, wherein each of the non-load paths has a fitting groove on the inner wall surface of the both ends, and each of the fitting grooves has the force sensor therein. Each of the non-load paths has a circulation pipe inside, each of the circulation pipes has both ends separately connected to the circulation groove of the side cap, and has the force sensor on the outer peripheral surface of the both ends. The linear rail according to claim 1. The linear rail according to claim 1, wherein each of the force sensors is arranged at a position not more than twice the diameter of the ball from the opening at one end of the non-load path.

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